Example 1 An external force of 10 N

Example 1: An external force of 10 N is acting horizontally on the rocker link, 30 mm from the point D. Find the amount of torque to be applied to the crank AB to keep the mechanism in static equilibrium. [ME 302 DYNAMICS OF MACHINERY, Prof. Dr. Sadettin KAPUCU] 1

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Graphical method: F 14 & F 34 are measured directly from the scaled force polygon. 10 N stands for 50 mm 4

Example: Find all the pin (joint) forces and the external torque (T 5) that must be applied to gear 5 of the mechanism by using the analytical method. Neglecting friction. 5

F 32 y F 32 x 1000 N 2 F 12 y F 43 y W 3 3 F 13 x F 43 x T 3 a O 3 F 13 y F 23 x F 23 y 6

W 4 4 F 14 x F 54 y T 4 a F 54 x O 4 F 14 y F 34 x F 45 x F 34 y W 5 5 F 15 x F 45 y T 5 a O 4 T 5 F 15 y 7

Example : Neglect the gravity force for the mechanism shown in the Figure. Links 2 and 3 are uniform. E and D points are the centroids of the triangles. All frictions are neglected. a) Find all the pin (joint) forces and the external torque that must be applied to link 2 of the mechanism by using the analytical method. b) Find the external torque that must be applied to link 2 of the mechanism by using the Virtual Work method. 8

5000 N ANSWER- a): E FCx C F T 4 a FCy D 4 FBx B FBy FAx A 3 FAy (F 3 a)x T 3 a G 3 (F 3 a)y B FBx FBy 9

FAy A T 2 (F 2 a)x G 2 2 FO 2 x O 2 FAx (F 2 a)y FO 2 y 10

0 0 0 11