DieselShip's Online Content Library

Q3. A cam operated valve moves vertically with simple harmonic motion. The camshaft speed is 740 rpm and the valve is opened and closed during 140° of cam rotation. The valve travel is 90 mm, its mass is 1.7 kg and the valve opens vertically downwards against a spring.

Calculate EACH of the following:

(a) The minimum spring constant required at full opening to ensure that the valve remains in contact with the cam profile. (10)

(b) The percentage difference in valve velocity between maximum and a 20 mm displacement from the mid-travel position. (6)