Uniform pressure theory clutch

Friction clutches mechanical engineering mcq questions. Nov 08, 2014 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. Clutches theory of machines engineering reference with. For designing friction clutch, which assumption would you. Optimization of brake actuation pressure versus braking torque pedal travel 40%. 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. 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. Analysis of single plate clutch asbestos material input parameters youngs modulus164.

You can write the answer and upload relevant images to justify the answer if required lets together discuss and contribute in. The coefficient of friction of contact surface should be high enough to hold the load with a minimum amount of axial force. Design of plate clutch uniform pressure theory and. Which of the two assumptionsuniform intensity of pressure or. 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. Feb 24, 2019 theory of machine classification of clutches, torque transmission capacity, considerations for uniform wear and uniform pressure theory 2. Ri96 mm, ro120mm, w1447 n problems on multiple plate clutch p r o b 5. When the mating component in clutch, bearing are new, then the contact between surfaces may be good over the whole surface. Design of plate clutch uniform pressure theory and uniform. 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. Pressure plate of a single plate clutch was modeled and ansys software was used for structural and thermal.

Consider a car that uses a clutch with a mean radius of 12cm, and the width of the padding on the clutch is 3cm. Among uniform wear theory and uniform pressure theory, which. Assume, p is the pressure on friction surfaces at a distance r from the axis of the clutch. Calculate the face width w of the cone, on the basis of the uniform pressure assumption. Thermal behavior of friction clutch disc based on uniform. Theory of machines questions and answers single plate clutch. 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. 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. The plates are alternatively of steel and phosphor bronze and they run in oil. 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 maximum pressure which can be imposed on the friction material is 1. Analysing the stresses in thinwalled pressure vessels and stresses in thickwalled cylinders lo3 analyse the specifications of power transmission system elements specifications.

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. The outer diameter of the clutch plate is 200 mm and its internal diameter is 100 mm. Classification of clutches, torque transmission capacity. It means that the pressure over the rubbing surfaces is uniform distributed. The operating member consists of a pedal or lever which can be pressed. Within the area of the friction surface we are going to represent an elementary area dx, at the distance x from the center. To calculate the torque capacity of the clutch well have a look at the geometry of the clutch friction disc.

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. Why in old clutches uniform wear theory is used instead of. The uniformpressure theory i s applicable only when the friction lining is new. 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.

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 machine design applied mechanics and. Pdf design and analysis of an automotive single plate clutch. Thermal behavior of friction clutch disc based on uniform pressure and uniform wear assumptions. 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. Which of the two assumptionsuniform intensity of pressure. 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. Single plate clutch uniform pressure theory assuming that the. A multiple disc clutch has five plates having four pairs of active friction surfaces. Brakes and clutches study notes for mechanical engineering. Theory of machine classification of clutches, torque transmission capacity, considerations for uniform wear and uniform pressure theory 2. If we use uniform wear and graph the two values of frictional torque vs axial load. Sep 19, 2010 the theory of uniform effects is simply.

The maximum lining pressure will be 60 psi and the coefficient of friction f. Rim diameter is 560 mm and coefficient of friction is 0. That means the force on the clutch padding will be about 833n. You can share the question you can get updates of new questions on facebook linkedin.

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. 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. The clutch pressure plate is a spring loaded device. What amount of power is to be transmitted by the clutch, for a given power, the torque is to be calculated by the power torque relation. 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. Also determine the axial thrust to be provided by the springs.

This plate can slide freely to and fro on the clutch shaft. Describe with the help of a neat sketch the design procedure of an internal expanding shoe brake. The total torque transmitted, for uniform pressure theory for uniform wear theorycone clutch design, advantages and disadvantages. His approach showed largely agreement with the experimental results. A multiple friction clutch is required to transmit 89. 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. The operating member consists of a pedal or lever which can be pressed to disengaged the driving and driven plate. This condition is not valid for old clutches, bearings because mating surfaces may have uneven friction.

The other theory assumes that the wear is uniform in which case the pressure is not evenly distributed. Brakes and clutches machine design applied mechanics. Therefore in case of friction clutches, uniform wear should be considered, unless otherwise stated. To carry out experimental studies of wear processes occurring in the friction clutch the mechatronic system with friction clutch shown in figure 2 was used. 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.

The following are considered during the design of the friction clutch. Design a cam for operating the exhaust valve of an oil engine. Sep 06, 2017 in this channel all information related to mechanical field i. This equation is used to obtain the actuating force required to operate a cone clutch or brake. What are uniform pressure and uniform wear theories. A friction material clutch plate is sandwiched between the pressure plate and the flywheel face.

Flat and vsection belt drive theory operation of friction clutches with uniform pressure and. 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. Which of the two assumptionsuniform intensity of pressure or uniform rate of wear, would you make use of in designing friction clutch and why. Uniform pressure theory uniform wear theory bearing. Analysis of single plate clutch 23 applying loads on single plate clutch applied pressures on single plate clutch analysis of single plate clutch. Design of clutch the design of the clutch is based on two theory named as uniform pressure theory and uniform wear theory.

Among uniform wear theory and uniform pressure theory. 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. There are two theories which give slightly different values of torque capacity. Electromagnetic clutch an electromagnetic clutch in its simplest form is a device used to connect a motor to a load. How to calculate the torque capacity of a clutch x. 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. A disc is bolted to flywheel which is known as pressure plate or driving disc. But when the wear occurs on the clutch lining the pressure doesnt remains uniform but it. The assumption is made that the contact pressure distribution is based on uniform wear theory. The total torque transmitted, for uniform pressure theory for uniform wear theorycone clutch. The uniform pressure theory i s applicable only when the friction lining is new. Applying more normal force than that needed to prevent slipping will not improve the torque capacity of the friction clutch. Assuming uniform wear theory for the clutch plate, the maximum torque in n.

From the above comparison we find that uniform wear theory has low torque capacity than uniform pressure theory. These high temperatures are responsible for several disadvantages such as increasing wear rate, surface cracks and permanent distortions. Single plate clutch uniform pressure theory assuming that. According uniform wear theory, pr constant total frictional torque acting on clutch. Individuals whom live in a mass society all react and comprehend the media messages strongly and in the same way. 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. 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. 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. Following things has to be considered while designing. As described in the case of a brake pedal travel of 40% see figure 5.