Locks – Operating mechanism – Key
Patent
1989-03-21
1991-11-12
Wolfe, Robert L.
Locks
Operating mechanism
Key
70423, 70448, E05B 1516
Patent
active
050637657
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to locks and, more particularly but not exclusively, to a lock protector for a key operated lock. Although not restricted thereto, the present invention finds particular application in connection with motor vehicle ignition switch locks.
BACKGROUND
In the past, unauthorised persons have gained access to ignition switch locks in several ways. One such method entails the jamming of a key blank into the keyway of the lock and applying a force sufficient to rupture and turn the locking mechanism within the barrel, thereby operating the lock. Another well practised method of gaining illegal entry is to insert a self tapping screw into the keyway and then with the use of a screwdriver, apply enough force to rupture the locking mechanism and operate the lock. In general, a major disadvantage of present day locks, is the fact that objects other than the operating key may be inserted into the keyway and used to forcibly operate the lock.
It is therefore an object of the present invention to overcome or substantially ameliorate the abovementioned disadvantages.
SUMMARY OF THE INVENTION
In accordance with one broad form the present invention provides a lock protector adapted to protect the barrel of a key operated lock, said protector comprising a sleeve shaped to fit over said barrel, retaining means to secure said sleeve to said barrel against relative longitudinal movement therebetween, one end of said barrel having a keyway therein for operation of said lock, and the corresponding end of said sleeve having a keyway protector rotatably mounted therein and overlying said keyway, said protector having a narrow slot therethrough, the width of said slot and the distance between the outermost portion of said slot and said keyway being selected to permit the shank of the operating key to pass through the slot and into the keyway but prevent the insertion of objects other than the key into said keyway.
In a preferred embodiment, the retaining means comprises a non-return screw or break-off bolt. Preferably, the rotatable keyway protector would be mounted within the sleeve by way of a circlip arrangement, by means of chamfered edges or by a step or rebate configuration.
BRIEF DESCRIPTION OF THE DRAWINGS
Some preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:
FIG. 1 is an exploded perspective view of one embodiment of an assembled lock protector together with the lock;
FIG. 2 is the perspective view of the assembled lock and protector of FIG. 1;
FIG. 3 is a sectioned view of the assembly of FIG. 2 along line I--I;
FIGS. 4. 5 and 6 show in cross section further embodiments of the lock protector of the present invention together with the lock.
DETAILED DESCRIPTION OF THE DRAWINGS
In FIG. 1 there is schematically depicted a lock protector 1 together with a lock 2. The lock protector 1 comprises a sleeve 3 into which the lock 2 is able to be placed. As best seen in FIG. 3, lock 2 is held within the sleeve 3 by way of a non-return or break-off screw 4. If the lock 2 should be rotated within said sleeve 3, the screw 4 cuts a groove (not shown) into the outer circumference of the lock barrel or outer casing 17. This is mainly due to the relatively soft metal from which the lock barrel 17 is cast. Since the screw 4 will sit within the circumferential groove it cuts, the sleeve 3 is prevented from being withdrawn from the lock barrel 17 once secured in position.
A keyway 6 is located in the outer facing end 5 of the cylinder 18 of the lock 2. Overlying the keyway 6, and within the sleeve 3, is a keyway protector 7. In this embodiment, the keyway protector 7 is in the form of a disc mounted by way of a circlip 9, within the aperture 8 of the sleeve 3. As best seen in FIG. 3 the circlip 9 expands to partially occupy an annular groove 29 in the aperture 8 as well as a similar groove 39 in the disc 7. In this way the keyway protector 7 cannot be withdrawn from the sleeve 3 after ass
REFERENCES:
patent: 962276 (1910-06-01), Voight
patent: 1484831 (1924-02-01), Hurd
patent: 2049658 (1936-08-01), Moore
patent: 2225703 (1940-12-01), Machinist
patent: 3821886 (1974-07-01), Ladewig
patent: 4074552 (1978-02-01), Smith
patent: 4094177 (1978-06-01), Wellekens
patent: 4160368 (1979-07-01), Solow
patent: 4167222 (1979-09-01), El Bindari
patent: 4362035 (1982-12-01), Vitale
patent: 4446709 (1984-05-01), Steinbach
patent: 4490998 (1985-01-01), Wellekens
patent: 4662198 (1987-05-01), Scherbing
Squire Ian H.
Squire Ross D.
Dino Suzanne L.
Wolfe Robert L.
LandOfFree
Lock protector does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Lock protector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lock protector will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1005846