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:
Jun. 23, 1992
Filed:
Oct. 31, 1990
Nobuaki Wakita, Nagoya, JP;
Shigeyuki Hori, Toyota, JP;
Yorishige Maeda, Toyota, JP;
Seizi Oomura, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
An internal combustion engine having its cylinders tilted at an angle of less an than 90 degrees relative to a vertical axis is provided with a oil drain mechanism for drainign excess oil that collects when the engine stops. For this purpose, an oil drain hole, which communicates with an interior of the piston body to drain the lubricating oil, is formed in the inner wall of an oil ring groove in such a way as to be located below the center line of the piston body. Both ends of the oil drain hole are set lower than the lowest portion of a piston head. Therefore, it is possible to prevent lubricating oil from entering the combustion chamber when the engine stops, without providing a whirl-stop on piston rings.