Method and apparatus for securely clamping a drill motor to a drill plate

Abstract

A device utilizing positive and negative fluid pressure and the plurality of tandem operating components for securely clamping a drill motor to a drill plate in order to drill precisely positioned holes in a workpiece includes an annular mandrel and annular collet concentrically disposed about the cutting tool. A first end of the collet includes a plurality of longitudinally extending fingers while the mandrel has a tapered end portion having a larger external diameter than the center cylindrical portion of the mandrel. A plurality of pistons are also coaxially disposed about the cutting tool and within piston subchambers defined within the piston housing of the clamping device to extend and retract the mandrel and the collet. Once extended, the longitudinally extending fingers of the collet overlie the center cylindrical portion of the mandrel. Thus, the clamping device may be inserted through an aperture defined in a drill plate. Following its retraction, the longitudinally extending fingers of the collet overlie the tapered end of the mandrel and are correspondingly expanded. The expanded fingers engage the aperture defined by the drill plate to securely clamp the drill motor to the drill plate. The device also includes lubricant-coolant delivery and vacuum collection of chip swarf and self-cleaning features.