Abstract: An impact crusher is disclosed having a rotor carrying hammers arranged to strike and throw material against target members, and a material feed assembly. The feed assembly includes a downwardly inclined chute having depending cam followers which ride upon a cam surface having a horizontal portion and a downwardly curved portion at the end of the horizontal portion remote from the rotor. An actuating device is connected to the chute to move the chute and cam followers along the cam surface and down the curved portion thereof. Thus when a large rock bridges the space between the feed chute and the target members, and fails to drop into the range of the hammers, the chute is simultaneously retracted away from the rock as the upper end is tilted downwardly toward a horizontal position, to lower or drop the rock into the range of the whirling hammers.

Abstract: A locking means for the impellers of an impact crusher rotor is disclosed wherein the impellers are partly within axially extending peripheral slots which are diametrically opposite each other; semi-cylindrical cavities are formed in the face of the leading wall and the face of the impeller which cooperate to define a cylindrical bore extending parallel to the axis of the rotor; within the cylindrical bore a wedge lock is inserted which is a two-part device each having a flat surface complementary to each other and machined at an angle to the outside diameter of the composite wedge lock; the diameters of the outer surface of each wedge portion is centered at different locations thereby effectively preventing rotation of the wedge lock; a key on the convex surface of the smaller wedge portion cooperate with a recess formed in the semi-cylindrical cavity of the face of the leading wall to prevent axial movement of the wedge portion; a knock-out rod is provided to release the wedge lock for replacing of the impe