초록 ▼

A multi-frequency ultrasonic liquid level gauging system includes a storage apparatus for storing a volume of liquid and a plurality of ultrasonic transducers. Each transducer introduces a distinct ultrasonic signal into storage apparatus and receives a reflected signal back. A circuit drives and re

A multi-frequency ultrasonic liquid level gauging system includes a storage apparatus for storing a volume of liquid and a plurality of ultrasonic transducers. Each transducer introduces a distinct ultrasonic signal into storage apparatus and receives a reflected signal back. A circuit drives and receives signals from the ultrasonic transducers. A processor calculates the liquid level at each of the locations of ultrasonic transducers based on the reflected signal received from each transducer. Transducers are connected in parallel, thereby allowing circuit to communicate to the transducers through a single conductive path. A method of measuring a liquid level in storage apparatus includes emitting a single drive signal to a plurality of ultrasonic signal sources, wherein each source is operable to transmit ultrasonic signals having unique frequencies. The ultrasonic signals are transmitted through liquid and each is reflected at the liquid surface. The reflected signals also have unique frequencies and are communicated to processor. The reflected signals are distinguished and the depth of the liquid level at various storage apparatus locations is calculated from each of the distinguished reflected signals. The depth of liquid is a function of the propagation time of each signal through the liquid.

대표청구항 ▼

[ What is claimed is:] [5.] An ultrasonic liquid level gauging system, comprising:a storage apparatus for storing a volume of liquid and a volume of gas above the liquid;a plurality of ultrasonic transducers connected in parallel, each transducer located for introducing a distinct ultrasonic signal

[ What is claimed is:] [5.] An ultrasonic liquid level gauging system, comprising:a storage apparatus for storing a volume of liquid and a volume of gas above the liquid;a plurality of ultrasonic transducers connected in parallel, each transducer located for introducing a distinct ultrasonic signal at a distinct frequency into the liquid of the storage apparatus and receiving a reflected signal from the liquid-gas interface;a circuit for driving the ultrasonic transducers and receiving reflected signals from the transducers through a single transmission path, the circuit for driving the ultrasonic transducers and for receiving signals from the transducers comprising: (i) a drive circuit operable to drive the transducers collectively with a single drive signal; and (ii) a filter network, wherein the filter network is operable to distinguish the reflected signals from one another for subsequent calculation of liquid level at each of the locations of the transducers; anda processor in communication with the circuit which calculates the liquid level at each of the locations of the ultrasonic transducers based on the reflected signal received from each transducer by the circuit.