Views: 86 Author: Durmapress Publish Time: 2020-07-20 Origin: Durmapress
Press Brake is a widely used bending machine, which has already been hydraulicized. As an important equipment for sheet metal processing, the sheet metal press brake plays its irreplaceable role and plays a decisive role in the quality, processing efficiency and accuracy of the product.
Generally, the press brake is an upper-piston press, which is composed of a frame, a slider, a hydraulic system, a front pallet, a backstop, a mold, and an electrical system.
Two parallel working hydraulic cylinders form vertical downward pressure to drive the mold on the bending beam to perform the bending work. As the brain of the press brake, the hydraulic control system mainly controls the synchronous operation of the bending process and the positioning of the hydraulic cylinder when the machine is working at full load. I will take a certain type of universal press brake as an example to analyze the hydraulic system.
Metal press brake Hydraulic system:
Figure as follow shows the hydraulic system of the cnc press brake machine. Every time you perform a bending action, the bending cycle of the typical bending process of the beam is moved. include:
(1)The oil pump starts
The motor rotates in the direction marked by the pump arrow, that is, clockwise, driving the axial plunger pump. The oil enters the valve plate and the electromagnetic overflow valve back to the tank through the pipeline. When the 19th valve is closed, the lower chamber of the 20th cylinder The oil keeps the slider at a fixed position.
(2)Downward movement
The rapid downward movement of the cnc press brake for sale generates movement through the weight of the press brake beam and various accessories and the pressure of the oil. In this process, the rod-less cavity of the hydraulic cylinder is fed with oil through the filling valve, and the rod cavity will generate back pressure and the oil will return quickly. The fast-forward movement starts from the top dead center, and after a short period of deceleration, the slider slows down at a certain distance close to the bending plate.
When No. 9 YV1, No. 24 YV6, No. 13 YV4, No. 17 YV5 electromagnets work, the slider quickly descends, the descending speed is adjusted by No. 18 valve, the oil in the lower chamber of No. 20 cylinder passes through No. 19, No. 18, No. 17 No. enters the oil tank, and the oil in the upper chamber of the cylinder 20 is injected through the No. 21 valve.
When the slider descends to the limit switch, No. 9 YV1, No. 8 YV2, No. 11 YV3, No. 13 YV4, No. 24 YV6 electromagnet work, and the slide enters the working speed. If the slider is out of synchronization, it is automatically corrected by the No. 15 valve, and the descending position of the slider is limited by the mechanical stop in the cylinder.
(3)Bending
The bending stage begins with the rodless cavity build pressure. On the one hand, the bending speed is limited by the oil supply of the oil pump, on the other hand, it can be adjusted by the proportional valve directional valve. At the same time, the directional valve also controls the synchronous operation of the bending beam and the positioning of the bottom dead center. Limiting the bending force is accomplished by the prop