Patent ID: 7895890

Claim:
A liquid depth sensing and identification system, comprising: a liquid container having at least one peripheral wall and a floor; a gas delivery dip tube extending into the container, the dip tube having a lower portion and an open lower end spaced above the floor of the container, and an upper portion and an upper end disposed externally to the container; a pneumatic gas supply pump disposed externally to the container, the pump communicating pneumatically with the upper portion of the dip tube; a gas collector disposed concentrically about the lower portion of the dip tube, the gas collector having a lower edge disposed slightly above the open lower end of the dip tube; a collector outlet tube extending from the collector, the outlet tube having a lower portion disposed within the container and an upper portion disposed externally to the container; a liquid depth differential pressure sensor disposed externally to the container, the depth pressure sensor communicating pneumatically with the dip tube and with ambient pressure; a liquid quality differential pressure sensor disposed externally to the container, the quality pressure sensor communicating pneumatically with the dip tube and with the collector outlet tube; a pump controller disposed externally to the container, the controller communicating electrically with the pneumatic gas supply pump, the liquid depth differential pressure sensor, and the liquid quality differential pressure sensor; and a processor disposed externally to the container, the processor communicating electrically with the pump controller.