GB2216592A - Casement fastener - Google Patents

Abstract

A casement fastener comprises a handle 1 pivotally mounted on a base plate 2 by means of a screw-threaded tubular boss 11 which projects forwardly from the base plate and engages within a tapped bore 6 in the body of the handle 1. The handle 1 is fabricated as an extrusion or forging, and is formed with a square section transversely-extending recess 7 into which opens the inner end of bore 6. Recess 7 receives and operatively engages the end of a square section operating spindle 8 threaded through the boss 11. The boss 11 is provided by a separate injection moulded or cast insert part 10 fitted in the hollow interior of the base plate 2 which is of extruded channel section. Reference is also made to an alternative form in which the boss 11 is formed integrally with the base plate. <IMAGE>

Description

CASEMENT FASTENER This invention relates to casement fasteners in which an operating member, such as for example a lever handle, is pivotally mounted for angular movement on a separate base member. The base member of such casement fasteners generally comprises a plate-like member, i.e. a base plate, that is fixed in use to a frame part or profile of the casement window or door in connection with which the fastener is used, and the invention is particularly concerned with casement fasteners of this kind wherein it may be desired to fabricate the operating member as an extrusion or forging and wherein the base member or base plate may need to have an elongate form with a relatively narrow width.

In casement fasteners of this kind the operating member or handle is commonly required to connect to an operating spindle of non-circular or non-round crosssection, as for example a square cross-section, and this spindle may need to have different lengths to suit different installations and window profiles of various thickesses. However, many known arrangements for assembling operating members such as lever handles, especially where it is necessary to accommodate and retain an operating spindle of square or other noncircular cross-section, have required the use of wide base plates and/or complicated and costly spindle retaining means and securing means for mounting the operating member on the base member.

Some casement fasteners commonly available which incorporate lever handles made from extruded material and which are designed to enable operating spindles of any required length to be inserted to suit window profiles of various thicknesses have extruded legs on that face of the lever handle which, in the completed assembly, rotates against a surface of the base plate. In this particular known form of construction, these legs are spaced apart to permit entry of a square section spindle into a blind hole drilled in the body of the lever handle, and in preparation for assembly of these devices the legs are machined by hollow milling or turning to provide a bifurcated cylindrical boss adapted for entry into a prepared cylindrical hole in the base plate such that this boss then acts as a pivot.The lever handle is then retained in its assembled position and is secured to the base plate by peening or spinning the extremities of these legs over a retaining washer on the underside of the base plate. However, this method of securing to the base plate requires that sufficient material be outwardly displaced in the manner of a rivet to securely retain the handle to the base, and this severely limits the minimum width of the base plate since this width must be sufficient not only to accommodate the spindle but also to allow for the space taken up by the material upset by the peening or swaging operation. This can be a serious limitation since the dimensions of profiles of modern windows, particularly those made from extruded plastics, demand narrow base plates, e.g. 16mm maximum width, in most instances.

In the above-described known construction, the operating spindle is moreover usually machined to provide a cylindrical portion having splines at the outer end which is driven into the blind hole drilled in the lever handle, or alternatively a transverse hole is drilled in that portion which enters into the body of the lever handle in order to receive a retaining pin inserted, via a drilled hole in the lever handle, to prevent the spindle from turning relative to the handle. During assembly, it is not easy to line up the holes if they are pre-formed and the alternative of drilling through the handle to penetrate a round comparatively hard surface of the spindle can be a difficult and time consuming operation likely to increase the cost of production.

It is accordingly an object of the present invention to provide a construction of casement fastener which includes improved assembly means especially suitable for use with operating members or handles that are fabricated as extrusions or forgings and which can enable base members of narrow width to be used whilst still permitting conventional sizes of non-circular or square cross-section operating spindles of various lengths to be fitted and operatively connected to the operating member or handle component.

More particularly, the present invention provides a casement fastener of the kind in which an operating member, such as for example a lever handle, is pivotally mounted for angular movement on a separate base member, characterised in that said base member includes a forwardly projecting boss formed with an external screw thread which engages within a complementary screw threaded bore or recess in said operating member to provide a pivot mounting for the latter.

The forwardly projecting screw-threaded boss may be formed by part of a separate insert member housed within a hollow interior of the base member in which case this forwardly projecting screw threaded boss may project through an aperture in the front of the base member and the latter may comprise an extruded channel section base plate. Alternatively, the forwardly projecting boss may be integrally formed with the base member.

In preferred embodiments, for accommodating a fastener operating spindle, the forwardly projecting boss is of tubular form with a through bore providing an axially extending passageway for the spindle; also, the inner end of the screw threaded bore or recess in the operating member may open into a cavity formed by a recess, preferably a transversely extending recess, of non-circular cross-section which is adapted operatively to engage an outer end portion of the operating spindle which also has a non-circular cross section.

By means of the present invention, the operating member or handle is retained upon the base member in such a manner as to be able to withstand the operating forces to be met when, for example, used with a spindle to operate an espagnolette bolt or, alternatively, when used with a wedge or striking plate as a face-fixed fastener, whilst at the same time the width of the base member can be kept to a minimum and the operating member or handle itself can conveniently be fabricated as an extrusion or forging.

Further features and advantages of the invention will become apparent from the following description, presented by way of example, of a particular embodiment of the invention illustrated in the accompanying drawings. In these drawings: FIGURE 1 is a general perspective view of a casement fastener in accordance with the invention comprising a fastener operating handle assembly shown mounted on a window casement or door leaf; FIGURE 2 is an exploded perspective view of the casement fastener of this particular embodiment of the invention showing the components of the assembly; and FIGURE 2a is a fragmentary cross-sectional view of the lever type operating handle of this assembly, at the position indicated, showing the operating spindle entered into its retaining recess.

Referring to the drawings, there is shown a casement fastener comprising a first part being an operating lever handle 1 mounted on a second part or base member comprising a base plate 2 for pivotal movement about a pivot through which the two parts are secured together.

The base plate 2 is provided with countersunk holes 3 to receive fixing screws by which it is mounted onto the stile of a window sash frame plate. The casement fastener is arranged to receive a non-round, e.g. square section, spindle 8 by means of which a bolting mechanism (not shown) is operated. In the handle 1 is a tapped screw-threaded recess 6 which opens onto an extruded square sided recess 7 into which the end of the square spindle 8 is received in such a manner that it is turned as the lever handle 1 is turned. A resilient wavy thrust washer 9 is fitted to retain tension between the handle 1 and the base plate 2, and the latter is formed by an extruded hollow channel section into the open ends of which are inserted two identical plastic injection mouldings 5 having through holes 3A that coincide with the countersunk holes 3 on the base plate 2.Within the hollow interior of the base plate 2 is fitted a separate insert member 10, seen here as an injection moulding or a diecasting, having a threaded boss 11 and a round throughhole or bore 12 providing an axial passageway through which the spindle 8 extends. Insert member 10 has recesses 13 on both sides to receive and retain under tension leaf springs 15. At the mid-points of the bases of these recesses 13 are openings 14 through which portions of the leaf springs 15 have access to the flat sides of spindle 8 within the bore 12.

The components are assembled in the following manner. Leaf springs 15 are placed under slight tension into the recesses 13. The sub-assembly of the insert member 10 and springs 15 is then inserted into the base plate 2 in the direction of the thick arrow "A" so as to pass through a pivot hole (not shown) in the front face of the base plate 2. Wavy washer 9 is placed on the boss 11 which is then entered into the screw-threaded hole 6 in the lever handle 1. The lever handle is screwed over the boss until the wavy washer 9 is gripped with sufficient force to permit rotation with the lever and base plate lined up in the locked position of the fastener. Spindle 8 is then urged through hole 12 in member 10 until its outer end projects into and is secured within extruded recess 7 in the lever handle.

Plastic end caps 5 are finally inserted into the open ends of extruded base plate 2.

The leaf springs 15 have a dual role in that they hold the spindle securely against dislodgement by slamming and they also provide a positive click stop on rotation of the spindle between locked and unlocked positions of the fastener.

The invention is not limited to the embodiment of the casement fastener operating handle above described.

In another embodiment for example, for use as a facefixed fastener the fastener handle may be provided with a lug or tongue to engage against a wedge plate or keeper and, in this case, the spindle may be omitted.

The fastener assembly may also be formed with a gap between the handle and the base plate to receive a wedge and a recess may be provided in the side faces of the handle to engage such wedge whilst the fastener is in a partly open position, e.g. in a night ventilation position. Also, as previously indicated, the threaded boss 11 may be formed integral with the base plate 2, especially if the latter is made as a cast or moulded base plate.

Claims (14)

1. A casement fastener of the kind in which an operating member, such as for example a lever handle, is pivotally mounted for angular movement on a separate base member, characterised in that said base member includes a forwardly projecting boss formed with an external screw thread which engages within a complementary screw threaded bore or recess in said operating member to provide a pivot mounting for the latter.

2. A casement fastener as claimed in Claim 1 wherein the base member has a hollow interior formed by an extruded channel section base plate and the forwardly projecting boss is formed by part of a separate insert member that is housed within said hollow interior of the base member.

3. A casement fastener as claimed in Claim 2, wherein the separate insert member including the forwardly projecting screw-threaded boss is a one-piece moulded body.

4. A casement fastener as claimed in Claim 3, wherein the separate insert member is composed of moulded plastics material.

5. A casement fastener as claimed in any of Claims 2 to 4, wherein the forwardly projecting screw-threaded boss projects through an aperture in the front of the base member and said insert member is located between separate end caps fitted into opposite ends of the channel section base plate.

6. A casement fastener as claimed in Claim 1 wherein the forwardly projecting boss is integrally formed with the base member.

7. A casement fastener as claimed in any of the preceding claims wherein the forwardly projecting boss is of tubular form with a through bore providing an axiallyextending passageway for accommodating a fastener operating spindle.

8. A casement fastener as claimed in Claim 7, wherein the inner end of the screw-threaded bore or recess in the operating member opens into a cavity adapted operatively to engage an outer end portion having a non-circular cross-section of said operating spindle.

9. A casement fastener as claimed in Claim 8, wherein said cavity is formed by a recess of non-circular crosssection extending transversely of the screw-threaded bore or recess in the operating member.

10. A casement fastener as claimed in any of Claims 7 to 9, wherein the base member is provided with at least one spring element adapted to bear against flat faces of said operating spindle thereby to provide a positive retaining pressure effective in use to restrain angular movement of the operating spindle when set in respective open and closed positions of the fastener.

11. A casement fastener as claimed in Claim 10 insofar as it depends from any one of Claims 2 to 5, wherein said at least one spring element is a leaf spring element accommodated in a recess in said separate insert member.

12. A casement fastener as claimed in any of the preceding claims wherein the forwardly projecting screwthreaded boss is fitted with a resilient axial thrust washer arranged to be interposed between the front face of the base member and an opposed surface of the operating member.

13. A casement fastener as claimed in any of the preceding claims wherein the fastener operating member is fabricated as an extrusion or forging.

14. A casement fastener substantially as herein described and illustrated with reference to the accompanying drawings.