GB1148892A - Improvements in and relating to latches - Google Patents

Abstract

1,148,892. Latches. J. LEGGE & CO. Ltd. 8 July, 1966 [14 July, 1965], No. 29771/65. Heading E2A. A latch includes a housing 17, a latch lath 10 contained within said housing, said lath having a nose 11, spring means 31 acting on said lath to urge it into a position in which the nose projects from the housing for engagement with a keeper and means for effecting retraction of the lath, comprising a plunger 12 movable manually in a direction transverse to the direction of movement of the lath, a first link 15 pivoted to the housing, a second link 20 pivoted to the lath and to said first link and a bearing surface on one of the links, an end of said plunger being arranged to abut said bearing surface whereby manual movement of the plunger towards the lath serves to extend the link system, thereby retracting the lath against the action of the spring means. In the construction shown the housing is intended for attachment to the inner face of a door and' the plunger extends through the door and carries a button 13 which is accessible from the outside of the door, the button being slidable in an aperture formed in a handle assembly 23 which is disposed on the outside of the door and includes a gripping portion 24. Outward movemenu of the plunger is prevented by a collar 21a. The handle assembly is contained in a plastics dish 25 fitted in a well 26 in the outside of the door. The handle assembly also includes a key operated cylinder lock 27 having a bolt 28 which is movable along a guideway into a position in which the bolt 28 is in the path of movement of the collar 21a on the plunger and thus when the lock 27 is operated, movement of the plunger is prevented and hence retraction of the latch lath 10. The latch lath 10 is formed as a metal pressing and' the end portion remote from the nose 11 is secured to an end cap 30 by which the latch lath can be moved from the inside of the door. The end cap 30 is slidable along the edges of a front plate 19 of the housing, the housing also including a channel section body portion 18 fixed to the plate 19 by the free ends of the arms of the channel. The body portion 18 contains the latch lath 10 and the links 15, 20 and as shown it is the link 15 which has the bearing surface engaged by the plunger. Retraction of the lath is preventable by means of a snib 35 disposed on the inside of the door and arranged to pass through aligned apertures 36 in the housing; the snib 35 is arranged for movement in a direction normal to the directions of movement of both the lath 10 and plunger 12 and has an abutment 37 which in one position is in the path of movement of a projection 34 on the lath 10 to prevent movement of the bolt and in another position allows such movement; the travel of the snib is limited by engagement. of a projection on the snib with abutments on the latch housing assembly. The sirub 35 is retained in its release and its locking positions by a spring of generally hair pin shape which is engageable with a pair of formations of .the snib. The snib holds the latch lath in both the fastening and unfastening positions.