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Publication numberUS883414 A
Publication typeGrant
Publication dateMar 31, 1908
Filing dateMay 13, 1907
Priority dateMay 13, 1907
Publication numberUS 883414 A, US 883414A, US-A-883414, US883414 A, US883414A
InventorsFrank M Merrill
Original AssigneeFrank M Merrill
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 883414 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

No. 883,414. PATENTED MAR. 31, 1908. v





PA DLOOK. urumrmn Human 13. 1901.

PATENTED MAR. a1, 1908.




To all whom it may concern:

Be it known that I, FRANK M. MERRILL, a citizen of the United States,.residing, at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Padlock, of which the following is a specification.

, Themain object of the present invention, is to f provide a lock wherein a large number of di erentiating locks can be made at relas tively small cost.

A further, object of the invention is to prevent, as far as possible, the possibility of picking the lock.

The invention is herein shown as applied to a padlock, but is capable of general use.

In the accompanying drawings:Figure 1 is a perspective of the lock. Fig. 2 is a sect'ional View of the lock. Fig. 3 is -a section on the line w--$" in Fig. 2. Fig. 4 is a side elevation of the tumbler barrel of the lock. Fig. 5 is a top view and Fig. 6 a bottom view thereof. Fig. 7 is a perspective of one form of tumbler of the lock. Figs. 8, 9 and 10 show other forms of the tumbler. Fig. 11 is a perspective of the key. Fig. 12 is a transverse section of the lock through one of the wards. Fig. 13 is a view of the lower end of the lock. Fi s. 14 to 16 are plans of different tumbler slides.- 7

, The lock comprises a case 1 and a staple'or U-shaped bolt 2, whose end portions slide in bores 3 in the case, one end portion being pressed by a spring 4 so as to tend to eject the free end of the bolt from the case. The case 1 is provided with a head or cap member 5 which screws onto a nipple 6 at the lower end of the lock case and is fastened in position by a screw 7 which is inserted throu h the bore 3 that receives the free end of t 1e bolt, this being done when such free end of the bolt is turned away from such bore.

When the free end of the bolt is inserted in the bore and pressed in, it is held in such position by spring pins or dogs 9 which slide in transverse bores 10 in the case and are pressed by springs 11 to force their ends into engage-'- ment with notches 12 in the respective end ortions of the bolt. To release these dogs iiom the bolt, a plate 13 is provided having a stem 14 whereby it is pivoted in the upper end of a barrel 15, said plate being "provided with two lpins 16 whose upper ends engage respective y with notches 17 in the respective dogs 9, and the lower ends of said pins on the plate extending in the path of motion. of

Specification of Letters Patent.

A umun filed lay 1a, 1907. Serial No. 373,512. I

Patented Iarch 31, 1908.

two lugs 18 on the barrel 15 aforesaid. The barrel s mounted in an axial chamber 19 of the case so as to turn freely therein, and its lower end engages with an internal annular flange 20 on the cap member 5 aforesaid, which thereby holds the barrel member in place. Below this annular flange the said cap member 5 is turned in to form a guard 21 Y which closes the lower end of the'lockcase except for a central opening 22 in said uard, said opening havin radial slots or note es 23 corresponding to t e key to be used in the lock. Around the barrel 15 the case 1 is formed with an enlarged c lindrical chamber v24, from the wall of whic extend inwardly two annular flanges 25 which are slotted or notched as at 26 to serve as wards for control of the tumblers in the barrel. In the resent case six such notches are shown in eac annular flange, the notches being in alinement in both flanges. The barrel 15 is formed to receive and guide a plurality of tumbler devices, for example, six, corresponding in numbeer to the num er of slots in the ward flanges,

a removable ca plate 27 being fastened on the lower end 0 the barrel to retain the tum-.

fin 30 which extends outwardly beyond the.

cylindrical portion 31 of the barrel in which the'tumbler slides, so as to enable s'aid fins to engage in the slots 26 of the ward flanges. These fins are of equal length, namely, a little less than the distance between the ward flanges and street variant longitudinal position, and by such variation is determined the differentiation in the different locks of the series. Normally, the said fins are at the lower end of their stroke and are in enga ement by some portion of the fin with t e corresponding slot in the lower ward flange. To unlock the lockit is necessary to move each of the tumblers upwardly a suflicient the lower ward flange without bringing the free ends into engagementwith the upper ward flange; Owing to the variant position of the fins on the'respective tumblers, it is requisite that the tumblers be raised to different extents in the unlocking operation, and this isiperformed by means of a key of the type shown in Fig. 11, said key having a plurality of fins 34 adapted to engage respectively with lugs 33 in the lower ends of the res ective tumblers, and said key fins being 0 variant length so as toraise all-of the? tumblers to the proper amount when the key is pushed in a definite distance. There being a pluralityof slots 35 in the barrel through which the key fins 34 can be inserted to engage the tumblers, it is desirable to rovide means forinsuring that"'tli e key wil .beinserted in the correct angular position, and for this purpose said key has a further series of fins 36, one of which, indicated at 37, is

longer than the others, the guard 21 on the cap member having radial slots 23to receive these fins, one of said radial slots indicated at 38 being longer than the others to receivethe elongated fin and thereby insure that the key is inserted in the proper position.

The fins 30 are cut away at each side and .at each end,.'preferably by chamfering as slip oif the wardbears no ascertainable relation tothe point of actual relation of the tumbler. from the ward, and it is therefore not possible for a person to pick the lock. The chamfering also has the ablvantage of facilitating entrance of the wards by the fins, so that in attempting to work any one tumbler to proper position, the other tumblers are liable to slip back into the wards. The variant positions of the chamfers on the fins are shown in Figs. 14 to 16, the chamfers being shown as of nearly but not quite the same length in Fig. 14, longer at one end in Fig. 15, and longer at the other end in Fig. 16. In any one look, tumbler slides with such variant chamfers will be used.

In operation of the lock with the proper key, the key, on being inserted in the lock, pushesback the tumblers until the fins on all the tumblers have been withdrawn from the first ward and occupy the free space between the two wards, without entering the second ward. The key can then be turned, rotating the tumbler barrel and, through the bler fins.

interm'ediadte member 13,. withdrawing the spring dogs from the bolt, allowingthe bolt to be projected by the spring. To withdraw the key it must be turned back to locking position, on account of the guard device, and

the plate 13 allows of the motion without disturbing the dogs, which are still held in un locking position by the engagement, of the end of one dog with the unnotched part of the shank of the bolt, .the other dog being .held open through the intermediate member 13, until the bolt. is ressed back to locking position, when the dogs enter the notches and the bolt. is automatically locked.

The slots 23 in the guard plate 21 and those in the end of the barrel fit the key fins closely, and the larger key fins are tapered at their ends as shown at 41, but the slots 26 said fins, so that as the key isushed in the fins will find their way into t 1e barrel and u ill center it, or bring it to absolutely correct angular position for starting. Then when the key pushes the tumbler slides along the barrel, the fins in the barrel work-through the slots in the 'wards without actual contact, said slots being a little wider than the tum- The distance between the two sets of ward devices or ward flanges is also somewhat grcater than the length of the fins, so that when the key is entered to proper distance, s determined by the long key fin 34 striking the end of the barrel, the tumbler fins will revolve free of the wards, so that there is no wear on the tumbler fins, either at the sides or ends, in the usual workingof the device. This long fin 34 is preferably chamfered as shown at 41. I

While chamfering of the ends of the tumbler slide fins is advantageous, said fins may be cutaway as shown at 42 in Figs. 8, 9 and .in the wards are somewhat wider than the 10, forming more or less square shoulders at one or both ends, the. differentiation of the position of these shoulders giving a protectwe or non-pickable quality.

What I claim is 1. A look comprising a case having a cham ber with two slotted ward flanges, a barrel rotatable in said chamber, a plurality of tumbler slides longitudinally movable in said bar rel and having fins to enter the'ward slots, the fins being of a length nearly equal to the distance between the ward flanges and being in different longitudinal positions on the different tumblers, and a guard member closing the end of the case and having slots, the wards having slots which are slightly wider than said slots in the guard, for the purpose set forth.

2. A look comprising a case having a chamber with two slotted ward flanges, a barrel, rotatable in said chamber, a plurality of tumbler slides longitudinally movable in said barrel and having fins to enter the ward slots, the fins being of a length nearly equal to the distance between the ward flanges and bein in different longitudinal positions on the di ferent tumblers, and a guard member closing the end of the case and having slots, one'of said slots'being longer than the others.

3. I Alock comprising a case having achamwber with two slotted ward flanges, a barrel rotatable in said chamber, a plurality of tumbler slides longitudinally movable in said barrel, and having fins to enter the ward slots, said fins being chamfered near each end, the longitudinal length of the chamfered portions being different in the different tumbler slides. 5. In a lock, the combination of the bolt, a spring for moving the bolt to unlocking positlon, dogs for holding the bolt in locked position, a rotatable barrel provided with key controlled means, a plate having pro'ections engaging the dog and the barrel, said plate beingada ted to turn freely with res ect to both the 0g and the barrel through a imited angle, and means for preventing withdrawal of the key except when the barrel is in locking position.

6. In a padlock, a case having two longitudinal bores,'a U shaped bolt movable in said bores and having two notches, said case having two transverse bores drilled from op-- posite sides of the case, each transverse bore intersecting a longitudinal bore, a spring for moving the bolt to unlocked position, spring actuated dogs in the transverse bores to engage the notches in the bolt, and key congrcilled means for releasing said dogs from the 7. In a lock, the combination with the case having two longitudinal bores, a U shaped bolt movable in said bores and adapted to disengage from one of the bores, key 0 erated' means within the case, a' cap screwe on the end of the case and forming a continuation of the body of the case, said case having a deep socket, the ca being drilled and threaded in alinement with the socket, and a screw bolt in the bottom of the socket threaded in the ca In a lock, Wards, and tumblers formed with releasing edges having inclined faces, the angle of inclination and length of inclination being variant in the respective tumblers, whereby apparent release of the tumblers from the wards before actual position for release, is caused in attem ting to pick the lock.

' In testimony whereo I have hereunto set my hand at Los Angeles, California, this 6th day of May 1907.

FRANK M. MERRILL. Witnesses:


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2678554 *Jun 30, 1952May 18, 1954Luther PalmerPadlock
US4838051 *Apr 27, 1988Jun 13, 1989Yang Yaw MeinPadlock and key assembly with transversely movable tumbler units and vertically movable tumbler units
US5587702 *Nov 12, 1993Dec 24, 1996Chadfield; Garth R.Padlock with tamper alarm
US5655391 *Feb 23, 1995Aug 12, 1997R.P.L. Industries Pty. Ltd.Padlocks
Cooperative ClassificationE05B67/24