CNC bending machine is a sheet metal processing equipment that complete the sheet metal bending. With the rapid development of home appliances, electronics, kitchen utensils, instruments, chassis and other industries, customers' product is mostly small size and multi-channel bending sheet parts, as shown in Figure 1. In order to improve work efficiency, purchasing equipment has high requirement on bending speed. While restricted by the space of the factory, small tonnage, the demand information of high speed, excellent performance, and good work accuracy of the bending machine are more and more. For this market segment, in order to compete for more market share and rich product line to meet these industries for small tonnage, high-speed CNC bending machine needs, now we research and develop a high-speed compact CNC bending machine.
Figure 1 small size, multi-channel bending sheet parts map
At present, domestic and foreign CNC bending machine is driven by AC induction motor. Oil pump motor is always working during used.The hydraulic oil is directly returned to the tank by the relief valve in the absence of sheet metal bending. Energy waste is greater. Hydraulic oil heat and oil change cycle is short. The users use the high cost. The high-speed and compact CNC bending machine developed by this project is driven by the servo motor to drive the gear pump. When the upper and lower sheet and the sheet metal are positioned, the servo motor is automatically closed to minimize the no-load power consumption. During the fast down and return, the CNC system achieve high-speed movement through real-time dynamic adjustment of the speed of the servo motor.In the feed and hold stages,when the system pressure reaches the set pressure, the gear pump provides sufficient pressure and flow. The CNC system according to the required speed and pressure give the corresponding speed and torque command to servo motor, so the hydraulic system is no longer resulting in overflow loss and energy-saving effect is obvious. Compared with the traditional hydraulic main drive machine, it saves about 45% energy.