GB2325961A - Friction stay - Google Patents

Abstract

In a friction stay for a closure such as a window, particularly one with a profiled channel at its edge formed with lips, the arm of the stay which is mounted on the closure is formed with means such as L-section members 32 which are received in the channel and which resist removal of the arm from the channel on attempted forced entry. The members 32 may alternatively have a T-section. In another embodiment mushroom-headed pins on the arm may engage in keyhole-shaped slots in the closure.

Description

FRICTION STAYS The invention relates to friction stays and to closures incorporating such stays.

A friction stay comprises an elongate base member and an elongate arm connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a position in which the arm overlies the base member and a position in which the arm is spaced to one side of the base member and is angled relative to the base member.

A pair of such stays are normally connected between a frame and a leaf of a closure to guide the leaf in opening and closing movement out of and into the frame.

The arm is normally connected to the leaf by screws passing through holes in the arm and into the leaf. It is a problem that, on forced entry, a lever is normally inserted between the leaf and the frame to pull the leaf away from the frame.

The effect of this can be to twist the stay about its length which in turn tends to pull the screws out of the leaf and so break the connection between the stay and the leaf. The leaf can then be readily removed for access.

According to the invention there is provided a friction stay comprising an elongate base member and an elongate arm connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a position in which the arm overlies the base member and a position in which the arm is spaced to one side of the base member and is angled relative to the base member, the arm including attachment means for inter-engagement with a formation on a mounting surface.

By utilizing inter-engaging attachment means, the separation of the arm from the leaf is resisted on forced entry.

The invention also includes within its scope a closure comprising a leaf closable into and out of a frame, the leaf being connected to the frame by at least one friction stay comprising an elongate base member connected to the frame and an arm connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a position in which the arm overlies the base member when the leaf is closed into the frame and a position in which the arm is spaced to one side of the base member and is angled relative to the base member which the leaf is opened out of the frame, the arm and the leaf including interengaging attachment means for connecting the arm to the leaf.

The following is a more detailed description of an embodiment of the invention, by way of example, reference being made to the accompanying drawings in which: Figure 1 is a plan view of a window stay including a base member and an arm with the arm spaced to one side of the base member, Figure 2 is a perspective view from above and to one side of the arm of the friction stay of Figure 1, Figure 3 is a cross-sectional view through a part of a leaf of a window showing a channel formed in the leaf and showing also the arm of Figure 2 in a first position in engagement of the arm with the channel, the remainder of the friction stay being omitted for clarity, Figure 4 is a similar view to Figure 3 but showing a second stage in the engagement, Figure 5 is a similar view to Figures 3 and 4 but showing the arm fully engaged with the channel, and Figure 6 is a perspective view from above and to one side of an alternative form of arm which can be incorporated in a stay of the kind shown in Figure 1, together with part of an associated leaf on which the arm is mountable.

Referring first to Figure 1, the friction stay comprises an elongate base member 10 provided with two parallel channels 11 extending along respective side edges of the base member 10.

A linkage indicated generally at 12 connects the base member 10 to an arm 13. The linkage comprises a longer link 14, an intermediate link 15 and a shorter link 16.

One end of the longer link 14 is pivotally connected by a rivet 17 to the base member 10 towards one end of the base member 10. The other end of the longer link 14 is pivotally connected by a rivet 18 to the arm 13, intermediate the ends of the arm 13.

A slider 19 is carried by the base member 10 and has sides engaging in respective channels 11 to guide the slider 19 for sliding movement to and fro along the base member 10. The intermediate link 15 has one end pivotally connected by a rivet 20 to the slider 19 and the other end pivotally connected by a rivet 21 to a point intermediate the ends of the longer link 14.

The shorter link 16 has one end pivotally connected by a rivet 22 to the slider 19 and has the opposite end pivotally connected by a rivet 23 to a point on the arm adjacent an end 24 of the arm which is triangularly shaped.

The base member 10 is provided with fixing holes 25 and has an end cap 26 at one end for receipt of the pointed end 24 of the arm 13 in a manner described below.

Referring now additionally to Figure 2, the arm 13 is formed from a strip of material with a pair of spaced parallel flat surfaces one of which is seen at 28. The arm has a centre line 29 best seen in Figure 1. The surface 28 remote from the base member 10 carries a pair of projecting blocks 30. One block 30 is adjacent the pointed end 24 of the arm 13 and the other block 30 is adjacent the end of the arm 13 opposite the pointed end 24.

As seen in Figure 2, each projecting block 30 is generally Lshaped with a first member 31 projecting upwardly from the surface 28 of the arm 13 and a second member extending from the edge of the first member 31 remote from the surface 28 and overlying the surface 28, to form with the surface 28 a groove 33 extending parallel to the centre line 29 of the arm 13 and spaced to one side of the centre line 29.

Each block is rivetted to the arm by an associated rivet lying on the centre line. In the case of the block 30 adjacent the pointed end 24, this is the rivet 23 that connects the shorter link 16 to the arm 13. In the case of the other block 30, it is a separate rivet 34. In addition, each block 30 is provided with an elongate fixing hole 35. The fixing holes 35 lie on the centre line 39.

The friction stay of Figures 1 to 5 is made of metal.

In use, the friction stay is for connecting a movable window leaf to a fixed window frame. The leaf and the frame are of metal. In an arrangement where the leaf and the frame are rectangular, two stays are used connected between respective opposite edges of the leaf and associated edges of the frame.

The base member 10 is fixed to the frame by fastenings passing through the holes 25. These fastenings may be screws.

Referring to Figure 3, the arm 13 is connected to an edge of the leaf 36 which is provided with a channel indicated generally at 37 formed as a so-called "Eurogroove". As seen in Figure 3, the channel 37 has a base 38 and spaced parallel side walls 39. Each side wall has a lip 40 projecting from the side wall parallel to the base 38 with a gap 41 between the adjacent edges of the lips 40.

The fitting of the arm 13 in this channel 37 will now be described with reference to Figures 3, 4 and 5. It will be appreciated that this fitting is conducted with the stay fully assembled and before the base member 10 is connected to the frame.

The stay is offered up to the channel 37 with the arm 13 extending along the channel but rotated about the centre line 29 by about 450 so that the second members 32 of the blocks 30 extend through the gap 41 with one lip 40 lying at the entrance to the two grooves 33. This is shown in Figure 3.

The arm 13 is then rotated about the centre line 29 so that the lip 40 enters the grooves 33 and the second members 32 slide beneath the lip 40. This is shown in Figure 4. As seen in Figure 5, when the rotation is complete, the lip 40 is within the grooves 33 and the second members 32 are beneath the lip 40. As also seen in this Figure, the width of the arm 13 is equal to the width of the channel 37 so that the arm 13 is partially received in the channel 37 with the under surface 28 of the arm 13 resting on the lips 40.

When in this position, screws can be inserted through the fixing holes 35 to connect the arm 13 to the leaf 36 in a required position along the channel 37.

The principal function of the blocks 30 is to provide increased security of attachment between the arm 13 and the leaf 36. In forced entry of a window, a lever is often inserted between the leaf and the frame to lever the leaf 36 out of the frame. This tends to apply a rotational force to the arm 13 about the centre line 29 which can pull the connecting screws passing through the fixing holes 35 out of the leaf. This rolling movement is resisted by engagement of the second members 32 of the projecting blocks 30 beneath the lip 40 of the Eurogroove channel 37.

In addition, the block 30 adjacent the pointed arm 24 has the benefits of providing a reinforcement to that end of the arm in the manner described in GB-A-2299372.

It will be appreciated that there need not be two blocks 30.

There could be one block 30 or three or more blocks 30. The block or blocks 30 need not be located as shown; they could be located at any position. The blocks 50 need not be Lshaped. They could be T-shaped, being inserted in the channel at one end.

It will also be appreciated that the arm 13 need not be connected to the channel 36 by rotation as described above with reference to Figures 3, 4 and 5. It could be slid into the channel 37 from one end.

The blocks 30 described above with reference to the drawings are shaped for engagement with a particular standard Eurogroove channel 37. It will be appreciated, however, that the arm 13 and the leaf 36 could have any suitable form of interengaging parts. This could be a projection on the arm 13 and a recess in the leaf 36 but it could be the opposite way round.

An alternative form of inter-engaging parts is shown in Figure 6. Although this Figure shows only the arm of a window stay, the remainder of the stay is as described above with reference to Figure 1. Parts common to Figures 1 and 6 are given the same reference numerals and are not described in detail.

Referring to Figure 6, the arm 43 of this Figure has the projecting blocks 30 replaced by mushroom-headed pins 44.

Each pin 44 has a stem 45 and a head 46. The two pins 44 project normally from the surface 28 of the arm 43 and the pins 44 lie on the centre line 29.

The leaf 36 has a wall 47 behind which is a cavity. The wall 47 is formed with two spaced keyhole-shaped apertures 48 each having a wider opening 49 through which the head 46 of a pin 44 can pass and a narrower portion 50 that is about the same width as a stem 45. The centres of the openings 49 are spaced by the same distance as the pins 44. The height of each stem 45 between the arm surface 28 and the head 46 is similar to the thickness of the wall 47.

The stay is connected to the leaf 36 by inserting the heads 46 of the pins 44 into respective openings 49 and then moving the stay relative to the leaf 36 to move the stems 45 along the narrower portions 50. This wedges the wall 47 between the heads 46 and the arm 43 to connect the arm 43 to the leaf 36.

As seen in Figure 6, the arm 43 may be provided with a hole 51 adjacent the pointed end 24 through which a screw 52 passes to fix the arm 43 to the leaf 36.

Other attachment devices may be used, such as a snap-fit arrangement.

Claims (23)

1. A friction stay comprising an elongate base member and an elongate arm connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a position in which the arm overlies the base member and a position in which the arm is spaced to one side of the base member and is angled relative to the base member, the arm including attachment means for inter-engagement with a formation on a mounting surface.

2. A friction stay according to claim 1 wherein the attachment means comprise a shaped member for insertion into and inter-engagement with a co-operating formation on said mounting surface.

3. A friction stay according to claim 1 or claim 2 wherein said shaped member has a cross-section that is of generally inverted L-shape, the cross-section lying in a plane normal to the length of the arm.

4. A friction stay according to claim 2 or claim 3 when dependent on claim 2 wherein said shaped member is one of two such shaped members included on said arm at spaced positions therealong.

5. A friction stay according to claim 1 or claim 2 wherein the attachment means comprise a mushroom-headed pin on the arm and the formation on the mounting surface comprises a cavity accessed through a slot having a widened portion through which the head is insertable into the cavity and a narrower portion for embracing the pin beneath the head as the pin is moved along the slot.

6. A friction stay according to claim 5 wherein said mushroom-headed pin is one of two such mushroom-headed pins arranged at spaced positions along the arm.

7. A friction stay according to any one of claims 1 to 6 wherein the.attachment means are formed separately from the remainder of the arm and are fixed thereto.

8. A friction stay substantially as hereinbefore described with reference to the accompanying drawings.

9. A closure comprising a leaf closable into and out of a frame, the leaf being connected to the frame by at least one friction stay comprising an elongate base member connected to the frame and an arm connected to the base member by a linkage that constrains the arm to movement in a plane parallel to the base member between a position in which the arm overlies the base member when the leaf is closed into the frame and a position in which the arm is spaced to one side of the base member and is angled relative to the base member which the leaf is opened out of the frame, the arm and the leaf including inter-engaging attachment means for connecting the arm to the leaf.

10. A closure according to claim 9 wherein the leaf includes a shaped recess and the arm includes a shaped projection engaging with the shaped recess to connect the arm to the leaf.

11. A closure according to claim 10 wherein the leaf includes a member extending along an edge of the leaf, the member comprising a channel extending therealong, the channel having a lip extending therealong and the shaped projection inter-engaging with said lip.

12. A closure according to claim 11 wherein said shaped recess forms a groove which receives said lip.

13. A closure according to claim 11 wherein the arm is formed from a strip of material with spaced parallel flat surfaces, the projection being mounted on one said surface and forming said groove with said surface.

14. A closure according to claim 13 wherein the projection comprises a first member extending away from said surface and having an edge remote from said surface and a second member extending from said edge generally parallel to said surface, to form said groove.

15. A closure according to any one of claims 10 to 14 wherein said projection is one of two such projections.

16. A closure according to any one of claims 11 to 14 wherein said channel is generally rectangular in cross-section with a base and parallel side walls, said lip being one of two such lips, each lip projecting from an associated side wall with the lips being in register and forming a gap therebetween.

17. A closure according to claim 16 wherein said arm is engaged with said channel by rotating the arm about the length thereof with the lip aligned with an entrance to said groove.

18. A closure according to claim 9 wherein the leaf includes an aperture and the arm includes a member insertable through said aperture and then engagable with the leaf by relative movement between the leaf and the arm.

19. A closure according to claim 18 wherein the member comprises a mushroom-headed pin and the aperture comprises a cavity accessed through an elongate slot with one end forming a wider opening through which the head is passable into the cavity, the slot having a narrower portion that embraces the pin behind the mushroom head on relative movement between the arm and the leaf.

20. A closure according to claim 19 wherein said pin is one of two such pins on the arm, the leaf including two cooperating cavities and slots.

21. A closure according to any one of claims 9 to 20 wherein the leaf is a window sash and the frame is a window frame.

22. A closure according to claim 22 wherein the sash and the frame are of metal.

23. A closure substantially as hereinbefore described with reference to the accompanying drawings.