Gm Global Technolgoy Operations, Inc.

Michael H Lovell

Sanjay Mahasukhlal Shah

Kevin R Marks

Terry Andrew Kent

Paul Edward Krajewski

William R Rodgers

John Robert Bradley

Howard W Cox

Bruce Steven Shimanovski

George Thomas Winterhalter

David R Friddell

Douglas T Wohlenhaus

Darrell W Rebman

Tiffanie E Coe

Mark A Cline

Donald W Cotton

William Parker

Thomas James Malone

Arturo M Martinez

John Collins

A method and system for forming a part from a workpiece including a hollow portion, using a mandrel and a conventional press such as a stamping press includes filling the hollow portion of the workpiece with a mandrel material and transforming the mandrel material to form a mandrel. The mandrel material is removable from the formed part and may be recycled to form a mandrel for another workpiece.

Internal mandrel and method

Articles are often formed from a tubular workpiece in a process which does not usefully shape the ends of the tube. In an embodiment of the invention, tube ends may be mechanically reduced in cross section and then expanded against a secondary forming surface(s) using an electromagnetic force to obtain desired shapes for the tube ends and minimize scrapping of workpiece material.

Electromagnetic shape calibration of tubes

A tube bending assembly adapted for use with a rotary draw bender, and preferably including a bend die mounting unit for securing a plurality of stacked bend dies drivenly coupled to the bender, a bend die tower unit for structurally supporting the bend die mounting unit, a wiper die mounting unit for securing a wiper die adjacent a selected bend die, a clamp die mounting unit for positioning and securing a clamp die, a pressure die mounting unit for securing a pressure die adjacent the clamp die, a mandrel saddle unit for positioning and enabling the utilization of a mandrel assembly, a collet saddle unit for positioning and enabling the utilization of a collet, and a bolster unit that interconnects the units, so as to present an integrated assembly capable of concurrent disconnection from and connection to the bender, and thereby reducing the tool set change-over period.

Quick change bend tooling bolster

A method and apparatus for piercing a pair of aligned holes through both sides of a tube combined with the process of hydroforming the tube to final shape. After the tube is expanded and internally pressurized between upper and lower dies, a punch is driven forcefully through a cross passage in the die and through both walls of the tube, one after the other. The end of the punch is bored out sufficiently to leave a sharp edge that cuts a first slug, and the first slug is wedged into the end of the punch. The opposed wall of the tube is backed by a female die button with a cylindrical cutting edge concentric to, and equal in diameter to, the end of the punch. The end of the punch enters the die button to cleanly shear out a second hole, pushing a stack of two slugs into the die button. A pressure feed orifice properly located enters the still pressurized tube at this point, feeding positive pressure to the punch bore to blow the slugs off and out of the die button.

Method for piercing two aligned holes in a hydroformed tube

A method of forming an elongated box shape tubular frame member from a round tube includes the steps of: providing a lower die member having a cavity submerged substantially below the top surface of the lower die and having a cavity width equal to the width of the desired box shape frame member and less than the diameter of the tube. The lower die has an entry opening which opens to the top surface of the die and is defined by angularly disposed funnel walls which converge to intersect with the cavity. The round tubular blank is placed onto the lower die so that the blank rests on the angularly disposed funnel walls above the cavity. The upper die is lowered onto the lower die and has a lid wall which forces the tubular blank downwardly into the cavity while the angularly disposed funnel walls guide the blank to collapse in a manner preventing pinching of the blank between the upper and lower dies. The application of internal hydraulic pressure then expands the collapsed tube outwardly to the shape defined by the cavity of the lower die and the lid wall of the upper die.

Method for pinch free tube forming

A seal device for a hydroforming press includes a housing having a bore and a seal carrier slidable within the housing bore. The seal carrier has a bore which fits closely outside of the end of tube to be hydroformed. A V-shaped locator rigidly mounted relative to the housing aligns the end of the tube placed thereon with the carrier bore. A carrier actuator is operable to move the seal carrier between a retracted position away from the end of the tube to an extended position over the end of the tube. A resilient elastomeric annular seal carried by the seal carrier encircles the outer surface of the tube. A seal actuator carried on the seal carrier compresses the seal upon relative movement between the seal actuator and the seal carrier. A stop is engaged by the seal actuator as the seal carrier approaches the extended position so that subsequent further movement of the seal carrier compresses the seal against the tube. The locator and a tube backup fixed to an upper bed of the press encircle the tube when the press is closed, reacting against the tube when it is pressurized. A travel limit block provides a reaction member against which the locator reacts to prevent relative movement between the seal device and the press during forming.

External seal device for tube hydroforming

Growing community of inventors

Leonard, MI, United States of America

Michael H Lovell