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Publication numberUS3600021 A
Publication typeGrant
Publication dateAug 17, 1971
Filing dateSep 15, 1969
Priority dateSep 15, 1969
Publication numberUS 3600021 A, US 3600021A, US-A-3600021, US3600021 A, US3600021A
InventorsHawkins Paul Maddison
Original AssigneeMinnesota Mining & Mfg
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lock structure
US 3600021 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent Inventor Paul Maddison Hawkins Afton, Minn. Appl. No. 858,048 Filed Sept. 15, 1969 Patented Aug. 17, 1971 Assignee Minnesota Mining and Manufacturing Company St. Paul, Minn.

LOCK STRUCTURE 7 Claims, 4 Drawing Figs.

U.S. C1. 292/167, 292/335, 292/341 17 Int. Cl E05b 15/02. E05b 63/20, 1505c 1/12 Field 01 Search ..292/341.17,

336.5,254,153,341.16,335,167,1,163,164, 169.13,l6).l8;70l15(),157

[56] References Cited UNITED STATES PATENTS 1,262,435 4/1918 292/341.16 1,302,873 5/1919 292/335 1,330,693 2/1920 292/335 2,010,237 8/1935 292/153 X 2,575,465 11/1951 292/34l.l7X 3,112,944 12/1963 292/153X Primary Examiner-Jan A. Calvert Assistant Examiner Edward J. McCarthy Attorney-Kinney, Alexander, Sell, Steldt & Delahunt ABSTRACT: An improved latchbolt structure for a selfreleasing and projecting lock structure and lock means in the strike for securing the latchbolt in projected position.

LOCK STRUCTURE This invention relates to an improved latchbolt and in one aspect to an improved latchbolt and lock combination whereby the self-projectinglatchbolt of a door lock structure may be locked in place upon closing the door to prevent the unlatching of the door from the inside after breaking a window in the door perhaps to gain access to the inside knob. A

Many of the lock structures presently available for door hardware on houses or apartment doors are formed such that the outer knob can receive the key for releasing the latchbolt upon the prior operation of a pushbutton or turn button which actuates a locking mechanism which functions to lock the outer spindle and knob against rotation thereby preventing the opening of the door from the outside except with a key. This type of lock structure is commonly referred to as a bored lock and is typical of that illustrated in the Schlage US. Pat. No. 2,038,907. With this type of structure in a door however it is possible to gain entrance through the door upon access of the latchbolt assembly is first inserted through an opening 16 from inside knob which is freely rotatable whether the pushbutton is actuated or not. It is therefore an advantage of the present invention that the inside of a door having a lock structure of the type commercially available may be readily adapted for preventing entry even after access of the interior knob is gained.

It is an object of the present invention to provide an improved latchbolt for use on existing door hardware and on new hardware.

An advantage of the invention is to provide a spring-actuated latch or dead bolt which projects into the strike .plate about, 100 percent further than with existing hardware to increase the effect of the latchbolt.

' The present invention also provides a latch structure which, upon projection of the latchbolt into latching position, will lock the same against retraction upon operation of the inside or outside knob.

,The lock structure of the present invention prevents one from gaining access to the apartment by merely picking a key lock in the outer knot, breaking the window and gaining access to the interior knob or by otherwise compromising the door lock structure. V

The present invention comprises an improved latchbolt with an increased throw and one which will automatically be released to project into the strike upon a boltlocking arm hitting the strike plate and releasing the latchbolt. The invention further comprises a presettable auxiliary lock for the door jamb to lock a projecting door latchbolt in position. The jamb lock for the latchbolt comprises a bolt latch which is cam operated by the bolt of a standard push lock.

The above and further advantages of the present invention will be more fully understood after reading the following detailed description which refers to the accompanying drawing wherein:

FIG. 1 is a horizontal sectional view through a portion of the door and jamb illustrating a lock, partially in section, constructed in accordance with the present invention;

FIG. 2 is a vertical sectional view taken generally along the line 2-2 ofFlG. l; i I

FIG. 3 is an exploded perspective view of the parts forming the latchbolt of the present invention; and

FIG. 4 is an exploded perspective view of the lock structure on the strike plate formed in accordance with the present invention and utilized to lock the latchbolt in place in the strike plate.

Referring now to the drawing there is illustrated the lock structure of the present invention in position on a door 6 in which is inserted a lock-actuating unit generally designated 7 and cooperating with a strike 8 formed in a door jamb 9 having a piece of molding 10. The lock-actuating unit 7 consists of a central housing at opposite ends of which extend hub members to which the exterior knob 11 and interior knob 12 are supported. Escutcheons l4 and 15 position the lock-actuating theedge of the door. The lock-actuating unit is inserted from opposite sides of the door in opening 17 and is assembld to interlock the bolt retracting mechanism with the bolt assembly as is well known in the art. i

The bolt-retracting mechanism of the lock-actuating unit 7 is supported by the door housing structureand is provided with a retractor having a pair of vertically spaced fingers 20 and 21. The fingers 20 and 21 are provided to engage a pair of lugs 22 on a latch bolt retractor bar 24. The latchbolt retractor bar 24 reciprocates within a cylindrical housing 25 secured to the back of a faceplate 26 of the latchbolt assembly normally inset in the edge of the door and secured thereto by screws 27 and 28 as shown in the drawing. A latchbolt 30 is telescopically received within the housing 25 and has a longitudinal central bore 31. The bore 31 receives the latchbolt-retracting bar 24 and contains a c'ompressionspring 32 which tends to drive the latchbolt 30 off the latchbolt-retracting bar 24. A lever 34 retains the bolt 30 and bar 24 and affords relative movement between the bar 24 and the latchbolt 30. The lever 34 is pivotally mounted at one end by a pin 35 to a pair of upstanding ears on the cylindrical housing 25. The lever 34 extends through the housing 25 and through'a diametrical slot 37 in the latch bolt 30 to penetrate the bar 24 through an opening 36. The enlarged slotted opening 37 in the central portion of the latchbolt 30 does not extend entirely through the bolt 30 and terminates at a wall portion in the lower part of the bolt, which wall portion is formed with an opening 39. The extended end of the lever 34 penetrates the bolt opening 39 and a slot 40 in the lower side of the housing 25. Thus the lever 34 can swing an are about the pin 35 through the slot 40 in the housing. As noted in FIG. Z'retraction of the bar 24 by the fingers 20 and 21 on the lugs 22 causes the lever 34 to pivot or swing toward the retracting mechanism of lock-actuating unit 7. The lower extended end of the lever 34 engages the inner edge of the opening 39 causing the bolt 30 to be retracted compressing the spring 32 in the bore 31 of the bolt.

Upon retraction of the bolt 30 into the housing 25 a releasable bolt latch 42 engages a shoulder adjacent the free end of the bolt. The latch 42 has a hook 43 on the outer free end thereof biased by a spring 44 into engagement with a shoulder 45 formed on the side of the bolt 30. The bar 42 is guided in an axially extending slot '46 on the side of the bolt 30 and the shoulder 45 is positioned with respect to the end of the bolt and slot such that upon swinging movement of the door 6 toward the closed position shown in FIG. 1 the free end of the bolt 30 first strikes a strike plate 47 of the strike 8 and is forced into the housing 25 and then the extended end of latch 42 catches thestrike plate 47 causing the same to move away from the bolt 30 and out of engagement with the shoulder 45. Release of the bar 42 permits the spring 32 to drive the bolt 30 away from the bar 24 and through an opening 49 in the strike plate 47.

The strikes is fitted on the jamb and comprises the strike plate 47 which is recessed into the face of the door jamb. Secured to the backface of the stride plate 47 and surrounding the opening 49 is a frame 53 which will receive the extended latchbolt 30 and will support the bolt-locking mechanism as hereinafter described.

The strike frame 53 is received in an enlarged oblong opening 55 formed in the jamb'9. Formed transversely to the opening 55 is a cylindrical opening 56 to receive a standard push lock 58. The standard push lock 58 comprises a sleeve 59 mounted for attachment in a circular side opening 60 on the frame 53 by a set screw 61 to secure the push lock in position. Within the cylinder 59 is a sliding pin tumbler plug 62 formed with a keyway 63 to receive the key for unlocking a pawl on the plug 62 and allowing the same to slide axially in the cylinder 59. A pin or pawl (not shown) carried by the plug 62 is biased into an opening 64 in the cylinder 59 to retain the plug 62 in a locked position after more inward sliding movement. The pawl is released from opening 64 by inserting the proper key in keyway 63 and rotating the same. Secured to the end of the plug 62 is a bolt 65 which extends generally axially thereof and which generally affords the locking action.

In the illustrated embodiment the bolt 65 is cut away to form a recessed cam surface 70 which cooperates with a spring-biased pawl 66. The pawl 66 is pivotally mounted in the frame 53 for movement about the axis of a pin 67 secured through the frame 53. A spring 68 urges the pawl 66 into a latching position with respect to the end of the latch bolt 30 to place the hook end of the pawl over a transverse latching surface 69 formed by a recess in the free extended end of bolt 30. The pawl 66 is moved to the latching position under the bias of the spring 68 and is moved out of latching position by action of a cam follower surface 72 formed on the pawl 66 and engaged by the recessed cam surface 70 on the bolt 65. Reciprocal movement of the bolt 65 and rotation thereof causes the cam follower 72 of the pawl 66 to move the pawl 66 to the unlatching, raised, position. In this position operation of the inside handle 12 will retract the bolt 30 or unlocking of the outside handle will permit retraction of the bolt 30. The pawl 66 is retained in unlocked position when bolt 65 and plug 62 are retracted.

The push lock 58 may be moved from the unlocked position shown in FIG. 1 to the locked position as shown in dotted lines in FIG. 2 by moving the same axially of the sleeve 59. Thus the recessed cam portion 70 of the bolt 65 will be beneath the cam follower 72 allowing the spring 68 to urge the pawl downward. If the door is closed and the latchbolt 30 is in locked position in the strike the pawl 66 will engage the transverse recess 69 of the bolt holding the same in place. if the door is open and the recessed portion 70 is beneath the follower 72, the subsequent closure of the door will release the latchbolt 30 from the latch 42, driving it through the opening 49 in the striker plate 47, and the end of the bolt 30 would strike the beveled end of the pawl 66 causing it to be pivoted to an out of the way position until it can eventually fall into the transverse slot 69, thus locking the bolt in place.

Upon leaving a residence and wishing the same to be secured against entry by a key or any unauthorized entry the push lock plug 62 is moved inward relative to the cylinder 59, placing the recessed portion 70 of the bolt 65 beneath the cam surface 72. This permits the pawl to be in the locking position. To release the lock a key is merely inserted in the keyway 63 to release the push lock plug, allowing the same to be withdrawn partially from the cylinder 59.

It will thus be seen that it is necessary for one gaining admittance with the lock in the secured position that he must also find a key or pick the lock of the push lock plug 62 in order to be able to gain admittance rather then merely releasing the inside knob 12 of the lock-actuating unit.

Having thus described the invention, what I claim is:

1. A retractable latchbolt structure for use with a lock structure having a retracting mechanism operative to afford linear retractive force, said bolt structure comprising a latchbolt housing having opposite ends,

a latchbolt in said housing and movable longitudinally in said housing from an extended position beyond one end of said housing to retracted position in said housing, said bolt being formed with a longitudinal bore,

a retracting bar positioned in said housing and in said bore of said bolt, said retracting bar extending beyond the other end of said housing when said bolt is in retracted position, and

lever means for connecting said housing, said bolt and said bar for retaining them together and affording relative movement therebetween and affording, upon a retractive force being applied to said retracting bar, relative movement of said bolt exceeding the retracting movement of said bar relative to said housing.

2 A structure according to claim 1 wherein said structure further comprises spring means positioned between said retracting bar and said bolt to normall urge said bolt to extended position and greater separation etween opposite ends of said bolt and said bar.

3. A structure according to claim 2 further including releasable catch means positioned in said housing and biasing means for moving said catch means toward said bolt for retaining said bolt in retracted position when moved thereto and operative upon receiving a force acting against said biasing means to release said bolt.

4. A structure according to claim 3 wherein said bolt in its normal retracted position projects beyond said one end of said housing and is movable against said spring means to a fully retracted position in said housing and wherein said catch means projects beyond said one end of said housing for engagement with a strike plate to release said catch means from said bolt upon said engagement by moving said catch means against the bias of said biasing means.

5. In a lock structure having a pair of opposed knobs and a bolt-retracting mechanism, a latchbolt structure extending transversely thereto, said latchbolt structure comprising a latchbolt housing, I

a latchbolt slidable axially in said housing from an extended position to a retracted position, said latchbolt being formed with an axially extending bore and being formed with an axially extending slot opening along one longitudinal edge of the bolt and communicating with said bore, and having means defining a wall opening in the opposed edge of said bolt communicating with said slot,

a retracting bar slidably received in said bore of said bolt and having a transverse opening therethrough,

a lever pivotally mounted at one end for movement about a fixed axis on said housing and extending through the slot in said bolt, through the transverse opening in the retracting bar and through said wall opening in the bolt, and

spring means biasing said latchbolt to an extended position relative to said retracting bar, whereby actuation of said retracting bar through a predetermined extent causes pivotal movement of said lever to retract the bolt to an extent greater than the movement of said bar as determined by the length of the lever and the spacing of said retracting bar in said bore from said wall opening in the latchbolt.

6. The lock structure according to claim 5 wherein said bolt includes shoulder means adjacent one end thereof and said structure further comprises releasable catch means positioned in said housing and biased toward said bolt to engage said shoulder means when said bolt is in said retracted position to retain said bolt in retracted position.

7. The lock structure according to claim 5 further comprismg a strike having a strike plate with an opening adapted to receive said bolt and a frame surrounding said opening on one side of said plate,

bolt-locking means supported by said frame-comprising means for releasably retaining the extended end of said bolt in said opening in the strike plate, and

said bolt having means defining a recess in said bolt for cooperation with said bolt-locking means.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1262435 *Apr 6, 1916Apr 9, 1918Gorden G BergElectrically-controlled lock.
US1302873 *Nov 6, 1913May 6, 1919Gilbert W StiffDoor-latch.
US1330693 *Apr 1, 1919Feb 10, 1920Fisher Joseph EarlDoor-lock
US2010237 *Mar 10, 1934Aug 6, 1935Theodore H JosephLock
US2575465 *Jan 23, 1948Nov 20, 1951American Car & Foundry CoLocking device for sliding doors
US3112944 *Dec 5, 1960Dec 3, 1963Independent Lock CoDeadlocking auxiliary latch construction
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3919869 *May 15, 1974Nov 18, 1975Zeiss Ikon AgMagnetic door lock system
US4087121 *Mar 14, 1977May 2, 1978Davis Thomas RDead bolt lock
US4897961 *Oct 17, 1988Feb 6, 1990Shine Jerry PReleasable mount for window grilles
US5452928 *Mar 17, 1994Sep 26, 1995Donald; Joseph G.Sliding door self-latching apparatus
US5529351 *Mar 1, 1995Jun 25, 1996Donald; Joseph G.Sliding door self-latching apparatus
US5647233 *Sep 25, 1995Jul 15, 1997Chung; Kuan-ChinDoor locking mechanism
US5816629 *Jan 11, 1996Oct 6, 1998Grodon Lock Inc.Sliding door latch with self-retracting finger pull
US6339944May 10, 2000Jan 22, 2002Victor Stanley, Inc.Locking mechanism for trash can receptacle and other doors
US7357429 *Jun 29, 2006Apr 15, 2008K.A. Schmersal Gmbh & Co.Safety lock
US7726706 *Jul 23, 2007Jun 1, 2010Control Dynamics Inc.Latch mechanism for gates and the like
US20070029813 *Jun 29, 2006Feb 8, 2007Manfred EichenauerSafety lock
US20070262589 *Jul 23, 2007Nov 15, 2007Control Dynamics Inc.Latch mechanism for gates and the like
USRE38693 *Oct 5, 2000Feb 1, 2005Newfrey LlcSliding door latch with self-retracting finger pull
WO1994029553A1 *Jun 2, 1994Dec 22, 1994Kibble Anthony WSliding latch
U.S. Classification292/167, 292/341.17, 292/335
International ClassificationE05B63/00, E05B63/12
Cooperative ClassificationE05B63/128
European ClassificationE05B63/12H