JP7054139B2 - Viscoelasticity measuring device and viscoelasticity measuring method - Google Patents

Description

The present invention relates to a viscoelasticity measuring device and a viscoelasticity measuring method for measuring the viscoelasticity of a measurement object having viscoelasticity such as food.

In order to realize an appropriate texture of food, it is necessary to evaluate the viscoelastic property of the food. Conventionally, various devices and methods for evaluating the viscoelasticity of foods have been proposed. For example, a measuring device and a measuring method as disclosed in Patent Document 1 below have been proposed. This measuring device and measuring method are an exploration system that measures viscoelastic properties while pressing and abutting against the measurement target site, and signal processing for processing signals obtained from the exploration system to measure viscoelastic properties. It consists of a system.

Japanese Unexamined Patent Publication No. 2007-24606

However, conventionally, since the exploration system is pressed against the measurement target portion, the characteristics of the measurement target portion after pressing may change. For example, the measurement target portion after pressing is hardened as compared with the measurement target portion before pressing. In this case, if the measurement is performed a plurality of times, the original viscoelasticity of the measurement target portion cannot be obtained in the second and subsequent measurements. Further, since the exploration system is pressed against the measurement target portion, the measurement target portion may be damaged or destroyed. Especially when the measurement target part is food, if it is destroyed at the time of measurement, the measurement cannot be performed during cooking. Further, when the measurement target part is particularly food, the exploration system comes into contact with the measurement target part in addition to the dish on which the measurement target part is placed, which poses a hygiene problem.

The present invention has been made in view of such circumstances, and its main purpose is a viscoelasticity measuring device capable of accurately quantifying the viscoelasticity of a measurement object without pressing the measurement object. And to provide a viscoelasticity measuring method.

The viscoelasticity measuring device according to the present invention for achieving the above object has a vibrating table on which a measuring object is placed, and a vibrating means for vibrating the shaking table and the measuring object are placed on the shaking table. A displacement detecting means for detecting a first displacement, which is a displacement of a predetermined point of the object to be measured, and a second displacement, which is a displacement of a predetermined point of the shaking table, while the shaking table is vibrated. The first sine wave, which is a sine wave indicating the time change of the first displacement detected by the displacement detecting means, and the second sine wave, which is a sine wave indicating the time change of the second displacement detected by the displacement detecting means. The ratio of the amplitude of the first sine wave to the amplitude of the second sine wave based on the sine wave generating means for generating a wave and the first sine wave and the second sine wave generated by the sine wave generating means. A response magnification indicating the above, a calculation means for obtaining the phase difference between the first sine wave and the second sine wave, and a linear spring on the wall body on which the object placed on the base is erected on the base. In the formula showing the Young rate of the measurement object obtained by approximating the vibration of the measurement object to the vibration model that vibrates the base and vibrates the object while being connected and connected by the damper. It is characterized by comprising a calculation means for obtaining the Young's ratio of the measurement object by substituting the response magnification and the phase difference obtained by the calculation means.

Further, in the viscoelasticity measuring device according to the present invention, the calculation means obtains the viscosity of the measurement object by approximating the measurement object to a flexible model in which the tip of the cantilever is flexed by applying a force. It is characterized in that the viscosity coefficient of the measurement object is further obtained by substituting the response magnification and the phase difference obtained by the calculation means into the equation showing the coefficient.

Further, in the viscoelasticity measuring device according to the present invention, the displacement detecting means has a camera for photographing the measurement object and the shaking table, and based on the image captured by the camera, the first displacement and the said. It is characterized by detecting a second displacement.

The viscoelastic measurement method according to the present invention for achieving the above object is a first displacement, which is a displacement of a predetermined point of the measurement object in a state where the shaking table on which the measurement object is placed is vibrated. And the first sine wave which is a sine wave which detects the second displacement which is the displacement of the predetermined point of the shaking table and shows the time change of the first displacement, and the sine wave which shows the time change of the second displacement. A second sine wave is generated, and the response magnification indicating the ratio of the amplitude of the first sine wave to the amplitude of the second sine wave and the phase difference between the first sine wave and the second sine wave are obtained. The object placed on the base is connected to the wall body erected on the base by a linear spring and is connected by a damper, and the base is vibrated to vibrate the object. It is characterized in that the Young rate of the measurement object is obtained by substituting the response magnification and the phase difference into an equation showing the Young rate of the measurement object obtained by approximating the vibration of the measurement object.

According to the viscoelasticity measuring device according to the present invention, the Young's modulus of the object to be measured can be obtained by using the vibration means, the displacement detecting means, the sine wave generating means, the calculating means and the calculating means. Therefore, the viscoelasticity of the object to be measured can be measured hygienically and accurately without pressing the object to be measured.

Further, according to the viscoelasticity measuring device according to the present invention, the Young's modulus and the viscosity coefficient of the object to be measured can be obtained, so that the state of the object to be measured can be known in more detail.

Further, according to the viscoelasticity measuring device according to the present invention, since the displacement detecting means detects the first displacement and the second displacement based on the image of the camera, the device can be simply configured.

According to the viscoelasticity measuring method according to the present invention, the response magnification obtained from the first sine wave indicating the time change of the first displacement of the object to be measured and the second sine wave indicating the time change of the second displacement of the shaking table. And the phase difference are substituted into the equation showing the Young's ratio obtained by approximating the vibration of the object to be measured in the vibration model. Therefore, it is not necessary to press the measurement target when determining the Young's modulus of the measurement target.

It is a schematic block diagram which made a part of one Example of the viscoelasticity measuring apparatus of this invention in the cross section. It is explanatory drawing which approximates the vibration of the measurement object to the vibration model. It is explanatory drawing which approximates the measurement object to a flexible model.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing an embodiment of the viscoelasticity measuring device of the present invention, and is shown by cutting out a part. The viscoelasticity measuring device 1 of this embodiment is a device that measures the viscoelasticity of the measuring object 2 by vibrating the measuring object 2. Here, the object to be measured 2 may be elastically deformed by vibration, and may be, for example, a food pudding. As shown in FIG. 1, the viscoelasticity measuring device 1 of this embodiment includes a vibration means 3, a displacement detecting means 4, a sine wave generating means 5, a calculating means 6, and a calculation means 7.

The vibrating means 3 has a vibrating table 8 on which the measurement object 2 is placed, and is a means for vibrating the vibrating table 8. The vibrating means 3 of the present embodiment includes the shaking table 8, a support base 9 on which the shaking table 8 is supported, and a driving means 10 of the shaking table 8.

The shaking table 8 is formed in a substantially rectangular plate shape with the left-right direction as the longitudinal direction, and is arranged with the plate surface facing up and down. Legs 11 are formed on the front and rear ends of the lower surface of the shaking table 8 so as to be separated from each other to the left and right. Each leg 11 is formed in the shape of a rod having a substantially quadrangular vertical cross section, and is formed on the lower surface of the shaking table 8 along the left-right direction. As will be described later, an engaging portion with the driving means 10 is formed at the right end portion of the upper surface of the shaking table 8.

The support base 9 is formed in a substantially rectangular plate shape with the left-right direction as the longitudinal direction, and is arranged with the plate surface facing up and down. Rails 12 are formed on the front and rear ends of the upper surface of the support base 9 so as to be separated from each other to the left and right. Each rail 12 has a rod shape having a substantially quadrangular vertical cross section, and a groove portion 13 that opens upward on the upper surface is formed along the left-right direction.

The drive means 10 is, for example, a motor and is provided on a table 14 supported by a support base 9. The table 14 is formed in a substantially rectangular plate shape with the front-rear direction as the longitudinal direction, and is arranged with the plate surface facing up and down. A plurality of (three in the illustrated example) support columns 15 are formed so as to extend downward at both front and rear ends of the lower surface of the table 14 so as to be separated from each other in the left-right direction. The support pillar 15 of the table 14 is erected on the support base 9 and is arranged above the support base 9. A motor 10 is provided on the upper surface of the table 14.

As shown in FIG. 1, the shaking table 8 is supported by the support base 9 by inserting each leg portion 11 into the groove portion 13 of the rail 12. Therefore, the shaking table 8 can reciprocate in the left-right direction along the rail 12 with respect to the support base 9. Above the shaking table 8 supported by the support base 9, the motor 10 is arranged via the table 14 as described above. At this time, the motor 10 is arranged with its output shaft 16 facing downward. An eccentric cam 17 having a substantially circular shape in a plan view is provided at the tip of the output shaft 16 of the motor 10. The eccentric cam 17 is engaged with the cam follower 18, which is the engaging portion formed on the shaking table 8. The cam follower 18 has a substantially quadrangular frame shape in a plan view, and the left and right lengths in the frame are formed to be substantially the same as the diameter of the eccentric cam 17, and the cam follower 18 opens upward at the rear end portion of the upper surface of the shaking table 8. Is provided. An eccentric cam 17 provided on the output shaft 16 of the motor 10 is housed in the frame of the cam follower 18, and the shaking table 8 and the motor 10 are connected to each other.

With such a configuration, the vibrating means 3 can reciprocate the shaking table 8 in the left-right direction by driving the motor 10. For example, by driving the motor 10 at a constant speed, the shaking table 8 can be vibrated in a single string. Therefore, the pudding can be shaken by reciprocating the shaking table 8 with the pudding, which is the object to be measured 2, placed on the shaking table 8 via the plate 19. Here, a rubber sheet is provided on the upper surface of the shaking table 8 so that the dish 19 on which the pudding is placed does not slip during vibration. In this embodiment, the cam is designed so that the stroke is 10 mm (amplitude is 5 mm).

The displacement detecting means 4 is a means for detecting the displacement of the measuring object 2 and the displacement of the shaking table 8 in a state where the shaking table 8 on which the measuring object 2 is placed is vibrated. Specifically, the first displacement, which is the displacement of the predetermined point of the measurement object 2, and the second displacement, which is the displacement of the predetermined point of the shaking table 8, are detected. The displacement detecting means 4 of the present embodiment has a camera 20 for photographing the measurement object 2 and the shaking table 8, and the first displacement of the measuring object 2 and the shaking table 8 are based on the image captured by the camera 20. It detects the second displacement of. Typically, the displacement detecting means 4 includes the above-mentioned camera 20 and a trajectory creating unit 21 connected to the camera 20.

The camera 20 can shoot a moving image, and is referred to as a high-speed camera in this embodiment. The camera 20 is provided so as to intersect the direction of the reciprocating motion of the shaking table 8. In this embodiment, since the shaking table 8 reciprocates in the left-right direction, the camera 20 is arranged in front of the vibrating means 3. The image taken by the camera 20 is image-analyzed by the trajectory creating unit 21. Specifically, conventionally known video analysis is performed to obtain orbital data of a predetermined point of the measurement object 2 and orbital data of a predetermined point of the shaking table 8. Since both orbital data obtained here are distances on the image, they are converted into actual distances. Here, since the camera 20 is arranged in front of the vibrating means 3, the predetermined point of the pudding which is the measurement object 2 is on the surface of the measurement object 2 at the upper left corner portion of the front view substantially trapezoidal shape. Set. On the other hand, a predetermined point of the shaking table 8 is set at the upper left corner portion of the front surface on the surface of the shaking table 8. In this embodiment, since the vibration of the measurement object 2 is photographed by the camera 20, the measurement object 2 other than the pudding is elastically deformed to such an extent that the elastic deformation during vibration can be photographed by the camera 20. It is supposed to be.

The sine wave generating means 5 is a means for generating a sine wave based on the displacement detected by the displacement detecting means 4. Specifically, a first sine wave, which is a sine wave indicating the time change of the first displacement of the measurement object 2, and a second sine wave, which is a sine wave indicating the time change of the second displacement of the shaking table 8, are created. Will be done. Here, the horizontal displacement of the orbital data obtained by the displacement detecting means 4 is regarded as the vibration displacement, and the time change of the measured vibration displacement is approximated to a sine wave.

The calculation means 6 is a means for obtaining the response magnification and the phase difference based on the first sine wave and the second sine wave generated by the sine wave generation means 5. Here, the response magnification is indicated by the ratio of the amplitude of the first sine wave to the amplitude of the second sine wave, that is, the amplitude of the first sine wave / the amplitude of the second sine wave. The phase difference is the phase difference between the first sine wave and the second sine wave, and is represented by the initial phase of the first sine wave-the initial phase of the second sine wave.

The calculation means 7 is a means for obtaining the Young's modulus and the viscosity coefficient indicating the viscoelasticity of the object to be measured 2. The Young's modulus of the measurement object 2 is obtained by substituting the response magnification and the phase difference obtained by the calculation means 6 into the equation showing the Young's modulus of the measurement object 2 obtained by approximating the vibration of the measurement object 2 to the vibration model. Is required. Further, the viscosity coefficient of the measurement object 2 is the response magnification and the phase difference obtained by the calculation means 6 in the formula showing the viscosity coefficient of the measurement object 2 obtained by approximating the measurement object 2 to the flexible model. Obtained by substituting. The obtained Young's modulus and viscosity coefficient are displayed on a display means such as a display, stored in a storage means, or printed out in a predetermined format. The details of the method of obtaining Young's modulus by approximating the vibration model and the method of obtaining the viscosity coefficient by approximating the flexible model will be described later.

Next, a viscoelasticity measuring method for measuring the viscoelasticity of the object to be measured 2 will be described using the viscoelasticity measuring device 1 of the present embodiment. In the viscoelasticity measuring method of this embodiment, first, a dish 19 on which the pudding, which is the object to be measured 2, is placed is placed on the shaking table 8 of the vibrating means 3. In the state where the shaking table 8 on which the measurement object 2 is placed is vibrated in this way, the first displacement and the second displacement are detected by the displacement detecting means 4. At this time, the shaking table 8 is vibrated at a constant frequency. Then, the first sine wave and the second sine wave are generated by the sine wave generation means 5. Here, when the displacement and amplitude of the shaking table 8 are x (t) and A, and the displacement and amplitude of the measurement object 2 are x'(t) and A', each measurement data is approximated by the following equation. .. In each of the following equations, ω is the angular velocity, t is the time, and φ is the initial phase.

After the generation of the first sine wave and the second sine wave, the response magnification and the phase difference are obtained by the calculation means 6. Specifically, the response magnification and the phase difference can be obtained from the approximation result of the measurement data to the sine wave. The response magnification T and the phase difference θ are obtained by the following equations.

Using the obtained response magnification and phase difference, the Young's modulus of the measurement object 2 is obtained by the arithmetic means 7. As described above, this is done by substituting the response magnification and the phase difference into the equation showing the Young's modulus of the measurement object 2 obtained by approximating the vibration of the measurement object 2 to the vibration model.

FIG. 2 is an explanatory diagram that approximates the vibration of the measurement object to the vibration model. As shown in this figure, the object 22 is mounted on the base 23 and is connected to the wall body 24 erected on the base 23 by a linear spring 25 which is a primary spring and is also a damper. Connected at 26. In this state, the base 23 is placed on the shaking table 8 and the shaking table 8 is vibrated in the horizontal direction (horizontal direction on the paper surface of FIG. 2), which is the above-mentioned vibration model. The vibration by the vibration means 3 of 2 is approximated. A rubber sheet is provided on the upper surface of the shaking table 8 so that the base 23 does not shift with respect to the shaking table 8 during vibration. Here, when the mass of the object 2 to be measured is m, the displacement amount in the horizontal direction of the object 2 to be measured is _x , the damping coefficient is c, the spring constant is k, and the displacement amount of the shaking table 8 is x0, the following The equation of motion of is obtained.

Forced vibration is applied to the object to be measured 2 for measurement. When X ₀ is the amplitude of the vibration of the shaking table 8, ω is the frequency of the vibration, and t is the time, the displacement amount x ₀ of the shaking table 8 is defined by the following equation.

When the measurement object 2 swinging on the shaking table 8 is defined by the linear spring 25 and the damper 26, the phase difference θ output is as follows.

When the amplitude of the vibration of the object to be measured 2 is X, the response magnification T to the input forced vibration is obtained by the following equation.

Here, it is assumed that the phase difference θ and the response magnification T are observed for any forced vibration. At this time, the spring constant k and the damping coefficient c satisfying the observed phase difference θ and the response magnification T are obtained by the following equations.

However, when the observed phase difference is zero, the result cannot be obtained by the above-mentioned method. Here, the spring constant is obtained by the following equation by using the fact that the phase difference becomes zero when the damping coefficient is zero.

The Young's modulus of the object to be measured 2 is derived from the spring constant and the damping coefficient obtained as described above. Assuming that the object to be measured 2 is an elastic body, the elastic energy stored in the object 2 to be measured by the load is obtained. The load applied to the measurement object 2 is P, the height of the measurement object 2 is L, the arbitrary height is x _L , the Young's modulus of the measurement object 2 is E, and the cross section in the shear direction at the arbitrary height x _L is 2. When the next moment is I, the elastic energy U is obtained by the following equation.

In this embodiment, since the measurement object 2 is a pudding, the shape of the measurement object 2 is approximated to a truncated cone shape. In this case, when the relationship between the diameter d ₀ of the lower surface of the object to be measured 2 and the cross-sectional diameter d of the arbitrary height x _L is defined using the rate of change a of the diameter, the cross section in the shear direction at the arbitrary height x _L. The second moment I is obtained by the following equation.

The diameter d ₀ of the lower surface is obtained by directly measuring the object 2 to be measured. Further, the rate of change a of the diameter is calculated from the measured value of the diameter at x _L = L. From the above, the elastic energy of the truncated cone-shaped object 2 to be measured can be obtained by the following equation.

Here, by partially differentiating the elastic energy U with respect to the load P, the amount of deflection δ of the measurement object 2 can be obtained. The amount of deflection δ of the object to be measured 2 is as follows.

When the spring constant is k = P / δ, the Young's modulus E of the object to be measured 2 is derived from the following equation from the spring constant k obtained as described above.

Therefore, by substituting the response magnification T and the phase difference θ obtained by the calculation means 6 into the equations 9 and 17, the Young's modulus of the measurement object 2 can be obtained. In this way, the Young's modulus of the measurement object 2 is calculated by substituting the response magnification and the phase difference into the equation showing the Young's modulus of the measurement object 2 obtained by approximating the vibration of the measurement object 2 to the vibration model. Desired. In this embodiment, in addition to the Young's modulus of the measurement object 2, the viscosity coefficient of the measurement object 2 is obtained by the calculation means 7 by using the response magnification and the phase difference obtained by the calculation means 6. As described above, this is done by substituting the response magnification and the phase difference into the equation showing the viscosity coefficient of the measurement object 2 obtained by approximating the measurement object 2 to the flexible model.

FIG. 3 is an explanatory diagram that approximates the measurement object to the flexible model. In this embodiment, first, since the measurement object 2 is a pudding, the shape of the measurement object 2 is approximated to a truncated cone shape. Here, when the diameter of the bottom surface of the object to be measured 2 is d ₀ , the rate of change in diameter is a, the arbitrary height is x _l , and the pi is π, the moment of inertia of area at the arbitrary height is as follows. Indicated by the formula.

In this way, the shape of the object to be measured 2 is approximated to the shape of a truncated cone, and the bottom surface thereof is fixed to the installation location to form a truncated cone-shaped cantilever 27. For the displacement x of the tip of the truncated cone beam 27 when an arbitrary weighted F is applied, the derivative of the deflection angle (F (L-x _l ) / EI) is integrated twice, where L is the height of the truncated cone beam 27. Is sought after. However, Young's modulus is E, and the constants of integration are c ₁ and c ₂ .

The deflection angle and the deflection of the bottom surface of the truncated cone (x _l = 0) are set to 0, and the constants c ₁ and c ₂ are obtained.

By arranging the above equations, the displacement x of the tip of the truncated cone beam 27 when an arbitrary weight F is applied can be obtained by the following equation.

Next, assuming a state in which the viscosity coefficient of the object ₂ to be measured does not exist, the relationship between the time change (F1 _−F2 ) / Δt of the force at the tip of the beam 27 and the strain rate at an arbitrary position is obtained. As shown in the enlarged view of the bent cone beam 27 in FIG. 3, the radius of curvature of the enlarged portion is ρ, the curvature is dθ / ds, and the arbitrary distance from the neutral plane is y. At this time, the strain ε _xl at the position of an arbitrary height _xl and the distance y from the neutral plane is obtained by the following equation.

The stress σ _xy at any height _xl and at a distance y from the neutral plane is obtained from Hooke's law.

The moment M applied to the arbitrary height is obtained from Young's modulus E, the moment of inertia of area I, and the radius of curvature ρ.

From the above equations 22 to 24 and the equation 18 of the defined moment of inertia of area, the strain ε _xl at the position of an arbitrary height _xl and the distance y from the neutral plane can be obtained by the following equation.

Here, consider changing the strain ε _xly at an arbitrary position with time. The change of the strain at an arbitrary position from ε _xly1 to ε _xly2 at a constant velocity within the time of Δt is defined as the strain rate at an arbitrary position (ε _xly1 −ε _xly2 ) / Δt. At this time, the force change (F ₁ − F ₂ ) satisfying an arbitrary strain rate (ε _xly1 −ε _xly2 ) / Δt is as shown in the following equation.

Further, assuming a state in which the viscosity coefficient of the object 2 to be measured does not exist, the relationship between the time change of the force at the tip of the beam 27 ₍ F1 _−F2 ) / Δt and the deflection speed of the tip is obtained. The change of the displacement of the tip from x ₁ to x ₂ at a constant velocity within the time of Δt is defined as the deflection speed of the tip (x ₁ − x ₂ ) / Δt. At this time, the force change (F ₁ − F ₂ ) satisfying an arbitrary deflection velocity (x ₁ − x ₂ ) / Δt is as follows.

The relationship between the flexure rate and the strain rate is derived from the analysis results. In Equation 26 and Equation 27, the values of force changes (F ₁ -F ₂ ) are shared. Therefore, the following formula can be obtained from the formulas 26 and 27. At this time, the pi and Young's modulus E are eliminated from the following equations.

The strain rate satisfying any deflection speed is obtained by the following equation. Since this equation does not include Young's modulus E, the relationship of the following equation holds at any Young's modulus.

Here, it is assumed that the elastic modulus of the object to be measured 2 does not exist and only the viscosity coefficient exists. At this time, it is assumed that the tendency of the deflection curve of the object to be measured 2 coincides with the case where only the elastic modulus of the object to be measured 2 exists. First, the viscosity coefficient is μ, and the stress _σ'xl caused by the viscosity at an arbitrary position of the beam 27 is calculated from the strain rate.

Next, the moment at an arbitrary position of the beam 27 generated by the viscosity is obtained. This is obtained by integrating the stress generated in the cross section at an arbitrary position by the area. Therefore, the moment at an arbitrary position of the beam 27 caused by the viscosity is as shown in the following equations according to the equations 29 and 30.

At this time, the integration part shown in the equation of Equation 31 agrees with the definition of the moment of inertia of area.

In addition to this, the following equation showing the relationship between the force F'generated at the tip due to viscosity and the moment at an arbitrary position.

Therefore, the following equation is obtained. In this equation, all x _l indicating an arbitrary height are eliminated, and all other parameters are fixed values. Therefore, in the following equation, it can be confirmed that the relationship between the force F'generated at the tip due to the viscosity and only the displacement speed of the tip is shown.

An equation showing the definition of the attenuation coefficient c

And the equation 34 gives the relational expression between the equivalent damping coefficient and the viscosity coefficient as follows.

Therefore, the viscosity coefficient of the object to be measured 2 can be obtained by substituting the response magnification T and the phase difference θ obtained by the calculation means 6 into the equations 10 and 36. In this way, the viscosity coefficient of the measurement object 2 is obtained by substituting the response magnification and the phase difference into the equation showing the viscosity coefficient of the measurement object 2 obtained by approximating the measurement object 2 to the flexible model. Be done.

In the case of this embodiment, the measurement object 2 is vibrated, and the first sine wave indicating the time change of the first displacement of the measurement object 2 and the second sine wave indicating the time change of the second displacement of the shaking table 8 are shown. Therefore, the response magnification and the phase difference can be obtained. Then, the Young's modulus of the measurement object 2 is obtained by substituting the response magnification and the phase difference into the equation showing the Young's modulus obtained by approximating the vibration of the measurement object 2 to the vibration model. Therefore, the viscoelasticity of the measurement object 2 can be measured without pressing the measurement object 2. Conventionally, since the measurement target 2 is pressed for measurement, when the same measurement target 2 is measured a plurality of times, the measurement target 2 may be hardened and its characteristics may change. In this case, the measurement results of the second and subsequent times are significantly different from the measurement results of the first time, and accurate values cannot be measured. On the other hand, according to this embodiment, since there is no pressing, the characteristics of the measurement object 2 do not change even if the same measurement object 2 is measured a plurality of times, and the measurement is accurate. Can be done.

Further, in the case of this embodiment, the viscosity coefficient of the measurement target 2 is measured in addition to the Young's modulus of the measurement target 2. Therefore, the viscoelasticity of the object to be measured 2 can be known in more detail. As described above, the viscosity coefficient of the object to be measured 2 can be measured without pressing the object 2 to be measured. Further, in the case of the present embodiment, since the displacement detecting means 4 has the camera 20, the device 1 can be simply configured and the cost of the device 1 can be reduced.

The present invention is not limited to the above configuration, and can be appropriately modified. For example, the configuration of the vibrating means 3 is not limited to the configuration of the above embodiment, and conventionally known ones are used.

INDUSTRIAL APPLICABILITY The present invention can be suitably used when measuring the viscoelasticity of a measurement object without pressing the measurement object.

1 Viscoelasticity measuring device 2 Measurement object 3 Vibration means 4 Displacement detection means 5 Sine wave generation means 6 Calculation means 7 Calculation means 8 Vibration table 20 Camera 22 Object 23 Base 24 Wall 25 Linear spring 26 Damper

Claims (4)

A vibrating means that has a vibrating table on which an object to be measured is placed and vibrates the vibrating table,
With the shaking table on which the measurement object is placed vibrated, the first displacement, which is the displacement of a predetermined point of the measurement object, and the second displacement, which is the displacement of the predetermined point of the shaking table. Displacement detection means to detect
The first sine wave, which is a sine wave indicating the time change of the first displacement detected by the displacement detecting means, and the second sine wave, which is the sine wave indicating the time change of the second displacement detected by the displacement detecting means. A sine wave generation means that generates a sine wave,
Based on the first sine wave and the second sine wave generated by the sine wave generation means, a response magnification indicating the ratio of the amplitude of the first sine wave to the amplitude of the second sine wave, and the first sine wave. A calculation means for obtaining the phase difference between the wave and the second sine wave, and
The object placed on the base is connected to the wall body erected on the base by a linear spring and is connected by a damper, and the base is vibrated to vibrate the object. By substituting the response magnification and the phase difference obtained by the calculation means into the equation showing the Young's modulus of the measurement object obtained by approximating the vibration of the measurement object, the Young's modulus of the measurement object is obtained. A viscoelasticity measuring device characterized by being provided with a required calculation means. The calculation means is obtained by the calculation means in an equation showing the viscosity coefficient of the measurement object obtained by approximating the measurement object to a flexible model in which a force is applied to the tip of the cantilever to bend the cantilever. The viscoelasticity measuring apparatus according to claim 1, wherein the response magnification and the phase difference are substituted to further obtain the viscosity coefficient of the measurement object. The displacement detecting means has a camera for photographing the measurement object and the shaking table, and detects the first displacement and the second displacement based on the image captured by the camera. Item 1 or the viscoelasticity measuring device according to claim 2. With the shaking table on which the measurement object is placed vibrated, the first displacement, which is the displacement of the predetermined point of the measurement object, and the second displacement, which is the displacement of the predetermined point of the shaking table, are detected. Then, a first sine wave, which is a sine wave indicating the time change of the first displacement, and a second sine wave, which is a sine wave indicating the time change of the second displacement, are generated, with respect to the amplitude of the second sine wave. The response magnification indicating the ratio of the amplitude of the first sine wave and the phase difference between the first sine wave and the second sine wave are obtained, and the object placed on the base is erected on the base. Young of the measurement object obtained by approximating the vibration of the measurement object to a vibration model that vibrates the base and vibrates the object while being connected to the wall by a linear spring and connected by a damper. A viscous elasticity measuring method, characterized in that the Young rate of the measurement object is obtained by substituting the response magnification and the phase difference into an equation showing the rate.

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