In order to eliminate the adverse effects caused by the deformation of the ram, it is necessary to compensate the deflection deformation of the ram.
Through compensation, the deformation of the sliding block of the press brake is offset, so as to ensure the accuracy of the machining joint surface and improve the accuracy of the workpiece.
Compensation mode of hydraulic cylinder: #
Electro hydraulic servo press brake machine + hydraulic deflection compensation ↓
Hydraulic automatic deflection compensation mechanism of worktable.
It is composed of a group of oil cylinders installed in the lower workbench. The position and size of each compensation cylinder are designed according to the deflection compensation curve of finite element analysis of sliding block and workbench.
Hydraulic compensation realizes the bulge compensation through the relative displacement between the front, middle and rear vertical plates.
The principle is that the bulge is realized through the elastic deformation of the steel plate itself, so the compensation can be adjusted within the elastic range of the worktable.
Mechanical compensation worktable mode: #
Dual electric servo hybrid press brake + mechanical deflection compensation ↓
The convex wedge block is composed of a group of convex wedge blocks with inclined plane.
Each convex wedge is designed according to the deflection curve of finite element analysis of sliding block and worktable.
The numerical control system calculates the required compensation amount according to the bending force when the workpiece is bent (this force will cause the deflection deformation of the sliding block and the vertical plate of the worktable), and automatically controls the relative movement of the convex wedge, so as to effectively compensate the deflection deformation of the sliding block and the vertical plate of the worktable, and an ideal bending workpiece can be obtained
Mechanical deflection compensation realizes “pre bulge” by controlling the position.
A group of wedges form a curve consistent with the actual deflection in the length direction of the workbench, so that the gap between the upper and lower molds is consistent during bending, so as to ensure that the angle of the bent workpiece in the length direction is consistent.
Advantages of mechanical compensation: #
1. Mechanical compensation can obtain accurate deflection compensation over the full length of the workbench.
The use stability of mechanical deflection compensation is long-lasting, the maintenance frequency of hydraulic compensation (such as oil leakage) is reduced, and maintenance is free within the service life of the press brake.
2. Because there are many compensation points for mechanical deflection compensation, the bending machine can bend the workpiece in a linear compensation mode and improve the bending effect of the workpiece.
3. Mechanical compensation uses a potential ruler to measure the return signal position. As a numerical control axis, it realizes digital control and makes the compensation value more accurate.