David Masinde Munyasi

Analysis of the single toggle jaw crusher kinematics

Purpose – This paper aims to obtain equations that can be used to describe the motion of any given point in the swing jaw of a single toggle jaw crusher. Design/methodology/approach – The swing jaw drive mechanism of a single toggle jaw crusher is modelled as a planar crank and rocker mechanism with the swing jaw as the coupler link. Starting with the vector loop closure equation for the mechanism, equations of the position, velocity and acceleration of any given point in the swing jaw are obtained. Findings – Application of the kinematical equations that were obtained is demonstrated using the dimensional data of a practical single toggle jaw crusher. Thus, a description of the kinematics of any given point in the swing jaw of a single toggle jaw crusher is realized. Originality/value – The model of the single toggle jaw crusher mechanism as a planar crank and rocker mechanism is a realistic one. The equations obtained in this paper should be useful in further studies on the mechanics and design of the s...

The kinematics and mechanical advantage of the double-toggle jaw crusher:

The purpose of this article is to obtain a comprehensive mathematical description of the kinematics of a double-toggle jaw crusher. The driving mechanism of the crusher is modeled as a planar six bar linkage. Two closed position vector loops that characterize the configuration of the mechanism are used to derive expressions for the angular position, velocity and acceleration of the moveable jaw. Dimensional data of a typical double-toggle jaw crusher are used in the derived mathematical expressions to demonstrate their application. Moreover, starting with the equation for the angular velocity ratio of the moveable jaw, with respect to the input crank, an expression for the ideal mechanical advantage of the crusher is derived. The expressions derived in this paper provide the foundation for further investigations into the mechanics and the design of the double-toggle jaw crusher.

Analysis of the Single Toggle Jaw Crusher Force Transmission Characteristics

This paper sets out to perform a static force analysis of the single toggle jaw crusher mechanism and to obtain the force transmission characteristics of the mechanism. In order to obtain force transmission metrics that are characteristic of the structure of the mechanism, such influences as friction, dead weight, and inertia are considered to be extraneous and neglected. Equations are obtained by considering the balance of forces at the moving joints and appropriately relating these to the input torque and the output torque. A mechanical advantage, the corresponding transmitted torque, and the variations thereof, during the cycle of motion of the mechanism, are obtained. The mechanical advantage that characterizes the mechanism is calculated as the mean value over the active crushing stroke of the mechanism. The force transmission characteristics can be used as criteria for the comparison of different jaw crusher mechanism designs in order to select the most suitable design for a given application. The equations obtained can also be used in estimating the forces sustained by the components of the mechanism.