Lock for sliding doors

Claim 1

A latch mechanism for a slidable door comprising: a hollow body, a latch plate having lip means adapted to releasably grasp a keeper, first pivot means pivotally supporting said latch plate within said body, a lever arm, second pivot means pivotally supporting said lever arm within said body, the axes of the two pivot means being spaced and substantially parallel, said latch plate being defined in part by a peripheral recess generally facing toward said second pivot means and receiving the distal end of said lever arm, said peripheral recess being shaped in such a manner as to form a cam and follower relationship with said distal end of the lever arm so that pivotal movement of said lever arm will cause pivotal movement of said latch plate between a keeper grasping, or latching, position and an unlatching position, said peripheral recess also being shaped such that when the latch plate is in its latching position the lever arm will be in contact with a planar portion thereof, the planar portion lying in a plane containing the axis of said first pivot means and being perpendicular to a second plane containing the axis of said second pivot means and the point of contact of the lever arm with said planar portion, so that all external pressure applied directly to said latch plate in an attempt to pivot it toward its unlatching position will be applied through said lever arm directly to said second pivot means, manually accessible means for pivoting said lever arm, and stop means fixedly carried within said body and limiting pivotal movement of said lever arm in one direction to that position wherein the distal end thereof abuts said planar portion of said peripheral recess of said latch plate.