Precision shaft is a key part used to support rotating parts and transmit motion and power in mechanical structures. Its design must take into account material properties, structural rationality and processing accuracy. Precision shafts usually have the following characteristics:
Dimensional accuracy: The dimensional accuracy requirements of precision shafts are relatively high, usually IT5~IT7 level, while the dimensional accuracy requirements of transmission shaft necks are relatively low, generally IT6~IT9 level.
Geometric shape accuracy: The geometric shape accuracy requirements of precision shafts are strict, mainly including the roundness and cylindricity of shaft necks, external cones, Morse taper holes, etc. The tolerance should be limited to the dimensional tolerance range.
Mutual position accuracy: The positional accuracy requirements of precision shafts are high, especially the coaxiality requirements of the shaft neck of the assembled transmission parts to the supporting shaft neck. The radial runout of high-precision shafts is 0.001~0.005mm.
Surface roughness: The surface roughness requirements of precision shafts are relatively high. The surface roughness of the shaft diameter that matches the transmission parts is Ra2.5~0.63μm, while the surface roughness of the supporting shaft diameter that matches the bearing is Ra0.63~0.16μm. Precision shafts are widely used in a wide range of fields, including micro motor parts, precision electronic parts, automotive parts, office automation parts, household appliances and power tools. Its processing technology is complex, including plastic processing, metal cutting, metal heat treatment, precision grinding, surface treatment and precision cleaning.