GB2558525A

GB2558525A - Hinge assembly

Info

Publication number: GB2558525A
Application number: GB1611716.0A
Authority: GB
Inventors: William Edmonds Tracy
Original assignee: Era Home Security Ltd
Current assignee: Era Home Security Ltd
Priority date: 2016-07-05
Filing date: 2016-07-05
Publication date: 2018-07-18
Anticipated expiration: 2036-07-05
Also published as: GB201611716D0; CN207714960U; GB2558525B

Abstract

A hinge assembly (101 fig 2) for a window, the window comprises a window leaf and a corresponding window frame. The hinge assembly (101 fig 2) has a plurality of support arms (106, 108, 110 figure 2) each pivotally connected to one or more other of the support arms, to a sash plate 102 and or to a frame plate 104 to form a friction stay. The pivotal connections (116, 118, 120, 122, 124, 126 figure 2) provide a plurality of fixed pitches between connections. There is a pitch variation device 128 configured to allow variation of one or more of the fixed pitches 126 during opening and closing of the hinge assembly (101 figure 2). By varying the pitch of one of the connections, the geometry of the hinge assembly (101 figure 2) is adjusted, thus reducing the chance of misalignment and damage to the assembly.

Description

(54) Title of the Invention: Hinge assembly

Abstract Title: Friction stay hinge Assembly (57) A hinge assembly (101 fig 2) for a window, the window comprises a window leaf and a corresponding window frame. The hinge assembly (101 fig 2) has a plurality of support arms (106, 108, 110 figure 2) each pivotally connected to one or more other of the support arms, to a sash plate 102 and or to a frame plate 104 to form a friction stay. The pivotal connections (116, 118, 120, 122, 124, 126 figure 2) provide a plurality of fixed pitches between connections. There is a pitch variation device 128 configured to allow variation of one or more of the fixed pitches 126 during opening and closing of the hinge assembly (101 figure 2). By varying the pitch of one of the connections, the geometry of the hinge assembly (101 figure 2) is adjusted, thus reducing the chance of misalignment and damage to the assembly.

FIG. 4

1/3

FIG. 1

2/3

102

124

116

112

134

FIG. 3

3/3

FIG. 4

Hinge Assembly

Technical Field

The invention relates to friction stay hinge assemblies for windows and doors. Specifically, the invention relates to, but need not be limited to, four bar friction stay hinge assemblies and/or six bar friction stay hinge assemblies for windows.

Background

Windows typically comprise one or more movable window leafs and a window frame fitted into an opening in a wall. A variety of different hinges for windows are known depending on, among other things, the size and strength required. One such hinge is known as a friction stay and may be, for example, a four bar friction stay hinge, also known as a four bar stay. In a friction stay, the window is supported on a sash plate, which is connected by a plurality of support arms to a frame plate fitted to the window frame. In a four bar hinge, the sash plate and frame plate are connected by three support arms which pivot at their connections. One of the support arms is slidably connected to the frame plate to permit opening and closing of the window.

Therefore, in order for a friction stay hinge assembly to operate correctly and/or without placing undue stress on the components of the hinge assembly, each component of a friction stay hinge assembly must be specifically and precisely manufactured in relation to the other components in order for the friction stay to operate correctly. This is time consuming and costly.

Further, in known friction stays, movement of the elements of the stay may be such that a pointed end of the sash plate snags or makes contact with an end cap on a frame plate. This effect may occur and/or be exacerbated over time based on wear and tear of component parts or due to some other event that misaligns the friction stay. It is desirable to have a friction stay in which the pointed end moves clear of the end cap before moving outwards from the frame.

Summary

In order for windows to open and close reliably and consistently, it is important for a geometry of the hinge assemblies to be precise and accurate. A geometry of a friction stay hinge assembly is considered to be fixed when the fixed pitches between connection points of the hinge assembly remain the same. Two geometries of friction stay hinge assemblies are considered to be different if at least one fixed pitch between connection points of the two hinge assemblies is different.

As used herein, the term “fixed pitch” between connections of a friction stay encompasses the distance between connection points that, in known friction stay hinge assemblies, remain the same during the opening and closing operation. In the context of the invention, the term “fixed pitch” may be used as nomenclature only, as in aspects of the invention one or more “fixed pitches” may actually be variable. The fixed pitches may be measured along a length of one of the support arms, the frame plate or the sash plate.

The geometry of a friction stay hinge assembly may therefore be defined by the fixed pitches of the friction stay hinge assembly. The geometry of a friction stay hinge assembly need not be limited to the relative angles between the frame plate, sash plate and/or support arms at any given point during opening/closing of the hinge assembly, as those will be different dependent on the position of the hinge assembly. Rather, the geometry of a hinge assembly may be determined by the fixed pitches and the lengths of the frame plate, sash plate and/or support arms, as they define the travel of the sash plate during opening and closing of the hinge assembly.

The inventors have appreciated that by altering the length one or more support arms (or links) of a friction stay, the travel of those support arms during opening and closing of the window may be altered. Specifically, if a hinge support arm of a friction stay is increased in length the travel of the pointed end of the sash plate is altered such that it has greater clearance of the end cap of the frame plate before moving outwards from the frame. However, by altering a length of one or more support arms, such as by increasing the length of the hinge support arm, the geometry of a friction stay assembly is altered such that the friction stay hinge assembly is inoperable. This is because one of the fixed pitches of the friction stay hinge assembly has been altered and the remaining elements of the friction stay hinge assembly cannot accommodate the new geometry.

According to the invention in an aspect, there is provided a friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising: a plurality of support arms each pivotally connected to one or more other of the support arms, to a sash plate and/or to a frame plate to form a friction stay, wherein the pivotal connections provide a plurality of fixed pitches between connections; and characterised by a pitch variation device configured to allow variation of one or more of the fixed pitches during opening and closing of the hinge assembly.

It is noted again that the term “fixed pitches” is used in aspects of the invention to identify pitches that would normally be fixed if the geometry of the friction stay hinge assembly were fixed. As such, a “fixed pitch” may be purely nomenclature and may actually be variable in aspects of the invention.

Optionally, a plurality of support arms are pivotally connected to the frame plate, and wherein the pitch variation device forms part of a first pivotal connection to the frame plate and is configured to allow the first pivotal connection to move between first and second positions on the frame plate.

Optionally, at least one other of the pivotal connections of the plurality of support arms to the frame plate is slidable along the frame plate during normal opening and closing the window leaf.

Optionally, the pitch variation device is configured to permit movement of the first pivotal connection during an opening and/or a closing operation of the hinge assembly.

Optionally, the pitch variation device comprises a carriage moveable between the first and second positions.

Optionally, the hinge assembly further comprises a biasing means for biasing the pitch variation device into the second position.

Optionally, the pitch variation device forms part of a bridging support arm pivotal connection to the frame plate, and is configured to allow independent movement of the bridging support arm pivotal connection and a hinge support arm pivotal connection to the frame plate.

Optionally, the pitch variation device is in the first position the bridging support arm pivotal connection is further away from the hinge support arm pivotal connection, as compared to when the pitch variation device is in the second position.

Optionally, a main support arm is pivotally connected to the frame plate and is slidable along the frame plate during normal opening and closing the window leaf.

Optionally, the bridging support arm is also pivotally connected to the main support arm.

Optionally, the hinge support arm is in a range from 10% to 30% longer than a hinge support arm for a hinge assembly having a fixed geometry.

Optionally, the hinge support arm and the main support arm comprise pivotal connections to a sash plate.

Optionally, the hinge assembly is one of a four bar friction stay or a six bar friction stay.

According to the invention in a further aspect, there is provided a friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising: a sash plate for fitting to the window leaf; a frame plate for fitting to the window frame; a main support arm pivotally connected to the sash plate and the frame plate, the pivotal connection of the main support arm to the frame plate being slidable along the frame plate for opening and closing the window leaf; a hinge support arm pivotally connected to the sash plate and the frame plate; a bridging support arm pivotally connected to the main support arm and the frame plate; and a pitch variation device for varying a pitch between the pivotal connection of the bridging support arm to the frame plate and the pivotal connection of the hinge support arm to the frame plate.

Optionally, the pitch variation device is configured to permit the pivotal connection of the bridging support arm to be slidable along the frame plate. Optionally, the pivotal connection of the hinge support arm to the frame plate is in a fixed position on the frame plate.

Optionally, the pitch variation device may comprise any features discussed above in relation to other aspects of the invention.

According to the invention in a further aspect, there is provided a friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising: a frame plate for fitting to the window frame; and a plurality of support arms forming a friction stay, wherein at least three of the support arms are pivotally connected to the frame plate, and wherein at least two of the at least three pivotal connections are slidable along the frame plate on opening and/or closing of the friction stay hinge assembly. The at least two of the at least three pivotal connections may be independently slidable, that is, they may slide in different directions and/or at different rates on opening and/or closing of the window leaf. The support arms may comprise a main support arm, a bridging support arm and a hinge support arm, as described herein. The friction stay hinge assembly may further comprise a sash plate for fixing to the window leaf and to which the main support arm and the hinge support arm are pivotally connected.

The at least two of the at least three pivotal connections may optionally be the pivotal connection of the main support arm and the pivotal connection of the bridging support arm.

According to a further aspect of the invention, there is provided a friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising: a frame plate for fitting to the window frame; a sash plate for fitting to the window leaf; and a plurality of support arms connected at pivotal connection points to the frame plate, the sash plate and/or another of the support arms to form a friction stay, wherein the frame plate, sash plate and support arms are configurable in first and second geometries.

The friction stay hinge assembly may optionally comprise a pitch variation device configured to alter a pitch between two of the connection points for placing the friction stay hinge assembly in the first and second geometries. The pitch variation device may comprise any of the features of pitch variation devices disclosed herein.

According to a further aspect of the invention, there is provided a window assembly comprising a window leaf, a window frame and a hinge assembly according to any preceding claim.

By incorporating a pitch variation device into a friction stay hinge assembly, the geometry of the friction stay can be altered to accommodate differently sized support arms. This may allow an increase in the length of the hinge support arm without affecting the operation of the window, thereby allowing the pointed end of the sash plate to move clear of the end cap.

The pitch variation device allows variation of a normally fixed pitch between two connections of a friction stay that would normally be fixed connections. The pitch variation device moves between a first position, providing a first pitch between the connections, and a second position, providing a second pitch between the connections.

As used herein, “closed” in respect of a door or window is intended to mean when the hinge assembly is fully closed and cannot close any further; “open” is therefore any position which is not the “closed” position. There are, of course, multiple open positions for a hinge assembly depending on how far the friction stay has been opened.

The pitch variation device may be moved from the first position to the second position during an opening operation of the hinge assembly. This movement may be under a biasing force. The movement between the first and second position of the pitch variation device may be caused by the initial movement of the hinge assembly from a closed position to an open position. Alternatively, the movement between the first and second geometry may occur during a later stage of an opening operation of the hinge assembly.

Brief Description of the Figures

Exemplary embodiments of the invention will be described herein and with reference to the accompanying figures in which:

Figure 1 is a plan view of a four-bar friction stay hinge assembly;

Figure 2 is a perspective view of a part of a friction stay hinge assembly Figure 3 is a section through the part of the friction stay hinge assembly of Figure 2 along the line B-B; and

Figure 4 is a perspective section view of the part of the friction stay hinge assembly of Figure 2 along the line B-B.

Specific Description

Figure 1 shows a four-bar hinge assembly 1. The assembly 1 comprises a sash plate (or fourth link) 2, a frame plate (or track) 4, and three supporting arms: a hinge support arm (or first link) 6, a main support arm (or third link) 8, and a bridging support arm (or second link) 10 extending between the main support arm 8 and the frame plate 4. The sash plate 2 has a pointed end 12 which is configured to be received in an end cap 14 of the frame plate 4 during a closing operation of the hinge assembly 1.

A sash end of the hinge support arm 6 is pivotally connected by a connection 16 to the sash plate 2 toward the pointed end 12 of the sash plate 2. At a frame end, the hinge support arm 6 is pivotally connected by connection 18 to the frame plate 4.

The bridging support arm 10 is pivotally connected to the main support arm 8 by connection 20 and to the frame plate 4 by connection 22.

A sash end of the main support arm 8 is pivotally connected to the sash plate 2 by connection 24 at a position forward (i.e. further from the end cap 14 and closer to a leading edge of the assembly 1) of the point of connection 16 of the hinge support arm 6 to the sash plate 2. A frame end of the main support arm 8 is pivotally connected to the frame plate 4 by the connection 26 at position forward of the connection 18 of the hinge support arm 6 and the connection 22 of the bridging support arm 10 to the frame plate 4.

In exemplary friction stays, either the connection 26 of the main support arm 8 to the frame plate 4 or the connections 18, 22 of the bridging support arm 10 and hinge support arm 6 to the frame plate 4 is slidable. However, only the pitches between the connection 26 and the connections 22 and 18 (which move together, if they move) are variable and may be termed variable pitches. All other pitches between connections are fixed pitches in that they do not alter during opening and closing of the door or window and these may be termed fixed pitches.

In use, a pair of hinge assemblies comprising the hinge assembly 1 and a mirror image hinge assembly are fitted to opposed sides of a window or door. The sash plates 2 of the hinge assemblies may be attached to the top and bottom edges of a window leaf (or the sides when used in a top-hung or awning window) with the frame plates 4 attached to corresponding edges of the window frame.

As the window leaf is opened, the leading edge end 18 of the sash plate 2 is pushed outward as a user applies an outward (with respect to the building) force to the window leaf. In the exemplary arrangement of Figure 1, the main support arm 8 is only pivotally movable relative to the frame plate 4 and may not slide along the frame plate 4. Therefore, a slider 28 is pulled along the frame plate 4 toward the pivotal connection 26 of the main support arm 8 to the frame plate 4. The sash plate 2 swings outwards (clockwise in Figure 1) away from the frame plate 4. The movement of the slider 28 causes the pointed end 12 to separate from the end cap 14.

It will be understood that other arrangements of four bar friction stay hinge assembly are possible. For example, the pivotal connection 26 of the main support arm 8 may be slidable along the frame plate 4. In such arrangements, the remaining pivotal connections (i.e. the pivotal connections of the bridging support arm 10 and the hinge support arm 6 to the frame plate 4) are in fixed positions. However, in all arrangements there are fixed pitches and variable pitches, as defined above Further, the provision of a sliding connection between one or more components of the hinge assembly and the frame plate does not cause a change of geometry, since the pitches between the connections of other arms remain fixed.

To reiterate, and for the avoidance of doubt, in friction stays there are a plurality of relatively spatially fixed pivotal connections and one or two slidable pivotal connections. Where there are two slidable connections then they are typically fixed with respect to each other. Therefore, there are a plurality of fixed pitches between connections and a plurality (typically two) of variable pitches between connections.

As used herein, the term “geometry” when used in respect of friction stay hinge assemblies encompasses the fixed pitches of the friction stay. The geometry of a friction stay hinge assembly is not the specific location or orientation of each component at any particular time as this may change, for example, at various positions during opening and closing the window leaf. Rather, the geometry encompasses the fixed pitches between the connections of the support arms. In known friction stays, the geometry is fixed and, in particular, the pitches between the connections of the various elements of the friction stay are fixed. One of the connections to the frame plate will be moveable (or two connections will be moveable together), but other connections are fixed relative to each other. The moveable connection(s) are coupled to a sliding friction block.

In order to ensure the geometry of the assembly permits a reliable seating of the pointed end 12 in the end cap 14, it is desirable to have a hinge support arm 6 that is longer relative to the other support arms than that used in known friction stays. This creates a movement of the pointed end 12 away from the end cap 14 substantially along the line of the frame plate 4. The geometry used in known friction stay hinge assemblies may result in the travel of the pointed end 12 clashing with the end cap 14 over time if the geometry becomes misaligned for some reason.

It is desirable to have a friction stay that accommodates a travel of the pointed end 12 that brings it clear of the end cap 14 before it moves outwards from the window frame. The inventors have appreciated that this may be achieved by incorporating a longer hinge support arm 6, although this brings problems in that the geometry of the hinge assembly 1 is then thrown out of alignment. In exemplary arrangements, the hinge support arm may be in a range from 10% to 30% longer than a hinge support arm used in a fixed geometry having the same pitches between the other connections.

As set out in detail below, friction stays disclosed herein incorporate a pitch variation device allowing one or more fixed pitches to be varied. The pitch variation device allows one or more of the fixed (i.e. non-slidable) connections of a friction stay to be moveable relative to the other fixed connections. This builds play into the location of the connection, which can accommodate a differently sized support arm elsewhere in the friction stay hinge assembly. The pitch variation device is one exemplary way to change a geometry of a friction stay hinge assembly.

Figure 2 shows a perspective view of part of a hinge assembly 101. Many of the features of the hinge assembly 101 are the same or similar to the features of the hinge assembly 1 described above. Such features may not be described in detail again in respect of Figure 2, except where necessary to describe the operation of the hinge assembly 101, or where they differ from the corresponding feature of the hinge assembly 1. Similar feature are given the same reference numeral, except preceded by a “10”.

The hinge assembly 101 comprises a sash plate 102, a frame plate 104 and three supporting arms: the hinge support arm 106, the main support arm 108, and a bridging support arm 110 extending between the main support arm 108 and the frame plate 104. The arrangement of the hinge support arm 106, the main support arm 108 and the bridging support arm 110 is largely the same as the corresponding features of hinge assembly 1. Further, the connections 116, 118, 120, 122, 124 and 126 (not shown in Figure 2) are largely the same, except that in the exemplary arrangement of Figure 2, the connection 126 of the main support arm 108 to the frame plate 104 is slidable.

The pivotal connection 126 (shown in Figure 4) of the main support arm 108 to the frame plate 104 is slidable along the frame plate 104 via a main support arm slider 128. The remaining pivotal connections 118, 122 to the frame plate 104 are those of the hinge support arm 106 and the bridging support arm 110. Those connections are normally fixed, as is the pitch between them, in known friction stays. In the exemplary arrangement of Figure 2, the pivotal connection of the hinge support arm 106 to the frame plate is in a fixed position and the pivotal connection 122 of the bridging support arm 110 to the frame plate 104 comprises a pitch variation device 130. This allows variation of the (normally) fixed pitch between those connections during opening and closing of the hinge assembly.

The main support arm slider 128 is retained in slidable connection with the frame plate 104. In the exemplary assembly 101 of Figure 2, the main support arm slider 128 is configured to travel along a channel in the frame plate 104 during opening and closing of the hinge assembly 101. The bridging arm 110 is pivotally connected to the frame plate 104 by a carriage 132. In the exemplary assembly 101 of Figure 2, the bridging arm 110 is pivotally connected to the main support arm 108 at a mid-portion thereof.

It is noted that one or more pitch variation devices 132 may be positioned elsewhere on the friction stay in other exemplary arrangements. Further, the pitch variation devices may take other forms than that shown in the figures. For example, a pitch variation device may be located at the pivotal connection 120 of the bridging support arm 110 to the main support arm 108 or any other pivotal connection of the hinge assembly 101. Further, the pitch device may be incorporated into one or more of the supporting arms, for example by including a telescopic arrangement within the bridging support arm 110 (or any other support arm). Similarly, the same principles may be applied to other types of friction stay hinge assembly, such as a six bar friction stay hinge assembly.

The pitch variation device comprises a carriage 132 that is moveable into a first position (against the buffer 134) and a second position (against the buffer 138 and shown in Figure 2).

The main support arm slider 128 and carriage 132 of the pitch variation device are configured to slide along the frame plate 104 during opening and closing operations of the hinge assembly 101. The carriage 132 is independently slidable along the frame plate 104. That is, the carriage 132 is not coupled either to the pivotal connection 126 of the main support arm 108 to the frame plate 104 or the pivotal connection 118 of the hinge support arm 106 to the frame plate 104. The pivotal connection 122 of the bridging support arm 110 to the frame plate is therefore independently moveable along the frame plate 104 and can move at a different, or independent, rate than the pivotal connection 126 of the main support arm 108 to the frame plate 104 or the pivotal connection 118 of the hinge support arm 106 to the frame plate 104.

In the exemplary assembly 101 of Figure 2, the connection of the hinge support arm 106 to the frame plate 104 is at a fixed position. The connection of the main support arm 108 to the frame plate 104 is slidable by virtue of the main support arm slider 128.

The frame plate 104 comprises a first buffer 134. The first buffer 134 is prevented from moving on the frame plate 104 by a projection 136 on the frame plate, which retains the first buffer 134 in position. The first buffer 134 limits the movement of the carriage 132 towards the leading edge end of the assembly 101. In addition, a second buffer 138 is provided by an end face of a fixing of the connection 118 of the hinge support arm 106 to the frame plate 104. The second buffer 138 limits the movement of the carriage 132 towards the hinge end of the assembly 101.

The carriage 132 can be moved between two terminal positions defined by the first and second buffers 134, 138. A first position is when the carriage 132 abuts the first buffer 134 and a second position is when the carriage 132 abuts a second buffer 138, which in the exemplary assembly 101 of Figure 2 is provided by a part of the connection between the hinge support arm 106 and the frame plate 104.

The independent movement of the carriage 132 permits the pitch variation device 130 to accommodate an increase in a length of the hinge support arm 106. Movement of the carriage 132 between first and second positions also represents a change in geometry of the hinge assembly 101, as the otherwise fixed pitch between the connection 118 and 122 is altered.

It may be possible for the carriage 132 to move without requiring the main support arm slider 128 to move. This may be the case for at least part of the opening or closing operation of the window. Specifically, it may be the case for an initial opening movement and a final closing movement. In exemplary arrangements, the initial opening movement may encompass movement of a window from a fully closed position to an angle of opening up to 10 degrees. Similarly, the final closing movement may encompass movement of the window from an angle of 10 degrees or less to a fully closed position. Since the support arms are all pivotally connected, this movement will cause some movement in one or more of the other components of the hinge assembly 101.

Because the hinge assembly 101 includes a pitch variation device, it is possible to use a longer hinge support arm 106 than a friction stay with a fixed geometry would be able to incorporate. It is noted that in other exemplary arrangements, a differently positioned pitch variation device may be able to accommodate use of other support arms having varying lengths.

Figure 3 shows the hinge assembly 101 in cross-section in its fully closed position. The sash and frame plates 102, 104 and the three supporting arms 106, 108, 110 are all in parallel and adjacent. Due to the length of the hinge support arm 106, when in the closed position, the carriage 132 is pulled toward the buffer 134, overcoming the bias of the biasing means 140, which in the exemplary arrangement is a spring.

It is noted that exemplary window assemblies may not require the sash plate 102 and the frame plate 104 and that other features may be used to permit connection to a sash or frame and/or slidable connection to a frame.

The method of operation will now be described with reference to Figures 2 to 4.

In the closed position, the main support arm slider 128 is pushed as far as it can travel towards the leading edge end of the frame plate 104. As the bridging support arm 110 is pivotally connected to the main support arm, the carriage 132 is moved into its first position against the first buffer 134 and the biasing force of the spring 140 is overcome.

During an opening operation, the window leaf (not shown) and thus the leading edge end of the sash plate 102 is pushed outwards substantially in the direction D. The sash plate 102 initially pivots around the locating end 112, then as the sash plate 102 continues to move outwards (in the direction D) the pivotal connection 124 between the sash plate 102 and main support arm 108 moves away from the frame plate 104. The main support arm slider 128 is drawn toward the hinge end of the frame plate 104 i.e. toward the end cap 114. This motion releases the force on the carriage 132 that has overcome the biasing force of the spring 140. The spring 140 therefore biases the carriage 132 towards the second buffer 138 and into its second position. The pointed end 112 is therefore withdrawn from the end cap 114. The pitch variation device 130 therefore prevents the pointed end 112 from clashing with the saddle 114, which would otherwise happen because the hinge support arm is incorrectly dimensioned, e.g. is too long.

During a closing operation, the sash plate 102 is pulled toward the frame plate 104 by a user pulling on a window leaf to which the hinge assembly 101 is attached in the direction C. The supporting arms 106, 108, 110 pivot accordingly to permit the movement and rotation of the sash plate 102. The biasing force of the spring 140 is sufficient to retain the carriage 132 in the second position during the majority of the closing operation. The main support arm slider 128 continues to travel away from the end cap 114. In this way, the pointed end 112 of the sash plate 102 is able to approach the saddle 114 without clashing with it because the carriage 132 is in the second position. As the window leaf enters the final stage of the closing operation, the main support arm slider 128 is pushed as far as it may travel along the frame plate 104 away from the end cap 114 by the moving sash plate 102. As the force applied to the main support arm slider 128 is now substantially aligned with the spring 140, the bias of the spring 140 is overcome and the carriage 132 is moved back to its first position against the first buffer 134. By having the carriage 132 in its first position until the pointed end 112 has approached the end cap 114 to a sufficient degree, clashing is avoided. The carriage 132 must then be allowed to move to its first position to accommodate the incorrect length of the hinge support member 106.

By permitting movement of the carriage 132 relative to the frame plate 104, the hinge assembly 101 can accommodate the use of a hinge support arm 106 which is longer than that optimised for a friction stay having a fixed geometry.

In alternative arrangements, the main support arm may be pivotally connected to the frame plate at a fixed position and does not slide. Instead, both the hinge support arm and the bridging support arm are connected to the frame plate by hinge support arm and bridging support arm sliders. In such arrangements, the hinge support arm and bridging support arm sliders are, at least partially, independently movable. In this sense, independent movement encompasses simultaneous movement in the same direction, but at a different rate and/or by a different amount. The buffer may be omitted in order to permit sufficient travel. The carriage may comprise a biasing means to bias the carriage independently of the hinge support arm slider in order to modify the geometry of the hinge assembly as in figures 2-4.

The skilled person will be able to envisage further embodiments of the invention without departing from the scope of the appended claims.

Claims

CLAIMS:

1. A friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising:

a plurality of support arms each pivotally connected to one or more other of the support arms, to a sash plate and/or to a frame plate to form a friction stay, wherein the pivotal connections provide a plurality of fixed pitches between connections; and characterised by a pitch variation device configured to allow variation of one or more of the fixed pitches during opening and closing of the hinge assembly.

2. A hinge assembly according to claim 1, wherein a plurality of support arms are pivotally connected to the frame plate, and wherein the pitch variation device forms part of a first pivotal connection to the frame plate and is configured to allow the first pivotal connection to move between first and second positions on the frame plate.

3. A hinge assembly according to claim 2, wherein at least one other of the pivotal connections of the plurality of support arms to the frame plate is slidable along the frame plate during normal opening and closing the window leaf.

4. A hinge assembly according to claim 2 or 3, wherein the pitch variation device is configured to permit movement of the first pivotal connection during an opening and/or a closing operation of the hinge assembly.

5. A hinge assembly according to any of claims 2 to 4, wherein the pitch variation device comprises a carriage moveable between the first and second positions.

6. A hinge assembly according to any of claims 2 to 5, further comprising a biasing means for biasing the pitch variation device into the second position.

7. A hinge assembly according to any of claims 2 to 6, wherein the pitch variation device forms part of a bridging support arm pivotal connection to the frame plate, and is configured to allow independent movement of the bridging support arm pivotal connection and a hinge support arm pivotal connection to the frame plate.

8. A hinge assembly according to claim 7, wherein when the pitch variation device is in the first position the bridging support arm pivotal connection is further away from the hinge support arm pivotal connection, as compared to when the pitch variation device is in the second position.

9. A hinge assembly according to claim 7 or 8, wherein a main support arm is pivotally connected to the frame plate and is slidable along the frame plate during normal opening and closing the window leaf.

10. A hinge assembly according to claim 9, wherein the bridging support arm is also pivotally connected to the main support arm.

11. A hinge assembly arm according to claim 10, wherein the hinge support arm is in a range from 10% to 30% longer than a hinge support arm for a hinge assembly having a fixed geometry.

12. A hinge assembly according to any of claims 9 to 11, wherein the hinge support arm and the main support arm comprise pivotal connections to a sash plate.

13. A hinge assembly according to any preceding claim, wherein the hinge assembly is one of a four bar friction stay or a six bar friction stay.

14. A friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising:

a sash plate for fitting to the window leaf; a frame plate for fitting to the window frame;

a main support arm pivotally connected to the sash plate and the frame plate, the pivotal connection to the frame plate being slidable along the frame plate for opening and closing the window leaf;

a hinge support arm pivotally connected to the sash plate and the frame plate; a bridging support arm pivotally connected to the main support arm and the frame plate; and a pitch variation device for varying a pitch between the pivotal connection of the bridging support arm to the frame plate and the pivotal connection of the hinge support arm to the frame plate.

15. A friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising:

a frame plate for fitting to the window frame; and 5 a plurality of support arms forming a friction stay, wherein at least three of the support arms are pivotally connected to the frame plate, and wherein at least two of the at least three pivotal connections are slidable along the frame plate on opening and/or closing of the friction stay hinge assembly.

10

16. A friction stay hinge assembly for a window, the window comprising a window leaf and a corresponding window frame, the hinge assembly comprising:

a frame plate for fitting to the window frame; a sash plate for fitting to the window leaf; and a plurality of support arms connected at pivotal connection points to the frame 15 plate, the sash plate and/or another of the support arms to form a friction stay, wherein the frame plate, sash plate and support arms are configurable in first and second geometries.

17. A window assembly comprising a window leaf, a window frame and a hinge 20 assembly according to any preceding claim.

18. A friction stay hinge assembly substantially as described herein and with reference to Figures 2 to 4.

Intellectual

Property

Office

Application No: GB1611716.0 Examiner: Mr Haydn Gupwell