Toggle plate is an important spare parts of jaw crusher, It is designed to shear protecting crusher components if non-crushable object is introduced to crusher; Jaw plate's high manganese steel castings can be reversed allowing extended life.
Recently, concern for energy consumption in crushing has led to the consideration of decreasing the weight (and consequently the stiffness) of the toggle plate of jaw crushers to match the strength of the rock being crushed. An investigation of the energy saving of plate rock interaction when point load deformability and failure relationships of the rock are employed to calculate plate stresses. Non simultaneous failure of the rock particles is incorporated into a beam model of the jaw crusher toggle plate to allow stress calculation at various plate positions during one cycle of crushing.
Normally, the stiffness and dimensions of toggle plate are not changed with rock type and all plates are capable of crushing rock such as taconite with an unconfined compressive strength (q) of up to 308 MPa. Only the facing of the swing plate is changed with rock type, to account for changes in abrasiveness or particle shape. For instance, ridged plates are employed with prismatic particles both to stabilize the particles and to ensure the point- loading conditions. Communications with manufacturers of jaw crushers have revealed that no consideration is currently given to force displacement characteristics of the crushed rocks in the design of toggle plate.
As a rock tumbles into position it will catch on a comer of a larger diameter and thus will be loaded at two 'points' of contact. Throughout the paper, 'point' describes contact over a small and limited region of the circumference of the particle. Should flat-sided contact occur, the ribbed face plates of most crushers will apply point loads to the particle. The particle will then fail either by two or three point loading. Thus, any design based upon both deformation and strength must begin with a point-load idealization.