during normal operation the paper shredder plate will cut off the power supply if there are any non expected items fed in or that accidentally fall into the opening as they will cause a noticeable force that enables the safe power supply switch 12 to cut off power supply u2014 this is the second level protection the touch structure and the safe power supply switch 12 are integrated into one circuit disconnection device that serves as a protection system which actively cuts off the power supply whenever a non expected item is fed in and which functions reversely as a passive conducting device while feeding paper through the paper feed opening the safe power supply switch 12 is a preferential disconnection device different from a safe switch or a paper full switch whose function is realized by adopting a flip flop in a circuit of a paper shredder the safe power supply switch 12 has first level priority to protect a user the paper shredder upper cover 1 and the paper shredder plate 2 refer to any separate or integrated structures able to seal the paper feed opening the paper shredder plate 2 and the paper shredder upper cover 1 are connected such that the former can move separately relative to the latter the touch structure is a cam 21 disposed on the paper shredder plate 2 corresponding to the cam 21 the safe power supply switch 12 is disposed on a corresponding position of the paper shredder upper cover 1 the cam 21 and the safe power supply switch 12 are configured to interact with each other that is when the paper shredder plate 2 is opened the cam 21.