SU1267182A1 - Pressure difference frequency pickup - Google Patents

Abstract

The invention is adapted to measurement technology and permits an increase in the sensitivity of the sensor at high static pressures. On the inner surface of the housing, on both sides of the membrane 2, grooves 15 are formed, forming windows that eliminate the influence of deformation of the housing with pins 12 when exposed to static; pressure on the caps 13. The grooves 15 are separated from the cavities 10, 11 by a sealing element made in the form of a thin-walled elastic conical protrusion 14, preventing bending deformation of the housing 1. Under the action of the pressure difference in the cavities 10 and 11, the membrane 2 is deformed in section 7 and transmits force on the working rack 4 of the sensing element 3. The change in the frequency of the sensing element characterizes the measured change in pressure difference. 3 il. S O)

Description

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The invention relates to a measurement technique and can be used in pressure differential measurement systems at high static pressures.

The aim of the invention is to increase the sensitivity of the frequency sensor for measuring pressure differences at high static pressures.

Figure 1 shows a schematic of the sensor, a general view; figure 2 is a view of And figure 1; on fig.Z - section bb in figure 1.

The cylindrical body 1 is made with a membrane 2 and a vibrating rod frequency sensitive element 3 with a working stand 4 and a stand 5 located in the plane of the membrane 2, and the working stand 4 is open on the thin-walled part 6 of case 1.

The membrane 2 has a thin-walled 7, a thickened 8 sections and a transfer lever 9, located opposite the working rack 4.

Covers 13 are installed in the cavity of the Yun 11 body with the help of pins 12 (three in each cavity). At the end of each cover, the lining | Tei is sealed with it. 10 and P on the inner surface of the housing 1, the cuff 14 is a sealing element in the form of an elastic conical protrusion. In each cavity 10 and 11, a groove 15 is formed in the body of the housing 1 parallel to the plane of the membrane 2, forming a window 16 in the thin-walled part 6 of the housing 1 near the working stand 4 of the sensing element 3.

The caps 13 are mounted so that the edge of the cuff 14 is located between the membrane 2 and the groove 15. To connect the sensor to the object of measurement, body 17 has fittings 17 and 18 connected to cavities 10 and 11 bounded by cuffs 14.

The device works as follows.

When a pressure difference in cavities 10 and 11 is applied through nozzles 17 and 18, the membrane is deformed in the thin-walled section 7 and transmits the force through section 8, the transfer lever 9 and the thin-walled parts 6 of the housing 1 to the working rack 4 of the frequency sensitive element 3.

671822

At the same time, the frequency of the latter varies in a certain functional dependence on the pressure difference. The frequency change measured by the secondary instrumentation (not shown) is a measure of the pressure differential. Since the housing 1, the membrane 2, the supports 4 and 5, and the vibro-rod sensitive element 3 are made in one piece, the sensor does not have friction links and is highly accurate.

Both racks 4 and 5 of the sensing element 3 are located in the plane

15 of the membrane 2, therefore, the sensor is compensated for by high static pressures on its readings.

The location of the cuff 14 in the immediate vicinity of the membrane 2 prevents bending deformations of the housing 1 from static pressure in the cavities 10 and 11. Due to the presence of grooves 15 that form thin-walled annular walls in the body of the housing 1, the influence of the deformation of the housing 1 with the pins 12 is eliminated from the effects of static pressures on the covers 13.

The presence of windows 16 around working stand 4 allows a substantial increase in the sensitivity of the sensor, which helps reduce the influence of high static pressures.

Thus, the frequency sensor has an increased sensitivity when measuring high static pressures due to constructive

40 weakening of the body in the area of the membrane

Claims (1)

Invention Formula 45 The frequency differential pressure sensor, containing a cylindrical housing with constants, divided by a membrane into two cavities, sealed with sealing elements along 50 of the inner surface of the housing, a converter with a working stand, located outside on the thin-walled part of the housing in the plane of the membrane, characterized in that 55 in order to increase sensitivity, grooves are made on the inner surface of the housing on both sides of the membrane, forming two windows in the tone3 of the bone part of the housing, and each sealing element is designed as a thin-walled elastic conical protrusion along with a lid on its / end part and separates cavity from the groove.