GB2147941A

GB2147941A - Locking fastener

Info

Publication number: GB2147941A
Application number: GB08425805A
Authority: GB
Inventors: William Tulloch; Richard John Ashmead
Original assignee: Titon Hardware Ltd
Current assignee: Titon Hardware Ltd
Priority date: 1983-10-14
Filing date: 1984-10-12
Publication date: 1985-05-22
Also published as: GB2147941B; GB8425805D0; GB2148383B; GB8327630D0; GB2148383A; GB8425804D0

Abstract

A locking fastener is disclosed e.g. for a door or window comprising a mounting plate 12, a handle 14 pivotally mounted on the plate for movement between a closed and an open position, and a substantially cylindrical locking member 34 captive between the plate and handle (or formations thereon) and having a substantially chordal segment removed therefrom, rotation of the locking member with the handle in the closed position, bringing a part of the member into or out of engagement with the handle or plate (or a formation thereon) respectively to restrict movement of the handle with respect to the plate or allow movement thereof to the open position. <IMAGE>

Description

SPECIFICATION Locking fastener This invention relates to locking fasteners of the type used for locating and securing a window, or door in a closed or partially closed position within a frame.

The particular type of fastener with which the present application concerns itself comprises a base plate usually affixed to the door, or to the casement or sash of a window, and a handle pivotally mounted on the plate for the movement between open and closed positions. Window fasteners of this type, whether for casement or sash windows will usually be provided with a formation on the handle which will, in the closed position, engage the window frame or adjacent sash to prevent movement of the casement with respect to the frame, or of adjacent sashes with respect to one another, and in the open position be in effect retracted from contact with the frame or adjacent sash such that the window may be opened. Door fasteners of this type will usually be provided with means to operate an internal latch/bolt arrangement.In both cases the fastener e.g. may be affixed by its base plate to the door or window frame, but this 'reverse' arrangement is less commonly used.

The invention is particularly relevant to window fasteners, but the equivalence of function to door handles etc will be appreciated. Any references to window handles and catches may therefore be taken likewise as references to door handles etc having equivalent features, and vice versa, unless the context is to the contrary.

Normal such window fasteners operate simply on a pivotal basis and have no means to restrain movement of the handle with respect to the plate. With these it is possible merely by breaking the window for a would-be intruder to move the fastener handle about its pivot relative to the mounting plate and thereby release the window to gain access to the building. In order to prevent, or at least reduce the risk of this a number of arrangements have been proposed to enable the user, for example a householder, to lock the handle with respect to the mounting plate by some form of mechanical engagement. In high security applications a security lock requiring use of a key or perhaps a release combination may be used to enable some sort of mechanical engagement of a formation either on the handle or the plate to engage and disengage from complimentary formation on the plate or handle.Where a lower degree of security is required simpler arrangements have been used, for example having a hidden grub screw, usually located in the handle, which can be screwed by the user into and out of engagement with a recess on the plate with a simple hexagonal section key. Such lower security arrangements are particularly appropriate for use in locations such as high rise residential blocks where it is not intruders which are of concern but the possibility of children being able to open windows and thereby or therethrough to come to harm.

Similar considerations apply to prior art door handles. For some internal uses, the security of e.g. a convential tumblertype key and lock arrangement may be superfluous and provision for lower security locking acceptable.

It is with the lower security type of arrangement that the present invention is particularly concerned. The grub screw arrangement described above suffers a number of disadvantages, particularly cost in so far as accurate machining and threading is required, that higher specific performance materials are needed for the threaded parts of the fastener, and that the necessary displacement of the screw axis from the pivot axis of the handle can with repeated use of the screw arrangement lead to damage to the handle, e.g. by lever forces. It is therefore an object of the present invention to produce a satisfactory locking fastener towards the lower end of the security range which avoids or at least mitigates the disadvantages of the known systems at an acceptable commercial cost.

According to one aspect of the present invention a locking fastener comprises a mounting plate, a handle pivotally mounted on the plate for movement between a closed and an open position, and a substantially cylindrical locking member captive between the plate and handle (or formations thereon) and having a substantially chordal segment removed therefrom, rotation of the locking member with the handle in the closed position bringing a part of the member into or out of engagement with the handle or plate (or a formation thereon) respectively to restrict movement of the handle with respect to the plate or allow movement thereof to the open position.The closed position is that in which the handle or a formation thereon will restrict movement of a casement, sash or door relative to its frame; the open position is that in which the handle is rotated about its pivot so it does not restrict movement of the window or door for opening it.

By the term "captive" is meant that the locking member is retained in position by and in relation to the handle and the plate at all relative positions with respect to one another permitted of the handle and plate during normal operation. The handle and plate may form between them a cavity to hold and locate the locking member, the cavity alone constraining the locking member from movement other than about its axis. This is preferably in the absence of any permanent affixation of the locking member either to the handle or to the plate. However the invention does encompass arrangements where affixation of the locking member to the handle or plate is provided. This may be after assembly of the plate, handle and locking member and may, for example, involve affixing a key or knob to the locking member through a hole in the handle.

In one form of the invention the pivot axis of the handle and the rotational axis of the locking member are substantially parallel. The locking member in this arrangement is preferably held captive in a cavity provided in the underside of the handle (that facing the base plate) and restrained from axial movement by abutment with a surface on the upper side of the plate. The end face of the locking member in abutment with that surface will slide over it when the handle is turned. The cavity in the underside of the handle is preferably segmental in section and has a cylinder radius substantially that ofthe locking member but providing a small clearance between the locking member and the cavity wall.This cavity is preferably a major segment so that when the locking member is in place in it, it is substantially restrained from movement in any direction radial to its axis, save that is as is permitted by the clearance between the locking member and the cavity. This cavity may be provided in a formation on the handle, such as a skirt, extending towards the plate.

The fastener may be a window handle, e.g.

for use on casements, a catch e.g. for use on sash windows, or a door handle.

In another form of the invention the rotational axis of the locking member is substantially tangential to a radius from the axis of the handle pivot. In this form the locking member may be restrained from movement in a direction radial to its axis by e.g. a cavity in the underside of the handle and by abutment with an upper surface of the plate, and from movement in an axial direction by the ends of the cavity in the underside of the handle.

The cavity in the underside of the handle may be of any convenient form to provide the necessary location of the locking member. It may for example be of rectangular section, or in a preferred form be segmental in section, both of course providing a small clearance for the locking member to enable it to rotate about its axis. Where a segmental section cavity is provided it preferably has a chordal length such that the cylindrical locking member may be inserted through the chordal opening into the cavity. If this is not so, then means will have to be provided for the locking member to be inserted, e.g. axially, and the cavity closed around it by appropriate means.

In these forms of the invention, with the axis of the handle pivot and the cylindrical locking member substantially tangential to one another, the locking member may be rotated into or out of the position where it locks the handle to the plate from one or another side of the handle itself, e.g. through a hole through the handle so that it may be rotated by a user by use of an appropriate key.

Engagement of the appropriate part of the locking member to restrict handle movement may be by abutment against a formation on the handle or plate or, in a preferred form of the invention, may be by entering into a recess in the handle or plate. The said recess into which the locking member may extend to lock the handle in the closed position is preferably concave and part cylindrical in planar section, the cylinder radius of the recess being substantially that of the locking member such that it may receive the cylindrical part thereof. The said recess is preferably a minor segment, the major segment being provided as above, the two segments between them forming a cylindrical cavity of radius slightly greater than that of the locking member.The minor segment (the said recess) is preferably provided in the base plate or a formation thereon such as a boss surrounding the handle pivot axis. the major segment (the cavity referred to above) being in the handle or formation thereon. Thus in a particularly preferred form of the invention the plate or a formation thereon and the handle or a formation thereon each have substantially axially extending recesses which, with the handle in the closed position, form between them a substantially cylindrical cavity for the substantially cylindrical locking member. In this case the said recesses are preferably substantially segmental in which either the handle recess or the plate recess may form the major segment to locate the cylindrical member. The axial recesses may be parallel to the handle pivot axis or tangential thereto as is required.

When the axes of the locking member and the handle pivot are tangential the major recess is preferably in the handle or a formation thereon, and the minor recess/segment on the plate or e.g. a boss surrounding the handle pivot. The segment removed from the locking member may be such as leaves a concave recess, part cylindrical in planar section. Thus the terms "segment" and "segmental" when used herein relate to the minimum cross-section area removed from a cylinder of constant radius. A greater cross-section area may be removed, for example to leave a concave recess as defined above without departing from the intended scope of the invention. Forming the locking member in effect by extension of the recess into the major segment of its cylinder of constant radius is therefore a part of the invention. This of of particular relevance to an arrangement where the locking member and handle pivot axes are parallel, and if in this the segment removed from the cylindrical member leaves a concave recess part cylindrical in planar section, the cylinder radius of that recess is preferably substantially that of the handle or pivot, or plate or formation thereon in each case to allow clearance therebetween such that the handle may be moved in relation to the plate.

The present invention may be put into practice in various ways and specific embodiments will now be described by way of example with reference to the accompanying drawings in which: FIGURE 1 is plan view of a typical fastener according to the invention; FIGURE 2 is a section of the fastener of Figure 1 along line A-A, FIGURES 3 and 4 are reverse views of a fastener as shown in Figure 1 (save in that they are of the reverse hand) showing the operation of the locking arrangement, FIGURE 5 is a section of a further fastener according to the present invention, FIGURE 6 is a section of a still further fastener according to the present invention, FIGURE 7 shows an expanded sectional view of a cylindrical locking member and its recesses as may be used in the various fasteners embodying the invention, and FIGURE 8 shows a further partial view of the handle of Figure 6 from point of view B but with the base plate removed.

Referring to the drawings there is shown at Figure 1 a locking window fastener 10 comprising a mounting plate 1 2 and a handle 1 4.

The handle 14 is pivotally mounted to the mounting plate 1 2 through its pivot 1 6 and appropriate known securement means 1 8.

The handle is provided with a snib or catchpiece 20 arranged to cooperate with a striker plate mounted on the frame when the fastener is mounted on the window casement or viceversa. When the handle 14 is rotated about its pivot 1 6 in an anti-clockwise sense as shown in Figure 1 the snib or catchpiece 20 will rotate away from the position where it engages its associated keeper thus allowing the window casement to be moved freely in relation to its frame, The mounting plate 1 2 is provided with screw holes 22 for affixation of the mounting plate 1 2 to the window casement or frame. The means of affixation may of course be varied in any conventional manner.

The mounting plate 1 2 is also provided with a boss 24 which surrounds and is substantially coaxial with the handle pivot 16.

Referring now to Figure 3 there will be seen a concave recess 26 extending substantially axially along the periphery of the boss 24.

The handle 1 4 is provided with a skirt 28 which depends from the handle towards the mounting plate 12. In the skirt 28 is a part cylindrical recess 30. The recesses 26 and 30 between them with the handle in the position shown in the figures provide a substantially cylindrical cavity 32 of substantially circular cross-sectional area. The recess 26 provides the minor segment and the recess 30 provides the major segment of the circle. Located within the cavity 32 is a cylindrical plug 34 of substantially circular section save in that a segment has been removed therefrom leaving a concave, part cylindrical surface 36. The plug 34 has an overall radius a little less than that of the cavity 32 such that it is located within the cavity 32 and may rotate therein.

The radius of the surface 36 is substantially that of the boss 24. Reference is made now particularly to Figure 4 where it can be seen that the concavity 36 in the plug 34 is arranged such that it forms a substantially continuous inner circumferential surface with the inner surface 38 of the skirt 28. With the plug 34 in this position the handle 14 may rotate freely about the pivot 1 6 and the boss 24 of the mounting plate 1 2. When the plug 34 is rotated through 180 to the position shown in Figure 3 it will be seen (subject to slight exaggerated clearances in the drawings) that the surface of the plug 34 nestles into the recess 26 on the boss 24 and thereby prevents rotation of the handle 14 relative to the mounting plate 1 2.

The recess 30 is of substantially the axial length of the plug 34. The inner end of the plug 34 abuts the plate 1 2 and is therefore held captive by the recess 30 and the plate 12.

The handle 14 is provided with a key hole 40 through which an appropriately shaped key may be passed to engage a key slot (not shown) in the plug 34. The key hole 40 and the appropriate key are of the "two wing" type such that the key may only be inserted into the key hole 40 and the key slot in the plug 34 and removed therefrom at positions 180 apart. Stops or other guides may if necessary be provided between the plug 34 and the cavity 32 such that the plug may not jam in a position between the two 180 positions.

In alternate embodiments (not shown) the recess 26 may provide the major segment of the cavity 32 and the skirt 28 provide the minor segment in which case the plug 34 would be located and held within the major segment in the boss rather than as shown.

Referring now to Figure 5 there is shown a view corresponding to that of Figure 2 but of a further fastener of the present invention.

When numerals are used as before they identify the same item or feature of the fastener. It will be seen that there is a recess 26' in the periphery of the boss 24 extending generally tangentially thereof, the recess 26' being concave and part cylindrical in cross-section.

There is a recess 30' provided in the skirt part 28 of the handle, the recess 30' again being part cylindrical in cross-section and again having its cylinder axis substantially tangential to the axis of the pivot 1 6 of the handle 1 4. The two recesses 26' and 30' between them form a cylindrical cavity within which is received a cylindrical plug 34' from which a minor segment has been removed. The plug 34' is of cylinder radius slightly less than the cavity but otherwise of comparable dimensions so that it fits entirely within the cavity for rotation, with the handle in the position shown in Figure 5.

Rotation of the plug 34' about is cylinder axis will bring the cylindrical part of the plug 34' into the recess 26' when the handle 1 4 is in the closed position relative to the plate 1 2 thereby locking the handle 14 to the plate 12.

Access to the plug 34 may be from one side of the handle or either side by use of an appropriate key (not shown).

FIGURE 6 shows a further fastener according to the present invention corresponding to the fastener shown in Figure 5 save in that the cylindrical plug 34" is contained in a recess 30" which opens out not against the boss 24 but against the base of the mounting plate itself 1 2. In that base there is provided at 26" a part cylindrical recess corresponding to 26". The function of the fastener, notably by rotation of the cylindrical plug 34", is otherwise equivalent to that described in relation to Figure 5.

Figure 7 shows an expanded view of an alternative recess 30/30'/30" and plug 34/34'/34" arrangement which may be used with any of the embodiments described hereto. It will be seen that the plug 34 and recess 26 are substantially as previously shown. However the recess 30 is shown as substantially rectangular in section. This arrangement will be particularly beneficial with the fastener shown in Figures 5 and 6 as the recesses 30'/30" may be cut into the skirt 28 of the handle leaving material at either end to hold the plug 34 captive. An example of this is shown in Figure 8 this being relevant particularly to the fastener of Figure 6.In assembly of fasteners of Figure 5 and 6 the cylinder 34 is simply placed into the closed channel 30 as shown in Figure 8 and then the handle 14 assembled to the base plate 1 2. A key hole shown in chain lines at 40 is provided for rotation of the plug 34.

If a recess 30 of segmental form as shown in Figures 5 and 6 is required it is preferred that the ratio of segments provided by the recesses 26 and 30 is such that the chordal length dividing them permits the plug 34 to be inserted in the recess 30 through the chordal opening so that a closed channel 30 in the manner shown in Figure 8 may be provided. If this is not the case it will be necessary to have a detached element of the handle or skirt e.g. adjacent the key entry hole 40 so that the plug 34 may be inserted axially into the recess 30 and the recess then closed about it.

It is believed that the present invention has considerable benefits not least of which are ease of operation and simplicity of function.

However a prime advantage is believed to be in the manufacturing as it is expected that all or substantially all of the parts may be cast in aluminium or other suitable material, that to include the plug and the key such that if casting is done to appropriate tolerances the assembly of the fastener will actually require only the normal operations of assembly of a fastener plus the operation of inserting the cylindrical plug member 34. Thus in comparison to the grub screw arrangement described earlier manufacturing processes and therefore cost are expected to be reduced substantially particularly as lesser quantities of higher performance materials are required and no drilling or tapping operation is expected to be needed.

The present invention relates to any feature or any combinations of features described herein.

Claims

1. A locking fastener comprising a mounting plate, a handle pivotally mounted on the plate for movement between a closed and an open position, and a substantially cylindrical locking member captive between the plate and handle (or formations thereon) and having a substantially chordal segment removed therefrom, rotation of the locking member with the handle in the closed position bringing a part of the member into or out of engagement with the handle or plate (or a formation thereon) respectively to restrict movement of the handle with respect to the plate or allow movement thereof to the open position.

2. A fastener as claimed in Claim 1 wherein rotation of the locking member with the handle in the closed position brings a part of the member into or out of a recess in the handle or plate (or a formation thereon) respectively to restrict movement of the handle with respect to the plate or allow movement thereof to the open position.

3. A fastener as claimed in Claim 2 wherein the said recess is in the handle or pivot thereof.

4. A fastener as claimed in Claim 2 wherein the said recess is in the plate or a formation thereon.

5. A fastener as claimed in Claim 3 wherein the said recess is in a boss surrounding the handle pivot.

6. A fastener as claimed in any of the preceding claims wherein the handle has a formation thereon extending towards the plate and providing a cavity to locate the locking member.

7. A fastener as claimed in Claim 6 wherein at least a part of the base of the said cavity is provided by the plate.

8. A fastener as claimed in any of the preceding claims wherein access is provided through the handle for means for rotation of the locking member.

9. A fastener as claimed in Claim 9 wherein the said means for rotation is a removable key.

10. A fastener as claimed in Claim 9 wherein the said means for rotation is affixed to the locking member.

11. A fastener as claimed in any of the preceding claims in which the axes of the handle pivot and the locking member are substantially parallel to one another.

1 2. A fastener as claimed in any of Claims 1 to 11 in which the axes of the handle pivot and the locking member are substantially tangential to one another.

1 3. A fastener as claimed in any of Claims 2 to 1 2 wherein the said recess is concave and part cylindrical in planar section, the cylinder radius being substantially that of the locking member, such that it may receive the cylindrical part of the locking member.

1 4. A fastener as claimed in any of the preceding claims wherein the segment removed from the cylindrical member leaves a concave recess, part cylindrical in planar section.

1 5. A fastener as claimed in any of the preceding claims wherein the plate or a formation thereon and the handle or a formation thereon with the handle in the closed position, form between them a substantially cylindrical cavity for the substantially cylindrical locking member.

1 6. A fastener as claimed in Claim 1 5 in which the said substantially cylindrical cavity is formed from a recess or recesses in the plate or formation thereon and/or the handle or formation thereon.

1 7. A fastener as claimed in Claim 16 wherein the said recesses are substantially segmental.

18. A fastener as claimed in Claim 1 7 in which the handle recess forms the major segment of the said cavity to locate the locking member.

1 9. A fastener as claimed in Claim 1 7 in which the plate recess forms the major segment of the said cavity to locate the locking member.

20. A locking fastener substantially as described herein with reference to any of the accompanying drawings.