PRESENTION 2 mpp.pptx

7/31/2019 PRESENTION 2 mpp.pptx

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Mohd Zulkhairi Bin Zaidi (15BAD11f1032)Muhammad Nurul Nizam Bin Ahmad (15BAD11F1033 )Khairul Syahreel Bin Osman (15BAD11F1030)Mohamad Adib bin Yusoff (15BAD11F1009)Mohammad Fadzril Aidy Bin Azahar (15BAD11F1001)


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http://en.wikipedia.org/wiki/File:BAUMA_2004_ZF_Differentialgetriebe.jpg


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A differential is a device, usually, but not necessarily,employing gears, which is connected to the outside world bythree shafts, through which it transmits torque and rotation.

The gears or other components make the three shafts rotate insuch a way that, where, and are the angular velocities of thethree shafts, and are constants. Often, but notalways, and are equal, so is proportional to the sum (oraverage)

Except in some special-purpose differentials, there are noother limitations on the rotational speeds of the shafts, apartfrom the usual mechanical/engineering limits.

Any of the shafts can be used to input rotation, and theother(s) to output it. See animation here of a simpledifferential in which and are equal. The shaft rotating atspeed is at the bottom-right of the image.


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In automobiles and other wheeled vehicles, a differentialallows the driving road wheels to rotate at different speeds.

This is necessary when the vehicle turns, making the wheelthat is travelling around the outside of the turning curve rollfarther and faster than the other.

The engine is connected to the shaft rotating at angularvelocity .

The driving wheels are connected to the other two shafts,and are equal.

If the engine is running at a constant speed, the rotational

speed of each driving wheel can vary, but the sum (oraverage) of the two wheels' speeds can not change.

An increase in the speed of one wheel must be balanced by anequal decrease in the speed of the other. (If one wheel isrotating backward, which is possible in very tight turns, itsspeed should be counted as negative.)


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Functional Description

Input torque is applied to the ring gear (blue), which turns the entire carrier (blue).

The carrier is connected to both the sun gears (red and yellow) only through the planet

gear (green). Torque is transmitted to the sun gears through the planet gear. The planet

gear revolves around the axis of the carrier, driving the sun gears. If the resistance at

both wheels is equal, the planet gear revolves without spinning about its own axis, and

both wheels turn at the same rate.
http://en.wikipedia.org/wiki/File:Differential_free.png


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The following description of a differential applies to a "traditional" rear-wheel-drive car ortruck with an "open" or limited slip differential combined with a reduction gearset:

Torque is supplied from the engine, via the transmission, to a drive shaft (British term:

'propeller shaft', commonly and informally abbreviated to 'prop-shaft'), which runs to

the final drive unit that contains the differential. A spiral bevel pinion gear takes its drive

from the end of the propeller shaft, and is encased within the housing of the final drive

unit. This meshes with the large spiral bevel ringgear, known as the crown wheel. Thecrown wheel and pinion may mesh in hypoid orientation, not shown. The crown wheel

gear is attached to the differential carrieror cage, which contains the 'sun' and 'planet'

wheels or gears, which are a cluster of four opposed bevel gears in perpendicular plane,

so each bevel gear meshes with two neighbors, and rotates counter to the third, that it

faces and does not mesh with.
http://en.wikipedia.org/wiki/File:Differential_locked-2.png


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a) Clutch Pack

b) Cone Clutch

c) Torsen


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Two sets of plates make up the clutch pack. These are driving plates and driven plates. The outer driving plates are flat and have external splines that locate in mating splines in

the clutch drum. The inner driven plates have a friction material bonded to them and their splines mate

with splines on the outside of a central hub, which is itself splined to the primary sungear.

The friction material can be of treated paper or fibre and may have a grooved surface to

assist in wiping oil from between the plates when the clutch engages. The plates are placed alternately to make up the pack and are loaded into the clutchdrum against the relatively thick pressure plate.

The central hub is installed to engage the inner plates and thrust washers are placed inposition prior to installing the input shaft.

The large face of the input shaft acts as the final plate in the pack while the splines at itsouter edge transmit the input torque to the clutch drum and the driving plates. The inputshaft is retained in the drum by a large diameter snap ring.

The number of plates installed determines the torque capacity of the clutch. Installingmore plates increases the torque capacity, but in all cases the clutch must maintain itsspecified clearance so that the plates can separate from one another while in the releasedposition.

A centrifugal relief valve in the clutch piston releases fluid trapped in the cylinder whenthe clutch is released. This prevents partial application of the clutch which may becaused by centrifugal force acting on the fluid at high speed.


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A cone clutch serves the same purpose as a disk or plate clutch.However, instead of mating two spinning disks, the cone clutchuses two conical surfaces to transmit torque by friction.

The cone clutch transfers a higher torque than plate or diskclutches of the same size due to the wedging action and increasedsurface area.

Cone clutches are generally now only used in low peripheralspeed applications although they were once common inautomobiles and other combustion engine transmissions.

They are usually now confined to very specialist transmissions inracing, rallying, or in extreme off-road vehicles, although they arecommon in power boats. This is because the clutch does not have

to be pushed in all the way and the gears will be changed quicker.Small cone clutches are used in synchronizer mechanismsin manual transmissions


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http://en.wikipedia.org/wiki/File:Audi_quattro_AWD_system.jpeg


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Torsen (full name Torsen traction) is a type of limited-slip differential used in automobiles.

It was invented by American Vernon Gleasman and manufactured by theGleason Corporation. Torsen is a contraction ofTorque-Sensing. TORSEN and TORSEN Traction are registered trademarks ofJTEKT Torsen North America Inc (formerly Zexel Corporation, formerly

Gleason Power Systems). All Torsen differentials have their origin in theDual-Drive Differential that was invented and patented by Gleasman in1958.

Torsen differentials can be used in one or more positions on a motorvehicle:

center - used to apportion appropriate torque distribution between frontand rear axles on an all-wheel drive vehicle.

rear - used to apportion appropriate torque distribution between left andright sides in rear axles. This may be on either a rear-wheel drive or four-wheel drive vehicle.

front - used to apportion appropriate torque distribution between left andright sides in front axles. This may be on either a front-wheel drive orfour-wheel drive vehicle.

A four-wheel-drive vehicle, for example, may use either one, two, or three

Torsen differentials


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Propeller shaft (prop shaft) is a mechanical component fortransmitting torque and rotation, usually used to connectother components of a drive train that cannot be connecteddirectly because of distance or the need to allow for relativemovement between them.

Drive shafts are carriers of torque: they are subjectto torsion and shear stress, equivalent to the differencebetween the input torque and the load. They must thereforebe strong enough to bear the stress, whilst avoiding toomuch additional weight as that would in turn increasetheir inertia.

To allow for variations in the alignment and distancebetween the driving and driven components, drive shaftsfrequently incorporate one or more universal joints, jawcouplings, or rag joints, and sometimes a splinedjoint or prismatic joint.


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Where the engine and axles are separated fromeach other, as on four-wheel-drive and rear-wheel-drive vehicles, it is the propeller shaftthat serves to transmit the drive forcegenerated by the engine to the axles. Thelonger the shaft, the more liable it is to bend,and bending is further promoted when rotationis applied causing vibrations and resulting in

an increase in noise. For this reason, thepropeller shaft has been designed to suppressvibrations arising from a wide range of causes.


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Single-piece-type Propeller Shaft

2-piece-type / 3-piece-type Propeller Shaft


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Single-piece-type Propeller Shaft

Vehicle models

Used in vehicles with a short distance between theengine and axles, and MR based four-wheel-drive

vehicles. Characteristics

The friction welding adopted at the junctioncontributes to an improvement in the strength,

quality, and durability of the junction. A reductionin the number of component parts and in theweight has been achieved.


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2-piece-type / 3-piece-type PropellerShaft

Vehicle modelsUsed in vehicles with a long distance between theengine and axles, and Front engine front drivebase four-wheel-drive vehicles.

CharacteristicsThe division of the propeller shaft into two- orthree-parts allows the critical number ofrevolution to lowered preventing vibrationproblem from occurring, when the overall lengthof the shaft increased. The dynamicdamper inserted into the pipe reduces thevibration and noise.


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A universal joint, universal coupling, U-joint, Cardin joint, Hardy-Spicer joint, or Hooke'sjoint is a joint or coupling in a rigid rod that allowsthe rod to 'bend' in any direction, and is commonlyused in shafts that transmit rotary motion. It

consists of a pair of hinges located close together,oriented at 90 to each other, connected by a crossshaft.
http://en.wikipedia.org/wiki/File:Universal_joint.gif


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An automobile may use a longitudinal shaft todeliver power from an engine/transmission tothe other end of the vehicle before it goes to the

wheels. A pair of short drive shafts iscommonly used to send power from acentral differential, transmission,or transaxle to the wheels.


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A transfer case is a part of a four-wheel-drive system found in four-wheel-driveand all-wheel-drive vehicles. The transfer case

is connected to the transmission and also to thefront and rear axles by means of drive shafts. Itis also referred to as a "transfer gearcase","transfer gearbox","transfer box" or "jockey

box".


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The transfer case receives power from the transmission and sends it to both thefront and rear axles. On some vehicles, such as four-wheel-drive trucks orvehicles intended for off-road use, this feature is controlled by the driver. Thedriver can put the transfer case into either "two-wheel-drive" or "four-wheel-drive" mode. This is sometimes accomplished by means of a shifter, similar tothat in a manual transmission.

An on-road, transfer case synchronizes the difference between the rotation of thefront and rear wheels, in much the same way the differential acts on a given axle.This is necessary, because the front and rear tires never turn at the same speedwhen front and rear tire sizes differ.

Transfer cases designed for off-road use can mechanically lock the front and rearaxles when needed (e.g. when one of the axles is on a slippery surfaces or stuckin mud, whereas the other has better traction).

The transfer case may contain one or more sets of low range gears (generally foroff-road vehicles). Low range gears are engaged with a shifter or electronicswitch. On many transfer cases, this shifter is the same as the one that selects2WD or 4WD operation. Low range gears slow down the vehicle and increase thetorque available at the axles. Low-range gears are used during slow-speed orextreme off road maneuvers, such as rockcrawling, or when pulling a heavy load.This feature is often absent on all-wheel-drive cars.


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An axle is a central shaft for a rotating wheel or gear. On wheeledvehicles, the axle may be fixed to the wheels, rotating with them,or fixed to its surroundings, with the wheels rotating around theaxle. In the former case, bearings or bushings are provided at themounting points where the axle is supported. In the latter case, abearing or bushing sits inside the hole in the wheel to allow the

wheel or gear to rotate around the axle. On cars and trucks, several senses of the word "Tandem axle" co-

occur in casual usage, referring to the shaft itself, its housing, orsimply any transverse pair of wheels. The shaft itself rotates withthe wheel, being either bolted or splined in fixed relation to it, andis called an "axle" or "axle shaft". However, it is equally true that

the housing around it (typically a casting) is also called an "axle"(or "axle housing"). An even broader (somewhat figurative) senseof the word refers to every transverse pair of wheels, whether theyare connected to each other or not. Thus even transverse pairs ofwheels in an independent suspension are usually called "an axle"

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PRESENTION 2 mpp.pptx