Machinery's Handbook, 31st Edition
Disc Spring Stacking
353
F
L 0
L 1,2
H
h
F
d
D
Fig. 3. Disc Springs in Series Stacking L 1,2 Indices Indicate Length of Spring Stack under Minimum and Maximum Load.
Parallel: Parallel stacking generates a force that is directly proportional to the number of springs arranged in parallel. Two springs in parallel will double the force, three springs in parallel will triple the force, and so on. However, it is a common practice to use two springs in parallel in order to keep the frictional forces between the springs as low as pos- sible. Otherwise, the actual spring force cannot be accurately determined due to deviation from its theoretical value. For n disc springs arranged in parallel as in Fig. 4, the following equations are applied: F F n S s total total # = =
L H t n 1 0 = + − = + + − = + ^ h ^ h h t tn t h tn
(2)
d
L 0
H
h
D
Fig. 4. Disc Springs in Parallel Stacking Parallel-Series: When both higher force and greater deflection are required, disc springs must be arranged in a combined parallel-series stacking as illustrated in Fig. 5.
F
L 0
L
1,2
H
h
F
d
D
Fig. 5. Disc Springs in Parallel-Series Stacking Normally, two springs in parallel are nested in series stacking. Two springs in parallel, called a pair, double the force, and the number of pairs, n p , determines the total deflection, S total .
Copyright 2020, Industrial Press, Inc.
ebooks.industrialpress.com
Made with FlippingBook - Share PDF online