PURPOSE: To permit a pressure sensor to perform a wide range of pressure measurement and to prevent the breakage of a quartz oscillator therein by applying pressure to a pressure cell through a pressure mechanism in which a pair of magnets are arranged so that their same polarties are opposed to each other in order to apply pressure to the quartz oscillator provided in it.
CONSTITUTION: A cylinder 1 is provided with a magnet 3 on the bottom. A cylindrical body 4 is provided with a magnet 5 so that its polarity is opposed to that of the magnet 3, and is inserted into the cylinder 1. A pressure cell 7 is provided between the magnets 3 and 5 through buffer springs 6. A quartz oscillator 8 is provided in the space inside the pressure cell 7. The output of the oscillator 8 is connected to an amplifier 9, which forms an oscillation circuit together with the oscillator 8 and oscillates at a frequency corresponding to the change in the pressure to be measured. In the constitution, the magnets 3 and 5 repulse each other with a force inversely proportional to the square of the interpole distance, and the pressure applied to the oscillator 8 is proportional to the interpole distance. Consequently, a wide range of pressure measurement is possible without a pressure mechanism utilizing a lever. Moreover, since an air pressure is employed for applying pressure on the oscillator 8, it is prevented from breaking.
ISHIWATARI JIYUNICHI
YOSHIOKA NOBUYUKI
MEIDEN TSUUSHIN KOGYO KK