US3884174A

US3884174A - Marine noise and vibration isolation system

Info

Publication number: US3884174A
Application number: US388374A
Authority: US
Inventors: Robert T Larsen
Original assignee: Outboard Marine Corp
Current assignee: Outboard Marine Corp
Priority date: 1973-08-15
Filing date: 1973-08-15
Publication date: 1975-05-20
Anticipated expiration: 1992-05-20
Also published as: JPS5841240B2; JPS5048693A; CA1014017A

Abstract

Disclosed herein is an outboard motor mounting arrangement comprising a first bracket adapted to be secured to the transom of a boat and including a lower generally vertically extending and rearwardly facing surface and an upper generally vertically extending and forwardly facing surface located in rearwardly spaced relation to and above the rearwardly facing surface, together with a second bracket and including an upper generally vertical and rearwardly facing surface located in opposed and spaced relation to the forwardly facing surface of the first bracket and a lower generally vertical and forwardly facing surface in spaced and opposed relation to the rearwardly facing surface of the first bracket, and first and second noise and vibration isolating mounts respectively extending between the upper forwardly and rearwardly facing surfaces and the lower forwardly and rearwardly facing surfaces.

Description

United States Patent 1 Larsen 11] 3,884,174 [451 May 20, 1975 [75] Inventor: Robert T. Larsen, Menomonee Falls, Wis,

[73] Assignee: Outboard Marine Corporation,

Waukegan, Ill.

[22] Filed: Aug. 15, 1973 21 Appl. No.: 388,374

[52] US. Cl. 115/17; 248/4; 248/9; 248/20 [51] Int. Cl B63h 21/26; B63h 21/30 [58] Field of Search 115/17, 18, 34, 41; 248/4, 248/15, 22, 9, 20

[56] References Cited UNITED STATES PATENTS 1,861,048 5/1932 Conover 248/4 X 2,209,592 7/1940 Beck 248/4 2,738,751 3/1956 Hogberg 115/17 2,740,368 4/1956 Irgens et a1. 115/18 3,586,272 6/1971 Pestell 248/22 3,599,594 8/1971 Taipale 115/17 FOREIGN PATENTS OR APPLICATIONS 560,537 4/1957 Italy 248/4 Primary ExaminerTrygveM. Blix Assistant Examiner-Galen L. Barefoot Attorney, Agent, or FirmMichael, Best & Friedrich [57] ABSTRACT Disclosed herein is an outboard motor mounting arrangement comprising a first bracket adapted to be secured to the transom of a boat and including a lower generally vertically extending and rearwardly facing surface and an upper generally vertically extending and forwardly facing surface located in rearwardly spaced relation to and above the rearwardly facing surface, together with a second bracket and including an upper generally vertical and rearwardly facing surface located in opposed and spaced relation to the forwardly facing surface of the first bracket and a lower generally vertical and forwardly facing surface in spaced and opposed relation to the rearwardly facing surface of the first bracket, and first and second noise and vibration isolating mounts respectively extending between the upper forwardly and rearwardly facing surfaces and the lower forwardly and rearwardly facing surfaces.

19 Claims, 7 Drawing Figures PATENTEU HAYZO i975 SHEET 10F 3 PATENTEU HAY 2 0 I975 SHEET 2 OF 3 155mm :mmsm

SHEET 3 OF 3 MARINE NOISE AND VIBRATION ISOLATION SYSTEM BACKGROUND OF THE INVENTION The invention relates generally to noise and vibration isolation systems or arrangements for outboard motors. More particularly, the invention relates to outboard motor mounting arrangements and to outboard motors and to boats. Still more particularly, the invention relates to noise and vibration isolating systems and arrangements for preventing or at least reducing noise and vibration transmission from an outboard motor propulsion unit to a supporting boat hull.

Prior examples of arrangements for isolating the noise and vibration associated with a marine propulsion unit from a supporting boat are found in the following US. Pat. Nos:

Long 2,630,991 issued March 10. 1953 Irgens 2,740,368 issued April 3, 1956 Rose 2,890,674 issued June 16. 1959 Kiekhaefer 2,911.96] issued November It), 1959 Kiekhaefer 2,916,007 issued December 8, 1959 Watkins 3,002,489 issued April 7, 1964 Mohr 3.127866 issued April 7, 1964 Watkins 3,452,704 issued July 1, 1969 Taipale 3599.594 issued August 17. 1971 Wick 3.613.631 issued October 19, 1971 SUMMARY OF THE INVENTION The invention provides a noise and vibration isolating mounting system for an outboard motor comprising a first member or bracket adapted to be secured to the transom of a boat and including a lower surface and an upper surface located in rearwardly spaced relation to and above the lower surface, together with a second bracket or member adapted to support an outboard motor, located between the upper and lower surfaces of the first bracket and including an upper surface located in spaced relation to the upper surface of the first bracket and a lower surface in spaced relation to the lower surface of the first bracket, and first and second noise isolating means or isolators respectively extending between the upper surfaces and the lower surfaces.

In further accordance with the invention the lower surface of the first bracket extends generally vertically and is rearwardly facing in opposed relation to the lower surface of the second bracket which extends generally vertically and is forwardly facing. The upper surface of the first bracket extends generally vertically and is forwardly facing in opposed relation to the upper surface of the second bracket which extends generally vertically and is rearwardly facing.

In still further accordance with the invention, the noise and vibration isolating mounting arrangement can also include an upwardly facing surface on the first bracket together with a downwardly facing surface on the second bracket in opposed and spaced relation to the upwardly facing surface on the first bracket, together with a third noise isolating means or isolator between the opposed upwardly and downwardly facing surfaces.

The isolators can, in accordance with the invention, be either air bags, or soft rubber mounts, or other suitable noise and vibration isolating means.

Also provided is an outboard motor which incorporates a noise and vibration isolating arrangement embodying the invention and which is adapted to be mounted on the transom of a boat.

Still further, there is provided a boat which incorporates a noise and vibration isolating arrangement or system embodying the invention and which is adapted to receive or support a conventional outboard motor.

One of the principal features of the invention is the provision of an outboard motor noise and vibration isolating arrangement providing superior efficiency in preventing, or at least reducing, noise and vibration transmission from a marine propulsion unit to a supporting boat hull.

Another of the principal features of the invention is a marine propulsion device which is adapted to be mounted on the transom of a boat and which incorporates a noise and vibration isolation system between a tilt bracket and transom attachment bracket.

Another of the principal features of the invention is the provision of a boat hull including a noise and vibration isolation arrangement which is adapted to support an outboard motor.

Other features and advantages of the invention will become known by reference to the following drawings, general description and appended claims.

DRAWINGS FIG. 1 is a side elevational view, of an arrangement for mounting an outboard motor to the stern of a boat hull.

FIG. 2 is an enlarged rear elevational view of the mounting arrangement employed in FIG. 1.

FIG. 3 is a side elevational view, partially in section, of the mounting arrangement employed in FIG. 1.

FIG. 4 is a view similar to FIG. 2 illustrating another embodiment of the invention.

FIG. 5 is a partially broken away view similar to FIG. 3, further illustrating the embodiment shown in FIG. 4.

FIG. 6 is a fragmentary view of a marine propulsion device integrally embodying a noise and vibration isolating system in accordance with the invention.

FIG. 7 is a fragmentary view of a boat hull integrally embodying a noise and vibration isolating system in accordance with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Before explaining the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purposes of description and should not be regarded as limiting.

GENERAL DESCRIPTION Shown in FIG. 1 is a noise and vibration isolating system or arrangement 11 for mounting an outboard motor 13 to a boat transom 15. The outboard motor 13 is of conventional structure including a clamp or transom bracket 17, a swivel bracket 18 connected to the clamp bracket 17 by a tilt pin 19 and a propulsion unit 21 which includes a power head 23 and a lower unit 25 supporting a propeller 27 and which is connected to the swivel bracket 18 through a king pin 29 journaled by the swivel bracket 18. The outboard motor can be either with or without conventional isolation mounts between the king pin 29 and the propulsion unit 21 as shown for instance in the previously identified U.S. Irgens, Kiekhaefer, Taipale and Wick patents.

In accordance with the invention, the outboard motor mounting arrangement 11 includes, as shown best in FIGS. 2 and 3, a first member or mounting or transom bracket which is adapted to be fixedly connected to the transom 15, as by bolting or the like. The mounting bracket 33 includes a lower, generally vertical and rearwardly facing surface 35 and an upper generally vertically and forwardly facing surface 37 which is located in rearwardly spaced relation to and above the lower rearwardly facing surface 35. More specifically, in the construction illustrated in FIGS. 1 through 3, the mounting bracket 33 includes a mounting plate 39 which includes the lower rearwardly facing surface 35 which comprises two laterally adjacent surface portions 36 and 38. The upper forwardly facing surface 37 includes (See FIGS. 2 and 3) laterally spaced portions 41 and 43 which are supported from the mounting plate 39 by respective laterally spaced

bridging structures

45 and 47 which can take various forms. In the illustrated construction, each bridging structure is in the form of three channel shaped

sections

49, 51 and 53 which are welded together to form U-shaped bracket portions which are respectively connected by bolts 40 to the plate 39.

lnterposed between the lower rearwardly facing surface 35 and the upper forwardly facing surface 37 of the mounting bracket 33 is a generally vertically extending second member or intermediate plate or bracket 61 which is generally in the form of a plate extending between the forwardly and rearwardly spaced

surfaces

35 and 37 of the mounting bracket 33, and which forms a support to which the clamp bracket 17 is connected. If desired, a spacer 62 can be located between the intermediate bracket 61 and the clamp bracket 17.

The intermediate bracket 61 includes an upper rearwardly facing surface 63 located in opposed spaced relation to the upper, forwardly facing surface 37 of the mounting bracket 33. In the illustrated construction, the rearwardly facing surface 63 includes two laterally spaced portions 65 and 67 formed by laterally extending wings 69. The intermediate bracket 61 also includes a lower forwardly facing surface 71 in rearwardly spaced and opposing relation to the lower rearwardly facing surface 35 of the mounting bracket 33. In the illustrated construction, lower surface 71 includes two laterally adjacent portions 73 and 75.

In further accordance with the invention, noise and vibration isolating means are provided for supporting the intermediate bracket from the mounting bracket. In the construction shown in FIGS. 1 through 5, such means comprises one or more upper isolators 77 extending between the upper forwardly facing surface 37 of the mounting bracket 33 and the upper rearwardly facing surface 63 of the intermediate bracket 61, together with one or more isolators 79 extending between the lower, rearwardly facing surface 35 of the mounting bracket 33 and the lower, forwardly facing surface 71 of the intermediate bracket 61.

While the upper and lower isolators 77 and 79 can provide sufficient vertical support for the intermediate bracket 61, it is preferred to provide the mounting bracket 33 with a lower rearwardly extending shelf 81 having an upwardly facing surface 83 and to provide the intermediate bracket 61 with a downwardly facing surface 85 in spaced and opposed relation to the upward facing surface 83 of the mounting bracket 33 and to locate between such

opposed surfaces

83 and 85 one or more isolators 87 which are particularly adapted to support vertical loading on the intermediate bracket 61.

In the construction shown in FIGS. 2 and 3, two upper isolators 77 and employed between the opposed portions 41-43 and 65-67 of the upper rearwardly and forwardly facing surfaces 37 and 63 and two lower isolators 79 are employed between the adjacent portions 36-38 and 73-75 of the lower forwardly and rearwardly facing surfaces and 71.

While various isolator constructions can be employed, in the construction shown in FIGS. 2 and 3, each of the upper and lower isolators 77 and 79 and the vertical load supporting isolator 87 comprises a com mercially available air bag comprising an inflatable disc-like rubber envelope 91 having opposed side faces to which are bonded mounting plates 93. Extending from the mounting plates 93 are threaded stubs 95 received in suitable holes in the adjacent brackets 36 and 61 and fixed thereto by nuts 97. Other means for attaching the air bags between the mounting bracket 33 and the intermediate bracket 61 can be employed. Each air bag is provided with a valve 99 facilitating inflation thereof and variation of the air pressure therein, whereby the operating characteristics of the mounting arrangements can be varied as may be desired. Al-

' though the various air bags could be associated with a common valve header, whereby uniform pressure could be provided in all of the bags, it is preferred to employ a separate valve 99 for each air bag to enhance adaptability of the mounting system to various load factors.

Illustrated in FIGS. 4 and 5 is another embodiment of an isolating system 111 in accordance with the invention. The isolating system 111 is substantially identical to the isolating system 11 except that the isolating system includes

isolators

177, 179 and 187 and mountings therefor which are of somewhat different form than the

isolators

77, 79 and 87 shown in FIGS. 2 and 3. The parts of the isolation system 111 (shown in FIGS. 4 and 5) which are substantially identical to the corresponding parts of the FIGS. 2 and 3 construction, have been given the same reference numerals as used in FIGS. 2 and 3.

Each of the

isolators

177, 179 and 187 incorporated in the construction shown in FIGS. 4 and 5 is commercially available and is made of soft rubber in the form of a channel having a web 201 and spaced extending flanges 203. Bonded to the outer extremities of the flanges 203 of each of the

soft rubber isolators

177, 179 and 187 is a mounting plate 205. The mounting plates 205 of the

isolators

177 and 179 are located on pedestals 207 and are connected to the bracket 33 by one or more bolts 2.09 extending through apertures in the pedestals 207 and in the adjacent surface of the mounting bracket 33 and secured thereto by nuts 211. The pedestals 207 merely serve to bridge the space between the opposed surfaces 35-71 and 37-63.

Bonded to the web of each of the

soft rubber isolators

177, 179 and 187 is a channel shaped mounting sleeve 213. The sleeves 213 bonded to the

isolators

177 and 179 capture the heads of one or more bolts 215 which pass through suitable apertures in the adjacent surface of the intermediate bracket 61 and are secured by respective nuts 217.

The mounting plate 205 of the vertical load supporting isolator 187 is bolted at 219 to a pedestal 221 which, in turn, is bolted at 223 to the downwardly facing surface 85 of the intermediate bracket 61.

The mounting sleeve 213 bonded to the web of the isolator 187 is connected by one or more bolts at 227 to the upwardly facing surface 83 of the mounting bracket 33.

Shown in FIG. 6 is a marine propulsion device in the form of an outboard motor 102 including a swivel bracket 104 and connected propulsion unit 106 including a power head 108 and a lower unit 110 which supports a propeller (not shown). The swivel bracket 104 is connected through a tilt pin 114 to a vertically extending bracket 116 which provides support for the tilt pin 114 and which in other respects corresponds to the before mentioned intermediate bracket 61. As in the embodiments shown in FIGS. 1 through 5, the tilt pin supporting bracket 116 is connected through a noise and vibration isolating system 118 to a mounting bracket 120 which is removably fixable in any suitable manner to a boat transom. The isolating system 118 is substantially identical to the isolating system shown in FIG. 1 through 3.

Shown fragmentarily in FIG. 7 a boat hull 148 including a bottom 150 and opposed sides 152. Structurally integrated into the boat hull 148, adjacent the rearward end thereof, is a structural member 156 which corresponds to the before mentioned mounting bracket 33 and which supports a rearwardly spaced member or bracket 158 which corresponds to the before mentioned intermediate bracket 61. As in the outboard motor 102 shown in FIG. 6, the rearwardly spaced bracket 158 is supported from the structural member 156 by an isolating system 160 such as disclosed in FIGS. 1 and 5.

Suitable means extend from the structural member 156 to the bottom 150 and sides 152 of the boat hull 148 to prevent entry of water into the boat hull. The structural member 156 can form the boat transom or, if desired. can be located forwardly of a false transom (not shown). In any event, the construction shown in FIG. 7 is intended to integrate the disclosed isolating system in a boat hull and to provide for removable attachment to the rear bracket 158 of a marine propulsion device such as an outboard motor 162.

As already indicated, when employing the isolating systems disclosed herein, the conventional isolation mounts employed in an outboard motor between the drive shaft housing and the king pin carried by the swivel bracket can be omitted if desired.

The use of isolators other than the air bags and rubber mounts which have been particularly described and illustrated, is also within the scope of the invention. Various of the features of the invention are set forth in the following claims.

I claim:

1. An outboard motor mounting arrangement comprising a mounting bracket adapted to be secured to the transom ofa boat and including a lower surface and an upper surface located in rearwardly spaced relation from and above said lower surface, an intermediate bracket located between said upper and lower surfaces of said mounting bracket and including an upper surface located in spaced facing relation to said upper surface of said mounting bracket and a lower surface in spaced facing relation to said lower surface of said mounting bracket, first and second discrete and laterally spaced noise and vibration isolating means extending between said spaced upper surfaces, and a third discrete noise and vibration isolating means extending between said spaced lower surfaces.

2. A mounting arrangement in accordance with claim 1 wherein said mounting bracket includes an upwardly facing surface, wherein said intermediate bracket includes a downwardly facing surface in opposed and spaced relation to said upwardly facing surface of said mounting bracket, and a fourth noise and vibration isolating means between said opposed upwardly and downwardly facing surfaces.

3. A mounting arrangement in accordance with claim 1 and further including a marine propulsion lower unit, and means connecting said lower unit to said intermediate bracket for vertical and horizontal swinging movement relative to said intermediate bracket.

4. A mounting arrangement in accordance with claim 1 wherein said third noise and vibration isolating means comprises two discrete mounts.

5. A mounting arrangement in accordance with claim 1 wherein each of said noise and vibration isolating means comprises an air bag.

6. A mounting arrangement in accordance with claim 5 wherein said air bags each include a rubber structure including a hollow interior and means for variably pressurizing said hollow interior of said rubber structure.

7. A mounting arrangement in accordance with claim 1 wherein each of said noise and vibration isolating means comprises a rubber mount.

8. A boat hull including bottom and sides extending from said bottom, a member connected to said boat hull adjacent to the rear thereof and including a lower surface and an upper surface located in rearwardly spaced relation from and above said lower surface, a bracket located between said upper and lower surfaces of said member and including an upper surface located in spaced facing relation to said upper surface of said member and a lower surface in spaced facing relation to said lower surface of said member, and first and second discrete, laterally spaced noise and vibration isolating means extending between said spaced upper surfaces, a third discrete noise and vibration isolating means extending between said spaced lower surfaces, and water-tight means extending between said member and said bottom and sides of said boat hull to prevent entry of water into said boat hull.

9. A boat hull in accordance with claim 8 wherein said member includes an upwardly facing surface, wherein said bracket includes a downwardly facing surface in opposed and spaced relation to said upwardly facing surface of said member, and a fourth noise and vibration isolating means between said opposed upwardly and downwardly facing surfaces.

10. A boat hull in accordance with claim 8 wherein said third noise and vibration isolating means comprises two discrete mounts.

11. A boat hull in accordance with claim 8 wherein each of said noise and vibration isolating means comprises an air bag.

12. A boat hull in accordance with claim 11 wherein said air bags each include a rubber structure including a hollow interior and means for variably pressurizing said hollow interior of said rubber structure.

13. A boat hull in accordance with claim 8 wherein each of said noise and vibration isolating means comprises a rubber mount.

14. An outboard motor comprising a mounting bracket removably and rigidly secured to the transom of a boat and including a lower surface and an upper surface located in rearwardly spaced relation from and above said lower surface, an intermediate bracket located between said upper and lower surfaces of said mounting bracket and including an upper surface located in spaced relation to said upper surface of said mounting bracket and a lower surface located in spaced relation to said lower surface of said mounting bracket, a first noise and vibration isolating means extending between said spaced upper surfaces, a second noise and vibration isolating means extending between said spaced lower surfaces, a tilt pin journalled by said intermediate bracket, a swivel bracket supported by said tilt pin for vertical swinging movement relative to said intermediate bracket, a propulsion unit, and a king pin connecting said swivel bracket to said propulsion unit to permit horizontal steering movement therebetween.

15. An outboard motor in accordance with claim 14 wherein said mounting bracket includes an upwardly facing surface, wherein said intermediate bracket includes a downwardly facing surface in opposed and spaced relation to said upwardly facing surface of said mounting bracket, and a third noise and vibration isolating means between said opposed upwardly and downwardly facing surfaces.

16. An outboard motor in accordance with claim 14 wherein each of said noise and vibration isolating means comprises two discrete mounts.

17. An outboard motor in accordance with claim 14 wherein each of said noise and vibration isolating means comprises an air bag.

18. An outboard motor in accordance with claim 17 wherein said air bags each include a rubber structure including a hollow interior and means for variably pressurizing said hollow interior of said rubber structure.

19. An outboard motor in accordance with claim 14 wherein each of said noise and vibration isolating means comprises a rubber mount.

* l l= l

Claims

1. An outboard motor mounting arrangement comprising a mounting bracket adapted to be secured to the transom of a boat and including a lower surface and an upper surface located in rearwardly spaced relation from and above said lower surface, an intermediate bracket located between said upper and lower surfaces of said mounting bracket and including an upper surface located in spaced facing relation to said upper surface of said mounting bracket and a lower surface in spaced facing relation to said lower surface of said mounting bracket, first and second discrete and laterally spaced noise and vibration isolating means extending between said spaced upper surfaces, and a third discrete noise and vibration isolating means extending between said spaced lower surfaces.