GB2551992A

GB2551992A - Protecting link for window stay

Info

Publication number: GB2551992A
Application number: GB1611649.3A
Authority: GB
Inventors: William Edmonds Tracy
Original assignee: Era Home Security Ltd
Current assignee: Era Home Security Ltd
Priority date: 2016-07-04
Filing date: 2016-07-04
Publication date: 2018-01-10
Also published as: GB201611649D0

Abstract

A friction stay hinge assembly 200 for a casement window, the casement window comprises a window leaf and a window frame. The hinge assembly 200 has a main support arm 206 and a bridging support arm 208 pivotally connected to the main support arm 206. The main support arm 206 and bridging support arm 208 are configured for arrangement between the window leaf and the window frame. At least one of the main support arm 206 and bridging support arm 208 is slidably connectable to the window frame for opening and closing of the window leaf with respect to the window frame. The bridging support arm 208 is configured to take part of an axial load applied to the main support arm 206 during opening and closing of the window leaf with respect to the window frame. The invention prevents damage occurring to the main support arm 206.

Description

(54) Title of the Invention: Protecting link for window stay Abstract Title: Protecting Link for Window Stay (57) A friction stay hinge assembly 200 for a casement window, the casement window comprises a window leaf and a window frame. The hinge assembly 200 has a main support arm 206 and a bridging support arm 208 pivotally connected to the main support arm 206. The main support arm 206 and bridging support arm 208 are configured for arrangement between the window leaf and the window frame. At least one of the main support arm 206 and bridging support arm 208 is slidably connectable to the window frame for opening and closing of the window leaf with respect to the window frame. The bridging support arm 208 is configured to take part of an axial load applied to the main support arm 206 during opening and closing of the window leaf with respect to the window frame. The invention prevents damage occurring to the main support arm 206.

FIG. 2

PB149770GB

1/1

203

FIG. 2

33216601-2-DWOLSTENHOLME

Protecting Link for Window Stay

Technical Field

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

Background

Reference is made herein to a friction stay hinge assembly for a casement window and it is noted that the features of such hinge assemblies may apply equally to a door or hatch hinge assembly.

Casement windows typically comprise one or more movable window leafs and a window frame fitted into an aperture in a wall. A variety of different hinges for casement windows are available on the market depending on the size and strength required, one of which is known as a friction stay hinge, for example a four bar friction stay hinge or a six bar friction stay hinge. Other terms may be used in the art, such as a four bar or six bar stay, or a four bar or six bar hinge.

Friction stays are known in the art and typically comprise a main support arm connected between a window leaf and a window frame, a bridging support arm connected between the main support arm and the window frame and a smaller hinge support arm connected between the window leaf and the window frame. The operation of a friction stay is discussed below with reference to Figure 1.

For both side hung and top hung casement windows, it is desirable for the window to remain in position once opened. Thus, friction stay hinge assemblies often include friction joints or friction sliders configured to resist movement, but which can be slid if the friction force is overcome by a user operating the window or door.

It is also desirable that the window leaf and the window frame form a close seal, preferably a watertight seal, in order to prevent ingress of water or airflow. Commonly, compression seals are used around the periphery of the window leaf to provide a satisfactory seal. In order for the compression seals to be effective, the window leaf must be held sufficiently tightly against the frame to compress the seals and retain them in their compressed state.

As friction stay hinge assemblies age, it is known for the performance to deteriorate. This may result in a reduction in the amount of compression applied to the seal. Furthermore, as wear builds up, the geometry of the hinge assemblies can become misaligned, which may increase the forces experienced by one or more of the support arms in the friction hinge assembly, which in turn may lead to damage to those or other elements of the assembly. Further, if one or more sliding friction blocks of a friction stay becomes impeded in its travel along a track fitted to the window frame, such as by an obstruction, then a user of the window may apply excessive force in order to close the window. This may lead to undue stress on one or more elements of the friction stay and may result in damage to the friction stay.

It is therefore desirable to provide a friction stay hinge assembly which overcomes or ameliorates one or more of the above problems, or provides an alternative.

Summary

According to the invention in a first aspect, there is provided a friction stay hinge assembly for a casement window, the casement window comprising a window leaf and a window frame, the hinge assembly comprising: a main support arm and a bridging support arm pivotally connected to the main support arm, the main support arm and bridging support arm configured for arrangement between the window leaf and the window frame, wherein at least one of the main support arm and bridging support arm is slidably connectable to the window frame for opening and closing of the window leaf with respect to the window frame, and wherein the bridging support arm is configured to take part of an axial load applied to the main support arm during opening and closing of the window leaf within the window frame.

In accordance with aspects of the invention, the bridging support arm is configured to reduce the amount of axial load through the main support arm, in particular during closing of the window leaf. This provides advantages in respect of resisting buckling of the main support arm during high loading conditions.

As used herein, the term “buckling” encompasses deformation or even failure of a component due to a force or load applied on a component. For example, the bridging support arm may be configured to resist a lateral deformation or failure or deformation caused by a compressive axial force applied on the main support arm.

It is noted that friction stay hinge assemblies disclosed herein need not include a sash plate, frame plate and/or hinge support arm. The main support arm and bridging support arm may be connected directly to the window leaf and/or window frame and this may still fall within the scope of the invention as claimed.

Optionally, the bridging support arm is configured to extend from the main support arm such that an angle between the main support arm and the bridging support arm facing the window frame is acute during at least part of a travel of the window leaf during opening and closing.

Optionally, the bridging support arm is configured such that the angle between the main support arm and the bridging support arm facing the window frame is substantially zero when the window leaf is in a closed position.

Optionally, the bridging support arm is configured to extend from the main support arm such that the angle between the main support arm and the bridging support arm facing the window frame is acute at all times during opening and closing of the window leaf. It is noted that the acute angle may actually be substantially zero degrees when the window leaf is fully closed, as the main support arm and the bridging support arm may be adjacent and aligned.

Optionally, the bridging support arm is configured to extend from the main support arm such that the angle between the main support arm and the bridging support arm facing the window frame is less than: 80 degrees; 60 degrees; or 45 degrees at all times during opening and closing of the window leaf.

Optionally, the bridging support arm is configured to extend from the main support arm and connect to the window frame such that an angle between the bridging support arm and the window frame facing a hinge end of the window frame is acute during at least part of a travel of the window leaf during opening and closing.

Optionally, the hinge assembly is configured such that the connection of the bridging support arm to the main support arm is closer to the hinge end of the window leaf than the connection of the bridging support arm to the window frame when the window leaf is closed.

Optionally, the hinge assembly is configured such that when the hinge assembly is fitted to a casement window the connection of the bridging support arm to the main support arm is closer to the window leaf than the window frame.

Optionally, the bridging support arm is slidably connectable to the window frame.

Optionally, the hinge assembly is configured when fitted to the casement window such that the connection of the bridging support arm to the window frame and the connection of the main support arm to the window frame become closer together during a closing operation of the hinge assembly.

Optionally, the hinge assembly further comprises a frame plate for connection to the window frame, wherein the main support arm and the bridging support arm are connected to the frame plate.

Optionally, the main support arm is pivotally connected to the frame plate at a fixed point.

Optionally, the bridging support arm is slidably and pivotally connected to the frame plate.

Optionally, the hinge assembly further comprises a sash plate for connection to the window leaf, wherein the main support arm is connected to the sash plate.

Optionally, the main support arm is pivotally connected to the sash plate at a fixed point.

Optionally, the hinge assembly further comprises a hinge support arm connected between the sash plate and the frame plate.

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

According to another aspect of the invention there is provided a casement window assembly comprising at least one friction stay hinge assembly as disclosed herein.

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 friction stay hinge assembly; and Figure 2 is a plan view of a friction stay hinge assembly.

Specific Description

Generally disclosed herein are friction stay hinge assemblies in which the bridging support arm, which is connected between the main support arm and the window frame (optionally via a frame plate), is arranged to take some of a compressive load exerted on the main support arm during closing of the window leaf. In exemplary embodiments, this is achieved by the main support arm and the bridging support arm diverging to form a fork from the connection point of the bridging support arm towards the window frame. The angle of the fork is an acute angle and may be less than 45 degrees during at least part of the opening or closing of the window leaf. In this way, some of the axial load experienced by the main support arm is transferred to the bridging support arm.

Figure 1 shows a friction stay hinge assembly 100. The exemplary hinge assembly of Figure 1 is a six bar hinge assembly. The hinge assembly 100 comprises a sash plate (also known as a fourth link) 102 for supporting a window leaf and a frame plate (also known as a track) 104 for fixing to a window frame. The sash plate 102 (and therefore the window leaf when it is attached) is moveable with respect to the frame plate 104 (and therefore the frame when it is attached) based on the geometry of other features of the assembly that are connected between the sash plate 102 and the frame plate 104, as discussed below.

The assembly 100 has a leading edge end 103, and a hinge end 105. The sash plate 102 and frame plate 104 are connected by an assembly of five supporting arms including a main support arm (also known as a third link) 106, a bridging support arm 108, an adjacent support arm (also known as a second link) 110, a hinge support arm (also known as a first link) 112 and an interlinking arm 114.

Beginning at the hinge end 105 of the assembly 100, the hinge support arm 112 is pivotally connected to the sash plate 102 and the frame plate 104. The connection of the hinge support arm 112 to the sash plate 102 is in a fixed position. The connection of the hinge support arm 112 to the frame plate 104 is slidable along the frame plate

104.

Further towards the leading edge end 103, the parallel support arm 110 is pivotally connected to the main support arm 106 and pivotally connected to the frame plate 104. The pivotal connection of the parallel support arm 110 to the main support arm 106 is in a fixed position. The pivotal connection of the parallel support arm 110 to the frame plate 104 is slidable along the frame plate 104. The parallel support arm 110 is pivotally, slidably connected to the frame plate 104 at a first friction slider 116 configured to move within a track on the frame plate 104. The hinge support arm 112 is also pivotally, slidably connected to the frame plate 104 at the first slider 116.

Further along the frame plate 104 towards the leading edge end 103, the bridging support arm 108 is pivotally connected to the frame plate 104 and to the main support arm 106. The pivotal connection of the bridging support arm 108 to the main support arm 106 is in a fixed position. The connection of the bridging support arm 108 to the frame plate 104 is slidable along the frame plate 104. The bridging support arm 108 is pivotally, slidably connected to the frame plate 104 at a second slider 118 configured to move within a track on the frame plate 104.

Further along the frame plate 104 towards the leading edge end 103, the main support arm 106 is pivotally connected to the frame plate 104 and the sash plate 102. Both pivotal connections of the main support arm 106 are at a fixed position.

The interlinking arm 114 is pivotally connected to the sash plate 102 at a point between the connections of the main support arm 106 to the sash plate 102 and the hinge support arm 112 to the sash plate 102. The interlinking arm 114 is also pivotally connected to the parallel support arm 110 at a point between the connections of the main support arm 106 to the parallel support arm 110 and the frame plate 104 to the parallel support arm 110. The parallel support arm 110 runs substantially parallel to the sash plate 102.

The bridging support arm 108 is connected to the main support arm 106 at a point between its connections to the sash plate 102 and frame plate 104. The parallel support arm 110 is connected to the main support arm 106 at a point between the connection of the main support arm 106 to the bridging support arm 108 and the connection of the main support arm 106 to the sash plate 102.

In the friction stay hinge assembly 100 of Figure 1, the bridging support arm 108 provides little to no structural support to the assembly 100, rather the bridging support arm 108 and second slider 118 provide a second friction slider connection to the frame plate 104 and point of resistance to the movement of the hinge assembly 100. Any compressive load experienced by the main support arm 106 is transverse to the longitudinal direction of the bridging support arm 108 and so none of the compressive load is taken by the bridging support arm 108.

The amount of force required to open/close the assembly can be controlled by a manufacturer of the friction stay hinge assembly 100. This is desirable so that a window unit comprising the hinge assembly 100 remains in place when opened, and is not affected by, for example, wind, but can be easily adjusted or closed by a user by simply pushing or pulling the window leaf without requiring the actuation of a latch or lock mechanism.

In the hinge assembly 100 of Figure 1, the bridging support arm 108 extends from the main support arm 106 at an angle toward the hinge end 105 of the frame plate 104.

That is, from the connection of the bridging support arm 108 to the main support arm 106, the bridging support arm 108 extends towards the frame plate 104 and towards the hinge end of the frame plate 104. In the exemplary apparatus of Figure 100, the bridging support arm 108 is connected to the second slider 118 at a position closer to the hinge end 105 than the leading edge end 103 of the frame plate 104, relative to the position A. Position A is the position on the frame plate 104 at which a line normal to the frame plate 104 and passing through the connection between the main support arm 106 and the bridging support arm 108 hits the frame plate. It is noted that this point moves during opening and closing of the window leaf, but the bridging support arm 108 is always connected to the second slider 118 at a position closer to the hinge end 105 than the leading edge end 103 of the frame plate 104, relative to the position A. In other words, an angle Θ between the bridging support arm 108 and the frame plate 104 (or window frame) and facing the leading edge end 103 is acute during at least part of the opening and closing of the window leaf and possibly throughout the opening and closing of the window leaf.

As shown, the hinge assembly 100 is in an open position. During closing, the sash plate 102 is moved towards the frame plate 104 until it is aligned directly adjacent (above in vertically hinged windows) the frame plate 104. During the closing operation, the first and second sliders 116 and 118 will be moved toward the hinge end 105 of the assembly 100 as the main support arm 106 rotates about its pivotal connection to the frame plate 104 to align therewith. The angle Θ will decrease to substantially zero when all the support arms are parallel and are aligned.

At all positions of the sash plate 102 during closing of the window leaf, the angle θ is less than 90°. As the sash plate 102 (and therefore the window leaf if it is attached) is pulled toward the frame plate 104, the sash plate 102 rotates in an opposite direction to the main support arm 106 (anti-clockwise with respect to Figure 1) and travels toward the hinge end 105 of the assembly 100. It is understood that in window assemblies wherein a pair of hinge assemblies 100 are provided, the assembly on the opposite side of the window leaf will be mirrored compared to the hinge assembly 100 in Figure 1.

The inventors have appreciated that a weakness of the hinge assembly 100 is that as the assembly 100 and the window frame to which it is attached age, slight warping and distortion may occur. In such circumstances, it is possible that a locating end 120 of the sash plate 102 may not align with a saddle 122 of the frame plate 104. Alternatively, the saddle 122 may become blocked preventing proper seating of the locating end therein and therefore preventing proper alignment of the features of the hinge assembly 100. For example, the locating end 120 may clash with the edge of the saddle 122 or a frame to which the assembly 100 is attached.

When the misalignment discussed above occurs, it may not be possible for the sash plate 102 to travel fully to the hinge end 105, and the sash plate 102 cannot be positioned fully parallel to (i.e. directly above on a vertically hinged window) the frame plate 104. When this occurs, the hinge assembly 100 is stuck in a partially open position. If stuck open, users are prone to forcing the mechanism in order to close the window, potentially causing damage to one or more features of the hinge assembly 100. Particularly vulnerable is the main support arm 106, which may buckle or bend under the increased forces exerted on it due to misalignment of the hinge assembly 100. Typically, when the hinge assembly 100 is prevented from closing properly, an increased axial (e.g. longitudinal and compressive) force is applied to the main support arm 106, which is then prone to buckling.

Figure 2 shows a further friction stay hinge assembly 200. One or more features of the hinge assembly 200 are the same or similar to the friction stay hinge assembly 100. Such features are not described in detail again and are given like reference numerals, except prefixed by a “2”. Attention is focussed on describing some of the features of Figure 2 that are different to those in Figure 1.

The main support arm 204 is pivotally connected to the sash plate 202 at position 224. Position 224 is spaced away from the distal end of the sash plate by distance 226.

The bridging support arm 208 is pivotally connected to the main support arm 206 at a fixed position, which is closer to the sash plate 202 than to the frame plate 204. In exemplary hinge assemblies, the connection of the bridging support arm 208 to the main support arm 206 is at least halfway along the length of the main support arm 206 from the frame plate 204 towards the sash plate 202. This permits a longer bridging support arm 206. Further, connecting the bridging support arm 208 to the main support arm 206 at a point closer to the sash plate 202 exposes a reduced length of the main support arm 206 to the increased axial loads discussed above before some of the axial load is taken by the bridging support arm 208. This reduces the risk of buckling of the main support arm 206 above the connection to the bridging support arm 208.

The bridging support arm 208 is connected to a second slider 218 on the frame plate 204 at a position closer toward the leading edge end 203 than the hinge end 205 relative to the position A, which is defined above. The bridging support arm 208 thus has a reverse orientation compared to the hinge assembly in Figure 1. From its connection to the main support arm 206, the bridging support arm 208 extends towards the leading edge end 203 of the frame plate 204, such that it extends in a direction towards the frame plate 204 and a leading edge end 203.

The angle between the main support arm 206 and the bridging support arm 208 facing the frame plate 204 is acute at least partway through an opening or closing operation of the window leaf. In exemplary embodiments, the angle between the main support arm 206 and the bridging support arm 208 facing the frame plate 204 is always acute. Further, when the window is closed, the angle between the main support arm 206 and the bridging support arm 208 facing the frame plate 204 is substantially zero degrees. This is in contrast to the hinge assembly of Figure 1 where the same angle is 180 degrees when the window leaf is closed. In exemplary embodiments, the angle between the main support arm and the bridging support arm facing the window frame is less than: 80 degrees; 60 degrees; or 45 degrees at all times during opening and closing of the window leaf.

Correspondingly, the angle θ between the bridging support arm 208 and the frame plate 204 facing the leading edge end 203 is always be greater than 90° for all positions of the hinge assembly 200 as it is opened and closed. Further, the opposite angle (facing the hinge end 205) is always acute, or less than 90 degrees.

When the window leaf is closed, the connection of the bridging support arm 208 to the main support arm 206 is closer to the hinge end 205 of the frame plate 204 than the connection of the bridging support arm 208 to the frame plate 204 when the window leaf is closed.

During closing of the hinge assembly, the second slider 218 is pushed toward the leading edge end 203 of the hinge assembly.

Hinge assembly 200 is designed with a degree of “selective misalignment” i.e. the main support arm 206 is longer than the length required for the “ideal geometry”. The ideal geometry is the relative arrangement of components which allows the hinge assembly to open and close smoothly without stress being applied on any component. There may be more than one ideal geometry, as the ideal geometry represents an optimal arrangement for a given set of components. Equally, the components may be connected in more than one arrangement to achieve the same effect.

By using selective misalignment of the main support arm 206, on closing the hinge assembly 200, it is necessary to impart an axial compressive force along the main support arm 206 during the final stages of closing the window leaf. This ensures a good compressive seal around the window leaf and the window frame. The main support arm 206 might be resiliency flexible and the resilience can be used to impart a force on the hinge assembly 200. For example, when the hinge assembly 200 is closed, the compressed main support arm 206 will want to expand, thereby pressing the locating end 220 into the saddle 222. Further, this force can be used to apply a compressive force onto a casement window assembly e.g. in order to compress a compression seal and improve the weather resistance of the window assembly.

Should the locating end 220 not be properly received in the saddle 222, the assembly 200 and particularly the main support arm 206 could become damaged during closing. The “reverse orientation” of the bridging support arm 208 of the hinge assembly 200 is advantageous, since it has been found to be more resistant to accidental bending or buckling of the main support arm 206 or other components of the hinge assembly 200 during closing of the sash plate 202. This is especially the case in the situation where the locating end 220 fails to be properly seated in the saddle 222. In circumstances where the locating end 220 is unable to seat correctly in the saddle 222, the hinge assembly 200 will be nearly fully closed. Thus, when nearly fully closed, the bridging support arm 208 and the main support arm 206 will be almost parallel, and an axial force applied to the main support arm will be shared between the main support arm 206 and the bridging support arm 208. Further, the bridging support arm 208 can be connected to the main support arm 206 at a potentially weak point where it is prone to buckling, thereby directly supporting the main support arm 206. Thus, even if misaligned, the force applied to the main support arm 206 is less than the maximum force it can withstand before bending or deforming.

In exemplary arrangements, the bridging support arm 208 may be configured to take up to 50% of the axial load through the main support arm 206 during closing. In other arrangements, the bridging support arm 208 may be configured to take: from 10% to 50%; from 20% to 50%; from 30% to 50%; or from 40% to 50% of the axial load.

It is noted that further exemplary embodiments may be envisaged without departing from the scope of the appended claims. For example, exemplary arrangements are shown using a six bar friction stay, but the principles may be applied to other friction stays, such as a six bar friction stay. Further, other arrangements of friction stay are possible, in which other connections to the frame plate 204 are slidable for opening and closing the window leaf.

Claims

CLAIMS:

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

a main support arm and a bridging support arm pivotally connected to the main support arm, the main support arm and bridging support arm configured for arrangement between the window leaf and the window frame, wherein at least one of the main support arm and bridging support arm is slidably connectable to the window frame for opening and closing of the window leaf with respect to the window frame, and wherein the bridging support arm is configured to take part of an axial load applied to the main support arm during opening and closing of the window leaf with respect to the window frame.

2. A hinge assembly according to claim 1, wherein the bridging support arm is configured to extend from the main support arm such that an angle facing the window frame between the main support arm and the bridging support arm is acute during at least part of a travel of the window leaf during opening and closing.

3. A hinge assembly according to claim 2, wherein the bridging support arm is configured such that the angle facing the window frame between the main support arm and the bridging support arm is substantially zero when the window leaf is in a closed position.

4. A hinge assembly according to claim 2 or 3, wherein the bridging support arm is configured to extend from the main support arm such that the angle facing the window frame between the main support arm and the bridging support arm is acute at all times during opening and closing of the window leaf.

5. A hinge assembly according to claim 4, wherein the bridging support arm is configured to extend from the main support arm such that the angle facing the window frame between the main support arm and the bridging support arm is less than: 80 degrees; 60 degrees; or 45 degrees at all times during opening and closing of the window leaf.

6. A hinge assembly according to any preceding claim, wherein the bridging support arm is configured to extend from the main support arm and to connect to the window frame such that an angle facing a hinge end of the window frame between the bridging support arm and the window frame is acute during at least part of a travel of the window leaf during opening and closing.

7. A hinge assembly according to any preceding claim, configured such that the connection of the bridging support arm to the main support arm is closer to the hinge end of the window frame than the connection of the bridging support arm to the window frame when the window leaf is closed.

8. A hinge assembly according to any preceding claim, configured such that when the hinge assembly is fitted to a casement window the connection of the bridging support arm to the main support arm is closer to the window leaf than the window frame.

9. A hinge assembly according to any preceding claim, wherein the bridging support arm is slidably connectable to the window frame.

10. A hinge assembly according to any preceding claim, configured when fitted to the casement window such that the connection of the bridging support arm to the window frame and the connection of the main support arm to the window frame become closer together during a closing operation of the hinge assembly.

11. A hinge assembly according to any one of the preceding claims, further comprising a frame plate for connection to the window frame, wherein the main support arm and the bridging support arm are connected to the frame plate.

12. A hinge assembly according to claim 11, wherein the main support arm is pivotally connected to the frame plate at a fixed point.

13. A hinge assembly according to claim 11 or 12, wherein the bridging support arm is slidably and pivotally connected to the frame plate.

14. A hinge assembly according to any preceding claim, further comprising a sash plate for connection to the window leaf, wherein the main support arm is connected to the sash plate.

5

15. A hinge assembly according to claim 14, wherein the main support arm is pivotally connected to the sash plate at a fixed point.

16. A hinge assembly according to any claim 14 or 15 when dependent on any of claims 11 to 13, further comprising a hinge support arm connected between the sash

10 plate and the frame plate.

17. The hinge assembly according to any one of the preceding claims, wherein the hinge assembly is one of a four bar friction stay and a six bar friction stay.

15

18. A casement window assembly comprising at least one hinge assembly according to any one of the preceding claims.

19. A hinge assembly substantially as described herein and with reference to Figure 2.

Intellectual

Property

Office

Application No: GB1611649.3 Examiner: Mr Haydn Gupwell