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. 30, 2014
Filed:
Mar. 16, 2011
Ryotaro Takada, Utsunomiya, JP;
Mayumi Saruyama, Utsunomiya, JP;
Yositaka Tsujii, Utsunomiya, JP;
Honda Motor Co., Ltd., Tokyo, JP;
Abstract
Provided is an aluminum alloy piston for an internal combustion engine. In the internal combustion engine, the piston moves back and forth in a sleeve made of grey cast iron or an aluminum alloy. Further, the piston, which is made from silver, silver alloy, copper, or copper alloy, is provided with a film that covers the scoring that is formed on the piston skirt and there are undulations in the surface of the film, formed from protrusions and depressions. There is a difference of 8-15 μm between the lowest point of the depressions and the highest point of the protrusions. The pitch of adjacent protrusions corresponds to the pitch of projections in the scoring. In addition, the arithmetic average roughness (Ra) of the protrusion peaks does not exceed 60 nm.