US20040092177A1

US20040092177A1 - Combination strut and rudder control assembly and method of forming same

Info

Publication number: US20040092177A1
Application number: US10/292,151
Authority: US
Inventors: Timothy Creighton
Original assignee: Acme Marine Group LLC
Current assignee: Acme Marine Group LLC
Priority date: 2002-11-12
Filing date: 2002-11-12
Publication date: 2004-05-13

Abstract

A combination strut and rudder control assembly (300) for use in a marine vessel includes a strut (301) used for providing support to a drive shaft assembly and a relatable shaft (311) positioned behind the strut (301) for controlling a rudder used to steer the marine vessel. The invention promotes efficient operation of the marine vessel though the use a strut (301) combined with a rudder control to enable proper alignment and mounting of these devices under the vessel's hull.

Description

TECHNICAL FIELD

This invention relates in general to marine vessels and more particularly to a marine inboard propulsion system.

BACKGROUND

Marine vessels such as small water skiing boats and the like typically utilize inboard propeller drive propulsion systems. Unlike an outboard type of propulsion drive, the inboard drive system includes a motor within the boat that includes a drive shaft extending through the hull to the stern. The drive shaft drives a propeller. The advantage of inboard drive as opposed to other types of marine propulsion systems is that the rotation of the propeller causes fewer vortex turbulents generated by the propeller at the surface of the water. This permits a rapid start of the boat while allowing a water skier to traverse across a fewer rear wake vortices generated by the propeller without the water turbulents generally associated with other types of marine drives, such as outboard and stern drive systems.

As seen in prior art FIG. 1, one typical implementation of a

inboard drive system

10 includes a motor 11 that uses a drive coupling 13 to rotate a drive shaft 15 through a stuffing box 17. As best seen in prior art FIG. 2, the stuffing box 17 is a cylindrical structure that allows the drive shaft 15 to pass though the hull 19 of the boat. The stuffing box 17 generally is a flexible hose or rubber housing 21 sealed by hose clamps 23 or the like. The stuffing box 17 is typically filled or “stuffed” with stuffing rope to prevent water leakage into the boat around the drive shaft 15. Although the stuffing box 17 may be integrally fastened to the hull 19, a user must continually insure that the packing nut 26 and hose clamps 23 are secured tightly so as to prevent water from entering inside the boat hull. Moreover, the stuffing box 17 must be precisely aligned with that portion of the boat's hull allowing the shaft to pass though. Since the shaft log 22 is fixed into position, any misalignment provides additional friction and wear to the shaft as it passes though the rubber housing 21 and packing nut 26.

In FIG. 3, as the

drive shaft

15 extends from the transmission coupling, through the stuffing box 17, to be supported by a strut 25. In some instances the drive shaft 15 may be enclosed within a protective oil lubricated cover or tube 27 to prevent water, mud and/or other liquids from entering the enclosure. Alternatively, the drive shaft 15 will extend directly through the strut 25 which provides support for the drive shaft 15 before reaching a propeller (not shown). The strut 25 typically includes a mounting blade 31 which acts to fix the strut 25 at some predetermined position on the hull of the boat. The strut further includes some type of water lubricated bearing (not shown) such as a cutless bushing to allow the drive shaft 15 to spin within the strut 25 using water as a lubricant. Problems typically associated with this type of arrangement include the friction and continual wear of the water lubricated bearing. Over time excessive play can develop within the strut to the extent that the drive shaft will move laterally and/or radially and is no longer held into a fixed position during rotation. Hence, the strut requires continual attention, repair and replacement of the water lubricated bearing to insure the most optimum and efficient transfer of power to the propeller 29 to help reduce the undesired effects of vibration and movement.

In view of these shortcomings in the prior art drive system, the need exists to construct a more efficient means for providing support of drive shaft during its rotation in a inboard drive marine vessel propulsion system. This will insure very little maintenance and an efficient means to transfer power to a marine propeller while aiding in the support of the driveline.

SUMMARY OF THE INVENTION

Briefly, according to the invention, there is provided a mounting support and rudder control assembly for use in an inboard drive marine propulsion system. The rear strut includes one or more bearing assemblies and well as a seal at both ends of a support housing for preventing water entry. Roller bearings are used to enhance rotational movement of a drive shaft while providing very little or no lateral movement. This greatly reduces wear and maintenance of the mounting support items to provide more efficient and less expensive operation of the marine vessel. A rudder control is further included to insure proper alignment and a better mounting though the use of a combination unit.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the present invention, which are believed to be novel, are set forth with particularly in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which: [0007]
FIG. 1 is a side view of the prior art inboard drive system for a marine vessel; [0008]
FIG. 2 is a side view of a prior art stuffing box used in an inboard drive propulsion system; [0009]
FIG. 3 is a side view of a prior art strut used in a inboard drive propulsion system; [0010]
FIG. 4 is a side cross-sectional view of the center support in accordance with the preferred embodiment of the invention; [0011]
FIG. 5 is a side cross-sectional view of the strut support in accordance with the preferred embodiment of the invention; [0012]
FIG. 6 is an exploded view of the center support; [0013]
FIG. 7 is an exploded view of the strut support; [0014]
FIG. 8 is a isometric view of another embodiment of the invention illustrating a strut and rudder control assembly; and [0015]
FIG. 9 is a side view illustrating the strut and rudder control assembly shown in FIG. 8.[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward. [0017]
Referring now to FIGS. [0018] 4 to 7, both a center support (FIG. 4) and a rear strut (FIG. 5) are shown and will be generally referred to as a center mounting support 100. It should be recognized by those skilled in the art that embodiments other than a center support or strut are also possible. Although terms such as “center” as used throughout, it will be recognized that this refers to a support in the general sense and not at the precise center of the marine vessel.
As seen in FIGS. 4 and 6, a [0019] dripless center support 100 is mounted to the hull 101 of a inboard drive marine vessel so as to allow a drive shaft assembly 103 to gain support thereby holding it into a fixed position during its rotation. Additionally, the center mounting support 100 facilitates rotational movement while reducing whip of the drive shaft assembly 103 as well as preventing water or other liquid or semi-liquid materials such as mud from entering though the exterior of the hull 101. In order to mount the center support 100 to prevent the entry of water while still providing a tight seal, the support 100 includes a flexible mounting ring 105. The mounting ring 105 may be a substantially circular ring molded to a rubber membrane 111 that is fitted to the exterior of the housing such as cylindrical shaft body 107 of the mounting support 100. The cylindrical shaft body 107 includes a rubber casing 110 to provide protection while immersed in water. The mounting ring 105 includes a plurality of mounting holes 108 to allow a screw 109 of other fastening means (not shown) to nest or secure the mounting ring 105 into a hole made within the hull 101. A mounting seal 106 is used to provide a watertight fit between the mounting ring 105 and rubber membrane 111. The mounting ring 105 is preferably comprised of a metallic material such as brass, steel, nibral, aluminum or the like to allow for a firm and secure mounting surface to the hull 101.
In order to allow the [0020] mounting ring 105 to be mounted to the hull 101 while still having a certain degree of flexibility, a rubber membrane 111 is adhered from the back of the ring. The membrane 111 is pliable allowing the cylindrical shaft body 107 of the center support 100 to move and flex to a limited degree about the mounting ring 105. This has a great advantage in that the center mounting support 100 may be mounted in any number of positions depending on the hull angle to the drive shaft assembly 103 which will extend through the hull 101. This gives the center support 100 even greater versatility since it is not rigidly mounted into position that would allow only one angle of entry for the drive shaft assembly 103. The flexible movement of the center support ring and tube also allows engine movement due to vibration, or shrink/swelling of steel, fiberglass and wood used in boat construction. The flex membrane 111 is adhered to the back of the mounting ring 105 and extends substantially along the sides of the cylindrical shaft body 107.
As best seen in FIGS. 4 and 5, the [0021] cylindrical shaft body 107 is constructed of a metallic body or other ridged structure that may include a rubberized coating. The cylindrical shaft body 107 facilitates movement of the drive shaft assembly 103 though the boat hull 101. The body is substantially hollow and includes a plurality of components to support the shaft in its rotational movement while providing the least amount of friction to the drive shaft assembly 103. The drive shaft assembly 103 passes through one or more needle bearing or roller bearing assemblies 113 and a sleeve 114 that are used within the cylindrical shaft body 107 to enhance rotational movement of the drive shaft assembly 103. Since the surface of the drive shaft assembly 103 will be manufactured of a relatively soft material such as stainless steel or the like, the sleeve 114 is adhered to the surface of the drive shaft assembly 103. This enables the harness of the surface of the drive shaft assembly to be increased to approximately a 60 Rockwell in order to allow the drive shaft assembly 103 to work more efficiently with the roller bearing assemblies 113. Preferably, each roller bearing assembly 113 includes a plurality of substantially spherical roller ball bearings that move within a closed track. As will be further recognized by those skilled in the art, a needle bearing assembly will also be applicable since the bearings would surrounds and rotate about the drive shaft assembly 103. The drive shaft assembly 103 is in contact with these bearings while the bearing work to both provides structural support for the drive shaft assembly 103 while facilitating rotation while within the center mounting support 100. Preferably each roller bearing assembly 113 would be sealed and would require no lubrication or other maintenance.
In order to prevent water and/or other harmful material from entering the [0022] center mounting support 100, one or more seal assemblies at used at one or both ends of the cylindrical shaft body 107 to insure that the components therein are impervious to external influence. A seal assembly may only be used at one end of the cylindrical shaft body 107 in the instance where one end of the support remains within the vessel and no water or other material would enter that end of the cylindrical shaft body 107. As will be evident to those skilled in the art, water or other materials coming in contact with the bearing assemblies 113 would damage bearing and other components within the center support 100. Each seal assembly includes a water deflector 115, gasket 117 and a seal 119. The water deflector 115 is frictionally engaged to the cylindrical drive shaft body 103 and is used to deflect water away from the outer face of the seal 119. Any water that does enter past the water deflector 115 is further trapped outside the roller bearing assemblies 113 by a seal 119. Typically the seal is made of a rubberized or other pliable material that will form a tight seal within the side body of the cylindrical shaft body 107 as well as the drive shaft 103. As best seen in FIG. 4, the cylindrical shaft body includes a counterbore 121 that is cut within the center support 100 to a predetermined depth thereby reducing the inner diameter of the cylindrical shaft body 107 at its ends. The counterbore 121 permits the seal 119 to obtain a tightly sealed fit within the counterbore 121 while the deflector 115 is used to further seal any gap between the water seal 119 and the support tube. The use of these components to from a seal assembly essentially prevents water from entering the ends of the cylindrical shaft body 107 that would work to damage the roller bearing assemblies 113 therein.
As best seen in FIGS. 5 and 7, this embodiment illustrates a [0023] strut support assembly 200 depicted in the form of a strut 201 used at the rear of the marine vessel for the supporting a drive shaft assembly 103 before being attached to a propeller mount 211 and propeller (not shown). Similar to the center support 100, the strut support assembly 200 includes a similar component structure within the strut 201 including a plurality of bearing assemblies and seal assemblies. The strut 201 includes a strut housing 203 having a blade 205 and flange 206 for fastening the strut 201 to the bottom of the vessel hull 207. The blade 205 is preferably tapered on the leading edge for efficiency and set at an angle to allow the drive shaft assembly 103 to extend under the hull 207 at some predetermined angle. The blade 205 with flange 206 is typically fastened against the hull 207 though the use of screw fasteners 209 or the like.
In FIGS. 8 and 9, another embodiment of the invention is illustrated as a combination strut and [0024] rudder control assembly 300. The strut and rudder control assembly 300 offers the advantage of having a strut like that shown in FIGS. 5 and 7, along with a rudder control. The strut and rudder control assembly includes a strut 301 having a substantially cylindrical housing 303. The housing 303 is connected to a blade 305 that is used to mount or fix the strut 301 at some predetermined angle to a connecting member 307. The connecting member 307 is preferable a substantially flat rectangular metallic surface that is used to mount the strut and rudder control assembly 300 to a boat's hull. A plurality of mounting holes 309 are provided for this purpose.
A substantially [0025] cylindrical shaft 311 is rotatable and used with a rudder (not shown) which is mounted though an rudder port 313 enabling the marine vessel to be steered in a specific direction. The cylindrical shaft 311 preferably includes a bearing 315 that enables the shaft to rotate smoothly without significant resistance and friction. Although both the strut 301 and cylindrical shaft 311 are shown located at both ends of the connecting member 307, it will be recognized by those skilled in the art that generally this may be mounted in any position with a rudder positioned behind the strut 301. The strut and rudder control assembly 300 provides a means to ensure proper placement and alignment of the strut 301 and rudder as well as better and simple means for mounting these devices to the marine vessel hull. This translates into easier maintenance and more efficient operation though the use of this invention.
The present invention allows for the quiet, smooth and efficient operation of an inboard drive marine vessel using the invention as described herein as a center support, strut and/or combination strut and rudder control assembly. The invention promotes more efficient operation by reducing the vessel's operating expense while providing little maintenance or repair as compared with stuffing boxers or water lubricated struts used in prior art designs. While the preferred embodiments of the invention have been illustrated and described, it will be clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.[0026]

Claims

What is claimed is:

1. A combination strut and rudder control assembly for use in a marine vessel comprising:

a strut used for providing support to a drive shaft assembly; and

a rotatable shaft positioned behind the strut for controlling a rudder used to steer the marine vessel.

2. A combination strut and rudder control assembly as in claim 1, wherein the strut and rotatable shaft are separated by a connecting member.

3. A combination strut and rudder assembly as in claim 1, wherein the strut is used to support a drive shaft assembly and includes:

a substantially cylindrical housing;

a plurality of bearing assemblies positioned within the cylindrical housing for promoting rotation of a drive shaft; and

a plurality of seals located at at least one end of the housing for preventing water from contacting the plurality of bearing assemblies.

4. A combination strut and rudder control assembly as in claim 1, wherein the plurality of bearing assemblies are needle bearings.

5. A combination strut and rudder control assembly as in claim 1, wherein the plurality of bearing assemblies are roller bearings.

6. A combination strut and rudder control assembly as in claim 1, further comprising a sleeve positioned within the cylindrical housing for frictionally engaging the plurality of bearing assemblies therein.

7. A combination strut and rudder control assembly as in claim 1, further comprising a plurality of deflectors located at each end of the cylindrical housing for deflecting water away from the plurality of seals.

8. A combination strut and rudder control assembly as in claim 1, further comprising at least one gasket for sealing the surface between the plurality of seals and the plurality of deflectors.

9. A combination strut and rudder control assembly as in claim 1, wherein the gasket is an “O” shaped ring.

10. A combination strut and rudder control assembly as in claim 1, further comprising a support member integrally connected with the housing for mounting the cylindrical housing to a fixed surface.

11. A combination strut and rudder as in claim 1, wherein the marine vessel has a inboard drive.

12. A steering assembly for use in a marine vessel comprising:

a strut for supporting a drive shaft; and

a rotatable collar for controlling the rotation of a rudder for steering the marine vessel.

13. A steering assembly as in claim 12, wherein the rotatable collar is a cylindrical shaft.

14. A steering assembly as in claim 12, wherein the cylindrical shaft includes a plurality of roller bearing to facilitate rotation.

15. A steering assembly as in claim 12, wherein the strut comprises:

at least one bearing positioned within the strut for facilitating movement of the engine drive shaft; and

a plurality seal assemblies for preventing external fluids from contacting the at least one bearing.

16. A steering assembly as in claim 12, wherein the bearing is a needle bearing.

17. A steering assembly as in claim 12, wherein the bearing is a roller bearing.

18. A steering assembly as in claim 12, wherein the seal assembly includes:

a pliable seal; and

a deflector for deflecting fluid from the seal.

19. A method for steering a marine vessel comprising the steps of:

providing a strut on a steering assembly for holding a drive shaft into a fixed position during rotation; and

providing a rotatable shaft on the steering assembly for holding a rudder to control steering of the marine vessel.

20. A method for steering a marine vessel as in claim 19, wherein the strut includes:

a substantially cylindrical housing;

at least one roller bearing assembly within the substantially cylindrical housing; and

a seal assembly for preventing water from contacting the at least one roller bearing assembly.

21. A method for steering a marine vessel as in claim 19, wherein the seal assembly includes at least one seal washer and a diverter for diverting water from the seal washer.

22. A method for steering a marine vessel as in claim 19, further comprising a gasket for sealing the area between the at least one seal washer and the diverter.

23. A method for steering a marine vessel as in claim 19, wherein the strut further includes a blade for mounting the strut at a predetermined angle in relation to the hull.