US3102412A - Tumbler lock with axially shiftable interchangeable tumblers - Google Patents

Description

Sept. 3, 1963 w. s. CHRISTOPHER 3,102,412

TUMBLER LOCK WITH AXIALLY SHIFTABLE INTERCHANGEABLE TUMBLERS Filed 001;. 25, 1961 //v VENTOR: WALTER 5. CHRISTOPHER ATT'X United States Patent 3,102,412 TUMBLER LOCK WITH AXIALLY SHIFTABLE INTERCI-IANGEABLE TUMBLERS Walter 5. Christopher, Park Ridge, Ill., assignor to Chitlrggo Lock Company, Chicago, 11]., a corporation of axons Filed Oct. 23, 1961, Ser. No. 146,778 1 Claim. (Q1. 70-363) The present invention relates to improvements in tumbler locks and has particular reference to tumbler locks of the type wherein the various tumblers associated therewith are axially shiftable with respect to the lock cylinder. In a lock of this general type, the tumblers slide in bores and pass from the stationary part of the lock into the rotatable part. Furthermore, the tumblers are transversely divided or split and are adapted to be longitudinally or axially displaced by the proper key for the lock against the resistance of springs in such a manner that their splits or joints coincide with the joint between the movable and stationary parts of the lock. For that purpose, the key which controls the lock is provided with an annular series of push pins or other protuberances of unequal but definite or predetermined length, the various lengths of the push pins being commensurate with the extent to which their associated or respective tumblers must be forced back into the pinreceiving bores of the lock so that all of the joints of the tumblers will conicide with the joint between the stationary and rotatable parts of the lock and thus permit the rotatable part to be turned by the key.

In my copending patent application Serial No. 127,584, filed on July 28, 1961, and entitled Adjustable Key and Assembly Jig Therefor, there has been disclosed a key for locks of the character briefly outlined above and wherein the push pins are interchangeable in their respective mountings to the end that the number of effectively different keys which may be constructed for use with difierent combinations of tumblers, while utilizing the same key parts, will be governed by the mathematical law of all possible permutations. The key is designed primarily for use in elfecting quick and easy changeover operations as, for example, by the field operator of public vending machine cabinets where the change-over may be made at the scene of any given installation and without requiring either the services of a work bench or special tools, as well as dispensing with the necessity of conducting extensive dismantling operations of the key assembly. The present tumbler lock has been designed as a counterpart of the key shown and described in the hereinbefore mentioned patent application in that it also is capable of quick and easy change-over operations by a field operator. Thus, when employed as a vending machine cabinet lock, for example, the same field operator, at the time he efiects a change-over of the key combination, may also effect a commensurate or corresponding change-over operation on the counterpart look so that the combination of both the lock and key will agree and become effective for cabinetlocking and unlocking operations, both change-over operations being readily performed in the field at the scene of the installation and without requiring extensive dismantling of either par-t.

Present day changeable combination locks of the character under consideration herein are possessed of at least one serious limitation in that it is extremely difficult to effect a change-over operation of the combination in the field. Ordinarily, it is necessary to remove the lock from its mounting and to thereafter remove the core or barrel from the lock cylinder and otherwise almost completely dismantle the assembly. Not only are special tools required for these dismantling operations, but a 3,i2,4l2 Patented Sept. 3, 1963 suitable work bench or table is necessary. It also is desirable that a container or tray be provided to hold the parts while the lock assembly is dismantled.

The present invention is designed to overcome the above-noted limitation that is attendant upon the con struotion and use of conventional changeable combination tumbler locks and, accordingly, it contemplates the provision of a novel lock assembly having axially shiftable split tumblers which are longitudinally slidable in the lock cylinder and in which the tumblers are removable from the cylinder in which they are slidable through the rear end of the latter so that it is not necessary to remove the cylinder from the barrel in which it is rotatable. Since the tumblers are removable through the rear end of the barrel, and since the latter is normally exposed on the inside of the door or other panel on which the lock is installed, it is not essential that the cylinder, i.e., the entire lock assembly, be removed from its mounting when change-over operations are effected.

The provision of a tumbler lock wherein change-over operations may be effected in a simpler manner and with considerably greater dispatch than has heretofore been possible with other locks designed for the same purpose being among the principal objects of the invention, it is a further object to provide such a lock wherein the only tool required for elfecting the change-over operation is a pair of jewelers tweezers or a similar tool.

The provision of a lock of this character which is comprised of a minimum number of pants and which, therefore, is unlikely to get out of order; one which is rugged and durable and which, therefore, will withstand rough usage; one which is simple in its construction and which, therefore, may be manufactured at a low cost; and one which otherwise is well adapted to perform the services required of it, are further desirable features which have been borne in mind in the production and development of the present invention.

In the accompanying single sheet of drawings forming a part of this specification, one illustrative embodiment of the invention has been shown.

In these drawings:

FIG. 1 is a perspective view of an adjustable key designed for cooperation with the adjustable lock of the present invention;

FIG. 2 is a front perspective view of the adjustable lock;

FIG. 3 is a rear end elevational view of the lock;

FIG. 4 is afragmentary sectional view taken substantially along the line 44 of FIG. 3;

FIG. 5 is a sectional view similar to FIG. 4, with a portion of the 'view being exploded and, with other portions being broken away, and illustrating the manner in which change-over operations may be effected; and

FIG. 6 is a rear elevational view of the lock with certain portions broken away to more clearly reveal the nature of the invention.

Referring now to the drawings in detail, a lock constructed in accordance with the principles of the present. invention has been designated in its entirety at 10 and it includes a lock cylinder 12 within which there is disposed a sleeve-like rotatable part 14 and a non-rotatable sleeve-like part 1-6. The fixed part :16 is maintained within the cylinder 12 against relative rotation by means of a radial pin 17 (see FIG. 4). An annular series of split tumblers 18, each including a driver pin 20 and a spring-pressed follower pin 22, are slidable longitudinally in respective bores in the two parts. The tumblers are adapted to be longitudinally displaced by the key which has been shown in FIG. 1 and designated in its entirety at 24 and when they are so displaced'that all of the joints or splits 26, therefore, are in transverse register with the interfacial plane between the two par-ts,

3 the rotatable part 14 may be turned within the lock cylinder in the usual manner of key operation. The splits are at different longitudinal locations.

The lock cylinder has an inwardly extending front flange 30 which is provided with a radial notch 32 for entry of an external guide lug 34 on the key 24, and a diametrically opposed radial notch 36 for removal of the guide lug "34 and withdrawal of the key when the rotatable part 14 has been turned in its unlocked position. A pilot post 38 is movable with the rotatable part 14 of the lock and cooperates with the key 24 in a manner that will be made clear presently in order to facilitate proper entry of the key 24 into the lock cylinder.

Reference may be hadto the above-mentioned patent application Serial No. 127,584 for a full disclosure of the construction and operation of the key 24 of FIG. 1, but for purposes of description herein and to show the relationship which the key bears to the lock it is deemed suflicient to state briefly that the key involves in its general organization an annular series of push pins 48 for actuating the tumblers 1-8 of the lock 10. The push pins 40' are of unequal length and they are adapted to be selectively and interchangeably received in a series of longitudinally extending grooves 42 provided in the outer surface of a cylindrical tubular push pin holder 44. The pins fit snugly within the grooves 42 and, when assembled therein, the holder and pins are received within a socket provided in the cylindrical body portion 46 of the key. They are locked in position within the socket by means of a fastening bolt 48. An internal drive lug 50 on the holder cooperates with a notch 52 in the pilot post 38 as a preliminary to unlocking the lock 10. After insertion of the key into the lock, the lug 50 and the notch 52 form a driving connection whereby the key and rotatable part 14 are locked together for conjoint turning movement.

The various push pins 40' are of unequal length and, consequently, they are positioned within the grooves 4 2 with the forward ends thereof being positioned at different longitudinal distances from the forward rim of holder 44. Thus, when the key is inserted into the lock, the ends of the push pins engage the forward ends of the split tumblers 18 and slide the tumblers rearwardly into their lock-releasing position wherein their splits coincide with the interfacial plane between the rotary and stationary lock parts 14 and 16., respectively, and then permit the rotatable part to be turned by the key relatively to the stationary part.

As previously stated, the various push pins 40 are interchangeable in the grooves 42 and, in order to effect change-over operations, in; is merely necessary to remove the fastening bolt 48 and slide the holder 44 and its contained push pins 40 from the socket provided in the cylindrical body portion 46'. The push pins 40 are then in an exposed position whereby they may readily be selectively interchanged according to any desired contemplated permutation.

It is obvious that when a given change-over has been made in the arrangement of the push pins 40 of the key 24, a corresponding change-over must be effected upon the tumblers 18 of the lock 10'. According to the present invention, such a change-over operation may be effected in a simple and easy manner by reason of the way in which the tumblers 18 are made accessible for removal from the rear end of the lock cylinder 12. Accordingly, the rear open rim region of the cylinder 12 is formed with an internal narrow annular groove 60 within which there is adapted to be seated a removable expansible and contractible split locking ring 62, which, when in position within the groove, serves to maintain a backing ring 64 in position within the central bore 66 within which the rotatable and non-rotatable parts 14 and 16, respectively, are mounted. The backing ring 64 is provided for the purpose of assimilating the reaction force of a series of springs 68 by means of which the split tumblers 18 are forced forwardly within respective small bores 70 and 72 provided in the parts 14 and 16,,respeotively. In the locked condition of the lock 18, the various bores 70 and 72 remain in axial alignment or register but with the various splits 26, or at least one of them, out of register with the interfacial plane between the two parts :14 and .1 6. In the unlocked condition of the lock 10, all of the splits 26 are in circumferential alignment with one another, as well as with such interfacial plane, as is customary with locks of the axially movable tumbler type. The springs 68 serve to move the various tumblers 18 forwardly within the aligned bores 70 and 72 when the latter are in respective alignment.

The previously mentioned pilot post 38 forms part of a central plug 74 which projects rearwardly beyond the rear rim of the cylinder 12 and is provided with a reduced extension 76 having flattened sides 78, the reduction in diameter affording an annular rearwardly facing shoulder 80 on the plug 74. A stop cam 82 seats against the shoulder 80 and has a pair of oppositely directed shoulders 84 and 86 (see FIG. 6) designed for engagement with a stop lug 88 formed on the cylinder 16 to limit the extent of rotational movement of the rotatable lock parts in opposite directions respectively. A lock washer 90 is disposed forwardly of the stop lug 88 and a radially extending locking plate 92 is carried on the extension 76 rearwardly of the lock washer 90. A nut 94 is threadedly received on the extension 76 and serves to maintain the stop cam 82, washer 90 and locking plate- 92 in position on the threaded extension 76. The extension is .formed with oppositely facing flat sides 78 and a fiat sided recess 98 is formed in the locking plate for reception of the extension so that relative turning movement between the two parts is precluded. The locking plate 92 thus receives its turning movement under the influence of the key 24 which drives the plate through the medium of the cooperating drive lug 50', notch 52, pilot post 38 and pl g 74.

When it is desired to eifect change-over operations on the lock 10, it is merely necessary for the operator to remove the nut 94 and lift the locking plate 92 from the end of the extension 76 on the plug 74 after which, by the aid of a pair of tweezers or pliers of the needle nose variety, to contract the split locking ring 62 and withdraw the same from the groove 60 so as to release the backing ring '64 which also may be withdrawn from the cylinder 12. To facilitate removal of the locking ring 62, the adjacent ends thereof in opposite sides of the split therein are enlarged and provided with entry holes 100 for reception of the ends of the tweezers or pliers jaws preparatory to contraction of the ring. After the backing ring 64 has been removed, the ends of the various springs 68 are exposed from the rear open end of the lock and they may be pulled from their respective bores 72, utilizing the same tool which was employed for releasing the split locking ring 62. Upon removal of the springs 68, the follower pins 22 are accessible for removal and, thereafter, access may be had to the driver pins 20.

In thus removing the tumblers 18 for interchange purposes, the entire lock assembly may be removed from the cabinet door or other installation with which it is incorporated, but it is not essential that such removal be effected. The lock cylinder may be left in position in the installation and, after the springs 68 have been withdrawn from the lock cylinder 12, the tumblers may be rendered accessible through the rear open rim of the cylinder simplyby inserting the point of the tool through the open front rim of the cylinder and pushing the tumblers rearwardly so as to expose the rear ends thereof.

It has been previously stated that change-over operations ordinarily will be made upon a key 24 and its mating lock 10 by the same operator at the scene of installation. It is obvious that when such a dual change-over operation is made, the position to which any given push pin 40 in the key 24 has been moved must be accompanied by a corresponding positioning of the corresponding tumbler in the lock. To assist the operator in effecting such correlation between push pins and tumblers, colored indicia may be employed on the pins and tumblers, for example, by the application of daubs of identically colored lacquer to the pins and tumblers which correspond to each other. It is not necessary to remove all of the tumblers at one time in effecting a change over operation. As soon as one tumbler has been removed, another tumbler may be extracted from the cylinder and deposited in the place originally occupied by the first removed tumbler. Thus, at no time is the operator obliged to keep track of more than the parts associated with the particular tumbler with which he is dealing at any given instant.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawing or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit of the invention. Therefore, only insofar as the invention has particularly been pointed out in the accompanying claim is the same to be limited.

Having thus described the invention what I claim as new and desire to secure by Letters Patent is:

In a tumbler lock of the character described, a lock cylinder having an axial bore extending therethrough and provided with an open front rim for insertion of a key therethrough and an open rear rim, an annular sleeve-like front rotatable part and an annular sleevelike fixed part disposed within said bore and presenting relatively slidable faces which meet each other on an interfacial plane normal to the axis of the cylinder, a plug projecting through said rotatable and fixed parts and having a portion thereof extending rearwardly outwardly through the 1OPI1 rear rim of the cylinder, means securing the plug and rotatable part together for rotation in unison, a series of longitudinally extending bores termed in said fixed part and arranged in circumferentially spaced relationship therearound, a similar series of longitudinally extending bores tformed in said rotatable part and similarly arranged therearound, said rotatable part being movable between a position wherein the respective bores of the two parts are in alignment and the lock is in its locked condition and a position. wherein such bores are out of alignment and the lock is in its unlocked condition, a split tumbler assembly for each pair of aligned bores including a driver pin slidable in the respective bore of the rotatable part and a follower pin slidable in the respective bore of the fixed part, a spring disposed in each bore of the fixed part rearwardly of the ifollower pin therein for normally urging the latter rforwardly, the rearwardly extending portion of the plug being of reduced diameter and thus defining a rearwardly facing shoulder on the plug, a stop cam surrounding the rearwardly extending portion of the plug and seating against said shoulder, said stop cam being disposed exteriorly of the cylinder and rear-wardly of the backing ring, said stop cam being provided with a pair of ciroumferentially opposed stop shoulders thereon, a stop lug formed on the rear end face of the cylinder and interposed between said stop shoulders on the stop cam, a backing ring disposed within said bore in the cylinder rearwardly of said springs for assimilating the rearward thrust of the latter, said bore in the cylinder being formed with an internal annular groove therearound adjacent to the rear rim thereof, and a removable split locking ring disposed within said groove and having its inner periphery projecting inwardly of the bore, the radial extent of said backing ring being greater than the radius of said inner periphery of the locking ring whereby the backing ring is effectively retained within the bore in the cylinder when said locking ring is in position within said groove.

References Cited in the file of this patent UNITED STATES PATENTS 1,968,555 Home July 31, 1934 2,557,028 Deutsch June 12, 1951 2,993,361 Van Lahr July 25, 1961 FOREIGN PATENTS 504,473 France Apr. 15, 1920 424,800 Italy Sept. 2, 1947 445,596 Italy Feb. 18, 1949

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