GB231525A - Safety lock - Google Patents

Abstract

231,525. Chojecki, M. A. R. March 31, 1924, [Convention date]. Night-latches; lock-mechanism. operated by non-rotating keys; bolts; staples for locks. - A bolt has notched rear projections which co-opera.te with key-operated sliding notched pistons in the manner described in Specification 174,614, and the bolt nose has an outward bend so that, when released, it is retracted by the inclined staple on pushing the door from the outside. A catch normally holds the withdrawn bolt against shooting until released by slamming the door. The bolt may be two-part to allow inside handle operation when blocked by the sliders. The bolt comprises a rear part 10<1> provided with notched rods 11, 12, 13 co-acting with pistons 7<1> - - 7<6> which are urged by springs 16' - - 16‹ to bring their ends flush with the outside face of the casing 6 so that they engage the notches in the rods 11, 12, 13 and block the bolt against rearward movement. The front part of the bolt 10<2> has a bevel 22 directed towards the side opposite to that which is usual, and fits into the correspondingly inclined staple 23. A block 34 separates the parts. 10<1>, 10<2>, and the front part 10<2> is pushed outwards by the spring 31. To open the door from the outside, the key 8 is hooked round the pin Sa and pressed so that its projections 9' - - 9<6> push the pistons 7' - - 7<6> inwards so that their notches allow the rods 11, 12, 13 to slide backwardly. Pressure on the door then causes the inclined face 23 of the staple to force the bevelled bolt backwards, allowing the door to open. When the bolt has been forced backwards, a spring catch 26 pivoted in the casing 1 engages a notch 24 in the bolt-nose and holds it withdrawn until the door is slammed, when a projection 30 on the staple releases it and allows the bolt to shoot forward under the action of the springs 40, 31. To release the bolt from the inside, the handle 5 is turned and pulled. The turning movement causes a cam 38 on the handle, spindle 37 to depress the block 34 against its spring 36, and the pulling movement then retracts the front part 10<2> of the bolt against the spring 31 independently of the rear part 10'. The catch 26 operates as before. When the, door is opened from the outside, the block 34 slides with respect to the plate 35. To prevent the pistons from remaining in set position after operation by the key and retraction of the bolt and removal of the key, they are made in the parts 7<a>, 7b, so that when the rods 11, 12, 13 are holding the notched parts 7a in position, the parts 7b can return flush with the casing 6. Instead of a single bolt, two bolts rigidly connected by a strap carrying the rods may be used. If used for a drawer, the inside operating means is suppressed.