Hydro-mechanical transmission gearbox of special vehicle

The invention relates to a hydro-mechanical transmission gearbox of a special vehicle. The hydro-mechanical transmission gearbox of the special vehicle comprises a box body, an oil system for supplying oil into the box body, a transmission gearbox electric control system. A locking clutch, a hydraulic torque converter, a hydraulic retarder, a low transfer clutch, a high-low transfer planetary pair, a high transfer clutch, a high-gear clutch, a high-middle-gear planetary pair, a middle-gear clutch, a low-gear planetary pair, a low-gear clutch, a reverse-gear planetary pair and a reverse-gear clutch are coaxially arranged in the box body; a turbine speed sensor and an electro-hydraulic gear shift valve group for controlling various clutches to act are arranged on a shell of the box body; thelow transfer clutch is sleeved in a low transfer clutch cylinder sleeve; speed measuring teeth are processed on an excircle of the low transfer clutch cylinder sleeve so as to be matched with the turbine speed sensor to dete