PHASE DIFFERENCE DETECTOR

摘要

PURPOSE:To elevate the stability under a noise of the same phase by a method wherein first and second signals are compared with first and second thresholds while the resulting output is integrated corresponding to a time difference between the rising and falling thereof to make a first threshold. CONSTITUTION:In a phase difference detector 5 for output signals e11 and e12 of strain detecting elements 3 and 4 in a tube 2 with a fluid flowing through a mass flowmeter 1, the signals e11 and e12 are inputted into comparison means 8 and 9 with respect to respective thresholds through amplifiers 6 and 7 and a pulse waveform with the pulse width corresponding to the time difference in the rising between the output e15 and e16 and the rising order thereof to the polarity thereof is generated from a time difference measuring means 10. In addition, the output e17 is integrated with an integration circuit 11 to use the output eOUT thereof as threshold voltage of the means 8 while the threshold value of the means 9 is set at a common level.