Fully-distributed tooth root bending stress dynamic detecting device and method

Abstract

The invention relates to a fully-distributed tooth root bending stress dynamic detecting device and method. The device includes a frequency sweeping laser, an optical splitter C1, optical splitter C2, a coupler C3, a coupler C4, a polarization maintaining coupler C5, a coupler C6, a polarization analyzer A1, a polarization analyzer A2, a photoelectric detector D1, a photoelectric detector D3, a photoelectric detector D4, an optical circulator, a fiber-optic rotary connector, a delayed optical fiber, a wavelength calibration tool, an isolator, a processor and a polarization-maintaining fiber grating which is attached on a gear tooth root in the axial direction of the gear tooth root. The device can dynamically detect the bending stress of each point at the gear tooth root in real time, the accuracy is high, the spatial resolution is high, the structure is simple, and the device and the method are not affected by external factors such as temperature and electromagnetism.

Description

technical field [0001] The invention relates to the technical field of optical fiber grating tooth root bending stress detection, in particular to a fully distributed dynamic detection device and method for tooth root bending stress. Background technique [0002] In the fields of automobiles, agricultural machinery, transmission, industry, etc., gears are widely used, and where there are transmissions, various gear combinations are inseparable. The dedendum bending fatigue failure is one of the important manifestations that affect the gear performance, so it is very meaningful to accurately and real-time detect the bending stress of the gear dedendum. Ultra-long polarization-maintaining fiber grating (length greater than 10cm) has many excellent characteristics such as flexibility and small insertion loss. There is a difference in thermal expansion coefficient between the stress-applied region and the cladding in the polarization-maintaining fiber grating structure, which ma...

AI Technical Summary

Problems solved by technology

For example, in the traditional resistance strain gauge testing technology, a metal strain gauge is affixed to the tooth root of the gear. Under the action of external pressure, the resistance of the strain gauge changes. The magnitude of the bending stress is obtained, but this method has some defects. For example, the strain gauge used is a metal material, which will be affected by many external factors, and it can only measure the average bending stress at the tooth root of the gear, and cannot be divided Point measurement; Another example is the measurement method of the stress and strain of the tooth root of the fixed central gear of the Chinese patent CN104101380A, which is to install a grating probe at the rounded corner of the tooth root of the central gear. There are multiple Bragg gratings on the probe, and each The drift of the center wavelength of the grating is used to calculate its stress. The main defect of this method is that the length of the ordinary grating itself is about 1cm, and the width of the gear is relatively limited, so only a few gratings can be installed on one tooth root. It can only measure the bending stress of a few points, which has limitations. In addition, this method can only measure the bending stress in the tooth width direction, and cannot realize the bending stress measurement in the tooth height direction of curved surfaces such as spiral bevel gears; and China Patent CN105404738A proposes a method for guiding gear stress detection and dedendum stress analysis. Through ANSYS, dynamic and static methods and 3D modeling software ProE are used to analyze the gear of the inner ring gear meshing with a single planetary gear, and extract the dedendum Stress and distribution and other information, but the process of this method is relatively complicated, it cannot realize real-time dynamic measurement, and finally obtains the maximum value of the root equivalent stress, so it is not suitable for detecting the bending stress of the tooth root in practical applications

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