Hello, guys, I am here to tell you about transmission in cars, which is the basic module of an automobile. A transmission is a machine with a powertrain mechanism that transmits the power developed by the engine to the axle. The transmission is used to reduce the revolutions of the crankshaft down to a reasonable value by using interlocking gears. Doing so makes more effective usage of the engine’s torque and helps to keep the engine operating at an appropriate speed. We all know manual and automatic transmission, but there are more types of transmission.
1) Manual Transmission
This is the primary Transmission type it uses a manual clutch and the driver has to change gears and engage the gear ratios. Without a clutch, it is impossible to change gear when the engine is running cause the crank is rotating continuously, The clutch is a coupling device that is used to separate the engine and transmission which allows changing gear. It is easy to use just press the clutch pedal and shift the gear, It could be difficult for new drivers to manage the clutch and drive in real-life conditions, but a car enthusiast will love it.
2) Automatic Transmission
The gear shifting is automatic and the gear ratios are engaged by the car’s computer, the driver is relieved from changing gear and pressing the clutch. The more gears the transmission has, the smoother the acceleration of the vehicle. AT is one of the most successful transmissions of today’s automobile industry. It is easy to use just press the brake and put in P(park)-R(reverse)-N(neutral)-D(drive), It becomes hassle-free to drive in traffic. AT is really easy for the new drivers. Though the performance and fuel economy do not match that of a manual transmission, it is getting better with the improvements in the automatic transmission in present times.
There are 4 common types of automatic transmission
1) Continuously variable transmission(CVT)
It is a better version of the automatic transmission also known as a single-speed transmission, it offers a better fuel economy and smoother driving experience. The major difference is it does not have gears, this system uses belts and pulleys to produce an infinite range of ratios. It has a computer that adjusts the pulley to get the best gear ratio, which in return has good fuel economy. One pulley is connected to the engine (input shaft) and the other to the drive wheels (output shaft).
The diameter of the pulley varies the transmission’s ratio. Making the input pulley smaller and the output pulley larger gives a low ratio (a large number of engine revolutions producing a small number of output revolutions) for better low-speed acceleration and vice versa. As the car accelerates, the pulleys vary their diameter to lower the engine speed as the car speed rises.
It has various advantages :
- Step-less transmission
- High fuel economy
- Smooth drive
- Better emission control
There are some drawbacks :
- Limited amount of torque
- High wear
- High cost
- Weird continuous noise like the car is driving in one gear
Courtesy: Thomas Schwenke
2) Automated Manual Transmission(AMT)
It is just a manual transmission that works with the electronically controlled (microprocessor-based) clutch. It has a drive mode D(drive) N(neutral) R(Reverse) gear system just like automatic, but it also has the manual option with + for upshift and – for downshift. Without the manual clutch, it helps the driver to be less tired in traffic. It has the best of both worlds easy to drive and fun to drive.
- Easy to drive
- Better fuel economy
- Reasonable price
- Jerky shifts
- Unplanned upshifts and downshifts
- Even after having a manual control, you really can’t rev at high RPM
3) Dual Clutch Transmission (DCT)
The name itself says it has two clutches. One clutch handles odd gears and the other the even gears. When you are accelerating in the third gear the computer will pre-select the fourth gear and it will deselect the odd clutch and select the even clutch, this reduces the shifting time which improves the performance and fuel efficiency. The same will happen if you’re braking from the fourth gear, it will pre-select the third gear deselect the even clutch and select the odd clutch. In this system there is constant power flow even during the transition, therefore is no power loss during the transition.
- Quick shifts
- Good for performance driving, as you get more horsepower at the wheels
- Good fuel economy
- High initial cost and Expensive to replace
- Complex system
4) Torque Converter
This mechanism uses an advanced fluid coupling for increasing torque generated by the engine and sending power to the wheels, torque converters are also known as torque converter automatics. A torque converter is one of the oldest types of automatic transmission on a car and is an engineering marvel.
You’ll notice that the clutch is missing on a car with torque converter transmissions, this transmission system will work by connecting two turbines one to the engine and one to the drive. The hydraulic fluid between these two turbines transfers energy from a turbine on the engine’s side to one on the transmission section, which in turn causes vehicle movement. Cars with torque converter transmission are easy to drive and have plenty of torque from very low RPM for smooth acceleration. They are one of the oldest forms of automatic transmission and are complex
- Less wear on components
- Smooth drive
- Expensive to repair
- Not good for fuel economy
iMT (Intelligent Manual Transmission)
As the name suggests, the intelligent part is of the clutch which is maintained by the computer on board. You only need to shift gears without pressing the clutch manually. I know it sounds a bit odd, but that’s what it does. You can call this a semi-automatic transmission.
This system uses sensors on the gear lever which sends the signal to the hydraulic clutch actuator, and an electronic transmission control unit to press the clutch when the driver is about to change the gear. It was developed to make driving easy with the fun of changing gear.
- Easy to drive
- Better fuel economy
- Not very reliable
- Expensive than Manual transmission
I personally love manual transmission cause it adds more fun when you are driving. For new drivers, Automatic transmission is the best option. But the best is the DCT which adds performance and fun making driving easy in any condition. Hope now you have a better understanding of different types of transmission, you can let us know if you have any questions or comments