Shear crusher and cutter overload protection system thereof

The invention discloses a cutter overload protection system comprising a cutter shaft rotationally arranged on a machine frame, a movable cutter arranged on the circumferential face of the cutter shaft, a cutter holder connected to the machine frame in a turnover mode, a fixed cutter arranged on the cutter holder and meshed with the movable cutter, and a first driving component arranged on the machine frame and connected with the cutter holder. When the pressure between the movable cutter and a fixed cutter is overloaded, the cutter holder is driven to overturn so that the movable cutter and the fixed cutter can be disengaged and a gap can be reserved for foreign matters to pass through. Therefore, according to the cutter overload protection system provided by the invention, when the pressure of the movable cutter and the fixed cutter is overloaded, the fixed cutter is separated from the movable cutter after being overturned along with the cutter holder through the driving effect of the first driving part on