PURPOSE: To simultaneously find a digital pressure display and a display indicating a pressure trend, by a method wherein a data on a trend of a pressure is found from a pressure value indicated by a vacuum gauge, and the data is displayed by means of a latter symbol and the like through computation.
CONSTITUTION: If a digital pressure value Pd is inputted at a clock T1, it is held in a computing circuit 14 at a time T1+ΔT. A substratcting circuit 12 performs a substraction between a pressure value at a clock T2 inputted at a current time and a pressure value at the time T1+ΔT held in the computing circuit 14 to generate a difference output. Specified thresholds VSH1 (plus) and VSH2 (minus) are previously stored in comparing circuits 15 and 16, respectively, the comparing circuits input said difference output, and either of them is outputted depending on whether it is higher or lower than the threshold respectively owned by them.
| JPS60177235 | CALIBRATING DEVICE OF VACUUM GAUGE |
| JP4437336 | Capacitive vacuum sensor |
TAMURA YOSHIICHI
OOSAKO SHINJI
ABE ATSUSHI
| JPS5429821U | 1979-02-27 | |||
| JPS52123254A | 1977-10-17 |