In case of new clutch,the intensity of pressure is uniform along the surface of clutch but in case of old clutch uniform theory is more correct. Single plate clutch uniform pressure theory assuming that the. The other theory assumes that the wear is uniform in which case the pressure is not evenly distributed. From the above comparison we find that uniform wear theory has low torque capacity than uniform pressure theory. Sep 06, 2017 in this channel all information related to mechanical field i. You can write the answer and upload relevant images to justify the answer if required lets together discuss and contribute in. A disc is bolted to flywheel which is known as pressure plate or driving disc. Theory of machines questions and answers single plate clutch. Design of plate clutch uniform pressure theory and. The normal force applied to a conventional disc type friction clutch will result in a given level of torque transfer until the clutch begins to slip. For designing friction clutch, which assumption would you.
The minimum braking torque is obtained for an initial speed of 88 kmh, in contrast to the previous case, and the maximum braking torque is obtained for an initial speed of 36 kmh. The following are considered during the design of the friction clutch. The simplest type of clutch is the singleplate clutch in which an annular plate with a surface of friction material is forced against a metal disk by means of a spring, or springs, or by other means. Brakes and clutches study notes for mechanical engineering. The total torque transmitted, for uniform pressure theory for uniform wear theorycone clutch. The maximum lining pressure will be 60 psi and the coefficient of friction f. The operating member consists of a pedal or lever which can be pressed to disengaged the driving and driven plate. What is clutch the clutch is a mechanical device used to connect or disconnect the driven shaft from the driving shaft at the will of the operator while power is transmitted from driving to drivenshaft. Pdf design and analysis of an automotive single plate clutch. Rim diameter is 560 mm and coefficient of friction is 0. Calculate the face width w of the cone, on the basis of the uniform pressure assumption.
To calculate the torque capacity of the clutch well have a look at the geometry of the clutch friction disc. Analysis of single plate clutch asbestos material input parameters youngs modulus164. One theory assumes the pressure is even over the surface of contact in which case the wear is greater at the outside due to the greater velocity of rubbing. What are uniform pressure and uniform wear theories. How to calculate the torque capacity of a clutch x. Assume, p is the pressure on friction surfaces at a distance r from the axis of the clutch. Assuming that the intensity of pressure over the entire contacting surface area is constant, total torque transmitted by single plate clutch can be obtain by integrating equation then, pconstant 2 2 2 1 r r. Analysing the stresses in thinwalled pressure vessels and stresses in thickwalled cylinders lo3 analyse the specifications of power transmission system elements specifications.
Multiplate clutch clutch applied and interdisciplinary. When the mating component in clutch, bearing are new, then the contact between surfaces may be good over the whole surface. Consider a car that uses a clutch with a mean radius of 12cm, and the width of the padding on the clutch is 3cm. Pressure plate of a single plate clutch was modeled and ansys software was used for structural and thermal. The torque transmitting capacity for one pair of the clutchs contacting surfaces under uniform pressure theory is t s ufr pf, where f is the actuating force. That means the force on the clutch padding will be about 833n. Uniform pressure theory assuming that the intensity of pressure over the entire contacting surfaces area is constant, then, p constant pressure is uniformly distributed over the contacting surfaces area, p total torque transmitted by cone clutch can be obtained by integrating the equation 1 within limits r2 to r1 we get, 2 2 2 1 rr w. If we use uniform wear and graph the two values of frictional torque vs axial load. As described in the case of a brake pedal travel of 40% see figure 5. A friction material clutch plate is sandwiched between the pressure plate and the flywheel face. It means that the pressure over the rubbing surfaces is uniform distributed. Brakes and clutches machine design applied mechanics. Brakes and clutches machine design applied mechanics and. Clutches theory of machines engineering reference with.
Sep 19, 2010 the theory of uniform effects is simply. This plate can slide freely to and fro on the clutch shaft. Classification of clutches, torque transmission capacity. Numerical problems on clutches the uniform wear theory assumes that the pressure intensity remains constant along the radial direction, this assumption holds good only when the clutch is in new condition. The maximum pressure which can be imposed on the friction material is 1. Which of the two assumptionsuniform intensity of pressure or uniform rate of wear, would you make use of in designing friction clutch and why. Ri96 mm, ro120mm, w1447 n problems on multiple plate clutch p r o b 5.
F a n the normal force pressing the clutch plate t c nm the torque capacity of the clutch r 1 m the inner radius of the friction surface r 2 m the outter radius of the friction surface. Which of the two assumptions uniform intensity of pressure or uniform rate of wear, would you make use of in designing friction clutch and why. The clutch pressure plate is a spring loaded device. A multiple disc clutch has five plates having four pairs of active friction surfaces. A multiple friction clutch is required to transmit 89. After one year, newcomb 2 investigated the torque capacity and the amount of heat dissipated of the dry clutch during a single engagement assuming a uniform wear of the clutch surfaces. Assuming uniform wear theory for the clutch plate, the maximum torque in n. This equation is used to obtain the actuating force required to operate a cone clutch or brake. Design of plate clutch uniform pressure theory and uniform. This means that everyone, no matter their differences in demographic, will react similarly and with the same amount of emotion as any other person in the populace.
This condition is not valid for old clutches, bearings because mating surfaces may have uneven friction. The total torque transmitted, for uniform pressure theory for uniform wear theorycone clutch design, advantages and disadvantages. Single plate clutch uniform pressure theory assuming that. The assumption is made that the contact pressure distribution is based on uniform wear theory. The uniform pressure theory i s applicable only when the friction lining is new. Optimization of brake actuation pressure versus braking torque pedal travel 40%. But when the wear occurs on the clutch lining the pressure doesnt remains uniform but it. Which of the two assumptionsuniform intensity of pressure or. High temperatures appear in the contacting surfaces of a singledisc clutch system friction clutch disc, flywheel and pressure plate due to the relative motion between these parts during the sliding period. Which of the two assumptionsuniform intensity of pressure. His approach showed largely agreement with the experimental results. Among uniform wear theory and uniform pressure theory, which.
Flat and vsection belt drive theory operation of friction clutches with uniform pressure and. The uniformpressure theory i s applicable only when the friction lining is new. The operating member consists of a pedal or lever which can be pressed. Tuhh open research tore thermal behavior of friction. Oct 25, 2015 uniform pressure theory assuming that the intensity of pressure over the entire contacting surfaces area is constant, then, p constant pressure is uniformly distributed over the contacting surfaces area, p total torque transmitted by cone clutch can be obtained by integrating the equation 1 within limits r2 to r1 we get, 2 2 2 1 rr w. Theory of machine classification of clutches, torque transmission capacity, considerations for uniform wear and uniform pressure theory 2. Among uniform wear theory and uniform pressure theory. When the clutch plate is new thick, the springs of the pressure plate are under greater tension than when the clutch plate has thinned down with wear. Analysis of single plate clutch 23 applying loads on single plate clutch applied pressures on single plate clutch analysis of single plate clutch. Namely, i the considered friction clutch has been treated as a friction connection of elastic bodies taking into account flexibility of the material of friction linings in axial direction.
So the intensity of the pressure applied on the clutch or bearing is assumed to be the same all over the surface that is known as the uniform pressure theory. Generally the motor shaft is pinned or keyed to the clutch rotorshaft assembly 1 bore input, with the load connected to the armature output of the clutch 2 by a pulley or gear. The plates are alternatively of steel and phosphor bronze and they run in oil. The pressure p pa acting on the clutch is equal with the ratio between the normal force f a and the area of the friction surface s m 2. Design of clutch the design of the clutch is based on two theory named as uniform pressure theory and uniform wear theory. Individuals whom live in a mass society all react and comprehend the media messages strongly and in the same way. There are two theories which give slightly different values of torque capacity. You can share the question you can get updates of new questions on facebook linkedin. The sensor technology existing in the system appropriate sensors coupled to a computer via a usb control and measurement module provides a convenient way to read and then to process and. Applying more normal force than that needed to prevent slipping will not improve the torque capacity of the friction clutch. Uniform pressure theory uniform wear theory bearing. Feb 24, 2019 theory of machine classification of clutches, torque transmission capacity, considerations for uniform wear and uniform pressure theory 2. Also determine the axial thrust to be provided by the springs. Which of the two assumptions 1 uniform intensity of pressure or 2 uniform rate of wear, would you make use of in designing friction clutch and why.
You can write the answer and upload relevant images to justify the answer if required lets together discuss and contribute in making the best answer. Thermal behavior of friction clutch disc based on uniform. These high temperatures are responsible for several disadvantages such as increasing wear rate, surface cracks and permanent distortions. Why in old clutches uniform wear theory is used instead of. The outer diameter of the clutch plate is 200 mm and its internal diameter is 100 mm. Design a cam for operating the exhaust valve of an oil engine. Friction clutches mechanical engineering mcq questions.
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