US3142168A

US3142168A - Lock protecting devices

Info

Publication number: US3142168A
Application number: US268143A
Authority: US
Inventors: John F Wellekens
Original assignee: HOTEL SECURITY SYSTEMS CORP
Current assignee: HOTEL SECURITY SYSTEMS CORP
Priority date: 1963-03-26
Filing date: 1963-03-26
Publication date: 1964-07-28
Anticipated expiration: 1981-07-28

Description

July 28, 1964 J. F. WELLEKENS 37,142,163

LOCK PROTECTING DEVICES Filed March 26, 1963 F|G.2. 7 FI IN VEN TOR.

John F. Wellekens United States Patent 3,142,168 LOCK PROTECTING DEVICES John F. Wellekens, New York, N.Y., assignor to Hotel Security Systems Corporations, New York, N.Y., a corporation of New York Filed Mar. 26, 1963, Ser. No. 268,143 4 Claims. (Cl. 70416) This invention relates to a protective device for locks and has particular reference to a device which will prevent locks from being broken open forthe purpose of robbery or illegal entry.

Parking meters, vending machines, storage boxes and many other compartments are provided with doors having cylinder type locks, and these locks are being constant ly broken open and the compartments containing money and other valuables pilfered.

A method commonly used by thieves in breaking open the locks is to insert a chisel in the keyhole of the lock and drive the chisel into the keyhole withhammer blows. A wrench is then attached to the chisel to enable the necessary leverage to be applied to twist the chisel, and the cylinder or barrel of the lock-is thus rotated to retract the bolt and permit of access to the interior of the compartment.

It is an object of the invention to provide a protective device which will prevent opening or breakage of a lock by the means above described or possibly by other means, whereby protection for the lock and the valuables guarded by it will result.

More particularly, the invention contemplates the provision of a lock having a forward extension containing a plurality of segments, rotatively mounted and defining a keyhole-like slot between them and through which a properly-contoured key may be inserted to reach the actual keyhole of the lock to manipulate the lock in the conventional manner. If a tool, such as a chisel for example, is inserted in the slot between the segments, such a tool will fail to reach and enter the actual keyhole of the lock and when the tool is twisted in an effort to break open the lock, it will merely rotate the segments. If the tool employed happens to be thin enough to extend beyond the segments and reach the keyhole of the lock, the thinness of the tool will cause it to break off when the force necessary to rotate the barrel in the lock is applied to the tool.

With these and other objects to be hereinafter set forth in view, I have devised the arrangement of parts to be described and more particularly pointed out in the claims appended hereto.

In the accompanying drawing, wherein an illustrative embodiment of the invention is disclosed,

FIG. 1 is an elevational view, with parts in section of a lock provided with the improved protective device;

FIG. 2 is a view of the slot closure means for the protective device;

FIG. 3 is a sectional view, taken substantially on the line 3-3 of FIG. 1, looking in the direction of the arrows;

FIG. 4 is a front elevational view of the device as seen from the left of FIG. 1;

FIG. 5 is a front elevational view of the two segments in the device;

FIG. 6 is a side elevational view of the segments, and

FIG. 7 is a view taken on the line 7-7 of FIG. 6,

3,142,168 Patented July. 28, 1964 other known parts of the lock are omitted since they are of known construction and are operated in the usual manner by rotation'of the lock plugjthrough the use of a properly fitting key inserted intothe keyhole 2. V The forward extension 3 of the housing 20 of the lock is internally threaded'as indicated at 4 and a cup-shaped member 5 is threaded into the extension 3 in the manner shown in FIG. 1. The cup-shaped member 5 maybe made in various lengths as desired and it is provided with a front flange 6, and the body of the cabinetor door therefor to which the lock is fitted, is clampingly maintained between the flange 6 and the forward end of theextension3. f

Mounted within the cup-shaped member 3 isv a pair of half-round segments indicated respectively at 8 and 9. These segments are made of hardened metal such as hardened steel and are mounted within the interior of the cup-shaped member 5 in amanne'r to permitth'e segments to be rotated relatively to the member 5. The segments have their opposing surfaces so shaped as to provide a slot-like opening 10 between them, simulating a keyhole and through which a lengthy, slender keyof proper shape may be inserted to reach and enter the keyhole 2 in the lock to open or close the lock. The'segments are notched as shown at 10a to conform to key shape. A closure plug 11 of cylindrical shape is disposed between the segments, the same being spring-biased by means of springs 12 arranged in pockets 13 provided in the segment 8. Said pockets communicate with a recess 14 provided in the segment 8 in which the plug 11 is located.

The spring-biased plug 11 tends to hold the segments apart, keeping them under slight pressure, and it also acts as a closure to keep dust and moisture out of the simulated keyhole. It is thrust aside by the entry of a key, the shank of which passes it and reaches and enters the keyhole 2 to operate the lock 1.

The

segments

8 and 9 are each formed with a forward, reduced diameter part 15 providing a shoulder 16, and this reduced diameter part fits within and rotates in the opening 17 in the flange 6, as clearly seen in FIG. 1. The shoulder 16 extends behind parts of the flange 6 and the segments are thus confined between the flange 6 and a retaining ring 18 confined in a groove 19 in the cup-shaped member 5.

From the foregoing, the operation of the lock protective device will be readily understood. The lock 1 is operated by means of a lengthy and relatively slender key of proper contour that is inserted through the

slot

10, 10a between the

segments

8 and 9, to reach and enter into the keyhole 2 of the lock 1. If the key thus entered is of the proper contour intended for the operation of the lock 1, the lock can be operated in the normal manner.

If an attempt is made to break the look by the insertion of a chisel or similar tool into the slot 10, the chisel being tapered, will not pass through theislot 10 to an extent to enable it to reach the keyhole 2. The thief will not be aware of that fact since the lock with the protective device attached presents, as will be seen in FIG. 4, the appearance of a conventional unprotected lock. Hence when he twists the chisel by means of a wrench or other leverage tool applied to it, and the chisel has only passed between the

segments

8 and 9 and has not reached the keyhole 2, he will be merely rotating the segments within their container 5, leaving the lock unaffected by his efforts.

If a lengthy, slender tool is entered into the slot 10 and such tool should be of a length to enable it to reach and enter the keyhole 2, the force required to rotate the barrel of the lock will be found to be such that the slender tool will break off and the theft will thus be frustrated. Since the

segments

8 and 9 are of hardened steel they will resist enlargement of the slot opening 10 by not becoming deformed, so that an attempt to drive a relatively thick tool between the segments by enlarging the slot opening between them will be prevented.

By means of the device described, the breakage of locks for the purpose of robbery or illegal entry will be prevented.

Having thus described a single embodiment of the invention, it is obvious that the same is not to be restricted thereto, but is broad enough to cover all structures coming within the scope of the annexed claims.

What I claim is:

1. A lock protective device comprising, a housing fitted at one end of a cylinder lock, said housing containing a plurality of separate segments rotatively mounted in the housing and defining a keyhole-like slot between them whereby a tool inserted in said slot in an effort to reach and enter the keyhole of the lock behind said housing to thereby apply a wrenching force to said lock will be prevented from reaching the keyhole of the lock and when such tool is rotated by applied force it will merely rotate the segments without affecting the lock.

2. A lock protective device as set forth in claim 1, wherein the segments are half-round hardened elements, and spring-biased means at least partly closing the slot between the segments.

3. A lock protective device comprising, a lock casing containing lock mechanism and including a keyhole, said casing having a forward extension, a cup-shaped member fitted into said extension, said cup-shaped member being open at its forward end, a pair of half-round segments rotatively maintained in the cup-shaped member and spaced apart to define a keyhole-like slot between them in the forward end of the cup-shaped member so that a key may be passed through such slot to reach the keyhole of the lock behind the segments, said segments being rotative within the cup-shaped member when a tool other than a proper key is thrust between them and turned in an etfort to reach and break the lock.

' 4. A lock protective device provided for in claim 3, with the segments so spaced forwardly of the front of the lock mechanism and the spacing between the segments being so narrow that only a long, slender tool can be used to reach the keyhole of the lock after passage between the segments and with the slenderness of such tool causing it to be of insuflicient strength to turn the lock plug without becoming broken while attempting to do so.

References Cited in the file of this patent UNITED STATES PATENTS Thompson July 25, 1882 Laughlin Mar. 12, 1912 Shinn Nov. 10, 1925

Claims

3. A LOCK PROTECTIVE DEVICE COMPRISING, A LOCK CASING CONTAINING LOCK MECHANISM AND INCLUDING A KEYHOLE, SAID CASING HAVING A FORWARD EXTENSION, A CUP-SHAPED MEMBER FITTED INTO SAID EXTENSION, SAID CUP-SHAPED MEMBER BEING OPEN AT ITS FORWARD END, A PAIR OF HALF-ROUND SEGMENTS ROTATIVELY MAINTAINED IN THE CUP-SHAPED MEMBER AND SPACED APART TO DEFINE A KEYHOLE-LIKE SLOT BETWEEN THEM IN THE FORWARD END OF THE CUP-SHAPED MEMBER SO THAT A KEY MAY BE PASSED THROUGH SUCH SLOT TO REACH THE KEYHOLE OF THE LOCK BEHIND THE SEGMENTS, SAID SEGMENTS BEING ROTATIVE WITHIN THE CUP-SHAPED MEMBER WHEN A TOOL OTHER THAN A PROPER KEY IS THRUST BETWEEN THEM AND TURNED IN AN EFFORT TO REACH AND BREAK THE LOCK.