Microparticle compression test device and microparticle compression test method

Abstract

To enable efficient testing of characteristics of a sample of many microparticles without making a mechanism of a test device complex as much as possible.SOLUTION: On an uppermost side surface of a sample placement portion 102 in a prismatic shape, a sample placement range 103 whose width-direction size is larger than its depth-direction size is provided, and a sample is placed, and positioning is performed in the width direction by performing imaging from the front side. The sample placement range 103 is made elongated so that as many samples as possible can be arranged in one row. Next, an indenter 104 held by a stage 106 is moved in the width direction to align with the sample, and the stage 106 is driven vertically downward to bring the indenter 104 into contact with the sample to compress the sample. The compression characteristics of the sample are evaluated on the basis of a test force during compression measured by a test force measurement portion 107 provided at a lower part of the sample placement portion 102, and a descending level of the stage 106 corresponding to a displacement of the indenter 104. The same procedure is automatically repeated for the next sample.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a microparticle compression testing device and a microparticle compression testing method for testing physical properties such as compressive strength of microparticles. [Background technology]

[0002] Devices and methods are known for measuring and testing the compressive strength and other properties (compression characteristics) of microparticles with particle diameters of 1 mm or less (e.g., several μm to several hundred μm). The types of microparticles studied include ceramics, resins, pharmaceuticals, cosmetics, and metals. These microparticles are often granules made by agglomerating fine particles with diameters of several μm or less. These microparticles are produced by mixing multiple components, granulated, or molded into a specific shape before being distributed or used. For example, in ceramic molding, in which granulated fine ceramic particles are filled into a mold, press-molded, and fired, microparticles with excessive hardness may remain uncrushed during molding, resulting in defective molded products. To prevent such defects, it is necessary to keep the compression characteristics of the microparticles within a specified range.

[0003] Several conventional techniques for microparticle compression tests are known. For example, in the granule property measuring device described in Patent Document 1, sample granules are manually placed on a measurement plate, the measurement plate is manually moved until the sample is directly under an indenter, and then the indenter is pressed down to apply pressure to the sample. The hardness and load deformation rate of the sample can be determined from images of the sample shape taken before and after pressure application and the compression load during pressure application.

[0004] Furthermore, according to the micro-compression testing machine described in Patent Document 2, granular samples are randomly scattered on a lower pressure platen that is movably held on an XY stage, and an image is taken from above. From the image, samples that can be subjected to a compression test alone are identified, and the XY stage and another stage are driven to move the lower pressure platen horizontally until the sample is directly below the indenter, and the Z stage is used to raise and lower the platen to determine the test position between the indenter and the sample. After that, a compression test can be performed via the indenter using a loading mechanism. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-365186 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-116349 Summary of the Invention [Problem to be solved by the invention]

[0006] The granule property measuring device described in Patent Document 1 requires manual operation: placing a sample on a measurement plate and then manually moving the measurement plate to align the indenter with the sample. This method presents a problem in that it is difficult to efficiently test a large number of samples. Furthermore, the microcompression testing machine described in Patent Document 2 can automatically repeat tests on multiple samples, but requires three stages, which can make the mechanism complicated. Furthermore, when the lower platen on which the sample is placed is moved horizontally or vertically, the sample may move, making alignment difficult.

[0007] The present invention has been made in light of the above circumstances, and has as its object to make it possible to efficiently test a large number of samples without making the mechanism of the testing device as complicated as possible. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the microparticle compression test device of the present invention is a microparticle compression test device capable of compressing microparticles to test their compression characteristics, and comprises: a sample placement area having a depth and width in a horizontal plane, in which a plurality of microparticles to be used as samples can be placed on the sample placement area; an imaging unit that can image the sample placed on the sample placement area in the depth direction of the sample placement area; an image processing unit that obtains image information of the sample from the imaging unit, selects the sample to be tested, and determines the position of the selected sample in the width direction of the sample placement area; an indenter that is provided above the sample placement area and has a flat bottom; and a movable indenter that holds the indenter and is movable in the width direction and is movable relative to the sample placement area. a compression mechanism section that can move in the vertical direction relative to the image pickup section, the image processing section, the compression mechanism section, and the analysis section that can apply a test force to the selected sample to compress it and determine the value of the test force and the vertical displacement from the upper surface of the sample placement area to the bottom surface of the indenter when the indenter is moved to a position directly above the selected sample in the width direction obtained from the image processing section to align it with the selected sample and bring the bottom surface into close contact with the selected sample in the vertical direction; an analysis section that can analyze the compression characteristics of the selected sample based on the test force value and displacement determined by the compression mechanism section; and a control section that is connected to each of the imaging section, the image processing section, the compression mechanism section, and the analysis section and can control the operation of each of the sections.

[0009] In order to solve the above-mentioned problems, the microparticle compression testing method of the present invention is a microparticle compression testing method that uses a testing device to compress microparticles and test their compression characteristics, in which a plurality of microparticles to be used as samples are placed in a sample placement area of ​​the testing device, which has a depth and width in a horizontal plane, the placed sample is imaged in the depth direction of the sample placement area, image information of the imaged sample is obtained to select the sample to be tested, and the position of the selected sample in the width direction of the sample placement area is determined, an indenter with a flat bottom surface that is located above the sample placement area in the testing device is moved to just above the determined position in the width direction of the sample placement area of ​​the selected sample, thereby aligning it with the selected sample and abutting the bottom surface closely in the vertical direction, applying a test force to the selected sample to compress it, and determining the value of the test force and the vertical displacement from the top surface of the sample placement area to the bottom surface of the indenter, and analyzing the compression characteristics of the selected sample based on the value of the test force and the displacement. [Effects of the Invention]

[0010] The microparticle compression testing device and microparticle compression testing method of the present invention determine the widthwise position of a sample placed in a sample placement area having depth and width, and then move the indenter in that widthwise direction to align it with the sample.This has the advantage of allowing multiple samples distributed in the widthwise direction to be tested efficiently with a relatively simple mechanism, compared to conventional technologies that require manual movement of the measurement substrate for alignment or movement of the lower pressure plate on which the sample is placed using three stages. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing the configuration and structure of a part of a microparticle compression testing device according to an embodiment (Example 1). [Figure 2] Figure 2 is a diagram showing the configuration and structure of the microparticle compression testing device shown in Figure 1, viewed from the right side. (Example 1) [Figure 3] Fig. 3 is a block diagram of the microparticle compression test device shown in Figs. 1 and 2. (Example 1) [Figure 4] Fig. 4 is a flow chart of a compression test of fine particles carried out using the fine particle compression test device shown in Figs. 1 to 3. (Example 1) [Figure 5] 5 is a diagram showing an example of an image of the mounted sample (Example 1). [Figure 6] Fig. 6 is a block diagram of a microparticle compression testing device according to an embodiment (Example 2). [Figure 7] Fig. 7 is a diagram showing the positional relationship between some components of the microparticle compression testing device shown in Fig. 6 (Example 2) [Figure 8] Fig. 8 is a flow chart of a compression test of fine particles carried out using the fine particle compression test device shown in Fig. 6. (Example 2) [Figure 9] Figure 9 is a flow chart illustrating the automated repetition of the compression test shown in Figure 8. (Example 2) [Figure 10] Fig. 10 is a block diagram of a microparticle compression testing device according to an embodiment (Example 3). [Figure 11] Fig. 11 is a flow chart of a microparticle compression test performed using the microparticle compression test device shown in Fig. 10. (Example 3) DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [Example]

[0013] Fig. 1 is a diagram illustrating the configuration and structure of a microparticle compression testing device 100 according to Example 1 of the present invention (excluding some components). The main components of the microparticle compression testing device 100 are fixed to the upper surface of a base 101. The four peripheral sides of the base 101 (front, left side, back, and right side) are defined as shown in parentheses in Fig. 1.

[0014] The hexagonal prism-shaped structure located near the center of Figure 1, with a partially enlarged view shown in the upper right corner, is the sample placement section 102. A sample placement area 103 is provided on the elongated surface located at the top of the hexagonal prism's side surface. While the sample placement area 103 refers to the entire uppermost side surface of the hexagonal prism in Figure 1, it may also refer to a portion of the uppermost side surface. As shown in the partially enlarged view, the direction parallel to the generatrix of the hexagonal prism is the width of the sample placement area 103, and the direction parallel to one side of the base of the hexagonal prism is the depth of the sample placement area 103 (width > depth). Hereinafter, the width and depth directions of the sample placement area 103 are referred to as the X and Y directions, respectively. The vertical direction is referred to as the Z direction.

[0015] The rectangular prism is placed horizontally, and the elongated area on the side of the topmost part is designated as the sample placement area 103 in order to prevent the scattered samples from lining up in the Y direction as much as possible (samples scattered outside the sample placement area 103 will fall off), and to ensure that they are lined up in a row in the X direction as much as possible. As long as the shape is suitable for this purpose, it does not have to be a hexagonal prism, and it does not even have to be a rectangular prism (for example, it can be a shape in which part of the side of a cylinder is cut off parallel to the generatrix).

[0016] The enlarged partial view of Figure 1 shows a state in which a single microparticle (particle diameter 1 mm or less) sample (shown by the shaded circle) is placed in the sample placement area 103. Above the microparticle is an indenter 104, a component of the microparticle compression testing device 100. The indenter 104 is a high-hardness, pin-shaped member with a flat bottom, such as, but not limited to, a core pin. As will be described shortly, the indenter 104 can be moved in the X and Z directions indicated by the block arrows in the enlarged partial view.

[0017] By appropriately selecting the depth dimension of the sample placement area 103 in accordance with the particle diameter distribution of the multiple microparticles to be tested, it is possible to expect a higher probability of multiple samples dispersed in the sample placement area 103 being placed in a single row in the X direction. To place and compress microparticles, the depth must be equal to or greater than the particle diameter. However, if the depth is too large, there is a problem of multiple particles being placed side-by-side in the depth direction. Based on experience, this problem can be largely ignored if the depth is 10d or less, where d is the median particle diameter of the multiple microparticles used as samples. Therefore, in Example 1, the depth dimension is set to a value between d and 10d. Furthermore, if the diameter of the bottom surface of the indenter is too small, particles placed off-center in the depth direction of the sample placement area may not be compressed properly. However, if the diameter is too large, a large inter-particle distance is required to compress a single particle during compression, reducing efficiency. Therefore, it is preferable that the diameter of the bottom surface of the indenter be equal to or slightly larger than the depth dimension of the sample placement area. For the above reasons, in Example 1, the bottom surface of the indenter 104 is made circular with a diameter slightly larger than the depth dimension of the sample placement area 103 .

[0018] The indenter 104 is supported by an indenter support 105. The indenter support 105 is the part located near the back surface, roughly surrounded by a dashed oval in Figure 1. The indenter support 105 is mounted on a stage 106 located immediately behind and below it, and the indenter 104 is held to the stage 106 via the indenter support 105. The stage 106 is driven by a motor driver (not shown), which can move the indenter 104 in the X and Z directions. Note that the sample placement unit 102 and the indenter 104 can be connected to the ground side of the device power supply (not shown) to prevent phenomena such as the attraction or popping out of the sample due to static electricity.

[0019] When the stage 106 is driven vertically to lower the indenter 104 vertically, the bottom surface of the indenter 104 comes into contact with the sample placed in the sample placement area 103, and further test force can be applied to compress the sample. At this time, the displacement (the distance in the Z direction between the bottom surface of the indenter 104 and the top surface of the sample placement area 103), which is one of the parameters in the compression test, can be determined from the level of descent of the stage 106 in the Z direction. The displacement may be measured using a separately provided displacement sensor, or may be calculated from an image of the particle compression captured by an imaging device. Note that instead of lowering the indenter 104, the sample placement section 102 may be raised.

[0020] A test force measuring unit 107 is provided below the sample placement unit 102. The test force measuring unit 107 is composed of, for example, a load cell, and can detect the test force, which is another parameter in a compression test. The test force measuring unit 107 of the indenter 104 is not limited to a load cell, and for example, an electromagnetic force balance type electronic balance can also be used. The test force measuring unit 107 can also be provided above the indenter 104.

[0021] The configuration and structure of the microparticle compression testing device 100 will be described from a different angle (from the right side in FIG. 1) with reference to FIG. 2. In FIG. 2, the left-right direction is the Y direction, and the direction perpendicular to the paper surface is the X direction.

[0022] In FIG. 2, the components denoted by reference numerals 101 to 107 are identical to the components denoted by the same reference numerals in FIG. 1. Furthermore, an imaging unit 108 (not shown in FIG. 1) is located to the left of the top of the sample placement unit 102 (the sample placement area 103, the reference numeral omitted in FIG. 2). Mechanical holding members and the like are omitted. The imaging unit 108 can capture images of the sample placed in the sample placement area 103 in the Y direction (indicated by a block arrow pointing right). The X-direction field of view of the imaging unit 108 covers a certain range within the width of the sample placement area 103, and the Z-direction field of view is wide enough to capture the process of compressing the sample by lowering the indenter 104. The contrast of the image can be enhanced by providing a backlight 109 behind the sample as seen from the imaging unit 108.

[0023] The indenter 104 is supported at the lower left position of the indenter support part 105 in Fig. 2. As described above, the indenter support part 105 is mounted on the stage 106. The stage 106 is driven by a motor driver (not shown), and can move the indenter 104 in the X and Z directions via the indenter support part 105.

[0024] The configuration of the microparticle compression testing device 100 will be explained again with reference to the block diagram of Fig. 3. In Fig. 3, the components designated by reference numerals 101 to 108 are the same as the components designated by the same reference numerals in Figs. 1 and 2. In addition to the components described above, the microparticle compression testing device 100 also includes a motor driver 110, an image processing unit 121, a control unit 122, and an analysis unit 123. The image processing unit 121, the control unit 122, and the analysis unit 123 may each be a functional block implemented in a microprocessor built into the microparticle compression testing device 100 or an external personal computer. The control unit 122 is connected to a display unit and an operation unit (not shown) as a human interface.

[0025] The image processing unit 121 processes the image of the sample captured by the imaging unit 108 and can send information on the shape and position in the X direction of the sample placed on the sample placement area 103 to the control unit 122. The control unit 122 controls the motor driver 110 to drive the stage 106 in the X direction, thereby moving (aligning) the indenter 104 to a position directly above in the X direction the sample selected as the test subject. The control unit 122 controls the motor driver 110 to drive the stage 106 downward in the Z direction (compression instruction), thereby pressing the indenter 104 against the sample to compress it.

[0026] When the sample is compressed, the stage 106 can send information about the level of descent in the Z direction (this can be expressed as the displacement described above) to the control unit 122. In addition, the test force measurement unit 107 can send the detected test force value to the control unit 122. The control unit 122 can send the displacement and test force values ​​to the analysis unit 123, allowing the analysis unit 123 to analyze the compression characteristics of the sample.

[0027] The indenter support unit 105, stage 106, test force measurement unit 107, and motor driver 110, which are enclosed in a dashed frame in Figure 3, work in coordination to perform a series of operations from positioning the indenter 104 to compressing the sample and detecting the test force, and are therefore collectively positioned as a compression mechanism unit 115.

[0028] 4, a microparticle compression test performed using the microparticle compression test device 100 will be described. First, a plurality of microparticles (particle diameter 1 mm or less) to be used as samples are scattered and placed on the sample placement area 103 (step S401, which may be performed manually or automatically as described in Example 2). Because the sample placement area 103 has an elongated shape, samples scattered outside the sample placement area 103 will fall off and not remain in the sample placement area 103, and samples remaining in the sample placement area 103 can be expected to line up in a row in the X direction with a high probability.

[0029] Next, the image capturing unit 108 is used to capture an image of the placed sample in the Y direction (step S402). An example of the captured image is shown in Fig. 5. The image information shown in Fig. 5 is binarized, and shows the sample placement unit 102 at the bottom, five samples lined up thereon, and the indenter 104 located at the top, with the backlight 109 as the background.

[0030] The image processing unit 121 cuts out the portion of the binary image in which the sample is captured, and uses known image processing techniques to determine the position of each sample in the X direction and indexes representing the shape, such as particle size, roundness, aspect ratio, unevenness, and symmetry. The control unit 122 obtains information on the position and each index for each sample from the image processing unit 121, and can select an appropriate sample as a test subject, one in which there is no aggregation between samples and the distance between adjacent samples is ensured (step S403).

[0031] The control unit 122 sends position information in the X direction of the sample selected as the test subject to the motor driver 110, drives the stage 106 in the X direction to move the indenter support unit 105, and aligns the indenter 104 with a position directly above the sample to be tested in the X direction (step S404). Subsequently, the control unit 122 sends a compression command to the motor driver 110, drives the stage 106 downward in the Z direction, and brings the bottom surface of the indenter 104 into contact with the sample to be tested, thereby compressing the sample (step S405).

[0032] The control unit 122 obtains information on the level of descent in the Z direction from the stage 106 when the sample is compressed and converts it into a displacement of the indenter 104, and can also obtain information on the test force applied to the sample from the test force measurement unit 107. The control unit 122 sends this information to the analysis unit 123, which can use known analysis techniques to analyze the crushing strength of the sample, the rate of change in displacement (relative to particle size ratio) while the test force is maintained after the sample is crushed, and the like (step S406). The control unit 122 can obtain these analysis results from the analysis unit 123 and display them on a connected display unit.

[0033] As described above, according to the microparticle compression testing device 100 of Example 1 of the present invention, alignment is performed by moving the indenter in one dimension rather than the sample stage, which allows alignment with a simpler mechanism than the conventional method of driving the sample stage in two dimensions, and also prevents the sample from moving and changing its position while the sample stage is being moved. [Example]

[0034] Fig. 6 is a block diagram of a microparticle compression testing device 200 according to a second embodiment of the present invention. In addition to the components of the microparticle compression testing device 100 of the first embodiment shown in Fig. 3 (each component in Fig. 6 is given the same reference numerals as in Fig. 3), the microparticle compression testing device 200 is equipped with a cleaning unit 201 and a sample supply unit 205. Fig. 7 is a diagram illustrating the positional relationship between the sample mounting unit 102 and the indenter 104 and the additional components, namely the cleaning unit 201 and the sample supply unit 205.

[0035] As shown in FIG. 7, the cleaning unit 201 has a cylindrical body and a brush 202 and a brush 203 attached to the top and bottom surfaces of the tip thereof. The longitudinal direction of the cleaning unit 201 coincides with the X direction, and the initial position is when the cleaning unit 201 extends in the X direction (toward the lower left in FIG. 7) across the sample placement area 103 and is raised in the Z direction. The cleaning unit 201 is connected to a drive mechanism (not shown), which can move the cleaning unit 201 in the X direction in response to instructions from the control unit 122. The cleaning unit 201 can move its tip to directly below the indenter 104 and move the brush 202 via the drive mechanism to clean the bottom surface of the indenter 104. The cleaning unit 201 can clean the sample placement area 103 by moving the brush 203 via the drive mechanism while moving its tip along the X direction (the width direction of the sample placement area 103). Note that the brushes 202 and 203 may be integrated into one unit.

[0036] As shown in FIG. 7, the sample supply unit 205 is configured by attaching a vibrator 206 to the bottom surface of a groove-shaped member with a V-shaped cross section, and attaching a mesh filter 207 to one end of the groove (the left end in FIG. 7). The longitudinal direction of the sample supply unit 205 coincides with the X direction, and the initial position is the position where the sample placement area 103 is extended in the X direction (upper right in FIG. 6) and raised in the Z direction. The sample supply unit 205 is connected to a drive mechanism (not shown), which can move the sample supply unit 205 in the X direction in response to instructions from the control unit 122. The sample supply unit 205 may also include a mechanism (not shown) that can appropriately supply sample microparticles into the groove from the right end of the groove in FIG. 7. The cross section of the groove may be a V-shape, a downwardly convex U-shape, a bathtub curve, or other known powder supply devices (e.g., a screw feeder type) rather than the vibrating feeder type described above. The mesh filter 207 has the effects of removing coarse particles, increasing the distance between dispersed particles, and eliminating particle aggregation.

[0037] 6, 7, and 8, a microparticle compression test performed using the microparticle compression test device 200 will be described. First, in response to an instruction from the control unit 122, the cleaning unit 201 is moved in the X direction from its initial position toward the sample placement unit 102, and the brush 203 is moved to clean the sample placement area 103, and the brush 202 is also moved to clean the bottom surface of the indenter 104 (step S801). This cleaning allows initialization to a state in which neither the sample placement area 103 nor the indenter 104 is present.

[0038] After step S801 is completed, the control unit 122 retreats the cleaning unit 201 to its initial position. Next, the control unit 122 instructs the sample supply unit 205 to move in the X direction from its initial position toward the sample placement unit 102, vibrating the oscillator 206 and sieving the sample provided inside the groove from the left end in Fig. 7. The sieved-out sample is sorted by particle size through a mesh filter 207 and then dispersed and placed on the sample placement area 103 (step S802).

[0039] After step S802 is completed, the control unit 122 retreats the sample supply unit 205 to its initial position. The processes of steps S803 to S807 following step S802 are the same as the processes of steps S402 to S406 in Fig. 4, respectively, and therefore will not be described here.

[0040] With reference to the flowchart in Fig. 9, the automatic repetition of a microparticle compression test performed using the microparticle compression test device 200 will be described. The processes of steps S901 to S903 in Fig. 9 are the same as the processes of steps S801 to S803 in Fig. 8, respectively. It is assumed that the number of samples that the control unit 122 has determined to be appropriate as test subjects based on the information obtained from the image processing unit 121 is N (step S904). In the following description, it is assumed that N≧2.

[0041] The processing for the kth (1≦k≦N) sample out of the total N samples is as shown in steps S905 to S910 below. First, k is set to 1 (step S905). The subsequent steps S906 to S908 are the same as steps S805 to S807 in FIG. 8, respectively.

[0042] If k≦N−1 (YES in step S909), the control unit 122 determines that there are untested samples selected as test targets. Next, the control unit 122 moves the indenter 104 to the position of the brush 202 and cleans the bottom surface (step S910). The control unit 122 then adds 1 to the value of k (step S911), returns to step S906, and executes processing on the (k+1)th sample.

[0043] If k≦N−1 is not satisfied in step S909 ("NO" in step S909), the control unit 122 determines that testing of all N samples has been completed in the previous step S908. Next, the control unit 122 drives the cleaning unit 201 to clean the bottom surface of the indenter 104 with the brush 202 and the sample placement area 103 with the brush 203, thereby initializing to a state where no sample is present and completing the processing for all N samples. The control unit 122 may then supply the next sample to be tested to the sample supply unit 205 and repeat the processing from step S902 onwards.

[0044] As described above, according to the microparticle compression testing device 200 of Example 2 of the present invention, the bottom surface of the indenter and the sample placement area can be automatically cleaned before, during, and after the compression test, thereby providing the additional benefit of automatically repeating compression tests on multiple target samples to improve work efficiency. [Example]

[0045] Figure 10 is a block diagram of a microparticle compression testing apparatus 300 according to Example 3 of the present invention. The microparticle compression testing apparatus 300 has a compression mechanism unit 315 instead of the compression mechanism unit 115 of the microparticle compression testing apparatus 200 shown in Figure 6. The microparticle compression testing apparatus 300 has a control unit 322 instead of the control unit 122 of the microparticle compression testing apparatus 200 shown in Figure 6. In addition, the sample mounting unit 102 (the upward-facing side is the sample mounting area 103), indenter 104, imaging unit 108, image processing unit 121, analysis unit 123, cleaning unit 201, and sample supply unit 205 provided in the microparticle compression testing apparatus 300 have the same configurations as those shown in Figure 6 with the same reference numerals.

[0046] The compression mechanism 315 is equipped with a load generating unit 301 and a displacement sensor 302 at a location corresponding to the indenter support unit 105 of the microparticle compression testing device 200. The compression mechanism 315 is equipped with an elevator unit 303 at a location corresponding to the test force measuring unit 107 of the microparticle compression testing device 200. In addition, the stage 106 and motor driver 110 of the compression mechanism 315 are the same as those shown in FIG. 6 with the same reference numerals. The positional relationships between the compression mechanism 315 and the same components as those shown in FIG. 6, as well as the definitions of the X, Y, and Z directions, are the same as the positional relationships between the subordinate components and components of the compression mechanism 115 shown in FIGS. 1 and 2, respectively.

[0047] The load generating unit 301 applies an electromagnetic force generated by passing a test current through a coil placed in a magnetic field to the sample via the indenter 104 as a test force (a known electromagnetic force loading method). The displacement sensor 302 is provided near the indenter 104 and can measure the displacement between the top surface of the sample placement area 103 and the bottom surface of the indenter 104, for example, by a known differential transformer method. The lifting unit 303 manually or automatically lifts and lowers the sample placement unit 102 to adjust its vertical position, and can fix the selected sample between the bottom surface of the indenter 104 and the top surface of the sample placement area 103.

[0048] A microparticle compression test performed using the microparticle compression test device 300 will be described with reference to the flowchart of Fig. 11. The processes of steps S1101 to S1105 in Fig. 11 are the same as the processes of steps S801 to S805 in Fig. 8, respectively.

[0049] After aligning the indenter 104 in the X direction with respect to the sample to be tested in step S1105, the position of the sample mounting part 102 in the Z direction can be adjusted using the elevator part 303, the stage 106, or both, to fix the sample between the bottom surface of the indenter 104 and the upper surface of the sample mounting area 103 (step S1106). This step may be performed manually, or automatically by providing a known optical means or a means for detecting changes in the descending speed of the indenter.

[0050] Next, the control unit 322 sets the value of the test force to be applied to the sample from the indenter 104 and instructs the load generating unit 301. The load generating unit 301 applies an electromagnetic force to the sample via the indenter 104 by passing a test current corresponding to the instructed test force through a coil. At this time, the displacement sensor 302 measures the displacement caused by the instructed test force and sends the data to the control unit 322 (step S1107). The subsequent processing of step S1108 is the same as the processing of step S807 in FIG. 8, except that the control unit 322 sets the value of the test force in advance.

[0051] As described above, the microparticle compression testing device 300 according to the third embodiment of the present invention can demonstrate the advantages of a simple mechanism that moves the indenter in one dimension to align the position rather than the sample stage, even in a microparticle compression test that employs an electromagnetic force loading method used for low load loading. [Example]

[0052] The application range of the technique of placing a sample consisting of multiple microparticles in a sample placement area whose width is greater than its depth as in Example 1 and moving the operating or observation means in the width direction of the sample placement area to align it with each sample is not limited to compression tests. For example, the following device can be considered.

[0053] A microparticle characteristic testing device capable of observing or manipulating microparticles to test their characteristics, a sample placement section having a sample placement area having a depth and a width in a horizontal plane, and capable of placing a plurality of microparticles as samples in the sample placement area; an imaging unit capable of imaging the sample placed in the sample placement area in the depth direction of the sample placement area; an image processing unit that obtains image information of the sample from the imaging unit, selects a sample to be tested, and determines the position of the selected sample in the width direction of the sample placement area; a sample detection unit provided above the sample placement area and capable of observing or manipulating the selected sample; an alignment mechanism that holds the sample detection unit and moves it in the width direction, thereby moving the sample detection unit to a position directly above the selected sample obtained from the image processing unit in the width direction and aligning it with the selected sample; an analysis unit that receives information obtained by observing or manipulating the selected and aligned sample from the sample detection unit and analyzes the characteristics of the selected and aligned sample; a control unit connected to each of the imaging unit, the image processing unit, the sample detection unit, the alignment mechanism unit, and the analysis unit, and capable of controlling the operation of each of the units; It is possible to envisage a microparticle characteristic testing device (1) characterized by comprising:

[0054] The above-mentioned microparticle characteristic test device (1) further includes a sample supply unit that can supply sample microparticles and scatter and place them in the sample placement area, and a cleaning unit that can clean the sample placement area, and the control unit: and further connecting the cleaning unit to the sample placement area, and causing the cleaning unit to clean the sample placement area before placing microparticles to be used as samples on the sample placement area. Further, the sample supply unit is connected to the sample supply unit, and the sample supplied to the sample supply unit is dispersed and placed in the sample placement area. causing the imaging unit to capture an image of the sample placed in the sample placement area; causing the image processing unit to obtain image information of the captured sample, select a sample to be tested, and determine the position of the selected sample in the width direction of the sample placement range; the alignment mechanism moves the sample detection unit to a position directly above the selected sample in the width direction, and aligns the sample detection unit with the selected sample; causing the sample detection unit to observe or operate the selected sample; The analysis unit receives information obtained by observing or manipulating the selected and aligned sample from the sample detection unit and analyzes the characteristics of the selected and aligned sample. A microparticle characteristic testing device (2) can be envisioned that is capable of:

[0055] In the above-mentioned microparticle characteristic test device (2), When there are a plurality of samples selected in the image processing unit, and the number of selected samples is represented by N, the control unit After analyzing the compression characteristics of each of the first to (N-1)th selected samples, for the next sample, have each of the units determine the position of the selected sample in the width direction, align the sample detection unit with the selected sample, and observe or operate the selected and aligned sample, as well as analyze the characteristics; After analyzing the characteristics of the Nth sample selected, the cleaning unit cleans the sample placement area. A microparticle characteristic testing device (3) can be envisioned that is capable of:

[0056] The sample detection unit in the above-mentioned microparticle characteristic test devices (1) to (3) can be, for example, an electrode or probe capable of measuring the charge amount, conductivity, etc. of a single particle, or a light detection probe capable of measuring the absorbance, absorption spectrum, scattering characteristics, etc. of a single particle (for the latter, the microparticle characteristic test device needs to be equipped with an irradiation light source).

[0057] As described above, according to the microparticle characteristic testing device (1) to (3) of Example 4 of the present invention, a wide range of electrical, optical, and other characteristic tests of microparticles can be efficiently performed by applying a technique of moving the microparticle manipulation or observation means in the width direction of the sample placement area and aligning it with each individual sample. [Explanation of symbols]

[0058] 100, 200, 300 Microparticle Compression Test Equipment 101 Foundation 102 Sample placement section 103 Sample placement range 104 Indenter 105 Indenter support part 106 Stages 107 Test force measurement unit 108 Imaging unit 109 Backlight 110 Motor Driver 115, 315 Compression mechanism 121 Image processing section 122, 322 Control section 123 Analysis Department 201 Cleaning Department 202, 203 Brush 205 Sample Supply Unit 206 Oscillator 207 Mesh filter 301 Load generating part 302 Displacement Sensor 303 Lifting section

Claims

1. A microparticle compression testing device capable of compressing microparticles and testing their compression characteristics, a sample placement section having a sample placement area having a depth and a width in a horizontal plane, and capable of placing a plurality of microparticles as samples in the sample placement area; an imaging unit capable of imaging the sample placed in the sample placement area in the depth direction of the sample placement area; an image processing unit that obtains image information of the sample from the imaging unit, selects a sample to be tested, and determines the position of the selected sample in the width direction of the sample placement area; an indenter provided above the sample placement area and having a flat bottom surface; a compression mechanism unit that can hold the indenter and move it in the width direction and move it in the vertical direction relative to the sample placement unit, and that can apply a test force to the selected sample to compress it when the indenter is moved to a position directly above the selected sample in the width direction obtained from the image processing unit to align it with the selected sample and bring the bottom surface into close contact with the selected sample in the vertical direction, and can determine the value of the test force and the vertical displacement from the top surface of the sample placement area to the bottom surface of the indenter; an analysis unit capable of analyzing the compression characteristics of the selected sample based on the test force value and displacement obtained by the compression mechanism unit; a control unit connected to each of the imaging unit, the image processing unit, the compression mechanism unit, and the analysis unit, and capable of controlling the operation of each of the units; A microparticle compression testing device comprising:

2. 2. The microparticle compression testing device according to claim 1, wherein the shape of the sample placement area is a rectangle in which the width is greater than the depth.

3. 3. The microparticle compression testing device according to claim 2, wherein the sample placement portion is shaped like a square pillar having the sample placement area on one of a plurality of sides.

4. A microparticle compression testing device as described in any one of claims 1 to 3, characterized in that the depth of the sample placement area is in the range of d to 10d, where d is the median particle diameter of the multiple microparticles used as the sample, and the bottom surface of the indenter is circular with a diameter greater than or equal to the depth.

5. A microparticle compression testing device as described in any one of claims 1 to 3, characterized in that the compression mechanism section is configured so that at least one of the sample mounting section and the indenter is movable vertically, thereby allowing the indenter to be moved vertically relative to the sample mounting section.

6. the compression mechanism unit includes a stage that holds the indenter and makes it movable in the width direction and vertical direction, and a test force measurement unit that is provided above the indenter or below the sample placement area, and the stage causes the indenter to vertically lower toward the selected sample, applying a test force to the selected sample to compress it, and the value of the applied test force can be determined by the test force measurement unit, The compression mechanism can further determine the vertical displacement from the vertical lowering level of the stage.

4. The microparticle compression testing device according to claim 1, wherein the microparticle compression testing device is a microparticle compression testing device.

7. the compression mechanism section includes a stage that holds the indenter and moves it in the width direction, and an elevator section that adjusts the vertical position of the sample mounting section to fix the selected sample between the bottom surface of the indenter and the upper surface of the sample mounting area, and is capable of compressing the fixed sample by applying an electromagnetic force to the fixed sample using an electromagnetic force loading method, and determining a set value of the electromagnetic force as the value of the test force, The compression mechanism further includes a displacement sensor capable of measuring the displacement between the top surface of the sample placement area and the bottom surface of the indenter, and the measurement value of the displacement sensor can be obtained as the displacement in the vertical direction.

4. The microparticle compression testing device according to claim 1, wherein the microparticle compression testing device is a microparticle compression testing device.

8. A microparticle compression testing device as described in any one of claims 1 to 3, characterized in that it further comprises a sample supply unit that can input sample microparticles and spread and place them on the sample placement area, and a cleaning unit that can clean the bottom surface of the indenter and the sample placement area, and the control unit is further connected to the sample supply unit and the cleaning unit, respectively, and can control the operation of the sample supply unit and the cleaning unit.

9. The microparticle compression testing device described in claim 8, characterized in that the sample supply unit is configured so that microparticles are introduced into one end of a member whose cross section is formed as a downwardly convex groove, and the member is vibrated so that the microparticles can be dispersed from the other end of the member, and a mesh filter can be attached to the other end of the member.

10. The microparticle compression testing device of any one of claims 1 to 3, characterized in that the image processing unit binarizes the image information of the sample obtained from the imaging unit, determines shape characteristics including particle diameter, unevenness and circularity, and position in the width direction, and can select samples to be tested based on the shape characteristics and the distance in the width direction between adjacent samples.

11. The microparticle compression testing device according to any one of claims 1 to 3, characterized in that the analysis unit is capable of analyzing the crushing strength, rate of change, compression rate, and recovery rate as the compression characteristics of the selected sample.

12. The control unit causing the cleaning unit to clean the bottom surface of the indenter and the sample placement area; The sample introduced into the sample supply unit is dispersed and placed in the sample placement area; causing the imaging unit to capture an image of the sample placed in the sample placement area; causing the image processing unit to obtain image information of the captured sample, select a sample to be tested, and determine the position of the selected sample in the width direction of the sample placement range; the compression mechanism moves the indenter to a position directly above the selected sample in the width direction to align it with the selected sample, and vertically approaches the selected sample to bring the bottom surface of the indenter into contact with the selected sample, and applies a test force to the selected sample to compress it, and calculates the value of the test force and the vertical displacement from the top surface of the sample placement area to the bottom surface of the indenter; The analysis unit analyzes the compression characteristics of the selected sample based on the test force and displacement values ​​obtained by the compression mechanism unit.

9. The microparticle compression testing device according to claim 8, wherein the microparticle compression testing device is capable of:

13. When there are a plurality of samples selected in the image processing unit, and the number of selected samples is represented by N, the control unit After analyzing the compression characteristics of each of the first to (N-1)th selected samples, the cleaning unit cleans the bottom surface of the indenter; For the next sample, have each of the units determine the position of the selected sample in the width direction, align and compress the indenter with the selected sample, determine the value of the test force and displacement, and analyze the compression characteristics; After analyzing the compression characteristics of the Nth selected sample, the cleaning unit cleans the bottom surface of the indenter and the sample placement area.

13. The microparticle compression testing device according to claim 12, wherein the microparticle compression testing device is capable of:

14. A microparticle compression testing method for testing compression characteristics by compressing microparticles using a testing device, comprising: A plurality of microparticles to be used as samples are placed in a sample placement area of ​​the test device having a depth and width in a horizontal plane; taking an image of the placed sample in the depth direction of the sample placement range; obtaining image information of the captured sample to select a sample to be tested, and determining the position of the selected sample in the width direction of the sample placement area; an indenter having a flat bottom surface, which is provided above the sample placement range in the testing device, is moved to a position directly above the selected sample in the width direction of the sample placement range determined, thereby aligning the indenter with the selected sample and bringing the bottom surface into close contact with the selected sample in the vertical direction; a test force is applied to the selected sample to compress it, and a value of the test force and a vertical displacement from the top surface of the sample placement area to the bottom surface of the indenter are obtained; Analyzing the compressive properties of the selected sample based on the test force value and displacement. A method for testing microparticles in compression.

15. cleaning the sample placement area and the bottom surface of the indenter before placing the microparticles to be used as samples in the sample placement area; In a case where there are a plurality of selected samples, where the number of selected samples is represented by N, cleaning the bottom surface of the indenter after analyzing the compression characteristics of each of the first to (N-1)th selected samples; For a next sample, perform the steps of determining the position in the width direction of the selected sample, aligning and compressing the indenter with the selected sample, determining the test force value and displacement, and analyzing the compression characteristics; After analyzing the compression characteristics of the Nth selected sample, the bottom surface of the indenter and the sample placement area are cleaned.

15. The method for testing microparticles in compression according to claim 14.

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