US3462983A

US3462983A - Pin tumbler lock assembly

Info

Publication number: US3462983A
Application number: US593015A
Authority: US
Inventors: Michael A Evanish
Original assignee: MICHAEL A EVANISH
Current assignee: MICHAEL A EVANISH
Priority date: 1966-11-09
Filing date: 1966-11-09
Publication date: 1969-08-26
Anticipated expiration: 1986-08-26

Description

Aug. 26, 1969 M. A. EVANISH PIN TUMBLER LOCK ASSEMBLY 4 Sheets-Sheet l D INVENTOR. M/chae/ A. E vanish W W HIS A TORNEYS Filed NOV. 9, 1966 Aug. 26, 1969 M. A. mmsH 3 462,983

. PIN 'I'UMBLER LOCK ASSEMBLY Filed Nov. 9, 1966 4 Sheets-Sheet 2 I2. I e cbo e c F a Micha /zYi zzm-sh HIS ATTORNEYS 26, 1969 M. A. EVANISH 3,462,983

PIN TUMBIJER LOCK ASSEMBLY INVENTOR.

Michael A. E vanish 7 M a 72 H/S TTUR/VEYS Aug. 26, 1969 Filed Nov. 9, 1966 M. A. EVANISH PIN TUMBLER LOCK ASSEMBLY 4 Sheets-Sheet 4 INVENTOR.

fiMichae/ Awh BY WM, WC

H/S ATTORNEYS United States Patent 3,462,983 PIN TUMBLER LOCK ASSEMBLY Michael A. Evauish, 3561 E. Court, Pittsburgh, Pa. 15205 Filed Nov. 9, 1966, Ser. No. 593,015 Int. Cl. E05b 25/00, 35/08, 27/00 US. Cl. 70-383 11 Claims ABSTRACT OF THE DISCLOSURE A key-operated tumbler element locking mechanism has been devised to selectively utilize a plurality of operating keys, including a master key. The mechanism is constructed to be released for resetting to use a second operating key by a reset control key which moves the lock from a locking position to a resetting position and back to the locking position. Thereafter, a first operating key for which the lock has been set is inserted and is employed to turn the mechanism from its locking position to and past its unlocking position to a second or final resetting position. At the latter position, the second operating key is introduced and thereafter utilized for moving the mechanism between normal unlocking and locking positions.

This invention relates generally to key-operated pin tumbler locks and more specifically pertains to locks which are adaptively constructed to permit the utilization of more than one key for the operation thereof.

Setting my lock assembly for operation by a specific operating key has the effect of limiting the locks operation to such key and preventing the use of other operating keys. Repeated resetting of the lock assembly for operation by successive operating keys does not, however, interfere with the locks operation by its master key.

The resetting of my lock assembly can only be accomplished by the locks owner, since just prior to resetting, the lock assembly must be first internally released or primed by means of a special control or release key in the possession of the owner.

It is believed that my lock assembly and its associated selection of keys which constitute my invention will be found extremely useful and advantageous when installed as a lock system in a commercial building such as a hotel or apartment house, etc. As in a conventional system, my lock assembly, when installed on a hotel room door, will be capable of operation by an operating or primary key in the possession of the room patron. The cleaning staff or management will also be able to gain access to the room by means of a master key. The master key will also operate all associated lock assemblies in the system on the other various doors throughout the building, with each lock assembly in the system being operable by a separate and different operating key held by the patron of a specific room. It will be possible to change over all or some of the lock assemblies in the system to adapt them to be operable respectively by new and different operating keys. Such change over will render the lock assemblies inoperable by the operating keys utilized prior to the change over operation, although subsequent change over could re-establish sole operability by previously employed operating keys. Such key changeover will not effect the operability of the systems master key with respect to operation of the various lock assemblies in the system.

In addition, a previous tenant can be prevented from gaining reentry to a room by use of an operating key retained in his possession. The tumbler arrangement or setting within a given lock assembly can be easily altered 3,462,983- Patented Aug. 26, 1969 by proper key manipulation on the part of management at any time to accomplish key changeover. The changeover will not effect the ability of service help to enter the room at any time with the master key, and the changeover can be successively repeated as required to permit operation by any operating key in the total number of primary keys to which the lock assembly is designed to be successively adaptable.

The extreme adaptability of my lock assembly would enable a system made up of a large plurality of such assemblies to be separable into submaster groups wherein, for example, all lock assemblies in each group could be selectively made operable by a specific distinctive operating key, and with all lock assemblies in the entire system being operable by a single master key. Such subgrouping could be utilized to have all lock assemblies on a single floor of a building operable by the same operating key. Regrouping of locks to other selected grouping arrangements could be accomplished freely as desired.

Another distinctive advantage in my invention is its adaptability for use with public lockers commonly found in public transportation depots. From the foregoing remarks it is apparent that the owner of a public locker concession having a plurality of lock mechanisms, in accordance with my invention, on the doors of his lockers, would be able to selectively reset any of the locks to be no longer operable by a first key and, instead, be operable by a second key. Thus, an unreturned key would not necessitate a change of locks to provide security for a subsequent locker patron.

BACKGROUND OF THE INVENTION Heretofore, the standard key-operated pin tumbler lock has been improved by the introduction of various new structural combinations. Many of these improvements in the art have been directed to the objective of providing a pin tumbler lock operable by the insertion of more than one key. Such locks are commonly employed in commercial buildings where it is desirable to have a plurality of locks constituting a lock system with each lock operable by a respectively different operating key but all operable by a single master key.

Other improvements in the art have been directed to the objective of providing a lock that is susceptible to permanent internal rearrangement. This type of pin tumbler lock, often referred to as a construction lock, may be utilized for a period of time during which it is operable by a first key in the possession of a contractor. Insertion and rotation of a second key by the owner after the construction job is completed will cause a tumbler to be permanently ejected or a fragile tumbler to be parted at an intermediate break line so that henceforth the lock will only be operable by means of the second key.

This single changeover type of lock lacks the versatility that is inherent in my invention. Also, in such locks of the prior art, auxiliary apparatus is often provided that is entirely useless after the permanent changeover to the second key has been made. It is also not unusual for such a lock to be inadvertently changed over prior to the desired time, thus, defeating the locks purpose.

Another pin tumbler lock of the prior art, though adaptable to repeated key changeover, has the disadvantage of requiring complete disassembly for rearrangement of the pin tumbler combination therein in accordance with a new and different operating key. The task of disassembling a locking device and accomplishing a tumbler rearrangement requires the knowledge of a skilled locksmith, considerable expenditure of time, and is, accordingly, prohibitively expensive. The need for improving the means of changing such locks has been recognized in the prior art by the introduction of an improved lock constructed to permit the removal of the key plug or cylinder without complete disassembly of the device from its mounted position. In such improved locks, a special control key is provided that serves the purpose of unlocking or releasing the key plug from its housing. Notwithstanding the considerable contribution to the art, such locks only simplify disassembly rather than eliminate the need for it. Therefore, a skilled person familiar with lock construction is still required to service and reset the lock, and the risk of losing parts during the disassembly and reassembly operation remains.

It has therefore been a primary objective of my invention to provide a rekeying system whereby the setting or internal structural arrangement of a lock may be changed without disassembly of the lock to effect an operating key change over with the changeover being such as to involve no permanent or irreversible change in the locks structural arrangement.

A further object of my invention has been to provide a. key-operated pin tumbler lock assembly wherein the operative pin tumbler combination thereof may be temporarily changed or rearranged without disassembly an infinite number of times by selectively adapting the assembly for sole operation by any one of a plurality of different operating or service keys.

A still further object of the invention has been to devise an improved pin tumbler lock which is substantially foolproof from the standpoint of the use of various operating keys, a master key and a resetting or control key.

DESCRIPTION OF THE INVENTION The details of construction, operation, and other advantages of my operation will be best understood from the ensuing description wherein the structural form of a preferred embodiment of my lock assembly is emphasized for the purpose of illustration and without intended limitation thereto.

In the accompanying drawings, wherein like reference characters denote like parts:

FIGURE 1 is a pictorial or perspective view of a preferred embodiment of my lock assembly;

FIGURE 2 is an elevational view in vertical section of two associated internal elements of the lock assembly shown first in FIGURE 1, here shown in enlarged scale as compared to FIGURE 1;

FIGURE 3 is a front elevational view of my lock assembly, shown on the same scale as FIGURE 1;

FIGURE 3A is an exploded perspective view of my lock assembly, illustrating the major elements of the preferred embodiment of my invention;

FIGURES 4, 6 and 8 are respective side elevational views of an upper portion of my lock assembly, each taken from the left side of the assembly as shown in FIGURE 3 but on an enlarged scale as compared to FIGURE 3, and each having a portion of the housing cut away in vertical section to illustrate respectively different tumbler element arrangements in accordance with the operation of my lock assembly;

FIGURES 5, 7, 9, and 10 are respective top plan views of my lock assembly on the same scale as FIGURES 4, 6, and 8, with each view showing a portion of the housing cut away in horizontal section to further illustrate internal arrangements of the tumbler elements in accordance with the operation of my lock assembly;

FIGURE 11 is a side elevational view of my assembly, taken from the left side of FIGURE 3 but in enlarged scale as compared thereto, and shows elements of the lock assembly relating primarily to the reset or key changeover operation of the assembly;

FIGURE 12 is a rear or back end elevational view of my lock assembly, showing various elements associated with the reset or key changeover mechanism of the assembly;

FIGURE 13 is a rear or back-end elevational view similar to FIGURE 12 except showing certain elements repositioned in accordance with the operation of my lock assembly;

FIGURE 13A is a substantially enlarged view of certain operatively-associated elements first shown in FIG- URES12 and 13;

FIGURE 14 is a side elevational view of my lock assembly in vertical section showing the interaction of the assembly elements associated with the use of a master y;

FIGURE 15 is a side elevational view of my lock assembly in vertical section showing the interaction of the assembly elements associated with the use of a control or release key that is utilized to prepare the assembly for the key changeover operation;

FIGURES 16, 17, and 18 are respective fragmentary views in vertical section as viewed from the front of the lock assembly, each illustrating relative positioning of tumbler elements during the operation of the assembly; and

FIGURE 19 is a front elevational view of my lock assembly similar to but on a slightly smaller scale than FIGURE 3, and illustrating the degree and direction of rotation of the assembly key plug or cylinder during a step in the key changeover operation thereof.

(A) Elements of the lock assembly In FIGURES 1, 3 and 3A there is shown a pin tumbler lock assembly 8 comprising a body of lock housing 10 having the geometric form or general configuration or a rectangular solid. The housing 10, as shown in FIGURE 3, is provided with a longitudinal axial opening or cylindrical bore 11 leading from the front to the rear surface thereof. The housing 10 contains four longitudinally extending rows (12, 12', 13 and 13') of radially-inwardly extending pin tumbler holes. Each of the four rows has five holes arranged in a spaced-apart relationship longitudinally through the housing 10 and leading from an outer surface of the housing inwardly to the central bore 11. In the various figures of the drawing, each of the

rows

12, 12', 13 and 13 in the housing 10 is shown as having five parallel spaced-apart holes designated respectively, as viewed from the front of the housing toward the back, as a, b, c, d, and e. Hence, hereinafter, the holes in any one row may be referred to by combined row and hole reference characters such as hole 12a, 12b, etc.

Each of the five spaced-apart holes in row 12 extends radially-inwardly toward the axis of the bore 11 from the top surface of the housing 10 along the housings central vertical axis. Each of the holes in the row 12 extends radially-inwardly from the bottom surface of the housing 10 and toward the axis of the bore 11, in an opposed relation to holes of the row 12. The holes of row 12 are in respective vertical alignment with holes having like reference character designations in the row 12 thereabove.

Two oppositely positioned side rows 13 and 13' have five holes each extending radially from opposite side sur-- faces of the housing 10 along its central horizontal axis. The number of holes in either of

rows

13 and 13 are equal to the number in either of the rows 12 and 12'. The holes making up the row 13 are in horizontal alignment with the respective holes designated by like reference characters of the row 13'. Thus, the housing 10 has four rows of five holes each, with the rows disposed in a quadrant relationship, and the respective holes in each row in circumferential alignment through the housing with holes of like reference character designation in the other rows of the housing 10.

With particular reference to FIGURES 3A and 11, it will be noted that the housing 10 is provided, adjacent and parallel to its back surface, with opposed pin tumbler holes 50 and 50 opening respectively inward from the top and bottom surfaces of the housing 10 to the bore 11. Although the

holes

50 and 50 are in longitudinal spaced-apart alignment with the holes of rows 12 and 12', respectively, holes 50 and 50' are not referred to herein as constituent holes of the

rows

12 and 12 because they do not cooperate with the

row

12 or 12 in the normal locking or unlocking operation of the lock assembly 8 mechanism. The holes 50 and 50' constitute a part of a key plug engaging means that will be separately explained.

As shown in FIGURES 1 and 2, a rotatable key plug or lock cylinder 14 is mounted in the bore 11 of the housing 10. The key plug 14, as shown in FIGURE 2, is provided with a front end annular flange 15 which extends radially-outwardly therefrom and fits into a correspondingly shaped groove or recess 11a provided in the housing 10 and circumjacent the lip of the bore 11. A longitudinally extending rectangularly-shaped keyway slot 17 is provided through the key plug 14 to receive the blade of a key inserted therein.

Longitudinal ridge portions

18 and 19 extend inwardly into the keyway slot 17 to engage correspondingly shaped grooves in a key blade. As shown in FIGURE 1, the ridge portion 19 has a wider vertical expanse than ridge portion 18 to assure that a key blade adapted for insertion therein cannot be inadvertently reversed and inserted in an upside-down manner.

As shown in FIGURE 2, the key plug 14 is provided with oppositely-disposed

rows

29 and 20" of longitudinally spaced-apart tumbler holes opening from the keyway slot 17 and extending outwardly from the outer surface of the key plug 14. Each of the rows 20 and 20' is comprised of five holes designated as a, b, c, d, and e, respectively. As in conventional construction of a lock cylinder or key plug, the width of transverse distance across the keyway slot 17 is less than the diameter of one of the pin tumbler holes opening therefrom and thus the inner end of each hole comprises opposed depressions in the side wall of the keyway slot 14- in order that a pin tumbler positioned within the hole and resting against either the

ridge

18 or 19 will be maintained, by means of the side wall depressions, in axial alignment with its hole. It should be noted with reference to the drawings that in figures other than FIG- URE 2, such as FIGURE 3, each pin tumbler hole through the key plug 14 is shown as having a diameter approximately the same as the width of the keyway slot 17, since the inclusion of larger diameter pin tumbler holes is not considered critical and will be understood without specific illustration by a person skilled in the art.

The

rows

20 and 20 of holes in the key plug 14 are adapted to form elongated or extended bores through which pin tumblers can be slidably moved, with such bores formed by rotation of the key plug 14 so that the holes of the

rows

20 and 20 are moved into aligned communication with the holes in the housing 10. In accordance with the operation of the lock assembly 8, holes of row 20 of the key plug will be moved into aligned communication with holes of either row 12 or row 13 of the housing 10, with such movement correspondingly causing holes of row 20' of the key plug 14 move into aligned communication respectively with holes of rows 12' or 13 of the housing 10.

The key plug 14 has a back end portion 16 of a smaller diameter than the main body of the key plug 14. The back end portion 16 is adapted to mountably receive a sleeve-like element or position-retaining ring 26 thereon. The back end portion 16 is provided with a tumbler hole that extends vertically upwardly from the keyway slot 17 and a pin tumbler hole 25' that extends vertically downwardly from the keyway slot 17 and in vertically alignment to the pin tumbler hole 25.

It will be seen in FIGURE 2 that the ring 26 that is carried on the back end portion 16 (as shown in FIG- URE 11) is provided with an upwardly-outwardly extending pin tumbler hole 28 that is adapted to establish an elongated pin tumbler bore in cooperation with the hole 25 of the key plug 14 and the hole 50 of the housing 10. A pin tumbler hole 28 extends vertically downwardly through the side wall of the ring 26 and is adapted to establish an elongated pin tumbler bore in cooperation with the hole 25 of the key plug 14 and the hole 50' of the housing 10. The ring 26 is further provided with an upwardly-outwardly extended lug 27 which acts, as does the ring 26, as part of a reset or release means in accordance with this invention, as will be described in detail further on in this specification.

As shown in FIGURES 3A, 12, and 13, the housing 10 is provided with a square planar plate 22 that may be attached by means of screws 23 to the back end of the housing 10 to form the back surface thereof. The plate 22 is provided with a central substantially circular opening 22a having a diameter slightly larger than the outside diameter of the back end portion 16 of the key plug 14 so as to permit the back end portion 16 to extend outwardly therethrough. The fiat end surface of the back end portion 16 ends flush with the outer surface of the plate 22, and a substantially circular planar end plate 21 is attached to the end surface of the back end portion 16 by means of screws 24. The dimension across the key plug end plate 21 is such that a portion thereof extends over the outer surface of the plate 22 and thus serves to movably retain the key plug 14 in its mounted position within the housing 10.

FIGURES l2 and 13 also show that a slot-like opening 22b is provided at the upper periphery of the opening 22a in the plate 22. The opening 22b permits the lug 27 of the sleeve-like ring 26 to extend outwardly therethrough. The width of the opening 22b is such that the lug 27 is permitted to move back and forth therein in a limited lateral direction during one operational phase in the use of the lock assembly 8.

The key plug end plate 21 has approximately a quarter of its curved circumferential edge recessed or notched inwardly to provide two straight radially disposed striking surfaces, ledges or

edges

21a and 21b. A portion of the outer edge of the key plug end plate 21 adjacent the striking edge 21b follows a tangential line to form a substantially straight edge portion 21c that merges with the outer end of the striking surface edge portion 21b to form a slightly laterally-outwardly extending point 21d.

A substantially small eccentrically mounted pate 43 is located directly above the opening 22b of the plate 22. The plate 43 is adapted to pivot on a fixed pin 43a and has a spring means 44 that urges it to turn clockwise as viewed in FIGURE 12. The plate 43 is provided with two substantially oppositely disposed finger-like portions 43b and 430 that extend respectively laterally-outwardly therefrom.

To the left of the opening 22b, is mounted a pawl 45 which is shown in an enlarged view in FIGURE 13A. The pawl 45 is movably fastened to the plate 22 by a fixed pin 45a and has a spring means 46 connected to the lower end thereof to urge the upper end of the pawl to the right and downward as viewed in FIGURE 12.

The pawl 45 is shaped to have a downwardly facing edge or striking surface 45b which, in the operation of the lock assembly, will engage the finger-like portion 43b of the eccentric plate 43. Mounted substantially over and contiguous to the surface of the pawl 45 is a small pivot rod 47 that also is pivotally attached by means of the fixed pin 45a. The rod 47 has an upper end 47b that is attached to a spring means 49 that tends to pull the upper end 47b in a downwardly direction so that a lower end 47a tends to swing in an upwardly counterclockwise direction. A fixed pin 48 extends outwardly from the surface of the pawl 45 and is in a position to contact the edge of the rod 47 and prevent the end 47a from swinging upwardly therepast.

Four respectively different keys are shown in the drawings: a first operating or service key designated as key 40 as depicted in FIGURES 8 and 9, a second operating or service key designated as key *41 as shown in FIGURE 10, a master key 42 as shown in FIGURE 14, and a special control or release key 51 as shown in FIGURE 15.

The two

operating keys

40 and 41 are representative of a plurality of operating keys by which the lock assembly 8 may be successively and independently operated. The number of such keys which can be adapted to operate the lock assembly 8 is only limited by the number of different pin tumbler combinations possible in any given construction of the invention. In other words, equally increasing the number of holes in each longitudinally spaced row in the housing 10 and correspondingly increasing the number of holes in the key plug 14 to function in cooperation therewith and form additional tumbler bores will proportionately multiply the number of available combinations and thus the number of primary or operating keys that can be adapted to operate the lock assembly 8.

As shown in FIGURES 8 and 9, the service key 40 comprises a head portion 40a by which the key is gripped for insertion and turning, a blade portion 40b for insertion into the keyway slot 17, a longitudinal side groove 40c that will engage and ride inwardly on the ridge 18 (as shown in FIGURE 1), and a bitted or cut edge portion 40d that is designed to contact a series or combination of pin tumblers or movable elements in the lock mechanism. A wider groove portion (not shown) similar to groove 40c will also be provided on the opposite side of the blade 40b to engage on and ride inwardly upon the ridge 19.

As shown in FIGURE 10, the second service key 41 comprises much the same features as the first key 40 but differs essentially in that the blade edge thereof is cut or bitted differently whereby each key will engage a different combination of tumblers Within the keyway slot 17 of the key plug 14.

The master key 42, shown in FIGURE 14, comprises a head 42a with a blade 42b having a longitudinal groove 42c on one side and a longitudinal groove on its other side, the same as key 40, that will serve the same purpose as the grooves of the service key 40. The master key head 42a is provided with a substantially wider neck portion 42d as compared to the respective neck portions 40c and 41s of the

service keys

40 and 41. The purpose for the wider neck portion 42c will be developed further on in this description.

As shown most clearly in FIGURE 3A, the housing 10 and the key plug 14 are each provided with a plurality of pin tumbler elements which are slidably carried within the various holes of the housing and key plug for movement within the various holes of the housing and key plug, and for movement within the bores formed by alignment of the holes of the key plug 14 with the holes of the housing 10. The pin tumblers or elements shown in FIGURE 3A for use in the preferred embodiment of the invention comprise: primary or key contacting elements 30 carried one within each of the holes in

rows

20 and 20 of the key plug 14; locking elements 31 carried one within each of the holes in rows 12 and 12' of the housing 10; driver elements 33 carried one within each of the holes in

rows

13 and 13 of the housing 10; transferable, intermediate or secondary elements 32 carried initially in the holes of

rows

20 and 20 of the key plug 14; oppositely disposed key contacting elements 53 (see also FIGURE 15) normally carried within respective bores formed by alignment of hole 25 with hole 28 and alignment of hole 25 with hole 28' (FIGURE 2); and a pair of oppositely-disposed locking elements 54, one carried within the hole 50 and one carried within the hole 50 of the housing 10.

The locking elements 31, the driver elements 33, and the locking elements 54 are arranged to be biased inwardly toward the key plug 14 by means of compression springs 36. As shown in FIGURES 1 and 3, the means for enclosing the outer ends of all of the tumbler holes in the housing 10 may comprise four substantially thin elongated plates 37, each of which slides inwardly in a manner well known in the lock art, into longitudinal .8 grooves or slots provided adjacent each side surface of the housing 10 (see also FIGURES 16 to 18). Thus, all of the spaced-apart holes that open outwardly on a respective surface of the housing 10 may be capped over by a single elongated plate 37 which slides into position from the rear of the housing 10 and toward the face end thereof and provides a bearing surface for the outer ends of the springs 36 contained therebeneath within the housing 10.

It is emphasized that all of the primary or key contacting tumblers 30 utilized in the lock construction are of different or varying lengths as compared one to another, and all of the intermediate tumblers 32 are also of slightly different comparative lengths. Each of the primary tumblers 30, at its inward key-contacting end, is preferably provided with a pointed end configuration so that the tumblers will not catch or bind on the blade edge of a key inserted therepast.

(B) Operation of the lock assembly With reference to the preferred embodiment of the invention illustrated in the drawings, FIGURE 1 shows that the key plug 14 is revovable during its normal operation from a first operating position or locked position X wherein the long dimension across the keyway slot 17 is disposed vertically, clockwise through an arc of approximately to a second operating position or unlocked position Y. When it is desired to reset or change over the lock assembly 8 for operation by a successive operating key, the key plug 14 is revolved clockwise from a locked position through an arc of to a third operating position or reset or changeover position denoted by line Z in FIGURE 1, however, such rotation of the key plug 14 past the unlocked position Y is impossible during the normal operation of the assembly 8 until a key plug limiting means that acts normally to prevent rotation of the key plug past the unlocked position Y is released by means of a special releasing or priming operation as will be explained more fully hereafter.

In FIGURES 4 through 10, which are provided to demonstrate the normal operation of the lock assembly 8, explanation will be largely confined to that which occurs with respect to the row 20 of holes in the key plug 14 and

rows

12 and 13 in the housing 10, inasmuch as the inner action of elements which occurs with respect to rows 20' of the key plug 14 and

rows

12 and 13 of the housing'10 is substantially the same, the only difference being in the combination of pin tumbler elements selected by a key blade inserted in the keyway slot 17. Details of the rear area of back end region of the housing 10 and the key plug 14 are purposely excluded from FIGURES 4 through 10 because the elements in the rear area are not involved in the normal function of the lock assembly by use of an operating key.

When the various separate elements as shown in FIG- URE 3A are initially assembled to an operable unit, the upwardly disposed row 12 of holes in the housing 10 would appear internally as shown in FIGURE 4, and the horizontally disposed holes of row 13 would appear as shown in FIGURE 5. FIGURES 4 and 5 show that, prior to setting of the lock assembly for operation by a first operating key, the key plug is disposed with respect to the housing 10 with its keyway slot 17 turned horizontally in alignment with the horizontal reset line Z of FIGURE 1. Thus, the holes 20a through 2% of the key plug 14 are in aligned communication to form bores with holes 13a through He of the housing 10.

Each hole of the row 20 contains both a key-contacting or primary element 30 having its pointed inner or keycontacting end resting against one of the longitudinal key guide ridges within the keyway slot 17, and an intermediate or transferable element 32 in registration against the outer end of the key-contacting element 30. In each hole of the row 20, the combined length of the key-contacting element 30 and the intermediate element 32 con- 9 tained therein is such that the outer flat surface of the intermediate element 32 is flush with the shear line 34. FIG- URE also shows that each of the holes of row 13 contains a driver element 33 and a compression spring 36 biasing the driver element 33 inwardly toward its adjacent intermediate element 32.

With the key plug 14 initially disposed at the re-set position Z, FIGURE 4 shows that the holes of row 12 in the housing each contain locking elements 31 with a compression spring 36 urging them against the outer surface of the key plug 14.

With the various elements disposed as shown in FIG- URES 4 and 5, the lock assembly 8 is ready to be set for operation by a first operating key. FIGURES 8 and 9 show an operating key 40 having a head portion 40a and a blade 40b. The blade 40b is provided with longitudinal grooves such as 400 to engage upon and ride inwardly on the longitudinal laterally protruding

guide ridges

18 and 19 within the keyway slot 17.

A slightly widened neck portion 402, which abuts against the front surface of the key plug 14 when the key blade 40b is inserted into the keyway slot 17, determines the depth of blade insertion therein. The blade 40b has an edge 40d thereof bitted or cut in the customary pattern of longitudinally successive peaks and valleys whereby certain of the key-contacting elements 30 will be contacted and caused to move outwardly from the key plug 14 while the remaining key-contacting elements 30 slip downwardly into the valleys along the edge of 40d and thus regain their original position as shown in FIG- URE 5.

Each of the key-contacting elements 30 that is thus urged outwardly, as shown in FIGURE 9, causes an intermediate element 32 in registration therewith to move outwardly into the housing 10 a distance such that the point of registration between the intermediate element 32 and the key-contacting element 30 coincides with the shear line 34. Therefore, with the key 40 positioned within the key plug 14, as shown in FIGURE 9, the key plug 14 may be rotated counterclockwise to the locked position X as shown in FIGURE 1.

FIGURE 8 shows the internal appearance of some of the various parts of the lock assembly 8 after the key plug 14 has been rotated counterclockwise from the reset position Z to the locked position X. By comparing FIG- URE 8 to FIGURE 9, it will be seen that, during such rotation, certain of the intermediate elements 32 traveled within and were transferred by the key plug 14, while other intermediate elements 32 were deposited in the holes of the row 13 where they remained when the key plug 14 was rotated away from the reset position Z.

More specifically, FIGURE 9 shows that the insertion of the key blade 40d into the keyway slot 17 caused intermediate elements 32 to move into the housing 10 in rows 13a, 13c, and 132. Holes 13b and 13d did not receive intermediate elements from the key plug 14, and rotation of the key plug 14 away from the position shown in FIGURE 9 resulted in travel of intermediate elements 32 contained in holes 20b and 20d with the rotated plug 14.

With the key plug 14 disposed in the locked position X, the arrangement of parts of the lock assembly 8 with respect to row 13 will appear as in FIGURE 7. All that is needed to lock the key plug 14 in relation to the housing 10 is the withdrawal of the key 40 from the keyway slot 17 (as shown in FIGURE 8), whereby locking elements in holes 12a, 12c, and 122 will be urged downwardly (as shown in FIGURE 6) across the shear line 34 to prevent rotation of the key plug 14, as shown in FIGURE 6, where the key plug is in the locked position with respect to the housing 10.

Having heretofore described the movement and inner action of parts of the lock assembly 8 during the operation of its setting for operation by a first operating key, it is believed that such interaction of parts may be more clearly understood by consideration of the same operation with respect to one of the holes in row 13 and its circumferentially aligned counterpart hole in row 12 of the housing 10. FIGURE 16, which is a front elevational view of the lock assembly in vertical section, may be considered as illustrating the relative positioning of pin tumbler elements in the horizontally disposed hole 13a of row 13 (as shown in FIGURE 9) and the vertically disposed hole 12a of row 12 (as shown in FIGURE 8). FIGURE 16 shows the key plug 14 disposed at the reset or key changeover or third operating position. Insertion of the blade of an operating key will thus set the lock assembly 8 for operation by such key. When the operating key blade is fully inserted into position Within the keyway slot 17, the key-contacting element 30 will move outwardly toward the housing 10, causing the intermediate element 32 and the driver element 33 to move outwardly also. The adjacent ends of the key-contacting element 30 and intermediate element 32 come into alignment with the shear line 34 so that the key plug 14 may be turned counterclockwise away from the reset position, as shown in FIGURE 17. A full turn from the reset position in a counterclockwise direction places the key plug 14 in the locked position, with stop means located at the rear of the housing 10 acting to prevent the key plug 14 from turning counterclockwise beyond the locked position. The operating key can then be withdrawn from the lock assembly 8 and the locking element 31 will be pushed downwardly by its adjacent spring 36 across the shear line 34, to bind the key plug 14 with respect to the housing 10, as shown in FIGURE 18.

The successive movement of pin tumbler elements as illustrated in FIGURES 16, 17, and 18 may be considered as representative of the action that takes place in holes 1301, 13c, and 13s of FIGURE 9 and respectively aligned holes 12a, 12c, and 12a of FIGURE 8 when the operating key 40 is utilized to set the lock assembly 8.

When the movement of pin tumbler elements as shown in FIGURES l6, l7, and 18 is taking place within bores formed by alignment of the aforementioned holes, the intermediate pin tumbler elements 32 within key plug holes 20b and 20d are carried in and with the rotated key plug 14. Thus, with continued reference to FIGURES 8 and 9, the intermediate elements 32 shown within the holes 13a, 1150, and 132 may be considered as deposited pin tumbler elements, whereas the intermediate elements 32 carried within the holes 2017 and 20d, as shown in FIGURE 8, may be considered as transferred pin tumbler elements. Subsequent setting of the lock assembly 8 for operation by an operating key having a different blade configuration as compared to operating key 40 will affect a corresponding change in the combination of transferred and deposited intermediate elements (as shown, for example, by FIGURE 10).

As in the operative concept of any pin tumbler lock mechanism, the length of the various pin tumbler elements in my lock assembly are preferably varied so that the length of key-contacting elements 30 are respectively different with respect to each other. In a like manner, intermediate elements 32 would be of varying length as compared to each other. Locking elements 31 as well as driven elements 33 will normally be of the same length, but may be varied where desirable. Locking elements 54 may be slightly longer than locking tumbler elements 53 to accommodate the thickness of ring 26 (see FIGURE 11).

FIGURE 6 shows the lock assembly 8 in the locked position and capable of being repeatedly operated, or unlocked and relocked, by inserting the key blade 40]; of the key 40 into the keyway slot 17 and manipulating the key to turn the key plug 14 accordingly. The lock assembly 8 is thus set for normal operation by the operating key 40, and only key 40 or a master key will operate the lock assembly until such time as the assembly is re-set for operation by a different operating key.

During the normal operation of the lock assembly 8 by means of the operating key 40, the key plug 14 cannot be turned clockwise beyond the open or unlocked position Y because of a key plug limiting means broadly comprising the key plug end plate 21, the finger-like projection 430 of the eccentric plate 43, and the extended lug 27 of the ring 26 as shown in FIGURES 11, 12, 13 and 13A. As shown in FIGURE 12, when the lock assembly 8 is unlocked by inserting the blade of the proper operating key and revolving the key plug 14 toward the unlocked position (counterclockwise as viewed in FIGURE 12), the radially disposed striking edge 21a of the end plate 21 moves in an upward direction through an arc of approximately 80 whereupon it contacts the side surface of the finger-like projection 430 of the eccentric plate 43. The eccentric plate 43 is prevented from moving to the left by its contact with the lug 27 of the ring 26, and the lug 27 is prevented from moving to the left by the side wall of the slot-like opening 22b through which the lub 27 is extended from the ring 26.

During normal operation of the lock assembly by use of an operating key, the ring 26, as shown in FIGURES 2 and 11, remains stationarily fixed with respect to the housing due to oppositely disposed locking elements 54, each of which extends across a shear line 38 defined by adjacent surfaces of the ring 26 and the side wall of the bore 11. The inner end of each of the locking elements 54 is normally flush with a shear line 35 defined by adjacent surfaces of the ring 26 and the key plugs back end portion 16. Therefore, the key plug 14 is normally free to rotate within the stationary positioned ring 26 as shown in FIGURE 11, and the key-contacting elements 53 carried within the respective holes 25 and 25' of the key plug are carried normally along with the rotating key plug 14 between the locked and unlocked positions. The

elements

53 and 54 may be termed tumbler latching pins or elements which operate within cooperating tumbler-receiving hole portions in the ring 26, the housing 10 and the key plug 14.

As shown in FIGURE 14, a master key 42 is provided in the combination of this invention to operate the lock assembly 8. The master key 42 is adapted to be capable of unlocking the lock assembly at all times. The master key 42 comprises a head portion 420 and an extended blade 42b. The blade 42b is grooved on each flat side thereof to provide guide grooves such as 42c.

The blade 42b is shown as having its opposite longitudinal edges cut with a pattern of peaks and valleys which combine, on one key blade, all the various different patterns which would appear on all of the keys in the plurality of operating keys to which the lock assembly 8 is successively adaptable.

Thus, no matter what combination of pin tumblers has been selected in accordance with the particular configuration of a specific operating key, the outer ends of all of the primary or key-contacting tumblers 30 will be moved into alignment with a shear line 34 by the master key blade so that the key plug 14 can be revolved from the locked to the unlocked position.

To reset or change over the lock assembly 8 from operation by a first operating key to sole operation by a second operating key, it is first necessary to disengage or release the aforementioned key plug limiting means. In other words, with reference to FIGURE 12, the fingerlike projection 430 which extends downwardly in the path of the radially disposed striking surface 21a of the plate 21 to limit the arc of rotation of the key plug 14 to 80, must be caused to move out of the path of such rotation to a new position as shown in FIGURE 13. Movement of the lug 27 (to the right as shown in FIGURE 12) against the projection 43c is the means of turning the eccentric plate 43 to the position shown in FIGURE 13 and thereby moving the projection 43 out of the path of the rotatable end plate 21.

Inasmuch as the ring 26 is normally bound to the housing 10 (as shown in FIGURE 11) by the extension of the locking elements 54 across the shear line 38, it is first of all necessary to free the ring 26 in a clockwise direction as viewed in FIGURE 12. The foregoing actions occur as part of the reset or changeover operation of the lock assembly 8.

The reset or changeover operation begins with the first step of withdrawing the first operating key from the lock while the key plug 14 is disposed at the locked position X as shown in FIGURE 1. Next, a special control, reset or release key 51 (FIGURE 15) is utilized to prime the lock for resetting by releasing the key plug limiting means. The blade 51a of the control key 51 is similar to the blade 42b of the master key 42 insofar as the blade edge configuration of the master key 42 is duplicated on the blade of the control key 51. However, the control key 51 has an elongated blade 51a adapted to extend into the rear region of the lock assembly 8 to contact and move outwardly the key-contacting pin tumbler elements 53. Such movement causes the locking elements 54 to move outwardly into the housing 10 so that the inner ends thereof are in respective alignment with the shear line 38, while the key-contacting pin tumblers 53 are each extended across the shear line 35. With the

pin tumblers

53 and 54 thus positioned as shown in FIGURE 15, the ring 26 is no longer prevented from movement with respect to the housing 10 but is now in a bound relation with respect to the back-end portion 16 of the key plug 14.

The key plug 14 may now be rotated counterclockwise (as viewed from the face of front end of the lock assembly 8) by manipulation of the head of the control key 51 to a release position R as shown in FIGURE 19. Such rotation causes the ring 26, and its integral lug 27, to rotate so that the lug 27 moves transversely to the right and across the slot 22b (as viewed in FIGURE 12). By such movement, the lug 27 pushes the finger-like projection 430 and thereby causes the eccentric plate 43 to revolve on the pin 43a in a counterclockwise direction. As the eccentric plate 43 revolves, the upper projection 43!) will simultaneously move counterclockwise along the pawl 45 into latching engagement with 45b (see the position of FIGURE 13).

An edge portion of the eccentric plate 43, adjacent the projection 43b, is shaped in a manner to cooperate with the upper end of the pawl 45 so that the projection 43b will slide beneath the downwardly facing edge 45b (FIG- URE 13A) of the pawl 45. The edge portion 45b functions to engage the finger-like projection 43b and hold the plate 43 in its revolved position. With the eccentric plate 43 thus held, the projection 43c thereof is held out of the path of movement of the end plate 21 and is no longer in a position to contact the striking edge 21a when the key plug 14 is rotated. Thus, the key plug limiting means is quite simply released or disengaged by use of the control key to rotate the key plug to the position R (FIG- URE 19), after which the key plug 14 may be returned to the locked position and the control key 51 removed from the lock assembly 8.

The next step in the reset operation is reinsertion of the blade of the first operating key which will, as shown in FIGURE 8, unlock the key plug 14 so it may be rotated away from the locked position. Now, with the eccentric plate 43 positioned as shown in FIGURE 13, the key plug 14 may be rotated, by manipulation of the operating key, toward and past the unlocked position to the third operating position or reset position Z.

As shown in FIGURE 13, with the projection 430 no longer preventing the complete 90 rotation of the plate 21, the key plug 14 may be returned, by manipulation of the operating key for which the assembly is set, to the reset position Z so that the holes of row 20 in he key plug 14 come into aligned communication with the holes of row 13 of the housing 10 (such as shown in FIG- URE 9). Then, by withdrawing the operating key from the lock assembly 8, the pin tumbler elements as shown in FIGURE 9 will be permitted to resume the positioning shown in FIGURE 5. It is emphasized that the key plug 14 can only be returned from the locked position X to the reset position Z by use of the sole operating key to which the lock assembly was previously operable immediately prior to use of the control key.

When the plate 21 is turned counterclockwise, its ledge or point 21d will not engage finger or rod 47 with the pawl 45 in the forwardly sloped position of FIGURE 12. However, when the pawl 45 is in the upright position of FIGURE 13, a clockwise rotation of the plate 21 and its point 2101' will cause an engagement of the latter with the finger or rod 47 to tilt pawl 45 counterclockwise and release engagement of 45b with 43b. As a result, the elements will be returned to the position of FIGURE 12.

FIGURE 10 shows how the lock assembly 8 is now reset by insertion of the blade 41b, which has a distinct and different blade edge configuration 41d as compared to blade 40d of the first operating key 40 and which effects a selection or combination of elements in accordance with its distinct blade edge configuration. Whereas the first operating key 40, as shown in FIGURE 9, caused intermediate tumblers 32 to move upwardly into the housing 10 within holes 13a, 13c, and 132, the distinct blade edge configuration 41d effects the selection of its own pin tumbler combination and causes a new combination of intermediate elements 32 to move upwardly into the housing 10 in holes 13b and 13c but not in holes 1312, 13d, and 13a.

When the key 41 is turned to rotate the key plug 14 back to the locked position, the key plug limiting means is automatically, by such rotation, reengaged to prevent the key plug from being subsequently turned past the unlocked position during the normal operation of the lock assembly 8 by the second operating key 41.

When the key 41 is withdrawn from the keyway slot 17, with the key plug 14 at the locked position, locking tumblers 31 in holes 12b and 120 will move downwardly across the shear line 34 to bind the key plug 14 to the housing 10. Reinsertion of the blade 40b of the first operating key 40 (or blade of any operating key other than the second operating key 41 for which the lock assembly is now set) Will not operate to unlock the key plug with respect to the housing and permit its being turned to the unlocked position.

Returning the key plug 14 from the reset position Z to the locked position by manipulation of the second operating key 41 has the effect of rotating the plate 21 from the position as shown in FIGURE 13 back to the position shown in FIGURE 12. During such movement of the plate 21, the striking edge 21b thereof moves upwardly and comes in contact with the extended end 47a of the pivot rod 47. As shown in FIGURES 12, 13, and 13A, the pivot rod 47 is rotatably mounted with respect to the pawl 45 so that a pushing force directed against the rod end 47a from the right will cause the rod 47 to pivot on the pin 45a in a clockwise direction. After such force is removed, the spring 49 will draw the end 47b downwardly and thus cause the rod 47 to resume its original position at rest against the pin 48.

Since the pivot rod 47 is prevented from pivoting counterclockwise upon the pawl 45 by the stop pin 48, the rod 47 will effectively act as a lever and cause the pawl 45 to pivot backwardly in a counterclockwise arc and thus move away from and release the finger-like projection 43b so that the eccentric plate 43 may be returned, by the biasing action of spring 44, to the original normal position shown in FIGURE 12.

Thus repositioned, the projection 43c will again act to prevent the key plug 14 from being rotated past the unlocked position until such time as the control key 51 is again utilized to release the key plug limiting means as heretofore described.

During the phase of the operation of the assembly 8 when it is being changed over or reset from a first operating key to operation by a second operating key, it is important that special means be provided so that the master key cannot be inadvertently used in place of the first operating key in order to turn the key plug 14 to the reset position Z. Thus, as shown in FIGURE 14, the master key 42 is provided with a substantially wide neck portion 42d, as compared to the neck portion 40:: or 41s of the operating key 40 or operating key 41, as shown respectively in FIGURES 8 and 10. Also, as shown in FIG- URE 1, a small outward projection or lug 29 integral with the face or front surface of the housing 10 is provided to engage the underside of the neck portion 42d of the master key and prevent it from being turned past the unlocked position Y to the reset position Z. Cooperative functioning between the projection 29 and the neck portion 42d of the master key 42 is necessary to insure that a person not entirely familiar with the reset operation of the lock assembly will be able to only utilize the operating key for which the lock assembly is currently set to turn the key plug to the reset position.

The projection 29 is a stop means for the master key only and in no way will interfere with the use of the operating keys in the assembly. Each of the operating keys provided for the lock assembly 8 will have a neck portion configuration the same as 40e of key 40 or 41e of key 41 so as to permit the operating key head to be rotated freely past the projection 29 during the reset operation of the lock assembly 8.

It is understood that the invention shown and described herein is not limited to the structure of the preferred embodiment emphasized for the purpose of illustration, and that various modifications and changes may be made within the scope of the invention. For example, the number of holes utilized for forming pin tumbler bores in the lock assembly 8 can be varied, i.e., increased or decreased.

It will also be possible to eliminate the rear plate 22 of the housing 10. This would be accomplished by pro viding a slot opening similar to 22b as a recess in the rear housing wall, and in such a construction, the various parts shown in FIGURE 12 which now are mounted on the rear plate 22 would be connected directly to the body of the housing 10.

Also, a more simplified embodiment of the invention may be constructed by excluding the rows 12' and 13' in the housing and row 20' in the key plug 14. In such a simplified embodiment, each key utilized therewith would have only a single cut blade edge configuration rather than the oppositely disposed cut blade edges as required for operation of the preferred embodiment shown.

Neither is it intended that the number of pin tumbler holes and the associated pin tumblers carried therein in the back-end portion 16 of the key plug and the ring 26 be limited to those as shown in FIGURE 2. Rather, a salient feature of the invention is that a number of lock assemblies can be built in accordance with the invention, with each requiring a respectively different control key for use in priming the lock for resetting from one operating key to another. One such modification would involve providing, in each lock assembly, that the back-end portion of thekey plug 14 be lengthened to support a correspondingly widened ring 26 so that a plurality of longitudinally spaced-apart pin tumbler holes could be provided in both the back-end portion 16 and the ring 26 in addition to the

holes

25, 25', 28 and 28' shown in FIGURE 2. Then, in each lock assembly of a number of such lock assemblies, release of the key plug limiting means would require a control key having a distinct and specific key blade configuration corresponding to the particular arrangement and size of pin tumblers in the rear portion of the lock assembly.

Since the foregoing modification might involve a lock assembly having too great a longitudinal elongation for a specific intended use, an alternate means of getting a similar effect would be to provide a plurality of lock assemblies as illustrated in the drawing and varying the length of the

pin tumbler elements

53 and 54 utilized in the various lock assemblies. In such an event, the ring 26 may be made of increased thickness to contain the pins. Thus, although the lock assemblies in the plurality would be alike in all other respects, each lock assembly could only be primed for the changeover operation by means of a specific control key having an edge configuration at the blade end thereof adapted to operatively correspond with the length and/or number of pin tumbler elements carried in the opposed bores formed by the aligned

holes

50, 28 and 25 and aligned

holes

50, 28 and 25'.

It is anticipated that a lock assembly constructed in accordance with this invention would be preset when the lock assembly is initially assembled for distribtuion and sale. It is believed that such presetting of a lock assembly for operation by one of the operating keys made available therewith would simplify use and understanding of the lock assembly by the purchaser.

To broadly compare the lock assembly of this invention to the prior art, a conventional pin tumbler lock, as a person skilled in the lock art is aware, comprises a housing, usually of a cylindrically shaped sleeve-like configuration, having one longitudinal row of pin tumbler element holes equidistantly spaced end to end on the housing and extending inwardly to the central bore thereof which supports a rotatable key plug therein. The key plug of the conventional pin tumbler lock has a row of pin tumbler holes communicating with its keyway slot, with such holes being alignable, by rotation of the key plug, with the pin tumbler holes in the housing. A shear line is defined by adjacent surfaces of the housing and the cylindrical side wall of the key plug, and the key plug is rotatable, by means of an operating key, between locked and unlocked positions when the blade of the key is inserted to cause locking pin tumblers extending across the shear line to move away from the key plug so that the ends of the locking pin tumblers align with the shear line and free the key plug for rotation.

The length of the pin tumbler elements utilized in the conventional lock are scaled in accordance with the particular configuration of the operating keys blade. Therefore, the greater the number of alignable holes in the housing and key plug, the greater number of available bores that can be utilized to organize respectively different pin tumbler combinations. It is often the practice, when it is desired to multiply the number of available pin tumbler bores, to utilize an operating key having both narrow edges of its blade bitted or cut and provide the key plug and housing with an additional row of pin tumbler holes which are alignable to form additional oppositely disposed bores when the first rows in the key plug and housing are in aligned communication. In either the simpler form of lock where only one row of pin tumbler holes is provided in the key plug and housing, respectively, or, in the more sophisticated construction where second rows are provided, the lock can only be rekeyed for operation by a different operating key by disasembling the lock and changing the arrangement of pin tumbler elements in accordance with the configuration of the second operating key.

Briefly comparing the lock assembly 8 of this invention to the aforementioned conventional construction, FIGURE 3A shows that a housing 10 is included that could alternatively be of the more familiar sleeve-like configuration. Included also is a rotatable key plug 14 that is supportably carried in a central opening or bore 11 through the housing 10. The housing 10 is provided with a row 12 of equidistantly spaced-apart pin tumbler holes, with each hole extending from the outer surface of the housing 10 and radially inwardly toward the axis of the bore 11. As in the aforementioned conventional construction, row 12 is provided to slidably contain a locking tumbler 31 within each of its respective holes, at least some of which will extend across the shear line (shear line 34 as shown in FIGURES 5 and 6) defined by the adjacent surfaces of the key plug '14 and the inner wall of the bore 11. The locking pin tumblers 31, which are biased inwardly toward the key plug by means of compression springs 36, are arranged to move inwardly across the shear line and into pin tumbler holes of a corresponding row 20 provided in the key plug 14 (as shown in FIGURE 2). The locking pin tumblers 31 move inwardly when the key plug is disposed in its locked position relative to the housing 10 so that holes of row 20 are in aligned communication with the respective holes of row 12.

As in a conventional pin tumbler lock, the lock assembly in accordance with this invention may include a row 12' of pin tumbler holes, oppositely disposed with respect to the row 12, to slidably contain additional locking elements 31. Therefore, a row 20' (FIGURE 2) of pin tumbler holes in the key plug 14 would be provided to form additional bores by alignment with the holes of the row 12. Inclusion of the row 12 in the housing 10 multiplies the number of possible different pin tumbler combinations and increases the number of operating keys to which the lock can be selectively adapted.

Unlike the conventional tumbler lock, the housing 10 in accordance with this invention is provided with at least a second offset row 13 of equidistantly spaced-apart and horizontally aligned pin tumbler holes extending radially-inwardly toward the axis of the opening 11. The row 13 serves in a cooperative relationship to the row 12 in the key change over operation of the lock assembly, but does not serve any function in the normal operation of the lock assembly 8 when the key plug is revolved between the locked and unlocked positions.

When, as shown in FIGURE 3A, the row 12 of the pin tumbler holes is provided in the housing 10 for communication with the row 20' of the key plug 14, then a row 13 of pin tumbler holes in the housing 10 is also provided in an offset position to row 12', to serve in a cooperative relation with the row 12 in the key changeover operation. From the foregoing description, a person skilled in the art will understand that the

rows

12 and 13 of the housing 10, and row 20' of the key plug 14, would not be required for use of operation of the lock assembly 8. Exclusion of these rows of holes would not detract from the inventive concept disclosed herein. The provision of the rows 12', 13' and 20 permits a correspondingly greater number of operating keys to which the lock assembly may be adapted, just as the provision of additional holes in each row, to form a larger plurality of tumbler bores, would allow for a correspondingly greater number of operating keys in the assembly.

Not only does the lock assembly 8 in accordance with my invention not necessarily require the provision of the

rows

12, 13, in the housing 10 and row 20' in the key plug 14, it is also not required that the rows of holes shown in the preferred embodiment be disposed in a quadrant relationship, i.e., each at a right angle to an adjacent row (as shown in FIGURE 3). For example, the row 13 of pin tumbler holes in the housing 10 could be radially disposed with respect to the axis through the bore 11 in much closer proximity to the row 12, so that rotation of the key plug 14 from the locked to the reset position would then only require a short are such as 30 as compared to the arc of rotation required in the construction as shown in FIGURE 3. Such change in the positioning of row 13 relative to the row 12 would necessitate a corresponding change in the positioning of row '13 inasmuch as row 13' must be oppositely disposed from the row 13 so that two sets of opposed bores are simultaneously formed when holes of the key plug 14 are respectively aligned with the opposed row 13 and 13' of the housing 10. It is also considered apparent that any changes, such as repositioning of the rows 17 13 and 13" with respect to the

rows

12 and 12 of the housing 10, will necessarily require changes or modifications of other parts or elements of the lock assembly.

It is not considered necessary to show or describe in detail the additional apparatus which would be used in combination with my lock assembly in order to enable its function as a door lock mechanism. As with conventional pin tumbler locks, the adaptation of my lock assembly for such use will include the provision of a connecting rod positioned as an extension of the axis of the key plug 14, with the end of the connecting rod engaged to the back of the keyway slot 17 whereby the rotation of the key plug 14 would effect axial rotation of the connecting rod. Thus, when the key plug 14 is turned to the open position, such movement is translated through the connecting rod to means provided to translate the rotative motion of the connecting rod to a withdrawal motion of a latch bar away from a striking plate mounted on the door jamb, and turning the key plug 14 back to the locked position will have the effect of releasing the latch bar so that it will be urged outwardly by spring means to engage the striking plate on the door jamb and secure the door thereto.

Having heretofore described my invention for an improved pin tumber lock assembly, reference is made to FIGURE where it will be seen that when the key plug 14 is at the reset position, without the blade 40b of the operating key 40 inserted within the keyway slot 17, the key plug 14 is not prevented from rotating back toward the locked position, inasmuch as none of the pin tumblers of the lock assembly extend across the shear line 34 to bind the key plug with the housing Therefore, it is realized that insertion of a sharp pointed instrument a short distance within the keyway slot 17 and thereafter twisting the instrument would effect rotation of the key plug 14 away from the reset position Z and toward the locked position X (as shown in FIGURE 1).

If it is considered necessary, a means to prevent such rotation of the key plug 14 from the reset position may be quite simply provided. One means for preventing such rotation is by removal and elimination from the lock assembly of one of the intermediate pin tumblers 32 so that the driver pin tumbler element now adjacent thereto will be urged downwardly to extend across the shear line 34 and register with the primary element 30 carried therebelow in the key plug 14. Thus, the driver pin tumbler element urged downwardly in place of the removed intermediate element 32 will serve as a special locking element to prevent free rotative movement of the key plug from the reset position Z. In accordance with such change in pin tumbler arrangement, each of the operating keys provided for the lock assembly 8 would be modified so as to be able, when used in the lock assembly 8, to cause the single special locking pin tumbler element to move outwardly so that its inner end would align with the shear line 34 and permit the key plug 14 to be rotated in a counterclockwise direction. Therefore, each operating key would have a portion of its blade edge identical to all other operating keys, with such portion being a peak therealong that is provided to engage and urge outwardly the key-contacting or primary element 33 that is in registration with the aforementioned special locking element. The remaining portion of the blade of each operating key would, of course, be dissimilar to each of the other operating keys so as to effect, when used in the lock assembly 8, a choice of operative pin tumbler elements in a combination distinct and peculiar thereto.

I claim:

1. In a pin tumbler lock having a housing rotatably carrying a key plug therein and defining a shear line therewith wherein, the key plug has a keyway slot therealong and a row of tumbler-receiving hole portions extending from the shear line to the keyway slot, a pair of rows of tumbler-receiving hole portions are positioned in an angularly spaced-apart relation in the housing for alignment with the rows of the key plug when the plug is turned about the shear line within the housing; pin tumbler elements are provided and include driven elements for sliding movement within the tumbler-receiving hole portions of the housing, key contacting elements for sliding movement within the tumbler-receiving hole portions of the key plug, and transferable tumbler elements for sliding movement across the shear line and between the tumbler-receiving hole portions of the key plug and of the housing when the row of hole portions of the plug are in alignmentwith a row of hole portions of the housing, the improveipent which comprises: releasable position limit means cooperating with the key plug and the housing for normally limiting movement of the key plug between locking and unlocking positions, a reset control key, and means carried by the key plug and the housing for engagement by said reset control key for releasing the position limit means to permit rotation of the key plug beyond its normal locking position to a resetting position.

2. In a pin tumbler lock as defined in claim 1, said position limit means comprising a ring rotatably mounted within the housing and on the key plug, a lug projecting from said ring, an end plate secured on the key plug and having a pair of circumferentially spaced-apart ledge portions and a curved notch portion therebetween, and said end. plate being adapted to be turned with said key plug during normal turning movement of the key plug between a locking position at which said lug is in engagement with one ledge portion and an unlocking position at which said lug is in engagement with the other ledge portion.

3. In a pin tumbler lock as defined in claim 2, the housing, the key plug and said ring having cooperating tumbler-receiving hole portions with respect to each other, said release means comprising tumbler latching elements slidably carried for movement within the cooperating hole portions and being normally positioned to extend across the shear line between said ring and the housing and in alignment with the shear line between said ring and the key plug whereby relative rotative movement of said ring is prevented with respect to the housing and'is permitted with respect to said key plug, and said tumbler latching elements being moved into alignment with the shear line between said ring and the housing and across the shear line between said ring and the key plug when said reset key rotates the key plug to the resetting position whereby the ring may thereafter be rotated by the key plug with respect to the housing.

4. In a pin tumbler look as defined in claim 2, an eccentric element pivotally mounted on the housing, said eccentric element having a finger projection normally engaging said lug during turning movement of the key plug between the locking and unlocking positions, and said eccentric element being adapted to be moved into a released position with respect to said lug by turning the key plug with the reset key from the locking position to an initial resetting position to permit the key plug to be rotated past the unlocking position to a second resetting position.

5. In a pin tumbler look as defined in claim 1, cooperating ring, lug and notched plate means comprising said position limit means.

6. In a pin tumbler lock as defined in claim 5, said plate means being secured on the key plug, said ring being mounted between the housing and the key plug, and said lug being secured to project from said ring.

7. In a pin tumbler lock as defined in claim 6, said ring, the housing and the key plug having cooperating alignable tumbler-receiving hole portions, said release means having tumbler latching elements slidably-operatively mounted for movement within said cooperating hole portions to extend across a shear line between said ring and the housing when the key plug is being normally turned between locking and unlocking positions, and said tumbler latching elements being adapted to align with the shear line between said ring and the housing when the key plug has been moved to the resetting position by said reset key and is thereafter turned in a reverse direction from the resetting position to the locking position, and means actuated by said lug during movement of said key plug to the resetting position for permitting said key plug to thereafter be moved from the locking past the unlocking positions to a final resetting position at which a service key may be inserted within the keyway slot to reset the lock for normal locking and unlocking movement by such service key.

8. In a pin tumbler lock as defined in claim 1, a master key having offset portions to cooperate with the pin turnbler elements upon insertion within the key plug for rotating the plug between the locking and unlocking positions when the device is set for operation by one of a group of operating keys, and means carried by the housing for preventing said master key from rotating the plug from the locking position past the unlocking position and to a second resetting position after said reset control key has moved the plug to the locking position from the first mentioned resetting position.

9. In a pin tumbler lock as defined in claim 1, said position limit means being rotatably mounted within the housing and on the key plug and having cooperating tumbler-receiving hole portions with the housing and the key plug, said release means having tumbler latching elements slidably carried for movement with the cooperating hole portions, said tumbler latching elements normally extending across a shear line between said position limit means and the housing, and said tumbler latching elements being moved into alignment with the shear line between said position limit means and the housing when said reset control key rotates the key plug to the resetting position.

10. In a pin tumbler lock having a housing rotatably carrying a key plug therein and defining a shear line therewith wherein, the key plug has a keyway slot therealong and a row of tumbler-receiving hole portions extending from the shear line to the keyway slot, :1 pair of rows of tumbler-receiving hole portions are positioned in an angularly spaced-apart relation in the housing for alignment with the row of the key plug when the plug is turned about the shear line within the housing; pin tumbler elements are provided and include driven elements for sliding movement within the tumbler-receiving hole portions of the housing, key contacting elements for sliding movement within the tumbler-receiving hole portions of the key plug, and transferable tumbler elements for sliding movement across the shear line and between the tumbler-receiving hole portions of the key plug and of the housing when the row of hole portions of the plug are in alignment with a row of hole portions of the housing, the improvement which comprises: a position retaining ring operatively mounted on the key plug and having a movement limiting lug projecting therefrom; the key plug, the housing and said ring having cooperating tumbler-receiving hole portions; tumbler latching elements operatively positioned in the cooperating hole portions for sliding movement therein, cam means operatively carried on the housing and cooperating with said ring for engagement by said lug for normally limiting turning movement of the key plug and said ring, a reset control key for insertion in the slot of the key plug and having an oflset portion for engaging said tumbler latching elements and moving them from a normal aligned relation with a shear line between said ring and the key plug to a resetting aligned relation with a shear line between said ring and the housing whereby said key plug and said ring may be rotated from a locking position to an initial resetting position by said reset control key and from the initial resetting position back to the locking position, a service key for insertion into the key plug for normally rotating the plug between locking and unlocking positions within the housing and, after the defined movement by said reset control key, for rotating the key plug from the locking position past the unlocking position and to a second resetting position at which the row of tumbler-receiving hole portions of the plug are in alignment with the tumbler-receiving hole portions of the other row of the housing, and a second operating key for insertion in the key plug when the plug is at the second resetting position for then resetting the lock for normal operation between locking and unlocking positions by said second operating key.

11. In a pin tumbler lock having a housing supportably carrying and defining a shear line with a key plug that is rotatably positioned therein and provided with a keyway slot therealong, wherein the key plug is adapted to be turned by a first service key within the housing between locked and unlocked positions and vice versa and, after resetting, to be turned by a second service key between locked and unlocked positions and vice versa, and wherein the key plug has at least one radial row of spaced-apart pin tumbler receiving holes open between the keyway slot and the shear line, the improvement which comprises, at least two rows in said housing at said angular spaced locations of spaced-apart pin tumblers receiving holes that are open to the shear line to alternately align with the radial row of tumbler receiving holes in said key plug and define tumbler bores; pin tumbler elements for radial sliding movement within said bores that include driven pin tumblers disposed in the receiving holes of the rows of said housing, key contacting pin tumblers disposed in the receiving holes of the row of said key plug, and transferable pin tumblers adaptably arranged for key-actuated movement between receiving holes of row of said plug and cooperating aligned holes of the rows of said housing, for movement out of the shear line within the receiving holes when the first service key turns said key plug to an unlocked position, and for movement within the receiving holes across the shear line when the first service key turns said key plug to a locked position at which the receiving holes of the row of said plug are cooperatively aligned with the receiving holes of the one row of said housing; cooperating means between said key plug and said housing for limiting turning movement of said key plug with respect to the housing between its locked and unlocked positions, and said driven pin tumblers and transferable pin tumblers being adapted to reset themselves with respect to each other when the second service key is inserted within the keyway slot at a position of said key plug at which the receiving holes of the row of said key plug are cooperatively aligned with the receiving holes of the other row of said housing, whereby said key plug may be then turned between unlocked and locked positions and vice versa by the second service key; said key plug having an extension end portion provided with at least one tumbler receiving hole therein open between the shear line and the keyway slot, a ring element operatively positioned on said end portion for turning movement with respect thereto and has at least one tumbler receiving radial hole therein open to the shear line, a driven pin tumbler operatively carried within the hole of said extension portion for radial sliding move ment therein into and out of the hole of said ring, and said ring carrying said cooperating means for normally limiting turning movement of said key plug between its locked and unlocked positions; said cooperating means comprises: a cam plate secured on said extension end portion of said key plug, said plate having an arcuate slotted portion therealong terminating in stop abutment portions, a cam operatively carried on a back end portion of said housing, a lug projecting from said ring element and cooperating with said arcuate slotted portion of said plate and with said cam for normally maintaining the turning movement of said key plug between its locked and unlocked positions and for releasing it from such limited turning movement when said driven pin tumbler of said ring element is moved to a clearing position with the shear line of said extending end portion of said key plug.

(References on following page) 21 22 References Cited FOREIGN PATENTS UNITED STATES PATENTS 496,449 7/ 195 4 Italy.

396,628 1/1889 Van Hoevenbergh 70337 1,004,904 10/1911 Rfies 39 MARVIN A. CHAMPION, Prlmary Examiner 1,788,834 1/ 1931 Hurd 70337 X 5 ROBERT L. WOLFE, Assistant Examiner 1,796,098 3/1931 Hardy 70385 2,422,600 6/1947 Swanson 70340 US. Cl. X.R.

2,427,837 9/1947 Connell 70383 3,006,179 10/ 1961 Erickson 70129 70 408 3,040,557 6/1962 Jacobi 7o 379 X 10 mg 6 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 42 983 Dated August 26 1969 Inventor(s) Michael A. Evanish It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

[- Column L line 30, after "body" change "of" to --or--;-

line 31, after "configuration" change "or" to --of-; line 58, after "radially" insert inwardly--.

Column 5, line 31 after "width" change "of" to --orline 66, change "vertically' to --vertical--.

Column 6, line #2, correct the spelling of plate". Column 8, line 23, correct the Spelling of "revolvable". Column 1 1 line 20, change "lub" to --lug--. Column 12, line 72 at the end of the line change "he" to --the--.

Column 17, line 1 change "13" to --13'--. Column 11 line 1 change "rows" to --row--. Column 19, line 26, change "with" to --within--. Column 20, line 19, change "tumblers" to --tumbler--.

SI'GNED NND SEALED APR 14-1970 D Attest:

WILLIAM E. sum; JR.

t her EdwardM F18 6 Commissioner of Patents \ttesfing Officer