At this stage, road sweepers, trenchless drilling rigs and airport luggage carts are all equipped with several orbit motor System used in series. The motor output shaft often leaks oil in use. Even if the dynamic seal of the output shaft is replaced, it will not help. In fact, the problem of casing oil leakage pressure is ignored in the selection of cycloidal motor and series application.

The case oil drainage pressure means that the motor shaft seal can withstand a large pressure after being well lubricated in the motor; If the motor is used improperly, the oil in the housing will not be released due to various factors after the machine runs continuously for a period of time, and finally the housing pressure of the motor will be higher, causing the shaft seal to be invalid first. The case oil discharge pressure mentioned here is not the bursting pressure of the case, but the pressure that the dynamic seal of the motor output shaft can bear. In some manufacturers' motor samples, only the back pressure is mentioned. In fact, the back pressure refers to the return oil pressure of the motor, not the case oil discharge pressure. During operation, the requirements for the case oil discharge pressure of cycloidal motor are as follows: Eaton is the earliest manufacturer of cycloidal motor in the world. In China's domestic cycloidal motor manufacturing industry, Eaton Fluid Power (Jining) Co., Ltd. adopts American Eaton technology to produce cycloidal motors. The dynamic seal of its output shaft has a much better pressure bearing capacity, that is, through the unique internal oil channel design of its products, the internal oil leakage can also play a role in lubricating parts, It can also drain the excess oil while maintaining a certain oil drain pressure of the housing. Generally, the case oil drainage pressure of domestic axial flow distribution motors is below, that of disc flow distribution motors is below, while that of the axial flow distribution motors produced by Eaton Fluid Power (Jining) Co., Ltd. is, and that of disc flow distribution motors is. These information are clearly explained in the company's motor samples. It should be noted that when the oil drain (internal drain) pressure of the motor housing is higher than its recommended value, the external drain port of the motor housing needs to be connected to the oil tank, otherwise it will greatly affect the life of the motor shaft seal, or even make the shaft seal invalid, resulting in oil leakage at the output shaft.

In actual work, it is not recommended that motors should be used in series. On the contrary, in order to ensure the synchronization of multiple actuators, and to scientifically control costs on the premise of ensuring design quality, the cycloidal motor produced by Eaton has greatly optimized the pressure bearing capacity of the housing. For example, the housing oil discharge pressure of ht series axial flow distribution motors reaches, The casing oil discharge pressure of the 2000 series disc flow distribution motor is up to, which effectively enhances the ability of the motor to be used in series, provides an improvement plan for the design of the machine, reduces the flow of the pump source, and saves the manufacturing cost.