The present invention concerns a device for pulsed electric discharge in a liquid comprising a control module configured to control a voltage generator such that the voltage generator applies a predetermined heating voltage setpoint between electrodes during a heating period until a pulsed electric discharge is obtained between the electrodes, in order to measure the breakdown voltage during the pulsed electric discharge, in order to estimate the quantity of energy supplied to the liquid during the heating period, referred to as the quantity of heating energy, from the predetermined heating voltage setpoint and the measured breakdown voltage, and in order to determine a new heating voltage setpoint to apply between the electrodes of the at least one pair of electrodes at the next pulsed electric discharge based on the estimated quantity of heating energy and a predefined breakdown voltage setpoint.

The present invention concerns a device for pulsed electric discharge in a liquid comprising a control module configured to control a voltage generator such that the voltage generator applies a predetermined heating voltage setpoint between electrodes during a heating period until a pulsed electric discharge is obtained between the electrodes, in order to measure the breakdown voltage during the pulsed electric discharge, in order to estimate the quantity of energy supplied to the liquid during the heating period, referred to as the quantity of heating energy, from the predetermined heating voltage setpoint and the measured breakdown voltage, and in order to determine a new heating voltage setpoint to apply between the electrodes of the at least one pair of electrodes at the next pulsed electric discharge based on the estimated quantity of heating energy and a predefined breakdown voltage setpoint.

An improved electro-hydraulic clinching system involves generating, through a high potential electric shock, a forceful wave in a fluid such as water, and applying the force of the wave to a sheet of metal. The force of the wave results in deforming the sheet and making the sheet material move through a hole in a second sheet adjacent to the first sheet, thus joining the two sheets. In an alternative implementation, in which neither sheet includes an opening, the force of the wave moves both sheets simultaneously, thereby causing them to join together at the point of impact.

An electrohydraulic forming device for forming a blank of material includes: an electrohydraulic forming chamber, at least one central electrode extending in a so-called longitudinal direction and comprising a first end arranged inside the electrohydraulic forming chamber, a body provided with a bore for introducing each central electrode into the electrohydraulic forming chamber, the electrohydraulic forming chamber being partially formed by said body, a mould, and at least one peripheral electrode electrically insulated from each central electrode, arranged at a distance from and around the end of a central electrode, and extending in a transverse plane relative to said central electrode.

An electrohydraulic forming device for forming a blank of material includes: an electrohydraulic forming chamber, at least one central electrode extending in a so-called longitudinal direction and comprising a first end arranged inside the electrohydraulic forming chamber, a body provided with a bore for introducing each central electrode into the electrohydraulic forming chamber, the electrohydraulic forming chamber being partially formed by said body, a mould, and at least one peripheral electrode electrically insulated from each central electrode, arranged at a distance from and around the end of a central electrode, and extending in a transverse plane relative to said central electrode.

A hybrid method for forming a material blank includes placing a material blank to be deformed between a die and a blank-holder. The material blank is deformed by stamping using at least one punch in order to obtain a pre-stamped material blank. A cavity, wherein, on one hand, the at least one punch having pre-stamped the material blank and, on the other, at least one pair of electrodes are located, is filled with liquid. The pre-stamped material blank is placed in contact with the liquid of the cavity, and at least one electrical discharge is generated between the at least one pair of electrodes in such a way as to deform the pre-stamped material blank against the die.

A hybrid method for forming a material blank includes placing a material blank to be deformed between a die and a blank-holder. The material blank is deformed by stamping using at least one punch in order to obtain a pre-stamped material blank. A cavity, wherein, on one hand, the at least one punch having pre-stamped the material blank and, on the other, at least one pair of electrodes are located, is filled with liquid. The pre-stamped material blank is placed in contact with the liquid of the cavity, and at least one electrical discharge is generated between the at least one pair of electrodes in such a way as to deform the pre-stamped material blank against the die.

An electrohydraulic forming chamber to form a workpiece. The chamber includes a discharge frame that has an inner wall which delimits a discharge space provided to hold a volume of fluid, a female mold having a forming space which includes an impression configured to be complementary to the shape of the workpiece after deformation, and an electrohydraulic discharge system. The workpiece is placed between the discharge space and the forming space before the electrohydraulic discharge system is activated. Upon activation of the electrohydraulic discharge system, the workpiece is catapulted against the impression in the forming space and is deformed accordingly. All or part of the inner wall is provided with a non-metal coating.

An electrohydraulic forming chamber to form a workpiece. The chamber includes a discharge frame that has an inner wall which delimits a discharge space provided to hold a volume of fluid, a female mold having a forming space which includes an impression configured to be complementary to the shape of the workpiece after deformation, and an electrohydraulic discharge system. The workpiece is placed between the discharge space and the forming space before the electrohydraulic discharge system is activated. Upon activation of the electrohydraulic discharge system, the workpiece is catapulted against the impression in the forming space and is deformed accordingly. All or part of the inner wall is provided with a non-metal coating.

A method for electrohydraulically forming a blank of material includesa blank of material to be deformed is placed between a mould and a blank holder,a cavity containing electrodes is filled with liquid to a predetermined liquid level,the blank of material is placed in contact with the liquid in the cavity,a first electric discharge is generated between at least two electrodes so as to deform the blank of material against the mould,the mould is brought nearer to the electrodes by moving the mould so as to reduce the distance between the electrodes and the blank of material to be deformed after the first electric discharge has been generated,at least one other electric discharge is generated between at least two electrodes so as to deform the blank of material against the mould.