JPH01242936A - Material testing machine - Google Patents

Abstract

PURPOSE:To make a load axis hard to become eccentric, to conduct a test accurately and excellently, and to increase the mechanical strength of the testing machine by providing >=3 fixed columns vertically on the base board of a load main body. CONSTITUTION:The fixed columns 4 are provided vertically at the positions of the four corners of the base board 1. Further, a movable base 2 mounted on the base board 1 is constituted integrally with an elevation table 3 united with a ram 17 which is moved up and down by a hydraulic cylinder 16 installed on the base board 1. Further, movable columns are provided vertically on the elevation table 3 on both sides between the respective fixed columns 4, a lower cross head 6 is fixed and held in an elevation state on the four fixed columns 4 and an upper cross head 7 is fixed to the upper ends of the movable columns. Then when hydraulic pressure is applied to the hydraulic cylinder 16, a sample held by both jigs 10 and 11 is compressed and tested between the elevation table 3 and lower cross head 6, and the tension of a sample clamped by both chucks 12 and 13 is tested between both cross heads 6 and 7.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application This invention relates to a load body of a material testing machine that can perform compression tests and the like to determine buckling characteristics.

B. Prior Art This type of compression test uses a universal testing machine capable of carrying a large load. The load body of the universal testing machine is, for example,
As shown in Publication No. 1-61336 "Crosshead Lifting Device for Material Testing Machine", two fixed columns are suspended above a fixed head (base) installed on the floor, and a hydraulic loading mechanism is installed. Further, an elevating column is installed vertically above the elevating table on the hydraulic load mechanism. The fixed columns and the elevating column are arranged one after the other, making up four columns in appearance, but the lower crosshead is fixed to the fixed column and the upper crosshead is fixed to the elevating column. In such a configuration, when the hydraulic loading mechanism is actuated, the lifting table and the upper crosshead are raised and lowered, and a compression test is performed between the lifting table and the lower crosshead,
A tensile test is performed between both crossheads.

C1 Problem to be Solved by the Invention Even though the lifting table has a certain load area, the lower crosshead is supported only by two fixed columns, so the load axis is located on the line connecting the two fixed column axes. I'm going to do it. Therefore, the following problem arises. That is, for example, when a sample that is prone to buckling is subjected to a compression test, the buckling causes the load axis of the testing machine to deviate from the original load axis, resulting in an eccentric load being applied to the sample. Also, in bending tests, the load axis of the testing machine shifts due to the deformation of the sample. In this case, there are two fixed columns and the configuration is weak against lateral forces.
Unnecessary forces such as bending loads act on the fixed support, reducing test accuracy. #i#: The durability of the test machine is also reduced.

98 Means for Solving Problems Three or more fixed columns are installed perpendicularly to the base of the load main body, means for fixing the crosshead in a movable manner using these fixed columns, and a load mechanism installed on the base. It comprises:

Between the load mechanism installed on the 89 action base and the crosshead fixed to the fixed column, the load range is within a certain range connecting the axes of the three fixed columns, and there is no risk of the load axis being deviated. do not have.

F. Example The present invention will be explained below according to an embodiment shown in the drawings.

FIG. 1 is a front view showing the entire material testing machine including a load main body portion equipped with the present invention, and FIG. 2 is a view taken from the plane 1--2 in FIG. 1. Reference numeral 1 denotes a base installed on the floor, which is usually rectangular in shape, and has fixed columns 4 hanging from each of its four corners. Although only two are shown in FIG. 1 because it is a front view, it is clear from FIG. 2 that four are installed vertically. Reference numeral 2 denotes a movable platform mounted on a base, and a ram 17 that moves up and down by a hydraulic cylinder 16 installed on the base 1.
It is integrally constructed with the elevating table 3 that is integrated with the elevating table 3.

This elevating table 3 has fixed columns 4 on both sides.
In the open position, the movable struts 5 are hung vertically, and this state is also clear from FIG. 2, and as a result, a total of six struts are hung vertically from above. and four fixed columns 4
On the other hand, a ladder 6 is held in the lower cross so as to be movable up and down, and an upper cross head 7 is fixed to the upper end of the movable column 5. In Figure 1, it appears that the upper cross head 7 is fixed to the upper end of the fixed column 4, but this is a front view, and the upper end of the fixed column 4 is exactly at the position of the cross head 7. This is because there is. In addition, the second
As shown in the figure, the movable strut S passes through a large diameter hole drilled in the crosshead. The lower crosshead 6 is fixed to the identification column 4 by a so-called hugging restraint method. That is, as shown in FIG.
K, and by reducing the gap in this notch 6, it is restrained and fixed. Specifically, it is configured such that the distance between the extension parts 6F and 6F of the crosshead 6 can be reduced or opened by the hydraulic cylinder 8 and the connecting rod 9. When the distance between the extension parts 6F and 6F is reduced by the operation of the hydraulic cylinder 8, the crosshead 6 embraces and restrains each fixed column 4 at the notch 6K and is fixed to the fixed column 4. When the restraint is released, the lower cross member 6 can be moved up and down relative to the fixed support 4 and adjusted to a desired height position. This height position adjustment is performed by operating the hydraulic cylinder 14 and rod 15 that constitute the crosshead lifting device. When pressure oil is supplied to the hydraulic cylinder 14, the piston 15 expands and contracts, and the lower crosshead 6 moves up and down. The operation of raising and lowering the lower crosshead 6, restraining it to the fixed column 4, and releasing it are controlled and adjusted by the operating section S. When pressure oil is introduced into the hydraulic cylinder 16 with the lower crosshead 6 fixed, the sample (test piece, specimen,・・・
(not shown) compression tests were performed on both crossheads 6.7
In between, a tensile test is performed on a sample (not shown) held by both chucks. During the tensile test, the rad 7 moves to the position indicated by the two-dot chain line in the upper cross. The test results are displayed on the measuring section K. The hydraulic pressure source for each hydraulic cylinder may be one common source, or may be installed individually.

With the above configuration, the load range for the compression test is 4.
It becomes a rectangular area that connects each axis of the book fixing column 4, and the rigidity of the load body in the backward direction (vertical direction in Figure 2) becomes strong, even if the axis of the sample is eccentric from the load axis of the testing machine. The load axis is less prone to eccentricity. The characteristics of this invention are that the load range has a certain size and that it has a certain rigidity in the front, back, left and right directions, but there are several other embodiments that take advantage of this point. . For example, in the illustrated example, the identification column is 4.
Although it is made of wood, it is sufficient to have at least three of them; if there are more than three, a certain load range can be created by connecting the axes of each support. Although the illustrated crosshead has a rectangular shape with a long axis, it may also be square. Further, the fixed support may be a spring rod, and the lower crosshead may be screwed into the fixed support. In the case of this threaded rod type, the lower crosshead is raised and lowered by rotating the threaded rod or by rotating the screwed nut. From the perspective of reducing the weight of the entire main body, the illustrated example method is advantageous. In addition to compression tests, jigs for bending tests can also be used in standard (Q) formats.

G1 Effect of the Invention Since this invention is as explained above, the axial center of the sample can be tested even in compression tests or bending tests of materials that have a constant load range and are therefore prone to buckling. Even if the load axis is eccentric from the machine's load axis, the load axis will not be eccentric and the test can be performed with good accuracy. The rigidity of the load body also increases, and its mechanical strength also increases.

[Brief explanation of the drawing]

FIG. 1 is a front view of a material testing machine according to the present invention, and FIG. 2 is a plane view taken along line II-I in FIG. DESCRIPTION OF SYMBOLS 1... Kiwa, 2... Movable base, 3... Elevating table 4... Fixed support, 5... Movable support, 6... Lower cross head, 7... Upper cross head, 8 .14
．． 16...Hydraulic cylinder, 9...Connection rod, 10.1
1...Jig, 12.13...Chuck, 15...
・Piston, 6F...Crosshead extension, 6K...
・Notch portion patent applicant Shimadzu Corporation representative
Patent attorney Hiko Takeishi - Bar L. 7th Edition.

Claims (1)

[Claims] The cross head is equipped with three or more fixed columns vertically installed relative to the base of the load body, means for fixing the crosshead so that it can be raised and lowered by these fixed columns, and a load mechanism installed on the base. A material testing machine characterized by performing a compression test on a sample between a head and a load mechanism.