GB2192927A - A casement fastener with security device - Google Patents

Abstract

A casement fastener is described having a lever handle 6 mounted on a base plate 7 for pivotal movement about axis 8 between open and closed positions and a security device mounted on the underside of the handle 6 for engagement with the base plate 7 in the closed position to prevent pivotal movement of the handle 6 to the open position until manually released. The security device comprises a retainer member 12 pivotally mounted about axis 13 on the handle 6 and biassed by a spring 16 to engage an abutment end 18 of the member 12 in a recessed formation 19 in the base plate 7 in the closed position. The other end of the member 12 is provided with an actuating portion 15 arranged to protrude through an access opening 14 in the handle 6 by means of which the member 12 may be pivotted against the biassing of the spring 16 to release the abutment end 18 from the recessed portion 19 and permit pivotal movement of the handle 6 to the open position. <IMAGE>

Description

SPECIFICATION A casement fastener with security device This invention relates to a casement fastener with a security device to prevent inadvertent opening of the fastener and to hold the fastener in the closed position.

This invention concerns casement fasteners of the conventional kind comprising a handle assembly and a striker and wherein a lever handle is mounted on a base plate for pivotal movement to engage the striker to maintain the casement closed, the handle assembly may be mounted either on the casement frame or on the fixed window frame with the striker being mounted respectively either on the fixed window frame or on the casement frame. The relative disposition of the two main component parts of the fastener, the handle assembly and the striker, does depend on the design and requirement for the type of window.In addition, there are generally two kinds of casement fastener with a pivotal handle, and these are referred to in the trade as a "cockspur or spur" handle in which the handle has a nose or lug projecting therefrom for engagement with a striker having a keep portion, and a "wedge" handle in which the handle lacks a nose but provides a face for abutment and engagement with a striker plate usually of wedge form.

In this Specification, the term "casement fastener" is deemed to cover fasteners of the conventional kind as just described.

It has already been recognised that in a casement fastener of the kind described, it is advantageous to provide a security device to maintain the fastener in the closed position to prevent inadvertent opening or movement of the handle. In many instances, the security device is also designed to prevent unauthorised opening of the window as a burglar deterrent or as a child-proof feature.

In the security devices that have been proposed previously, it has been common to provide some form of lock or locking device which is operated by a loose key or the like that has to be manipulated to actuate the device.

A common prior arrangement is a threaded grub screw that is mounted in the handle and which has to be turned by a key-like actuator to bring the grub screw into engagement with a recess formed in the base plate of the handle to prevent rotation of the handle relative to the base plate. To release the handle, it is necessary to use the key-like actuator to rotate the grub screw. In another common arrangement, instead of a grub screw, there is a cylinder lock which has to be actuated to drive a pawl or detent device either preventing rotation of the handle on the pivot or to secure the handle to the base plate on which it is pivotally mounted.

In both of these known arrangements, the user has to use a key or key-like actuator, and of course there is the problem of losing or maintaining the key or key-like actuator in a safe place. Additionally, for many persons, the actual use of the key or key-like actuator requires a degree of manual dexterity, and this often presents problems for the elderly and or handicapped.

Accordingly, it is an object of this invention to provide an improved casement fastener of the kind described having a security device not requiring any separate key or key-like actuator.

It is a further object of this invention to provide a casement fastener of the kind described wherein a simple form of security device is incorporated in the handle assembly for easy operation by a user to maintain the handle assembly in the closed position but releasable in an easy manner.

Other objectives of this invention will be appreciated with reference to the specific exemplary embodiments of this invention as described later herein.

According to this invention, we provide a casement fastener of the kind described and wherein the handle assembly comprises a base plate, a lever handle mounted on the base plate by a pivot for pivotal movement between an open position and a closed position, the base plate being provided with a recessed formation for engagement by a retainer when the handle is in the closed position, the retainer comprising a member pivotally mounted on the handle and biassed towards the base plate by spring means, the member having an abutment end extending to one side of the pivot mounting for engagement with the recessed formation and the member having an actuation end extending to the other side of the pivot mounting with the actuation end having a portion accessible to the user whereby on depressing the portion relative to the lever handle the abutment end is moved in the opposed sense to release the retainer from engagement with the recessed formation of the base plate to permit the lever handle to be moved from the closed position to the open position, and on movement of the lever handle from the open position to the closed position, the spring-loading of the retainer enables the abutment end to be displaced to engage in the recessed formation to hold the lever handle in the closed position.

By this invented casement fastener, the lever handle mounts the retainer which serves as a security device that is actuated in a simple manner by merely depressing the portion of the retainer member to release the abutment end from engagement with the base plate. No separate key or key-like member is required and the manual operation is analogous to pushing a button or knob to release the handle.

Preferably, the lever handle has a section of inverted channel shape in which the retainer is mounted for such pivotal movement with the portion of the actuation end of the retainer member protruding through an access opening or aperture formed in the lever handle.

With such preferred arrangement, the retainer is received between two opposed side walls of the lever handle and is secreted or concealed therebetween to preclude interference or damage.

Conveniently, the base plate is formed with lead-in or ramp faces adjoining the recessed formation whereby the abutment end of the retainer engages such ramp faces for guided movement to ride over same when the lever handle is turned from the open to closed positions.

By such an arrangement of the ramp faces, then the abutment end of the retainer will automatically reengage the recessed formation in the base plate when the lever handle is moved to the closed position, and the retainer member only has to be actuated by depressing the accessible portion for releasing the lever handle from the closed position.

Other features of the invented casement fastener will be understood from the description of exemplary embodiments given later herein, and it will be understood that this invention may be applied to a very wide range of styles and designs of casement fasteners.

This invention will now be described with reference to exemplary embodiments as shown in the accompanying drawings wherein: FIGURE 1 is a plan view of a casement fastener with a striker shown in the closed position; FIGURE 2 is a side elevation of the fastener shown in Figure 1; FIGURE 3 is a sectional detail view of the fastener shown in Figure 1 and taken on line 3'-3' of Figure 1; FIGURE 4 is a detail schematic view taken generally on line 4'-4' of Figure 3 showing the handle in the closed secured position; FIGURE 5 is a view similar to that of Figure 4 but showing the handle in the released position; and FIGURE 6 is a partly sectioned side elevation of an alternative embodiment of the casement fastener.

With reference to the drawings of Figures 1 and 2, the casement fastener comprises a handle assembly 1 and a striker 2. In known manner the striker 2 is adapted by holes or the like for securing to a fixed window frame 3a whilst the handle 1 is secured to a casement frame 3b. The striker has a mounting base 4 from which projects a striker lug 5 onto or over which the handle 1 is arranged to engage when in the closed position as shown in Figures 1 and 2.

The handle assembly 1 comprises a lever handle 6 mounted on a base plate 7 by a pivot pin 8 for opening and closing movement as depicted by the arrows in Figure 1. The base plate 7 is provided with holes 7a (see Figure 3) for use in securing the handle assembly to the casement frame.

In known manner, the head of the handle 6 is formed with an opening 9 in which the striker lug 5 may be received when the fastener is the- the closed position to hold the casement frame 3b slightly ajar or spaced from the window frame 3a to provide a night vent or ventilating location. Also in known manner, the base plate 7 is formed with a seating 10 for receiving the striker lug 5 as shown in Figure 2 when the fastener is in the closed position to hold the casement in the fully closed position engaging the window frame 3a.

It will be understood that the style or type of casement handle and lever handle may be varied as desired and this invention may be applied to other kinds of striker and handle arrangements on casement and window frames.

With reference now also to Figures 3,4 and 5, the lever handle 6 includes a section 6a which is arranged to overlie the base plate 7 when the fastener is in the closed position, and this section 6a is of inverted channel shape having opposed side walls 11 between which a retainer member 12 is mounted for limited pivotal movement on a transverse pivot pin 13 extending between the side walls 11. The upper wall of the handle section 6a is provided with an aperture 14 through which an actuating portion 15 of the retainer 12 protrudes.

The retainer 12 is confined between the side walls 11 and is mounted on the pivot pin 13 with a spring 16 being located in a pocket 1 7 formed in the retainer member to one side of the pivot axis remote from the portion 15 so that the retainer is biassed by the spring into the position shown in Figure 3.

The retainer 12 includes an abutment end 18 which is arranged to protrude from the underside of the handle section 6a to engage within a recessed formation 19 of the base plate 7.

As should now be understood when the retainer 12 is in the position as depicted in Figure 3, the handle assembly 1 is in the closed position, then the abutment end 18 of the retainer 12 is received within the recessed formation 19 and the lever handle 6 cannot be turned about the pivot 8 into the open position for the abutment end 18 is trapped and confined within the recessed formation 19 of the base plate 7.

To release the lever handle for opening movement, the actuating portion 1 5 may be depressed so as to push the retainer on the side opposed to the spring force and to overcome the spring 16 thereby moving the abutment end 18 towards and between the walls 11 out of engagement with the recessed formation 19. Once the retainer 12 has been so moved, then the lever handle 6 is released for opening movement about the pivot 8 relative to the base plate 7. Once the lever handle has been moved to clear the base plate 7, then the actuating portion 15 may be released by the user.

With reference to Figures 4 and 5, there is shown a transverse section through the base plate 7 having the central recessed formation 19 that extends lengthwise of the base plate 7 generally in the same direction as the lever handle 6 when in the closed position. On each lateral side of the base plate 7 adjoining the recessed formation 19, there are provided inclined ramp faces 20. Each of these ramp faces 20 is designed to be engaged by the abutment end 18 of the retainer 12 at the approach to the closing position (whether the handle assembly be mounted for left or right hand operation) so as to displace the abutment end towards and between the two side walls 11 until the abutment end is aligned and in register with the central recessed formation 19 into which it automatically engages under the action of the spring 16.

These two ramp faces 20 are not essential as the lever handle may be brought into the closed position whilst depressing the actuator portion 1 5 to clear the abutment end 18 over the side edges of the base plate 7, but the ramp faces do enable such automatic operation of the retainer to secure the fastener when brought into the closed position.

In the design of the retainer 12 of this embodiment, it should be noted that the retainer has a heel portion 21 remote from the pivot pin 13 and on the same side as the actuating portion 15. This heel portion 21 provides a limit stop for movement of the retainer 12 in an anti-clockwise sense. On the other side of the pivot pin 13, the retainer 12 has an inclined stop face 22 which limits movement of the retainer 12 in a clockwise sense. The abutment end 18 of the retainer 12 may be shaped to complement the recessed formation 19 in the base plate 7 and may have chamfered or rounded edges to assist in a smooth sliding engagement when displaced on the automatic reengagement as just described.

With reference to the alternative embodiment as shown in Figure 6, the invention is shown for the same type of casement fastener as previously described with a similar handle assembly. Accordingly, like parts are given the same reference numerals.

In this alternative embodiment, the retainer 12 is biassed into the position to engage the abutment end 18 with the recessed formation 19 in the base plate 7 by a leaf spring 30.

The leaf spring 30 has one end remote from the pivot pin 13 anchored by a rivet 31 to the underside of the lever handle 6. The free end 30a of the spring 30 is arranged to bear against the underside face 32 of the retainer on the same side of the pivot pin 13 as the actuator portion 15. Accordingly, the spring 30 applies a force to the retainer to hold the retainer in the position shown in Figure 6, and by depressing the actuator portion 15, the spring force may be overcome to displace the abutment end of the retainer 12 in a clockwise sense to release the abutment end from the recess 19.

It is envisaged that the spring bias for the retainer may be provided by a coil spring mounted on the pivot pin 13 and acting on the retainer to bias it in an anti-clockwise direction with the bias being overcome by pressure on the actuating portion of the retainer as just described.

The retainer may be a plastics moulding of suitable light strength and low friction. Although the actuating portion is shown projecting through an aperture in the lever handle, it will be appreciated that the actuating portion could be provided by one or opposed lateral lugs projecting to one or both sides of the lever handle.

The security device provided by the spring loaded retainer and the special recessed formation in the base plate may be applied to casement fasteners of the cockspur or nib kind as the invention merely seeks to prevent relative movement of the lever handle relative to -it's base plate when the lever handle is in the closed position. Thus, the invention can be embodied in a diverse range of casement fasteners as will be understood by those familiar with such window fittings.

Claims (15)

1. A casement fastener of the kind described and wherein the handle assembly comprises a base plate, a lever handle mounted on the base plate by a pivot for pivotal movement between an open position and a closed position, the base plate being provided with a recessed formation for engagement by a retainer when the handle is in the closed position, the retainer comprising a member pivotally mounted on the handle and biassed towards the base plate by spring means, the member having an abutment end extending to one side of the pivot mounting for engagement with the recessed formation and an actuation end extending to the other side of the pivot mounting with the actuation end having a portion accessible to the user whereby, on depressing the portion relative to the lever handle, the abutment is moved in the opposed sense to release the retainer from engagement with the recessed formation of the base plate to permit the lever handle to be moved from the closed position to the open position and, on movement of the lever handle from the open position to the closed position, the spring-loading of the retainer enables the abutment end to be displaced to engage in the recessed formation to hold the lever handle in the closed position.

2. A casement fastener according to Claim 1 wherein the retainer member is mounted on the underside of the lever handle.

3. A casement fastener according to Claim 1 or Claim 2 wherein the lever handle has a section of inverted channel shape in which the retainer member is mounted with the portion of the actuation end of the retainer member protruding through an access opening or aperture formed in the lever handle.

4. A casement fastener according to Claim 3 wherein the pivot mounting extends between the opposed side walls of the inverted channel section and the access opening or aperture is formed in the upper wall of the inverted channel section.

5. A casement fastener according to any one of the preceding Claims wherein the retainer member has a first stop to limit pivotal movement of the retainer member under the biassing of the spring means.

6. A casement fastener,according to Claim 5 wherein the retainer member has a second stop to limit pivotal movement of the retainer member in the opposed sense against the biassing of the spring means.

7. A casement fastener according to any one of the preceding Claims wherein the base plate is co-operable with the abutment end when the lever handle is turned from the open position to the closed position to displace the abutment end to engage automatically in the recessed formation.

8. A casement fastener according to Claim 7 wherein the base plate has at least one lead-in or ramp face adjoining the recessed formation engageable with the abutment end for displacing the abutment end to effect said automatic engagement.

9. A casement fastener according to any one of the preceding Claims wherein the spring means acts between the handle and the abutment end of the retainer member.

10. A casement fastener according to any one of Claims 1 to 8 wherein the spring means acts between the lever handle and the actuation end of the lever handle.

11. A casement fastener according to any one of the preceding Claims wherein the lever handle has a projecting lug, nose or like formation for engagement with the striker in the closed position.

12. A casement fastener according to any one of Claims 1 to 10 wherein the striker has a projecting lug, nose or like formation for engagement with the lever handle in the closed position.

13 A casement fastener according to any one of the preceding Claims wherein the lever handle and striker are adapted to engage to maintain the casement closed or in a partially open vent position.

14. A casement fastener of the kind described substantially as hereinbefore described with reference to Figures 1 to 5 of the accompanying drawings.

15. A casement fastener of the kind described substantially as hereinbefore described with reference to Figures 1 to 5 of the accompanying drawings as modified by Figure 6 of the accompanying drawings.