Patent ID: RE42319

Claim:
A disposable 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 element and another end connectable to a ground or neutral line of an 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 connectable to an electrical power line of an electrical circuit, said voltage sensitive element sensing the voltage drop between said electrical power line and ground or neutral line, 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 said 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; an arc shield movable from a first position wherein said arc shield allows contact between said second terminal and said voltage sensitive element to a second position wherein said shield is disposed between said second terminal and said voltage sensitive element when said second terminal moves from electrical contact with said voltage sensitive element; and a housing enclosing said voltage sensitive element, said one ends of said first and second terminals, said thermal element and said arc shield ; and a wall contained within the housing for separating the voltage sensitive element from the arc shield over a substantial portion of the length of the arc shield .