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. 13, 2022
Filed:
Dec. 04, 2020
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Takeshi Hashizume, Mishima, JP;
Toyota Jidosha Kasbushiki Kaisha, Toyota, JP;
Abstract
A piston has a top surface composed of porous alumina. Top surface includes a first region and a second region. The first region includes a part or all of a region connecting to an outer periphery of the top surface. The second region is adjacent to the first region. The second region includes some or all of the region inside the top surface. The porous alumina formed on the second region is thinner than that formed on the first region. In a manufacturing method of a piston, first, a casting piston made of aluminum alloy is prepared. Then, a casting surface in a first region is removed, thereby a material surface is exposed. Then, anodization of the casting piston is performed, whereby a porous alumina is formed on the first and second regions.