The process of shifting gears in an automatic transmission (automatic transmission)
1. Gear selector
The first step is to select the desired gear using the gear selector located on the center console or steering column.
2. Hydraulic system
When the gear selector is moved, it sends a signal to the hydraulic system. The hydraulic system operates under oil pressure transmitted by a pump.
3. Hydraulic block
The signal from the gear selector is transmitted to the hydraulic unit, which is a set of valves and passages that control the flow of oil. The hydraulic unit interprets the signal and routes it to the appropriate solenoids.
4. Solenoids
Solenoids are solenoid valves that are activated by electrical signals from the hydraulic unit. When the solenoid is activated, it opens or closes the corresponding hydraulic passage.
5. Hydraulic cylinder
A hydraulic cylinder attached to the transmission receives oil pressure from the hydraulic system. Oil pressure pushes the piston in the cylinder, moving the clutches inside the transmission.
6. Couplings
Clutches are mechanical devices that connect the input and output shafts of a transmission. Moving the clutches changes the gear ratio, resulting in a change in vehicle speed.
7. Clutch packs
The clutch packs are located inside the clutches. They consist of alternating friction discs and steel plates. When the clutch is engaged, the clutch packs compress, providing a smooth connection between the shafts.
8. Transfer
When the appropriate clutches are engaged, the transmission input and output shafts are connected, transferring torque from the engine to the wheels.