Impeller type flowmeter for household appliance has optical barrier arrangement for sensing movement of impeller that is much more cost-effective than existing magnetic sensor arrangements

摘要

Flowmeter comprises an impeller (3) within a housing and an optical radiation transmitter (9) and receiver (10). The radiation path or optical barrier between transmitter and receiver passes through the impeller housing. Typically a low-cost infrared LED can be used as a light source with a corresponding detector.