Patent GB-1160601-A (GB)
Title: Closure Latch
IPC: E05B65/32
Filed: 1967-07-06
Abstract: 1,160,601. Latch fastenings. GENERAL MOTORS CORP. 6 July, 1967 [18 July, 1966], No. 31105/67. Heading E2A. A closure latch comprises a bolt 22 mounted on a support 18 for movement between intermediate and full latching positions, a detent 62, 64 for each latching position including a foot 68, 70 engageable with the bolt to hold the bolt in the respective latching position and an arm 82, 88 engageable with a common stop 84 mounted on the support to locate the detent members in holding positions against the action of resilient means 76 biassing the detent members to holding positions. In the construction shown the bolt 22 is of the fork type and is pivoted on a shouldered stud 24 extending between the support 18 and an auxiliary plate 26 which is staked adjacent its upper edge to a lateral flange 30 of support 18 and which includes a lower lateral flange 32 which terminates in an offset flange 34 staked to the support 18. On each side of the flange 32 are lateral flanges 40 which support a pin 42 on which a wedge shaped nylon shoe 44 slides, the shoe being biassed outwardly of the latch i.e. to the right as shown, by a coil compression spring surrounding pin 42. The bolt, in both the intermediate and full latching positions, receives a shank 50 of a headed striker pin 52 in its throat 48. The head of the striker pin engages the shoe 44 so that the pin is trapped between the bolt 42 and the shoe 44. The support 18 is cut away to permit the entry of the striker pin into the bolt. The bolt is biassed towards the unlatching position by a coil torsion spring 58 which surrounds the stud 24 and has one end portion hooked to a pin 60 secured to the bolt and the other end portion hooked to a lateral notched tab of support 18. The detents 62, 64 are co-axially mounted on a shouldered stud 66 secured to the support 18 and the feet 68 and 70 are part of a first arm of each detent. The feet 68 and 70 are selectively and alternatively engageable with respective spaced abutment shoulders 72, 74 of the bolt 22 to hold the bolt in either the full latching or intermediate latching positions. The means 76 is a spring of the coil torsion type and surrounds the stud 66 and has one end portion engaging one side of a lateral flange of an offset arm 78 of detent 64 and the other end portion engaging a lateral flange of an offset arm 80 of the detent 62 to bias the detent members oppositely of each other towards the bolt 22; the stop 84 is a resilient bumper mounted on the lateral tab 86 of support 18. A shaft 90 extends the full length of the support 18 between the upper flange 30 and a lower flange 92 and the support 18 and mounts an outside operating member 94 which can both pivot and shift longitudinally of the shaft member 94 and is biassed in a clockwise direction as viewed in Fig. 2 by a tension spring 100. In its inoperative position is held against the bias of the spring by the engagement of a flange 104 with an arm 80 of detent member 62. Member 94 is moved to release the detent members from the bolt by a push rod (not shown) which is operated by a push button incorporated in an outside handle, the push rod being engageable with the member 94 anywhere along its length. The detent 62 is moved to release the bolt by the engagement of an upwardly extending arm 114 of the detent by an offset foot 112 of the member 94; the detent 64 is moved to release the bolt by the engagement of a lateral tab 136 of the member 94 with an arm 78 of the detent 64. The member 94 is moved longitudinally of the shaft 90 between the locking and unlocking positions by an inside locking lever 118 pivotally mounted on the plate 26; ,the locking lever 118 is forked and engages a downwardly offset foot 116 of the member 94. The locking lever is moved between locking and unlocking positions in both of which it is held by an overcentre coil torsion spring 122 by a forked inside operating lever 124 which is pivoted to a lateral flange of the plate 26 and straddles the foot 130 of the locking lever. The lever 124 is connected by a rod and lever arrangement with a garnish button. When the locking lever 118 is in its unlocking position, the foot 112 of a lever 94 is located in the path of the arm 114 of detent 62 and the tab 136 is located in the path of the arm 78 of the detent 64 so that movement of the member 94 by the push rod 106 withdraws the detents from the bolt so release the bolt. When the locking lever is in the locking position the foot 112 swings above the arm 114 of detent 62 without engaging it and the tab 136 swings above the arm 78 without engaging it; the bolt thus remains held by either of the detents. The member 94 can also be pivoted by an inside remote handle which is connected to the member 94 via an inside operating lever 148 pivoted to the flange 92 of support 18 the lever 148 being engageable with a depending foot 152 of member 94. The bolt is moved from its unlatching position to either latching position by engagement with the shank 50 of pin 52. If the door to which the latch is attached is slammed closed with the locking lever 118 in its locking position it is automatically undogged by an arm 80 of the detent 62, since the detent is moved by engagement of its foot 68 with the shoulder 72 of the bolt the arm 80 of the detent engaging a tab 154 of the member 94 to shift the member from its locking to its unlocking position; automating undogging cannot occur when the bolt moves only to the intermediate latching position. Keyless locking is accomplished by holding the push button depressed during closing movement of the door which moves the tab 154 underneath the arm 80 of detent 62 so that there is no engagement between the arm 80 and tab 154.