What Is a Gearbox?
A gearbox is the trannsmission in an automobile. There are two main types of gearboxes, called manual transmission (MT) and automatic transmission (AT), respectively.
In a car equipped with a manual transmission, the driver must manually change gears and operate the car. Thus, a car equipped with a manual transmission is called a manual transmission (MT) car or a manual car.
In contrast, a car equipped with an automatic transmission that automatically changes gears is called an automatic car. Currently, automatic transmissions are the mainstream in Japan, and it is said that 98% of all new cars registered in Japan have automatic trannsmission.
Use of Gearboxes
Gearboxes are used to transmit the driving force output from the engine to the tires. Gearbox can run a car more fuel-efficiently without putting a burden on the engine by shifting gears according to the speed of the car and the road conditions.
Specifically, when driving uphill, the gearbox is switched to a lower gear to reduce the rpm. This allows the car to climb hills with power.
On the other hand, when traveling on a flat road, the gearbox converts to a higher gear to allow the car to travel faster and smoother.
Principle of Gearboxes
As mentioned above, there are two types of gearboxes: automatic transmission and manual transmission. Here, we explain the principles and characteristics of each.
Automobiles equipped with a manual transmission are equipped with a clutch pedal. The clutch pedal is used to change gears in a manual transmission vehicle. Specifically, by depressing the clutch pedal, the transmission between the engine and the gearbox is interrupted and the driving force of the engine is not transmitted to the gearbox. In this state, the gearshift is manually operated to change gears. Then, by releasing the clutch pedal again, the transmission between the engine and gearbox is restored, and power is transmitted from the engine to the wheels via the gearbox.
Automatic transmission vehicles are also equipped with shifting gears, but they do not have the clutch pedal provided in manual transmission vehicles. Automatic cars can automatically change gears by selecting the most appropriate gear for the speed, engine speed, and accelerator pedal. Automatic cars can change gears without having to use the clutch pedal to break the transmission between the engine and gearbox. Automatic cars have a device called a torque converter, which, instead of a clutch, transfers the engine’s driving power to the gearbox.