JP2013242297A - Viscosity measurement device and measurement method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a viscosity measurement device in which the quantity of a sample, which is a substance to be detected, is smaller than the conventional quantity, which is smaller than the conventional device and in which viscosity of a substance having low viscosity of around 10 cP or lower can be measured more accurately than the conventional device, and a method of the same.SOLUTION: A viscosity measurement device of this invention includes: a container which contains a substance to be measured; a spherical rotor which is formed by a conductive material, is immersed in the substance to be measured, and is arranged being in contact with the bottom of the container; a magnet; a rotating magnetic field control unit; and a viscosity detection unit. The rotating magnetic field control unit gives a rotating magnetic field to the rotor by the magnet, excites an induction current to the rotor, gives a rotation torque to the rotor by the Lorentz interaction between the induction current and the magnetic field applied to the rotor, and controls the magnetic field in such a manner that the rotor moves in circulation, according to the rotation of the rotating magnetic field. The viscosity detection unit detects the viscosity of the substance to be measured by the number of circulation of the circulation movement of the rotor.

Description

  The present invention relates to a viscosity measuring apparatus and a measuring method for measuring viscosity, which is a mechanical property of a substance.

Conventionally, measurement of viscosity and elasticity has been performed in order to detect the mechanical properties of a target substance (see, for example, Patent Document 1).
Viscosity and elasticity are measured in the manufacturing process of pharmaceuticals, foods, paints, inks, cosmetics, chemical products, paper, adhesives, fibers, plastics, beer, detergents, concrete admixtures, silicon, etc., quality control, performance evaluation, It is an indispensable measurement technology for raw material management and research and development.

Conventionally known methods for measuring viscosity include the following methods.
(1) Viscosity tube method, (2) Method of contacting vibrator, (3) Method of using surface acoustic wave, (4) Method of using rotor, (5) Method of dropping hard sphere, (6) Motion Light scattering method, (7) Zimmm type viscosity measurement method, and (8) EMS (Electro Magnetically Spinning) viscosity measurement method.

JP 2005-69872 A

However, among the methods described above, the methods (1) to (5) require a large amount of sample (substance to be measured) of several cc or more.
In particular, with respect to the methods (2) to (5), accurate measurement cannot be performed unless the viscosity (viscosity coefficient, ie, viscosity) of the sample is at least 10 cP or more. Therefore, the methods (2) to (5) above cannot accurately measure the viscosity of a material having a viscosity lower than 10 cP.
Furthermore, regarding the method (6), the measuring apparatus is large-scale. In addition, the method (6) needs to transmit light to such an extent that the measurement accuracy can be maintained, and therefore cannot be applied to other than transparent samples.

  Regarding the method (7), it is an essential condition that the cylindrical rotor is placed in the sample in an upright state. If the wettability of the rotor with respect to the sample is not uniform over the entire surface of the rotor, the rotor cannot be erected in the sample. For this reason, in the method (7), when measurement is performed while maintaining the rotor by buoyancy, the rotor is maintained in an upright state due to non-uniform wettability of the rotor with respect to the sample. It becomes difficult.

Regarding the method (8), the rotor contacts the bottom of the container containing the rotor and the sample and rotates. For this reason, friction occurs at the contact point between the rotor and the container, and an error for measuring the viscosity occurs. Therefore, with the method (8), due to the measurement error caused by this friction, a highly accurate measurement can be performed on a sample having a viscosity of at least 10 cP, as in the methods (2) to (5). I can't do it.
In the method (8), since the rotation of the rotor completely buried in the sample in the container is observed, it is necessary to transmit light to the extent that the measurement accuracy can be maintained. Therefore, a sample other than the transparent sample, for example, a black sample cannot be measured.
In the method (8), the rotation of the rotor in the sample may be observed using laser scattering. However, since samples such as colloids and slurries generate strong scattered light as reflected light, samples such as colloids and slurries cannot be measured when laser scattering is used.

  Furthermore, with respect to the methods (7) and (8) above, the magnet that generates the rotating magnetic field rotates along the side wall of the container in which the sample is placed. For this reason, it is necessary to ensure the area | region where a magnet rotates in the outer peripheral part of the side wall of a container. Therefore, when configuring a temperature control device for controlling the sample temperature in the container, an electric field application device, or the like, the device becomes large.

  For the reasons described above, in the methods described in the above (1) to (8), universal physical quantities such as viscosity and elasticity of liquids and other soft materials (soft matter), that is, mechanical It is difficult to easily measure a physical quantity with a small amount of sample. Moreover, in the method described in said (1)-(8), it is difficult to measure with high precision about a low-viscosity sample. In addition, in the methods described in the above (1) to (8), there is a limitation in downsizing the apparatus.

  The present invention has been made in view of such circumstances, and can reduce the amount of a sample, which is a substance to be measured, as compared with the conventional technique, and can reduce the size of the apparatus as compared with the conventional technique. It is an object of the present invention to provide a viscosity measuring apparatus and a measuring method thereof capable of measuring the viscosity of a low-viscosity substance having a viscosity of about 10 cP or less with higher accuracy than before.

  According to the first aspect of the present invention, the viscosity measuring device is formed of a container in which a measurement target substance whose viscosity is to be detected is placed, a conductive material, and sinks in the measurement target substance. A spherical rotor disposed in contact with the bottom of the container; a magnet that applies a magnetic field to the rotor; a rotating magnetic field control unit that orbits the rotor; and the rotation of the rotor A viscosity detector that detects the viscosity of the substance to be measured based on the number of movements. The rotating magnetic field control unit applies a rotating magnetic field to the rotor by the magnet, induces an induced current in the rotor, and performs the rotation by Lorentz interaction between the induced current and a magnetic field applied to the rotor. A rotational torque is applied to the rotor, and the rotating motion of the rotor is controlled in accordance with the rotation of the rotating magnetic field.

  According to the second aspect of the present invention, in the viscosity measuring device according to the first aspect, the orbiting motion is a circular motion in which the rotor rolls on the bottom of the container.

  According to a third aspect of the present invention, in the viscosity measurement device according to the second aspect, the container has a circular circulation path configured as a groove at the bottom of the region filled with the measurement target substance. And the rotor performs a circular motion along the circulation path.

  According to a fourth aspect of the present invention, in the viscosity measuring device according to the third aspect, the circulation path is configured by a groove surrounded by outer and inner side walls provided with respect to the bottom of the container. ing.

According to the fifth aspect of the present invention, in the viscosity measuring device according to any one of the first to fourth aspects, the vertical component B _z of the magnetic field on the circuit path received by the rotor and along the circuit path When the component B _θ is the angular velocity of the rotating magnetic field, B ₀ is the magnetic field of the magnet, θ is the declination of an arbitrary point in the circuit path, t is time, and n is a natural number, The magnetic field is a magnetic field represented by the following formula.
B _z = B ₀ · cos (ωt−nθ) (1)
B _θ = B ₀ · sin (ωt−nθ) (2)

  According to a sixth aspect of the present invention, in the viscosity measurement device according to any one of the third to fifth aspects, the rotating magnetic field is equivalent to the rotor at any position of the circuit path. As the magnetic field advances on the circuit path, the direction of the magnetic field at each traveling position rotates in a vertical plane including a tangent on the circumference in plan view of the circuit path.

  According to a seventh aspect of the present invention, in the viscosity measuring device according to any one of the third to sixth aspects, the path of the rotor that circulates in the bottom of the container is a horizontal plane.

  According to an eighth aspect of the present invention, in the viscosity measurement device according to any one of the first to seventh aspects, the rotating magnetic field control unit has N poles on the arrangement surface perpendicular to the rotation axis of the rotating magnetic field. A rotating magnetic field to be applied to the rotor is generated by rotating a magnet fixing base in which a plurality of permanent magnets are arranged so that the upper surface and the south pole are alternately on the upper surface.

  According to a ninth aspect of the present invention, in the viscosity measuring apparatus according to the eighth aspect, the magnet is composed of a permanent magnet, and the magnet is rotated in parallel with the arrangement surface about the rotation axis. The rotating magnetic field to be applied to the rotor is generated.

  According to a tenth aspect of the present invention, in the viscosity measuring apparatus according to any one of the first to seventh aspects, the magnet is configured by an electromagnet, and the rotating magnetic field control unit is arranged in the electromagnet. The electromagnet is driven so as to change the polarity with time so that the polarity of the rotating magnetic field is different from that of the other adjacent electromagnets, thereby generating the rotating magnetic field.

  According to the eleventh aspect of the present invention, in the viscosity measuring apparatus according to the seventh or eighth aspect, the magnet is disposed in the upper part or the lower part of the container and in parallel with the surface of the substance to be measured. .

  According to a twelfth aspect of the present invention, the viscosity measuring apparatus according to any one of the first to eleventh aspects further includes a rotation detection unit that measures the number of times the rotor circulates, The viscosity detection unit obtains the viscosity of the measurement target substance based on the relationship between the number of rotations of the rotating magnetic field and the number of rotations of the rotor.

  According to a thirteenth aspect of the present invention, the viscosity measuring apparatus according to the first to twelfth aspects includes the number of rotations of the rotor in a plurality of reference materials whose viscosities are known in advance, and the rotational magnetic field. A standard data storage unit that previously stores, as standard data, a correspondence relationship between the rotation speed and the viscosity of the reference material, and the rotation number of the rotor in the measurement target material measured by the viscosity detection unit, and the rotation The rotational speed of the magnetic field is compared with the standard data to determine the viscosity of the measurement target substance.

  According to a fourteenth aspect of the present invention, in the viscosity measurement device according to the twelfth aspect, the rotation detection unit detects the number of rotations of the rotor by optical measurement.

  According to a fifteenth aspect of the present invention, in the viscosity measurement device according to the twelfth aspect, the rotation detection unit detects the number of rotations of the rotor by electrical measurement.

  According to a sixteenth aspect of the present invention, in the viscosity measurement device according to any one of the first to fifteenth aspects, the measurement target substance is a liquid or a soft material.

  According to the seventeenth aspect of the present invention, there is provided a method for measuring a viscosity, comprising: forming a conductive material in a container containing a target substance to be detected for viscosity; sinking in the target substance; A process of applying a magnetic field by a magnet to a spherical rotor arranged in contact with the bottom of the container, and applying a rotating magnetic field to the rotor by the magnet, inducing an induced current in the rotor, A process of giving a rotational torque to the rotor by Lorentz interaction between the induced current and a magnetic field applied to the rotor, and causing the rotor to make a revolving motion corresponding to the rotation of the rotating magnetic field; And detecting the viscosity of the substance to be measured based on the number of rounds of the round motion of the rotor.

  According to the above-described viscosity measuring apparatus and its measuring method, the rotor is submerged in the substance to be measured filled in the container, and a rotating magnetic field is applied to the rotor. Due to the Lorentz interaction between the current induced in the rotor by the rotating magnetic field and the rotating magnetic field, the rotor is caused to make a circular motion in the measurement target substance. The viscosity of the substance to be measured is measured by the number of revolutions per unit time of the rotor. Therefore, it is only necessary that the container is filled with the substance to be measured only in the portion where the rotor circulates. For this reason, compared with the past, the quantity of a measuring object substance required for a viscosity measurement can be decreased.

  In addition, according to this viscosity measuring apparatus and its measuring method, since the rotor rolls around the bottom of the container and makes a circular motion, the mechanical loss is limited to a slight loss due to the rolling friction of the rotor with respect to the bottom of the container. The Therefore, the mechanical loss is sufficiently small compared to the sliding friction due to the surface contact between the rotor and the bottom of the container. For this reason, the above-described viscosity / elasticity measuring apparatus and measurement method can reduce mechanical loss that suppresses rotation due to contact between the rotor and the container, and can further reduce measurement errors. . As a result, the above-described viscosity / elasticity measuring apparatus and measuring method can measure the viscosity of a low-viscosity material having a viscosity of 10 cP or less with higher accuracy than in the past.

It is a figure which shows the structural example of the viscosity measuring apparatus which concerns on 1st Embodiment of this invention. FIG. 3 is a conceptual diagram showing a state in which a sample 100 is placed in a sample container 2 and a conductive ball 1 is submerged in the sample 100. It is a figure which shows the other structural example of the sample container 2 which concerns on this embodiment. FIG. 4 is a diagram illustrating an arrangement example of magnets on the magnet fixing base 7 as viewed from above. 4 is a plan view showing a positional relationship between a first magnet 31, a second magnet 32, a third magnet 33 and a fourth magnet 34 arranged on the magnet fixing base 7 in the present embodiment, and a circulation path 23 in the sample container 2. FIG. . It is a graph which shows the relationship between the quantity related to the torque in the standard sample which has several different viscosity, and the revolution angular velocity (omega | ohm) _s of the conductor ball | bowl 1. It is a graph which shows a response | compatibility with viscosity (mPa * s) and inclination "((omega) _M + (1-R / r) * (omega | ohm) _s ) / (ohm) _s " for every standard sample from which viscosity differs. A method for applying rotational torque to the conductor ball 1 by a rotating magnetic field generated by the rotation of four magnets of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 will be described. It is a conceptual diagram. It is a figure which shows the electromagnet by which the yoke 10 and the teeth 10a, 10b, 10c, and 10d which protruded from this yoke 10 are arrange | positioned on the reference | standard two-dimensional plane.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration example of a viscosity measuring apparatus according to the first embodiment of the present invention.
The viscosity measuring apparatus according to the present embodiment includes a conductor ball 1 (rotor), a sample container 2, a first magnet 31, a second magnet 32, a third magnet 33, a fourth magnet 34, a motor 4, a rotation detection sensor 5, and a sample. A base 6, a magnet fixing base 7 and a viscosity measuring unit 8 are provided. Hereinafter, the case where the viscosity as a mechanical property of a substance, that is, the viscosity coefficient is measured by a viscosity measuring device will be described.

  The sample 100 is a substance to be measured, and is, for example, a liquid, a slurry, or a soft material. Soft materials are a group of molecular substances such as polymers, liquid crystals, colloids, and biomolecules. The colloid is, for example, an emulsion such as an emulsion, emulsion, or sol. Biomolecules are, for example, biological membranes, proteins, DNA and the like.

  The sample container 2 is a container in which a sample as a measurement target substance for measuring viscosity as a mechanical property is placed. As the sample container 2, for example, a small petri dish or the like can be used.

  FIG. 3 is a conceptual diagram showing a state in which a sample 100 is placed in a sample container 2 and a conductive ball 1 is submerged in the sample 100. FIG. 2A is a perspective view of the sample container 2. FIG. 2B is a top view of the sample container 2. FIG. 2C is a cross-sectional view of the sample container 2 taken along the line AA in FIG. As shown in FIGS. 2A, 2B, and 2C, the sample 100, which is the above-described measurement target substance, is placed in the sample container 2. Then, the conductor sphere 1 that is a conductive spherical rotor is submerged in the sample 100.

  As shown in FIG. 2A, the sample container 2 has a groove-shaped circulation path 23 sandwiched between a side wall 21 (outer wall) and a side wall 22 (inner wall). The circuit path 23 is formed in a size that allows the conductor ball 1 to travel. As shown in FIG. 2B, the circular path 23 has a circular path in plan view. Moreover, as shown in FIG.2 (c), the circulation path 23 is comprised as a groove | channel with a cross-sectional structure substantially rectangular shape. Further, as shown in FIG. 2B, the width L of the circulation path 23 only needs to be slightly larger than the diameter of the conductor sphere 1 submerged in the sample 100.

  In addition, a predetermined amount of the sample 100 stored in the circulation path 23 is injected into the sample container 2. The amount of the sample 100 to be injected into the sample container 2 may be an amount that allows the conductor ball 1 to completely sink into the sample 100. In the case of this embodiment, the sample 100 is injected in such an amount that the depth of the sample 100 in the state where the sample 100 is injected into the sample container 2 is deeper than the diameter of the conductor sphere 1. Further, the circulation path 23 is configured such that the bottom 24 is a horizontal plane. The circulation path 23 is configured such that the bottom 24 is horizontal with respect to the liquid level of the sample 100 filled in the sample container 2.

In this embodiment, as shown in FIG. 2B and FIG. 2C, the circular path 23 has an outer diameter r ₁ (the surface of the outer wall 21 on the side of the circular path 23 with respect to the conductor ball 1 having a diameter of 2 mm. ) Is 17 mm, the inner diameter r ₂ (radius on the surface of the inner wall 22 on the circumference path 23 side) is 12 mm, that is, the width L is 5 mm, and the depth D is 3 mm. In the present embodiment, as shown in FIG. 2C, the circuit path 23 has a flat bottom surface 24 and a rectangular cross section, but the cross section may be formed in a U shape. .

Next, FIG. 3 is a diagram illustrating another configuration example of the sample container 2 according to the present embodiment. FIG. 3A is a perspective view showing the outer shape of the sample container 2 of another configuration example of the present embodiment. FIG. 3B is a cross-sectional view taken along the line AA in FIG.
As shown in FIG. 3B, the cylinder 500 is a tubular member formed in an annular shape and having a hollow portion.

  In addition, the sample 500 is accommodated in the cylinder 500 at the lower part of the hollow portion. The conductor ball 1 is immersed in this sample 100 so that it can run. That is, in the sample container 2 shown in FIGS. 3A and 3B, the lower part of the inner peripheral wall of the cylinder 500 is the circulation path 23. At this time, the inner diameter of the cylinder 500 needs to be larger than the outer diameter (diameter) of the conductor sphere 1.

  The conductor sphere 1 is made of aluminum having a diameter of 2 mm, for example. When the specific gravity of the sample 100 is a liquid or soft material larger than aluminum, a conductor having a specific gravity larger than that of the liquid, such as a metal sphere such as brass, is selected as the material of the conductor sphere 1 instead of aluminum.

  The magnet fixing base 7 is a member on a flat plate for fixing a permanent magnet that generates a rotating magnetic field. The magnet fixing base 7 is disposed so as to be parallel to the surface of the sample 100 placed in the sample container 2 (the liquid level if the sample 100 is liquid). Moreover, the magnet fixing base 7 is provided so as to rotate in the horizontal direction. Specifically, the magnet fixing base 7 is attached to the motor 4 via the motor shaft 4a. When the magnet fixing base 7 rotates, the plane formed by the upper surfaces of the permanent magnets fixed to the magnet fixing base 7 is parallel to the upper surface (liquid level) of the sample filled in the sample container 2, that is, A magnet fixing base 7 is attached to the motor 4 so as to be a horizontal plane.

  A plurality of permanent magnets are arranged on the upper surface of the magnet fixing base 7 along the periphery of the magnet fixing base 7. The permanent magnets are arranged so that the N pole and the S pole are vertically positioned in the thickness direction of the sample fixing base 7. Further, when the magnet fixing base 7 is viewed from the upper surface side, a plurality of adjacent permanent magnets are alternately arranged so that the N pole and the S pole are alternately the upper surface (surface on the sample container 2 side). ing. That is, since the N poles and S poles of the adjacent permanent magnets are alternately arranged on the upper surface, 2n pieces are arranged. In the present embodiment, for example, four permanent magnets, that is, each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 are fixed to the upper surface of the magnet fixing base 7. The number of magnets is not limited to four, and may be an even number such as two, six, eight, or 2n, and 2n of n sets of magnets having N and S poles on the upper surface are represented by N The poles and the S poles may be arranged alternately.

FIG. 4 is a diagram illustrating an arrangement example of magnets on the magnet fixing base 7 as viewed from above.
In the example shown in FIG. 4A, the first magnet 31 is disposed so that the S pole is in contact with the upper surface of the magnet fixing base 7 and the surface located on the sample container 2 side is the N pole.
The second magnet 32 is arranged so that the N pole is in contact with the upper surface of the magnet fixing base 7 and the surface located on the sample container 2 side is the S pole.
The third magnet 33 is arranged so that the N pole is in contact with the upper surface of the magnet fixing base 7 and the surface located on the sample container 2 side is the S pole.
The fourth magnet 34 is arranged so that the S pole is in contact with the upper surface of the magnet fixing base 7 and the surface located on the sample container 2 side is the N pole.

Therefore, each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 is disposed such that poles having different polarities are located on the sample container 2 side.
Further, the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 are alternately arranged symmetrically with respect to the rotation axis of the magnet fixing base 7.

  In the present embodiment, the magnetic flux density in the vicinity of the surfaces of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 (near the surface facing the sample container 2) is 0.3T. (Tesla). Each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 is a permanent magnet having a size of 10 mm in length, 10 mm in width, and 5 mm in height.

Next, FIG. 4A is a diagram illustrating the arrangement relationship of each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 in the magnet fixing base 7 as viewed from above.
FIG. 4A shows the arrangement of magnets in plan view in the present embodiment. Each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 is square in a plan view, and the magnetic poles on the upper surface of the magnet are arranged so that the north and south poles are alternately arranged. ing.

  FIG. 4B shows the arrangement of magnets in the modification of FIG. In this modification, the case where each of the 5 magnets 35 and the 6th magnets 36 which are two magnets arrange | positioned is a rectangle is shown. Also in the case of FIG. 4B, each of the fifth magnet 35 and the sixth magnet 36 is such that the magnetic poles on the upper surface of the permanent magnet fixed to the magnet fixing base 7 are alternately N and S poles. Is arranged.

  Although not shown in the drawing, a plurality of (N, N = 2n, n is an integer of n ≧ 1) small magnets are positioned at positions corresponding to the circulation path 23 in the sample container 2, and the magnetic poles on the upper surface of the magnet are N The poles and the S poles may be arranged alternately. In addition, the magnet fixing base 7 may be arranged on the upper part of the sample container 2. That is, it is good also as a structure which arrange | positions the magnet fixing stand 7 so that the upper surface of a permanent magnet may become horizontal above the liquid level of the sample 100 with which the sample container 2 was filled.

Returning to FIG. 1, the rotating magnetic field formed by the permanent magnet will be described. Regarding the magnetic field (rotating magnetic field) by N magnets in which N permanent magnets are arranged at intervals of 2π / N, each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 is used. When the magnetic flux density is B ₀ , the declination direction component B _θ and the vertical direction component B _z are ideally expressed by the following equations (1) and (2). Equations (1) and (2) are declination (that is, an angle at an arbitrary point in the circulation path 23) θ, time t, driving angular velocity ω (ω = 2πf, f: driving frequency, angular velocity in rotation of the rotating magnetic field). It is expressed using N is the number of magnet pairs in which the magnetic poles on the upper surface are the N pole and the S pole.
B _z = B ₀ · cos (ωt−nθ) (1)
B _θ = B ₀ · sin (ωt−nθ) (2)

In the above-described equations (1) and (2), it is assumed that each of the declination direction component B _θ and the vertical direction component B _z is represented. That is, the magnetic field has a constant strength, and the torque applied to the conductor sphere 1 from the rotating magnetic field is calculated on the assumption that the moving direction performs a uniform circular motion. This rotating magnetic field is generated by the magnetic flux density generated in the space by the first magnet 31, the second magnet 32, the third magnet 33 and the fourth magnet 34 when the magnet fixing base 7 is rotated by the motor 4. Further, the rotating direction of the rotating magnetic field viewed from the center of the circulation path is opposite to the rotating direction of the magnet when the upper surface of the magnet fixing base 7 (the surface on which the magnet is fixed) is viewed from above, that is, the rotating direction of the motor 4. And in the opposite direction.
For example, when the rotation direction of the magnet fixing base 7 is clockwise when viewed from above vertically, the rotation direction of the rotating magnetic field is counterclockwise when viewed from the center of the rotation path of the rotor.
Further, the rotating magnetic field applies substantially the same (equivalent) magnetic field to the conductor sphere 1 at any position on the circuit path 23. Along with the progress of the rotating magnetic field on the circular path 23, the magnetic field rotates in a vertical plane including a tangent on the circumference in plan view of the circular path 23 at each position of the traveling magnetic field.

Here, even if the rotating direction of the rotating magnetic field is not a constant velocity circular motion, for example, an elliptical motion, a torque for moving along the circulation path 23 of the sample container 2 is applied to the conductor sphere 1. Can do.
Although details will be described later, the magnitude of the torque acting on the conductor sphere 1 or the evaluation of the viscosity can be obtained by calibrating the revolution speed of the conductor sphere with a sample having a known viscosity.
The distance from the magnet surfaces of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 to the bottom 24 of the sample container 2 is selected to be applied to the conductor sphere 1 in the circulation path 23. It is possible to approximate the rotating magnetic field to be more approximate to the above-described equations (1) and (2).

Next, the sample stage 6 is a member on a flat plate for fixing the sample container 2 into which the sample 100 is placed. The sample table 6 is arranged so that the upper surface thereof is parallel to the upper surface of the magnet fixing table 7.
Thereby, when the upper surface of the bottom 24 of the sample container 2 and each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 rotate, the first magnet 31, the second magnet 32, The planes formed by the upper surfaces of the third magnet 33 and the fourth magnet 34 are parallel to each other.
From the arrangement of the sample stage 6, the magnet fixing stage 7, the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 described above, the first magnet 31, the second magnet 32, and the third magnet 33 are arranged. The fourth magnet 34 can generate a magnetic field perpendicular to the top surface of the bottom 24 of the sample container 2 on which the conductor sphere 1 is disposed. Further, a magnetic field in the horizontal direction can be generated with respect to the upper surface of the bottom 24.

The motor 4 is a drive mechanism that rotates the magnet fixing base 7 in a rotation direction parallel to the surface of the magnet fixing base 7. In the motor 4, the motor shaft 4 a is fixed so that the axial direction is perpendicular to the upper surface of the magnet fixing base 7. For example, in the present embodiment, the motor 4 can arbitrarily set the number of rotations from 50 to 4000 revolutions per minute.
Further, the arrangement of the motor shaft 4 a, the sample container 2, and the motor 4 is set so that the conductor ball 1 circulates around the circulation path 23 in the bottom 24 of the sample container 2 in plan view. That is, the sample container 2 and the motor 4 are arranged so that the center of the sample container 2 and the motor shaft 4a overlap in plan view.

  FIG. 5 shows the magnet fixing base 7 in the present embodiment, the first magnet 31, the second magnet 32, the third magnet 33 and the fourth magnet 34 arranged on the magnet fixing base 7, and the circulation path 23 in the sample container 2. FIG. A white arrow W in FIG. 5 represents a magnetic field vector composed of the magnitude and direction of the magnetic field on the reference plane.

The rotation detection sensor 5 is arranged in the upper direction of the sample container 2 at a position where the conductor sphere 1 sinking in the sample 100 of the sample container 2 can be detected. The rotation detection sensor 5 optically detects the position of the conductor sphere 1. That is, the rotation detection sensor 5 emits laser light from the light irradiating unit, makes reflected light from the upper surface of the conductor sphere 1 enter the light receiving unit, and outputs a detection electric signal corresponding to the intensity of the incident light.
Further, instead of the rotation detection sensor 5, an imaging device in which an imaging device such as a lens and a CCD (Charge Coupled Device) is added to a microscope is provided, and a captured image obtained by enlarging the moving state of the conductor ball 1 in the circuit path 23. , And the rotational speed may be detected from the image processing. In this case, the number of laps around the circuit path 23 is detected, and the number of laps is set to 1 when the circuit circulates the circuit path 23 once.
Furthermore, it is good also as a structure which arrange | positions an electrostatic capacitance sensor in the lower part of the bottom part 24 of the sample container 2 in the position which overlaps with the circulation path | route 23 by planar view, and calculates | requires the frequency | count of passing this electrostatic capacitance sensor as a rotation speed.

Here, by rotating the magnet fixing base 7 with the motor 4, each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 rotates, and a rotating magnetic field as a magnetic field that varies with time. Is formed in the space on the upper surface side of the magnet fixing base 7. Torque is applied to the conductor sphere 1 by this rotating magnetic field, and the conductor sphere 1 is rolled along the circular path 23 in which the sample 100 in the sample container 2 is accumulated, and is caused to move at a constant speed. Then, the viscosity of the sample is measured from the moving speed of the conductor sphere 1 in the sample 100.
A method for measuring the viscosity of the sample from the moving speed of the conductive ball 1 in the sample 100 will be described below.

The viscosity measurement unit 8 includes a rotation detection unit 81, a viscosity detection unit 82, a rotating magnetic field control unit 83, a standard data storage unit 84, and a device control unit 85.
The rotation detection unit 81 detects the conductor sphere 1 based on the detection electric signal supplied from the rotation detection sensor 5. The rotation detection unit 81 obtains and outputs the revolution angular velocity Ω _s by using the number of detections per unit time (for example, 1 second) as the number of rotations per unit time (rpm: revolutions per minute). Further, the rotation detection unit 81 can also use a captured image of the imaging device instead of using the electric signal detected by the rotation detection sensor 5 in detecting the conductor sphere 1. When the conductor sphere 1 is detected using the captured image of the imaging device, the conductor sphere 1 is detected by image processing from the captured image that is captured and output by the imaging device, and the revolution angular velocity Ω _s is set as the number of rotations per unit time. You may make it ask.

  The rotating magnetic field control unit 83 performs rotation control on the motor 4 so that the motor 4 rotates at the set number of rotations. As a result, the magnet fixing base 7 rotates at a predetermined rotational speed via the motor shaft 4a, and the magnetic fields generated by the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 rotate. . In this way, a rotating magnetic field is generated that rotates the conductor sphere 1 in the circular path 23 by a uniform circular motion.

The standard data storage unit 84 stores a viscosity detection table indicating the relationship between the ratio of the rotation speed of the motor 4 to the rotation speed of the conductor ball 1 immersed in a standard sample whose viscosity is known and the viscosity (cP). Has been.
This viscosity detection table is created as follows. In the viscosity measuring apparatus of this embodiment, a standard sample whose viscosity is known in advance is filled in the sample container 2 and the conductor sphere 1 is immersed in the standard sample. The case of rotating the motor 4 by a plurality of rotational speed Omega _M set in advance, the revolution angular velocity Omega _s conductor sphere 1 corresponding to the rotational speed Omega _M of each motor 4 is measured by the rotation detecting unit 81 described above. The revolution angular velocity Ω _s for the standard sample is measured for a standard sample having a plurality of different viscosities. The standard sample is a sample whose viscosity is known in advance.

Next, FIG. 6 is a graph showing the correspondence between the amount related to torque in a plurality of standard samples having different viscosities and the revolution angular velocity Ω _s of the conductor ball 1.
Here, the quantity related to the torque is “nΩ _M + (1−R / r) · Ω _s ”. The angular frequency nΩ _M of the rotating magnetic field and the revolution angular velocity Ω _s of the conductor sphere 1 are obtained by adding the result of (1−R / r). Here, R is the radius of the circular orbit of revolution of the conductor sphere 1, that is, the radius of the circular circulation path 23. R is the radius of the conductor sphere 1. Here, as shown in FIG. 2B, the radius R is the distance between the center position Q between the inner diameter side wall and the outer diameter side wall of the circulation path 23 and the center P of the circulation path 23. Here, n is the number of S poles and N poles of the magnet as already described, and n = 1 in the measurement of FIG.

In the graph shown in FIG. 6, the viscosities of the standard samples used are different. For example, the sample of the series 1 is 1 mPa · s, the sample of the series 2 is 2 mPa · s, and the sample of the series 3 is 5 mPa · s. Then, since n = 1, the amount “Ω _M + (1−R / r) · Ω _s ” related to the torque of each standard sample having different viscosities and the revolution angular velocity Ω _s of the conductor sphere 1 are obtained from FIG. A straight line indicating the relationship, that is, the correspondence of the slope “(Ω _M + (1−R / r) · Ω _s ) / Ω _s ” is obtained by the least square method or the like. This slope is proportional to the viscosity.

Next, FIG. 7 shows the correspondence between the viscosity (mPa · s) and the slope “(Ω _M + (1−R / r) · Ω _s ) / Ω _s ” for each standard sample having different viscosities. It is a graph.
The standard data storage unit 84 illustrated in FIG. 1 stores a viscosity detection table indicating the correspondence between the viscosity and the inclination “(Ω _M + (1−R / r) · Ω _s ) / Ω _s ”. In addition, instead of the viscosity detection table, an empirical formula indicating the correspondence between the viscosity and the inclination “(Ω _M + (1−R / r) · Ω _s ) / Ω _s ” may be stored.

Viscosity detector 82, to the rotating magnetic field control unit 83 performs control for rotating the motor 4 in a plurality of different angular frequencies Omega _M. The viscosity detector 82 outputs a control signal to the rotation detector 81 every time the rotation speed is changed.
Each time the control signal is supplied from the viscosity detector 82, the rotation detector 81 receives the revolution angular velocity Ω _s in the circulation path 23 of the conductor ball 1 submerged in the sample 100 placed in the sample container 2 at the angular frequency Ω _M. Is input from the rotation detection sensor 5.
Then, the rotation detector 81 outputs the detected revolution angular velocity Ω _s to the viscosity detector 82 corresponding to the control signal.

As in the case of the standard sample described above, the viscosity detection unit 82 determines the inclination of the revolution angular velocity Ω _s of the conductor sphere 1 and “Ω _M + (1−R / r) · Ω _s ” with respect to the sample 100. The slope “(Ω _M + (1−R / r) · Ω _s ) / Ω _s ” is calculated.
Then, the viscosity detection unit 82 reads “(Ω _M + (1−R / r) · Ω _s ) / Ω _s ” of the sample 100 from the viscosity detection table written and stored in advance in the standard data storage unit 84. The viscosity η (mPa · s) corresponding to is read, and this is output as the viscosity η of the sample 100.
When the empirical formula is stored in advance in the standard data storage unit 84, the viscosity detection unit 82 reads out the empirical formula from the standard data storage unit 84, and the gradient “(Ω _M + (1− R / r) · Ω _s ) / Ω _s ”is substituted and the viscosity is calculated.

  Next, a method of applying a rotational torque to the conductor sphere 1 and rolling the conductor sphere 1 along the circulation path 23 to make a circular motion will be described with reference to FIG. FIG. 8 shows a method of applying a rotational torque to the conductor sphere 1 by a rotating magnetic field generated by the rotation of four magnets of the first magnet 31, the second magnet 32, the third magnet 33 and the fourth magnet 34. FIG.

  As shown in FIG. 5, the N pole of the first magnet 31, the S pole of the second magnet 32, the S pole of the third magnet 33, and the N pole of the fourth magnet 34 are in relation to the circuit path 23. When arranged on the magnet fixing base 7, a magnetic field perpendicular to a certain reference plane is generated. Here, the upper surface of the sample 100 passing through the center of the rotor placed in the sample container 2 and the surface parallel to the liquid surface when the sample 100 is liquid are used as the reference surface. This reference plane is a reference two-dimensional plane (the liquid level of the sample 100) composed of the x-axis and the y-axis, and the rotation axis of the conductor sphere 1 that moves around the circuit path 23 in the sample 100 is the z-axis.

  FIG. 8 shows the magnetic field generated by the magnet on the circulation path 23 from the center of the circulation path 23 shown in FIG. Here, the declination angle θ takes one point on the circuit path 23, and this one point and the z axis are the rotation axes, and the x axis in the two-dimensional coordinate system composed of the x axis and the y axis is counterclockwise. The rotation angle of the conductor sphere 1 is shown. Therefore, the declination θ increases from 0 to 2π [radian], and goes around the circulation path 23 by 2π.

  That is, when the conductive ball 1 circulates in the counterclockwise direction along the circulation path 23 in FIG. 5, it passes through the first magnet 31, the second magnet 32, the fourth magnet 34, and the third magnet 33 in this order. At this time, the area where the first magnet 31 is disposed is the deflection angle θ from 0 to π / 2. A region where the second magnet 32 is disposed is the deflection angle θ from π / 2 to π. An area where the fourth magnet 34 is arranged is that the deflection angle θ is from π to 3π / 2. A region where the third magnet 33 is disposed is when the deflection angle θ ranges from 3π / 2 to 2π.

In FIG. 8, the z-axis is a vertical direction of a plane formed by the surfaces of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34 (a two-dimensional plane formed of the x-axis and the y-axis). Is a coordinate axis parallel to. A white arrow W in FIG. 8 represents a magnetic field vector composed of the magnitude and direction of the magnetic field on the reference plane.
Here, when the magnet fixing base 7 is rotated clockwise (in the direction of arrow A in FIG. 5) by the motor 4, each of the first magnet 31, the second magnet 32, the fourth magnet 34, and the third magnet 33 is also Rotate clockwise. In FIG. 8, each of the first magnet 31, the second magnet 32, the fourth magnet 34, and the third magnet 33 moves from 0 toward 2π, that is, toward the right in the figure.

At this time, the magnetic field at an arbitrary point in the circulation path 23, that is, the magnetic field applied to the conductor sphere 1 becomes a rotating magnetic field with the counterclockwise direction as the rotation direction.
As a result, an induced current is induced on the surface of the conductor sphere 1 due to the fluctuation of the magnetic field due to the rotating magnetic field. For this reason, torque is generated in the conductor sphere 1 due to Lorentz interaction between the induced current generated on the surface and the rotating magnetic field. Since torque due to this Lorentz interaction is generated in the same direction as the rotating magnetic field, the conductor sphere 1 rotates counterclockwise following the rotating direction of the rotating magnetic field. That is, the conductor ball 1 circulates in the circulation path 23 in the direction opposite to the clockwise direction that is the rotation direction of each of the first magnet 31, the second magnet 32, the third magnet 33, and the fourth magnet 34.

The magnitude T of torque due to this Lorentz interaction can be expressed by the following equation (3).
T = (2π / 15) · n · σ · r ⁵ · B ² · Ω _M (3)
In this equation (3), the radius of the conductor sphere 1 is r, the magnitude of the rotating magnetic field (magnetic flux density) is B, the angular frequency of rotation of the rotating magnetic field is n · Ω _M, and the material constituting the conductor sphere 1 Let σ be the electrical conductivity of.

As described above, in FIG. 5, when each of the first magnet 31, the second magnet 32, the fourth magnet 34, and the third magnet 33 rotates clockwise (in the direction of the arrow A), A torque that rotates counterclockwise along the path 23 is applied.
At this time, the conductor ball 1 is in contact with the sample container 2 at the bottom of the circulation path 23 when it circulates around the circulation path 23. For this reason, the conductor ball 1 circulates around the circulation path 23 while rotating (spinning) counterclockwise by the torque.
In the sample container 2, a circular path 23, which is a circular orbit centering on the center of the container, is formed as a groove. For this reason, when the conductor ball 1 circulates around the rotation center of the magnet fixing base 7, a circular motion that moves while rolling on the circulation path 23 by the applied torque is performed.

Here, the torque applied to the conductor sphere 1 when the conductor sphere 1 circulates around the circulation path 23 will be considered. For example, if the conductor ball 1 is fixed, in proportion to the angular velocity Omega _M of rotation of the rotating magnetic field, torque shown in the above (3) is applied to the conductor sphere 1.
Then, the conductive ball 1 starts a revolving motion that revolves along the revolving path 23 by the torque applied by the rotating magnetic field, and reaches a steady state with respect to the applied torque. The angular velocity of the rotational motion around the conductor sphere 1 in this steady state is defined as Ω _s . At this time, the rotational angular velocity of the rotating magnetic field felt at the center of the conductor sphere 1 is nΩ _M + Ω _s . That is, as shown in FIG. 4A or FIG. 8, when the number of N poles and S poles is 2, and n = 2, the rotational angular velocity of the rotating magnetic field felt at the center of the conductor sphere 1 Is 2Ω _M + Ω _s . Also, as shown in FIG. 4B, when the number of N poles and S poles is 1, and n = 1, the rotational angular velocity of the rotating magnetic field felt at the center of the conductor sphere 1 is Ω _M + Ω _s .

On the other hand, when the conductor sphere 1 circulates along the circulation path 23, it can be considered that the conductor sphere 1 is rotated by the rotation of the rotating magnetic field.
The rotation angular velocity Ω _R that is the rotation angular velocity can be expressed by the following equation (4), where r is the radius of the conductor sphere 1 and _R is the radius of the revolution circular orbit (circular path 23).
Ω _R = (R / r) · Ω _s (4)

When the conductor sphere 1 is in a steady state with respect to the applied torque, the angular velocity Ω _st proportional to the torque applied to the conductor sphere 1 can be expressed by the following equation (5).
Ω _st = nΩ _M + Ω _s − (R / r) · Ω _s = nΩ _M + (1− (R / r)) · Ω _s (5)

Next, a method for obtaining the viscosity from the angular velocity in the circular motion of the conductor sphere 1 will be described.
When the conductor sphere 1 is present in the sample 100 that is a viscous fluid, the moving speed in the sample 100 is inversely proportional to the viscosity of the sample 100 at a constant applied torque.
That is, the relationship between the angular velocity _Ωst and the viscosity of the conductor sphere 1 in the steady state can be expressed by the following equation (6).
Ω _st = nΩ _M + (1- (R / r)) · Ω _s = A · η · Ω _s (6)
In this equation (6), the viscosity is η and the constant is A.
Therefore, in the viscosity detection table stored in the standard data storage unit 84, “(nΩ _M + (1− (R / r)) · Ω _s ) / Ω _s ” and viscosity η (mPa · s) Response can be sought.

  As already mentioned, it is assumed that the rotating magnetic field is in a plane perpendicular to the reference two-dimensional plane and does not depend on the z-axis. However, there is no problem in the following explanation even if it depends on the z-axis. In addition, if there is a magnetic field component that rotates in a plane perpendicular to the reference two-dimensional plane, it rotates relative to the conductor sphere 1 even if there are other magnetic field components that are not perpendicular to the reference two-dimensional plane. Does not hinder the application of torque.

FIG. 9 is a diagram showing an electromagnet. The electromagnet shown in FIG. 9 is configured by arranging a yoke 10 and teeth 10a, 10b, 10c, and 10d protruding from the yoke 10 on a reference two-dimensional plane. A winding CL1 is wound around each of the teeth 10a and 10c in different winding directions. Similarly, the windings CL2 are wound around the teeth 10b and 10d in different winding directions.
Instead of generating a rotating magnetic field from the magnetic fields radiated by the first magnet 31, the second magnet 32, the third magnet 33 and the fourth magnet 34, which are permanent magnets, by rotating the magnet fixing base 7 with the motor 4 in FIG. You may generate | occur | produce a rotating magnetic field using the structure of the electromagnet of FIG. 9 mentioned above.

That is, a current is passed through the windings CL1 and CL2 to generate a magnetic field perpendicular to the reference two-dimensional plane. Then, the direction of the current flowing through the windings CL1 and CL2 may be periodically changed to rotate the magnetic field perpendicular to the reference two-dimensional plane to form a rotating magnetic field. That is, each electromagnet is driven so that each electromagnet arranged on the circumference has a different polarity from other adjacent electromagnets. When the electromagnet is driven, the rotating magnetic field may be generated by changing the polarity of each electromagnet every time.
In this case, the rotating magnetic field control unit 83 applies a current to the windings CL1 and CL2 in the electromagnet of FIG. 9, and periodically changes the direction of the flowing current to generate a rotating magnetic field.
With this rotating magnetic field, as in the case where a magnet is already used, a circular motion that circulates the conductor sphere 1 along the circulation path 23 is performed in the sample 100 to determine the viscosity of the sample 100.

In addition, as described above, the number of rotations (rotational angular velocity) of the conductor sphere 1 is observed by detecting the circulation of the conductor sphere 1 in the circulation path 23 using an image sensor such as an optical sensor or a CCD. .
However, the upper surface of the conductor sphere 1 may be configured to irradiate a laser and optically measure the reflection and interference pattern changes due to rotation.
Further, a part of the conductor sphere 1 is replaced with a dielectric, and the electrode in which the conductor sphere 1 is sandwiched between the electrodes is arranged at a position that does not interfere with the rotation of the magnet fixing base 7 as shown in FIG. Also good. Then, when the dielectric as a mark passes between the electrodes, the rotation detection unit 81 detects a change in the capacitance of the capacitor formed by the electrodes, and detects the number of changes in the capacitance during a predetermined period (for example, 1 second). Then, the rotational speed of the conductive ball 1 may be detected and the rotational angular velocity may be obtained. As described above, the rotation detection unit 81 may obtain the rotation angular velocity by electrical measurement.

Further, the rotating magnetic field control unit 83 may arbitrarily change the rotation period and the rotating direction of the rotating magnetic field to be applied to the conductor sphere 1.
For example, by periodically sweeping the rotation direction and the rotation speed of the rotating magnetic field, a periodically changing rotational torque can be applied to the conductor sphere 1.

Next, a specific application example in the viscosity measuring apparatus (mechanical property measuring apparatus) shown in FIG. 1 will be described.
Three standard viscosity liquids of 1 mPa · s, 2 mPa · s, and 5 mPa · s were used as the standard samples whose viscosity was known in advance by the viscosity measuring apparatus according to the present embodiment.
And the result of having measured the angular velocity (omega | ohm) _s in the revolution of the conductor sphere 1 is shown in FIG. 6, changing the angular velocity (omega) _M of a rotating magnetic field. In this measurement, the number of N poles and S poles of the magnet is 1 respectively, that is, the configuration of FIG. 4B, and n = 1. As described above, FIG. 6 shows the amount “Ω _M + (1− (R / r)) · Ω _s ” proportional to the torque as the vertical axis and the amount “angular velocity Ω proportional to the rotational speed of the conductor sphere 1. It is the graph which plotted the measurement result of the standard sample on the horizontal axis of “ _s ”. Further, as already described, this slope “(Ω _M + (1− (R / r)) · Ω _s ) / Ω _s ” is an amount proportional to the viscosity η.

In the proportional relationship between the slope “(Ω _M + (1− (R / r)) · Ω _s ) / Ω _s ” and the viscosity η, the Reynolds number increases as a result of the influence of the nonlinear term in the Navier-Stokes equation, that is, As the angular velocity Ω _s increases, the deviation from the straight line increases.
Therefore, in a low-viscosity sample with a large Reynolds number, the proportional relationship between “(Ω _M + (1− (R / r)) · Ω _s ) / Ω _s ” and viscosity η is based on an approximation of a linear function. Shift.

For this reason, in this embodiment, in the relationship between “(Ω _M + (1− (R / r)) · Ω _s ) / Ω _s ” and viscosity η shown in FIG. 6, x = Ω _s and y = Data obtained as Ω _M + (1− (R / r)) · Ω _s was approximated by the following equation (7).
y = a · x + b · x ² (7)
In the equation (7), a and b are coefficients of x and x ² in polynomials that are approximate equations shown in FIG.

Then, the equation (7) is differentiated to obtain the following equation (8).
y ′ = a + 2b · x (8)
In this equation (8), the coefficient a at b = 0, that is, the angular velocity Ω _s = 0, and the viscosity are plotted in correspondence with each other, and the graph shown in FIG. 7 is created. That is, the coefficient of the first-order term in the polynomial is approximated as the slope of the polynomial.
From FIG. 7, even in a low-viscosity region of 10 mPa · s or less (6 mPa · s or less in the figure), the viscosity is “(Ω _M + (1− (R / r)) · Ω _s ) / Ω _s ”. It can be seen that the function indicating the relationship with η is a linear function of a straight line, and the straight line passes through the origin, and viscosity measurement having sufficient resolution is realized.

Therefore, also when measuring the viscosity of the sample 100, the viscosity detecting unit 82 changes the angular velocity Ω _s through the rotating magnetic field control unit 83 in the same manner as when measuring the standard sample, and as shown in FIG. (Ω _M + (1− (R / r)) · Ω _s ”and“ Ω _s ”are measured for each predetermined angular velocity Ω _s .

Next, the viscosity detector 82 obtains a polynomial corresponding to “(Ω _M + (1− (R / r)) · Ω _s ” and “Ω” measured for each angular velocity Ω _s .
Then, the viscosity detector 82 obtains the coefficient a of the first-order term of the obtained polynomial. The viscosity η corresponding to the coefficient a is read from the viscosity detection table stored in the standard data storage unit 83 and output as a measured value of the viscosity η of the sample 100.

  In addition, a program for realizing the function of the viscosity measuring unit 8 in FIG. 1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into the computer system and executed to execute the viscosity. Measurement processing may be performed. Here, the “computer system” includes hardware such as an OS (Operating System) and peripheral devices.

Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW (World Wide Web) system is used.
The “computer-readable recording medium” refers to a storage device such as a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a hard disk built in the computer system. Further, the “computer-readable recording medium” is a memory that dynamically holds a program for a short time, like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. Includes media. Further, a storage medium that holds a program for a certain period of time, such as a volatile memory inside a computer system serving as a server or a client in that case, is also included. The program may be a program for realizing a part of the functions described above. Further, the program may be a program that can realize the above-described functions in combination with a program already recorded in the computer system.

  As mentioned above, although embodiment of this invention has been explained in full detail with reference to drawings, the concrete structure is not restricted to the said embodiment, The design etc. of the range which does not deviate from the summary of this invention are included.

  According to the above, the amount of the sample which is the substance to be measured is smaller than the conventional one, the apparatus can be downsized compared to the conventional one, and the viscosity of the low viscosity substance of about 10 cP or less is compared with the conventional one. Thus, it is possible to provide a viscosity measuring apparatus and method capable of measuring with high accuracy.

DESCRIPTION OF SYMBOLS 1 ... Conductive ball 2 ... Sample container 31 ... 1st magnet 32 ... 2nd magnet 33 ... 3rd magnet 34 ... 4th magnet 35 ... 5th magnet 36 ... 6th magnet 4 ... Motor 4a ... Motor shaft 5 ... Rotation detection sensor 6 ... Sample stand 7 ... Magnet fixing stand 8 ... Viscosity measuring unit 21, 22 ... Side wall 23 ... Circuit path 24 ... Bottom part 81 ... Rotation detecting unit 82 ... Viscosity detecting unit 83 ... Rotating magnetic field control unit 84 ... Standard data storage unit 85 ... Device control unit 100 ... Sample 500 ... Cylinder

Claims (17)

A container containing a substance to be measured whose viscosity is to be detected;
A spherical rotor formed of a conductive material, settling in the substance to be measured and arranged in contact with the bottom of the container;
A magnet for applying a magnetic field to the rotor;
Applying a rotating magnetic field to the rotor by the magnet, inducing an induced current in the rotor, and applying a rotational torque to the rotor by Lorentz interaction between the induced current and the magnetic field applied to the rotor; A rotating magnetic field control unit for controlling the magnetic field so as to cause the rotor to make a circular motion by corresponding to the rotation of the rotating magnetic field;
A viscosity measuring device comprising: a viscosity detector that detects the viscosity of the substance to be measured based on the number of times of circular motion of the rotor.   The viscosity measuring apparatus according to claim 1, wherein the circular motion is a circular motion in which the rotor rolls on a bottom portion of the container.   The said container has a circular circular path | route comprised as a groove | channel at the bottom part of the area | region filled with the said measuring object substance, The said rotor performs circular motion along the said circular path | route. Viscosity measuring device.   The viscosity measuring device according to claim 3, wherein the circulation path is configured by a groove surrounded by outer and inner side walls provided with respect to the bottom of the container. The vertical component B _z of the magnetic field on the circuit path received by the rotor and the component B _θ along the circuit path are ω is the angular velocity of the rotating magnetic field, B ₀ is the magnetic field of the magnet, and θ is the circuit 5. The magnetic field according to claim 1, wherein the magnetic field is a magnetic field represented by the following formula, where t is a time and n is a natural number: Viscosity measuring device.
B _z = B ₀ · cos (ωt−nθ) (1) Formula B _θ = B ₀ · sin (ωt−nθ) (2) Formula   The rotating magnetic field applies an equivalent magnetic field to the rotor at any position of the circuit path, and the direction of the magnetic field at each position that travels with the progress of the magnetic field on the circuit path is the circuit. The viscosity measuring device according to any one of claims 3 to 5, wherein the viscosity measuring device rotates in a vertical plane including a tangent on a circumference in a plan view of the path.   The viscosity measuring device according to any one of claims 3 to 6, wherein a position of the bottom portion of the container serving as a circulation path of the rotor is a horizontal plane. The rotating magnetic field control unit
A rotating magnetic field to be applied to the rotor by rotating a magnet fixing base on which a plurality of permanent magnets are arranged so that N poles and S poles alternately become upper surfaces on a plane perpendicular to the rotation axis of the rotating magnetic field. The viscosity measuring device according to any one of claims 1 to 7, wherein   The said magnet is comprised from the permanent magnet, It rotates in parallel with respect to the said arrangement | positioning surface centering | focusing on the said rotating shaft, The said rotating magnetic field applied to the said rotor is produced | generated. Viscosity measuring device. The magnet is composed of an electromagnet;
The rotating magnetic field control unit generates the rotating magnetic field by driving the electromagnet so as to change the polarity every time so that the arranged electromagnets have different polarities from other adjacent electromagnets. The viscosity measuring device according to any one of claims 1 to 7.   The viscosity measuring device according to claim 7 or 8, wherein the magnet is disposed in an upper part or a lower part of the container in parallel to the surface of the substance to be measured. A rotation detector for measuring the number of laps of the rotor;
The viscosity measuring device according to any one of claims 1 to 11, wherein the viscosity detecting unit obtains the viscosity of the measurement target substance based on a relationship between the number of rotations of the rotating magnetic field and the number of rotations of the rotor. . There is further provided a standard data storage unit for previously storing, as standard data, the number of rotations of the rotor in a plurality of reference materials whose viscosities are known in advance, the number of rotations of the rotating magnetic field, and the viscosity of the reference material. And
13. The viscosity of the measurement target material is obtained by comparing the rotation number of the rotor and the rotation number of the rotating magnetic field in the measurement target material measured by the viscosity detection unit with the standard data. The viscosity measuring device according to any one of the above.   The viscosity measurement device according to claim 12, wherein the rotation detection unit detects the number of rotations of the rotor by optical measurement.   The viscosity measuring apparatus according to claim 12, wherein the rotation detection unit detects the number of rotations of the rotor by electrical measurement.   The viscosity measuring device according to any one of claims 1 to 15, wherein the measurement target substance is a liquid or a soft material. In a container containing a measurement target substance whose viscosity is to be detected, a spherical rotor formed of a conductive material, submerged in the measurement target substance, and arranged in contact with the bottom of the container In contrast, the process of applying a magnetic field with a magnet,
A rotating magnetic field is applied to the rotor by the magnet, an induced current is induced in the rotor, and a rotational torque is applied to the rotor by Lorentz interaction between the induced current and a magnetic field applied to the rotor, A process of rotating the rotor in response to the rotation of the rotating magnetic field;
A method of detecting the viscosity of the substance to be measured based on the number of rounds of the circular motion of the rotor.

Images