Combination lock.

Technical field

The invention relates to a combination lock with a cast casing, a screwed on cover, a latch guided in the housing, the latch actuating a drive cam, a number of tumbler discs and a spring element, which blocks on removal of the cover the bars.

State of the art

a combination lock is known from US Patent 4,163,376, in which the bolt is blocked by a multiply bent lever. The lever bears in the central region a bearing point, which is articulated via a riveted pin to a housing projection laterally of the bolt guide. A lever arm presses against the lock cover, the other is with a hook through a recess in the located in the closed position bar. A guided on the bolt leg spring presses the lever against the lid.

Now, if an unauthorized person to lock lid wegschlägt after various manipulations by the spindle channel through it to get to the tumblers and to retract the bolt, it is thereby blocking that Sperrhe-bel incident under the force of the leg spring into the recess of the bar.

This three-part attachment bolt blocking is not only complicated and expensive, but it is also no perfect protection against forced entry. Namely, if the burglar is through the channel in a position to bring some tools, the tumblers in line, so it is him also slightly succeed, depress the adjacent to the tumblers lock lever to then finally withdraw the latch can.

In another combination lock similar design in the guide path of the bolt, a locking spring is provided, which is guided in a slot that is perpendicular to the bars path and to lock cover. When removed lock lid and the extended deadbolt lock spring is relaxed. It is then with its central region in the guide path of the bolt, so that it can not be retrieved with the help of the drive. The lock cover is at the point which is above the spring shaft, provided with a nose, which compresses the spring in the lid assembly. When fully assembled lock so the locking spring is outside the locking path. However, when the lid is knocked away with a break-in attempt takes place, the additional blockage of the bolt. Also with this lock the locking spring is exposed to such an extent that they can be felt and press down.

To complicate the scanning of the combination and the setting of the tumblers, it is from a publication of LA GARD further known to provide a separately fastened protective shield between the tumblers and the lock cover, which has such a large recess in the central region, that it does not can be knocked off the lid from the canal.

Summary of the Invention

The invention has for its object to provide an improved, inexpensive and not überlistbares combination lock that resists all attack attempts through the channel.

This object is achieved in that the housing has in the region of the guide path of the bolt a at the level of the lid perpendicular bore, that in this bore a resilient locking pin is guided, that this pin has a locking foot that this base of a recess of the extended bar facing and that the lid against the force of a spring out keeps the foot from the recess of the bar.

In a preferred embodiment, the locking pin is chosen so large that it does not protrude when the spring is over the upper limit level of the bolt guide channel.

DESCRIPTION OF THE DRAWINGS

An exemplary embodiment is based on Figure 1 - 4 illustrates the drawing..

<ul><li>FIG. 1 shows a longitudinal section through the partially illustrated combination lock with the lid,</li><li>FIG. 2 shows the same section with the lid removed,</li><li>Fig. 3 is a plan view of the open lock housing,</li><li>Fig. 4 shows another embodiment.</li></ul>

The section in Fig. 1 and 2, extends along the bent line A in Fig. 3.

In Fig. 1, the lock housing, preferably made by die-casting is designated by 1. In the right end side of the housing 1 of the block-shaped bolt 2 is mounted. Upwardly the housing is closed by the lid. 3 With 4 is designated a bore whose axis is perpendicular to the plane of the lid the third This bore is located partly in front of the locking surface, as FIG. 3 shows. The bolt guide channel in the housing 1 is thus cut from the hole. In the bore, a cylindrical locking pin S is used, the foot of which rests on a helical spring Sa 6th The spring 6 is pressed by an integrally formed pin 3a of the cover 3 downward. The locking pin 5 has in the region of the foot 5a and 5b of the head and has a larger in the central region has a smaller diameter. The bolt 2 is provided with a recess 2a, in which the foot 5a penetrates when the locking pin 5 when removing the lid 3 moves upward. The lid 3 is provided with a predetermined breaking point 3b indicated, which is annular to the spindle pin 9.

FIG. 1 shows the lock in the normal state, can be in which the latch 2 moves over the locking cams not shown any. If the cover 3 is forcibly removed through the spindle channel, the pin FIG. 2 jumps 5 corresponding to its blocking position, so that the bolt 2 by the foot Sa, acting as a locking nose, is securely blocked.

From Fig. 3 it is apparent that the distance s between the borehole axis and the bolt surface corresponds to the radius of the locking pin 5 in its central region. This locking pin can be manufactured as a turned part very reasonably priced. Also, the spring 6 is as a standard component extremely inexpensive. The bolt 2 is driven by the screw 8 and the incidence hammer, not shown. 10 with the tumbler discs are indicated. The recess 2, the pin 3a and the bore 4 can be realized as a simple geometric shapes with minimal tooling costs in the die.

The wall thickness of the bolt guide channel is so large that the pin 5 does not protrude when the lid removed 3 on the upper surface 1a. Therefore, the pin 5 can not be scanned or unlocked from the spindle channel 9 from.

The unlocking described is not only much cheaper than the known types, but it is in contrast to those also largely tamper-proof.

Fig. 4 shows the neck another safeguard: At the foot of the hole 4 a carbide ball 7 is pressed, which will prevent the targeted drilling out the lock pin. 5 Instead of the ball can also press in carbide tips to save towards a ball a few millimeters in height.

At each castle has several other points of the housing base on the vulnerabilities. Thus, the screw 8 is as endangered, which connects the latch 2 to the incident hammer, not shown. The same applies to the incident in the tumbler pin of the hammer. If the intruder knows the type of lock used, he can try using a template to control these weaknesses through the closet door pass. To stop this attack is also proposed to protect other lock bottom points through the use of cemented carbide bodies.

To prevent tampering with the tumbler, further measures may be taken to prevent the removal of the lock cover. It is very effective at the end of the spindle channel 9 provide an annular predetermined breaking point 3b in the lock cover. 3 When trying to chip away at the lid by the spindle channel through which material is removed at the predetermined breaking point, so that the tool comes into the void. The breaking point 3b in the lid 3 requires in current production no additions `set free. Your application makes it possible to dispense with the familiar shield, thus helping to further cheapening in.

The combination of different, very inexpensive protective measures makes it for the attacker is extremely difficult to overcome the lock, because he almost always can not know what precautions are taken. Incidentally costs trying different acts of aggression so much time, that increases the risk of a flagrant offense for him.

BEST MODE FOR CARRYING OUT THE INVENTION

The best way to implement the invention into practice is the fact that one so long selects the spring-loaded locking pin that it can not be felt with the spring relaxed. This is the case when the locking pin is flush with the surface of the bolt guide channel, so neither is still immersed.

Industrial applicability

The combination lock described can be used in all the money or valuables cabinets that have been equipped so far with no or only poorly protected castles. Subsequent installation is easily possible.

LIST OF REFERENCE NUMBERS

<ul><li>1 lock housing</li><li>1a upper boundary plane</li><li>1b lock housing bottom</li><li>2 bars</li><li>2a recess</li><li>3 cover</li><li>3a pin</li><li>3b breaking point</li><li>4 hole</li><li>5 locking pin</li><li>Sa foot</li><li>Sb head</li><li>6 coil spring</li><li>7 carbide ball</li><li>8 screw</li><li>9 spindle channel</li><li>10 tumbler</li></ul>