SU721704A1 - Viscosimeter - Google Patents

Description

(54) VISKOSIMETER

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The invention relates to devices serving to study the rheological properties of liquids of various types often encountered in food processing. The basis is the properties of the viscometer of a physical man, which damps oscillations in the test fluid.

A device for determining the viscosity of liquids is known, the principle of which is to measure the damping factor 1, for example, Rosin G. S. viscometer.

The closest technical solution to the present invention is the Meisels 2 viscometer, which consists of a frame, a pendulum having a removable disk immersed in the test liquid, a vessel containing it, a visual device for reading on a scale of deflection angles, two stop rods defining the maximum span, and a mercury chopper, which is used to record the number of the oscillations of the pendulum when attenuated in a certain range of amplitudes.

Such a viscometer can be used in determining the viscosity of liquids with a constant consistency, since

as it changes, the number of oscillations of the tartrum also varies, with the result that the measurement error increases. It does not allow the study of the rheological properties of liquids under overpressure or discharge. Observation of attenuation of oscillations of the tambour from the original span to some smaller angle in a visual manner does not provide high accuracy of measurements. In addition, the viscometer has an imperfect system for the command of the initial amplitude and the output of the model from the deflected position.

When changing the structural and mechanical properties of liquids, it is necessary to replace the working fluid (removable disk), immersed in the test liquid. Variation of the working fluid area allows the measurement to be extended. However, in this case, when calculating the viscosity, there are certain difficulties associated with changes in the flow conditions of the working fluid.

Claims (2)

body. Thus, with each replacement of the working fluid, it is necessary to make an experimental determination of the permanent devices (the first - when observing the damping of the tambourine's oscillations in the air, the second - in the reference liquid of known viscosity). This is almost impossible under production conditions characterized by continuous changes in the rheological properties of controlled liquids, for example, semi-finished bakery products. The aim of the invention is to increase the reliability of determining the viscosity of liquids with different rheological properties (for example, liquid brew, yeast, sourdoughs, chocolate mass, syrups, cream, etc.) due to the possibility of changing the moment of inertia of the trough by means of additional weights with a constant working body . In order to achieve this goal, in the proposed viscometer, a rod is rigidly fixed on one axis with a bowl, on which additional weights are placed, the mass of which is caused by the structural and mechanical properties of the tested liquids. FIG. 1 shows the proposed viscometer; in fig. 2 shows section A-A in FIG. one; in fig. 3 shows a section BB in FIG. 2. The main elements of the viscometer (see Fig.}) Are a hermetically sealed housing consisting of two parts of the lower 1 and upper 2, the pilot 3, the sensor of 4 angular displacements, the device 5 for setting the pilot to the initial deflection and withdrawing it from this position (toothed sector). In the lower part of the body there is a bath 6 for the test liquid, the temperature stabilization of which is achieved by installing a water jacket 7 having outlet and outlet nozzles 9. The body is sealed when the upper part is pressed to the bottom with bolts 10. Pot 3 is a working fluid 11 ( for example, a sphere) connected by a small cross-section rod with an axis 12, which is mounted in supports 13. In addition, a perforated disk of a photoelectric sensor 4 of rotation angles, a toothed sector 5 and a rod 14 are rigidly fixed on an axis 12, on which removable loads 15 are moved. Gear sector 5 is in engagement with the pin of the lever 16, and the closing force of this kinematic pair is adjusted through the spring with a screw 17 (Fig. 2). The movement of the lever 16 and the sector 5 is caused by the cam 18, which is fixed on the axis of the handle 19 located outside the housing. By turning the cam 18 (counter-clockwise in the drawing), you can move sector 5 at a certain angle, i.e., set the initial deflection of the indicator 3. The device works as follows. The test liquid is placed in a bath 6, the water jacket 7 of which is attached to a thermostat. To study the rheological properties of liquids of different consistency in. The device provides for the possibility of changing the moment of inertia of the tandem with the help of additional weights 15. After installing the corresponding additional cargo, if necessary, compressed air is supplied through the nozzle 20, the pressure created by it is controlled by a pressure gauge 21. The initial pressure is produced by turning the knob 19 to position that corresponds to the rotation of the toothed sector 5 at the desired angle (not exceeding 8 °). Leaning the tilt from the deflected position, turning the handle 19, and hence the cam 18 in the reverse direction (in the drawing, clockwise), as a result of which the lever 17 rotates and the pin disengages from the teeth of sector 5 freeing the master The angular movement of the tangent is recorded in time by a photoelectric sensor, the signals of which are continuously recorded on a high-speed device. Having obtained the logarithmic damping decrement and the oscillation period of the tandem in the test fluid, as well as the values of the constant devices, the fluid viscosity can be calculated. It should be noted that in order to repeat the experiment, the initial deviation of the pendulum is carried out in the described sequence without depressurization of the chamber, which is especially valuable when testing liquids whose properties vary with time, for example, liquid sponge during its fermentation. Claims The viscometer includes a sealed case, a master, a control mechanism, a measuring system and a thermostatic jacket, characterized in that, in order to expand the range of viscosities of the test media, the rod on which the interchangeable weights are placed is fixed on the axis. Sources of information taken into account in the examination 1. "Factory Lab, 1967, 33, № 8. 2. USSR patent number 8334, cl. G 01 N 11/16, 1924 (prototype). y / 7 // 7 // 7 // 7 /// 7/7 /// 77 // 7 / L // 7 //////////////////// /////BUT .one