GB339843A - Improvements in and relating to door knob locking devices - Google Patents

Abstract

339,843. Ellingson, E. Jan. 21, 1930. Night latches; latches, preventing operation of.-A rod sliding in a recess in the knob spindle can block the catch, render both knobs inoperative or render the outside knob inoperative. The rod 51 slides in the recess 19 in the spindle 14 and carries a latch-blocking projection 54 and a projection 53 which can engage a recess 44 in the rose-plate 28 of the outside handle 37 to render the spindle non-rotatable. The end of the rod is secured to a member 41 which couples the outside knob to the spindle 14 by engaging a recess 50 therein. When the rod is pushed fully inwards, the member 41 is clear of the spindle and legs 43 on it are held in recesses in the rose-plate. Fig. 2 shows the device in the unlocked position, the knobs being turnable to retract the latch bolt 2, by the follower 12, the shank 7' of the bolt entering between the lugs 54, 53. If the rod 51 is pushed in by the button 52 or pulled in by the cylinder lock 38', the projection 54 blocks the latch, and the projection 53 and legs 43 enter the recesses in the roseplate. If the rod is half pushed in, the projection 54 is moved so that the inclined part 56 is opposite the latch, but the legs 43 are in the recesses in the rose-plate. Operation by the outside knob is impossible without first turning the key, in this position, but operation by the inside handle restores the rod to full unlocking position.