Abstract: An electrode assembly for electro-hydraulic forming tool in which the insulation sleeve is assembled over an electrode rod. The insulation sleeve has a deflection surface that is beveled or oriented at an angle relative to the axis of the electrode rod. The electrode assembly may include a replaceable conical receptacle that facilitates placement of an electrode tip an insulation sleeve tip. An electrode tip profile that is shaped to minimize erosion caused by discharge of the electro-hydraulic forming machine.

Abstract: A method of manufacturing a drawn panel and a die set. The method includes clamping a blank between a binder and a die that defines a cavity. A first draw punch contacts the blank in advance of a second punch that subsequently engages the blank. A central area of the blank is drawn by the first draw punch that clamps a central area of the blank against a lower die. Side areas of the blank are drawn into the cavity by the side punches while the central punch clamps the blank again the lower die.

Abstract: A method of manufacturing a drawn panel and a die set. The method includes clamping a blank between a binder and a die that defines a cavity. A first draw punch contacts the blank in advance of a second punch that subsequently engages the blank. A central area of the blank is drawn by the first draw punch that clamps a central area of the blank against a lower die. Side areas of the blank are drawn into the cavity by the side punches while the central punch clamps the blank again the lower die.

Abstract: A method of reinforcing a part formed from a sheet metal panel that has a predetermined area that requires reinforcement by forming a grid pattern of V-shaped channels in the predetermined area. The grid pattern may be formed by wire electrodes in an electro-hydraulic forming tool having a one-sided die. Alternatively, the grid pattern may be formed by a plurality of electrodes that are arranged in an array that is aligned in at least two directions on the opposite side of the part from the one-sided die.

Abstract: A hemming tool for forming a hem securing an outer panel to an inner panel. The hemming tool includes a hemming die that has a first portion of a forming surface with a first coefficient of friction and a second portion that has a second coefficient of friction that is greater than the first portion. A flange on the outer panel is initially engaged by the first surface to begin forming the hem flange toward the inner panel. The flange is engaged by the second hemming surface to continue forming the flange toward the inner panel. A method of hemming a sheet metal assembly including an inner and an outer panel is also disclosed that utilizes the hemming die that has a forming surface with a second coefficient of friction that is greater than the first portion to reduce flange creep and roll-in during a hemming operation.

Abstract: A tool and method of hemming a panel wherein the tool engages a flange to apply a compressive force with a stop initially preventing a distal end of the flange from moving inwardly. The hemming tool bends the intermediate portion of the flange between the flange bend and the distal end toward the panel. The stop is withdrawn to allow the flange to be progressively formed toward the panel until the distal end is aligned with the intermediate portion.

Abstract: A method of reinforcing a part formed from a sheet metal panel that has a predetermined area that requires reinforcement by forming a grid pattern of V-shaped channels in the predetermined area. The grid pattern may be formed by wire electrodes in an electro-hydraulic forming tool having a one-sided die. Alternatively, the grid pattern may be formed by a plurality of electrodes that are arranged in an array that is aligned in at least two directions on the opposite side of the part from the one-sided die.

Abstract: A system for electro-hydraulically forming a sheet metal part in an electro-hydraulic forming (EHF) machine. The part in a first shape is placed in the EHF machine between a one-sided forming die and a chamber that is filled with a liquid. An electrode is discharged in the chamber to form the part toward the forming die. The electrode is advanced within the chamber toward the part and a subsequent discharge is provided in the chamber to form the part. A gap discharge EHF machine and a wire discharge EHF machine may be used in the system.

Abstract: A tool and method of hemming a panel wherein the tool engages a flange to apply a compressive force with a stop initially preventing a distal end of the flange from moving inwardly. The hemming tool bends the intermediate portion of the flange between the flange bend and the distal end toward the panel. The stop is withdrawn to allow the flange to be progressively formed toward the panel until the distal end is aligned with the intermediate portion.

Abstract: A system for electro-hydraulically forming a sheet metal part in an electro-hydraulic forming (EHF) machine. The part in a first shape is placed in the EHF machine between a one-sided forming die and a chamber that is filled with a liquid. An electrode is discharged in the chamber to form the part toward the forming die. The electrode is advanced within the chamber toward the part and a subsequent discharge is provided in the chamber to form the part. A gap discharge EHF machine and a wire discharge EHF machine may be used in the system.

Abstract: A method of flange trimming a sheet metal panel to form a part including flanges for subsequent hemming or weld operation is disclosed. The method utilizes an electro-hydraulic forming (EHF) tool to form a channel within which a flange is cut out in a trimming operation. A combined flange/trim die may be provided in which both a channel forming operation and a flange trimming operation may be performed. A manufacturing system for fabricating a part by forming a channel in a peripheral portion and cutting the channel area to form a flange. The method also relates to a die for an EHF tool that defines a channel-shaped recess and has a trim edge for cutting a flange into the channel.

Abstract: A method of forming a blank into a part shape is provided in which the blank is drawn into one or more channels sequentially to form at least one pocket of material that is available to be drawn into the die cavity. Each pocket is formed by applying liquid pressure or mechanical pressure to form the blank into the channels. The channels may be filled with a liquid to reduce friction. Alternatively, portions of the blank may be drawn into a channel to form a first stage preform that includes a pocket. The pocket of the first stage preform is then drawn into the die cavity in a first partial drawing stage. The steps of drawing material into the channel and then into the die cavity may be repeated one or more times until the part is fully drawn into the desired shape.

Abstract: A method of flange trimming a sheet metal panel to form a part including flanges for subsequent hemming or weld operation is disclosed. The method utilizes an electro-hydraulic forming (EHF) tool to form a channel within which a flange is cut out in a trimming operation. A combined flange/trim die may be provided in which both a channel forming operation and a flange trimming operation may be performed. A manufacturing system for fabricating a part by forming a channel in a peripheral portion and cutting the channel area to form a flange. The method also relates to a die for an EHF tool that defines a channel-shaped recess and has a trim edge for cutting a flange into the channel.

Abstract: A hydro-forming tool for use in a method of forming a blank into a liquid filled chamber. The chamber is formed by a container ring and a moveable wall that together define a variable volume chamber for containing the liquid. The wall is moveable relative to the container ring to provide a chamber in which the volume of liquid required to back up the blank is minimized. The liquid reduces friction at the chamber entry rim. Liquid may be ported through a counter punch to hydro-form the blank into the detail forming areas.

Abstract: An apparatus and method for forming a style line with a sharp radius in a metal with lower formability than that of mild steel is disclosed. The apparatus and method use a die set with a means to back a portion of the metal having the style line formed with a material that moves with the surface of the style line as it is formed. In one embodiment an elastic member backs the metal panel, and in another embodiment a fluid medium backs the metal panel where the style line is formed. The apparatus and method achieve sharper radius style lines in metals like aluminum, advanced high strength steel, and ultra-high strength steel than a traditional hard surface die set can achieve.

Abstract: An electrode assembly for electro-hydraulic forming tool in which the insulation sleeve is assembled over an electrode rod. The insulation sleeve has a deflection surface that is beveled or oriented at an angle relative to the axis of the electrode rod. The electrode assembly may include a replaceable conical receptacle that facilitates placement of an electrode tip an insulation sleeve tip. An electrode tip profile that is shaped to minimize erosion caused by discharge of the electro-hydraulic forming machine.

Abstract: An electrode assembly for electro-hydraulic forming tool in which the insulation sleeve is assembled over an electrode rod. The insulation sleeve has a deflection surface that is beveled or oriented at an angle relative to the axis of the electrode rod. The electrode assembly may include a replaceable conical receptacle that facilitates placement of an electrode tip an insulation sleeve tip. An electrode tip profile that is shaped to minimize erosion caused by discharge of the electro-hydraulic forming machine.

Abstract: A tool for modifying a workpiece by either trimming or joining the workpiece. The tool is an electro-hydraulic tool that uses a pulse transmitted through a liquid to trim a workpiece or to join two thicknesses of metal together. A method of trimming the workpiece includes the steps of providing a high voltage discharge in a liquid that drives a workpiece into engagement with a cutting edge of a tool steel insert. A method of joining two or more thicknesses of metal together includes the step of creating a high voltage discharge through an electrode that accelerates one panel or thickness of metal into a second panel that is held stationary by a backing plate while the first thickness of metal is accelerated into the second thickness of metal.

Abstract: One or more electro-hydraulic forming tools are operated by a press and provide formed parts to a trimming operation. A locking mechanism holds the die against the chamber during the electro-hydraulic forming (EHF) discharge. The lock may be a pin or clamp. One method of manufacturing an article includes providing three EHF tools that feed a single trimming press on a line. An alternative embodiment discloses a single EHF tool that supplies parts on a production line to an electro-hydraulic (EH) trimming tool. An electro-hydraulic pulse generator may be used to provide a stored charge to the EHF tool and the EH trimming tool.

Abstract: A method and apparatus for forming a flange on a panel. The flange is formed under compression to provide a reduced outside radius on the finished flange. The flange may be formed about an outside corner with a distal edge of the flange being restricted by a limiting edge formed on a die. Alternatively, the flange may be formed into an inside corner of a die with a compressive force being exerted on a distal edge of the flange by a compressing tool while a forming tool forms the flange with a reduced final outside radius.