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Publication numberUS660230 A
Publication typeGrant
Publication dateOct 23, 1900
Filing dateApr 6, 1900
Priority dateApr 6, 1900
Publication numberUS 660230 A, US 660230A, US-A-660230, US660230 A, US660230A
InventorsJohn J Treat
Original AssigneeJohn J Treat
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 660230 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

No. 660,230. Patented Oct. 23, I900.



(Application filed Apr. 6, 1900'.)

(No Model.)




SPEGIFICATION forming part of Letters Patent No.

660,230, dated October 23, 1900.

Application filed April 6,1900. Serial No. 11,835. lNo model.)

the art may make and use the same.

The object of this invention is to simplify and cheapen the construction of locks of the class which require two or more keys to operate them, no one of the keys by itself being capable of so doing. The means by which this object is accomplished is shown in the drawings, in which Figure 1 is a view of the hack of a lock with some of the parts broken away to show the construction. Fig. 2 is an edge view of a lock. Fig. 3 represents the two sections of the key in side view, showing the difference in the bittings. Fig. 4 shows in edge view the two parts of the key together.

It is often advisable, when two or'more parties are interested in articles which are kept under lock and key. that the containing package or its lock be so constructed that the package cannot be opened without the presence of at least two of the parties concerned. The safety-deposit box is a case in point, it being customary for both the one who is responsible for the safe-keeping of the box and the owner to have keys, the lock being so constructed that .neither key will open the box without the aid of the other. Locks of this kind are generally known in the trade as guard-key locks, and this name will be used hereofter to designate such a lock. There are a number of locks uowin the market which fill the requirements, but they are very complicated and expensive. In many constructions now in use, I believe, two sets of tumblers are provided and are necessary, one set being operated by each key, and it is the general construction to have one key, called the guard-key, operate a lockin g device for the bolt of the lock proper, while the other key operates the bolt as soon as the lock-bolt is released. It will be evident to one familiar with the lock business that to make such a construction as is above suggested there are many difficulties to be overcome and that at the best the arrangement is bound to be intricate and the manufacture and assembling expensive. By the invention which I will now proceed to describe I have accomplished the desired results and am enabled to produce an effective guard-key lock extremely simple in construction and at a minimum cost.

Referring to the drawings, A denotes the case, B the bolt, C the tumblers, and D the key-guide, of an ordinary lock.

E is the fence on the bolt,which rests against the end of the tumblers 0 when the bolt is shot and travels back in the gating b in the tumblers when the bolt is withdrawn. This is all according to the ordinary construction of a lock of this class; but it is to be clearly understood that my invention is applicable to any and all descriptions of locks, the one illustrated being used because of its simplicity and adaptability for the purpose of illustration.

My invention consists, essentially, in a lock preferably havingbut one set of tumblers and a compound key H, made up of a series of elements M N, adapted to operate the tumblers of the look only when all of the independent elements are present and used simultaneously. Each section ofthe key has individual bittings,the total number of operative bittings on the several sections being equal in number to the number of tumblers in the look. It is preferable to usea key made up of not more than two sections, although it is evident that the number of sections is not essential to my invention. In appearance each section of this compound key is itself a key, having a handle, a shank, and bittings. In the key shown in Figs. 3 and 4 each section has individual bittings X Y, which are staggered with the bittings on the other sections, this being one of the many forms in which my invention may be used. Each section of the key has certain duties to perform, and these sections must always be used with a certain relation to one another, and in order to insure the proper positioning of the parts I place some kind of a guard,

such as the projection o, on one or more of the parts.

I claim as my invention- 1. A lock-bolt controlled by a single set of A lock-bolt controlled by a slngle set of tumblers mounted upon the same pivot in combination with a plurality ofindependent keys operative simultaneously side by side, the bittin gs of all of which together aggregate in number the number of tumblers in the lock whereby it is necessary to use the keys together to operate the look.

Signed this 31st day of March, 1900, at New 20 Britain, Connecticut.




Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4285574 *Nov 29, 1979Aug 25, 1981Neiman S.A.Device for reading coded notches on keys
US4875352 *May 11, 1987Oct 24, 1989Schlage Lock CompanyConstruction keying
DE2433918A1 *Jul 15, 1974Feb 5, 1976Voss Kg JSchluessel fuer zylinderschloesser
International ClassificationE05B19/06
Cooperative ClassificationE05B35/12