Manufacturing Metrology - Measurement of Gear Errors

this presentation gives overall view about the Types of Errors in Gear and The Way to Measure error in Gears

1. Measurement of Gear Errors -by Nimaleshwar DK (22P122) Manufacturing Metrology

2. Spur Gear Terminology

3. Gear Ma nufacturing Process Gear Hobbing Hobbing is a gear cutting process that involves using a hob to cut the material into the desired shape and size. It is a quick process suitable for efficient production rate and working with gear blanks made from processes such as die casting. Gear Shaping Shaping is an advanced manufacturing process suitable for making gears incompatible with hobbing. It involves using a cutter having a pinion, rack, or single point shape to cut the blank to the required shape

4. Gear Broaching Broaching involves using a multi-teeth tool with embedded cutters to cut a blank. It is the quickest gear machining process and is suitable for making incrementally deep and embedded cuts Gear Milling Milling is a gear machining method many automotive gear manufacturers use for making gear teeth due to its versatility. Moreover, it has become more accurate with CNC milling machines.

5. Powder Metallurgy Powder metallurgy, from its name, involves setting up powder and heating the setup. The setup must be compact to ensure the formed gear has better mechanical properties on cooling.

6. ERRORS IN SPUR GEARS 1 . Gear blank runout errors 2. Gear tooth profile errors 3. Gear tooth errors 4. Pitch errors 5. Runout errors 6. Lead errors 7. Assembly errors

7. Five Common Gear Failure Modes

8. Measurement with Gear Tooth Callipers

9. Base tangent method The reader may recall that an involute is the path traced by a point on a circle that is rolling on a straight line without slipping. We can easily see that if a straight generator ABC is being rolled along a base circle, then its ends trace involute profiles A2 AA1 and C2 CC1 , as shown in Fig. 8.16. Therefore, any measurement made by gauging the span of a number of teeth will be constant, that is, AC = A1 C2 = A2 C1 = A0 C0 , where A0 C0 is the arc length of the base circle between the origins of involutes.

10. Pitch-measuring Instruments

11. Profile Measurement Using Special Profile-measuring Instruments Gleason gear inspection machine, a product of Gleason Metrology Systems Corporation, USA, follows the fundamental design aspect of any testing machine with the capability to handle up to 350 mm dia gears

12. Measurement of backlash

13. FaroArmCoordinate Measuring Machine (CMM)

14. Gear Quality Parameters DIN 3692:1978-08

15. References [1] ENGINEERING METROLOGY AND MEASUREMENTS by ,N.V. RAGHAVENDRA, L. KRISHNAMURTHY. [2] GEAR METROLOGY LECTURE BY DR. KANAKUPPI SADASHIVA IITM [3] ENGINEERING METROLOGY BY IC GUPTA [4] https://www.china-me.com/news/article/five-common-gear-failure-modes-and-diagnostic-techniques [5] https://www.youtube.com/watch?v=BAdPbHy8GgA (FARO Arm CMM)