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:
Jul. 15, 2003
Filed:
Nov. 27, 2001
Hiroshi Kato, Hamamatsu, JP;
Kabushiki Kaisha Somic Ishikawa, Tokyo, JP;
Abstract
An intermediate molding ( ) is formed so that a cylindrical arm-to-be portion ( ) projects from the cylindrical outer surface of a body portion ( ) of the arm-to-be portion ( ). The arm-to-be portion ( ) has a given thickness and a hole ( ) with a diameter greater than the inner diameter of a projecting connector portion ( ) of an arm portion ( ). A pair of flat face portions ( ) extending parallel to the axis of the body portion ( ) are formed on the cylindrical outer surface of the arm-to-be portion ( ). A tap ( ) that has an external thread ( ) formed along its cylindrical outer surface is inserted into the hole ( ) of the arm-to-be portion ( ). Concave faces ( ),( ) are concaves respectively formed on the opposing surfaces of an upper die ( ) and a lower die ( ) so as to have a shape like a half cylinder with a curvature corresponding to that of the cylindrical outer surface of the projecting connector portion ( ). The concave faces ( ),( ) sandwich and apply pressure to the arm-to-be portion ( ), thereby narrowing the arm-to-be portion ( ) and forming an internal thread ( ) in the cylindrical outer surface of the hole ( ) of the arm-to-be portion ( ). With the tap ( ) being removed while being rotated, formation of the arm portion ( ) is completed. Compared with a method that calls for forming an internal thread ( ) by threading with an external thread ( ) of the tap ( ), the method of the invention enables the easier and quicker formation. The invention also prevents wear of the tap ( ) and enables the easy formation of the projecting connector portion ( ) of the arm portion ( ) having stable characteristics and a desired internal thread ( ).