變速箱是汽車動力傳輸的核心部件，其作用是通過調整齒輪比，平衡發動機轉速與車輪扭矩，從而適應不同駕駛場景。從傳統機械到電子智能，變速箱技術經歷了多次迭代。本文將系統介紹主流變速箱類型及其技術特點，幫助讀者理解其工作原理與適用場景。

The gearbox is the core component of automobile power transmission, which adjusts the gear ratio to balance the engine speed and wheel torque, thus adapting to different driving scenarios. From traditional mechanical to electronic intelligence, gearbox technology has undergone multiple iterations. This article will systematically introduce the mainstream transmission types and their technical characteristics, helping readers understand their working principles and applicable scenarios.

一、手動變速箱（MT）：駕駛樂趣的“原始基因”

1、 Manual Transmission (MT): The "Primitive Gene" of Driving Pleasure

手動變速箱（Manual Transmission）是最基礎的變速機構，由離合器、齒輪組和換擋桿組成。駕駛者需通過踩離合、撥換擋桿手動切換齒輪比。其優勢在于結構簡單、傳動效率高（可達95%以上），且維修成本低。例如，五菱宏光MINI EV的手動版憑借低門檻操作，成為駕校教練車首選。但缺點是操作繁瑣，城市擁堵路況下易疲勞。隨著自動擋普及，MT逐漸退居入門級車型或性能車市場（如保時捷911 GT3保留MT以強化操控感）。

A manual transmission is the most basic transmission mechanism, consisting of clutches, gear sets, and shift levers. Drivers need to manually switch gear ratios by stepping on the clutch and shifting the gear lever. Its advantages lie in its simple structure, high transmission efficiency (up to 95% or more), and low maintenance costs. For example, the manual version of the Wuling Hongguang MINI EV has become the first choice for driving school coaches due to its low threshold operation. But the disadvantage is that the operation is cumbersome and prone to fatigue under congested urban road conditions. With the popularity of automatic transmission, the MT gradually retreated to the entry-level or performance car market (such as the Porsche 911 GT3 retaining the MT to enhance handling).

二、自動變速箱（AT）：舒適與可靠的“平衡大師”

2、 Automatic Transmission (AT): A Comfortable and Reliable 'Master of Balance'

自動變速箱（Automatic Transmission）通過液力變矩器與行星齒輪組實現自動換擋，無需駕駛者干預。其核心部件液力變矩器可緩沖發動機沖擊，提供平順的起步體驗。例如，豐田愛信6AT因換擋邏輯聰明、可靠性高，被廣泛應用于卡羅拉、漢蘭達等車型。現代AT變速箱通過多擋位設計（如采埃孚8AT、奔馳9AT）提升燃油經濟性，但結構復雜導致成本較高，維修難度大于MT。

Automatic transmission achieves automatic shifting through a hydraulic torque converter and planetary gear set, without the need for driver intervention. Its core component, the hydraulic torque converter, can cushion engine impact and provide a smooth starting experience. For example, the Toyota Aisin 6AT is widely used in models such as Corolla and Highlander due to its intelligent shifting logic and high reliability. Modern AT transmissions improve fuel economy through multi gear design (such as ZF 8AT, Mercedes Benz 9AT), but the complex structure leads to higher costs and greater maintenance difficulty than MT.

三、無級變速箱（CVT）：平順經濟的“節能專家”

3、 Continuously variable transmission (CVT): a smooth and economical "energy-saving expert"

無級變速箱（Continuously Variable Transmission）采用鋼帶或鏈條連接兩組錐形輪，通過改變輪徑比實現連續變速，理論上擁有無限擋位。其優勢在于換擋無頓挫，且能始終讓發動機保持在最佳效率區間。例如，日產軒逸搭載的CVT變速箱可使綜合油耗低至5L/100km。但CVT的鋼帶承受扭矩有限，多用于小型車或混動車型（如豐田卡羅拉雙擎），且急加速時易出現“打滑”現象，影響駕駛激情。

A continuously variable transmission uses steel strips or chains to connect two sets of conical wheels, and achieves continuous shifting by changing the wheel diameter ratio, theoretically having infinite gears. Its advantage lies in the absence of jerks during gear shifts and the ability to consistently maintain the engine in the optimal efficiency range. For example, the Nissan Sylphy is equipped with a CVT gearbox that can reduce the overall fuel consumption to 5L/100km. However, the steel strip of CVT has limited torque capacity and is mostly used for small cars or hybrid models (such as Toyota Corolla dual engine), and it is prone to "slip" during rapid acceleration, which affects driving passion.

四、雙離合變速箱（DCT）：性能與效率的“雙面手”

4、 Dual clutch transmission (DCT): a "dual hand" of performance and efficiency

雙離合變速箱（Dual Clutch Transmission）結合了MT與AT的特點，通過兩組離合器分別控制奇數擋與偶數擋，實現毫秒級換擋。其干式版本（如大眾DQ200）成本低，但散熱差；濕式版本（如大眾DQ381）通過油液冷卻，可承受更大扭矩，多用于高性能車（如奧迪S3）。DCT的傳動效率接近MT（可達92%），但低速蠕行時易產生頓挫，需通過軟件優化改善。

The Dual Clutch Transmission combines the characteristics of MT and AT, controlling odd and even gears through two sets of clutches to achieve millisecond level shifting. Its dry version (such as Volkswagen DQ200) has low cost, but poor heat dissipation; The wet version (such as Volkswagen DQ381) can withstand greater torque through oil cooling and is commonly used in high-performance cars (such as Audi S3). The transmission efficiency of DCT is close to MT (up to 92%), but it is prone to jerking during low-speed creeping and needs to be improved through software optimization.

五、序列式變速箱（SMG）：賽道專屬的“暴力機器”

5、 Sequential Transmission (SMG): A Track Exclusive 'Violent Machine'

序列式變速箱（Sequential Manual Gearbox）常見于賽車，通過推拉換擋桿實現順序升擋/降擋，無需離合器操作。其換擋速度極快（可低于50毫秒），但頓挫感強烈，且無法跳擋（如無法從3擋直接降至1擋）。法拉利SF90 Stradale的8速序列式變速箱專為賽道設計，兼顧高速競技與日常駕駛，但民用車型極少采用。

Sequential Manual Gearbox is commonly used in racing cars, which achieves sequential upshifts/downshifts by pushing and pulling the shift lever, without the need for clutch operation. Its shifting speed is extremely fast (can be less than 50 milliseconds), but it has a strong jerking sensation and cannot jump gears (such as not being able to directly shift from 3rd gear to 1st gear). The 8-speed sequential transmission of the Ferrari SF90 Stradale is designed specifically for racing tracks, balancing high-speed competition and daily driving, but it is rarely used in civilian models.