Displacement Sensors in Hydraulic cylinders


Thread Starter

R. S. Newton

I want to be able to accurately record the extension of a hydraulic clinder. It is not possible to use standard linear transducer. I was thinking about putting an ultrasonic transmitter/receiver in the "full" end of the cylider and "bouncing" the signal off the full piston. Has anyone done anything like this before? Will it work under high pressure 250+ bar, in hydraulic oil?


Mike Schoonmaker

Hydroline cylinders (recently bought by Eaton) were availabe fro a while, but have been taken off the market. It exhibited many problems, most importantly instability due to any entrained particulate in the cylinder, including air, dirt, water. It was also fluid temperature sensitive, which is very difficult to control.

Most folks today use magnetostrictive sensors, available from Balluff, MTS Systems (Temposonics), Patriot Sensors, or TR Encoders.