Patent GB-1274929-A (GB)
Title: Latch
IPC: E05B65/32
Filed: 1969-08-08
Abstract: 1,274,929. Socks. ATWOOD VACUUM MACHINE CO. 8 Aug., 1969 [8 Aug., 1968], No. 39766/69. Heading E2A. A latch for a door comprises a base pivotally mounting a latching element, a detent member therefor and a locking lever, a pin connector moveable within an elongated slot in an actuating member between coupling and uncoupling positions with the detent member by the locking lever which has an elongated slot which receives the pin to move it therewith, the pin being in the uncoupling position with respect to the detent member when the locking lever is in the locking position, the actuating member then making an idle movement. The latching element 23 is pivoted between two plates and engages a keeper 24. The latching element has two teeth 66, 67, which are engageable respectively by a pivoted pawl 69 in the safety and fully latching positions. The pivoting actuating member 75 has the slot 97 in which moves the pin 87 and is supported thereby the pin engages beneath a lug 101 on the pawl to release the pawl from the latching element. The pivoted locking member 90 has the elongated slot 98 in which the pin 87 is also moveable whereby, on operating the locking member 90, the pin 87 is moved thereby along the slot to a position where the pin is out of engagement with the lug 101 and the actuting member 75 moves idly when actuated. The actuating members is operated from outside the door by a push button and from inside by a handle. The locking lever 90 is actuated from outside by a key and a link 95a and from inside by a sliding button. To prevent the door bursting open inadvertently, the latch element has a rib which engages a bead 43 on a base plate. On closing the door the striker 24 engages a plastics wedge 45 and urges it to move against a spring 47. The wedge is guided by a rib on the base plate engaging a groove in the wedge, also a tab 55 projects below the wedge into a slot in a flange 46. The tab engages a switch contact 57 to break the circuit of a warning light and thereby indicate that the door is closed. In a modification, Fig. 13, the locking lever 90' has a straight edge 105, which in the locking position, faces a lug 106 on the latching element 23' so that, when the door is closed, the lug 106 rotates the locking lever to its unlocking position thereby cancelling the locking action. For keyless locking, the outside push button is depressed to operate the actuating member, during closing of the door, and the locking lever 90' is moved to the locking position, the pin 87' is in register with a pocket 110 at one end of the locking lever slot 98' and the the lug 106 on the latching element rotates the locking lever to the unlocking position the edge of the pocket 110 engages the pin 87' and slides it to the uncoupling position. When the door is closed, the push button is released, and the actuating member 75 rotates under the action of a spring 86, the upper edge of the slot 97 therein engages the pin and presses it against an edge of the pocket causing the locking lever 90' to rotate to the locking position thereby moving the pin to the uncoupling position. The latching element may be unlocked by operating the inside handle by providing an additional lug on an inside operating lever.