SU651233A1 - Rotary viscosimeter - Google Patents

Description

one

The invention relates to a device for measuring the viscosity of liquid media.

A rotational viscometer for liquids, a housing with a gearbox, a cup containing a controlled fluid, and an intermediate-drive electric motor are known, which allow to regulate the speed of the output shaft of the gearbox l.

The rotor of the viscometer is located at the end of the output shaft of the gearbox.

The known rotational viscometer containing coaxial cylinders, one of which is connected to a driving motor, and the second to a device for measuring the moment, performed in a two-stage gyro, the casing of which is connected to the measuring cylinder, and the input axis of the measuring cylinder is aligned with the axis of the measuring cylinder, and the output axis of the gyroscope is equipped with an angle sensor, the rotor of which is electrically connected

is connected through an amplifier with a compensating auto switch, mechanically connected to the measuring cell shaft {2J.

The known device does not allow a sufficient range of measurements to be extended.

The purpose of the present invention is to improve the accuracy of measurements in a wide range of viscosity changes.

To do this, the device additionally introduces a stabilizer of the angular motion speed of the pyrocamera, consisting of a phoscopic angular velocity sensor, a reference signal amplifier, an electric motor connected via a rotary-case gearbox, and a reference voltage generator connected to the second input of the amplifier, the winding motor control is connected to the output of the amplifier.

FIG. 1 given kinalapgic scheme of the proposed viscometer;

in fig. 2 and 3 are block diagrams of a viscosity meter;

The gyro motor 2 is installed in the gyrocamera 1, the main axis of which is perpendicular to the longitudinal axis of the 3 gyrocameras 1. The gyroscale chamber 1 with the aid of paphs and bearings is installed in the cylindrical cavity of the swivel housing 4, in the gap between which the liquid medium 5. is placed on the supports 6 inside the gyrocamera 1 a gyroscopic sensor of 7 angular velocities is installed, the axis of sensitivity of which coincides with the axis of 3 gyrocameras. An axis sensor 9 is installed on the axis 8, the output of which is electrically connected to the input 10 of the amplifier 11. The output of the amplifier is connected to the control winding of the motor 12, in the circuit of which the recording device 13 is connected in series. The motor 12, through the gearbox 14, informs the rotary body 4 of a rotational motion relative to the axis 15.

The reference voltage generator 16 is connected to the second input 17 of the amplifier 11. The temperature sensor 18 is installed inside the rotary housing 4, the electromagnetic lock 19 is mounted on the end surfaces of the rotary housing and the gyro chamber. At the tertizes of the rotary body there are two fittings 2O and 21.

The viscosity meter works as follows.

The cavity between the gyro chamber 1 and the swiveling housing 4 through the introductory choke 20 is filled with the liquid under study 5.

, Mg N-s (1)

Where. H -: the kinetic moment of the rotor of the gyroscope;

04 - the angular velocity gyrocamera relative to the vertical axis 15, created by the engine 12.

The equation for the moment of friction viscosity force is determined by the extrusion

da

(2) Mv-f, -,

where f .. friction force viscosity coefficient;

and - the angle will turn the gyrocameras along the axis 3.

In the established motion. the following equality is fulfilled

da

d-t

(3)

(four)

It follows from formula (4) that the coefficient of viscous force is three, and, consequently, the viscosity of the liquid is directly proportional to the angular velocity of the body of the meter, provided

st

The angular velocity of the gyrocamera (dt) is stabilized by a regulator consisting of a gyro conical angular velocity sensor, an amplifier, and a motor. Structural diagram of the controller together with a gyroscope, a gyro camera and the liquid under study

presented in FIG. 2

The angular velocity of the movement of the camera is measured by means of a gyroscopic angular velocity sensor, the signal from which is compared with this one, the young voltage Us, which is selected during calibration of the instrument. The difference signal is amplified in the amplifier and then fed to the motor control winding 12, the speed of rotation of the output shaft of which is proportional to the current in the control winding.

Differential equations of motion of a gyrocamera

 da Ah f-- + Kga,

(five)

dt d-fc

where A is the moment of inertia of the gyrcamera relative to axis 3;

f is the coefficient of friction viscosity forces;

Cg is the coefficient of elastic forces. The equation of the gyroscopic angular velocity sensor (GDUS) measuring angular velocity

1 / gdus Cgdus,

(6)

Claims (2)

where Upflyc is the output voltage of the GDUS; Kr / v is the coefficient proportional to the Equation of the AU U3 Urflyc adder, (7 where and is the reference voltage. Equation of the amplifier and, KusLi gae Kus is the amplification factor of the voltage amplifier. Equation of the load 1nagr Knius, (9 where Ki is the load circuit transfer ratio. The equation of an electric motor with a gearbox is Р Ндв1нагр, where (OriKdv-, respectively, the speed and transmission ratio of an electric motor with a gearbox. Accelerated equation of a two-stage gyroscope / U, (11 where N (d, kinematic moment of the rotor of the gyroscope. In accordance with the formula (S) transfer function qi gyrocamera a (P) 1 Mg (P) Ap + fP + Kr (12 Taking into account the formula (1О), we take as an output value proportional to the viscosity of the liquid, the current in the load circuit of the electric motor, and as the value of - voltage O Then the block diagram can be represented in the form shown in Fig. 3, and in Fig. 3 the exact factor of the closed system Kus-Kn-f Kgdus-N Kdv-Ius-K ft-Krflyc-H-KflB-Ky is also given. The parameters of the controller are chosen so that f "KHKdvKuKgdus. (1 Then we get 1vagr Kgdus KjjgH, i.e., when and -const there is a linear relationship between the current in the load circuit (motor control winding) and the viscosity factor, and, consequently, the viscosity of the fluid. Measuring device (ammeter ) is calibrated in units of viscosity. During the measurement of viscosity, the locking mechanism periodically returns the camera to a zero positonion. The measurement of the temperature of the test liquid during the determination of the viscosity of the probe is determined by a microammeter included in the diagonal of the bridge formed by Toros and a thyristor placed inside the working cavity of the housing. Formula of the invention: A rotational viscometer containing a hydrokamsra installed in a cylindrical rotary housing, the gap between which is filled with the studied fluid, which is designed to improve measurement accuracy in a wide range of viscosity, it is additionally introduced in the stabilization controller of the speed of the angular motion of the gyrocamera, consisting of a gyroscopic sensor of angular velocity, a comparison signal amplifier, an electric motor Bonded via a reduction gear with the rotary body, and a reference voltage generator connected to the second input of the amplifier, said control winding motor connected to the output amplifier. Sources of information taken into account during the examination 1. Swiss patent, № 474О55, cl. G 01N M / 14, 1969. 2. The author's certificate of the USSR No 535481, cl. 0 01N 11/14.