US2772905A - Door latch mechanism - Google Patents

Description

L. F. DUSING I 2,772,905

DOOR LATCH MECHANISM Filed July 14, 1954 Dec. 4, 1956 fj i. 3

- INVENTOR. E 'd, '4 LEON E DUS/NG @wa, MMYQz I A7 7 ORNEYS.

- 2,772,905; C noon LATCHVMECHAQNI'SM. 1

i Leon F. Dusing, Kenmore, N. Y., assignor to Dusing and Hunt, Inc., Buffalo, N. Y.

Application July 14, 1954, Serial Ne. 442,,219

7; Claims. c1. 292

YThe'present invention relates generallyto multiple latch door locking arrangements, and more particularly is ,directed to a spring latch arrangement which is especially adapted for holding massive fire-resistant doors in closed position even under extreme temperature conditions} 'Anobject of this invention is to provide a multiple spring latch arrangement for mounting along the edge of a door, wherein a main latch portion thereof will be arranged to be mounted in outwardly, ofisetrelation as compared to a plurality of co-operating spaced auxiliary latch units, the auxiliary latch units being operable upon actuation of the main latch units to retract for clearing their respective door jamb striker plates, f whereby all frictional forces incidental to locking ofthe' spring latches will be concentrated in the area of the main spring latch'to provide a relatively easily ope'rable and etficient door latching mechanism as compared with prior, art multiple spring latch mechanisms of this type. Another object of this invention is to provide latch operating means in a multiple spring latch arrangement of theaforesaid type including latch interconnection means adapted to be automatically 'disengagedfromeach ofthe respective latch' meansunder pre-determined elevated temperature conditions in order to preclude .the possibility of such latch means being forced into dooropeningrposition as a result of wrapping'of the connecting lihkage due to attainment of such elevatedtemperature eonditionsLf a v.1 I Still another 'object'of this invention is to' provide a multiple spring door latch arrangement embodying an offsefactuating unit, in combination with latch operating means provided with latch interconnection means of the aforesaidtype. a a n 1 Other. objectsfland jadvantages of this invention will appear in thesp'e'cification hereinafter. In the drawing: A I, Q Fig/[shows a general perspective View of a fire dqor embodying one form of the present invention; 1"

Fig.1 2 is, a fragmentary end levational view of: the devicepshpwn'in Fig, l", being'pa'rtially insection tomore clearly illustrate latching mechanism of the present invention; t JIFig, 3 isa fragmentaryside elevational view of the .device shown in Fig. 2 with the latch mechanism casing being omitted; and, z 1

, Fig. 4 is a,fragmentarysectional.view takengen'er'ally along the line Iv -IV. of Fig. 3. l J l f keferring nowtmore particularly to the drawing, the embodiment of the invention illustrated therein comprises. a fire-resistant door ,10, a main latch mechanism 12, supplementallatch mechanisms, 14 311(116, latch connection rneans 18, latch'handleslfl and 22, and a latch casing ,24' Figs. 1, 2 and 3.). t 1 f The main latch .mechanism 12 is show'n to be mounted pa a'flafnged supportmember 26 by 'a'ffixation to a central 'its fps o .2 reof t m m b ut bymeans'of a plurality" of screws 29 to the upper portion Patented Dec. 4, H256 of the door 10 adjacent a side-edge thereof (Fig; 3). A main latch casing portion 30 will be secured to the offset portion 28 by means of a plurality of screws 32forfurther supporting the main latch as moreparticularly described hereinafter. t t The 'upper portion of the casing-30 is provided with a crank pin 34 fixed in the walls thereof for the purpose of pivotally mounting a bolt-actuating bell crank-'36; The bell crank 36 has a bolt-actuating arm 38 arranged to depend downwardly between -the inner side portion 39 of a main bolt member 40 and the outer face of the sup"- port flange portion 28. An opposed crank arm-420i the crank36 extends away from the pin 34 to provide a crank actuating arm portion. t? v These crank arm portions 38' and 42 are limited against further clock-wise movement from the: position 'shown'in Fig. 3 by means of a casing-abutment portion 43 as more fully discussed below. l

The main bolt member 40 is shaped in the customary manner in order to have a cam surface portion 44 at its outer end for hitting against a door jamb striking plate 81 (shown in dotted lines in Fig. 2) to cam the bolt into re tracted position,the back end portion of the main bolt 42 being cut away to provide a recess 44 therein into which extends one end of a compression spring supporting member 46 having its opposite end fixed to the side wall of the casing 30 (Fig. 3) A compression spring member ,48 fits over the support member 46 so as to. be compressed between the side wall of the casing 30 and the base portion of the recess 44 to resiliently urge the main bolt 40 outwardly into its striker plate engaging position. I

The inner side portion 39' of the main bolt 40 is'pro vided with a shoulder portion as indicated at 50 in ablatting relation to the rear edge portion of the depending crankarm 38, and also a protuberance 52 in spaced re1ation to the, portion 50 for abutting the ,front edge portion of the crank arm 38 (Fig. 3) whereby the main bolt 40 will be actuated between open and closed positions responsive to rotary movements of the crank arm 42 The abutment portion 43 of the crank 36 limits pivotal movement of the crank in a, rotary clock-wise: direction so as to retain the main bolt 40 against further, movement outwardly as a result of the resilient surge of the spring 48'and thereby will maintain the bolt in assembled relation while being free to be cammed backwardly during a door closing operation as by striking the keeper plate 81.

The latch connection mechanism 18 will memes a crank actuating member 54 disposed generally parallel to the edge of the door 10 preferably inwardly of the latch units 12, 14 and 16 as shown in Figs. 2 and 3. The member 54 is of generally elongate form bent at its upper end into an ofiset portion 54(a) as more particularly noted below (Figs. 2 and 3). i

The latch units Hand 16 will be constructed in a manner similar to that described above for the main latch unit 12 with the exceptions noted below. Thus, the latch units 14 and 16 will include latch housings 56-58; supplemental latch bolts 60-62; compression latchbolt springs 64-66; pivotally mounted bell cranks 67-968 each having crank arm portions 72 and 74 and a casing abutment portion 76; the latch bolts each having a shoulder 78 and a protuberance 79 f onve'njgaging the crank arm portions 72 (Figs., 2 and 3); these partshe'irlg constructed and arranged'in a manner similar to their corresponding parts as described above for the main latch 12. One exception from the arrangement of the main latch 12 is that the housings 56 and 58"of the latches 14' and 16 preferably will be aflixed directly "to the center and lower portions of the door'10 insubstantially vertical alignment with the unit 12 but'being' ofis'e't from this unit'in a direction'toward the mounting surface Another cxoeption. from theaarrangemeutg of; the main latch; 12 isthat. the latch}, bolts 60Jand 62of; the supplemental latchesl4 and. ;1f6 ;-will be; provided with; integral springmountiugtpedestal portions -46(.a) and; 56th) ex tending rearwardly from cut away recesses 44(2z and.

44.(b): in. the-back end thereof; for. supportingthe compression -,springs'6 4,-66 in place; of mounting these pedestal portions integrally with their. casings. asin the case, of: the main.-latch 12, ,These pedestals .'46( -a fand 46( 2) willextendthroughnheirrespective casings 5 653 for'abutme ntaga nst a l nge p o o H r se angle-iron; tabs;46(c);and- 46(d) fixedto the member 54 aszshown. iu.Fig, ,3. :Thus the supplemental-latch bolts '60 and 62 will be precluded from retractionagainst .the

resilienturge'ot, their springs 64-66 except uponractuationbfthe-mainlatch mechanism 12 into retracted position. ,7.

As shown most clearly in Fig. 3, the crankconnecting member 54 -will bepivotally connected, in a manner maaob more fully described below, at spaced positions along 7 its length to the outer ends of the respective bell crank arrnportions 36-74- -74:of the respective latch mechanisms 12, 14 and 16. Of course, it.will be appreciated as is commonly known in the art that the handle members and 22 will be mounted on a spindle member 80 titted through the door 10 andkeyed by way of example 7 to the bell crank 7 f the latch unit 14. ThusQrotation of the handle members 20 or 22 will simultaneously cause all of the bell cranks to retract against the urge of'their respective springs 50, 64 and 66 by virtue of their interconnection through the mediumof the member 54. for 'thepurpose of manually opening and closing a door, the handles and the latch-bolts of the latch arrangement automatically. returning to their normal positions upon release thereof.

v It will be appreciatedto be a particular feature of the present invention that by virtue of the offsetmounting of the. main bolt 40, the cam portion 44 thereof will strike thedoor striker. plate portion of'its respective keeper plate 81 (shownin dotted linesin Fig. 2) in advance of the arrival jotthe supplemental bolts and 62, ofthe latch units 14 and 16 at their respective keeper 'plates'81(a) and 81(b) (also shown in dotted lines in Fig. 2). Thus, forfexa mple, the intertia ofthe door when swung toward closed, position will provide siiflicient force to cause the suitable means so asto be integral with the member The lead fill 88 is provided with wear-bushing 90substantially centrally thereofjfor supporting a connecting pin 92 in journaled relation therethrough. The pin 92 is headed at one end as shown at 94 for pivotally connecting the crank arms as for example the arm portions 74 (Fig. 4), to the member'54 andwill be provided with a cotter pin 96 at its opposite end for retaining the parts in assembled-relation.

Thus upon attainment of the preselected melting point of the above fill 8 8, the pivotal inte'rconne'ctiojn between the member 54 and the bell cranks will be released. Hence,-in the event-of a fire,'or extreme' heat-condition in the vicinity of doors embodying-the invention, the multiple latches of the present latching arrangement will become individually operable latch units whereby warpage of the member 54 will not be likely to cause the latch bolts toretract to permit the door to open atanjnopportune time before the fireor extreme temperature c'o'ndition is brought under. control.

While one particular embodiment of the presentinvention has. been shown and particularly described in detail herein, it will beunderstood that the invention is not so limited but thatvarious changes and modifica tions may be made therein without 'departing'from the spirit of theinvention or thescope of the appended claims.

What is claimed is:

V 1. In a fire-door construotion, a multiple latch bolt door locking rarrangement comprising .a' main latch bolt assembly operably connected to. a plurality of supplemental latch bolt. assemblies arranged in ventical=lyaligned relation adjacent the-edge'of afi re-door, each of the latch. bolt assemblies having resiliently outwardly urged ousmovements thereof, said "main latch bolt assembly being offset laterally away from the inside dooriface out of alignment wi-tht-he supplemental latch bolt assemblies whereby the bolt means of said main latch boltassembly will strike its keeper plate in advance of the arrival of the bolt means of the,supplernental latch, boltassemblies striker plate portion of the keeper plate 81. to bear against :the cam portion 44 of the main boltQ40 to overcome the .resilient'urge of the compression spring 48* acting thereon and also to simultaneously pivot, the bell crank member 36 about its pivotal mounting 34-for actuating the member 54to simultaneouslyrotate the bell crank members 7.4,.of the latch devices14 and 16 and thereby, to retract their respective latch bolts 60 and 62 in advance of their arrival at the door jamb.

, Therefore, by virtue of the above described arrangement,.f'rictional contacts between the bolts,60 and 62 and their respective keeper plates"811(a) and, 81(-b) will be avoided to provide an improved highlyv el'licient multiple bolt door locking arrangement in-which the; number of ivear'points along the'door jamb will be reduce'd, This will, of course, reduce maintanence costs and will also increase the useful life of locking arrangementsembody a low meltingrmaterial 88, as forexample lead; by any gate slots 82,84: and, 'These slotswill be filled with at 'theirrespective' keeper plates, whereby the bolt means in said main latch bolt assembly will be retractedupon striking its keeper plate and-thereby simultaneously retract the bolt means of the supplemental'latch bolt ass-em bl-iesout of contactwith their'respective keeper plates,

.2. In a ike-door construction, a multiple bolt door locking arbangement'including a'm'ain bolt, a plurality of supplemental bolts arranged in vertically aligned re lFa-tion adjacent the edge of a fire-door, resilient means urging said bolts into door closing posit-ion, aplurality of bell crank means being pivotally mounted in connection with said door bolts for movements therewith, means pivotally interconnecting said bell .crank'means so that movement of one of said bolts against the urge ofsa'id resilient means will correspondingly retract the other bolts, said main bolt being mounted" inwardly relative to-the other bolts so :as tostrike its door jamb keeper plate in advance of the arrivalo'f the other boltsjwhereby the other bolt means Will'be simultaneously retracted for fitting into their respective keeper plates.

' 3.I'n a fire-doorconstructiomfin combination, apl-urality of spring-pressed bolts in operablyin'tenconnected relation for. simultaneous retracting movements "responsiye' to actuation of 'any one fthereofijdoor jamb keeper plates having a bolt striking portion, oneof 'saidbolts being positionally offset out 'of' alignment with the re- 'maining latch bolts in order that the formenw-il l' strike pec ve.str k nsizd t n o o u e sai fothe at bolts-toretraet toclear their'respeetivekeeperplate striking portions incidental to a door closing operation so as to be fitted into their keeper plates with substantially no frictional contact therebetween.

4. In a fire-door construct-ion provided with a plurality of spring latch bo'lt means at spaced intervals along a side edge thereof, bell cranks each having one arm in engagement with a corresponding bolt means, the other arms of said bel-lcranks being pivot-ally connected to an elongate link member by means of a pin member journalled in a bushing supported in a bushing support portion of said link member, the bushing support portion having a preselected melting point, said bolt means being linked for simultaneous operation except upon attainment of said melting point of said bushing support portion whereby Warping of said link member due to elevated temperatures will not actuate said bolt means to open the fire-door.

5. In a fire-door construction, a plurality of spring latch bolt means mounted at spaced intervals along a side edge of a fire door, latch bolt actuating means being in operably interconnected relation with each of said latch bolt means for normal simultaneous actuation thereof, said latch bolt actuating means being arranged to embody a relatively low melting point material at spaced positions therein for supporting each of the points of interconnection thereof with each of said spring latch bolts in order that upon occurrence of a temperature above said melting point in the vicinity of the fire-door said supporting material embodied in said member will melt to release said points of interconnection.

6. In a fire-door construction, .a multiple latch door locking arrangement comprising a main bolt, a plurality of supplemental bolts, said bolts being arranged in vertically aligned relation adjacent the edge of a fire-door, keeper platemeans associated with the door jamb, spring means resiliently urging each of said bolts outwardly into door closing position, means pivota-lly interconnected to said bolts for normal simultaneous actuation thereof,

said means being arranged to embody a low melting point material for normally supporting the pivotal connections thereof with said bolts whereas upon the occurrence of temperatures above the melting point said material will melt to operably disengage said means from said bolts, said main bolt being offset out of alignment with the supplemental bolts in a direction away from the inside face of the door so that said main bolt will strike said keeper plate means in advance of the arrival of the supplemental bol-ts thereat during closing of the door Whereby said main bolt will be retracted as a result of striking said keeper plate means and thereby will simultaneously retract the supplemental bolts out of contact therewith.

7. In a fire-door construction, a plurality of spring pressed latch bolts mounted at spaced intervals along a side edge of the fire door, a door ja-mb, keeper plates mounted in said door jamb in horizontal alignment with said latch bolts, one of said keeper plates being laterally offset in the direction of approach of said latch bolts, first means associated With one'of said 'latch bolts for manual retract-ion thereof, second means connected to said bolts to normally permit simultaneous actuating movements thereof responsive both to manual operation of said first means and retraction of one of said bo'lts as by camming it to retract incidental to its striking the ofiset keeper plate in the door jamb, said second means incorporating a low melting point material arranged for normal support of the points of connection with said bolts and operable release thereof upon attainment of the melting point temperature in the vicinity of the door.

References Cited in the file of this patent UNITED STATES PATENTS 928,904 Cottrell July 20, 1909 1,006,211 Hermon Q. Oct. 17, 1911 1,086,125 Berry Feb. 3, 1914 1,951,628 Prost Mar. 20, 1934

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