Patent ID: 7761995
Filing Date: 2010-07-27
Classification: B22F,B30B,F16H,Y10T

Abstract:
1. A pressing method for molding a gear wheel with a multiple helical toothing comprising the steps of: a) introducing a compactable material into a chamber of a pressing tool which includes a matrix, a first molding tool part and a second molding tool part, wherein said first molding tool part and said second molding tool part are mounted such that they can be translated back and forth within the matrix along a longitudinal axis and rotated about the longitudinal axis and each comprises at least one cylindrical surface with a helical toothing; b) compacting the material in said chamber by moving the molding tool parts in a combined axial and rotational movement along and about the longitudinal axis towards each other thereby pressing the material into the cylindrical surfaces with the helical toothings, in order to obtain the gear wheel with helical toothings corresponding to the cylindrical surfaces with helical toothings of the molding tool parts; c) exposing the helical toothings of the gear wheel by translating the molding tool parts away from each other along the longitudinal axis and by the molding tool parts each performing a rotational movement about the longitudinal axis as they are translated while the gear wheel is performing a linear axial sliding movement relative to the matrix; and d) removing the molded body from the pressing tool; further comprising the steps of sintering the pressed gear wheel and molding a collar on the gear wheel by the pressing method when machined down, wherein the collar runs about a rotational axis of the gear wheel between a first helical toothing and a second helical toothing formed by the helical toothings of the molding tool parts.