Seizure Recovery System For Fuel System Distributor

1. Seizure Recovery System For Fuel System Distributor Final Report Presentation Sponsored by Cummins Engine Company Team #11 Michal Brown, Keron Miller, Sean Edwards, Ben Nuttall

2. Background Information: Cummins has a fuel system distributor in production that seizes during overheating or debris ingestion. The warranty cost associated with the repair of the part is significant. Down time due to part failure is too long.

3. Customer Needs: • Our objective is to design a mechanism that will enable the rotor to break away from the gear pump shaft when the rotor seizes and then re-engage at the same timing.

4. Specifications: • Target disengagement torque of 30 in-lbs • Drag torque while disengaged should be less than 5 in-lbs • Must have a torsional fatigue life of 10 million cycles • Must be able to disengage/re-engage for at least 100 seizures without loss of torque • Must be able to re-engage in the same angular position as disengagement • Shaft alignment must be maintained

5. Specifications: • Wear resistance must be as good or better than the current design • Must be backwards compatible with the existing system with the exception of the existing driveshaft. This implies that the new parts must occupy the same amount of volumetric space as the existing design • Parts must add less than $21 to the cost of the engine

6. Photos

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8. Customer Interim Solution Part modifications:

9. Work Breakdown StructureMain Headings 1.0 Identify Customer Needs 2.0 Concept development 3.0 Analysis and Calculations 4.0 Manufacturing Drawings 5.0 Create Prototype(s) 6.0 Reports, Presentations, Meetings

11. Changes to Schedule -Concept analysis is extended into next semester -Final concept selection is delayed -Start date of manufacturing drawings is delayed

12. Concept Analysis • Free body diagrams were created for each concept. • A summation of forces was conducted. • The spring constants required to keep the design in equilibrium below the disengagement torque level were determined. • A search for suitable springs was conducted.

13. Concept Analysis - Concept #1 Result: Spring constants of 16-250 N/mm were found

14. Concept Analysis - Concept #2 Suitable springs were found to accommodate the geometry and spring rates ranged from 26-300 N/mm .

15. Concept Analysis - Concept #3 Spring constants of 20-226 N/mm were found. Springs that might fit within the geometry of the design are difficult to find.

16. Concept Analysis - Concept #4 Springs can be obtained to fit within the geometry. Our analysis yielded a spring constant of 134 N/mm for an angle of 20 deg.

17. Concept Analysis - Summary

18. ProE Drawing - Concept #2

19. ProE Drawing - Concept #4

20. Comparison Criteria • Cost • Ease of fabrication, assembly, installation and repair • Fatigue life - wear (ball & groove, surfaces) • Drag torque • Repeatability (disengagement torque) • Alignment, negative torque

21. Spring Semester Milestones: • Upon confirmation from our project sponsor, we would like to accomplish the following tasks for next semester. • Add friction to force anaylsis. • Determine drag torque while disengaged. • Find fatigue life and wear of components. • Select suitable materials for prototype. • Create engineering drawings. • Build and test prototype.

22. Spring Semester Milestones: • Depending on the results of our future analysis, it may be necessary to modify the concepts or develop new ones.

23. We continue to update our webpage: www.eng.fsu.edu/~nuttall/cummins

24. Questions?