Patents Assigned to Heindenreich & Harbeck
  • Method for blow molding a hollow plastic article having a concave base
    Patent number: 4035455
    Abstract: In a blow-moulding process, the base of a hollow plastics body is formed initially of convex configuration and then a portion of the base is deformed inwardly to provide a concave area surrounded by an annular support surface. Deformation of the base is controlled in response to an increase of pressure in the mold cavity after termination of venting thereof.
    Type: Grant
    Filed: September 16, 1975
    Date of Patent: July 12, 1977
    Assignee: Heindenreich & Harbeck
    Inventors: Otto Rosenkranz, Karl-Heinrich Seifert