GB2297796A

GB2297796A - Actuating means with locking mechanism for cremone latch

Info

Publication number: GB2297796A
Application number: GB9602477A
Authority: GB
Inventors: Charles Richard Boughton
Original assignee: Archibald Kenrick and Sons Ltd
Current assignee: Archibald Kenrick and Sons Ltd
Priority date: 1995-02-09
Filing date: 1996-02-07
Publication date: 1996-08-14
Anticipated expiration: 2016-02-07
Also published as: GB9602477D0; GB2297796B; GB9502526D0; GB2297796C

Abstract

This invention relates to a locking mechanism (410) and arrangement and to an actuating means with locking mechanism (10). The invention is particularly suitable for locking a panel (2) against movement relative to its fixed (outer) frame (6). The locking mechanism (410) includes an operating member (424) and bolt means (430) mounted to move with the operating member in which the bolt means is mounted to slide relative to the operating member. The actuating means with a locking mechanism (10) has at least one operating member (24a,b) and bolt means (30a,b) cooperating with the said operating member, the bolt means having a free end (34a,b), the bolt means having a first position and an second position, characterised in that the free end projects further from the actuating means in the second position than in the first position.

Description

LOCKING MECHANISM AND ARRANGEMENT, AND ACTUATING MEANS WITH LOCKING MECHANISM FIELD OF THE INVENTION This invention relates to a locking mechanism and arrangement and to an actuating means with locking mechanism. The invention is particularly suitable for locking a panel against movement relative to its fixed (outer) frame.

BACKGROUND TO THE INVENTION The following description and disclosure is for convenience directed to top-hinged sash (opening casement) windows, though it will be understood that the invention is equally applicable to side-mounted sash windows, to other hinged panels such as doors, and to sliding panels such as patio windows or doors.

A sash needs to have a closed condition in which only a small air gap exists between itself and the surrounding frame. Furthermore, a lock means is needed which can secure the sash in the closed condition.

The sash can be held to the frame at one position (single point locking) or at more than one position (multi-point locking). A common locking mechanism can be used to operate multi-point locks simultaneously.

Concurrent with the development of improved locking arrangements has been the introduction of sash frames of aluminium and plastics, which can be formed from long extruded lengths of largely-hollow profile, with some flexibility. It is increasingly a requirement for locking mechanisms to fit within one or other of the hollow chambers of such a profile, positioned so that when the mechanism is operated only a locking tip projects across the air gap to engage within or behind a fixed keeper.

In general therefore it has been recognised for many years that an improved locking mechanism and arrangement is required for movable panels. For sash windows in particular many of the traditional locking mechanisms and/or arrangements have proved ineffective at preventing or siqxlificantly delaying entry by experienced house breakers and the like, who can often quietly open the sash after having created an increased air gap (between the sash and outer fixed frame) with a known jemmy tool, specifically without need to break the glass.

One known locking arrangement utilises a lever (cockspur) mounted so that it can be pivoted into the sash profile i.e. into the so-called sash lock frame part. In use the sash is closed before the cockspur tip is swung out of the profile and into the locking condition; an enlarged air gap between the sash frame and outer fixed window frame is not therefore needed. One disadvantage however of a cockspur is that it is relatively weak in tension, and thus less able to withstand "jemmy" forces towards the sash hinges.Another disadvantage is that for efficient operation the keeper needs to be accurately positioned relative to the cockspur, and to remain so despite possible window distortion or sash hinge loosening; the cockspur needs to swing fully home behind the keeper, not least to reduce the possibility of the cockspur tip, mounted in cantilever, being broken off during unauthorised forced window opening.

A modified cockspur is shown in GB 2,234,545, seeking additionally to overcome the above-mentioned "jemmy" problem.

An alternative, multi-point, locking arrangement is a "cremone", utilising shoot bolts oppositely and simultaneously movable into locking engagement with respective opposed keepers in sash frame connecting parts.

The shoot bolt tips can be withdrawn into a non-locking condition within the sash profile, so that an enlarged air gap is not needed for window closure; in use the sash is closed before the shoot bolts are moved to their "extended" or locking condition.

A multi-point locking mechanism utilising a combination cremone and cockspur is known for instance from GB 2,101,667. One disadvantage of the combination cremone and cockspur is that the sash lock frame part may be forced away from the cockspur keeper, releasing the cockspur from the keeper; continued forcing movement can perhaps then bend the shoot bolts sufficiently to release them from their respective keepers, noted for those larger sash windows which have long shoot bolts and flexible profiles.

DISCLOSURE OF THE PRIOR ART There has long been known an alternative locking arrangement of a projecting bolt, usually a plurality of bolts with a common actuator, which can be used as required in both single and multi-point locking assemblies.

However, because the bolts project permanently from the sash lock frame part, it has been necessary for an enlarged air gap to be present between that frame part and the adjacent window frame part to allow sash closure, and this gap may readily be utilised for the unauthorised insertion of a jemmy or other house breaking tool.

An "espagnolette", for multi-point locking, comprising a number of projecting bolts carried by a slide plate is disclosed in GB 1,504,812 and GB 2,072,740. A handle operates a locking mechanism comprising a slide plate in a closure direction whereby first to bring the bolts into an alignment position alongside a respective opening in a keeper, with further movement in this direction being possible after window closure whereby to effect locking. A disadvantage of such an arrangement is that the slide plate has to be manouvered into the alignment position before the window can be fully closed.

Anti-jemmy (headed) bolt arrangements using an undercut keeper are shown in GB 2,161,208.

Mounting a part of the actuating means for an espagnolette in a chamber of a hollow sash profile is known from GB 2,130,628.

FR-A-2,598,456 utilises two flat bolts with locking teeth which when moved longitudinally to the locking position are forced to move transversely so that the locking teeth project from the closure.

STATEMENT OF THE INVENTION We seek to provide a locking mechanism and arrangement which avoids or reduces the disadvantages outlined above.

In one aspect we provide a locking mechanism which includes an operating member and a bolt mounted to move with the operating member characterised in that the bolt is mounted to slide relative to the operating member.

In another aspect we provide a locking mechanism which includes an operating member movable in a first direction and a bolt mounted to be moved by the operating member in said first direction characterised by guide means for the bolt adapted to move the bolt at an angle to said first direction during said bolt movement.

Preferably the bolt is located in a housing, and the guide means is carried by or integral with the housing; thus the housing can itself be located in a sash profile. In an alternative embodiment the guide means is carried by or integral with the sash profile.

We also provide a locking mechanism having a housing, an operating member partly enclosed within the housing, and bolt means drivingly engaged with the operating member, the bolt means having a free end, the free end having a first position and a second position, characterised in that the free end projects further from the operating member and from the housing in the said second position than in the said first position.

The bolt has a longitudinal axis leading to the free end.

Preferably the free end is enlarged so as to cooperate with an undercut in a keeper, whereby to resist jemmy forces parallel to the bolt longitudinal axis.

Desirably the path of movement of the enlarged portion between the said first and second positions is linear.

Linear movement of the bolt means has an advantage over pivoting movement in that it is easier to position a keeper to engage correctly with the bolt means, and the arrangement is more tolerant to manufacturing and fitting variations.

Usefully, the second position corresponds to the locking condition and the first position corresponds to the unlocking condition. Alternatively, the bolt means has a third position which corresponds to the locking condition, the second position in this case being intermediate between the first and third positions. Desirably, movement of the bolt means between its second and third positions is linear and substantially parallel to the said first direction of the operating member. This latter feature has the advantage that the enlarged portion of the bolt means can be of significant size, and the effective area of that portion in engagement with an undercut area of a keeper is thereby increased.

Usefully, the bolt means is of T-section; usefully also the bolt means carries angled guide means which cooperate with angled channel means of the. housing. Preferably, the angle of the guide means and channel means to the path of movement of the operating member is 450; desirably this angle is between 40 and 500; usefully this angle is between 30 and 600.

Desirably, the guide means and channel means comprise a plurality of separate guide and channel members respectively, to increase the area of sliding engagement between the guide means and channel means and so increase the durability of these means.

Preferably, the bolt means is slidable relative to the operating member in a second direction substantially perpendicular to the first direction of the operating member.

We also provide an actuating means with a locking mechanism, the actuating means having at least one operating member and bolt means cooperating with the said operating member, the bolt means having a locking tip, the bolt means having a first position and an second position, characterised in that the locking tip projects further from the actuating means in the second position than in the first position. Usefully the locking tip is laterally enlarged, whereby to fit beneath a keeper undercut.

There is also provided a locking arrangement for a movable panel in a fixed frame in which the panel carries cremone actuating means and two shoot bolts, the cremone actuating means having two operating members, each operating member being connected to a respective shoot bolt, characterised in that each operating member cooperates with a slidable bolt means. Preferably, each of the said bolt means has an enlarged portion, and each bolt means has a first position and a second position, the enlarged portion of the bolt means projecting further from the actuating means in the second position than in the first position, and in that the bolt means in its second position is engageable with a keeper mounted to the fixed frame.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described, by way of example, with reference to the accompanying drawings (not to scale), in which: Fig.l is a front view of a sash window in a fixed outer frame, the window having a cremone actuating means with locking mechanism according to the invention; Fig.2 is a sectional view through the window and frame of Fig.l; Fig.3 is a perspective view of an actuating means with two locking mechanisms, each bolt means being in the first or unlocking condition; Fig.4 is a view as Fig.l, each bolt means being in the third or locking condition:: Fig.5 is a perspective view of a keeper for use with the actuating means of Figs. 3 and 4; Fig.6 is an end view of a bolt means; Fig.7 is a side view of the bolt means of Fig.6 with its operating member; Fig.8 is a side view of a cover for the housing of the actuator means (shown inverted for simplicity); Fig.9 is a side view of a base for the housing of the actuator means; Fig.10 is a side view of a partially assembled actuator means, each bolt means being in the first position; Fig.ll is a side view of a partially assembled actuator means and associated keeper, each bolt means being in the locking condition in engagement with the keeper; Fig.12 is a plan view of a first embodiment of keeper for use with the actuating means;; Fig.13 is a plan view of a second embodiment of keeper; Fig.14 is a plan view of a third embodiment of keeper; Fig.15 is a side view of a locking mechanism according to the invention, with the cover removed, the bolt means being in the first position; and Fig.16 is a view as Fig.15, with the bolt means in the third position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The window assembly 1 of Figs. 1 and 2 includes a sash 2 hingedly mounted in fixed outer frame 6; sash 2 mounts glazing 4 in known manner.

The sash comprises a sash hinge part 2a, and a sash lock part 2b; parts 2a,2b are parallel and are interconnected by sash connecting parts 2c,2d. The outer frame correspondingly comprises an outer frame hinge part 6a, an outer frame lock part 6b and two outer frame connecting parts 6c,6d. The sash is pivoted upon hinges 8, used to secure the sash hinge part 2a to the outer frame hinge part 6a.

The sash lock part 2b carries the actuating means with two locking mechanisms 10. In this embodiment the actuating means is a cremone, and upon rotation of the handle 12 is thus adapted to drive two shoot bolts 14a,14b simultaneously in opposite directions into engagement with respective keepers 16a,16b; keepers 16a,16b are mounted respectively upon the outer frame connecting parts 6c,6d.

The actuating means 10 is located is the so-called "spare chamber" 20 of the hollow profile of sash lock part 2b, and is secured there by screws (not shown) passing though the lock part in known fashion. In the orientation as viewed, the lower wall of the spare chamber 20 has been locally removed to permit the insertion of the actuating means 10.

In alternative embodiments the actuating means is located in one of the so-called "drainage chamber", "reinforcing chamber", "Euro-groove" or other suitable chamber or recess in the hollow profile. In another alternative embodiment, in which the sash is solid, e.g. wood, the actuating means is secured to a surface thereof in known fashion.

Mounted to the outer frame lock part 6b adjacent the actuating means 10 is a keeper 22, which is engageable by a bolt carried by operating member 24a, as more fully described below. In the unlocking condition as shown in Fig.2, the bolt(s) do not project into the air gap 18 (between the sash lock part 2b and the frame lock part 6b) so that the size of the air gap 18 between these parts can be determined by the manufacturer or installer; usually the air gap will be made as small as is practical.

As more clearly seen in Figs.3 and 4, the actuating means with its two locking mechanisms 10 includes a housing 26 inside which are located the components of the mechanism as described below. Projecting from the housing are operating members 24a,24b, each of which may be connected to an (inward) end of a respective shoot bolt 12a,b, in known fashion. Operation of the actuator is effected by a shaft connecting the handle 12 to the square aperture 28.

Mounted in the housing 26 are a pair of bolts 30a,30b.

Bolts 30a,b in this embodiment are of T-section, each comprising a stem 32 and an enlarged head 34 (see also Fig.6). In an alternative embodiment the bolts are of Lsection. As described below, each bolt is carried by a respective operating member 24a,b, so that the bolts are also oppositely movable. The bolts 30a,b are adapted to engage a keeper 22 (Fig.5), the keeper 22 having axially extending undercut end portions 36a,36b of a shape and size to receive and locate the laterally enlarged head 34a,34b of a respective bolt.

Following entry of the bolt heads 34a,b into their respective keeper end portions 36a,b, movement of the panel relative to the frame will be resisted or prevented. Side walls 38a,38b of the keeper end portions will resist movement of the panel in the normal opening direction (i.e.

out of the paper as viewed in Fig.5); one or other of end walls 40a,40b will resist forcing movement of the panel and locking mechanism longitudinally relative to the keeper; and the enlarged heads 34a and 34b of the bolts cooperating with top walls 42a,42b of the undercut keeper end portions will resist forcing of the panel and locking mechanism away from the keeper (i.e. in a direction along the longitudinal axis of the bolts, generally in the plane of glazing 4).

As seen in Figs.6 and 7, bolt 30b has a stem 32b and a Thead 34b. One side of the stem 32b carries a series of raised angled guides 50b; the guides are at an angle A relative to the direction of movement of the operating member. The other side of the stem 32b has a lip 52b, which cooperates with a ledge 54b of the operating member 24b to limit the outward (downwards as viewed in Fig.7) movement of bolt 30b. The bolt 30b is mounted to slide within a channel-like recess 56b in the operating member 24b (in this figure, the recess is shown larger than the bolt for clarity, though in actual embodiments of the invention, the bolt will be a tight but sliding fit in the recess).

The angled guides 50b cooperate with correspondingly angled channels 60b in the housing cover 62 (Fig.8); thus, bolt 30b is mounted between the cover 62 and its operating member 24b. The other bolt 30a is mounted between its operating member 24a and the base 64 (Fig.9) of the housing; the operating member 24a has a recess in which the bolt 30a slides, the bolt having angled guides cooperating with correspondingly angled channels 66 in the base 64.

In the embodiment shown, there are approximately two and a half guide sections (and corresponding channel sections); in other embodiments there may be more of fewer guide and channel sections. The greater the number of guide and channel sections the greater the manufacturing cost, but the greater the engagement area between the guide and channel, so the greater the expected durability.

It will be seen from Fig.8 that the angled channels 60b terminate in enlarged recessed area 70b. Area 70b is bordered by sloping wall 72b and upstanding lip 74b. The depth of the recess 70b (and thus the height of the wall 72b and lip 74b) corresponds to the height by which the angled guides SOb upstand from the bolt stem 32b, so that the wall 72b and lip 74b act to retain the guided portion of the bolt 30b within the housing; specifically, the lip 74b (together with the lip 52b of the stem in cooperation with the ledge 54b of the operating member) retain the guides 50b within the housing, maintaining the bolt 30b in connection with the housing. In another, though less preferred embodiment, the lip 52b and ledge 54b are not present, so that the bolt is retained in the housing solely by the lip 74b cooperating with the guides 50b.

It will thus be understood that, in the assembled locking mechanism, the guides 50b are restrained to move only within the channels 60b and the adjoining recessed area 70b; it will be understood that movement of the guides within the channels 60b will be at the angle A, whilst movement in the area 70b will be substantially parallel to the longitudinal axis of the housing, and thus substantially parallel to the operating member first direction (i.e. the direction of movement of the operating member 24b).Since the bolt stem 32b is slidably retained in a recess 56b of the operating member 24b, it will be understood that movement of the operating member 24b relative to the cover 62 (i.e. relative to the housing 20) in its first direction, will cause angled movement of the bolt 30b whilst the guides 50b engage the channels 60b, and linear movement substantially parallel to the first direction whilst the guides are within recessed area 70b.

Thus, during a first part of the movement of the operating member 24b from the first or unlocking condition shown in Fig.3, the bolt tip, in this embodiment the bolt head 34b is caused to move outwardly and along the housing (at angle A) to its second (intermediate) position; during a second part of the movement of the operating member the bolt tip i.e. head, is caused move substantially parallel with the operating member to its third or locking position shown in Fig.4.

It will be understood that for some applications the provision of the recessed area 70b is not required, i.e.

the angled movement of the bolt means to its second position provides sufficient security for the chosen application. In such embodiment the second position will correspond to the locking condition. However, we prefer embodiments similar to those shown in the figures, wherein the bolt means is caused to move substantially parallel to the direction of movement of the operating member into the locking condition.

The side wall 76 of the cover 62 (and the corresponding side wall 78 of the base 64) have apertures 80a,80b to receive the respective T-heads of the bolts 30a,b. Thus, in the first or unlocking condition shown in Fig.3, the bolt heads are flush with the housing side wall, and only project therebeyond upon rotation of the handle 12 in aperture 28. Thus, a minimal air gap 18 between the panel and adjacent frame part can be utilised, the gap preferably being too small to accommodate an effective house-breaking tool.

Figs.10 and 11 show more detail of the cremone actuator of the actuating means 10. Thus, the handle (not shown in these figures) inserted into the square aperture 28 drives a first, part-circular cog 82. The cog 82 has teeth 84 which engage recesses in the first operating member 24a.

The operating member 24a extends beyond the first cog 82, and has a rack which engages pinion 86: pinion 86 engages a rack of the second operating member 24b, such that rotation of the handle causes movement of the operating members 24a,b In opposite directions, in shown fashion.

In the locking condition of Fig.ll, each bolt head 34a,b engages a respective undercut portion of the keeper 22.

In the embodiment of Figs.l-4 the bolt stems 32a and 32b are in the same plane; in order that the mechanism is not "handed", it is necessary that the bolt stems be in a central plane between the cover and the base. In another embodiment the bolt stems are offset from the central plane, each being offset by the same distance, but in opposite directions; this alternative embodiment also allows the mechanism to be non-handed, and may be preferred when one bolt is between the base and its operating member, and the other bolt is between its operating member and the cover.

Figs.12 shows a design of keeper 122 for use with offset bolts. Thus, the undercut end portion 136a is offset from the undercut end portion 136b.

In the embodiment of Fig.13, a further embodiment of keeper 222 is shown, having apertures 90a,90b for entry of the bolt heads 30a,30b into engagement with respective undercut end portions 236a,236b.

In Fig.14, a keeper 322 with a night vent facility is shown. In this keeper, a first pair of offset undercuts 336a,336b correspond to the fully closed panel position, i.e. with the window seals fully compressed, and a second pair of offset undercuts 337a,337b correspond to the panel in a slightly open condition, permitting ventilation as might for example be required at night.

In the embodiment of Figs.15 and 16, the locking mechanism 410 is in a separate housing 422 from the actuating means, and so may, for example, be used alongside a prior art actuating means. Within the housing 422 is retained the major part of an operating member 424 and a bolt 430. The bolt stem carries guides 450t the correspondingly angled channels 460 are located in the base 464. The base 464 includes a recessed area 470, so that movement of the operating member 424 (from the position shown in Fig.15 to that shown in Fig.l6) causes angled movement of the bolt 430 along and outwardly of the housing 422 followed by movement parallel to that of the operating member (as more fully described above).

Thus, in this embodiment the guides are located on the side of the bolt stem facing the base 464, and the channels are located in the base. In another embodiment the guides are located on the side of the bolt stem facing the cover and the channels are located in the cover. In yet another embodiment the bolt stem has guides to either side of the stem, and the housing has channels in both the base and cover. In alternative embodiments to those described above, the channels in the housing may be replaced by corresponding channels formed in the wall of the spare chamber, or formed in a separate plate secured thereto.

In the embodiments shown, the angle A is 450, and the movement of the operating member relative to the housing is 20mm; during the first l0mm of operating member movement the bolt is caused to project lOmm from the housing, and during the remaining lOmm of operating member movement the bolt moves parallel to the operating member. Thus, the bolt head can move up to lOmm under the undercut portion of the keeper, allowing a large area of contact therebetween, which is able to withstand considerable jemmying force.

It will be understood that other angles than 45 can be utilised for the guides and channels; thus, for an operating member movement of 20mm and a desired bolt projection of lOmm, an angle of 300 will provide a length of bolt movement parallel to the operating member of approximately 2.8mm, whereas an angle of 600 will provide a length of bolt movement parallel to the operating member of approximately 14.2mm. However, the greater the angle A, the greater will be the resistance to operating member movement provided by the locking mechanism.

Clearly, the amount of operating member movement provided by a given actuating means will be known, whilst both the desired bolt projection and the amount of bolt movement parallel to the operating member can be pre-determined, to arrive at the angle required for a given mechanism and arrangement.

It will be understood that a prior art actuating means (with sufficient operating member movement) may be connected to one end of the operating member 424, with the other end of the operating member 424 being connected to a shoot bolt. Alternatively, the ends of the operating member 424 can each be connected to respective parts of a shoot bolt so that the operating mechanism 410 is mounted in or upon the sash lock part at a desired location along the sash lock part i.e. between the actuating means and the shoot bolt tip. Additionally, a corner drive mechanism can be fitted at the junction of the sash lock part and one or both of the sash connecting parts, which corner drive mechanism drives a locking mechanism 410 mounted in or upon one or both of the sash connecting parts.

Claims

1. A locking mechanism which includes an operating member and bolt means mounted to move with the operating member in which the bolt means is mounted to slide relative to the operating member.

2. A locking mechanism which includes a movable operating member and bolt means mounted to be moved with the operating member into and out of a locking position, in which the bolt means is mounted also to slide relative to the operating member during movement of the operating member.

3. A locking mechanism according to claim 1 or claim 2 in which the operating member is movable in a first direction, and the bolt means is mounted to be moved by the operating member in said first direction, the mechanism having guide means for the bolt means adapted to move the bolt means at an angle to said first direction during movement of said operating member.

4. A locking mechanism according to claim 3 in which part of the bolt means is located in a housing, and part of the guide means is carried by or is integral with the housing.

5. A locking mechanism according to claim 4 in which the bolt means carries an angled guide member which cooperates with an angled channel member of the housing.

6. A locking mechanism according to claim 5 in which the angle of the guide member and channel member to the path of movement of the operating member is between 300 and 600.

7. A locking mechanism according to claim 5 in which the angle of the guide member and channel member to the path of movement of the operating member is 450.

8. A locking mechanism according to any of claims 5-7 in which there are a plurality of separate guide and channel members.

9. A locking mechanism according to any of claims 4-8 in which the operating member is partly enclosed within the housing and drivingly engages the bolt means, the bolt means having a free end, the free end having a first position and a second position, the free end projecting further from the housing in the said second position than in the said first position.

10. A locking mechanism according to claim 9 in which the free end of the bolt means is enlarged so as to cooperate with an undercut in a keeper.

11. A locking mechanism according to claim 9 or claim 10 in which the path of movement of the free end between the said first and second positions is linear.

12. A locking mechanism according to any of claims 9-11 in which the second position corresponds to a locking condition and the first position corresponds to an unlocking condition.

13. A locking mechanism according to any of claims 9-11 in which the bolt means has a third position which corresponds to the locking condition, the second position being intermediate between the first and third positions.

14. A locking mechanism according to claim 13 in which movement of the bolt means between its second and third positions is linear and substantially parallel to the said first direction of the operating member.

15. A locking mechanism according to any of claims 1-14 in which the bolt means is of T-section or of L-section.

16. A locking mechanism according to any of claims 1-15 in which the bolt means is slidable relative to the operating member in a second direction substantially perpendicular to the first direction of the operating member.

17. An actuating means with a locking mechanism, the actuating means having at least one operating member and bolt means cooperating with the said operating member, the bolt means having a free end, the bolt means having a first position and an second position, characterised in that the free end projects further from the actuating means in the second position than in the first position.

18. An actuating mechanism according to claim 17 having two oppositely-drivable operating members, each operating member cooperating with a bolt means, in which the respective bolt means are offset.

19. An actuating mechanism according to claim 18 in which the bolt means are offset by an equal distance, but in opposite directions, from the central plane of the mechanism.

20. A locking arrangement for a movable panel in a fixed frame in which the panel carries cremone actuating means and two shoot bolts, the cremone actuating means having two operating members, each operating member being connected to a respective shoot bolt, in which each operating member cooperates with a slidable bolt means, the bolt means having a bolt tip, each bolt means having a first position and a second position, the bolt tip being further from its operating member in the second position than in the first position, and in that the bolt means in its second position is engageable with a keeper mounted to the fixed frame.

21. A keeper for use with a locking mechanism according to any of claims 1-16, or with an actuating mechanism according to any of claims 17-19.

22. A locking mechanism constructed and arranged substantially as described with reference to Figs.15 and 16 of the accompanying drawings.

23. An actuating mechanism constructed and arranged substantially as described with reference to Figs.3-11 of the accompanying drawings.

24. A keeper constructed and arranged substantially as described with reference to Fig.5 or Figs.12-14 of the accompanying drawings.