Patent · US Expired

Empty container detector with drop sensor

US4703314A · kind A · utility

125Cited by
8References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 4, 1986
Grant dateOct 27, 1987
Priority date
Expiry dateDec 4, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01F23/2921
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An empty container detector for use with a drip chamber 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 a fluid container above the fluid level in the container to establish a reference signal which is modulated by drops falling into the container and which has a component 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. Another comparator is associated with the photoelectric transducers to count modulations in the refer…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.