JP2008096315A - Method and device for evaluating elasticity of object having smooth outer periphery based on deformation of outer periphery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for simply and stably measuring average elasticity of a measurement object not depending on the size of the measurement object and an elasticity evaluation technique not depending on the size of the measurement object regarding a method and a device for measuring and evaluating elasticity of an object having a smoothly shaped outer periphery, such as the human arm. <P>SOLUTION: This device comprises a means to wind a belt around a target object of which elasticity should be evaluated, pull the end of the wound belt, and measure the tensile strength generated on the belt, and a means to measure a change of length of a portion where the belt is wound around the measurement object. The device measures the change of length of the portion where the belt is wound around the measurement object and shows the elasticity of the measurement object. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for evaluating the elasticity or hardness of an object having a smooth outer periphery.

  In the medical field, there are diseases in which the hardness of the skin surface changes depending on lesions such as skin cancer and edema (swelling). In the diagnosis of such diseases, establishment of a quantitative measurement method for skin surface hardness is desired. In the health and welfare field, there is a need to measure muscle strength. Among the various declines that occur in the body with aging, particularly the decline in muscle strength directly leads to a decline in quality of life (QOL) of the elderly. . It is known that muscular strength is related to the hardness of the body part measured on the skin surface, and it is desired to easily measure the hardness of the skin surface. Similarly, in the sports field, muscle strength measurement, muscle fatigue measurement, and the like are performed by evaluating hardness, and a simple hardness measurement method is desired.

  In the industrial field such as food and processed rubber products, there are many products whose hardness is the index of quality when quality control is performed. For example, in the food field, it is necessary to measure hardness in order to realize the hardness of a rice ball that is accepted as a delicious taste by consumers as a performance evaluation index of an automatic machine that automatically holds a rice ball. The present invention is adaptable to these needs, and an object thereof is to provide an apparatus and a measuring method that have features that are simpler and more stable than conventional methods and that can measure average hardness at a time.

  As a conventional technique for measuring elasticity or hardness corresponding to the above-mentioned purpose in the medical field, there is an invention disclosed in Patent Document 1, in which air pressure is applied to the surface of an object, and deformation such as elasticity and viscosity is changed from the displacement at this time. It measures the characteristics. In this technique, the range that can be measured at a time is narrow, and when measuring elasticity over the entire object, it is necessary to perform measurement at many points. Patent Document 2 discloses a softness measuring device that quantitatively grasps the softness of a body tissue such as muscle and an analysis program thereof. It is a device with a function that can measure the hardness degree of the target part by detecting the surface wave generated around it by applying vibration from the predetermined measurement position to the target part, but the measurement range of hardness Is limited to the range in which vibration is applied, it is necessary to apply vibration to several places in order to perform the entire measurement.

  In the invention disclosed in Patent Document 1, air pressure is applied to one location of the object to be measured, and the deformation of the object to be measured is measured as a response, but the relationship between the applied pressure and the corresponding deformation is constant. In some cases, it is necessary to constrain the measurement object. In particular, it is desirable that the device is used for clinical use by a doctor because it is easy to handle with little burden.

In the applications of elasticity measurement described in the above-mentioned 0002 and 0003, it is important to obtain an average value of the entire elasticity value of the object to be measured, but a method for measuring local elasticity as in the prior art described above. In this case, it is necessary to calculate the average elasticity value of the whole from the measurement results at a large number of points in consideration of the inhomogeneity and anisotropy of the structure inside the measurement target object. For example, if you want to measure the elasticity of the arm as seen from the surface of the human arm, there are various tissues with different elasticity such as bones, tendons, and blood vessels in the arm, and the local elasticity changes depending on the position. In order to obtain a good elasticity, the conventional method requires measuring the entire circumference of the arm many times. As described above, the conventional technique has a problem in easily measuring the elasticity of an object.
Japanese Patent Laid-Open No. 2004-069668 JP 2005-040474 A

  A method and apparatus for measuring and evaluating the elasticity of an object having a smooth outer periphery, and providing a simple and stable method for evaluating the average elasticity of a measurement object regardless of the size of the measurement object. The task is to do. In other words, if a measurement object having the same hardness inherent in the material but different in size is simply evaluated by only the force and the deformation amount, the elasticity of the object cannot be accurately evaluated. Large objects appear to be soft, and vice versa for small objects. This is a problem for a measurement target having individual differences such as a human arm. Therefore, it is an important issue to provide an elasticity evaluation method that is not affected by the size of the measurement target. Note that the above-described object having a smooth outer periphery means that the shape of the outer periphery of the cross section of the object to be evaluated does not have a sharp convex portion, a small-angle ridge, or the like. For example, a triangular prism or a quadrangular prism is not a target in cross section, but a polygonal prism having a larger cross section may be regarded as a smooth shape in the present invention.

  An apparatus or an evaluation method for evaluating the elasticity of an object having a smooth outer periphery, in which a band is wound around an object whose elasticity is to be evaluated, and a tensile force is applied by pulling an end of the wound band And means for measuring the tensile force generated in the band by means for applying the tensile force, and means for acquiring the amount of change in the length of the portion where the band is wound around the elastic evaluation object. In the above-described configuration, a tensile force is applied to the belt by means for applying a tensile force, and when the tension measuring means detects that the tensile force has reached a predetermined tension, and the belt is elastic when the tensile force is continuously applied. Measure the amount of change in the length of the band wound around the object to be evaluated during the time when the state where the length of the portion wrapped around the evaluation object is no longer changed, and the amount of change in the length of the band The elasticity of the object to be evaluated is evaluated based on the measured tensile force. That is, the degree of reduction in the length of the outer periphery of the cross section of the evaluated portion, which is caused by applying a compressive force to the evaluated portion by pulling the belt wound around the elastic evaluation target object, corresponds to the hardness or elasticity of the portion. Using the phenomenon, the degree of decrease in the outer circumferential length of the cross section is calculated from the measurement data of the position of the end of the band wound around the object to be evaluated, and the hardness or the ratio of the calculated value and the tensile force measurement value is calculated. It is configured to perform elasticity evaluation. Note that the position of the end of the band is changed by pulling the band wound around the object to be evaluated for elasticity, and the measured value of the end position is referred to as “the tensile distance of the band” and “the end position of the band”. To do.

  FIG. 1 is a diagram showing the basic configuration and operation of the present invention. In FIG. 1, reference numeral 1 denotes a cross section of an object to be measured and evaluated for elasticity. A typical measurement target is a human arm, and the skin surface hardness is quantitatively used to diagnose whether the skin surface hardness changes depending on lesions such as skin cancer and edema (swelling). This is the case when measuring and evaluating. In FIG. 1, reference numeral 2 denotes a band for elasticity evaluation, which has a string-like or tape-like shape, is a flexible material that can be wound around an object to be evaluated, and is applied to the band 2 It is necessary that the force does not cause an elongation that affects the elasticity evaluation. In addition, the band needs to have a sufficient width so as not to cause excessive surface pressure locally on the surface of the object to be measured. In the following description and claims, “band” means a string or tape-like material that satisfies the above requirements.

  In FIG. 1, as a means for applying a tensile force to the band 2 wound around the elastic evaluation target part of the object 1 to be evaluated, after the band 2 is wound around the evaluation target part, one end thereof is connected to the fixed point 6 and the other end Is connected to a tension means 3 comprising a moving mechanism (hereinafter referred to as a linear slider) having an actuator 3a that moves linearly by a driving device. The actuator 3a of the pulling means 3 can pull the end of the band 2 in the right direction in FIG. Further, a tensile force measuring means 4 (for example, a force sensor such as a strain gauge or a load cell) is incorporated at a connection point between the actuator 3a and the belt 2 to enable measurement of a tensile force applied to the belt 2. The tension means 3 incorporates a position measuring means 5a (for example, a magnetic distance sensor, an encoder or the like position or distance sensor) of the actuator 3a to measure the tensile distance. That is, the movement distance of the end of the belt 2 is measured by measuring the movement distance of the actuator 3a of the linear slider, which is the tension means, by the position measuring means 5a, and is set as the tension distance of the belt 2. In FIG. 1, where the two ends of the band 2 wound around the evaluated part 1 seem to intersect at A, are both ends of the band 2 shifted in the front and back directions in FIG. 1 to avoid mutual contact? As shown in the AA arrow view of FIG. 1, a ring 13 having a mouth shape or other appropriate shape is connected to one end of the belt 2, and the other end of the belt 2 is arranged to pass through the same ring. And pay attention to avoiding mutual contact.

  In FIG. 4, the control device 14 outputs a signal for driving the tension means 3 to which the linear slider is applied, and inputs the signals of the tension force measurement means 4 and the position measurement means 5a of the actuator 3a to calculate elasticity evaluation. To do. First, the belt 2 is wound around the object to be elastically evaluated, and a signal for driving the belt 2 in the pulling direction is output from the linear slider drive control unit 14a to the actuator 3a. The elasticity evaluation unit 14b monitors the measured tensile force value and the position of the actuator 3a, and stores the position of the actuator 3a when the measured value of the tensile force measuring means 4 reaches the preset tensile force f1 (stored position). After that, the position change of the actuator 3a is monitored and the position of the actuator 3a is measured and stored when the change amount of the same position is within a predetermined value (the stored position is set to L2). . Here, the value of | L1-L2 | (assumed as Δx) is regarded as when the tensile force applied to the band 2 reaches the set value (f1), that is, the tensile force is applied to the band 2 wound around the elastic object to be evaluated. The actuator 3a (i.e., until the position change that has occurred in the actuator 3a stops as a result of the radius of the object to be evaluated wound around the band 2 being tightened by the tensile force applied to the band 2 to reduce its radius). This is the moving distance of the end of the band 2 and corresponds to the tensile distance of the band 2. Further, the value of Δx = | L1-L2 | is obtained by applying a tensile force to the band 2 after the cross-sectional outer peripheral length of the portion to be evaluated wound around the band 2 at the time when the tensile force of the band 2 is f1. It is proportional to the difference in the outer peripheral length after decreasing. Furthermore, the elasticity evaluation part 14b memorize | stores the tensile force (it is set to f2) added to the belt | band | zone 2 when the position of the actuator 3a becomes L2. As shown in FIG. 4, the control device 14 can set a maximum tensile force (fm), and when the tensile force reaches fm, the driving of the tension means 3 (linear slider in the case of FIG. 4) is stopped. To do. Here, the control means 14 does not need to be a single device, and can be an assembly of devices and units having the above functions.

  The ratio of the amount (Δx = | L1-L2 |) proportional to the change in the outer peripheral length of the cross-section of the part to be evaluated and the change in tensile force (f2-f1) (( It is possible to evaluate the elastic coefficient of the target object by f2-f1) / Δx.

  The ratio ((f2−f1) / Δx) depends on the size of the object to be evaluated, and requires correction based on the size of the object to be evaluated. The correction method will be described below. In addition, the meaning of the variable and coefficient used for Formula (1)-(6) shall be used by the same meaning also in description of a claim. In FIG. 1, the volume of the portion of the object 1 to be evaluated, where V is the volume of the portion covered with the band 2 wound around the portion, and the change in compression pressure dp applied to the same portion by the band 2 It is assumed that a change in dV change occurs in the volume. Assuming that the volume elastic modulus of the object to be evaluated subjected to compression from the outside by the band 2 is K, the relationship between the volume change dV and the compression pressure change dp is expressed by Equation (1).

  Assuming that the cross section of the elastic evaluation object is approximately a circle, the radius is r, the width of the band is B, dr is the change in radius r corresponding to the change in compression pressure dp, and f is the tensile force applied to the band. Equations (1) to (6) are obtained.

The radius of the object to be evaluated in the initial stage (instantaneous state where the tensile force f1 is applied to the band 2) is set to r _0, and the tensile force f1 applied to the band 2 at that time is a small value and approximates f1 = 0 to the equation ( 6) is integrated to obtain equation (7). Further, when σ and ε are expressed as in the equations (8) and (9), the evaluation value K of the bulk modulus regardless of the size of the object to be evaluated can be calculated as in the equation (10). σ represents stress and ε represents tension.

By using the bulk modulus obtained by the equation (10), the elasticity of the measurement object can be evaluated regardless of the size of the object. F used to obtain the elastic modulus K by the equation (10) is f = f2-f1, but f1 and f2 are measured as the tensile force applied to the band 2 as described in the above-mentioned 0011 (however, the equation ( In the process of 6), it is a value approximated to f1 = 0 for simplification. In addition, the radii r ₀ and r in the equations (7) to (9) are the states in which the band 2 is not wrapped around the elastic evaluation object as shown in the state 1 of FIG. The position of the actuator 3a at Lb is Lb, the band 2 wound around the object to be elastically pulled is pulled, and the calculation formula r ₀ using the actuator position L1 when the tensile force reaches f1 described in 0011 (state 2). = (Lb−L1) / 2π. Further, it can be calculated by r = r ₀ − (L2−L1) / 2π.

The elastic coefficient calculation unit 14c in FIG. 4 has calculation means for performing the calculation described above and the calculation of the values r ₀ and r described in 0016, so that the Lb, L1, L2, f1, and f2 Can be used to calculate and output the evaluation value K of the elastic modulus.

  As a means for pulling the belt 2, in addition to the linear slider, as shown in FIG. 2A, the end of the belt 2 is wound around a drum 21 driven by a servo motor 20, and the drum is rotated to pull the belt 2. It is also possible to add. A change in the winding length of the band 2 around the object 1 to be evaluated, that is, the radius of the target object is added to the drum by the rotary encoder 22 and the tensile force is measured by a tensile force measuring means 23 inserted into a part of the band 2. You may arrange | position so that it may measure with a strain gauge, a load cell, etc.

As shown in FIG. 2 (a), the end of the belt 2 is connected to one end or an extended portion thereof to the fixing point 6, and the other end or an extended portion thereof is connected to the tension means 3, for example, a linear slider. It is also possible to connect or wind around the drum 21. As another configuration, as shown in FIG. 2B, both ends of the belt 2 can be connected to a device for applying a tensile force. In the case of FIG. 2 (a), the movement amount of the end of the band 2 pulled by the tension means provided at one end of the band 2 is L1 and L2, but in the case of FIG. 2 (b) Is the amount of movement at both ends of the band 2, and the total (Δxa + Δxb) of the movement amounts at the respective ends (the amounts of movement are Δxa and Δxb) measured when the band 2 is tensioned and tensioned is described above. And the total amount of movement (Δxa + Δxb) when both ends no longer move is made to correspond to L2. Moreover, let f1 and f2 be the average values of the tensile forces applied to both ends. That is, the tension means 10a and 10b shown in FIG. 2 (b) are used to tension the band 2 and each tensile force measuring means (corresponding to a point in time when a predetermined tensile force (f ₁ ) is generated at each end of the band 2). 4a, 4b) _f 1a the tensile force of each detected _{is, f 1b,} each tension means (10a, tensile force measuring means (4a between the time or subsequent movement is stopped in 10b), 4b) is detected It is possible to obtain f1 = (f _1a + f _1b ) / 2 and f2 = (f _2a + f _2b ) / 2 where f _2a and f _2b are the obtained tensile forces.

  When the belt 2 is pulled by the pulling means 3, an error occurs in the evaluation value when a large frictional force acts between the belt 2 and the elastic object to be evaluated. As a means for preventing such an error, the effect of friction is prevented by changing the pulling speed or pulling force of the pulling means 3 in a short time. For example, in FIG. 4, the tensile force applied to the belt 2 is increased by superimposing the vibration signal 14 d on the drive control unit 14 a of the linear slider, and changing the linear slider movement drive speed signal to a slow flux with respect to the average speed setting. Configure to be vibrational.

  When the belt 2 is pulled, it may be pulled by power such as a motor or may be pulled manually. In order to reduce the influence of frictional force and uniformly apply force to the measurement target, apply a lubricant between the band and the measurement target, or select a material with a low friction coefficient as the band material It is desirable.

  When the band 2 is wrapped around the object to be evaluated and connected to the tension means 3, the end of the band 2 is connected to the tension means or the fixing point via the 1 or 2 roller 7 (or 7a, 7b) as shown in FIG. It is desirable to arrange so as to be connected. When two rollers (7a, 7b) are used, they should be parallel to the evaluation section of the object to be evaluated as parallel as possible at right angles, and the distance (rr) between the centers of both rollers is the size of the object to be evaluated. It is necessary to make it as small as possible compared with (or radius r).

  The apparatus and method for evaluating the elasticity of an object having a smooth outer periphery of the present invention is simple, not affected by the size of the object to be evaluated, and does not depend on the skill and experience of the evaluator. In addition, it is possible to obtain an average elastic modulus over the entire circumference of the object to be evaluated by a single measurement. This is an effect that could not be realized by the conventional method or apparatus.

  FIG. 6 shows a form for measuring the hardness of a human arm as a measurement target. The measuring device uses a band, a force sensor as a tension acquisition device, and a combination of a linear slider and a rotary encoder as a displacement acquisition device. Move the slider and tighten the arm to be measured with a belt. The tension f and the slider movement amount x at this time are sequentially taken in and stored in the arithmetic unit. The elastic characteristics of the target object can be evaluated from the stored force and slider movement amount by the method described above.

FIG. 7 shows the relationship between the measured tensile amount of the band and the tensile force using this measuring apparatus. The tensile amount x increases at a constant speed. In this case, it can be seen that the measurement object and the belt are in close contact with each other at the time of 8 seconds and a force is generated. FIG. 8 shows a plot obtained by converting the time series response into a change in radius and a change in force of the measurement object according to the equations (4) and (5). The bulk modulus K determined from the measurement data at this time was K = 7.2 × 10 ⁵ [Pa]. In order to verify the effectiveness of this measurement technique, as shown in Table 1, FIG. 9 shows the results of obtaining the elasticity for a total of six types of measurement objects, each having three types of diameters and two types of hardnesses. The soft measurement object matches the hardness of human skin. From this result, it can be seen that the elasticity can be accurately evaluated without depending on the size especially for the flexible object such as human skin.

  The process of performing the elasticity evaluation of the human arm according to the present invention will be described below.

  (Step 1) It is assumed that the band 2 has one end fixed and the other end connected to the tension means 3. When the tension means 3 is connected to both ends, the sum of the movement amounts of both ends is made to correspond to Lb described later. In response to a command from the control means 14, the tension means 3 is operated to pull the belt 2, and when the control means 14 receives a signal from the tensile force measurement means 4 and detects a tensile force of f 1 or more, the control means 14 detects the tension of the belt 2. The position of the connection point with the pulling means is input from the pulling distance measuring means, and the value is stored in the memory of the control means 14 as Lb.

  (Step 2) After that, the tension of the band 2 by the tension means 3 is once released, the band 2 is made into a loop shape, a human arm to be measured is inserted into the loop, and the band 2 is positioned on the measurement unit (See state 1 in FIG. 5).

  (Step 3) When the end of the band 2 is pulled in the same manner as in Step 1, and the control means 14 detects that the tensile force has reached f1 by the signal from the tensile force measuring means 4, the end position of the band 2 is pulled. The input value from the distance measuring means is stored as L1 in the memory of the control means 14 (see state 2 in FIG. 5).

  (Step 4) The tension means 3 is continuously operated by the control means 14, and the control means 14 detects that the position of the end portion of the belt 2 is not changed by the signal from the tension distance measurement means 5, and the tensile force at that time The signal of the measuring means 4 (corresponding to the tensile force f2) is stored in memory. For the sake of safety, the maximum value of the tensile force applied to the band 2 by the tension means 3 is set in the control means 14, and if the above set value is exceeded regardless of the change in the end position of the band 2 Stop and open the tensioning means. When applied to humans, the maximum tensile force is preferably about 25N.

Obtained in (step 5) the above steps, the memory was Lb, L1, arithmetic unit of the control unit 14 by the L2 data r to be used in calculation of equation (7) to (9), the _{r 1, r} 1 = ( Lb−L1) / 2π, r = r ₁ − (L2−L1) / 2π. Further f1 arithmetic unit of the control unit 14 and memory as described above, f2 and the r, performs computation according to Equation 4 using the r _1, calculates the elasticity evaluation coefficient K which is not affected by the diameter of the elastic evaluation object Output in the required form (display, print, etc.). Note that the above-described steps can be executed as a control function incorporated in the control means 14 (excluding step 2), and the pulling means 3 is operated using steps 1 to 5 as a manual operation, or the pulling is performed. It is also possible to obtain the elastic modulus evaluation value K by reading the measured values of the force measuring means 4 and the tensile distance measuring means 5 and calculating the equations shown in the equations (7) to (10).

  The device for evaluating the hardness of the human arm, the device for evaluating the hardness of food, and the method have important industrial uses, but there was no simple method in the past, and it was a troublesome and inaccurate method. The apparatus according to the present invention is highly effective in meeting industrial demands and has high industrial utility value.

It is explanatory drawing which shows the basic composition of this invention. It is explanatory drawing which shows the example of arrangement | positioning of the means to pull | pulp the belt | band | zone in this invention. It is a figure which shows arrangement | positioning of the roller which pulls the strip | belt in this invention. It is a block diagram of the control apparatus of this invention. It is explanatory drawing which shows the method of measuring the radius of the to-be-evaluated target object in this invention. It is a figure which shows an example of apparatus embodiment of this invention. It is a graph which shows the measurement result of the time change of the tension | tensile_strength of a belt | band | zone and the tension distance in embodiment of this invention. It is an experimental data which shows the relationship between the tension | tensile_strength ((epsilon)) added to the elasticity evaluation object, and stress ((alpha)). It is a graph which shows the result of the elasticity evaluation obtained in implementation of this invention.

Explanation of symbols

1 Object subject to elasticity evaluation (cross section)
2 belt 3 tension means 3a actuator for tension means 4 tension force measurement means 5 tension distance measurement means 5a actuator position measurement means 6 fixed point 7 roller 7a, 7b roller 10 linear motion moving mechanism (linear slider)
DESCRIPTION OF SYMBOLS 11 Linear slider actuator 12 Actuator position measurement means 13 Connection ring 14 Control apparatus 20 Drive means 21 Drum 22 Encoder 23 Force sensor

Claims (11)

An apparatus for evaluating the elasticity of an object having a smooth outer periphery,
Band 2, tension means 3 connected to the end of band 2 and pulling band 2, tensile force measuring means 4 for measuring the tensile force applied to band 2 by tension means 3, and tension means 3 being band 2 A pulling distance measuring means 5 for measuring the distance of the pulling movement, and a control device 14,
After the band 2 is wound around the elastic evaluation object 1, the tension means 3 is operated by the control means 14 to apply a tensile force to the band 2, and the tensile force applied to the band 2 by the detection signal of the tensile force measuring means 4 is The band 2 is pulled between the time when it is detected that the predetermined tensile force (f1) is reached and the time when it is detected that the change in the tensile distance of the band 2 is stopped by the detection signal of the tensile distance measuring means 5. Is obtained from the signal of the tensile distance measuring means 5, and the tensile force f2 at the time of stopping the change in the tensile distance of the band 2 is obtained from the signal of the tensile force measuring means 4, and from the obtained value The value of (f2-f1) / Δx is calculated, and the elasticity of the object having a smooth shape is characterized in that the elasticity value of the object 1 to be evaluated for elasticity is evaluated based on the calculated value. Evaluation device.   It has the point 6 which fixes the end of the belt | band | zone 2 of Claim 1, and the other edge part of the belt | band | zone 2 is connected to the tension | tensile_strength means 3, and is the edge part which is connected to the tension | tensile_strength means 3 Includes a tensile force measuring means 4 for measuring a tensile force applied to the band 2 and a tensile distance measuring means 5 for measuring a distance by which the tensile means 3 moves by pulling the band 2. The tension means 3 pulls the band 2; The band 2 generated between the time when the tensile force measuring means 4 detects that a predetermined tensile force (f1) is generated in the band 2 and the time when the change in the pulling distance of the band 2 by the tension means 3 stops. 2. The smooth shape according to claim 1, wherein the tensile distance is obtained by the tensile distance measuring means 5 and Δx, and the tensile force applied to the band 2 at the time of stopping the change in the tensile distance of the band 2 is f2. A device that measures and evaluates the elasticity of an object with an outer periphery. Each end of the band 2 according to claim 1 is connected to a tension means 3a or 3b. At each end of the band 2, a tensile force measuring means 4a or 4b and tension means 3a and 3b are connected to the band 2 A tensile distance measuring means 5a or 5b for measuring the distance of pulling
When each end of the band 2 is pulled by the pulling means 3a and 3b, and it is detected by the tensile force measuring means (4a or 4b) that a predetermined tensile force (f1) is generated at each end of the band 2 Until the stop of the change in the pulling distance at each end of the band 2 by each pulling means (3a or 3b), the tensile distance measurement of the band 2 generated at each end of the band 2 is measured. Means (5a or 5b), the distances being Δxa and Δxb for the respective ends of the band 2, and the tensile forces applied to the ends of the band 2 at the time of stopping the change in the pulling distance of the band 2 respectively. fa, fb,
Δx described in claim 1 is Δx = (Δxa + Δxb), f2 described in claim 1 is f2 = (fa + fb) / 2, and the value of (f2−f1) / Δx is calculated. The apparatus for evaluating the elasticity of an object having a smooth outer periphery according to claim 1.   After one end of the band 2 according to claim 1 is hung on a roller 7 arranged in the vicinity of the object to be evaluated for elasticity, or both ends of the band 2 are sufficient for the radius (r) of the object 1 to be evaluated After being hung on two rollers 7a and 7b arranged side by side in the vicinity of the same object 1 with a small distance rr, the end of the band 2 or its extension is connected to the fixed part 6 or the tension means 3. The apparatus for evaluating the elasticity of an object having a smooth outer periphery according to claim 1, wherein the apparatus has a smooth outer periphery.   5. The structure according to claim 1, wherein the pulling means according to claim 1 has a configuration in which an end portion of the belt 2 or an extension portion of the end portion is wound around a drum 21 driven by the driving means 20. A device that evaluates the elasticity of an object with a smooth outer periphery.   The smooth means according to any one of claims 1 to 4, wherein the pulling means 3 according to claim 1 has a configuration in which an end portion of the band 2 or an extension portion of the end portion is connected to a moving mechanism 10 that performs linear motion. A device that evaluates the elasticity of an object with an outer periphery of a simple shape.   The means 3 for applying a tensile force described in claim 1 is configured so that the tensile force of the belt 2 can be vibrated up and down with respect to a predetermined central tensile force. Item 7. An apparatus for evaluating the elasticity of an object having a smooth outer periphery according to Items 1 to 6. The tensile distance of the belt 2 when the tensile force of the belt 2 wound around the object to be elastically evaluated according to claim 1 reaches a predetermined value (f1) is measured by a tensile distance measuring means L1, When the change in the tensile distance of the belt 2 stops, the tensile distance of the belt 2 is L2, the tensile force applied to the belt 2 when the change in the tensile distance stops is f2, and the belt 2 is not wrapped around the elastic evaluation target object 1. In the state where the tension is linearly pulled, Lb is the tensile distance of the same band, and K is a coefficient for evaluating elasticity without being affected by the cross-sectional size of the object 1 to be evaluated, and K is calculated by the following equation. The apparatus for evaluating the elasticity of an object having a smooth outer periphery according to claim 1, wherein:

The configuration according to any one of claims 1 to 8, comprising a control means that operates according to the following steps (1) to (5), and evaluates the elasticity of an object having a smooth outer periphery. Device to do. However, step 2 can be manually operated.
(Step 1) When the tension means 3 is operated in accordance with a command from the control means 14 to pull the belt 2 and when the tensile force measuring means 4 is received and a tensile force of f1 or more is detected, the control means 14 The tensile distance is input and the value is stored in the memory as Lb.
(Step 2) The tension of the belt 2 by the tension means 3 is once released, the belt 2 is made into a loop shape, an elastic evaluation target is inserted into the loop, and the belt 2 is positioned on the evaluation target portion of the object.
(Step 3) When the end of the band 2 is pulled in the same manner as in Step 1 and it is detected that the tensile force has reached f1 by the signal from the tensile force measuring means 4, the tensile distance of the band 2 is determined from the tensile distance measuring means 5. Input the value and store it in memory as L1.
(Step 4) The tension means 3 is continuously operated by the control means 14, and the control means 14 detects that the change in the tension distance of the belt 2 has disappeared by the signal from the tension distance measurement means 5, and the tension distance is measured. 4, L2 and the signal of the tensile force measuring means 4 at that time are stored as f2.
(Step 5) The elastic evaluation coefficient K that is not influenced by the cross-sectional size of the object to be elastically evaluated is calculated from the Lb, L1, L2, and f2 obtained in the above steps and stored in memory according to the equation (1). . Using the apparatus having the configuration according to any one of claims 1 to 8, the elasticity of an object having a smooth outer periphery is evaluated by the operations of the following steps (1) to (5). Elasticity evaluation method.
(Step 1) When the tension means 3 is operated to pull the band 2 and when the tensile force measuring means 4 detects a tensile force of f1 or more, the pulling distance of the band 2 is input, and the value is set to Lb To do.
(Step 2) The tension of the belt 2 by the pulling means 3 is once released, the belt 2 is made into a loop shape, an elastic evaluation target is inserted into the loop, and the belt 2 is positioned on the evaluation target portion of the object.
(Step 3) When the end of the band 2 is pulled in the same manner as in Step 1 and it is detected that the tensile force has reached f1 by the signal from the tensile force measuring means 4, the tensile distance of the band 2 is determined from the tensile distance measuring means 5. Acquire and set the value to L1.
(Step 4) The tension means 3 is continuously operated, and it is detected by the signal of the tension distance measurement means 5 that the change in the tension distance of the belt 2 has disappeared, the tension distance is acquired from the tension distance measurement means 4 and L2, The signal of the tensile force measuring means 4 at that time is assumed to be f2.
(Step 5) The elastic evaluation coefficient K that is not influenced by the cross-sectional size of the object to be elastically evaluated is calculated from the Lb, L1, L2, and f2 obtained in the above steps and stored in memory according to the equation (1). .   10. The human skin elasticity evaluation apparatus according to claim 1, wherein the evaluation object is elasticity or hardness of a human body part.

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