Magnetic Gripper Pneumatic Piston Selective Sheet Lifting

The magnetic gripper employs a dynamic magnetic field strength that changes during the processing cycle. The permanent magnet is positioned close to the workpiece during bending to provide strong holding force, then moved away during lifting to reduce magnetic field strength and prevent multiple sheets from being lifted. This dynamic adjustment resolves the contradiction between needing strong holding force and avoiding lifting multiple sheets.

The magnetic field is activated periodically - strong during the bending operation and reduced or deactivated during the lifting and positioning phases. This periodic activation pattern allows the system to achieve secure holding when needed while avoiding unintended lifting of multiple sheets during other phases of the cycle.

The permanent magnet provides the magnetic field automatically without requiring external power sources, control systems, or complex activation mechanisms. The magnet simply needs to be positioned at the appropriate distance from the workpiece to provide the required holding force, significantly simplifying the gripper design while maintaining reliable holding capability.

The patent replaces complex electromagnetic activation systems with a simple mechanical positioning approach. Instead of using controlled electromagnetic fields requiring power supplies and control electronics, the system uses a permanently magnetized component whose magnetic field strength is controlled by its distance from the workpiece, achieved through simple linear movement of the gripper body.