Patent GB-1100361-A (GB)
Title: Vehicle door latch
IPC: E05B65/32
Filed: 1965-05-04
Abstract: 1,100,361. Latch fastenings. L. W. MENZIMER. 4, May, 1965 [27, July, 1964], No. 18624/65. Heading E2A. A door latch comprises a support, a latching member 23 rotatably mounted on said support to turn between latching and unlatching positions, mechanism selectively operable to hold said latching member in the latching position and to release the member for turning to the unlatching position, a locking member 53 mounted on said support to move between, locking and unlocking positions and operable in the locking position to maintain the latching member in the latching position, and operable when in the unlocking position to permit release of the latching member, said mechanism including movable detent means 77 operable when said latching member is in the unlatching position to stop said locking member in an intermediate position las the locking member is moved away from the unlocking position, a first manual element (e.g. a garnish moulding button operable to move said locking memiber away from the unlocking position and against the detent means and a second manual element) a push button subsequently operable to displace said detent means and release said locking member for movement to the locking position whereby the sequential operation of said elements places the latch in a locking condition. In the construction shown the latching member is a rotary member keyed to a shaft 21 and formed with two, gear teeth 24 and 25 which coact with a striker (not shown); the latching member is on one side of a leg 33 of an L shaped brackat 34 forming the support and on the other side is a ratchet 39. The mechanism operable to hold said latching member in the latching position comprises a pawl 31, on a shaft 36, which is engageable with either of two teeth of the ratchet, one of which holds the latching member in the full latching position. and the other in a safety latching position; a spring 41 biases the pawl and the ratchet into engagement. Mounted on the shaft36 by means of a slot 50 is a contactor 46 and in the unlocking condition of the latch an arm 56 of the contactor engages an arcuate surface of the locking member 53 so that the contactor is compelled to pivot on the shaft 36; the pivoting movement of the shaft caused by the push button then moves the pawl 31 so that the ratchet is released. This happens because the pawl is provided wih a slot 48 which is eccentrically positioned in relation to the axis of the shaft 36 and the slot is engaged by a pin 47 carried (by the contactor; the eccentric arrangement of the slot prevents the pin moving out of the slot. When the locking lever 53 is in the locking position in which it does not contact the arm 56 the contactor slides relative to the shaft 36 because of the slot 50 and this enables the pin to move relative to the slot so that the pawl 31 does not move. The locking lever is moved by an arm 66 on a key controlled shaft 65 or by a link 68 firom the garnish moulding button or by an interior handle through a link 69 and a lever 71, the lever having an arm 70 which is engageable with the locking lever. The lever also has a second arm 74 and upon movement of the interior handle in the opposite direction this also engages the locking lever and swings it in the opposite direction to unlocking position. The arm 74 also engages a laterally offset extension 75 of the pawl 31 to swing the pawl out of engagement with the ratchet 32. The sequential manual operations referred to above enable the door to be locked from the outside without using the key; when the garnish moulding button 64 is depressed the locking lever is moved towards the locking position by the link 68 but it is stopped in the intermediate position by the detent means 77 which is a finger projecting from an arm 49 of the pawl 31; the detent means 77 is in a suitable position when the door is open, since the tooth 37 of the pawl albuts a surface 78 of the ratchet 32 and holds the pawl in a position intermediate its two extreme positions; the detent means 77 engages an ear 79 projecting laterally from the upper arm 55 of the locking lever 53. The second manual operation, the depressing of the push button, turns the contactor 46 counterclockwise this being possible since an edge of the contactor is blocked by a lobe 81 of the ratchet 32; hence the contactor through the pin and slot connection takes the pawl with it and the detent means 77 is moved below the ear 79 so that the locking lever, under the urge of a spring 58, continues its movement towards the locking position until it comes up against the extension 75 on the pawl. Closing the door then turns the latching member 23 and hence the ratchet 32 back to the latching position and this permits the pawl 31 to move its extension 75 into a notch 82 in the locking lever to permit the lever to move to its locking position. If the door is closed after the garnish moulding button has been depressed and before the push button has been depressed the locking lever 53 is returned to the unlocking position by the upper edge 83 of the detent means 77 which acts as a cam and coacts with a follower 84 of the locking lever.