GB2270343A

GB2270343A - Multi point door lock

Info

Publication number: GB2270343A
Application number: GB9317797A
Authority: GB
Inventors: Eric Hassell
Original assignee: Parkes Josiah & Sons Ltd
Current assignee: Parkes Josiah & Sons Ltd
Priority date: 1992-09-05
Filing date: 1993-08-26
Publication date: 1994-03-09
Anticipated expiration: 2013-08-26
Also published as: GB2270343B; GB9317797D0

Abstract

A multi-point door lock has a central lock unit 1 and remote lock units 2 and 3 each bearing dead bolts 4 - 6 which can be extended and retracted together by handles 11. The handles normally turn a gear plate 57 in the unit 1 which operates the central bolt 4 through a second plate 49 and operates the remote bolts 5 and 6 through a drive bar 12 linked to the plate 49. When the bolts are extended the handles can be disconnected from the plate 57 to prevent force being applied to retract the bolts. This is achieved by operating an internal thumb turn 13 or external locking cylinder (not shown) to pivot a lever 71 in the unit 1 which normally guides a drive peg 68 to engage the gear plate 57. <IMAGE>

Description

Locks The present invention relates to locks for doors or other such closures and more particularly relates to so-called multi-point locks of the kind comprising a main lock unit including a dead bolt which can be extended and retracted from each side of the closure by the manipulation in appropriate senses of respective handles associated with the main lock unit, and at least one further lock unit located remotely from the main lock unit and including a further dead bolt which can be extended and retracted in unison with the first-mentioned dead bolt by means of a drive linkage extending from the main lock unit to the further lock unit. Such a lock will hereinafter be referred to as a multi-point lock of the kind specified.

Typically there are two such further lock units both linked to the main unit, the main unit being mounted centrally along the opening edge of the closure while the further units are mounted towards the upper and lower edges thereof.

In a known arrangement of a multi-point lock of the kind specified, the mechanism can be locked and unlocked with the dead bolts in their extended positions by means of a key operated locking cylinder or by manipulation of a thumb turn on the inside of the closure, and by means of a key-operated locking cylinder on the outside, in either case the locking operation being effective to place an abutment in the path of an element of the mechanical transmission within the main lock unit which converts movement of the handles to retraction of the bolts, whereby to block the handles against movement in the sense to retract the bolts.A disadvantage of this arrangement, however, is that it may be possible for the blocking effect of the abutment to be overcome and the dead bolts consequently retracted in an attack from the outside of the closure by the application of gross force to the transmission through the handle on that side.

The present invention seeks to alleviate this problem and accordingly resides in a multi-point lock of the kind specified comprising means within the main lock unit which are operable, when the dead bolts are extended, to disconnect the transmission of movement to the bolts from at least that handle which is on the outside of the closure to which the lock is in use mounted, in the sense to retract the bolts. In this way it becomes impossible to gain unauthorised entry through the closure by the application of any level of force to the outside handle as this will not be transmitted from the handle to the bolts.

Further features of the invention will become apparent from the following more particular description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings in which: Figure 1 is a perspective view of a multi-point lock in accordance with the invention as mounted for use on a door; Figures 2 to 7 are side elevations of the inside of the main lock unit in the course of the assembly of its internal mechanism; and Figure 8 is an enlarged side view of the decoupling lever incorporated in the main lock unit.

Referring to Figure 1, the illustrated multi-point lock comprises a central, main lock unit 1 and upper and lower end units 2 and 3 all mounted rim-wise to the inside face of a hinged door D along its opening edge. The three lock units 1, 2 and 3 comprise respective dead bolts 4, 5 and 6 each expendable and retractable in relation to its respective casing 7, 8 or 9. The main lock unit 1 also includes a spring bolt 10, which in the illustrated embodiment is of the so-called easy action kind. A lever handle 11 is journalled in the main lock unit 1 and is normally spring-biased to the illustrated horizontal rest position, from which it can be displaced through approximately 450 both clockwise and anti-clockwise. A similar handle (not shown) is linked to the unit 1 from the outside of the door.Appropriate staples (not shown) to receive the bolts 4-6 and 10 will be mounted to the facing door jamb.

When the dead bolts 4-6 are retracted, the illustrated lock acts as a simple latch in which only the spring bolt 10 is effective, permitting slam-closing of the door, retraction of the spring bolt to open the door in this mode being effected by depression of either of the handles. For greater security, however, the dead bolts 4-6 will also be extended when the door is closed, which is achieved by lifting either handle from the rest position. A lost-motion coupling within the main lock unit then allows the handles to return to the rest position while the bolts remain extended. When the dead bolts 4-6 have been extended they can be locked and the handles 11 effectively uncoupled from them to prevent their retraction from either side of the door, by the manipulation of a thumb turn 13 on the main lock unit (i.e. from the inside of the door).An equivalent action can be effected from the outside of the door by means of a key-operated locking cylinder (not shown).

In an alternative arrangement, the thumb turn 13 on the inside is itself replaced by another key-operated cylinder. Subsequent retraction of all four bolts to open the door is by depression of either handle from the rest position (following unlocking of the bolts and reconnection of the handles by means of the appropriate locking cylinder or thumb turn). The aforesaid lostmotion coupling then allows the handles to return to the rest position while the three dead bolts remain retracted until the handles are lifted again.

The end unit bolts 5 and 6 are moved in unison with the main unit dead bolt 4 through the agency of a reciprocable drive bar 12 which links all three units.

Lifting of this bar through the main unit mechanism causes the end unit bolts to be extended while lowering of the bar causes them to retract, the end units 2 and 3 incorporating known mechanism for converting the motion of the bar 12 into perpendicular movement of the bolts 5 and 6.

The mechanism within the main lock unit 1 for effecting the movement of the bolts and for uncoupling the handles will now be more particularly described. The disposition of the components within the main unit is conveniently illustrated by considering the sequence of their assembly within the casing 7. For this purpose reference is made to Figures 2-7 which illustrate the interior of the casing during successive stages of assembly; (the lock illustrated in those Figures is in fact of opposite hand to that shown in Figure 1).

With reference to Figure 2 there is shown the interior of the casing 7 fitted with a bush 14 for the thumb turn 13 and a bush 15 for the handle 11. The forend of the casing is apertured at 16 and 17 to pass the heads of the bolts 10 and 4 and its top and bottom edges are recessed at 18 and 19 to pass the drive bar 12. Various posts 20-29 extend from the side wall of the casing to act as pivots, stops, guides and/or fixings for other components as will become apparent from the ensuing description. A plastics deflector block 30 is mounted behind the forend and over the post 25 for a purpose which will also be described in due course.

Figure 3 shows the addition of the bolts 10 and 4, a turn plate 31 and spring bolt follower 32. The spring bolt has a head 33 guided through the casing aperture 16 and a tail 34 guided on the post 24. The dead bolt 4 has a head 35 guided through the casing aperture 17 and a tail 36 guided on the post 28. The turn plate 31 is fastened upon a non-circular spigot 37 extending from the rear of the thumb turn 13 so as to turn therewith, the limits of this movement being set at 900 anti-clockwise from the illustrated position (in the sense as viewed) by the abutment of ears 38A,38B against the post 22. The turn plate itself carries three pegs 39-41 for purposes to be described.The spring bolt follower 32 is borne around the bush 15 and has a drive lug 42 one end face of which engages a peg 43 on the spring bolt tail so that clockwise (as viewed) movement of the follower is effective to retract that bolt, the other end face of the lug 42 engaging the post 27 to set the limit of its return movement. The lug 42 also carries a peg 44 for a purpose to be described.

Figure 4 shows the addition of a detent spring 45, a blocking lever and spring 46,47, a spring plate 48 and a drive plate 49. The lever 46 is pivoted on post 23 and urged up by its spring 47 against the peg 40 on the turn plate 31 for a purpose to be described. The action of the spring 45 on the peg 39 of the turn plate provides a detent for the thumb turn at its two operative positions 900 apart. The spring plate 48 is borne around the bush 15 coaxially with but separate from the follower 32 and has a lug 50 which sets the limit of its clockwise (as viewed) movement by engagement with the post 26. The lug 50 also carries a peg 51 for a purpose to be described.The plate 49 is borne upon the post 28 and has a drive lug 52 engaging between a pair of pegs 53 on the dead bolt tail 36 so that rotation of the plate 49 in the clockwise sense as viewed (by means yet to be described) is effective to extend the dead bolt 4 and return rotation of that plate is effective to retract that bolt. The plate 49 also carries a drive peg 54 which in the completed lock assembly will engage in a slot in the drive bar 12 to raise and lower the same, and thereby extend and retract the end unit bolts 5 and 6, in unison with the extension and retraction of the main unit dead bolt 4.

Figure 5 shows the addition of the spring 55 for bolt 10, a spacer 56 on the peg 39 of turn plate 31, a gear plate 57, and a plastics detent member 58 for the drive plate 49. The gear plate 57 is borne around the bush 15 coaxially with the follower 32 and spring plate 48. Its limit of clockwise (as viewed) movement is set by engagement with the peg 51 on the spring plate lug 50, and so that any anti-clockwise (as viewed) movement of the spring plate from the illustrated position will correspondingly turn the gear plate. This gear plate is formed with a series of gear teeth 59 in mesh with similar teeth 60 on the drive plate 49 so that any rotation of the gear plate is accompanied by rotation of the drive plate in the contrary sense.

Figure 6 shows the addition of the inside handle 11, a handle follower 61 and a drive link 62. The handle has a spigot 63 by which it is journalled in the bush 15 and secured by a circlip 64. The spigot 63 has a pair of flats over which the follower 61 is located so as to turn always with the handle 11. This spigot also has a square-sectioned socket 65 which in the installed assembly will receive a spindle linking the two handles to turn together. The handle follower 61 has a pair of ears 66,67 which abut respectively the peg 44 on spring bolt follower 32 and the peg 51 on spring plate 48, with the effect that depressing either of the handles turns the spring bolt follower 32 clockwise (as viewed) while raising either of the handles turns the spring plate 48 in the contrary sense.The drive link 62 is pivoted at one end upon the peg 44 of the spring bolt follower 32 and carries at its other end a peg 68 for a purpose to be described.

Figure 7 shows the addition of the handle spring 69 and a guide bush 70 therefor, a decoupling lever 71, a link plate 72, a plastics spacer 73 and some trim inserts 74 for the drive bar recesses in the casing 7. The spring 69 acts between the pegs 44 and 51 to keep them in contact with the respective handle follower ears 66 and 67 when the handles are respectively depressed or raised, and such as always to urge the handles back to the illustrated horizontal rest position after any manipulation thereof. The decoupling lever 71 is a plastics moulding of the form also shown to an enlarged scale in Figure 8. It is pivoted on the post 23 with an upper limb 75 held against the peg 41 of the turn plate 31 in the illustrated condition, and a lower limb 76 directed down towards the handle axis. A guide slot 77 is formed in the rear of the limb 76 for a purpose to be described.The link plate 72 is pivoted on the post 23 and engages over the peg 39 of the turn plate 31, behind the spacer 56. In the installed assembly it receives a drive bar from the outside locking cylinder so that by turning the proper key in the cylinder the plate 72 can be pivoted in corresponding senses to turn the plate 31 between its two operative positions. The spacer 73 is mounted over the post 28 and around the bush 70 and is formed at its lower end with two recesses 78 which engage with the resilient member 58 on the drive plate 49 to provide a detent action for that plate in its two rotary positions corresponding to full retraction and full extension of the dead bolts.

The assembly is completed by adding the drive bar 12 (not shown in Figure 7) and the casing 7 is closed by a cap (also not shown) secured by screws into the threaded posts 21, 23, 25, 28 and 29.

The operation of the mechanism within the main lock unit 1 will now be explained, principally by reference to Figure 7 which shows the mechanism in the unlocked condition with the dead bolts retracted. In this condition the unit acts as a simple latch, with only the spring bolt 10 being effective. In this condition (as in all others) the spring bolt 10 is withdrawn by depressing either handle, which causes the handle follower ear 66 to drive the peg 44 of the bolt follower 32 clockwise (as viewed) so that the lug 42 drives the bolt peg 43 rearwards. Springs 55 and 69 return the bolt 10, follower 32 and handles to their illustrated rest positions after any such retraction.

To extend the dead bolts from this condition the handles are raised. This causes the handle follower ear 67 to drive the gear plate 57 anticlockwise (as viewed) via the peg 51 of the spring plate 48, thereby turning the drive plate 49 to extend dead bolt 4 and to raise the drive bar 12 via peg 54 to extend also the end unit dead bolts 5 and 6. Release of the handles then allows them and spring plate 48 to return to the rest position under the action of spring 69 on peg 51. Gear plate 57 and the rest of the dead bolt transmission remain in the extended position however, with plate 57 now lying up against post 43 (Fig 6). To retract the dead bolts from this condition the handles are depressed, which causes the peg 44 on the bolt follower 32 to move clockwise (as viewed) as described above. This peg carries one end of the drive link 62.

In this condition the peg 68 at the other end of the drive link is positioned at the entrance of the arcuate slot 77 in the decoupling lever 71, and that lever is held in its illustrated position by the engagement of the peg 41 with its upper limb 75. Turning the peg 44 therefore causes the peg 68 to run along the slot 77 and in so doing drives the gear plate 57 back clockwise (as viewed) to retract the dead bolts. Release of the handles then allows the follower 32 and drive link 62 to return to the rest position under the action of spring 69 while the gear plate 57 and the remainder of the dead bolt transmission remain in the retracted position.

To secure the mechanism after extending the dead bolts, however, the turn plate 31 is moved through 900, by manipulation of the thumb turn 13 on the inside of the door or by means of the outside key-operated cylinder.

This has two actions. Firstly, the blocking lever 46 is pivoted down by the peg 40 so as to lie behind the gear plate 57 (which has moved anti-clockwise to extend the bolts) and thereby block the dead bolt transmission against retraction under end pressure on the bolts; (note e.g. from Figure 6 that the turn plate 31 cannot be moved until the dead bolts have been extended and the top end of gear plate 57 has cleared the lower surface of lever 46). Secondly, the decoupling lever 71 is lifted around its pivot 23 by the peg 40 hooking under its upper limb 75. The lower limb 76 of that lever is therefore lifted away from the handle axis. This in turn pivots the drive link 62 out about the peg 44 into contact with the block 30, with its peg 68 lying under the nose 79 of the lever 71.If the handles are now depressed, the peg 68 cannot follow its previous locus through the slot 77 but instead is lifted without contact with the gear plate 57 and in so doing turns the decoupling lever 71 further clockwise (as viewed) about its pivot 23. In other words, the handles are now disconnected from the dead bolts in the sense that no force applied to the handles can be transmitted to the dead bolts to retract the same in this condition. To re-establish the connection and retract the bolts when required the turn plate 31 is turned back to its original position, so that its peg 41 pivots the decoupling lever 71 down once more and the drive link peg 68 is consequently repositioned in the slot 77 so as to be directed into engagement with the gear plate 57 when the handles are depressed. The lever 46 also returns to its unblocking position under the action of its spring 47 as it is released by the peg 40.

Claims

1. A multi-point lock for a door or other such closure comprising: a main lock unit including a dead bolt which can be extended and retracted from each side of the closure by the manipulation in appropriate senses of respective handles associated with the main lock unit; at least one further lock unit located remotely from the main lock unit and including a further dead bolt which can be extended and retracted in unison with the first mentioned dead bolt by means of a drive linkage extending from the main lock unit to the further lock unit; and isolating means within the main lock unit which are operable, when the dead bolts are extended, to disconnect the transmission of movement to said bolts from at least that handle which is on the outside of the closure to which the lock is in use mounted, in the sense to retract said bolts.

2. A lock according to claim 1 further comprising blocking means within the main lock unit which are operable in unison with said isolating means to block forced retraction of said bolts.

3. A lock according to claim 1 or claim 2 wherein the mechanism within the main lock unit is arranged such that operation of said isolating means to disconnect the transmission as aforesaid is blocked unless said bolts are extended.

4. A lock according to any preceding claim wherein operation of said isolating means is effected in response to the turning of a rotatable control member within the main lock unit.

5. A lock according to claim 4 comprising a key recognition mechanism accessible on the outside of the closure for turning said control member.

6. A lock according to claim 4 or claim 5 comprising a key-recognition mechanism accessible on the inside of the closure for turning said control member.

7. A lock according to claim 4 or claim 5 comprising a manually operable member accessible on the inside of the closure for turning said control member.

8. A lock according to any preceding claim wherein extension and retraction of said bolts is effected in response to the turning of a rotatable drive member within the main lock unit.

9. A lock according to claim 8 wherein said drive member is operable through lost-motion means by said handles such that turning either handle in one sense from a rest position and returning the handle to said rest position is effective to extend the bolts while turning either handle in the opposite sense from said rest position and returning the handle to said rest position is effective to retract the bolts.

10. A lock according to claim 8 or claim 9 wherein said isolating means are operable to disconnect the transmission of movement to said drive member from at least that handle which is on the outside of the closure, in the sense to retract said bolts.

11. A lock according to claim 10 wherein said handle is associated with a drive element within the main lock unit such that, while said bolts are extended and said isolating means are not operated, manipulation of said handle in an appropriate sense causes the drive element to follow a first path in which it engages the drive member to retract the bolts but, while the bolts are extended and the isolating means are operated, such manipulation of the handle causes the drive element to follow a second path in which it does not engage the drive member.

12. A lock according to claim 11 wherein said drive element comprises an abutment said first path for which is defined by a track formed in a member borne within the main lock unit when said member is in a first position but which member is moved out of said position when the isolating means are operated.

13. A lock according to claim 2 and claim 8 or any other claim appended to claim 8 wherein said blocking means comprise an abutment within the main lock unit which is arranged to be moved into the path of said drive member.

14. A lock according to any preceding claim wherein said main lock unit includes also a spring bolt which is retractable by either said handle independently of the condition of said isolating means.

15. A multi-point lock substantially as hereinbefore described with reference to the accompanying drawings.