Patent GB-609422-A (GB)
Title: Improvements in and relating to door latch mechanism
IPC: E05B65/32
Filed: 1946-03-13
Abstract: 609,422. Latches. ROETHEL ENGINEERING CORPORATION. March 13, 1946, No. 7908. Convention date, Oct. 26, 1945. [Class 44] A latch, particularly for vehicle doors, comprises a member rotatably mounted on a support, a longitudinally extending latch carried by the member and disposed at one side of its axis of rotation, detent means for locking the member in one or more latching positions, and spring means tending to return the member to unlatching position. The latch mechanism is mounted on a case-plate 25, Figs. 2 and 3, having a flange 26. The member 27 carrying the latch bolt 29 rotates on a stud 28. The bolt 29 projects through an arcuate slot 30 in the plate 25 and through a similar and registering slot in the jamb face 22 of the door. The plate 27 is formed on its periphery at the inner side of the pivot 28 with outwardly inclined abutments 31, 32 terminating in curved detent engaging shoulders. A detent arm 34 extending at its upper end in the plane of the plate 27 is riveted at 35 to one arm 36 of a bell-crank lever which pivots on a stud 37. The upper end of the arm 34 forms a dog engaging successively with the abutments 31, 32 on the plate 27 when the door is closed. The plate 27 is urged to unlocking position and the detent arm 34 urged towards the plate 27 by a common spring 40. In the unlocked position, shown in Fig. 6, the plate 27 abuts against a rubber buffer 33. The other arm 38 of the bell-crank lever carries a stud for one end of an operating cable 43 connected at its remote end to an inside handle, which may be of either the lever or the push-button type, and is also in contact with a plunger 110 operated by the outside handle. Additional means for securing the plate 27 in the latched position of Fig. 3 with the dog 34 in engagement with the abutment 32 comprise a locking lever 66, Fig. 4, pivoted at 67 to the case flange 26 to move in a plane at right angles to the plate 27, and having a part 66a which engages beneath the safety locking step 31 of the plate 27. The lever 66 is operated by a push-rod 71 extending through the garnish rail of the window. The part 66a also abuts against the upper part of the arm 36 of the bell-crank lever, thus preventing operation of the latter by the outside handle. A spring 73 yieldingly holds the lever 66 in either the locking or the unlocking position. The lever 66 may also be operable by a key lock connected to a shaft-83. The latch bolt 29 is actuated on closing the door by a striking plate 84, Fig. 12, having an inclined slot 86 to receive the bolt and move it and the plate 27 to latched position. The upper edge of the slot has a spring-pressed take-up slide 87, which is pressed back to the position shown by the bolt 29. A roller 92 on a fixed stud 91 on the door edge also engages the top edge of the striking plate. The external handle 99, Fig. 15, is of the pull-out type pivoting on a vertical pin 103, and its inner end lies within a housing 94, 95 and carries a stud 108 with a rounded head 110 making contact with the upper part 38a of the bell-crank arm 38, Fig. 3.