Working Principle and Mechanism Optimization Design of Jaw Crusher

Jaw crusher is mainly used as a primary and intermediate crusher in mining, construction, infrastructure and other industries. According to the width of the feeding mouth, jaw crusher appears as three types, namely, large one with more than 600mm width of feeding mouth, medium-sized one with 300-600 mm width and small one with less than 300 mm width. Jaw crusher has the features of simple structure, easy production, reliable work, convenient use and maintenance.

Working parts of jaw crusher are two pieces of jaw plates; one is fixed jaw plate (fixed jaw) which is vertically (or slightly extroversive on the upper end) fixed on the front wall of the machine, and the other is moveable jaw plate (movable jaw) which is tilted and forms the (big-end up) crushing chamber with the fixed jaw. The movable jaw crusher does periodic and reciprocating motion facing the fixed jaw and moves away from and toward it over and over again. When it moves away, materials go into the crushing cavity, and finished products get out from the bottom; when it moves toward the fixed jaw, materials between the two pieces of jaw plates will be crushed by the forces of impacting, bending and splitting.

According to the different swinging ways of its movable jaw plate, jaw crusher can be divided into three types, namely, simple pendulum type jaw crusher, complex pendulum jaw crusher (compound pendulum jaw crusher) and integrated pendulum jaw crusher.

The technology levels of domestic jaw crusher manufacturers are greatly different. The products of only several manufacturers almost approach world advanced level, while most manufacturers are far from that level. The frame of jaw crusher takes a large proportion of the whole machine (casting frame 50%, welding frame 30%). The frame of foreign jaw crusher is welded and so is the moving jaw. Adopting the welded frame is the development trend of jaw crusher. There are many cases of unreasonable design of frame structure, which results from the failure arrangement of the strengthening ribs according to the actual stress state of jaw crusher.

The essential factor of ensuring the best performance of jaw crusher is to keep the best movement characteristics of movable jaw, which can be realized from mechanism optimization design. Therefore, the optimization design of jaw crusher structure is a fundamental solution to ensure its best performance. By using the optimized design module to optimize all kinds of crushers, the best dynamic movement characteristics can be achieved. Practical results prove that the performance of the crusher has significantly improved. Computer has been very popular in domestic manufacturers, but the mechanism optimization design of jaw crusher has not been widely used. Domestic jaw crusher is generally heavier than foreign crushers with the same specification. Therefore, it is an important subject to reduce the machine weight.