GB2383376A

GB2383376A - Friction Stay

Info

Publication number: GB2383376A
Application number: GB0229050A
Authority: GB
Inventors: Donal Ring
Original assignee: Jurras Ltd
Current assignee: Jurras Ltd
Priority date: 2001-12-19
Filing date: 2002-12-13
Publication date: 2003-06-25
Also published as: GB0229050D0; IE20011085A1

Abstract

A friction stay includes a guide channel 10, first and second friction slides 14, 16 slidable along the channel 10 and a lock arrangement 28 co-operable with both first and second friction slides 14, 16 to restrict their movement. The lock arrangement has a housing 30, which is fixed to the window frame next to the channel 10, containing a slidable link 36 having a projection 38 for restraining movement of the first slide 14. The link 36 also slidably co-operates with a lock member 50 for restricting movement of the second slide 16. To move the window to an easy clean position, the link 36 is pivoted up manually to release the projection 38 from the first slide 14 to allow it to slide whilst the second slide 16 is restrained. If the window is to be opened to its egress position, then the window is initially opened during which the slide 14 slides link 36 within its housing 30 to release locking member 50 thereby allowing the second slide 16 to move.

Description

FRICTION STAY This invention relates to a friction stay primarily intended for use with the moveable vent of a window.

A type of friction stay has been developed in which, as the vent is moved towards its open condition, the'"hinged"side of the vent slides away from the associated side of the window frame. As a result, when the vent is fully open, both sides of the glazed panel thereof are accessible from within a building in which the window is fitted, allowing relatively easy cleaning of both sides of the glazed panel. This is particularly beneficial for windows above ground level.

One disadvantage of this type of friction stay is that the maximum open width of the window is reduced. As a result, the window may be insufficiently large to act as a fire or emergency escape.

Several friction stays have been designed in which, during normal operation, the stay operates to allow easy cleaning but upon applying a relatively large side load to the open window, the open window can slide sideways relative to the frame to increase the size of the opening to a size sufficient to allow the opening to act as an emergency exit. Other designs are known in which by operation of a

lock arrangement during opening, the vent can be opened into either an easy clean or an egress position.

It is an object of the invention to provide a friction stay of relatively simple and convenient form in which a vent carried by the stay can be opened either into an egress or an easy clean position.

According to the present invention there is provided a friction stay comprising guide channel, first and second friction slides slidable within the guide channel, a mounting arm, a linkage mechanism connecting the mounting arm to the first and second friction slides, and a lock arrangement controlling movement of the first and second friction slides, the lock arrangement being co-operable with both the first and second friction slides to restrict sliding movement thereof.

The lock arrangement preferably comprises a link member co-operable with the first friction slide, the link member being coupled to a lock member co-operable with the second friction slide. Preferably, sliding movement of the link member causes retraction of the lock member to allow sliding movement of the second friction slide whilst the first friction slide is restrained against sliding movement.

Pivotal movement of the link member conveniently allows the first friction slide

to move whilst the lock member retains the second friction slide against movement.

The friction stay may be arranged such that, when the first slide is held against movement the vent can be opened to an egress position, and when the second slide is held against movement the vent can be opened to an easy clean position.

The invention will further be described, by way of example, with reference to the accompanying drawings, in which: Figure I is a perspective view of part of a friction stay in accordance with an embodiment of the invention with the stay in a fully open, egress condition; Figure 2 is a view similar to Figure 1 but with the stay in a fully open, easy clean condition ; Figure 3 is a perspective view of the stay (with some parts removed) in a closed condition; and Figures 4 to 16 are diagrammatic views illustrating the operation of the stay.

Referring to Figures 1 to 3, the friction stay comprises a guide channel 10 secured, in use, to a fixed part of a window frame. Although a number of fixing techniques could be used, the channel 10 is conveniently secured in position using screws which extend through openings 12 formed in the channel 10.

Slidably mounted to the channel 10 are first and second friction slides 14,16. A linkage mechanism consisting of linkage arms 18,20, 22 is pivotally mounted

upon the frictions slides 14, 16, the linkage mechanism being connected to a mounting arm 24. In use, the mounting arm 24 is secured to a part of the frame of a moveable vent, conveniently using screws which extend through openings 26 formed in the mounting arm 24.

The linkage mechanism is designed such that, as the friction slides 14,16 move relative to one another from a position in which they are spaced apart to a

position in which they are close or adjacent to one another, the mounting arm 24 i 9 is moved from a closed position in which it overlies the channel 10 to an open position in which it lies generally perpendicular to the channel 10. As shown in Figures 1 and 2 there are two such open positions. The open position shown in Figure 1 is achieved when the first slide 14 is held against movement and the second slide 16 slides towards the first slide 14. In this open position the vent is held adjacent to the"hinge"side of the window frame, ensuring that the unobstructed window opening is sufficiently large to allow the use thereof as an

emergency exit. The open position shown in Figure 2 is achieved by holding the second friction slide 16 against movement, the first friction slide 14 moving towards the second slide 16. In this position both sides of a glazed panel mounted in a vent carried by the friction stay are accessible from within the building, thereby allowing cleaning to take place.

In accordance with the invention, a lock arrangement 28 is provided to control which of the friction slides, 14,16 is permitted to move at any given time, thereby controlling to which of the open positions the vent will move. The lock arrangement 28 comprises a housing 30 mounted adjacent the channel 10.

Although the lock arrangement 28 could be secured to the channel 10, in a practical embodiment it is simply located next to the channel 10 and the channel 10 and housing 30 are secured to the window frame. In order to ensure correct location of the housing 30 relative to the channel 10, the housing 30 is provided with location projections 32 receivable within corresponding openings provided in the channel 10. The housing 30 may be closed, but as it is intended to be secured to the window frame, in use, the housing 30 is conveniently open on the side thereof which, in use, faces the window frame.

The housing 30 defines an axially extending channel 34 within which a link member 36 extends. The link member 36 is slidable within the channel 34, the

channel 34 further being shaped so as to permit a limited amount of pivotal movement of the link member 36. The link member 36 includes a projection 38 extending perpendicularly to the main part thereof, the projection 38 extending, as shown in Figure 4, through an opening 40 formed in the housing 30, a corresponding opening 42 formed in the guide channel 10 and being co-operable with a recess 44 formed in the first slide 14.

The link member 36 further includes an angled slot 46 within which a projection 48 formed on a lock member 50 is received such that longitudinal sliding movement of the link member 36 causes sliding movement of the lock member 50 to occur. The lock member 50 is slidable between an operative position in which it extends through an opening formed in the channel 10 and is co operable with a recess 52 formed on the second slide 16 and a retracted position in which such co operation does not occur.

The link member 36 and channel 34 are formed, respectively, with a recess 54 and projection 56 designed such that pivotal movement of the link member 36 can only occur when the link member 36 occupies a predetermined axial position.

One end of the link member 36 is provided with a latch formation 58 co- operable with a pivotable latch member 60 pivotable about a pivot pin. The latch member 60 includes an integral resilient spring region 62 urging the latch member 60 in an anti-clockwise direction (in the orientation illustrated in Figures 4 to 16). The latch member 60 further includes a tooth 64 co-operable with the second slide 16 with the result that the position occupied by the latch member 60 depends upon the position of the second slide 14.

As shown in Figure 3, the housing 30 includes an opening 68 through which the link member 36 is accessible, and a second opening 70 aligned with a recess 72 formed in the link member 36.

Typically two such stays are used to mount a vent to a window frame, the stays being positioned on opposing sides of the vent, and the operation of the to stays is substantially identical.

The operation of the friction stays will now be described with reference to Figures 4 to 16. Figure 4 illustrates one of the friction stays (with the linkage mechanism and mounting arm 24 removed for clarity) in its closed position.

When it is desired to open the vent to its easy clean open position, the vent is opened slightly thereby allowing access to the housing 30. An operator then

moves the link member 36 pivotally by placing his finger into the opening 68. Although not shown, such movement is against a resilient bias conveniently achieved by locating a plate spring behind the link member in the space 74 shown in Figure 4. Once moved to this position, the link member 36 is conveniently held in this position by introducing, for example, an end of a pen or pencil through the opening 70 into the recess 72. This position of the link member 36 is shown in Figure 5 from which it will be appreciated that the link member 36 no longer co-operates with the first slide 14 allowing sliding movement thereof to occur, and that the lock member 50 prevents movement of the second slide 16.

Continued movement of the vent causes the first slide to move to the positions shown in Figures 6 and 7, in turn, Figure 7 showing the friction stay in its fully open easy clean position.

Returning the vent to its closed position causes the first slide 14 to return to its original position. Removal of the pen or pencil allows the link member 36 to return to its original position under the action of its spring biasing. If the pen or pencil is removed before the vent is closed then the position shown in Figure 8 will be reached in which the projection 38 obstructs the movement of the first slide 14. In order to allow movement of the slide 14 to continue, a ramped

region is formed on the first slide 14 over which the projection 38 rides forcing the projection into the housing 30 to allow the first slide 14 to pass. The continued movement of the first slide 14 will result in the stay returning to its full closed position as shown in Figure 9.

If, rather than open to its easy clean position, it is desired to open the window to its egress position, the vent is opened. The initial movement of the vent causes the first slide 14 to move from the position shown in Figure 10 (closed) to that shown in Figure 11. As the lock member 50 is holding the second slide 16 against movement, further opening of the vent still causes movement of the first slide 14, causing the link member 36 to slide within the housing 30.

The sliding movement of the link member 36 causes the lock member 50 to retract thereby allowing the second slide 16 to move. As shown in Figures 12 to 14, further movement of the vent causes the second slide 16 to move towards the first slide 14 resulting in the vent being opened into its egress position.

As the second slide 16 moves away from the position shown in Figure 12, the latch member 60 pivots to the position shown in Figure 13 in which it engages the link member 36, holding the link member 36 against sliding movement. This is desirable as, if such movement were to occur, the lock member 50 could be

returned to its original position, preventing the subsequent return of the second slide 16 to its closed position.

Figures 15 and 16 show the return of the friction stay to its closed position, Figure 15 illustrating the disengagement of the latch and Figure 16 illustrating the second slide 16 in its closed position. From the position shown in Figure 16, fully closing the vent causes the first slide 14 to move to the right, the final part of the movement drawing the link member 36 to its original position returning the lock member 50 to the position shown in Figure 4.

It will be appreciated that throughout the movement of the friction stay to its egress fully open position, movement of the first slide 14 is restrained or restricted by the link member 36. Further, once sliding movement of the link member 36 has commenced. the projection 56 co-operates with the link member 36 to prevent pivotal movement thereof occurring thereby ensuring that the first slide 14 cannot be released for sliding movement.

The design of the lock arrangement is such that the default operation of the friction stay is its egress mode thus, in the event of a fire, an operator simply needs to open the window, no adjustment of the lock arrangement being necessary.

Claims

1. A friction stay comprising guide channel, first and second friction slides slidable within the guide channel, a mounting arm, a linkage mechanism connecting the mounting arm to the first and second friction slides, and a lock arrangement controlling movement of the first and second friction slides, the lock arrangement being co-operable with both the first and second friction slides to restrict sliding movement thereof.

2. A stay according to Claim 1, wherein the lock arrangement comprises a link member co-operable with the first friction slide, the link member being coupled to a lock member co-operable with the second friction slide.

3. A stay according to Claim 2, wherein sliding movement of the link member causes retraction of the lock member to allow sliding movement of the second friction slide whilst the first friction slide is restrained against sliding movement.

4. A stay according to Claim 2 or Claim 3, wherein pivotal movement of the link member allows the first friction slide to move whilst the lock member retains the second friction slide against movement.

5. A stay according to any one of the preceding claims, wherein the friction stay is arranged such that, when the first slide is held against movement the vent can be opened to an egress position, and when the second slide is held against movement the vent can be opened to an easy clean position.

6. A lock arrangement for use in a friction stay according to any one of the preceding claims.