Service Tel:0510-85251139
0510-85310583
Service Tel:0510-85251139
0510-85310583
Precision Machine Tools Machine Tool gear design parameters selection:
1. profile angle α (pressure angle of the pitch circle) selection of standard gear tooth angle of 20 °. In order to improve the strength, sometimes with large profile angle (such as 23 °, 25 °, 28 °, etc.), so that the tooth profile and tooth thickness of the radius of curvature at the node tooth is increased to improve the carrying capacity, but will increase the load on the bearing. Using small pressure angle (less than 20 °), the minimum can avoid an increase in the number of teeth undercutting, increased overlap, thereby reducing noise and dynamic load, but will reduce the strength of the tooth. According to experience, if no special requirements, the proposed standard 20 ° pressure angle.
2. The lower modulus m satisfy the selection condition tooth bending strength, use a smaller modulus can be increased contact ratio gear pair, to reduce the slip ratio, the amount of gear cutting can be reduced, reducing manufacturing costs. But the attendant problems due to manufacturing quality and the installation will increase the risk of broken teeth, the actual use often use a larger modulus. Select modulus shall comply with GB / T1357 or according to empirical data, taking m = (0.015 ~ 0.02) a. The basic gear tooth profile should be consistent with the provisions of GB / T1356's. It is the center of a gear transmission distance.
3. Restricted gear teeth z undercut, have the least number of teeth of the pinion gear requirements. For the size of certain gears, increasing the number of teeth and modulus decreases significantly improve the transmission quality, it satisfies the following conditions in tooth bending strength, we should try to use more number of teeth.
4. helix angle ββ angle is too small, you will lose the advantages of helical gears; whichever is greater, the degree of overlap can be increased, so that the drive to improve stability, but it will cause a lot of axial force, and generally β = 8 ° ~ 15 °. Herringbone gear advisable larger, for example, take β = 25 ° ~ 40 °. For ordinary cylindrical gear, low-level low speed torque, can spur gear; the middle class usually take β = 8 ° ~ 12 °; high-speed level to reduce noise, it is preferable larger β angle, such as 10 ° ~ 15 ° .
