核心部件一：液力變矩器——“軟連接”的動(dòng)力傳遞

Core component one: Hydraulic torque converter - power transmission of "soft connection"

液力變矩器是AT自動(dòng)變速箱非常核心的部件之一，安裝在發(fā)動(dòng)機(jī)飛輪與變速箱輸入軸之間。它的作用相當(dāng)于手動(dòng)變速箱中的離合器，但原理完全不同。

The hydraulic torque converter is one of the most essential components of the AT automatic transmission, installed between the engine flywheel and the transmission input shaft. Its function is equivalent to a clutch in a manual gearbox, but the principle is completely different.

液力變矩器內(nèi)部充滿了變速箱油，由泵輪、渦輪和導(dǎo)輪三個(gè)主要元件組成。發(fā)動(dòng)機(jī)帶動(dòng)泵輪旋轉(zhuǎn)，泵輪攪動(dòng)油液沖擊渦輪，渦輪再帶動(dòng)變速箱輸入軸轉(zhuǎn)動(dòng)——?jiǎng)恿瓦@樣通過(guò)液體“軟連接”傳遞出去。這種傳遞方式帶來(lái)了一個(gè)巨大優(yōu)勢(shì)：車輛起步和停車時(shí)，發(fā)動(dòng)機(jī)可以怠速運(yùn)轉(zhuǎn)而不會(huì)熄火，行駛中的換擋沖擊也被油液吸收，平順性遠(yuǎn)優(yōu)于手動(dòng)變速箱。

The hydraulic torque converter is filled with transmission oil inside, consisting of three main components: pump impeller, turbine, and guide wheel. The engine drives the pump wheel to rotate, which agitates the oil and impacts the turbine. The turbine then drives the transmission input shaft to rotate - power is transmitted through the liquid "soft connection". This transmission method brings a huge advantage: when the vehicle starts and stops, the engine can idle without stalling, and the shifting shock during driving is also absorbed by the oil, making the smoothness much better than manual transmissions.

液力變矩器還具備“增矩”功能——在車輛起步和急加速時(shí)，它能將發(fā)動(dòng)機(jī)扭矩放大，幫助車輛更輕松地起步和超車。當(dāng)車速達(dá)到一定數(shù)值后，變矩器內(nèi)部的鎖止離合器會(huì)鎖止泵輪和渦輪，實(shí)現(xiàn)硬連接，提高傳動(dòng)效率、降低油耗。

The hydraulic torque converter also has a "torque increasing" function - when the vehicle starts and accelerates rapidly, it can amplify the engine torque, helping the vehicle start and overtake more easily. When the vehicle speed reaches a certain value, the lock up clutch inside the torque converter will lock the pump wheel and turbine, achieving a hard connection, improving transmission efficiency, and reducing fuel consumption.

核心部件二：行星齒輪機(jī)構(gòu)——變速的“魔法齒輪”

Core component 2: Planetary gear mechanism - the "magic gear" for variable speed

如果說(shuō)液力變矩器是自動(dòng)變速箱的“離合器”，那么行星齒輪機(jī)構(gòu)就是它的“變速器”。行星齒輪機(jī)構(gòu)由太陽(yáng)輪、行星架（帶行星輪）和齒圈三部分組成。這三者中任意一個(gè)被固定、另一個(gè)作為動(dòng)力輸入、第三個(gè)作為動(dòng)力輸出，就能得到一個(gè)特定的傳動(dòng)比。通過(guò)改變固定、輸入和輸出的組合，一組行星齒輪就能實(shí)現(xiàn)多個(gè)不同的擋位。

If the hydraulic torque converter is the "clutch" of an automatic transmission, then the planetary gear mechanism is its "gearbox". The planetary gear mechanism consists of three parts: the sun gear, the planet carrier (with planet gears), and the ring gear. If any one of these three is fixed, the other serves as the power input, and the third serves as the power output, a specific transmission ratio can be obtained. By changing the combination of fixed, input, and output, a set of planetary gears can achieve multiple different gears.

在實(shí)際的自動(dòng)變速箱中，通常會(huì)串聯(lián)兩組或三組行星齒輪機(jī)構(gòu)，通過(guò)離合器和制動(dòng)器的配合，實(shí)現(xiàn)4至10個(gè)前進(jìn)擋。擋位越多，發(fā)動(dòng)機(jī)就越能在快捷區(qū)間運(yùn)轉(zhuǎn)，動(dòng)力響應(yīng)和燃油經(jīng)濟(jì)性也就越好。

In actual automatic transmissions, two or three sets of planetary gear mechanisms are usually connected in series, and 4 to 10 forward gears are achieved through the cooperation of clutches and brakes. The more gears there are, the more efficient the engine can operate, resulting in better power response and fuel economy.

核心部件三：換擋執(zhí)行元件——合理控制的“操盤(pán)手”

Core component three: Shift actuator - precise control "operator"

有了變速機(jī)構(gòu)，還需要一套執(zhí)行系統(tǒng)來(lái)控制它。換擋執(zhí)行元件主要包括離合器、制動(dòng)器和單向離合器。離合器負(fù)責(zé)將行星齒輪的某個(gè)元件與動(dòng)力輸入軸連接或斷開(kāi)；制動(dòng)器則負(fù)責(zé)將某個(gè)元件固定住；單向離合器只允許元件單向旋轉(zhuǎn)。

With the transmission mechanism, an execution system is also needed to control it. The gear shifting actuators mainly include clutches, brakes, and one-way clutches. The clutch is responsible for connecting or disconnecting a component of the planetary gear from the power input shaft; The brake is responsible for fixing a certain component; The one-way clutch only allows components to rotate in one direction.

這些執(zhí)行元件的動(dòng)作由液壓控制系統(tǒng)和電子控制系統(tǒng)共同指揮。液壓控制系統(tǒng)通過(guò)閥體總成將變速箱油泵產(chǎn)生的油壓分配給各個(gè)執(zhí)行元件；電子控制系統(tǒng)則通過(guò)傳感器采集車速、發(fā)動(dòng)機(jī)轉(zhuǎn)速、節(jié)氣門(mén)開(kāi)度、油溫等信息，由變速箱控制單元（TCM）計(jì)算出非常佳的換擋時(shí)機(jī)，通過(guò)電磁閥準(zhǔn)確控制液壓系統(tǒng)的動(dòng)作。

The actions of these executing components are jointly commanded by the hydraulic control system and the electronic control system. The hydraulic control system distributes the oil pressure generated by the transmission oil pump to various actuator components through the valve body assembly; The electronic control system collects information such as vehicle speed, engine speed, throttle opening, and oil temperature through sensors, and calculates the optimal shifting timing through the transmission control unit (TCM). The hydraulic system is precisely controlled through solenoid valves.