GB2076455A - Lockable window fastener - Google Patents

Abstract

A window fastener comprises a handle 10 pivotally mounted on a mounting plate 18 and a locking bolt 20 located slidably in either the plate or the handle. The locking bolt may be a trigger grip arrangement located in the handle for linear movement in a direction substantially parallel to the pivot axis, there being a recess in the facing surface of the mounting plate to receive a distal end of the bolt to locate the handle in its fastening position. <IMAGE>

Description

SPECIFICATION Window securement fastener This invention relates to window securement latches or casement fasteners of the type for locating and securing or locking a window casement in a closed or partially closed position within a window frame within which the casement is located.

The particular type of fastener with which the present application concerns itself is one which will provide a degree of security against intrusion by provision of an element to enable the fastener to be located positively in position, but without incurring the additional expense and complexity of using a security type lock requiring the use of a separate key. With conventional fasteners it is possible merely by breaking a small area of the window around the lock for the would-be intruder to pivot the fastener handle relative to its mounting plate and the window casement and thereby to gain an access to the building. The provision of the element to provide positive location of the fastener makes the task of the would-be intruder more complex in the sense that it is first necessary to release the positive location before pivoting the handle relative to its plate and the casement.

According to the present invention a window securement fastener comprises a mounting plate, a handle pivotally mounted on the plate and a catchpiece located slidably in either the plate or the handle for linear movement into and out of a position where it restricts pivotal movement of the handle with respect to the plate by engagement with the other of the plate or the handle, or with a complementary formation thereon.The catchpiece is preferably located in the handle for linear movement in a direction substantially parallel to the pivot axis of the handle, there being a recess in the facing surface of the mounting plate to receive the distal end of the catchpiece positively to locate the handle and the mounting plate to one another, the position of the recess being such that the end of the catchpiece reaches it when the fastener is in position to secure the casement closed in its frame.

The catchpiece is preferably spring biased towards engagement e.g.with the mounting plate when it is located on the handle. The catchpiece is preferably provided with a trigger type finger grip for convenient manual operation by pulling the catchpiece against its spring bias to release it from positive location e.g. with the base plate.

The mounting plate may be of conventional form for attachment to wood or metal window casements or indeed to equivalent arrangements such as cupboard doors or the like where a similar degree of securement may be required, the mounting plate being provided as necessary with means for affixation to the wood or the metal, e.g.

with appropriately positioned screw holes. The handle should be attached to the mounting plate by a pivot, pin or the like in a permanent fashion there being, if desired, means for adjustment of the friction between the two.

The invention may be performed in various ways and a specific embodiment will now be described with reference to the accompanying drawings in which: Figure 1 is a profile view partly in section of a fastener embodying the present invention; and Figure 2 shows the catchpiece element of the handle of Figure 1 in more detaii.

Referring to the drawings there is shown a handle 10 attached over a pivot element 12 to a mounting plate 18 which mounting plate is constructed to be attached to a window casement by any appropriate means. The handle 10 has a cavity 14 machined into it to receive the catchpiece or bolt element 20. The bolt 20 has a cylindrical section 22 of external diameter approaching that of the internal diameter of the cavity 14, the cavity 14 being axially longer than the bolt section 22.

A recess 24 is provided axially within the section 22 to receive a compression spring 26, the other end of which spring 26 will bear against the wall 16 of the cavity 14 to bias the bolt 20 towards the mounting plate 1 8. At the other end of the section 22 there is provided a force fit stainless steel pin permanently located to protrude beyond the end of the cylindrical section 22. The body of the bolt 20 comprising the cylindrical element 22 and a finger trigger element 28 are preferably molded in a plastics material such as that available under the trade mark DELRIN, the molding either being about the spring 26 and metal pin 27 are not, the spring and pin being fitted subsequently.

When the mounting plate 1 8 is affixed to the casement of a window the window may be held in a closed position relative to its frame by engagement of an element of the handle not shown with a locating plate, also not shown, secured to the window frame, the window being releasable for opening by pivoting the handle 10 relative to the mounting plate 1 8 to take it out of engagement with the complementary plate on the window frame.

When the fastener is in the secured position i.e.

the position in which it holds the window in a closed position relative to its frame, the metal pin 27 of the bolt 20 locates in a recess 19 in the mounting plate 18, the recess 19 being approximately equal in internal dimensions to the external dimensions of the pin 27 so that a secure fit is obtained. The spring bias of the spring 26 will maintain the pin 27 within the recess 1 9 until such time as manual pressure is applied to the trigger piece 28 of the bolt 20 to remove it therefrom.

Means are also provided (not shown) to restrain the bolt 20 from being forced entirely out of the handle 10 by the spring 26 when the distal end of the bolt 20 is removed clear of the mounting plate 18 by pivotal movement of the handle relative thereto.

The handle 10 and the mounting plate 1 8 are preferably of a metallic material such as aluminium.

Claims (9)

1. A window securement fastener comprising a mounting plate, a handle pivotally mounted on the plate and a catchpiece located slidably in either the plate or the handle for linear movement into and out of a position where it restricts pivotal movements of the handle with respect to the plate by engagement with the other of the plate or the handle, or with a complementary formation thereon.

2. A fastener as claimed in Claim 1 wherein the catchpiece is located in the handle for linear movement in a direction substantially parallel to the pivot axis of the handle.

3. A fastener as claimed in Claim 2 wherein a recess is provided in the surface of the mounting plate facing the handle to receive the distal end of the catchpiece.

4. A fastener as claimed in Claim 3 wherein the recess is in a position on the mounting plate such that the distal end of the catchpiece reaches it when the fastener is in a position to secure the casement of a window to which it is attached closed in its frame.

5. A fastener as claimed in any of the preceding claims wherein the catchpiece is biased towards said engagement.

6. A fastener as claimed in any of Claims 2-5 wherein the catchpiece is provided with a trigger grip.

7. A fastener as claimed in any of the preceding claims wherein the catchpiece comprises a moulded plastic body and a metallic pin as the distal end thereof.

8. A fastener as claimed in any of the preceding claims wherein the catchpiece is captive when not in said engagement.

9. A window securement fastener substantially as described herein with reference to the accompanying drawings.