HF welding machine for plastics - regulates and measures pressure applied to work by meter whose leads enter earthed metal casings through tightly fitting insulation

摘要

A high frequency welding machine for plastics has an hydraulic pressure system to press the work, an instrument to measure the applied pressure, and an enclosed regulator with data processing device, the pressure meter being housed inside a metal sensor enclosure. The meter leads are passed into the sensor enclosure through h/f filters encapsulated in metal casings which form one closed metal coupling with the sensor enclosure; this is earthed, and the leads into the filter casing are tightly surrounded in insulation. ADVANTAGE - The layout guards the control circuit systm from electromagnetic interference.