Strain tube
The drum is also called the strain. Its elastic sensitive element for thin-wall cylinder closed at one end, the other end with a flange connected to the system under test. On the wall with 2 or 4 pieces strain gauge, half of them on the solid part as temperature compensation, the other half as a strain gauge measurement. When there is no pressure on four slices of full bridge circuit of strain gauge balance; When the pressure ACTS on the inner chamber, cylinder form "drum-shaped", make a bridge out of balance, the output voltage into a certain relationship with the pressure. The sensors can also be used to convert measured pressure piston can't passed to the strain on the tube, or through the vertical chain in the shape of diaphragm pressure being measured. Strain tube type pressure sensor of simple structure, easy fabrication, high applicability, the rockets, artillery and artillery dynamic pressure measurement has a wide range of applications.
diaphragm
Its elastic sensitive element for around a circular flat diaphragm metal. Diaphragm pressure deformation, radial and tangential strain reaches the center was the maximum, and strain at the upper end of the negative radial edge tangential strain is zero. So often stick two strain gauge on the positive and negative maximum strain, and into the adjacent bridge arm half bridge circuit for high sensitivity and temperature compensation. Using round foil strain gauge (see the resistance strain gage) can make the most of the strain of the diaphragm effect. This kind of sensor has obvious nonlinear. Diaphragm type pressure sensor in the latest product is elastic sensitive element and the function of the strain gauge set on monocrystalline silicon diaphragm, which USES integrated circuit technology made on monocrystalline silicon diaphragm diffusion resistance, and adopts the perimeter fixed structure made of solid pressure sensor (see piezoresistive sensor).
Strain beam
When measuring pressure, can use a fixed beam or equal strength beam structure. One way is to use the diaphragm pressure conversion can travel through the dowel bar is passed to the strain beam. In figure 3 both ends fixed beam maximum strain at the ends of the beam and the midpoint, strain gauge is posted in these areas. The structure and other forms, such as cantilever beam and a diaphragm or corrugated pipe can be used.
combined
In combined-type strain pressure sensor, elastic sensitive components can be divided into sensitive element and elastic strain components. Sensitive element transformation do pass the pressure on strain is the most sensitive part of the elastic strain component, and strain gauge is attached to the maximum strain elastic strain components. In fact more complex strain tube and strain beam belong to this type. Sensitive element has a diaphragm, bellows, bellows, bourdon tube, such as elastic strain components cantilever beam, beam and fixed Π girder, ring beam, thin wall tube, etc. Can be combined into a variety of types according to the different between them. Strain type pressure sensor is mainly used to measure the dynamic or static pressure flow medium, for example, the power pipeline equipment import and export of gas or liquid pressure, the internal combustion engine pipeline pressure and so on.
