CNC sheet metal bending machine generally adopts all-steel welded structure, with sufficient strength and stiffness. Hydraulic transmission, both ends of the oil cylinder installed on the slider, directly drive the sliding work. The slider synchronization mechanism adopts torsion shaft to force synchronization. Adopt mechanical block structure, stable and reliable. Slide stroke can be quickly manually adjusted, counter display. Oblique wedge deflection compensation mechanism to ensure high bending accuracy. The three common structural types of sheet metal flexors are as follows:
1. Upward movement, that is, the slider drives the punch down. In order to ensure that the slider will not be due to the unbalanced load of the slider and the difference between the left and right cylinder pipe resistance and relative tilt, thus affecting the forming quality of the workpiece, usually equipped with the slider movement synchronization control system. The up-moving type is easily equipped with mechanical or hydraulic synchronous control system. The mechanical synchronization device is simple in structure, low in cost, and can obtain a certain synchronization accuracy, but the ability to bear eccentric load is poor, so it is only suitable for small and medium-sized hydraulic sheet metal bending machine. Hydraulic synchronization coefficient includes mechanical hydraulic servo synchronization system, electro-hydraulic servo synchronization system and numerical control synchronization system. This kind of synchronous system has high precision and is suitable for sheet metal bending machine which requires high bending accuracy. But the technology is complicated and the cost is high.
2. Sliding type, that is, the slider is installed at the lower part of the machine tool, driving the concave die to move up. The working oil cylinder is placed in the center of the slide block. When the nominal force is small, it is a single oil cylinder. When the nominal force is large, it is a three oil cylinder. Because the working cylinder is concentrated in the middle of the slider, the deformation of the slider and the beam is consistent, and the gap between the concave and convex die is uniform over the whole length of the slider, so the bending accuracy of the workpiece is high. The slider returns by its own weight, and the hydraulic system is simple. The advantages of the sliding type are light weight, compact structure and easy maintenance; The disadvantage is that the synchronization accuracy is not high; Single cylinder is difficult to solve the problem of slider tilt; The depth at which the punch enters the die is difficult to precisely control. Not suitable for drilling; And the die on the work table moves upward with the workpiece, the operator is not easy to operate.
3. The CNC bending machine works according to the working origin of the above three-point bending method. The three-point bending machine has the advantages of high bending precision, wide application of technology and function of four-sided molding machine. But the structure of machine tools is complex and the cost is high.
