SU1432388A2 - Rotary viscometer - Google Patents

Abstract

The invention relates to instruments for measuring rheological parameters, in particular to instruments for determining the viscosity of petroleum products, polymers, building materials, paints, and the like. The aim of the invention is to improve the measurement accuracy by compensating for the effect of non-uniformity of the no-load current of an electric motor. The device contains a direct current motor, on the shaft of which there is a working body immersed in the measured medium (for example, a cylinder), a control unit, a measuring unit, and an electric motor friction torque compensator. The introduction of an additional gain compensator, no-load current with speed and inertia forces makes it possible to improve measurement accuracy in a dynamic mode. The viscometer allows measurements to be made both at a given (including varying) rotational speed, and at a given (including changing) engine torque. 1 il. (L

Description

4 with to

00 00 00

1143

. The invention relates to instruments for measuring rheological parameters, in particular, instruments for determining the viscosity of petroleum products, polymers, building materials, paint, pepper solutions, and the like. and is an improvement of the invention on auth. No. 1343300.

,

Rotational viscometer works as follows.

The DC motor 2 rotates the indenter 1 immersed in the test substance. The mode of operation of the motor and the viscometer as a whole is set and provided by the control unit 23, which through the control

Rotational viscometer contains a working body (indenter) 1 in the form of a cylinder (disk, cone, blade and

The aim of the invention is to increase the voltage source 3 and measure the measurement accuracy by means of the com- puter unit 4, which controls the influence of the non-uniformity of the motor 2, on such a crust, as the idler of the electric motor. at which either the speed of rotation,

 The functional plot shows either a functional torque or an electric motor with a rotational viscometer circuit. 5 - corresponds to the specified block 23

control value. According to the structure, control unit 23, adder 20, adjustable voltage source 3, measuring unit 4 with electric motor T1.) Installed either directly 20 2, compensator 8 of the torque signal directly, or via a reducer from a high and compensator 11 signals increasing efficiency (not shown) on the shaft of the idling current electric motor from the speed and the dc motor 2, powering the inertia to form a closed one from an adjustable source 3. the automatic control system block 4e 25 rovani with back bond or by comprising a load resistor. 5 and rotational speeds, or in terms of torque, additional resistors 6 and 7, the moment of the electric motor, depending on the winding of the electric motor core on the position of the key 22. gate 2 according to the tachometric scheme. The signal supplied to the indicator 18 of the two 30-coordinate recorder 17, to the output 15 and to one of the inputs of the control unit 23 is proportional to the rotational speed of the electric motor, taken from the common point of the additional resistors 6 and 7, which together with the load resistor 5 and the resistance of the root winding of the electric motor 2 form a balanced tax bridge with a grounded common point of resistor 5 and the main winding of electric motor 2.

The signal, the current proportional, as well as the total electromagnetic moment of the electric motor, is removed from

bridge, the compensator 8 signal of the moment of friction, containing cyNn "5aTOp 9, to one input of which is connected a common point of resistors 5 and. 6, and to the second, a constant bias regulator 10, a compensator 11 of the idle current increment signal from speed and C1-III inertia, executed as a scale link 12, a differentiator .13, whose inputs are connected to a common point of additional resistors 6 and 7, and cyMJijaTop 14, two inputs of which are connected to the outputs of the scale link and differentiator, the rety input with the output of the adder 9, in: 15 and 16 signals of speed and torque, connected to the common point of resistors 6 and 7 and to the output of the sum of TC 14, two-coordinate registrato - 17, containing indicators 18 and 19 (grayness of rotation and torque, connected to output terminals 15 and 16, respectively, adder 20, the output of which is connected to the input of adjustable voltage source 3, and inputs to reference signal input 21 and the output of class 22 of control unit 23, two inputs of which are connected to output terminals 15 and 16.

35

40

45

50

55

ungrounded end of the load resistor 5..

The signal supplied to the indicator 19 of the two-axis recorder 17, to the Output 16 and to the second of the inputs of the control unit 23 is proportional to the torque of the indenter of the viscometer, subtracted from the signal proportional to the total electromagnetic moment of the electric motor, the following components motor idle signal: proportional to the initial frictional moment using an adder 9 and a constant displacement adjuster 10

45

50

55

ungrounded end of the load resistor 5..

The signal supplied to the indicator 19 of the two-axis recorder 17, to the Output 16 and to the second of the inputs of the control unit 23 is proportional to the torque of the indenter of the viscometer, subtracted from the signal proportional to the total electromagnetic moment of the electric motor, the following components motor idle signal: proportional to the initial frictional moment using an adder 9 and a constant displacement adjuster 10

compensator 8 (compensating for additive change density); proportional to the increase in idle current from the motor speed using an adder 14 and a scale link 12 of the compensator 11 (compensation for the multiplicative measurement error); proportional to the increase in the no-load current from the inertia forces of the electric motor using Sz mmator 14 and the differentiator 13 of the compensator 11 (compensation of the dynamic measurement error) ..

The setting of links 10, 12., and 13 of the effect of the irregularity of the current of the idle capacitors 8 and 11 is performed, experimentally at idle viscometer so that the signal at the output 16 at different speeds of rotation and angular acceleration of the electric motor is equal to or closest to zero.

connected to the common point of the additional resistors of the measuring unit and the third adder, two inputs of which are connected to the outputs of the scale. The information recorded by the two-coordinate recorder 17 serves to determine the viscosity, the curve of the 25 link and the differentiator, the third or other rheological harak-input - with the output of the second adder,

The characteristics of the substances under study are expressed as the output with the input of the signal being twisted through the rotational speed and the torque to the control unit.

indenter moment. If necessary, additional external devices are connected to the output terminals 15 and 16 to further process the output signals of the viscometer (for example, a micro-computer).

Claims (1)

Invention Formula Rotary viscometer according to ed. St. No. 1343300, characterized by the fact that, in order to improve measurement accuracy by compensating During the course of the electric motor, it is equipped with a compensator for the increase in the no-load current as a function of the speed and inertia forces, fulfilled in the form of a large-scale link, a distifier, whose inputs connected to the common point of additional resistors of the measuring unit and the third adder, two inputs of which are connected to the outputs of the scale link and the differentiator, the third input is connected to the output of the second adder, Compiled by V.Voschankin Editor O.Golovach Tekhred L.OliynykCorrector V.Romanenko . Order 5417/35 Circulation 847 VPIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 tf Subscription