Dme 5201 tom lecture 9 12 clutches
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This document provides an overview of clutches and their operation. It discusses the basic components and functions of clutches, including engaging and disengaging the transmission from the engine. It then describes different types of clutches in more detail, including single plate clutches, multi-plate clutches, and cone clutches. The key principles of how these clutches work to connect or disconnect power transmission are explained.
Dme 5201 tom lecture 9 12 clutches
- 1. THEORY OF MACHINES (DME 5201) UNIVERSITY POLYTECHNIC GLA UNIVERSITY, MATHURA LECTURE 9-12
- 2. MODULE -1_Lecture 9-12: Contents UNIVERSITY POLYTECHNIC GLA UNIVERSITY, MATHIURA 2 • Introduction to clutches and its working principle • Single plate Clutch • Multi-plate clutch • Cone clutches
- 3. Introduction to clutches • The transmission system takes power from engine-crankshaft and transmits it to the wheels. While transmiting this power, it is required to continue or discontinue the power transmission process by engaging and disengaging the transmission system to engine crankshaft. This enganement and disengagement is performed by clutch. • In short, the motion of the crankshaft is transmitted to the gearbox through the clutch. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 3
- 4. • A Clutch is a mechanism used to connect or disconnect the engine from the rest of the transmission elements. It is located between the engine and gearbox. • During normal running and stationary position, it is always in the engaged condition. The clutch is disengaged when the driver processes the clutch pedal. The clutch is disengaged for starting, changing gears, stopping and idling. • When the clutch is engaged, the engine will be connected to the transmission, and power flows from engine to rear wheels through a transmission system. • When the clutch is disengaged by pressing the clutch pedal, the engine will be disengaged from the transmission. Thus, the power does not flow to rear wheels while the engine is still running. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 4 Introduction to clutches continued...
- 5. • Consider twi plates, C and D are atteched to shafts A and B respectively with aim to transmit motion from shaft A to Shaft B. • In the figure (a), when there is a gap between plates C and D, there will be no motion transmission. • Now if small force F is appied to make plate D to connect with plate C, the motion of shaft A starts transmitting to shaft B, because of frictionm between two plates C and D. • This is how clutches work. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 5 Principal of Operation of Friction Clutch... F
- 6. 1. To engage and disengage the transmission from engine to the remaining parts of the transmission. This is required when: (a) Starting and running the engine at a sufficiently high speed lo generate sufficient power necessary for moving the vehicle from rest. (b) Shifting the gears so that damage to gear teeth can be avoided. (c) Stopping the vehicle after applying brakes. 2. The second function of the clutch is to allow the engine to take up the driving load of the vehicle gradually and without shock. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 6 Functions of Clutch...
- 7. • It should be able to transmit the maximum torque of the engine. • It should engage gradually to avoid sudden jerks. • It should be able to dissipate a large amount of heat generated during clutch operation. • It should be dynamically balanced, particularly in the case of high-speed engine clutches. • It should have a suitable mechanism to damp vibrations and to eliminate noise produced during power transmission. • It should be as small as possible so that it will occupy minimum space. • It should be easy to operate requiring as little exertion as possible on the part of the driver. • It should be made as light as possible so that it will continue to rotate for any length of time after the clutch has been disengaged. • It must be trouble-free and have longer life. • It must be easy to inspect, adjust, and repair. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 7 Requirements of Clutch
- 8. The materials for clutch lining are: 1. Leather 2. Cork 3. Fabric 4. Asbestos 5. Raybestos and Ferodo 6. Non- asbestos clutch lining material. Necessity of clutch lining: 1. To transmit maximum power from engine flywheel transmission without jerk 2. To dissipate the heat and able to withstand higher heat generated 3. It should have a higher coefficient of friction 4. It should be cheap and easy to manufacture. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 8
- 9. Main parts of Clutch • DRIVING MEMBER – A flywheel which is mounted on the engine crankshaft. – The flywheel is bolted to a cover which carries pressure plate, pressure springs, and release levers. – As the flywheel is bolted to the cover assembly, thus, the entire assembly of the flywheel and the cover rotate all the time. – The clutch housing and cover provided with openings so that the heat produced during the function dissipates easily • DRIVEN MEMBER – The driven members consist of a disc or plate called a clutch plate. – The clutch is free to slide on the splines of the clutch shaft. – It carries friction materials on both of its surfaces. – When the clutch plate is gripped between the flywheel and the pressure plate, it rotates the clutch shaft through splines. • OPERATING MEMBER – The operating member consists of a pedal or lever which can be pressed to disengage the driving and driven plate. UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 9
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- 11. TYPES OF CLUTCH ACCORDING TO METHOD OF TRANSMITTING TORQUE 1. Positive or Dog Clutch 2. Friction Cluch I. Single Plate Clutch II. Multiplate Clutch III. Cone Clutch IV. Diaphragm Clutch 3. Hydraulic Clutch I. Fluid Coupling II. Hydraulic Torque Convertor UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 11
- 12. TYPES OF CLUTCH Continued.. ACCORDING TO METHOD OF ENGAGING FORCE 1. Spring type clutch 2. Centrifugal clutch 3. Semicentrifugal clutch 4. Electromagnetic clutch ACCORDING TO METHOD OF CONTROL 1. Automatic Clutch 2. Manual Clutch ACCORDING TO METHOD OF OPERATION 1. Cable operated clutch 2. Mechanical linkage operated clutch 3. Hydraulic operated clutch UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 12
- 13. Single Plate Clutch UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 13 • Single plate clutch is the most common type of clutch plate used in automobiles. • It consists only one clutch plate which is mounted on the splines of the clutch plate and assembled to the flywheel and rotates with it. • All the parts and their arrangement id shown in the line diagram. • All the time the clutch plate remains in contact with the flywheel. During gear shifting or starting the vehicle force is applied on the pedal to disengage the clutch plate from flywheel it results interruption in power supply from engine to transmission system of vehicle. • When force from pedal is removed, the power supply is continued to gearbox.
- 14. Multiplate Clutch UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 14 • It is used in heavy vehicles and also in racing cars but most commonly in scooters and bikes. • It consists more than one clutch plate which is mounted on the splines of the clutch plate and assembled to the flywheel and rotates with it. • All the parts and their arrangement id shown in the line diagram. • All the time the clutch plate remains in contact with the flywheel. During gear shifting or starting the vehicle force is applied on the pedal to disengage the clutch plate from flywheel it results interruption in power supply from engine to transmission system of vehicle. • When force from pedal is removed, the power supply is continued to gearbox.
- 15. Cone Clutch UNIVERSITY POLYTECHNIC, GLA UNIVERSITY, MATHIURA 15 • Cone clutch consists of friction surfaces in the form of a cone. • The engine shaft consists of the female cone. • The male cone is mounted on the splined clutch shaft. It has friction surfaces on the conical portion. • The male cone can slide on the clutch shaft. When the clutch is engaged, the friction surfaces of the male cone are in contact with that of the female cone due to force of the spring. When the clutch pedal is pressed, the male cone slides against the spring force, and the clutch is disengaged.