What are the components of the shift actuator in automatic transmission and what is its function?

In automatic transmission, shift actuator includes manual selector valve operating mechanism and throttle operating mechanism.

The driver changes the position of the manual valve in the valve plate through the operating handle of the automatic transmission. According to the position of the manual valve, the throttle opening, the vehicle speed and the state of the control switch, the control system adopts hydraulic automatic control or electronic automatic control to control the work of the shift actuator in the shift transmission according to certain rules, so as to realize automatic shift.

In the hydraulic control system, adding a solenoid valve to control part of the hydraulic circuit becomes a shift control system controlled by electrical appliances. If these solenoid valves are controlled by electronic computers, it becomes an electronically controlled shift control system.

Extended data

Automatic transmission oil is pumped from the oil pump and enters the main oil system. Because the oil pump is directly driven by the engine, its output flow and pressure are affected by the operation of the engine. When the engine is running, the speed changes from 1000r/min, which makes the output flow and pressure of the oil pump change greatly.

Too high main oil pressure will cause shift impact and increase power consumption, and too low main oil pressure will cause clutch brake to slip, both of which will affect the work of hydraulic system, so the main oil pressure regulating valve must be set in the main oil system.

When the car is driving, as long as the road and traffic conditions permit, it is necessary to shift into a higher gear in time. Be sure to accelerate the "rush" before shifting gears to ensure that there is enough power to keep the car running smoothly after shifting gears.

"Rush" (speed) is too small (low), which will cause insufficient power and jitter after shifting; If the "rush" time is too long, the engine will run at high speed for a long time, which will aggravate wear and reduce economy.

Therefore, the "rush" should be appropriate and the shift should be timely. The timing of gear shifting should be determined according to the engine sound, speed and power. If you step on the accelerator after gear shifting, the engine speed drops and the power is insufficient, indicating that the timing of gear shifting is too early.

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