JP2014126506A - Material testing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material testing machine which allows for easily placing a test piece in a test position even when applying test force on the test piece immersed in a liquid.SOLUTION: A test piece 11 is held by holding sections 44 of a pair of clips 43 below an upper platen 28, and then immersed in a liquid 52 pooled in a water tank 51. Next, operating sections of the pair of clips 43 located above a support member 42 are held together and moved closer to each other, causing the holding sections 44 of the pair of clips 43 to move away from each other. A substantially C-shaped fixing member 46 is then attached to the operating sections located above the support member 42 of the pair of clips 43. Thus, the pair of clips 43 is fixed in a release position for releasing the test piece 11.

Description

  The present invention relates to a material testing machine that performs a compression test by applying a test force to a test piece while the test piece is immersed in a liquid.

  In such a material testing machine, a lower platen is installed at the upper part of the bottom surface of the water tank, and a test piece is further installed on the lower platen, and then a liquid is injected into the water tank. Then, the test piece is sandwiched between the lower platen and the upper platen in the liquid stored in the water tank. Thereafter, the compression test is executed by applying a test force to the test piece held between the upper platen and the lower platen.

  Patent Document 1 discloses a test piece centering device for centering a test piece placed on a platen for a compression tester.

JP 2010-117224 A

  As described above, when adopting a configuration in which liquid is injected into the water tank after placing the test piece on the lower platen, it is necessary to perform liquid injection and temperature control each time the test piece is replaced. It takes a long time to run the test. Further, when the liquid is injected into the water tank after placing the test piece on the lower platen, there is a problem that the test piece is displaced due to the water pressure of the liquid. Further, when the specific gravity of the test piece is smaller than the specific gravity of the liquid, there arises a problem that the test piece floats on the surface of the liquid.

  For this reason, it is possible to position the test piece immersed in the liquid in the water tank with a hand or tweezers. However, when performing a material test using a high-temperature liquid, it is not only dangerous to perform such operations, but it is difficult to accurately visually check the position of the test piece in the liquid. Therefore, there arises a problem that it takes a long time to position the test piece.

  On the other hand, the test piece centering device described in Patent Document 1 is suitable for performing a general material test. However, a test force is applied to the test piece while the test piece is immersed in a liquid. Therefore, it is not applicable to a material testing machine that performs a compression test.

  The present invention has been made to solve the above-described problem, and even when a test force is applied in a state where the test piece is immersed in a liquid, the material can be easily placed at the test position. The purpose is to provide a testing machine.

  The invention according to claim 1 includes an upper platen, a water tank storing a liquid, and a lower platen immersed in the liquid stored in the water tank, and the upper platen in the liquid stored in the water tank. In a material testing machine that performs a compression test by applying a test force to a test piece sandwiched between the upper platen and the lower platen, the test piece that holds the test piece at a position between the upper platen and the lower platen A holding mechanism is provided.

  According to a second aspect of the present invention, in the first aspect of the present invention, the upper platen is attached to a crosshead that can be raised and lowered, and the test piece holding mechanism is connected to the upper platen to connect the upper platen. Move up and down with the platen.

  The invention according to claim 3 is the invention according to claim 2, wherein the test piece holding mechanism is movable between a holding position for holding the test piece and a release position for releasing the test piece. A pair of clips is provided.

  According to a fourth aspect of the present invention, in the invention according to the third aspect, the operation area of the pair of clips is stored in the water tank when the test piece is sandwiched between the upper platen and the lower platen. The liquid is disposed above the liquid level.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the biasing member that biases the clip toward the holding position and a fixing member for fixing the clip to the release position. Further prepare.

  The invention according to claim 6 is the invention according to any one of claims 2 to 5, wherein the test piece holding mechanism is connected to the upper platen so as to be movable in the vertical direction.

  According to the first aspect of the invention, even when the test force is applied in a state where the test piece is immersed in the liquid, the test piece is easily held at the test position by holding the test piece by the test piece holding mechanism. It becomes possible to arrange in. For this reason, it becomes possible to perform a compression test efficiently.

  According to the second aspect of the present invention, the test piece is supported below the upper platen by the test piece holding mechanism above the water tank, and this test piece can be placed in the water tank together with the upper platen.

  According to invention of Claim 3, it becomes possible to hold | maintain a test piece using a pair of clip, or to cancel | release holding | maintenance of a test piece.

  According to the fourth aspect of the present invention, it is possible to execute the opening / closing operation of the clip without touching the liquid.

  According to the fifth aspect of the present invention, when the test piece is arranged at the test position, the holding of the test piece can be continued, and during the compression test, the holding of the test piece is released to increase the holding force to the test piece. By opening, it becomes possible to prevent the holding force from affecting the test result.

  According to the invention described in claim 6, the test piece can be suitably held regardless of the size of the test piece, and the clip is placed in an appropriate height position so that the clip becomes an obstacle to the compression test. Can be prevented.

1 is a schematic diagram of a material testing machine according to the present invention. It is a front view which shows the state which hold | maintained the test piece 11 with the test piece holding mechanism above the water tank 51. FIG. It is a side view which shows the state which hold | maintained the test piece 11 with the test piece holding mechanism above the water tank 51. FIG. It is a front view which shows the state which performs a compression test in the water tank 51. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a material testing machine according to the present invention.

  This material testing machine performs a compression test by compressing the test piece 11 with the upper platen 28 and the lower platen 29, and is screwed into the pair of left and right screw rods 23 and the pair of left and right screw rods 23. A crosshead 26 that includes a nut portion and moves up and down with respect to the screw rod 23 is provided. An upper platen 28 is disposed on the cross head 26. On the other hand, a water tank 51 that stores liquid is disposed on the table 21, and a lower platen 29 is disposed in the water tank 51. The upper and lower ends of the test piece 11 to be subjected to the compression test are pressed by the upper platen 28 and the lower platen 29 in the liquid stored in the water tank 51. The upper platen 28 is provided with a test piece holding mechanism according to the present invention, as will be described later.

  Synchronous pulleys 36 that engage with the synchronous belt 22 are disposed at the lower ends of the pair of screw rods 23. The synchronous belt 22 is also engaged with a synchronous pulley 34 that rotates by driving of a motor 35. For this reason, the pair of screw rods 23 rotate in synchronization with the drive of the motor 35. Then, when the pair of screw rods 23 rotate in synchronization, the cross head 26 moves up and down in the axial direction of the pair of screw rods 23.

  Next, the configuration of the test piece holding mechanism which is a characteristic part of the present invention will be described. FIG. 2 is a front view showing a state in which the test piece 11 is held by the test piece holding mechanism above the water tank 51. FIG. 3 is a side view showing a state in which the test piece 11 is held by the test piece holding mechanism above the water tank 51. FIG. 4 is a front view showing a state in which the compression test is executed in the water tank 51.

  The test piece holding mechanism includes a pair of clips 43 that are swingable about a shaft (not shown) disposed on the support member 42, a pair of butterfly bolts 41 for fixing the support member 42 to the upper platen 28, And a spring 45 that urges the upper ends of the pair of clips 43 in directions away from each other. A holding portion 44 for holding the test piece 11 is formed at the lower ends of the pair of clips 43. This test piece holding mechanism is movable in the vertical direction with respect to the upper platen 28 by loosening the butterfly bolt 41.

  When the test piece 11 is held by the test piece holding mechanism, the holding portion 44 in the clip 43 is moved by the spring 45 by gripping the operation area above the support member 42 in the pair of clips 43 and moving it in the direction of approaching each other. They are moved away from each other against the urging force of. And the holding part formed in the lower end part of a pair of clip 43 by the effect | action of the spring 45 by releasing the holding state of the operation area | region in a pair of clip 43 in the state which has arrange | positioned the test piece 11 below the upper platen 28. 44 are moved in directions close to each other. Thereby, as shown in FIGS. 2 and 3, the test piece 11 is held by the holding portion 44 in the pair of clips 43 below the upper platen 28.

  Next, an operation when a compression test is executed by a material testing machine having such a test piece holding mechanism will be described.

  When performing the compression test, the lower platen 29 is disposed in the water tank 51 and the liquid 52 is stored in the water tank 51. As the liquid 52, for example, when an artificial bone disposed in the human body is used as the test piece 11, physiological saline or the like is used. In addition, various chemical solutions and high-temperature liquids are used in response to the compression test performed on the test piece 11. Then, the water tank 51 storing the liquid 52 is placed on the table 21. At this time, the cross head 26 is raised, and the upper platen 28 and the test piece holding mechanism are disposed above the liquid 52 stored in the water tank 51.

  In this state, the test piece 11 is held by the test piece holding mechanism. In this case, as described above, by holding the operation region above the support member 42 in the pair of clips 43 and moving them in a direction in which they are close to each other, the holding portion 44 in the clip 43 is placed in a separated state. By opening the gripping state of the operation area in the pair of clips 43 with the test piece 11 disposed between them, the pair of clips is placed below the upper platen 28 as shown in FIGS. It is held by the holding portion 44 at 43.

  Next, the cross head 26 is lowered, and the test piece 11 is immersed in the liquid 52 stored in the water tank 51 together with the upper platen 28 and the test piece holding mechanism. Then, the lowering of the cross head 26 is stopped at a position where the lower end portion of the test piece 11 comes into contact with the lower platen 29 placed in the water tank 51. As a result, the test piece 11 is sandwiched between the upper platen 28 and the lower platen 29.

  Although it is possible to execute a compression test in this state, the holding force of the pair of clips 43 to the test piece 11 may affect the result of the compression test. For this reason, the holding force to the test piece 11 by the pair of clips 43 is released. In this case, the holding portion 44 in the clip 43 is moved in a direction away from each other by grasping the operation area above the support member 42 in the pair of clips 43 and moving the operation area in a direction close to each other. After that, as shown in FIG. 4, a substantially C-shaped fixing member 46 is attached to the operation region above the support member 42 in the pair of clips 43. Thereby, as shown in FIG. 4, a pair of clip 43 is fixed in the release position which open | releases the test piece 11. As shown in FIG.

  Then, the screw head 23 is rotated by driving the motor 35 to lower the cross head 26, and a compressive load is applied to the test piece 11 disposed between the upper platen 28 and the lower platen 29 to perform a compression test. Run.

  When the compression test is completed, the fixing member 46 is removed from the pair of clips 43, and the test piece 11 is held by the holding portion 44 in the pair of clips 43. Then, the cross head 26 is raised, and the upper platen 28 and the test piece holding mechanism are disposed above the liquid 52 stored in the water tank 51. Thereafter, the operation region above the support member 42 in the pair of clips 43 is gripped, and the holding portions 44 in the clips 43 are moved away from each other, thereby removing the test piece 11.

  When the size of the test piece 11 in the vertical direction is changed, the position of the test piece holding mechanism may be adjusted in the vertical direction with respect to the upper platen 28 after loosening the butterfly bolt 41. If there is a possibility that the lower ends of the pair of clips 43 may come into contact with the lower platen 29 during the compression test, the butterfly bolt 41 is loosened and the entire specimen holding mechanism is moved upward before the compression test is executed. You just have to evacuate.

  In the above-described embodiment, the pair of clips 43 are manually moved between the holding position for holding the test piece 11 and the release position for opening the test piece 11. You may make it move between a holding position and a releasing position by driving.

  In the above-described embodiment, the test piece holding mechanism is directly connected to the upper platen 28. However, if the test piece holding mechanism can be moved up and down together with the upper platen 28, the upper part is interposed via other members. The platen 28 may be connected.

DESCRIPTION OF SYMBOLS 11 Test piece 21 Table 22 Synchronization belt 23 Screw rod 26 Cross head 28 Upper platen 29 Lower platen 34 Synchronous pulley 35 Motor 36 Synchronous pulley 41 Butterfly bolt 42 Support member 43 Clip 44 Holding part 45 Spring 46 Fixing member 51 Water tank 52 Liquid

Claims (6)

An upper platen, a water tank storing liquid, and a lower platen immersed in the liquid stored in the water tank, and sandwiched between the upper platen and the lower platen in the liquid stored in the water tank In a material testing machine that performs a compression test by applying a test force to a test piece,
A material testing machine comprising a test piece holding mechanism for holding the test piece at a position between the upper platen and the lower platen. The material testing machine according to claim 1,
The upper platen is attached to a cross head that can be raised and lowered,
The test piece holding mechanism is a material testing machine that is connected to the upper platen and moves up and down together with the upper platen. The material testing machine according to claim 2,
The test piece holding mechanism is a material testing machine including a pair of clips movable between a holding position for holding the test piece and a release position for releasing the test piece. The material testing machine according to claim 3,
A material testing machine in which an operation region in the pair of clips is disposed above a liquid level of a liquid stored in the water tank when the test piece is sandwiched between the upper platen and the lower platen. The material testing machine according to claim 4, wherein
A biasing member that biases the clip toward the holding position;
A fixing member for fixing the clip in the release position;
A material testing machine further comprising: In the material testing machine according to any one of claims 2 to 5,
The test piece holding mechanism is a material testing machine connected to the upper platen so as to be movable in the vertical direction.

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