| 摘要 |
<p>A purge type vortex flowmeter capable of accurately measuring a flow rate of fluid over a wide range by reliably detecting the number of vortexes produced. A purge type vortex flowmeter which comprises a vortex generator ( 2 ) mounted in a passage of fluid to be measured in a flow pipe ( 1 ), two conduits ( 4 a, 4 b) having pressure ports ( 3 a, 3 b) in both side surfaces of the vortex generator for communication with the outside thereof and a front conduit ( 4 c) having a pressure port ( 3 c) in the front surface of the vortex generator. Purge fluid from a purge supply source is fed by a purge introducing means through a tube ( 5 ), the conduits ( 4 a, 4 b) and the front conduit ( 4 c) into a flow of fluid to be measured in the flow pipe. Purge streams alternatively fluctuating by the effect of a difference from a fluctuating vortex pressure are discharged from the conduits ( 4 a, 4 b) through their pressure ports ( 3 a, 3 b). The fluctuations of the purge streams are detected by sensors (heat-sensitive elements ( 7 a, 7 b)) mounted in the conduits ( 4 a, 4 b). The purge fluid to be discharged through the pressure port ( 3 c) varies its flow in accordance with the flow of the fluid to be measured in the flow pipe ( 1 ), thereby achieving automatic control of the purge flow to the sensor portion.</p> |
