EP1689961A1

EP1689961A1 - Window stay arrangement

Info

Publication number: EP1689961A1
Application number: EP04798603A
Authority: EP
Inventors: Terence James 6 The Benyon Centre DOLMAN
Original assignee: Trojan Hardware and Design Ltd
Current assignee: Trojan Hardware and Design Ltd
Priority date: 2003-11-19
Filing date: 2004-11-19
Publication date: 2006-08-16
Also published as: GB2424038A; GB2424038B; WO2005052295A1; GB0326908D0; GB0611786D0

Abstract

A stay arrangement (10) has a sash arm (12) and a frame track (18). Two carriages (20, 20A) carry the stay arrangement, by pivots (28, 34). Both carriages (20, 22) are able to move along the track (18) but are constrained by a locking arrangement controlling the carriage (22), and a friction arrangement controlling the carriage (20). With the locking arrangement engaged, the window can open normally, to a fully open position for emergency egress. With the locking arrangement released, the carriage (22) can move from the end of the track (18) (as shown) to allow access to the outside face of the window, for cleaning. The pivot arrangements shown, and particularly the use of a slot (62), allow the motion of the sash to be modified, for example to ensure that seals are not trapped, or to accommodate different sash or frame profiles.

Description

Window Stay Arrangement

The present invention relates to window stay arrangements. Window sashes, whether side opening or top opening, are commonly mounted in a window frame by means of a window stay arrangement which allows the sash to open and close. The window stay arrangement is subject to a number of design constraints, some of which are conflicting. For example, the window should be able to open as widely as possible, to allow emergency egress, but this usually limits access to the outer surface of the sash, for cleaning purposes. Some arrangements for resolving these conflicting constraints have been found difficult or dangerous to operate in practice, or may hinder adequate security. The present invention provides a window stay arrangement comprising:- a track member for attachment to a window frame; a sash member for attachment to a sash to be mounted for opening and closing in the frame; first and second carriage members which, in use, are able to move along the track member; a pivot linkage connecting the track member and the sash member and including first and second arms pivotally connected to the sash and to a respective carriage member; a releasable locking arrangement operable to lock at least one of the carriage members against movement along the track member; and release means operable to release the locking arrangement when the sash is moved to a predetermined position.

The predetermined position is preferably the fully open position.

The locking arrangement is preferably operable to lock only one of the carriage members. The other carriage member may be associated with a restraining arrangement which resists movement of the restrained carriage from an initial position, the restraint being overcome when the said one carriage member is locked, but not when the locking arrangement is released, whereby the restrained carriage will move along the track member when the sash is moved with the locking arrangement engaged, and the said one carriage will move from a corresponding initial position when the sash is moved with the locking arrangement disengaged.

The said initial positions preferably correspond with the sash being closed in the frame. The locking arrangement preferably re-engages as the said one carriage returns to the initial position. The locking arrangement may comprise a sprung member which blocks movement of the said one carriage member when in an advanced position, and is retractable by action of the release means to release the said one carriage member. The release means may comprise a shuttle member movable to a position at which the shuttle member causes the release means to release the locked carriage. In use, the carriage members may engage the shuttle member to move the shuttle member to release the locked carriage. The shuttle is preferably positioned between the carriage members. When the locking member is engaged, the shuttle member is preferably moved by the unlocked carriage member as the unlocked carriage member approaches the locked carriage member. The shuttle member may reach the locking arrangement, to release the locking arrangement, only when the sash is moved substantially to its fully open position. Movement of the lockable carriage member, when the locking arrangement is released, preferably moves the shuttle member away from the locking arrangement, allowing the locking arrangement to re-engage. The shuttle member may be constrained to a range of positions relative to the lockable carriage member.

In a second aspect, the invention provides a window stay arrangement comprising:- a frame member for attachment to a window frame; a sash member for attachment to a sash to be mounted for opening and closing in the frame; first and second intermediate members pivotally connected to the frame member and to the sash member; the second intermediate member being pivotally connected to the first intermediate member at a position between the pivotal connections of the first intermediate member to the frame member and the sash member; . the sash member being pivotally connected to the second member at a position between the pivotal connections of the second intermediate member to the frame member and the first intermediate member; the position of the pivotal connection between the frame member and one of the intermediate members being movable relative to the frame member; and the position of the pivotal connection between the sash member and the second intermediate member being movable relative to the second intermediate member, as the sash member moves relative to the frame member.

Preferably the pivotal connection between the sash member and the second intermediate member is constrained to move along a curved path relative to the second intermediate member. The curved path is preferably chosen to cause the sash to remain clear of the frame as the sash opens and closes. When the sash is fully closed, the pivotal connection between the sash member and the second intermediate member is preferably positioned inwardly of the pivotal connection between the second intermediate member and the frame member, the pivotal connections defining a line which is substantially perpendicular to the plane of the sash.

The position of both pivotal connections between the frame member and the intermediate members are preferably selectively movable relative to the frame, as the sash moves relative to the frame. The arrangement may further comprise a releasable locking arrangement operable to select the pivotal connection of the first intermediate member for movement, except when the locking arrangement is overcome. The window stay arrangement of the second aspect may further incorporate the features of the window stay arrangement of the first aspect of the invention, as set out above. Embodiments of the present invention will now be described in more detail, by way of example only, and with reference to the accompanying drawings, in which:-

5 Figs. 1A, 1B and 1C illustrate a closed, intermediate and fully open condition of a first stay arrangement according to the present invention, during egress operation;

Figs. 2A, 2B, 2C and 2D are views at the viewing and section lines A-A, B- 10 B, C-C and D-D in Fig. 1;

Figs. 3A and 3B show intermediate and fully open conditions during easy- clean operation;

15 Figs. 4A and 4B are section views at A-A and B-B in Fig. 3;

Figs. 5A, 5B and 5C illustrate a closed, intermediate and fully open condition of a second stay arrangement according to the present invention, during egress operation; 20 Figs. 6A, 6B, 6C and 6D are views at the viewing and section lines A-A, B- B, C-C and D-D in Fig. 5;

Figs. 7A and 7B show intermediate and fully open conditions during easy- 25 clean operation;

Figs. 8A to 8H are schematic diagrams showing the movement of a sash within a frame, interconnected by means of the stay arrangement of the preceding figures.

30. Principal Components and Connections (First Embodiment)

Reference to Fig. 1, and particularly Fig. 1B, allows the principal components of the illustrated stay arrangement, and the connections between 35 them, to be described. The stay arrangement 10 includes a sash arm 12 which is fixed, upon installation, to a sash indicated at 14. The sash 14 is to be mounted for opening and closing in a frame indicated at 16, by means of the stay arrangement 10. A track 18 is mounted, in use, to the frame 16. The track 18 carries first and second carriages 20, 22 which can slide along the track 18, subject to constraints to be described, as the sash 14 moves relative to the frame 16.

The carriages 20, 22 are connected to the sash arm 12 by a pivot linkage formed by a first intermediate arm 24, and a second intermediate arm 26.

The first intermediate arm 24 is pivotally connected at 28 to the first carriage 20, to the sash arm 12 at 30 and to the second intermediate member 26 at 32. It is to be noted that the pivot 32 is positioned between the pivots 28 and 30. The second intermediate arm 26 is pivotally connected at 34 to the second carriage 22, at 36 to the sash arm 12 and, as has been described, at 32 to the first intermediate arm 24. It is to be noted that the pivot 36 is located between the pivots 32, 34. Further details of the manner in which the linkages move will be described below. At this stage, it is sufficient to note that in the egress operation illustrated in Fig. 1, the pivot 34 remains fixed relative to the track 18. The first carriage 20, and thus the pivot 28 move along the track 18 as the sash arm 12 moves between the fully closed position (Fig. 1A) and the fully open position (Fig. 1C), through the intermediate position (Fig. 1B). During the alternative easy-clean operation (Fig. 3), the first carriage 20, and thus the pivot 28 remain fixed relative to the track 18, while the second carriage 22, and thus the pivot 34, move along the track 18, as the sash arm 12 moves between the fully closed position (as shown in Fig. 1A) and the fully open position (Fig. 3B), through the intermediate position (Fig. 3A).

Locking Arrangement (First Embodiment)

The choice of which carriage 20, 22 is to move is governed by arrangements which can now be described. The track 18 is a shallow C-section (Fig. 2A). The side walls 38 and peripheral lips 40 reach around the carriages 20, 22 to entrap them within the track 18, but allow them to slide along the track and to be accessible between the lips 40. However, a leaf spring 42 (Fig. 2B) is mounted on the floor 44 of the track 18 and engages behind a step 46 in the second carriage 22, when the second carriage 22 is at the end of the track 18, in the position illustrated in Fig. 1. This prevents the second carriage 22 moving from this position, unless the leaf spring 42 is depressed. Consequently, the leaf spring 42 and step 46 form a releasable locking arrangement which locks the second carriage 22 at the position shown in Fig. 1.

Fig. 2C shows the first carriage 20, at the other end of the track 18, when the stay arrangement 10 is fully closed (Fig. 1A). In this position, the carriage 20 sits over a restraining member 48 located on the floor 44. The restraining member 48 is flexible and has a rib 50 running transverse to the track 18. The first carriage 20 also has transverse ribs 52. The ribs 50, 52 interfere with each other, but the resilience of the restraining member 48 allows the. rib 50 to deflect, allowing the first carriage 20 to move along the track. The result is an arrangement in which the first carriage 20 is restrained from movement, by the ribs 50, 52, but is not wholly prevented from movement.

The track 18 also includes a shuttle 54 (Figs. 1B and 1C), located between the first and second carriages 20, 22 and free to slide along the track 18. The shuttle 54 preferably fits in the track 18 with some friction, to prevent the shuttle 54 from sliding along the track 18 unless pushed.

In Fig. 2D, the shuttle is visible in the fully open egress operation position of the stay arrangement 10, in which the first carriage 20 has slid along the track 18 toward the second carriage 22, collecting the shuttle 54 as it moves, and pushing the shuttle 54 towards the second carriage 22. As the shuttle 54 approaches the second carriage 22, the shuttle 54 rides over the leaf spring 42, causing it to be depressed out of engagement with the step 46. The significance of this will become apparent below. Egress Operation (First Embodiment)

During normal operation, when the sash is in the closed position (Fig. 1A), and is to be opened, the stay arrangement 10 begins to move from the closed position (Fig. 1A). As it does so, engagement of the leaf spring 42 with the step 46 locks the second carriage 22 against movement. The first carriage 20 is restrained by the ribs 50, 52, but this restraint is not as strong as the locking provided by the leaf spring 42. Accordingly, it is the first carriage 20 which begins to move as the sash is opened.

Eventually, the intermediate position (Fig. 1B) is reached. The first carriage 20 has moved someway along the track 18 and has engaged the shuttle

54, beginning to push the shuttle 54 toward the second carriage 22. It is to be noted that the shuttle 54 has not reached the second carriage 22. In particular, the shuttle 54 has not engaged the leaf spring 42.

Commonly, a sash is not opened through a full 90° sweep, during normal use, but only to an angle less than 90°, such as that shown in Fig. 1B. Thus, during most normal use, the shuttle 54 will not reach the leaf spring 42. Consequently, if the sash is closed once again, the shuttle 54 will be left partway along the track 18, clear of the leaf spring 42. The second carriage 22 thus remains locked. Accordingly, the sash can be repeatedly opened and closed between these positions, in the manner described. In an emergency situation, the sash can be opened further, to the fully open position of Fig. 1C, in which the sash has swept through 90°. It can be seen that because the second carriage 22 is locked at the end of the track 18, the sash 14 is positioned at the end of the track 18 when in the position of Fig. 1 C, so that the area of the frame 16 available for emergency egress is maximised. In particular, it is not reduced at all by movement of the second carriage 22 along the track 18, from the end position illustrated. Easy-clean Operation (First Embodiment)

Having described egress operation, easy-clean operation can now be described, particularly with reference to Figs. 3A and 3B.

Easy-clean operation is initiated by first fully opening the sash 14 in normal egress operation (to the position of Fig. 1C) and then fully closing the sash 14. This brings the stay arrangement 10 to the condition illustrated in Fig. 1A, except that the shuttle 54 (not visible in Fig. 1A) will have been pushed right along the track 18, into engagement with the leaf spring 42. This depresses the leaf spring 42 to release the second carriage 22, as illustrated in Fig. 2D. When the first carriage 20 withdraws along the track 18, as the sash is closed, the shuttle 54 remains at the position shown in Fig. 2D and thus, the lock provided by the leaf spring 42 remains released. As the first carriage 20 reaches the end position (Fig. 2C), the restraining member 48 is again engaged.

Consequently, while the second carriage 22 is now released from the leaf spring 42, the first carriage 20 is restrained by the member 48. When the sash 14 is next opened, the second carriage 22 is free to move and it is thus this movement which takes place, with the first carriage 20 being held by the restraint of the member 48. Consequently, the pivot 28 remains fixed relative to the track 18, but the pivot 34 begins to move along the track 18, with the second carriage 22 riding over the leaf spring 42 (Fig. 4B). As the second carriage 22 moves along the track 18, it pushes the shuttle

54 before it, eventually reaching the position where the shuttle 54 contacts the first carriage 20, stopping the second carriage 22 from further movement. This corresponds with the position of Figs. 3B and 4B, with the sash 14 fully open, substantially perpendicular to the plane of the frame 16. In this position, it can readily be seen that a significant gap 55 has opened between the outer face 56 of the sash 14, and the end 58 of the track 18, at which the second carriage 22 was originally locked. This provides access generally in the region indicated at 60, for cleaning the outer face 56 from within the building. When the sash 14 is closed from the easy-clean position of Fig. 3B, the second carriage 22 slides back along the track 18 toward its original position, leaving the shuttle 54 behind it. Consequently, as the final position is reached, the second carriage 22 rides over the leaf spring 42, which then snaps behind the step 46 to restore the lock on the second carriage 22.

Thus, while easy-clean operation can readily be initiated by fully opening and then fully closing the sash 14 in egress operation, so that the next opening of the sash 14 will be in easy-clean operation, the arrangement will revert to egress operation as soon as the sash 14 is closed. Manual intervention is not required in order to revert to egress operation. All that is required is for the sash 14 to be fully closed.

Principal Components and Connections (Second Embodiment)

Reference to Fig. 5, and particularly Fig. 5B, allows the principal components of the second illustrated stay arrangement, and the connections between them, to be described. Many features of the second arrangement correspond with features of the first arrangement and are therefore given the same reference numeral, with the suffix A. The principal differences between the arrangements relate to the shuttle and to the carriage locking arrangements.

The stay arrangement 10A includes a sash arm 12A which is fixed, upon installation, to a sash indicated at 14A. The sash 14A is to be mounted for opening and closing in a frame indicated at 16A, by means of the stay arrangement 10A. A track 18A is mounted, in use, to the frame 16A. The track 18A carries first and second carriages 20A, 22A which can slide along the track 18A, subject to constraints to be described, as the sash 14A moves relative to the frame 16A.

The carriages 20A, 22A are connected to the sash arm 12A by a pivot linkage formed by a first intermediate arm 24A, and a second intermediate arm 26A. The first intermediate arm 24A is pivotally connected at 28A to the first carriage 20A, to the sash arm 12A at 30A and to the second intermediate member 26A at 32A. It is to be noted that the pivot 32A is positioned between the pivots 28A and 30A. The second intermediate arm 26A is pivotally connected at 34A to the second carriage 22A, at 36A to the sash arm 12A and, as has been described, at 32A to the first intermediate arm 24A. It is to be noted that the pivot 36A is located between the pivots 32A, 34A.

Further details of the manner in which the linkages move will be described below. At this stage, it is sufficient to note that in the egress operation illustrated in Fig. 5, the pivot 34A remains fixed relative to the track 18A. The first carriage 20A, and thus the pivot 28A move along the track 18A as the sash arm 12A moves between the fully closed position (Fig. 5A) and the fully open position (Fig. 5C), through the intermediate position (Fig. 5B). During the alternative easy- clean operation (Fig. 7), the first carriage 20A, and thus the pivot 28A remain fixed relative to the track 18A, while the second carriage 22A, and thus the pivot 34A, move along the track 18A, as the sash arm 12A moves between the fully closed position (as shown in Fig. 5A) and the fully open position (Fig. 7B), through the intermediate position (Fig. 7A).

Locking Arrangement (Second Embodiment)

The choice of which carriage 20A, 22A is to move is governed by arrangements which can now be described.

The track 18A is a shallow channel section with out-turned peripheral lips 40A (Fig. 6A). Lips 21 A on the carriage 20A reach around the side walls 38A and peripheral lips 40A to mount the carriage 20A on the track 18A, but allow it to slide along the track. A similar arrangement of lips mounts the carriage 22A on the track 18A. However, a leaf spring 42A (Fig. 6B) is mounted on the second carriage 22A, at the pivot 34. The spring 42A engages behind steps 46A cut in the walls 38A of the track 18A, when the second carriage 22A is at the end of the track 18A, in the position illustrated in Fig. 5. This prevents the second carriage 22A moving from this position, unless the leaf spring 42A is deflected to disengage the steps 46A. Consequently, the leaf spring 42A and step 46A form a releasable locking arrangement which locks the second carriage 22A at the position shown in Fig. 5.

Fig. 6C shows the first carriage 20A, at the other end of the track 18A, when the stay arrangement 10A is fully closed (Fig. 5A). The carriage 20A sits in a well 49 in a restraining member 48A. The member 48A is able to move along the channel of the track 18A, when pulled or pushed by the carriage 20A, but provides resistance to movement by friction between the member 48A and the track 18A. The restraining member 48A may be a moulded plastics component, which is an interference fit in the channel.

The arrangement 10A also includes a shuttle 54A (Figs. 5B and 5C), located between the second carriage 22A and the lips 40A of the channel. The shuttle 54A is able to slide along the lips 40A, but is constrained to a range of positions relative to the second carriage 22A, by a pip 51 carried by the shuttle

54A and running in a slot 53 in the second carriage 22A.

The shuttle 54A is formed of spring metal or other spring material and has a lip 55 which engages the spring 42A to raise the spring 42A clear of the steps 46A, when the shuttle 54A is forced in the direction of the pivot 34A, as will be described.

In Fig. 6D, the shuttle is visible in the fully open egress operation position of the stay arrangement 10A, in which the first carriage 20A has slid along the track 18A toward the second carriage 22A, engaging the shuttle 54A as it reaches the first carriage 20A, and pushing the shuttle 54A towards the pivot 34A. This causes the lips 55 to engage the spring 42A and release it from the steps 46A. The significance of this will become apparent, below.

Egress Operation (Second Embodiment)

During normal operation, when the sash is in the closed position (Fig. 5A), and is to be opened, the stay arrangement 10A begins to move from the closed position (Fig. 5A). As it does so, engagement of the leaf spring 42A with the steps 46A locks the second carriage 22A against movement. The first carriage 20A is restrained by the friction of the member 48A, but this restraint is not as strong as the locking provided by the leaf spring 42A. Accordingly, it is the first carriage 20A which begins to move as the sash is opened. Eventually, the intermediate position (Fig. 5B) is reached. The first carriage 20A has moved someway along the track 18A. It is to be noted that the first carriage 20A has not yet encountered the shuttle 54A.

Commonly, a sash is not opened through a full 90° sweep, during normal use, but only to an angle less than 90°, such as that shown in Fig. 5B. Thus, during most normal use, the first carriage 20A will not reach the shuttle 54A. Consequently, if the sash is closed once again, the second carriage 22A remains locked. Accordingly, the sash can be repeatedly opened and closed between these positions, in the manner described, with the first carriage 20A moving and the second carriage 22A remaining locked by the spring 42A.

In an emergency situation, the sash can be opened further, to the fully open position of Fig. 5C, in which the sash has swept through 90°. It can be seen that because the second carriage 22A is locked at the end of the track 18A until the final sash position is reached, the sash 14A is positioned at the end of the track 18A when in the position of Fig. 5C, so that the area of the frame 16A available for emergency egress is maximised. In particular, it is not reduced at all by movement of the second carriage 22A along the track 18A, from the end position illustrated.

Eas -clean Operation (Second Embodiment)

Having described egress operation, easy-clean operation can now be described, particularly with reference to Figs. 7A and 7B.

Easy-clean operation is initiated by first fully opening the sash 14A in normal egress operation (to the position of Fig. 5C) and then fully closing the sash 14A. This brings the stay arrangement 10A to the condition illustrated in

Fig. 5A, except that the shuttle 54A (not visible in Fig. 5A) will have been pushed by the first carriage 20A toward the pivot 34A to engage and release with the leaf spring 42A. This releases the second carriage 22A, as illustrated in Fig. 6D. When the first carriage 20A withdraws along the track 18A, as the sash is closed, the shuttle 54A remains at the position shown in Fig. 6D and thus, the lock provided by the leaf spring 42A remains released. As the first carriage 20A moves the resistance provided by the restraining member 48A will remain.

Consequently, while the second carriage 22A is now released from the leaf spring 42A, the first carriage 20A is still restrained by the member 48. When the sash 14A is next opened, the second carriage 22A is free to move and it is thus this movement which takes place, with the first carriage 20A being held by the friction of the restraining member 48A. Consequently, the pivot 28A remains fixed relative to the track 18A, but the pivot 34A begins to move along the track 18A, with the second carriage 22A. The leaf spring 42A (Fig. 8B) rides along the lips 40A, having been released from the steps 46A.

As the second carriage 22A moves along the track 18A, it pushes the shuttle 54A before it, eventually reaching the position where the shuttle 54A contacts the first carriage 20A, stopping the second carriage 22A from further movement. This corresponds with the position of Figs. 7B and 8B, with the sash 14A fully open, substantially perpendicular to the plane of the frame 16A. In this position, it can readily be seen that a significant gap 55A has opened between the outer face 56A of the sash 14A, and the end 58A of the track 18A, at which the second carriage 22A was originally locked. This provides access generally in the region indicated at 60A, for cleaning the outer face 56A from within the building.

When the sash 14A is closed from the easy-clean position of Fig. 7B, the second carriage 22A slides back along the track 18A toward its original position, leaving the shuttle 54A behind it, until the shuttle 54A has moved to the other end of its range relative to the second carriage 22A, furthest from the pivot 34A. Consequently, as the final position of the second carriage 22 is reached, the leaf spring 42 snaps down into the steps 46A to restore the lock on the second carriage 22A. Thus, while easy-clean operation can readily be initiated by fully opening and then fully closing the sash 14A in egress operation, so that the next opening of the sash 14A will be in easy-clean operation, the arrangement will revert to egress operation as soon as the sash 14A is closed. Manual intervention is not required in order to revert to egress operation. All that is required is for the sash 14A to be fully closed.

Sash Motion (Both Embodiments) The motion of the stay arrangements can now be described in more detail, with particular reference to Figs. 1B, 1C and Fig. 8. For simplicity, the stay motion is described and shown with reference to the numerals used for the first embodiment, but it is to be understood that the stay motion of both embodiments is the same.

Turning first to Figs. 1B and 1C, it can be seen that the pivots 28, 30, 32 and 34 are simple pivot connections, but that the pivot arrangement 36 incorporates a curved slot 62 so that, in addition to the second intermediate arm 26 pivoting relative to the sash arm 12, at the pivot 36, the position of the pivots 36 moves relative to the second intermediate arm 26, along the curve defined by the slot 62. At any position within the range of possible movement, the position of the pivot 36 along the slot 62, and thus the shape of the slot 62, determines the angle of the sash arm 12 about the pivot 30 and thus, determines the angle of the sash 14 relative to the frame 16.

Modification of the slot shape thus allows the motion of the sash 14 to be modified, for example to ensure that seals are not trapped, or to accommodate different sash or frame profiles without fouling each other as they move. This can best be seen from Figs. 8A to 8H. In these schematic diagrams, the second intermediate arm 26 is illustrated without the slot 62. Instead, the drawings maintain the correct relative positions of the various components as determined by the pivots 28, 30, 32 and 34 while also allowing a minimum clearance 64 to be maintained between the sash 14 and the frame 16. Maintaining this minimum clearance 64 determines, at each position, the position occupied by the pivot 36, relative to the second intermediate arm 26. This is illustrated in Fig. 5 as a circle drawn on the arm 26.

Consequently, by tracking the sash 14 as it opens from the position of Fig. 8A to the position of Fig. 8H, a series of positions 65 for the pivot 36 can be plotted, finally being joined (Fig. 8H) to define the shape of the slot 62.

Security (Both Embodiments) It can be seen from Fig. 1A, for example, that when the sash 14 is fully closed, the pivot 36 lies directly behind the pivot 34. That is, the pivots 34, 36 define a line generally perpendicular to the plane of the frame 16. This provides security by resisting attempts to prise the sash 14 away from the frame 16. Moreover, the end of the sash arm 12 can be provided with a security projection (not shown) which engages in a recess in the frame 16 to provide a deadbolt action, further resisting prising of the sash 14, and taking prising forces in place of the pivots.

Variations and Modifications

It is envisaged that many variations and modifications can be made to the arrangements described above, without departing from the scope of the invention. In particular, many different shapes, sizes and relative shapes and sizes of the various components could be chosen.

It is envisaged that the arrangement for locking and unlocking the carriages could be used in conjunction with a conventional window stay which does not incorporate the curved slot and associated features. It is also envisaged that the curved slot and associated features could be used in a stay arrangement which did not incorporate the locking arrangements for the carriages, such as one in which the pivot 34 is permanently fixed in position, so that only egress operation was possible.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A window stay arrangement comprising:- a track member for attachment to a window frame; a sash member for attachment to a sash to be mounted for opening and closing in the frame; first and second carriage members which, in use, are able to move along the track member; a pivot linkage connecting the track member and the sash member and including first and second arms pivotally connected to the sash and to a respective carriage member; a releasable locking arrangement operable to lock at least one of the carriage members against movement along the track member; and release means operable to release the locking arrangement when the sash is moved to a predetermined position.

2. An arrangement according to claim 1 , wherein the predetermined position is the fully open position.

3. An arrangement according to claim 1 or 2, wherein the locking arrangement is operable to lock only one of the carriage members.

4. An arrangement according to claim 3, wherein the other carriage member is associated with a restraining arrangement which resists movement of the restrained carriage from an initial position, the restraint being overcome when the said one carriage member is locked, but not when the locking arrangement is released, whereby the restrained carriage will move along the track member when the sash is moved with the locking arrangement engaged, and the said one carriage will move from a corresponding initial position when the sash is moved with the locking arrangement disengaged.

5. An arrangement according to claim 4, wherein the said initial positions correspond with the sash being closed in the frame.

6. An arrangement according to any preceding claim, wherein the locking arrangement re-engages as the said one carriage returns to the initial position.

7. An arrangement according to any preceding claim, wherein the locking arrangement comprises a sprung member which blocks movement of the said one carriage member when in an advanced position, and is retractable by action of the release means to release the said one carriage member.

8. An arrangement according to any preceding claim, wherein the release means comprises a shuttle member movable to a position at which the shuttle member causes the release means to release the locked carriage.

9. An arrangement according to claim 8, wherein, in use, the or a carriage member engages the shuttle member to move the shuttle member to release the locked carriage.

10. An arrangement according to claim 8 or 9, wherein the shuttle is positioned between the carriage members.

11. An arrangement according to claim 8, 9 or 10, wherein when the locking member is engaged, the shuttle member is moved by the unlocked carriage member as the unlocked carriage member approaches the locked carriage member.

12. An arrangement according to any of claims 8 to 11, wherein the shuttle member reaches the locking arrangement, to release the locking arrangement, only when the sash is moved substantially to its fully open position.

13. An arrangement according to any of claims 8 to 12, wherein movement of the lockable carriage member, when the locking arrangement is released, moves the shuttle member away from the locking arrangement, allowing the locking arrangement to re-engage.

14. An arrangement according to any of claims 8 to 13, wherein the shuttle member is constrained to a range of positions relative to the lockable carriage member.

15. A window stay arrangement comprising:- a frame member for attachment to a window frame; a sash member for attachment to a sash to be mounted for opening and closing in the frame; first and second intermediate members pivotally connected to the frame member and to the sash member; the second intermediate member being pivotally connected to the first intermediate member at a position between the pivotal connections of the first intermediate member to the frame member and the sash member; the sash member being pivotally connected to the second member at a position between the pivotal connections of the second intermediate member to the frame member and the first intermediate member; the position of the pivotal connection between the frame member and one of the intermediate members being movable relative to the frame member; and the position of the pivotal connection between the sash member and the second intermediate member being movable relative to the second intermediate member, as the sash member moves relative to the frame member.

16. An arrangement according to claim 15, wherein the pivotal connection between the sash member and the second intermediate member is constrained to move along a curved path relative to the second intermediate member.

17. An arrangement according to claim 16, wherein the curved path is chosen to cause the sash to remain clear of the frame as the sash opens and closes.

18. An arrangement according to any of claims 15 to 17, wherein when the sash is fully closed, the pivotal connection between the sash member and the second intermediate member is positioned inwardly of the pivotal connection between the second intermediate member and the frame member, the pivotal connections defining a line which is substantially perpendicular to the plane of the sash.

19. An arrangement according to any of claims 15 to 18, wherein the position of both pivotal connections between the frame member and the intermediate members are selectively movable relative to the frame, as the sash moves relative to the frame.

20. An arrangement according to any of claims 15 to 19, wherein the arrangement further comprises a releasable locking arrangement operable to select the pivotal connection of the first intermediate member for movement, except when the locking arrangement is overcome.

21. An arrangement according to any of claims 15 to 20 and any of claims 1 to 14.

22. A window stay arrangement substantially as described above, with reference to the accompanying drawings.

23. Any novel subject matter or combination including novel subject matter disclosed herein, whether or not within the scope of or relating to the same invention as any of the preceding claims.