Patent GB-1217586-A (GB)
Title: Latch mechanism
IPC: E05C9/04
Filed: 1968-04-09
Abstract: 1,217,586. Door fastenings. FORD MOTOR CO. Ltd. 9 April, 1968 [13 April, 1967], No. 17020/68. Heading E2A. A latch mechanism for a door 10, comprises a support plate 19 for mounting on a door a pair of oppositely extending bolts 66 for engaging with keeper devices in a door frame, retractor means pivotally mounted on the support plate for movement in either of two directions, spring means 56 positioned adjacent the retractor means, said retractor means being coupled to the bolts for causing retraction of the latter to door releasing positions upon pivotal movement of retractor means in one direction, said retractor means upon being pivotally moved in the opposite direction causing, each bolt to project further in a direction away from said retractor means, wherein in use on a door, each bolt projects bevond the edge wall of the door in an open position of the door so that when the door is slammed shut, the engagemnt of the bolts with the keeper devices will cause the retractor means to wind up the spring means, and upon further movement towards a door closed position, the spring means acts upon the retractor means which acts upon the bolts to restore the bolts and retractor means to normal keeper engaging positions. In the construction shown, housing 24 secured to the plate 19. The retractor means consists of a shaft 28, a handle 42 secured to one end portion of the shaft and two levers 44, 45; the shaft is supported by the plate 19, and the housing 24 and includes a shoulder 33 having parallel flats 34, the levers each having a circular plate portion with a centrally located aperture 47 adapted to fit over the flatted shoulder 33 of the shaft. Each lever also has a radial extension 48 and a lateral appendage 51. The apertures 47 in the, levers are in part complementary to the flatted shoulder 33 of the shaft but are provided with diametrically laterally offset edge portions 52 so that the levers can move independently of the shaft to a limited extent. Each lever is connected by a link rod 65 to a respective bolt 66 and the spring 56 is supported on an elongated pin 57 that extends between tabs 58, 59 of the housing 24, elongated end leg portions 61, 62 of the spring projecting through slots in the housing 24 and each overlying one of the levers 44 and 45 so that when the levers are holding the bolts in the retracted positions, the springs are biasing the levers and hence the bolts towards the latching positions. The shaft 28 also has a flange 35 which has a pair of spaced V-shaped indentations 36 and 37 engageable by a detent pin which is biased by a spring in the direction of the indentations; the pin, when engaging the indentation 36 holds the shaft and hence the bolts in the position in which the bolts are in latching engagement with their keeper devices; movement of the shaft 28 in a clockwise direction from this position will move the levers clockwise and this urges the bolts into the deeper keeper device engagement, the bolts being held in this position by the pin engaging the indentation 37; to release the door the shaft is turned counterclockwise by the handle and the initial movement of the handle only has to overcome the force of the spring holding the pin in the indentation 37, since when the bolts are in deeper engagement with the keeper devices, the end partions of the spring 56 are out of engagement with the levers 44 and 45; continued movement of the shaft forces the levers to pick up the end portions of the spring 56 and winds up the spring; as soon as the door is opened and the handle released the spring moves the bolts outwardly so that when the door is slammed shut it will remain shut. The free movement of the levers relative to the shaft 56 enables the bolts to move during the slamming of the door without moving the shaft and handle.