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Fundamentals of Stress and Vibration 1. Mathematics for Structural mechanics
[A Practical guide for aspiring Designers / Analysts]
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[Fig 1.81: material lost by the gear tooth]

Material lost = Drop in over pin dimension ∗ cos 90 − Φ = [0.25 ∗ cos(90 − 20)] = 0.085mm

Observe that, as the pressure angle Φ increases, the material loss also increases.

Example 5: find the maximum weight the mechanism could lift in the orientations shown in
[Fig 1.82], so that the cart of weight (W ) is not toppled. The orientation of the lifting mechanism
1
of weight (W ) is as follows:
2
Ø The cart is aligned parallel to the ‘x-axis’.
Ø The lifting mechanism makes an angle (θ) with the ‘x-axis’.
Ø The boom is in the plane of the lifting mechanism and makes an angle (Φ) with the
horizontal.
Ø The mechanism is firmly fixed to the cart.

QP No. SSC/Q4401, Version 1.0, NSQF Level 7, Compliant with Aero and Auto Industries, Page 83