US2598526A - Door latch - Google Patents

Description

S. R. FRAIM May 27, 1952 DOOR LATCH Filed May 6, 1 949 Patented May 27, 1952 UNITED rsrnres JPATEENT names 3: DOOR LATCH SamuelRI Fraim', Lancaster, Pa., assignontiiE. T. -Frai1ii Lock Company, Lancaster; Pa; a corpuration' di' Pennsylvania ,ApplicatiomM-ay 6, 1949,.Serial No..-91,-809

I 5 Glaims.

This invention relates... toi .doorulatches. and more particularly to latches forscreen' doors,.and a principal object'ofi the invention is to. provide a latch of this. class which shall be relatively strong and rugged. and." also mechanicallyunbe relatively low.

Another obj ectfof' the, invention isto provide a latch device of thelstated"classconsisting essentially'of three primary parts including alever structure incorporating both; the outside .andjnside door handles and'also, aboltelement, a bracket which pivotallysupports the. lever .memher and which is adapted tov besecured-toithe door, and a keeper. element .of. simplellform adapted to be securedto" the door framforoperative engagement with the bolt .element carried in the lever structure.

The. invention .residesjtalso. .in. .certain,..novel structural features and mechanical devices hereinafter described.andillustrated in the attached drawings, wherein:

the mid portion of thehandl'e lever;

Figs. 7 and 8 are, respectively,.sectionalyiews on the lines 1--? and 8'8'o"f Fig. 1.; and

Fig. 9 is an enlarged view.,of..,the...bolt. and

' keeper showing the forces acting. thereon.

With reference to the. drawings; thelatch comprises the following elements; alatch actuating lover I which comprises an outer handle Zand an'inner handle 3, the lever .and handles being "made in the present instance ofeonel. integral piece; a bracketelement 4 to whichthe lever I is pivotally connected ,by. means of. aJpin' Sand which is attached to the inner face of'thedoo'r 6 by means of screws I, see' Fig.5, the.:expos'ed portion of the bracketappearing as a'plat 8.0n the inner face of the door, as'jillustrated; a keeper element 9 which,is.seouredtoltheldoor frame II, as best shown in'Figs; 1; 2 and.5;..a'nd a spring pressed bolt I2 which is.mount'ed in .the body of the-lever I and .which cooperatesiwith the keeper 9 as hereinaftenmore specifically. de-

' scribed to latch'the door.

complicated so that "the costof...produ'ction may 32 T With reference more;v particularly .to Figs? 2 andB, the lever I, in assembly, extends. through a transverse opening I 3 inthe' .door, 6;, this, opening' being circular-Kin. form,v as". indicated.v by

broken lines ,in",FigT The bracket element 4 overlies" the inner endof theopeningl3 and has within itself an ielong'atjed openi ng I01 through which thelever passes." The bracket hasfalso. a of. spaced .ears- I4 andIS which project into the openi g T13 and between ."which they lever I i pivotally supported. Thelever I has. at its mid-section. a pair "of spaeedprojecting ears .IB

. and'I I which in assembly and as shown infgig. 3

occupypositions at the innerfacesfof the ears "I 4 and'I 5 of the bracket me'mbeiA}. the ears I 4, I5, I6. and I7? having registering apertures .for reception'of the pivot pin 5 which connects the lever 'with' the bracket. In orderto. properly. locate the bracket on the door apair fofprojecting teats I8 is provided ontheinnerisurface of the plate 8 arranged to engagelthecylindrical wall of. the opening I3, these teats being soplaced with-respect: to the ears I4 andil 5 that when the earsengage onesi'de of the opening, see Fig. 2, the teats will engage the opposite side.

A'sbest shown in" Fig. 2, a coil spring'l 9 is supported on thepin 5 betweenthe. earsfIB andTI of the lever, one. end 'ZI of this spring seating against a su'rface22 of the bracket 4 and the other" end"l23."of the spring extending into. a transverse slo't24 in the upper sidefofthe lever I and seatingragainst one wall T25v ofthisrecess.

Thespring 119 being. undertension exerts pres- *suretending to turn the. lever I..or.its piv.ot..in a

'clockwise'idirection as'viewedv in Figs. 1 and 2. The-lever'maybe turned'about' theipivot 5m the .qppositedire'ction against" the .pressure of the spring by pulling the .handle 2 away.,from,the

door or by pressing the handle 3, toward .the door.

The outer end of the opening'liis normally closedby a'plate.26 which is. secured to. the door by screws 21. As shown. in Fig; 8 thisplate, has three teats 23, 29 and" T3I. projectin from .the inner side thereof which are arrang'edto engage the wallof theopeningl3 to thereby. locate the plate 26 on the outer faceof the doorJ The plate has an opening32 through which the lever I extends as shown in Fig. 2,.thisope'ningbeing elon gated .to afford clearance. forlthe..aforedescribed movements of the, lever Iiabo'ut the pivot 5..v Pivotally supportedagainst the inner-face .of the plate 26 is an inner plate 33;..this;plate,b.eing.,pivotally mounted uponi.the,teat 29.1.The plat .l33 has an opening. which embraces-the portion of. the lever I which .projectsther'ethrough .with small. clearance, as .best. shown in Figs. 2 .and 8.

The plate 33 has the effect of closing the elongated opening 32 in the plate 26 but being movable on the pivot 29 may accommodate itself to the different positions of the lever I so that in effect it constitutes a sliding closure for the said opening. By this means moisture and dirt is effectively excluded from the outer end of opening l3 of the door 6 and from the elements of the lever and bracket assembly which ar housed within said opening.

The bolt I2 is formed as best shown in Fig. 2. This element is generally cylindrical in form and has a pair of spaced cylindrical flanges 36 and 31, the latter flange being located at the inner end of the bolt and the flange 36 toward the other end. The flanges are dimensioned to fit neatly and slidably within the cylindrical bore 38 in the lever I in which the bolt is mounted. A pin 39 projects inwardly from the wall of the bore between the flanges 36 and 31 and by engagement with these flanges limits the movement of the bolt in the bore. A spring 4| in the bottom of the bore bears against the inner face of the flange 31 and tends to hold the bolt in the extended position in which it is shown in Fig. 2, this position being determined by the pin 39 which as shown engages the face of the flange 31. In this position the outer face of the flange 35 lies flush with the terminal end of the bore 38. which extends outwardly beyond the flange 31 has an outer beveled edge 43, and the sides of this end portion of the bolt between the bevel and the outer face of the flange 36 are under cut, as illustrated, or, in other words, slant inwardly from the inner edge of the bevel surface 43 toward the pin axis.

The keeper 9 is formed as shown in Figs. 2 and 5 so as to coact with the bevel surface 43 of the bolt and the inclined side wall 44 to cause retraction of the bolt when the door is closing and, when the door,is closed, to prevent such retraction of the bolt by pressure exerted directly on the screen. Thus the keeper 9 has at its outer side, i. e., that side which faces toward the door, an inclined surface 45 which when the door is moving towards closed position is engaged by the beveled face 43 so that a componential force will press the bolt inwardly against pressure of the spring 4| to an extent such that the bolt may clear the outer end of the keeper. It will be noted also that just inwardly of the bore 38 at the base of the handle element 3 the lever I has a beveled surface 46 which is disposed also for engagement with the inclined surface 45 of the keeper as the door is closing so as to cam the lever about the pivot 5 to an extent permitting passage by the keeper of that portion of the lever.

As the door is closing, the surface 46 will first engage the surface 45 of the keeper to turn the lever in the counterclockwise direction as viewed in Fig. 2, and subsequently when the surface 46 has cleared the end of the keeper the beveled end surface 43 of the bolt will contact the surface 45 to force the bolt 43 inwardly against the pressure of spring 4| to an extent permitting the outer end of the bolt to clear the keeper. Thereafter the lever is returned to the normal position, as shown in Fig. 2, by action of the spring 23 and the bolt 43 is projected to the normal position by the spring 4| so that the parts assume positions with respect to the keeper as shown in Fig. 2. In this position, by reason in part of the inclination of the axis of the bolt to the plane of the door and in part by the under- The projecting end portion 42 of the bolt cut walls 44 of the projecting end of the bolt which, as shown in Fig. 1, is engaged by the tip end 55 of the keeper, the bolt and keeper will be so interengaged that pressure exerted directly on the door tending to open the latter will tend only to force the bolt outwardly, so that the latch is positively maintained in operative position. With reference to Fig. 9, it will be seen that the force F exerted by the keeper 9 on the inclined surface 44 of the bolt I2 has a component .10 along the longitudinal axis XX of the bolt l2. The force F is normal to the surface 44 because of the relatively frictionless contact between said surface and the keeper 9. Only by movement of the lever as a whole, resulting either from an outward pull on the handle 2 or an inward pressure on the handle 3, can the terminal end of the bolt H. be released from the keeper.

At the top of the bracket 4 is a cylinder 4'! in which is slidably mounted a pin 43. A handle 49 attached to the pin 48 projects through a bayonet slot 5| in the wall of the cylinder 41, and a spring 52, see Fig. 7, in the bottom of the cylinder 41 tends to force the pin 48 upwardly in the cylinder. An inner reduced end 53 of the pin 48 extends through an opening in the bottom of cylinder 41 and the latter is so located that the end of the pin, when projected downwardly from the bottom of the cylinder will occupy a position as shown in Fig. 2 wherein it lies in close proximity to the side of the lever to thereby prevent a pivotal movement of the lever releasing the bolt l2 from the keeper. The pin 48 may be moved downwardly against thebase of the spring 52 by means of the handle 49, the handle 49 then being shifted transversely into the lower offset end of the bayonet slot 5| to retain the pin in the extended or lever-locking position.

This same pin may be used to retain the lever in a retracted position in which the bolt I2 lies clear of the keeper so that the door is free from the latch. Thus, when the pin 53 is projected downwardly into the recess 54 in the upper side of the lever I, as shown in Fig. '7, the projecting end of the pin will engage the side wall of the slide and hold the lever in the retracted position, as shown in Fig. 3, and in full lines in Fig. 1.

It will be apparent that the device is subject to modification in detail without departure from the invention.

I claim:

1. A door latch for engagement with a keeper on the door frame, said latch comprising a lever extending through the door from one side to the other and having a handle at each end, means for pivotally supporting said lever in the door, and a longitudinal bolt member slidably mounted in a guideway within the inner handle of the lever and extending therefrom in a position to engage the keeper and mounted for movement on a straight line converging at a substantial angle with the plane of the door in the direction of the keeper, the extended end of the bolt increasing in cross sectional area toward its outer end, whereby pressure of the keeper upon said diverging surface when the door is closed will act to maintain the bolt in extended locking position, said bolt effectively closing said guideway to the admittance of foreign matter, and resilient means tending to retain the bolt in the extended position.

2. A door latch for engagement with a keeper on the door frame, said latch comprising a lever extending through the door from one side to the other and having a handle at each end, means for pivotally supporting said lever in the door, and a longitudinal bolt member slidably mounted in a guideway within the inner handle of the lever and comprising spaced flanges, one at the inner end and another at its midsection, said flanges seating neatly in and effectively eliminating transverse motion of the bolt within the guideway, said bolt effectively closing said guideway to the admittance of foreign matter, and extending therefrom in a position to engage the keeper, and resilient means tending to retain the bolt in the extended position.

3. A door latch according to claim 2 wherein a pin is mounted in the guideway between said flanges to serve as a stop limiting the longitudinal movement of the bolt within the guideway.

4. A door latch according to claim 3 wherein the resilient bolt-extending means consists of a spring seated in the guideway and bearing against one of said flanges.

5. In a door latch, a lever extending through the door from one side to the other and having a handle at each end, a bracket secured to the inner side of the door and to which the lever is pivotally connected for oscillation in a plane approximately normal to the plane of the door, a bolt element carried by the lever inwardly of the pivot and arranged for inner engagement with the keeper on the door frame, said bolt being releasable from the keeper by a retractive movement of the lever about its pivot, a pin slidably mounted on the bracket, the axis of said pin being perpendicular to the plane of motion of the lever and displaced therefrom for projection into said plane of motion behind the lever to prevent the said retractive movement of the latter and also to front of the lever after the latter has been retracted to prevent return of the lever to the door latching position, and spring tending to retract the pin from engagement with the lever, and a handle element extending outwardly from said pin, said handle element projecting through a generally L-shaped aperture in the bracket and being movable transversely of the pin into the offset end of the aperture to thereby maintain the pin in leverengaging position against the presure of said spring SAMUEL R. FRAIM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 426,388 King Apr. 22, 1890 797,425 Haag Aug. 15, 1905 975,037 Hettwer Nov. 8, 1910 2,311,686 Olson Feb. 23, 1943 2,435,180 Ledin Jan. 27, 1948

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