Patent · US Expired

Method and apparatus for regulating preselected loads on forming dies

US4420958A · kind A · utility

12Cited by
12References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 17, 1981
Grant dateDec 20, 1983
Priority date
Expiry dateDec 17, 2001

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB21D53/045
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

An improvement to an apparatus for and method of making structures from at least one workpiece is disclosed. The prior art apparatus and method comprised a pair of dies which were clamped about the periphery of the at least one workpiece creating a gap therebetween. A pair of non-inflatable platens were then used to apply a force against the pair of dies further clamping the workpiece in place. The die assembly and workpiece were then heated to forming temperatures and thereafter the workpiece was formed within the pair of dies by fluid under pressure. Typically the forming was Superplastic Forming or Superplastic Forming/Diffusion Bonding. The improvement to the apparatus and method comprises providing an inflatable platen between one of the dies and one of the non-inflatable platens, adapted to regulate the force applied by said pair of dies to said at least one workpiece. A sensor, mounted within the gap is adapted to sense changes in the dimensions of the actual gap and provide a first output signal proportional thereto during the forming of the structure. A signal generator is provided for producing a second output signal proportional to a preferred gap dimension that is produ…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.