In the middle opening system, the main reversing valve of the middle opening system is in the middle position, through which the hydraulic pump is unloaded, and the liquid returns to the oil tank under low pressure. This kind of system generally uses constant displacement pump as oil source; When the reversing valve is in the middle position, the energy transmission starts with a low value that is basically zero, and the energy rises after changing, so that the pressure liquid enters special-purpose High speed high torque cycloidal hydraulic motor The actuator acts on the load; When the reversing valve is in the middle position, the internal leakage is very small. Generally, when the same function is achieved, the energy consumption of the intermediate open circuit is smaller. in Wuxi special-purpose Open system is mostly used for working conditions requiring intermittent movement or supporting load, such as prime movers that do not want to start and stop frequently. The system has high efficiency, and needs to use makeup oil pump and flushing valve for oil makeup and heat exchange.

1) Select the hydraulic pump or motor with good quality and conduct regular maintenance. For example, if the tooth profile accuracy of the gear is low, grind the gear to meet the requirements of the contact surface; 2) If the vane pump has trapped oil, the triangular groove of the oil distributor should be corrected to remove the trapped oil; 3) If the axial clearance of the hydraulic pump is too large and the oil delivery is insufficient High speed high torque cycloidal hydraulic motor manufactor Repair to keep the axial clearance within the allowable range; 4) If the hydraulic pump is not selected correctly, it should be replaced immediately. 3. The reversing valve is improperly adjusted. Improper adjustment of the reversing valve causes the valve core of the reversing valve to move too fast, resulting in reversing shock, noise and vibration. During operation, the valve core branch of hydraulic valve Wuxi High speed high torque cycloidal hydraulic motor Support on the spring. When its frequency is close to the pulsating frequency of oil delivery rate of hydraulic pump or other vibration sources, vibration and noise will be generated.

After disassembling and inspecting the hydraulic motor installed on the drill, it was found that the friction surface of the valve disc and the port plate of the hydraulic motor was severely worn, and the deepest worn part was 0. 15mm; The output shaft oil seal is leaking. Cause analysis of oil leakage of output shaft oil seal. After disassembly inspection and test, the axial and radial clearances of the output shaft meet the standard requirements special-purpose High speed high torque cycloidal hydraulic motor There is no obvious wear on the oil seal mating surface. However, it is found that the oil seal rubber has hardened and its elasticity has deteriorated. With the increase of sealing lip wear, the pre tightening capacity and sealing performance decrease, and the excessive oil temperature accelerates the wear of sealing lip; In addition, due to the liquid Wuxi High speed high torque cycloidal hydraulic motor The leakage of the pressure motor causes the back pressure in the housing to be too high, which further aggravates the wear and leakage of the sealing lip. The smaller the friction of the rotor in the stator sleeve, the higher the mechanical efficiency of the motor.

What is the oil supply mode of the hydraulic pump? The straight shaft swashplate plunger pump can be divided into two types: self suction type and pressurized type. Most high-pressure oil supply hydraulic pumps use pneumatic oil tank, and some hydraulic pumps are also equipped with oil make-up slave pump to deliver pressure oil to the oil inlet of the hydraulic pump. The self-priming pump has the characteristics of strong self-priming ability and no need for external oil supply special-purpose High speed high torque cycloidal hydraulic motor 。 Bearings for hydraulic pumps. The most important part of the plunger pump is the bearing. If the bearing has clearance, the normal clearance of the three pairs of friction pairs inside the hydraulic pump cannot be guaranteed. At the same time, the hydrostatic support oil film thickness of each friction pair will be damaged, thus reducing the service life of the plunger pump bearing. According to the data provided by the manufacturer of the hydraulic pump, the average service life of the bearing is 10000 hours. If the service life exceeds this value, a new port shall be replaced. 3、 Conclusion. The service life of the piston pump is related to the maintenance at ordinary times, the quantity and quality of the hydraulic oil, and the cleanliness of the oil. At the same time, avoid High speed high torque cycloidal hydraulic motor manufactor The particles in the oil will wear the friction pair of the plunger pump, which is also an effective method to extend its service life.

The valve control system controls the flow by changing the opening of the valve throttle, thus controlling the speed of the actuator. Usually, the reason for low efficiency is the existence of throttling and overflow losses. Almost all mechanical equipment adopts valve control system. The pump control system can realize the stepless control of speed by changing the displacement of variable displacement pump, or control the flow through the combination of multiple constant displacement pumps to achieve the stepwise control of speed. The reason for high efficiency is that there is no throttling or overflow loss. It is widely used in high power hydraulic devices such as pressure processing machinery and plastic machinery. The actuator control system controls the flow by changing the variable hydraulic motor flow of the actuator, or through the joint work of multiple quantitative hydraulic motors, or by changing the action area of the composite hydraulic cylinder. Similar to the pump control system, this system has high efficiency because it has no throttling and overflow losses. It is suitable for traveling machinery, press and other hydraulic equipment.

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 High speed high torque 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 High speed high torque 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.