Self-locking and adjustable dual ratchet clamping apparatus

A single rail self-locking and adjustable clamping apparatus comprising:

• a frame having a longitudinal body comprising a rail, a first end and a second end, the frame further comprising a ratchet rack extending along a longitudinal portion of the rail;
• a fixed jaw configured to be selectively mounted at either the first end or the second end of the frame, the fixed jaw having a first gripping surface;
• a movable jaw supported by the frame and configured to be slidable along the rail toward and away from the fixed jaw, the movable jaw having a second gripping surface arranged to oppose the first gripping surface;
• a first ratchet system supported on the movable jaw and comprising:
• a user-operable lever rotatable about a first pivot axis;
• a ratchet cam coupled to the lever;
• a locking pawl biased by a first elastic member into engagement with the ratchet cam;
• wherein the first ratchet system permits rotation of the lever in a first rotational direction and resists rotation in an opposite rotational direction to provide rotational self-locking;
• a second ratchet system comprising:
• a driving pawl configured to engage the ratchet rack of the frame;
• and
• a second elastic member biasing the driving pawl into engagement with the ratchet rack;
• wherein the second ratchet system permits movement of the driving pawl along the rail in a forward direction and resists movement in an opposite direction to provide linear self-locking;
• a linkage system operatively coupling the first ratchet system to the driving pawl;
• wherein rotation of the lever is transmitted through the linkage system to drive incremental linear advancement of the driving pawl along the ratchet rack while the second ratchet system is engaged, thereby advancing the movable jaw along the rail relative to the fixed jaw;
• wherein, when the fixed jaw is mounted at the first end of the frame, incremental advancement of the movable jaw reduces a distance between the first and second gripping surfaces to apply a clamping force;
• wherein, when the fixed jaw is mounted at the second end of the frame, incremental advancement of the movable jaw increases a distance between the first and second gripping surfaces to apply a spacing force;
• and
• wherein, when user actuation of the lever is released, the first and second ratchet systems cooperate to retain the clamping force or the spacing force and prevent reverse movement of the movable jaw.

A dual rail self-locking and adjustable clamping apparatus comprising:

• a frame having a generally U shape longitudinal body comprising a first rail, a second rail spaced from and substantially parallel to the first rail, and a bridging section connecting the first and second rails at one end, the first rail comprising a ratchet rack extending along a longitudinal portion thereof;
• a fixed jaw spanning between the first and second rails and fixed relative to the frame, the fixed jaw having a first gripping surface;
• a movable jaw spanning between the first and second rails and configured to be slidable along the frame toward and away from the fixed jaw, the movable jaw having a second gripping surface arranged to oppose the first gripping surface;
• a first ratchet system supported on the movable jaw and comprising:
• a user-operable lever rotatable about a first pivot axis;
• a ratchet cam coupled to the lever;
• a locking pawl biased by a first elastic member into engagement with the ratchet cam;
• wherein the first ratchet system permits rotation of the lever in a first rotational direction and resists rotation in an opposite rotational direction to provide rotational self-locking;
• a second ratchet system comprising:
• a driving pawl configured to engage the ratchet rack on the first rail;
• and
• a second elastic member biasing the driving pawl into engagement with the ratchet rack;
• wherein the second ratchet system permits movement of the driving pawl along the first rail in a forward direction toward the fixed jaw and resists movement in an opposite direction to provide linear self-locking;
• a linkage system operatively coupling the first ratchet system to the driving pawl;
• wherein rotation of the lever is transmitted through the linkage system to drive incremental linear advancement of the driving pawl along the ratchet rack while the second ratchet system is engaged, thereby advancing the movable jaw toward the fixed jaw along the dual-rail frame;
• wherein incremental advancement of the movable jaw reduces a distance between the first and second gripping surfaces to apply a clamping force to a workpiece;
• and
• wherein, when user actuation of the lever is released, the first and second ratchet systems cooperate to retain the clamping force and prevent reverse movement of the movable jaw along the frame.