Theory of Machines: Unit III: Friction in Machine Elements
Review and summary
Theory of Machines: Unit III: Friction in Machine Elements
A brake is a mechanical device by means of which motion of a body is retarded for slowing down or to bring it to rest, by applying artificial frictional resistance.
REVIEW AND SUMMARY • A brake is a mechanical device by means of which motion of a body is retarded for slowing down or to bring it to rest, by applying artificial frictional resistance. • The main types of mechanical brakes are: (i) block or shoe brakes, (ii) band brakes, (iii) band and block brakes, and (iv) internal expanding shoe brakes. • For single block or shoe brake: Braking torque, TB = μ RN • r Case I: When line of action of braking force passes through the fulcrum of lever Case II: When line of action of braking force passes through a distance 'c' above the fulcrum Case III: When line of action of braking force passes through a distance 'c' about the fulcrum • For pivoted block or shoe brake (2θ > 60°): • For double block or shoe brake: • For band brake system: • For applied on the lever in simple band brake is given by • Tension ratio in band and block brake is given by • Braking of a vehicle: Retardation (a) of the vehicle when vehicle moves up an incline is given by
Theory of Machines: Unit III: Friction in Machine Elements : Tag: : Theory of Machines: Unit III: Friction in Machine Elements - Review and summary
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Theory of Machines
ME3491 4th semester Mechanical Dept | 2021 Regulation | 4th Semester Mechanical Dept 2021 Regulation