When the textbook calculates the diameter of the shaft, he tells me some of his forces, such as the circumference force of the gear on the shaft, etc.. But in reality, the known conditions are quite small: "now I have a question, how to transform, please help me?"Just know that A is a cylindrical, M, radius R, B as a shaft, and A together, C motor, and B through the chain connection, will now enable A to R RPM speed rotation, so how to determine the motor power, what is the minimum diameter of the B axis? What is the moment and torque that the B axis receives if it is specific? Other conditions to be determined, free to add
When determining the length of each shaft, it is necessary to make the structure compact and ensure the assembly or adjustment of the parts. The length of each section of the shaft is determined by the axial dimension of the mating parts of each part and the necessary clearance between the adjacent parts. In order to ensure the axial positioning reliable, and gear and couplings and other parts to match, part of the shaft length should generally be shorter than the length of the wheel hub 2 ~ 3mm
Standard shafts shall be used as far as possible in accordance with the requirements of the shaft. Installation of standard parts (such as rolling bearings, couplings, seals, etc.) of the shaft diameter should be taken as the corresponding standard value and the selected combinations of tolerances.In order to make the gears, bearings and other mating parts to be easy to assemble and disassemble, and to reduce the scuffing of the mating surface, smaller diameters should be used before mating the shafts. In order to make with the axis of the interference fit parts, easy assembly, match shaft pressing end should taper; or the size tolerance in two different parts of the same section of the shaft.
The required diameter of each shaft is related to the load on the shaft. Preliminary determination of the diameter of the shaft, usually do not know the action point of force, can not determine the size and distribution of the bending moment, and so is not a specific load according to the axial stress and cause to determine the diameter of the shaft. But the torque on the shaft is usually obtained before the structural design of the shaft. Therefore, the minimum diameter Dmin of the shaft can be estimated by the torque of the shaft, and then the diameter of each shaft should be determined from the Dmin at the location of the shaft according to the assembly plan and the positioning requirements of the shaft. In actual design, the diameter of the shaft can be determined by the experience of the designer, or by the analogy of the same kind of machinery.
