JP3291209B2 - Plate strength tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for examining the strength of a plate-like body such as a flooring material.

[0002]

2. Description of the Related Art A so-called free access floor has been widely used in order to meet a demand for an increase in the degree of freedom of underfloor wiring accompanying the OA. In this case, a floor plate is floated from a floor base material such as a slab. Since it is installed in a state, the strength of the floorboard becomes a problem. This is because a load of several hundred kg may be applied to the floorboard, for example, when running a cart full of papers.

[0003] For this reason, a floor plate for a free access floor, which is mounted on a column having four corners standing upright from a floor base material, is made of a high-strength steel plate. As shown in FIG.
And a wheel 92 is mounted in the middle of the lever 9 having a weight 91 suspended from the other end, and a load by the weight 91 is applied to the test body 8 as a floor plate.

[0004]

However, the above-mentioned strength test merely examines the strength under static load, and does not reflect the load when the bogie is actually running on the floorboard. Nor can it be used to determine the exact characteristics of the floorboard in terms of durability. It is conceivable to move the floorboard left and right in order to perform the test under dynamic load. However, since the displacement of the floorboard cannot be measured without stopping the floorboard, there are many problems in the strength test.

The present invention has been made in view of the above points, and an object of the present invention is to provide a plate-like body strength test apparatus capable of accurately examining the strength of a plate-like body such as a floor plate. To be.

[0006]

According to the present invention, there is provided an apparatus for testing the strength of a plate-like body, comprising: a supporting means for supporting a plate-like specimen; and a load means comprising a rotating body for applying a set load to the surface of the specimen. Driving means for moving the load means along the surface of the test object; displacement amount measuring means for measuring the displacement amount of the test object due to the load means and the load given by the drive means; and recording means for recording the displacement amount measured by the load value and the displacement amount measuring means, the load hands
The stage is an air cylinder connected to a pressure reducing valve for fine adjustment of the load.
-Or set the load with a hydraulic cylinder through a rotating body.
To the specimen, and the cylinder is
A first circuit for applying a static load to the specimen;
A second circuit for applying a dynamic load is switchably connected to the second circuit.
It has the feature that it is the thing which was done. Durable strength all SANYO test can be performed, although the reduced pressure valve for fine adjustment of the load means load contact in the state plus the dynamic load to the test specimen
The air cylinder or hydraulic cylinder
Because a constant load is applied to the test specimen via the rotating body
If it becomes easy to adjust or change the load applied to the specimen,
Can be performed accurately, ensuring safety in the workplace
This makes it easier to use
A first circuit for applying a static load to the specimen;
A second circuit for applying a dynamic load is switchably connected to the second circuit.
Test for both static and dynamic load tests.
Can be tested.

At this time, a setting unit for setting a load value to be applied to the test object by the load means and the number of times the rotating body moves on the test object in a state where the load is applied, and the setting unit for setting the value. If a control means for operating the load means based on the load value and the number of movements is provided, the durability test can be performed unattended, and the strength test can be performed without any trouble.

The recording means is preferably a computer provided with a program for outputting the measurement results as a table or a graph. It becomes easy to grasp the test results .

[0009] The driving means preferably is a speed control for moving the rotary body along the surface of the test specimen those freely.

It is preferable that the driving means comprises a timing belt having both ends connected to the load means, and a servomotor for rotating a timing pulley around which the timing belt is wound. Since the load means is supported by the linear guide in the moving direction of the drive means, it is possible to reliably receive the load reaction force during the movement and reduce the size.

If the rotating body is attached to the load member with a small play in the load application direction and in a direction perpendicular to the load application direction, the load can be transmitted reliably. It is also preferable to provide a detection member for warning a load failure due to insufficient stroke of the load unit. A situation in which a desired load cannot be applied does not occur.

If an overrun preventing means for preventing an overrun of the movement by the driving means is provided,
Unforeseen situations will not lead to accidents. It is preferable that the support means can be changed according to the type of the test body. Tests can be performed on various types of specimens.
A wall material surrounding the test body, the load means, the driving means and the support means is provided, and among the wall materials, a wall material surrounding the test space in which the test body is arranged is formed of a transparent plate, so that during the test, The state can be visually checked.

[0013] A power supply member for the test object may be provided in the test space. In this case, the test object is an electric product and can respond to a case where the test is to be performed in a state where power is supplied. Become. If a mirror for reflecting the back surface of the test object floating and supported by the support means is provided in the test space, the position where the displacement meter is brought into contact with the back surface of the test object can be easily determined.

It is also preferable to provide a space for storing accessories.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an embodiment of the present invention will be described. A gantry 1 which is framed by a type steel material such as a C-type steel and has an internal space divided into three layers of upper, middle and lower parts.
The middle space is a test space in which the test specimen 8 to be subjected to the strength test is arranged.
As shown in FIG. 1, a door 10 is provided, and a drawer 11 for accommodating accessories and the like of the strength test device is provided on the lower front surface.
It is covered with 2. The door 10 and the plate 1 surrounding the test space
2, at least the front part, that is, the door 10 is formed of a transparent plate such as a transparent acrylic plate so that the test space can be seen through.
The door 10 is configured by a sliding door (four consecutive sliding doors in the illustrated example) so that opening and closing of the door 10 does not require a large space on the front side of the gantry 1 and each door 10 is an individual sliding door. In addition to being able to open only an arbitrary door 10 by being arranged in a groove, if all four doors 10 are moved to one side in the illustrated example, the four doors 10 overlap one another,
The front of the test space can be greatly opened.

A steel plate is provided on the floor of the test space, so that a support base 15 serving as a support means can be fixed at an arbitrary position with bolts or the like. Then, the flat plate-like test body 8 such as a floor material is placed on the support table 15 and disposed in the test space. Support table 15 here
Is such that the upper surface of the specimen 8 is horizontal.
The height of which can be adjusted by a spacer or the like so that the upper surface can be arranged at a predetermined height or higher from the floor of the test space.

When the specimen 8 is a floor plate for a free access floor as described above, the four corners of the specimen 8 are placed on the support 15 as shown in FIG. . In the illustrated example, three specimens 8 are arranged on the left and right. However, it is the central specimen 8 that is actually subjected to the strength test. This is for more accurate reproduction.

A loading means 2 is disposed above the test space. As shown in FIGS. 1 and 4, the load means 2 is attached to the lower surface of the die steel material of the gantry 1 before and after running in the left-right direction via linear guides 29, 29 so as to be movable in the left-right direction. The upper plate 22, the lower plate 23 on which the rotating body 20 that travels on the upper surface of the test body 8 is attached to the lower surface, and the lower plate 23 fixed to the upper surface of the upper plate 22 and project below the upper plate 22. Air cylinder 21 whose shaft end is connected to lower plate 23 via floating connector 25
And a plurality of linear guides 24 for guiding the vertical movement of the lower plate 23 with respect to the upper plate 22. The connection between the floating connector 25 and the lower plate 23 is such that the floating connector 25 is fixed to the upper surface. The upper ends of a plurality of columns 27 erected from the lower plate 23 are attached to the fixed plate 26. However, as shown in FIG. 5 (a), the fixed plate 26 and the support column 27 have a small play α in the vertical direction, and a load detecting member is provided between the lower surface of the fixed plate 26 and the upper surface of the lower plate 23. Are provided.

Further, as shown in FIG. 5 (b), the shaft end 24a fixing the lower end of the shaft of the linear guide 24 to the lower plate 23 can be released by loosening the bolt 24b. The fixing between the support 27 and the fixing plate 26 can be released by loosening the nut. This is to facilitate replacement of the lower plate 23 on which the rotating body 20 is arranged on the lower surface. In addition, in FIG.
A state in which the lower plate 23 having only one 0 is mounted,
FIG. 2 shows a state in which a lower plate 23 having three rotating bodies 20 is mounted.

The load means 2 constructed as described above operates the air cylinder 21 to extend its shaft, whereby the lower plate 23 descends and the rotating body 20 is moved to the test body 8 installed as described above. The load can be measured by the load cell 40. The floating connector 25 has a ball disposed between members connected to each other in the upper and lower directions. The floating connector 25 can reliably load even if the center between the air cylinder 21 and the rotating body 20 is slightly shifted in a direction orthogonal to the direction in which the load is applied. It is provided so that it can be transmitted to.

As shown in FIG. 7, the rotating body 20 has a lining 20b of urethane rubber on the outer peripheral surface of an iron wheel 20a.
A vertical shaft 28a penetrating the lower plate 23, as shown in FIG.
It is mounted on the lower plate 23 via a mounting frame 28b whose vertical movement is guided by a guide 23a arranged on the lower surface. Then, as is apparent from the position of the stopper 28c attached to the upper end of the vertical shaft 28a, the lower plate 23
And the floating connector 25 allows the load applied by the air cylinder 21 to be applied to the test body 8 by the rotating body 20 without being affected by the lower plate 23. And the load can be accurately applied to the load cell 40.
It can be measured with.

The proximity switch 45 shown in FIG. 4 mounted on the upper plate 22 is turned on and off by a magnet 46 mounted on the lower plate 23, and applies a sufficient load to the test body 8 in the vertical stroke by the air cylinder 21. It is activated when the lower plate 23 is lowered to a position where the test piece 8 cannot be installed, and outputs an output for warning that the installation height of the test body 8 is insufficient.

The load means 2 is movable in the left-right direction by the linear guide 29 as described above.
Both ends of a timing belt 32 that is bridged between a pair of timing pulleys 33 provided on both right and left ends of the gantry 1 are fixed to the load unit 2. An AC servo motor 30 with a speed reducer is connected to one of the timing pulleys 33. The driving of the timing pulley 33 by the motor 30 causes the load means 2 to move left and right in the gantry 1 and to move the motor controller 31
The load means 2 reciprocates within a predetermined range by the driving means 3 so that the motor 30 reverses the rotation direction when the motor 30 reaches a predetermined position.

The predetermined range of the reciprocating movement is controlled by a limit switch, a proximity switch, or the counting of output pulses from an encoder attached to the motor 30, and is limited to, for example, a range L in FIG. . When the motor controller 31 moves the load means 2 at the initial position, the motor controller 31 changes the count number C1 according to the count number of the output pulse as shown in FIG.
Until the number of revolutions gradually increases, and then the count number C
The rotation speed is kept constant up to 2, and the rotation speed is gradually decreased during the count number C3 to stop the rotation. Next, the rotation direction is reversed to perform the same rotation speed control. The initial position after the power is turned on is set by disposing a switch such as a limit switch at the initial position and moving the load unit 2 until the load unit 2 operates the switch. The motor 30 and the timing pulleys 33 in the driving means 3 are housed in the upper space of the gantry 1 and are not directly visible from the outside.

The displacement of the test body 8 is measured by one or a plurality of displacement meters 41 disposed at an arbitrary position on the floor of the test space via a magnet stand 42.
The displacement meter 41, which measures a displacement amount when the test body 8 is bent or deformed by receiving a load by applying a measuring needle to the back surface of the test body 8, is mounted on the back surface of a place where the displacement of the test body 8 is to be measured. Arrange so that the measuring needle touches it. At this time, if a mirror 18 is installed in the lower part of the lower part of the test space as shown in FIG.
It is easy to install the displacement meter 41 at a required position. In addition, the mirror 18 is also capable of illuminating the back surface of the test body 8 with the illumination 19 installed above the test space.

FIG. 8 shows an electric circuit block. The load cell 40 is connected to a personal computer (hereinafter referred to as a personal computer) 50 via a display controller 53 and a sequencer 32, and the displacement meter 41 is connected to the sequencer 32 and the personal computer 50. In the figure, 43 is a load means 2
A switch 44 is provided at a position beyond the both ends of the moving range L of the load device 2 to detect an overrun of the load means 2, and a switch 44 detects the opening and closing of the door 10; For example, when is opened, the sequencer 32 immediately stops the test by the output of these switches 43 and 44. In the figure, 51 is a monitor for the personal computer 50, and 52 is a printer for outputting test results.

The air cylinder 2 in the loading means 2
1 operates with compressed air supplied from a compressor (not shown). The supply of air to the air cylinder 21 is increased by a system via a pressure reducing valve 62A as shown in FIG. Two systems of the system via the pressure device 63 and the pressure reducing valve 62B are selectively used by switching by the solenoid valves 61A and 61B. The former system is for observing the displacement of the test body 8 under a dynamic load, and the latter system is for observing the displacement of the test body 8 under a static load. The latter system is also provided with a pressure intensifier 63 in order to apply a load approximately twice as large as the case of a dynamic load. When performing a strength test with a static load, it is preferable to use a separate bracket instead of the rotating body 20. Although the air cylinder 21 is shown here, a hydraulic cylinder may be used. In this case, it is preferable to configure a hydraulic circuit similar to the above using a pressure reducing valve for fine adjustment of the load. .

The personal computer 50 controls the operation of the load means 2 including the valves in the air pipe and the drive means 3 via the sequencer 32, and captures and outputs the outputs of the load cell 40 and the displacement meter 41. In addition, a program that can output the recorded data in the form of a table or a graph as a measurement result is incorporated. Further, a display unit for displaying the load measured by the load cell 40 and a display / operation device 53 capable of performing a touch panel type input are provided with a keyboard connected to the personal computer 50.
And is provided on the upper front surface of the gantry 1.

In the strength test apparatus configured as described above, when performing the durability test for the dynamic load of the test body 8, the door 10 of the gantry 1 is first opened, and the test body 8 is set in the test space. At this time, since the floor surface of the test body 8 and the linear guide 29 which is the traveling guide of the load means 2 are parallel to each other, and the gantry 1 is installed so that they are horizontal, the test is performed. The height of the plurality of supports 15 is adjusted so that the body 8 is parallel to the floor surface or the level of the upper surface of the test body 8 is horizontal using a level or the like. Then, the displacement gauge 41 is connected to the magnet catch 4
2 is used to fix the position where the displacement is to be measured, and the measuring needle is brought into contact with the back surface of the test body 8.

Next, the power of the strength test apparatus including the personal computer 50 is turned on, and test conditions such as the number of times of running, the running speed, the number of measurements, the measuring speed, and the like are set from the display / operation device 53. The number of measurements and the measurement speed are set so that the displacement is not measured and recorded at all times, but is measured and recorded every several runs. Is set to be faster, so that the load means 2 travels at a speed corresponding to the case where an actual load is applied at the time of measurement. In addition, the output itself of the displacement meter 41 is constantly monitored, and if the displacement becomes larger than a certain degree, the output of the displacement meter 41 is recorded regardless of the number of measurements and the setting of the measurement speed. In addition, it is not possible to record the displacement when the test body 8 is broken or plastically deformed by the load.

On the personal computer 50 side, a corresponding program is started, and various inputs such as a recording file name, a name of the specimen 8, a measurement location, and a connection channel of the displacement meter 41 corresponding to the measurement location are performed in response to an inquiry. Further, zero reset is performed for all the displacement meters 41. Thereafter, an offline measurement operation is performed. That is, the rotating body 20 is lowered by operating the air cylinder 21 of the load means 2 at one end of the reciprocating stroke, and is brought into contact with the test body 8. Then, the load value is read by the display / operation device 53, and the load is finely adjusted by operating the pressure reducing valve 62A. And the rotating body 2
0 is pressed against the test piece 8, the load means 2 is moved to the other end of the reciprocating stroke, and the load value is again displayed on the display / operation device 53.
And fine adjustment of the load is performed by operating the pressure reducing valve 62A.

When the various settings are completed in this way, the durability test is started, and the operation in which the rotating body 20 applying a desired load to the test body 8 rolls on the upper surface of the test body 8 is repeated. Let This load causes the test body 8 to bend as shown in FIG. 11, but the displacement δ due to the deflection is measured by the displacement meter 41, and the load value, the amount of displacement, the number of times of travel, and the displacement of the rotating body 20 at the time of the displacement measurement are measured. The running position and the like are recorded by the personal computer 50.

When the reciprocating motion of the load means 2 reaches the set number of running times, the test is automatically stopped. If the test piece 8 is broken or plastically deformed on the way, the displacement change at this time is recorded and the running of the load means 2 is stopped as described above. When the load means 2 moves beyond the set traveling range, the output of the overrun detection switch 43 is stopped to stop the test, and the solenoid valve in the air supply path to the load means 2 is stopped. The rotating body 20 is raised by switching 61A. In addition, the same operation is performed for safety when the door 10 is opened while the load unit 2 is running during the test.

Although the floor panel for the free access floor is shown as the test body 8, it is needless to say that other building materials may be used, and also that a plastic molded article having a form as shown in FIG. A test is possible, and a strength test of an electric carpet or the like is also possible by using the corresponding support 15 as shown in FIG. When the test body 8 is used by being energized like an electric carpet, a power outlet 17 may be prepared in the test space.

[0035]

As described above, according to the present invention, a supporting means for supporting a flat test piece, a load means having a rotating body for applying a set load to the surface of the test piece, A driving means for moving along the surface, a displacement measuring means for measuring a displacement of the test body due to the load given by the loading means and the driving means, a load value given by the loading means and the displacement measuring means Since it has a recording means for recording the measured displacement amount, it is possible to perform a durability strength test in a state where a dynamic load is applied to the specimen, and accurately evaluate the strength of the specimen. Is what you can do. In addition, a pressure reducing valve for fine adjustment of the load is connected.
Rotate the set load with the cylinder or hydraulic cylinder.
When using a weight to give the specimen through the
It is easier to adjust and change the load applied to the specimen than
It is possible to apply a precise load to the specimen
In terms of safety on the surface,
The cylinder above is used to apply a static load to the specimen.
A first circuit and a second circuit for applying a dynamic load to the specimen.
Because the road and the road are switchably connected, the static load test and
Both the dynamic load test and the test can be performed selectively
In addition, both tests can be easily switched
It is.

A setting unit for setting a load value to be applied to the test body by the load means and the number of times the rotating body moves on the test body in a state in which a load is applied; and a load value and a load value set by the setting unit. If the apparatus is provided with control means for operating the load means based on the number of movements, the above-mentioned durability strength test can be performed unattended, so that a long-term durability test can be performed without requiring any trouble. .

If the recording means is a computer having a program for outputting the measurement results as a table or a graph, it is possible to obtain the test results in a form that makes it easy to grasp the test results, and it is necessary to separately perform data processing later. And not .

[0038] The drive means is preferably the speed control to move the rotary body along the surface of the test specimen those freely, in this case, on the can or avoid the occurrence of vibration and unpleasant sound In addition, the acceleration test can be smoothly performed, and the size and weight of the test apparatus itself can be reduced.

When the driving means is constituted by a timing belt having both ends connected to the load means and a servomotor for rotating the timing pulley around which the timing belt is stretched, the driving means can be obtained with simple equipment. . Furthermore, by keeping the load means supported by the linear guide in the moving direction of the drive means, the load means can be smoothly moved and the load reaction force during the movement can be reliably received,
Furthermore, size reduction can be achieved.

When the rotating body is attached to the load member with a small play in the load application direction and in a direction perpendicular to the load application direction, the load can be reliably transmitted, and The measurement of the load can also be performed accurately. By providing a detection member for warning a load failure due to insufficient stroke of the load unit, it is possible to prevent a situation where a desired load cannot be applied.

If an overrun preventing means for preventing the overrun of the movement by the driving means is provided, an emergency stop or the like can be performed even in an unexpected situation, and a major accident does not occur. By making the supporting means freely changeable according to the type of the specimen, it is possible to perform tests on various specimens.

When a wall material surrounding the test body, the load means, the driving means and the support means is provided, and among the wall materials, a wall material surrounding the test space in which the test body is arranged is formed of a transparent plate. The state during the test can be visually checked. If the power supply member for the test object is provided in the test space, it is possible to respond to a case where the test object is an electric product and a test is desired to be performed in a state where power is supplied.

If a mirror is provided in the test space for reflecting the back surface of the test object floating and supported by the support means, it is easy to determine the contact position when the displacement meter comes into contact with the back surface of the test object. The time required for test preparation can be reduced. By providing a storage space for accessories, it is possible to eliminate the loss of accessories and to prepare the surroundings of the test apparatus.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of an embodiment of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is a perspective view showing the appearance of the above.

FIG. 4 is a transverse cross-sectional view of the load means.

FIG. 5 (a) is a partially cutaway front view of the above-mentioned load means, and FIG.
2 is a horizontal sectional view of a part of the above.

6A and 6B show a mounting portion of the rotating body of the above, wherein FIG. 6A is a cutaway front view and FIG. 6B is an enlarged sectional view.

FIG. 7 is a cross-sectional view of the rotating body of the above.

FIG. 8 is a circuit block diagram of the above.

FIG. 9 is a schematic piping diagram of the above.

FIG. 10 is a flowchart of a test operation of the above.

FIG. 11 is an operation explanatory diagram of the above.

FIG. 12 is an explanatory diagram of an operation of a motor of the driving means according to the embodiment.

FIG. 13 is a schematic cross-sectional view of another example of the above.

FIGS. 14A and 14B show another example of a test body and a support table, and FIGS.
Are both front views.

FIG. 15 is a schematic front view of a conventional example.

[Explanation of symbols]

 2 Loading means 3 Driving means 8 Specimen 40 Load cell 41 Displacement meter

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shigeichi Shimotsu 10-24 Hinoide-cho, Neyagawa-shi, Osaka Horita Iron Works Co., Ltd. (72) Inventor Masataka Hattori 10-24 Hinode-cho, Neyagawa-shi, Osaka Hotta (56) References JP-A-5-332907 (JP, A) JP-A-1-297526 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 3/20 JICST file (JOIS)

Claims (14)

(57) [Claims] 1. A supporting means for supporting a plate-shaped test body,
Load means having a rotating body for applying a set load to the surface of the test piece, drive means for moving the load means along the surface of the test piece, and displacement of the test piece due to the load means and the load given by the drive means Measuring means for measuring the displacement amount, and a recording means for recording the load value given by the load means and the displacement amount measured by the displacement amount measurement means , the load means
Air cylinder with pressure reducing valve for fine adjustment of load
Or set load with hydraulic cylinder through rotating body.
To be given to the specimen, and the cylinder is the specimen
A first circuit for applying a static load to
A second circuit for adding weight is switchably connected.
An apparatus for testing the strength of a plate-like body, characterized in that the apparatus is a test piece. A setting unit for setting a load value to be applied to the test object by the load means and a number of times the rotating body moves on the test object under a load, and a load set by the setting unit. 2. The apparatus according to claim 1, further comprising control means for operating the load means based on the value and the number of movements. 3. The apparatus according to claim 1, wherein the recording means is a computer having a program for outputting the measurement results as a table or a graph. 4. The driving means includes a rotating body along a surface of the test body.
It is characterized by the ability to control the speed of moving
The plate-like body strength test device according to any one of claims 1 to 3 . 5. The driving means has both ends connected to the load means.
Timing belt and the timing belt
Servo motor that rotates the timing pulley
5. The apparatus for testing the strength of a plate-like body according to claim 1, wherein the apparatus comprises: 6. The load means is reset in the direction of movement by the drive means.
A contract that is supported by a near guide
The plate-like body strength test device according to any one of claims 1 to 5 . 7. The rotating member is configured to apply a load to a load member in a direction in which a load is applied.
And a small play in the direction orthogonal to the direction of load application.
2. The electronic device according to claim 1, wherein the electronic device is mounted in a state where the electronic device is mounted.
7. The apparatus for testing the strength of a plate-shaped body according to any one of claims 6 to 6 . 8. A load failure due to insufficient stroke of the load means.
It is equipped with a detection member for good warning
An apparatus for testing the strength of a plate-like body according to any one of claims 1 to 7 . 9. An overrun of the movement by the driving means is prevented.
It is characterized by having overrun prevention means to stop
The apparatus for testing the strength of a plate-like body according to any one of claims 1 to 8 . 10. The support means is changed according to the type of the test piece.
10. Any of claims 1 to 9, characterized in that it is free.
An apparatus for testing the strength of a plate-like body according to any one of the claims . 11. A test body, load means, drive means, and support.
A wall material surrounding the means;
The wall material surrounding the test space where the body is placed is formed of a transparent plate
The method according to any one of claims 1 to 10, wherein
A plate-like body strength testing device. 12. A power supply member for a test body is provided in a test space.
The apparatus for testing the strength of a plate-like body according to claim 11, characterized in that: 13. Floating and supported by supporting means.
There must be a mirror in the test space to reflect the back of the test specimen.
The plate-like body strength test device according to claim 11, characterized in that: 14. A storage space for accessories is provided.
The apparatus for testing the strength of a plate-like body according to claim 11, characterized in that: