Lock and bolt for a lock

Abstract

 The invention relates to a lock, comprising a lock part for mounting against or in a door, in which a bolt provided with a bevelled side is slidably mounted, and a staple part or closing plate for mounting against a door jamb provided with an opening into which the bolt drops when a door is closed. In order to prevent the lock being opened using a flexible 'shim' by pressing this shim between the door and the door jamb, a bevelled side of the bolt is shortened such that this bevelled side drops wholly inside the staple part or the closing plate in the closed position. In order to make this method of opening the door completely impossible the bolt is moreover provided with a groove which runs perpendicularly of a direction of movement of the bolt and in which an edge of the flexible shim comes to lie.

Description

[0001] The invention relates to a lock, comprising a lock part for mounting in or on a door, in which a bolt provided with a bevelled side is slidably mounted, and a staple part or a closing plate for mounting against a door jamb provided with an opening into which the bolt drops when the door is closed.

[0002] Locks of this type are generally known. They are for instance applied in substantially any front door in order to achieve that the front door locks automatically when it is pulled shut. The bevelled side here comes into contact with an edge of the staple part or the closing plate, and the bolt is pressed inward counter to the action of a spring up to the moment at which the bolt can drop into the opening. The drawback of the known lock is that a plate-like object can be pushed between the door jamb and the door such that an edge of this plate-like object comes to rest against the bevelled side of the bolt. If the plate-like object is now pushed further inward the bolt then slides into the lock part counter to the action of the spring, and the door can be opened.

[0003] The lock according to the invention obviates this drawback in that the bevelled side of the bolt takes a relatively obtuse form such that the bevelled side is positioned at least substantially wholly inside the staple part or the closing plate when the door is closed. In this way it is easily possible to prevent the bolt being pressed into the lock part by a plate-like object during 'shimmying' because the force exerted by the plate-like object is perpendicular of a possible direction of movement of the bolt.

[0004] In the lock according to the invention the short side is provided with a groove running at least substantially perpendicularly of a direction of movement of the bolt over a full width of the bolt. A plate-like object which is pressed against the side of the bolt during shimmying will then come to lie in the groove, whereby it is practically impossible to exert a laterally directed force on the bolt.

[0005] A lock according to the preamble of claim 1 is known in the field. During mounting of the lock according to the invention it is important to mount the staple part or the closing plate such that an edge of the staple part or the closing plate only just comes into contact with the bevelled side and that the bevelled side can still disappear almost completely into the staple part. The lock according to the invention achieves this owing to the characterizing measure that a transition from a short side of the bolt to the bevelled side is provided with a first rounding which in a situation of use comes into contact with the edge of the staple part or the closing plate, whereby mounting can be significantly simplified.

[0006] According to a further characterizing measure the groove moreover has in a transverse direction a concave, at least substantially half-round profile so that the edge comes to lie at the bottom, practically in the centre of the groove, whereby it is impossible to exert a laterally directed force on the bolt using the plate-like object. The concave profile results in a relatively shallow groove being sufficient, whereby notch effect is prevented and the bolt retains its strength.

[0007] According to a further characterizing measure, an edge of the groove positioned close to the bevelled side is provided with a second rounding which is a continuation of the first rounding, so that the first rounding and the second rounding together form a non-sharp rib via which an edge of the plate-like object is guided to the groove.
The non-sharp rib ensures a good closure.

[0008] According to a first preferred embodiment of the lock according to the invention, the groove has a substantially semicircular shape in a transverse direction. According to a further development of the first embodiment, the rib has a substantially semicircular shape. According to yet another development of the first embodiment, the bevelled side has a substantially partially circular shape. A semicircular and partially circular shape is understood to mean respectively a shape of a semicircle and a part of a circle which can be defined by means of a radius. The circular shapes follow a smooth progression and make possible a compact bolt which is burglar-proof and also closes properly.

[0009] A width of the groove preferably corresponds at least substantially to a distance between the lock part and the staple part or the closing plate, so that an edge of the plate-like object inevitably comes to lie at the bottom of the groove.

[0010] The invention also relates to a bolt as described as part of a lock according to the invention.

[0011] The invention will now be further elucidated with reference to the following figures, in which:

Fig. 1

is a cross-sectional view of a prior art lock provided with a staple-like part;

Fig. 2

is a cross-sectional view of a possible embodiment of a lock according to the invention provided with a staple-like part;

Fig. 3

is a cross-sectional view of a prior art lock provided with a closing plate;

Fig. 4

is a cross-sectional view of a possible embodiment of a lock according to the invention provided with a closing plate;

Fig. 5A

is a cross-sectional view of a prior art lock together with a closing plate;

Fig. 5B

is a cross-sectional view of a lock according to the invention.

[0012] Fig. 1 is a cross-sectional view of a prior art lock, consisting of a lock part 1 which can be mounted on a door 2 and a staple-like part 3 which can be mounted on a door jamb 4. Lock part 1 comprises a bolt 5 which drops into an opening 6 of staple-like part 3 when the door is pulled shut, after which the door is closed and locked. In order to open the door again from the inside a handle 7 is provided with which bolt 5 can be pulled out of opening 6 via a pull rod 8 counter to the action of a spring 9. The free stroke of bolt 5 is limited here by a rib 10 which is pressed into a cover 11 of lock part 1. Generally provided for the purpose of opening the door from the outside is a cylinder lock (not shown) via which bolt 5 can also be pulled out of opening 6. In order to allow bolt 5 to drop smoothly into opening 6 during closing of door 2, bolt 5 is provided with a bevelled side 12 which makes contact with staple-like part 3 during closing and which is pressed into lock part 1 by staple-like part 3 counter to the action of spring 9. It is this bevelled side 12 which also makes it possible for the lock to be opened relatively easily from the outside by a burglar. It is sufficient here to slide in a flexible plate-like object 13, for instance a credit card, via a gap between door 2 and door jamb 4 until plate-like object 13 rests against bevelled side 12 of bolt 5. By now pressing forcefully on plate-like object 13 the bolt 5 is pressed into lock part 1 counter to the action of spring 9, and the door can be opened.

[0013] Fig. 2 is a cross-sectional view of a possible embodiment of a lock according to the invention, likewise consisting of a lock part 1 which can be mounted on a door 2 and a staple part 3 which can be mounted on a door jamb 4. Lock 1 comprises a bolt 5 according to the invention, of which a relatively short bevelled side 12 drops into opening 6 of staple-like part 3 when the door is pulled shut, after which the door is closed and locked. In order to open the door again from the inside a handle 7 is provided with which bolt 5 can be pulled out of opening 6 via a pull rod 8 and counter to the action of a spring 9. The free stroke of bolt 5 is limited here by a rib 10 which is pressed into a cover 11 of lock part 1. Generally provided for the purpose of opening the door from the outside is a cylinder lock (not shown) via which bolt 5 can also be pulled out of opening 6. In order to allow bolt 5 to drop smoothly into opening 6 during closing of door 2, bolt 5 is provided with a first rounding 14 which makes contact with staple part 3 during closing and which is pressed into lock part 1 by staple part 3 counter to the action of spring 9. Because bevelled side 12 drops wholly inside staple-like part 3 in a closed position, it is practically impossible to open the lock by sliding in a plate-like object 13 via a gap between door 2 and door jamb 4. In order to make this method of opening the lock completely impossible bolt 5 is moreover provided with a groove 15 having a width at least corresponding to the width of the gap between door 2 and door jamb 4. Plate-like object 13 then comes to lie at the bottom of groove 15, whereby it has become impossible to exert a force in the direction of movement of bolt 5. In the case of an existing lock it is generally sufficient to replace the existing bolt with a bolt according to the invention, while the other components of the lock, such as pull rod 8, spring 9 and rib 10, can remain unchanged. The transition from first rounding 14 to groove 15 is further preferably provided with a second rounding 16, wherein first rounding 14 and second rounding 16 together form a non-sharp rib.

[0014] During closing of door 2 bolt 5 is pressed into lock part 1 using the relatively short, steep bevelled side 12. The intuitive expectation would be that this now requires more force and so will be more difficult. The opposite is found to be the case. Less force is necessary, and the forces occurring in lock part 1 are also smaller, whereby less wear occurs and the lifespan of the lock can be extended.

[0015] Fig. 3 is a cross-sectional view of a further prior art lock, consisting of a lock part 1 which can be mounted in a door 2 using a mounting plate 17 and which can co-act with a closing plate 18 mounted on door jamb 4. Lock part 1 comprises a bolt 5 which drops into an opening 6 of mounting plate 17 when the door is pulled shut, after which the door is closed and locked. Provided for the purpose of opening the door again is for instance a doorhandle 19 or a cylinder lock (not further shown) with which bolt 5 can be pulled out of an opening 21 in closing plate 18 via a pull rod 8 and a mechanism 20. In order to allow bolt 5 to drop smoothly into opening 21 during closing of door 2, bolt 5 is provided with a bevelled side 12 which makes contact with a slightly curved edge of closing plate 18 during closing, whereby bolt 5 is pressed into lock part 1. It is this bevelled side 12 which also makes it possible for the lock to be opened relatively easily from the outside by a burglar. It is sufficient here to slide in a flexible plate-like object 13, for instance a credit card, via a gap between door 2 and door jamb 4 until plate-like object 13 rests against bevelled side 12 of bolt 5. By now pressing forcefully on plate-like object 13 the bolt 5 is pressed into lock 1 and the door can be opened.

[0016] Fig. 4 is a cross-sectional view of a possible embodiment of a lock according to the invention, likewise consisting of a lock part 1 which can be mounted in a door 2 and a closing plate 18 which can be mounted on a door jamb 4. Lock 1 comprises a bolt 5 according to the invention, of which a relatively short bevelled side 12 drops into opening 21 of closing plate 18 when the door is pulled shut, after which the door is closed and locked. Provided for the purpose of opening the door again is for instance a doorhandle 19 or a cylinder lock (not further shown) with which bolt 5 can be pulled out of an opening 21 in closing plate 18 via a pull rod 8 and a mechanism 20. In order to allow bolt 5 to drop smoothly into opening 21 during closing of door 2, bolt 5 is provided with a bevelled side 12 which makes contact with closing plate 18 during closing, whereby bolt 5 is pressed into lock part 1. In a closed position this bevelled side 12 lies wholly inside opening 21 in closing plate 18. It is hereby practically impossible to open the lock by sliding in a plate-like object 13 via a gap between door 2 and door jamb 4. In order to make this method of opening the lock completely impossible bolt 5 is moreover provided with a groove 15 having a width at least corresponding to the width of the gap between door 2 and door jamb 4. Plate-like object 13 then comes to lie at the bottom of groove 15, whereby it has become impossible to exert a force in the direction of movement of bolt 5. In the case of an existing lock it is generally sufficient to replace the existing bolt with a bolt according to the invention, while the other components of the lock, such as mechanism 20, can remain unchanged. The transition from first rounding 14 to groove 15 is further preferably provided with a second rounding 16, wherein first rounding 14 and second rounding 16 together form a non-sharp rib.

[0017] Fig. 5A is a cross-sectional view of a prior art lock 1 together with a closing plate 18 at the moment door 2 drops into the locked position. Bolt 5 touches closing plate 18 here with its tip, whereby a couple also acts thereon in addition to an inward directed force, and this has an adverse effect on the friction and thereby on the wear of lock 1. Fig. 5B is a cross-sectional view of a lock 1 according to the invention at the moment door 2 drops into a locked position. Bolt 5 touches closing plate 18 here at a position far removed from the tip and at an advantageous angle, whereby the inward directed force is greater and the torque is smaller, whereby the bolt drops more easily into the lock and whereby the friction, and thereby the wear of bolt 1, are moreover favourably affected.

Claims

1. Lock, comprising a lock part for mounting in or on a door, in which a bolt provided with a bevelled side is slidably mounted, and a staple part or a closing plate for mounting against a door jamb provided with an opening into which the bolt drops when the door is closed, wherein the bevelled side of the bolt takes a relatively obtuse form such that the bevelled side is positioned at least substantially wholly inside the staple part or the closing plate when the door is closed, wherein a short side of the bolt is provided with a groove running at least substantially perpendicularly of a direction of movement of the bolt over a full width of the bolt, characterized in that
the groove (15) has in a transverse direction a concave, at least substantially half-round profile,
that a transition from the short side of the bolt (5) to the bevelled side (12) is provided with a first rounding (14), and
that an edge of the groove positioned close to the bevelled side (12) is provided with a second rounding (16) which is a continuation of the first rounding, wherein the first rounding and the second rounding together form a non-sharp rib.

2. Lock as claimed in claim 1, wherein the groove (15) has a substantially semicircular shape in a transverse direction.

3. Lock as claimed in claim 1 or 2, wherein the rib has a substantially semicircular shape.

4. Lock as claimed in claim 1, 2 or 3, wherein the bevelled side (12) has a substantially circular shape.

5. Lock as claimed in any of the foregoing claims, wherein a width of the groove (15) corresponds at least substantially to a distance between the lock (1) and the staple part (3) or the closing plate (18).

6. Bolt as described as part of a lock as claimed in any of the foregoing claims.

Drawing