Torque measurement apparatus and method for miniature tension-torsion fatigue testing machine

Abstract

The invention relates to a torque measurement apparatus and method for a miniature tension-torsion fatigue testing machine. One end of a torque sensor is connected with a bearing main shaft of an air thrust bearing coaxially by an elastic coupling and the other end is connected with a motor coaxially by an elastic coupling. The side of the torque sensor is fixed on a torque sensor fixation plate. The periphery of the air thrust bearing is fixed at a single-side flange bush type bearing fixation element; the bearing fixation element is fastened on a bearing fixation plate by a bolt; and the motor is fixed on a motor fixation plate by a bolt. The high-precision torque sensor measures a torque applied on a test sample by the motor; the air thrust bearing transmits the torque between the torque sensor and a rigid clamp and transmits a test axial load to a test machine rack by the bearing fixation element, thereby preventing the torque sensor from being damaged during axial overloading. According to the torque measurement apparatus and method, accuracy of the 1mNm-level torque measurement result can be guaranteed; and the blank of the micro-Nm-level torque measurement apparatus and method in the miniature tension-torsion fatigue testing system can be filled.

Description

technical field [0001] The present invention relates to a device and method for testing the mechanical properties of materials, in particular to a torque measuring device and method for a miniature tension-torsion fatigue testing machine, in particular to a torque measuring device using air bearings in the torsional action control unit of a miniature fatigue testing machine and methods. Background technique [0002] The miniature tension-torsion fatigue testing machine is a device mainly used to test the fatigue performance of materials under small tension, torsion or alternating tension and torsion loads. With the continuous deepening of the research on the multiaxial fatigue performance and scale effect of materials, the measurement accuracy of test load or torque sensors is getting higher and higher, and the tensile and torsional action ranges in micron-sized material tests may be less than 10N and 1mNm. The high-precision sensors used in the testing machine usually have...

AI Technical Summary

Problems solved by technology

The miniature tensile and torsion fatigue testing machine suitable for micron-scale material testing requires the measurement accuracy of the torque sensor to reach the microNm level, so that the limit of the high-precision torque sensor for the axial load is usually close to or lower than that of the tensile torsion multiaxial test Tensile direction test load, which exposes the torque sensor to the danger of overloading

On the other hand, in order to ensure the measurement accuracy of the test system, the torque caused by friction and eccentric connection during the torque transmission process at the lower end of the torque measurement shaft should be within the allowable error range of the test, and conventional methods such as using thrust bearings to avoid axial load overload It leads to friction torque of the same magnitude as the test torque, which cannot meet the measurement error requirements

The above two reasons make it difficult to apply high-precision torque sensors to the micro-Nm-level test torque measurement in the miniature tension-torsion multi-axis fatigue test system

At present, the torque test range of multi-axial tensile testing machines is mostly at the Nm level, and there is no miniature tensile and torsion fatigue testing machine with the ability to measure and control torque at the microNm level.

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