QJM series internal curve radial Steel ball hydraulic motor It is the radial flow distribution of high-pressure hydraulic oil through the oil distribution shaft. Under the axial drive of high-pressure oil and the reaction force of stator, the piston steel ball components drive the rotor to form a rotary motion. In all operation cycles, the oil distribution shaft, stator and rotor are important parts, which will directly affect the technical parameters and service life of the motor.

1、 Operating principle

Hydraulic motor The structure is composed of stator, piston parts, rotor, oil distribution shaft, etc. The dark color is high-pressure oil, and the light color is low-pressure oil. The stator has 6 action frequencies, the number of piston parts is 10, the number of oil inlet and outlet of the oil distribution shaft is 12, the plunger process is the radial spacing between the peaks and troughs of the single action curve of the stator, and the piston parts are distributed in the rotor hole. When the multi way reversing valve operates to feed oil, the high-pressure oil passes through the annular flow channel of the oil distribution shaft to drive the piston to cling to the slide rail. The reaction force of the slide rail on the piston element drives the rotor to rotate, converts the pressure into mechanical kinetic energy, and transmits it to the external device through the reserved internal spline hole of the rotor. The low-pressure oil flows directly back to the oil tank through the oil discharge port.

2、 Oil distribution shaft

The oil distribution shaft adopts the radial flow distribution structure. The oil distribution shaft is placed in the rotor with a high-precision assembly clearance, which determines the volume efficiency of the motor. Its upper end face is provided with threads connecting the oil inlet and outlet holes, and the oil distribution shaft is radially provided with a flow distribution window and two incoherent high-pressure and low-pressure annular flow paths, which play the role of high-pressure and low-pressure oil path configuration. When the hydraulic pump pushes the high pressure oil to flow through the high pressure passage, it acts on the stator through the piston assembly to do work. Under the return oil pressure, the low pressure oil makes the piston steel ball close to the stator to return and drain oil to avoid impact. In order to improve the processability of the high-pressure and low-pressure annular passage of the oil distribution shaft, the mandrel heat sleeve is selected to cooperate with each other, that is, the inner cavity of the oil distribution shaft is produced and processed into an annular groove, which forms the high-pressure and low-pressure passage through the mandrel heat sleeve. The greater the temperature and pressure inside the motor, the more the shrink fit of the hot sleeve. If the shrink fit or the strength of the shaft is small, internal leakage will often occur, causing problems such as weak motor rotation, low speed and creeping. If the interference is too high, it will be difficult to install, or even crack. In mass production, precise temperature control, high thermal effect and precise specifications of parts are required. Therefore, the oil distribution shaft is heated in an oven, and the temperature of the heat jacket must be higher than the normal operating temperature of the workpiece, generally controlled at about 200 "C. After long-term market tracking and user evaluation, motor applications are abnormal. Most motors are weak in rotation and have serious internal leakage. By comparison, because the brake controller appears in front of the oil distribution shaft, the brake butterfly spring has always been in a state of force, high heat occurs when rotating, and the hydraulic oil trapped here has low liquidity, so the heat dissipation condition is poor, which is the most extreme range of the motor working environment. The oil distribution shaft and rotor are both made of ductile iron. Under the condition of heat, the assembly clearance is expanded, and the temperature in front of the oil distribution shaft is high. Therefore, the motor is severely damaged and the leakage is increased during operation. In this range of the oil distribution shaft, the originally expanded gap is compensated by copper surfacing, which controls the leakage. The expanded copper surfacing plays the role of rotor centering, and can also ensure that the damaged abrasive particles are well contained in the welding copper after all operations of the motor. The processing process of oil distribution shaft is as follows: casting annealing rough turning inner hole and outer circle normalizing rough turning surfacing steps surfacing rough turning surfacing fine turning outer circle and inner hole drilling various holes fine turning oil threaded hole drilling milling groove hot sleeve shaft fine grinding outer circle deburring inspection, cleaning and warehousing.