Page 437 - Analysis and Design of Machine Elements

Units
Steps Computation Results Springs 415
6. Calculate spring (1) Spring pitch p p = 4.0 mm
dimensions Select = 0.5 mm, therefore
0
p = d + = 3.5 + 0.5 = 4.0 mm
0
(2) Pitch angle
p 4 ∘
= arctan = arctan = 2.6 = 2.6 ∘
D × 28
(3) Free height H f
The length of spring arm H = 40 mm. mm
h
The free length is H = 40
h
H = n(d + )+ d =7.5×(3.5+0.5) mm
f
0
+3.5=33.5mm H = 33.5
f
(4) The length of spring wire L
L = Dn + L = ×28×7.5+40 ×2
h L = 739.4 mm
= 739.4mm
7. Produce Omitted
drawings
References

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