SU911183A1 - Device for testing pressure pickups - Google Patents

Description

The invention relates to instrumentation, in particular to devices for testing pressure sensors.

Gas pulsators are known for producing pressure pulsations in a gas medium, consisting of a housing in which disks having a system of special windows are located. Some disks are fixed on the casing motionlessly, others are driven by an electric motor and periodically block the windows on a fixed disk 10, as a result of which fluctuations in air flow and pressure in the pulsator's air duct (1].

However, these pulsators have a small and unstable value of static pressure, against which pressure pulsation occurs, and a large gas flow rate.

The closest in technical essence — jg essence and the achieved technical effect to the proposed one is a device for testing pressure sensors containing a working cylinder with a sealed piston with a rod and an electric motor [2]. <

However, the known device does not make it possible to obtain a pressure that can be changed according to a sinusoidal law with high values of statistical pressure.

The purpose of the invention is to increase the accuracy of calibration at high pressures.

This goal is achieved by the fact that in the device for testing pressure sensors containing a working cylinder, with a sealed piston with a rod and an electric motor, a sealed housing with guides located in it and a movable carriage on them, inside which an unbalance is installed in the bearings, connected by a flexible connection with an electric motor, while the carriage is rigidly connected to the piston rod, and the working cylinder is hermetically connected to the housing.

The drawing shows the design of the device.

911183 4

The device consists of an unbalance 1, a piston 2, a working chamber 3 pressure pulsation? cover 4, guides 5, carriage 6, housing 7, flexible coupling 8, electric motor 9, pressure outputs 10, 5 of the lower cover 11, rod 12, fitting 13 for supplying static pressure and fitting 14 for the pressure gauge.

The device operates as follows. . *

Through the hermetic terminals 10, a direct current voltage is supplied to the electric motor 9. The rotation of the rotor of the electric motor through a flexible coupling is transmitted to the unbalance 1, the axis of which is mounted on the bearings in the carriage 6, which, under the action of the centrifugal force developed by the unbalance 1 during its rotation, makes a reciprocating movement along the axis of the chamber 3 of pressure pulsation along the guides 5 installed in internal cavity of the housing 7.

The movement of the carriage is transmitted through the rod 12 to the piston 2, which also makes a reciprocating movement in the chamber 3 of the pressure pulsation variable pressure acting on the tested transducer installed in the threaded hole of this chamber. In this case, the alternating pressure is created against the background of the static pressure set through the nozzle 13 from the pressure source. The value of static pressure is controlled by a suitable device connected to the fitting 14.

The proposed design allows, with an almost constant value of static pressure, to obtain an alternating sinusoidal pressure. Moreover, the value of the set static pressure is limited only by the strength characteristics of the pulsator design.

Claims (2)

... 1 .... The invention relates to instrumentation, in particular to devices for testing pressure sensors. Gas pulsators are known for P6. Pressure pulsations in a gaseous medium, consisting of a casing in which the disks are arranged, having a system of special windows. Some discs are fixed on the casing fixedly, others are rotated by an electric motor and periodically overlap the windows on the fixed disc, as a result of which they reward. fluctuations in air flow and pressure in the air path of the pulsator tl However, these pulsators have a small and unstable static pressure, against the background of which pressure pulsation occurs, and a large gas flow. The closest in technical essence and achievable technical effect to the proposed is a device for a test pressure sensors, which contains a working cylinder with a sealed piston with a rod and an electric motor C2 3. However, the known device does not allow obtaining pressure, which is sinusoidally modulated at high values of statistical pressure. The purpose of the invention is to improve the accuracy of calibration at high pressures. The goal is achieved by the fact that a sealed housing with guides located in it and a movable carriage on them are inserted into the device for testing pressure sensors containing a working cylinder with a piston and a movable carriage, inside which there is an imbalance connected to with an electric motor, the carriage is rigidly connected to the piston rod, and the working cylinder is tightly connected to the housing. The drawing shows the constructive device. 0 The device consists of unbalance 1, piston 2, pressure chamber 3, pressure pulsations of cover 4, guides 5, carriage 6, housing 7, flexible coupling 8, electric motor 9, thermal outlets 1O, bottom cover 11, stem 12, fitting 13 for inlet static pressure and igguzer 14 for a pressure gauge. The device works as follows. Through the sealed leads 10 to the electric motor 9, a DC voltage is applied. The rotor of the electric motor is transmitted through a flexible coupling to unbalance 1, whose axis is mounted in bearings in the carriage 6, which, under the action of centrifugal force developed by unbalance 1, rotates, reciprocates along the axis of the pressure pulsation chamber 3 along guides 5, mounted in the inner cavity of the housing casing 7. The movement of the carriage is transmitted through the rod 12 to the piston 2, which, also reciprocating, creates a variable pressure in the pressure pulsation chamber 3, acting the test transducer to be tested,: installed in the threaded hole of this chamber. In this case, the alternating pressure is created against the background of the static pressure, set via fitting 13 from the pressure source. The magnitude of the static pressure is controlled by an appropriate device attached to fitting 14. 34 The proposed design allows, at a practically constant static pressure, to obtain a variable pressure of sinusoidal shape. Moreover, the value of the specified static pressure is limited only by the strength characteristics of the pulsator design. Formula from acquired and a device for testing pressure sensors, containing a working cylinder with a sealed piston with a rod and an electric motor, characterized in that, in order to improve the accuracy of calibration at high pressures, a sealed housing with guides and a movable carriage located in it is introduced into it on them, inside which the imbalance is installed in the bearings, connected by a flexible coupling with an electric motor, while the carriage is rigidly connected to the piston rod, and the working cylinder is tightly connected to the housing. Sources of information taken into account during the examination 1. USSR author's certificate No. 291117, cl. G01L4 27/00, 1971. 2. USSR author's certificate number 477327, cl. Gi01, 27/00, 1972 (prototype). 55 f