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:
Jan. 19, 2010
Filed:
Feb. 27, 2006
Kazuhiko Ueda, Nara, JP;
Kazuhiko Ueda, Nara, JP;
Sharp Kabushiki Kaisha, Osaka-shi, JP;
Abstract
A cup-shaped sleeve is made mainly of a resin and has an end where a plurality of pieces of a permanent magnet are insert-molded. An auxiliary ring made mainly of a resin is provided along an inner peripheral surface of the cup-shaped sleeve other than an inner peripheral surface thereof where the permanent magnet is provided. The auxiliary ring has its inner peripheral surface identical to the inner peripheral surface of the permanent magnet or located outside relative to the inner peripheral surface of the permanent magnet. When the cup-shaped sleeve is resin-molded, the resin which is a component of the cup-shaped sleeve is prevented from shrinking inward. Therefore, contact between the resin supporting the permanent magnet and the cylinder is prevented. Accordingly, a linear drive device is obtained in which the reciprocation of the piston is prevented from being hindered.