METHOD FOR MANUFACTURING INTEGRATED ALUMINUM ALLOY BICYCLE FRONT FORK

摘要

A method for manufacturing an integrated aluminum alloy bicycle front fork is revealed. Aluminum alloy is extruded to form substrate having three rectangular bars. Cut the substrate to get a blank. The blank is set into a mold for forging the three rectangular bars into three round bars. Then burr and waste material are removed. Next the blank is set into another mold for extruding the three round bars and the three round bars are punched to have guide holes. The round bars are drilled along the guide holes and penetrated to form round tubes. A tube opening of two round tubes is flattened and narrowed. Then the two round tubes are bent downward to form fork tubes of a front fork. The rest tube forms a front fork stem. Thereby an integrated light weighted front fork with good structural strength and beautiful appearance is produced.

主权项

1. A method for manufacturing an integrated aluminum alloy bicycle front fork comprising the steps of:
A. preparing aluminum alloy substrate with a certain length; B. extruding the aluminum alloy substrate to form substrate having three rectangular bars connected integrally and arranged radially; C. cutting the substrate having three rectangular bars to get a blank with a certain length; D. setting the blank into a cavity of a first mold for the first die forging so that the blank is forged to have the same shape as the shape of the cavity of the first mold; the three rectangular bars of the blank are forged and molded into three round bars while burr and waste material are generated; E. cutting and removing the burr and waste material of the blank generated at the first die forging; F. setting the blank into a cavity of a second mold for the second die forging so that the blank is forged to have the same shape as the shape of the cavity of the second mold and the three round bars of the blank are extruded and extended in the cavity; simultaneously using a punch in the cavity driven into the three round bars of the blank for punching and molding a front part of each of the three round bars to form guide holes; G. drilling the blank along the guide holes on the front part of the round bar by drills and penetrating the three round bars of the blank to form three round tubes each of which is a hollow blank tube; H. shaping two of the three round tubes so that a front part of each of the two round tubes gets tapered toward a tube opening of the round tube and then flattening and narrowing the tube opening; and I. bending the two round tubes having the flattened and narrowed tube opening respectively downward and enabling the two round tubes parallel to each other, having a certain interval therebetween to form two fork tubes of a front fork while the rest one round tube is located over and between the two fork tubes to form a stem of the front fork.