US 5,395,187 A · Method and apparatus for attaching a drill motor to a drill plate with a clamping device having an expandable collet

Abstract

A device 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 element. 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 pneumatically-actuated piston is also coaxially disposed about the cutting element 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 hook behind the periphery of the aperture defined in the drill plate and securely clamps the drill motor to the drill plate.

Claims26

Dependent claims

A device for clamping a drill motor to a drill plate and for receiving a cutting element, said clamping device comprising:

an annular mandrel defining a cylindrical internal bore through which the cutting element may extend, said mandrel having a center cylindrical portion having a first external diameter and a tapered end portion having a second external diameter greater than the first external diameter;
an annular collet concentrically disposed about said mandrel and having a first end including a plurality of longitudinally extending fingers;
means, including an annular piston, for longitudinally extending said mandrel and collet from a retracted position to an extended position such that said mandrel extends beyond said collet and the plurality of longitudinally extending fingers of said collet overlie the central cylindrical portion of said mandrel, and wherein said annular piston defines a bore having a longitudinal axis extending coaxial with the longitudinal axes of said mandrel and said collet;
and
means for longitudinally retracting said mandrel within said collet from the extended position to the retracted position such that the longitudinally extending fingers of said collet overlie the tapered end portion of said mandrel and correspondingly expand radially,
whereby the plurality of longitudinally extending fingers hook behind the drill plate through which said mandrel and collet extend.

3 more elements

A method for clamping a drill motor to a drill plate with a clamping device having a mandrel and a collet, concentrically disposed about the mandrel and having a plurality of longitudinally extending fingers, adapted for longitudinal movement in response to longitudinal movement of an annular piston, wherein the annular piston, mandrel and collet are disposed coaxially and define a substantially cylindrical longitudinal bore for receiving a cutting element, the method comprising the steps of:

urging the annular piston of the clamping device forward such that the piston forces the mandrel and collet longitudinally forward such that the mandrel and collet may be extended through an aperture in the drill plate;
and
hooking the plurality of extended, longitudinally extending fingers onto a rear face of the drill plate.

Dependencies are inferred from the claim text.

Method and apparatus for attaching a drill motor to a drill plate with a clamping device having an expandable collet

Life of this patent

Method and apparatus for attaching a drill motor to a drill plate with a clamping device having an expandable collet

Life of this patent

Abstract

Claims26