×

Self-healing parallel heating tape

  • US 4,891,500 A
  • Filed: 09/02/1988
  • Issued: 01/02/1990
  • Est. Priority Date: 09/05/1987
  • Status: Expired due to Term
First Claim
Patent Images

1. A parallel heating tape, comprising:

  • (a) two electrical power conductors extending generally alongside but spaced apart from one another;

    (b) a plurality of heating elements extending between and being electrically connected to each of the two power conductors along the length of tape;

    (c) the heating elements each being thinner and of higher resistance than the power conductors and providing a current path from one of the power conductors to the other whereby the heating elements dissipate heat;

    (d) a temperature monitoring conductor extending alongside one of the power conductors but being separated from the respective power conductor by a substance which electrically insulates the temperature monitoring conductor from the power conductor when the temperature is below one of the specified temperatures and a temperature within a transition temperature range; and

    (e) the substance providing a current path between the power conductor and the temperature monitoring conductor when the temperature is above the respective one of the specified temperature and a temperature within the transition temperature range, and the substance again insulating the power conductor from the temperature monitoring conductor when the temperature falls below the respective specified temperature or a temperature within the transition temperature range.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×