Figure shows a friction brake in which the curved lever BC is pivoted at the fixed-point and carries a friction lining which presses on the rotating drum D over an arc of 90°. The diameter of the drum is 250 mm. The distances OB and OC are each 150 mm. The pressure exerted by the friction lining on the drum at any point P is 350sine kN/m2. The lining is 50 mm wide and the coefficient of friction is 0.3. Calculate the braking torque exerted on the drum, also the amount of the force F which is required at B to apply the brake. The drum rotates in a clock-wise direction.

Figure shows a friction brake in which the curved lever BC is pivoted at the fixed-point and carries a friction lining which presses on the rotating drum D over an arc of 90°. The diameter of the drum is 250 mm. The distances OB and OC are each 150 mm. The pressure exerted by the friction lining on the drum at any point P is 350sine kN/m2. The lining is 50 mm wide and the coefficient of friction is 0.3. Calculate the braking torque exerted on the drum, also the amount of the force F which is required at B to apply the brake. The drum rotates in a clock-wise direction.

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 7.60P: The force P applied to the brake handle enables the band brake to reduce the angular speed of a...

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