Apparatus for measuring temperature
First Claim
1. An apparatus for measuring the temperature of an object which is a medium for ultrasonic sound wave propagation, said apparatus comprising:
- pulse generator means for generating first pulse signals continuously at a predetermined frequency;
transmitter means for transmitting ultrasonic sound waves toward said object in synchronized relation with said first pulse signals of said pulse generator means;
receiver means for receiving said ultrasonic sound waves transmitted through said object at a location spaced from said transmitter means by a predetermined distance, said receiver means generating second pulse signals in synchronized relation with the received ultrasonic sound waves, said receiver means including,a transducer for producing transducer signals across output terminals thereof in response to said received ultrasonic sound waves, anda comparator connected to receive said transducer signals across input terminals thereof for converting said signals into said second pulse signals, said comparator being provided with a resistor between the output terminal and one of said input terminals thereof such that said second pulse signals is kept independent of the temperature;
detector means for detecting the phase difference between said first and second pulses to generate third pulse signals having time intervals equal to the detected phase difference; and
measuring means for measuring said time intervals of said third pulses to provide output values indicative of the temperature of said object in proportion to the measured time interval.
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Accused Products
Abstract
An apparatus for measuring the temperature of a medium such as air or the like by the use of a change in the propagation speed of an ultrasonic sound wave depending on the temperature change of the medium. An acoustic transmitter transmits a carrier as an ultrasonic sound wave continuously through the medium to a receiver by exciting an ultrasonic wave vibrator with a series of pulses which constitute the carrier. The received ultrasonic wave when amplified exhibits a series of pulses having a constant signal level irrespective of a change in the amplification factor of the amplifier in the receiver.
43 Citations
6 Claims
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1. An apparatus for measuring the temperature of an object which is a medium for ultrasonic sound wave propagation, said apparatus comprising:
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pulse generator means for generating first pulse signals continuously at a predetermined frequency; transmitter means for transmitting ultrasonic sound waves toward said object in synchronized relation with said first pulse signals of said pulse generator means; receiver means for receiving said ultrasonic sound waves transmitted through said object at a location spaced from said transmitter means by a predetermined distance, said receiver means generating second pulse signals in synchronized relation with the received ultrasonic sound waves, said receiver means including, a transducer for producing transducer signals across output terminals thereof in response to said received ultrasonic sound waves, and a comparator connected to receive said transducer signals across input terminals thereof for converting said signals into said second pulse signals, said comparator being provided with a resistor between the output terminal and one of said input terminals thereof such that said second pulse signals is kept independent of the temperature; detector means for detecting the phase difference between said first and second pulses to generate third pulse signals having time intervals equal to the detected phase difference; and measuring means for measuring said time intervals of said third pulses to provide output values indicative of the temperature of said object in proportion to the measured time interval. - View Dependent Claims (2, 3)
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4. An apparatus for measuring the temperature of an object which is a medium for ultrasonic sound wave, said apparatus comprising:
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pulse generator means for generating a train of first pulse signals at a fixed frequency; transmitter means for transmitting ultrasonic sound waves toward said object in timed relation with said first pulse signals of said pulse generator means; receiver means for receiving said ultrasonic sound waves transmitted through said object at a location spaced from said transmitter means, said receiver means generating a train of second pulse signals in timed relation with the received ultrasonic sound waves, said receiver means includes; a transducer for producing transducer signals across output terminals thereof in response to said received ultrasonic sound waves; and a comparator connected to receive said transducer signals across input terminals thereof for converting said signals into said second pulse signals, said comparator being provided with a resistor between the output terminal and one of said input terminals thereof such that said second pulse signals is kept independent of the temperature; logic means for subjecting said first pulse signals and said second pulse signals to a predetermined logic operation to generate a train of third pulse signals having time intervals corresponding to the phase difference between said first pulse signals and said second pulse signals generated at the same instant in time; and utilization means for utilizing said third pulse signals to measure the temperature of said object.
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5. An apparatus for measuring the temperature of an object which is a medium for ultrasonic sound wave, said apparatus comprising:
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pulse generator means for generating a train of first pulse signals at a fixed frequency; transmitter means for transmitting ultrasonic sound waves toward said object in timed relation with said first pulse signals of said pulse generator means; receiver means for receiving said ultrasonic sound waves transmitted through said object at a location spaced from said transmitter means, said receiver means generating a train of second pulse signals in timed relation with the received ultrasonic sound waves; logic means for subjecting said first pulse signals and said second pulse signals to a predetermined logic operation to generate a train of third pulse signals having time intervals corresponding to the phase difference between said first pulse signals and said second pulse signals generated at the same instant in time; and utilization means for utilizing said third pulse signals to measure the temperature of said object, said utilization means includes; oscillator means for generating clock signals; another logic means for subjecting said third pulse signals and said clock signals to another predetermined logic operation; and counter means for counting said clock signals passed through said another logic means to provide output values indicative of the temperature of said object. - View Dependent Claims (6)
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Specification