초록 ▼

An empty container detector comprises a photoelectric transducer associated with the fluid container which generates a variable control signal to alternately indicate whether the light path of the photoelectric transducer is being refracted by a fluid. A second photoelectric transducer is associated

An empty container detector comprises a photoelectric transducer associated with the fluid container which generates a variable control signal to alternately indicate whether the light path of the photoelectric transducer is being refracted by a fluid. A second photoelectric transducer is associated with the fluid container above the fluid level in the container to establish a reference signal corresponding to the condition wherein the light path is not refracted or attenuated by the presence of a fluid. Electrical means are provided to connect the first photoelectric transducer to the second photoelectric transducer to linearize and normalize the reference signal with the control signal. A comparator is associated with the photoelectronic transducers and connected to an alarm which indicates when the control signal is substantially equivalent to the reference signal and thus indicating the lowering of the fluid level below the light path of the first photoelectric transducer.

대표청구항 ▼

A fluid level detector for use with a transparent fluid container which comprises; a photoelectric transducer associated with said container having its light path aimed through said container for operating in a first state when said light path is refracted by a fluid in said container and operating

A fluid level detector for use with a transparent fluid container which comprises; a photoelectric transducer associated with said container having its light path aimed through said container for operating in a first state when said light path is refracted by a fluid in said container and operating in a second state when said light path is unrefracted by a fluid; means associated with said container to establish a normalized input to said photoelectric transducer corresponding to no fluid in said container; and an alarm associated with said transducer to indicate an empty container when said second state is a calibrated equivalent to a no fluid condition as established by said normalized input.