JP2995913B2 - Engine cover seal structure for outboard motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cover seal structure for an outboard motor.

[0002]

2. Description of the Related Art In a general outboard motor, a substantially flat intermediate member called an engine holder is mounted on an uppermost portion of a casing, and an engine is mounted on the engine holder in a posture in which a crankshaft is erected. doing.

[0003] The engine is covered with an engine cover and is waterproofed. Usually this engine cover is
The lower cover is fixed to the outboard motor and covers the lower part of the engine, and the upper cover is detachably mounted on the lower cover and covers the upper part of the engine.

Conventionally, the inner peripheral seal portion of the lower cover (the portion through which the body of the outboard motor passes) is provided around the engine holder or around a holding plate interposed between the engine holder and the engine. Contacted through
A seal was provided between the outboard motor and the lower cover to prevent water from entering from below the lower cover.

[0005]

However, since a clamp bracket for mounting the outboard motor on the hull is pivotally attached to the engine holder, the inner peripheral portion of the lower cover is brought into contact with the periphery of the engine holder to seal the engine. To avoid this, it is necessary to avoid the pivot portion of the clamp bracket, which is difficult in terms of layout, and may impair the waterproofness between the lower cover and the engine holder.

Further, a method of installing a holding plate between the engine holder and the engine and abutting the lower cover to seal the parts increases the number of parts and costs, and the engine is a four-cycle engine. In such a case, the oil pan provided at the lower part of the engine holder communicates with the engine, so it is difficult to interpose another member such as the holding plate between the engine and the engine holder.

Further, in an outboard motor equipped with a large engine, which has been increasing in recent years, it is necessary to mount the engine at a lower position with respect to the hull in order to reduce the center of gravity, and the position of the clamp bracket is higher than the engine. Has a tendency to rush. For this reason, it is necessary to avoid the clamp bracket by providing a step or gradient rising upward on the bottom surface of the lower cover.However, in the conventional method of sealing by contacting the inner peripheral seal portion of the lower cover with an engine holder, etc. Since the thickness of the holder is thin, it is impossible to provide the above-mentioned steps or gradients, and it has not been possible to contribute to lowering the center of gravity of the outboard motor.

The present invention has been made in view of the above problems, and has a complicated ship by providing a simple seal structure on the inner periphery of the lower cover, having a high waterproof effect, and forming a step or a gradient on the bottom surface of the lower cover. An object of the present invention is to provide an engine cover seal structure for an outboard motor that can conform to the shape of the outer motor.

[0009]

To achieve the above object, an engine cover seal structure for an outboard motor according to the present invention includes a lower cover fixed to an engine holder of the outboard motor and covering a lower portion of the engine; An engine cover seal structure for an outboard motor comprising an upper cover detachably mounted on an upper cover to cover an upper portion of an engine, wherein an outer flange is formed at a lower portion of the engine over the entire outer peripheral surface thereof, and The lower cover is supported on an apron that covers the periphery of the engine, while the lower cover is integrally provided with an inner peripheral seal portion on an inner flange fixed to an engine holder. The lower surface of the flange is pressed against the upper surface of the inner peripheral seal portion of the lower cover via a sealing material.

[0010]

By configuring the engine cover seal structure of the outboard motor as described above, the engine is brought into close contact with the lower cover and the two are sealed, so that a separate sealing member is not required.

Further, a step or a gradient is provided on the bottom surface of the lower cover, so that it is possible to cope with a complicated outboard motor shape.

[0012]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a right side view of an outboard motor having an engine cover seal structure for an outboard motor according to the present invention.

The outboard motor 1 has an engine 5 mounted on a substantially flat engine holder 3 mounted on the uppermost portion of a casing 2 in a posture in which a crankshaft 4 is upright.
A general layout in which the output of the engine 5 is transmitted to a propeller shaft 8 via a drive shaft 6 suspended in the casing 2 and a forward / reverse switching device 7 to drive the propeller 9 forward or reverse. With

In this embodiment, the engine 5 is a large four-stroke gasoline engine, and has an oil pan 10. The oil pan 10 is provided on the lower surface of the engine holder 3 and is configured to enter the casing 2.

The engine 5 is covered with an engine cover 11 made of a synthetic resin material or the like, and is waterproofed. The engine cover 11 includes a lower cover 12 fixed to the outboard motor 1 and covering a lower portion of the engine 5, and an upper cover 13 detachably mounted on the lower cover 12 and covering an upper portion of the engine 5.

An apron 14 formed of a synthetic resin material or the like is provided around the upper portion of the casing 2 similarly to the engine cover 11. The apron 14 supports the lower cover 12 from below, covers the periphery of the engine holder 3, improves the appearance of the outboard motor 1, and temporarily prevents flooding from below the lower cover 12. .

The outboard motor 1 has a clamp bracket 1 pivotally attached to a casing 2 and an engine holder 3.
The hull 16 is installed so as to be rotatable left and right with respect to the hull 16 via the steering wheel 5, and the hull 16 is steered while being propelled.

FIG. 1 is a longitudinal sectional view of an engine cover 11 showing one embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG.

The lower cover 12 is mounted on the engine holder 3.
Is fixed to the upper surface by several bolts 17. The lower peripheral portion of the lower cover 12 is supported by the upper edge of the apron 14 fixed to the casing 2.

The upper cover 13 is in close contact with the lower cover 12 via a packing 18 made of an elastic material such as rubber, and is detachably attached with a single touch by a lock mechanism (not shown).

On the other hand, an outer flange 19 is formed all around the lower outer peripheral surface of the engine 5. As shown in FIG. 3, which is a bottom view of the engine 15, the outer flange 19 is formed across the cylinder head 5a, the cylinder block 5b, and the oil pump 5c that constitute the engine 5, and the above-described components 5a , 5b and 5c are integrally formed at the time of casting. The hatched portion in FIG. 3 is a raised surface where the engine 5 is in close contact with the engine holder 3, and has a bolt hole 20 for fixing the engine 5 to the engine holder 3.

The outer flange 19 is covered with a sealing material 21 made of an elastic material such as rubber, and the engine holder 3 holding the engine 5 is covered with an apron 14 as shown in FIG. Is done. When the engine 5 is mounted on the outboard motor 1, the lower surface of the outer flange 19 is pressed against the upper surface of the inner peripheral seal portion 12 a of the lower cover 12 via the sealing material 21.
As shown in FIGS. 1 and 2, the lower cover 12 has an inner flange extending at the bottom, and an inner peripheral seal portion 12a is integrally formed inside the inner flange. Therefore, the sealing member 21 and the bolt 17 are not exposed to the outside, and the external shape can be improved.

Therefore, the space between the engine 5 and the inner peripheral seal portion 12a of the lower cover 12 is completely sealed, and the inside of the engine cover 11 is waterproofed.

In such a sealing structure, the lower cover 1
Since there is no need to prepare a separate member for sealing between the engine 2 and the engine 5, the structure is simple, and an oil pan and an oil pump are installed below the engine as in a four-stroke engine, resulting in a complicated structure. In this case, a complete sealing effect can be expected. Since the outer flange 19 provided on the engine 5 is integrally formed at the time of casting the cylinder head 5a, the cylinder block 5b, and the oil pump 5c, there is no increase in cost.

Further, by applying the engine cover seal structure for an outboard motor according to the present invention, it is possible to provide a step or a gradient on the bottom surface (inner flange) of the lower cover 12. As shown in FIG. 1, the outer flange 19 of the engine 5 is similarly provided with a step or a gradient according to the step or the gradient of the bottom surface of the lower cover 12. The step 22 provided in the present embodiment is for raising the bottom surface of the lower cover 12 forward.
The engine 5 can be installed by being lifted upward, and the engine 5 is positioned relatively lower than the hull 16, which can contribute to lowering the center of gravity of the outboard motor 1.

[0027]

As described above, the engine cover seal structure for an outboard motor according to the present invention includes a lower cover fixed to an engine holder of the outboard motor and covering a lower portion of the engine.
In the seal structure of an engine cover of an outboard motor comprising an upper cover detachably mounted on the lower cover and covering an upper part of the engine, an outer flange is formed at the lower part of the engine over the entire outer peripheral surface thereof, While the lower cover is supported on an apron covering the periphery of the engine holder, the lower cover is integrally provided with an inner peripheral seal portion on an inner flange fixed to the engine holder, and when the engine is mounted on the outboard motor, The lower surface of the outer flange is pressed against the upper surface of the inner peripheral seal portion of the lower cover via a sealing material.

Therefore, the fastening portion between the engine holder and the lower cover and the sealing material are not exposed to the outside, and the sealing material is hardly deteriorated or damaged due to the surrounding environment. The sealing is performed by the inner peripheral sealing portion of the lower cover. It is possible to maintain and improve the sealing function effectively, but it is not necessary to use a separate member to seal between the lower cover and the outboard motor. Since the lower surface of the outer flange of the engine is pressed by the weight of the engine via the sealing material, the seal structure is simple and the waterproof effect is high. Further, the engine holder is covered with an apron, so that the appearance of the outboard motor is improved, and the appearance can be made smart and small in ventilation resistance.

Further, since a step or a gradient can be freely provided on the bottom surface of the lower cover, it is possible to cope with a complicated outboard motor shape.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an engine cover showing one embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a bottom view of the engine as viewed from an arrow III in FIG. 1;

FIG. 4 is a right side view of the outboard motor provided with the engine cover seal structure of the outboard motor according to the present invention.

[Explanation of symbols]

 2 Casing 3 Engine Holder 5 Engine 11 Engine Cover 12 Lower Cover 12a Inner Seal 13 Upper Cover 14 Apron 15 Clamp Bracket 16 Hull 19 Outer Flange 21 Sealing Material 22 Step

Claims (1)

(57) [Claims] 1. A seal for an engine cover of an outboard motor, comprising: a lower cover fixed to an engine holder of the outboard motor and covering a lower portion of the engine; and an upper cover detachably mounted on the lower cover and covering an upper portion of the engine. In the structure, an outer flange is formed at the lower portion of the engine over the entire outer peripheral surface thereof, and the lower cover is supported on an apron covering the periphery of the engine holder, while the lower cover is fixed to the engine holder by an inner flange. The lower surface of the outer flange of the engine is pressed against the upper surface of the inner peripheral seal portion of the lower cover via a sealing material when the engine is mounted on the outboard motor. An engine cover seal structure for an outboard motor.