The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 29, 2007
Filed:
Dec. 03, 2002
Applicants:
Shigeru Okita, Gunma, JP;
Tsutomu Ohkubo, Gunma, JP;
Daisuke Maruyama, Gunma, JP;
Inventors:
Assignee:
NSK Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16H 25/22 (2006.01);
U.S. Cl.
CPC ...
Abstract
The invention provides a ball screw apparatus which suppresses abrasion and damage by competition of balls, controls spaces between retaining pieces and balls, and prevents retaining pieces from falling, thereby enabling to more improve operating ability. The retaining pieces are positioned between the balls running in a ball rolling path, such that a sum total of the spaces between the retaining pieces and the balls is 50% or less of an outer diameter size of the retaining piece, and at the same time a contact angle between the retaining piece and the ball is 25° or above to 40° or below.