6. Advantages and Disadvantages of Belt Drives
Advantages: (1) Suitable for transmission with large center distance. (2) The belt has good flexibility, which can alleviate impact and absorb vibration. (3) Slippage occurs between the belt and the pulley during overload, which can prevent damage to other parts. (4) Simple structure and low cost.
Disadvantages: (1) The outer size of the transmission is large. (2) A tensioning device is required. (3) Due to the sliding of the belt, a fixed transmission ratio cannot be guaranteed. (4) The belt life is short. (5) The transmission efficiency is low.
7. Definition of elastic sliding and slipping
Elastic sliding refers to sliding due to elastic deformation of materials. Slip refers to general sliding caused by overload. Elastic sliding is caused by the difference in tension. As long as the circular force is transmitted and tight edges and loose edges appear, elastic sliding will definitely occur. Therefore, elastic sliding is inevitable, and V2 is always greater than V1.
8. Advantages and disadvantages of chain drive compared to belt drive and gear drive
Compared with the belt drive, the chain drive has no elastic sliding and slippage, can maintain an accurate average transmission ratio, requires less tension, and the pressure acting on the shaft is also small, which can reduce the friction loss of the bearing, has a compact structure, and can Work in harsh environmental conditions such as high temperature and oil pollution.
Compared with gear transmission, chain transmission requires lower manufacturing and installation accuracy, and its transmission structure is simple when the center distance is large. Disadvantages of chain transmission - the instantaneous chain speed and instantaneous transmission ratio are not constant, the transmission stability is poor, and there is a certain impact and noise during operation.
9. The function of the shaft, the difference between the rotating shaft, the transmission shaft and the spindle
A shaft is a mechanical part used to support rotation. The rotating shaft not only transmits torque but also bears bending moment. The drive shaft only transmits torque and does not bear bending moment or the bending moment is very small. The spindle only bears bending moment and does not transmit torque.
10. Main requirements for shaft structural design
(1) The shaft should be easy to process, and the parts on the shaft should be easy to assemble and disassemble. (2) The shaft and parts on the shaft must have accurate processing positions. (3) Each part must be firmly and reliably fixed relative to each other. (4) Improve stress conditions and reduce stress concentration.