US3903720A

US3903720A - Axial lock and key

Info

Publication number: US3903720A
Authority: US
Inventors: Frank J Scherbing
Original assignee: SECURITY DEVICES Inc
Priority date: 1970-05-15
Filing date: 1973-01-30
Publication date: 1975-09-09
Anticipated expiration: 1992-09-09

Abstract

An axial pin tumbler lock, as disclosed, has a stationary barrel encircling a rotary spindle to define an annular pin chamber that is accessible through an annular key entry passage that has a very narrow transverse gap that acts to prevent unauthorized opening or picking of the lock. The spindle carries a rotary collar to transmit the lock opening torque and to hold a set of code pins in a symmetrical array. Only an eccentric portion of each pin is accessible through the narrow key entry passage. In addition, there is provided a rotatable eccentrically mounted key guide which further aids in preventing the lock from being picked. The guide is so designed that in the event an attempt is made to pick a single pin, the guide is rotated to a position preventing access to a number of the other pins. Also, the lock could include letter code pins which would further minimize the space in which a lock picker could work. Furthermore, provision is made for providing for a positive lock in the event a code pin is moved past its breaking point. The lock has no keyways or keying lugs, so there is no structure other than the code pins for delivering torque to the lock shaft. A mating composite key has a key holder carrying a key cartridge that is end slotted according to the coding for the pins. The key holder is cross-coded with the lock and receives the key cartridge in predetermined rotary position to control the correct point of entry for the key cartridge and the key abuts against the lock barrel to determine the correct depth of insertion. Also, as a further embodiment, there is provided an axial pin tumbler lock including a sleeve containing one or more projections whereby the setting of the lock can be changed without necessitating the removal or replacement of any of the parts of the lock.

Description

[451 Sept. 9, 1975 AXIAL LOCK AND KEY Frank ,I. Scherbing, Niles, ill.

[73] Assignee: Security Devices Incorporated, Chicago, 111.

[22] Filed: Jan. 30, 1973 [21] Appl. No.: 328,112

Related 1.1.5. Application Data [63] Continuation-impart of Ser. No. 37,686, May 15, 1970, which is a continuation-in-part of Ser. No. 620,784, March 6, 1967, abandoned.

[75] inventor:

[52] US. Cl. 70/363; 70/382; 70/454 [51] Int. Cl E051) 27/08 [58] Field of Search 70/363, 383, 382, 454, 70/384, 385

[56] References Cited UNlTED STATES PATENTS 2,170,205 8/1939 Lombardo 70/363 3,339,384 9/1967 Greenwald 70/363 3,648,492 3/1972 Walters 70/363 FOREIGN PATENTS OR APPLlCATlONS 534,215 1/1922 France 70/363 Primary Examiner-Robert L. Wolfe Attorney, Agenl, 0r Firm-Dressler, Goldsmith, Clement & Gordon, Ltd.

57 ABSTRACT An axial pin tumbler lock, as disclosed, has a stationary barrel encircling a rotary spindle to define an annular pin chamber that is accessible through an annular key entry passage that has a very narrow transverse gap that acts to prevent unauthorized opening or picking of the lock. The spindle carries a rotary collar to transmit the lock opening torque and to hold a set of code pins in a symmetrical array. Only an eccentric portion of each pin is accessible through the narrow key entry passage.

in addition, there is provided a rotatable eccentrically mounted key guide which further aids in preventing the lock from being picked. The guide is so designed that in the event an attempt is made to pick a single pin, the guide is rotated to a position preventing access to a number of the other pins. Also, the lock could include letter code pins which would further minimize the space in which a lock picker could work. Furthermore, provision is made for providing for a positive lock in the event a code pin is moved past its breaking point.

The lock has no keyways or keying lugs, so there is no structure other than the code pins for delivering torque to the lock shaft. A mating composite key has a key holder carrying a key cartridge that is end slotted according to the coding for the pins. The key holder is cross-coded with the lock and receives the key cartridge in predetermined rotary position to control the correct point of entry for the key cartridge and the key abuts against the lock barrel to determine the correct depth of insertion.

Also, as a further embodiment, there is provided an axial pin tumbler lock including a sleeve containing one or more projections whereby the setting of the lock can be changed without necessitating the removal or replacement of any of the parts of the lock.

3 Claims, 32 Drawing Figures PATENTEBSEF SHEET 1 [IF 8 W IN l/E N TOR $2M, W M M ATTORNEYS PATENTEDSEP' 1915 SHEET 2 BF 8 NVENTOR mag kvwg QM, M MgM ATTORNEYS PATEHTEU 5E? 9|975 3. 903 72D SHEET 3 ur a INVENTOR ATTORNEYS PATENTED SEP 9 I975 SHEET B U? 8 AXIAL LOCK AND KEY This application is a continuation-in-part of Scherbing application Ser. No. 37,686, filed May 15, 1970, which is a continuation-in-part of Ser. No. 620,784,

filed Mar. 6, 1967, now abandoned, both of which are assigned to the assignee of the present application.

This invention relates to a lock and key system employing an axial tumbler-type lock structure and a composite key assembly comprising a key holder and a key cartridge.

The most commonly used axial pin tumbler lock now employs an asymmetrical seven-pin array carried in a pin mounting collar that is rigid with a center spindle, which serves both as a lock shaft and as a front pilot post. A mounting barrel encircles the pilot post in spaced relation to define an annular key entry passage large enough to receive a key. A one-piece tubular key is used, the key having a scalloped transverse sectional configuration coded to fit between the pilot post and the pins and to bottom against the pin mounting collar. These relationships result in an unduly wide entryway through which the pins are easily accessible. Moreover, the pilot post has a keyway, so that torque can be applied directly to the spindle leaving the pins easily settable to breakaway depth. In some form, a keyway is also provided in the barrel to define the proper point of entry, though visual inspection of the asymmetrical array easily reveals the point of entry.

The described structure is easy to pick and a picking tool, such as shown in Gruber US. Pat. No. 3,251,206, has proven this to the point where new lock designs are now being proposed. One specialized lock structure intended to overcome the problem is shown in Kerr US. Pat. No. 3,267,706, which uses a symmetrical array of code pins, masks the code pins, and relocates the keyway through which torque is applied to rotate the spindle.

The prior art includes earlier patents on locks using symmetrical pin arrays and masking (see Barrett US. Pat. No. 1,494,765 and Falk U.S. Pat. No. 1,891,214), but these are also easy to pick and do not solve the problem.

Other drawbacks to the prior art lock and key system include restricted total code capacity, limitation in master keying, dependence upon maintaining security in the control of the key distribution and ease of reading and creating substitutes of the code keys. Also, such prior art systems are limited to a single key setting and the setting cannot be changed without dismantling the lock and replacing or shifting various internal part thereof.

The present invention provides a lock and key system which overcomes the problems described herein. The lock structure is not subject to picking by any conventional devices or techniques, and the opening setting can be quickly and easily changed by a special key. The key is of a construction that requires extensive fabrication and machining operations and is very difficult to duplicate.

In accordance with the present invention, there is provided an axial tumbler lock which includes a rotary holder carrying a set of lengthwise shiftably mounted forwardly projecting code pins spaced about and parallel to an axis of rotation for the holder and a lock shaft drivingly engaged for operation by rotation of the holder. It further includes means normally blocking the holder against rotation, which means are responsive upon predetermined lengthwise shifting of each code pin to release the rotary holder, and other means disposed forwardly of the holder and defining a lengthwise key entry opening that permits access to an eccentric peripheral region of each pin for effecting torquing of the rotary holder, the last-named means being free of structure for effecting torquing of the rotary holder.

[11 one illustrated embodiment, the holder is made in two pieces, the outer one of which is eccentrically mounted within the other. When the breakaway depth of the code pins is reached, the second or rear portion of the holder will be rotated to affect opening of the lock.

One of the features of the lock structure resides in the masking mounting of the code pins adjacent the spindle, so that only the interpin spaces are accessible for insertion of a pick. in particular, only eccentrically disposed pin regions which define a wedge-shaped pocket are accessible. Thus, any pick that can be inserted for applying torque to a pin engages the pin eccentrically to result in canting of the pin causing the pick to become wedged between the pin and spindle, so that the pin becomes bound and is not free to be shifted as necessary to set it to breakaway position.

The insertion of the pick further acts to rotate the eccentrically mounted portion of the holder which moves it into position to block a number of the code pins from being accessible from the exterior of the lock.

in addition, if desired, letter code pins can be interspersed between the locking code pins, which further minimizes the accessibility of the locking code pins to a picking tool. These letter code pins also provide for numerous additional code combinations.

An axial tumbler lock and key combination in accordance with this invention utilizes a lock structure having a symmetrical array of code pins recessed in a key entry passage that exhibits no fixed point of entry and utilizes a key cartridge having a coded end enterable through the passage to engage and set the pins to breakaway condition only when the key cartridge is disposed at a predetermined entry point and is advanced to a predetermined depth of insertion determined by a shoulder of the cartridge, and a key holder mounting the key cartridge in a predetermined relationship to establish the proper entry point for the cartridge.

To obtain additional code combination, an undercut pin is provided adjacent the lock opening and a slot is cut into the shoulder on the key. The slot permits entry of the key when a pin is provided and after the key is inserted, the shoulder prevents the key from being removed from the lock until it has been re-locked. However, two appropriately spaced notches can be provided if it is desired to permit the key to be removed when the lock is in the open position.

Another feature contained in the present lock is the use of one or more locking pins which when moved a predetermined distance by someone attempting to pick the lock engages the cam plate, which prevents opening of the lock.

In a disclosed embodiment, the lock of this invention is represented as a conventional type suitable for use in existing lock mountings. Alternative embodiments are also disclosed for illustrating other lock constructions incorporating the concepts of the present invention.

In a further embodiment, there is provided a lock having a three-member movable holder assembly and a collar member having one or more projections which can be rotated to readily vary the opening setting of any given lock. The three pieces above referred to include an outer freely rotatable holder, an inner member connected to the locking element, and an intermediate member which permits resetting of the opening setting of the lock without disturbing the inner member connected to the locking element.

As previously mentioned, interference structures, such as letter code pins, provided in one or more of the interpin spaces enable even more code combinations to be developed from a single code pattern. Thus, a key cartridge coded to control a particular code pattern that must be inserted a prescribed distance for properly setting the code pins must also include a coded slot contour that can accommodate the interference structure.

Other features and the advantages of the invention will be apparent from the following description and claims, and are illustrated in the accompanying drawings which show an illustrative embodiment of the present invention.

In the accompanying drawings forming a part of the specification, and in which like numerals are employed to designate like parts throughout the same,

FIG. I is an exploded perspective view showing one embodiment of a lock and key combination constructed in accordance with the present invention;

FIG. 2 is a front elevational view of the lock assemy;

FIG. 3 is a lengthwise section through the lock assembly and is taken on the line 3-3 of FIG. 2;

FIG. 4 is a rear elevational view of the lock assembly;

FIG. 5 is a perspective view of a composite key comprised of a key holder and a key cartridge;

FIG. 6 is a side view. partly in elevation and partly in section, showing the key fully assembled;

FIG. 7 is an end view showing the key assembly;

FIG. 8 is an enlarged developed sectional view taken approximately in the circular plane of the line 88 of FIG. 2 and showing the end of a matching key cartridge in approach relation thereto;

FIG. 9 is a view like FIG. 8 and showing the key fully inserted to locate the pins at their breakaway position;

FIGS. 10 and 11 are related greatly enlarged fragmentary front elevational views illustrating the pin mounting relationship when subjected to a typical pick;

FIGS. 12 to 15 are lengthwise sectional view showing a number of alternative lock structure incorporating certain features of the invention;

FIG. 16 is a developed sectional view like that of FIG. 8 and showing additional coding and master keying features including a fixed post interference structure and stub pin coding;

FIG. 17 is a developed sectional view duplicating the lock of FIG. 16 but showing a different key coded as a master;

FIG. 18 is a developed sectional view showing an other form of coding including loose letter code pinstype of interference structure;

FIG. 19 is a fragmentary diagrammatic plan view illustrating a display panel mounting an array of locks set up according to certain master coding systems used in the practice of the invention;

FIGS. 19A to 19F are enlarged views of certain of the differently coded individual locks shown in the array of FIG. I9;

FIGS. 20 and 21 are partially developed views of an embodiment incorporating an anti-indexing feature;

FIG. 22 is an exploded perspective view showing another embodiment of a lock and key combination in which the setting can be changed without having to remove or replace any parts;

FIG. 23 is a front elevational view of the embodiment shown in FIG. 22;

FIG. 24 is a lengthwise section through the lock assembly and is taken on the line 24-24 of FIG. 23;

FIG. 25 is an exploded elevation view of the threepiece holder assembly; and

FIG. 26 is a plan view of the holder assembly shown in FIG. 25.

Referring now to the drawings, a key and lock arrangement constructed in accordance with the present invention is illustrated in detail in the exploded view of FIG. 1 which represents a conventional form in that it is suited for installation in existing lock mountings. The key assembly 20 is shown in greater detail in FIGS. 7, 8 and 9 and is of a compostie construction having a key holder 21 for mounting a key cartridge 22 which is pictured facing an entry passage in FIG. I. The key cartridge is secured to the key holder by a screw 25.

The lock 30, as represented in FIGS. 1 to 4, includes a stationary barrel 3] of standardized form having a threaded main sleeve portion 32 terminating in a flanged facing portion 33 which presents an internal annular shoulder 335. A two-piece spindle 34 is jounrnaled in a stationary pin collor 35 to provide a subassembly that is insertable through the rear end of the lock barrel 3]. The stationary collar 35 is located and fixed within the rear of the lock barrel 31 by means of a lock screw 36 that extends through tapped

holes

31H and 35H, respectively, in the barrel and collar walls. The spindle 34 has a front end portion 34? which projects toward the front of the barrel 3].

The spindle portion 34F shown in elevation has a head portion 34A and a stem portion 343, which stem portion is mounted in a cylindrical opening 34C drilled into the intermediate cylindrical portion 34D of the spindle 34. The axis of the cylindrical opening 34C is spaced from the axis of the cylindrical portion 34D, whereby upon rotary movement of the fron end portion 34P, the head portion 34A will move into a position that covers several of the code pins to prevent picking thereof (see FIG. 2). It is to be noted that the head portion 34P is tapered at 34E, which permits rotation of the head portion 34P, during which rotation the adjacent code pins are cammed inwardly by the tapered surface 34E. The head portion 34? is retained in placed relative to spindle portion 34D by a locking pin 40. The pin 40 fits into an annular groove 34F defined by the stem portion 34B, which permits rotation of the stem 34B relative to the portion 34D.

Referring to FIG. 2, there is shown the head portion 34F in a rotated eccentric position in which position it blocks off access to the pins located in the lower right region of the lock.

The spindle has a non-circular rear end 348 projecting beyond the rear of the barrel to serve as a lock shaft for mounting a cam stop washer 37, a locking cam 38 and the usual shaft washer 39W and lock nut 39N. The spindle 34 includes an enlarged intermediate collar portion 41 which is fixed to and rotatable with the spindle portion 34D under the control of a symmetrical array of tumbler assemblies.

Each tumbler assembly includes an interlock pin 42 seated against a bias spring 43 that is recessed in a pin base 353 in the stationary collar. Each interlock pin 42 normally is resiliently urged towards a forward position projecting into the rotary collar 41 to prevent rotation of the collar unless all interlock pins are flush with the breakaway face of the stationary collar 35. Finally, each tumbler assembly includes a lengthwise shiftably mounted forwardly projecting code pin 44 carried in the collar 41 to be keyed to proper depth for controlling positioning of the corresponding interlock pin to breakaway position. Thus, the collar 41 serves as a rotary holder carrying the array of code pins 44.

In the preferred embodiment shown in FIG. 3, one or more of the tumbler assemblies may include a roller bearing 49 disposed between the code pin 44 and the interlock pin 42. The use of such a bearing makes is increasingly difficult for someone picking the lock to detect when the bearing is at the breakaway position, since there is no sudden change due to the spherical surface of the bearing. Actually, someone attempting to pick the lock will tend to move code pin 44 to the breakdown position, in which position the lock will be held against being opened, as set forth in the following paragraph.

As an additional feature which prevents picking of the lock, there are provided locking members in the form of one or more elongated stems 42A that extend through their respective springs 43 and cylindrical hole 35C to the exterior of the collar 41. Cylindrical hole 35C is in alignment with a corresponding cylindrical hole 37A in the cam stop washer 37. Thus, it can be appreciated that when the code pin 44 is depressed to move the bearing 49 past the breaking position of the lock, the elongated stem 42A will move outside of the barrel and into the hole in the opening 37A in the cam stop washer 37. In this position, it will be apparent that the lock cannot be opened since it is physically held against movement by the interrelationship between the stern 42A and the locking plate 37. As shown in FIG. 1, the cam stop washer is formed with eight holes and, similarly, one or more of the code pins 42 can be provided with elongated stem portions with the result that up to eight mechanical interlocks could be provided.

As is best seen with reference to FIGS. 1 and 3, the forward end of the barrel provides surrounding wall structure 33W to encircle the forward end 34! of the spindle, which end provides a freely rotatable pilot post structure cooperating with the surrounding wall structure 33W to define an annular key entry passage 45 opening into an annular mounting chamber 46. In the embodiment shown in FIGS. 1 to 4, the pilot post structure 34F is cylindrical and is located inwardly of the front surface 31A of the barrel 3]. The barrel 31 has an internal peripheral flange 31F providing the annular internal shoulder 33S masking the major portion of the mounting chamber 46 and masking the major portion of each code pin 44. Thus, the barrel flange 31F projects toward the pilot post 34? to provide a key entry passage 45 having a minute transverse gap dimension limiting access to the code pins 44. In addition, each code pin 44 is located immediately adjacent to the pilot post structure 34F to eliminate any discernible clearance gap between the pilot post structure and each code pin. As is most graphically seen in FIG. 2, the annular key entry passage 45 affords access only to a limited peripheral region of each code pin, this region being offset from or eccentric to the circular locus L (see FIG. 2) on which the axes of the array of code pins are located. Since the spindle torquing forces as applied through the code pins can only act at these eccentric pin regions, a canting effect necessarily results, tending to tilt the code pin 44 outwardly from the axis of the spindle. This does not interfere with proper key operation, but it precludes any known techniques for picking the lock, as is explained in detail hereinafter.

There is one additional feature provided with this lock that acts to prevent picking. As shown in FIGS. 20 and 21, one or more of the openings 41A for code pins 44 in the enlarged intermediate collar portion 41 are countersunk at 41B to provide a ledge 41C.

With this arrangement, one is precluded from making a key for the lock, even if he has the lock separate from its mounting. A way of obtaining a lock setting is to take the lock and place the spindle in a vise, which permits it to be torqued while an attempt is made to set the code pins at their breakaway point. With the provision of these countersunk portions, a slight movement of the spindle would result in the interlock pins 42 in bore 42A being moved over into the recess portion 418 (see FIG. 21) and thus providing a false sensing of the pins in the breakaway position. It is to be noted that when a lock is to be picked, the sensitivity of the feeler is important, and thus when a pin moves slightly, it is presumed to indicate that this is the breakaway position and -that a lock pin can be set to this depth. It can be appreciated that with the countersunk opening provided, one attempting to pick the lock would be lulled into a false sense of security. it is to be understood that there usually exists a slight clearance between the pins and their respective bores. The relationship between pins 42 and bores 42A and the canting position shown in FIG. 21 has been exaggerated for the purpose of illustrating the principle here discussed.

Before describing the key, it is to be noted that pins 51 are provided in the face of the barrel. The head of the pin 51 serves as a guide for the key cartridge 22 to be described in detail hereinafter. The pin heads in conjunction with the shoulder 335 form an annular chamber 33C. The key assembly 20 has a shoulder 23 that is notched at 23A, so that it may be admitted into chamber 33C and when turned, the shoulder will be retained in the chamber and thus prevent the key from being removed from the lock until the pins and notches coincide. By the use of a single notch, the key cannot be removed until the lock is re-locked. With a double pin and notch arrangement, the key can be removed in the unlocked position.

In a typical key for use with the described lock, the coded end of the key is in the form of cylindrical tubing, sized to fit the key entry passage 45, to be inserted axially into contact with the code pins 44. The coded end of the key is characterized by a set of code pin slots 47 that open endwise to receive each code pin endwise. The code pin slots 47 are separated and defined by leg portion 22L which are to fit into the spaces between adjacent code pins to provide for torquing of the spindle after all of the code pins 44 have been set to breakaway position.

The relationship of the coded end of the key cartridge to the code pins and the code pin travel depths to breakaway are best shown in the developed or unwrapped views of FIGS. 8 and 9 wherein the annular structures are shown unwrapped in accordance with the section line 8-8 appearing on FIG. 2. In these unwrapped views, the lock barrel 31, the fixed collar 35, the rotary holder 41, the key cartridge 22, and the key holder 21 are shown in proper axial or lengthwise relationship. It will be seen that the key cartridge 22 has slots 47 in its coded end of different depths to effect displacements of each code pin 44 a corresponding travel distance to achieve setting of the interlock pins 42 at breakaway position. In FIG. 8, the coded end of the key is in proper alignment with, but spaced from the code pins, 44, whereas in FIG. 9, the key end is fully seated in that each code slot has its head shoulder 22H in contact with the end of the corresponding code pin which has been displaced to align with the breakaway plane defined between the adjacent faces of the fixed collar 35 and the rotary holder 41. It is to be noted that the key legs 22L are spaced from the front face of the rotary holder 41 and that the key cartridge shoulder 23 is in contact with the outer surface 318 of flange 31F. Thus, it is the engagement of the key shoulder 23 with face 31B which determines depth of insertion, and the key legs are spaced from the rotary holder when the key is at the prescribed depth of insertion. Therefore, the required depth of insertion is indeterminate in the absence of the key shoulder 23.

One of the features of this invention resides in the fact that torque for rotating the lock shaft 345 of the spindle can be delivered only through the code pins 44 and the rotary holder 41. The pilot post portion 34F is free of any keyway or lug and is of smooth circular form. The front end, the only accessible region of the pilot post, is closely surrounded by the barrel flange 31F to preclude direct gripping and torquing of the pilot post. Moreover, in the preferred embodiment, the pilot post 34P is freely rotatable and when rotated blocks access to a number of the code pins to prevent them from being picked.

With a correct key, properly inserted, the normal lock opening sequences performed by the key is, first, to enter the key legs 22L in the interpin spaces and engage the slot shoulders 22H axially against each code pin, to depress the entire code pin array the prescribed distances to the breakaway plane and, second, to rotate the code pin and holder assembly by delivering torque through the key leg portions 22L to the new correctly set code pins. During this action, the key leg portions 22L tend to cant each pin only slightly away from the spindle axis, each leg portion acting in the wedgeshaped pocket between the corresponding code pin and spindle to develop the desired transmission of torque into the code pins and through the rotary collar to operate the lock shaft.

In the absence of a proper key, the lock cannot be opened by any known techniques for picking locks. There is no known device that can be used for opening this lock. The usual technique for opening a lock requires that the code pin travel depths be set by feeling their breakaway points in the presence of torque acting to rotate the lock spindle. All code pins must be set to their breakaway points before the lock is actually free to move and the precise code pin setting can only be known to its required accuracy after the lock has been rotated sufficiently that the end of the code pin is seated against a first region of the breakaway surface of the stationary collar 35. In the disclosed lock arrangement, there is no way to apply torque while also maintaining all of the code pins free to be depressed and gauged, as necessary, for feeling and holding the proper breakaway point for all pins.

The only way to apply torque to the spindle 34 is to employ a picking device having one or more pick legs insertable in the interpin spaces immediately adjacent the periphery of the pilot post portion 34P. The initial position of insertion for such a pick leg P is represented in FIG. 10. Thereupon, the picking mechanism would be actuated to swing the pick leg in a rotary direction, as illustrated in FIG. 11, so as to strike the code pin 44 and thereby tend to transmit torque for rotating the spindle.

Prior to pick of the spindle by means of the pick leg, it is not possible to know the correct setting for any pin. During torquing of the lock by means of the pick leg P, the code pins 44 which are contacted by the pin legs are deflected outwardly in the direction generally indicated by the dotted arrow A in FIG. 11. It should be noted that the pin leg P engages a region of the pin periphery which is oblique to the desired travel direction for the pick leg. Therefore, the pick leg tends to deflect the pin along the direction of the arrow A which is generally away from the surface of the pin which his contacted by the pick. While the rotary force delivered through the pick leg still tends to produce some torquing action in the desired direction, the major force component acts to cant the code pin while at the same time the pick leg P tends to bind in the generally wedgeshaped pocket defined between the curving periphery of each code pin 44 and the curving periphery of the pilot post 34F. Because of these relationships, the canting of the pin and the weding of the pick leg between the pin and the pilot post, the code pin is not free to be set axially during the time that a lock opening torque is acting. These relationships which prevent opening of the lock by known picking techniques result from the part relationships wherein the pins are located immediately adjacent the pilot post and are masked except for a minor region of the periphery thereof, which region is eccentrically displaced from the circular locus L defined by the centers of the code pins.

In addition, when the freely rotatable pilot post 34F is contacted, it will rotate about its axis, which is eccentric from the spindle portion 34D with the result that it will move to block access to code pins located opposite the area where a pin is attempted to be picked. Furthermore, during the picking of a given pin, it may be depressed past its break point with the result that the mechanical interlock between the elongated stern 42A and the cam plate 37 will occur, which will further prevent picking of the lock.

In FIG. 10A, there is illustrated a letter code pin 51 located in place between code pins 44. Only one is illustrated but, as described hereinafter, any number up to eight can be used. When these are in place, the space for a pick leg P is essentially eliminated, which makes picking all but impossible.

The lock coding combinations can be generated in any suitable pattern. For example, each pin position is established at any one of eight possible depth settings, as determined by the distance to breakaway of the corresponding code pin. The required travel for each code pin 44 is determined by the amount which the corresponding interlock pin 42 projects beyond the plane of its breakaway face. Each code pin projects beyond the front face of the rotary pin holder an amount greater than its required travel distance. As is explained in greater detail hereinafter, the extreme ends of the key legs 221. are arranged to stop short of the rotary holder 41 so that the key end does not bottom upon the rotary holder in a fashion which would directly reveal the required depth of insertion for a particular key.

For the embodiment of FIGS. 1 to 4, as illustrated and described herein, there are 8 code pins and there are 8 possible pin setting depths, there are at least 64 possible combinations of rotary position and depth of insertion for the proper key and only in one of these positions will the key be able to open the lock. Where the specific possible depth levels are not actually known, there is, in fact, a much greater number of possiblilities because depth is totally indeterminate.

To insert the key 20 into position in the lock, the notches 23A of the cartridge shoulder 23 are aligned with the pins 51 and the cartridge is moved into position against the surface 31B of flange 31F, which establishes that the key has been inserted to proper depth.

When the key is properly seated by engagement of the shoulder 23 against the face 318, all code pins are set to the breakaway plane and the key is rotated clockwise the distance determined by the limiting stop faces 37F presented by the cam washer 37 and the stop faces 32F presented by the arcuate lug 32L at the rear end of the lock barrel. The cam washer could be designed so that the limit of movement to the open position is 90 in which case the key could not be removed when the lock is opened, or it could be constructed so the lock opening would require 180, in which case the key could be removed after the lock is opened.

The improved axial tumbler-type lock, as already described and illustrated herein, may be embodied in other structural forms, some of which are illustrated in FIGS. 12 to 15. In FIG. 12, a stationary lock barrel 131 is shown with a stationary collar 135 equipped with interlock pins 142 and bias springs 143. A one-piece machined spindle structure 134 is journaled in these fixed parts and includes a lock shaft .1348, a rotary holder 141 and a stepped diameter pilot post portion 134P which includes a flanged front end 134F which projects towards the surrounding wall 1318 presented by the front end of the barrel 131 to define an annular key entry passage 145 leading into an annular mounting chamber 146. A set of code pins 144 are carried in the rotary holder 141 and project through the annular mounting chamber 146, with each code pin 144 being immediately adjacent the surrounding wall [318 of the barrel. Thus, the key entry passage 145 provides access only to eccentric peripheral regions of the code pins 144 and lock opening torque applied at such eccentric pin regions would result in inward canting and pin binding in a similar fashion to that already described.

In FIG. 13, an alternative arrangement is shown which includes a rotary holder 241 having an integral rearwardly projecting sleeve 234$ journaled in a stationary collar 235 and in turn mounting a center spindle 234. The stationary collar 235 is again equipped with interlock pins 242 and bias springs 243. In this form, the spindle 234 has a pilot post 234P terminating in an enlarged front end 234F projecting towards the surrounding wall structure 2418 presented by the cup shaped rotary holder to define a key entry passage 245 of limited transverse gap dimension. The code pins 244 are located in an annular chamber 246 defined be tween the spindle and the cup-shaped rotary holder 24], each code pin 244 being positioned immediately adjacent the surrounding wall 2418 presented by the rotary holder, so that only the eccentric code pin regions are accessible and so that inward canting and binding would result if a pick leg were inserted in the interpin spaces. The spindle 234, shown in FIG. 13, has its rear end fixed by means (not shown), so that a dead pilot post stmcture is provided. The lock shaft constituted by the integral sleeve section 2348 of the rotary holder carries and controls the latch. Once again, lock opening torque is transmitted through the code pins 244 to the rotary holder 241 and can be applied only after the code pins are set to breakaway position.

Another arrangement shown in FIG. 14 includes a stationary lock barrel 331 mounting a stationary collar 335 that is equipped with interlock pins 342 and bias springs 343. A rotary holder 341 having a generally cup-shaped forward end carries a set of code pins 344 and includes an integral rearwardly projecting sleeve portion 3348 serving as a lock shaft to receive a latch (not shown). A freely rotatable spindle 334 is journaled in the sleeve section 3348 and prevented from axial shifting by retainer screws 320 mounted in the sleeve section and projecting into a peripheral groove 3446 in the spindle. The spindle 334 is of stepped diameter configuration to present an enlarged pilot post structure 3341- at its front end which extends immediately alongside the array of code pins 344. The cup-shaped rotary holder 341 includes an inwardly directed front flange 341F projecting towards the pilot post structure to define the key entry passage 345 at a location aligned with the eccentric peripheral pin regions.

Still another embodiment is represented in FIG. 15 wherein a stationary lock barrel 431 mounts a stationary collar 435 equipped with interlock pins 442 and bias springs 443. A rotary holder 441 of tubular T- shaped transverse sectional configuration includes a sleeve section 4418 serving as a lock shaft and journaled in the stationary collar to carry a set of code pins 444. A spindle 434 is journaled in the rotary holder and is enlarged at its front end to provide a pilot post structure 434P extending immediately adjacent and alongside the code pin peripheries. The lock barrel 431 has a radially inwardly directed front flange 431F projecting towards the pilot post to define a key entry passage 445 registering with the eccentric pin periphery regions. The spindle 434, in this form, may either be fixed at its rear end in the fashion of FIG. 13, or may be freewheeling within the rotary holder in the fashion of FIG. 14.

The lock arrangements disclosed herein have a greatly expanded number of possible permutations and combinations, so that the total code combinations available reach astronomical figures. In addition to the code combinations available from 8 pin positions, each having 8 height levels, the lock arrangements accommodate a pattern of interference structures to be located in the interpin spaces which are accessible through the front entry passage 45. These interference structures may take the form of fixed posts 50, such as are shown mounted in the rotary holder 41 in the developed or unwrapped views of FIGS. 16 and 17, or may take the form of loose cylindrical pins 54, as shown in the unwrapped view of FIG. 16. The loose pins 54 may be deposited in the interpin spaces immediately prior to assembly of the spindle 34 and code pins 44 within a lock barrel, the pins thereafter being maintained captive by the restricted clearance conditions maintained by the flange of the barrel.

Where interference stmctures such as these are employed, the coded key end has additional slot regions 50S (FIGS. 16 and 17) and 548 (FIG. 18) affording clearance regions enabling insertion of the key end to the desired depth at the correct position. One of the important features of the invention resides in the fact that the interference structures may be sized to different heights and may be located at different interpin spaces and in various combinations of interpin spaces and heights. The interference structures or letter code pins particularly lend themselves to a vast multiplication of the possible code combinations, so that each code pattern of the basic 8-pin, 8-level code capacity is then individually expandable according to the combinations and permutations of the number of fixed posts and their locations and their particular heights. With the use of letter code pins, the number of possible code variations is in excess of one hundred million. Also, as previously mentioned, the interference structures, or letter code pins, guard the area between the peripheral regions of the movable code pins, prohibiting the use of a single picking tool.

The vast number of additional code combinations and the particular nature of the interference structures also lend themselves to master keying systems based upon the particular lock and key system illustrated herein.

In a typical lock construction of the type shown in FIGS. 1 to 4, this type being compatible with existing lock mountings, the LD. of the lock barrel flange 31F typically is about 0.385 inches and the OD. of the pilot post portion 34] of the spindle is typically 0.325 inches, so that the front entry passage 45 has a transverse gap of (0.385 0.325 i 0.030 Inches In the current types of prior art locks, a transverse gap dimension of about 0.050 inches for the front entry passage is commonly employed, but this affords excessive clearance for access to the pin mounting chamber.

In accordance with one embodiment of the present invention, the code pins 44 are of 0.078 inches diameter positioned on a bolt circle diameter of 0.406 inches to extend immediately alongside the pilot post portion. The pin radius is 0.039 inches, which is larger than the transverse gap dimension of 0.030 inches to insure that access through the front entry passage 45 is limited to a minor peripheral region of the code pin. With the stated dimensions, the transverse gap should be 0.040 inches or less to insure that pick structures will engage effectively only with eccentric regions of the code pins. The letter code pins for use in the interpin spaces are also 0.078 inches diameter and are on the same bolt circle as the code pins and they are immediately adjacent thereto, which further limits the access to the code pins.

In view of the importance of the feature that the present lock arrangement is difficult to pick, the invention contemplates the use of hardened steel for the spindle 34, the code pins 44 and the lock barrel 3], so that these parts resist deliberate destruction and, more importantly, resist gouging by conventional tools, which may be used for breaking open a lock. V

In connection with one aspect of master keying, the invention also contemplates the use of 3-pin tumbler assemblies at certain of the code pin positions. Identical lock arrangements are shown in FIGS. 16 and 17, wherein, for certain of the tumbler assemblies, in addition to the interlock pin 42 and code pin 44, there is provided a stub pin insert 52 of a length selected in accordance with the distance between two given pin depth levels. The use of an insert pin in a given tumbler assembly provides that assembly with two different travel depths to breakaway, one travel depth corresponding to registry of the lower end of the insert pin 52 in the breakaway plane and the other corresponding to registry of the upper end of the insert pin 52 in the breakaway plane. In these instances, two different code keys can open the same lock, as is shown in FIGS. 16 and 17, the difference between the keys being the depths of the particular code slots 52S and 1528 (see FIG. 16) and 53S and 1535 (see FIG. I7), which are associated with the tumbler assemblies that include the insert stub pins 52. As can be seen from a comparison of the set of corresponding slots 52S and 538, the difference in the slot lengths is equal to the length of the stub pin 52. The same is found from a comparison of the slots 1528 and 1535.

To illustrate the nature of the master keying systems, which are utilized in accordance with the practice of the present invention, a display panel is represented in FIG. 19 with a plurality of locks arranged in horizontal rows labeled 80A to 80F. Each lock in the top row 80A has a code pattern, as illustrated in FIG. 19A, wherein reference characters A to H are applied to the code pins, each to represent the travel distance to breakaway for that pin. Wherever these same letters A to H appear in FIGS. 19B to 19F, it will be understood that the corresponding code pins have the same travel distance to breakaway. Each lock in the second row 80B has a code pattern, as represented in FIG. [93, wherein all code pin positions and travel distances are identical with the corresponding pins of the locks of the first row.

The only difference between the locks of the first and second rows is that each lock in the second row has a letter code pin-type of interference structure 508 at the interpin space between pins A and B. Correspondingly, each lock in the third row 80C, as shown in FIG. 19C, has the same code pin arrangement, but has the letter code pin-type of interference structure 50C at the interpin space defined between pins B and C and each lock in the fourth row 80D, as represented in FIG. 19D, has the same code pattern and has a letter code pintype of interference structure 50D between code pin positions C and D.

It should be apparent that any key which will open one of the locks shown in FIGS. 198 to 19D will also open the locks of the type shown in FIG. 19A. Conversely, it is possible to arrange a key suitable for opening the locks shown in FIGS. 19A and 198, so that it will not open either of the locks shown in FIGS. 19C and 19D. Such a key would be a master key only for the locks shown in FIGS. 19A and 198. Another key suitably modified to include additional slotting to accommodate each of the

interference structures

50B and 50C serves as a master for each of the locks shown in FIGS. 19A, 19B, and 19C. Still another key that includes additional slotting for each of the

interference structures

50B, 50C and 50D can be a master for each of the locks shown in FIGS. 19A to 19D.

The locks in the fifth row 80E are of the type shown in FIG. 19E, wherein letter code pins 503 and 50C are provided both in the space between code pin A and B and in the space between code pins B and C. The key for opening the lock shown in FIG. 19E would also be a master for the locks shown in FIGS. 19A to 19C. Correspondingly, the master key for opening the locks shown in FIGS. 19A to 19D would also be a master key as to the lock shown in FIG. 19E.

The type of master keying relationships described for the locks illustrated in FIGS. 19A to 19E enable various levels in the supervision and control of security. For example, a route man may be assigned to a route, all of the locks of which are of the type shown in FIG. 19B. Another may be assigned to a route where all of the locks are of the type shown in FIG. 19C. A supervisor may be provided with a key for opening the lock shown in FIG. 19E, this key will also be a master for the locks of FIGS. 19B and 19C.

In the sixth row of the display panel, the locks are of the type shown in FIG. 19F, wherein all code pin positions are seen to have been uniformly rotated 45. Additional series of locks may be provided wherein the code pins are uniformly rotated additional amounts. Thus, with a composite key as described herein the key for opening the lock shown in FIG. 19A will not open the lock shown in FIG. 19F unless the proper point of entry is discovered and the depth of insertion is maintained the same.

Various combinations of the described master coding using rotated codes, using interference structures of various heights and at various positions, and using various depths of insertion can be developed to provide high capacity and complex code systems.

Referring now to FIGS. 22-26, there is illustrated another embodiment of the invention. Essentially, the lock disclosed in this embodiment is similar in many respects to the embodiments discussed above and where identical parts are present they are given the same numbers they have in FIGS. 1-3. For example, the embodiment under discussion contains among other novel aspects l the novel feature of providing a limited space between the center post and surrounding housing .to prevent unauthorized picking of the lock and (2) no indicia that would permit one attempting to pick the lock to determine the depth of setting of the key to be employed and a number of other features which have been discussed in detail above and which will be apparent when one compares FIGS. 22-26 with other figures in the drawings disclosing other embodiments.

This particular embodiment is additionally unique in that it includes an arrangement whereby the setting or combination of the lock can be changed without having to remove or replace any of the parts thereof.

Essentially, various structures are provided which permit changing of the lock setting which includes (I retaining the code pins in their preset position, and providing one or more abutments or barries that are positioned or rotated relative to the code pins, (2) moving a first group of code pins in a first holder relative to code pins contained in an adjacent holder or (3) moving the barriers and first group of code pins together relative to an adjacent holder and associated code pins. In each of these situations a new key will be required to open the lock and the original one will no longer be effective.

Briefly, in the first arrangement, a freely rotatable sleeve member is provided between the head of the center post and an adjacent pin holder which sleeve contains one or more barriers that can be placed in preselected positions relative to various code pins in a holder. Such an arrangement, of course, requires a key that would fit over such barriers in order to open the lock. It can be appreciated that if the barriers are movable when the pins are in a depressed position, the lock setting can be changed at will. The permissible changes that can be made will, of course, vary depending on the number of barriers employed. In this case, the setting of the code pins has not been changed. In the second situation where the barriers are not present the pin setting can be changed by moving the pins in a first holder assembly relative to an adjacent holder assembly which repositions the pins of assorted lengths in the first holder to different positions relative to a set of adjacent code pins which changes the combination" of the lock. The third possible pin setting change can be effected by moving the barriers and first group of code pins together relative to the adjacent set of code pins.

In addition to the aforementioned novel means of permitting changing of the lock setting, the lock is so designed whereby the combination can be changed by a key that would not be capable of opening the lock.

All that is necessary is that in the situation where the barriers only are moved the key be capable of depressing the pins in the first holder below the plane permitting the barriers to be moved to different positions rela tive to the code pins.

In the second situation where the barriers are not provided and only the code pins in the first holder are moved, the key must be designed to move the code pins in the first holder to a position permitting movement of the first holder relative to adjacent holder. In the third situation, where the barriers and first holder are to be moved, the key is designed to engage the barriers and move the pins to a breaking point between the first pin holder and the intermediate pin holder. This will permit rotation of the sleeve and associated barrier or barriers to different positions, thus requiring that a still different key be employed to open the lock. In each of these situations, the key for changing the *combination" will be suitably notched to permit its removal from the lock barrel after the setting has been changed.

The details of the novel structure employed in this embodiment can best be seen by referring to the figures, specifically, wherein FIG. 22 shows an exploded perspective view of the lock shown with a key 521 adapted to be inserted into the lock barrel 531. The center post or spindle 534 is shown extending through the rotatable pin holder 550, the end 551 of which is designed to fit into center opening 552 of intermediate pin holder 554.

As described in detail with respect to another embodiment the center spindle is freely rotatable, which prevents it from being used as a reference by one attempting to pick the lock.

The stationary collar 535 containing interlock pins 542 is shown removed from the stem portion 556 of pin holder 554. It is to be noted that there are code pins 558 extending through openings in pin holder 550, which pins are adapted to engage with code pins 560 of pin holder 554.

One way to provide for a change in the lock setting and thus the key required to open the lock is to locate between center post 534 and pin holder 550 a freely rotatable sleeve 562 which contains notches in which abutments or barriers, as, for example, 564, are provided. When the pins 558 are depressed by a key to where they are located totally within the holder 550, the sleeve 562 along with abutments 564 can be rotated, which would then place the abutments 564 in different positions relative to the pins 558 and thus change the setting of the lock, requiring a different key.

To show how the setting of the lock can be changed by moving the barriers and the code pins 558 to a new position, reference is made to FIG. 24, which is a crosssectional view of the lock taken along line 24-24 of FIG. 23, in which the various components thereof are shown in their assembled position. In this embodiment, the

pins

542, 558, 560 are biased by spring 543 against a ring 536 that is held in position relative to holder 550 by a ring 538. The ring is free to move between the ring 538 and the barrel flange 531F will take the position shown in FIG. 23 when the key 521 is inserted. The outer surfaces of the ring 536 are curved, so that any attempt at breaking the lock will act to cant the ring and thus further reduce the size of gap 545 availabe for picking. The key 521 is shown partially inserted in the gap 545 formed between post 534 and surrounding wall 533W, and the locking pins in the various holders are not at their breaking point, which thus prohibits either resetting of the lock, or opening of the lock. When it is desired to change the combination of the lock by changing the position of the code pins 558 of different lengths relative to the code pins 560 along with the location of the barriers, a key 521 is inserted, which has a slot fitting over the barriers 564 and depresses the

pins

558 and 560 to a position where the holder 550, sleeve 562, and associated barriers 564 can be moved relative to the holder 554. When this relative movement is permitted, the code change can be made and all that is necessary is that the shoulder 523 of key 521 be suitably notched to permit removal of the key after the prescribed rotational movement. Thus, after the barriers and/or code pins have been rotated to a new position and the key removed, it will be obvious that the same key that originally fit the lock would no longer work and a new key would be required.

It remains to note that the opening and closing of the lock shown in FIGS. 22-26 takes place in the same general manner as that discussed with respect to the other embodiments in that when the pins 560 and interlock pins 542 are positioned to permit rotation of holder 554 relative to stationary collar 535, the lock can be opened.

Thus, while preferred constructional features of the invention are embodied in the structure illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit and scope of the appended claims. For example, the barrel could be designed so the key seats against the outer surface, or the stems 42A instead of being made to contact a cam stop plate could contact a switch, causing an alarm to ring. Also,

the pins 51 could be eliminated and some other indicia employed for determining the key entry position. in this situation, the key could be removed in any position.

It is, of course, intended to cover by the appended claims all such embodiments that fall under the terms thereof.

What is claimed is:

1. ln an axial tumbler lock having a barrel housing, a rotary holder assembly carrying at least one set of lengthwise shiftably mounted forwardly projecting code pins spaced about and parallel to an axis of rotation for the holder, a lock shaft drivingly engaged for operation by rotation of the rotary holder assembly, means normally blocking the rotary holder against rotation and responsive upon predetermined lengthwise shifting of the code pins to release the rotary holder assembly, means forwardly of the holder assembly including a center post in engagement with said holder assembly and freely rotatable relative thereto defining a lengthwise narrow annular key entry opening with said barrel housing, a sleeve surrounding said center post and located between the center post and rotary holder assembly including at least one barrier member positioned between outwardly extending adjacent pins in said rotary holder assembly whereby the setting of the lock can be changed by depressing said last mentioned pins and moving the barrier to different locations relative thereto.

2. An axial tumbler lock in accordance with claim 1 in which the rotary holder assembly consists of a first holder and associated pins connected to said lock shaft and a second holder containing code pins juxtaposed relative to said first holder with the code pins in the two holders in alignment, a barrier being disposed between at least one pair of adjacent code pins in said second holder, whereby the setting of the lock can be changed by engaging and depressing the pins in the first holder to a plane where the second holder can be rotated rela tive the first holder to change the setting of the lock.

3. In an axial tumbler lock and key combination, a lock having a barrel, a rotary holder defining a first surface adjacent the front of the lock carrying a symmetrical array of lengthwise shiftably mounted forwardly projecting code pins spaced about and parallel to an axis of rotation for the holder, said barrel having a reference surface spaced from the ends of said code pins, the lock having a narrow annular key entry passage that is in registry with the array of code pins being individually settable lengthwise in the holder to release the holder for rotation, a key cartridge having a shoulder and a coded end insertable lengthwise through said entry passage to engage and set said pins to release the holder for rotation through the code pins only when said cartridge is properly disposed in said key entry passage and is advanced to a predetermined depth of insertion determined by the contacting of the shoulder with said reference surface, and said coded end of said key cartridge is spaced from the first surface of said holder when said pins are released for rotation.

Claims

1. In an axial tumbler lock having a barrel housing, a rotary holder assembly carrying at least one set of lengthwise shiftably mounted forwardly projecting code pins spaced about and parallel to an axis of rotation for the holder, a lock shaft drivingly engaged for operation by rotation of the rotary holder assembly, means normally blocking the rotary holder against rotation and responsive upon predetermined lengthwise shifting of the code pins to release the rotary holder assembly, means forwardly of the holder assembly including a center post in engagement with said holder assembly and freely rotatable relative thereto defining a lengthwise narrow annular key entry opening with said barrel housing, a sleeve surrounding said center post and located between the center post and rotary holder assembly including at least one barrier member positioned between outwardly exTending adjacent pins in said rotary holder assembly whereby the setting of the lock can be changed by depressing said last mentioned pins and moving the barrier to different locations relative thereto.

2. An axial tumbler lock in accordance with claim 1 in which the rotary holder assembly consists of a first holder and associated pins connected to said lock shaft and a second holder containing code pins juxtaposed relative to said first holder with the code pins in the two holders in alignment, a barrier being disposed between at least one pair of adjacent code pins in said second holder, whereby the setting of the lock can be changed by engaging and depressing the pins in the first holder to a plane where the second holder can be rotated relative the first holder to change the setting of the lock.