A spring controlled governor of the Hartnell type has two rotating balls of mass 1.35 kg each. The ball arm is 75 mm and the sleeve arm is 62.5 mm. In the mid position of the sleeve, the sleeve arm is horizontal and the balls rotate in a circle of 100 mm radius. The total sleeve movement is 30 mm. Due to maladjustment of the spring, it is found that the equilibrium speed at the topmost position of the sleeve is 420 r.p.m. and that corresponding to the lowest position is 435 r.p.m. Determine : 1. stiffness and initial compression of the spring, and 2. the required initial compression of the spring to give an equilibrium speed at the topmost position which is 12 r.p.m. more than at the lowest position. Neglect the moment due to mass of the balls.

Question-AnswerCategory: Machine DesignA spring controlled governor of the Hartnell type has two rotating balls of mass 1.35 kg each. The ball arm is 75 mm and the sleeve arm is 62.5 mm. In the mid position of the sleeve, the sleeve arm is horizontal and the balls rotate in a circle of 100 mm radius. The total sleeve movement is 30 mm. Due to maladjustment of the spring, it is found that the equilibrium speed at the topmost position of the sleeve is 420 r.p.m. and that corresponding to the lowest position is 435 r.p.m. Determine : 1. stiffness and initial compression of the spring, and 2. the required initial compression of the spring to give an equilibrium speed at the topmost position which is 12 r.p.m. more than at the lowest position. Neglect the moment due to mass of the balls.