Patent ID: 7597641

Claim:
A gearing unit ( 20 ) comprising: a casing ( 31 ); an input shaft ( 21 ) having a first end and a second end, the first end of the input shaft ( 21 ) extending out from the casing ( 31 ) and adapted to receive power, the second end of the input shaft ( 21 ) connected to an output shaft ( 42 ) which extends out from the casing ( 31 ); a hydraulic pump ( 22 ) located around the input shaft ( 21 ) and a hydraulic control valve ( 221 ) connected to the hydraulic pump ( 22 ), the hydraulic control valve ( 221 ) communicating with a hydraulic hose ( 41 ) which is connected to an automatic control valve ( 40 ), the automatic control valve ( 40 ) being controlled by a control pedal ( 38 ) and a clutch pedal ( 39 ); an oil tank ( 24 ) connected to the hydraulic motor ( 26 ) and including multiple passages ( 23 ); a hydraulic motor ( 26 ) connected to the hydraulic pump ( 22 ) and located opposite the input shaft ( 21 ), at least one hydraulic pipe ( 25 ) connected between the hydraulic motor ( 26 ) and the hydraulic pump ( 22 ), a worm rod ( 27 ) connected to the hydraulic pump ( 26 ); a rotatable ring gear ( 28 ) located a side of the hydraulic pump ( 26 ) and opposite the hydraulic pump ( 22 ), the rotatable ring gear ( 28 ) located around the input shaft ( 21 ); a fixed ring gear ( 29 ) located on a side of the rotatable ring gear ( 28 ) and opposite the hydraulic motor ( 22 ), the fixed ring gear ( 29 ) located around the input shaft ( 21 ); a circular frame ( 30 ) located between the rotatable ring gear ( 28 ) and the fixed ring gear ( 29 ), the circular frame ( 30 ) located around the input shaft ( 21 ); an output main gear ( 33 ) located in the fixed ring gear ( 29 ) and located around the input shaft ( 21 ); a plurality of output planet gears ( 32 ) located in the fixed ring gear ( 29 ) and located outside of the output main gear ( 33 ); an input main gear ( 35 ) located in the rotatable ring gear ( 28 ) and located outside of the input shaft ( 21 ); an input planet gear ( 34 ) located in the rotatable ring gear ( 28 ) and located around the input main gear ( 35 ), and a worm wheel ( 36 ) located between the rotatable ring gear ( 28 ) and the hydraulic pump ( 22 ), the worm wheel ( 36 ) engaged with the worm rod ( 27 ).