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:
Nov. 12, 1991
Filed:
Aug. 13, 1990
Toshikazu Ozawa, Iwata, JP;
Yu Motoyama, Iwata, JP;
Yamaha Hatsudoki Kabushiki Kaisha, Iwata, JP;
Abstract
An exhaust control valve arrangement for an in-line, two-cycle, crankcase compression engine which permits the porting arrangement to be rotated relative to the cylinder bore axis to achieve a compact configuration and wherein all of the exhaust control valves are operated by a single shaft assembly that extends parallel to a plane containing the cylinder bore axes. As a result of this orientation, the exhaust control valves provide an asymmetric exhaust port opening under at least some operative positions of the valves when the valves are in a flow obstructing position. A number of embodiments are disclosed which configure the exhaust control valves so that the port is symmetric in at least some operative obstructing positions of the valves. Also, several embodiments using curved valve configurations are disclosed.