Multi-gear power gear shifting transmission case

The utility model discloses a multi-gear power gear-shifting transmission case which comprises a transmission case main case and a transmission case auxiliary case. The gearbox auxiliary box is provided with an auxiliary speed change gear shifting mechanism, has a road gear, a field gear, a low-speed gear, a slow gear and four gears including multiple auxiliary speed change gears and three pairs of gears, and is compact in structure and high in gear utilization rate. The gearbox main box is provided with a reversing adjusting mechanism and a main speed changing and gear shifting mechanism, one backward gear and four forward gears are arranged, and gear switching is achieved through separation and combination of different clutches. The gearbox can output 16 forward gears and 4 reverse gears, has multiple gears, is compact in structure, is beneficial to meeting the requirements of agricultural production on tractor gears, is reasonable in speed ratio, can realize power reversing, is simple and convenient to ope