Patent ID: 7483252

Claim:
A voltage suppression device for suppressing voltage surges in an electrical circuit said device comprised of: a voltage sensitive element having a first surface and a second surface and a predetermined voltage rating across said first and second surfaces, said voltage sensitive element increasing in temperature as voltage applied across said first and second surfaces exceeds said voltage rating; a first terminal having one end electrically connected to said first surface of said voltage sensitive clement and another end electrically connectable to a first line of the electrical circuit; a thermal element electrically connected to said second surface of said voltage sensitive element, said thermal element being an electrically conductive solid at room temperature and having a predetermined softening temperature; a second terminal having one end in electrical connection with said second surface of said voltage sensitive element and another end electrically connectable to a second line of the electrical circuit, said voltage sensitive element sensing the voltage drop between said first and second lines of the electrical circuit, said second terminal being maintained in electrical contact with said voltage sensitive element by said thermal element and being biased away therefrom, wherein said second terminal moves away from electrical contact with said voltage sensitive element and breaks a first electrical current path if an over-voltage condition sensed by said voltage sensitive element exceeds the voltage rating of said voltage sensitive element and causes said voltage sensitive element to heat said thermal element beyond its softening point; a fuse element having one end in electrical connection with said second surface of said voltage sensitive element and another end electrically connectable to the second line of the electrical circuit, said fuse element located along a second electrical current path parallel to the first electrical current path, wherein the second electrical current path is broken when the fuse element melts; and a housing enclosing said voltage sensitive element, said one ends of said first and second terminals, and said thermal element.