Patent GB-900677-A (GB)
Title: Door control mechanism
IPC: E05B65/32
Filed: 1960-03-28
Abstract: 900,677. Latch fastenings. MENZIMER, L. W. March 28, 1960 [Dec. 3, 1959], No. 10829/60. Class 44. Door control mechanism comprises a support 57 for mounting on a door, latch means pivoted on said support and movable to and from a door latched position, detent means 65 effective on said latch means for releasably retaining the latter in said door latched position and including a swingable first arm 69, a detent release member 66 pivoted on said support and including a swingable second arm 72 adjacent said first arm, a locking member 81 shiftably mounted on said support for movement to locking and unlocking positions and control means 78 connected with said locking member and having a control portion 79 extending transversely to one of said arms, said control means being shiftable by said locking member for moving said control portion to effective and ineffective control positions, said detent release member having an idle movement relative to said detent means when said control portion is in said ineffective position and the other of said arms being engageable with said control portion when the latter is in said effective position for rendering said detent means actuatable by said detent release member. In the construction shown, the latch means comprises a latch member 29 which is fixed to a shaft 27 by which it is pivoted to a plate portion 58 of the support 57, a ratchet member 63 being fixed'to the shaft 27 on the opposite side of the plate portion 58 to the latch member. In addition, the shaft 27 pivotally supports a roller 30 immediately adjacent the latch member and on the outer side of it, the roller being retained by a projecting bracket arm 31. The latch member and roller co-operate with a keeper 14 which consists of a hollow body 34 haying a recess 35 presented towards the edge wall 23 of a door frame to which the keeper is secured and which recess receives the roller 30 when the door is moved to its closed position. The keeper has a notch 38 in its front wall 37 to accommodate the shaft 27 when the door is moved to its closed position and in the front wall 37 below the notch 38 is a pocket 44 which receives one of the teeth 32a of the latch member in the latching position. The engagement of the roller with the keeper corrects any misalignment when the door is closed and also prevents spreading apart of the door and door frame in the fore-and-aft direction. The keeper is also provided with a pocket 52 in which is a swingably-mounted wedge-member 53 which is engaged by the roller to support the door and also urge the latching tooth 32a of the latch member downwardly into the pocket 44. In the construction shown, the latch member has two teeth, 32a, 32b, and the ratchet member has three teeth 63a, 63b and 63c with which the detent means 65 co-operates for holding the latch member in different positions. When the tooth 63a is engaged by the detent means the latch member 29 is in its door latched position ; when the tooth 63b is engaged by the detent means the latch member 29 is in its safety latched position in which the tooth 32a extends only partly into the pocket 44; when the tooth 63c is engaged with the detent means the latch member is in its door unlatched position. The control means 78 is a T-shaped member having a stem portion 78a which is loosely and slidably received in an opening 91 of a bracket 85 which is rigidly fixed to the locking member 81; the bar portion of the control means includes the control portion 79 and is slidably supported between the arm 69 and a bracket 84 which is attached to the arm; thus the control means can be moved transversely of the arm 69 into the path of movement of the arm 72 by swinging the locking member. When the control portion is in the path of movement of the arm 72 swing- ing the detent release member also swings the detent means and hence releases the ratchet member so that the latch member can rotate in an unlatching direction to release the door. This release movement of the detent release member is accomplished by a push-button from the outside of the door, the push-button shaft 73 engaging a flange 71a of an actuator arm 71 of the release lever. It can also be accomplished from the inside of the door by means of a handle connected through a link 109 with an unlocking lever 104 pivoted on a flange portion 59 of the support; this engages the bracket 84 to pivot the detent means 65 to unlatching position. The locking member 81 is swung from locking to unlocking positions and vice versa from the outside of the door by a cylinder lock which rotates a locking finger 99, the free end of which is received in a C-shape opening of the locking lever. In addition the locking lever is moved from the inside of the door by a pushpull link 106 which extends adjacent the garnish moulding of the door and is moved by a knob. Should the locking lever be in its locking position when the inside handle is operated to unlatch the door, the end of the unlocking lever 104 engages a cam portion 93 of the locking lever 81 and swings the latter to its unlocking position. When the lever 81 is in its locking position in addition to moving the control means 78 to enable the detent release member to move freely without actuating the detent means the control member 81 has a shoulder 94 which in the locking position is located immediately below the arm 84a of the bracket 84 to prevent downward swinging of the arm 69 and hence release of the latch member. If an attempt is made to lock the latch means while the mechanism is in its door unlatched condition the swinging movement of the locking lever causes the shoulder 94 to press against the support arm 84a and thus prevent locking. The locking member is connected to the support flange 59 by an over-centre type spring 114; the support flange 59 is provided with a C-shaped opening and the end 115 of the spring can be engaged with either end of the opening; when it is in the right-hand end 119 the spring always tends to swing the locking lever towards its unlocking position and consequently slamming the door can never cause the mechanism to assume the locked condition. When the spring end is in the left-hand end 120 the action of the spring is to produce swinging of the locking lever towards the locking position and under these conditions slamming door will cause the mechanism to assume the locked condition provided the shoulder 94 is in engagement with the support arm 84a when the door is open. In a modified embodiment the latch member is provided with five teeth spaced equally around its circumference and any one of these can engage the pocket 44; the latch member has five deep teeth and five shallow teeth, the shallow teeth providing the safety latched condition and the deep teeth the fully latched condition. The control means 78 is carried by the detent release lever instead of by the detent means and consequently the bracket 84 is connected to the detent release lever. The stop 94 is omitted from the locking lever and the spring 114 always tends to move the locking lever to its unlocking position.