Working principle of gear pump
The inlet oil is filled in the rotating gear groove and extruded along the inner surface of the casing to the outside of the gear.
The oil between the output side and the suction side can only be discharged when the two gears are meshed. The output pressure is set at 5.2kpa, and the compressed oil is delivered to the main pump and pilot circuit.
1. Structure and principle of rotary motor assembly
(1) structure of rotary motor assembly
The rotary motor assembly includes a valve cover part, a rotary motor part and a rotary reduction gear part. The valve cover part includes rotary parking brake, crossover valve and auxiliary valve. The structure of the rotary motor assembly is shown in Fig. 2-42.
The rotary motor is a swashplate axial piston motor. The rotary motor is composed of swash plate, hydraulic cylinder group, piston with intermediate bush, valve plate, parking brake and motor shell.
Each piston is equipped with brake shoe, and nine pistons with brake shoe are inserted into the hydraulic cylinder. Nine pistons are supported by the swash plate and slide on the viewing surface of the swash plate. The hydraulic pressure makes the piston move in a straight line in the hydraulic cylinder group, and produces a rotating force to make the hydraulic cylinder rotate.
Since the hydraulic cylinder group is connected to the output shaft with a needle, the rotating force of the hydraulic cylinder group is transmitted to the output shaft. The rotation force of the output shaft is transmitted to each rotating gear through the rotating reduction gear.
(2) working principle of rotary motor
The casing part includes the air defense valve and cross valve. The high pressure oil enters the rotary motor through port a or port B in the direction of rotation. The oil path of high pressure port and low pressure port of rotary motor is shown in Fig. 2-43.
Each piston is connected to the sliding block by ball or sleeve joint. When the oil is squeezed into the top of the piston, the slider slides around the thrust plate, causing the motor to rotate. The shield is fixed against the plate by spring force. The oil flows into or out of the piston through the fixed valve plate.
Rotary motor is a fixed displacement motor, its rotation speed is increased or decreased according to the amount of oil delivered to the rotary motor.
Source: Jiangmen construction machinery accessories manufacturer http://www.hx-machinery.cn/