Patent GB-853931-A (GB)
Title: Motor vehicle door latch
IPC: E05B65/34
Filed: 1958-12-12
Abstract: 853,931. Latch fastenings. GENERAL MOTORS CORPORATION. Dec. 12, 1958 [Dec. 23, 1957], No. 40136/58. Class 44. A motor vehicle door latch comprises a rotatable latch bolt 300, Fig. 5, under the control of a pawl lever 310 and ratchet wheel 308, the lever 310 being withdrawable from engagement with the ratchet wheel 308 by an operating lever 324 pivoted to a link 336 which in one position on its pivot transmits the movement of the operating lever 324 to the pawl lever 310 and in another position on its pivot moves idly when the operating lever 324 moves, and in which an unlatching lever 350, Fig. 2, operable by an inside door handle (not shown) has alternative connections to the pawl lever 310, the one connection through the operating lever 324 and the link 336 and the other through a connection which by-passes the operating lever 324 and the link 336. The bolt 300 is in the form of a gear rigidly connected to a stud 302 rotatably mounted in an angle section frame 304 and in a bolt housing 306 and the stud 302 carries the ratchet wheel 308 which is positioned on the inner side of the frame 304, the pawl lever 310, which is pivoted, being spring-urged into engagement with the wheel 308. The link 336 is moved to each of its positions on its pivot by a pivoted bell-crank locking lever 340 connected by a rod 50 to a garnish moulding button (not shown), the locking lever 340 having a slot 346 which engages a bent end 348 of the link 336; when the link 336 is in its one position and the operating lever 324, which is spring- loaded and is pivotally mounted at 326, is moved by a rod 122 of an outside push-button assembly (not shown) the pawl lever 310 is disengaged from the ratchet wheel 308 and when the link 336 is in its other position its movement is ineffective and consequently the pawl lever 310 cannot be disengaged by operation of the outside push-button. By movement of the garnish moulding button to lock the door against opening by operation of the outside push-button and depending upon how the unlatching lever 350 is connected to the pawl lever 310, the door is or is not openable by the inside door handle. The unlatching lever 350 is pivoted at 352 and is connected to the inside door handle by a rod 44 and pivoted on the unlatching lever 350 is a selector lever 354 which is movable between two positions and has a slot 358 for co-operation with a tab 360 bent from the unlatching lever 350, to limit movement of the selector lever 354 relative to the unlatching lever 350. An overcentre spring 362 is disposed between the levers 354 and 350 to yieldably hold the selector lever 354 in each of its positions. With the selector lever 354 in the position shown in Fig. 2, operation of the inside door handle moves a pivoted actuator lever 372, giving the one connection of the unlatching lever 350 to the pawl lever 310, and if the link 336 is in its position in which is movement is ineffective, the door is locked against opening by operation of the inside door handle. When the selector lever 354 is moved clockwise to its other position, Fig. 3 (not shown), operation of the inside door handle moves, instead of the lever 372, another pivoted actuator lever 367, giving the other connection of the unlatching lever 350 to the pawl lever 310, in consequence of which the door is opened. The selector lever 354 may be in either of its positions prior to the assembly of the latch in the door and an opening may be made in the door for the insertion of a tool for moving the selector lever 354.