Popis: |
Involute helical gears, with advantages of large carrying capacity, smooth transmission and long life, etc., are widely used in automotive, mining, helicopters and other high-speed and heavy-load transmission system. Poor working conditions lead to fatigue crack and other faults of gear key parts such as tooth root and tooth face. To identify the root causes of gear faults, strain monitoring methods are often used to monitor the stress changes of gear key parts so as to work out individualized improvement plants. Good test results can be obtained using real-time wireless data collection technology when the gear is in low-speed and light loading condition, and we can get important data such as speed, torque and dynamic strain on tooth root, etc. However, involute helical gears tend to work in high-speed and heavy harsh conditions, especially when the gear speed reaches a large value (eg. 10000r/min above), gear strain measurement device will suffer big centrifugal force and the impact of shear force which may results partial bonded adhesive failure (cracks, erosion, etc.) and even whole peeling of strain gages, thus inaccurate and even error results will be obtained. Transient finite element analysis method is used in this paper to study the relationship between rotation velocity and test accuracy of strain gauge as well as the process of the bonded adhesive failure, which may provide effective guidance for the fault diagnoses of gear meshing. |