If you’ve ever driven an automobile with an automatic transmission you are aware of two major differences between an automatic and a manually operated transmission:
- It is impossible to use a clutch pedal inside the automatic transmission vehicle.
- There isn’t any gear shift on an automatic transmission vehicle. When you place the transmission in drive the rest of the operation is completely automatic.
Automatic transmissions (plus their transmission’s torque converter), as well as the manual ones (with their clutch), do similar things, only they accomplish it in completely different ways. The method an automatic transmission uses to do it is absolutely incredible!
We’ll be working to understand an automated transmission. The first step is the most important to the entire system which is the Planetary gearsets. Then, we’ll look at the mechanism of transmission constructed and learn about how it works, and then discuss the complexities involved in controlling a gearbox.
Why Automobiles Need Transmissions
It doesn’t take an expert in technology to comprehend the reason why cars require an engine. It is the force that drives to propel the vehicle.
It is evident that it is essential to transmit the power through the motor to be able in order to propel the vehicle. The mechanism that accomplishes this is known as transmission. There’s more than just a mechanical connection between the drive wheels and the engine.
Internal combustion engines produce energy and power with a limited operating range. This means that the vehicle is equipped with gears that allow the engine to function within its operating range while the vehicle increases speed, attains the same cruising speed, and then slows down. Without this, a car’s ability to speed is severely limited.
In the case of an internal combustion engine vehicle that has a manual transmission drivers change gears. An easy mechanical setup allows the driver to utilize a shift lever to select the particular gear from the various gears that are appropriate to the driving conditions of the moment.
Manually shifting between gears demands regular disconnecting of the engine and reconnecting to the driving mechanism – the propellor shaft and half-shafts which connect to the drive wheels during any drive. Mechanical clutches are the method of disconnecting and reconnecting.
It’s operated with the foot by the pedal of the car’s clutch. Moving gears requires dexterity and physical effort. Although doing it right is fun but it requires effort.
From Manual to Automatic Transmissions
It didn’t take too long for automotive innovators to get started to automate the process of changing gears. This would make driving easier and provide the flexibility and comfort of personal transport for those who lack the ability or the strength to switch gears manually by following the standard procedure.
It wasn’t until the 1930s, that General Motors engineers developed a practical method of automating gear shifts. It was a system that we call today” automatic transmission.
Although it has evolved and been improved over time, most recently with the introduction of electronic controls, the original concept of engineering from the 1930s still remains the core of the automated transmissions that shift gears in our cars, trucks, and SUVs.
Key Components of Automatic Transmissions
Automatic transmissions do something that is easy to explain in terms of. It shifts gears with no guidance from the operator apart from selecting Drive Reverse, Neutral, and Park. However, to make that occur requires a number of components that have to work together under various situations repeatedly. These are the essential factors:
Torque Converter
An electronic torque converter represented a major discovery that led to the development of real-time automatic transmission.
A torque converter basically performs the same function as mechanical clutches perform in manual transmission. It allows for the connection of the engine to the driveline in order for the ease of changing gears.
Fluid dynamics may transfer torque to the engine when required by the vehicle to propel itself forward however it will absorb the torque when moving forward isn’t required.
This option lets you take your car out of Drive when you keep your feet firmly on the brakes when you’re stopped at the stoplight. If you ease off the brake on the car, the torque converter allows the car to accelerate.
Planetary Gears
If your vehicle was equipped with a torque converter, as well as one forward gear, your speed forward will be greatly limited because of the engine operating limit and its torque production capability. This is why changing gears is essential.
Automatic transmissions use a different kind of set of gears than manual vehicles. It utilizes a set of planetary gears in order to produce different ratios of gears, as the hydraulics of an automatic transmission control the gears.
Brake Bands and Clutches
Brake bands and clutches trigger the shifting of gears within the set of gears in the planetary gear set. Brake bands tighten in order to hold the gear in place or loosen up to allow the device to turn. It comes from the mixture of spinning and stationary gears that creates each specific gear ratio.
The transmission’s clutches serve a similar purpose in helping determine what particular ratio of gear the planetary gearset has created at the time. The process of changing the gear ratio to the next requires the tensioning and loosening of clutches and bands. This is controlled by electronics, hydraulics, or a combination of both.
How Automatic Transmissions Works
If you are driving a car that has an automatic transmission, placing the car in Drive triggers the system. When you press your accelerator, the crankshaft of the engine is able to move more quickly, which, in turn, results in increased pressure in the converter.
As the car speeds forward the transmission’s hydraulics and electronic sensors detect the acceleration in conjunction with its engine speed and alter its gears in response.
In the traditional automatic transmission, the hydraulics inside the transmission is able to detect when speeds change. The hydraulics activate the other hydraulics to shift the gears of the gear set planetary.
Nowadays, electronic devices augment this sensing procedure while the auto transmission operates together with the vehicle’s other systems.
When you take your car for a drive be aware there are millions of mathematic calculations that are made into the gear the transmission selected at the time. Your car is performing lots of work each second to make driving more enjoyable for you.