| 摘要 |
PURPOSE:To judge the forward and reverse rotations of a rotary gear and to obtain a flowmeter for two directions, by providing two pickups at an angle, which is smaller than 1/2 the angle between projections of the rotary gear of the turbine flowmeter, and comparing the delay time between the detections of the projections. CONSTITUTION:Projections are provided on the rotary gear of a turbine flowmeter at an angle theta2. Two pickups 13 and 14 are provided in the vicinity of the rotary gear. An angle theta1 between the pickups 13 and 14 has a relationship of theta1<1/2theta2. When the rotary gear is rotated in the forward direction (l) shown by an arrow, the detection of the projection by the pickup 14 is delayed by a time t1. After the elapse of time t2, the pickup 13 detects the next projection. The relationship between the times t1 and t2 becomes t1<t2. When the rotary gear is rotated in the reverse direction, the relationship becomes t1>t2. By detecting and comparing the times t1 and t2, the forward and reverse rotations of the rotary gear can be detected. |
