Patents by Inventor David B. Crowhurst

David B. Crowhurst 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: 6081169
    Abstract: A conducting housing (to be closed by a lid) for a coaxial cable distribution network has a common port and one of an aerial or pedestal port. A motherboard carries an RF circuit and a transfer switch. In one setting of the transfer switch the RF circuit connects a coaxial pin at the common port with a coaxial pin at the pedestal port. In the other setting the common port pin is connected to the aerial port pin. When the aerial port is used on a rectangular housing, a transmission line forms part of the RF circuit between the motherboard and the aerial port. The transmission is preferably a central conductor spaced over most of its length by air from an outer conductor in the form of an inverted U enclosing the central conductor on three sides. Preferably a ground plane on the back of the motherboard connects to the transmission line outer conductor to provide a path entry in the housing at both ends for ground currents generated by signals in the RF path.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: June 27, 2000
    Assignee: J.E. Thomas Specialties Limited
    Inventors: Robert L. Romerein, David B. Crowhurst, Zdenek J. Nepovim, Kenneth W. Lynes
  • Patent number: 5834989
    Abstract: A conducting housing (to be closed by a lid) for a coaxial cable distribution network has a common port and one of an aerial or pedestal port. A motherboard carries an RF circuit and a transfer switch. In one setting of the transfer switch the RF circuit connects a coaxial pin at the common port with a coaxial pin at the pedestal port. In the other setting the common port pin is connected to the aerial port pin. When the aerial port is used on a rectangular housing, a transmission line forms part of the RF circuit between the motherboard and the aerial port. The transmission is preferably a central conductor spaced over most of its length by air from an outer conductor in the form of an inverted U enclosing the central conductor on three sides. Preferably a ground plane on the back of the motherboard connects to the transmission line outer conductor to provide a path entry in the housing at both ends for ground currents generated by signals in the RF path.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: November 10, 1998
    Assignee: J.E. Thomas Specialties Limited
    Inventors: Robert L. Romerein, David B. Crowhurst, Zdenek J. Nepovim, Kenneth W. Lynes
  • Patent number: 5828272
    Abstract: A conducting housing for use in a coaxial cable distribution system is of larger length than width and defines an RF signal path therein. A part of the RF signal path is the inner conductor of inner and outer approximately co-extensive conductors. The inner conductor except near its ends has only air separating it from the outer conductor. The outer conductor will usually be of a U-shape lying, in section, on three sides of the central conductor. The outer conductor may be structually combined with an insulating plate supporting the remainder of the RF circuit.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: October 27, 1998
    Assignee: J. E. Thomas Specialties Limited
    Inventors: Robert L. Romerein, David B. Crowhurst
  • Patent number: 5750929
    Abstract: A terminal assembly for a CATV RF circuit is located on a circuit board with a slot open towards a port through which projects a coaxial cable pin. The board is located below the pin and the slot allows travel of the board vertically therepast. A conducting blade connected to RF circuitry on the board projects over and parallel to the pin and a yoke, slidable on the blade, slides from a retracted position where the board may be lifted past the pin and an extended position, where it encircles the pin and blade and clamps them together.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: May 12, 1998
    Assignee: J. E. Thomas Specialties Limited
    Inventors: Robert L. Romerein, David B. Crowhurst, Christopher A. Allinson
  • Patent number: 5638035
    Abstract: A conducting housing (to be closed by a lid) for a coaxial cable distribution network has a common port and one of an aerial or pedestal port. A motherboard carries an RF circuit and a transfer switch. In one setting of the transfer switch the RF circuit connects a coaxial pin at the common port with a coaxial pin at the pedestal port. In the other setting the common port pin is connected to the aerial port pin. When the aerial port is used on a rectangular housing, a transmission line forms part of the RF circuit between the motherboard and the aerial port. The transmission is preferably a central conductor spaced over most of its length by air from an outer conductor in the form of an inverted U enclosing the central conductor on three sides. Preferably a ground plane on the back of the motherboard connects to the transmission line outer conductor to provide a path entry in the housing at both ends for ground currents generated by signals in the RF path.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: June 10, 1997
    Assignee: J. E. Thomas Specialties Limited
    Inventors: Robert L. Romerein, David B. Crowhurst, Zdenek J. Nepovim, Kenneth W. Lynes
  • Patent number: 5635881
    Abstract: A conducting housing for use in a coaxial cable distribution system is of larger length than width and defines an RF signal path therein. A part of the RF signal path is the inner conductor of inner and outer approximately coextensive conductors. The inner conductor except near its ends has only air separating it from the outer conductor. The outer conductor will usually be of a U-shape lying, in section, on three sides of the central conductor. The outer conductor may be structally combined with an insulating plate supporting the remainder of the RF circuit.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: June 3, 1997
    Assignee: J.E. Thomas Specialties Limited
    Inventors: Robert L. Romerein, David B. Crowhurst
  • Patent number: 5220297
    Abstract: A transmission line transformer device has a body of magnetically permeable material defining two passages each of which is adapted to receive a pair of conductors which extend up one passage, between the passages and down the other passage. The conductor insulation and spacing are adapted to provide a predetermined characteristic impedance across the bandwidth and the body dimensions and passage spacing are adapted to provide isolation between the conductors and selected impedance across the bandwidth.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: June 15, 1993
    Assignee: J.E. Thomas Specialties Limited
    Inventor: David B. Crowhurst