Patent GB-697144-A (GB)
Title: Door control mechanism
IPC: E05B65/32
Filed: 1951-10-15
Abstract: 697,144. Latches and locks. SCHONITZER, R. I. Oct. 15, 1951 [Dec. 28, 1950], No. 23990/51. Class 44 Door latch mechanism comprises a rotary toothed latch device L, Fig. 1, mounted on a plate portion 8 of the support, an actuating lever A pivotally mounted intermediate its ends on the plate portion, detent means D engageable with the latch for holding it in latching position, this detent being pivoted on the plate to swing independently of the actuating lever A. The lever A is provided with a part 28 arranged opposite a part 16 of the detent to abut on the same side of the pivotal axes of the actuating lever and of the detent D, so that on swinging movement of the actuating lever in one direction the detent is swung in the same direction to release the latch. The support for the mechanism comprises a base plate 8 and a side flange 9. Mounted on plate 8 is the toothed rotary latch L, comprising a shaft 11, teeth 12, and a ratchet element R with teeth 13 on the inner end of the shaft 11. A spring urged detent member D is mounted on plate 8 and comprises a downwardly extending arm 15, the end of which engages the ratchet teeth 13, and a transverse arm 16. The actuating lever A is pivotally mounted on the same pin as the detent D, and has an upwardly extending portion 22, with a flange to be engaged by the push button plunger 24, and a transversely extending arm 27 offset inwardly at 28 with an end portion 29 projecting through a slot in the side flange 9, the offset part lying above the transverse arm 16 of the detent D. A spring 18 which urges detent D in clockwise direction as seen in Fig. 1 thus urges lever A in the same direction, and operation of the push button 25 releases the detent from the teeth of the ratchet element R. On closing the door, the teeth 14, 14<SP>1</SP>, Fig. 5, of the keeper K engage the latch L and rotate it, and the arm 15 of the detent D rides over the ratchet teeth 13. The two teeth 14, 14<SP>1</SP>, provide respectively a safety position and a fully closed position of the door. A tapered blocking member 31, Fig. 5, mounted on the plate 8 engages at once the upper surface of the keeper and a sliding spring-urged wedge 32 mounted on the keeper. A locking member B, Fig. 2, is pivoted on a pin 36 on the side plate 9. The upwardly extending arm 37 has a blocking abutment 38 which when the member B is in the locking position shown, is located below the end part 29 of the lever A, preventing movement in releasing direction. The upper end of the arm 37 in provided with a cam face 39, and the downwardly extending portion is connected to the push rod 41 for interior operation; lifting the knob 42 moves member B to unlocked position. The locking member B can also be actuated from outside .by the key lock mechanism M, Fig. ], which is connected by a shaft 43 to an arm 44 by which member B is moved to locked or unlocked position. The clearance between the arm 44 and the member B is such that the latter may be moved from one position to the other by either the key lock or the push-button regardless of the position in which it is set by the other. The member B is held in either position by a snapover spring 47. The locking member is formed with a shoulder 50 which extends towards the base plate 8 and overlies a slot in the flange 9. The outer end 16<SP>1</SP>, Fig. 7, of the arm of detent D lies above and spaced from shoulder 50 if member B is placed in locking position with the door. open. If now the door is closed, the rotation of ratchet R will cause the arm 16 of detent member D to move downwardly and swing locking member B to the unlocked position by contact with shoulder 50. An inside remote control means is provided in the form of bell-crank C, Figs. 2 and 7, connected by a control strap 63 to an inside handle or button, and having a part 54 which moves member B to unlocked position by contact with a cam face 39 thereon, and then engages the end portion 29 of actuating lever A to release the detent D. In a modification, the bell crank C does not move locking member B from locked to unlocked position, and will only release the latch if member B is in unlocked position. In another modification, Fig. 12, the lock number B" is cut away at 56 so that the end 16<SP>1</SP> of the detent member does not strike it during closing movement of the door, and member B, if then in locked position, remains so. A modified form of mechanism is shown in Figs. 13 and 14, where R<SP>1</SP> is the ratchet element, A<SP>1</SP> the actuating lever, and D<SP>1</SP> the detent member, the edge 69 of a downwardly extending part of which is engaged by a flange 62 on the arm 60 of lever A<SP>1</SP>. The lock member E is pivoted to the side flange 58 of the support, and has an upwardly extending arm 71 with a blocking abutment 72 which in the locking position of member E lies in the path of the end part 64 of lever A<SP>1</SP>.