GB2128240A - Numerical lock with secret code resetting device - Google Patents

Abstract

A numerical lock has two secret code resetting devices 10 each including a respective setting disc 12 which engages a tumbler disc 22 by a first indexing arrangement 20. The tumbler disc 22 engages a bottom plate 26 by a second indexing arrangement 24, and includes an insertion opening 38 for receiving a locking tongue 40 of an actuating slider member 42 which moves the latch projection 56 of a latch slider member 54 to allow a hasp member to be released from an opening 68. Code numerals are provided on a pitch circle of each setting disc 12, and that opposite the respective insertion opening 38 can be changed by rotation of the setting disc 12 while the respective locking tongue 40 is engaged in the insertion opening 38. The first indexing means 20 is stronger than the second means 24. <IMAGE>

Description

SPECIFICATION Numerical lock with secret code resetting device The invention relates to a numerical lock having a secret code resetting device, especially but not exclusively for bags and cases.

Many different forms of such locks are known, but they are relatively complicated in construction, and consequently are expensive and unreliable and are not suitable for simpler articles.

The present invention aims to provide a numerical lock that is more reliable and provides a high degree of security, while being of a relatively simpler design.

The invention is defined by claim 1 hereinafter.

A preferred embodiment of the invention is a numerical lock which has a simple design of secret code resetting device which co-operates with an equally simple actuating slider member. The actuating slider member is finally connected in a very simple manner to a latch slider member which is also simple in design. Although of simple design, the lock is convenient to operate and provides a relatively high level of security since the secret code can be altered on the secret code resetting device within wide limits. An entrainment member/slot coupling means between the latch slider member and the actuating slider member allows insertion of the closing eye of a hasp member even when the secret code has not been set. This feature provides maximum security as the secret code can be adjusted immediately after the lock has been opened, so that it cannot be ascertained by unauthorized parties.Nonetheless, the lock can be closed at any time.

Some examples of locks embodying the invention will now be described in detail with reference to the accompanying drawings, in which: Fig. 1 is a view from above of a first numerical lock embodying the invention, Fig. 2 is a partly broken-away view of the lock shown in Fig. 1, without the front plate, Fig. 3 is a view from below of the lock shown in Fig. 1, Fig. 4 is an end view of the lock of Fig. 1, showing setting discs, Fig. 5 is a side view of the lock shown in Fig. 1, Fig. 6 is a sectional view of the lock shown in Fig. 1 taken at a line VI--VI indicated in Fig. 2, Fig. 7 is a view from above, a view in longitudinal section and a view from below, of a tumbler disc, Fig. 8 is a view from above, a view in longitudinal section and a view from below of a setting disc, Fig. 9 is a perspective view of an actuating slider member of the lock of Fig. 1, Fig. 10 is a view from below of a further numerical lock having three successively disposed latch projections and embodying the invention, Fig. 11 is a partly cut-away view of the lock shown in Fig. 10, with the front plate removed, and Fig. 1 2 is a view from below of the lock shown in Fig. 10.

Figs.1,4 and 5 show various general views of a numerical lock. The lock has a front plate 2 which encloses the lock assembly at the front and at the side portions and secures the lock assembly. The lock has an actuating knob 4 with which the closing eye 6 of a hasp member 8 can be released.

The lock is provided with two secret code resetting devices 10, only the setting discs 12 of each thereof projecting out of the front plate 2.

The actual lock portion 14 of the numerical lock is connected for example to the wall 16 of a container such as a bag. For that purpose, fixing lugs or tabs 18 are fitted through the wall 1 6 of the container and bent over on the rear thereof.

The hasp member 8 is for example secured to the cover or lid of the container.

Each resetting device 10 of the lock has a first detent means 20 (Fig. 6) which is arranged between a setting disc 12 and a tumbler disc 22.

A second detent means 24 is disposed between the tumbler disc 22 and a bottom plate 26 of the lock assembly. The detent means 20 and 24 each have projections 28 which are disposed on both sides of the tumbler disc 22 and which co-operate with openings or recesses 30 in the bottom plate 26 and in the setting disc 1 2 respectively. The setting disc 1 2 and the tumbler disc 22 are biased against the bottom plate 26 by means of a plate spring 32 which bears against a cover plate 34 of the lock assembly. The bottom plate 26 and the cover plate 34 are secured to a frame member 36 of the lock assembly.

The first detent means 20, which allows resetting of the secret code by rotary movement of the setting disc 12 relative to the tumbler disc 22, has a greater retaining force than the second detent means 24. The second detent means 24 serves for fixing the position of the secret code resetting devices. In order to provide the different retaining forces, the tumbler disc 22 is provided on its underside with a smaller number of projections 28, than on its top side, as shown in Fig. 7.

Each tumbler disc 22 has an insertion opening 38 for receiving a locking tongue portion 40 of an actuating slider member 42. The actuating slider member 42 which also carries the actuating knob 4, is slidable in the lock assembly frame 36 along the centre line between the resetting devices 10, parallel to two sides of the frame 36, as can be seen from Figs. 2 and 3. The actuating slider member 42 has two locking tongue portions 40, best shown in Fig. 9, each of which co-operates with a secret code resetting device 10. The actuating slider member 42 includes a projection 44 which projects between the secret code resetting devices 10 and in which there is means, preferably a bore 46, for accommodating the spring 48 (Fig. 2) which is in the form of a coil spring.The spring 48 bears against a side portion 50 of the lock assembly and serves to bias the actuating slider member 42 away from the discs 22.

The actuating slider member 42 co-operates by way of an entrainment member/slot coupling means 52 with a latch slider member 54 which has at least one latch projection 56. For that purpose, the actuating slider member 42 has entrainment members 58 which engage with the latch slider member 54 by entering slots 60 in the latch slider member 54, in such a way that the eye 6 of the hasp member 8 can be inserted into the engaged position-even when the actuating slider member 42 is blocked by the tumbler discs 22. A recess 62 in the actuating slider member 42 serves to accommodate a spring 64 which locates on and bears against a projection 66 on the latch slider member 54 and serves to bias the latch slider member 54 in the closing direction.

The cover plate 34 of the lock assembly includes an entry opening 68 (Figs. 2 and 6) for the eye 6 of the hasp member 8. On the side of the entry opening 68 which is opposite to the latch projection 56, the cover plate 34 is provided with two tongue-like ejector springs 70 which cause the eye 6 and therefore the hasp member 8 to be ejected when the latch projection 56 has been retracted, by means of the actuating knob 4 and the actuating slider member 42. The relative arrangement of the springs 70 and the latch projection 56 can be seen from Fig. 3.

To actuate the lock, it is necessary for the secret code resetting devices 10 to be set to the secret code. The openings 38 in the tumbler discs 22 are then disposed parallel to each other and are opposite to the locking tongue portions 40 on the actuating slider member 42. The actuating slider member 42 can then be actuated by means of the actuating knob 4, with the locking tongue portions 40 moving into the openings 38. When that happens, the latch slider member 54 is entrained by way of the entrainment member/slot coupling means 52, i.e. the entrainment members 58 draw the latch slider member 54 away from the eye of the hasp member 8. That results in retraction of the latch projection 56 so that the eye 6 of the hasp member 8 is released and the eye 6 is ejected by means of the ejector springs 70.

To reset the secret code, the old secret code first has to be set, and the actuating slider member 42 has to be moved into the open position by means of the actuating knob 4. The locking tongue portions 40 then block any further rotary movement of the tumbler disc 22. The first detent means 20 is overcome, by rotation of the setting discs 12, and a fresh secret code can be set.

Figs. 10 to 12 show another embodiment of the lock which substantially corresponds to the lock described above, but in which the latch slider member 72 has three successively disposed latch projections 74 which engage into suitable recesses 76 on the one hand arranged within the frame 36 and on the other hand in an additional frame 78 which adjoins the frame 36. The frame 36 and the additional frame 78 are held together by a common front plate 80.

Claims (8)

1. A numerical lock with a secret code resetting device, characterised by: at least two secret code resetting devices each having a tumbler disc which co-operates by way of a first detent means with a setting disc and which is provided with an insertion opening for a locking tongue portion and which bears against a housing member by way of a second detent means, wherein the retaining force of the first detent means is greater than that of the second detent means and wherein the setting disc and the tumbler disc lie parallel to the said housing member which is substantially flat:: an actuating slider member which is displaceable along the centre line between the said two secret code resetting devices parallel to the said housing member, has two locking tongue portions which are disposed parallel to the direction of displacement towards the tumbler discs, is biased away from the tumbler discs by means of a spring, and is provided with an actuating knob; and a latch slider member which has at least one latch projection and is biased in the closing direction by means of a spring and is coupled with the actuating slider member in such a way that with the actuating slider member in the locking position the latch slider member permits insertion of a closing eye of a hasp member.

2. A lock according to claim 1 , wherein the detent means have projections which are arranged along pitch circles and which co-operate with recesses in adjoining members, and each setting disc is biased against the tumbler disc by a spring which bears against a cover plate, and said tumbler disc is biased against a bottom plate.

3. A lock according to claim 1 or 2, wherein the actuating slider member has a projection which projects between the secret code resetting devices, said projection having means for accommodating a coil spring arranged to bias the actuating slider member.

4. A lock according to claim 1 or 2, wherein the actuating slider member has along its centre line, a recess for accommodating a coil spring biasing the latch slider member, the spring bearing against a projection on the latch slider member.

5. A lock according to claim 1, wherein at least one tongue-like ejection spring is provided at the side of an opening for the closing eye.

6. A lock according to claim 1, wherein the latch slider member has a plurality of latch projections which are disposed in succession and at a spacing from each other and each latch projection engages into a separate recess.

7. A numerical lock substantially as described hereinbefore with reference to Figs. 1 to 9 of the accompanying drawings.

8. A numerical lock substantially as described hereinbefore with reference to Figs. 10, 11 and 1 2 of the accompanying drawings.