CNC Press Brake How to Choose Oil System – Open Loop or Closed Loop

The hydraulic control system of CNC Press Brake is composed of hydraulic control and sensor. Hydraulic control and energy conversion usually refer to hydraulic control valves, hydraulic pumps, etc. Hydraulic control technology is an important branch of automatic control system. The hydraulic control system has many obvious features and many advantages and plays an important role in the CNC Press Brake system.

Hydraulic control technology is a typical electro-hydraulic mixing technology. For example, the electric hybrid system is based on the power system and integrates the mechanical system, the electronic system and the hydraulic system. At present, hydraulic control system is widely used in equipment manufacturing, automobile industry, aerospace, metallurgy and other industries.

In this paper, the electro-hydraulic control system of Press Brake is introduced in detail, which can be divided into open-loop control system and closed-loop control system. The beam of the Press Brake is the main control part of the system.

1.Closed-loop system

The closed loop is also called the feedback control system. The system compares the measured value of the output volume of the system with the expected given value, thus generating the deviation signal. The signal deviation is controlled and adjusted by the signal deviation, so that the output value can be close to the expected value. While driving, for instance, the first person in the brain of the car driving direction have a preliminary perception, in the process of driving the car, the man in the car driving direction with eyes to observe and compare the car driving direction and the direction of the desired, constantly in the process to adjust the direction, finally make the car driving direction constantly close to the target direction, forming a closed loop control.

CNC Press Brake

The closed-loop control is based on the operation of various parts of the CNC Press Brake tool, with high precision and reaction speed. Because the closed-loop control system involves many elements, compared with the open-loop system, the whole system is more complex and more expensive.

2.Open-loop system

The open loop is compared to the closed loop, that is, the open loop control does not feedback the current system control results. For example, throwing things, once something is thrown out, people can't control what is thrown out. For as soon as things leave hands, man's control over them ceases.

Therefore, in the open-loop system of the CNC Press Brake, the bending accuracy depends on the precision of each part of the machine tool. The system is unable to control and compensate the parameter change during bending, which leads to low bending precision. Once the outside of the machine tool is disturbed, the internal parameters of the machine tool will change. However, in terms of system design, open-loop design is simpler and more stable. Both the early machine tool installation and the subsequent machine tool maintenance are simpler.

In conclusion, if the buyer has a high demand for bending precision and sufficient purchase capital when purchasing a CNC Press Brake , we suggest you buy a Press Brake with closed loop system. If the bending precision is not high, the Press Brake with open-loop system is OK.

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