Abstract: A peck feed drill incorporates a motor gear quill and a feed control assembly together on a moving race track shaped piston. External construction of the housing permits mounting of an indexing adaptor plug for attachment of drill bushings. Internal construction of the housing provides for passage of air to the various components to which control tool operation. Valves within the air logic circuitry are multi-functional to minimize the number of parts.

Abstract: An airfeed peck drill includes a substantially cylindrical drill quill contained within a cylinder in a housing. On the rear end of the drill quill is located an offset piston, the offset piston provides force for the entry and exit of the drill quill into or from a workpiece. On the front end of the drill quill is a reaction bracket which is attached to a motion transfer arm. On the rear end of the motion transfer arm is an engagement arm which is constructed and arranged to engage a piston rod which extends from a damping cylinder.

Abstract: An airfeed peck drill includes a substantially cylindrical drill quill contained within a cylinder in a housing. On the rear end of the drill quill is located an offset piston, the offset piston provides force for the entry and exit of the drill quill into or from a workpiece. On the front end of the drill quill is a reaction bracket which is attached to a motion transfer arm. On the rear end of the motion transfer arm is an engagement am which is constructed and arranged to engage a piston rod which extends from a damping cylinder.

Abstract: An airfeed peck drill includes a substantially cylindrical drill quill contained within a cylinder in a housing. On the rear end of the drill quill is located an offset piston, the offset piston provides force for the entry and exit of the drill quill into or from a workpiece. On the front end of the drill quill is a reaction bracket which is attached to a motion transfer arm. On the rear end of the motion transfer arm is an engagement arm which is constructed and arranged to engage a piston rod which extends from a damping cylinder.

Abstract: An attachment for clamping a portable drill to a work piece includes a foot member which positions a portable drill with respect to a work piece. A contact pad applies pressure to the surface of the work piece. Located between the contact pad and the means for engagement of the portable drill is a guide path in which a housing is slidably mounted. Affixed to the housing is a means for applying a vertical force and a collet member. Said means being anti-back drivable. The vertical force is applied to a mandrel so that the mandrel expands the collet. Once the collet has been expanded, a force is placed on the contact pad and on the means for engaging the portable drill. Consequently, the portable drill is held in place at the desired location for drilling a finish hole using minimal force.

Abstract: A test fixture for comparing the performance characteristics of air feed drills includes a frame and a simulated linear thrust load. Included also is a peck counter, a linear transducer for measuring stroke length, and an rpm counter. These measurements are visually displayed and may be optionally used as inputs for the calculation of various operational ratios which may also be displayed.

Abstract: An automated and adjustable control system for conducting peck drilling operations wherein a drill bit is advanced stepwise in successively increasing penetrations, rapidly retracted after each penetration to remove cuttings, thereafter rapidly advanced toward a work face and then slowed to a drilling advanced rate beginning with the bit a predetermined distance from the work face. Preferably, a pneumatic means rapidly retracts the drill upon completion of each penetration step. A feed rate control unit is partially retracted but limited to a distance less than retraction of the drill. When the drill is rapidly advanced by pneumatic means during each penetration step, the feed rate is decreased by the feed rate control unit to a uniform drilling rate prior to engaging the work face in the work piece.