Patent GB-879377-A (GB)
Title: Improvements in or relating to safety locking devices
IPC: E05B83/36
Filed: 1958-05-27
Abstract: 879,377. Spring locks for vehicles. WENNER A. C., and TUTTELMANN, H. May 27, 1958 [June 8, 1957], No. 16855/58. Class 44. A lock, e.g. for a motor coach, comprises a follower 7 which is rotatably mounted between base and cover plates 6, 3 respectively of a lock casing and is attached by pins 10, 11 to door handles 12, 13, a spring, not shown, constrained between a ledge on the casing and one end of a rod 16 pivoted at 15 to an extension 14 of the follower 7, urging the latter into the locking position shown in Fig. 1. A finger 19 on the follower 7 engages in a recess 18 in a slidable spring bolt 17 having a U-shaped opening 20 which embraces a cylindrical portion of the follower 7 to guide and locate the latter. The finger 19 coacts with shoulders 21, 22, on the bolt when the handles 12, 13 are respectively pressed downward, or lifted, to shoot or retract the bolt 17. A catch 25, pivoted at 24 on the base plate 6, has an extension 26 which engages behind the bolt 17 when the latter is in shot position. A slidably displaceable locking member 28, which coacts with an upstanding projection on the catch 25 to dead lock the bolt, is mounted upon a laterally movable pin 29 having its ends engaged respectively in a slot 30 in the cover plate and in a recess 32 ih an outside facing plate 33. The spring-loaded plunger 34 of a dash-pot 36 bears against the adjacent end face of the locking member 28. Movement is imparted to the pin 29 by means of levers 41, on the ends of a shaft 42 carrying two forked levers 45, 46, which engage the pin 29. Before the lock can be opened by the handle 12, or 13, (e.g. the outside) lever 41 must be moved in a clockwise direction from the position shown in Fig. 1 to displace the locking member 28 into an inoperative position against the action of the spring- loaded plunger 34 of the dash-pot 36. Operation of a handle now retracts the bolt 17 which, as it sides in the casing, raises the catch 25 so that a projection thereon moves into the path of the locking member 28 to prevent the latter from being returned into its operative position by the plunger 34. When the door is closed and the bolt is returned into the position shown in Fig. 1, the catch drops back behind the bolt 17 however, the dash-pot plunger 34 does not immediately return the locking member 28 to dead lock the bolt so that the door can be opened repeatedly in succession for a short period before the locking member returns to its dead-locking position. In a modification, Fig. 5, a crank-type inside door handle 47 carries a releasable coupling which is engageable with a coupling rod 57 fixed to the pins 10, 11 for actuating the bolt 17. The hub 49 of the handle carries an axially movable but non-rotatable coupling member 52 having a push-button extension 53 and engageable with the coupling rod 57 against the action of a dash-pot which is similar to the dash-pot 36 and is accommodated in the coupling rod 57. A further modification describes an alternative method of coupling the door handles with the lock action with the interposition of a dash-pot such as 36.