In a typical automatic transmission, for example, a hydraulic control signal control apparatus according to the throttle (accelerator) opening and the transmission output shaft to the lifting gear transport. Acceleration produced according to the throttle opening variation, hydraulic valve control device pedal depression amount proportional hydraulics, the hydraulic throttle opening as a "signal" to the hydraulic control device; another speed controlled hydraulic valve fitted in the output shaft can generate a hydraulic speed (the speed) is proportional, as vehicle speed "signal" is added to the hydraulic control device. Thus, there is a throttle opening "signal" and the vehicle speed "signal", the hydraulic control apparatus according to the two "signals" automatically adjust transmission oil, thereby controlling the shift timing.
That is in the car driving, the driver depresses the accelerator pedal (accelerator pedal), control the throttle opening and the vehicle traveling speed (transmission output shaft speed), can automatically control the hydraulic control unit within the transmission, hydraulic control device We will make use of hydraulic clutches and brakes to control the planetary gear system to change the state of the planetary gear drive.
The core of the automatic transmission control device is a hydraulic control means, the control means comprises a hydraulic pump, valve, clutch, brake and the connection of all these parts consisting of the liquid passage. The key component is a valve body, so it is the center of the automatic transmission control valve the role of the body is based on the chassis, engine and drive train load conditions (the throttle opening and the output shaft speed) of the hydraulic pump output to be controlled by the implementing agencies to control the torque converter, controls the clutches and brakes The combination and separation automatic shifting.
These are the basic form of control automatic transmission, electronically controlled automatic transmission if it is, we must increase the electromagnetic valve based on the above, ECU (electronic control unit) by means of a solenoid valve controlling the automatic transmission work process .ECU input circuit accepts input sensors and other devices signal, the signal filtering and amplification, and then converted into electrical signals driving the solenoid valve operation controlled. Therefore, electronically controlled automatic transmission will increase the throttle position sensor, vehicle speed sensor, temperature sensors, hydraulic temperature sensor, engine speed sensors, position switch, brake light switch, digital signal import ECU, allowing ECU precisely controls the solenoid valves, the shift and the locking time accurate, making cars run more smoothly and save fuel. |
