Ntn Corporation

Hiroki Mukai

Hirokazu Ooba

Keisuke Sone

Kazuhiko Yoshida

Arito Matsui

A hollow shaft, which is usable with a constant velocity universal joint, has an increased static torsional strength and torsional fatigue strength of a small diameter portion (small diameter portion having a smooth outer peripheral surface) formed near a spline at an end portion of the hollow shaft, and has a reduced manufacturing cost. The hollow shaft is molded by plastic working from a tubular blank, and subjected to quench hardening treatment. The quench hardening treatment includes carburizing and quenching treatment. The hollow shaft includes a softened section formed in a part of the hollow shaft by local heating treatment after carrying out the carburizing and quenching treatment.

Hollow shaft and constant velocity universal joint

A link actuating device includes input side and output side link hubs, and two sets of link mechanisms. Each of the link mechanisms is a three-link-chain link mechanism including four revolute pairs, and includes input side and output side end links rotatably connected to the input side and output side link hubs and an intermediate links rotatably connected to input side and output side end links. The link mechanism have a positional relationship in which the revolute pair axes between the link hubs and the end links are located on the same plane and cross each other. At least one of the two sets of link mechanisms is provided with interlocking unit that interlocks the input side end link and the output side end link to each other so as to be rotationally displaced.

Growing community of inventors

Shizuoka, Japan

Hiroki Mukai