PHYSICAL QUANTITY SENSOR

摘要

A physical quantity sensor 100 includes: first and second oscillators 1, 2 that are supported by a support member 9; first and second detection devices 4, 5 for detecting the oscillations of the first and second oscillators respectively; a sensor element 6 that is provided on the first or second oscillator and has characteristics capable of adsorbing and/or desorbing a measurement object; an elastic device 7 for coupling the first and second oscillators to each other; and a calculation device 8 for determining a frequency at which the vibrating device 3 vibrates the first oscillator. The calculation device determines the frequency so as to maximize the amplitude of the second oscillator, and calculates the mass or concentration of the measurement object on the basis of the ratio of the amplitude of the second oscillator to the amplitude of the first oscillator when the vibrating device vibrates the first oscillator.

主权项

1. A physical quantity sensor, comprising:
a support member; a first oscillator supported by the support member; a vibrating device adapted to vibrate the first oscillator at a prescribed frequency; a first detection device adapted to detect oscillations of the first oscillator; a second oscillator supported by the support member; a second detection device adapted to detect oscillations of the second oscillator; a sensor element that is provided on the first oscillator or the second oscillator and has characteristics capable of adsorbing and/or desorbing a measurement object; an elastic device adapted to couple the first oscillator and the second oscillator to each other; and a calculation device adapted to determine the prescribed frequency and to calculate a mass or concentration of the measurement object, wherein the calculation device is adapted to determine the prescribed frequency so as to maximize an amplitude UO2 of the second oscillator detected by the second detection device, and is adapted to calculate the mass or concentration of the measurement object based on a ratio UO2/UO1 of the amplitude UO2 of the second oscillator detected by the second detection device to an amplitude UO1 of the first oscillator detected by the first detection device when the vibrating device vibrates the first oscillator at the determined frequency.