US2942451A - Latch lock - Google Patents

Description

June 28, 1960 a. WINDMASSINGER 2,942,451

LATCH LOCK Filed Sept. 11, 1957 4 Sheets-Sheet 1 A TI'OKIVZY I G. WINDMASSINGER 2,942,451

June 28, 1960 LATCH LOCK Filed Sept. 11, 1957 4 Sheets-Sheet 2 INVENTOR.

GEORGE WINDMASSINGER BY June 28, 1960 s. WINDMASSINGER 2,942,451

LATCH LOCK 4 Sheets-Sheet 3 Filed Sept. 11, 1957 E W I;

16 no I02 l0. "8 3 GEORGE WINDMASSINER June 28, 1960 G. WINDMASSINGER 2,942,451

LATCH LOCK 4 Sheets-Sheet 4 Filed Sept. 11, 1957 INVENTOR.

GEORGE WIN DMASSINGER A broken away, of the lock mechanism;

United a s Pa n LATCH LocK George Windmassinger, Feasterville, Pa., assignor to George B. Henne & Co., Inc., Philadelphia, Pa., a corporation of Pennsylvania Filed Sept. 11, 1957, Ser. No. 683,332.

. 6 Claims. -(Cl. 70-150) This invention relates to a latch lock mechanism having general utility but especially well adapted for use in ofiicebuildings.

In otfice buildings it is desirable that the doors be capable of opening freely from the inside or outside during working hours, but after working hours it is desirable that the. doors be restricted .by a lock mechanism wherein those remaining invthe building can easily open the doors to leave, while those wishing to return after working hours can do so only with a key.

The primary object ofthe invention is to provide a lock mechanism capable of performing the aforementioned functions. The mechanism is a latch lock operable by a lever handle from one side and a key from the other. The construction and arrangement of parts are such that when the latch bolt is retracted by key operation, a means is automatically actuated holding the bolt in a fixed fully retracted position. In this position the, lever handle is incapable of afiecting the lock mechanism so that the door is freely movable from inside and outside the door. -This-is the position of the lock during ofiice hours. On the other hand, when the key Figure '7 is a reverse elevational view of the main,

latch bolt, auxiliary bolt and yoke;

Figure 8 is a view similar to Figure 2 showing the latch bolt in a position as retracted by the key, the

auxiliary latch being broken away for clarity;

Figure 9 is a fragmentary view similar to Figure 7 with latch bolt in extended or door locking position and about to be retractedby key operation;

Figure 10 is a fragmentary view similar to Figure 9 showing the position of the latch bolt as completely re-- Figure 12 is a view similar to Figure 8 showing posiv tion of latch bolt as retracted by lever handle;

is operated to release the latch bolt to the door locking open the door from the inside and automatically lock it I when the handle is-released. From the outsideYonly key operation can open the door. This is the after' ofiice hours position, of the lock. V Another object of the invention is to provide, a lock mechanism of the character described which is, of such construction and arrangement of parts as to permit it readily to be installed in relatively narrow metallic door frame extrusions. v

A further object of the invention is to provide a lock mechanism of the character described in association with an auxiliary lock which prevents the main latch bolt from being retracted by prying implements applied to the bolt. 7

And yet another object of the invention is to provide. a lock mechanism which can be manufactured of standard parts, which is relatively simple to assemble, relatively easy to install and relatively easy to repair. 7

These and other objects of the invention will become more apparent as the following description proceeds in conjunction with the accompanying drawings, wherein:

Figure 1 is a group perspective view, some parts being Figure 2 is an elevational view looking towards the front of the lock with the rear, wall broken away and handle omitted;

Figure 3 is an end left n s e'lr p, v

Figure 4*is af'section taken on the. line -4 of Figure 2;

Figure 5 is a section taken onthe line 5--5 of Figure 2;

Figure 6 is a section taken on the line 6--6 of Figure 5;

elevational :view looking to the- Figure 13 is an elevational'view looking to the rear on the cover plate carrying the lever handle-cam; and

Figure 14 is afragmentary view similar-to Figure 12 I with parts broken away to better illustrate the relative position-of the operating elements.

Specific reference is now made to the drawings where-- in similar reference characters. are used for corresponding elements throughout.

The present lock mechanism walls 18-and 20. Secured by appropriate screws to the side wall 12 is a face plate 22, there being aligned; openings 24 and 26 in the side wall and face plate through which the main and auxiliary latch bolts'are made to' extend. The housing containing the lock mechanism is adapted for ready installation into theframe of a door and accordingly, the main latch bolt is movableinto I and outof engagement with a keeper which is normally another opening 28 that is provided in the door jamb 30, there being no opening orkeeper for'the auxiliary latch bolt. x

Threadedinto'a suitable opening in the front wil 141's aconventional-pintumbler lock which contains a barrel 32 in which is rotatably mounted a plug- 34- operable by a key 36.. -Mounted on the end' of the plug which is disposed within the housing is an; arm 38. The proper adjusted position of-the-barrel 32'011 thefront wall 14 is maintained by an appropriate set screw 40 V which'enters an axial groove on the side of'the barrel,-

as shown'clearly'in Figure 3.

A latch bolt actuating plate 42 its upper end carriesa pin 44 and at its lowerend is provided with a curved portion 46. The pin 44 extends perpendicularly throughthe plane of the plate 42 and, includes reduced terminal portions 48 which are jours naled for rotation in suitable apertures 50fthat are providedin the front and rear walls 14 and 16. 1 Thus the plate 42 is mounted in such a way that its lower curved portion 46 is movable towards and-awayfrom the side plate 1 2 about 'the pivot pin 44. Adjacent its lower curved end 46, the plate 42 also carries apin 51 which extends perpendicularly'therethrough, said pin having a portion 52 facing the front wall and a portion 54 facing the rear. wall. Between thepivot pin '44 and the pin 51 the plate 42 also carries a "perpendicularly extending pin 56v which faces-the rear wall 16.. .A' spring 58 is wound about the pivotpin .44 and has a terminal portion 60 which. bears against-the'upperfwall- 18. and another terminal portion 62 which bears, against the pin 56,}thej spring acting ,to'bias thelowercurved portion 46 of the plate towards the sidewall 12. lThe plate 42 is so mounted in. the housing that roation of the plug 34 by 3 the key 36 in a clockwisedirectionwillmove the plug arm' 38 into positionlto bear against'the portion 52 of the'pin 51 and continued movementof the key will pull 2,942,451 Patented June28, 1960 is generally indicated at; I 10and is contained in a housing comprising a side wall' 12, a' front wall 14, a rear wall 16 and top and bottom is provided which, at} v the lower end of the plate 42 away from the side wall 12.

The main latch bolt is indicated at 64 and is a substantially rectangular block having the conventional forward arcuate portion 66. To the rear of the arcuate portion the bolt consists of a pair of spaced plates 68 and 70 each including a slot containing a longitudinal portion 72 and a lateral portion 74. Threaded into a pair of appropriate aligned apertures in the plates 68 and 70 of the latch bolt is a screw 76, the head of which is adapted to strike the side wall 12 and serve as a stop to limit the outward or extended movement of the latch bolt 64, there being a bushing 78 which is interposed between the plates 68 and 70 for receiving the stop screw 76. At another predetermined location, another pair of aligned apertures is provided in the 'plates68 and 70 of the latch bolt for receivinga-further screw 80, there being a bushing 82 about said screw which is interposed between the plates 68 and 70 of the latch bolt.

Secured to the frontwall 14 adjacent its lower end is a square post 84 with a collar :86 thereabout and a pin '88 extending diametrically through the collar and the post. The latch bolt 64 is provided with a recess 90-forreceiving-one end of a coil spring 92 which extends longitudinally-of; the latch bolt, the other end of the spring receiving the pin 88 and pressingagainst the collar 86 on the ;post 84. The spring 92 is biased to urge the latch bolt in an extended position through the opening 24 in the face plate and therefore towards the locked position, In the sliding movement of the latch bolt itwill be observed that the plates 68 and 70 of the latch bolt-receive the collar 86 between them and the square post 84 -slides-in'the longitudinal portion 72 of the latch bolt slots,

Mounted for vertical-movement on the front wall 14 is a substantially rectangular plate or slide 94. The upper surface of said slide is curved as at 96 and the upper cornerof the slide remote from the side wall 12 is cut off or downwardly inclined as at 98. The slide also contains-'a slot mil -opening through its lower edge and of-widthsufiicient to clear the square post 84, the thickness oftheslide beingsuch that it under-rides the collar 86 on the square post 84. The lower corner of the'slide-rem'ote from the-side wall -12 includes'an angu lated, open-ended slot 102.- Thelower edgeof'the slide 94 includes a groove 104 into' which fitsone portionof ;a. spring 106-'whichis-'wound about a hollow post 108 that is mounted on the front walli14,- thespring 106 normally urging the slide upwardly so that its upper curved -surface96 engages the portion 52 of the pin 51 carried bythe plate 42'. -At-'a predeterininedilbcation on the side of the slot 100 towards-fireside wall 12, the

slide-carries an upstanding pinf1'10;

-A locking levenb'ar; 112; is providedwhich is pivoted intermediate its ends; by a pin- 114' to the front wall 14 adjacent the-hollow postl08i Theupper-portionofthclocking lever112 is curved'as at-116 arid: the lower end urges the hook end of the'lock'ing lever towards the slide v94.

The rear wall 16 includes adisk 'l26 in which is rotatably mounteda bearing-128 with-asquare opening 130 for receiving the square shaft 1320f a-lever handle-134.-

Mounted Olltl'l bearing for rotation therewith is .a cam member 136 having a portion 138ithat .is adapted to bear against the pin 56 of theplatej 42. Upon rotationlof the handle 134' ina clockwise. direction, the portion 138 of the cam 136 will bear against .the.pin.56. and pivot the lower end 46 of the plate 42 awayffrorrt the side wall 12. The, rear wall 16 is .furthenprovided with' a block.

140. in which isthreaded a set screw 142, thesarnebeing so set that the earn 136 strikes the set screw 142 before the latch bolt is completely retracted. The reverse or counter-clockwise rotation of the lever handle 134 is limited by the fact that the portion 138 of the cam 136 strikes another stop 144 which is carried by the rear wall 16 opposite the set screw 142. A spring 146 is provided which normally urges "the portion 138 of the cam 136 away from the set. screw 142.

At this point the operation of the lock will be described first in connection with key actuation and then in connection with handle actuation. Regarding key actuation, it will be seen from Figure 9 that whenthe latch bolt 64 l is extended into thedoor latching position, the portion 52 of the pin 51 of the plate 42 bears against the upper curved surface 96 of the slide 94 urging the latter downwardly against action of the spring 106. In this lowered position the slide pin 110 is positioned in front of the block 84 and therefore is in alignment with the longitudinalportion 72 of the latch bolt 's'lot. Also in this lowered position of the slide, the longitudinal edge portion 148 which faces away from the side wall 12 bears against the hook 118 of thfe locking lever 112 so that the hook 118 is not engaged in the slide slot 102,. as shown clearly in Figur'e 9. Rotation ofthe key in a clockwise direction as indicated by the arrow in Figure 9 will cause the arm 38 to bear against the portion 52 of the pin 51 of theplate 42. Continued rotation of the key in the clockwise direction will urge the plate 42 away from the side wall 12 and in so doing the curved portion 46 at the lower end of the plate 42 will pull on the bearing 82 of the latch bolt screw 88 thereby retracting the latch bolt 64 against action of the spring 92. As the latch bolt is retracted the portion 52 of the pin 51 rides on the upper curved surface 96 of the slide 94 and keeps. the slide in the downward position as previously described hereinab'ove and as shown in Figure 9. When the latch bolt is completely retracted within the aperture 24 so that its outer edgeyclears the surface of the face plate 22, as shown in Figures 8 and 10, the portion 52 of the pin 51 of the plate 42 has assumed a position at'the cut-elf corner portion 98 of the slide 94, as shown in Figure 10. When this occurs the slide 94 is' moved upwardlyby its spring 106 sothat the slide plu 110 engages in the lateral portion 74 of the latch bolt slot. At the -same time the slide 94 moves upwardly to a position where the hook .118 of the locking lever 112 engages in the slot 102 at the lower corner of the slide 94; asl'sh'own in Figure 10. Thus when the latch bolt 64 iscompletely retracted by the key the. latchholt is' fi xedly' retained in the completelyretracted position.

The latch bolt is released by) key operation in the following manner, as shownin Figure 11. When the key is rotated in a counter-clockwise direction as shown by the arrow in Figure 11, the rotatable plug'arm 38 strikes the curved portion 116 ofthe lockinglever 1 12 thereby rocking the lever about its pivot 114 and urging the hook 118 out of engagement with the slide slot 102.

When this occurs the inner surface of the curved portion 116 of the locking lever presses against the portion 52of the pin 51 of the plate 42 so that it clears the cut-off corner 98 of the slide, whereupon the spring 92 urges the latch. bolt 64 into"the latching position and the spring 58 acting on the plate 42 urges the curved portion 46 of saidplate'towards the side wall 12.

Regarding the operation of the lock by the lever handle 134, when the latch bolt is'in the extended or r latching position. and the lever "handle is rotated in 'a clockwise direction when looking on the rear wall 16. the portion 138 of the earn 136 bears against the pin 56 of. the plate 42 thereby pivoting the latter'so that its lower curved portion 46 acts upon the latch bolt screw 80. to.;retract the latch bolt 64. This retraction takes placeto thepoint where the portion 138 of the lever handle: cam. l36strikes the stop 142; as shown in a handle as it is by operation of the key.

Figure 132;, This position .is such thatfgthdportion-52 of the pin 51 of the plate 42 still rides uponthe uppe'r' curved surface 96 (if-the slide-Maud has not reached the cut-ofi corner 98. As a result, after. complete rotation ofthe lever handle until its cam strikes the set screw stop 142, the slide 94 still remains in the position shown in Figures 9 and '14 so that the latch bolt is not retained in a fixed retracted position by operation of the lever To improve the security of the lock so that it will resist opening of the main latch bolt by a prying implement applied thereto, an auxiliary lock mechanism is combined with the aforementioned elements. Said auxiliary lock mechanism comprises a substantially. U-shaped yoke 150 having upper and lower legs '152 and 154, a depending-pivot pin 156 adjacent its lowercorner, an inclined cam surface 158 on the leg 152, a shoulder 160 on theinner surface of the lower leg 152 and, an aperture 162 in iaportion of the yoke adjacent its uppercorner. Said-yoke 150 is positioned in the casi'n'gso that its pivot'pin 156 is journaled in the hollow post 108 whereby the upper and lower legs 152 and 154 frame the latch bolt 64, there being a central lug 164 which is carried by. the web of the yoke that is adapted to enter the longitudinal portion 72 of thelatch bolt 64, as shown more clearly in Figures 7, 8 and 12. One arm 166 of the slide spring 106 extends through the aperture 162 of the yoke and thereby biases'the yoke upwardly about its pivot pin'156 so that the shoulder 160 is urged into the space between the upperand lower plates 68 and '70 of the latch bolt adjacent the latch bolt stop screw 76, as shown more clearly in dotted lines in FiguresZand 7.

The auxiliary lock mechanism also includesan auxiliary latch bolt 168 which is adapted to move in and out of the aligned openings 26 in the side wall 12, and face plate. 22. The auxiliary bolt 168 includes a plate 170 having an elongated slot 172 for receiving the head of the main latch bolt screw 80 and an inner curved shoulder 174 forming a, groove ,which receives the portion 54 of the pin 51 of the'plate 42. The end'of the plate 170 of the auxiliary latch bolt 168-which faces away from the side wall 12 contains a groove which seats a coil spring 176 whose other end is seatedin the groove of an abutment 178 that is carried by the rear wall 16 of the housing. 1

The spring 176 normally urges the auxiliary latch bolt 168 outwardly through the opening 26, and when this occurs a portion of the shoulder 174 of the auxiliary latch bears against the portion 54 of the pin 51 of the plate 42. This portion 54 of the pin in turn presses againstthe leg 152 of the yoke at a point beyond the inclined surface 158, thereby rocking the yoke 150 downwardly about its pivot pin156 so that the shoulder 160 of the lower leg 154 of the yoke is moved out of the space between the plates 68 and 70 .of the main latch bolt 64,,as shown more clearly in Figure 12. However, when the auxiliary latch bolt 168 is itself retracted while the main latch bolt 64 is in the extended or latching position (and this occurs because there is nokeeper opening in the door jamb for the auxiliary latch bolt), then the portion 54 of the pin 51 of the plate 42 is caused to be positioned above the inclined surface 158 of the upper leg 152 of the yoke 150, whereupon the yoke rocks upwardly and the shoulder 160 on the lower leg 154 of the yoke enters the space between the upper and lower plates 68 and 70 of the main latch bolt 64. I

Thus when the main latch bolt is,extended but the auxiliary latch bolt is retracted, a prying implement applied to the main latch bolt cannot retract the same since it is obstructed by the shoulder 160 of the yoke. However, the main latch bolt can be retracted eitherby the portion 46 .bears against the main latch b'olt' screw 86.

At the sameftime, whilethe portion 52 of the pin 51 of the plate 42 rides upon the upper curved surface 96 of the slide 94, the other portion 54 of the pin 51 is caused to L bear against the leg 152 of the yoke and rock it, whereupon the shoulder of the yoke moves out of the space between the plates 68 and 70 of the'main'latch bolt so that the main latch bolt is free to be retracted.

While 'a preferred embodiment .of the invention. has

been shown and described hereinabove, minor variations may be made by skilled artisans in the construction and arrangement of parts without departing from the spirit of the invention and the scope of the appended claims.

.Iclaiin:

1. A latch lock mechanism comprising a substantially rectangular housing having a side wall and front and rear walls; a latch bolt, slidable through'an opening provided in said side wall; said latch boltincluding a slot having a longitudinal and alate'ral portion, spring means normal ly urging said bolt through the. opening towardsthe locked position,'a plate pivoted to'said front wall formovement towards and away from said side wall, a first pin carried by said latch bolt, a curved member at one end of said plate bearing on said pin, a substantially rectangular slide beneath said latchbolt and movable vertically, said slide above its slot when the latch bolt is through the opening in the side wall and in the locked position and said slide pin being in position to enter 'the longitudinal portion of said latch bolt slot, a barrel mounted in the fnontwall of said housing, akey-operated plug rotatable in said barrel, said plug including an arm thereon extending beyond the barrel and'into the housing whereby when the key-operated plug is -rotated'clockwise, said arm bears on said second pin to pull saidplate-away from said side wall,

the curved member of said plate pulling 1011 said first'latch' bolt pin toretract the latter, said second pin riding against the upper curved surface of said slide until saidlatch bolt is'fully retracted whereupon said second pin reachesth'e cut-off corner of said slide allowing the slide spring means to push the'slide upwardly'until the slide slot is'engaged by the'locking lever hook and theslide pin is engaged in the lateral portion of the latch bolt slot to retain the latch bolt in a fixed retracted position, and whereby upon counterclockwise rotation of the plug, the plug arm'bear's against the upper curved portion of the locking lever urging saidcurved portion against said second plate pin and also rocking said locking lever until its hook is released from the slide slot, whereupon the latch bolt moves into' the lockedposition through the opening in the side walll 2. The combination of claim 1 and a cam rotatably mounted on said rear wall, a lever handle ioperatively connected to said cam and a stop carried by said rear wall at a predetermined position from the cam, said plate ineluding a third pin, whereby operation of the'lever handle clockwise will. cause the cam'to engage said third pla te pin, move the latter and retract'thelatch bolt, but said cam will strike said stop before the locking lever hook can engage the slide slot so that the latch bolt cannot be retracte'd to a fixed position by operation of the lever handle nor can the lever handle affect the latch bolt after the latter has been fully retracted to a fixed position by the key operated plug. 7

3. The combination of claim 2 and an auxiliary lock mechanism which prevents prying retraction of said latch bolt.

7 4. Thecombination of claim 3 wherein said auxiliary lock mechanism comprisesra substantially U-shaped yoke pivoted at: oneof its corners to theifron't' wall, one'i leg: of

which has a shoulder and the: other leglofwhi'chh'asian inclined surface, spring means'biasirig, said yoke so that the shoulder of :said one leg obstructs 'move'rnent of said latch bolt whilesaid incIinedsurface' engages said second plate pin, and aniauxiliary bolt adapted'tdpassthrough an additional opening'in said sidewall, sai'd auxiliary bolt having an extension withian arcuate recess receiving said? the extended position through its opening in said side wall, the walls .ofsaidarcuate recess force 'said 'se'cond' plate pin against said other leg of said yoke so that the latter pivots andzmoves the shoulder of said one yoke leg out of obstruction with said latch bolt 'and the latter is fully retractable'whereas when said auxiliary bolt is itself" retracted,lsaid second plate'pin engages said inclined-surface of said other yoke leg and saidshoulder on said'o'ne yoke leg obstructs said latch'bolt. 4

5. A latch lock mechanism" comprising a housin'g having a side, front and rear Wall, a latch bolt slid'ablej through an opening provided inthe side wall, spring means normally'urging the latch bolt through-theopen' ing towards anextended position, latch bolt retractingmeans, a key-operated plug rotatably mounted on the front wall, said plug including'an arm operative upon said latch bolt-retracting means, means releasably'retaining said latch bolt in a fixed position-when the-latter isslide and'riding in the longitudinal portion of said latch bolt during extension and retraction thereof, means'permitting said slidepin to' enter s'aidlateral portion of said latch bolt slotwhen said latch bolt isfully retracted and means releasably locking" said slide withsaid slide pin in the lateral portion of said latch bolt slot, said slide including an upper curved surface against which said plate pin bearsto push said slide down with said slide pin inthelongitudinalportion o'fsaid latch'bolt slot, said" means permitting said slide pin to" enter said lat'eral portion of the latch boltslot including a cut-oiiportion-in the slide'downwardly inclined from one end df-said upper curvedsurface, whereby when said plate'pinreaches said cut ofi portion at full retraction of said latch bolt, the slide is free to be urged upwardly by its spring means whereupon said slide pin enters said lateral portion of said latch bolt slot, said means'releas'ably locking said slide pin in the lateral portion of said latch bolt slot including a lever pivoted intermediate its ends to said front wall, a hook at the lower'endof said lever and a curved portion at its upper'end and spring means urging said hook towards said slide, said slide having a slot towards its lower end, said hook bearing against an edge of said slide above said slide slot when theslide is down and said slide'pin is in the' longitudinal portion of said latch bolt slot, said hook engaging said slide slot when the slide moves upwardly upon complete retraction or said latch bolt, said hook being disengaged from said slide slot upon reverse rotation' of plu'g whereby said -plugarm 10 second plate pin whereby when saidauxiliary bolt is-in" front wall, said plug including an -arm operative upon said latch bolt retractingmeans-meansreleasably retaining. said latch bolt in afiXed positionwhen the latter is fully retracted; a lever handle rotatably mounted on the rear wa1l,:a cam 'carried by the handle and operative'onthelatch boltaretracting means, and astop carriedby the rear nrallzat api'edetermined-locationen gaggabl' t 7 Cam Position where the-means releasably retain ingthe' latch bolt in 2a 'fiire'd position isinoperative, said lat'ch bolt retracting means-"including a plate pivoted at one ofits ends between the front arid rear walls, the-other end of said platebearingmpona portion of said latch-bolt,-

said plate including-a pin adjacent said other end engagethe longitudinal portion ofsaidlatch bolt during exterision and retraction thereof, meanspermittingsaid slide pin to enter said lateral portion of saidlatch bolt slot when said latchboltisfullyretracted and means-releas ably locking saidislide' with said 'slide pin inthe lateral upper curved'surface-against which saidplate pin b'ears to'push said slide down with said-slide pinin the longi-' tudinal portion of said latchbolt slot; said means per mitting said" slide'pin to enter said lateral portion of the latch bolt slot-including a" cut-ofi portion in theslide downwardly inclined-from one' endof said upper'cur ved surface, whereby when-said-plate pin'reaches-said-cut-ofiportion at full retractionof saidlatch bolt, the slide is free to be u'rged upwardly by its spring means whereuponsaid slide'pin enters said lateral portion of said' latch-bolt slot, said means-- releasably locking said slide pin' in the lateralportion of said latch bolt slotincluding a lever pivoted intermediate its ends to said front wall,-a hook at the lower end of said lever and a curvedportion at its upper-end andsprin'g means urging. said hook towards said'slide, .said slide having 'a' slot towards its lo'wer end;

said hook-bearing against anedge'of saidslide above said slide"slot:when'theslide'is down and said-slide pin is'in the longitudinal portion of-s'aid latch boltslot,- s'aid hookenga'ging said=slide slot when the slide moves upwardly npon.complete'-.retraction ofsaid latch bolt, said hook being 'disengaged from-said-slide'slot uponreverse rotation-of plug whereby said plug arm bears against the upper curved-portion of-saidleverto trip the latter.

References-Cited in'the fileof this'patent FOREIGN PATENTS 463:6 05 Great Eritain Apr; 2, i937

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