Patents by Inventor Andrew B. Lehnert

Andrew B. Lehnert has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Molding process for multiple molds
    Patent number: 5234332
    Abstract: Molding press apparatus (20) for simultaneously operating a plurality of molds (M) having multiple mold parts (M1, M2) including, a framework (25), first and second platen assemblies (U,L) supported by the framework for carrying the mold parts of the molds, a third platen assembly (I) interposed between the first and second platen assemblies for mounting mating mold parts in opposed relation to the mold parts carried by the first and second platen assemblies, a drive assembly (80) for simultaneously moving the first and second platen assemblies relative to the third platen assembly for opening and closing the molds. Loading and unloading apparatus (150) may be provided for simultaneously transporting preformed fiber reinforcements (R) to the molds and for transporting molded parts (P) away from the molds associated with the platen assemblies.
    Type: Grant
    Filed: April 1, 1991
    Date of Patent: August 10, 1993
    Assignee: The Dow Chemical Company
    Inventors: Mark S. Hoenke, Andrew B. Lehnert, Warren L. Clark
  • Apparatuses and methods for incorporating blowing agents into liquids for the production of polymer foams and for measuring the volumetric expansion potential of mixtures thereof
    Patent number: 5154088
    Abstract: Apparatus (10, 180, 260, 270) for incorporating blowing agents into a liquid material provides a high pressure liquid storage and mixing tank (20, 181, 261, 271) containing a mixture of liquid material (M) under pressure; means for delivering (59, 220, 232, 285) a pre-determined quantity of at least one blowing agent into the mixture in minute bubbles or droplets having an average diameter of from about less than 0.2 micron up to about 100 microns; and means for uniformly distributing (60, 110, 237, 276) the blowing agent throughout the liquid material.
    Type: Grant
    Filed: June 4, 1991
    Date of Patent: October 13, 1992
    Assignee: The Dow Chemical Company
    Inventors: Andrew B. Lehnert, Mark S. Hoenke, Henri J. M. Gruenbauer
  • Apparatuses and methods for incorporating blowing agents into liquids for the production of polymer foams and for measuring the volumetric expansion potential of mixtures thereof
    Patent number: 5119668
    Abstract: Apparatus (10) for incorporating blowing agents into a liquid material provides a high pressure liquid storage and mixing tank (20) containing a mixture of liquid material (M) under pressure; means for delivering (59) a pre-determined quantity of at least one blowing agent into the mixture in minute bubbles having an average diameter of from about less than 0.5 micron up to about 100 microns; and means for uniformly distributing (60) the blowing agent throughout the liquid material. Apparatus (100) for measuring the volumetric expansion potential of a mixture of blowing agent and liquid material is also provided.
    Type: Grant
    Filed: July 24, 1990
    Date of Patent: June 9, 1992
    Assignee: The Dow Chemical Company
    Inventors: Andrew B. Lehnert, Henri J. M. Gruenbauer