초록 ▼

A bilge pump switch sensing the presence of bilge water by measuring the density of water by using an ultrasonic field penetrating the water, the field extending through the housing of the switch. Thus the internal elements of the switch are isolated from any contact with the water. The ultrasonic f

A bilge pump switch sensing the presence of bilge water by measuring the density of water by using an ultrasonic field penetrating the water, the field extending through the housing of the switch. Thus the internal elements of the switch are isolated from any contact with the water. The ultrasonic field detecting the presence of water activates sensing means in said switch housing to activate the pump, delay means being provided against false pump starts due to wave action as caused by a rocking boat.

대표청구항 ▼

An automatic bilge pump control device in connection with a bilge pump, having in combination a sensor plate, an oscillator injecting an alternating wave signal into a balanced voltage divider comprising a passive and active pair of detectors outputting identical square wave signals, a resistor, the

An automatic bilge pump control device in connection with a bilge pump, having in combination a sensor plate, an oscillator injecting an alternating wave signal into a balanced voltage divider comprising a passive and active pair of detectors outputting identical square wave signals, a resistor, the passive one of said detectors being grounded through said resistor, the active one of said detectors being in circuit with said sensor plate and its square wave signal being inverted 180°relative to said other detector, a phase shift detecting integrating transistor in circuit with said voltage divider having said wave signals coupled thereto, an integrating capacitor charged by said integrating transistor in direct proportion to any phase shifting detected, said phase shifting being responsive to the presence of bilge water in sufficiently close proximity to said sensor, and means responsive to said phase shifting detected causing said pump to operate.