Continuous method for manufacturing face gears
View Patent ↗A continuous method of manufacturing a face gear utilizing a tool, representing a plane which can be oriented to a face gear workpiece under an angle equal to the pressure angle of the mating pinion member of the gear set (e.g. the face gear set), and, which can be rotated around a virtual pinion axis to generate a tooth flank on the workpiece. The tool is a face cutter which performs a continuous indexing motion with equal hand of rotation of cutter and workpiece (e.g. face gear) thereby describing a hypocycloid path of motion and an indexing ratio of two cutter rotations during one workpiece gear rotation which will produce straight lines along the face width of the face gear.
1. A continuous indexing method of manufacturing a face gear having a predetermined number of teeth, said face gear having a plurality of tooth slots with each tooth slot comprising opposing first and second tooth flank surfaces, said method comprising:
providing a face gear workpiece having an axis of rotation;
providing a cutting tool having an axis of rotation and comprising a disk body with one or more cutting edges defining one or more cutting blade starts located on a face of said disk;
rotating said cutting tool and said workpiece at a ratio of two rotations of said cutting tool per one rotation of said workpiece;
engaging said cutting tool and said workpiece;
generating said tooth surfaces on said workpiece by moving the tool and workpiece relative to each other;
wherein said generating comprises additionally rotating said cutting tool about an axis of rotation of a virtual pinion in mesh with said face gear workpiece, said cutting tool describing a generating roll wherein the cutting edges emulate the rolling motion of a tooth of said virtual pinion rotating in mesh with said face gear workpiece during said generating.
2. The method of claim 1 wherein said workpiece comprises an even number of teeth with said number of teeth being twice the number of said starts of the cutting tool.
3. The method of claim 1 wherein said workpiece and said cutting tool rotate in the same direction about their respective axes of rotation.
4. The method of claim 1 wherein said cutting tool is tilted with respect to said workpiece.
5. The method of claim 1 wherein said cutting edges comprise inside and outside cutting edges.
6. The method of claim 1 wherein said first and second tooth flank surfaces are straight in the direction of the face width of said workpiece.
7. The method of claim 1 wherein the tooth surfaces of the workpiece are oriented at a pressure angle and the cutting edges of the tool are oriented at a pressure angle equal to the pressure angle of said workpiece.
8. The method of claim 1 where the cutting edges are involute shaped.
9. The method of claim 1 wherein the generating roll is a non-constant generating rolling relationship.
10. The method of claim 1 wherein said face gear comprises a pitch angle of 90 degrees.
11. The method of claim 1 wherein said face gear comprises a pitch angle of less than 90 degrees.
12. The method of claim 1 wherein said face gear comprises an internal face gear.