摘要 |
An electric vacuum valve comprising a body including a chamber having a first passage adapted to be connected to a source of vacuum, a valve seat in the chamber, a bi-metallic disc associated with the valve seat and operable to close the first passage and a second passage to the exterior of said body. A PTC disc is positioned in the chamber adjacent the bi-metallic disc and includes a first terminal connected to one side thereof and extending exteriorly of the body and a second terminal connected to the other side thereof and extending externally of the body such that heat from the PTC disc functions to radiate toward the bi-metallic disc when power is applied to said terminals to cause the bi-metallic disc to seat against the valve seat and when power is terminated, the bi-metallic disc cools and moves away from the valve seat.
|