Method for evaluating pressing test device

Abstract

To provide a method for evaluating a pressing test device that allows evaluation of linearity of a load cell, while an operator avoids the annoyance of placing a plate-like object for inspection, and while an indenter avoids pressing the hard plate-like object for inspection, in a method for evaluating a pressing test device for evaluating whether a pressing test device for measuring intensity of a test piece is operating normally.SOLUTION: A method for evaluating a pressing test device includes: a preparation step 1001 for preparing a pressing test device; a moving step 1002 for causing an indenter unit to move and approach a support unit side at a constant velocity using a moving unit, in a state that a test piece is not supported by the support unit; a measuring step 1003 for measuring a load to be pressed by the indenter unit when a base of the indenter unit contacts the support unit, by using a load cell; and an evaluation step 1004 for evaluating a state of the pressing test device on the basis of the load acquired in the measuring step 1003.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for evaluating a press test device for measuring the strength of a test piece. [Background technology]

[0002] A three-point bending test defined in SEMI (Semiconductor Equipment and Materials International) standard G86-0303 is commonly used as a method for measuring the strength (transverse strength, bending strength) of a test piece (chip) made of a chip cut from a semiconductor wafer, and for example, a press tester for accurately measuring a fracture toughness value known as the JIC value has been disclosed (see, for example, Patent Document 1). Such press tester is equipped with a load cell that measures the load with which an indenter presses the test piece, and measures the load applied when the indenter presses the test piece until the test piece breaks. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-017054 Summary of the Invention [Problem to be solved by the invention]

[0004] Before conducting an actual pressurization test, it is sometimes necessary to evaluate whether the pressurization test device is operating normally. For example, this can be done by evaluating whether the linearity of the load cell is within a predetermined threshold. To perform this evaluation, a hard test plate that does not bend when pressed by an indenter is placed on the support portion of the support unit. The load change caused by the indenter pressing against the test plate is then acquired to evaluate the linearity of the load cell. However, this evaluation method has problems, such as the inconvenience of the operator having to place the test plate and the risk of scratching or chipping the tip of the indenter when pressing against the hard test plate.

[0005] The present invention has been made in consideration of the above problems, and its purpose is to provide a method for evaluating a pressing test device that evaluates whether the pressing test device, which measures the strength of a test piece, is operating normally, which can evaluate the linearity of a load cell while avoiding the hassle of the operator having to place a test plate and preventing the indenter from pressing against a hard test plate. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the evaluation method for a pressurization tester of the present invention includes a support unit having a pair of support parts extending parallel to each other with a gap therebetween and supporting the underside of a test piece, an indenter unit arranged above the support unit and between the pair of support parts, the indenter unit being composed of a base and an indenter erected from approximately the center of the base and pressing the test piece supported by the support unit, a moving unit that moves the indenter unit relatively close to the test piece supported by the support unit, and a moving unit that moves the indenter unit so that the indenter of the indenter unit is pressed against the support unit. a moving step in which the moving unit moves the indenter unit toward the support unit at a constant speed while the support unit is not supporting the test piece; a measuring step in which the base of the indenter unit comes into contact with the support unit and the load applied by the indenter unit is measured with the load cell; and an evaluation step in which the state of the indenter unit is evaluated based on the load obtained in the measuring step.

[0007] The measuring step may include measuring, with the load cell, the load applied by the indenter unit when the base of the indenter unit comes into contact with the upper surfaces of the pair of support parts of the support unit. [Effects of the Invention]

[0008] In the present invention, when the test piece is not supported by the support unit, the moving unit moves the indenter unit closer to the support unit at a constant speed until the base of the indenter unit comes into contact with the support unit, and the load applied by the indenter unit is measured by the load cell.Based on this acquired load, the state of the pressing test device (the state of the linearity of the load cell) is evaluated.This avoids the hassle of the operator having to place a test plate and prevents the indenter from pressing against a hard test plate, while allowing the linearity of the load cell to be evaluated. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a flowchart showing the processing steps of the evaluation method for the press test device according to the first embodiment. [Figure 2] FIG. 2 is a perspective view of a test piece to be tested by the compression test apparatus for carrying out the evaluation method for the compression test apparatus according to the first embodiment. [Figure 3] FIG. 3 is a perspective view showing an example of the configuration of a compression test device for carrying out the evaluation method for a compression test device according to the first embodiment. [Figure 4] FIG. 4 is a perspective view showing a support unit of a compression test apparatus for carrying out the evaluation method for a compression test apparatus according to the first embodiment. [Figure 5] FIG. 5 is a perspective view showing a partial configuration of a compression test apparatus for carrying out the evaluation method for a compression test apparatus according to the first embodiment. [Figure 6] FIG. 6 is a cross-sectional view showing the configuration of a portion of a compression test apparatus for carrying out the evaluation method for a compression test apparatus according to the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view illustrating the measurement step of FIG. [Figure 8] FIG. 8 is a graph illustrating the evaluation steps of FIG. [Figure 9] FIG. 9 is a cross-sectional view illustrating a measurement step of the evaluation method of the pressing test device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the configuration can be made within the scope of the gist of the present invention.

[0011] [Embodiment 1] The evaluation method for a compression test apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart showing the processing steps of the evaluation method for a compression test apparatus according to the first embodiment. FIG. 2 is a perspective view of a test piece 100 that is the test target of a compression test apparatus 1 that implements the evaluation method for a compression test apparatus according to the first embodiment. FIG. 3 is a perspective view showing an example of the configuration of a compression test apparatus 1 that implements the evaluation method for a compression test apparatus according to the first embodiment. FIG. 4 is a perspective view showing a support unit 10 of a compression test apparatus 1 that implements the evaluation method for a compression test apparatus according to the first embodiment. FIG. 5 is a perspective view showing the configuration of a portion of a compression test apparatus 1 that implements the evaluation method for a compression test apparatus according to the first embodiment. FIG. 6 is a cross-sectional view showing the configuration of a portion of a compression test apparatus 1 that implements the evaluation method for a compression test apparatus according to the first embodiment.

[0012] As shown in Fig. 1, the evaluation method for the press test apparatus according to the first embodiment includes a preparation step 1001, a movement step 1002, a measurement step 1003, and an evaluation step 1004. The evaluation method for the press test apparatus according to the first embodiment is an example of the operation process of the press test apparatus 1 shown in Fig. 3 that measures the strength (transverse strength, bending strength) of the test piece 100 (test piece) shown in Fig. 2, and is a method for evaluating the press test apparatus 1. The evaluation method for the press test apparatus according to the first embodiment is performed, for example, to evaluate whether any problems have occurred in the load cell 40 before a destructive test (pressure test) is performed in which the test piece 100 supported by the support unit 10 is pressed with the indenter 22 to destroy it.

[0013] In the first embodiment, the test piece 100, which is the test subject of the press test apparatus 1 for implementing the evaluation method for the press test apparatus according to the first embodiment, is formed, for example, in a flat, rectangular shape, as shown in FIG. 2 . The test piece 100 is obtained by cutting and dividing a wafer, such as a disk-shaped semiconductor device wafer or an optical device wafer, made of a base material such as silicon, sapphire, silicon carbide (SiC), or gallium arsenide, along a plurality of planned division lines formed in a grid pattern on the surface of the wafer, and then dividing the devices formed in the areas defined by the plurality of planned division lines into individual chips. Thus, in the first embodiment, the test piece 100 includes a portion of the wafer and a device, and the device is formed on the front surface of the wafer. However, the present invention is not limited to this, and the test piece 100 may include only a portion of the wafer, with no device formed on the front surface of the wafer.

[0014] As shown in Fig. 3, a compression test apparatus 1 for carrying out the evaluation method for a compression test apparatus according to the first embodiment includes a support unit 10, an indenter unit 20, a moving unit 30, a load cell 40, and a control unit 50. The compression test apparatus 1 shown in Fig. 3 is an apparatus for breaking a test piece 100 shown in Fig. 2 and measuring the strength (transverse strength and bending strength) of the test piece 100.

[0015] The support unit 10 supports the test piece 100 and includes a pair of support bases 11, a pair of support parts 12, a contact member 13, and a support base moving mechanism 14, as shown in FIG. 4. The pair of support bases 11 are each formed in a rectangular parallelepiped shape and are arranged spaced apart from each other so that a predetermined interval 15 (gap) is provided between the pair of support bases 11. In the example of embodiment 1 shown in FIG. 4, the pair of support bases 11 are arranged such that the directions in which one and the other pair of sides of the rectangular parallelepiped shape that are parallel to the horizontal direction extend are along the Y-axis direction and the X-axis direction, respectively, as shown in FIG. 4, and such that the direction in which the predetermined interval 15 is formed is parallel to the X-axis direction and the direction in which the predetermined interval 15 extends is parallel to the Y-axis direction.

[0016] As shown in FIG. 4, each of the pair of support bases 11 has a pair of columnar (rod-shaped) support portions 12 formed on adjacent edges of the upper surface thereof, extending along the Y-axis direction and protruding upward to support the back surface 102, which is the underside of the test piece 100, and the upper surface other than the aforementioned edges is covered with a contact member 13. In this way, the support unit 10 has a pair of support portions 12 that extend parallel to each other with a predetermined distance 15 between them and support the underside of the test piece 100. Each of the pair of support portions 12 is formed of a metal such as stainless steel. In the first embodiment, the cross-sectional shape of the upper surfaces of the pair of support portions 12 is formed into an upwardly convex curved surface.

[0017] The contact member 13 is made of a material (for example, sponge rubber) that is more flexible than the pair of support parts 12, and is formed in a plate shape with a constant thickness. As shown in Figures 4 and 6, the contact member 13 is formed in a rectangular planar shape, and its thickness in an undeformed state is greater than the amount by which the pair of support parts 12 protrude from the upper surfaces of the pair of support bases 11.

[0018] The contact member 13 supports the test piece 100 with the back surface 102 of the test piece 100 placed on its upper surface. For this reason, the upper surface of the contact member 13 supports the back surface 102 of the test piece 100. In the first embodiment, the upper surface of the contact member 13 in an undeformed state is positioned approximately 1 mm above the upper ends of the pair of support portions 12. For this reason, the back surface 102 of the test piece 100 placed on the pair of support bases 11 contacts the upper surface of the contact member 13 with a gap between it and the pair of support portions 12. Furthermore, when the indenter 22 (see FIGS. 3, 5, 6, etc.) presses the test piece 100, the contact member 13 deforms and comes into contact with the back surface 102 of the test piece 100, supporting the back surface 102.

[0019] In addition, if the back surface 102 of the test specimen 100 comes into contact with the pair of supports 12 when placing the test specimen 100 on the pair of support bases 11, the back surface 102 of the test specimen 100 may be damaged by the impact during placement. In this case, the flexural strength of the test specimen 100 may change, making it difficult to measure the flexural strength of multiple test specimens 100 under the same conditions. For this reason, as shown in FIGS. 4 and 6 , the press test apparatus 1 according to embodiment 1 is provided with contact members 13 made of a flexible material on the upper surfaces of the pair of support bases 11 of the support unit 10, and the upper surfaces of the contact members 13 are positioned above the upper ends of the pair of supports 12. For this reason, in the press test apparatus 1 according to embodiment 1, when the test specimen 100 is placed on the pair of support bases 11, the test specimen 100 comes into contact with the upper surfaces of the contact members 13 without coming into contact with the pair of supports 12, and is supported by the upper surfaces. As a result, the compression testing apparatus 1 of embodiment 1 can prevent the back surface 102 of the test piece 100 from coming into contact with the pair of support parts 12 and being damaged when the test piece 100 is placed, and can suppress changes in the flexural strength of the test piece 100.

[0020] The support base moving mechanism 14 moves each of the pair of support bases 11 along the X-axis direction, and by moving each of the pair of support bases 11, changes the predetermined gap 15 between the pair of support bases 11, i.e., the predetermined gap 15 between the pair of support parts 12. The support base moving mechanism 14 is configured to include, for example, a well-known ball screw that is rotatable about an axis along the X-axis direction, a well-known pulse motor that rotates the ball screw about the axis, and well-known guide rails that support each of the pair of support bases 11 so that it is movably in the X-axis direction.

[0021] The indenter unit 20 includes a base 21 and an indenter 22. The base 21 is formed in a generally gate-like shape when viewed from the front, and the indenter 22, which presses the test piece 100 supported by a pair of support stands 11, is fixed between a pair of opposing clamping surfaces and protrudes downward from approximately the center of the base 21 in the X-axis direction. The indenter 22 presses the test piece 100 supported by the support unit 10 to perform a destructive test (compression test). Thus, the indenter unit 20 is composed of the base 21 and the indenter 22, which stands upright from approximately the center of the base 21 and presses the test piece 100 supported by the support unit 10.

[0022] 3, 5, and 6, the indenter 22 presses the test piece 100 supported by the support unit 10 to perform a three-point bending test, but the present invention is not limited to this and may also be configured to perform a four-point bending test, etc. The indenter 22 is disposed above the pair of support bases 11 and above the space between the pair of support parts 12, and extends in the direction in which the pair of support parts 12 extend (Y-axis direction).

[0023] As shown in FIGS. 3, 5, and 6, the indenter 22 is formed as a tapered, integral plate whose width 25 in the X-axis direction narrows downward, and whose lower end is formed as a downwardly convex curved surface. As shown in FIGS. 3 and 5, the lower end of the indenter 22 extends in the Y-axis direction. The lower end of the indenter 22 abuts against and presses against a surface 101, which is the upper surface of the test piece 100 supported on a pair of support bases 11 of the support unit 10. As shown in FIG. 5, the upper end of the indenter 22 is supported by the base 21 parallel to the Y-axis direction, and the lower end is disposed above and between the pair of support parts 12. The lower end of the indenter 22 faces a predetermined distance 15 between the pair of support parts 12 along the Z-axis direction, which is the vertical direction. In addition, in the first embodiment, the length in the Y-axis direction of the pair of support bases 11 (the pair of support parts 12 and the contact member 13) is approximately equal to the length in the Y-axis direction of the indenter 22 (the lower end).

[0024] In the first embodiment, the base 21 has a lower surface 23 parallel to the horizontal plane formed on the lower side from which the indenter 22 protrudes. Like the indenter 22, the (lower surface 23 of) the base 21 extends in the Y-axis direction, as shown in FIGS. 3 and 5 . In the first embodiment, the length of the (lower surface 23 of) the base 21 in the Y-axis direction is longer than the length of the (lower end of the) indenter 22, i.e., longer than the length of the pair of support bases 11 (the pair of support portions 12 and the contact member 13) in the Y-axis direction. In addition, the (lower surface 23 of) the base 21 has a predetermined width 24 in the X-axis direction. The predetermined width 24 of the (lower surface 23 of) the base 21 is larger than the width 25 of the indenter 22. Specifically, the lower surface 23 of the base 21 has a rectangular shape in a plan view that has the predetermined width 24 in the X-axis direction and extends in the Y-axis direction, with a region corresponding to the indenter 22 missing, resulting in two surfaces separated in the X-axis direction.

[0025] The moving unit 30 is provided above the support unit 10 and moves the indenter 22 of the indenter unit 20 relatively close to the test piece 100 supported by the support unit 10, thereby pressing the test piece 100 supported by the support unit 10 with the indenter 22 of the indenter unit 20 to break it. As shown in Figures 3 and 5, the moving unit 30 includes a support plate 31, a ball screw 32, a motor 33, guide rails 34, a moving base 35, an upper support member 36, and a lower support member 37. The support plate 31 is disposed to extend vertically. The ball screw 32 is supported by the support plate 31 so as to be rotatable about an axis along the Z-axis direction. The motor 33 rotates the ball screw 32 about its axis. The guide rails 34 support the moving base 35 so as to be movably in the Z-axis direction.

[0026] The longitudinal directions of the support plate 31, ball screw 32, and guide rail 34 are parallel to the Z-axis direction. The ball screw 32 is threaded into a threaded hole provided in a movable base 35. The guide rail 34 is attached to the support plate 31. The moving unit 30 moves the indenter unit 20 in the Z-axis direction via the movable base 35 by the motor 33 rotating the ball screw 32 around its axis.

[0027] 3 and 5, the movable base 35 is formed in a rectangular parallelepiped shape, and a cylindrical upper support member 36 extending downward is connected to the lower surface side, with a load cell 40 fixed to the lower end side of the upper support member 36. The load cell 40 measures the load with which the indenter 22 of the indenter unit 20 presses against the test piece 100 supported on the pair of support bases 11 of the support unit 10, and outputs the measurement result to the control unit 50. The base 21 of the indenter unit 20 is attached to the underside of the load cell 40 via a cylindrical lower support member 37. In this way, the movable unit 30 supports the load cell 40 via the upper support member 36 and the lower support member 37.

[0028] Before placing the test piece 100 on the pair of support bases 11, the pressing test apparatus 1 uses the support base moving mechanism 14 to adjust the positions of the pair of support bases 11 in the X-axis direction while the moving base 35 and the indenter unit 20 are positioned above by the moving unit 30, and the spacing between the pair of support portions 12 is adjusted to a predetermined spacing 15 according to the dimensions of the test piece 100, etc. The test piece 100 is placed on the pair of support bases 11 so that one of the sides forming the rectangular shape is parallel to the Y-axis direction. The test piece 100 is also placed on the pair of support bases 11 so that it straddles both of the pair of support portions 12 in the X-axis direction. When the test piece 100 is placed on the pair of support bases 11 in this manner, both end portions are supported by the support bases 11, and the center portion overlaps between the pair of support bases 11.

[0029] A pair of plate-shaped connecting members is provided on both side surfaces in the X-axis direction of the moving base 35 of the moving unit 30, and a rectangular parallelepiped transparent container 39 that covers the lower end of the indenter 22 is detachably (removably) provided via the pair of connecting members. The transparent container 39 is transparent to light rays such as visible light captured by the imaging unit 91 (described later), and is formed in a box shape from a material that is transparent to visible light, such as glass or plastic. An indenter insertion hole is formed in the transparent container 39, and the indenter 22 is inserted into the indenter insertion hole and positioned above the lower end of the indenter 22. The transparent container 39 is moved in the Z-axis direction together with the base 21 and the indenter 22 via the moving base 35 by the moving unit 30. The transparent container 39 moves downward along the Z-axis direction together with the base 21 and the indenter 22, and when the lower end of the indenter 22 approaches the surface 101 of the test piece 100 supported on a pair of support stands 11 of the support unit 10, it is positioned in a position covering the upper part of the pair of support stands 11 of the support unit 10.

[0030] As shown in FIG. 3 , the compression testing apparatus 1 further includes an imaging unit 91. The imaging unit 91 is positioned so as to capture an image of the test piece 100 supported on the pair of support bases 11 of the support unit 10 from the side. The imaging unit 91 is positioned outside the transparent container 39 and captures an image of light passing through the transparent container 39 from inside the transparent container 39 through the transparent container 39. For example, the imaging unit 91 is a visible light camera that captures visible light passing through the transparent container 39, but the present invention is not limited to this. In the example of embodiment 1 shown in FIG. 3 , the imaging unit 91 is positioned outside the transparent container 39 and laterally with respect to the pair of support bases 11 of the support unit 10 and captures an image of the pair of support bases 11 of the support unit 10 and the test piece 100 supported on the pair of support bases 11 from the side through the transparent container 39.

[0031] The imaging unit 91 includes an imaging element that images the pair of support bases 11 of the support unit 10 and the test piece 100 supported on the pair of support bases 11. The imaging element is, for example, a CCD (Charge-Coupled Device) imaging element or a CMOS (Complementary MOS) imaging element. The imaging unit 91 images the pair of support bases 11 of the support unit 10 and the test piece 100 supported on the pair of support bases 11 from the side, and outputs the captured image to the control unit 50.

[0032] When the indenter 22 presses the test piece 100, the imaging unit 91 captures images from the side of the pair of support stands 11 of the support unit 10 and the test piece 100 supported on the pair of support stands 11, as well as the lower end of the indenter 22 pressing against the test piece 100, thereby allowing observation of the state of the test piece 100 being pressed and destroyed by the lower end of the indenter 22, the state of the test piece 100 being pressed against the lower end of the indenter 22, the condition of the lower end of the indenter 22 (whether or not there is any foreign matter attached, whether or not there is any chipping, etc.), etc.

[0033] 3, the pressurization test apparatus 1 is further provided with a notification unit 92. The notification unit 92 notifies the operator of various processing results, detection results, measurement results, judgment results, evaluation results, etc., performed by the pressurization test apparatus 1 in a manner that the operator can recognize, in response to commands output from the control unit 50. In the first embodiment, the notification unit 92 is, for example, a display unit, a light-emitting unit, or an audio unit.

[0034] The display unit serving as the notification unit 92 is provided on a cover (not shown) of the compression test apparatus 1 with its display surface facing outward. The display unit displays a screen for setting various conditions related to various processes of the compression test apparatus 1, such as testing and evaluation by the compression test apparatus 1 and imaging by the imaging unit 91, as well as acquired images and data, various processing results, detection results, measurement results, calculation results, and judgment results by the control unit 50, and evaluation results by the control unit 50 (described later), so that the operator can see them. The display unit is configured with a liquid crystal display device or the like. The display unit is provided with an input unit that the operator uses to input information related to the various conditions of the compression test apparatus 1 and information related to the display of images, etc. The input unit provided on the display unit is configured with at least one of a touch panel provided on the display unit and a keyboard, etc. The display unit is not fixed to the compression test apparatus 1 but may be provided on any communication device, and the communication device may be connected to the compression test apparatus 1 wirelessly or via a wire.

[0035] The light-emitting unit serving as the notification unit 92 is provided above a cover (not shown) of the compression test apparatus 1. The light-emitting unit is composed of, for example, a light-emitting diode, and by lighting up, blinking, changing the color of light, etc., the light-emitting diode notifies the operator of errors, judgment results, evaluation results, etc. that have occurred during various processes by the compression test apparatus 1 in a recognizable manner. The audio unit serving as the notification unit 92 is composed of, for example, a speaker, and by emitting audio from the speaker, etc., notifies the operator of errors, judgment results, evaluation results, etc. that have occurred during various processes by the compression test apparatus 1 in a recognizable manner.

[0036] 3, the indentation test apparatus 1 is further provided with a gas supply unit 93. The gas supply unit 93 injects gas supplied from a gas supply source toward the lower end of the indenter 22, which is covered by the transparent container 39, and the area around the lower end of the indenter 22. By injecting gas in this manner, the gas supply unit 93 can remove foreign matter adhering to the lower end of the indenter 22 and the area around the lower end of the indenter 22, thereby maintaining the lower end of the indenter 22 in good condition.

[0037] As shown in Fig. 3, the compression testing apparatus 1 is further provided with a fragment discharge unit 94. The fragment discharge unit 94 introduces negative pressure supplied from a suction source into the space covered by the transparent container 39, thereby collecting and removing fragments of the test piece 100 that are generated during the destructive testing of the test piece 100. By introducing such negative pressure, the fragment discharge unit 94 can suitably collect and remove fragments of the test piece 100 that are generated during the destructive testing of the test piece 100, thereby maintaining a good condition within the space covered by the transparent container 39 where the destructive testing of the test piece 100 is performed.

[0038] In the first embodiment, the control unit 50 controls the operation of each component of the compression test apparatus 1, causing the compression test apparatus 1 to perform various operational processes, including the evaluation method for a compression test apparatus according to the first embodiment. The control unit 50 acquires, from the load cell 40, measurement results obtained by measuring the load (force in the Z-axis direction) applied to the indenter 22 by pressing the test piece 100, from immediately before the indenter 22 starts pressing the test piece 100 to immediately before the test piece 100 breaks, and acquires, based on the measurement results acquired from the load cell 40, a load at break, which is a measurement value of the load cell 40 at the time (instant) when the test piece 100 breaks. Based on the acquired load at break, the control unit 50 calculates the strength (transverse strength, bending strength) of the broken test piece 100, and stores the calculated strength of the test piece 100 or notifies it via the notification unit 92.

[0039] In the first embodiment, the control unit 50 includes a computer system. The computer system included in the control unit 50 includes an arithmetic processing device having a microprocessor such as a CPU (Central Processing Unit), a storage device having memory such as a ROM (Read Only Memory) or RAM (Random Access Memory), and an input / output interface device. The arithmetic processing device of the control unit 50 performs arithmetic processing in accordance with a computer program stored in the storage device of the control unit 50, and outputs control signals for controlling the pressing test apparatus 1 to each component of the pressing test apparatus 1 via the input / output interface device of the control unit 50.

[0040] Next, this specification will explain, with reference to the drawings, an evaluation method for the compression test apparatus according to embodiment 1, which is an example of the operation process performed by the compression test apparatus 1 according to embodiment 1. Fig. 7 is a cross-sectional view illustrating the measurement step 1003 in Fig. 1. Fig. 8 is a graph illustrating the evaluation step 1004 in Fig. 1.

[0041] The preparation step 1001 is a step of preparing a pressing test apparatus 1 that includes a support unit 10 having a pair of support parts 12 that extend parallel to each other with a gap 15 between them and support the back surface 102, which is the underside of the test piece 100; an indenter unit 20 that is arranged above the support unit 10 and between the pair of support parts 12 and is composed of a base 21 and an indenter 22 that stands upright from approximately the center of the base 21 and presses the test piece 100 supported by the support unit 10; a moving unit 30 that moves the indenter unit 20 closer to the test piece 100 supported by the support unit 10; and a load cell 40 that measures the load with which the indenter 22 of the indenter unit 20 presses the test piece 100 supported by the support unit 10.

[0042] In the preparation step 1001, in the first embodiment, the moving unit 30 positions the moving base 35 and the indenter unit 20 in an upward position in the compression testing apparatus 1, and in this state, the support base moving mechanism 14 adjusts the positions of the pair of support bases 11 in the X-axis direction to adjust the predetermined distance 15 to be larger than the width 25 of the indenter 22 and smaller than the width 24 of the lower surface 23 of the base 21, thereby positioning the pair of support bases 11 in a position where the lower surface 23 of the base 21 and the pair of supports 12 face each other in the vertical direction (Z-axis direction), as shown in Fig. 6. Also, in the preparation step 1001, the transparent container 39 is removed from the compression testing apparatus 1 so that there is no transparent container 39 between the lower surface 23 of the base 21 and the pair of supports 12 of the pair of support bases 11, and the lower surface 23 of the base 21 can directly contact the pair of supports 12 of the pair of support bases 11 in the movement step 1002 described below.

[0043] The moving step 1002 is a step that occurs after the preparation step 1001, in which the moving unit 30 moves the indenter unit 20 toward the support unit 10 at a constant speed while the support unit 10 is not supporting the test piece 100, as shown in Fig. 7. In the first embodiment, the moving step 1002 is continued until the lower surface 23 of the base 21 of the indenter unit 20 comes into contact with the support unit 10, and continues until the lower surface 23 of the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of supports 12 of the support unit 10, as shown in Fig. 7.

[0044] The measuring step 1003 is a step in which the base 21 of the indenter unit 20 comes into contact with the support unit 10 and the load applied by the indenter unit 20 is measured by the load cell 40. In the first embodiment, the measuring step 1003 is a step in which the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of support parts 12 of the support unit 10 and the load applied by the indenter unit 20 is measured by the load cell 40. In measurement step 1003, from the state in which the underside 23 of the base 21 of the indenter unit 20 is in contact with the upper surfaces of the pair of support portions 12 of the support unit 10, the moving unit 30 continues to operate to move the indenter unit 20 closer to the support unit 10 at a constant speed, so that the underside 23 of the base 21 of the indenter unit 20 presses against the upper surfaces of the pair of support portions 12 of the support unit 10, and the load (force in the Z-axis direction) applied to the indenter unit 20 (base 21) due to this pressure is measured by the load cell 40, and the measurement results are output to the control unit 50 as appropriate.

[0045] In the measuring step 1003, in accordance with the time elapsed from the moment the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of supports 12 of the support unit 10, i.e., the time during which the moving unit 30 continues to operate to move the indenter unit 20 closer to the support unit 10 at a uniform speed from the moment the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of supports 12 of the support unit 10, the moving unit 30 continues to operate to move the indenter unit 20 closer to the support unit 10 at a uniform speed, and a load is applied and accumulated from the lower surface 23 of the base 21 of the indenter unit 20 to the upper surfaces of the pair of supports 12 of the support unit 10. In other words, in the measuring step 1003, the time elapsed from the moment the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of supports 12 of the support unit 10 is a physical quantity equivalent to the accumulated amount of load applied from the lower surface 23 of the base 21 of the indenter unit 20 to the upper surfaces of the pair of supports 12 of the support unit 10. Therefore, in the measurement step 1003, the control unit 50 measures the load using the load cell 40 while measuring the elapsed time from the moment the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of supports 12 of the support unit 10, and by linking this elapsed time with the load measurement results obtained by the load cell 40, it is possible to obtain correlation data 61, as shown in Figure 8, which essentially represents the correlation between the cumulative amount of load (the horizontal axis of the graph in Figure 8) and the load measured by the load cell 40 (the vertical axis of the graph in Figure 8).

[0046] When the pressing test apparatus 1 is in a completely normal state, the reference correlation data 71 (see FIG. 8 ) representing the correlation between the load and the load obtained in the measurement step 1003 indicates that the load and the load are proportional to each other and are plotted as a straight line on a graph with the load on the horizontal axis and the load on the vertical axis. Therefore, obtaining such correlation data and evaluating the state of the pressing test apparatus 1 is referred to as evaluating the linearity of the load cell 40. When the pressing test apparatus 1 is in a normal state, the correlation data representing the correlation between the load and the load obtained in the measurement step 1003 falls within a linear correlation threshold line 72 (see FIG. 8 ) that is centered on the reference correlation data 71 and shifted by a predetermined linearity error threshold in the positive or negative direction of the load or the load. On the other hand, when the pressing test apparatus 1 is out of the normal state, i.e., in an abnormal state, the correlation data representing the correlation between the load and the load obtained in the measurement step 1003 falls outside the range between the correlation threshold lines 72. The reference correlation data 71 is acquired in advance in the same manner as in measurement step 1003 and stored in the control unit 50, and the correlation threshold line 72 is calculated in advance based on the previously acquired reference correlation data 71 and stored in the control unit 50.

[0047] The evaluation step 1004 is a step of evaluating the state of the pressing test apparatus 1 based on the load acquired in the measurement step 1003. Specifically, in the evaluation step 1004, if the correlation data 61 acquired in the measurement step 1003 falls within the pre-stored correlation threshold lines 72 as shown in FIG. 8 , the control unit 50 determines that the pressing test apparatus 1 is in a state that is within a normal range with respect to the linearity of the load cell 40. Also, in the evaluation step 1004, if at least a portion of the correlation data 61 acquired in the measurement step 1003 falls outside the pre-stored correlation threshold lines 72, the control unit 50 determines that the pressing test apparatus 1 is in a state that is outside the normal range with respect to the linearity of the load cell 40, i.e., that the pressing test apparatus 1 is in an abnormal state. In the evaluation step 1004, the control unit 50 may notify the operator of this determination result via the notification unit 92 in a recognizable manner.

[0048] In the evaluation method for the press test apparatus according to the first embodiment having the above-described configuration, the indenter unit 20 is moved toward the support unit 10 at a constant speed by the moving unit 30 while the support unit 10 is not supporting the test piece 100, and the base 21 of the indenter unit 20 comes into contact with the support unit 10, the load applied by the indenter unit 20 is measured by the load cell 40, and the state of the press test apparatus 1 (the state of the linearity of the load cell 40) is evaluated based on this acquired load. Therefore, the evaluation method for the press test apparatus according to the first embodiment has the advantageous effect of being able to evaluate the linearity of the load cell 40 while avoiding the hassle of the operator placing a test plate and preventing the indenter 22 from pressing against a hard test plate.

[0049] Furthermore, in the evaluation method of the pressing test apparatus of embodiment 1, in the measurement step 1003, the base 21 of the indenter unit 20 contacts the upper surfaces of the pair of support portions 12 of the support unit 10, and the load applied by the indenter unit 20 is measured by the load cell 40. Therefore, by pressing the upper surfaces of the pair of support portions 12 of the hard support unit 10 with the base 21 of the hard indenter unit 20, more specifically, it is possible to avoid the hassle of the operator placing a plate-like object for testing, and to avoid the indenter 22 from pressing the hard plate-like object for testing, while also enabling evaluation of the linearity of the load cell 40.

[0050] [Embodiment 2] An evaluation method for a compression test device according to a second embodiment of the present invention will be described with reference to the drawings. Figure 9 is a cross-sectional view illustrating measurement step 1003 of the evaluation method for a compression test device according to the second embodiment. In Figure 9, the same parts as those in the first embodiment are designated by the same reference numerals, and their description will be omitted.

[0051] A compression test apparatus 1-2 for carrying out the evaluation method for a compression test apparatus according to embodiment 2 is the compression test apparatus 1 for carrying out the evaluation method for a compression test apparatus according to embodiment 1, except that the base 21 of the indenter unit 20 is changed to a base 21-2, and the other configurations are the same as those of embodiment 1. As shown in FIG. 9, the base 21-2 of embodiment 2 is the base 21 of embodiment 1, with a recess 27 formed on the lower surface 23.

[0052] The recesses 27 are formed at two positions symmetrical to the position of the lower end of the indenter 22 in the X-axis direction. Like the base 21-2, the indenter 22, and the pair of supports 12, the recesses 27 are formed to extend in the Y-axis direction. The length of the recesses 27 in the Y-axis direction is equal to the length of the base 21 (the lower surface 23), i.e., longer than the length of the indenter 22 (the lower end) and longer than the length of the pair of supports 11 (the pair of supports 12 and the contact member 13). Each recess 27 is formed to have a size and shape that allows each of the pair of supports 12 to be fully inserted therein.

[0053] The evaluation method for the compression test apparatus of embodiment 2 is a modification of the evaluation method for the compression test apparatus of embodiment 1, in that the compression test apparatus used is changed from compression test apparatus 1 to compression test apparatus 1-2.

[0054] In preparation step 1001 of embodiment 2, instead of adjusting the positions of the pair of support bases 11 in the X-axis direction using the support base moving mechanism 14 to adjust the predetermined interval 15 to be larger than the width 25 of the indenter 22 and smaller than the width 24 of the underside 23 of the base 21, and positioning the pair of support bases 11 at a position where the underside 23 of the base 21 and the pair of support portions 12 face each other (opposite each other) along the vertical direction (Z-axis direction), as shown in Figure 9, the position of the pair of support bases 11 in the X-axis direction using the support base moving mechanism 14 is adjusted to match the predetermined interval 15 with the distance between the two recesses 27 in the X-axis direction, and the pair of support bases 11 are positioned at a position where the two recesses 27 and the pair of support portions 12 face each other (opposite each other) along the vertical direction (Z-axis direction).

[0055] In the movement step 1002 of the second embodiment, instead of continuing until the lower surface 23 of the base 21 of the indenter unit 20 contacts the upper surfaces of the pair of support portions 12 of the support unit 10 in the movement step 1002 of the first embodiment, the movement step 1002 is modified so that the movement step 1002 continues until the portion of the lower surface 23 of the base 21 of the indenter unit 20 outside the recess 27 in the X-axis direction contacts the upper surfaces of the contact members 13 of the support unit 10, as shown in FIG. 9.

[0056] In measurement step 1003 of embodiment 2, instead of measuring the load applied by the indenter unit 20 when the lower surface 23 of the base 21 of the indenter unit 20 comes into contact with the upper surfaces of the pair of support portions 12 of the support unit 10 using the load cell 40, as shown in FIG. 9 , the portion of the lower surface 23 of the base 21 of the indenter unit 20 outside the recess 27 in the X-axis direction comes into contact with the upper surfaces of the contact members 13 of the support unit 10, and the load applied by the indenter unit 20 is measured using the load cell 40.

[0057] That is, in the measurement step 1003 of the second embodiment, the control unit 50 measures the elapsed time from the moment when the portion of the indenter unit 20 on the outer side in the X-axis direction from the recess 27 of the lower surface 23 of the base 21 comes into contact with the upper surface of the contact member 13 of the support unit 10, and further moves the indenter unit 20 toward the support unit 10 at a uniform speed by the moving unit 30 from the state where the portion of the indenter unit 20 on the outer side in the X-axis direction from the recess 27 of the lower surface 23 of the base 21 comes into contact with the upper surface of the contact member 13 of the support unit 10. The indenter unit 20 continues to move, pressing the upper surface of the contact member 13 of the support unit 10 with the part of the indenter unit 20 that is outer in the X-axis direction than the recess 27 on the underside 23 of the base 21 in the indenter unit 20, and the load (force in the Z-axis direction) applied to the indenter unit 20 (base 21) by this pressing is measured by the load cell 40.By linking this elapsed time with the load measurement results obtained by the load cell 40, correlation data can be obtained that essentially represents the correlation between the cumulative amount of load and the load measured by the load cell 40.

[0058] Note that in the second embodiment, instead of pressing the upper surfaces of the pair of support portions 12 of the hard support unit 10 with the base 21 of the hard indenter unit 20 as in the first embodiment, the base 21 of the hard indenter unit 20 presses the upper surface of the contact member 13 made of a material softer than the pair of support portions 12. Therefore, the correlation data obtained differs from the correlation data 61 obtained in the first embodiment by the amount of deformation of the contact member 13 due to this pressing. For this reason, in the second embodiment, data different from the reference correlation data 71 and correlation threshold line 72 of the first embodiment are prepared in advance and stored in the control unit 50.

[0059] The evaluation step 1004 of the second embodiment is the same as the evaluation step 1004 of the first embodiment except that the correlation data to be evaluated and the reference correlation data and correlation threshold line that serve as the evaluation criteria are changed.

[0060] The evaluation method for the compression test apparatus of embodiment 2 having the above-mentioned configuration is the same as the evaluation method for the compression test apparatus of embodiment 1, except that instead of pressing the upper surfaces of the pair of support portions 12 of the hard support unit 10 with the base 21 of the hard indenter unit 20, the base 21 of the hard indenter unit 20 presses the upper surface of the contact member 13 made of a material softer than the pair of support portions 12.When the test piece 100 is not supported by the support unit 10, the indenter unit 20 is moved toward the support unit 10 at a constant speed by the moving unit 30, so that the base 21 of the indenter unit 20 comes into contact with the support unit 10, the load applied by the indenter unit 20 is measured by the load cell 40, and the state of the compression test apparatus 1 (the state of linearity of the load cell 40) is evaluated based on this acquired load, as in embodiment 1. Therefore, the evaluation method for the pressing test device of embodiment 2, like the evaluation method for the pressing test device of embodiment 1, has the effect of being able to evaluate the linearity of the load cell 40 while avoiding the hassle of the operator having to place the test plate and preventing the indenter 22 from pressing against a hard test plate.

[0061] Furthermore, in the evaluation method of the pressing test apparatus of embodiment 2, in measurement step 1003, the base 21 of the indenter unit 20 contacts the upper surface of the contact member 13 of the support unit 10, and the load applied by the indenter unit 20 is measured by the load cell 40. Therefore, by pressing the upper surface of the contact member 13, which is made of a material softer than the pair of support parts 12, with the base 21 of the hard indenter unit 20, more specifically, in a manner different from the evaluation method of the pressing test apparatus of embodiment 1, it is possible to avoid the hassle of the operator placing a test plate-like object and to avoid the indenter 22 pressing the hard test plate-like object, while also enabling evaluation of the linearity of the load cell 40.

[0062] The present invention is not limited to the above-described embodiment, and can be implemented in various modifications without departing from the gist of the present invention. [Explanation of symbols]

[0063] 1,1-2 Pressurization test equipment 10 Support Unit 12 Support part 15 intervals 20 Indenter unit 21,21-2 Foundation 22 indenter 30 Mobile Units 40 load cells 100 test specimens 102 Back side 1001 Preparation Steps 1002 movement steps 1003 Measurement Step 1004 Evaluation Step

Claims

1. a preparation step of preparing a pressing test apparatus including: a support unit having a pair of support parts extending parallel to each other with a gap therebetween and supporting the underside of a test piece; an indenter unit arranged above the support unit and between the pair of support parts, the indenter unit being composed of a base and an indenter erected from approximately the center of the base and pressing the test piece supported by the support unit; a movement unit that moves the indenter unit relatively closer to the test piece supported by the support unit; and a load cell that measures the load applied by the indenter of the indenter unit to press the test piece supported by the support unit; a moving step of moving the indenter unit toward the support unit at a constant speed by the moving unit while the support unit is not supporting the test piece; a measuring step of measuring, with the load cell, a load applied by the indenter unit when the base of the indenter unit comes into contact with the support unit; an evaluation step of evaluating the state of the pressing test device based on the load acquired in the measurement step; A method for evaluating a pressing test device comprising:

2. 2. The method for evaluating a pressing test apparatus according to claim 1, wherein the measuring step includes measuring the load applied by the pressing unit when the base of the pressing unit contacts the upper surfaces of the pair of support portions of the support unit using the load cell.

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