Principle and composition of electronically controlled automatic transmission

The electronically controlled hydraulic automatic transmission is mainly composed of a hydraulic transmission, an auxiliary transmission and an automatic transmission control system, as shown in Figure 6-3.

Hydraulic transmission

Automotive hydraulic transmissions include fluid couplings and torque converters. Modern hydraulic transmissions for automatic transmissions use hydraulic torque converters. The torque converter is mounted on the flywheel of the engine. It transmits power by hydraulic force and can achieve torque increase and deceleration and continuously variable speed within a certain range.

Auxiliary transmission

The auxiliary transmission has two types of planetary gear type and parallel shaft gear type. At present, planetary gear transmissions are widely used. The planetary gear type transmission includes two parts: a planetary gear mechanism and a shift actuator. Its role is to further increase torque reduction. Different gear ratios are achieved by shifting gears to improve the adaptability of the car. The current automobile automatic transmission is generally four forward gears. A reverse gear, gear transmission and torque converter cooperate to form a wider range of continuously variable transmission.

3. Automatic transmission control system

The difference between the automatic transmission control system of the electronic control automatic transmission and the pure hydraulic control automatic transmission control system is that the hydraulic control type automatic transmission converts the valve opening and the speed of the automatic transmission signal into corresponding values ​​through the throttle valve and the governor. The hydraulic pressure is controlled to control the movement of the shift valve to achieve automatic shifting; while the electronically controlled automatic transmission converts the throttle opening and speed into electrical signals through a throttle sensor and a vehicle speed sensor, and is input to a computer. The computer according to the two Signals and other related signals determine the shift timing, output shift electric signals, control the shift solenoid valve action, and then implement automatic shifting through the shift valve and shift actuator.

The shift brake mechanism of the electronic control automatic transmission is similar to that of the hydraulic control type automatic transmission and is also a hydraulic mechanism. Its source of hydraulic power is the automatic transmission oil pump.

Electronic control automatic transmission control process shown in Figure 6-4.

Combined Flow Closed Cooling Tower

Closed Cooling Tower is operated by circulating water or fluid, which is divided into two closed loops.

1. Circulation in the tower: the circulating water or fluid passes through the hot zone environment. After the water temperature rises, it enters the surface cooler in the tower, and the heat is sent to the environment outside the tower through the surface cooler and ventilation fan. The cooled circulating water or fluid is sent to the heat source by the water pump.


2. Circulation outside the tower: the spray water is sent to the spray system by the water tank through the water pipe. After spraying, the spray water first exchanges heat with the filler, so that the spray water can be cooled rapidly. At this time, the water contacts the surface of the surface cooler for heat exchange. Part of the hot steam is discharged through the ventilation fan, and the cooled spray water drops to the water tank for secondary circulation to form an external circulation for cooling.

Combined Flow Closed Cooling Tower,Bac Cooling Tower,Cooling Tower Systems,Chiller Tower

Wuxi Ark Fluid Science Technology Co., Ltd. , https://www.fangzhouarkfluid.com