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.

Most of its hydraulic system uses working medium, such as hydraulic oil with continuous fluidity, which converts the mechanical energy of the prime mover driving the pump into the pressure energy of the liquid through the hydraulic pump, and sends it to the actuator (hydraulic cylinder, hydraulic motor or swing hydraulic motor) through various control valves, such as pressure, flow, direction, etc., to convert it into mechanical energy to drive the load. This hydraulic system is generally composed of the following parts: power source, actuator, control valve, hydraulic auxiliary device and hydraulic working medium, which play their respective roles: power source: prime mover (motor or internal combustion engine) and hydraulic pump, whose role is to convert the mechanical energy generated by the prime mover into the pressure energy of liquid, and output oil with a certain pressure;

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 customized Crane cycloid 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 Shandong customized 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. Pascal principle: also known as static pressure transmission principle, it refers to the pressure exerted on the static liquid in a closed container is transmitted to all points of the liquid at the same time with equal value. The hyperbolic cosine of 2. The hyperbolic cosine of 2. System pressure: the discharge pressure of the hydraulic pump in the system. The hyperbolic cosine of 3. The hyperbolic cosine of 3. Servo valve and proportional valve: infinitely adjust the output of hydraulic valve, such as pressure, flow and direction, by adjusting the input electrical signal analog quantity. (Servo valve also has pulse customized Crane cycloid motor Wide modulation input mode). But the structure of these two valves is completely different. The servo valve controls the work of the torque motor by adjusting the electrical signal to deflect the armature and drive the front valve to work. The front valve control oil enters the main valve and drives the valve core to work. The proportional valve regulates the electrical signal to make the electric iron shift, drive the pilot valve core, drive the control oil generated, and drive the main valve core. The hyperbolic cosine of 4. The hyperbolic cosine of. Shandong Crane cycloid motor Kinematic viscosity: the ratio of dynamic viscosity μ to the liquid density α. The hyperbolic cosine of 5. The hyperbolic cosine of 5. Fluid power: the force exerted by the flowing liquid on the solid wall to change the flow velocity.

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 Crane 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 Crane cycloid motor Price 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.