Bourdon tube pressure transducer - has local needle indicator and strain gauges for remote indication

摘要

The pressure transducer has a C-shaped Bourdon tube (1) receiving the measurement pressure-medium at one end, the other of which is deflected according to the pressure. Strain gauges (DMS1 to DMS2) produce electrical signals dependent on the tube deflection. Increased sensitivity is achieved compared to similar devices. Both remote and local indication are incorporated. The dynamic measurement limitations due to friction in similar arrangements are overcome as are the linearity errors caused by the use of potentiometers. Four strain gauges connected in a full bridge circuit are mounted tangentially in pairs on the inner (2) and outer (3) curved surfaces of the tube. A detachable conventional pointer indicator (12,13,16,17) is connected to the free end of the tube. Each arm of the bridge circuit contains one strain gauge from the outer, and one from the inner curved surface.