David Martin Jensen

US Patent:

6915672, Jul 12, 2005

Filed:

Mar 12, 2004

Appl. No.:

10/799979

Inventors:

Mircea M. Ghiran - Lake Orion MI, US
Spyros P. Mellas - Waterford MI, US
David R. Jensen - Swartz Creek MI, US

Assignee:

General Motors Corporation - Detroit MI

International Classification:

B21D028/28
B21D039/20

US Classification:

72 55, 72 56, 83 53, 83 54, 294211

Abstract:

A hydrotapping power unit is disclosed that is operable to position and hold a hydrotapping tool in a home position adjacent a part while the part is being hydroformed in a die cavity, to then advance the tool to pierce a hole in the hydroformed part while the part remains in the die cavity and under pressure and then continue to advance the tool to inwardly extrude the part about the hole, to then further advance while also rotating the tool so that the tool is fed at a feed rate equal to the thread pitch of the tool to thereby form a thread in the pierced hole, and finally to retract while also rotating the tool but in the reverse direction and at the same feed rate to release the tool from the threaded hole. The power unit performing these operations includes a linearly moveable shaft for holding the tool, a powered device for rotating the shaft, a powered device for linearly moving the shaft, and a lead screw connection between the latter powered device and the shaft having a thread pitch equal to that of the tool.

US Patent:

7003995, Feb 28, 2006

Filed:

Mar 12, 2004

Appl. No.:

10/799068

Inventors:

Mircea M. Ghiran - Lake Orion MI, US
Spyros P. Mellas - Waterford MI, US
David R. Jensen - Swartz Creek MI, US
Paul D. Larsen - Fenton MI, US

Assignee:

General Motors Corporation - Detroit MI

International Classification:

B21D 22/00

US Classification:

72 55, 72 71, 72325, 7245301, 72432

Abstract:

A hydrotapping power unit is disclosed that is operable to hold a hydrotapping tool in a home position adjacent a part while the latter is being hydroformed in a die cavity, to then advance the tool to pierce a hole in the hydroformed part while the part remains in the die cavity and under pressure and then continue to advance the tool to inwardly extrude the part about the hole, to then further advance while also rotating the tool at a feed rate equal to the thread pitch of the tool to thereby form a thread in the pierced hole, and finally retract while also rotating the tool but in the reverse direction and at the same feed rate to release the tool from the threaded hole. The power unit for performing these operations includes a linearly moveable shaft for holding the tool, a powered device for rotating the shaft, another powered device connected to the shaft by a lead screw connection having a thread pitch equal to that of the tool, and a third powered device that is adapted to intercept and prevent shock loading on the tool from the piercing operation and thereby on the shaft from reaching the lead screw connection.

US Patent:

7124618, Oct 24, 2006

Filed:

Mar 7, 2006

Appl. No.:

11/369248

Inventors:

Mike M. Ghiran - Lake Orion MI, US
Sanjay M. Shah - Troy MI, US
David R. Jensen - Swartz Creek MI, US
Terry A. Kent - East China MI, US
Paul D. Larsen - Fenton MI, US

Assignee:

GM Global Technology Operations, Inc. - Detroit MI

International Classification:

B21D 26/02
B21D 9/15

US Classification:

72451, 72 57, 72 60, 72 63, 294211, 100272

Abstract:

A clamp assembly for a hydroforming die includes a stationary lower bed to support a lower die half of the hydroforming die, a stationary upper bed spaced above the lower bed, at least one guide post extending between the lower bed and the upper bed, a movable slide disposed between the upper bed and the lower bed and movable along the at least one guide post to support an upper die half of the hydroforming die, a lifting cylinder operatively connected to the movable slide to move the movable slide and upper die half toward and away relative to the lower die half, at least one link mechanism connected to the upper bed and the movable slide to equalize a force on the hydroforming die, and at least one linkage cylinder operatively connected to the at least one link mechanism to activate the at least one link mechanism to prevent the movable slide and upper die half from moving away from the lower die half to keep the hydroforming die closed during a hydroforming process.

US Patent:

7404310, Jul 29, 2008

Filed:

Jan 10, 2007

Appl. No.:

11/621593

Inventors:

Mike M. Ghiran - Lake Orion MI, US
Wei Ji - Troy MI, US
Paul D. Larsen - Fenton MI, US
David R. Jensen - Swartz Creek MI, US

Assignee:

GM Global Technology Operations, Inc. - Detroit MI

International Classification:

B21D 9/01
B23Q 3/14

US Classification:

724662, 72208, 72149, 72217, 269 481

Abstract:

A mandrel assembly is provided for insertion into a hollow tube to support the interior walls of the tube during bending of the tube in a tube bending apparatus. The mandrel assembly includes at least one mandrel segment that is adapted for positioning within the tube and has an exterior support surface for supporting the interior walls of the tube during bending. The mandrel segment is anchored at a fixed axial location within the tube by an anchoring device that is radially expandable and retractable between an expanded condition in which an anchor shoe is engaged with the interior wall of the tube and a retracted condition in which the anchor shoe is loose within the tube. A mandrel support rod is attached to the anchoring device for inserting and withdrawing the anchoring device into the tube when the anchor shoe is retracted.

US Patent:

7937979, May 10, 2011

Filed:

Aug 12, 2008

Appl. No.:

12/189877

Inventors:

Mike M. Ghiran - Lake Orion MI, US
Ranny Joe Nunley - Metamora MI, US
David R. Friddell - Grand Blanc MI, US
William M. Crantas - Highland MI, US
Kevin R. Marks - Durand MI, US
David R. Jensen - Swartz Creek MI, US
Paul D. Larsen - Fenton MI, US

Assignee:

GM Global Technology Operations LLC - Detroit MI

International Classification:

B21D 39/08
B23P 17/02

US Classification:

72 58, 72 61, 72 62, 294211

Abstract:

A hydroform die includes a plurality of seal units to provide fluid to die cavities. The plurality of seal units each define a piston cylinder. A piston is located within the cylinder and is selectively moveable between an open and a closed position. Additionally, the piston at least partially defines a valve chamber located on a first side of the piston and a piston chamber located on a second side of the piston. A piston fluid passage is defined by the piston to fluidly connect the valve chamber and the piston chamber.

US Patent:

8020272, Sep 20, 2011

Filed:

Apr 20, 2007

Appl. No.:

11/737790

Inventors:

Mike M. Ghiran - Lake Orion MI, US
Spyros P. Mellas - Waterford MI, US
David R. Jensen - Swartz Creek MI, US
Paul D. Larsen - Fenton MI, US

Assignee:

GM Global Technology Operations LLC - Detroit MI

International Classification:

B23P 17/00

US Classification:

294211, 29505, 29507, 29516, 298972, 29447

Abstract:

A method is provided for joining tubes. An outer tube and an inner tube are provided. An end of the inner tube is inserted into an end of the outer tube to form an overlapped region of tube wall and form a pressure tight joint between the tubes. The overlapped region of the tubes is heated. The tubes are placed in pair of dies having a die cavity adjacent to the outer tube. Pressure is introduced into the tubes to expand the overlapped region of the tubes outwardly into the die cavity and thereby form an interlocking joint between the overlapped region of the outer tube and the inner tube.

US Patent:

7360384, Apr 22, 2008

Filed:

Mar 23, 2007

Appl. No.:

11/690264

Inventors:

Mike M. Ghiran - Lake Orion MI, US
Paul D. Larsen - Fenton MI, US
David R. Jensen - Swartz Creek MI, US
Gerry A. Harmon - Clawson MI, US
Sanjay M. Shah - Troy MI, US
Terry A. Kent - East China MI, US

Assignee:

GM Global Technology Operations, Inc. - Detroit MI

International Classification:

B21D 26/02
B21D 28/18

US Classification:

72 55, 72 58, 72 62

Abstract:

An apparatus and method for hydroshearing and hydrotrimming for a hydroforming die includes a cutting insert fixed relative to the hydroforming die. The apparatus and method also includes a disposable insert fixed relative to the hydroforming die. The apparatus and method further includes a plunger movable relative to the hydroforming die to allow fluid within a tubular member to force a wall portion of the tubular member outward against the plunger and be sheared in the hydroforming die to trim the tubular member.

US Patent:

57826242, Jul 21, 1998

Filed:

Oct 25, 1996

Appl. No.:

8/738087

Inventors:

David L. Jensen - Rochester MI

International Classification:

F01C 308

US Classification:

418195

Abstract:

Fluid compressor or expander having a main rotor with discrete arcked-helical flutes that have ruled surface roots that match the predominantly planar tips of the teeth of the associated gate rotors and provide effective fluid sealing as the gate rotor teeth sweep through the flutes of the main rotor during compressor or expander operation. The flutes can be readily and economically made by end milling, in which a first flute is milled with a minimized number of milling passes such as a first pass to make one arcked-helical flank and a portion of the arcked-helical root of a first flute and a second pass to make the opposing arcked-helical flank and another portion of the arcked-helical root of the first flute. Additional discrete flutes are made in a similar manner until the main rotor is completed.