Page 425 - Marks Calculation for Machine Design

P1: Naresh
January 4, 2005
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Brown.cls
Brown˙C09
U.S. Customary MACHINE ENERGY SI/Metric 407
Step 11. Compare the total weight of the com- Step 11. Compare the total weight of the com-
posite flywheel found in step 10 with the weight posite flywheel found in step 10 with the weight
of the solid disk flywheel found in step 1. of the solid disk flywheel found in step 1.
W solid disk 860 lb W solid disk 3,884 N
= = 1.87 = = 1.85
W 461 lb W 2,100 N
composite composite
flywheel flywheel
This example shows that a composite flywheel can be designed that has the same mass
moment of inertia as a solid disk flywheel; however, it only weighs a little over half as
much. Also, the width of the rim was the only dimension that was unknown, and it came
out to be only 50 percent wider than the thickness of the solid disk flywheel.
This concludes the discussion on the two most important design elements associated
with machine energy: helical springs and flywheels. The next chapter discusses machine
motion, which includes all the design information on the three most famous mechanisms:
slider-crank, four-bar, and quick-return mechanisms. Also included are discussions on both
spur and planetary gear systems, and the motion of pulleys and wheels.