As the power source and actuator of the hydraulic system, the performance of the hydraulic motor has a great impact on the performance of the entire hydraulic system. Therefore, the importance of studying the hydraulic motor performance test system is special-purpose Cycloidal motor of overhead crane It is very important that the rise and application of hydraulic testing technology based on virtual instrument has opened up a broad prospect for the performance testing of hydraulic motors. Hydraulic motors are widely used in machine tools, metallurgy, engineering machinery, plastic machinery, agricultural machinery, mining machinery, marine machinery and many other important fields. The performance of the hydraulic motor has a decisive impact on the whole system, and will directly affect the stability of the system. At the same time, the performance of the hydraulic motor will have an impact on the life of the system components and the production efficiency of the system. Zhuhai manufactor Unexpected failure of hydraulic motor will greatly reduce production efficiency.
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.
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 Cycloidal motor of overhead crane 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 Cycloidal motor of overhead crane 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.
Generally, rolling bearing or hydrostatic sliding bearing, hydraulic special-purpose Cycloidal motor of overhead crane Since the pressure motor works under the condition of input pressure oil, it does not need to have self-priming capacity, but it needs to have a certain initial air tightness to provide the necessary starting torque. The existence of these differences makes the structure of the hydraulic motor and the hydraulic pump relatively close, but they cannot work reversibly. The classification of hydraulic motors can be divided into gear type, impeller type, plunger type and other types according to the structure type. According to the rated speed of the hydraulic motor, it can be divided into high speed and low speed. The rated speed exceeds 500r/min Zhuhai Cycloidal motor of overhead crane High speed hydraulic motor, while the rated speed is lower than 500r/min, it belongs to low speed hydraulic motor.
With the rapid development of China's economy, since the reform and opening up, the machinery industry has improved the advanced productivity in China by constantly introducing foreign technology. Especially after China's accession to the WTO, the machinery industry has accelerated scientific and technological innovation, and the annual export of equipment has continued to grow. With the continuous technological innovation of the hydraulic press industry in China, a number of high-tech industrial companies have emerged, and there are thousands of domestic production enterprises with a certain scale. Hydraulic press products are commonly used in stamping processing and stamping forming processes, such as forging, stamping, cold extrusion, straightening, bending, flanging, plate stretching, powder metallurgy, press fitting, etc. They are metal, plastic, rubber, wood, powder and other products. It can not only meet the functional diversification of electromechanical products to the maximum extent, but also is the basic guarantee for completing major projects and major technological transformation. Now the hydraulic press products have been widely used in automobile, engineering machinery, agricultural machinery, machine tools, plastic machinery, metallurgy and mining, power generation equipment, railway, ship, light industry, electronics, and defense industry products.
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 Cycloidal motor of overhead crane 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 Zhuhai 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.