LIMING type jaw crusher, primary crushers in the mineral industry; attains maximum amplitude at the bottom of the crushing jaws as the swinging jaw is hinged at the top of the frame. These crushers are operated by and controlled by a pitman and a toggle. The feed opening is called gape and opening at the discharge end termed as the set. The Blake crushers may have single or double toggles. The toggle is used to guide the moving jaw. The retrieving motion of the jaw from its furthest end of travel is by springs for small crushers or by a pitman for larger crushers. During the reciprocating action, when the swinging jaw moves away from the fixed jaw the broken rock particles slip down and are again caught at the next movement of the pitman and are crushed again to even smaller size. This process continued till the particle sizes becomes smaller than set; the smallest opening at the bottom. For a smooth movement of the moving jaws, heavy flywheels are used.
Dodge Type Jaw Crusher
The movable jaw is pivoted at the bottom and connected to an eccentric shaft. The universal crushers are pivoted in the middle so that the jaw can swing at the top and the bottom as well. Maximum amplitude of motion is obtained at the top of the crushing plates. Dodge type crushers are not used for heavy duty and commonly found in laboratories.