JPS63133037A - Material tester with calibrator - Google Patents

Abstract

PURPOSE:To achieve a higher workability of calibration, by applying a calibration load arranged in an upper support body to a load cell with the lift of a crosshead. CONSTITUTION:A weight receiving means 13 is inserted through a through hole 12 provided in an upper support body 3 and a weight 11 of a specified load weight is placed thereon; they are covered with a cover 14. A crosshead 4 is lifted with no test piece 16 mounted thereon to make an upper end face 15a of a load cell connecting means 15 abut a lower end face 12a of the weight receiving means 13 and with the further lift thereof, the weight 11 of the specified load is held with a load cell 8 through the weight receiving member 13, where the weight 11 and the load of the weight receiving means 13 work on the load cell 8. But, as the load applied is known, under such a condition, the gain adjustment of an amplifier is performed within a load detection circuit to complete the calibration. After the end of the calibration, a test piece 16 is mounted between an upper grip 6 and a lower grip 7. Then, a test is conducted as in the past.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application This invention relates to a material testing machine equipped with a load cell calibration device for detecting test loads.

B. Prior Art In FIG. 4, which shows a schematic configuration of a conventional material testing machine, a pair of screw rods 2 are rotatably provided between a base 1 and an upper support 3 disposed above the base 1. When the screw rod 2 is rotated by the rotation of a drive motor (not shown) provided inside the base 1, the crosshead 4 is raised or lowered. A load cell 8 for detecting a test load is installed on the upper part of this cross ladder 4, and an upper grip 6 is suspended via a universal joint 5. A test piece is sandwiched between this upper grip 6 and a lower grip 7 (not shown) provided on the base 1, and the rod 4 is raised or lowered to the cross to apply tensile or compressive loads to the test piece. put on.

The load applied to the test piece is measured by load cell 8,
In order to accurately measure the load, it is necessary to periodically calibrate the load cell 8 using the actual load. Conventionally, the upper grip 6 grips a weight suspension 9 for calibration, the lower grip is removed as shown in the figure, and a weight 11 with a predetermined load is attached to the weight suspension 9 via a weight holder 10. The load cell is calibrated by hanging it.

Problem to be solved by the C0 invention When calibrating such a load cell 8, the upper grip 6
The work of grasping the weight lifting tool 9, the work of suspending the weight holder 10 and the weight 11, the work of removing the lower gripping tool,
After calibration, the weight hoist 9, weight holder 10, and weight i! 11
This requires a lot of time and effort to prepare for calibration and assemble after calibration. It was necessary to hang it from the weight hanging device 9, which caused problems such as high risk.

An object of the present invention is to provide a material testing machine with a calibration device that eliminates such conventional problems.

Means for solving problem D1: A through hole is drilled in the load axis direction in the upper support installed above the crosshead, and a calibration load is placed in the upper support. The calibration load is configured to be applied to the load cell via.

The E0 action crosshead is raised to apply a calibration load to the load cell through the through hole in the upper support plate.

F. Embodiment FIG. 1 is an overall schematic diagram showing an embodiment of a material testing machine with a calibration device according to the present invention, and FIGS. 2 and 3 are diagrams illustrating the operation of the above-mentioned testing machine during calibration. The same parts as in FIG. 4 will be described with the same reference numerals.

A through hole 12 is provided in the center of the upper support body 3, a weight holder 13 is inserted into the through hole 12 so as to be movable up and down, and a weight 11 with a predetermined load is placed on the weight holder 13. and cover them with a cover 14. In addition, as in the conventional case, an upper grip 6 is supported by a load cell 8 installed on a crosshead 4 via a universal joint 5, and a test piece 16 is placed between it and a lower grip 7 installed on a base 1. It will be installed.

Calibration of the load cell 8 is performed as follows.

With no test piece 16 attached, the crosshead 4 is moved to the second position.
As shown by arrow A in the figure, the upper end surface 15a of the load cell connector 15 is brought into contact with the lower end surface 12a of the weight holder 13, and the crosshead 4 is further raised as shown in FIG. A weight 11 with a predetermined load is held by a load cell 8 via a weight holder 13. Loads from the weight 11 and the weight holder 13 are applied to the load cell 8 . Since the load on the load cell 8 is known, the gain of the amplifier in the load detection circuit is adjusted in this state and the calibration is completed. If the total load of the weight 11 and the weight holder 13 is the rated maximum load of the load cell 8, the amplifier gain is adjusted to full scale. After the calibration is completed, the test piece 16 is attached between the upper grip 6 and the lower grip 7, and a test is performed in the same manner as in the conventional method.

The weight holder 13 may be omitted and a protrusion may be formed on the upper end surface of the load cell 8 in place of the weight holder. The vertical mechanism of the crosshead 4 does not need to be based on a screw rod.

G6 Effects of the Invention Since the present invention is configured as described above, each time a load cell is calibrated as in the conventional case, it is necessary to attach a heavy weight, a weight suspender for suspending the weight, and a weight holder. Ingredients,
Also, the work of attaching and detaching the lower grip is not required, and the work efficiency is improved. Further, since the operator does not have to manually lift and operate the heavy weight, the calibration work can be carried out safely.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a material testing machine with a calibration device showing an embodiment of the present invention, Figs. 2 and 3 are operation explanatory diagrams explaining the calibration of a load cell, and Fig. 4 is a conventional material testing machine. FIG. 1: Base 2: Screw rod 3: Upper support 4: Crosshead 8: Load cell 11 Double weight 12 2 through holes 13: Weight holder patent applicant
Shimadzu Corporation Patent Attorney Fuyuki Nagai Figure 1

Claims (1)

[Claims] In a testing machine that detects the applied load of a test piece with a load cell installed in a crosshead, a through hole is drilled in the load axis direction in an upper support constructed above the crosshead, and a through hole is drilled in the upper support. A material testing machine with a calibration device, characterized in that a calibration load is arranged and the calibration load is applied to a load cell through a through hole when a crosshead rises.