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:
Dec. 28, 2004
Filed:
Dec. 26, 2002
Nobuaki Hinago, Hatano, JP;
Chikara Saeki, Hatano, JP;
Kiyonori Ozeki, Hatano, JP;
Hideki Iwamoto, Hatano, JP;
Kabushiki Kaisha Kobe Seiko Sho, Kobe, JP;
Abstract
Disclosed is a producing method which allows low-cost and highly productive production of a seamless tube with a grooved inner surface having a smooth outer surface and an inner surface formed with plural types of grooves such that a protrusion is not formed at the produced seamless tube with a grooved inner surface. The tube is reduced in diameter by using a die and a plug. Then, the outer surface of the tube is pressed against a grooved plug by means of a pair of rolls such that a groove is formed in a portion of the inner surface of the tube. The process flattens the cross-sectional configuration of the tube in the direction in which the tube is pressed with the rolls. Subsequently, a sizing process using a die is performed with respect to the tube such that the tube has a generally circular configuration. Then, the outer surface of the tube is pressed against a grooved plug by means of another pair of rolls disposed such that the rotation axes thereof are orthogonal to the rotation axes of the rolls, whereby a groove is formed in a portion of the inner surface of the tube. Thereafter, the tube is subjected to a diameter reducing process using a die.