Patents by Inventor Paul M. Boshell

Paul M. Boshell 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).

  • Electrical heater
    Patent number: 4721848
    Abstract: A self-limiting electrical heater comprising an elongate resistance heating element and a PTC resistor. The resistor is elongate and extends side-by-side with and along the length of the heating element so as to be responsive to the temperature of the entire length of the heating element. The heating element and resistor are connected in series, the resistor having a positive temperature coefficient such that its electrical resistance is substantially less than that of the heating element when at a normal operating temperature but increases rapidly when exposed to temperatures above the normal operating temperature.
    Type: Grant
    Filed: March 20, 1986
    Date of Patent: January 26, 1988
    Assignee: Heat Trace Limited
    Inventors: Neil S. Malone, Paul M. Boshell