1 / 24

Gears

Gears. Inter American University of Puerto Rico Mechanism Design MECN 4110. Chapter 9. Mechanical Transmissions. Belts. Chains. Gears. Types of Gears. Spur Gears. Pinion. Gear. Spur Gears - Types. External Set: Opposite Movement. Internal Set: Movement in the same direction.

jayme-branch
Download Presentation

Gears

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Gears Inter American University of Puerto Rico Mechanism Design MECN 4110 Chapter 9

  2. Mechanical Transmissions Belts Chains Gears

  3. Types of Gears

  4. Spur Gears Pinion Gear

  5. Spur Gears - Types External Set: Opposite Movement Internal Set: Movement in the same direction

  6. Pinion and Gear

  7. The Fundamental Law of Gearing • The angular velocity ratio between the gears of a gearset remains constant throughout the mesh. • The angular velocity ratio (mV) is equal to the ratio of the radius of the input gear to that of the output gear • The torque ratio (mT)

  8. The cycloid and the involute: curve characteristics The involute is a curve which can be generated by unwrapping a taut string from a cylinder (called the evolute). Features of this involute curve: The Involute Tooth Form

  9. The Involute Tooth Form • The string is always tangent to the cylinder. • The center of the curvature of the involute is always at the point of tangency of the string with the cylinder. • A tangent to the involute is then always normal to the string, the length os which is the instantaneous radius of curvature of the involute curve.

  10. 14.5o, 20o and 25o

  11. Gear Tooth Nomenclature

  12. Gear Tooth Nomenclature

  13. Gear Tooth Nomenclature

  14. Gear Tooth Nomenclature

  15. Gear Tooth Nomenclature

  16. Gear Tooth Nomenclature

  17. Contact Ratio If mp is 1, then one tooth is leaving contact just as the next is beginning contact. Spur gears [1-2]. The minimum contact ratio for a smooth operation is 1.2. A minimum contact ratio of 1.4 is preferred and larger is better. Most spur gearsets will have contact ratios between 1.4 to 2.

More Related