US20200340186A1

US20200340186A1 - Railway switch mechanism and method for operating a railway switch mechanism

Info

Publication number: US20200340186A1
Application number: US15/931,627
Authority: US
Inventors: Bo Johansson
Original assignee: Vertex Sweden AB; Ve'rtex Sweden AB
Current assignee: Vertex Sweden AB; Ve'rtex Sweden AB
Priority date: 2017-11-14
Filing date: 2020-05-14
Publication date: 2020-10-29
Also published as: EP3710636A4; EP3710636A1; SE1751407A1; SE542061C2; WO2019098925A1

Abstract

The disclosure relates to railway switch mechanism comprising a first switch blade and/or first switch frog rail segment that is vertically displaceable by means of a first displacement mechanism in order to establish a vertical switch movement of the first switch blade and/or first switch frog rail segment between an upper and lower switch state; and a second switch blade and/or second switch frog rail segment that is vertically displaceable by means of a second displacement mechanism in order to establish a vertical switch movement of the second switch blade and/or second switch frog rail segment between an upper and lower switch state. The disclosure also relates to a corresponding method for operating such a railway switch mechanism.

Description

TECHNICAL FIELD

This disclosure relates to a railway switch mechanism comprising a first and a second switch blade and/or a first and a second switch frog rail segment that is vertically displaceable by means of a first or second displacement mechanism in order to establish a vertical switch movement between an upper and lower switch state. The disclosure also relates to a corresponding method. The railway switch mechanism may typically be used for enabling switching from following a main railway route to or from a railway diverging route or opposite.

BACKGROUND

It is commonly known that railway switches have problems with reliability when operating in winter conditions due to snow and ice preventing correct switching of the switch blades. Snow and ice may block proper switching motion of the switch blades, such that railway service personnel may have to be requested for servicing. One known attempt for reducing the problems of blocking due to snow and ice is electrical heating of the railway switch. Electrical heating is however costly due to the significant amount of electrical energy required for heating. Consequently, there is a demand for further improved railway switch with respect to operating reliability and cost.

SUMMARY

An object of the present disclosure is to provide a railway switch mechanism where the previously mentioned problem is at least partly avoided. This object is achieved by the features of the independent claims.
According to a first aspect of the invention, the object of the present disclosure is at least partly achieved by a railway switch mechanism comprising a first switch blade or first switch frog rail segment that is vertically displaceable by means of a first displacement mechanism in order to establish a vertical switch movement of the first switch blade or first switch frog rail segment between an upper and lower switch state; and a second switch blade or second switch frog rail segment that is vertically displaceable by means of a second displacement mechanism in order to establish a vertical switch movement of the second switch blade or second switch frog rail segment between an upper and lower switch state.
According to a second aspect of the invention, the object of the present disclosure is also at least partly achieved by a method for operating a railway switch mechanism, the method comprising establishing a vertical switch movement of a first and second switch blade or first and second switch frog rail segment between an upper and lower switch state, the first switch blade or first switch frog rail segment is vertically displaceable by means of a first displacement mechanism in order to establish a vertical switch movement of the first switch blade or first switch frog rail segment between an upper and lower switch state, and a second switch blade or second switch frog rail segment that is vertically displaceable by means of a second displacement mechanism in order to establish a vertical switch movement of the second switch blade or second switch frog rail segment between an upper and lower switch state.
The problem of unreliable switching during winter condition is primarily caused by the fact that snow and ice easily get clamped between stock rails and switch blades upon horizontal motion of the switch blades. There is simply no effective means available for avoiding the clamping of the snow and ice during horizontal switching motion. Similar problems may occur due when debris, stones or other particles are getting clamped by the horizontally moving switch blades. The solution provided by the invention is based on using vertical switching motion of the switch blades instead.
By adopting a vertical switching motion the risk for clamping snow and ice between the switch blades and another component of the switch mechanism is significantly reduced. The space between the switch blade and stock rails in a direction transverse to the longitudinal direction of the rails is substantially identical in both switching positions of the switch blades, such that substantially no snow and ice can enter this space at any time. Furthermore, even if any snow or ice would become located in the region of the switch blades, the likelihood that said snow and ice will cause any substantial harm is low because there is plenty of opportunity for any snow or ice to be pushed away during switching motion without becoming clamped between two parts such as to negatively influence the reliability or functionality of the switch.
A switch frog as such improves the safety, functionality and passenger comfort by means of eliminating or at least reducing the gap that exists in fixed stationary frogs. The gap is necessary for enabling the flange of each wheel to pass the frog in each travelling direction of the frog. A wheel passing a stationary frog thus generally temporarily lack proper lateral support, and the wheel will typically descend a certain distance into the gap before hitting the continuing rail path on the other side of the gap, such to induce a shock and generate noise. A switch frog, i.e. a frog than can selectively fill the gaps between a frog point and associated closure tracks by means of switching at least one switching element, reduces or substantially eliminates those problems. Known solutions for switch frogs rely on switching a rail segment moving in the horizontal direction, such as for example a swingnose crossing. However, this type of switch frogs experience the same problems as discussed above in relation to switch blades, namely blocking of proper switching motion of the switching rail segments by snow and ice. The solution defined by the independent claims, namely to use vertically moving switching rail segments in the switch frog, provide essentially the same advantages for the switch frog as described in relation to the switch blades.
Blocking of a vertical switching motion by snow and ice is much more difficult than blocking of a horizontal switching motion due to the lack of opposing surfaces that approaches each other during switching motion. In horizontal switching motion a side surface of the switch blade is located opposite and facing a side surface of the stock rail, and said side surfaces are approaching or retreating from each other during switching motion. In vertical raising switching motion however, no surface is available vertically above the switch blade or switch frog rail segment, such that essentially no blocking can occur. Moreover, in vertical lowering switching motion of the switch blades or switch frog rail segments, it is a theoretical possibility that snow and ice may get trapped at an underside of the switch blade or rail switch frog segment, but this may be avoided by providing sufficient vertical space underneath the switch blades and switch frog rail segments. The space underneath a vertically moveable switch blade or switch frog rail segment may also be better protected and sealed from entering snow and ice compared with a conventional railroad switch mechanism having horizontal switching motion.
According to one example embodiment of the disclosure, each of the first and second displacement mechanisms may comprise a motion control arrangement configured for providing vertical displacement of an associated switch blade or switch frog rail segment in response to horizontal displacement of at least one lower motion control member, and at least one pair of cooperating upper and lower load-carrying members that are configured to be in contact with each other and transmit load from the associated switch blade or switch frog rail segment to the lower load-carrying member via the upper load-carrying member when the associated switch blade or switch frog rail segment is in the upper switch state. An advantage of splitting motion control and load-carrying of the switch blades and/or switch frog rail segments into two separate functional arrangements, i.e. the motion control arrangement and the pair of cooperating upper and lower load-carrying members, is that each functional arrangement may be better adapted to its unique requirement while using a more cost-efficient design.
According to one example embodiment of the disclosure, the at least one pair of cooperating upper and lower load-carrying members are configured to be not in contact with each other at least partly along a displacement path of the upper and lower load-carrying members from the upper switch state to the lower switch state. Thereby, the motion control functionality and load-carrying functionality can be separated from each other to a greater extent, thereby enabling a larger freedom of design of each functional arrangement.
According to one example embodiment of the disclosure, the at least one pair of cooperating upper and lower load-carrying members are configured to be not in contact with each other at a lower switch state of an associated switch blade or switch frog rail segment. Thereby, the motion control functionality and load-carrying functionality can be separated from each other to a greater extent, thereby enabling a larger freedom of design of each functional arrangement.
According to one example embodiment of the disclosure, the at least one pair of cooperating upper and lower load-carrying members are configured to be in contact with each other only in a region of an upper switch state when moving along a displacement path of the upper and lower load-carrying members from the upper switch state to the lower switch state. Thereby, the motion control functionality and load-carrying functionality can be separated from each other to a greater extent, thereby enabling a larger freedom of design of each functional arrangement.
According to one example embodiment of the disclosure, each of the first and second switch blades or each of the first and second switch frog rail segments, for enabling the vertical switch movement of the first and second switch blades or the first and second switch frog rail segments, may be: elastically bendable in the vertical direction; or pivotally connected to the railway switch mechanism by hinged joints located at or near ends of first and second closure rails of the railway switch mechanism; or translatory moveable between the upper and lower switch state.
By having the switch blades or switch frog rail segments elastically bendable in the vertical direction for enabling the desired vertical displacement thereof any discrete hinged connection point to the closure rail is eliminated, such that a more continuous rail is provided. Each discontinuation, each gap, in the rail implies more noise, more vibrations, less robustness and reliability. A continuous rail is thus generally advantageous. The switch blade/switch frog rail segment and associated closure rail are thus essentially the same element, since no specific location can be determined separating the switch blade/switch frog rail segment from the closure rail. Moreover, by using the natural vertical elasticity of the switch blades or switch frog rail segments more conventional railway track components may be used in the switch mechanism, thereby reducing cost of the switch mechanism.
Alternatively, when the vertical switch movement is enabled by pivotal connection of the first and second switch blades or the first and second switch frog rail segments to the railway switch mechanism by hinged joints located at or near ends of first and second closure rails of the railway switch mechanism, less force is typically required for providing the switching movement, because no elastic deformation of the rail is required. Still more alternatively, when each of the first and second switch blades or each of the first and second switch frog rail segments is translatory moveable between the upper and lower switch state, a more compact design is possible with respect to the length of the first and second switch blades or first and second switch frog rail segments, since an effective length of the first and second switch blades or first and second switch frog rail segments with respect to sufficiently lowered vertical position is increased. In fact, using translatory moveable switch blades or switch frog rail segments means that the entire length of the switch blades or switch frog rail segments is an effective length with respect to sufficiently lowered vertical position. Moreover, the force needed to perform the switch motion is much lower compared with the force needed to bend the switch blades or switch frog rail segment elastically in the vertical direction.
According to one example embodiment of the disclosure, the motion control arrangement, for enabling a vertical switch movement of the first or second switch blade or first or second switch frog rail segment from the lower switch state to the upper switch state, may be configured for providing upward vertical displacement of an associated switch blade or switch frog rail segment beyond the upper switch state, such that a downward-facing load-carrying surface of an upper load-carrying member is located vertically offset from a upward-facing load-carrying surface of a lower load-carrying member, and subsequently providing downward vertical displacement of the associated switch blade or switch frog rail segment to the upper switch state, in which the downward-facing load-carrying surface of the upper load-carrying member contacts and enables load transmission from the associated switch blade or switch frog rail segment to the upward-facing load-carrying surface of the at the lower load-carrying member.
According to one example embodiment of the disclosure, the railway switch mechanism may further comprise a support frame in which each of the first and second displacement mechanisms are located, wherein the support frame has a bottom and at least two substantially longitudinal side walls carrying first and second outer rails and enclosing the first and second displacement mechanisms, and wherein each of the first and second displacement mechanisms is fastened to the support frame. A support frame enables high control and accuracy of the relative position of the elements of the switch mechanism, as well as heating of the switch mechanism. The bottom of the support frame may have a rectangular shape and a side wall on each side thereof, i.e. four side walls surrounding a hollow inside of the support frame. The support frame also enables quick and efficient installation of a railway switch because the railway switch may largely be pre-manufactured and subsequently merely transported to the building site and lifted of. Moreover, an insulating cover may be provided on the exterior side of the support frame for providing an improved heat transfer barrier.
According to one example embodiment of the disclosure, each of the first and second displacement mechanisms may be located in at least one individual casing having an exterior protrusion, wherein each substantially longitudinal side wall of the support frame comprises at least one corresponding recess, and wherein each individual casing is secured to the support frame by means of the exterior protrusion being positioned in a corresponding recess in a substantially longitudinal side wall of the support frame. This design enables a quick, reliable and cost-efficient installation of the individual casings in the support frame.
According to one example embodiment of the disclosure, each of the first and second displacement mechanisms may be located in at least two individual casings that are arranged substantially aligned in a substantially longitudinal direction and interconnected by a moveable driving member. Thereby repair and service of a displacement mechanism is simplified and made more cost-efficient because only a part of the displacement mechanism can be replaced, instead of replacing the entire displacement mechanism.
According to one example embodiment of the disclosure, each individual casing may comprise first and second longitudinal side walls, wherein the exterior protrusion of each individual casing is located in the first longitudinal side wall of the casing, and wherein the exterior protrusion of each individual casing is prevented from escaping from a corresponding recess in a substantially longitudinal side wall of the support frame by means of at least one threaded member located near the second longitudinal side of each individual casing and arranged to clamp the casing to the bottom of the support frame. This design enables a quick, reliable and cost-efficient installation of the individual casings in the support frame.
According to one example embodiment of the disclosure, the railway switch mechanism may further comprise a first stationary outer rail located on one of the two longitudinal side walls of the support frame, a second stationary outer rail located on the other of the two longitudinal side walls of the support frame, a first stationary lateral support structure attached to the support frame and located between the first stationary outer rail and the first displacement mechanism and configured for providing lateral support to the first stationary outer rail, and a second stationary lateral support structure attached to the support frame and located between the second stationary outer rail and the second displacement mechanism and configured for providing lateral support to the second stationary outer rail. High lateral stability of the first and second stationary outer rails is important for enabling a safe, robust and reliable switch mechanism.
According to one example embodiment of the disclosure, each of the first and second stationary lateral support structures may be attached to an interior side of a longitudinal side wall of the support frame. This design enables a very strong and reliable attachment of the first and second stationary lateral support structures.
According to one example embodiment of the disclosure, the support frame may be made of concrete material, wherein each of the first and second stationary lateral support structures comprises anchor elements being cast-in with the material of the support frame. This design enables a very strong and reliable attachment of the first and second stationary lateral support structures.
According to one example embodiment of the disclosure, each of the first and second stationary lateral support structures may be fastened to the first and second outer rail, respectively. This enables improved lateral stability of the first and second stationary outer rails.
According to one example embodiment of the disclosure, each of the first and second stationary lateral support structures may be fastened to the first or second outer rail while allowing a certain degree of relative motion in the vertical direction. A small degree of relative motion in the vertical direction of the first and second outer rail enables use of rail pad or similar device located below first and second outer rail for reducing vibration and noise, while allowing the stationary lateral support structures to be rigidly attached to the support frame.
According to one example embodiment of the disclosure, each of the first and second stationary lateral support structures may be fastened to the first or second outer rail by means of a threaded member that is threadingly engaged in a threaded hole of a lateral support structure, wherein threaded member extends through a hole that has an inner diameter that is larger than the outer diameter of the shank of the threaded member, and wherein difference in size between an inner diameter of the threaded hole and the outer diameter of the shank of the threaded member provides said certain degree of relative motion.
According to one example embodiment of the disclosure, the support frame may be provided with an electrical heating mechanism located near each of the first and second stationary lateral support structures. Support frame heating may be an advantageous additional feature for further enhancing the winter functionality of the switch mechanism.
According to one example embodiment of the disclosure, the railway switch mechanism may further comprise a rail pad of elastic material located between each of the first and second outer rails and the longitudinal side wall of the support frame, as seen in the vertical direction. A rail pad enables a small degree of motion in the vertical direction of the first and second stationary outer rails for reducing vibration and noise.
According to one example embodiment of the disclosure, the railway switch mechanism may further comprise elastic fill material located, at least intermittently in a substantially longitudinal direction, between each of the first and second outer rails or first and second closure rails and an elevated portion of the longitudinal side wall of the support frame, as seen in the transverse direction, for providing improved lateral support to each of the first and second outer rails or first and second closure rails.
According to one example embodiment of the disclosure, the support frame may further comprise a water draining channel located between each of the first and second displacement mechanisms and the associated longitudinal side wall of the support frame for enabling draining of water from the interior of the support frame. Water that may freeze to ice that interfere with the switch motion of the switch blades or switch frog rail segments is undesirable within the support frame.
According to one example embodiment of the disclosure, the support frame may be made of two, three or more individual support frame sections. By having the support frame composed of a plurality of individual sections that are placed and possible interconnected when properly installed, simplified installation and transportation of the switch mechanism is provided, because the individual sections are smaller and lighter than a complete and fully assembled switch mechanism. Moreover, in case of damage of an individual support frame section only part of the switch mechanism can be replaced instead of the complete switch mechanism, such that repair and service of the switch mechanism is made more cost-efficient.
According to one example embodiment of the disclosure, the first and second displacement mechanisms may be driven by first and second driving members, respectively, wherein the railway switch mechanism further may comprise a single power source that simultaneously drives both the first and second driving members. This enables a more cost-efficient design because a single power source is needed instead of one power source for each switch blade/rail segment.
According to one example embodiment of the disclosure, the at least one pair of cooperating upper and lower load-carrying members comprises a locking arrangement for mutually interlocking the upper and lower load-carrying members in the upper switch state for preventing relative vertical motion, preferably relative vertical and transverse motion, between the upper and lower load-carrying in the upper switch state. This enables a more safe, reliable and robust design.
According to one example embodiment of the disclosure, the motion control arrangement may further comprise at least one upper motion control member, wherein the at least one lower motion control member and the at least one upper motion control member are configured to interact for translating a substantially horizontal displacement of the at least one lower motion control member to a substantially vertical displacement of the at least one upper motion control member, and wherein the at least one upper motion control member is directly or indirectly fastened to the first or second switch blade or first or second switch frog rail segment, such that the first and second switch blades or first or second switch frog rail segment can be selectively positioned in an upper and lower switch state by substantially horizontal displacement of the at least one lower motion control member.
According to one example embodiment of the disclosure, the at least one lower motion control member may be configured to be displaced a direction substantially parallel to a longitudinal direction of the first or second switch blade or first or second switch frog rail segment. Thereby, vertical displacement of a relatively long switch blade or rail segment may be controlled by means of a single actuator in a compact packing. For example, a single actuator may be connected directly and/or indirectly to multiple interconnected lower motion control members arranged in series.
According to one example embodiment of the disclosure, the lower motion control member may be configured to interact with the upper motion control member via at least one inclined sliding surface or via at least one pivoting joint.
According to one example embodiment of the disclosure, horizontal displacement of the at least one lower motion control member is configured to cause relative horizontal displacement between the load-carrying surfaces of the at least one lower load-carrying member and the at least one upper load-carrying member, thereby enabling lowering of the associated switch blade or associated switch frog rail segment from the upper switch state to the lower switch state.
According to one example embodiment of the disclosure, the at least one lower load-carrying member may be rigidly connected directly or indirectly to the at least one lower motion control member, such that they move uniformly.
According to one example embodiment of the disclosure, each of the first and second displacement mechanisms comprises at least one pair of cooperating upper and lower wedge-shaped load-carrying members that are configured to transmit load from the associated switch blade or switch frog rail segment to the lower load-carrying member via the upper load-carrying member when the associated switch blade or switch frog rail segment is in the upper switch state, and configured for providing vertical displacement of an associated switch blade or switch frog rail segment in response to horizontal displacement of the lower wedge-shaped load-carrying member.
According to one example embodiment of the disclosure, one of the at least one lower motion control member and at least one upper motion control member may comprise a track with an inclined path, and the other of the at least one lower motion control member and at least one upper motion control member may comprise a guide member arranged to be guided by the track.
According to one example embodiment of the disclosure, the switch mechanism may be suitable for switching railway wheels of a railway car traveling on a railway diverging in to a first and a second route, and the switch mechanism may comprise a first pair of running rails diverging into a second and third pair of running rails, wherein the first pair of running rails may comprise a first and a second outer rail and the switch frog may diverge into a first and a second inner rail, the second pair of running rails may comprise the first outer rail and the first inner rail, the third pair of running rails may comprise the second outer rail and the second inner rail, the first switch blade may extend at least partly between the first outer rail and the switch frog, and the second switch blade may extend at least partly between the second outer rail and the switch frog.
According to a further example embodiment of the disclosure, each of the first and second vertical displacement mechanisms is provided with a first and second intermediate support member, respectively, and configured for controlling the vertical displacement of said first and second intermediate support member, respectively, between the upper and lower switch state, and each of the first and second switch blade or first and second switch frog rail segment is non-movably attached relative to an upper surface of the first and second intermediate support member, respectively, over a longitudinal length that corresponds to 25%-80%, specifically 40%-75%, of a total length of the first and second vertical displacement mechanisms mechanism, and each of the first and second switch blade or first and second switch frog rail segment is vertically movably attached or unattached relative to an upper surface of the first and second intermediate support member, respectively, over a longitudinal length that corresponds to 20%-75%, specifically 25%-60%, of a total length of the first and second vertical displacement mechanisms mechanism.
By having the first and second switch blade or first and second switch frog rail segment is vertically movably attached, or even unattached, relative to an upper surface of the first and second intermediate support member, respectively, over a longitudinal length that corresponds to 20%-75%, specifically 25%-60%, of a total length of the first and second vertical displacement mechanisms mechanism, a free floating region of the first and second switch blade or first and second switch frog rail segment is provided, which allows a vertical gap to be formed between the first and second switch blade or first and second switch frog rail segment and an underlying support structure in an area close the heel. Thereby, relatively cost-efficient and standardised casing design with translatory movements of the upper support surface may be used.
The term “vertically movably attached” referred herein means an attachment that is configured for allowing a vertical displacement of at least 1 centimetre, specifically at least 2 centimetres, of the first and second switch blade or first and second switch frog rail segment relative to an upper surface of the first and second intermediate support member. According to a further example embodiment of the disclosure, each of the first and second vertical displacement mechanisms is provided with a first and second intermediate support member, respectively, and configured for controlling a vertical displacement of said first and second intermediate support member, respectively, between the upper and lower switch state, and each of the first and second switch blade or first and second switch frog rail segment is attached to an upper surface of the first and second intermediate support member, respectively, and each of the first and second switch blades or first and second switch frog rail segments, for enabling the vertical switch movement, are elastically bendable in the vertical direction, or pivotally connected to the railway switch mechanism by a hinged joint, and each of the first and second intermediate support members is translatory moveable between the upper and lower switch state. Thereby, relatively cost-efficient and standardised casing design with translatory movements of the upper support surface may be used, and the elastically or pivotally vertically displaced switch blade provides high operating security, reliability and driving comfort because at least one end of the switch blade is always with certainty located at a correct location in the upper switching state.
According to a further example embodiment of the disclosure, the first and second closure rails of the railway switch mechanism may be vertically movably attached or unattached relative to an upper surface of a support structure over a longitudinal length in the range of 1-5 metres starting from the heel of the first and second switch blade or first and second switch frog rail segment. Thereby, a certain level of lifting of the first and second closure rails are possible, thereby reducing the overall stress level in the material of the switch blades.
According to a further example embodiment of the disclosure, the railway switch mechanism may further comprise a slab track section installed side by side with the support frame for providing support to first and second closure rails, and the first and second closure rails of the railway switch mechanism may be vertically movably attached or unattached relative to an upper surface of the slab track section. The slab track section provides improved stability and robustness for compensating the reduced stability caused by having the first and second closure rails vertically movably attached or unattached.
Further areas of applicability will become apparent from the description provided herein.

BRIEF DESCRIPTION OF DRAWINGS

In the detailed description below reference is made to the following figure, in which:

FIG. 1 shows a schematic top view of an example embodiment of the switch mechanism.

FIG. 2 shows an enlarged schematic top view of an example embodiment of the switch mechanism of a first and second switch blade,

FIG. 3a shows schematically an example cross-section of the switch mechanism along line A-A in FIG. 1 with the switch mechanism in a first switch state,

FIG. 3b shows schematically an example cross-section of the switch mechanism along line A-A in FIG. 1 with the switch mechanism in a second switch state,

FIG. 4 shows schematically an example attachment of an outer rail to an associated stationary lateral support structure,

FIG. 5a shows a schematic cross-section of a first example embodiment of a railway switch mechanism having a switch blade in an upper switch state,

FIG. 5b shows a schematic cross-section of the first example embodiment of a railway switch mechanism having a switch blade in a lower switch state,

FIG. 6a shows a schematic cross-section of a second example embodiment of a railway switch mechanism having a switch blade in an upper switch state,

FIG. 6b shows a schematic cross-section of the second example embodiment of a railway switch mechanism having a switch blade in a lower switch state.

FIG. 6c shows a schematic cross-section of an example embodiment of a railway switch mechanism having a pivotally connected switch blade in a lower switch state,

FIG. 7a shows a schematic cross-section of a third example embodiment of a railway switch mechanism having a switch blade in an upper switch state,

FIG. 7b shows a schematic cross-section of the third example embodiment of a railway switch mechanism having a switch blade in a lower switch state,

FIG. 8 shows schematically an example embodiment of a pair of cooperating upper and lower load-carrying members in a load transmitting state,

FIG. 9 shows schematically a further example embodiment of a pair of cooperating upper and lower load-carrying members in a load transmitting state,

FIG. 10a shows schematically a 3-D view of an example embodiment of a pair of cooperating upper and lower load-carrying members,

FIG. 10b shows schematically a cross-section of the pair of cooperating upper and lower load-carrying members of FIG. 10 a,

FIGS. IIa-IIb shows schematically two alternative example embodiments of a lower motion control member,

FIG. 12a-12d shows schematically a displacement path of a pair of cooperating upper and lower load-carrying members and a motion control arrangement from a lower switch state to an upper switch state,

FIG. 13a-13b shows a schematic cross-section of a fourth example embodiment of a displacement mechanism including a pair of cooperating upper and lower load-carrying members and a motion control arrangement in an upper and lower switch state,

FIG. 14a-14b shows a schematic cross-section of a fifth example embodiment of a displacement mechanism including a pair of cooperating upper and lower load-carrying members and a motion control arrangement in an upper and lower switch state,

FIG. 15a-15b shows a schematic cross-section of a sixth example embodiment of a displacement mechanism including a pair of cooperating upper and lower load-carrying members and a motion control arrangement in an upper and lower switch state.

FIG. 16a-16b shows a schematic cross-section of a seventh example embodiment of a displacement mechanism in an upper and lower switch state,

FIG. 17a-17b shows a schematic cross-section of a eight example embodiment of a displacement mechanism in an upper and lower switch state,

FIG. 18 shows schematically a cross-section of an example embodiment of a locking device,

FIG. 19 shows schematically an example embodiment of a common power casing comprising a power source and first and second driving members,

FIG. 20a-20b shows schematically a cross-section of a further example embodiment of a displacement mechanism,

FIG. 21 shows schematically an exaggerated deflection view of the second switch blade of FIG. 20 b,

FIG. 22 shows a schematic top view of an example embodiment of the switch mechanism of the first and second switch blade,

FIG. 23a-23b shows schematically an example cross-section of the switch mechanism according to FIG. 22 in two different switching states,

FIG. 24 shows schematically an example embodiment of a slab track section, and

FIG. 25-26 shows cross-sections of the slab track section in various switching states.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Various aspects of the disclosure will hereinafter be described in conjunction with the appended drawings to illustrate and not to limit the disclosure, wherein like designations denote like elements, and variations of the described aspects are not restricted to the specifically shown embodiments, but are applicable on other variations of the disclosure.
FIG. 1 of the drawings schematically illustrates a right-hand railway switch mechanism 100 suitable for switching railway wheels of a railway car traveling on a railway diverging in to a first and a second route A, B. The switch mechanism 100 comprises a first pair of running rails 110 diverging into a second and third pair of running rails 120; 130 respectively. The first pair of running rails 110 comprises a first and a second outer rail 111; 112, also sometimes referred to as stockrails. The switch mechanism 100 further comprises a switch frog 150 that is connected to a first and a second diverging inner rails 121; 132. The second pair of running rails 120 comprises the first outer rail 111 and the first inner rail 121, wherein the first outer rail 111 sometimes is referred to as outer straight lead rail. The third pair of running rails 130 comprises the second outer rail 112 and the second inner rail 132, wherein the second outer rail 112 sometimes is referred to as inner curve lead rail.
A first switch blade 141 extend at least partly between the first outer rail 111 and the switch frog 150, and a second switch blade 142 extend at least partly between the second outer rail 112 and the switch frog 150. A switch point 145 a; 146 a of each of the first and the second switch blades 141; 142 is vertically displaceable in order to establish a vertical switch movement in the respective switch point 145 a; 146 a.
In the embodiment of FIG. 1, the first and second switch blades 141, 142 have no distinct and exact length because both the first and second switch blades are vertically displaceable by means of elastic bending of the switch blades 141, 142 within an elastic deformation zone of the material. There is thus a gradual transformation of the switch blades 141, 142 into fixed rail segments upon approaching the switch frog, which fixed rail segments located between the switch frog and switch blades 141, 142 are referred to as first and second closure rails 170, 171.
Each railway switch blade 141, 142 is provided with a respective displacement mechanism 200 a, 201 a by means of which at least a portion of the first and second switch blade 141, 142 can be displaced in a vertical direction to at least an upper and a lower switch state. Each of the first and second switch blades 141, 142 is fastened on a top side of an individual displacement mechanism 200 a, 201 a for enabling the desired vertical displacement of the switch blades 141, 142.
The switch mechanism 100 additionally comprises a switch frog 150. The switch frog may also be referred to as switchable crossing. The switch frog 150 comprises a frog tip 151 and first and second vertically displaceable rail segments 144, 143 in order to establish a vertical switch movement at the switch frog 150. The switch movement at the switch frog is arranged to selectively establish a continuous rail path between the first and second closure rails 170, 171 and the frog tip 151 respectively.
Conventional stationary and non-controlled frogs comprise a gap in each rail at the frog tip 151 for enabling the flange of the railway wheels to pass the frog. Without such a gap a railway wheel could never escape out from the boundaries of the right and left rail tracks due the wheel flange that extends downwards below the upper rolling surface of the rails. The gap at the crossing however enables this escape, such that a railway vehicle can switch from one track to another track. However, it is sometimes desirable to close the gap at the frog for improving comfort, handling and safety of the frog. Conventional switch frogs use horizontal motion of the frog tip for enabling switching of the switch frog. The switch frog rail segments 144, 143 according to the invention are instead configured to be vertically displaceable between upper and lower switch states by means of elastic bending of the switch frog rail segments 144, 143 within an elastic deformation zone of the material.
In the example embodiment of FIG. 1, each switch frog rail segment 144, 143 is provided with an individual vertical displacement mechanism 200 b, 201 b by means of which at least a portion of the first and second switch frog rail segments 144, 143 can be displaced in a vertical direction to at least an upper and a lower position. Each of the first and second switch frog rail segments 143, 144 is fastened on a top side of an individual displacement mechanism 200 b, 201 b for enabling the desired vertical displacement of the switch frog rail segments 143, 144. As discussed in relation to the switch blades 141, 142, a vertical displacement results in significantly improved winter reliability and robustness compared with a horizontally displaced frog tip at the switch frog 150.
In the example embodiment of FIG. 1, the switch mechanism 100 is arranged on a first support frame 160 a associated with the first and second switch blades 141, 142 and a second support frame 160 b associated with the first and second switch frog rail segments 143, 144.
The first and second support frames 160 a, 160 b are provided partly for providing strong structural support to the switch mechanism 100, for ensuring that the vertical displacement mechanisms 200 a, 201 a remain in correct relative location to the switch blades 141, 142 and outer rails 111, 112, and for enabling cost-efficient manufacturing and installation of the switch mechanism by enabling prefabrication of the switch mechanism including rail segments, switch blades, closure rails, switch frog, frame, etc. The first and second support frames 160 a, 160 b may for example be made of concrete material.
A longitudinal direction L herein denotes a direction parallel to the first pair of running rails 110 directly before the switch mechanism 100, and the transverse direction T is extending perpendicular to longitudinal direction L, i.e. laterally to the longitudinal direction L. A vertical direction V is perpendicular to both the longitudinal and transverse direction L, T.
A longitudinal length D1 of the displacement mechanism 200 a, 201 a of the switch blades 141, 142 may typically be in the range of 10-70% of the longitudinal distance D2 between a gap of the switch frog 150 to a distal end of the displacement mechanism 200 a, 201 a, specifically in the range of 10-50%, more specifically in the range of 20-40%. The longitudinal length D1 of the displacement mechanism 200 a, 201 a is preferably short for enabling use of a compact and cost- effective displacement mechanism 200 a, 201 a, but the rigidity of the switch blades 141, 142 may require a relatively long longitudinal length D1 for enabling a sufficient gradual elastic deformation of the switch blades 141, 142 for allowing a wheel flange of a railway wheel to pass the vertically downward-displaced switch blade 141, 142 without contact therebetween and an additional safety margin for allowing for variations over time. The longitudinal length D1 of the displacement mechanism 200 a, 201 a, 200 b, 201 b may typically be in the range of 3-20 meters, specifically 3-12 meters, and more specifically in the range of 4-8 meters, for example depending on the radius of curvature of the diverging railway track.
In the example embodiment of FIG. 1, the first and second outer rails 111, 112 are arranged at least partly on two longitudinal side walls 162 a of the first support frame 160 a. The overall shape of the first support frame 160 a may be adapted to the location and extension of the first and second outer rails 111, 112 while striving towards surrounding substantially the entire first and second displacement mechanisms 200 a, 201 a. As a result, the first support frame 160 a may depending on the layout of the total railway switch have a non-symmetrical shape, as seen from above.
Both the first and second outer rails 111, 112 may be arranged on a longitudinal side wall 162 a along substantially the entire longitudinal length LI of the first support frame 160 a. In the example shown in FIG. 1, the first support frame 160 a has a rectangular shape, as seen from above. However, the longitudinal side wall 162 a of the first support frame 160 a located towards the side of the diverging track may alternatively be shaped to gradually diverge outwards towards the diverging track for enabling the second outer rail 112 to be mounted on top of, and follow the extension of the side wall 162 a along substantially the entire longitudinal length of the first support frame 160 a.
Furthermore, the first and second outer rails 111, 112 are also arranged at least partly on two longitudinal side walls 162 b of the second support frame 160 b. The overall shape of the second support frame 160 b may be adapted to the location and extension of the first and second outer rails 111, 112 while striving towards surrounding substantially the entire first and second displacement mechanisms 200 a, 201 a. As a result, the second support frame 160 b may depending on the layout of the total railway switch have a non-symmetrical shape, as seen from above.
Each of the first and second support frame 160 a, 160 b may additionally comprise two transverse side walls 164 a, 164 b that cooperates with the longitudinal side walls 162 a, 162 b for forming a continuous side wall that surrounds an internal space 163 a, 163 b of each support frame 160 a, 160 b.
In the example shown in FIG. 1, longitudinal side wall 162 b of the second support frame 160 b located towards the side of the diverging track is shaped to gradually diverge outwards towards the diverging track for enabling the second outer rail 112 to be mounted on top of, and follow the extension of the side wall 162 b along substantially the entire longitudinal length of the second support frame 160 b. However, the side walls 162 b of the second support frame 160 a may alternatively define a rectangular shape, as seen from above.
Each vertical displacement mechanism 200 a, 201 a, 200 b, 201 b of the switch blades 141, 142 and switch frog rail segments 144, 143 has generally an elongated shape oriented substantially in the longitudinal direction L. The reason behind this shape is partly for enabling the vertical displacement of the switch blades 141, 142 and rail segments 144, 143 to occur solely based on elastic bending of the switch blades 141, 142, rail segments 144, 143 and any closure rails 170, 171, and partly for providing the necessary vertical support to the switch blades 141, 142 and rail segments 144, 143 for carrying the load of a railway car without unacceptable level of deflection.
The switch blades 141, 142 and rail segments 144, 143 are similar to a cantilever beam in that they are permanently and non-movably anchored at one end only, i.e. a heel end. The switch blades 141, 142 and rail segments 144, 143 are typically made of steel and must therefore have a significant length for enabling the desired vertical displacement at the switch points 145 a, 146 a, 145 b, 146 b of the switch blades 141, 142 and rail segments 144, 143 without exceeding the limit for permanent deformation of the switch blades 141, 142 and rail segments 144, 143.
Unless the displacement mechanisms 200 a, 201 a, 200 b, 201 b provide a distributed underlying support to the switch blades 141, 142 and rail segments 144, 143 they may locally deflect downwards when carrying the load of a passing railway car. Such deflection may induce a safety risk due to quicker aging of the switch blades 141, 142 and rail segments 144, 143, as well as uneven railway track. Therefore, the displacement mechanisms 200 a, 201 a, 200 b, 201 b may advantageously be arranged to provide substantially continuous support to the switch blades 141, 142 and rail segments 144, 143 over a substantial length thereof, or to provide a plurality of individual load-carrying members distributed regularly or irregularly over the length thereof.
The displacement mechanisms 200 a, 201 a, 200 b, 201 b will consequently frequently exhibit an elongated shape with a length substantially exceeding the width thereof, when viewed from above. The direction of elongation of the displacement mechanisms 200 a, 201 a, 200 b, 201 b, i.e. their longitudinal orientation are schematically shown in FIG. 1 as extending substantially in the longitudinal direction L of the switch mechanism. This arrangement must be seen one example embodiment out of many alternative possible configurations. One advantageous alternative embodiment would for example be an arrangement where the longitudinal direction L of each displacement mechanisms 200 a, 201 a, 200 b, 201 b is oriented more aligned with the rail section it controls. With such an arrangement, each displacement mechanisms 200 b, 201 b of the switch frog would not be arranged in the longitudinal direction Las shown in FIG. 1, but instead be aligned with the first and second switch frog rail segments 144, 143 respectively.
Each of the first and second displacement mechanisms 200 a, 201 a, 200 b, 201 b may be located in a single individual casing 307 and be driven by first and second driving members 186, 187, respectively. The railway switch mechanism 100 may further comprise a single power source that simultaneously drives both the first and second driving members 186, 187. The single power source may for example be located in a power casing 185 that is common for the first and second displacement mechanisms 200 a, 201 a, 200 b, 201 b of each support frame.
Alternatively, a single power source may be used for each displacement mechanisms 200 a, 201 a, 200 b, 201 b, and the power source may be integrated into the casing 307 of each displacement mechanisms 200 a, 201 a, 200 b, 201 b.
Sleepers 303 are schematically included in FIG. 1 for improving comprehension of the invention but has no effect on the invention as such.
Many alternative configurations of the switch mechanism 100 are possible without leaving the scope of the invention. For example, the first and second support frames 160 a, 160 b may be interconnected by some connection device for ensuring that the relative position of the first and second support frame 160 a, 160 b does not change over time. Furthermore, a single support frame surrounding both the switch blades 141, 142 and the switch frog 150 may be implemented instead. Such a single support frame could for example be provided with at least two intermediate support frame walls extending in the transverse direction T for providing support for the displacement mechanism 200 a, 201 a, 200 b, 201 b and enabling elastic bending of the switch blades 141, 142 and switch frog rail segments 144, 143.
The functionality of the switch mechanism 100 will be described in relation to FIG. 1. By controlling the first and second switch blades 141, 142 such that only one of the switch blades 141, 142 is in the upper switch state while the other switch blade 141, 142 is in the lower switch state, switching of a railway wheel of a railway car approaching the switching mechanism 100 on the first pair of running tracks 110 can be performed, such that the railway car can be made to selectively follow either the first or second route A, B. For example, when it is desired that a railway car arriving to the switch mechanisms 100 on the first pair of running rails 110 should pass straight over the switch mechanisms 100 and continue along the first route A, the first switch blade 141 is displaced to its lower switch state and the second switch blade 142 is displaced to its upper switch state. Thereby, an inner flange of a left railway wheel of the railway car will not follow the first switch blade 141 simply because the flange passes above the first switch blade 141 and does consequently not come into contact with the first switch blade 141. Moreover, the right railway wheel is prevented from following the second outer rail 112 due to the inner flange of the right wheel contacting an inside surface the second switch blade 142. As a result, the left wheel of the railway car will continue along the first outer rail 111 and the right wheel will leave the second outer rail 112 and instead follow the second switch blade 142 towards the second closure rail 172.
In another example, when it is desired that a railway car arriving to the switch mechanisms 100 on the first pair of running rails 110 should diverge and continue along the second route B instead, the first switch blade 141 is displaced to its upper switch state and the second switch blade 142 is displaced to its lower switch state. Thereby, the inner flange of the left railway wheel of the railway car is forced to leave the first outer rail 111 and to follow the first switch blade 141 instead, while the right wheel will follow the second outer rail 112.
The switch frog 150 may be controlled to switch in accordance with the switch blades 141, 142. This means that the first switch frog rail segment 144 is controlled to be located in its upper switch state when the first switch blade 141 is controlled to be located in its upper switch state, and that the second switch frog rail segment 143 is controlled to be located in its upper switch state when the second switch blade 142 is controlled to be located in its upper switch state. This control arrangement, in combination with only allowing a single switch blade 141, 142 in the upper switch state at a time, ensures that the first rail segment 144 is in upper switch state when railway car is travelling towards the second route B, and that the second rail segment 143 is in the upper switch state when the railway car is travelling towards the first route A.
FIG. 2 shows an enlarged schematic top view of an example embodiment of the railway switch mechanism 100 of the first and second switch blades 141, 142. In this example embodiment the first support frame 160 a is made of two individual support frame sections 160 a 1, 160 a 2 that are arranged side-by-side with a mutual contact surface 180 that extends in a transverse direction T. Making the first support frame 160 a in sections 160 a 1, 160 a 2 enables simplified manufacturing, transportation and installation of the first support frame 160 a because of the smaller weight and size and of individual sections.
The two individual support frame sections 160 a 1, 160 a 2 may advantageously be secured together by fastening members for preventing that the individual sections become displaced from each other. In certain circumstance however, the support frame sections 160 a 1, 160 a 2 may merely be installed side-by-side and interconnected by means of the first and second outer rails 111, 112, first or second switch blades 141, 142, and first and second displacement mechanisms 200 a, 201 a.
Depending on the size the first support frame 160 a may alternatively be made three, four or even more individual support frame sections.
In the example embodiment of FIG. 2, each of the first and second displacement mechanisms 200 a, 200 b are located in two individual casings 307 a, 307 b that are arranged substantially aligned in a substantially longitudinal direction L and interconnected by a moveable driving member 188, 189. Forming each of the first and second displacement mechanisms 200 a, 200 b by two individual and functionally interconnected casings 307 a, 307 b offers the advantage of enabling replacement of only one casing in case of malfunction, thereby increasing the maintenance flexibility and reducing maintenance cost.
Moreover, if the support frame 160 a, 160 b is also made of two or more individual sections it is advantageous to also split the first and second displacement mechanisms 200 a, 200 b, 201 a, 201 b accordingly for enabling pre-mounting of the individual casings 307 a, 307 b on the individual support frame sections 160 a 1, 160 a 2, such that only placing and interconnection of pre-manufactured support frame sections 160 a 1, 160 a 2 is required when installing a railway switch mechanism.
The individual casings 307 a, 307 b may for example be secured to a bottom of the support frame 160 a, 160 b by means of a plurality of holding devices 190 that are arranged to clamp each individual casing 307 a, 307 b to the bottom of the support frame 160 a, 160 b.
The power casing 185 can for example be located either in front of or behind the one or more individual casings 307 a, 307 b of each of the first and second displacement mechanisms 200 a, 200 b in the longitudinal direction L. Alternatively, the power casing 185 can for example be located between two individual casings 307 a, 307 b in the longitudinal direction L
The railway switch mechanism 100 may further comprises elastic fill material 192 located between each of the first and second outer rails 111, 112 and an elevated portion 191 of the longitudinal side wall 162 a of the support frame 160 a, as seen in the transverse direction T, for providing improved lateral support to each of the first and second outer rails 111, 112. The improved lateral support to each of the first and second outer rails 111, 112 may be advantageous when the first and second outer rails 111, 112 are mounted on elastic rail pads that enable a certain degree of relative movement between the first and second outer rails 111, 112 and the underlying support frame 160 a. The elastic fill material 192 may be placed intermittently in a substantially longitudinal direction L for providing attachment spaces 193 between neighbouring fill material portions.
FIGS. 3a and 3b show schematically an example cross-section of the switch mechanism along line A-A in FIG. 1 with the switch mechanism in a first and second switch state, respectively. The first support frame 160 a is positioned on flat underlying ground surface 327 and is provided with a bottom 161 a, two longitudinal side walls 162 a and two transverse side walls (not showed) extending from the bottom upwards. An internal space 163 a is defined by said walls 162 a and bottom 161 a and the displacement mechanisms 200 a, 201 a are located within the internal space 163 a. Location of the displacement mechanisms 200 a, 201 a within the internal space 163 a has the advantage of allowing a more protected installation of the displacement mechanisms 200 a, 201 a against climate, debris, snow, ice, etc. Moreover, the support frame enclosure enables improved stability for displacement mechanisms 200 a, 201 a, and more cost-efficient heating of the displacement mechanisms 200 a, 201 a and switch blades 141, 142. It can be clearly seen that both the first and second outer rails 111, 112 are located on top of the longitudinal side walls 162 a.
A bottom side of the displacement mechanisms 200 a, 201 a must be directly or indirectly secured to the bottom 161 a of the support frame 160 a, and a top side of the displacement mechanisms 200 a, 201 a must be directly or indirectly secured to the switch blades 141, 142. Thereby, it is possible control the vertical position of each switch blade 141, 142 by means of the first and second driving members 186, 187.
Each of the first and second displacement mechanisms 200 a, 201 a are located in an individual casing 307 that has a first longitudinal side wall 317 facing the longitudinal side wall 162 a of the support frame 160 a, and an opposite second longitudinal side wall 318 facing the interior space 163.
An exterior protrusion 316 may be located in the first longitudinal side wall 317 of the casing 307 and protruding outwards in the transverse direction T. Furthermore, each substantially longitudinal side wall 162 a of the support frame 160 a may comprise at least one corresponding recess 319 located in a substantially longitudinal side wall of the support frame, such that each individual casing 307 can be secured to the support frame 160 a by means of the exterior protrusion 316 being positioned in the corresponding recess 319.
The exterior protrusion 316 of each individual casing 307 may further be prevented from escaping from the corresponding recess 319 by means of at least one threaded member 320 located near the second longitudinal side 318 of each individual casing 307 and arranged to clamp the casing 307 to the bottom 161 a of the support frame 160 a.
The at least one threaded member 320 may cooperate with holding devices 190 for securing the first and second displacement mechanisms 200 a, 201 a to a bottom of the support frame 160 a.
The switch blades 141, 142 may be fastened on a top side of the displacement mechanisms 200 a, 201 a, e.g. on top of the casing 307 by welding, clamping, or the like.
Each of the first and second displacement mechanisms 200 a, 201 a comprises a motion control arrangement configured for providing vertical displacement of an associated switch blade 141, 142 in response to horizontal displacement of a lower motion control member in a direction substantially parallel to a longitudinal direction of the first or second switch blade 141, 142. Consequently, depending on the design of the first and second displacement mechanisms 200 a, 201 a and the first and second switch blade 141, 142 more or less significant vertical forces will act on the lower motion control member. For example, if the first and second switch blades 141; 142 are bent elastically to switch from an upper switch state to a lower switch states by means of the motion control arrangement, significant lifting forces will act on the lower motion control arrangement in a lower switch state due to the switch blades 141, 142 that wants to return to their natural state.
Consequently, for avoiding that the lower motion control member becomes displaced in the vertical direction, the each of the first and second displacement mechanisms 200 a, 201 a may for example be provided with an interlocking groove and tongue arrangement 308 is arranged on a bottom side of the first and second displacement mechanisms 200 a, 201 a. The interlocking groove and tongue arrangement 308 may for example be arranged to have a bottom surface in horizontal sliding contact with an internal bottom surface of the casing 307 for enabling vertical load transfer from the switching blades 141, 142 to the casing 307 and further to the first support frame 160 a.
A first stationary outer rail 111 is located on one of the two longitudinal side walls 162 a of the first support frame 160 a and the second stationary outer rail 112 is located on the other of the two longitudinal side walls 162 a of the first support frame 160 a. Since the first and second stationary outer rails 111, 112 must be located very close the inner edge of the side wall 162 a of the first support frame for being able to cooperate with the first and second switch blades that are positioned on the first and second displacement mechanisms 200 a, 201 a, the conventional foot of the first and second stationary outer rails 111, 112 may have to be at least partly removed on the inner side of the rails 111, 112. However, removal of part of the foot may reduce the stability of the rail in the transverse direction T, and the risk for rail canting may increase.
For providing improved stability of the first and second stationary outer rails 111, 112 in the transverse direction T while still enabling the first and second stationary outer rails 111, 112 to be located very close the inner edge of the side wall 162 a of the first support frame 160 a, first and second stationary lateral support structures 325, 326 may be provided.
The first stationary lateral support structure 325 is attached to an interior side of side wall 162 a of the first support frame 160 a and located between the first stationary outer rail 111 and the first displacement mechanism 200 a and configured for providing lateral support to the first stationary outer rail 111. The second stationary lateral support structure 326 is attached to an interior side of the other side wall 162 a of the first support frame 160 a and located between the second stationary outer rail 112 and the second displacement mechanism 201 a and configured for providing lateral support to the second stationary outer rail 112.
Each of the first and second stationary lateral support structures 325, 326 may have integrally formed anchor elements 327 that are being cast-in with the material of the first support frame 160 a, such that a rigid, robust and reliable fastening of the first and second stationary lateral support structures 325, 326 is provided. Alternatively, the first and second stationary lateral support structures 325, 326 may be bolted to the interior side of a side wall 162 a of the first support frame 160 a by a threaded member, or the like.
A top portion 328 of each stationary lateral support structure 325, 326 extends upwards and in contact with a web portion 417 of the first or second stationary outer rail 111, 112, as will be described in more detail in with reference to FIG. 4.
In the shown example embodiment the first frame 160 a is provided with an electrical heating mechanism 420 a located near each of the first and second stationary lateral support structures 325, 326 and configured to heat the first frame 160 a. Moreover, an insulating layer 422 a may be provided on the outside of the first frame 160 a for reducing heat transfer to the surroundings and the cost for heating.
The first support frame 160 a is further provide with water draining channels 321 located between each of the first and second displacement mechanisms 200 a, 201 a and the associated longitudinal side wall 162 a of the first support frame 160 a for enabling draining of water 322 from the interior 163 a of the first support frame 160 a. Water 322 that may have entered between each of the first and second displacement mechanisms 200 a, 201 a and the associated longitudinal side wall 162 a of the first support frame 160 a is otherwise difficult to remove from the first support frame 160 a, and may cause corrosion and freeze to ice when not drained.
The first support frame 160 a may also be provide with central water draining channel 323 for draining water 322 that have entered a centre portion of the interior space 163 a.
As shown in FIGS. 3a and 3b , the elastic fill material 192 is located between each of the first and second outer rails 111, 112 and an elevated portion 191 of the longitudinal side wall 162 a of the support frame 160 a. The elastic fill material 192 is configured to provide improved lateral support to each of the first and second outer rails 111, 112.
The railway switch mechanism 100 further comprises a rail pad 329 of elastic material located between each of the first and second outer rails 111, 112 and the longitudinal side wall 162 a of the first support frame 160 a, as seen in the vertical direction V. The rail pad 329 enables a certain degree of motion of the first and second outer rails 111, 112 in the transverse direction T for reducing vibrations and noise. The first and second outer rails 111, 112 are otherwise fastened to the top surface of the first and second longitudinal side walls 162 a of the first support frame 160 a, for by means of conventional rail anchors.
Railway wheels 409, 411 of a railway car are illustrated in FIG. 3a in engagement with the first and second outer rails 111, 112, as well as the first second switch blade 142. In the illustrated first switching mode the first switch blade 141 is vertically displaced downwards a distance 310 well beyond the depth of the flange 412 of the left wheel 409, and the switch interconnects the first and third pair 110, 130 of running rails.
In the second switching mode illustrated in FIG. 3b the second switch blade 142 is vertically displaced downwards well beyond the depth of the flange 412 of the right wheel 411, and the switch interconnects the first and second pair 110, 120 of running rails.
The second support frame 160 b has substantially the same constructional design and features as the first support frame 160 a, in particular with respect to the overall design of the second support frame 160 b, fastening of the first and second displacement mechanisms 200 b, 201 b to the second support frame 160 b, the design and functionality of the first and second displacement mechanisms 200 b, 201 b, the interlocking groove and tongue arrangement, the heating mechanism, the water draining channels, etc.
However, since first and second displacement mechanisms 200 b, 201 b are located close to the switch frog 150 they are not necessarily secured to the longitudinal side walls 162 b of the second support frame 160 b, and the fastening of the first and second displacement mechanisms 200 b, 201 b is performed without the external protrusion and corresponding recess, as described with reference to the first support frame 160 a. Moreover, there is no need for any stationary lateral support structure because the first and second rail segments 144, 143 are nor positioned close the first and second outer rails 111, 112.
FIG. 4 shows schematically an example attachment of a first outer rail 111 to a first stationary lateral support structure 325. Only the upper portion of the first stationary lateral support structure 325, part of the longitudinal side wall 162 a and part of insulation 422 a of the first frame 160 a are illustrated in FIG. 4.
The first outer rail 111 comprises a railhead 418, a web portion 417 and a foot 419. The foot 491 has a flat downward facing bottom surface 433 that is configured to be placed on a flat upward-facing support surface for enabling transfer of vertical force from the first outer rail 111 to the underlying support structure, which here is represented by a rail pad 329 of elastic material.
Conventional rails have a foot with a foot portion extending both to the right and left from a centre of the rail for providing good stability against canting or kipping of the rail. However, as shown in FIG. 4, since the first stationary outer rails 111 must be located very close the inner edge 430 of the side wall 162 a of the first support frame 160 a for being able to cooperate with the first switch blade, the right foot portion of the first stationary outer rail 111 has been removed. For reducing the risk for canting or tipping of the first stationary outer rail 111 the railway mechanism comprises a first stationary lateral support structure 325 that is fixed to the first support frame 160 a and extends upwards and in contact with a web portion 417 of the first stationary outer rail 111 for providing additional lateral support to the first stationary outer rail 111.
The top portion 431 of the first stationary lateral support structure 325 that extends above the bottom surface 433 of the first stationary outer rail 111 and provides lateral support to the first outer rail 111 may for example extend over at least 20%, specifically at least 40%, and more specifically at least 60%, of the total height 432 of the first stationary outer rail 111 in the vertical direction V.
As described above, the railway switch mechanism 100 further comprises a rail pad 329 of elastic material located between the first outer rail 111 and a top surface of the longitudinal side wall 162 a of the first support frame 160 a. However, for achieving reduced noise and vibrations by means of the underlying rail pad 329 the attachment of the first outer rail 111 to the first stationary lateral support structure 325 must allow a certain degree of relative motion. An example embodiment attachment providing such relative motion is illustrated in FIG. 4.
The relative motion is accomplished by means of threaded member 437 or pin that is attached to the first stationary lateral support structure 325 and extends through a hole 438 in the web portion 417 with a play 434. The play 434 is preferably provided at least in the vertical direction V.
The play 434 is accomplished by having an external diameter 435 of the shank of threaded member 437 or pin that is about 5-70%, specifically 5-50% smaller than an internal diameter 439 of the hole 438 in the web portion 417.
The threaded member 437 or pin may be provided with a head 440 that abuts a side surface of the web portion 417. Moreover, the threaded member 437 or pin may for example be secured in a threaded or non-threaded hole 441 in the first stationary lateral support structure 325. Thereby an inner surface 442 of first stationary lateral support structure 325 may be flat and without protrusions that may interfere with the switch motion of the first switch blade and/or first displacement mechanism 200 a.
Alternatively, the threaded member 437 or pin may be welded or riveted to the first stationary lateral support structure 325. Still more alternatively, the threaded member 437 or pin that may be attached to the web portion 417 of the stationary outer rail 111 and extend through a hole in first stationary lateral support structure 325 with a play. Still more alternatively, the threaded member 437 or pin may be fasten the web portion 417 of the stationary outer rail 111 to the first stationary lateral support structure 325 using an external member, such as a threaded nut or the like, that is attached to the threaded member 437 or pin, while having a play between threaded member 437 or pin and holes of one or both of the web portion 417 and the first stationary lateral support structure 325 for enabling relative motion between the web portion 417 and the first stationary lateral support structure 325.
The example attachment described above with reference to FIG. 4 may also be provided between the second outer rail 112 and the second stationary lateral support structure 326.
FIGS. 5a and 5b show a schematic cross-section of a first example embodiment of a railway switch mechanism at cut B-B in FIG. 1 having the second switch blade 142 in an upper and lower switch state, respectively.
In FIG. 5a shows the second displacement mechanism 201 a is in an upper switch state and the second switch blade 142 extends substantially horizontally and in the same vertical position as the second closure rail 171. FIG. 5a further discloses the second displacement mechanisms 201 a located in a single casing 307.
In the example embodiment of FIGS. 5 and 5 b each displacement mechanism 201 a comprises two motion control arrangements 501 and four pairs of cooperating upper and lower load-carrying members 502, 503. Flowever, any number of motion control arrangements 501 and cooperating upper and lower load-carrying members 502, 503 may be used, depending on the circumstances of each specific application.
Each motion control arrangement 501 is configured for providing vertical displacement of the associated second switch blade 142 in response to horizontal displacement 506 of a lower motion control member 504.
Each pair of cooperating upper and lower load-carrying members 502, 503 are in contact with each other and configured to transmit load from the second switch blade 142 to the lower load-carrying member 503 via the upper load-carrying member 502 when the second switch blade 142 is in the upper switch state. However, each pair of cooperating upper and lower load-carrying members 502, 503 are also configured to be not in contact with each other at least partly along a displacement path of the upper and lower load-carrying members 502, 503 from the upper switch state, as shown in FIG. 5a , to the lower switch state, as shown in FIG. 5 b.
FIG. 5a illustrates the upper and lower load-carrying members 502, 503 in a first end position of said displacement path, and FIG. 5b illustrates the upper and lower load-carrying members 502, 503 in a second end position of said displacement path. Clearly, the upper and lower load-carrying members 502, 503 are in contact with each other in the first end position of the displacement path, as shown in FIG. 5a , and not in contact with each other in the second end position of the displacement path, as shown in FIG. 5 b.
An advantage of having each pair of cooperating upper and lower load-carrying members 502, 503 are in contact with each other in the upper switch state, and not in contact with each other at least partly along a displacement path of the upper and lower load-carrying members 502, 503 from the upper switch state to the lower switch state, is that the motion control functionality and load-carrying functionality can be separated to a greater extent.
This means that the motion control arrangement 501 can be designed and configured to be more specialised on the task of motion control of the switch blades 141, 142, and the pairs of cooperating upper and lower load-carrying members 502, 503 can be designed and configured to be more specialised on the task of load support to the switch blades 141, 142 in the upper switch state. Hence, each functionality can be more specialised and independent from each other, and the risk for a overdetermined displacement path is reduced.
For example, since the each pair of cooperating upper and lower load-carrying members 502, 503 can focus more on the load-carrying functionality in the upper switch state, and not even be in contact with other during part of the displacement path, they can be designed with a less complex shape, such as for example more block-shaped or trapezoid-shaped.
The second switch blade 142 may be fastened directly to the upper load-carrying members 502 and be cooperating directly with the lower motion control member 504 via an upper motion control member 507. However, for enabling a simplified installation of the switch mechanism 100, it may be advantageous to attach the second switch blade 142 to a second intermediate support member 214 a that is located between the second vertical displacement mechanism 201 a and the second switch blade 142. Thereby, the switch mechanism with the second vertical displacement mechanism 201 a may be pre-manufactured and placed on the ground at the desired position, and thereafter the second switch blade may be merely attached to an upper surface of the second intermediate support member 214 a, for example by rail anchors, welding, riveting, or the like.
The second intermediate support member 214 a may for example be made of metal. The second intermediate support member 214 a may also be connected to a transverse side wall 309 of the second casing 307 located at a heel end of the second switch blade 142, for example by means of a pivotal connection 178 a.
As schematically shown in FIGS. 5a and 5b the second intermediate support member 214 a may be made in two-parts, such that the second intermediate support member 214 a of the second switch blade 142 comprises a first part 510 and a second part 511. Each of the first and second parts 510, 511 defines a unique longitudinal portion of the second intermediate support member 214 a. A first side of the first part 510 may be connected to a transverse side wall 309 of the casing 307 by means of a pivotal connection 178 a and a second side of the first part 510 by may for example be pivotally connected to the second part 511 by means of a further pivot point 179 a.
A length of the first part 510 of the second intermediate support member 214 a in the longitudinal direction L may typically be less than the length of the second part 511 in the longitudinal direction L. The length of the first part 510 may for example be in the range of 30%-90% of the length of the second part 511.
Each part 510, 511 of the second intermediate support member 214 a is provided with an individual motion control arrangement 501. Depending on the length of the first and second parts 510, 511 more than one individual motion control arrangement 501 may be required for one of both parts 510, 511 for ensuring correct and reliable vertical displacement of the first and second parts 510, 511.
An advantage of having the second intermediate support member 214 a made in two interconnected parts is that the second intermediate support member 214 a is still secured to a transverse side wall 309 of the second casing 307, for example by means of the pivotal connection 178 a, such that a relatively safe and reliable displacement of the second intermediate support member 214 a is provided, while simultaneously enabling the second intermediate support member 214 a to have, over a relatively long effective length L2, a sufficiently lowered vertical position for allowed the wheel flange of the railway wheel to pass over, as shown in FIG. 5b . This design thus enables a relatively large vertical displacement over a relatively large length in the longitudinal direction L.
In the example embodiment of FIGS. 5a and 5b vertical switch movement of the second switch blade 142 is enabled by having a second switch blade 142 that is made integral with the second stationary closure rail 171 and designed to rely on elastic deformation (bending) in the vertical direction V for accomplishing the desired vertical displacement during switching motion between an upper and lower switch state. Due to the gradual elastic deflection of the continuous rail forming the second closure rail 171 and second switch blade 142 there is no clear location where the second closure rail 171 transforms into the second switch blade 142. The elastic deflection properties and final shape of the second switch blade 142 in the low switch state depends on many parameters, such as rail dimensions, rail material, frame design, vertical displacement mechanisms design, etc. Possibly, the bending will start adjacent the transverse side wall 309 of the second casing 307 because the rail is mechanically deflected downwards only within the first frame 160 a and not in the region of the second closure rail 171.
Alternatively, the second switch blade 142 according to the embodiment of FIGS. 5a and 5b may be composed of two individual parts, namely a first individual and separate part that is pivotally connected to the second closure rail 171 by means of a first hinged joint located at or near an end of the second closure rail 171, close or at the pivotal connection 178 a, and second individual and separate part that is pivotally connected to the first part by means of a second hinged joint located at or near said further pivot point 179 a, wherein a free end of the second switch blade 142 is located on an end of the second part opposite to the second hinged joint.
The motion control arrangement 501 comprises a lower and an upper motion control member 504, 507 that are configured to interact for translating a substantially horizontal displacement 506 of the lower motion control member 504 to a substantially vertical displacement of the upper motion control member 507. And since the upper motion control member 507 is directly or indirectly fastened to the second switch blade 142, the second switch blade 142 can be selectively positioned in an upper or lower switch state merely by horizontal displacement of the lower motion control member 504.
As shown in FIGS. 5a and 5b , the lower motion control member is configured to be displaced a direction substantially parallel to a longitudinal direction L of the second switch blade 142. This enables a plurality of the lower motion control members 504 to be interconnected and displaced simultaneously by means of a single driving member 187.
Furthermore, by also in connecting the lower motion control member 504 with the lower load-carrying members 503 the horizontal displacement of the lower motion control member 504 in the longitudinal direction L automatically results in identical horizontal displacement of the lower load-carrying members 503. This is advantageous because this arrangement results in automatic relative horizontal displacement between the load-carrying surfaces of the upper and lower load-carrying members 502, 503, such that lowering of the associated second switch blade 142 from the upper switch state to the lower switch state is enabled.
Interconnection of the lower motion control member 504 with the lower load-carrying members 503 may for example be realised by attaching the lower motion control member 504 and the lower load-carrying members 503 to a longitudinally moveable driving device 512 that is part of the second displacement mechanism 201 a. Common longitudinal displacement of the lower motion control member 504 and the lower load-carrying members 503 may subsequently be performed by simply connecting the driving device 512 to the second driving member 187.
The longitudinally moveable driving device 512 may for example be slidably attached to a bottom of the casing 307 by means of an interlocking groove and tongue arrangement 308 as described above with reference to FIGS. 3a and 3b , thereby avoiding that the driving device 512 and the thereto attached lower motion control member 504 and lower load-carrying members 503 becomes displaced in the vertical direction V. The driving device 512 may be made of a single metal plate.
The motion control arrangement 501 may have many alternative configurations for providing the desired vertical displacement of an associated second switch blade 142 in response to horizontal displacement of the lower motion control member 504. One example embodiment is disclosed in FIGS. 5a and 5b , wherein the lower motion control member 504 comprises guide track 513 with an inclined sliding surface that is configured to interact with a guide member in form of a shaft 514 of the upper motion control member 507. The shaft 514 is rigidly connected to the upper motion control member 507, and the shaft 514 is configured to be located in and to follow the guide track 513.
In the example embodiment of FIGS. 5a and 5b the guide track 513 has a horizontal section 515 that enables the cooperating upper and lower load-carrying members 502, 503 to also have horizontal mutual abutment surfaces, and an inclined section 516 that cooperates with the shaft 514 to ensure that the upper motion control member 507, and thus also the second switch blade 142, is vertically displaced to lower switch state upon longitudinal displacement of the lower motion control member 504. The inclined section 516 may for example have an inclination in the range of about 5-30 degrees from a longitudinal direction L.
FIGS. 6a and 6b show a schematic cross-section of a second example embodiment of a railway switch mechanism in a cut similar to that of FIGS. 5a and 5b and having the second switch blade 142 in an upper and lower switch state, respectively. According to this example embodiment the second intermediate support member 214 a is made in one-part.
Thereby a less complex design of the switch mechanism is enabled compared with the example embodiment of FIGS. 5a and 5 b.
The second switch blade 142 may be elastically bendable in the vertical direction V for enabling the vertical switch movement of the second switch blade 142, as illustrated in FIGS. 6a and 6b . Alternatively, as illustrated in FIG. 6c , the second switch blade 142 may be an individual part that is separate from and pivotally connected to the second closure rail 171 by means of a hinged joint 178 b located at or near an end of the second closure rail 171.
A first side of the single-part second intermediate support member 214 a may for example be pivotally connected to the transverse side wall 309 of the casing 307 by means of a pivotal connection 178 a, such that a relatively safe and reliable displacement of the second intermediate support member 214 a is provided, and a second side of the single-part second intermediate support member 214 a may be free to move in the vertical direction V and controlled by the motion control arrangement of the second displacement mechanisms 201 a.
Depending on the length of the second intermediate support member 214 a, the single-piece second intermediate support member 214 a may also result in reduced bending stress of the second switch blade 142 due to reduced bending per length of the switch blade 142. However, a single-piece second intermediate support member 214 a may for the same reason also result in reduced effective length L2 having a sufficiently lowered vertical position of the second switch blade 142 for allowing a wheel flange of the railway wheel to pass over, as shown in FIG. 5 b.
In the example embodiment of FIGS. 6a and 6b each displacement mechanism 201 a comprises a single motion control arrangement 501 and four pairs of cooperating upper and lower load-carrying members 502, 503. A single motion control arrangement 501 may be advantageous for avoiding an over-controlled vertical displacement motion of the single-part second intermediate support member 214 a when pivotally attached to the casing 307. A plurality of motion control arrangements 501 may however be advantageous in terms of controllability of the deflection of the switch blade over the length of the switch blade 142, if this is desired. This controllability may for example be used for avoiding that the switch blade does not deform plastically at any specific point. Moreover, any number of cooperating upper and lower load-carrying members 502, 503 may be used, depending on the circumstances of each specific application.
The shape and form of the cooperating upper and lower load-carrying members 502, 503 may be varied in all of the disclosed embodiments of the present disclosure, depending on the circumstances of each specific application. For example, one or both of the cooperating upper and lower load-carrying members 502, 503 may have chamfered or rounded corners 502′, 503′, as described more in detail with reference to FIGS. 8 and 9.
FIGS. 7a and 7b show a schematic cross-section of a third example embodiment of a railway switch mechanism in a cut similar to that of FIGS. 5a and 5b and having the second switch blade 142 in an upper and lower switch state, respectively.
According to this example embodiment the second intermediate support member 214 a is made in one-part, but contrary to the example embodiment of FIG. 6a, 6b , the second switch blade 142 is not elastically bent in the vertical direction V for enabling the vertical switch movement of the second switch blade 142, as illustrated in FIGS. 6a and 6b . Instead, the second switch blade 142 is vertically translatory moveable between the upper and lower switch state for enabling the vertical switch movement of the second switch blade 142.
Vertically translatory moveable between the upper and lower switch state means that the entire second switch blade 142 is displaced in the vertical direction while keeping its angular orientation. In other words, the switch blade is displaced in a uniform motion in the vertical direction. The entire second switch blade 142 thus has a horizontal orientation both in the upper and lower switch state. In other words, both longitudinal ends of the second switch blade 142 are vertically displaced with substantially the same length upon switching motion between the upper and lower switch state.
As illustrated in FIGS. 7a and 7b , at least two motion control arrangements 501 that are longitudinally offset from each other are typically required for providing the desired vertically translatory displacement of the second switch blade 142 between the upper and lower switch state. Moreover, even of five pairs of cooperating upper and lower load-carrying members 502, 503 are shown in FIGS. 7a and 7b , it is clear that any number of cooperating upper and lower load-carrying members 502, 503 may be used, depending on the circumstances of each specific application.
Since the second switch blade experience substantially no bending stress the risk for damages due to material fatigue is significantly reduced. Moreover, the total length of the second switch blade 142 in the longitudinal direction L can by significantly reduced because the effective length L2 of the second switch blade 142 with respect to sufficiently lowered vertical position is increased in relation to the total length of the switch blade. In fact, using translatory moveable switch blades or switch frog rail segments means that the entire length of the second switch blade 142 is an effective length L2 with respect to sufficiently lowered vertical position. Since the total length of the second switch blade 142 in the longitudinal direction L can by significantly reduced by means of vertical translatory motion of the second switch blade 142 between the upper and lower switch states, this design may be advantageous when there is only little space available.
Since the second switch blade 142 is not an integral part of, or pivotally attached to, the second closure rail 171, one or more guiding devices may be required for guiding the second switch blade 142 while being vertically translated between the upper and lower switch states. When the second vertical displacement mechanism 201 a is provided with a second intermediate support member 214 a, as illustrated in FIGS. 7a and 7b , the second switch blade 142 may be fastened to the second intermediate support member 214 a, for example by welding or rail anchors, and one or more guiding devices may be required for guiding the second intermediate support member 214 a between the upper and lower switch states. For example, at least one guiding device in form of a vertically oriented guide track located in the casing 307 may be configured to interact with a steering pin located on the second intermediate support member 214 a, or oppositely, may be used.
FIG. 8 shows schematically a side view of an example embodiment of a pair of cooperating upper and lower load-carrying members in a load transmitting state, in which a downward-facing load-carrying surface 801 of the upper load-carrying member 502 contacts and enables vertical load transmission from an associated switch blade or switch frog rail segment to the upward-facing load-carrying surface 802 of the at the lower load-carrying member 503.
The transitional edge 503′ between the upward-facing load-carrying surface 802 and a neighbouring side surface 803 of the lower load-carrying member 503 is rounded for enabling a more smooth and frictionless engagement between the cooperating upper and lower load-carrying members 502, 503 when shifting from a mutual non-contact state to a mutual contact state, upon approaching the upper switch state along the displacement path from lower switch state to the upper switch state. Without such a rounded transitional edge 503′ there is a risk that a vertical side surface 803 of the lower load-carrying members 503 contacts a vertical side surface 804 of the upper load-carrying member 502 when shifting from a mutual non-contact state to a mutual contact state, such that undesired interference may occur between the cooperating upper and lower load-carrying members 502, 503.
In the example embodiment of FIG. 8 only the lower load-carrying member 503 has a rounded transitional edge 503′. Alternatively, the transitional edge 502′ between the downward-facing load-carrying surface 801 and a neighbouring side surface 804 of the upper load-carrying member 502 may be rounded for enabling a more smooth and frictionless engagement between the cooperating upper and lower load-carrying members 502, 503. Still more alternatively, both the upper and lower load-carrying members 502, 503 may have rounded transitional edges 502′, 503′, as illustrated in FIGS. 6a and 6b . Still more alternatively, the transitional edge or edges 502′, 503′ may be chamfered instead, as schematically illustrated in FIG. 9. The exact form of the rounded or chamfered transitional edge or edges 502′, 503′ may be varied to best fit the specific circumstances.
FIG. 10a shows schematically a 3-D view of an example embodiment of a pair of cooperating upper and lower load-carrying members 502, 503 comprising a locking arrangement, and FIG. 10b shows schematically a cross-section of the pair of cooperating upper and lower load-carrying members 503, 503 of FIG. 10a . The first and second switch blades 141, 142 and/or the first and second switch frog rail segments 143, 144 must, when located in the upper switch state, be able to withstand very high loads in the vertical direction V when a rail vehicle is passing over the switch mechanism 100, but due to the speed of the railway vehicle also loads acting the transverse direction T. For improving stability and security of the first and second switch blades 141, 142 and/or the first and second switch frog rail segments 143, 144 in the upper switch state, at least one pair of cooperating upper and lower load-carrying members 502, 503 may comprise a locking arrangement 820 for mutually interlocking the upper and lower load-carrying members 502, 503 in the upper switch state for preventing relative vertical and transverse motion between the upper and lower load-carrying members 502, 503 in the upper switch state.
The locking arrangement 820 may for example include a channel 821 located in the upper load-carrying member 502 and extending the in longitudinal direction L, and corresponding protrusion 822 located in the lower load-carrying member 503. By having the channel 821 extending the in longitudinal direction L the corresponding protrusion 822 may automatically enter the channel 821 when the upper and lower load-carrying members 502, 503 are approaching each other during displacement from the lower switch state to the upper switch state. Moreover, by means of the longitudinal extension of the channel 821 the upper and lower load-carrying members 502, 503 may be interlocked at least in the transverse direction T. According to an alternative, the channel 821 may be located in the lower load-carrying member 503 and the corresponding protrusion 822 may be located in the upper load-carrying member 502.
The channel 821 may have an undercut recess 823 and the protrusion 822 may have an enlargement adapted to be interlockingly connectable with the channel and recess, such that vertical separation of the upper load-carrying member 502 from the lower load-carrying member 503 is prevented. This is accomplished by having a larger internal dimension of the channel 821 in the region of the undercut recess 823 than in a region of the opening of the channel 821, and by having a larger external dimension of the protrusion 822 in the region of the enlargement than in the region of the foot of the protrusion. Thereby, the upper and lower load-carrying members 502, 503 may be interlocked also in the vertical direction V.
FIG. 10c shows schematically a side view of an alternative example embodiment of a locking arrangement 820 for a pair of cooperating upper and lower load-carrying members 502, 503. In this example embodiment the locking arrangement 820 includes a channel 821 located in the lower load-carrying member 503 and extending the in transverse direction T, and corresponding protrusion 822 located in the lower load-carrying member 503. By having the protrusion 822 protruding in the longitudinal direction L and having an opening of the channel facing an opposite direction, the protrusion 822 may automatically enter the opening of the channel 822 when the upper and lower load-carrying members 502, 503 are positioned in the upper switch state. Thereby, the upper and lower load-carrying members 502, 503 may be interlocked also in the longitudinal and vertical direction L, V.
As shown above with reference to FIGS. 6a, 6b , 8 and 9, the risk for undesirable interference between the upper and lower load-carrying members 502, 503 when entering an overlapping condition of the load-carrying surfaces of the upper and lower load-carrying members 502, 503 may be reduced by rounded or chamfered corners upper and lower load-carrying members 502, 503. An alternative solution to this problem is provided by configuring the motion control arrangement, for enabling a vertical switch movement of the first or second switch blade 141, 142 or first or second switch frog rail segment 143, 144 from the lower switch state to the upper switch state, to first provide upward vertical displacement of an associated switch blade 141, 142 or switch frog rail segment 143, 144 beyond the upper switch state, such that a downward-facing load-carrying surface of an upper load-carrying member is located vertically offset from a upward-facing load-carrying surface of a lower load-carrying member, and subsequently providing downward vertical displacement of the associated switch blade 141, 142 or switch frog rail segment 143, 144 to the upper switch state, in which the downward-facing load-carrying surface of the upper load-carrying member contacts and enables load transmission from the associated switch blade 141, 142 or switch frog rail segment 143, 144 to the upward-facing load-carrying surface of the at the lower load-carrying member.
By means of the vertical offset between the downward-facing load-carrying surface of an upper load-carrying member and the upward-facing load-carrying surface of a lower load-carrying member when said load-carrying surfaces are entering an overlapping condition in the vertical direction V, an undesired interference between the upper and lower load-carrying members 502, 503 is prevented.
One example embodiment for configuring the motion control arrangement to first provide upward vertical displacement of an associated switch blade 141, 142 or switch frog rail segment 143, 144 beyond the upper switch state, and subsequently providing downward vertical displacement of said switch blade 141, 142 or switch frog rail segment 143, 144, is illustrated in FIG. 11a . Here, the lower motion control member 504 comprises a guide track 513 that has a first inclined section 516 a and a second inclined section 516 b, wherein a portion of the guide track that interconnects the first and second inclined sections 516 a, 516 b is located generally above the first and second inclined sections 516 a, 516 b. On other words, the first and second inclined sections 516 a, 516 b jointly define a curved path having centre portion of the curved path located above the end points of the curved path.
The curved path with downward-oriented first and second inclined sections 516 a, 516 b towards each longitudinal side of the lower motion control member 504 provides the desired upward vertical displacement of an associated switch blade 141, 142 or switch frog rail segment 143, 144 beyond the upper switch state, and subsequent downward vertical displacement of said switch blade 141, 142 or switch frog rail segment 143, 144, when switching from a lower switch state to an upper switch state.
The level of inclination of each of the first and second inclined sections 516 a, 516 b may for example be in the range of about 5-30 degrees from a horizontal direction.
The first and second inclined sections 516 a, 516 b may be interconnected by a horizontal section 515 of the guide track 513, as shown in FIG. 11a . The intermediate horizontal section 515 enables a smoother transition for the guide member when moving along the guide track 513 from one to the other of the first and second inclined sections 516 a, 516 b.
Many alternative design possibilities are available for providing the desired upward vertical displacement of an associated switch blade 141, 142 or switch frog rail segment 143, 144 beyond the upper switch state, and subsequent downward vertical displacement of said switch blade 141, 142 or switch frog rail segment 143, 144. For example, the intermediate horizontal section 515 may be reduced or even completely deleted, and inclination levels of the first and second inclined sections 516 a, 516 b may be varied and not the same. Moreover, the guide track 513 may have a more curved curvilinear shape with less distinct transitions between the various sections 516 a, 516 b, 515 of the guide track, as shown in FIG. 1 ib.
FIG. 12a-12d shows a displacement path of a pair of cooperating upper and lower load-carrying members 502, 503 and a motion control arrangement 501 from a lower switch state to an upper switch state of the second displacement mechanism 201 a.
In FIG. 12a the second displacement mechanism 201 a is in the lower switch state. The upper and lower load-carrying members 502, 503 are not in contact with each other. At least the load-carrying surfaces 801, 802 of the upper and lower load-carrying members 502, 503 are offset from each other in the longitudinal direction L and not in a vertically overlapping state with each other. The downward-facing load-carrying surface 801 of the upper load-carrying member 502 is located a distance L3 below the upward-facing load-carrying surface 802 of the lower load-carrying member 503. The guide member 514 is located in an end-region of the first inclined section 516 a of the guide track 513.
When the longitudinally moveable driving device 512 is pushed by a driving member (not showed) to move along the longitudinal direction L, as illustrated by arrow 831, the guide member 514 will start to move along the guide track 513, such that the motion control arrangement 501 will push the second intermediate support member 214 a, the upper load-carrying member 502 and the associated second switch blade (not showed) upwards in the vertical direction, as illustrated by arrow 832. Simultaneously, the lower load-carrying member 503 will follow the longitudinally moveable driving device 512 and start to move in the longitudinal direction, such that the upper and lower load-carrying members 502, 503 start to approach each other in the longitudinal direction L.
In FIG. 12b the guide member 514 has reached a transition between the horizontal section 515 and the first inclined section 516 a of the guide track 513. In this position the second intermediate support member 214 a and the associated second switch blade have been vertical displaced to a position beyond the upper switch state, i.e. a position that is located vertically above the position in which the associated second switch blade is ready for carrying and switching a railway vehicle past the railway switch mechanism. This is also seen in that the downward-facing load-carrying surface 801 of the upper load-carrying member 502 is located vertically above and offset a distance L4 from the upward-facing load-carrying surface 802 of a lower load-carrying member 502. Moreover, at least the load-carrying surfaces 801, 802 of the upper and lower load-carrying members 502, 503 are still offset from each other in the longitudinal direction Land not in a vertically overlapping state with each other.
In FIG. 12c the guide member 514 has reached a transition between the horizontal section 515 and the second inclined section 516 b of the guide track 513. In this position the second intermediate support member 214 a and the associated second switch blade are still vertically displaced to a position beyond the upper switch state. However, due the continuous motion of the longitudinally moveable driving device 512 and associated lower load-carrying member 503 in the longitudinal direction, the load-carrying surfaces 801, 802 of the upper and lower load-carrying members 502, 503 are partly in a vertically overlapping state with each other. Due to the fact that the downward-facing load-carrying surface 801 of the upper load-carrying member 502 has been located vertically above and offset a distance L4 from the upward-facing load-carrying surface 802 of a lower load-carrying member 502 during the transition from a non-overlapping state to a partly overlapping state of the load-carrying surfaces 801, 802 of the upper and lower load-carrying members 502, 503, any undesirable interference between the upper and lower load-carrying members 502, 503 are avoided. Undesirable interference between the upper and lower load-carrying members 502, 503 can for example result in jamming of or damage to the displacement mechanism.
If even further security against undesirable interference is desired the one or both of the upper and lower load-carrying members 502, 503 can be provided with rounded or chamfered transitional edges between the upward-facing load-carrying surface 802 and a neighbouring side surface of the lower load-carrying member 503, as described above with reference to FIGS. 8 and 9.
In FIG. 12d the longitudinally moveable driving device 512 has been pushed along the longitudinal direction L, as illustrated by arrow 831, to an end position, and the motion control arrangement 501 has lowered the second intermediate support member 214 a, the upper load-carrying member 502 and the associated second switch blade (not showed) in the vertical direction, as illustrated by arrow 833. Thereby, the second displacement mechanism 201 a has arrived in the upper switch state. The upper and lower load-carrying members 502, 503 are in contact with each other and ready for transmitting load from the switch blade an underlying support surface. The load-carrying surfaces 801, 802 of the upper and lower load-carrying members 502, 503 are substantially aligned with each other in the longitudinal direction L and in a vertically overlapping state with each other. The guide member 514 is located in an end-region of the second inclined section 516 b of the guide track 513.
The motion control arrangement 501 can take many different shapes and designs for providing the vertical displacement of an associated switch blade 141, 142 or switch frog rail segment 143, 144 in response to horizontal displacement of at least one lower motion control member. For example, as illustrated in FIGS. 13a and 13b which show a fourth example embodiment of the motion control arrangement 501 in an upper and lower switch state, respectively, the guide member 514 of the upper motion control member 507 may be a roller or wheel that travels along a guide track 513 of the lower motion control member 504.
Still more alternatively, FIG. 14a-14b shows of a fifth example embodiment of a motion control arrangement 501 in an upper and lower switch state, respectively, wherein the motion control arrangement 501 comprises a set of rigid linkage members that are pivotally attached to the second intermediate support member 214 a, an underlying stationary support surface such as the casing 307 and the longitudinally moveable driving device 512.
For example, a first end of first rigid linkage member 841 is pivotally connected to the second intermediate support member 214 a at a first pivot point 840, a first end of a second rigid linkage member 842 is pivotally connected to the casing 307 at a second pivot point 844, a first end of a third rigid linkage member 843 is pivotally connected to the longitudinally moveable driving device 512 at a third pivot point 845, and a second end of each of the first to third rigid linkage members 841-843 are interconnected to each other at a fourth pivot point 846.
The first and second rigid linkage members 841, 842 jointly control the vertical position of the second intermediate support member 214 a by means of varying a relative angle between the first and second rigid linkage members 841, 842. Moreover, said relative angle is controlled by the longitudinally moveable driving device 512, which is connected to the fourth pivot 846 via the third rigid linkage member 843.
The combined length of the first and second rigid linkage members 841, 842 may be set to be larger than the distance between the first and second pivot points 840, 844 in the upper switch state. Thereby, initial motion of the longitudinally moveable driving device 512, which is connected to the fourth pivot 846 via the third rigid linkage member 843, in a direction that will cause the first and second rigid linkage members 841, 842 to be arranged parallel with each other, will inherently result in upwards vertical displacement of the second intermediate support member 214 a, prior to initiating a vertical lowering displacement towards the lower switch state. This configuration may consequently be used for enabling the cooperating upper and lower load-carrying members 502, 503 to have horizontal mutual abutment surfaces 801, 802, and reducing the risk for undesirable interference between the upper and lower load-carrying members 502, 503 during relative motion between the upper and lower switch states.
FIG. 15a-15b shows a schematic cross-section of a sixth example embodiment the motion control arrangement in an upper and lower switch state, respectively. The motion control arrangement 501 comprises a single rigid linkage member 850. A first and of the single rigid linkage member 850 is pivotally attached to the second intermediate support member 214 a at a first pivot point 851, and a second end of the single rigid linkage member 850 is pivotally connected to the longitudinally moveable driving device 512 at a second pivot point 852.
The single rigid linkage member 850 controls the vertical position of the second intermediate support member 214 a by means of varying the degree of inclination of the single rigid linkage member 850 relative to the vertical direction V. Moreover, by having a longitudinal offset between the first pivot point 851 and second pivot point 852 in the upper switch state, and initially moving the longitudinally moveable driving device 512 in a direction that will cause a reduction of the longitudinal offset between the first and second pivot points 851, 852, the second intermediate support member 214 a will inherently be displaced upwards in the vertical direction prior to initiating a vertical lowering displacement towards the lower switch state. This configuration may consequently be used for enabling the cooperating upper and lower load-carrying members 502, 503 to have horizontal mutual abutment surfaces 801, 802, and reducing the risk for undesirable interference between the upper and lower load-carrying members 502, 503 during relative motion between the upper and lower switch states.
FIGS. 16a and 16b show a schematic cross-section of a seventh example embodiment of a railway switch mechanism in a cut similar to that of FIGS. 7a and 7b and having the second switch blade 142 in an upper and lower switch state, respectively.
According to this example embodiment the second switch blade 142 is vertically translatory moveable between the upper and lower switch state for enabling the vertical switch movement of the second switch blade 142.
As illustrated in FIGS. 16a and 16b , at least two motion control arrangements 501 that are longitudinally offset from each other may be provided for enabling the desired vertically translatory displacement of the second switch blade 142 between the upper and lower switch state. However, this example embodiment comprise at least two pairs of wedge-shaped cooperating upper and lower load-carrying members 502, 503 that assist the motion control arrangements 501 in moving the second switch blade 142 between the upper and lower switch state.
In particular, the wedge-shaped cooperating upper and lower load-carrying members 502, 503 may be designed to assist the motion control arrangements 501 in lifting the second switch blade 142 from the lower switch state to the upper switch state.
In the example seventh embodiment of FIGS. 16a and 16b the upper load-carrying member 502 is directly or indirectly permanently attached to the second switch blade 142 and comprises an inclined wedge-surface 165 facing downwards that is in contact with an inclined upwards facing wedge-surface 166 of the lower load-carrying member 503.
The downwards facing inclined wedge-surface 165 of the upper load-carrying member 502 has the same angle of inclination 167 as the angle of inclination 168 of the upwards facing wedge-surface 166 of the lower load-carrying member 503, such that axial displacement of the lower load-carrying member 503 results in vertical displacement of the upper load-carrying member 502.
The angle of inclination 167, 168 of the inclined wedge- surfaces 165, 166 is preferably identical with angle of inclination 169 of the guide track 513 for enabling said wedge- surfaces 165, 166 remain in contact with each other during the relative displacement.
One advantage of having wedge-shaped cooperating upper and lower load-carrying members 502, 503 is that the wedge-shaped cooperating upper and lower load-carrying members 502, 503 is that the risk for interference between the cooperating upper and lower load-carrying members 502, 503 during the relative motion is reduced, because the downwards facing inclined wedge-surface 165 of the upper load-carrying member 502 are in contact with each other over the entire relative displacement motion. Thereby, a higher operational reliability may be obtained.
The angle of inclination 167, 168 of the inclined wedge- surfaces 165, 166 may for example be in range of 5-40 degrees, specifically in the range of 10-30 degrees.
A part of the downwards facing surface of the upper load-carrying member 502 located longitudinally sideways from the downwards facing inclined wedge-surface 165 may have a substantially horizontal orientation (not showed), and a corresponding part of the upwards facing surface of the lower load-carrying member 503 located longitudinally sideways from the upwards facing inclined wedge-surface 166 may have a substantially horizontal orientation (not showed), such that transmittal of vertical force from the upper load-carrying member 502 to the lower load-carrying member 503 in the upper switch state without incurring any longitudinal force component acting to displace the lower load-carrying member 503 in the longitudinal direction Lis enabled.
The upper and lower inclined wedge- surfaces 165, 166 may have cooperating tracks for improving stability and reliability during their relative motion.
The cooperating tracks may for example be formed of a protrusion in one of the upper and lower inclined wedge- surfaces 165, 166 and a corresponding recess in the other of upper and lower inclined wedge- surfaces 165, 166. Thereby relative displacement in the transverse direction T is prevented.
The cooperating tracks may even be formed of an undercut recess in one of the upper and lower inclined wedge- surfaces 165, 166 and a corresponding protrusion in the other of upper and lower inclined wedge- surfaces 165, 166. Thereby relative displacement in the transverse direction T is prevented while additionally ensuring that the upper and lower inclined wedge- surfaces 165, 166 remain in contact.
In particular, the cooperating undercut recess and protrusion in the upper and lower inclined wedge- surfaces 165, 166 may de designed to assist the motion control arrangements 501 in lowering the second switch blade 142 from the upper switch state to the lower switch state, because the cooperating undercut recess and protrusion prevents the cooperating upper and lower load-carrying members 502, 503 from becoming disengaged from each other
In the example seventh embodiment the longitudinally moveable driving device 512 comprises a plurality of individual rigid connection elements that interconnect neighbouring lower motion control members 504 and lower load-carrying members 503. Thereby, a single longitudinally moveable driving device 512 located under the lower load-carrying members 503 can be omitted, such that a more compact design of the casing 307 can be provided.
Each lower motion control members 504 and lower load-carrying member 503 may for example be slidably attached to a bottom of the casing 307 by means of an interlocking groove and tongue arrangement 308 as described above with reference to FIGS. 3a and 3b , or a similar arrangement, thereby avoiding that lower motion control members 504 and lower load-carrying members 503 becomes displaced in the vertical direction V.
Alternatively, the design of the longitudinally moveable driving device 512 described with reference to FIGS. 5a and 5b may be used also in the embodiment of FIGS. 16a and 16b . Correspondingly, the design of the longitudinally moveable driving device 512 described with reference to FIGS. 16a and 16b may of course be implemented in any of the embodiments described in FIGS. 5a-7a and 12a -15 a.
FIGS. 17a and 17b show a schematic cross-section of an eight example embodiment of a railway switch mechanism in a cut similar to that of FIGS. 7a and 7b and having the second switch blade 142 in an upper and lower switch state, respectively.
According to this example embodiment the second switch blade 142 is vertically translatory moveable between the upper and lower switch state for enabling the vertical switch movement of the second switch blade 142.
As illustrated in FIGS. 17a and 17b , this embodiment does not exhibit individual motion control arrangement and individual pairs of cooperating upper and lower load-carrying members. Instead, each displacement mechanism 201 a merely comprises a plurality of pairs of cooperating wedge-shaped upper and lower load-carrying members 502, 503, each of which is designed to provide both vertical displacement of an associated switch blade in response to horizontal displacement of the driving device 512 and load transmission from the associated switch blade to the casing 307 when the associated switch blade or switch frog rail segment is in the upper switch state. In other words, each of the plurality of pairs of cooperating upper and lower load-carrying members 502, 503 provide both motion control functionality and load-carrying functionality.
In the eight example embodiment of FIGS. 17a and 17b the upper load-carrying member 502 is directly or indirectly permanently attached to the second switch blade 142 and comprises an inclined wedge-surface 165 facing downwards that is in contact with an inclined upwards facing wedge-surface 166 of the lower load-carrying member 503.
The downwards facing inclined wedge-surface 165 of the upper load-carrying member 502 has the same angle of inclination 167 as the angle of inclination 168 of the upwards facing wedge-surface 166 of the lower load-carrying member 503, such that axial displacement of the lower load-carrying member 503 results in vertical displacement of the upper load-carrying member 502.
One advantage of having wedge-shaped cooperating upper and lower load-carrying members 502, 503 is that the wedge-shaped cooperating upper and lower load-carrying members 502, 503 is that the risk for interference between the cooperating upper and lower load-carrying members 502, 503 during the relative motion is reduced, because the downwards facing inclined wedge-surface 165 of the upper load-carrying member 502 are in contact with each other over the entire relative displacement motion. Thereby, a higher operational reliability may be obtained.
The angle of inclination 167, 168 of the inclined wedge- surfaces 165, 166 may for example be in range of 5-45 degrees, specifically in the range of 10-30 degrees. A part 176 of the downwards facing surface of the upper load-carrying member 502 located longitudinally sideways from the downwards facing inclined wedge-surface 165 may have a substantially horizontal orientation, and a corresponding part 177 of the upwards facing surface of the lower load-carrying member 503 located longitudinally sideways from the upwards facing inclined wedge-surface 166 may have a substantially horizontal orientation, such that transmittal of vertical force from the upper load-carrying member 502 to the lower load-carrying member 503 in the upper switch state without incurring any longitudinal force component acting to displace the lower load-carrying member 503 in the longitudinal direction L is enabled. In other words, each of the upper and lower load-carrying members 502, 503 may have a first sliding surface segment including an inclined wedge-surface located next to a second sliding surface segment comprising a part having a substantially horizontal surface.
In the upper switch state, the second sliding surface segment comprising a part having a substantially horizontal surface of the upper and lower load-carrying members 502, 503 are in mutual contact and arranged to transmit vertical load. In the lower switch state, the first sliding surface segment including an inclined wedge-surface of the upper and lower load-carrying members 502, 503 are in mutual contact.
The upper and lower inclined wedge- surfaces 165, 166 may have cooperating tracks (not showed) for improving stability and reliability during their relative motion.
The cooperating tracks may for example be formed of a protrusion in one of the upper and lower inclined wedge- surfaces 165, 166 and a corresponding recess in the other of upper and lower inclined wedge- surfaces 165, 166. Thereby relative displacement in the transverse direction T is prevented.
For ensuring that each pair of cooperating upper and lower load-carrying members 502, 503 remain in contact with each other, each said pair comprises a locking device 194 that enable relative motion in the longitudinal direction L but prevents the cooperating upper and lower load-carrying members 502, 503 from becoming disengaged from each other.
An example embodiment of the locking device 194 is illustrated in FIGS. 17a and 17b . FIG. 18 schematically shows an example cross-section of a pair of cooperating upper and lower load-carrying members 502, 503 including the locking device 194 along line C-C in FIG. 17 a.
For example, the upper load-carrying member 502 may be provided with a lateral protrusion 195 arranged adjacent the downwards facing inclined wedge-surface 165 and protruding in the transverse direction T and extending in the longitudinal direction L along the length of the upper load-carrying member 502. This lateral protrusion 195 may be configured to interact with a locking hook 196 of the lower load-carrying member 503, which locking hook engages behind the lateral protrusion 195 to prevent the upper and lower load-carrying members 502, 503 from disengaging.
The lateral protrusion 195 may be a separate part welded or otherwise attached to the upper load-carrying member 502, or integrally formed in the upper load-carrying member 502. Similarly, the locking hook 196 may be a separate part welded or otherwise attached to the lower load-carrying member 503, or integrally formed in the lower load-carrying member 503.
FIG. 19 shows an example embodiment of a common power casing 185 comprising a power source 901 drivingly connected to the first and second driving members 186, 187. The power source is typically an electrical motor that is drivingly connected to an input shaft of a transmission 902. The transmission 902 further comprises first and second output shafts 903, 904 that are configured to rotate in opposite directions. The first and second output shafts 903, 904 may be oriented in the transverse direction T. Each output shaft 903, 904 is subsequently drivingly connected to one of the first and second driving members 186, 187 via a suitable gear mechanism 905, 906. The first and second driving members 186, 187 may be oriented in the longitudinal direction L. An advantage of providing the transmission 902 with a first and second output shafts 903, 904 that are configured to rotate in opposite directions is that the switch blades 141, 142 or switch frog rail segments 143, 144 are automatically controlled to be located in mutually exclusive positions, such that the risk for conflicting switching between the first and second switch blades 141, 142 or first and second switch frog rail segments 143, 144 is reduced. Alternatively, an individual power source may be provided for each driving member 186, 187.
FIGS. 20a and 20b show a schematic cross-section of still a further example embodiment of a railway switch mechanism in a cut similar to that of FIGS. 5a and 5b and having the second switch blade 142 in an upper and lower switch state, respectively. According to this example embodiment, each of the first and second displacement mechanisms 200 a, 200 b are located in four individual and separate casings 307 a, 307 b, 307 c, 307 d that are arranged substantially aligned in a substantially longitudinal direction L and interconnected by a moveable driving members 189.
An actuator 300, such as a hydraulic or pneumatic cylinder, operates as power source and controls longitudinal motion of the second displacement mechanism 200 b via a a second driving member 187. Forming each of the first and second displacement mechanisms 200 a, 200 b by four individual and functionally interconnected casings 307 a, 307 b, 307 c, 307 d offers the advantage of enabling replacement of only one casing in case of malfunction, thereby increasing the maintenance flexibility and reducing maintenance cost.
In this specific example embodiment, the second displacement mechanism 200 b is configured for providing a vertically translatory motion between the upper and lower switch state for enabling the vertical switch movement of the second switch blade 142, similar to that described with reference to FIGS. 7a and 7b . Hence, the second intermediate support member 214 a that is located between the second vertical displacement mechanism 201 a and the second switch blade 142 moves in a translatory motion between the upper and lower switch state, without any change in inclination thereof. As a result, all casings may have a similar or even identical design.
In other words, each casing may comprise a single, one-piece, second intermediate support member 214 a.
Each casing further comprises at least one motion control arrangement 501, and at least one pair of cooperating upper and lower load-carrying members 502, 503. In particular, in the specific example embodiment of FIG. 20a , each casing comprises two motion control arrangements 501 and four pairs of cooperating upper and lower load-carrying members 502, 503, and all casings 301 a-307 d may be identical.
Moreover, in this specific example embodiment of the railway switch mechanism 100 the second switch blade 142 is configured to be bent down elastically, i.e. to be elastically deformed to reach the lower switch state. This scenario is schematically described with reference to FIG. 20b , which shows the second switch blade 142 in the elastically deformed state, which here represents the lower switch state of the second switch blade 142.
Line 700 in FIG. 20b represents the position of the upper side of the second switch blade 142 in the upper switch state, as shown in FIG. 20a . The second switch blade 142 has thus been displaced vertically downwardly about 5-15 cm over a length L2 of about 40-75% of the total longitudinal length D1 of the second displacement mechanism 201 a.
The relatively long length L5 over which the second switch blade is elastically deformed to reach the vertical position of the lower switch state ensures acceptable stress levels in the material of the second switch blade 142, such that failure of the second switch blade 14 due to material fatigue is eliminated also after several million switch motions.
The individual casings 307 a-307 d may be designed to provide individual vertical displacement (not showed) according to the actual elastic deflection shape of the second switchblade 142 in FIG. 20b . This would require at least partly different types of casings along the length of the second switch displacement 201 a for conforming the bent shape of the second switch blade 142.
According to an alternative example embodiment, as described with reference to FIGS. 20a and 20b , each casing provides the same vertical displacement motion, thereby enabling use of more or less identical casings, possibly varying merely in terms of their longitudinal length and number of included motion control arrangements 501 and/or pairs of cooperating upper and lower load-carrying members 502, 503. Thereby, the total cost for the railway switch mechanism 100 can be reduced. However, due to the gradual vertical displacement of the second switch blade 142 in the longitudinal direction L over length L5, there exists a discrepancy between the vertical motion of the second switch blade 142 and the second displacement mechanism 201 a in the area close the heel 701 of the second switch blade 142, which discrepancy decreases along the longitudinal direction L over said length L5, as seen from the heel 704 of the second switch blade 142.
The heel 701 may be located at the transverse wall 164, 164 b of the support frame 160 a, 160 b.
One approach for handling this discrepancy in motion is to have a less strong attachment, or even no attachment, of the second switch blade 142 to the second displacement mechanism 201 a in the area close the heel 701 of the second switch blade 142 for allowing the second displacement mechanism 201 a in the area close the heel 701 to be vertically displaced to a higher degree than the second switch blade 142.
In other words, the second switch blade 142 may more or less be configured to float freely a length corresponding to the length L5, and to be permanently and non-movably fastened relative to an upper attachment surface of the second displacement mechanism 201 a over a longitudinal length L7. This arrangement enables the second switch blade 142 to deform elastically to the lower switch state with a minimum of stresses.
An installation according to this example embodiment is schematically illustrated in an exaggerated deflection view of the second switch blade 142 in FIG. 21, which corresponds to the design described with reference to FIGS. 20a and 20b . In FIG. 21, the elastic deformation of the second switch blade 142 and the free floating length L5 can be more easily recognised.
In the example embodiment illustrated in FIG. 21 the second switch blade is free from attachment arrangements to the second displacement mechanism 201 a over the length L5, and mounting bolts 702 for securing the second switch blade 142 to the second displacement mechanism 201 a is only available over the longitudinal length L7 of the second displacement mechanism 201 a.
In other words, the second switch blade 142 may be vertically non-movably secured relative to each of the third and fourth casings 307 c, 307 d at for example five locations spread in the longitudinal direction, and to the second casing 307 b at for example two locations spread in the longitudinal direction, by means of mounting bolts 702.
The longitudinal length L7 may for example correspond to 25-80%, specifically 40-75%, of a total length D1 of second displacement mechanism 201 a.
For providing a certain degree of lateral support to the first and second switch blades 141, 142 in the upper switch state they may be provided with some type of lateral support relative the first and second displacement mechanisms 200 a, 201 a.
For example, as schematically indicated in FIGS. 20a and 20b and contrary to the embodiment of FIG. 21, mounting bolts 702 may be provided for securing the second switch blade 142 to the second displacement mechanism 201 a, specifically to an upper side of the second intermediate support member 214 a of the casings 701 a-701 d. However, due to said discrepancy in vertical motion in the area of length L5 these mounting bolts 702 cannot permanently clamp the second switch blade 142 to the upper surface of second displacement mechanism 201 a.
According to one example embodiment, the mounting bolts 702 may be installed in an untightened state to a certain degree for enabling the second switch blade 142 to vertical slide along the shank of the mounting bolt 702, and thereby allow said discrepancy in vertical motion in the area of length L5.
Alternatively, the second switch blade 142 may be fastened to the second displacement mechanism 201 a by flexible rail fastening members (not showed) that allow relative vertical motion between the second switch blade 142 and the upper surface of the second displacement mechanism 201 a.
Still more alternatively, lateral support brackets may be welded or otherwise fastened to the upper surface of the second intermediate support member 214 a of each casing in the floating area, which lateral support brackets are configured for providing lateral support to the second switch blade 142 in the upper switch state. In the lower switch state, no lateral support is needed because the second switch blade 142 does not carry any load in the lower switch state.
In other words, each of the first and second vertical displacement mechanisms 200 a, 201 a, 200 b, 201 b may be provided with a first and second intermediate support member 213 a, 214 a, respectively, and configured for controlling the vertical displacement of said first and second intermediate support member 213 a, 214 a, respectively, between the upper and lower switch state, wherein each of the first and second switch blade 141, 142 or first and second switch frog rail segment 143, 144 is non-movably attached relative to an upper surface of the first and second intermediate support member 213 a, 214 a, respectively, over a longitudinal length L7 that corresponds to 25%-80%, specifically 40%-75%, of a total length D1 of the first and second vertical displacement mechanisms mechanism 200 a, 201 a, 200 b, 201 b, and wherein each of the first and second switch blade 141, 142 or first and second switch frog rail segment 143, 144 is vertically movably attached or unattached relative to an upper surface of the first and second intermediate support member 213 a, 214 a, respectively, over a longitudinal length L5 that corresponds to 20%-75%, specifically 25%-60%, of a total length D1 of the first and second vertical displacement mechanisms mechanism 200 a, 201 a, 200 b, 201 b.
Moreover, each of the first and second vertical displacement mechanisms 200 a, 201 a, 200 b, 201 b may be provided with a first and second intermediate support member 213 a, 214 a, respectively, and configured for controlling a vertical displacement of said first and second intermediate support member 213 a, 214 a, respectively, between the upper and lower switch state, wherein each of the first and second switch blade 141, 142 or first and second switch frog rail segment 143, 144 is attached to an upper surface of the first and second intermediate support member 213 a, 214 a, respectively, wherein each of the first and second switch blades 141, 142 or first and second switch frog rail segments 142, 144, for enabling the vertical switch movement, are elastically bendable in the vertical direction, or pivotally connected to the railway switch mechanism 100 by a hinged joint, and wherein each of the first and second intermediate support members 213 a, 214 a is translatory moveable between the upper and lower switch state.
The vertical elastic downwards deflection of the second switch blade 142 over the length L5 typically results in a significant lifting forces of the second closure rail 171 in a section adjacent the heel 701 of the second switch blade 142. Consequently, the railway switch mechanism 100 according to the example embodiment of FIGS. 20a, 20b and 21 comprises reduced fastening strength of the second closure rail 171 over a length L6 starting from the heel 701 of the second switch blade 142, i.e. at the lateral wall 164 a of the support frame. Thereby, the second closure rail 171 may lift a certain degree from the underlying support surface for ensuring a reduced stress level of the second closure rail 171 and second switch blade 142 in the vertically lower switch state.
For compensating the reduced stability caused by reduced fastening of the second closure rail 171 over the length L6 a slab track section 703 may be provided over the length L6, and after the slab track section 703, conventional sleepers 303 may be used. A slab track section generally provides a stronger and more stable support for the first and second closure rails 170, 171 than conventional sleepers 303, in particular when the second closure rail 171 is secured with reduced fastening strength.
FIG. 22 schematically shows a top view of an example embodiment of the railway switch mechanism 100 of the first and second switch blades 141, 142 similar to the embodiment of FIG. 2, but here in form of four casing railway switch mechanism. A slab track section 703 is shown being located side by side with the transverse side wall 164 a of the frame 160 a, similar as described with reference to FIGS. 20a and 20 b.
FIGS. 23a and 23b schematically show a cross-section of railway switch mechanism similar to that illustrated in FIGS. 3a and 3b , but here instead along cut D-D in FIG. 22, representing a railway switch mechanism in the two different switching state according to the example embodiment of FIGS. 20a and 20b , respectively.
In other words, the cross-section of FIG. 23a corresponds to a cut through the casing 307 a of FIG. 21a , with the second switch blade 142 and the second displacement mechanism 201 a in the upper switch state, and with the first switch blade 141 and the first displacement mechanism 200 a in the lower switch state. By analogy, the cross-section of FIG. 23b corresponds to a cut through the casing 307 a of FIG. 21b , with the second switch blade 142 and the second displacement mechanism 201 a in the lower switch state, and with the first switch blade 141 and the first displacement mechanism 200 a in the upper switch state.
The overall structure of the railway switch mechanism 100 in FIGS. 23a and 23b corresponds to that described with reference to FIGS. 3a and 3b and will not be repeated here. The difference is that the cross-section of FIGS. 23a and 23b shows an example embodiment of a floating first and second switch blades 141, 142.
In particular, in FIG. 23a , the first switch blade 141 is in the lower switch state, but due the aforementioned discrepancy in terms of vertical motion between the first intermediate support member 213 a of the first casing 307 a and the first switch blade 141 in the lower switch state, there is a vertical gap 705 between the first intermediate support member 213 a of the first casing 307 a and the first switch blade 141, and the first switch blade 141 has only been deflected a relatively small vertical distance 706 downwards. The first switch blade 141 is thus in a floating state.
Untightened attachment bolts 702 may be provided in the first and second intermediate support members 213 a, 214 a for providing lateral support to the switch blades 141, 142, while allowing relative vertical motion.
The second switch blade 142 is positioned on the second intermediate support member 214 a but without any strong fastening to the second intermediate support member 214 a for enabling switching to the lower switch state. Hence, also the second switch blade 142 is only provided with lateral support.
FIG. 23b shows the opposite switch state, i.e. with the second switch blade 142 in the lower switch state, but due the aforementioned discrepancy in terms of vertical motion between the second intermediate support member 214 a of the first casing 307 a and the second switch blade 142 in the lower switch state, there is a vertical gap 705 between the second intermediate support member 214 a of the first casing 307 a and the second switch blade 142. Consequently, the second switch blade 142 is in a floating state.
The floating arrangement of the first and second switch blades 141, 142 described with reference to FIGS. 20a, 20b , 21, 23 a and 23 b is not limited to a multi-casing switching mechanism, and may thus alternatively be implemented in a single casing switching mechanism, or a multi-casing switching mechanism with two, three, five or more casings aligned along a longitudinal direction.
FIG. 24 schematically shows a perspective view of an example of a slab track section 703. This may for example correspond essentially to a rigid section cast in concrete or similar material. Longitudinally extending channels 707 may be provided for housing the first and second closure rails 170, 171, as well as the first and second outer rails 111, 112. As schematically illustrated in FIGS. 25 and 26, the first and second closure rails 170, 171 may be provided with a relatively flexible fastening, or even be free floating relative to the slab track section for enabling the aforementioned lifting of the first and second closure rails 170, 171, respectively.
Hence, FIG. 25 schematically shows a cross-section the slab track section 703 along cut E-E in FIG. 22, and corresponding to the switch state of FIG. 23b , wherein the first switch blade 141 is in the upper switch state and the second switch blade 142 is in the lower switch state. As a result, the second closure rail 171 is slightly lifted from the support surface of the slab track section 703, while the first closure rail 170 remains in contact with the support surface of the slab track section 703.
By analogy, FIG. 26 schematically shows a cross-section the slab track section 703 along cut E-E in FIG. 22, and corresponding to the switch state of FIG. 23a , wherein the first switch blade 141 is in the lower switch state and the second switch blade 142 is in the upper switch state. As a result, the first closure rail 170 is slightly lifted from the support surface of the slab track section 703, while the second closure rail 171 remains in contact with the support surface of the slab track section 703.
The closure rail fastening structure 708 may enable a certain lifting of the first and second closure rails 170, 171 under tension of a spring member, or the like. Alternatively, the first and second closure rails 170, 171 may be entirely free from attachment in the vertical direction and only have lateral support. This type of less strong fastening of the first and second closure rails 170,171 may exist of the length of about 1-5 metres from the heel 701 of the first and second switch blades.
The first and second outer rails 111, 112 are not moving during the switching and remains permanently and non-movably secured relative to the slab track section 703.
Consequently, first and second closure rails 170, 171 of the railway switch mechanism 100 may be vertically movably attached or unattached relative to an upper surface of a support structure over a longitudinal length L6 in the range of 1-5 metres starting from the heel 701 of the first and second switch blade 141, 142 or first and second switch frog rail segment 143, 144.
Moreover, the railway switch mechanism 100 further comprises a slab track section 703 installed side by side with the support frame 160 a, 160 b for providing support to first and second closure rails 170, 171, and wherein the first and second closure rails 170, 171 of the railway switch mechanism 100 are vertically movably attached or unattached relative to an upper surface of the slab track section 703.
The switch mechanism has at least partly been mainly described as having both vertically displaceable switch blades 141, 142 and vertically displaceable switch frog rail segments 143, 144. However, the invention is applicable also when applied solely to the switch blades 141, 142 or solely to the switch frog rail elements 143, 144. A switch mechanism having vertically displaceable switch blades 141, 142 and a stationary frog may be preferred in certain applications, for example at locations where only low speed and/or infrequent driving occurs and the problems of reduced comfort and increased wear do not motivate the increased complexity of a switch frog compared with a stationary frog. In such installations, depending on the size, shape and form of the switch mechanism 100, the switch blades 141, 142 may extend more or less all the way to the switch frog 150, if deemed advantageous considering the specific circumstances.
The disclosure related to the second displacement mechanism 201 a and second switch blade 142 in FIGS. 5a -26 is equally applicable to the first displacement mechanism 200 a and first switch blade 141, as well as to the first and second displacement mechanism 200 b, 201 b associated with the switch frog 150 and including first and second switch frog rail segment 143, 144.
Moreover, even if each of the first and second displacement mechanisms 200 a, 200 b described with reference to FIG. 5a-17b have been disclosed primarily as being located in a single casing 307, the disclosure is not limited to such an implementation. On the contrary, each of the first and second displacement mechanisms 200 a, 200 b described with reference to FIG. 5a-17b may equally well be located in multi-casing arrangements, i.e. arrangements having two, three, four, or more, cooperating individual casings that are arranged substantially aligned in a longitudinal direction L.
In particular, in multi-casing embodiments wherein the vertical switch movement of the first and second switch blades 141, 142 is accomplished by elastic deformation (bending) of said first and second switch blades 141, 142 in the vertical direction V, or by pivoting motion of the first and second switch blades 141, 142 around one or two pivot joints, the various casing may have different designs for adapting the vertical movements of the casings to the form of the switch blades 141, 142 in the lower switching state. For example, the casing 307 a located closest to the heel end of the switch blades 141, 142, i.e. closer to the first and second closure rails 170, 171, may be designed according to any of the embodiments described with reference to 5 a, 5 b, 6 a, 6 b and 6 c, and the one or more casings 307 b located closer to the free end of the switch blades 141, 142, i.e. closer to the first and second closure rails 170, 171, may be designed according to any of the embodiments described with reference to 7 a, 7 b, 16 a, 16 b, 17 a, 17 b. Other casing combinations may be selected depending on the specific circumstances.
The term elastic deformation means deformation within a range that ends when the material reaches its yield strength. At this point plastic deformation begins. Elastic deformation is reversible, which means that an object will return to its original shape, but plastic deformation is irreversible.
The present invention has been disclosed and illustrated mainly in terms of standard right-hand diverging railway turnout but also other railway switch embodiments are included in the present invention, such as standard left-hand switches, single or double inside or outside slip switch, three way switch, stub switch, wye switch (Y points), or the like.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. It is appreciated that various features of the above-described examples can be mixed and matched to form a variety of other alternatives. As such, the described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be included within their scope.
Reference signs mentioned in the claims should not be seen as limiting the extent of the matter protected by the claims, and their sole function is to make claims easier to understand.

Claims

1. A railway switch mechanism comprising:

a first switch blade and/or first switch frog rail segment that is vertically displaceable by means of a first displacement mechanism in order to establish a vertical switch movement of the first switch blade and/or first switch frog rail segment between an upper and lower switch state; and

a second switch blade and/or second switch frog rail segment that is vertically displaceable by means of a second displacement mechanism in order to establish a vertical switch movement of the second switch blade and/or second switch frog rail segment between an upper and lower switch state, wherein each of the first and second displacement mechanisms comprises:

a motion control arrangement configured for providing vertical displacement of an associated switch blade or switch frog rail segment in response to horizontal displacement of at least one lower motion control member, and

at least one pair of cooperating upper and lower load-carrying members that are configured to be in contact with each other and transmit load from the associated switch blade or switch frog rail segment to the lower load-carrying member via the upper load-carrying member when the associated switch blade or switch frog rail segment is in the upper switch state.

2. The railway switch mechanism according to claim 1, wherein the at least one pair of cooperating upper and lower load-carrying members are configured to be not in contact with each other at least partly along a displacement path of the upper and lower load-carrying members from the upper switch state to the lower switch state.

3. The railway switch mechanism according to claim 1, wherein the motion control arrangement, for enabling a vertical switch movement of the first or second switch blade or first or second switch frog rail segment from the lower switch state to the upper switch state, is configured for:

providing upward vertical displacement of an associated switch blade or switch frog rail segment beyond the upper switch state, such that a downward-facing load-carrying surface of an upper load-carrying member is located vertically offset from a upward-facing load-carrying surface of a lower load-carrying member, and

subsequently providing downward vertical displacement of the associated switch blade or switch frog rail segment to the upper switch state, in which the downward-facing load-carrying surface of the upper load-carrying member contacts and enables load transmission from the associated switch blade or switch frog rail segment to the upward-facing load carrying surface of the lower load-carrying member.

4. The railway switch mechanism according to claim 1, wherein the railway switch mechanism further comprises a support frame in which each of the first and second displacement mechanisms are located, wherein the support frame has a bottom and at least two substantially longitudinal side walls carrying first and second outer rails and enclosing the first and second displacement mechanisms, and wherein each of the first and second displacement mechanisms is fastened to the support frame.

5. The railway switch mechanism according to claim 4, wherein the support frame is provided with an electrical heating mechanism located near each of the first and second stationary lateral support structures.

6. The railway switch mechanism according to claim 1, wherein the first and second displacement mechanisms are driven by a first and second driving members, respectively, and wherein the railway switch mechanism further comprises a single power source that simultaneously drives both the first and second driving members.

7. The railway switch mechanism according to claim 1, wherein the at least one pair of cooperating upper and lower load-carrying members comprises a locking arrangement for mutually interlocking the upper and lower load-carrying members in the upper switch state for preventing relative vertical motion, preferably relative vertical and transverse motion, between the upper and lower load-carrying members in the upper switch state.

8. The railway switch mechanism according to claim 1, wherein the motion control arrangement further comprises at least one upper motion control member, wherein the at least one lower motion control member and the at least one upper motion control member are configured to interact for translating a substantially horizontal displacement of the at least one lower motion control member to a substantially vertical displacement of the at least one upper motion control member, and wherein the at least one upper motion control member is directly or indirectly fastened to the first or second switch blade or first or second switch frog rail segment, such that the first and second switch blades or first or second switch frog rail segment can be selectively positioned in an upper and lower switch state by substantially horizontal displacement of the at least one lower motion control member.

9. The railway switch mechanism according to claim 1, wherein the at least one lower motion control member is configured to interact with the at least one upper motion control member via at least one inclined sliding surface or via at least one pivoting joint.

10. The railway switch mechanism according to claim 1, wherein one of the at least one lower motion control member and at least one upper motion control member comprises a guide track with an inclined path, and the other of the at least one lower motion control member and at least one upper motion control member comprises a guide member arranged to be guided by the guide track.

11. The railway switch mechanism according to claim 1, wherein the at least one lower motion control member is configured to be displaced in a direction substantially parallel to a longitudinal direction of the first or second switch blade or first or second switch frog rail segment.

12. The railway switch mechanism according to claim 1, wherein displacement of the at least one lower motion control member in a direction substantially parallel to a longitudinal direction of the first or second switch blade or first or second switch frog rail segment is configured to cause relative horizontal displacement between the load-carrying surfaces of the at least one lower load-carrying member and the at least one upper load carrying member, thereby enabling lowering of the associated switch blade or associated switch frog rail segment from the upper switch state to the lower switch state.

13. The railway switch mechanism according to claim 1, wherein the at least one lower load-carrying member is rigidly connected directly or indirectly to the at least one lower motion control member, such that they move uniformly.

14. A railway switch mechanism according to claim 1, wherein each of the first and second displacement mechanisms comprises at least one pair of cooperating upper and lower wedge-shaped load carrying members that are configured to transmit load from the associated switch blade or switch frog rail segment to the lower load-carrying member via the upper load-carrying member when the associated switch blade or switch frog rail segment is in the upper switch state, and configured for providing vertical displacement of an associated switch blade or switch frog rail segment in response to horizontal displacement of the lower wedge-shaped load-carrying member.

15. A method for operating a railway switch mechanism, the method comprising establishing a vertical switch movement of a first and second switch blade or first and second switch frog rail segment between an upper and lower switch state, the first switch blade or first switch frog rail segment is vertically displaceable by means of a first displacement mechanism in order to establish a vertical switch movement of the first switch blade or first switch frog rail segment between an upper and lower switch state; and the second switch blade or second switch frog rail segment that is vertically displaceable by means of a second displacement mechanism in order to establish a vertical switch movement of the second switch blade or second switch frog rail segment between an upper and lower switch state.