Material tester

Abstract

To enable easy acquisition and storage of images showing the presence or absence of fractures and the state of the fractures in a test target object during a material test as an evidence that a fracture analysis has been conducted.SOLUTION: A material tester for performing a material test involving applying a test force to a test target to deform the test target is provided, the material tester comprising an image acquisition unit for acquiring a static image of the test target at predetermined time during a material test, and a recording unit for storing the acquired static image in association with a material test result of the test target in a storage device.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a material testing machine. [Background technology]

[0002] In order to analyze the state of fracture of a test object during a tensile test, a material testing machine that captures a moving image at the time of fracture is known. For example, Patent Document 1 describes a method in which a video camera that captures the test object is moved in accordance with the movement of a chuck that holds the upper end of the test object, and a moving image of the fracture position at the moment of fracture of the test object is captured with high accuracy. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-184170 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been an increasing need to prevent falsification of experimental and analytical data and to provide evidence. Therefore, one of the objectives of the present invention is to leave an image showing the state of the test object as evidence of fracture analysis.

[0005] It is possible to leave the video as evidence, but when a user wants to refer to an image of the moment of fracture, they need to search through the video to find the image they want, which takes time. In material testing, more than 100 samples are often tested in a day, and it takes a huge amount of time to search for and confirm the image of the moment of fracture from the video for each sample.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a materials testing machine that can easily obtain and store images showing the presence or absence of a fracture in a test object during a materials test and the state of the fracture as evidence that a fracture analysis has been performed. [Means for solving the problem]

[0007] One aspect of the present invention relates to a materials testing machine that performs a materials test in which a test force is applied to a test object to deform the test object, and that includes an image acquisition unit that acquires a still image of the test object at a predetermined timing in the materials test, and a recording unit that associates the acquired still image with a test result of the test object in the materials test and stores them in a memory device. Effect of the Invention

[0008] According to the present invention, a materials testing machine can be provided that can easily obtain and store images showing the presence or absence of a fracture in a test object in a materials test and the state of the fracture as evidence that the fracture analysis was performed appropriately. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a tensile testing machine according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram illustrating an example of a configuration of a control device. [Diagram 3] FIG. 13 is a diagram showing an example of an input screen for rupture information. [Figure 4] 10 is a flowchart illustrating an example of a process of a control unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] [1. Configuration of tensile testing machine] FIG. 1 is a diagram showing an example of the configuration of a tensile tester 1 according to the present embodiment. The tensile tester 1 of the present embodiment performs a tensile test by applying a test force to a test object TP that is the subject of the tensile test, to measure mechanical properties such as the tensile strength, yield point, elongation, and reduction of area of ​​the test object TP. The test force is a tensile force. The tensile tester 1 includes a tester body 2 that applies a test force to a test object TP to perform a tensile test, a camera 3 that captures images of the test object TP, and a control unit 4. The control unit 4 controls the tensile test operation by the tester body 2. The control unit 4 also captures images of the test object TP during the tensile test using the camera 3, associates the captured images with the tensile test data, and stores them as evidence for fracture analysis. The tensile tester 1 corresponds to an example of a "material testing machine." The tensile test corresponds to an example of a "material test."

[0012] As shown in FIG. 1, the testing machine body 2 is configured by forming a load frame on a base 10 with a pair of support columns 11, 12 and a yoke 13, and by fixing a crosshead 14 to the support columns 11, 12.

[0013] A hydraulic actuator 15 is disposed on the base 10, and a lower grip 16 for gripping the lower end of the test object TP is attached to a piston rod 15A of the hydraulic actuator 15. In addition, an upper grip 18 for gripping the upper end of the test object TP is attached to the crosshead 14 via a load cell 17.

[0014] In the hydraulic actuator 15, the direction and amount of pressure oil are controlled by a servo valve 19, and the piston rod 15A extends and retracts. As a result, the distance between the upper grip 18 and the lower grip 16 extends and retracts, and a test force is applied to the test object TP fixed between the upper grip 18 and the lower grip 16. In addition, the stroke of the hydraulic actuator 15, i.e., the displacement of the test object TP, is detected by a differential transformer 20 attached to the hydraulic actuator 15.

[0015] The load cell 17 is a sensor that measures a test force, which is a tensile load applied to the test object TP, and outputs a test force measurement signal SG1 to the control unit 4. The differential transformer 20 is a sensor that measures the amount of displacement of the test object TP and outputs to the control unit 4 a displacement measurement signal SG2 corresponding to the amount of displacement.

[0016] A displacement sensor 21 is disposed on the test object TP. The test object TP is, for example, a dumbbell-shaped object formed with a constricted center. The displacement sensor 21 is a sensor that measures an elongation measurement value ED by measuring the distance between a pair of reference points on the test object TP, and outputs an elongation measurement signal SG3 to the control unit 4. The pair of reference points are disposed at the top and bottom of the constricted region of the test object TP.

[0017] The testing machine main body 2 further includes an electric power source GE and a hydraulic power source GP. The power source GE supplies power to each part of the testing machine main body 2. The power source GE supplies power to, for example, various motors to drive them. The power source GE also supplies power to a hydraulic pump and a hydraulic control valve (not shown) to drive them. The power source GE is configured as, for example, a voltage source. The power source GE supplies a corresponding voltage to each part of the testing machine main body 2. For example, the power source GE supplies a voltage of 100 V to the hydraulic pump and various motors, and supplies a voltage of 10 V to the control unit 4.

[0018] The hydraulic power source GP supplies hydraulic pressure to a hydraulic device constituting the testing machine main body 2. The hydraulic power source GP supplies hydraulic pressure to, for example, a hydraulic actuator 15 to drive the hydraulic actuator 15. That is, the hydraulic actuator 15 is driven by the hydraulic pressure supplied from the hydraulic power source GP, and the piston rod 15A is extended and contracted. The hydraulic power source GP includes a hydraulic pump and a hydraulic control valve (not shown), and generates hydraulic pressure by driving the hydraulic pump. The hydraulic pump is supplied with power from a power source GE. The hydraulic control valve adjusts the hydraulic pressure output from the hydraulic power source GP.

[0019] The camera 3 is disposed at a position where the test object TP fixed between the upper grip 18 and the lower grip 16 can be captured in the imaging field of view. The camera 3 is, for example, a digital camera using a CCD image sensor, a CMOS image sensor, or the like, and having a pixel count of several million or more. The camera 3 captures an image of the test object TP in response to an instruction from the control unit 4, and outputs the image data to the control unit 4. The imaging range of the test object TP by the camera 3 includes, for example, at least the range between a pair of reference points measured by the displacement sensor 21. The camera 3 is supported, for example, by a stand 22 disposed near the base 10.

[0020] The control unit 4 includes a signal input / output device 30 and a control device 40 . The signal input / output device 30 constitutes an input / output interface circuit that transmits and receives signals to and from the testing machine main body 2. The signal input / output device 30 of this embodiment has a first sensor amplifier 31, a second sensor amplifier 32, a third sensor amplifier 33, and a servo amplifier 34.

[0021] The first sensor amplifier 31 is a device that amplifies the test force measurement signal SG1 output by the load cell 17 to generate a test force measurement value FD, and outputs the test force measurement value FD to the control device 40. The test force measurement value FD indicates the test force applied to the test object TP. The second sensor amplifier 32 is a device that amplifies the extension measurement signal SG3 output by the displacement sensor 21 to generate an extension measurement value ED, and outputs the extension measurement value ED to the control device 40. The extension measurement value ED indicates the extension of the test object TP. The third sensor amplifier 33 is a device that amplifies the displacement measurement signal SG2 output by the differential transformer 20 to generate a displacement measurement value XD, and outputs the generated displacement measurement value XD to the control device 40. The displacement measurement value XD indicates the displacement X of the hydraulic actuator 15. The servo amplifier 34 is a device that controls the servo valve 19 in accordance with the control of the control device 40. The control device 40 generates a command value CD based on at least one of the test force measurement value FD and the displacement measurement value XD, and outputs the generated command value CD to the servo amplifier 34. The servo amplifier 34 generates a command signal SG4 indicative of the command value CD, and outputs the generated command signal SG4 to the servo valve 19. The servo valve 19 controls the pressure oil direction and pressure oil amount for the hydraulic actuator 15 in accordance with the command signal SG4 output from the servo amplifier 34.

[0022] [2. Control device configuration] The control device 40 controls the operation of the testing machine main body 2 based on an operation by a user, and causes the testing machine main body 2 to execute a tensile test. The control device 40 also acquires an image of the test object TP from the camera 3 during the tensile test.

[0023] FIG. 2 is a diagram showing an example of the configuration of the control device 40. As shown in FIG. The control device 40 includes an operation panel 41, a control unit 42, and a storage device 43 configured with a hard disk drive (HDD) or a solid state drive (SSD) or the like.

[0024] The operation panel 41 includes a touch panel 411 and an input device 412 other than the touch panel 411, such as buttons and a numeric keypad. The touch panel 411 includes an LCD (Liquid Crystal Display) or the like, and displays various images on the LCD according to instructions from the control unit 42. The touch panel 411 also includes a touch sensor arranged along the display surface of the LCD. The touch sensor detects a touch with a user's fingertip or pen, and transmits a detection signal to the control unit 42. The touch panel 411 corresponds to the display device in this disclosure.

[0025] In the storage device 43, a test result file 431 and an image file 432 are stored by the control unit .

[0026] Test results, which are tensile property data of the test object TP obtained by the tensile test, are stored in the test result file 431. The tensile property data includes data on the test force measurement value FD, the elongation measurement value ED, and the displacement measurement value XD measured during the tensile test for each test object TP. The image file 432 stores image data of a still image of the test object TP during the tensile test, captured by the camera 3.

[0027] The control unit 42 controls the operation of the control device 40. The control unit 42 includes a processor 44 and a memory 45. The processor 44 is a computer equipped with a CPU (Central Processing Unit), an MPU (Micro-Processing Unit), and the like. The memory 45 is composed of a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The memory 45 stores a control program 451.

[0028] The control unit 42 may be, for example, a personal computer, a tablet terminal, or a smartphone.

[0029] [3. Control Unit Configuration] The control unit 42 includes, as functional elements or functional units, a communication unit 441, a test execution unit 442, an image acquisition unit 443, a recording unit 444, and a breakage information acquisition unit 445.

[0030] These functional elements of the control unit 42 are realized, for example, by the processor 44 of the control unit 42, which is a computer, executing a control program 451 stored in the memory 45. The control program 451 can be stored in any computer-readable storage medium. Alternatively, all or part of the above-mentioned functional elements of the processor 44 can be configured by hardware including one or more electronic circuit components. Such electronic circuits can be programmed hardware such as a DSP (Digital Signal Processor) or an FPGA (Field Programmable Gate Array), or a SoC (System-on-a-Chip)-FPGA.

[0031] The communication unit 441 controls communication with the signal input / output device 30 and communication with the camera 3 . The communication unit 441 receives, for example, a test force measurement value FD, an elongation measurement value ED, and a displacement measurement value XD from the signal input / output device 30. In addition, the communication unit 441 transmits, for example, a command value CD to the signal input / output device 30. In addition, the communication unit 441 gives an image capture instruction to the camera 3 and acquires image data from the camera 3.

[0032] The test execution unit 442 controls the hydraulic actuator 15 according to the conventional technology to apply a test force to the test object TP and executes a tensile test. The test execution unit 442 executes the tensile test according to, for example, test conditions input by a user to the operation panel 41. The test conditions may include an end condition of the tensile test, that is, a condition for terminating the operation of the hydraulic actuator 15 and terminating the execution of the tensile test. The end condition may include, for example, an upper limit value of the test force and / or an upper limit elongation amount of the test object TP.

[0033] The test execution unit 442 outputs a command value CD to the servo amplifier 34 to control the operation of the hydraulic actuator 15 so that, for example, the elongation measurement value ED indicating the elongation of the test object TP obtained from the second sensor amplifier 32 increases at a constant speed specified in the test conditions. Alternatively, the test execution unit 442 outputs a command value CD to the servo amplifier 34 to control the operation of the hydraulic actuator 15 so that, for example, when the test object TP starts to plastically deform, the test force measurement value FD indicating the test force applied to the test object TP obtained from the first sensor amplifier 31 becomes a constant value specified in the test conditions. In addition, when the end condition of the tensile test specified in the test conditions is satisfied, the test execution unit 442 ends the operation of the hydraulic actuator 15 to end the execution of the tensile test.

[0034] The image acquisition unit 443 acquires a still image of the test object TP at a predetermined timing in the tensile test using the camera 3. When the test object TP does not break during the tensile test, the predetermined timing is after the execution of the tensile test is completed. Specifically, the execution of the tensile test may be completed when, for example, a termination condition specified by the test conditions input by the user is satisfied, when the hydraulic actuator 15 finishes applying the test force to the test object TP, when a signal indicating the end is issued, or when the upper grip 18 or the lower grip 16 is released from the test object TP.

[0035] The image acquiring unit 443 acquires a still image of the test object TP by the camera 3, for example, when a notification that the end condition has been satisfied is received from the test executing unit 442, or when the test force measurement value FD acquired from the first sensor amplifier 31 falls below a predetermined value. Here, the time when the test force measurement value FD falls below a predetermined value may include, for example, a decrease in the test force caused by the end of the operation of the hydraulic actuator 15, or a decrease in the test force caused by removing the test object TP from the upper grip 18 or the lower grip 16.

[0036] Also, when the test object TP breaks during the execution of the tensile test, the predetermined timing is after the break occurs. The image acquisition unit 443 detects the breakage of the test object TP from, for example, a change over time in the test force measurement value FD acquired from the first sensor amplifier 31. Specifically, the image acquisition unit 443 may determine that the test object TP has broken when the test force measurement value FD decreases by a width equal to or greater than a predetermined threshold value during the execution of a tensile test. When the image acquisition unit 443 determines that the test object TP has broken, it acquires a still image of the test object TP by the camera 3. Note that the method of detecting the breakage is not limited to the above, and publicly known techniques may be applied.

[0037] The above-mentioned predetermined timing is also when an abnormality is detected during the execution of a tensile test. The definition of an abnormality is often designed within the control unit, and an abnormality is detected when the detector result meets the abnormality definition, and a still image is captured by the camera 3. Note that there are also tests in which the test continues even if an abnormality is detected. In such cases, it is difficult to determine the presence or absence of an abnormality from the test result information, but the present invention makes it possible to confirm the presence or absence of an abnormal state as well as visual information of the testing machine at that time.

[0038] The recording unit 444 collects tensile characteristic data of the test object TP in the tensile test executed by the test execution unit 442. The tensile characteristic data may include, for example, time-series data of the test force measurement value FD, the elongation measurement value ED, and the displacement measurement value XD measured during the tensile test. The recording unit 444 stores the test results including the tensile characteristic data and the still images of the test object TP acquired by the image acquisition unit 443 in the storage device 43 in association with each other.

[0039] As a result, a still image of the tensile object TP as evidence indicating whether or not the tensile object TP broke in the tensile test and / or the location of the break is stored in the storage device 43 in association with the test result of the tensile test on the test object TP. Since the still image as evidence is acquired by the image acquisition unit 443 at a predetermined timing in the tensile test as described above, even when tensile tests are performed on more than 100 samples in a day, for example, the user does not need to search for and acquire an image of the moment of breakage from the moving images in each tensile test as in the conventional technology.

[0040] Therefore, with the tensile testing machine 1, still images of the test object TP can be easily acquired and stored as evidence that the fracture analysis of the test object TP in the tensile test was properly performed.

[0041] Here, the recording unit 444 can store, for example, the test results for the test subject TP and the still image of the test subject TP acquired by the image acquisition unit 443 as different files in the storage device 43. In this embodiment, the recording unit 444 stores the test results as a test result file 431 in the storage device 43, and stores the still image of the test subject TP as an image file 432 in the storage device 43. The recording unit 444 then stores access information to the image file 432 (for example, the address of the storage location of the image file 432 in the storage device 43, etc.) in the test result file 431.

[0042] In this way, by storing the test results and the still images as separate files in the storage device 43, it is possible to prevent the still images of the test subject TP as evidence from being counterfeited by being overwritten with other images at a later date. In order to more effectively prevent such counterfeiting, the access information to the image file 432 stored in the test result file 431 may be expressed, for example, as an encrypted code.

[0043] The break information acquisition unit 445 acquires an input of break information, which is information about a break position in the test object TP. The break information is input by a user via, for example, the operation panel 41. When the test object TP breaks during the execution of a tensile test, the break information acquisition unit 445 displays an input screen for the break information on the touch panel 411. Alternatively, the user can instruct the control unit 42 via the operation panel 41 to display an input screen for the break information on the touch panel 411 after, for example, the tensile test is completed.

[0044] When displaying an input screen for inputting rupture information on the touch panel 411, the rupture information acquisition unit 445 displays the input screen on the touch panel 411 together with the still image of the test object TP acquired by the image acquisition unit 443.

[0045] 3 is a diagram showing an example of a breakage information input screen displayed on the touch panel 411 by the breakage information acquisition unit 445. In this breakage information input screen 50, a still image of the test object TP acquired by the image acquisition unit 443 is displayed in a box 51 on the right side of the figure. As an example, the test object TP shown in the figure is broken between two reference points S1 and S2, one above the other, which are marked in a diamond shape on the surface of the test object TP.

[0046] On the left side of the fracture information input screen, buttons B1, B2, and B3 are displayed for selecting one of three fracture position classifications, "Fracture A," "Fracture B," and "Fracture C," to be recorded in the test record as fracture information. Here, the fracture position classifications indicated by "Fracture A," "Fracture B," and "Fracture C" may be in accordance with, for example, Japanese Industrial Standard JIS Z2241 "Method of tensile testing of metallic materials."

[0047] The user can input the breakage position classification as breakage information by referring to the still image of the test object TP in the box 51, determining the classification of the breakage position, touching the button B1, B2, or B3 corresponding to the breakage position classification, and then touching the decision button 52. In the illustrated example, the button B1 is selected, and breakage information indicating that the breakage position classification is "A break" is input. Note that, although the present embodiment describes a case where the user inputs the information, the breakage may also be classified using a judgment program in the testing machine system.

[0048] The break information acquisition unit 445 acquires the input break location classification and sends it to the recording unit 444. The recording unit 444 includes the transmitted break location classification as break information in the test results and stores it in the test result file 431 of the storage device 43. Note that if the user wishes to input the break location classification later, he or she can touch the cancel button 53 to terminate the display of the break information input screen.

[0049] [4. Processing of control unit] Fig. 4 is a flowchart showing an example of the processing of the control unit 42. The processing shown in Fig. 4 starts when the power of each part of the tensile tester 1 is turned on, and is executed repeatedly. When the process starts, the test execution unit 442 determines (S100) whether or not test conditions have been input from the operation panel 41. If no test conditions have been input (S100, NO), the test execution unit 442 repeats step S100 and waits for the test conditions to be input.

[0050] On the other hand, when the test conditions have been input (S100, YES), the test execution unit 442 next judges whether or not a test start instruction has been input from the operation panel 41 (S102). If the test start instruction has not been input (S102, NO), the test execution unit 442 repeats step S102 and waits for the test start instruction to be input.

[0051] On the other hand, when a test start command is input (S102, YES), the test execution unit 442 executes a tensile test (S104). Next, the test execution unit 442 and the image acquisition unit 443 determine whether or not the test object TP has broken while the tensile test is being performed (S106). Alternatively, only the test execution unit 442 may determine whether or not the test object TP has broken, and the image acquisition unit 443 may receive the determination result from the test execution unit 442.

[0052] Then, when the test object TP breaks (S106, YES), the image acquisition unit 443 acquires a still image of the broken test object TP by the camera 3 (S108). The test execution unit 442 instructs the hydraulic actuator 15 to stop applying the test force and terminates the execution of the tensile test (S110). In addition, the break information acquisition unit 445 displays a break information input screen as shown in Fig. 3 on the touch panel 411 and acquires an input of the break position classification as break information (S112). The break information acquisition unit 445 passes the acquired break information to the recording unit 444 as a part of the test record.

[0053] The recording unit 444 associates the test results of the tensile test executed by the test execution unit 442 in step S104 with the still image of the test object TP acquired by the image acquisition unit 443 in step S108, and stores them in the storage device 43 (S114). As described above, the test results and the still image are respectively stored in separate files, for example, the test result file 431 and the image file 432. Then, the recording unit 444 ends this process.

[0054] On the other hand, if the test object TP does not break in step S106 (S106, NO), the test execution unit 442 determines whether or not the termination condition of the tensile test is satisfied (S116). The termination condition may be input as part of the test conditions in the above-mentioned step S100. Then, if the termination condition is not satisfied (S116, NO), the test execution unit 442 returns to step S104 and continues the execution of the tensile test.

[0055] On the other hand, when the termination condition is satisfied (S116, YES), the test execution unit 442 ends the application of the test force to the test object TP and ends the execution of the tensile test (S118). Next, the image acquisition unit 443 acquires a still image of the test object TP (S120), and then moves the process to step S114. In step S114, the recording unit 444 associates the test results of the tensile test executed in step S104 with the still image acquired in step S120 and stores them in the test result file 431 and the image file 432 of the storage device 43, respectively.

[0056] [4. Other embodiments] The tensile testing machine 1 according to the embodiment described above is merely an example of an embodiment of a material testing machine according to the present invention, and any modification and application is possible without departing from the gist of the present invention.

[0057] For example, the control unit 42 may have a function of displaying the test results and still images of the test subject TP on the touch panel 411 by referring to the test result file 431 and the image file 432 stored in the storage device 43. The control unit 42 may display the test results and still images on the touch panel 411, for example, in response to an instruction from the user via the operation panel 41. In this case, the control unit 42 may display the test results in a graph or other format that is easy for the user to refer to.

[0058] In addition, although the storage device 43 is provided in the control device 40 in the above-described embodiment, it may be provided in another device communicatively connected to the control device 40. Such another device may be, for example, a server device communicatively connected to the control device 40 via a communication network. This makes it possible to refer to the test results and still images of the test object TP by any device connected to the communication network.

[0059] In the above embodiment, the material testing machine is the tensile testing machine 1, but the present embodiment is not limited to this. The material testing machine may apply a test force to the test object TP and deform the test object TP to perform a material test. For example, the material testing machine may be a compression testing machine, a bending testing machine, or a torsion testing machine.

[0060] 1 and 2 show functional configurations, and the specific implementation form is not particularly limited. In other words, it is not necessary to implement hardware that corresponds to each functional unit individually, and it is of course possible to implement a configuration in which one processor executes a program to realize the functions of multiple functional units. Also, some of the functions realized by software in the above embodiments may be realized by hardware, or some of the functions realized by hardware may be realized by software.

[0061] In addition, the processing units in the flowchart shown in Fig. 4 are divided according to the main processing contents in order to facilitate understanding of the processing of the control unit 42. There is no limitation to the manner of division or names of the processing units shown in the flowchart of Fig. 4, and the processing units can be further divided according to the processing contents, or one processing unit can be divided to include further processes. In addition, the processing order of the above flowchart is not limited to the example shown in the figure.

[0062] [5. Aspects] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0063] (Section 1) A material testing machine (1) according to one embodiment is a material testing machine that performs a material test in which a test object (TP) is deformed by applying a test force to the test object, and includes an image acquisition unit (443) that acquires a still image of the test object at a predetermined timing in the material test, and a recording unit (444) that associates the acquired still image with a test result of the test object in the material test and stores them in a memory device (43).

[0064] According to the material testing machine described in paragraph 1, still images of the test object at a predetermined timing in the material test are stored in a storage device in association with the test results of the material test. Therefore, the still images can be easily acquired and stored as evidence that the fracture analysis was properly performed in the material test.

[0065] (Section 2) In the material testing machine described in paragraph 1, the predetermined timing is after the occurrence of breakage of the test object in the material test or after the application of the test force is terminated.

[0066] According to the material testing machine described in paragraph 2, still images showing the presence or absence of fracture in the test object during material testing and the state of the fracture can be easily obtained and stored as evidence that the fracture analysis was performed appropriately.

[0067] (Section 3) In the material testing machine described in paragraph 1 or 2, the recording unit stores the test results and the still images for the test object as different files in the storage device, and saves access information to the still image file in the test result file.

[0068] According to the material testing machine described in paragraph 3, it is possible to effectively prevent still images of the test subject, which serve as evidence that the fracture analysis has been performed appropriately, from being tampered with illegally.

[0069] (Section 4) In the material testing machine described in any one of paragraphs 1 to 3, a fracture information acquisition unit (445) is provided that acquires input of fracture information, which is information about the fracture position in the test object, and the fracture information acquisition unit displays an input screen for the fracture information on a display device (411) together with the acquired still image.

[0070] According to the material testing machine described in paragraph 4, a user can perform fracture analysis while referring to a still image of a fractured test object, and can easily input appropriate fracture information.

[0071] (Section 5) A material testing machine that performs a material test in which a test force is applied to a test object to deform the test object, the material testing machine comprising: a fracture information acquisition unit that acquires information on a fracture location classification for the test object; and a recording unit that associates the acquired fracture location classification with a test result of the test object in the material test and stores them in a memory device.

[0072] According to the material testing machine described in paragraph 5, the fracture location classification of the test object in the material test and the test results of the material test are recorded in correspondence with each other, so that the record can be used as evidence that the fracture analysis in the material test was performed appropriately. [Explanation of symbols]

[0073] 1. Tensile testing machine (material testing machine) 2 Testing machine body 3. Camera 4. Control Unit 15 Hydraulic Actuator 17 Load Cell 20 Differential transformer 21 Displacement Sensor 40 Control device 41 Operation Panel 411 Touch Panel 43 Storage device 431 Test Result File 432 Image files 442 Test Execution Department 443 Image Acquisition Unit 444 Recording Department 445 Break Information Acquisition Unit

Claims

1. A material testing machine for performing a material test in which a test object is deformed by applying a test force to the test object, an image acquisition unit that acquires a still image of the test object at a predetermined timing during the material test; a recording unit that stores the acquired still image and the test result of the test subject in the material test in a storage device in association with each other; A material testing machine comprising:

2. The predetermined timing is after the occurrence of breakage of the test object in the material test or after the end of application of the test force.

2. A material testing machine according to claim 1.

3. the recording unit stores the test result and the still image for the test subject in the storage device as different files, and stores access information to the still image file in the test result file.

2. A material testing machine according to claim 1.

4. A fracture information acquisition unit that acquires an input of fracture information, which is information about a fracture position in the test object, The breakage information acquisition unit displays an input screen for the breakage information together with the acquired still image on a display device.

4. A material testing machine according to claim 1.

5. A material testing machine for performing a material test in which a test object is deformed by applying a test force to the test object, A fracture information acquisition unit that acquires fracture location classification information for the test object; a recording unit that associates the acquired fracture position classification with the test result of the test object in the material test and stores the result in a storage device; A material testing machine comprising:

Images