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ACTIVE LEARNING PROCESS. Branch: Computer Engineering. Guided By : Prof. Jugal Panchal. Prepared By :. SIDDHATRH PATEL - 13BECENO55 KARA VINESH - 13BECENO56 TAMBOLI ANUSHA - 13BECEMO57. Brakes and Clutches.
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ACTIVE LEARNING PROCESS Branch: Computer Engineering Guided By : Prof. JugalPanchal Prepared By : SIDDHATRH PATEL - 13BECENO55 KARA VINESH - 13BECENO56 TAMBOLI ANUSHA - 13BECEMO57
Brakes and Clutches • Brakes and clutches are essentially the same devices. Each is associated with the rotation. • Brakes, absorb kinetic energy of the moving bodies and covert it to heat. • Clutches Transmit power between two shafts.
Introduction • Clutches and brakes are essentially the same device • Each provides a frictional, magnetic, hydraulic or mechanical connection between two elements. • Clutches: if both connected elements can rotate; primary function is to transmit power on an intermittent basis. • Brakes: if one element rotates and the other is fixed; absorbs the kinetic energy of moving bodies and controls their motions.
Classification of clutches and brakes • Method of engagement: mechanical, pneumatic & hydraulic, electrical, automatic • Positive contact: square jaw, spiral jaw, toothed • Friction: axial, radial, cone • Overrunning: roller, sprag, spring wound • Magnetic: magnetic particle, hysteresis, eddy current • Fluid coupling: dry fluid, hydraulic
Positive contact clutches • Although not as widely used as friction clutches, do find important use in such applications as automotive transmissions, presses, household appliances. • A synchromesh clutch in a manual automotive transmission: combined with a friction-type clutch, which drags the two elements to nearly the same velocity before the jaws or teeth engages. Automotive transmission typically use helical gears, for quiet operation. The helical gears can not be easily shifted in and out of engagement in manual transmission because of their helix angle. Each gear has a synchromesh clutch connecting it to its shaft.
Friction clutches : Disk clutches • For higher torque capacity, disk clutches are often made with multiple disks to increase the number of friction surfaces, but the heat of friction generated can become the limiting factor on its capacity • Multiple clutches are more difficult to cool, so are appropriate for high load, low speed applications • For high speed dynamic load, fewer friction surfaces are better • Friction clutches may be operated either dry or wet. Oil: reduces the coefficient of friction, increases the heat transfer • Friction coefficients of clutch/brake material combination typically range from 0.05 in oil to 0.60 dry
Clutch • Clutches are a friction based rigid coupling that transmits power by joining two shafts using a friction plate. • Clutches are located on manual cars, automatic cars, ships, and other industrial applications.
Other types of clutches • Cone clutches : another types of axial clutch, being able to transmit a larger torque than disc clutches with the same outside diameter and actuating force, because increased frictional area and the wedging action that takes place. • Cone clutches: low speed applications • Hydraulic or pneumatic clutch can minimize shock and vibration • Centrifugal clutches: engage automatically when the shaft speed exceeds a certain magnitude. Friction elements are thrown radially outward against the inside of a cylindrical drum to engage the clutch.
Important issue , how much force we need to stop the rotation
What are Couplings? • Acoupling is a device used to connect two shafts together for the purpose of transmitting power. • Two types of couplings • Rigid • Flexible also known as compensating
How Does a Coupling Interact With Other Things • Couplings interact with other devices by joining two shafts together in order to transmit power from one shaft to another shaft. Rigid Couplings • Rigid couplings are used when precise shaft alignment is required; shaft misalignment will affect the coupling's performance as well as its life.
Types of Rigid Couplings • Friction coupling • Clutch • Fluid coupling • Torque converter • Hirth joint • High power gas turbines • Flanged • Pipe
Torque Converter • A torque converter in a fluid based rigid coupling used to transmit power from one shaft to another shaft via a fluid median. As the input shaft spins it rotates a turbine causing fluid to move and turn the turbine on the output shaft. • Torque converts are commonly found in automatic cars, hydraulic motors, and turbines.
Hirth Joint • Hirth joints are a type of rigid coupling that transmits power by using two shafts that have interlocking teeth. • Hirth joints are commonly found on high speed high torque industrial machinery that benefits from the Hirth joints self centering capabilities. Common applications include gas turbines, turboprops, steam generators.
Flanged • Flanged couplings are a type of rigid coupling that utilizes flanges and bolts to couple to shafts together. • Common applications of flanged couplings is joining two pipes together in order to transmit water pressure, it can also be used to extend a rotating shaft.
Flexible/Compensating Couplings • Flexible couplings are designed to transmit torquewhile permitting some radial, axial, and angular misalignment. Flexible couplings can accommodate angular misalignment up to a few degrees and some parallel misalignment.
Types of Flexible/Compensating Couplings • Universal joint • Drive shaft on cars • Cardan joint • Train cars • Ball joints • Car steering assembly • Thompson couplings • High torque industrial drive shafts
Universal Joints • Universal joints are a type of flexible coupling that utilized a yoke and cross to connect two shafts and allow shafts to be at an angle relative to each other. • Common application of Universal joints include car drive shafts, steering columns.
Cardan Joint • Cardan joints are a type of flexible coupling that connects two shafts using two pivots and a connecting rod. • Couplings are often used for steering column and ratchet extensions.
Thompson Coupling • Thompson coupling is a flexible coupling that utilizes a configuration of two Cardan joint assemblies, and a modified universal joint • Common application include high power generators, trailer hitches, and gas turbines.
Ball Joint Ball joint is a flexible coupling that uses a spherical ball and socket like configuration in order to allow a shaft to pivot while pivoting. Common applications include car axle assemblies, the human hip joints, throttle bodies, and gas springs.