| 摘要 |
<p>PURPOSE:To constitute the measuring instrument so as to be scarcely influenced by an external factor such as an ambient temperature, humidity, etc. CONSTITUTION:In the pressure measuring instrument for counting by a counter the number of pulses of an oscillating circuit whose frequency is varied in accordance with applied pressure P, a count value N00 at the time of opening the air at the time of calibration, and a span value N280 are stored in a memory in advance, and they are read out at the time of measurement (ST21), and also, opened to the air (ST22), pressure at the time is obtained as a count value NO (ST23, ST24), and a difference DELTAN of NS and N00, and Ns'=Ns+k1XDELTAN are calculated (ST25). By using this corrected Ns', pressure Px is measured by Px=(N0-Nx)XN280/Ns'.</p> |
