Movable beam type hold-down clamp for machine work tables

A hold-down clamp for use on a machine table having slot and hole means to aid fastening of the clamp thereto, comprising in combination:

• a body having a base defining at least one hole to receive a fastener to fasten the base to an underlying machine table, said base supporting an upstanding holding arm housing having two similar spaced sides interconnected by a top to define a medial channel to movably receive a holding arm, said housing sides each defining a plurality of similar vertically spaced holes arrayed in paired cooperative relationship adjacent each reward side edge to receive therebetween a support pin extending through said channel and said top defining a vertical hole threaded carrying a fastening screw depending downwardly into the medial channel defined in the holding arm housing spacedly distant from the support pin;
• and
• an elongate rigid holding arm carried in the medial channel defined in the holding arm housing and extending spacedly forwardly therefrom and rearwardly beyond the holding arm housing, with the rearward end portion of the holding arm supported by the support pin and having means to prevent the passage of that reward end portion through the medial channel defined in the body, and the forward end portion of the holding arm pivotally carrying a depending workpiece holder arm with a releasably interconnected workpiece contacting shoe to contact a workpiece therebeneath and hold that workpiece against a supporting machine table when the holding arm is forced downwardly by motion of the fastening screw.