Patents by Inventor Paul E. Krajewski

Paul E. Krajewski 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).

  • Publication number: 20080083426
    Abstract: Chemical method of cleaning metallic residue from forming tools utilizing the application of a caustic material including base or mild acid to the tool for a short period of time. The caustic material is held in substantially fixed relation for a period of time to dislodge the metallic residue followed by neutralization or removal.
    Type: Application
    Filed: October 10, 2006
    Publication date: April 10, 2008
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Anil K. Sachdev, Paul E. Krajewski
  • Publication number: 20080078225
    Abstract: Improved lubricant system useful in metal forming processes. The lubricant formulations contain boron nitride lubricant with graphite additions. These formulations enhance lubricity while maintaining good adherence at elevated temperatures.
    Type: Application
    Filed: September 28, 2006
    Publication date: April 3, 2008
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Michael D. Hanna, Paul E. Krajewski, James G. Schroth
  • Patent number: 7290423
    Abstract: Various embodiments of roller hemming apparatus and methods are disclosed including one wherein multiple rollers are carried on a single mount to hem a flange in a single pass, another including induction heating and air quenching means movable with a roller to anneal the flange just prior to hem forming, and another in which friction from a rotatably driven roller heats the flange to reduce bending stresses during hemming of the flange.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: November 6, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: John E. Carsley, Wayne W. Cai, Gary A. Kruger, Paul E. Krajewski, Yang-Tse Cheng
  • Patent number: 7260972
    Abstract: Sheet metal parts having significantly strained portions, such as aluminum alloy body panels, can be formed by a sequence of steps comprising preform shape stamping, preform annealing and final shape stamping. The shape of the desired part is analyzed to identify portions of the geometry that cannot be formed in a single stamping step without exceeding the straining limit of the metal. A preform shape is determined in which a substantial amount of strain is stamped without tearing and the preform is annealed to re-soften the strained areas and a final stamping step completes development of the final part shape.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: August 28, 2007
    Assignee: General Motors Corporation
    Inventor: Paul E. Krajewski
  • Patent number: 7165435
    Abstract: Work hardened sheets of formable metal are annealed by thermal conduction and heated to a forming temperature. In a preferred embodiment, the sheet is placed on a flat surface of a heated lower platen to partially heat and soften the sheet and an opposing heated upper platen is brought close enough to the sheet to contribute heat but not to constrain the sheet as it expands. The platens are then both brought close to the sheet to heat it to its forming temperature largely by thermal conduction.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: January 23, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: James G. Schroth, Richard H. Hammar, Paul E. Krajewski, Leonard L. Pollum, Susan Elizabeth Hartfield-Wunsch
  • Patent number: 7100259
    Abstract: Disclosed is a method of forming metallic composite structures The method utilizes superplastic and quickplastic formation methodologies in conjunction with the use of appended engineered metallic foams to provide energy absorbing materials.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: September 5, 2006
    Assignee: General Motors Corporation
    Inventors: Arianna T Morales, Paul E Krajewski
  • Patent number: 6994350
    Abstract: The present invention involves a method to produce crush zones in aluminum structures using controlled application of retrogression heat treatment. Selected areas of a tubular rail are retrogression heat treated to locally lower the tensile yield strength. As a result, during a crash event, initial deformation is localized in the crush zone enabling the crush pattern to be designed directly into the structure.
    Type: Grant
    Filed: March 28, 2003
    Date of Patent: February 7, 2006
    Assignee: General Motors Corporation
    Inventors: Paul E. Krajewski, Alan (Aihua) A. Luo, Susan E. Hartfield-Wünsch, Patrick J. McNamara
  • Patent number: 6825442
    Abstract: A tailor welded blank for use in a fluid-forming operation includes a first sheet element having a physical characteristic with a first value and a second sheet element having the physical characteristic with a second value different from the first value. The first and second sheet elements are welded together at at least one weld region to form at least a portion of a tailor welded blank. When the tailor welded blank is processed in a fluid forming process, the first and second values of the physical characteristic result in said first and second sheet elements having approximately equal effective strength values such that said first and second sheet elements deform at an approximately equal rate during the fluid forming process and local thinning and failure initiation is reduced at the at least one weld region and throughout the first and second sheet elements.
    Type: Grant
    Filed: January 6, 2003
    Date of Patent: November 30, 2004
    Assignee: General Motors Corporation
    Inventors: James G. Schroth, Paul E. Krajewski
  • Publication number: 20040189049
    Abstract: The present invention involves a method to produce crush zones in aluminum structures using controlled application of retrogression heat treatment. Selected areas of a tubular rail are retrogression heat treated to locally lower the tensile yield strength. As a result, during a crash event, initial deformation is localized in the crush zone enabling the crush pattern to be designed directly into the structure.
    Type: Application
    Filed: March 28, 2003
    Publication date: September 30, 2004
    Inventors: Paul E. Krajewski, Alan (Aihua) A. Luo, Susan E. Hartfield-Wunsch, Patrick J. McNamara
  • Publication number: 20040129690
    Abstract: A tailor welded blank for use in a fluid-forming operation includes a first sheet element having a physical characteristic with a first value and a second sheet element having the physical characteristic with a second value different from the first value. The first and second sheet elements are welded together at at least one weld region to form at least a portion of a tailor welded blank. When the tailor welded blank is processed in a fluid forming process, the first and second values of the physical characteristic result in said first and second sheet elements having approximately equal effective strength values such that said first and second sheet elements deform at an approximately equal rate during the fluid forming process and local thinning and failure initiation is reduced at the at least one weld region and throughout the first and second sheet elements.
    Type: Application
    Filed: January 6, 2003
    Publication date: July 8, 2004
    Inventors: James G. Schroth, Paul E. Krajewski