Patent GB-343810-A (GB)
Title: Improvements in and relating to door locks
IPC: E05B55/00
Filed: 1930-04-15
Abstract: 343,810. Door locks. SCHLAGE, W. R., 20, Bay Shore Avenue, San Francisco, U.S.A. April 15, 1930, No. 11880. [Class 44.] A door latch is provided with means for locking the outside handle against operation whilst leaving the inside handle free to withdraw the latch, the locking means being set at will so that it is automatically released when the latch is withdrawn (either by the inside handle or by key-operation from outside) or is held against such release. The latter setting allows the door to be slammed without releasing the locking means. A cylindrical casing 9 having an integral end 10 provided with a tubular extension forming a bearing for an inside handle spindle 15 has an outer removable coverplate 13 with an extension forming a bearing for the outside handle spindle 16. Fixed within the casing is a frame 18 guiding a slidable frame 20 having lugs 8 which embrace lugs 7 on the end of a bar 4 carried by the latch-bolt 3. The bolt is shot by a spring 6, and the slider 20 is urged towards shot position by a spring 23 bearing against one of a pair of internal lugs 22. The handle spindles 15, 16 are tubular with longitudinal slots 25 and with arcuate extensions 26 at their inner ends, the ends 27 of the extensions being reinforced as shown and bearing against the lugs 22, so that rotation of either handle in either direction withdraws bolt 3. Slidably guided in slots in the fixed plate 13 and thereby held against rotation is a locking bar 31 with lateral off-set 42, bar 31 passing through the inner handle spindle and terminating in a press-button 34 normally held projecting from the inner knob by a spring 39. When the button is pressed in to the position shown in Fig. 2 the part 42 enters slot 25 of the outer handle spindle and holds the outer handle against rotation. Bar 31 has an inclined projection 41 which, when the bar is pushed in, first displaces slider 20, the slider snapping back so that a part 21 thereof engages behind the projection as shown and retains the bar in its locking position. Bolt 3 may then be withdrawn by rotation of the inside handle, or by key from the outside, such withdrawal moving the part 21 to release projection 41 so that the locking bar is automatically released and moved to the left by its spring 39. Lugs, not shown, are also provided on the press-button, the lugs working in L-shaped slots so that the bar 31 may be retained in its inner position by a slight rotation of the press-button. To facilitate this rotation the button may have a rib, or, as shown, a slot 30 to receive the thumb-nail or edge of a coin. When so retained, bar 31 is not released automatically to free the outside handle when the latch is operated, so that the door may be slammed and entry obtained only by means of a key. The key-lock shown is of cylindrical type mounted within the outer handle and held against rotation by plungers 45 which are released on insertion of the key 46 used to rotate the cylinder. An extension of the cylinder carries a follower 48 acting on the lugs 22 to withdraw the latch-bolt 3. A spring 60 interposed between the end of the lock cylinder and a plunger 61 engaged by the end of bar 31 aids spring 39. Fig. 21 shows a modification in which a pivoted, non-rotating press-button 52 has a shoulder 53 engaging a projection 54 to retain bar 31 in locking position.