Latch assembly having pull-up action

A latch having a pull-up action for developing a compressive force between a movable door and a fixed cabinet, said latch comprising:

• a. a shaft adapted to project through an opening in a door;
• b. a latch body fixed mounted on said door adjacent said opening for supporting said shaft for axial and angular movement;
• c. a latching pawl carried by said shaft;
• d. a handle supported on an end portion of said shaft;
• e. an annular cam carried by said handle, said cam having a surface having at least two peaks, at least two low seats, and sloping surfaces therebetween;
• f. a cam-follower pin secured to and projecting laterally in both directions from said shaft;
• g. means biasing said shaft axially for maintaining opposite ends of said cam-follower pin in engagement with said cam surfaces;
• h. a motion-control pin mounted in fixed position on, and projecting laterally in both directions from, said shaft;
• i. motion-control slots positioned axially in said latch body for receiving opposite ends of said motion-control pin for preventing angular movement of said shaft when ends of said control pin are within said motion-control axial slots;
• j. motion-control recesses positioned angularly in said latch body for receiving said opposite ends of said motion-control pin and for preventing axial movement of said shaft when said ends of said control pin are within said recesses;
• and
• k. each of said motion-control slots and motion-control recesses intersecting, each of said slots having a sidewall which projects into its intersection and defines one end of one of said recesses, said sidewall functioning as a stop for angular movement of said control pin in said recess.

A latch having a pull-up action for developing a compressive force between a movable door member and a fixed member, said latch comprising:

• a. a latch body adapted for non-rotatable mounting on one of said members, said latch body having a generally cylindrical bore substantially perpendicular to the surface of said one member;
• b. a handle mounted for rotation at an outer end of said latch body, said handle having a generally cylindrical bore coaxial with said bore of said latch body;
• c. a shaft disposed within and coaxial with said bore of said latch body and said bore of said handle, said shaft extending beyond said latch body;
• d. means provided on one end of said shaft to engage said one member when said shaft is at a predetermined position of rotation about its axis;
• e. means provided between said latch body and said shaft for transmitting motion from said handle to said shaft;
• f. means provided between said latch body and said shaft for limiting both relative rotation and relative axial translation of said shaft with respect to said latch body and for preventing axial translation during rotation and preventing rotation during axial translation, the position of said shaft with respect to said latch body at one of the limits of rotation corresponding with the position of said shaft with respect to said latch body at one of the limits of axial translation, thereby to constitute a transitional position in the motion of said shaft with respect to said base;
• and
• g. means provided between said shaft and said handle for causing, in response to relative rotation of said handle with respect to said latch body, either rotation of said shaft with respect to said latch body or axial translation of said shaft with respect to said latch body, the motions being sequential as determined by the aforesaid limits of motion of said shaft with respect to said latch body.

In a pull-up latch mechanism in which a latch pawl is to be moved both rotationally and axially on its mounting shaft:

• a. a fixed latch body having a generally cylindrical bore;
• b. a shaft supported in said bore and projecting axially in both directions therefrom and having a latch pawl mounted on a shaft projection;
• c. spring means biasing said shaft in one direction;
• d. an annular cam mounted coaxially relative to said shaft;
• e. a cam-follower cross pin secured to said shaft and maintained against said cam by said biasing means;
• f. means for applying a torque force to said cam for moving said cam rotationally;
• and
• g. means responsive to rotational movement of said cam for sequentially transmitting rotational and then axial motions to said shaft, in said order or in the reverse order, and for translating from the initial to the subsequent form of motion, all in response to rotational movement of said cam in one direction.

In a pull-up latch mechanism in which a latch pawl is to be moved both rotationally and axially on its mounting shaft:

• a. a latch body having an annular sleeve and a cylindrical bore;
• b. a shaft supported in said sleeve and projecting in at least one direction therefrom and having a latch pawl mounted on said shaft projection for axial and rotational movement with said shaft;
• c. a pair of diametrically opposed axially extending slots in said sleeve;
• d. a pair of diametrically opposed laterally extending slots in said sleeve;
• e. each of said axial slots intersecting with one of said lateral slots at a motion translation position;
• f. a rotatable annular cam positioned coaxially relative to said shaft;
• g. a cross pin secured to said shaft, opposite ends of said cross pin being maintained in engagement with said cam;
• and
• h. means connected to said cam and responsive to torque force applied thereto for moving said cam rotationally, thereby, in response to said cam being moved rotationally in the same one direction, to transmit rotational and axial motions sequentially to said shaft, in that order or in reverse order depending upon the direction of rotation of said cam.