SU1522057A2 - Instrument transducer of pressure difference - Google Patents

Abstract

The invention relates to instrumentation and can be used in the development of pressure difference transducers with membrane elastic sensing elements. The purpose of the invention is to improve the measurement accuracy by reducing the temperature error. On both sides of the base 1, diaphragms 2 and 3 are mounted, interconnected by a stem 4. The movement of the diaphragms is transmitted to the lever 6 of the lever device. The stem is equipped with discs 7 and 8, at the ends of which the grooves are made. Thermo-bimetallic compensators 10 and 11, made in the form of a part of a sphere, are installed in the grooves. Compensators active convex layer facing the membrane. When the ambient temperature changes, the volume of liquid in the cavity of the device changes, for example, as the temperature increases, the volume of liquid increases. At the same time, the compensators 10 and 11, increasing the curvature, move the centers of the membranes 2 and 3 from the hard disks 7 and 8, thereby increasing the volume of compensation cavities 12 and 13, where part of the liquid flows through the holes 14, while the position of the membranes remains unchanged. 2 Il.

Description

1 (61) 506224

(21) 4264258 / 24-10

(22) 06/16/87

(46) 11/15/89. Bhl. P 42

(71) Central Design Bureau Geplopribor

(72) V.I. Chegodaev (53) 531.787.2 (088.8)

(56) USSR Copyright Certificate No. 506224, cl. G 01 L 13/02, 1973. I,

(54) MEASURING DIFFERENCE TRANSFORMER PRESSURE 1TH

(57) The invention relates to instrument making and can be used in the development of pressure difference transducers with membrane elastic sensitive elements w. The purpose of the invention is to improve the accuracy of 1 AND

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measurements by reducing the temperature error. On both sides of the base 1, diaphragms 2 and 3 are mounted, interconnected by a stem 4. The movement of the membranes is transmitted to the lever 6 of the lever device. The stem is equipped with discs 7 and 8, at the ends of which the grooves are made. Thermo-metallic compensators 10 and 11 are installed in the grooves, made in the form of a part of a sphere. Compensators active convex layer facing the membrane. When the ambient temperature changes, the volume of liquid in the cavity of the device changes, for example, as the temperature increases, the volume of sediment increases. At the same time, the compensators 10 and 11, increasing the curvature, move the centers of the membranes 2 and 3 away from the gesture (O

with:

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315220574

discs 7 and 8, thereby magnifying through the holes 14, at the same time finding the volume of compensation cavities, the position of the membranes remains unchanged- 12 and 13, where a part of the liquid flows, 2 sludge.

The invention relates to instrumentation and can be used in the development of differential pressure transducers with membrane elastic sensing elements.

The purpose of the invention is to improve the measurement accuracy by reducing the temperature error.

FIG. 1 shows the device, a general view; in fig. 2 — node I in FIG. one.

The device consists of a base t, two membranes 2 and 3, located on both sides of the base and attached to it along the outer contour, the central parts of the membranes are rigidly interconnected by a stem 4 passing through the hole a of the base 1. The hole 5 of the stem 4 is inserted the end of the lever 6 of the lever device, which transmits the movement of the membranes 2 and 3 to a conversion device (not shown), which controls the output signal. The rod 4 has disks 7 and 8 at its ends, at the ends of which there are circular grooves 9. In the grooves 9, thermo-bimetallic compensators 10 and 11 are installed, made in the shape of a part of a sphere. Compensators active vtuklm layer facing the membrane. The membranes 2 and 3 are rigidly attached to the periphery of the disks 7 and 8, forming compensation: cavities 12 and 13. There are holes 14 in the disks, ensuring the communication of compensation cavities with the cavity between the measuring diaphragms. Measuring membranes. The measuring membranes 2 and 3 and the flanges 15 and 16 form measuring positive and negative chambers into which the measured pressures are fed. The internal cavity, filled with liquid, is closed with a plug 17. The positive and negative chambers with the gasket 18.

The device works as follows.

The larger of the two measured pressures is supplied to the membrane 2 through the opening in the flange 15, and the smaller to the: membrane 3 through the opening in the flange 16. Both. the pressure is converted by the membranes into proportional forces directed towards each other and acting along the common axis of the membranes 2 and 3 and the hard disks 7 and 8. The resulting force through the rod 4 is re-directed to the end of the lever 6, the other end of which intrinsic device, modifies the output signal proportional to the difference

pressures. When the ambient temperature changes, the volume changes; for example, as the temperature increases, the volume of the liquid increases. Simultaneous compensators 10

and 11, increasing the curvature, move the centers of the membranes 2 and 3 from the hard disks 7 and 8, increasing the volume of the compensation cavities 12 and 13, to which part of the liquid flows. .

The invention makes it possible to reduce the error resulting from a change in the volume of a liquid with a change in temperature, i.e. increase the accuracy of the measuring device.

Claims (1)

Invention Formula Differential pressure transmitter for auth. St. P 506224, characterized in that, in order to increase the measurement accuracy by reducing the temperature error, it is equipped with compensators made of a thermopetal as part of a sphere and installed in cavities formed by the central parts of the membranes and the disk w, and the active layer of thermobimetals is placed on the convex side of the compensators and facing the centers of the membranes. fie2