GB2130285A - Releasable fastenings for doors or windows - Google Patents

Abstract

The fastening comprises an elongate base member 10 formed with two spaced apertures 11, two headed elements 18 for co-operation with the apertures, two elongate wire springs 12 co-extending in spaced relationship along the base member 10, the springs, adjacent opposite ends, overlapping the apertures 11, two longitudinally spaced supports 13 for each spring mounted on the base member between the apertures, and actuating means 15, 16 17 engageable with the wire springs at a location between the supports for effecting movement of the springs selectively towards or away from one another at said location, whereby the consequent bending movement of the springs 12 moves their ends which overlap the apertures selectively between a position where they retain the headed elements in the apertures 11 and a position where the headed elements are free to withdraw from the apertures. <IMAGE>

Description

SPECIFICATION Improvements in or relating to releasable catch mechanisms for doors or windows The invention relates to releasable catch mechanisms for doors or windows. Although the catch mechanism according to the invention may be used on conventional hinged doors or windows, it is particularly applicable to sliding doors or windows in which one part of the catch mechanism is mounted in the upright edge of the sliding door or window and co-operates with another part mounted on the fixed upright frame member against which the edge of the door or window abuts when closed.

According to the invention a releasable catch mechanism, for securing the movable part of a door or window to the fixed part thereof when the door or window is in a closed position, comprises at least one headed element for mounting on one part of the door or window, and a co-operating retaining device for mounting on the other part of the door or window and comprising a base member formed with an aperture through which the head and at least part of the neck of the headed element pass as the door or window is moved to the closed position, a detent element mounted on the base member for movement relatively thereto between a retaining position, where it extends partly across said aperture and engages behind the head of the headed element to prevent withdrawal thereof from the base member, and a free position where it is disengaged from the headed element, and actuating means for effecting movement of the detent element between said retaining and free positions.

Preferably the detent element is movable from the retaining position to the free position against the action of spring means, independently of operation of the actuating means.

With such an arrangement the mechanism may then act as a spring catch and allow the door or window to be closed and retained in the closed position without the necessity of operating the actuating means. The actuating means then, of course, require to be operated to move the detent element to the free position to allow the door or window to be opened. Such an arrangement is an improvement over certain existing releasable catch mechanisms where no such spring catch facility is provided and the mechanism is therefore liable to be damaged should an attempt be made to close the door or window with the catch already in the retaining position. The required spring means may be provided by the resilience of the detent element itself or by a spring acting on and restraining a displaceable detent element.

The detent element may comprise an elongate element supported, intermediate the ends thereof, on the base member, a portion to one side of the support co-operating with said headed element and a portion to the other side of the support co-operating with said actuating means, operation of the actuat ing means being arranged to pivot the elon gate element about its support and thereby move it between the retaining and free posi tions.

The elongate element may comprise a resili ently bendable element such as a wire spring, for example of rectangular cross section.

Preferably there are provided two detent elements co-operating with the aperture in the base member and engageable with opposite sides respectively of the headed element, movement of both detent elements being ef fected simultaneously by said actuating means. In the case where each detent element comprises an elongate element, the two ele ments may comprise co-extending spaced por tions which, when the actuating means are operated, are moved towards or away from one another between the retaining and free positions. The actuating means may, for example, comprise a cam device disposed between the elongate elements, whereby rota tion of the cam urges the aforesaid portions of the elements towards or away from one another.

In any of the above arrangements the or each detent element may be normally dis posed in the free position and arranged to be moved into said retaining positon by operation of the actuating means. Alternatively, the ele ment may be normally disposed in the retain ing position and arranged to be moved into the free position by operation of the actuating means.

In any of the above arrangements the catch mechanism preferably comprises two or more spaced assemblies each comprising an aper ture in the base member, at least one detent element associated with the aperture, and a headed element co-operating with the aper ture and detent element. In this case the detent elements of two or more assemblies may be arranged to be moved by one and the same actuating means.

In a preferred embodiment of the invention the catch mechanism comprises an elongate base member formed with two spaced aper tures, two headed elements for co-operation with said apertures respectively, two elongate wire springs co-extending in spaced relation ship along the base member, the springs, adjacent opposite ends thereof, overlapping the apertures respectively, two longitudinally spaced supports for each spring mounted on the base member between said apertures, and actuating means engageable with the wire springs at a location between said supports for effecting movement of the springs selec tively towards or away from one another at said location, whereby the consequent bend ing movement of the springs moves the ends thereof which overlap the apertures selectively between said retaining and free positions.

The following is a 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 diagrammatic perspective view of the essential elements of a catch mechanism according to the invention, Figure 2 is a plan view of the mechanism in the free position, Figure 3 is a plan view of the mechanism in the retaining position, Figure 4 is a side elevation of the mechanism, and Figure 5 is an end elevation of the mechanism.

Only the essential elements of the mechanism are shown diagrammatically in the drawings, in order that the working of the mechanism may be clearly understood, and it will be appreciated that the mechanism will also comprise other components which are not shown, such as casing and mounting parts The mechanism comprises an elongate base plate 10 formed with two spaced apertures 11 each of which is elongate with rounded ends.

Two spaced elongate spring steel wires 1 2 extend longitudinally of the base plate 10 and are located by being passed through apertures provided by two longitudinally spaced support bridges 13 mounted on the base plate 10. In the arrangement shown the wires 12 are of rectangular cross-section although it will be appreciated that elements of other cross-section may be employed.

The opposite ends of the wires 12 lie adjacent stop bars 14 mounted on the base plate 10. The stop bars 14 serve merely to prevent longitudinal displacement of the wires 12 and do not otherwise affect movement of the wires.

Mounted on a support (not shown) which is fixed in relation to the base plate 10, at about the mid-point thereof, is a pivot pin 1 5 (Fig.

2) carrying a circular cam 1 6 which is generally wedge-shaped in cross-section, as best seen in Fig. 5. A portion of the periphery of the cam 1 6 projects into the gap between the central portions of the wires 12, as best seen in Fig. 4, and the cam may be rotated by means of an actuating lever 1 7 mounted on the pivot pin 15.

The base plate 1 0 and the components associated therewith are mounted on one part of a door or window. For example, the base plate is mounted vertically in the upright edge of the movable part of a sliding door.

Mounted on the fixed upright frame member of the door, against which the edge of the sliding part abuts when the sliding door is closed, are two spaced headed studs 18, the shanks 1 9 of the studs extending in the closing direction of the door, i.e. towards the sliding part of the door. Alternatively, the base plate 10 may be mounted on the fixed frame member and the studs 18 mounted on the sliding door.

The headed studs 18 are so disposed as to pass through the apertures 11 respectively when the door is closed. The studs may be mounted on a base plate to ensure that, when fitted, they are in the correct spaced relationship.

In the normal, free position of the catch mechanism shown in Fig. 2, the wires 12 are parallel and the narrower tapered portion of the cam 1 6 is disposed between the central portions of the wires. In this position, therefore, the end portions of the wires 12 lie on opposite sides of the associated aperture 11 and the enlarged head 20 of the associated stud 18 can pass freely into the aperture as the door is closed.

After the door has been closed the lever 1 7 is swung through 180 so as to force the thicker portion of the wedge-shaped cam 1 6 into the gap between the central portions of the wires 1 2. The central portions are thus forced apart, as shown in Fig. 3, and this forces together the opposite end portions of the wires so that they engage the shanks 19 of the studs 18 behind the enlarged heads 20 of the studs, as shown in Figs. 3 and 4. The ends of the wires thus prevent withdrawal of the headed studs 1 8 through the apertures 11 and thus retain the door in the closed position.There may be associated with the pivot pin 15, cam 16 and lever 1 7 a key operated locking mechanism which, in conventional manner, may be operated to prevent actuating of the lever 1 7 and thus opening of the the door.

When it is required to open the door, the lever 1 7 is swung back through 180= so as to bring the narrower portion of the cam 1 6 between the wires 1 2. Due to their natural resilience the wires 1 2 return to the parallel position shown in Fig. 2 and become disengaged from the studs 18, thus permitting withdrawal of the studs through the apertures 11.

If the mechanism should be moved to the retaining position shown in Fig. 3 while the door is open, and an attempt subsequently made to shut the door, the tapered heads 20 of the studs 18 will simply engage the wires 1 2 and will force them apart, this being permitted by the resilience of the wires, until the heads 20 have cleared the wires permitting the wires to snap together against the shanks of the studs behind the heads. The door may thus be closed and will be retained closed without damage to the catch mechanism.

If the described arrangement operation of the cam 1 6 is arranged to move the wires to the retaining position. It will be appreciated, however, that the wires could be arranged to be normally in the retaining position, operation of a suitable shaped cam being arranged to squeeze together the central portions of the wires, thus moving the ends of the wires apart to the free position.

The arrangement shows two headed studs for engagement with the mechanism but any number of stud, aperture and wire assemblies may be employed to provide retaining points at various locations spaced apart along the edge of a door or window. Thus, there may be provided a number of mechanisms of the kind illustrated along the edge of the door or window, each mechanism comprising two wires operated on by a cam and the cams being interconnected, for example by some form of push rod, so that all the mechanisms may be operated by operation of a single manipulating element.

The arrangement is applicable to hinged doors or windows as well as to sliding doors or windows. In the case of a hinged door one part of the mechanism will be mounted on the main face of the door adjacent the free edge thereof, rather than on the narrow door edge, and the other part of the mechanism will be mounted on a stop bar on the fixed door frame, which bar is engaged by the door when closed.

Although in the arrangement shown there are provided two wires associated with each aperture 11, this is not essential and in some arrangements only a single such element may be provided for engaging one side only of the headed stud. In this case the headed stud may be generally hook-shaped.

In the arrangement described, for simplicity the spring means which permits resilient displacement of the detent elements by the headed studs is provided by the resilience of the wires themselves. However, in an alternative arrangement the wires may be replaced by displaceable rigid elements the displacement of which is restrained by separate spring means. For example, each wire might be replaced by a pivotally mounted rod on which a compression or leaf spring acts.

The cam mechanism illustrated is by way of example only and it will be appreciated that any other suitable form of actuating mechanism could be provided to effect the necessary movement of the wires. A cam mechanism is preferred but this could be any other suitable form of cam mechanism, for example a linearly movable cam or wedge rather than the rotatable cam described: The stop bars 14, in addition to preventing longitudinal movement of the wires 12, may also be shaped to the limit the lateral displacement of the wires. Thus in the arrangement illustrated in the drawings each stop bar 14 may have projecting lugs at opposite ends thereof against which the ends of the wires 1 2 abut. In the alternative arrangement, referred to earlier, where the ends of the wires are displaced outwardly to release the studs 18, each bar 14 may have a single projecting lug disposed between the ends of the wires to limit their movement towards one another.

Claims (16)

1. A releasable catch mechanism, for securing the movable part of a door or window to the fixed part thereof when the door or window is in a closed position, comprising at least one headed element for mounting on one part of the door or window, and a cooperating retaining device for mounting on the other part of the door or window and comprising a base member formed with an aperture through which the head and at least part of the neck of the headed element pass as the door or window is moved to the closed position, a detent element mounted on the base member for movement relatively thereto between a retaining position, where it extends partly across said aperture and engages behind the head of the headed element to prevent withdrawal thereof from the base member, and a free position where it is disengaged from the headed element, and actuating means for effecting movement of the detent element between said retaining and free positions.

2. A catch mechanism according to claim 1, wherein the detent element is movable from the retaining position to the free position against the action of spring means, independently of operation of the actuating means.

3. A catch mechanism according to claim 2, wherein said spring means are provided by the resilience of the detent element itself.

4. A catch mechanism according to claim 2, wherein said spring means comprise a spring acting on and restraining a displaceable detent element.

5. A catch mechanism according to any of claims 1 to 4, wherein the detent element comprises an elongate element supported, intermediate the ends thereof, on the base member, a portion to one side of the support co-operating with said headed element and a portion to the other side of the support cooperating with said actuating means, operation of the actuating means being arranged to pivot the elongate element about its support and thereby move it between the retaining and free positions.

6. A catch mechanism according to claim 5, wherein the elongate element comprises a resiliently bendable element.

7. A catch mechanism according to claim 6, wherein the bendable element is a wire spring.

8. A catch mechanism according to claim 7, wherein the wire spring is of rectangular cross section.

9. A catch mechanism according to any of claims 1 to 8, wherein there are provided two detent elements co-operating with the aperture in the base member and engageable with opposite sides respectively of the headed element, movement of both detent elements being effected simultaneously by said actuating means.

10. A catch mechanism according to claim 9, wherein each detent element comprises an elongate element and the two elements comprise co-extending spaced portions which, when the actuating means are operated, are moved towards or away from one another between the retaining and free positions.

11. A catch mechanism according to claim 10, wherein the actuating means comprise a cam device disposed between the elongate elements, whereby rotation of the cam urges the aforesaid portions of the elements towards or away from one another.

1 2. A catch mechanism according to any of claims 1 to 11, wherein the or each detent element is normally disposed in the free position and is arranged to be moved into said retaining position by operation of the actuating means.

1 3. A catch mechanism according to any of claims 1 to 11, wherein the or each detent element is normally disposed in the retaining position and is arranged to be moved into the free position by operation of the actuating means.

14. A catch mechanism according to any of claims 1 to 13, comprising two or more spaced assemblies each comprising an aperture in the base member, at least one detent element associated with the aperture, and a headed element co-operating with the aperture and detent element.

1 5. A catch mechanism according to claim 14, wherein the detent elements of two or more assemblies are arranged to be moved by one and the same actuating means.

16. A catch mechanism according to claim 15, and comprising an elongate base member formed with two spaced apertures, two headed elements for co-operation with said apertures respectively, two elongate wire springs co-extending in spaced relationship along the base member, the springs, adjacent opposite ends thereof, overlapping the apertures respectively, two longitudinally spaced supports for each spring mounted on the base member between said apertures, and actuat ing means engageable with the wire springs at a location between said supports for effecting movement of the springs selectively towards or away from one another at said location, whereby the consequent bending movement of the springs moves the ends thereof which overlap the apertures selectively between said retaining and free positions.

1 7. A catch mechanism substantially as hereinbefore described with reference to the accompanying drawings.