8/2/2019 MAE 3191 Gears

1/26

MAE 3191 Spring 2012 Class 19 April 4, 201

MAE 3191

Gears (Ch. 15 in Juvinall)April 4, 2012

8/2/2019 MAE 3191 Gears

2/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Housekeeping

Midterm Corrections due Today HW #7 Due Monday 4/9 Progress Report 2 Due 4/18 HW #8 Due 4/18 HW #9 Extra Credit (possible 30 points

to HW) ProE Session Next Wednesday

8/2/2019 MAE 3191 Gears

3/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Projects

Machine shop vehicle work... Bulk of parts machined: this week & next Get gear train working: week of 4/16 4/20 Get timing mechanism working: week of 4/23

4/27 Testing and final assembly: 4/30 5/4

Competition Day Wednesday 5/9? Fabrication Demo 4/23

Demonstrate gear train functionality

8/2/2019 MAE 3191 Gears

4/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Checklist Support all shafts in two places (except motor

shaft). Check the motor polarity

Electrical connections should be clean and easilyaccessible Placement between the gears needs to be precise

for proper mesh Methods to attach gears, pulleys, etc to shafts:

pins, set screws, keys, press fit. Ensure vehicle length and timing mechanism will

allow the ENTIRE vehicle to fit in the parking zone. Placement of the RCA plug (requires 0.25"diameter

8/2/2019 MAE 3191 Gears

5/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Gears

8/2/2019 MAE 3191 Gears

6/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Conjugate Gear Tooth Action

8/2/2019 MAE 3191 Gears

7/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Involute Profile

8/2/2019 MAE 3191 Gears

8/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Conjugate Involute Profiles

8/2/2019 MAE 3191 Gears

9/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Gear Teeth Nomenclature

8/2/2019 MAE 3191 Gears

10/26

MAE 3191 Spring 2012 Class 19 April 4, 201

More Gear Teeth Nomenclature

8/2/2019 MAE 3191 Gears

11/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Difference in Diametral Pitch

8/2/2019 MAE 3191 Gears

12/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Rack and Pinion Basically just a gear with infinite

diameter

8/2/2019 MAE 3191 Gears

13/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Internal Gear (Planetary Gear Train)

8/2/2019 MAE 3191 Gears

14/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Manufacturing Gears

http://science.discovery.com/videos/how-its-made-gears.html

8/2/2019 MAE 3191 Gears

15/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Example

8/2/2019 MAE 3191 Gears

16/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Force Analysis

8/2/2019 MAE 3191 Gears

17/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Failure of Gear Teeth

8/2/2019 MAE 3191 Gears

18/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Alternating Loading

Alternating Loading with

8/2/2019 MAE 3191 Gears

19/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Alternating Loading withrespect to Constant Life Fatigue

Diagram

8/2/2019 MAE 3191 Gears

20/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Geometry Factor

8/2/2019 MAE 3191 Gears

21/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Geometry Factor for 25deg

8/2/2019 MAE 3191 Gears

22/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Velocity or Dynamic Factor

8/2/2019 MAE 3191 Gears

23/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Overload Factor

8/2/2019 MAE 3191 Gears

24/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Mounting Factor

8/2/2019 MAE 3191 Gears

25/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Reliability Factor

8/2/2019 MAE 3191 Gears

26/26

MAE 3191 Spring 2012 Class 19 April 4, 201

Example