Nsk Corporation

Shigemi Tsukamoto

Tatsuo Wakabayashi

Chuichi Sato

Eishi Shibuya

Katsuyuki Kawamura

Hirohide Ishida

Hidenori Shinno

With respect to an outer ringin which a diameter Dof a first outer ring racewayis greater than a diameter Dof a second outer ring raceway(D&#x3e;D), a method is realized which facilitates the entry of a grinding toolinto an inner side of the outer ring when these both outer ring racewaysandare subjected to a grinding process. The grinding toolis made to enter the inner side of the outer ringthrough an opening on a side close to the first outer ring raceway

Manufacturing method of an outer ring for a bearing unit

In a wheel supporting rolling bearing unit in which pitch circle diameters of ballsin an outside row and an inside row are made different, contact angles &#x3b1;, &#x3b1;of the ballsin the two rows in a completed state are equal to each other. Initial contact angles &#x3b2;, &#x3b2;of the two rows are smaller than predetermined contact angles &#x3b1;, &#x3b1;. The extent [&#x3b1;&#x2212;&#x3b2;] to which the initial contact angle &#x3b2;of the ballsin the inside row is made smaller than the predetermined contact angle &#x3b1;of the ballsis made larger than the extent [&#x3b1;&#x2212;&#x3b2;] to which the initial contact angle &#x3b2;of the ballsin the outside row is made smaller than the predetermined contact angle &#x3b1;of the balls{[&#x3b1;&#x2212;&#x3b2;]&#x3e;[&#x3b1;&#x2212;&#x3b2;]}. By this configuration, imparting the predetermined contact angles &#x3b1;, &#x3b1;to the ballsin the two rows in the completed state, and the preloads and contact angles of the ballsin the two rows are made proper.

Method for manufacturing wheel supporting rolling bearing unit and method for inspecting double row rolling bearing unit

An electrorheological fluid damper for a slide mechanism including a base and a table, is made up of base-side conductive arcuate pipes different in diameter (serving as a positive electrode), and table-side conductive arcuate pipes different in diameter (serving as a negative electrode) which are arranged alternately in such a manner that they are coaxial with one another, so that the contact areas of the electrodes which are in contact with the electrorheological fluid are increased without increase of the size of the damper itself. When the table is being slid, no voltage is applied to the electrorheological fluid, so that the viscosity of the electrorheological fluid is minimum, being of only its solution, and when the table is stopped, voltage is applied to the electrorheological fluid, so that the viscosity of the electrorheological fluid is increased. Thus, the electrorheological fluid damper requires no high voltage and is not bulky, and is high both in positioning accuracy and in shock absorbing performance.

Growing community of inventors

Fujisawa, Japan

Shigemi Tsukamoto