US1502475A - Latch mechanism - Google Patents

Description

MW 37 BY WWW BE] 5 Juiy 22 1924. LSQZAWS J. LEDW INKA LATCH MECHANI SM Filed Aug. 27, 192] 2 Sheets-Sheet 1 1 N V EN TOR.

JbSE'PH LEONA/K14 Juiy 22, 1924. magma J. LEDWINKA LATCH MECJHANISM Filed Aug. 27. 1921 2 Sheets-Sheet 2 JOSEPH LEDW/NKA WW W By ATTORNEY.

Patented duly 22, 1924.

w hheld JOSEPH LIEDWINKA, 0F PHEADELPHIA, PENNSYLVANIA, ASSIG-NGE T0 G. BUDD MANUFACTURING COMPANY, OE PHELADHJPHIUL, PENNSYLVANIA, A COR- PORATION OF PENNSYLVAEIA,

LATCH MECHANISM Application filed August 27, 1921. serial No. 598,0 52.

anism which will require the application of only a very slight pressure or force, to the door in closing it, in order to retract the latch bolt.

Another object of my invention is to provide an improved latch construction in which friction between the relatively moving parts is very largely reduced or eliminated.

Another object of my invention is to provide an improved latch construction in which the latch bolt will be securely retained in looking position by engagemnt with the keeper, without the necessity for employing comparatively stiff or strong springs for that purpose.

Another object ofmy invention is to provide an improved latch construction in which a swinging latch bolt is withdrawn from looking position by the actuation of a slidable bolt-operating member.

Further objects, and objects relating to details and economies of construction and operation, will definitely appear from the detailed description to follow. Myinvention is clearly defined and pointed out in the appended claims. A structure constituting a referred embodiment of my invention is illustrated in the accompanying drawin s, forming a part of this spec1ficat1on,in wh c Figure 1 is .a plan view of a latchemy bodying my invention.

Fig. 2 is auview'of vation. I

Fig. 3 is a transverse, sectional view through the latch, taken on the line the latch in side ele-' of Fig. 1, and showing the operating spindle and handles.

Fig. 4 is a sectional view on the line 4-4 of Fig; 3, showing the parts for ac-. tuating the cit-operating member.

Fig. 5 is a sectional view taken on line 5-5 of Fig. 1, and i Fig. 6 is a perspective view of the boltoperating member.

In the drawings, the same reference numeral refers to the same part throughout the several views, and the sectional views are taken looking in the direction of the arrows at the ends of the section lines.

It is among the special purposes of my invention to provide a latch belt which is pivotally mounted to swing into and out of looking position, and which is so arranged that when in locking position the locking strain of the keeper is taken by the pivot stud of the latch bolt in a direction radially towards the axis of the saidstud, thereby relieving the operating devices for the latch bolt from such strains. To accomplish this result in one form ot-embodiment of my invention.

the end surface of the swinging latch bolt is curved to an arc concentric with the pivotal axis ofthe latch bolt and this curved surface is enga ed by the keeper when the latch bolt is in coking position. Normally,

in accordance with my invention, the latch bolt isyieldin ly maintained inposition for its forward side surface to engage the keeper By imposing the strain of the looking I engagement of the latch bolt and keeper, when the door is'in closed-position, upon the pivot of the latch bolt, I am enabled to eliminate and avoid the use of stiff or strong springs for taking. such strains, while at the same time securely retaining .the lock in its lockin position.

- It is also among t e special purposes of my invention to provide operating means for the latch bolt, which, while permitting the yielding swinging movement of the latch bolt, above referred to, during the closing movement of the door, may be operated by suitable handles, easily and readily, and

i with the expenditure of only small force,

toefl'ect a manual withdrawal of thelatch bolt from locking position when it isdesired to open the door. To accomplishthis result, in accordance with my invention, I propose to employ means suitably connected to the swinging latch bolt, and which are mounted to slide rectilinearly in a direction tangential to the arc of swing of the latch bolt, and I propose to reduce to a minimum the area of surface contact of the sliding parts in order to reduce the friction of such sliding movement.

I also provide a simple arrangement of manually operable means to. effect the withdrawal of the latch bolt, from its locking position, whenever desired, to effect the opening of the door. To this end I propose to employ a roll-back member arranged to engage the latch bolt-operating connections, and'yieldingly held in. its normal position in which it permits the latch to be maintained in its locking position.

These various objects and purposes may be accomplished in many diflerent wa s, and, while I have shown and will-now scribe an illustrative simple and eificient flange 11 and a swingingl embodiment of my invention, I wish it to be understood that in the broadest scope of my invention, as defined in the claims, I

do not desire to .be limited or restricted to thebase plate 10 near thefiange 11 and provided with a pair of ears15 carrying a pivot in 16 on which the latch bolt 17 is 'pivota 1y mounted. The latch bolt 17, if

desired, may be formed into a recess 25 .epening through its rear face, so that it'is substantially hollow and "is thereby correspondingly reduced in weight. The 1 end surface 18 of the latch bolt is curved to an arc concentric with the axis of the pivot 16, and the front side of the latch bolt lies arallel to a radial plane through said axis. bolt-operating member 19 is provided for actuating the swinging latch bolt. This bolt-operating member is mounted so as to slide relative to the base plate and it has an extended portion 24 which is pivotally connected to the latch bolt, as bythe pin 26. The body ortion of the member 19 has an elongate central opening 20, and, at, the end opposite the extension 24, a ijde lug 21 which works in a slot 22 ormed in the base. plate 10. The portion of thel'bolt-operating'member 19 adjacent I the lug 21, and the corresponding end of the central opening 20, is thicker than the body portion of said member 19, and is provided with the-projecting portions 23 on the face thereof which is presented toward the base plate-10, said projecting portions forming shoulders 40. A spring 27 mounted on a post 42 carried by the base plate enga es the end of the member 19, adjacent the ug 21, and normally exerts its tension to urge the said member toward the flange 11, so asto swing the latch bolt 17 forwardly on its'pivot into projected positionas clearly shown in Figs. 1, 2-and 3.

A bridge 30 mounted on the base plate 10 extends over the bolt-operating memvided to manually retract the bolt. For

this purpose I have shown a roll-back 3.8

which is journaled in the base plate at 29, and in the bridge, 30, at 31. The rollback, 38, in the illustrative form shown,

has laterally-extending fingers 39 which her 19. Any suitable means may be proroll-back to restore it to normal osition after it has been displaced there rom in retractin thebolt. The roll-back is provided with a square opening or passage 35 through which exten s the s uare spindle 34, to which the operating andles 36 and 37 are attached. This is one of the customary expedients for actuating a rollback and it is obvious that other means may be utilized for that purpose. When this latch construction is used in all-metal doors,

having two spaced panels between whichv the latch is inserted, I provide a support,

32 for one of the escutcheon plates, which is secured to the bridge '30 at 33, and has a central opening through which the spindle 34 extends. The latch mechanism cooperates with the usual keeper (not shown). When the door, carryin this latch mechanism, is swung to close position, the edge of the keeper engages the front side or edge of the swinging latch bolt 17. The resist- 27, the friction between the latch bolt and its pivot, which friction is very small, and the friction between the bolt-operating member 19 and the bridge 30, and base plate 10 at the points where said member is guided by such parts. This latter frlction is reduced because the area of the parts in surface contact is greatly reduced, the only portion of the bolt-operating. member having such sliding contact being the thicker portion adjacent the lug 21. 7 Furthermore, it will be observed that the pressure aplied in closing the'door when ,the front ace of the latch bolt engages the keeper,

is translated into a force actin in the direction of the length of the bjo t operating member and hence there is no tendency, as in the ordinary sliding-bolt construction, to press the bolt-operating member toward one of the parts on which it slides, which otherwise would increase the sliding fric-- tion. When the door in closing has moved sufficiently far to permit the edge of the keeper to pass the outer end of the latch bolt 17, and to receive the are surface of the latchbolt thereagainst, the spring 27 acting on the bolt-operating member 19 swings the latch bolt forwardly to and maintains the same in its normal locking position with the keeper in engagement with the end surface 18 of the latch bolt. When in this position, a force exerted on the door in the direction to open it is applied to the end of the latch bolt in a direction radial of its pivot, the resultingstrain is taken by the latch bolt pivot and is not imposed upon the bolt-operating member 19. Consequently, a very light spring is all that is needed to maintain the bolt-operating member 19 in locking position. When it is desired to retract the latch, the operating spindle 34 is turned in either direction by one or the other of the handles 36, 37. This causes one or the other of the fingers 39 of the roll-back to press against a shoulder 40 on the bolt-operating member 19, and slides said member back against the tension of spring 27, thereby retracting the latch bolt through the opening 13 out of en aging relation with the keeper 'on the 0017 jamb. The spring 28, acting on the flat back of the roll-back, restores it to normal position when the handle is replaced and the spring 97 presses the bolt-operating member 19 to its normal position to again project the latch bolt through the opening 13 and into the projected position shown in the drawings.-

By reducing the friction as described and by providing a construction in which only a light spring is needed to project the bolt, I have attained objects of my invention and produced a latch which is remarkably sensitive, that is to say, a very sli ht force applied to the door will be su cient to latch-it.

What I claim as new and useful and of my own invention, and desire to secure by Letters Patent is:

1. A latch mechanism comprising a base plate, a swingin latch bolt mounted thereon, a bolt-operatlng member slidably mounted on said base plate and provided with a lug sliding in a slot therein, the body portion of sand member being spaced from the base plate, said member bein connected to said latch bolt, a rotatable ro l-back engaging said bolt-operating member to actuate It)heksame, and means for rotating said roll- 2. A latch mechanism comprising a base plate a swinging latch bolt mounted thereon, a bolt-operating member connected to said latch boltand having its body portion spaced from said base plate but guided for sliding movement thereby, a roll-back positioned between said base plate and the body portion of said bolt-operating member and engaging said member to actuate the same, and means for. operating said roll-back.

3. A latch mechanism comprising a base plate, a swinging latch bolt mounted thereon, a bolt-operatin member connected to said latch bolt and liaving its body ortion spaced from said base late but gui ed for sliding movement thereby, the body portion of said'member being provided with a central opening, a roll-back extending through said central opening and having portions working between the body'portion of said bolt-operating member and the base plate and engaging said bolt-operating member to actuate the same, and means for operating said roll-back;

4. A latch mechanism comprising a base plate, a swinging latch bolt mountedthereon, a bolt-operating member connected to: said latch bolt and having its body ortion spaced from said base plate but gui ed for sliding movement thereby, the body portion of said member bein provided with a central opening and pro ecting shoulders on each side thereof, a roll-back extending through said central opening and having portions working between the bod portion of said bolt-operating member an the base plate and engaging said projecting shoulders to actuate the bolt-operating member,v and meaiis for operating said roll-back.

5. A latch mechanism comprising a base plate, a swinging latch bolt mounted thereon, a bolt-operating member connected to said latch bolt and having its body ortion spaced from said base plate but gui ed for ing through said central opening. and having portions working between the body portion of said bolt-operating member and the base plate, and engaging -said' projecting,

shoulders to actuate the bolt-operating member, and means for operating said roll-book.

6. A latch mechanism comprising a base plate, a swinging latch bolt mounted thereon, a bolt-operating member connected to said latch bolt and having its body portion spaced from said base late but guided for sliding movement there ,y, the body portion of said member being provided with a central opening, projecting shoulders on each side thereof, and a lug sliding in a slot pro- Vided in said base plate, a roll-back extend ing through said central opening and having laterally extending fingers working between the body portion of said bolt-operating member and the base plate and engaging said projecting shoulders to actuate the bolt-operating member, and means for operating I said roll-back.

7. A latch mechanismcomprisin a base plate, a latch bolt pivotally mounte on said ase plate, a bolt-operating member mounted on said base plate to slide in a right line and pivotally connected to said latch bolt, a roll-back engaging said bolt-operating member to actuate it in one direction, a spring engaging said bolt-operating member to actuate it in the opposite direction, a spring engaging said roll-back to restore it to normal positlon, and means for operating said roll-back.

8. A latch mechanism comprising a base plate, a swinging latch bolt pivotally mounted on said base plate, a bridge mounted on said base plate, a bolt-operating member connected to said latch bolt and slidable between said bridge and base plate, a rollback journaled in said bridge and base plate and engaging said bolt-operating member to actuate it in one direction, and means for pivotally connected to said latch bolt and uided for sliding movement between said ridgp and base plate, said bolt-operating mem er having a body portion spaced from said bridge and base plate and a thicker portion having sliding contact therewith, and shoulders projecting from said thicker operatin portion toward the base plate, a, roll-back ournaled in said bridge and base plate and having fingers working between said boltoperating member and the base plate and engaging said shoulders to actuate the bolt pivotally connected to said latch bolt and uided for a sliding movement between said rid e and base late, said bolt-operating member havin a ody portion s aced from said bri'd e and base plate, a thic er portion having shding contact therewith, and shoulders projecting from said thicker portion toward the base plate, the body portion of said member being PIOVldGd'Wlth a central opening, a roll-back extending through said central opening and journaled in said bridge and base late, said roll-back having fingers working etween said bolt-operating member and the base plateand enga ing said shoulders to actuate'the bolt-operating member in one direction, and means for operatingsaid roll-back.

11. A latch mechanism comprising a base plate, a swinging latch bolt pivotally mounted on said base plate, a bridge mounted on said base plate, a bolt-operating member connected to said latch bolt and slidable between said bridge and base plate, a rollback journaled in said bridge and base plate and engagin said bolt-operating member to actuate it in one direction, an escutcheon support carried b said bridge, and means for operatin sai roll-back.

12. A late mechanism comprising a base plate, a latch bolt pivoted thereon, a bolt operatin member connected to said latch bolt an slidably mounted on said base plate, guide means on said member cooperating with the base plate, said member being out of contact with said base plate except for-a limited area adjacent said guide means, and means for actuating said bolt operating member.

13. A latch mechanism comprising a base late provided with a slot therein, a latch olt pivoted on said base plate, a bolt operating member pivotally connected to said latch bolt and having a lug sliding in said slot, the body portion of said member being out of contact with said base plate except for a limited area adjacent said lug, and means for actuating said member.

14. A latch mechanism comprising a base plate having a slot therein, a latch bolt pivoted on said base plate, a sliding bolt member pivotally connected to said late bolt and having a lug working in said slot, said member being out of contact with said base plate except for a limited area adjacent said lug, a spring engaging said member adj acent said lug to project the latch bolt, and means for retracting said member against the pressure of said spring.

15. A latch mechanismcomprising a base plate, a latch bolt pivoted thereon, a bridge member fastened to said base plate,'a bolt operating member ivotally connected to said latch bolt and sliding between said brid e and base plate, guide means on said mem er cooperating with the base plate,

said member being out of contact with said base plate and bridge except for limited ture.

JOSEPH LEDWINKA.

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