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:
Sep. 04, 2001
Filed:
Jan. 29, 1998
Applicant:
Inventors:
Michihiro Kuramochi, New Haven, CT (US);
Nobumitsu Takahashi, Gunma, JP;
Assignee:
NSK Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F16H 2/522 ;
U.S. Cl.
CPC ...
F16H 2/522 ;
Abstract
When balls,are discharged from a nut,in accordance with relative axial movement of the nut,and a screw shaft,, in order to prevent the balls,from contacting with thread grooves,and,of the nut,and the screw shaft,at three points, a counterbore,is formed around the thread groove,of the nut,in the vicinity of a discharge port for the balls,in the nut,. When the balls,are contacted with the thread grooves,and,, therefore, a four-point contact is always maintained. Consequently, reaction forces which are applied from the thread grooves,and,to the balls,balance with each other, whereby stable holding of the balls,is ensured.