Review Questions

REVIEW QUESTIONS

1. List out the advantages and disadvantages of gear drive over other drives.

2. How do you classify gears? Explain briefly various types of gears.

3. What do you mean by pitch point, circular pitch, module, addendum and pressure angle? Explain in detail.

4. Diagrammatically show the following with reference to a spur gear tooth: Face width, Pitch circle, Clearance, Tooth thickness, Addendum and Dedendum.

5. With the help of a neatly drawn sketch of a spur gear, explain elaborately the nomenclature of gears.

6. State and prove the fundamental law of gearing.

[A.U., May/June 2007]

[Hint: Refer Section 4.7]

7. Derive an expression for the velocity of sliding between a pair of involute teeth.

8. Show that the involute curves as the profiles of mating gears satisfy the law of gearing.

9. State the advantages of involute tooth profile as compared to cycloidal profile.

10. Derive the equation to determine the length of path of contact between two spur gears of different size.

11. Prove that the maximum lengths of arc of contact between a pair of gear tooth to avoid interference is (r + R) tan ϕ.

[Hint: Maximum length of path of contact, MN = (r + R) sin ϕ

Maximum length of arc of contact = = (r + R) tan ϕ]

12. What is meant by interference in gears? What are the measures to eliminate the same? 

13. Explain the term undercutting in gears.

14. Derive an expression for minimum number of teeth on the wheel in order to avoid interference.

15. Two unequal gears of involute profile are to give required gear ratio. Derive an expression for the minimum number of teeth required for the pinion in order to avoid interference.

16. What are non-standard gears? State their advantages.