Cowling assembly for outboard motor

Abstract

A cowling assembly for covering an internal combustion engine of an outboard motor includes a bottom cowling, with a bottom-side hook, attached to an opening edge of the bottom cowling. The cowling assembly further includes a top cowling, and a top-side hook, attached to an opening edge of the top cowling is engageable with the bottom-side hook. A mounting boss is additionally secured to an inner side of the opening edge of the top cowling, and the top-side hook is attached to the mounting boss.

Description

PRIORITY INFORMATION

The present application is based on and claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2004-024892, filed on Jan. 30, 2004, the entire contents of which are expressly incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a cowling assembly for an outboard motor having top and bottom cowling members for covering an internal combustion engine.

2. Description of the Related Art

Conventionally, outboard motors include internal combustion engines covered with top and bottom cowlings. The top and bottom cowlings often attach to one another by engaging bottom-side hooks attached to the opening edge of the bottom cowling and top-side hooks attached to the opening edge of the top cowling. For example, Japanese patent JP2002349257A2, entitled OUTBOARD MOTOR, discloses such an arrangement.

SUMMARY OF THE INVENTION

An aspect of at least one invention described herein includes the realization that when hook mounting bosses for securing the top-side hooks are formed integrally with the top cowling by molding, the top cowling can be excessively thick in the area of the molding. The top cowling is thus heavier, especially when the top cowling is made of a reinforced resin, as is frequently the case. To address such a need, an aspect of at least one invention described herein involves providing a cowling assembly with a top cowling formed of lighter weight material such that the top cowling is strong enough to support hook mounting bosses for securing the top-side hooks and further is strong enough around an opening edge of the top cowling to suitably engage and seal with the bottom cowling.

Another aspect of at least one invention described herein includes the realization that although mounting bosses for securing top-side hooks can be formed separately from the top cowling and can then be attached to the top cowling, the joints of such separately formed bosses are usually at least partially exposed to the outside of the top cowling, which adversely affects the appearance of the outboard motor.

Thus, in accordance with an embodiment, a cowling assembly for an outboard motor, comprising a top cowling and a bottom cowling for covering an internal combustion engine of the outboard motor is provided. The cowling assembly comprises a bottom-side hook attached to an opening edge of the bottom cowling. A top-side hook is attached to an opening edge of the top cowling and engageable with the bottom-side hook. Additionally, a mounting boss is secured to an inner side of the opening edge of the top cowling, wherein the top-side hook is attached to the mounting boss.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention are described below with reference to the drawings of preferred embodiments, which embodiments are intended to illustrate and not to limit the present invention.

FIG. 1 is a side view of one embodiment of an outboard motor, having top and bottom cowling members and with certain internal components illustrated in phantom line.

FIG. 2 is a top plan view of the outboard motor of FIG. 1 with a top cowling member removed and an engine illustrated in phantom line.

FIG. 3 is a side elevational and partial cut-away view of the top cowling member of FIG. 1 removed from the outboard motor, and illustrating a top-side attaching part of the top cowling member.

FIG. 4 is a bottom plan view of the top cowling member removed from the outboard motor.

FIG. 5 is an enlarged top plan view of a bottom-side attaching part connected to the bottom cowling member.

FIG. 6 is a cross-sectional view of FIG. 5 taken along the VI-VI line.

FIG. 7 is a cross-sectional view of FIG. 5 taken along the VI-VII line.

FIG. 8 is an elevational view of a top-side hook attached to the top cowling.

FIG. 9 is a partial sectional view illustrating the attached state of the top cowling and an annular rail according to an embodiment.

FIG. 10 is another partial sectional view illustrating the attached state of the top cowling and the bottom cowling.

FIG. 11 is partial sectional view of a seal formed between the top cowling and the bottom cowling according to an embodiment of at least one invention described herein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1-11 illustrate a cowling assembly 7 for an outboard motor 1 configured in accordance with certain features, aspects, and advantages of at least one invention described herein. The outboard motor 1 merely exemplifies one type of outboard drive. However, the various cowling assemblies disclosed herein can be used with other types of devices that benefit from cowling types of enclosures. Such applications will be apparent to those of ordinary skill in the art in view of the description herein. These inventions are not limited to the embodiments described, which include the preferred embodiments, and the terminology used herein is not intended to limit the scope of the present inventions.

The general structure of an outboard motor is described with reference to FIG. 1. As depicted in FIG. 1, an outboard motor 1 is attached to a stem plate 100a of a hull 100 of a boat or other watercraft by a clamp bracket 2. A swivel bracket 5, having upper and lower damper members 3 for elastically supporting a propulsion unit 4, is supported for vertical rotation by a cramp bracket 2 via a tilt shaft 6.

The propulsion unit 4 has a housing comprising a cowling assembly 7, an upper case 8, and a lower case 9. An internal combustion engine 10, such as, for example, a four-cycle internal combustion engine, can be housed in the cowling assembly 7. However, other engines can also be used. In various embodiments, the upper case 8 is attached to a lower part of an exhaust guide plate 11. The internal combustion engine 10 can be supported on the exhaust guide 11 plate.

As depicted in FIG. 1, the internal combustion engine 10 has a crankshaft 12 extending vertically and connected to an upper end of a drive shaft 13, which extends vertically through the upper case 8. A lower end of the drive shaft 13 is connected to a forward/reverse switching mechanism 14 housed in the lower case 9. A propeller shaft 15 extends horizontally from the forward/reverse switching mechanism 14 and has a rear end, which protrudes outside of the lower case 9, and to which a propeller 16 is attached.

The cowling assembly 7 can comprise a bottom cowling member 20 and a top cowling member 40 that, in various embodiments, attach to one another, described in greater detail below with reference to FIGS. 2 to FIG. 10.

FIG. 2 is a plan view of one embodiment of the bottom cowling 20, with the internal combustion engine 10 illustrated in phantom line. The bottom cowling 20 can be made of an aluminum material by die-casting, or any other method.

The bottom cowling 20 has an opening edge 20a, from which a rib 20a1 extends upwards, also shown in another perspective in FIG. 7. The rib 20a1 can be configured to form a seal between the bottom cowling 20 and the top cowling 40, also described below with reference to FIG. 10.

Bottom-side attachment assemblies 21 can be provided at a plurality of positions along the opening edge 20a of the bottom cowling 20. For example, in the embodiment depicted in FIG. 2, bottom-side attachment assemblies 21 are provided at three positions along the opening edge 20a of the bottom cowling 20, namely, at a position that faces the hull 100 and at positions on the port and starboard sides of the bottom cowling 20.

FIG. 5 is a plan view of one embodiment of a bottom-side attaching part, and FIGS. 6 and 7 are cross-sectional views of FIG. 5, taken along the lines VI-VI and VII-VII, respectively. Each of the bottom-side attachment assemblies 21 comprises a supporting holder 22, a bottom-side hook 23, a mounting bolt 24, a spring 25, and a lever 26. The supporting holder 22 is secured to a mounting boss 20b extending inward from the opening edge 20a of the bottom cowling 20 by mounting bolts 27. The bottom-side hook 23 is attached, by the mounting bolt 24, to a supporting shaft 28 rotatably supported by the supporting holder 22. A stay 29 is attached to the mounting boss 20b by a mounting bolt 30, and the spring 25 is provided between the stay 29 and a supporting part 23a of the bottom-side hook 23. The spring 25 is urged in a direction to raise an engaging part 23b of the bottom-side hook 23 that is attached to the opening edge 20a of the bottom cowling 20. The supporting holder 22 has a positioning recess 22a. As depicted in FIG. 7, the bottom cowling 20 further comprises a seal member 50, which includes an engaging part 50a and a seal part 50b, and whose function will be described in greater detail with respect to the attachment of the top cowling 40 and the bottom cowling 20.

FIGS. 3 and 4 provide two views of an embodiment of a top cowling 40. FIG. 3 is a side view of the top cowling member 40, from which an exterior part is cut away to reveal a top-side attachment assembly 43 inside the top cowling member 40. The top-side attachment assembly 43 is described in greater detail below.

FIG. 4 is bottom plan view of one embodiment of the top cowling 40. The top cowling 40 can be provided with a baffle plate 41 covering an intake opening 42 of the top cowling 40. The baffle plate 41 can include a pair of right and left air intake openings 41a. Air introduced through the intake opening 42 and sucked through the air intake openings 41a can be used to cool the engine 10. The air can also be sucked through an air cleaner (not shown) and then into the engine 10 for combustion therein. Water drops separated by the baffle plate 41 are collected into a discharge hose 49 and can be discharged so as not to fall onto the engine 10.

In various embodiments, the top cowling 40 is made by pressing a nonferrous material into a desired shape. For example, the top cowling 40 can be formed by pressing a plate of a nonferrous metal, such as aluminum or magnesium. When the top cowling is formed by pressing a nonferrous material, the top cowling can be thin as compared with ones produced by the methods using other metal. Also, the top cowling can be recyclable and can largely contribute to the weight reduction of the outboard motor. Furthermore, since the top cowling can be formed without burring and buff finishing used for casting products, the appearance quality can be improved and the number of steps in the production process can be reduced.

As further depicted in FIGS. 3 and 4, the top cowling 40 has an opening edge 40a. The opening edge 40a of the top cowling 40 has an inner side 40a1.

With reference to FIGS. 8-10, each of the top-side attaching parts 43 comprises a mounting boss 44, a top-side hook 45, and a mounting bolt 46. In various embodiments, the mounting bosses 44 are secured by one or more of a variety of methods. For example, the mounting bosses 44 can be secured with an adhesive, which allows the mounting bosses 44 to be secured easily and firmly. The mounting bosses 44 can also be secured by welding or by another method.

An annular rail 80 is attached to the mounting bosses 44 by mounting bolts. In a preferred embodiment, the annular rail 80 is formed by curving an elongated metal strip into a shape which fits the inner periphery of the opening edge 40a. For example, the annular rail 80 can be formed by stamping a large metal plate material into a shape which fits the inner periphery of the opening edge 40a. However, other manufacturing techniques can also be used.

As depicted in FIGS. 9 and 11, a ridge 80a is formed on one of the upper and lower sides of the annular rail 80 to increase the strength of the annular rail 80. In the embodiments depicted in FIGS. 9 and 11, the ridge 80a is formed the upper side of the annular rail 80. The ridge 80a can alternatively be formed on the lower side of the annular rail 80, or the annular rail 80 can have ridges on both sides. The annular rail 80 can be formed of a flat plate or formed by laminating a plurality of plates. In some embodiments, a metal, such as iron or SUS, is used as the material for forming the annular rail 80. In other embodiments, the annular rail 80 can be made from aluminum or another material.

As further shown in FIGS. 9 and 11, an attaching surface 80b of the annular rail 80 can be secured to the inner side 40a1 of the opening edge 40a of the top cowling 40 with an adhesive. Additionally, mounting bosses 44 formed on the annular rail 80 can be used to secure the annular rail 80 to the top cowling 40. More specifically, attaching surfaces 441 of the mounting bosses 44 can be secured to the inner side 40a1 of the opening edge 40a of the top cowling 40 with an adhesive. Thus, the annular rail 80 can be attached to the top cowling 40 easily and firmly.

Advantages of securing the attaching surfaces 80b and 441 of the annular rail 80 to the inner side 40a1 of the opening edge 40a of the top cowling 40 include the resulting reinforcement of the opening edge 40a and the enhanced mounting strength of the top cowling 40.

In various embodiments, top-side attachment assemblies 43 are provided at a plurality of positions around the top cowling 40. In a preferred embodiment, depicted in FIG. 4, top-side attachment assemblies 43 are provided at three positions, namely, on a side of the top cowling 40 that faces the hull 100 and positions on two opposing sides of the top cowling 40.

The top-side hooks 45 are secured to the mounting bosses 44 by the mounting bolts 46. Since the top-side hooks 45 are attached to the mounting bosses 44, which in turn are secured to the inside of the top cowling 40, components of the top-side attaching parts 43 are not exposed to the outside of the top cowling 40 and thus are protected from moisture, and the quality of appearance of the outboard motor is thus enhanced. Furthermore, the mounting bosses thus serve as reinforcement and improve the mounting strength of the top cowling. Also, the improved structure can contribute to the weight reduction of the outboard motor.

Each of the mounting bosses 44 has a positioning damper 47. A leg member 81 is attached to each of the mounting bosses 44 such that it extends beyond the opening edge 40a of the top cowling 40. The leg members 81 can be attached easily and firmly using the mounting bosses 44.

Referring now to FIG. 10, the top cowling 40 and the bottom cowling 20 are shown in a state of attachment to one another. According to a preferred embodiment, to close the top cowling 40, engaging parts 45a of the top-side hooks 45 are pressed against the engaging parts 23b of the bottom-side hooks 23, thereby rotating the bottom-side hooks 23 against the springs 25. After the engaging parts 45a of the top-side hooks 45 have passed, the engaging parts 23b of the bottom-side hooks 23 are rotated by the springs 25 in the opposite direction to the original positions with the engaging parts 45a of the top-side hooks 45 below them, and the attached state shown in FIG. 10 is established.

As further depicted in FIG. 10, each of the mounting bosses 44 has a positioning damper 47. When the top cowling 40 and the bottom cowling 20 are attached to each other, the positioning dampers 47 of the top-side attaching parts 43 are engaged with the positioning recesses 22a of the bottom-side attaching parts 21 to position the top cowling 40 and the bottom cowling 20 in a vertical direction.

When the top cowling 40 and the bottom cowling 20 are attached to one another, the seal member 50 provides a seal between the top cowling 40 and the bottom cowling 20 as shown in FIG. 11. The seal member 50 comprises an engaging part 50aand a seal part 50b. The seal member 50 can be attached to the bottom cowling 20 by engaging the engaging part 50a with the annular rib 20a1 along the opening edge 20a of the bottom cowling 20, while the seal part 50b of the seal member 50 extends all along the opening edge 20a.

When the top cowling 40 and the bottom cowling 20 are attached to one another, the seal part 50b is compressed between a lower side of the annular rail 80 and the inner side 40a1 of the opening edge 40a to provide a seal. In this embodiment, since a seal is formed by sealing surfaces extending in different directions, namely the annular rib 20a1 formed along the opening edge 20a of the bottom cowling 20, the inner side 40a1 of the opening edge 40a, and the annular rail 80 of the top cowling 40, a strong and effective seal can be formed.

Although this invention has been disclosed in the context of certain preferred embodiments, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments can be made and still fall within the scope of the invention. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.

Claims

1. A cowling assembly for an outboard motor, comprising a top cowling and a bottom cowling for covering an internal combustion engine of the outboard motor, said cowling assembly comprising:

a bottom-side hook attached to an opening edge of the bottom cowling;

a top-side hook attached to an opening edge of the top cowling and engageable with the bottom-side hook; and

a mounting boss secured to an inner side of the opening edge of the top cowling, wherein the top-side hook is attached to the mounting boss.

2. The cowling assembly for an outboard motor of claim 1, wherein the mounting boss is secured to the inner side of the opening edge of the top cowling with an adhesive.

3. The cowling assembly for an outboard motor of claim 1, wherein a leg member extending beyond the opening edge of the top cowling is attached to the mounting boss.

4. The cowling assembly for an outboard motor of claim 2, wherein a leg member extending beyond the opening edge of the top cowling is attached to the mounting boss.

5. The cowling assembly for an outboard motor of claim 1, wherein a positioning damper is attached to the mounting boss.

6. The cowling assembly for an outboard motor of claim 2, wherein a positioning damper is attached to the mounting boss.

7. The cowling assembly for an outboard motor of claim 3, wherein a positioning damper is attached to the mounting boss.

8. The cowling assembly for an outboard motor of claim 1, wherein the top cowling is formed by pressing a nonferrous material.

9. The cowling assembly for an outboard motor of claim 3, wherein the top cowling is formed by pressing a nonferrous material.

10. The cowling assembly for an outboard motor of claim 5, wherein the top cowling is formed by pressing a nonferrous material.