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US5330374A Expired / Lapsed US ⏱️ 0.0 years remaining

Jet propulsion system

Assignee: Yamaha Marine Co Ltd
•
Filing: 1993-02-16
•
Granted: 1994-07-19
•
Expires: 2013-02-16
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Abstract

Abstract A jet propulsion system for a small watercraft including an arrangement for isolating the sound of water flowing through the water inlet portion of the jet propulsion unit from the occupants of the watercraft. This silencing is provided by providing a double wall on at least the portion of the jet propulsion unit water inlet portion juxtaposed to the passenger compartment to provide an insulating jacket. Water may be filled in the insulating jacket and this water can be derived by filling it with the coolant which is circulated through the engine.

Inventors

  • 👤 Tetsuya Ishino

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 19:17
CPC Classifications
B; B63; B63H; B63H21/00; B63H21/30; B63H21/305; B63H11/00; B63H11/02; B63H11/04; B63H11/08

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 123 words
A watercraft comprised of a hull, a jet propulsion unit mounted by said hull for propulsion of said watercraft, said jet propulsion unit being comprised of an outer housing comprised of a water inlet portion forming a water inlet opening and water inlet duct for drawing water from the body of water in which said watercraft is operating, said water inlet portion of said outer housing terminating at an outer housing impeller portion containing an impeller for pumping the water and an outer housing discharge nozzle, and means for providing with said outer housing an enclosed sound insulation jacket extending around at least a portion of said jet propulsion unit outer housing from substantially said water inlet opening to substantially said impeller portion.
Claim 2
Dependent Claim 123 words
A watercraft comprised of a hull, a jet propulsion unit mounted by said hull for propulsion of said watercraft, said jet propulsion unit being comprised of an outer housing comprised of a water inlet portion forming a water inlet opening and water inlet duct for drawing water from the body of water in which said watercraft is operating, said water inlet portion of said outer housing terminating at an outer housing impeller portion containing an impeller for pumping the water and an outer housing discharge nozzle, and means for providing with said outer housing an enclosed sound insulation jacket extending around at least a portion of said jet propulsion unit outer housing from substantially said water inlet opening to substantially said impeller portion.
Claim 3
Dependent Claim 47 words
A watercraft as set forth in claim 1 wherein the sound insulation jacket is provided at least around a part of said outer housing surrounding an impeller shaft driving the impeller and extending through a part of the water inlet duct for connection to a driving engine.
Claim 4
Dependent Claim 24 words
A watercraft as set forth in claim 2 wherein the sound insulation is provided by a double wall section of the water inlet portion.
Claim 5
Dependent Claim 19 words
A watercraft as set forth in claim 3 further including means for filling the sound insulation jacket with water.
Claim 6
Dependent Claim 29 words
A watercraft as set forth in claim 4 wherein the means for filling the sound insulation jacket with water comprises means for circulating water through said sound insulating jacket.
Claim 7
Dependent Claim 34 words
A watercraft as set forth in claim 1 wherein the jet propulsion unit is mounted within a tunnel formed in the hull of the watercraft and which tunnel is juxtaposed to a passenger compartment.
Claim 8
Dependent Claim 30 words
A watercraft as set forth in claim 6 wherein the water inlet portion is mounted in the tunnel in an area in proximity to a seat within the rider's area.
Claim 9
Dependent Claim 38 words
A watercraft as set forth in claim 1 wherein the sound insulation jacket is provided at least around a part of said outer housing surrounding a part of the water inlet duct for connection to a driving engine.
Claim 10
Dependent Claim 24 words
A watercraft as set forth in claim 8 wherein the sound insulation is provided by a double wall section of the water inlet portion.
Claim 11
Dependent Claim 19 words
A watercraft as set forth in claim 9 further including means for filling the sound insulation jacket with water.
Claim 12
Dependent Claim 29 words
A watercraft as set forth in claim 10 wherein the means for filling the sound insulation jacket with water comprises means for circulating water through said sound insulating jacket.

References Cited (Backward Citations)

US3292373A Cited
US3240179A Cited
US3306046A Cited
US3478712A Cited
US3785327A Cited
DE2359371A1 Cited
JPS5845199A Cited
US4813898A Cited
US4984528A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-07-18 1998-01-17 1998-07-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-07-18 2002-01-17 2002-07-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-07-18 2006-01-17 2006-07-19 $7700.00 Window Closed / Lapsed

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