Torsion spring flow meter and flow switch for flow rates up to 1900 l/min

Patented flow meter and flow switch using a paddle mounted on a flat torsion spring that acts both as support and as spring element, so that the instrument operates virtually without wear. It covers water flow rates from 5…30 l/min up to 850…1900 l/min, with a brass or stainless steel body and PN 40 pressure rating.

Features

• Measuring ranges from 5…30 l/min to 850…1900 l/min (water)
• Connections G ⅜ … G 3 and ⅜ … 3" NPT
• Materials: brass, stainless steel
• Pressure rating PN 40
• Maximum temperature 80 °C
• Accuracy ±3 % of full scale
• Available with compact electronics or digital display

Operating principle

The paddle consists of a flat disc and a lever arm. The flow moves the disc in its own direction and the arm rotates against the flat spring; this angular movement is transmitted by a magnet, without contact and through the housing wall, to a Hall-effect sensor, with no leakage points. The different measuring ranges are obtained by varying the arm geometry, the diameter and shape of the disc and the spring dimensions; calibration nozzles can be fitted to adapt the range further. The sensor signal is processed by various electronics for flow indication and monitoring.