The Blake crushers are single or double toggle drives. The function of the toggle(s) is to move the pivoted jaw. The retrieving action of the jaw from its furthest end of travel is by springs for small crushers or by a pitman for larger crushers. As the reciprocating action removes the moving jaw away from the fixed jaw the broken rock particles slip down, but are again caught at the next movement of the swinging jaw and crushed. This process is repeated until the particles sizes are smaller than the smallest opening between the crusher plates at the bottom of the crusher(the closed set). For a smooth reciprocating action of the moving jaws, heavy flywheels are used in both types of crushers.
Fig. 4.1 shows a sketch of a Blake Crusher operated by double toggles and controlled by a pitman. These are commonly used as primary crushers in the mineral industry. The size of the feed opening is referred to as the gape. The opening at the discharge end of the jaws is referred to as the set.
Fig. 4.2 is a sketch of a Dodge type of crusher. They are comparatively lower in capacity than the Blake crushers and are more commonly used in laboratories.
Cement equipment : http://www.china-crusher.com/48.htm
Sand maker :