Apparatus for actuating a work gripping device

Claim 1

A device for actuating a work gripping collet comprising: a. a cylinder adapted to be mounted to a machine tool spindle, b. a tubular through hole collet drawing member being mounted within said cylinder for axial movement relative thereto, c. annular piston means slideably received in said cylinder and including means for axially moving said member relative to said cylinder, d. said drawing member passing through said piston means, e. said piston means having a first pressure face cooperating with one end of said cylinder to form a first expansible chamber and having a second pressure face cooperating with the other end of said cylinder to form a second expansible chamber, f. said piston means including first valve means for admitting fluid under pressure to said first chamber, said first valve means being entirely supported by said piston means and movable therewith, g. said first valve means extending through said piston and forming a portion of said first and second pressure faces, h. said piston means including second valve means for admitting fluid under pressure to said secoNd chamber, said second valve means being entirely supported by said piston means and movable therewith, i. said second valve means extending through said piston and forming a portion of said first and second pressure faces, j. said first valve means including means for venting said first chamber when fluid under pressure is admitted to said second chamber and said second valve means including means for venting said second chamber when fluid under pressure is admitted to said first chamber, k. means for alternatively connecting a source of fluid under pressure to said first and second chambers through said first and second valve means, respectively, l. said first valve means including means for trapping fluid in said first chamber when the pressure of the source of fluid under pressure is reduced while said first chamber is connected to the source of fluid under pressure, m. said piston means, cylinder and drawing member being mounted for unitary rotation, n. said first and second valve means being mounted in said piston means radially outward of the axis of rotation of said piston means, cylinder and drawing member for movement relative thereto in a direction parallel to said axis of rotation, and o. each of said first and second valve means including a pressure responsive valve piston having a face thereof forming said pressure face portion.

Claim 2

A device for actuating a work gripping collet comprising: a. a cylinder adapted to be mounted to a machine tool spindle, b. a tubular through hole collet drawing member being mounted within said cylinder for axial movement relative thereto, c. annular piston means slideably received in said cylinder and including means for axially moving said member relative to said cylinder, d. said drawing member passing through said piston means, e. said piston means having a first pressure face cooperating with one end of said cylinder to form a first expansible chamber and having a second pressure face cooperating with the other end of said cylinder to form a second expansible chamber, f. said piston means including first valve means for admitting fluid under pressure to said first chamber, said first valve means being entirely supported by said piston means and movable therewith, g. said first valve means extending through said piston and forming a portion of said first and second pressure faces, h. said piston means including second valve means for admitting fluid under pressure to said secoNd chamber, said second valve means being entirely supported by said piston means and movable therewith, i. said second valve means extending through said piston and forming a portion of said first and second pressure faces, j. said first valve means including means for venting said first chamber when fluid under pressure is admitted to said second chamber and said second valve means including means for venting said second chamber when fluid under pressure is admitted to said first chamber, k. means for alternatively connecting a source of fluid under pressure to said first and second chambers through said first and second valve means, respectively, l. said first valve means including means for trapping fluid in said first chamber when the pressure of the source of fluid under pressure is reduced while said first chamber is connected to the source of fluid under pressure, m. said piston means, cylinder and drawing member being mounted for unitary rotation, n. said first and second valve means being mounted in said piston means radially outward of the axis of rotation of said piston means, cylinder and drawing member for movement relative thereto in a direction parallel to said axis of rotation, and o. each of said first and second valve means including a pressure responsive valve piston having a face thereof forming said pressure face portion.

Claim 6

A device for actuating a work gripping collet comprising: a. a cylinder adapted to be mounted to a machine tool spindle, b. a tubular through hole collet drawing member being mounted within said cylinder for axial movement relative thereto, c. said drawing member comprising: a first tubular member having an external surface and including means at one end for securing a work gripping collet thereto, first and second slots in the external surface of said first tubular member, a second tubular member having internal and external surfaces and being concentrically positioned around and rigidly secured to said first member, the internal surface of said second member being flush with the external surface of said first member thereby forming a pair of fluid-tight passageways, first and second longitudinally displaced apertures in said second member positioned above one of said slots, third and fourth longitudinally displaced apertures in said second member positioned above the other said slots, d. annular piston means slideably received in said cylinder and including means for axially moving said member relative to said cylinder. e. said drawing member passing through said piston means, f. said piston means having a first pressure face cooperating with one end of said cylinder to form a first expansible chamber and having a second pressure face cooperating with the other end of said cylinder to form a second expansible chamber, g. said piston means including first valve means for admitting fluid under pressure to said first chamber and second valve means for admitting fluid under pressure to said second chamber, h. said first and second valve means being entirely supported by said piston means and movable therewith to form a portion of said first and second pressure faces, i. said first valve means including means for venting said first chamber when fluid under pressure is admitted to said second chamber and said second valve means including means for venting said second chamBer when fluid under pressure is admitted to said first chamber, and j. means for alternatively connecting a source of fluid under pressure to said first and second chambers through said first and second valve means, respectively, k. said first valve means including means for trapping fluid in said first chamber when the pressure of the source of fluid under pressure is reduced while said first chamber is connected to the source of fluid under pressure, l. said piston means, cylinder and drawing member being mounted for unitary rotation, m. said first and second valve means being mounted in said piston means radially outward of the axis of rotation of said piston means, cylinder and drawing member for movement relative thereto in a direction parallel to said axis of rotation.

Claim 7

A device for actuating a work gripping collet comprising: a. a cylinder adapted to be mounted to a machine tool spindle, b. a tubular through hole collet drawing member being mounted within said cylinder for axial movement relative thereto, c. said drawing member comprising: a first tubular member having an external surface and including means at one end for securing a work gripping collet thereto, first and second slots in the external surface of said first tubular member, a second tubular member having internal and external surfaces and being concentrically positioned around and rigidly secured to said first member, the internal surface of said second member being flush with the external surface of said first member thereby forming a pair of fluid-tight passageways, first and second longitudinally displaced apertures in said second member positioned above one of said slots, third and fourth longitudinally displaced apertures in said second member positioned above the other said slots, d. annular piston means slideably received in said cylinder and including means for axially moving said member relative to said cylinder. e. said drawing member passing through said piston means, f. said piston means having a first pressure face cooperating with one end of said cylinder to form a first expansible chamber and having a second pressure face cooperating with the other end of said cylinder to form a second expansible chamber, g. said piston means including first valve means for admitting fluid under pressure to said first chamber and second valve means for admitting fluid under pressure to said second chamber, h. said first and second valve means being entirely supported by said piston means and movable therewith to form a portion of said first and second pressure faces, i. said first valve means including means for venting said first chamber when fluid under pressure is admitted to said second chamber and said second valve means including means for venting said second chamBer when fluid under pressure is admitted to said first chamber, and j. means for alternatively connecting a source of fluid under pressure to said first and second chambers through said first and second valve means, respectively, k. said first valve means including means for trapping fluid in said first chamber when the pressure of the source of fluid under pressure is reduced while said first chamber is connected to the source of fluid under pressure, l. said piston means, cylinder and drawing member being mounted for unitary rotation, m. said first and second valve means being mounted in said piston means radially outward of the axis of rotation of said piston means, cylinder and drawing member for movement relative thereto in a direction parallel to said axis of rotation.