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:
Apr. 24, 2001
Filed:
Oct. 04, 1999
Neil J. Dubois, Cranston, RI (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A marine propulsion assembly comprises a drive shaft, a first propeller fixed to the drive shaft and turnable therewith in a first direction, an annular array of gear teeth disposed on the first propeller and turnable therewith, a second propeller aligned with the first propeller, and an annular array of gear teeth disposed on the second propeller. Bevel gears are disposed between the first and second propellers and engaged with the first and second annular arrays of gear teeth. The bevel gears transmit rotation of the first propeller to the second propeller, such that the second propeller turns in an opposite direction relative to the first propeller.