JPH0629714Y2 - Material testing machine - Google Patents

Description

Detailed Description of the Invention A. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material testing machine equipped with a multiple gripping device for use in a material testing machine that performs tensile tests and the like.

B. 2. Description of the Related Art Conventionally, a material testing machine shown in FIG. 3 has been known. This material testing machine has a pair of screw rods 3 rotatably rotatably supported in a crossing state between a cross yoke 2a horizontally mounted on a frame main body 2 erected on a base 1 and the base 1, Both ends of the crosshead 4 are screwed between the pair of screw rods 3 so as to be able to move up and down. An upper gripping tool 5 is connected to the middle of the crosshead 4 via a universal joint 6 and a load cell 7. Further, a lower gripping tool 8 on the base 1 is aligned with the upper gripping tool 5 in an axis line and a fixing tool 9 is provided. It is fixed by.

In the tensile test, both ends of the test piece 10 are gripped by the upper and lower grippers 5 and 8, and the screw head 3 is rotated by a motor (not shown) provided in the base 1 to raise the crosshead 4. , Load the test piece 10. When the tensile test of one test piece is completed, the upper and lower grips 5, 8 are opened to remove the tested test piece, and the untested test piece 10 is removed by the upper and lower grips 5, 8. Hold and perform the same tensile test as above.

On the other hand, in the constant temperature tensile test, the upper and lower gripping tools 5 and 8 configured in the same manner as in FIG. 3 are housed in the constant temperature tank 11 as shown in FIG. 4, and the test piece 10 is placed in the constant temperature tank 11. To load. At this time, the door 12 provided on the front surface of the constant temperature bath 11 so as to be opened and closed is closed.

C. Problems to be Solved by the Invention In the conventional constant temperature type material testing machine as described above, the door 12 is opened to carry the test pieces 10 one by one between the upper and lower grippers 5 and 8 during the constant temperature tensile test. However, it must be held in the proper position. For this reason, when testing a plurality of test pieces, the loading and gripping operations are complicated and the test efficiency is poor.

Further, in the tensile test, since the test piece 10 set in the constant temperature bath 11 is in the outside air temperature state, it takes time until the temperature of the test piece 10 set in the constant temperature bath 11 reaches the temperature in the constant temperature bath. Therefore, the test takt time becomes long, and the test efficiency decreases.

An object of the present invention is to provide a material testing machine equipped with a multiple gripping device that facilitates gripping operation of a plurality of test pieces and improves test efficiency.

D. Means for Solving the Problems A material testing machine equipped with a multiple gripping device according to the present invention comprises a gripping tool body having a base part and a gripping tooth mounting part connected to the material testing machine body, and a gripping tooth mounting part. A gripping tooth that is opened and closed to grip the test piece along the load axis, an opening / closing mechanism for the gripping tooth, and a support member that is provided through the space defined between the base and the gripping tooth. , A plurality of clips movably attached to the support member for respectively suspending the test piece, and a balance weight for offsetting at least a moment load acting on the gripping tool main body by the weight of the clip and the test piece held by the clip. Then, the gripped portion of the test piece suspended by the clip is configured to be positioned between the gripping teeth, thereby solving the above problem.

E. Action The test piece is held by a plurality of clips attached to the support member. Move this clip along the support member,
The test piece is positioned between the gripping teeth, and the test piece is gripped by the gripping teeth by operating the opening / closing mechanism. Therefore, the time required to grip a plurality of test pieces each time a test is shortened.
In addition, when this gripping device is installed in a constant temperature bath, the test piece held by the clip before the test is placed in the constant temperature bath, so there is no need for time to heat the test piece to the internal temperature during the test. Therefore, the test time is greatly reduced.

F. Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 (a), (b) and FIG.

In the figure, the multiple gripping device 20 constituting the material testing machine according to the present invention is used, for example, in place of the upper gripping tool 5 in FIG. 3, and is capable of holding a plurality of test pieces in advance.

The multiple gripping device 20 includes a connection base 2 to the material testing machine main body.
1a and a gripping tooth mounting portion 21b, a forked grip body 21, a pair of gripping teeth 22 provided on the gripping tooth mounting portion 21b at the tip thereof, and this pair of gripping teeth 22.
And an opening / closing mechanism including a pneumatic cylinder 23 for opening and closing. Further, the multiple gripping device 20 includes a balance weight rod 24 having a desired length, a balance weight 25 mounted on the balance weight rod 24, a test piece support rod (support member) 26 having a desired length, and Clip 27 for holding the test piece attached to the support rod 26
With.

The balance weight rod 24 penetrates through the opening (space) 21c of the grasping tool body 21 in the front-rear direction, and an intermediate portion thereof is horizontally supported by a support plate 31 fixed to the grasping tool body 21. Further, the balance weight 25 is movably attached to the balance weight rod 24 along the longitudinal direction thereof, and is fixed at a predetermined position by a tightening screw 32. The support rods 26 are arranged in parallel below the balance weight rod 24 with a predetermined separation therebetween, and both ends thereof are attached to the grasping tool main body 21 by suspending the both ends of the balance weight rod 24 by the support plates 33.

The clip 27 is provided for suspending the test piece TP on the support rod 26, and has a plate spring 27a formed in an isosceles triangular shape as shown in FIG. 2 and a protrusion provided at the center of the bottom portion of the plate spring 27a. A guide block 27b for mounting the support rod 26 movably in the longitudinal direction thereof and rotatable about its axis, and the apex portion 2 of the leaf spring 27a facing each other.
A test piece TP made of a rubber plate or other material is sandwiched between apexes 27e of the leaf spring 27a.

Next, the operation of this embodiment configured as described above will be described. The case of a constant temperature type tension test in which this multiple gripping device is installed in the constant temperature tank 11 shown in FIG. 4 will be described.

In the tensile test of the test pieces TP, first, all the clips 27 are pulled toward the door opening side of the thermostatic chamber 11, that is, the right side in FIG. 1B, and the test pieces TP are attached to all of these clips 27. Clip 2 holding test piece TP
7 along the support rod 26 in the depth direction of the constant temperature bath 11 (to the left in FIG. 1B), and as shown in FIG. The gripping device 20 is positioned on the load axis. At this time, the upper and lower end portions of the test piece TP suspended by the clip 27, that is, the gripped portions are between the pair of gripping teeth 22 of the multiple gripping device 20 and the gripping teeth of the lower gripping tool 8, respectively. 8a, 8
It is located between b (FIG. 3). Then, after closing the door of the constant temperature bath 11, when a gripping command is given from an external operation panel (not shown), the gripping teeth of the upper and lower gripping tools 20, 8 are closed by the movement of the pneumatic cylinder 23. The TP is gripped.

When the atmosphere in the constant temperature bath 11 reaches the set temperature, a motor (not shown) is activated to rotate the screw rod 3 to raise the crosshead 4 at a set speed to apply a tensile force to the test piece TP. As a result, the test piece TP is loaded and the desired test is performed.

After the tensile test is completed for one test piece, the door is opened to move the breaking test piece for which the tensile test is completed to the door side along the support rod 26, and the breaking test piece is removed from the clip 27. The untested test piece TP, which has been removed and held by another clip 27, is moved along the support rod 26 to the center of the upper and lower grippers 20, 8, that is, the load axis. After that, the door is closed, and as described above, the pneumatic cylinder 23
The upper and lower gripping tools 20, 8 are used to grip the upper and lower ends of the test piece TP by a pair of gripping teeth to perform a tensile test.

Hereinafter, the test piece TP held by the clip 27 in the constant temperature bath 11 is similarly repeated by repeating the above procedure.
Is sequentially moved to the load shaft cores of the upper and lower grippers 20, 8 and gripped to perform a tensile test.

Further, when a moment load is applied to the gripping tool main body 21 due to the weight of the test piece TP and the clip 27, the gripping tool main body 21 may tilt. In this case, the balance weight 25 was moved left and right along the balance weight rod 24 in FIG. 1B, and the position where the axis of the multiple gripping device 20 coincided with the load axis, that is, its inclination was corrected. Secure in position with the tightening screw 32. As a result, the moment load due to the weight of the clip 27, the test piece TP, and the like can be offset, a highly accurate test can be performed, and the test piece can be reliably gripped.

In the present embodiment as described above, the multiple gripping device 2
Since the test piece TP is held in advance by each clip 27 of 0, and the clip 27 is moved along the support rod 26 to the load axis of the upper and lower grippers 20, 8, the test to the grip position is performed. The setting of the piece TP becomes quick and easy. Further, in the test in the constant temperature bath, since the test piece TP before the tensile test is in the constant temperature bath 11,
The temperature of the test piece TP before the test is maintained at the ambient temperature of the constant temperature bath 11, and the time required to heat the test piece TP to the temperature in the constant temperature bath 11 becomes almost unnecessary. As a result, the takt time for the tensile test of the test piece TP can be shortened and the efficiency of the tensile test is improved.

The test piece TP previously suspended by the multiple gripping device 20
Is not limited to four.

Further, in the above embodiment, the method of arranging the test pieces TP in a straight line is described, but the support rod 26 may be formed in a ring shape. In this case, the balance weight 25 is
Gripping tool body 21 opposite to the side from which the ring-shaped support member projects
It is desirable to provide it on the side surface of.

Furthermore, the opening / closing mechanism of the gripping teeth 22 is not limited to the pneumatic type and may be a manual type, or may be an automatic type using pneumatic pressure or hydraulic pressure without manually moving the clip 27.
Further, although the constant temperature test has been described, it may be applied to the test in the normal temperature atmosphere as shown in FIG.

G. Effect of the Invention Since the present invention is configured as described above, setting the test piece at the gripping position becomes quick and easy, and its workability is improved. Especially in the test in a constant temperature bath, the test piece before being tested is in the constant temperature bath, so the time to heat the test piece to the temperature in the constant temperature bath becomes almost unnecessary, and the takt time of the tensile test is reduced. It can be shortened and the efficiency of the tensile test can be improved. In addition, the balance weight can cancel the moment load generated by the weight of the clip or the test piece, so that the test is not performed while the multiple gripping device is tilted, and the test piece is securely gripped and the accuracy is improved. High test is possible.

[Brief description of drawings]

FIG. 1 (a) is a front view showing a specific example of the multiple gripping device in the embodiment, FIG. 1 (b) is a side view of FIG. 1 (a),
FIG. 2 is a perspective view of the test piece holding clip 27 in the embodiment. FIG. 3 is a front view of a conventional material testing machine, FIG. 4 is a front view of a conventional constant temperature type material testing machine, and FIG. 5 is V- of FIG.
It is sectional drawing which follows the V line. 1: Base 2: Frame main body 3: Screw rod 4: Crosshead 5: Upper gripping tool 6: Universal joint 7: Load cell, 8: Lower gripping tool 10: Test piece, 11: Temperature chamber 21: Grasping tool main body, 22: Grip teeth 24: Balance weight rod 25: Balance weight 26: Support rod, 27: Clip

Claims (1)

[Scope of utility model registration request] 1. A gripping tool main body having a base connected to a material testing machine main body and a gripping tooth mounting portion, and a gripping tooth provided on the gripping tooth mounting portion and opened and closed to grip a test piece along a load axis. An opening / closing mechanism for the gripping teeth, a support member penetrating a space defined between the base portion and the gripping teeth, and a plurality of suspension members movably attached to the support member for respectively suspending test pieces. A clip, and a balance weight that offsets a moment load acting on the gripper main body by at least the weight of the clip and the test piece held by the clip, and the gripped portion of the gripped test piece of the test piece is held by the grip. A material testing machine equipped with a multiple-type gripping device, characterized in that it can be positioned between teeth.