Technical Requirements And Functions Of Internal Grinding Spindle

1、Support shaft journal
The roundness tolerance of the two supporting journal A and B of the main shaft is 0.003mm, and the radial runout tolerance is 0.005mm. The contact rate of the 1∶12 taper of the supporting journal is ≥ 70%. The surface roughness Ra is 0.2mm; The bearing journal size accuracy is IT5. Because the spindle bearing journal is used to install the support bearing, is the assembly reference surface of the spindle component, so its manufacturing accuracy directly affects the rotary accuracy of the spindle component.
2、End cone hole
The tolerance of the inner cone hole (Moh No. 2) at the end of the main shaft to the support journal A and B is 0.005mm at the end of the shaft, and 0.01mm at the 300mm away from the end of the shaft; Taper contact rate ≥ 70%; The surface roughness Ra is 0.4mm; Hardness requirements 45~50HRC. The cone hole is used to install the tip or tool taper handle, its axis line must be strictly coaxial with the two supporting shaft journal axis line, otherwise it will cause the workpiece (or tool) coaxiality error.
3、End short cone and end face
The radial circular runout tolerance of the head short cone C and end face D to the two supporting journal A and B of the main shaft is 0.008mm; The surface roughness Ra is 0.8mm. It is the positioning surface of the mounting chuck. In order to ensure the centering accuracy of the chuck, the conical face must be coaxial with the supporting journal, and the end face must be perpendicular to the rotation center of the spindle.
4、Empty gear journal
The radial runout tolerance of the empty gear journal to the supporting journal A and B is 0.015mm. Because the journal is the surface that matches the gear hole, there should be a certain coaxiality requirement for the supporting journal, otherwise it will cause poor meshing of the spindle drive. When the spindle speed is very high, it will also affect the smoothness of the gear drive and produce noise.
5、thread thread
The error of the screw surface on the spindle is one of the reasons for the run-out of the end face of the pressing nut, so the machining accuracy of the thread should be controlled. When the end face runout of the pressing nut on the spindle is too large, it will make the axis line of the inner ring of the pressed rolling bearing tilt, thus causing the radial round runout of the spindle.