SU1165136A1 - Pressure transducer - Google Patents

Abstract

PRESSURE SENSOR Containing a cylindrical support element placed in a housing with supply channels, on which two thin-walled cylinders with strain gauges are installed, are included in a measuring bridge, characterized in that, in order to improve the accuracy of measurements in a wide temperature range, each strain gauge is made in the form of two combined single-phase windings from a wire to glass insulation, wound on the middle part of a thin-walled cylinder and included in two opposite shoulders of the bridge, while housing is sealed, and the width of two superposed odnor pa windings must not exceed one third of the length of thin walled cylinder ..

Description

11 The invention relates to the field of measurement technology, namely to pressure transducers into an electrical signal. The aim of the invention is to improve the measurement accuracy over a wide range of temperatures. The drawing shows the pressure sensor design, a slit. The pressure sensor contains sensitive elements 1 in the form of thin-walled cylinders, welded with their edges to the tubular support element 2 above the annular grooves 3 with through radial channels 4, which communicate the annular grooves 3 with the channel 5 of the support element 2. In the middle part of the through channel 5 solid partition 6, hermetically separating the inner cavity of the tubular support element 2 1 and two symmetrical halves. The shape and depth of the annular ducts 3, the number and diameter of their through radial channels 4 do not significantly affect the pressure sensor readings, if ideality is observed and simulated on both sides of the partition 6. To the outer surface of the reference zl element 2 with its own The cylindrical housing 7 coaxially enclosing the supporting element is attached to the edges to form a sealed volume 8. The volume 8 can be filled with gas, liquid, or gelatinous medium under atmospheric or other predetermined pressure, which is the same Exposure to both sensor elements 1. To convert the deformation of the sensing element 1 into an electrical signal, thin-walled cylinders wound windings 9 from a strain-resistant microwire in glass insulation: two single-core spatially aligned windings on each thin-walled cylinder, forming two equal opposite arms of the measuring bridge. The windings 9 are wound on top of the sensing element 1, are in volume 8 and are not in contact with the measured medium, which may be aggressive. The spatial combination of the two windings maximally ensures the identity of the effect on them of 6 measured pressure and external conditions. And since the width of the windings from the microwire to the glass insulation does not exceed 30% of the length of the sensing element and is made in the middle part of this element, the readings are linear, since the sensing element in such a narrow area under the action of pressure operates in a linear mode. The windings forming the arms of the measuring bridge with the measuring circuit are connected through the current-supplying water 10, formed in the form of metal half-rings, electrically isolated from the base and from each other. The operation of the pressure sensor can proceed in three modes. In the overpressure measurement mode, when the measured medium is fed from one end of the sensor into the passage channel 5 and through the radial channels 4 it acts on the sensitive element I, which in turn, deformed, acts on the windings 9 of the tensor-resistant microcontrol deformation (local movements) of the sensing element 1 into an electrical signal. At the same time, at the other end of the sensor, the passage channel 5 is open and, through the radial channel, the sensing element 1 is subjected to environmental pressure. In addition, for both sensing elements 1, there is a pressure effect in the volume formed by the surface of the support element 2 and the housing 7. (p -Pl-Cp At the same time, P i - O I - t - P2 is the measured pressure; pressure under the housing 7 , - ambient pressure, - measured medium pressure, Р Р - Р - Р At Р, atm from atm lgr tf - T l where Р а is atmospheric pressure. In the absolute pressure measurement mode, when the measured medium is also supplied From one end of the pressure sensor to the passageway 5, and from the other end, air is pumped out of the passageway 5 and The tucker is sealed with a plug. The mechanism of pressure acting on the sensing elements 1 and the windings 9 is transformed 311165136 /

The pressure bodies in the electric signal by the campus 6, the measured difference is the same. When this is always equal to

pp - p

h 2. -.

RIED, (Ra RO Ro) 5 where E and P - The pressure of one and the other

and at Р, 0} Р „,; and P., i.e. has a design that measures the absolute pressure measurement. „„ Pressure from 0.5 to 200 MPa

In the mode of measuring the difference in pressure, the Design allows the creation of a pressure (pressure differential), when the pressure of the pressure class. Accuracy (0.1% of two compared media is 0.25%) for applying them to various channels 5 in the passageway, kazad from their own industrial zones in the pressure sensor system end. Thanks to the automatic control, regulation and symmetry of the two and. control of technological cavities of the sensor, separated by reprocesses.

measured medium.

Claims (1)

PRESSURE SENSOR containing a cylindrical supporting element located in the housing with supply channels, on which two thin-walled cylinders with strain gauges are installed, included in the measuring bridge, characterized in that, in order to increase the accuracy of measurements in a wide temperature range, each strain gauge is made in it in the form of two combined single-row windings from wire to glass insulation, wound on the middle part of a thin-walled cylinder and included in two opposite shoulders of the bridge, while yc made airtight, and the width of two superposed § odnoryadovyh windings does not exceed one-L · --third of the length of thin walled cylinder. W 6 1 Irzv S Z 7 7 7.7 2/2 2 7 2 2 'Z'Z Z- Z 2777U / / / □ e SP