GB633018A - Improvements in or relating to door lock structures - Google Patents

Abstract

633,018. Door latches. HOUDAILLE-HERSHEY CORPORATION. Aug. 12, 1947, No. 22365. Convention date, Sept. 27, 1946. [Class 44] In a door latch the outside handle operates a lever 11, Fig. 1, adapted to contact and rotate a second lever 16 to release the bolt, the second lever 16 being movable by a number of different methods to a position in which it cannot be contacted by the lever 11 thus rendering the outside handle ineffective. The latch 26 is carried on a pivoted plate 24 which in the locked position also supports the free end 51 of a serrated lever 49, Fig. 2, co-operating with an arm 45 adapted to retain a rotor bolt 39, Fig. 5, in an angular position to engage the keeper K, the position of engagement depending on the force with which the door is slammed. In a normal unlatching operation the lever 11 contacts a projection 17 on the second lever 16 to rotate it in an anticlockwise direction, the nose 25 contacting an arm 24a on the plate 24, rotating it in a clockwise direction to lift the latch 26 and release the arm 45 retaining the rotor bolt. An inside handle 62 is connected through an arm 102 and a link 20 to turn the lever 16 in an anti-clockwise direction to release the latch or in a clockwise direction to render the outside handle ineffective by disposing the projection 17 out of the path of the lever 11. The inside handle-62 is provided with a centring spring 104 to return the handle to the normal position, the lost motion in a pin and slot connection to the lever 16 ensuring that the centring movement is not transmitted to the lever 16. A push rod 65 operated by a button on the inside of the door may be depressed to rotate the lever 16 in a clockwise direction and this mechanism may be used to lock the door from the outside by closing the door with the outside handle turned and then releasing the handle. Rotation of the outside handle when the lever 16 is in the locking position places the lever 11 behind the projection 17. The lever 16 is returned to the unlocking position as the door closes by the engagement between the latch 26 and the keeper. When the outside handle is released after the door is closed, the spring 14 on the lever 11 again moves the lever 16 to the locking position in which the outside handle is ineffective. A key operated lever 29 has arms 31, 32 embracing a projection 21 whereby the lever 16 may be moved to and from the locking position from the outside. This lever is retained in either position by a spring 34b engaging in one of two notches 36, 37 and thus serves to retain the lever 16 in the locking or unlocking position.