Transcript for:
Understanding Car Transmissions

[Music] a car transmission is one of the most important components of a vehicle it moves the power from the engine to the wheels there are a variety of car transmissions some are automatic and some are manual transmissions as stick shift cars in which the driver required to complete extra steps to operate the vehicle effectively if you have wondered how does a transmission work the process varies depending on the type of transmission but what does a transmission do transmission in a vehicle enables the gear ratio between the drive wheels and engine to adjust the car speed from slowing down and speeding up when a vehicle is stopped the transmission disconnects the engine from the drive wheels so that the engine can keep idling when the wheels aren't in motion transmissions also enable quick acceleration from a stop and enable the engine to run slowly to cut down on wear while the vehicle is driving at consistent speeds there are four different types of transmissions that we generally see some of which you probably have more experience with than others here are the different types of transmissions and the pros and cons of each of them manual transmission manual transmissions have a clutch pedal and a shifter which the driver uses to change the gears manually these types of transmissions consist of a set of gears along a pair of shafts called the input and output shafts with a manual transmission the driver has to select the proper gear and engage or disengage the clutch pedal the transmission uses a flywheel pressure plate and clutch to engage and disengage the engine from the transmission the flywheel and pressure plate are connected to the engine the clutch is sandwiched between them and is splined to the transmission input shaft the term push in the clutch means to release the pressure plate which disengages the clutch from the engine every time you make a shift you have to push in the clutch first here are some pros of manual transmissions better for off-road and high torque load usage reliable and easier to service maintain and repair not everyone can drive cons of manual transmissions not everyone can drive which means lower resale and higher learning curve more work is required during driving intelligent manual transmission or imt simply and quite accurately put the imt is a clutchless manual transmission it's just a regular manual gearbox but without a clutch pedal in situations like coming down a slope or overtaking you have full control over the gearbox and this is of course without the headache of operating the clutch pedal you don't need to lift off the accelerator when shifting gears it will help smooth in things if you do and imt cannot shift gears automatically the benefits of in this transmission is that in this way you have a complete control over what gear your car is in and you don't have to rely on the software getting it right another advantage is that the cost of an imt is also closer to that of a regular manual transmission the main drawbacks of an imt is that the gear shifts aren't as smooth as the system relies on a single clutch that has to be modulated by an actuator amt or automated manual transmission is mechanically similar to a manual transmission except that the sensors and actuators perform the clutch work and shift gears a car with an amt does not have a clutch pedal there's only the accelerator and brake pedal this transmission also allows manual gear shifts when needed by pushing forward the gear lever for up shift and pulling it backward for downshift amt transmission uses hydraulics and computers linked with the electronic control unit or ecu of the car the gear shift patterns are pre-programmed on this unit and work mainly on the preset rpm range once the system gauges optimum rpms the ecu engages the actuators which operate the clutch and gearbox a significant benefit of amt over manual transmission is its convenience since operating the clutch is not part of the driver's task it reduces fatigue in comparison to automatic transmission amt is more fuel efficient it allows more of the engine's energy to flow to the wheels on the other hand however since amts rely on preset rpm levels they can make unplanned up shifts during overtaking which can be unnerving the very basic knowledge that everyone has that an automatic transmission changes gear automatically and doesn't need a gear stick or clutch operation by the driver the engine connects to a torque converter which is then connected to a gear system and then to the transmission a torque converter is a vital component of an automatic transmission inside the torque converter there are parts that work in tandem with each other the outermost side has the flywheel which is connected to the engine it rotates the entire structure the rotation makes the pump push out fluid at high speed this fluid makes the turbine rotate the fluid keeps on rotating separated in two sections and is kept rotating with the help of a stator in the middle the turbine is connected to the shaft which connects to the rest of the system and then the energy is transferred to the gear system in a planetary gear system a star is followed around by the planets and rotate around it at respective speeds the gear system is called a planetary gear system which consists of a gear in the middle called the sun gear and three gears around it called planetary gears which are covered by a ring gear the planetary gears are smaller than the sun gear the speed at which sun gear rotates will be slower than the planet gear making the ring gear rotate faster than the sun gear these parts in combination makes an automatic transmission the first automatic transmission used in a production car was the hydromatic oldsmobile model in the 1940s most large suvs and trucks have traditional type of automatic transmissions here are some pros of automatic transmissions easy to use comfortable driving for driver and passengers here are some cons of automatic it is a complex system where many different items can fail too expensive to maintain and repair compared to manual transmission continuously variable transmissions are also called as cvts these are pulley-based transmissions that are primarily used in small vehicles with small engines this transmission have been used for years in snow machines and are also becomes more popular in hybrid vehicles recently the cvt offers a similar driving experience to an automatic transmission but operates using a completely different mechanism in fact it doesn't have gears at all instead it uses a system of belts and pulleys to produce an infinite range of ratios the computer fitted in these cars decides how to adjust the pulleys to create the optimal ratio for the particular driving situation this system is consists of cones at each pulleys connected by a chain belt the cones can move to increase or decrease the belt diameter to change gear ratios one pulley is connected to the engine and the other directs power to the wheels the width of these pulleys changes based on the needed power as one gets larger the other gets smaller this allows a cvt to deliver strong and seamless acceleration here are some pros of continuously variable transmission smoothest ride because it eliminates feeling of shifting great fuel efficiency because engine is always running efficiently faster response to a change in driving conditions cons of continuously variable transmission unusable in off-road conditions no ability for the engine braking seen in manual transmissions semi-automatic transmissions it is a clutchless manual transmission that provides an alternative to its automatic or manual counterparts this transmission is practically identical to a manual one in a typical manual vehicle the driver steps down on the clutch pedal when they want to change gears the clutch pedal is connected to the transmission through cables and pipes in a semi-automatic there is no clutch pedal instead there is a computer that uses processors and sensors to automatically depress the clutch when the driver signals by shifting the gear stick the vehicle's computer manages engine torque speed accelerator pedal position and other functions driving a semi-automatic car would feel very similar to a manual drive except that you don't have to press on the clutch pedal to change gears although semi-automatics do have things in common with other typical transmissions and they are also very different with their own set of benefits and drawbacks here are some pros of semi-automatic transmissions smooth shifting compared to manuals less inefficiencies in shifting mean no lag time or slippage cons of semi-automatic transmissions complex system which means many different items can fail expensive to maintain compared to manual very expensive to repair often it's more cost effective to just replace dual clutch transmission in a dual clutch transmission there are separate clutches for both odd and even gears which allows for incredibly fast shifts these gearboxes can generally operated in a fully automatic mode or manually shifted with paddles on the steering wheel semi-automatic and dual clutch transmissions offer cutting edge performance with lightning fast gear changes that a pure manual just can't match currently these gearboxes are mainly found on race cars and high-end sports cars and they are quite expensive this disadvantage is magnified by their extreme complexity which leads to more frequent and costly repairs so that's it this is my thoughts on transmissions i hope this helps you to understand about how different transmission works if you still have any queries or do you think i have missed anything then please let me know in the comments and do visit our website for more information you