GB2306564A

GB2306564A - Stay with Releasable Catch

Info

Publication number: GB2306564A
Application number: GB9521953A
Authority: GB
Inventors: Clive James Smith; Edmund Arthur Dubois; John Stuart Bell
Original assignee: REGENCY INTERNATIONAL PLC; Euromond Ltd
Current assignee: REGENCY INTERNATIONAL PLC; Euromond Ltd
Priority date: 1995-10-27
Filing date: 1995-10-27
Publication date: 1997-05-07
Anticipated expiration: 2015-10-27
Also published as: GB9521953D0; GB2334548A; GB2306564B; GB9913895D0; GB2334548B

Abstract

A friction stay for a window has a channel member carrying slider(s) where one slider has a restrictor device which allows only limited opening, but is releasable to permit further opening of the window. The slider includes a latch (30) engaging a lug (34) on the channel member for releasably connecting the slider to the channel member with some play. An operating lever member (40) is provided on the lug (34) to release the latch by pressing on arm (42) and a safety block (41), with tab (52) to facilitate its removal, is provided to prevent accidental operation of the lever member.

Description

STAYS The invention relates to friction stays.

Friction stays are used in pairs to support a door or window leaf in a door or window frame. A typical stay comprises a base member for connection to the frame and an arm for connection to the leaf, with a linkage extending between the arm and the base member to control movement of the arm between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and angled relative thereto. The movement of the arm is in a plane generally parallel to the plane of the base member and normal to the plane of the frame.

One form of linkage includes a shorter link connected between the arm and the base member and a longer link connected between the arm and the base member. The connection between the longer arm and the base member is by way of a slider which is held by the base member for sliding movement along the length of the base member as the arm moves between the open and closed positions.

It has been proposed (see, for example, GB-A-2273526) to include a latching element on the slider capable of locking the slider to the base member after limited opening movement of the arm. This is a safety feature to prevent people falling accidentally through the frame aperture. The latch can be released to allow full opening in the event of an emergency.

According to a first aspect of the invention, there is provided a friction stay comprising a base member for connection to a door or window frame and an arm for connection to an associated door or window leaf to control the opening and closing of the leaf out of and into the frame, the arm being connected to the base member by a linkage including a shorter link connected between the arm and the base member and a longer link connected between the arm and a slider carried by the base member for sliding movement therealong, the linkage constraining the arm to movement in a plane parallel to the plane of the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and angled relative thereto, the slider having a restricted device associated therewith which, when operative, allows only limited movement of the arm towards the open position but is releasable to omit further movement of the arm towards the open position, the restrictor device being released by an actuating member covered by a removable cover that normally prevents access to said actuating member.

According to a second aspect of the invention, there is provided a friction stay comprising a base member for connection to a door or windcw frame and an arm for connection between an associated door or window leaf to control the opening and closing of the leaf into and out of the frame, the arm being connected to the base member by a linkage including a shorter link connected between the arm and the base member and a longer link connected between the arm and a slider carried by the base member for sliding movement therealong, the linkage constraining the arm to movement in a plane parallel to the plane of the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and angled relative thereto, the slider having a restrictor device associated therewith which, when operative, allows only limited movement of the arm towards the open position but is releasable to permit further movement of the arm towards the open position, the restrictor device being released by an actuating member operated by an operating member connected to the base member.

The following is a more detailed description of some embodiments of the invention, by way of example, reference being made to the accompanying drawings in which: Figure 1 is a plan view from above of a stay not in accordance with the invention with an arm of the stay in a fully open position relative to a base member of the stay and showing a latching member disengaged from a stop on the base member, Figure 2 is a similar view to Figure 1, but showing the whole of the arm overlying the base member of the stay, Figure 3 is a side elevation of the stay of Figures 1 and 2 in the disposition shown in Figure 7, Figure 4 is a section on the line IX-IX of Figure 3 and Figure 5 is a similar view to Figure 4 but showing the latching member disengaged from the stop on the base member, Figure 6 is a side elevation and a plan view from above of a part of the stay of Figures 1 to 5 modified in accordance with the invention and including an operating device and a removable cover, Figure 7 is a side elevation of the operating device of Figure 6, Figure 8 is a partial plan view and a partial side elevation of a lug of the stay of Figures 1 to 5 modified to receive the operating device of Figure 6, Figure 9 is a side elevation and a plan view of the removable cover of Figures 6 and 7, Figure 10 is a side elevation of a second form of the actuating member, and Figure 11 is a similar view to Figure 9 but showing the second form of the actuating member in operation.

Referring first to Figures 1 to 5, the stay comprises a base member 10 connected to an arm 11 by a linkage comprising a shorter link 12, an intermediate link 13 and a longer link 14.

The base member 10 has a pair of guides 23 extending along respective side edges of the member 10 and formed by two side walls upstanding from respective side edges of the base member 10 and inwardly directed flanges 24 extending parallel to the base member 10 from the upper ends of the side walls.

The shorter link 12 has one end connected to a first slider 25 carried by the base member 10 for rectilinear sliding movement guided by the guides 23. The connection is to a pivot point 15 on the first slider 25. The opposite end of the shorter link 12 is pivotally connected adjacent an end of the arm 12 at a pivot point 16. The longer arm 14 has one end pivotally connected to a second slider 17 carried by the base member 10 for rectilinear sliding movement along the base member 10 guided by the guides 23. The opposite end of the longer arm 14 is pivotally connected to the arm 11 at a pivot point 18 intermediate the ends of the arm 11.

The intermediate link 13 is connected between a pivot point 19 intermediate the ends of the longer arm 14 and a pivot point 20 on the first slider 25 adjacent the pivot point 15 of the shorter arm 12.

The linkage thus constrains the arm to pivotal and translational movement relative to the base member 10 between the position shown in Figures 2 and 3 in which the arm 11 overlies the base member 10 and the position shown in Figure 1 where the arm extends almost at right angles to the length of the base member 10 to one side of the base member 10.

The second slider 17 carries a latch 30. The latch 30 is made from a resilient material such as spring steel and is attached to the second slider 17 at one end. The latch 30 extends from the second slider 17 along the length of the base member 10 towards the end of the base member 10. At its end remote from the slider 17, the latch 30 is provided with a tab 31 that curves away from the base member 10 and, intermediate its ends, the latch 30 has a widened portion 32 provided with a central hole 33.

As seen in Figures 4 and 5 in particular, the attachment of the latch 30 to the second slider 17 is such that the widened portion 32 lines in a plane which is parallel to but spaced from the flanges 27 forming the guides of the base member 10.

This spacing is in a direction away from the base member 10 so that the latch 30 lies above the base member 10 and above the flanges 27.

The base member 10 carries at the end adjacent the latch 30, a lug 34 which fits between, and extends beyond, the ends of the flanges 27, as best seen in Figures 1, 4 and 5. The lug 34 has a base 35 which is fixed to the base member 10 by rivets 36 and has also an upper surface formed with two mutually inclined surfaces 37,38.

A first inclined surface 37 lies in a plane which is normal to a plane which includes the direction of movement of the first slider 17 and which extends normal to the plane of the base member 10. This plane of the surface 37 is also inclined relative to the direction and movement of the second slider 17 but at a comparatively shallow angle. The inclination is such as to tilt the inclined surface 37 towards a second slider 17.

The second inclined surface 38 shares a common end edge 40 with the first inclined surface 37 and is at the end of the surface 37 remote from the second slider 17. The second inclined surface 38 extends downwardly towards the body 21 and lies in a plane normal to the plane of the hole 33. Thus, in section, as seen in Figures 4 and 5, the surfaces 37,38 define respectively the hypotenuse and one side of an imaginary right-angled triangle lying in a plane including the direction and movement of the slider 17 and extending normal to the direction of the hole.

When the arm 11 is in the closed position shown in Figures 3, 4 and 5, the inclined surfaces 37,38 of the lug 34 project through the hole 33 of the latch 30.

In use, two stays of the kind described above with reference to Figures 1 to 5 are connected between respective opposite horizontal side edges of the window leaf and a fixed frame with the base member 10 on the frame and the arm 11 on the leaf. Each stay is connected so that the end of the base member 10 opposite the latch 30 is adjacent a corner of the frame and the leaf, with the latch 30 thus being spaced from the corner for ease of access and operation.

The stays can be operated in three modes. In a first mode, the first slider 25 is locked to the base member 10 and the arm 11 is permitted limited opening movement from the position shown in Figures 7 and 8 by lost motion between the hole 33 and the lug 34. When the surface 38 on the lug 34 engages the end of the hole 33, no further opening movement is possible.

This prevents anyone falling out of the window by accident.

If the tab 31 is then lifted to disengage the hole 33 from the lug 34, the arm 11 and the associated leaf can be swung further out of the frame with the second slider 17 sliding up the base member 10 guided by the guides 23. This will continue until the second slider 17 hits a stop 24 (Figures 4 and 5) provided on the base member 10. When in this position, the leaf and arm 11 are open to their maximum possible extent as shown in Figure 1. This gives the maximum aperture in the frame for emergency exit.

A third mode of operation is with the latch 30 engaged with the lug 34 and the first slider 25 released. In this case, opening the leaf out of the frame causes the first slider 25 to slide along the base member 10 towards the second slider.

This positions the leaf between the ends of the base member 10 so that there is a substantial gap between the inner edge of the leaf and the adjacent edge of the frame. This allows both sides of the leaf to be accessed for cleaning. This mode is optional; the first slider 25 may be omitted and the associated links 12,13 connected directly to the base member 10.

Stays of this general type are known and the present invention does not relate to the above described features of the stay but to modifications to this stay now to be described.

Referring first to Figures 6 to 9, the first modification includes a cranked lever 40 which pivots on the lug 34 to lift the latch 30. The lever is covered by a safety block 41.

The lever 40, seen in Figure 7, has a first limb 42 connected by a double crank 43 to a second limb 44. A pair of trunnions 45 project from the lever 40 at opposite sides of the junction between the double crank 43 and the second limb 44. The end of the second limb 44 is provided with a projection 46.

Referring next to Figure 8, the end of the lug 34 is provided with a projection 47 formed with a rectangular hole 48. The portions of the projection 47 forming the longer side edges of the rectangular hole 48 are provided, at the end of the projection 47 remote from the base member 10, with registering downwardly facing semi-circular cut-outs 49.

As seen in Figure 6, the second limb 44 sits in the rectangular hole 48 with the trunnions 45 received in the cutouts 49. The projection 47 engages the under surface of the tab 31 when the tab 31 is in engagement with the lug 34.

Thus, as seen in Figure 6, by pressing down on the first limb 42, the second limb 44 is raised to raise the tab 31 to disengage the latch 30 from the lug 34. The leaf can then be opened to its widest extent for emergency egress.

The safety block 41 is shown in Figure 9. It comprises a generally rectangular block 51 and an elongate break tab 52 connected to the block 51 along one edge of the block 51 and extending over an upper surface 53 of the block and from an opposite side of the block 51. This spacing forms a slot 54 between the brake tab 52 and the upper surface 53. The end of the brake tab 52 remote from the block 51 is provided with a hole 55.

In use, as seen in Figure 6, the end of the first limb 42 fits into the slot 54 between the break tab 52 and the block 51.

The size of the block 51 is such that the block 51 bears against the adjacent frame surface (not shown). The break tab 52 overlies the first limb 42 and extends over the tab 31.

The break tab 52 thus covers both of the first limb 42 of the lever 40 and the tab 31 of the latch. This prevents accidental operation of these parts. However, the break tab 52 can be pulled away in an emergency to reveal the first limb 42 which can then be operated to release the latch and allow maximum opening of the leaf for emergency egress. The break tab 52 may be provided with a break point to ease its removal.

An alternative arrangement is shown in Figures 10 and 11. In this case the end of the lug 34 is formed with a pair of rods 60 that extend in directions transverse to the length of the base member 10. This is engaged by a double cranked lever arm 61. As seen in Figure 10, the rods are arranged so that they are beneath the end of the tab 31. Thus, when the lever arm 61 is raised, the tab is disengaged from the lug 34 to allow maximum opening of the leaf for emergency egress.

Claims

1. A friction stay comprising a base member for connection to a door or window frame and an arm for connection to an associated door or window leaf to control the opening and closing of the leaf out of and into the frame, the arm being connected to the base member by a linkage including a shorter link connected between the arm and the base member and a longer link connected between the arm and a slider carried by the base member for sliding movement therealong, the linkage constraining the arm to movement in a plane parallel to the plane of the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and angled relative thereto, the slider having a restrictor device associated therewith which, when operative, allows only limited movement of the arm towards the open position but is releasable to omit further movement of the arm towards the open position, the restrictor device being released by operation of an actuating member covered by a removable cover that normally prevents access to said actuating member.

2. A friction stay according to claim 1 wherein said actuating device is operated by an operating member mounted on the base member.

3. A friction stay comprising a base member for connection to a door or window frame and an arm for connection between an associated door or window leaf to control the opening and closing of the leaf into and out of the frame, the arm being connected to the base member by a linkage including a shorter link connected between the arm and the base member and a longer link connected between the arm and a slider carried by the base member for sliding movement therealong, the linkage constraining the arm to movement in a plane parallel to the plane of the base member between a closed position in which the arm overlies the base member and an open position in which the arm is to one side of the base member and angled relative thereto, the slider having a restrictor device associated therewith which, when operative, allows only limited movement of the arm towards the open position but is releasable to permit further movement of the arm towards the open position, the restrictor device being released by operation of an actuating member operated by an operating member connected to the base member.

4. A friction stay according to claim 3 wherein the actuating member is covered by a removable cover that normally prevents access to said actuating member.

5. A friction stay according to any one of claims 2 to 4 wherein the actuating member is pivotally mounted on the base member.

6. A friction stay according to any one of claims 2 to 5 wherein the base member comprises a channel member which receives and guides the slider and an extension member projecting from one end of the base member, the actuating member being mounted on said extension member.

7. A friction stay according to claim 6 wherein said actuating member comprises a lever having first and second ends pivotally mounted on the extension member with said pivotal mounting intermediate the ends of the lever, downward pressure on the first end of the lever causing the second end of the lever to release the restrictor device.

8. A friction stay according to claim 7 wherein the lever arm includes a pair of trunnions intermediate the first and second ends by which the lever is pivotally mounted on the extension piece, the portion lever to said first end lying in a plane parallel to but spaced from the portion of the lever to the second end, said first-mentioned portion being connected to the other portion by a double crank.

9. A friction stay according to claim 7 wherein said actuating member comprises a lever having first and second ends, the second end being pivotally connected to said extension member and the first end including a double crank, the lever being pivotable from said first end from a depressed position to a raised position to release the restrictor device.

10. A friction stay according to any one of claims 6 to 9 wherein the lever is pivotable about an axis lying in a plane parallel to the plane of the base member and extending in a direction normal to the length of the base member.

11. A friction stay according to any of claims 7 to 10 when dependent on claim 1 or claim 4 wherein the cover includes a portion that encloses the first end of the lever to prevent operation of the lever, said portion being removable to allow access to said first end.

12. A friction stay according to claim 11 wherein said portion is formed by a block and a break tab that form therebetween a slot for receiving said first end of the lever, the block, in use, being located between said cranked first end and an adjacent surface and the break tab being removable.

13. A friction stay according to any one of claims 1 to 12 wherein the restrictor device includes a latch which is movable in a direction normal to the plane of the base member between a position in which the latch is closer to the base member and in which the latch allows only said limited opening movement of the arm towards the open position and a position in which the latch is further from the base member to permit said further movement of the arm, the actuating member, on operation, moving said latch between said closer and further positions.

14. A friction stay according to claim 14 wherein said latch is mounted on said slider and, in said closer position, engages a part on the base member to limit the movement of the arm.