Patent ID: 7147820
Filing Date: 2006-12-12
Classification: B22F,B30B

Abstract:
1. A method for minimizing the spread of the maximum compression forces in compacting powder, specifically metallic powder, by means of a powder press which has a die-plate, an upper ram, and at least one lower ram which are associated with a die-bore and are respectively operable by a hydraulic press cylinder, and a charging shoe movable on the die-plate along a predetermined path for filling the die-bore with the powder, wherein the maximum compression force of at least the upper ram is measured upon arrival at a predetermined position, the charging shoe, the die-plate, the upper ram and/or lower ram are vibrated at a predetermined frequency and amplitude during the filling operation and/or at the beginning of the compression procedure and, in addition, the filling time or the course of charging shoe motion in time are predetermined, characterized in that the frequency distribution of the maximum compression force values is determined at intervals and the standard deviation is determined therefrom for the maximum compression force, the standard deviation is compared to a predetermined value, if desired, and the vibration parameters, the course of motion in time and/or the path of charging shoe travel are varied according to a program until the standard deviation has reached a minimum value.