(2) Cycloid internal gear motor this paper mainly introduces several typical structures of planetary rotor type cycloid internal gear motor. There are many kinds of this kind of motor, which can be divided into three types according to the different flow distribution methods: axial flow distribution, end flow distribution and valve flow distribution; according to the structure of the stator, it can be divided into two types: cycloidal motor with integral stator and cycloidal motor with assembled stator.
① The cycloid motor with axial distribution has the characteristics of simple structure, small size and low requirement for oil filtration accuracy. The cycloidal motor with axial distribution can be divided into two types: distribution shaft and distribution sleeve.
Figure K shows the structure of the cycloid hydraulic motor with distribution shaft. The cycloid rotor 14 with Z1 teeth is meshed with the stator 13 with 22 arc teeth to form Z2 closed volumes. The transverse grooves a and B on the valve distribution shaft (output shaft) 7 are connected with the oil inlet. There are two groups of longitudinal oil grooves 2z1 on the surface of the valve distribution shaft. One group (z1) is connected with a and the other group (z1) is connected with B. There are 22 holes C in the housing 6, which are respectively communicated with the tooth bottom of the stator (i.e., communicated with 22 sealing volumes) through the corresponding 22 holes D of the auxiliary valve plate 10. Under the action of pressure oil, the increased volume of the sealing cavity of the rotor is filled with high pressure oil through the port shaft to make the motor rotor rotate, and then the rotation is transmitted to the output shaft through the spline coupling 8. The other sealing cavities with smaller volume discharge low-pressure oil through the valve distribution mechanism. This cycle, hydraulic motor continuous work, output torque and speed. Change the direction of oil in and out of the motor, the rotation direction of the motor output shaft will also change. This kind of motor has the advantages of simple structure, small size, light weight, wide range of output speed and torque, and higher efficiency than involute gear motor. But the output shaft will inevitably bear the radial force in the work. The radial force makes the matching surface of the valve distribution part and the shell eccentric and worn, which will reduce the volumetric efficiency. At the same time, the transmission error will also affect the distribution accuracy. Ymc-40 cycloid motor is such a structure.
Figure L shows the valve sleeve structure of the cycloid hydraulic motor with valve sleeve. The output shaft drives the valve sleeve to rotate through the transmission pin. The valve sleeve floats on the output shaft and is not affected by the radial force, so that the matching surface of the valve sleeve and the shell can be concentric, so the service life can be prolonged. But the longer the transmission chain, the lower the distribution accuracy.
② The end face distribution of cycloid motor with end face distribution is the distribution of distribution plate, and its distribution accuracy is easy to guarantee. There are two kinds of end face flow distribution: the end face flow distribution with gap compensation and the end face flow distribution with fixed gap.
Figure m shows a cycloid motor with a port plate port whose clearance can be compensated. Figures s to o show the structure of the auxiliary valve plate, valve plate and compensation plate in the motor. When the motor is filled with pressure oil, the rotor 12 rotates and rotates in the stator 9. On the one hand, the rotation movement is transmitted to the output shaft 1 through the long spline coupling 2, and on the other hand, the port plate 4 is driven to rotate through the short spline coupling 7. The setting principle of the port holes on the port plate 4, the compensation plate 6 and the auxiliary port plate 3 is the same as that of the port shaft in the cycloid motor, the port holes in the case and the port holes in the auxiliary port plate shown in Fig. K. Because of this continuous flow distribution, the rotor and output shaft of the motor can rotate continuously. Due to the current reasonable compression coefficient between the compensation plate and the valve plate, and between the valve plate and the auxiliary valve plate, the compensation plate will automatically move to the left after the motor works for a period of time to compensate the wear between the compensation plate and the valve plate, and between the valve plate and the auxiliary valve plate, so as to maintain a high volumetric efficiency.
If the compensation plate and the elastic compensation ring in the cycloid motor shown in Fig. m are cancelled, there is a small gap between the right end face of the valve plate and the rear housing, that is, the end face valve cycloid motor with a fixed gap. This kind of motor has the advantages of simple structure and small axial size, but it can not automatically compensate after the valve plate is worn, so the pressure of this kind of motor is not too high and the output torque is not big.
③ The cycloid motor valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve valve. The flow distribution accuracy of the slide valve is high, which can greatly improve the phenomenon of trapped oil. The motor with this distribution mode has high mechanical efficiency and low noise. The working pressure is high, but the structure is complex, so the filtering accuracy of the oil filter is high.
④ Cycloidal motor with integral stator and cycloidal motor with assembled stator most of the stators of cycloidal motors are integral. As shown in Figure K and figure m, the stators of motors are integral. The geometric dimension accuracy of this kind of stators depends on the accuracy of machining tools and the control of heat treatment deformation.
The stator of cycloid motor with assembled stator is shown in Fig. Q. it uses roller to replace the arc tooth shape of inner tooth ring, and the roller can rotate freely in the stator. When working, the roller located at the junction of the high and low pressure cavities is pressed to the low pressure direction by the oil pressure, which makes the roller close to the stator and rotor and reduces the leakage. And the roller rotates with the rotor, and the two teeth are in rolling contact, so the wear of the two gears is very small. The cycloid motor has the advantages of high efficiency, long service life, high working pressure, uncomplicated stator technology and easy to guarantee geometric accuracy.