US2371064A - Railway switch operating apparatus - Google Patents
Railway switch operating apparatus Download PDFInfo
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- US2371064A US2371064A US507357A US50735743A US2371064A US 2371064 A US2371064 A US 2371064A US 507357 A US507357 A US 507357A US 50735743 A US50735743 A US 50735743A US 2371064 A US2371064 A US 2371064A
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- switch
- lever
- positions
- points
- spring
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L5/00—Local operating mechanisms for points or track-mounted scotch-blocks; Visible or audible signals; Local operating mechanisms for visible or audible signals
- B61L5/02—Mechanical devices for operating points or scotch-blocks, e.g. local manual control
Definitions
- My invention relates to railway switch operating apparatus, and particularly to apparatus of the typewhich includes a hand lever for throwin a spring switch.
- One object of my invention is the provision in apparatus of the type described of means for preventing the hand lever from being thrown to either extreme position unless the switch points move to the corresponding extreme position.
- Another object of my invention is to prevent the possibility of the hand lever from being jerked out of an operators hands if he attempts to reverse the switch when the spring which biases the points to their set positions is compressed beyond its normal compression due for example to the presence of an obstruction which prevents the switch points from assuming theextrerne position corresponding to the position of the hand lever.
- I attach two bars to the normally closed point in parallel spaced relation. These bars extend underneath the one stock rail adjacent to the switch operating mechanism and are provided at their free ends with upstanding arms which are threaded to receive adjustable'bolts.
- the parts are so adjusted and so proportioned that the hand throw lever of the switch operating mechanism can only be moved to or away from its normal position past the one bolt when the switch points occupy their full normal positions, and that the hand throw lever'can only be moved to or away from its reverse position past the other bolt when the switch points occupy their full reverse positions.
- Fig. 1 is a'top plan view partly cross sectioned showing a spring switch provided with one form of switch operating apparatus embodying my invention.
- Fig. 2 is an end View of the apparatus shown in Fig. 1.
- Fig. 3 is a sectional view taken on the lines IIIIII of Fig. 1.
- Fig. 4 is a detail View showing in isometric projection on an enlarged scale a portion of the apparatus shown in 'Figs. 1 and 2.
- the reference character A designates a railway switch comprising as-usual'two fixed rails l and la and. two movable rails or switch points 2 and 2a.
- the movable 55 rails are fastenedtogether by a front rodi5 and a head rod 6, and maybe moved into a normal or a reverse position by mean of a switch operating mechanism B which is connected with the head rod 6 through the medium of a link-9 and a spring connecting rod 0.
- a switch operating mechanism B which is connected with the head rod 6 through the medium of a link-9 and a spring connecting rod 0.
- the switch operating mechanism B may be of any suitable type, but as here shown,..it comprises a switch stand 10 having its base Illa spiked or otherwise secured to the ties adjacent to the switch A.
- a gear shaft III is journaled in the switch stand I!) and carries a crank Ila and a gear segment I2.
- the crank Ha of the switch stand B is pivotally connected to one end of the link 9, while the gear segment I2 meshes with a pinion gear l3 keyed to a pinion shaft 2:0.
- The, pinion shaft 20 extends through the side of the switch stand I 0, and has attached to its outer end the usual weighted switch throwing lever 2i.
- the spring connecting rodC may have any suitable form, but in the wellknown form here shown, this connecting rod comprises a cylindricalv housing l'4 having a lateral extension Ma fastened to the head rod 6.
- the left-hand end Mb of the housing M has a smaller diameter than the body of the housing, while the right-hand end is threaded to receive a cap I5 having an end l5a similar to the end Mb.
- a sleeve l6 mounted in the opening in the end 1419. is a sleeve l6 provided with an annular flange l6a located within the and I?
- this rod carries a compression spring l9 which engages the sleeves at the annular flanges, and urges the sleeves toward the positions in which Jthe annularflange Ilia of the sleeve 16 engages the shoulder formed on the inner'side of thehousing M by the endl-4b, and the annular flange of the sleeve l1 engages the shoulder formed on the inside of the cap l5 by the end Ho.
- the spring rod I8 is provided with an annular shoulder 18a for at times engaging the outer end of the :sleeve H, and with a nut Iflb for at times engaging the outer end of the sleeve 16.
- the spring-rod I8- is alsoprovided with a nut
- the right-hand end of the spring rod i3 is pivotally attached to the link H.
- both the switch A and the switch operating mechanism B occupy their normal positions, and the parts are so proportioned that under these conditions a, force will be transmitted to the switch points 2 and 2a through the medium of the link Spring rod I8, nut l8b, sleeve Spring l9, sleeve housing M and head rod 6, which force will cause the spring l9 to become compressed and yieldably urge the.
- When the switch points occupy their normal positions as shown and it is desired to reverse them, the switch throwing lever 2
- the motion of the spring rod it toward the left causes a force to be exerted on the switch points 2 and 2a through the medium of the shoulder 18a, sleeve spring
- this apparatus comprises two bars 25 and 3
- These bars are slidably supported intermediate their ends by suitable guides 4
- a or 32a which is normally held in a fixed position realtive to the associated bolt by means of a pin 33.
- This pin passes through clearance holes in the bolt and tubular extension and is drilled at its lower end for the reception of a wire seal 34 which must be broken in order to enable the tubular extension to be removed, for a purpose which will appear presently, and which when removed'leaves a telltale of its removal for a purpose which will also appear presently.
- the parts are so proportioned and bolts 3
- Such abnormal operation of the lever might be necessary, for example, if a train which has stopped for some reason while trailing the switch desires to back up to take up slack reparatory to making a new start.
- the fact that the trainman has to break the wire seal in order to operate the lever under the conditions just described provides a telltale of the abnormal operation of the lever, and insures that the trainman will report such operation.
- functions in a similar manner to prevent a trainman from. operating the switch points to their normal positions when they are displaced from their reverse positions without first taking proper precautions to avoid possible injury from rapid acceleration of the lever caused by the extra compression of spring 19, this rapid acceleration of the lever generally being refered to in the art as a flying lever.
- a railway switch an operating mechanism provided with a manually operable lever movable between two extreme positions, spring means connecting said mechanism with said switch in such manner that the switch will be biased to an extreme position corresponding to the extreme position of said lever, two rods secured to said switch for movement therewith on opposite sides of the vertical plane passing through the pivotal axis of said manually operable lever and each provided at its free end with an upstanding portion having a screw threaded hole, two bolts one adjustably screwed into each of said holes and with said lever, the parts being so proportioned and adjusted that the one bolt will project into the path of movement of said lever toward or away from its one extreme position except when the switch points are in their corresponding extreme positions and that the other bolt will project into the path of movement of said lever toward or away from its other extreme position except when the switch points are in their corresponding extreme positions.
- a railway switch an oper- I ating mechanism providedwith a manually operable lever movable between two extreme positions, spring means connecting said mechanism with said switch in such-manner that the switch will be biased to an extreme position corresponding to the extreme position .of said lever, two rods secured to said switch for movement therewith on opposite sides of the vertical plane passing through the pivotal axis of said manually operable lever and each provided at its free end with each cooperating an upstanding portion-having a.
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- Mechanisms For Operating Contacts (AREA)
Description
March 6, 1945. NYBERG I 2,371,)64
RAILWAY SWITCH OPERATING APPARATUS Filed Oct. 25, 1945 INVENTOR f/[J' ATTORNEY Patented Mar. 6, 1945 2,371,064 RAILWAY SWITCH-OPERATING APPARATUS Morgan A. Nyberg, Milwaukee, Wis., assignor to The Union Switch and Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application October 23, 1943, Serial No. 507,357
7 Claims.
My invention relates to railway switch operating apparatus, and particularly to apparatus of the typewhich includes a hand lever for throwin a spring switch. v
One object of my invention is the provision in apparatus of the type described of means for preventing the hand lever from being thrown to either extreme position unless the switch points move to the corresponding extreme position.
Another object of my invention is to prevent the possibility of the hand lever from being jerked out of an operators hands if he attempts to reverse the switch when the spring which biases the points to their set positions is compressed beyond its normal compression due for example to the presence of an obstruction which prevents the switch points from assuming theextrerne position corresponding to the position of the hand lever.
According to my invention, I attach two bars to the normally closed point in parallel spaced relation. These bars extend underneath the one stock rail adjacent to the switch operating mechanism and are provided at their free ends with upstanding arms which are threaded to receive adjustable'bolts. The parts are so adjusted and so proportioned that the hand throw lever of the switch operating mechanism can only be moved to or away from its normal position past the one bolt when the switch points occupy their full normal positions, and that the hand throw lever'can only be moved to or away from its reverse position past the other bolt when the switch points occupy their full reverse positions.
Other objects and characteristic features of my invention will become apparent as the description proceeds.
I shall describe one formof apparatus embody- I ing my invention, and shall then point out the novel features thereof in claims.
In the accompanying drawing, Fig. 1 is a'top plan view partly cross sectioned showing a spring switch provided with one form of switch operating apparatus embodying my invention. Fig. 2 is an end View of the apparatus shown in Fig. 1. Fig. 3 is a sectional view taken on the lines IIIIII of Fig. 1. Fig. 4 is a detail View showing in isometric projection on an enlarged scale a portion of the apparatus shown in 'Figs. 1 and 2.
Similar reference characters refer to similar parts in each of the several views.
Referring to the drawings, the reference character A designates a railway switch comprising as-usual'two fixed rails l and la and. two movable rails or switch points 2 and 2a.
The movable 55 rails are fastenedtogether by a front rodi5 and a head rod 6, and maybe moved into a normal or a reverse position by mean of a switch operating mechanism B which is connected with the head rod 6 through the medium of a link-9 and a spring connecting rod 0., When the switch occupies its normal position in which it is shown in Fig. 1, the movable rail 2a engages the fixed rail in and the movable rail 2 is spaced a slight distance from the fixed rail I. When the switch is reversed, however, the movable'rail '2 thenengages the fixed rail I and the movable rail 2c is spaced from the fixed rail la.
The switch operating mechanism B may be of any suitable type, but as here shown,..it comprises a switch stand 10 having its base Illa spiked or otherwise secured to the ties adjacent to the switch A. A gear shaft III is journaled in the switch stand I!) and carries a crank Ila and a gear segment I2. The crank Ha of the switch stand B is pivotally connected to one end of the link 9, while the gear segment I2 meshes with a pinion gear l3 keyed to a pinion shaft 2:0. The, pinion shaft 20 extends through the side of the switch stand I 0, and has attached to its outer end the usual weighted switch throwing lever 2i.
The spring connecting rodC may have any suitable form, but in the wellknown form here shown, this connecting rod comprises a cylindricalv housing l'4 having a lateral extension Ma fastened to the head rod 6.. The left-hand end Mb of the housing M has a smaller diameter than the body of the housing, while the right-hand end is threaded to receive a cap I5 having an end l5a similar to the end Mb. .Slidably mounted in the opening in the end 1419. is a sleeve l6 provided with an annular flange l6a located within the and I? with sufficient clearance to permit the rod to slide freely in the sleeves and this rod carries a compression spring l9 which engages the sleeves at the annular flanges, and urges the sleeves toward the positions in which Jthe annularflange Ilia of the sleeve 16 engages the shoulder formed on the inner'side of thehousing M by the endl-4b, and the annular flange of the sleeve l1 engages the shoulder formed on the inside of the cap l5 by the end Ho. The spring rod I8 is provided with an annular shoulder 18a for at times engaging the outer end of the :sleeve H, and with a nut Iflb for at times engaging the outer end of the sleeve 16. The spring-rod I8-is alsoprovided with a nut |8c for locking the nut |8b in an adjusted position. The right-hand end of the spring rod i3 is pivotally attached to the link H.
The portion of the apparatus thus far described is well known, and its operation is as follows: As shown in the drawing, both the switch A and the switch operating mechanism B occupy their normal positions, and the parts are so proportioned that under these conditions a, force will be transmitted to the switch points 2 and 2a through the medium of the link Spring rod I8, nut l8b, sleeve Spring l9, sleeve housing M and head rod 6, which force will cause the spring l9 to become compressed and yieldably urge the.
switch points to their normal positions.
When the switch points occupy their normal positions as shown and it is desired to reverse them, the switch throwing lever 2| is rotated from the position shown through an angle of 180 in a counterclockwise direction, thereby rotating gear segment l2 and crank I la in the same direction and hence moving link 9 and spring rod i8 toward the left. The motion of the spring rod it toward the left causes a force to be exerted on the switch points 2 and 2a through the medium of the shoulder 18a, sleeve spring |9, sleeve I6, housing l4, and head rod 6 which force moves the points to their reverse positions.
The parts are so proportioned that when the switch points reach their full reverse positions the spring 20 will become compressed beyond its initial compression and-will then exert a force on the points which yieldably holds them in their reverse positions.
If, after the switch points have been moved to their reverse positions in the manner just described, it is desired to restore them to their normal positions, this may be done by restoring the lever 2| to the position shown. The subsequent movements of the parts under these conditions is just the reverse of that described above, and will be apparent from the drawing without further description.
When the parts occupy the positions shown and a train trails the switch the wheels of the train exert a force on the closed switch point 2a which force causes the points to move over laterally in opposition to the bias of the spring l8, and as soon as the train clears the switch, the spring l9 acts to return the points to the positions shown in the drawing.
With the apparatus constructed in the manner 7 thus far described it is possible fora trainman to force the'switch throwing lever 2| to its full normal or full reverse position even thoughthe switch points are prevented from moving to the corresponding extreme position due to some obstruction such for example, as a lump of coal, snow and ice, or the like, and derailments have been reported due to a train moving over a spring switch on a hand signal under such a condition.
Moreover, with the switch A arranged to be operated in the manner described it sometimes happens that a train which has started to trail the switch stops for one reason or another in a position inwhich the switch points are held in their trailed positions by the wheels of one of the vehicles of the train, and that while the points are then held in their trailed positions, a trainman attempts to reverse the switch by means of the switch throwing lever 2|. When this happens, the operation of the mechanism releases the energy stored in the compressed spring of the spring connecting rod C, and causes this energy to be transmitted back through the spring rod l8, link 9, gear segment l2, bevel gear l3 and shaft 20 to the lever 2|, with the result that there is a tendency to jerk the lever 2| out of the trainmans hand. i
It is desirable to prevent this and the other condition described above from happening to guard against possible injury to the trainman, or derailment of the train, as the case may be, and to this end, I provide the apparatus forming the subject matter of my present invention, which apparatus I shall now describe.
As here shown, this apparatus comprises two bars 25 and 3|] which extend underneath the fixed rail |a in parallel spaced relation and are secured at oneend to the normally closed switch point 2a. These bars are slidably supported intermediate their ends by suitable guides 4| here shown assecured to the nearest tie, and are pro vided at their free ends with upstanding arms 25a and 30a, respectively, which arms are screw threaded to receive adjustable bolts 3| and 32, respectively. Mounted on the free end of each bolt is a removable tubular extension 3|a or 32a which is normally held in a fixed position realtive to the associated bolt by means of a pin 33. This pin passes through clearance holes in the bolt and tubular extension and is drilled at its lower end for the reception of a wire seal 34 which must be broken in order to enable the tubular extension to be removed, for a purpose which will appear presently, and which when removed'leaves a telltale of its removal for a purpose which will also appear presently.
The parts are so proportioned and bolts 3| and 32 are so adjusted that the tubular extension 32a on the bolt 32 will project into the path of movement of the lever 2| to or away from its normal position except when the switch points are in their fullnormal positions, and that the tubular extension Sla on the bolt 3| will project into the path of movement of the lever 2| to or awayv from case, for example, if a lump of coal or some other obstruction became lodged between the stock rail la and the switch point 2a, the tubular extension 3la on the bolt 3| will project into the path of movement of the lever 2| and will thus prevent it from being moved to its full reverse position. When this happens, the trainman will be made aware of the presence of the obstruction and will remove it, or will at least return the lever to its normal position, thereby avoiding any possibility of a derailment due to a, train moving over the switch with the switch points displaced from their full reverse posi tions, 1
Similarly, when the switch throwing lever 2| is operated from its reverse position toward its normal position to move the switch points to their normal position, the tubular extension 32a on the bolt 32 will prevent the lever 2| from being moved to its full normal position unless the switch points move to their full normal positions in response to the movement of the lever. 'If the switch points are displaced from their normal ositions for any reason when the lever 2| occupies its normal position, the tubular extension 32a will then overlie the lever, and will thus prevent the operator from moving thelever away from its normal position without first removing the extension 32a; done by removing the wire seal 34 and associated pin 33- and then slipping the extensi n 32a off the bolt 32, and it is assumed that if the trainman does this he will then take proper precautions when he moves the lever away from its normal position to prevent the lever from accelerating rapidly due to the abnormally high spring force which then exists in the spring I9 as a result of the displacement of the points from their normal positions. Such abnormal operation of the lever might be necessary, for example, if a train which has stopped for some reason while trailing the switch desires to back up to take up slack reparatory to making a new start. The fact that the trainman has to break the wire seal in order to operate the lever under the conditions just described provides a telltale of the abnormal operation of the lever, and insures that the trainman will report such operation.
The tubular extension am on the bolt 3| functions in a similar manner to prevent a trainman from. operating the switch points to their normal positions when they are displaced from their reverse positions without first taking proper precautions to avoid possible injury from rapid acceleration of the lever caused by the extra compression of spring 19, this rapid acceleration of the lever generally being refered to in the art as a flying lever.
Some advantages of apparatus embodying my invention are that it is simple in construction, A
relatively inexpensive to manufacture, and can be readily added to almost any type-of spring switch layout without necessitating any changes in the apparatus.
Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that'various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.
Having thus described my invention, what I claim is:
1. The combination with a switch and a, manually operable lever movable between two extreme positions and operatively connected with said switch through resilient means for moving said switch between its two extreme positions, of means secured to one of the movable points of said switch and cooperating with said lever to prevent movement of said lever to or away from its one extreme position unless the switch points occupy positions in agreement with the osition of said lever. v
2. The combination with a switch and a manually operable lever movable between two extreme positions and operatively connected with said switch through resilient means for moving said switch between its two extreme positions, of means secured to one of the movable points of said switch and cooperating with said lever to prevent movement of said lever to or away from either extreme position unless the switch points occupy positions in agreement with the position of said lever.
3. The combination with a switch and a manually operable lever rotatable between two extreme positions and operatively onnected with said switch through resilient means for moving said switch between corresponding extreme positions, of a member secured to one of the switch This can only be '3 points and provided with means which projects into the path of movement of said lever to or away from one of its extreme positions except when said switch occupies its corresponding extreme position.
4. The combination with a switch and a manually operable lever rotatable between two extreme positions and operatively c'onnectedwith said switch through resilient means for moving said switch between corresponding extreme positions, of two members secured to the switch points in parallel spaced relation to move therewith, means secured to the one member in such position that it will project into the pathof movement of said lever to or away from its one extreme position except when said switch occupies its corresponding extreme position, and other means secured to the other member in such position that it will ,project into the path of movement of said lever to or away from its other extreme position except when said switch occupies its corresponding extreme position.
5. The combination with a switch and a manually operable lever rotatable between two extreme positions and operatively connected with said switch through resilient means for moving said switch between corresponding extreme positions, of two members secured to the switch points in parallel spaced relation to move therewith, means removably secured to the one member in such position that it will project into the path of movement of said lever to oraway from its one extreme position except when said switch occupies its corresponding extreme position, and other means removably secured to the other member in such position that it will project into the path of movement of said lever to or away from its other extreme position except when said switch occupies its corresponding extreme position.
- 6. In combination, a railway switch, an operating mechanism provided with a manually operable lever movable between two extreme positions, spring means connecting said mechanism with said switch in such manner that the switch will be biased to an extreme position corresponding to the extreme position of said lever, two rods secured to said switch for movement therewith on opposite sides of the vertical plane passing through the pivotal axis of said manually operable lever and each provided at its free end with an upstanding portion having a screw threaded hole, two bolts one adjustably screwed into each of said holes and with said lever, the parts being so proportioned and adjusted that the one bolt will project into the path of movement of said lever toward or away from its one extreme position except when the switch points are in their corresponding extreme positions and that the other bolt will project into the path of movement of said lever toward or away from its other extreme position except when the switch points are in their corresponding extreme positions.
7. In combination, a railway switch, an oper- I ating mechanism providedwith a manually operable lever movable between two extreme positions, spring means connecting said mechanism with said switch in such-manner that the switch will be biased to an extreme position corresponding to the extreme position .of said lever, two rods secured to said switch for movement therewith on opposite sides of the vertical plane passing through the pivotal axis of said manually operable lever and each provided at its free end with each cooperating an upstanding portion-having a. screw threaded hole, two bolts one adjustably screwed into each of said holes, and two tubular extensions one removably secured to each bolt, the parts being so proportioned and adjusted that the one extension will project into the path of movement of said lever toward or away from its one extreme position except when the switch points occupy the corresponding extreme positions and that the other extension will project into the path of movement of said lever toward or away from its other extreme position except when the switch points occupy their corresponding extreme positions.
MORGAN A. NYBERG.
Priority Applications (1)
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US507357A US2371064A (en) | 1943-10-23 | 1943-10-23 | Railway switch operating apparatus |
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US507357A US2371064A (en) | 1943-10-23 | 1943-10-23 | Railway switch operating apparatus |
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US2371064A true US2371064A (en) | 1945-03-06 |
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US507357A Expired - Lifetime US2371064A (en) | 1943-10-23 | 1943-10-23 | Railway switch operating apparatus |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040112589A1 (en) * | 2000-10-02 | 2004-06-17 | Cook Robert Lance | Mono-diameter wellbore casing |
US20080018099A1 (en) * | 2003-02-18 | 2008-01-24 | Enventure Global Technology | Protective compression and tension sleeves for threaded connections for radially expandable tubular members |
-
1943
- 1943-10-23 US US507357A patent/US2371064A/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040112589A1 (en) * | 2000-10-02 | 2004-06-17 | Cook Robert Lance | Mono-diameter wellbore casing |
US20080018099A1 (en) * | 2003-02-18 | 2008-01-24 | Enventure Global Technology | Protective compression and tension sleeves for threaded connections for radially expandable tubular members |
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