US2454672A - Door latch - Google Patents

Description

1948. L. L. ROSENTHAL ET AL 2,454,672

DOOR LATCH Filed Jan. 1, 1945 v ,ISfinentor: Lawns/veg L Pox/yum K Patented Nov. 23, 1948 UNITED STATES PATENT OFFICE 2 45fl672 noon LATCH Lawrence L. Rosenthal, Los Angeles, and Robert B. Spencer, Huntington Bark, rCali'L, assig'nors to Technical Glass Qompany, Los .Angeles, Calif., a corporation of California application January 1, 1945,.Seriai No."57il,846

2 Claims. (Cl. -292---'D.)

This invention relates to and has :for an ob- I ject the provision oi an improved door latch 'oi generally conventional character butembodyin'g certain new and novel features which-particularly adapt the latch for indoor rather than outdoor purposes.

As usually constructed latches 'or looks adapted to receive my improvements are usually applied to bed rooms, bath rooms, etc, and are of the keyless type. erated by a pair of knobs-one on each side of a door-and include a sliding bolt which is spring urged into latching position in a metal socket carried by the door frame and a cam rotated by turning a knob on either side of the door and engaging shoulders on the rear portion of the bolt. If the door is to be locked against entrance or egress a key. or supplementary latch is required and, in many cases when a door is locked it has been impossible to gain entrance when the door is locked on the inside of a room.

Hence, it is an object of this invention to provide a combined latch and lock which will indicate in an attempt to open a door by the turn of a knob that the room is occupied and the presence of others is not desired, but, in cases of accident, illness or even death or other emergency, the operation of a simple unlock-device on the outside of the door will unlock the door and permit entrance to the closed room.

A further object is to provide a lock which by reason of the interposition between the bolt and the knobs of a connecting member will readily permit the latching of the door upon the closing thereof without requiring the turning of the knobs so to do and yet when the knobs, or either of them are turned, the latch will be retracted.

Another object is to provide a simple but effective combined locking and unlocking device embodying a pair of similar members-one on each side of the door-which may be independently operated for unlocking the door on both sides or for locking one side while the other is unlocked, and which are equally effective for unlocking the door when locked from an opposite side so as to afford admission to a room.

Other objects may appear as the description progresses.

We have shown a preferred form of latch in the accompanying drawings, subject to modification, within the scope of the appended claims, Without departing from the spirit of our invention. In said drawings:

Fig. 1 is a fragmentary sectional plan of a door to which our improvements have been applied Generallysuch latches are'opand showing the latch bolt extended for locking engagement with a socket on the-'do oriframe (not shown) Fig. 2 is a sectional plan of the same showing the bolt retracted;

Fig. 3 is a side view of the latch mechanism when detached fromadoor and show ing-th'e latch bolt retractedas in Fig. 2;

Fig. 4 is a cross sectional view on line i -'4 of Fig. 2;

5 is a perspective view of the connecting member between latch bolt and the knobs; and Fig. 6 is a perspective view of the latch bolt.

As shown in a preferred form our lock includes a two-part casing formed with hollow mating members i and 2. Bottom member I of the casin'g carries an escutcheon plate 3 suitably fixed to an end thereof as by means of screws 3a and which is usually countersunk in an edge of 'a door D. inwardly of plate 3 we provide a collar 4 which is notched at 6 to receive a lag t formed onthe endof the top member 2 so as to prevent the rotation of the casing members. Members I and 2 are held together as by means of one or more screws 'l'. The interior of member I is of arcuate cross section and is arranged to slidably receive a *bolt B of corresponding cross section at least throughout'a part of its "length. Said bolt, of course, extends through an aperture in plate 3, while its rear portion is bifurcated, as-at 8 and -9, said bifurcations terminating in shoulders Ill and IE, respectively.

Bottom member I has an upstanding post I! between which and bolt '13 a spring '13 is compressed and serves to urge the bolt into extended position from the lock, portions 8 and 9 strad dling said post as the bolt moves inwardly into the casing as when a door is opened or closed.

Rearwardly of the casing a pair of knobs K and K are fixed to a rotatable square shaft I4 which extend through the casing and door. A cam member C is journalled in members i and 2 and is fixed for rotation with the shaft and knobs. Said shaft extends through an opening IS in door D, plates l1, l1, and escutcheons l8, l8 on the door so that when the knobs K and K are turned the cam C will be correspondingly rotated for retracting the bolt B. Said cam member has usual shoulders l9, l9 laterally spaced thereon for engagement with shoulder portions 20, 20 carried by a connecting member A which is differentially slidable in the casing with respect to bolt B.

Member A has transversely spaced arms 2i and 22 at its forward extremity which overlie the furcatiohs 8 and 9 of bolt B and have depending 3 portions 23 and 24 adapted to engage the shoulders I l] and I I of bolt B, respectively, only for the purpose of retracting the bolt when the knobs K and K are appropriately turned. Thus said bolt may be retracted without turning the knobs as when a door is opened or closed. The rear extremity of member H is bifurcated so as to permit the rotation of the cam member therebetween, as shown in Figs. 3 and 5, and has an intermediate transverse bar 25 which is spaced rearwardly from post l2 so as to permit the longitudinal shifting of member A. Said bar has a perforation 26 therein adapted to receive either one of two axial transverse locking pins P and P, whereby the bolt B may be locked in retracted position when the knobs are turned for such purpose. By reference to Figs. 1 and 2 itwill be noted that the locking pins P and P' are of similar length and. form, and regardless of the fact that bolt B is either locked against extension or retraction from the casing the inner ends of said pins will be in abutment. Each pin has a head 21, a portion 28 extensible through the associated escutcheon l8, and an inner portion 29. Between portions 27 and 28 of said pins there are annular grooves 30, and between 28 and 29 thereof there are similar grooves 3!. Between each plate I! and the adjacent escutcheon 18 we provide an annular split tensioned ring 32 which is adapted to seat selectively in the grooves 30 and 3| of each pin for the purpose of holding said pins in inwardly or outwardly extended positions.

For instance, as shown in Fig. 1, the lefthand pin P' is illustrated as having been thrust inwardly through perforation 26 in member A for locking bolt B in extended position, while pin P is extended outwardly from the door on the right hand side thereof. Thus, door D is locked against accidental access to the room at the left of said door, but the extension of pin P from the right hand side indicates that the door of the adjacent room was intentionally locked and a person would ordinarily be deterred from ingress thereto. However, in an emergency, the thrust of pin P inwardly would project pin P outwardly from the opposite side of the door and when P is again retracted the bolt B will be released for retraction upon turning of the knob K in either direction, and permit ingress through the previously locked door to the room at the left of said door.

Pins P and P may also serve to lock bolt B in retracted position, as shown in Figs. 2 and 3, in which case said pins extend through the casing just forwardly of bar 25 on member A (see Fig. 3) following the retraction of the bolt by turning one of the knobs in either direction. In such event member A is directly actuated by cam C and by reason of its connection with the bolt, serves also to retract the bolt. Hence, under such a condition the bolt is not even efiective for latching the door in closed position until the then effective locking pin is released by the depression followed by a retraction of the other pin to remove it from the path of member A. When both pins P and P are in outward position, their inner ends will be separated and the member A will be free to move when either knob is turned.

Other advantages of our combined latch and lock will readily appear to users of indoor locks.

We claim:

1. A door latch comprising: a housing, a knob rotatable on the housing and a bolt formed of longitudinally alined members, operatively connected for retracting said members together upon the turning of the knob, but permitting the independent retraction of the latching member without turning the knob, and two transversely disposed, coaxially aligned, latching members operable from opposite sides of the housing and having their adjacent ends arranged for selective engagement with the bolt for locking the same in extended or retracted positions.

2. A door latch comprising: a housing, a bolt slidable therein to and from latching engagement relative to a stationary member, a knob carried by the housing; a cam in said housing rotated by said knob and an operating member slidable in the housing under the influence of said cam for retracting said bolt from latching position upon the turning of said knob, but permitting the free and relatively independent retraction of the bolt, and means normally urging the bolt to latching position, and separate coaxial locking members arranged on an axis paralleling the axis of the knob and having their inner ends abutting and operable from opposite sides of the housing for locking and unlocking the bolt in extended and retracted positions.

LAWRENCE L. ROSENTHAL. ROBERT E. SPENCER.

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

UNITED STATES PATENTS Fellows Mar. 23, 1943

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