An elevator type lift is being designed to raise a load up to 5,000pounds between floors. Two square-thread lead screws, 1.5 inches in (major) diameter, are used for this application. Determine the torque required to raise this lift if the moving part of the elevator weighs 800 pounds and the coefficient of friction is assumed to be 0.15. For the elevator described, find the efficiency and power required if each lead screw is driven at 175 rpm. Verify if this is self locking.

An elevator type lift is being designed to raise a load up to 5,000pounds between floors. Two square-thread lead screws, 1.5 inches in (major) diameter, are used for this application. Determine the torque required to raise this lift if the moving part of the elevator weighs 800 pounds and the coefficient of friction is assumed to be 0.15. For the elevator described, find the efficiency and power required if each lead screw is driven at 175 rpm. Verify if this is self locking.

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 7.90RP: The screw of the clamp has a square thread of pitch 0.16 in. and a mean diameter of 0.6 in. The...

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