Patent ID: 8534106

Claim:
A machine for forming a blank comprising: a hydro-mechanical forming tool that includes a punch received within a blank holder; a draw chamber that contains a body of liquid that partially fills the draw chamber, wherein the draw chamber defines an air space above the liquid and below a blank receiving surface, wherein the blank is supported by the blank holder, wherein the blank is spaced from the body of liquid, and wherein the punch forms the blank before the blank is driven into contact with the body of the liquid; an electro-hydraulic forming chamber provided with in the draw chamber; an electro-hydraulic discharge system that is discharged in the liquid contained in the draw chamber after the punch draws the blank into the draw chamber and into contact with the liquid, wherein actuation of the discharge system forms the blank against the punch; and wherein the draw chamber includes a lower ring that defines a main liquid cavity in which a first portion of the body of liquid is contained, a side wall is part of the lower ring and a peripheral liquid chamber defined by the lower ring inboard of the blank receiving surface, outboard of the draw chamber, and by the blank, wherein the blank forms a seal with the side wall as the blank is formed by the punch into the draw chamber, wherein a second portion of the liquid is supplied to the peripheral liquid chamber under pressure that supports the blank in the area where the blank is formed into the draw chamber and wherein the blank seals the liquid in the peripheral liquid chamber from the main liquid cavity.