Device for measuring a respired amount of air
First Claim
1. A device for measuring a respired amount of air comprising a respired amount of air-indicating signal generator for detecting an amount of air respired by a body to be measured and generating an electrical signal corresponding to said respired amount of air, an impedance pneumograph for detecting an impedance variation corresponding to said respired amount of air of said body, a reference level setting circuit for receiving an output signal from said impedance pneumograph to set a reference level with respect to said output signal, a memory circuit for receiving, when it is placed in a write-in mode, an output signal from said reference level setting circuit as a writing address signal and storing as information an output signal from said respired amount of air-indicating signal generator corresponding to said output signal from said reference level setting circuit, a peak-to-peak amplitude detector for detecting a maximum amplitude for each cycle of said output signal from said impedance pneumograph, a calibration completion-detecting circuit for detecting that said output signal from said respired amount of air-indicating signal generator has exceeded a specified level, to indicate that a desired calibration signal has been obtained, and an operation mode selecting means for setting, when it has received a calibration completion-indicating output signal from said detecting circuit, said memory circuit to a readout mode and electrically isolating said respired amount of air-indicating signal generator and said reference level setting circuit from said memory circuit and simultaneously coupling said peak-to-peak amplitude detector to said memory circuit, thereby to read out a respired amount of air-indicating information signal stored in said memory circuit by using an output signal from said peak-to-peak amplitude detector as a reading address signal.
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Accused Products
Abstract
There is provided a device for measuring a respired amount of air comprising a hot wire anemometer for converting the variation in the amount of air respired from human lungs into an electrical signal, an integrator circuit for integrating an inhalation phase component of the output signal from the hot wire anemometer, and an impedance pneumograph for generating an output signal corresponding to the variation in the respired amount of air. The output signal from the integrator is stored in a memory in accordance with the output signal from the impedance pneumograph. The information signal stored in the memory is read out from the memory in accordance with an address signal corresponding to the amplitude of the output signal from the impedance pneumograph and is then displayed by a display.
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Citations
20 Claims
- 1. A device for measuring a respired amount of air comprising a respired amount of air-indicating signal generator for detecting an amount of air respired by a body to be measured and generating an electrical signal corresponding to said respired amount of air, an impedance pneumograph for detecting an impedance variation corresponding to said respired amount of air of said body, a reference level setting circuit for receiving an output signal from said impedance pneumograph to set a reference level with respect to said output signal, a memory circuit for receiving, when it is placed in a write-in mode, an output signal from said reference level setting circuit as a writing address signal and storing as information an output signal from said respired amount of air-indicating signal generator corresponding to said output signal from said reference level setting circuit, a peak-to-peak amplitude detector for detecting a maximum amplitude for each cycle of said output signal from said impedance pneumograph, a calibration completion-detecting circuit for detecting that said output signal from said respired amount of air-indicating signal generator has exceeded a specified level, to indicate that a desired calibration signal has been obtained, and an operation mode selecting means for setting, when it has received a calibration completion-indicating output signal from said detecting circuit, said memory circuit to a readout mode and electrically isolating said respired amount of air-indicating signal generator and said reference level setting circuit from said memory circuit and simultaneously coupling said peak-to-peak amplitude detector to said memory circuit, thereby to read out a respired amount of air-indicating information signal stored in said memory circuit by using an output signal from said peak-to-peak amplitude detector as a reading address signal.
Specification