Jaw crusher has two ways to adjust the discharging opening caused by the overload:

First is the hydraulic gyratory crusher that used hydraulic method. The main shaft is installed on the pillar inside the cylinder, through changing the hydraulic oil volume of pillar to change the position of crushing taper, so as to change the size of discharging opening. Under overload condition, the increased pressure of main shaft force the hydraulic oil enter into the accumulator in the hydraulic drive system, making the crushing taper down to increase the discharging opening.

Second is to use the mechanical method. There are adjusting nut on the top of the main shaft, rotating the nut to make the crushing taper up and down, thus adjusting the size of discharging opening accordingly. Under overload condition, to achieve insurance function through cutting the safety pin in the driving pulley.

The up and down movement of jaw crusher can promote the material discharging. Due to the horizontal stroke of upper part is large than that of the bottom part, it is easy to crush the massive materials. 

When the jaw crusher is overload, the taper cover forces the spring compress, so as to increase the discharging opening to discharge the non-crushed materials.