1. Field of the Invention
This invention relates to vessel propulsion systems, and in particular to a self-contained hydraulic thruster for vessel.
2. Background of the Invention
Marine thrusters typically mount on barges and flat boats, and are used as propulsion for these vessels. One type of marine thruster employs a prime mover such as a diesel engine driving a hydraulic pump, together known as a “power pack”, and the resultant pressurized hydraulic fluid may be employed to drive a propeller attached to a lower unit.
There are a number of problems associated with currently available marine thrusters. Where a centrally located tiltable lower unit has been retracted and tilted backwards for transportation, storage, maintenance, cleaning, etc., the protruding upper end of the lower unit interferes with the helm and helm platform, and prevents full upward tilting of the retracted lower unit. Therefore, it would be desirable to provide a marine thruster which may be retracted and then fully tilted.
Another problem with existing designs: the hydraulic fluid reservoir is disposed on the base of the marine thruster, where it is incapable of supplying enough fluid head to self-prime the power pack, and to facilitate hydraulic fluid flow to the hydraulic power pack. Thus, it would be desirable to provide a hydraulic fluid reservoir which is elevated to a substantial height above the level of the base upon which the power pack is mounted.
Still another problem is where a marine thruster's single lower unit propeller does not supply enough power to adequately propel a vessel upon which it is mounted. It would therefore be desirable to provide a marine thruster with more than one lower unit, for increased power.
Existing Designs
In addition, the mounting of the hydraulic fluid reservoir on the base of this design provides inadequate flow from the hydraulic fluid tank for self-priming and gravitational flow from the hydraulic fluid tank to the power pack.
It is an object of the present invention to provide a self-contained hydraulic thruster for vessel with an elevated hydraulic fluid reservoir. Design features allowing this object to be accomplished include a hydraulic fluid reservoir mounted on a helm platform which is elevated a substantial height above a base to which a hydraulic power pack is mounted. Benefits associated with the accomplishment of this object include power pack self-priming, and facilitated hydraulic fluid flow from the hydraulic fluid reservoir to the hydraulic power pack.
It is another object of the present invention to provide a self-contained hydraulic thruster for vessel whose lower unit(s) may be retracted and tilted up without interference from the helm platform. Design features allowing this object to be accomplished include at least one lower unit mounted at an end of a lower unit mounting member, the lower unit being laterally offset from a steering platform. Advantages associated with the accomplishment of this object include more efficient lower unit stowing for storage and/or transportation, greater tilt achievable (close to 90 degrees), the ability to tilt the propellers and lower unit completely out of the water for servicing and cleaning, decreased corrosion due to the ability to tilt up the lower units and propellers completely out of the water when not in use to reduce corrosion, and greater retraction of the lower unit.
It is yet another object of this invention to provide a self-contained hydraulic thruster for vessel which is economical to build. Design features allowing this object to be achieved include the use of components made of readily available materials, and commercially available components such as an existing hydraulic actuator, hydraulic power pack, hydraulic fluid reservoir, lower unit, propeller, steering gear, drive gear, and hydraulic lines. Benefits associated with reaching this objective include reduced cost, and hence increased availability.
The invention, together with the other objects, features, aspects and advantages thereof will be more clearly understood from the following in conjunction with the accompanying drawings.
Ten sheets of drawings are provided. Sheet one contains
As may be observed in these figures, hydraulic thruster 20 comprises power pack 24 mounted to the front (or forward end) of base 22, and helm platform 26 mounted to the rear (or aft end) of base 22. Helm platform 26 is mounted a substantial height above base 22. Helm 28 and hydraulic fluid reservoir 30 are mounted atop helm platform 26.
In this configuration, hydraulic fluid within hydraulic fluid reservoir 30 is urged by gravity to flow to power pack 24, thus improving hydraulic fluid flow from hydraulic fluid reservoir 30 to power pack 24, and rendering power pack 24 self-priming. These are two important advantages to mounting hydraulic fluid reservoir 30 atop helm platform 26, at a substantial height above base 22.
In the preferred embodiment, hydraulic fluid reservoir floor height 33 was equal to or greater than 75% of hydraulic pump height 54. It was determined experimentally that this minimum hydraulic fluid reservoir floor height 33 is optimum to achieve the afore-mentioned benefits of improving hydraulic fluid flow from hydraulic fluid reservoir 30 to hydraulic pump 52, and rendering hydraulic pump 52 and its associated hydraulic lines self-priming.
Hydraulic thruster 20 further comprises lower unit 37 rotatably, tiltably and retractably attached to the rear of hydraulic thruster 20, laterally offset from helm platform 26.
Lower unit 37 comprises tube 38, housing 32, and propeller 40. Propeller 40 is disposed at a distal end of tube 38, and serves to provide thrust in the water to hydraulic thruster 20. Tube 38 is rotatably and reciprocatingly attached to housing 32, whereby a steering function is provided to tube 38 and propeller 40, as indicated by arrow 68 in
Housing 32 also comprises housing lower unit mounting member bore 35 sized to rotatably admit lower unit mounting member 36. Thus, a tilt function is provided to lower unit 37 by means of the rotatable attachment between housing 32 and lower unit mounting member 36, as indicated by arrow 72 in
As may be observed in
As in the embodiment hydraulic thruster 20 depicted in
Hydraulic thruster 20 further comprises two lower units 37 rotatably, tiltably and retractably attached to the rear of hydraulic thruster 20, each laterally offset from helm platform 26, on either side of helm platform 26.
Each lower unit 37 comprises tube 38, housing 32, and propeller 40. Propeller 40 is disposed at a distal end of tube 38, and serves to provide thrust in the water to hydraulic thruster 20. Tube 38 is rotatably and reciprocatingly attached to housing 32, whereby a steering function is provided to tube 38 and propeller 40, as indicated by arrow 73 in
Housing 32 comprises housing lower unit mounting member bore 35 sized to rotatably admit lower unit mounting member 36. Thus, a tilt function is provided to lower unit 37 by means of the rotatable attachment between housing 32 and lower unit mounting member 36.
In the embodiments depicted in
Due to the tiltable attachment between each housing 32 and base 22, each lower unit 37 may be tilted up and down relative to base 22 as indicated by arrow 82 in
In all embodiments of the instant invention, prevention of interference between lower unit(s) 37 and helm platform 26 enables lower unit(s) 37 to be fully tilted up for storage, transportation, maintenance, etc., as depicted in
While the instant disclosure teaches a number of embodiments wherein at least one lower unit is tiltably attached to a base, laterally offset from a helm platform, this disclosure is intended to embrace any means of tiltably attaching a lower unit to a base, laterally offset from a helm platform. Other means of attachment might include hinge(s), a ball-in-socket arrangement, a lower unit tiltably attached to a lower unit mounting tube, attaching the lower drive housing to the end of a boom (e.g. remove the bucket from a track-hoe or a back-hoe, attach housing 32 to it and lower it down into the water, like a knuckle boom), etc.
In the preferred embodiment, base 22, helm platform 26, helm 28, hydraulic fluid reservoir 30, lower unit mounting member 36, and lower units 37 were made using metal, synthetic material, corrosion-resistant metal, corrosion-resistant metal fasteners, welded construction, or other appropriate materials and processes. Power pack 24, propeller 40, and actuators 46 were commercially available items.
While a preferred embodiment of the invention has been illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit of the appending claims.
This utility patent application is a Continuation-In-Part U.S. utility patent application of Ser. No. 12/924,356 filed Sep. 24, 2010 entitled Self-Contained Hydraulic Thruster for Vessel which is a Continuation-In-Part of U.S. utility patent application Ser. No. 12/806,274 filed Aug. 9, 2010 entitled Hydraulic Thruster for Vessel, which is a Continuation-In-Part of U.S. utility patent application Ser. No. 12/800,026 filed May 6, 2010 entitled Modular Hydraulic Thruster System for Vessel, which is a Continuation-In-Part of U.S. utility patent application Ser. No. 12/381,245 filed Mar. 10, 2009 now U.S. Pat. No. 7,883,384 entitled Self-Contained Hydraulic Thruster for Vessel, which is a Continuation-In-Part of U.S. utility patent application Ser. No. 11/999,531 filed Dec. 6, 2007 which issued as U.S. Pat. No. 7,654,875 on Feb. 2, 2010 entitled Self-Contained Hydraulic Thruster for Vessel, which was based upon U.S. provisional patent application Ser. No. 60/903,400 filed Feb. 26, 2007 entitled Self-Contained Hydraulic Thruster for Vessel; and claims the benefit of the earlier filing date of these applications.
Number | Name | Date | Kind |
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2936730 | Patty, Jr. | May 1960 | A |
4878864 | Van Bentem | Nov 1989 | A |
6332817 | Nakamura | Dec 2001 | B1 |
6799528 | Bekker | Oct 2004 | B1 |
7654875 | Williams | Feb 2010 | B1 |
Number | Date | Country | |
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20110081811 A1 | Apr 2011 | US |
Number | Date | Country | |
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60903400 | Feb 2007 | US |
Number | Date | Country | |
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Parent | 12924356 | Sep 2010 | US |
Child | 12976246 | US | |
Parent | 12806274 | Aug 2010 | US |
Child | 12924356 | US | |
Parent | 12800026 | May 2010 | US |
Child | 12806274 | US | |
Parent | 12381245 | Mar 2009 | US |
Child | 12800026 | US | |
Parent | 11999531 | Dec 2007 | US |
Child | 12381245 | US |