公开(公告)号：US20010013241A1

公开(公告)日：2001-08-16

申请号：US09775124

申请日：2001-02-01

Applicant: NSK Ltd.

Inventor： Akira Tsubouchi ,  Kiyoshi Okubo ,  Yasushi Watanabe

IPC: B21D022/06

CPC classification number: B62D3/126 ,  B21D15/04 ,  B21K1/767 ,  B21K1/768 ,  Y10T29/49474 ,  Y10T74/19949

Abstract: According to a method of manufacturing a hollow rack shaft, an approximately rectangular plate having a wide rack tooth portion is bent lengthwise. At this time, the plate has, at the central portion, a flat bottom portion on which rack teeth are formed later and a pair of mutually facing leg portions, and, in the vicinity of both ends, a semicircular bottom portion and a pair of mutually facing leg portions. The mutually facing leg portions at the central portion are bent into a gutter-like cross section having a larger clearance than the clearance of the mutually facing leg portions in the vicinity of both ends. The rack teeth are thus formed on the flat bottom portion through the plastic flow of the flat bottom portion and apart of material of the pair of leg portions of this flat bottom portion. The plate on which the rack teeth have been formed is formed into a tube having a hollow inner surface, by bending the plate and butt-joining the edge portions.

Abstract translation: 根据制造中空齿条轴的方法，具有宽齿条齿部的近似矩形的板被纵向弯曲。 此时，板在中央部具有稍后形成齿条齿的平坦的底部和一对相互相对的脚部，并且在两端附近具有半圆底部和一对 相互面对的腿部。 中心部分的相互相对的腿部弯曲成具有比两端附近的相互面对的腿部的间隙大的间隙的沟槽状横截面。 因此，齿条齿通过平底部的塑性流动以及该平底部一对腿部的材料的分开形成在平底部上。 已经形成齿条齿的板通过弯曲板和对接边缘部分而形成具有中空内表面的管。