RU2625535C1 - Vibrational structurometer - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: vibrational structurometer consists of an electromagnet with a cylindrical ferromagnetic core vertically mounted on the base by bracket, at the lower end of which there is a shank and a spring-loaded thrust disk with a hole, into which a guide of a stepped finger enters; along a larger diameter of which, there is a thread with an adjusting and locking nuts. The body of the hydraulic damper is located above the core. The body has a cylindrical chamber with a spring-loaded piston with a sealing cup placed at the top. The chamber is divided into an upper working and lower expansion tank by the disk with a central calibrated hole pressed into it. The expansion tank is provided with an air threaded valve, and on top of the piston there is a central protrusion contacting the cramp which lower end is fixed at the upper end of the core. On the shank of the core a body of a tensometric dynamometer is fixed, whereto a measuring rod equipped with a pressure plate is attached.

EFFECT: simplified design of the instrument and improved measurement accuracy.

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Description

The invention relates to devices for continuous monitoring of the process of gel formation during milk coagulation in the production of cheeses and fermented milk products. In addition, the vibrational structuremeter can be used to control the gelation processes in the production of other products, as well as in the biological, chemical and other industries.

Known oscillatory shiftometer [1], comprising a housing, a base on which a loading device is mounted, consisting of a stepper motor, on the shaft of which a cam is mounted, made in the form of a sleeve, to which a disc is attached with adjustable eccentricity through two slots made in it along the centerline. A ball bearing is pressed onto the disk, the outer ring of which is in contact with a plate of a hollow spring-loaded plunger installed in the central sleeve attached to the base with the possibility of translational movement.

The measuring device consists of a calibrated cylindrical coil spring, fixed with the upper coil with an arm to the lower end of the hollow pusher, and with the lower coil - with an arm fixed to a measuring rod coaxial to the hollow rod, installed on two precision bearings, at the lower end of which there is a sensing element in the form vertically located grooved on both sides of the plate. At the same time, the upper precision bearing is mounted on a plate attached to an arm mounted on the base, and the lower one is in a cup fixed coaxially on the central bushing.

The meter of the controlled parameter (linear displacements of the sensing element) is fixed coaxially to the measuring rod on an arm mounted on the base and includes a permanent magnet made in the form of a cylinder of circular cross section with a flat disk glued on top of an annular shape, into which a core is pressed coaxially to the permanent magnet . Moreover, the disk and the core are made of mild steel. In the annular gap between the permanent magnet and the core with a gap and coaxially inserted mounted on the upper end of the measuring rod coil with a winding, the findings of which are connected to the processing unit of the measurement results.

The disadvantage of the considered rheometer is the design complexity, namely the presence of a measuring rod, a coil with a winding and a composite permanent magnet with an annular gap, which in the manufacture, adjustment of the rheometer and its maintenance require high qualification. Also, the use of two bearings will cause noticeable friction losses in this assembly, which will lead to a decrease in the accuracy of the measurement results.

The closest technical solution that we have chosen as a prototype is a rheometer containing a loading unit, consisting of a sleeve fixed perpendicular to the base of the sleeve, in the bearings of which a rod is moved, at the lower end of which a horizontally positioned loading disk is fixed, and is mounted coaxially and parallel to the bottom of this disk a reflector disk, attached with three studs arranged with equal pitch around the circumference, to a plate fixed on the lower end of the central sleeve, and on top on the bases SRI mounted counterbalancing device consisting of a removable cargo connected with a flexible coupling rod from transfer through the block mounted in a precision ball bearing on the L-shaped bracket secured to the base. To create loading on the base, a geared motor is mounted perpendicular to the rod on the L-shaped bracket with a cam moving the rod through the antifriction sleeve fixed on it.

The measuring unit contains a cam mounted on the shaft of the geared motor controlling the limit switch of the inductive linear displacement sensor, the core of which is fixed on the rod, and its body is attached to the L-shaped bracket. At the same time, to prevent angular displacements of the loading disk, a rod with a precision ball bearing installed with a minimum clearance in the longitudinal groove of the central sleeve [2] is installed on the rod.

The disadvantage of the rheometer is, first of all, the complexity of the design, namely the presence of a gear motor used to create loading, for which angular velocity regulation is not provided. This complicates the possibility of changing the oscillation frequency and can lead to a decrease in accuracy. In addition, the use of an inductive sensor as a displacement meter complicates the design and thereby reduces the reliability of the rheometer. This complicates the maintenance process of the rheometer.

The objective of the invention is to simplify the design of the device and improve the accuracy of measurements.

The essence of the invention lies in the fact that in an oscillating structuremeter containing a base, a loading device, a force measuring device and a control unit, the loading device consists of a vertically fixed electromagnet with a bracket, including a steel cylindrical cup with a power coil, closed by a steel threaded cover, bushings made of antifriction material, in which a cylindrical ferromagnet is mounted, are pressed into the central holes of the bottom of the glass and the lid a core with a shank at the lower end and a spring-loaded thrust disk with a hole in which, with a minimum clearance, a step pin guide is inserted that is pressed perpendicularly to the base, on a larger diameter of which there is a thread with adjusting and locking nuts, and attached to it and coaxially attached to the core screws to the bracket perpendicular to the base of the hydraulic damper housing, in the lower part of which there is a flange closed by a membrane, tightly attached connected to it with a clamping ring with screws. In this case, a cylindrical chamber closed with a spring-loaded piston with a sealing sleeve and filled with liquid and divided into an upper working and lower expansion tank by a pressed disk with a central calibrated hole in which a tapered recess is made from below is made in the housing, and the expansion tank is equipped with an air threaded valve, and on top of the piston there is a central protrusion in contact with the bracket, the lower end of which is fixed on the upper end of the core.

The force measuring device consists of a strain gauge mounted on the core core of the housing, to the output link of which is connected a measuring rod equipped with a horizontally and coaxially arranged pressure disk, and a reflective disk mounted coaxially to the base using three height-adjustable studs screwed in with equal pitch around the circle into the base.

In FIG. 1 shows a diagram of an oscillatory structuremeter; in FIG. 2 - view A; in FIG. 3 - view B; in FIG. 4 - comparative rheograms of the controlled parameter “longitudinal elastic modulus E is the duration of the process t” of formation of acid rennet clots obtained on the proposed invention (curve 1) and on the prototype [2] (curve 2).

The oscillating structuralometer (Fig. 1) has a base 1 on which an electromagnet is mounted vertically on the base 2 with a bracket 2, including a steel cylindrical glass 3 with a power coil 4, closed by a steel threaded cover 5. The bushings are pressed into the central holes of the bottom of the glass 3 and cover 5 made of antifriction material 6 and 7, in which a cylindrical ferromagnetic core is installed 8. At the lower end of the core there is a shank 9 and a thrust disk 10 with a hole 11. On the disk, a centering protrusion 12 is made, the contact with a cylindrical coil spring 13. To ensure axial movement of the core 8, a guide 14 of the stepped pin 15 is inserted into the hole 11 with a minimum clearance, pressed in perpendicularly to the base, the larger diameter of which has a thread with adjusting 16 and lock nut 17 (Fig. 2) , limiting the working stroke (δ) of the core 8. To ensure smooth movement of the core 8, above it and coaxially to it is located attached by screws to the bracket 2, perpendicular to the base 1, the hydraulic housing vlicheskogo damper 18 (hereinafter - damper) (FIG. 3). In the lower part of the housing 18, a flange 19 is provided, closed by a membrane 20 sealed to it by means of a clamping ring 21 with screws. At the same time, in the housing 18, a piston 23 closed with a spring-loaded coil spring 22 and with a sealing sleeve 24 is made, a cylindrical chamber filled with a liquid (mineral oil or glycerin) and divided into an upper working 25 and lower expansion tank 26 by a disk 27 pressed into it. In the disk 27 a calibrated hole 28 is made in the center, and a tapered recess 29 is provided at the bottom, and the expansion tank 26 is equipped with an air threaded valve 30. At the top of the piston 23 there is a central protrusion 31 in contact with wallpaper 32, the lower end of which is fixed at the end of the core 8.

The force measuring device consists of a core 8 of the strain gauge housing 33 mounted on the shank 9, to the output link of which a measuring rod 34 is attached, equipped with a horizontally and coaxially arranged pressure disk 35, and a reflector disk 36 attached to the base with a parallel and coaxially mounted three height-adjustable studs 37 screwed with an equal pitch around the circumference into the base 1. As a tensometric force meter 33, a standard precision strain gauge is used esky electronic unit analytic laboratory balance, mass-produced. For example, Sartorius Secura Series Laboratory Scales http://www.sartogosm.ru/sartorius_serii_secura.html

To ensure the tightness of the nodes of the oscillatory structuremeter during its sanitary treatment, a protective casing 38 and a corrugated cuff 39 are provided, worn on the shank 9 of the core 8, attached to the base 1.

Liquid filling of the damper (mineral oil or glycerin) is carried out in the following sequence:

- remove the damper housing 18 from the bracket 2 by unscrewing the screws;

- take out the piston 23;

- open the air threaded valve 30;

- place the damper vertically above the vessel (not conventionally shown) to collect excess fluid;

- pour liquid from above into the working container 25, which is poured through the central calibrated hole 28 of the disk 27, fills the lower expansion tank 26 and pushes air through the air threaded valve 30. Moreover, the diameter of the central calibrated hole 28 is guaranteed to be larger than the diameter of the air threaded valve 30. Conical recess 29 Designed to withdraw residual air bubbles through a central calibrated hole 28 from the expansion tank 26 as it is filled;

- when the working container 25 is completely full, insert the piston 23 and lower it to the bottom until its end coincides with the upper end of the damper body 18. In this case, excess liquid will be discharged into the vessel;

- screw the air threaded valve 30;

- fasten the damper housing 18 to the bracket with 2 screws.

The rheometer works as follows. It is fixed strictly vertically on the side wall of the process bath with a special bracket (not conventionally shown in the drawing), so that the pressure plate 35 and the disk reflector 36 are completely immersed in a controlled environment.

Connect the connectors of the strain gauge and the electromagnet network cable to the control unit (not shown conditionally), which is then connected to the network. Because a tensometric force meter is used in the measuring unit, then in the measuring electric circuit a bridge circuit for recording its signal is used, which requires balancing the measuring bridge, in which the readings of the linear displacement indicator are “zeroed”. In the control unit, the time relay sets the time interval through which a short circuit will occur - circuit opening and next measurement (usually the next measurement cycle step is set to 30 s). At the initial time, the core 8 occupies its highest position, and with the help of the adjusting 16 and locking 17 nuts, the working stroke 8 of the core is established. The rheometer is ready for operation.

The process of controlling gel formation during milk coagulation. From the control unit panel, by pressing the “Start” button, voltage is applied to the power coil 4 of the electromagnet, due to the electromagnetic field generated in the space of the coil, the core 8 will begin to translate, thereby through the shank 9 with the thrust disk 10, the housing of the strain gauge 33, the measuring rod 34 transmit translational movements to the pressure disk 35 immersed in a controlled environment. Having made the movement by the set value of 5, within the set time (5 s), the circuit supplying the electromagnet will open, the return spring 13, pushing the thrust disk 10, will return the rod 8 to its original position, after a predetermined time (30 s) the circuit will close and repeat measurement cycle.

At the same time, the design of the developed vibrational structuremeter for continuous monitoring of the gel formation process during milk coagulation in the production of cheeses and fermented milk products allows it to be used as an element of the automatic control system for the production process, as well as a laboratory device for the development of new types of cheeses, etc. products.

In FIG. 4, for example, two comparative rheograms of “Е-t” for the formation of rennet and sour milk clots obtained on the proposed vibrational structuremeter (curve 1) and on a rheometer for monitoring the formation of acid-rennet clot (curve 2) of Kemerovsky soft cheese according to the recipe and technology are presented Kemmolprom (Kemerovo city). On both rheograms, three temporary sections characteristic for this process are clearly distinguished: AB - stage of induction (liquid milk mixture); BC - flocculation stage (the beginning of floc formation, volumetric structure and hardening of the clot) CD is the stage of metastable equilibrium (reaching the maximum strength of the clots at points C, rheograms suffer a kink and go to a horizontal section - the strength of the clots does not change). From the analysis of the rheograms, it can be seen that they have a similar character, however, on the rheogram obtained on an oscillatory structuremeter, the CD section has a steeper characteristic, which indicates the receipt of more accurate values of the modulus of longitudinal elasticity E.

Information sources

1. Pat. 2454655 Russian Federation, IPC ⁷ G01N 11/14. Vibration rheometer / A.N. Pirogov, I.A. Litvinova; Applicant and patent holder GOU VPO Kemerovo Institute of Food Technology. - No.2008130243 / 28; announced 12.01.11; publ. 06/27/12. Bull number 30.

2. Pat. 2304280 Russian Federation, IPC G01N 33/04. Rheometer for the formation of acid rennet clot / A.N. Pirogov, D.V. Donya; Applicant and patent holder Kemerovo Technological Institute of the Food Industry. - No.2008130243 / 28; Declared 08/01/05; publ. 08/10/07. Bull number 30.

3. Rheometry of food raw materials and products: Handbook // Ed. Machikhina Yu.A. - M.: Agropromizdat, 1990 - 271 p.

Claims (1)

An oscillating structuralometer containing a base, a loading device, a force measuring device, and a control unit, characterized in that the loading device consists of a vertically fixed electromagnet with a bracket, including a steel cylindrical glass with a power coil, closed with a steel threaded cover, and in the central holes of the bottom cups and covers are pressed in sleeves of antifriction material in which a cylindrical ferromagnetic core is installed, having the lower end of the shank and the spring-loaded thrust disk with a hole in which the guide of the stepped pin pressed into the base with a minimum clearance enters, the larger diameter of which has a thread with an adjusting and locking nut, and above the core and coaxially attached to it is attached to the bracket bracket, perpendicular installed on the base, the hydraulic damper body, in the lower part of which a flange is provided, closed by a membrane hermetically attached to it with pressure ring with screws, while in the case there is a cylindrical chamber closed on top with a spring-loaded piston with a sealing collar, filled with liquid and divided into an upper working and lower expansion tank by a pressed disk in it, in which a calibrated hole is made in the center and a conical undercut in the bottom, and the expansion tank is equipped with an air threaded valve, and on top of the piston there is a central protrusion in contact with the bracket, the lower end of which is fixed at the upper end with core, and the load-measuring device consists of a strain gauge mounted on the core core of the housing, to the output link of which is connected a measuring rod equipped with a horizontally and coaxially arranged pressure disk, and a reflector disk attached to the base by means of three axially mounted parallel to it using three adjustable the height of the studs screwed in with equal pitch around the circle into the base.

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