Patents by Inventor David E. Gay

David E. Gay 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).

  • Patent number: 5637402
    Abstract: Moldable ferromagnetic particles and method of making a magnetizable molding therefrom. The ferromagnetic particles are spray-coated with a slurry comprising insoluble thermoplastic particles suspended in a solution of a soluble polymer to produce a coating on the ferromagnetic particles which comprises a majority of the insoluble thermoplastic particles embedded in a lesser amount of a binder polymer. When compression molded, the insoluble thermoplastic particles form a continuous matrix for the ferromagnetic particles.
    Type: Grant
    Filed: April 23, 1996
    Date of Patent: June 10, 1997
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5629092
    Abstract: A mass of ferromagnetic particles having a lubricous shell comprising a plurality of organic lubricant particles embedded in a film of a thermoplastic binder.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: May 13, 1997
    Assignee: General Motors Corporation
    Inventors: David E. Gay, Howard H.-D. Lee
  • Patent number: 5607525
    Abstract: End segments of a Lundell-type rotor for an AC generator, wherein the base and the teeth portions thereof are compaction molded separately and subsequently joined together and sintered.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: March 4, 1997
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5595609
    Abstract: A method for stress relieving a compression molded magnetic body is provided for purposes of enhancing the magnetic permeability of the magnetic body. The method involves encapsulating ferromagnetic particles with a thermoplastic polymer coating selected from the group consisting of polybenzimidazole and polyimides having heat deflection temperatures of at least about 400.degree. C. which are capable of withstanding elevated temperatures for a duration which is sufficient to anneal the magnetic body formed from the coated metal particles. As a result, the stresses induced in the magnetic core by the compression molding process can be relieved without detriment to the mechanical properties and magnetic characteristics of the magnetic core.
    Type: Grant
    Filed: November 24, 1995
    Date of Patent: January 21, 1997
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5591373
    Abstract: A mass of ferromagnetic particles moldable into stable, high strength, magnetic cores useful in thermally and chemically hostile environments comprising an iron core and a continuous layer of polyetherimide, polyethersulfone or polyamideimide spray coated onto the surface of each particle. A method of preheating and molding the particles is disclosed.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: January 7, 1997
    Assignee: General Motors Corporation
    Inventors: Robert W. Ward, David E. Gay
  • Patent number: 5589010
    Abstract: A compression molded soft magnetic core comprising annealed soft ferromagnetic metal particles bonded together in a thermoplastic polymer matrix having a heat deflection temperature greater than about 400.degree. C. and selected from the group consisting of polybenzimidazole and polyimides.
    Type: Grant
    Filed: November 24, 1995
    Date of Patent: December 31, 1996
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5567746
    Abstract: Moldable ferromagnetic particles and method of making a magnetizable molding therefrom. The ferromagnetic particles are spray-coated with a slurry comprising insoluble thermoplastic particles suspended in a solution of a soluble polymer to produce a coating on the ferromagnetic particles which comprises a majority of the insoluble thermoplastic particles embedded in a lesser amount of a binder polymer. When compression molded, the insoluble thermoplastic particles form a continuous matrix for the ferromagnetic particles.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: October 22, 1996
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5563001
    Abstract: A polymeric coating material is provided for coating powdered materials, and more particularly, for coating powdered metals which are compression molded to form magnetic cores. The preferred polymeric materials are polybenzimidazole, an aromatic polyamide such as polyphthalamide, and appropriate polyimides which, when properly applied to metal particles to form a magnetic core, are characterized as having a sufficiently high heat deflection temperature of at least about 270.degree. C., so as to prevent the degradation of the mechanical and magnetic properties of the magnetic core at exposure at elevated temperatures. Each of these preferred coating materials is characterized by excellent mechanical properties, chemical resistance and dielectric characteristics within this temperature range.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: October 8, 1996
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5472661
    Abstract: Method of distributing and retaining insoluble additive particles uniformly throughout a mass of moldable metal particles. The additive particles are suspended in a solution of a polymeric binder and spray-coated onto the metal particles. When the solvent evaporates, the additives remain glued to the metal particles by the binder.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: December 5, 1995
    Assignee: General Motors Corporation
    Inventor: David E. Gay
  • Patent number: 5395695
    Abstract: Oxidation-resistant, individually encapsulated neodymium-iron-boron permanent magnet particles are provided. The particles are individually coated with, preferably, three distinct organic layers and are useful for the subsequent formation of a molded permanent magnet article. The first coating is an antioxidant layer employed for the retardation of oxidation of the coated particle. The second intermediate layer consists of an appropriate thermosetting epoxy to provide the adhesion required during subsequent molding of the particles. The third and outermost layer consists of polystyrene and is employed to keep the particles free flowing, since the epoxy layer may be tacky after deposition, thereby hindering the free flowability of the particles. The coatings are applied sequentially using fluidized bed coating techniques. The encapsulated particles can then be molded and appropriately cured. In addition, the encapsulated particles exhibit enhanced oxidation resistance, including at elevated temperatures.
    Type: Grant
    Filed: August 19, 1993
    Date of Patent: March 7, 1995
    Assignee: General Motors Corporation
    Inventors: Jon C. Shain, David E. Gay
  • Patent number: 5271891
    Abstract: A polymeric coating material is provided for coating powdered materials and, more particularly, for coating powdered metals formed into parts and sintered, such as to form magnetic cores. The thermoplastic material is polyphenylene oxide which, when properly applied to metal particles to form a magnetic core, is characterized by being sufficiently volatile so as to prevent the formation of contaminants or voids within the sintered article which would be detrimental to the physical properties of the sintered article. Moreover, polyphenylene oxide provides sufficient lubrication and adhesion between adjacent metal particles during an initial compaction process so as to sustain the desired shape of the molded article and maximize metal particle density without the use of additional lubricants, thereby preventing the formation of additional contaminants and/or voids within the resultant sintered article from these lubricants.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: December 21, 1993
    Assignee: General Motors Corporation
    Inventors: David E. Gay, Robert W. Ward
  • Patent number: 5272008
    Abstract: Oxidation-resistant, individually encapsulated neodymium-iron-boron permanent magnet particles are provided. The particles are individually coated with, preferably, three distinct organic layers and are useful for the subsequent formation of a molded permanent magnet article. The first coating is an antioxidant layer employed for the retardation of oxidation of the coated particle. The second intermediate layer consists of an appropriate thermosetting epoxy to provide the adhesion required during subsequent molding of the particles. The third and outermost layer consists of polystyrene and is employed to keep the particles free flowing, since the epoxy layer may be tacky after deposition, thereby hindering the free flowability of the particles. The coatings are applied sequentially using fluidized bed coating techniques. The encapsulated particles can then be molded and appropriately cured. In addition, the encapsulated particles exhibit enhanced oxidation resistance, including at elevated temperatures.
    Type: Grant
    Filed: March 16, 1992
    Date of Patent: December 21, 1993
    Assignee: General Motors Corporation
    Inventors: Jon C. Shain, David E. Gay
  • Patent number: 5211896
    Abstract: A mass of ferromagnetic particles moldable into stable, high strength, magnetic cores useful in thermally and chemically hostile environments comprising an iron core and a continuous layer of polyetherimide, polyethersulfone or polyamideimide spray coated onto the surface of each particle. A method of preheating and molding the particles is disclosed.
    Type: Grant
    Filed: June 7, 1991
    Date of Patent: May 18, 1993
    Assignee: General Motors Corporation
    Inventors: Robert W. Ward, David E. Gay
  • Patent number: 4146282
    Abstract: A vehicle battery accessory apparatus utilizes a first pair of electrical conductors, having the first ends thereof provided with clamps suitable for convenient coupling to the terminals of the battery, a storage reel upon which the major length of a second pair of electrical conductors may be stored, and a brush and commutating arrangement to electrically couple the second pair of electrical conductors and the first pair of electrical conductors together, the second pair of electrical conductors being provided with electrical connectors of the clamping type and an insulating bar having a pair of lugs thereon such that the bar is provided with lugs for retaining the electrical clamping connectors in a stored non-shorting condition when the apparatus is not in use.
    Type: Grant
    Filed: September 6, 1977
    Date of Patent: March 27, 1979
    Inventor: David E. Gay