What is the principle of CNC shearing machine?

In the current wave of intelligent manufacturing, numerical control technology is like a powerful driving force, pushing various mechanical equipment towards high precision, high efficiency, and automation. As a capable "leader" in the field of metal sheet processing, CNC shearing machines play a key role in many industries with their excellent performance and precise cutting ability. So, what principle endows CNC shearing machines with such powerful functions? Let's unveil its mysterious veil together.

1. Numerical Control System: The Core of Precise Control

The numerical control system (CNC) of a CNC shearing machine is the "brain" of the equipment, consisting of hardware (controller, servo drive, input/output module) and software (programming system, motion control algorithm). Its core function is to control cutting parameters through preset programs, including cutting length, angle, speed, and cutting times.

The operator inputs parameters such as sheet thickness, material, and cutting size through the human-machine interface (HMI), and the CNC system converts the parameters into digital signals and transmits them to the servo drive. The servo driver controls the speed and direction of the motor (such as an AC servo motor) based on the signal, and then drives the transmission mechanism to achieve precise positioning of the shearing action. For example, the system can control the positioning error within ± 0.1mm through closed-loop control (encoder feedback) to ensure cutting accuracy.

2. Transmission Execution: Transmission of Power and Motion

The transmission system of the CNC shearing machine consists of two parts: mechanical transmission and hydraulic transmission, responsible for converting the instructions of the CNC system into actual actions.
1. Mechanical transmission: Using ball screw or gear rack transmission, the rotational motion of the servo motor is converted into linear motion, driving the upper tool holder to move vertically along the guide rail. Ball screws have the characteristics of high precision and low friction, and can achieve micrometer level displacement control.

2. Hydraulic transmission: The hydraulic system provides the power required for shearing, converts mechanical energy into hydraulic energy through a hydraulic pump, and drives a hydraulic cylinder to quickly lower the upper tool holder. The hydraulic system is equipped with proportional valves or servo valves, which can adjust pressure and flow according to numerical control instructions to achieve precise control of shear force. For example, the system can automatically adjust the hydraulic pressure based on the thickness of the sheet to avoid overload or insufficient shear.

3. Cutting action: precise separation of sheet metal

The cutting action is the core function of the CNC shearing machine, which is completed by the cooperation of the upper blade holder, lower blade holder, and rear material blocking device.
1. Upper knife holder: Under the drive of the hydraulic cylinder, it is vertically pressed down and matched with the blade fixed on the lower knife holder to complete the cutting of the sheet metal. The blade material is usually high-strength alloy steel, and after heat treatment, its hardness can reach HRC58-62, ensuring the wear resistance of the cutting edge.
2. Rear material blocking device: Driven by a servo motor, the blocking position is adjusted according to CNC instructions to control the cutting length of the sheet metal. The rear material blocking device is equipped with linear guide rails and encoders, which can achieve millimeter level positioning accuracy.
3. Cutting process: The board is placed on the workbench, and after the rear blocking device is positioned, the upper knife holder quickly presses down, and the blade cuts into the board to complete the cutting. After the cutting is completed, the upper knife holder rises and the rear material blocking device is adjusted to the next cutting position, achieving continuous automated operation.
With the continuous advancement of technology, the principle of CNC shearing machines will also be continuously optimized and improved. In the future, we have reason to believe that CNC cutting machines will have a higher level of intelligence, capable of achieving more complex cutting tasks while further improving cutting accuracy and production efficiency. It will be widely applied in more industries and play a more important role in promoting the upgrading and development of the manufacturing industry.