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 customized Micro cycloid 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 Micro cycloid 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 hydraulic motor manufacturer explains to you the reasons for the poor performance of the hydraulic motor: 1. First of all, according to the analysis of the causes of the wear of the port plate, the main reasons for the weakness of the hydraulic motor are: because the port plate is worn, the oil inlet channel and the oil return channel are connected at the port plate, part of the high-pressure oil leaks, the oil pressure flowing through the stator and rotor pair decreases, and the flow decreases, Eventually, the output speed and torque of the motor will decrease. 2. Due to the wear of the valve plate, its relative position in the valve body has changed Micro cycloid motor manufactor The preload and adhesion of the spring on the valve body between the valve plates will be reduced, which will intensify the leakage of hydraulic oil and lead to the decline of the performance of the hydraulic motor. 3. With the increase of hydraulic oil temperature, its comprehensive performance declines, driving the cycloidal rotor to rotate Zhangjiakou manufactor The ability to move is further reduced. Upon inspection, there is no obvious wear on the joint surface of the stator and rotor pair and the bearing seat and valve disc matched with both sides of the stator and rotor pair. The movement is normal without jamming, which will not cause performance degradation.
The ignition time of internal combustion engines can be compared with this. It can be seen from the working principle of the cycloidal hydraulic motor that the oil sleeve and the rotor rotate synchronously, and the accuracy refers to the accuracy of the oil distribution link matching with the rotor to rotate the oil inlet, seal and discharge. There are many factors customized Micro cycloid motor It will affect the oil distribution accuracy, such as the asymmetry of the rotor spline and cycloid tooth shape, the relative position accuracy of the stator sleeve needle hole and bolt hole, and the relative position asymmetry of the pin hole and spline on the output shaft and its internal spline, Micro cycloid motor manufactor The relative position accuracy of the longitudinal oil groove and the relative wedge groove of the coupling, and the asymmetry of splines at both ends of the coupling. As long as the above factors are controlled within the tolerance range, they will not have a great impact on the oil distribution accuracy, because all processing errors will not be offset.
The hydraulic motor has two circuits: the hydraulic motor series circuit and the hydraulic motor braking circuit. These two circuits can be classified into the next category. One of the series circuits of hydraulic motors: three hydraulic motors are connected in series with each other, and a reversing valve is used to control the start stop and steering. The flow through the three motors is basically the same. When the displacement is the same, the speed of each motor is basically the same. The oil supply pressure of the hydraulic pump Zhangjiakou manufactor High, small pump flow, generally used for light load and high speed. Serial circuit II of hydraulic motor: each reversing valve in this circuit controls one motor, each motor can work independently or simultaneously, and the rotation direction of each motor is also customized Micro cycloid motor optional. The oil supply pressure of the hydraulic pump is the sum of the working pressure difference of each motor, which is applicable to the condition of high speed and small torque.
1. The hydraulic system is characterized by high energy density. For motors with the same power, hydraulic motors are much smaller and lighter than motors. And it is easy to apply to mobile devices. 2. The hydraulic motor has convenient speed regulation, which can be adjusted infinitely from 0 to the maximum speed according to the adjustment of the hydraulic valve. The motor itself does not need special design and has low cost. This is much cheaper than motor+reducer, or variable frequency motor and servo motor. 3. The hydraulic motor is totally enclosed and can be safely used in dusty, wet (even underwater) and flammable environments, which is much more reliable than explosion-proof (flameproof) motors. 4. The hydraulic system has strong anti overload capacity, and it is protected by the overflow valve, allowing long (relatively) frequent overloads. It is easy to recover under overload conditions, without damaging the equipment or restarting the equipment. These unparalleled advantages of motors have made hydraulic motors and hydraulic technology rapidly spread and popularized all over the world in the past 20 years. People increasingly feel the importance of hydraulic motors in practice.