Viscosity compensated flow meter VKM – KOBOLD
The KOBOLD flowmeters and switches model VKM have a spring-loaded float, which slides within a cylindrical measuring tube and has an integral orifice which is believed to be unique. This and other design features mean that it has for the first time become possible to create a flowmeter and switch which fully compensates for viscosity and to a large extent for density even with very low flows.
The float of these patented devices contains a permanent magnet which actuates a potential free bistable reed contact mounted outside the flow thus ensuring hermetic separation between the medium and the electrical contact system. The contact is embedded within a height-adjustable plastic housing to prevent damage to the contacts by mechanical action or aggressive atmospheres.