Solving practical problems in cone crusher design, the quantity of rock material failing out of the crushing chamber during one eccentric rotation of the cone was analyzed. A simple and practical model for predicting cone crusher output is proposed. Based on previous research a model able to directly calculate the mass percentage of flakiness in the product has been obtained and a method of analysing the variation of the flakiness percentage in the process of crushing is proposed. Taking the output prediction model as an objective function, and the size reduction model and flakiness prediction model as constraints, optimization of the cone crusher has been achieved. The validity of this optimization was verified via full-scale testing. This work will prove useful for developing further cone crusher improvement strategies. (C) 2009 Elsevier Ltd. All rights reserved.