Abstract: An improved clamping mechanism for clamping a workpiece as it is moved through an automatic drilling machine. A workpiece, such as a wide flange beam, is supported and conveyed on a plurality of lower rollers, and a group of upper rollers are moved into clamping engagement with the upper surface of the beam. The ends of each upper roller are journalled within slides which are mounted for vertical movement on the frame of the machine, and a hydraulic cylinder unit is connected to each slide so that operation of the cylinder unit will move the upper roller in a direction toward and away from the beam supported on the lower rollers. A shaft extends parallel to the upper roller and innerconnects the slides and gears are mounted on opposite ends of the shaft and are engaged with racks mounted on the frame.

Abstract: A mechanism for individually positioning a drilling head in a multiple head drilling assembly. The assembly includes a plurality of spindle blocks arranged in side-by-side relation, and a spindle that is adapted to carry a drill head is mounted for rotation and axial movement in each block. Each spindle block is mounted for individual lateral movement in a direction normal to the axis of the spindle on guide rods, and is driven laterally by a rotatable lead screw that extends parallel to the guide rods. A recirculating ball nut is associated with each spindle block and is engaged with the lead screw. A clamping mechanism acts to selectively clamp each nut to the respective spindle block and by clamping the nut to the block, the spindle block will be moved along the guide rods on rotation of the lead screw, and by disengaging the nut from the respective spindle block, rotation of the lead screw will cause free rotation of the nut without movement of the block.

Abstract: An apparatus for sensing the location of a structural member on which a working operation is to be performed. The apparatus includes a probe that is connected to a rack and is mounted for movement between an inoperative position and an operative position, where the probe will be in engagement with the structural member. The rack is carried by a piston which is slideable within a cylinder and by introducing fluid pressure into one end of the cylinder, the rack will be extended to thereby move the probe from the inoperative to the operative position. Engaged with the rack is a pinion and linear movement of the rack will rotate the pinion and rotation of the pinion acts through a resolver to generate a signal indicating the precise position of the structural member.