Pressure responsive liquid level pump control

Claim 2

A pressure responsive liquid level pump control comprising a housing, a switch, having an operating force, for connection to a source of electrical energy and a pump, means controlling the actuation and deactuation of said switch, a pressure responsive diaphragm means, having two sides and including a single diaphragm, mounted in said housing with one said side engaging and coacting with said means for controlling the actuation and deactuation of said switch, and an annular restricting washer having a central opening of predetermined area contiguous with said one side of said diaphragm means and restricting movement of said diaphragm means in a direction to actuate said switch, said switch operating force biasing said diaphragm means in a direction away from said restricting washer, adjustable, resilient preloading means engaging the other side of said diaphragm means and biasing said diaphragm means in a direction to actuate said switch, and means connecting said housing on said other side of said diaphragm means to a liquid container whereby changes in the level of the liquid in said container vary the pressure acting on said other side of said diaphragm means.

Claim 3

A pump control according to claim 1 in which said adjustable, resilient preloading means comprises a compression spring having two ends, one of which engages said diaphragm means.

Claim 4

A pump control according to claim 2 including an adjustable seat for said spring at the end thereof remote from said diaphragm means.

Claim 5

A pump control according to claim 1 wherein said housing comprises a switch chamber and a pressure chamber, said switch being located in said switch chamber, said diaphragm means being located in said pressure chamber.

Claim 6

A pump control according to claim 4 wherein said pressure chamber is divided by said diaphragm means into a liquid level pressure chamber and an atmospheric pressure chamber.

Claim 7

A pump control according to claim 5 wherein said adjustable, resilient preloading means is located in said liquid level pressure chamber.

Claim 8

A pump control according to claim 1 wherein said restricting washer comprises a flat, ringlike portion and a skirt portion depending in a smooth curve from said flat ringlike portion and defining said opening.

Claim 9

A pressure responsive, liquid level pump control comprising a housing, a switch, having an operating force, for connection to a source of electrical energy and a pump, means controlling the actuation and deactuation of said switch, a pressure responsive diaphragm means, having two sides and including a single diaphragm, mounted in said housing and having one said side engaging and coacting with said means for controlling the actuation and deactuation of said switch, said switch operating force biasing said diaphragm means in a direction to deactuate said switch, adjustable, resilient preloading means engaginG the other side of said diaphragm means and biasing said diaphragm means in a direction to actuate said switch, and means connecting said housing on the other side of said diaphragm means to a liquid container whereby changes in the level of the liquid in said container vary the pressure acting on said other side of said diaphragm means, said adjustable, resilient preloading means comprising a compression spring having two ends and an adjustable seat, one end of said spring engaging said diaphragm means and the other end of said spring engaging said adjustable seat.

Claim 10

A pressure responsive, liquid level pump control comprising a housing, a switch, having an operating force, for connection to a source of electrical energy and a pump, means controlling the actuation and deactuation of said switch, a pressure responsive diaphragm means, having two sides and including a single diaphragm, mounted in said housing and having one said side engaging and coacting with said means for controlling the actuation and deactuation of said switch, said switch operating force biasing said diaphragm means in a direction to deactuate said switch, adjustable, resilient preloading means engaginG the other side of said diaphragm means and biasing said diaphragm means in a direction to actuate said switch, and means connecting said housing on the other side of said diaphragm means to a liquid container whereby changes in the level of the liquid in said container vary the pressure acting on said other side of said diaphragm means, said adjustable, resilient preloading means comprising a compression spring having two ends and an adjustable seat, one end of said spring engaging said diaphragm means and the other end of said spring engaging said adjustable seat.