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. 16, 1998
Filed:
Jun. 05, 1996
Takashi Iwashita, Hamamatsu, JP;
Sanshin Kogyo Kabushiki Kaisha, Shizuoka, JP;
Abstract
An exhaust system for an marine drive discharges exhaust gases between front and rear propellers of a counter-rotating propeller system. The discharge of exhaust gases between the propellers produces a cavitation effect about the rear propeller when accelerating from low speeds. As a result, the drive of the propellers accelerates more rapidly. At high speeds, however, the velocity of the exhaust gases carries the gases over the rear propeller principally in the vicinity of the rear propeller hub. No substantial cavitation effect occurs about the blades of the rear propeller at high speeds. As a result, the discharge of exhaust gases between the propellers causes no significant loss of propulsion efficiency when traveling at high speeds.