In a governor of the Hartnell type the arms of the bell-crank levers are equal in length, and those carrying the operating masses are vertical when the governor is rotating at its mean speed of 775 rev/min, with the masses moving in a circle of 175 mm diameter - The usual central controlling spring is replaced by two parallel tension springs direetly connecting the operating masses. Find (a) the magnitude of each operating mass if a force of 90 N is required at the sleeve to maintain it in the mean speed position when the specd is increased from 775 to 800 rev/m in (b) the stiffness, or rate, of each spring if the ratio of sleeve movement to increase of speed is 1 mm to 10 revImin when in the mean speed position.

In a governor of the Hartnell type the arms of the bell-crank levers are equal in length, and those carrying the operating masses are vertical when the governor is rotating at its mean speed of 775 rev/min, with the masses moving in a circle of 175 mm diameter - The usual central controlling spring is replaced by two parallel tension springs direetly connecting the operating masses. Find (a) the magnitude of each operating mass if a force of 90 N is required at the sleeve to maintain it in the mean speed position when the specd is increased from 775 to 800 rev/m in (b) the stiffness, or rate, of each spring if the ratio of sleeve movement to increase of speed is 1 mm to 10 revImin when in the mean speed position.

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.48P: Find the smallest distance d for which the hook will remain at rest when acted on by the force P....

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