At present, the system used in series by multiple cycloidal motors (see Figure 1) is applied to sweepers, trenchless drills and airport luggage carts. The output shaft of the hydraulic motor often leaks oil during use, so it is useless to replace the dynamic seal of the output shaft. In series application, the problem of casing oil leakage pressure is ignored. The oil leakage pressure of the housing refers to the maximum pressure that the motor shaft seal can bear after the hydraulic motor is fully lubricated inside; If the hydraulic motor is applied special-purpose Low speed cycloidal hydraulic motor Improper. After the machine has been working continuously for a period of time, due to various factors, the oil in the housing will not be released, resulting in higher and higher pressure in the housing of the hydraulic motor, which first leads to the failure of the shaft seal. The casing leakage pressure mentioned here is not the bursting pressure of the casing, but the pressure that the motor output shaft dynamic seal can bear. In the motor samples of some manufacturers, only the back pressure is mentioned. Actually, back pressure refers to electricity Low speed cycloidal hydraulic motor manufactor The return oil pressure of the engine, not the oil discharge pressure of the casing. During operation, the requirements for the oil discharge pressure of the cycloidal motor housing are as follows. Eaton is the world's first cycloid motor manufacturer. In China's domestic cycloidal motor manufacturing industry, Jining Jinjia Hydraulic Co., Ltd. uses Eaton technology to produce cycloidal motors. Its output shaft dynamic seal has better bearing capacity, that is, the unique internal oil circuit design of the company's products enables internal oil drainage not only to lubricate parts, but also to discharge excess oil while maintaining a certain housing oil drainage pressure.
The output pressure of the hydraulic motor also depends on the load. Rated pressure Pn: the rated pressure refers to the working pressure that the hydraulic motor can withstand during continuous operation. It can special-purpose Low speed cycloidal hydraulic motor To ensure the volumetric efficiency and service life of the hydraulic motor. Working pressure P: the working pressure is the actual pressure of oil input when the hydraulic motor is working Low speed cycloidal hydraulic motor manufactor power. Its value depends on the size of the load. However, the maximum working pressure is determined by the safety valve in the hydraulic system. The throttle adjustment value must not exceed the maximum pressure value of the hydraulic motor. The third is the maximum pressure: the limit pressure that the motor is allowed to overload in a short time. Pn ≤ Pmax value.
When the working load changes from low speed to high speed in a wide range, the hydraulic motor is also required to be able to drive and regulate speed in the corresponding wide range, which requires the motor to have good low-speed stability and high speed performance. The speed regulation range K of the hydraulic motor is usually expressed by the ratio of the allowable maximum speed to the minimum speed. special-purpose Low speed cycloidal hydraulic motor It is the highest operating speed of hydraulic motor, but it is limited by many factors, mainly including: 1. Service life. After the speed increases, each pair is worn Xingtai manufactor The service life is shortened. 2、 Mechanical efficiency limits. At high speed, the hydraulic motor needs to input large flow, accordingly, the hydraulic loss of each circulating component increases, reducing the mechanical efficiency.
The weight per unit of electricity is very light. Statistics show that the weight of hydraulic pump and hydraulic motor per unit power is only the generator. 1/10 of the motor, hydraulic pump and hydraulic motor can be as small as 0.0025N/W, and the generator and motor with the same power can be about 0.03N/W. As for size, the former is about 12%~13% of the latter. In terms of output force, it is easy to get extremely high pressure hydraulic fluid with a pump, which will produce great force after being delivered to the hydraulic cylinder. Therefore, hydraulic technology has the advantages of light weight Xingtai manufactor The outstanding characteristics of small size and large output are conducive to the miniaturization and miniaturization of mechanical equipment and its control system for high-power operation. Flexible and convenient layout. The configuration of hydraulic components is not restricted by the strict space position, and it is easy to pass according to the needs of the machine. The connection of all parts of the system is realized through pipes, and the layout setting has great flexibility special-purpose Low speed cycloidal hydraulic motor Soft, which can form a complex system that is difficult to form by other methods.
Cycloidal hydraulic motor structure: the internal meshing gear pair consisting of rotor and stator, cycloidal needle wheel, as the meshing pair, has a torque generating part. The stator, together with the spacer and the rear cover, is fixed on the housing to form seven cavities that are only connected with the oil holes on the housing one by one. A distribution mechanism consisting of an oil distribution sleeve and a housing. Two oil distribution sleeves Xingtai Low speed cycloidal hydraulic motor The ring groove is respectively connected with the oil inlet and return ports of the housing, and its longitudinal groove has twelve oil ports, Low speed cycloidal hydraulic motor manufactor Six oil ports and the oil distribution hole of the housing form the oil distribution link. The splines at both ends of the linkage shaft are respectively connected with the rotor and the output shaft, which is used to transmit torque and ensure that the oil sleeve is synchronized with the output shaft. The function of the output shaft is to output the torque generated by the rotor through the linkage shaft and drive the oil distribution device to rotate synchronously.