SU953478A1 - Device for graduation of air speed manometric pickups - Google Patents

Description

(DEVICE FOR GRANNING MONOMETRIC AIR SPEED SENSORS

one.

The invention relates to an instrument structure, in particular for the calibration of gauge sensors when measuring small airspeeds of vehicles or the density of a gaseous medium.

A device for graduation is known. gauge sensors for measuring low vehicle speed, containing pressure receivers, Qi neither (one or two), pressure sensors (one or two) with acoustic filters, carrier frequency generator, power supply battery, amplifier, contactless current collector, demodulators,, 5 filters, pointers and the vehicle itself l.

However, this device lacks the accuracy of setting and controlling the measured speed, as the graduation of the instrument is carried out in formation with a car going on the ground on an inaccurate instrument such as a car speedometer.

The closest to the proposed invention according to the technical .t1, and the achieved result is a device for dynamically calibrating pressure sensors containing a means of setting the pressure in the form of a stand consisting of two bellows, a cam mechanism and a rotating shaft drive connected to the return mechanism forward movement 2.

The disadvantage of this device is that it does not have the ability to transfer the signal from the rotating parts of the device to the fixed ones with the required accuracy, therefore, it is not possible to calibrate pressure sensors located on the rotating elements of the vehicle together with a piece of equipment located on the fixed elements (in the cab ).

Claims (1)

The purpose of the invention is to improve the accuracy of determining the calibration characteristics of gauge sensors and simplify the process of graduation. The goal is achieved by the fact that a device for calibrating air speed manometric sensors, including two bellows connected to a cam mechanism with an actuator, wherein the cavity of each bellows is connected to a pressure sensor, an acoustic filter, and a control pressure sensor is inserted a contactless current collector, containing a rotating transformer with stop and rotor windings, mounted on a rotating drive shaft, a summation unit and a demodulator with a filter, while the outputs of the sensors, pressure They are connected to the stator winding of a rotating transformer via a summation unit, and the rotor winding is connected to the input of a demodulator, the output of which is connected to the input of the filter. The drawing shows a schematic diagram of the device. The device consists of two bellows 1, a drive with a rotating double-sided output shaft 2, a mechanism 3 for the reciprocating movement, a control differential pressure sensor 4, a matching device 5, a recorder 6, two differential pressure gauge pressure sensors 7 with acoustic filters 8, an adder 9, demodulators 1 of active filters 11 and a contactless current collector 12. The device allows the generation of pneumatic pressure signals proportional to the measured airflow rate. The variable speed drive 2 sets the required rotational speed of the double-sided output shaft, which is connected to the reciprocating mechanism 3 on one side and the contactless current collector 12 on the other side. Pressure pulsations are set by compressing and expanding the closed volumes of two bellows 1. The pressure in the bellows is harmonically synchronized with the speed of rotation of the output shaft. The phase of air vibrations in the bellows is shifted relative to each other by 180. The parameters of pulsations are measured by the control differential sensor k and the electrical output signal is fed through matching device 5 to recorder 6. Measurement of pressure, proportional to the measured airspeed, is carried out using two manometric differential pressure sensors 7 with acoustic filters 8, zen | x with an adder 9, a contactless current collector 12, demodulators 10 and active filters 11. The contactless current collector constructively comprises a rotating transformer having Tator and rotor windings, which are shown in the diagram. The signal from the pressure sensors goes through the summation unit to the stator, and from the rotor of the rotating transformer to the rotor of the sine-cosine transformer. This permits all tests to be carried out in a mode that simulates the actual conditions of operation of gauge sensors. In addition, a rotating transformer serves to transmit the velocity vector signal to the cab when the equipment is mounted on the vehicle. The active low-pass filters 11 highlight and amplify the electrical signal, defined by the expression Urvi 2, where and is the current value of the electrical signal, the maximum value of the amplitude of the output signal of the gauge sensors; pj is the slip angle. The use of the proposed device allows an increase in the measurement accuracy, since it is possible to calibrate gauge sensors under laboratory conditions. Apparatus of the Invention A device for calibrating air speed gauge sensors, comprising two bellows coupled to an actuator cam mechanism, wherein the cavity of each bellows is connected to a pressure sensor, an acoustic filter, and a control pressure sensor, characterized in that increase the accuracy of calibration, a contactless current collector containing a rotating transformer with a stator and a rotor is introduced into it