Hydraulic motor gear pump with impeller arranged on inlet for pressurizing liquid supply

The invention discloses a hydraulic motor gear pump with impeller arranged on inlet for pressurizing liquid supply. The hydraulic motor gear pump is an integrated body of a motor, a centrifugal pump impeller and a gear pump; an oil inlet is provided with an impeller, and oil liquid reaches an oil suction port of the gear pump after being pressurized, so that the problem of insufficient oil absorption of the gear pump is well improved, especially at higher rotating speed, the oil absorption efficiency of the gear pump is improved more obviously, and meanwhile, cavitation noise generated due toinsufficient oil absorption is also avoided; and a motor rotor (10) is mounted on a main shaft (7) through an interference fit, a first bearing (8) and a second bearing (19) are supported on a housing(1), and a gear set (4) is mounted on a front end cover (3), is connected with the main shaft (7) through a first flat key (5), an impeller (16) is arranged between a rear end cover (15) and an innerend cover (14) and is conn