GB2299372A

GB2299372A - Door or window stay

Info

Publication number: GB2299372A
Application number: GB9606574A
Authority: GB
Inventors: Clive James Smith
Original assignee: Euromond Ltd
Current assignee: Euromond Ltd
Priority date: 1995-03-29
Filing date: 1996-03-28
Publication date: 1996-10-02
Anticipated expiration: 2016-03-28
Also published as: GB9606574D0; GB2299372B; GB9506446D0

Abstract

In a friction stay for a door or window comprising a base 10 for connection to a frame and an arm 13 for connection to the leaf with a linkage 14, 16 controlling the movement of the arm relative to the base so that the arm moves in a plane generally parallel to the base between the closed position in which the arm overlies the base and open positions in which the arm is to one side of and angled relative to the base, a reinforcing member 28 is provided extending along the arm 13 with the connection 23 between the shorter link 16 and the arm also engaging the reinforcing member and a fixing hole 27 extending through the arm 13 and the member 28 at a position spaced from the connection. If the arm is forced away from the base during an attempt to force the leaf out of the frame, the strength of the stay to resist such a force is increased by the reinforcing member. Preferably the reinforcing member 28 comprises a metal or plastics plate and the connection 23 comprises a rivet. This arrangement is particularly useful where the arm is to fit into a "eurogroove" on a leaf.

Description

STAYS The invention relates to stays and more particularly to door or window stays for connecting a movable leaf to a fixed frame to allow the leaf to open out of and close into a fixed frame.

A stay of this type comprises an elongate base member for connection to the frame and an elongate arm for connection to the leaf. The arm is connected to the base member by a linkage that constrains the arm to move in a plane generally parallel to the plane of the base member between a position in which the arm overlies the base member (the position in which the leaf is closed into the frame) and a position in which the arm is to one side of the base member and at an angle to the base member (when the leaf is opened out of the frame). The links of the linkage are connected to the arm by solid rivets to provide pivotal connections between the links and the arms.

The arm and the base member are connected to the leaf and the frame respectively by a fixing, such as screws, passing through holes in the leaf of the arm respectively. In the case of the arm, these holes are located at positions spaced from the rivets.

Such stays have to be capable of resisting the significant forces that may be applied to the stay when an attempt is made to lever the leaf out of the frame. When this happens, the greatest forces are often those tending to separate the arm from the base member in a direction normal to the plane of the base member. At the arm, the spacing between the fixing holes and the rivets means that forces tending to separate the arm and the base member cause the links to apply forces to the arm which tend to bend the arm about an adjacent fixing point.

This decreases the resistance of the stay to such unauthorized entry.

In general, in a stay of this kind, there are two links connected between the base member and the arm; a shorter link and a longer link. One of the links may be connected to the base member via a slider. The bending moment is particularly acute with the shorter link since the short length of the link increases the forces transmitted from the link to the arm.

One proposal for overcoming this problem is to form the rivet holding the shorter link to the arm by a hollow rivet to provide a fixing hole through which a fixing such as a screw can pass to connect the arm to the leaf. In this case, there is no lever arm effect between the link rivet and the fixing.

However, the effect of this is to move the fixing hole forward (i.e. closer to an end of the arm) and, since that end of the arm is normally close to a corner of the leaf, it can be difficult under certain circumstances to engage a fixing such as a screw with the leaf at that position.

This is particularly the case where the leaf includes a socalled "eurogroove". This is a generally rectangular channel provided around the edge of the leaf and provided with a pair of opposed internal shoulders. The presence of such a groove can preclude the use of a fixing hole very close to the end of the arm adjacent the shorter link. Accordingly, it is necessary to use a fixing hole which is spaced from the rivet of the shorter link on a side of the rivet opposite the end of the arm. Thus, for such an arrangement, the lever arm effect still exists.

According to the invention, there is provided a door or window stay for connecting a movable leaf to a fixed frame and comprising an elongate base member for connection to the frame and an elongate arm for connection to the leaf, the arm being connected to the base member by a linkage that constrains the arm to move in a plane generally parallel to the plane of 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 at an angle thereto, the linkage including a longer link and a shorter link connected between the base member and the arm, a reinforcing member extending along the arm with the connection between the shorter link and the arm also engaging said reinforcing member, and a fixing hole extending through the arm and the reinforcing member at a position spaced from said connection.

By the use of a reinforcing member, the arm is strengthened against bending by the lever arm forces applied by the link as the arm is levered away from the base member.

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 from above of a window stay, Figure 2 is a perspective view of an end of an arm and a shorter link of the stay of Figure 1 showing a reinforcing support strip, and Figure 3 is a cross-section through a part of a leaf showing a "eurogroove" and the arm of Figure 2 fitted into the "eurogroove".

Turning first to Figure 1, the 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 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 has one end pivotally connected by a rivet 20 to the slider 19 and has the opposite end pivotally connected by a rivet 23 to a point on the arm 13 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 of the arm 13 in a manner described below. The arm 13 is provided with fixing holes 27; one fixing hole being adjacent the end of the arm 13 remote from the pointed end 14 and the other hole 27 being between the rivets 18,23.

The arm carries a reinforcing strip 28 best seen in Figures 1 and 3. The reinforcing strip 28 is a length of metal of rectangular cross section of generally the same thickness as the thickness of the arm 13 but of narrower width. The rivet 23 forming the connection between the shorter link 16 and the arm 13 extends through the reinforcing support strip 28 as does the hole 27 intermediate the rivets 18,23.

In use, the stay is for connecting a movable window leaf to a fixed window frame. 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 holes may be screws.

Referring to Figure 3, the arm is connected to an edge of the leaf 29 which is provided with a so-called "eurogroove".

As seen in Figure 3, this is formed by a channel 30 of generally rectangular cross section having a base 31 and side walls 32 provided with parallel shoulders 33.

As seen in Figure 3, the arm 13 fits into the channel and rests on the shoulders 33. The reinforcing support strip 28, which is narrower width than the arm 13, projects down into the bottom of the channel. A screw is passed through the holes 27 and into the base 31 of the channel to secure the arm 13 to the leaf.

The linkage 12 constrains the arm 13 to move relative to the base member 10 in a plane parallel to the base member 10. The linkage 13 moves between open positions and a closed position.

In the open positions, the arm 13 is spaced to one side of the base member 10 and extends at an angle to the base member 10, as shown in Figure 1. In the closed position (not shown), the arm overlies the base member and the pointed end 24 extends into the end cap 26. The function of the end cap 26 is to capture the pointed end of the arm 24, to guide the arm 13 to ensure that it moves into a position where it overlies the base member 10 and to hold the arm 13 in position once closed.

If unauthorized entry is attempted through the window, a common way of achieving such unauthorized entry is to insert an implement between the frame and the leaf to lever the leaf out of the frame. If this is done between two adjacent sides of the frame and the leaf carrying a stay, the effect is to try and separate the arm 13 from the base member 10; that is to say to move the arm in a direction generally normal to the plane of the base 10 (and possibly to move the arm 13 sideways as well).

When this happens, the longer and shorter links 14,16 apply a force to the arm 13 that tends to pull the arm 13 away from the leaf. In view of the presence of the fixings through the holes 27, this tends to apply a lever arm force to the arm 13 about the fixings and this can cause the arm 13 to flex so allowing unauthorized entry.

This is a particular problem with the length of the arm 13 connected to the shorter link 16. The short length of the link means that significant forces can be applied by the link 16 to the arm 13 at the rivet 23. However, the presence of the reinforcing support strip 28 resists such bending forces and so helps the stay to resist unauthorized entry.

Unauthorized entry can also apply lateral forces to the arm 13 i.e. forces in directions lying in planes parallel to the plane of the arm 13 (normal to the plane of a door or window to which the stay is fitted). These forces are resisted by the engagement of the side edges of the strip 28 with the walls of the channel 30. It will be appreciated that, in the absence of the strip, such forces would tend to rotate the arm 13 about the fixing through the hole 27.

The reinforcing strip 28 may extend to the pointed end 24 of the arm and have the same profile as the end 24.

It will be appreciated that a similar reinforcing support strip 28 may be provided between the rivet 18 on the longer link 14 and the hole 27 adjacent the end of the arm 13 opposite the pointed triangular end 24.

It will also be appreciated that a similar arrangement may be applied to stays other than stays of the kind described above with reference to the drawings. In particular, the arrangement may be applied to a stay of the kind described with reference to Figures 8 to 10 of GB-A-2247914.

A stay of this kind modified with a reinforcing support that extends to the pointed end 24, is shown in Figures 4, 5 and 6.

Referring-first to Figures 4 and 5, a reinforcing support block 35 is formed from nylon and has parallel side edges 36.

One end edge 37 is arcuately curved and the other end edge is formed, starting from one side edge 36, with an angled portion 38 followed by a generally axially extending portion 39, followed by a second angled portion 40, followed by a portion 41 generally normal to the centre line 42 of the block 35 and the second angled portion 40 may subtend an angle of 430 to the other side of the central line 42 to the first angled portion 38.

The support block 35 is formed with two fixing holes 43,44.

The first fixing hole 43 is a plain hole and is located towards the curved end edge 37 of the block 35. The second fixing hole 44 is provided with a counterbore 45 and is located towards the end of the block 35 with the angled portions 38,40.

As seen in Figure 5, the part of the block 35 on which the angled portions 38,40 are formed, is of lesser thickness than the remainder of the block 35. There is thus a step 46 between these parts.

The support block 35 is carried on a stay of the general type described and illustrated in Figures 8 to 10 of GB-A2247914. Many parts of this stay are the same as the stay shown in Figure 1 and parts common to the stay of Figure 1 and the stay of Figure 6 will be given the same reference numerals and will not be described in detail.

The support block 35 overlies the pointed end 24 of the arm 13. This end 24 of the arm is shaped to match the shaped end of the support block 35. The flat surface of the support block 35 contacts the arm 13 with the stepped surface exposed.

The support block 35 is connected to the arm 13 by a solid rivet 51 which passes through a hole at an end of the shorter link 16, a hole in the arm 13 and the second fixing hole 44 in the support block 35 with the head of the rivet 51 being received in the counterbore 45. The rivet 51 thus provides a pivotal connection between the arm 13 and the shorter link 15.

The first hole 43 in the support block 35 is in register with a hole 52 in the arm 13 to provide a hole for a fixing screw to connect the arm 13 to a leaf. The width of the support block 35 is the same as the width of the arm 13.

In the stay of Figure 6, the base member 10 carries an end cap 47 which is generally L-shaped. One limb of the end cap 47 is received in the end of the base member 10. A hole (not shown) in the limb registers with a hole (not shown) in the base member 10 to allow a fixing screw to pass through the holes and into a frame.

The other limb of the end cap 47 is provided with an aperture 48 which is shaped to receive the end 24 of the arm 13 and the overlying end of the support block 35. The aperture 48 includes an upper wall 49 that overlies the ends of the arm 13 and the support block 35. AS seen in Figure 6, the front edge 50 of the aperture 48 engages the step 46 on the support block 35 to position the arm 13 relative to the base member 10.

This limb also includes a hole through which a screw can be passed to connect the end cap 47 to a frame. The connection need not be via a screw; any suitable form of connection may be used.

In such a stay, forces on the arm 13 tending to separate the arm 13 from the base member 10 (the kind of forces that might be applied on forced entry of a window carrying the stay) are resisted by engagement of the end of the arm 13 in the end cap 47. Such resistance generates a bending movement about the end of the arm 13 and this is resisted by the additional strength provided by the support block 35. The rivet 51 and the first hole 43 are located as close as possible to the pointed end to minimise the lever arm length on such forced separation.

Of course, the support block 35 need not be of a plastics material; it could be of metal.

Claims

1. A door or window stay for connecting a movable leaf to a fixed frame and comprising an elongate base member for connection to the frame and an elongate arm for connection to the leaf, the arm being connected to the base member by a linkage that constrains the arm to move in a plane generally parallel to the plane of 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 at an angle thereto, the linkage including a longer link and a shorter link connected between the base member and the arm, a reinforcing member extending along the arm, with the connection between the shorter link and the arm also engaging said reinforcing member and a fixing hole extending through the arm and the reinforcing member at a position spaced from said connection.

2. A stay according to claim 1 wherein said reinforcement comprises a plate, the link connection and the fixing hole extending through both the arm and the reinforcement plate.

3. A stay according to claim 1 or claim 2 wherein the link connection comprises a rivet.

4. A stay according to any one of claims 1 to 3 wherein the support is of nylon.

5. A stay according to any one of claims 1 to 4 wherein the arm has a shaped end adjacent said connection, the reinforcement having a correspondingly shaped end in register with the shaped end of the arm.

6. A stay according to claim 5 and further comprising a generally fl-shaped end cap, one limb of the end cap engaging the base member and the other limb of the base member including means for engaging the end cap to an adjacent frame, said other limb also including a recess for receiving the pointed ends of the arm and the support when the arm is closed over the base member1 the recess engaging the pointed ends should the arm be forced away from the base member.

7. A stay substantially as hereinbefore described with reference to Figures 1 to 3 or to Figures 4 to 6 of the accompanying drawings.