04967057 is referenced by 75 patents and cites 56 patents.

Individual electrically heated mats, self-regulated by use of an electrical element whose resistance varies proportionately with its temperature, used for covering walking areas to prevent accumulation of snow and ice. Each mat is provided with male and female electrical connections on the ends of short power cords to permit any number of mats to be chained together in electrical parallel and to be used to cover, for example, a flight of stairs by positioning one mat on each stair.

Title
Snow melting heater mats
Application Number
7/227109
Publication Number
4967057
Application Date
August 2, 1988
Publication Date
October 30, 1990
Inventor
James M Havard
12067 W. 62nd Ave., Arvada, 80004
CO, US
Ronald E Bayless
34 Gala Pl., Pagosa Springs, 81147
CO, US
Agent
Maxwell C Freudenberg
Kenton L Freudenberg
IPC
H05B 3/36
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