Door latch

Claim 1

In combination a warehouse type door having rollers riding in guide tracks installed to each vertical side of the door opening, for use in raising said door from a down closing position to an up open position, means for normally resisting downward movement of said door from its up open position, and a safety latch assembly affixed to said door adjacent a verticle edge thereof, said latch assembly comprising a mounting bracket, a latch pin, means on said bracket for slidably supporting said latch pin for movement towards said track from a nonlatching position with its latching end in proximity to the proximate edge of said door to a position with its latching end adapted to enter an aligned hole in the adjacent track, means normally biasing said latch pin toward its latching position whereby said latch pin will ride with its latching end in engagement with the adjacent track as said door is raised or lowered until it should align with a hole in said track, said track having such hole in line with said latch pin to receive said latch pin when said door in in its open position to function as a safety support for said door in the event of failure of said normal restraining means, said mounting bracket comprising a mounting plate and laterally extending mounting flange, a tubular member welded to the underside of said flange for slidably supporting said latch pin, a right angle component connected at its lower edge to said mounting plate and its upper edge to said flange to define a rectangular framework, a lever support arm affixed to a vertical section of said right angle component and having a free extremity, with the lower end of said lever arm pivotally connected to the free extremity of said lever support arm, said means normally biasing said latch pin toward its latching position including a spring anchored under tension at one end to said lever at an intermediate point thereof, and at its other end to said bracket, said lever terminating in a free end above said intermediate point and beyond the pivotal connection of its lower end, to permit of a downward motivating force to said lever to rotate said lever about said pivotal connection to withdraw said latch pin from its latched position.