What are the characteristics of gear hobbing and gear shaping?
Gear hobbing features:
1. High productivity.
2. The tooth profile accuracy of hobbing is lower than that of gear shaping. The number of tangents forming the tooth profile envelope is only related to the number of hob flutes and the number of basic worm heads. It cannot be increased or decreased by changing the processing conditions.
3. To process worm gear, only hobbing can be used.
Gear Shaping Features:
1. When cutting gears with large modulus, the gear shaping speed is restricted by the inertia of the reciprocating motion of the gear shaping cutter spindle and the rigidity of the machine tool; the cutting process has the time loss of idle travel, so the productivity is not as high as gear hobbing. Gear shaping is more productive than gear hobbing only when machining gears with small modules, multiple teeth and narrow tooth widths.
2. The number of tangents forming the tooth envelope is determined by the size of the circular feed and can be selected. When gear shaping, the cutting of the gear shaping cutter along the tooth direction is continuous, and the tooth surface roughness is finer during gear shaping.
3. The tooth direction error during gear shaping is mainly determined by the parallelism error between the rotation axis of the main shaft of the gear shaping machine and the rotation axis of the table. Due to the high frequency of reciprocating motion of the gear shaping cutter during operation, the wear between the main shaft and the sleeve is large, so the tooth orientation error of the gear shaping is relatively large.
4. To process gears with shoulders and double or multiple gears with narrow empty tool grooves, only gear shaping can be used.
Gear shaving features:
1. The machining accuracy of tooth shaving is generally 6 to 7 grades, and the surface roughness Ra is 0.8 to 0.4 μm, which is used for the finishing of unquenched gears.
2. The productivity of tooth shaving processing is high. It generally only takes 2 to 4 minutes to process a medium-sized gear. Compared with gear grinding, the productivity can be increased by more than 10 times.
3. Since the tooth shaving process is free meshing, the machine tool does not generate a motion transmission chain, so the machine tool has a simple structure and is easy to adjust.
1. High productivity.
2. The tooth profile accuracy of hobbing is lower than that of gear shaping. The number of tangents forming the tooth profile envelope is only related to the number of hob flutes and the number of basic worm heads. It cannot be increased or decreased by changing the processing conditions.
3. To process worm gear, only hobbing can be used.
Gear Shaping Features:
1. When cutting gears with large modulus, the gear shaping speed is restricted by the inertia of the reciprocating motion of the gear shaping cutter spindle and the rigidity of the machine tool; the cutting process has the time loss of idle travel, so the productivity is not as high as gear hobbing. Gear shaping is more productive than gear hobbing only when machining gears with small modules, multiple teeth and narrow tooth widths.
2. The number of tangents forming the tooth envelope is determined by the size of the circular feed and can be selected. When gear shaping, the cutting of the gear shaping cutter along the tooth direction is continuous, and the tooth surface roughness is finer during gear shaping.
3. The tooth direction error during gear shaping is mainly determined by the parallelism error between the rotation axis of the main shaft of the gear shaping machine and the rotation axis of the table. Due to the high frequency of reciprocating motion of the gear shaping cutter during operation, the wear between the main shaft and the sleeve is large, so the tooth orientation error of the gear shaping is relatively large.
4. To process gears with shoulders and double or multiple gears with narrow empty tool grooves, only gear shaping can be used.
Gear shaving features:
1. The machining accuracy of tooth shaving is generally 6 to 7 grades, and the surface roughness Ra is 0.8 to 0.4 μm, which is used for the finishing of unquenched gears.
2. The productivity of tooth shaving processing is high. It generally only takes 2 to 4 minutes to process a medium-sized gear. Compared with gear grinding, the productivity can be increased by more than 10 times.
3. Since the tooth shaving process is free meshing, the machine tool does not generate a motion transmission chain, so the machine tool has a simple structure and is easy to adjust.
.jpg?imageView2/1/w/80/h/70)
.jpg?imageView2/1/w/80/h/70)
Leave a comment