The main cause of tooth tooth error is that the vertical feed direction of the hob is too skewed with the axis of the inner hole of the tooth blank. When machining helical gears, there is also an inaccurate additional motion. (1) Regarding machine tools and fixtures: Column triangular guides and table axis are not equal

Main cause of tooth error error

The vertical feed direction of the hob is too skewed toward the axial direction of the inner hole of the tooth blank. When machining helical gears, there is also an inaccurate additional motion.

(1) Regarding machine tools and fixtures:

Column triangular guides and table axis are not equal

Workbench end face is big

Top and bottom top different axes

The meshing clearance of the indexing worm gear pair is large

There is periodic error in the transmission of the indexing worm gear pair

Vertical feed screw pitch error

Large gear, differential exchange gear error

(2) Relevant work:

The end faces of the tooth blank are not parallel

The workpiece positioning hole is not perpendicular to the end surface

Solution

Focus on controlling the machine geometry and the correct installation of the workpiece.

(1) Regarding machine tools and fixtures:

Repair column accuracy and control machine thermal deformation

Repair the rotation accuracy of the workbench

Repair the accuracy of the rear column or the upper and lower thimbles

Reasonable adjustment of the meshing clearance of the indexing worm gear pair

Repair the accuracy of the parts of the indexing worm gear pair

If the vertical feed screw is not accurate due to wear and tear, it should be replaced in time.

The calculation error of the differential exchange gear should be controlled

(2) related to the workpiece

Control the parallelism error of both ends of the tooth blank

Control the perpendicularity of the positioning hole and the end face of the blank