The hydraulic cutting machine uses hydraulic oil as the working medium. The mechanical energy of the prime mover is changed into the pressure energy of the hydraulic oil through the power component (oil pump), and then the pressure energy is converted by the control element and then by the actuator (cylinder or oil motor). For mechanical energy, the drive load is linear or rotary, and the force and speed of the actuator are set by remote control of the control element and adjustment of the flow. When the outside world is disturbed by the above system, the output of the actuator generally deviates from the original set value, resulting in a certain error.
Hydraulic control of the cutting machine: Like the hydraulic transmission, the system also includes power components, control components and actuators, which also transfer power through the oil. The difference between the two is that the hydraulic control has a feedback device. The function of the feedback device is to feedback the output of the actuator (displacement, velocity, force, etc.) back to the input (which can be varied or constant). In comparison, the resulting deviation is used to control the system so that the output of the actuator changes or remains constant as the input varies. It is a hydraulic transmission system that constitutes a closed loop, also known as a hydraulic servo system or a hydraulic servo system.
The hydraulic cutting system of the hydraulic cutting machine uses an on-off or logic control element. For the purpose of control, it is to maintain the stable or simply changing direction of the set value, also called constant value and sequential control elements.
The hydraulic control system uses servo control components, has a feedback structure, and is controlled by electrical devices. It has high control accuracy and response speed, and the controlled pressure and flow rate often change continuously. The output power can be amplified.
Proportional control is a kind of control between the two. The proportional control valve is a new type of electro-hydraulic control element developed on the basis of on-off control components and servo control components. Some of the features of the components, the on-off control for manual adjustment can not meet the requirements, but also do not require the servo valve to be as strict as the pollution control requirements of the hydraulic system.