The main movement of gear shaping refers to

Machining of gear shaper: downward movement is the main movement and cutting movement in up-and-down reciprocating movement.

A machining method for machining the tooth surfaces of internal and external gears or racks on a gear shaper with a gear shaper cutter. The machining process of gear shaper is equivalent to the meshing of a pair of spur gears in principle.

It is equivalent to a pair of cylindrical gears meshing, and the gear shaper cutter is equivalent to a modified gear. When gear shaping, the gear shaper cutter moves up and down to cut down; When the cutter moves and the gear shaper cutter is upward, the workpiece or cutter retreats a certain distance in the radial direction to prevent the cutter from scratching the machined surface; There are generating motion and radial feed motion.

Extended data:

In the machining process, the cutter cuts only a small part of the tooth slot of the workpiece every reciprocating motion, and the tooth surface curve of the tooth slot of the workpiece consists of the envelope of the cutting edge of the gear shaper cutter.

When hobbing, if machining with a single-head hob, generally only a little more than a week of cutter teeth participate in cutting, while when slotting, all cutter teeth participate in cutting, so the cumulative error of gear slotting cutter pitch will directly affect the cumulative error of workpiece pitch. If you want to shave the workpiece in the future, hobbing should be used before shaving, because it is free to roll when shaving, and it is difficult to correct the accumulated error of tooth pitch, but it can improve the tooth profile accuracy.

When hobbing, the number of cutter grooves is limited, and the edges and corners of tooth polygon are large. When slotting, with the decrease of the circumferential feed speed of the workpiece, the number of reciprocating movements of the gear shaper cutter can be relatively increased, thus reducing the polygonal edges and corners and reducing the surface roughness Rz value. In fact, the speed of the up-and-down reciprocating motion of the gear shaper cutter is constant, but the speed of the motion has changed.

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