Punch press workholder

Claim 2

A workholder for a machine tool having a cross slide for positioning a workpiece, comprising in combination: first and second arm members pivotally joined intermediate their ends, with one end of one of said members being affixed to said cross slide; work engaging jaws affixed to the other ends of said first and second arm members in opposing relationship to each other; actuator means coacting with the first ends of said first and second arm members to pivotally open and close said jaws; and flexure means intermediate the pivot point and the first end of one of said arm members to permit movement of said arm members in the same plane as the pivoting movement.

Claim 3

Apparatus according to claim 1 wherein said flexure means is an integral part of said one arm member.

Claim 4

Apparatus according to claim 2 wherein said flexure means is an area of reduced cross-section.

Claim 5

A punch press for working on sheets of material, said punch press including table means for supporting a sheet of material, said table means including support surface means for supportingly engaging a major side surface of the sheet of material, punch means for forming openings in the sheet of material while it is disposed on said table means, die means for cooperating with said punch means, means for effecting movement of said punch means through a work stroke in a first direction transverse to said support surface means and for effecting movement of said punch means through a return stroke in a second direction opposite to said first direction, said punch means being effective to move at least a portion of the sheet of material in one of said directions during at least a portion of one of said strokes, stripper means for effecting disengagement of the sheet of material from said punch means during a return stroke by limiting movement of the sheet of material in the second direction, and gripper means for holding the sheet of material against movement in a direction extending generally parallel to said support surface means during work and return strokes of said punch means and for enabling at least a portion of the sheet of material to move in said one direction during at least one of said strokes of said punch means, said gripper means including clamp surface means for clampingly engaging the sheet of material during work and return strokes of said punch means, a base portion, resiliently yieldable connection means for interconnecting said clamp surface means and said base portion and for enabling said clamp surface means to move relative to said support surface means through a substantial distance in at least said one of said directions under the influence of forces applied to the sheet of material by said punch means.

Claim 6

A punch press for working on sheets of material, said punch press including table means for supporting a sheet of material, said table means including support surface means for supportingly engaging a major side surface of the sheet of material, punch means for forming openings in the sheet of material while it is disposed on said table means, die means for cooperating with said punch means, means for effecting movement of said punch means through a work stroke in a first direction transverse to said support surface means and for effecting movement of said punch means through a return stroke in a second direction opposite to said first direction, said punch means being effective to move at least a portion of the sheet of material in one of said directions during at least a portion of one of said strokes, stripper means for effecting disengagement of the sheet of material from said punch means during a return stroke by limiting movement of the sheet of material in the second direction, and gripper means for holding the sheet of material against movement in a direction extending generally parallel to said support surface means during work and return strokes of said punch means and for enabling at least a portion of the sheet of material to move in said one direction during at least one of said strokes of said punch means, said gripper means including clamp surface means for clampingly engaging the sheet of material during work and return strokes of said punch means, a base portion, resiliently yieldable connection means for interconnecting said clamp surface means and said base portion and for enabling said clamp surface means to move relative to said support surface means through a substantial distance in at least said one of said directions under the influence of forces applied to the sheet of material by said punch means.

Claim 7

A punch press as set forth in claim 4 wherein said clamp surface means includes first surface means for engaging one side of a sheet of material and second surface means for engaging another side of a sheet of material, said gripper means further including a first elongated support portion connected with said first surface means and a second elongated support portion connected with said second surface means, said first and second elongated support portions having a substantially greater resistance to deflection in said one of said directions than said resiliently yieldable connection means.

Claim 8

A punch press as set forth in claim 5 wherein said resiliently yieldable connection means is integrally formed with said first elongated member.

Claim 9

A punch press as set forth in claim 4 wherein said gripper means includes an elongated arm extending between said resiliently yieldable connection means and said clamp surface means, said arm having a first cross sectional area in a plane extending perpendicular to the longitudinal axis of said arm, said resiliently yieldable connection means having a second cross sectional area which is substantially smaller than said first cross sectional area.

Claim 10

A punch press as set forth in claim 4 wherein said clamp surface means includes a first surface means for engaging one side of the sheet of material and a second surface means for engaging an opposite side of the sheet of material, said gripper means further including a first elongated arm having an inner end portion connected with said resiliently yieldable connection means and an outer end portion connected with said first surface means, a second elongated arm connected at an outer end portion with said second surface means, and connection means for pivotally connecting said second arm with said first arm at a location intermediate said inner and outer end portions of said first arm.

Claim 11

A punch press as set forth in claim 8 wherein said inner end portion of said first arm is integrally formed with said resiliently yieldable connection means and has a cross sectional area which is substantially greater than the cross sectional area of said yieldable connection means.

Claim 12

A punch press as set forth in claim 4 further including stop means for limiting movement of said clamp surface means in the second direction under the influence of forces applied to the sheet of material by said punch means as said puNch means is moved through a return stroke.

Claim 13

A punch press for working on sheets of material, said punch press including table means for supporting a sheet of material, punch means for forming openings in the sheet of material while it is disposed on said table means, means for effecting movement of said punch means through working and return strokes, and gripper means for holding the sheet of material during working and return strokes of said punch means, said gripper means including first and second arm members pivotally joined intermediate their ends, one end of one of said members being connected with said table, work engaging jaws affixed to the other ends of said first and second arm members in opposing relationship to each other, actuator means coacting with the first ends of said first and second arm members to pivotally open and close said jaws, and flexure means intermediate the pivot point and the first end of one of said arm members to permit movement of said arm members in the same plane as the pivoting movement.

Claim 14

A punch press for working on sheets of material, said punch press including table means for supporting a sheet of material, punch means for forming openings in the sheet of material while it is disposed on said table means, means for effecting movement of said punch means through working and return strokes, and gripper means for holding the sheet of material during working and return strokes of said punch means, said gripper means including first and second arm members pivotally joined intermediate their ends, one end of one of said members being connected with said table, work engaging jaws affixed to the other ends of said first and second arm members in opposing relationship to each other, actuator means coacting with the first ends of said first and second arm members to pivotally open and close said jaws, and flexure means intermediate the pivot point and the first end of one of said arm members to permit movement of said arm members in the same plane as the pivoting movement.

Claim 15

Apparatus according to claim 11 wherein said flexure means is an integral part of said one arm member.

Claim 16

Apparatus according to claim 12 wherein said flexure means is an area of reduced cross-section.