Hermetically sealed switch assembly

In a switch assembly including a base member having a contact receiving, cavity open at the top and defined by a floor that is laterally enclosed by side wall means, first terminal means in the cavity adapted for electrical connection to outside circuitry, second terminal means in the cavity adapted for electrical connection to outside circuitry having a resilient contact blade portion with an end spaced from said first terminal means, said contact blade portion being moveable between a normally open position wherein said end is spaced from said first terminal means and a closed position wherein said end contacts said first terminal means, a cover mounted on said base member having means for mounting an actuator assembly thereon, and an actuator assembly mounted on the mounting means of the cover actuable for moving said contact blade portion between its open and closed positions, the improvement comprising:

• a thin, stretchable, resilient, impermeable sealing gasket on said base member which overlies said cavity;
• said cover engaging the periphery of said gasket, and including interengaging means cooperating with said base member to lock said cover and gasket to said base member to form a hermetic seal over said cavity;
• and
• said actuator assembly including a push member mounted for general up and down movement against the gasket, said actuator assembly being moveable between an off position wherein the push member is in an up position and said contact blade portion is in the open position and an on position wherein the push member is moved against the resilient force of the gasket to push the contact blade portion to the closed position.