Patents Assigned to Bowthorpe Emp Limited
  • Method and apparatus for manufacturing a surge arrester
    Patent number: 5003689
    Abstract: A distribution class surge arrester comprises a core formed of distributed zinc oxide varistor blocks, aluminum blocks acting as heat sinks and as spacers providing voltage grading and required arcing distances, and terminal blocks held in face-to-face contact by means of a glass reinforced epoxy shell which is formed by winding a pre-preg onto the assembled blocks and thermally curing under mold pressure within an evacuated mold. The core is housed within a polymeric shedded housing which is formed by shrinking a heat-shrink shedded sleeve onto the core with a sealant provided in the interface of the core and the sleeve, and end caps are sealed to the ends of the structure thus formed.
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: April 2, 1991
    Assignee: Bowthorpe EMP Limited
    Inventors: Rodney M. Doone, Henry J. Colbert
  • Use of a surge arrester as a combined surge arrester and support insulation
    Patent number: 4992906
    Abstract: A distribution class surge arrester having a core formed of distributed zinc oxide varistor blocks, aluminum blocks acting as heat sinks and as spacers providing voltage grading and required arcing distances, and terminal blocks held in face-to-face contact by means of a glass reinforced epoxy shell which is formed by winding a pre-preg onto the assembled blocks and thermally curing under mold pressure within an evacuated mold. The core is housed within a polymeric shedded housing which is formed by shrinking a heat-shrink shedded sleeve onto the core with a sealant provided in the interface of the core and the sleeve, and end caps are sealed to the ends of the structure thus formed.
    Type: Grant
    Filed: June 15, 1989
    Date of Patent: February 12, 1991
    Assignee: Bowthorpe EMP Limited
    Inventors: Rodney M. Doone, Henry J. Colbert
  • Electrical surge arrester/diverter having a heat shrink material outer housing
    Patent number: 4851955
    Abstract: A distribution class surge arrester comprises a core formed of distributed zinc oxide varistor blocks, aluminum blocks acting as heat sinks and as spacers providing voltage grading and required arcing distances, and terminal blocks held in face-to-face contact by means of a glass reinforced epoxy shell which is formed by winding a pre-preg onto the assembled blocks and thermally curing under mold pressure within an evacuated mold. The core is housed within a polymeric shedded housing which is formed by shrinking a heat-shrink shedded sleeve onto the core with a sealant provided in the interface of the core and the sleeve, and end caps are sealed to the ends of the structure thus formed.
    Type: Grant
    Filed: October 29, 1986
    Date of Patent: July 25, 1989
    Assignee: Bowthorpe EMP Limited
    Inventors: Rodney M. Doone, Henry J. Colbert
  • Electrical surge protection
    Patent number: 4720760
    Abstract: A mains electrical plug incorporates a zinc oxide non-linear resistor device (10) in the form of a circular zinc oxide disc having three electrode portions (2) provided on one face and contacting the earth, neutral and live pins (5) of the plug and a single electrode (3) on its other face, the device (10) thereby providing surge protection to the three electrical circuits provided within the plug.
    Type: Grant
    Filed: July 24, 1985
    Date of Patent: January 19, 1988
    Assignee: Bowthorpe Emp Limited
    Inventor: Tom Starr