JPH0777878B2 - Air intake device for ship propulsion system - Google Patents

Description

Description of the Prior Art and Related Problems The outboard motor includes a cover designed to reduce the infiltration of water into the cylinder of the engine. As water,
Rain, water splashes, storms, etc. can be considered. Since the cover is usually lined with sound absorbing material, it also helps reduce sound.

Even if the water does not get into the engine, it can be a problem just because the water reaches the engine. This results in poor spark ignition and also leaves a corrosive precipitate as the salt water evaporates.
Everyone says that it is desirable not to put water. A blade and a deflector were arranged inside the opening at the air intake port. Under normal conditions, water still penetrates. This problem becomes more remarkable in a large engine that requires a large amount of combustion air. With this engine, it is necessary to provide a larger opening in the cover, so that water and noise become more serious problems.

The present invention is to overcome such problems.

The following prior art is noted: US Pat. Nos. 2,798,470, 3,195,530, and 3,610,198.
No. 2, No. 2,815,742, No. 3,204,619, No. 4,136,756,
2,839,042, 3,557,902, 4,326,660, 2,9
14,133, 3,712,416 and 4,379,702.

The present invention relates to an air intake device for an outboard motor, which includes an engine that drives a propeller. The motor cover comprises a lower pan-shaped cover and an upper dome-shaped cover that is hermetically coupled to the lower cover. Combustion air openings are provided in the upper portion of the cover. The baffle cooperates with the inside of this top cover to form a chamber.
The combustion air opening communicates with this chamber, and the partition between the opening and the chamber pushes the incoming air upwards into the chamber. The baffle plate cooperates with the upper cover to form a downward duct that guides air to the lower cover while avoiding the engine. Combustion air of the engine is sucked upward from the lower pan, and water taken in through the opening and moving down the duct is collected in the lower cover.

The present invention further provides a duct near the back of the cover,
On the other hand, air flows into the engine near the front surface of the cover.

Another feature is that in such a device, air holes are provided in the back surface of the cover and holes are also provided in the vicinity of the rear upper surface corners of the cover, and each of these holes has a partition inside the hole,
The partition plate is designed to return the water accumulated therein to the outside while the air flows upward to reach the chamber.

Yet another feature is the provision of means for draining water collected in the lower cover to the outside of the cover in such a device.

The present invention is not limited to the detailed configurations and arrangements of the parts described in the following description or shown in the drawings. The invention is capable of other aspects and of being practiced and carried out in various ways. For example, although the baffle plate is shown as being fixed to the cover, it may be located on the engine and configured to cooperate closely with the inside of the cover. Further, the terms and terms used in this specification are
It is for illustration purposes only and should not be considered limiting.

Practical example The outboard motor is equipped with a propeller 14 through a normal drive shaft and transmission device.
A power head 12 having a cover assembly 10 containing a motor for driving the. The spark plug 16 is on the back of the engine and the carburetor 18 is on the front of the engine. This is the normal arrangement. The cover assembly 10 comprises a lower pan-shaped cover 20 and an upper dome-shaped cover 22, which are hermetically joined at a seam 24. The upper cover includes an internal baffle plate 26 connected to the inside of the upper cover 22 and joined to the inside in a sealed state. As mentioned above, the baffle plate can be fixed to the engine by means of a suitable bracket or the like and can still be provided with all the features of the illustrated example in cooperation with the cover.

The inner baffle plate 26 cooperates with the inside of the upper cover to form an upper chamber, which can be referred to as a side chamber 28, at both corners of the upper back of the cover. These side chambers 28 span a central sloping partition plate 30 which, in cooperation with both sides of the baffle plate, forms a space for accommodating the flywheel of the engine. Side air opening
32 is open to this chamber 28. Aperture 32 has multiple vertical air holes
Immediately inside this air hole is an air baffle partition 36 that projects upward and inward. This partition has an opening 32
The air that flows upward into the opening is redirected downward by the dome-shaped cover to the duct formed by the downwardly projecting portion 40 of the baffle plate 26 and the rear surface 42 of the cover 22. Push up under the dome cover before pouring.

The cover 22 also includes a back opening 44 just above the duct 38. Air entering this opening must turn around the chimney portion 46 of the cover and must rise and pass through the opening 48 in the partition 50 that is part of the insert 52. The partition 50 also has a central opening 54, which allows the back opening 44 and the opening
Air entering 48 can pass through it downwards in the chimney 46 and into the duct 38.

In this way, the air entering each side opening is deflected upward and enters the side chamber between the baffle plate and the cover. This air then flows down into the duct 38 which continues down the back of the cover. Air entering the upper rear opening 44 in the cover is pulled up into the opening 48 surrounding the chimney 46,
It can then be turned through the opening 54 into the chimney 46,
It flows into the air between the baffle plate and the cover and enters the downwardly directed duct 38. Duct 38 directs air downward between the spark plugs 16, 16 on either side of the engine. Duct 38
Open into the lower pan-shaped cover 20 at the back of the cover assembly. Then the combustion air rises to the front of the cover,
It flows into a carburetor 18 which communicates with the engine cylinder.

Air entering the back or side openings must flow upwards to reach the central chamber between the baffle and the cover. Water that is blown up by the wind while riding on the wind will be thrown out by changing direction. In the case of side openings, the water thus deposited is then separated by the partition 36
To be reversed from the opening 32. Water entering the back opening must rise plate 50 and then redirect downwards back into the chimney. Therefore, water is more likely to deposit on the outside of the chimney and then recedes and flows out of the opening. Upon entering the interior side between the cover and the baffle, air is forced to flow down along the back of the cover and away from the spark plug and the engine itself. Therefore, the incoming water is
Does not wet the outside of the mover. The water changes its direction at the bottom of the duct 38 and flows forward, and the water on the air is more likely to be thrown out of the air stream again, and collects on the bottom surface 56 of the lower pan-shaped cover 20. The air flows forward, diverts to information (releasing more water) to vaporizer 18 and into the engine. All of this water collects at the bottom of the pan cover and can be drained by a pump 58 actuated by an inhaler, or it can be drained by a suitable one or check valve device.

The inner surface of the dome-shaped cover 22 is lined with a soundproof or sound absorbing material such as foam. Labyrinth or convoluted airflow passages are also suitable for imparting convolution to the transmission of sound. Therefore, the volume outside the motor cover is lower than that of a motor having a normal opening without such a baffle plate device. This device significantly reduces the volume.

By means of the baffle, the water which has been carried in the air flow or which has been blown into the opening towards the cover is first displaced upwards even before reaching the interior of the cover. Water passing through this diversion is redirected again to flow down to the bottom of the cover assembly and set back, while the air continues to move forward and then rises to the carburetor. With each turn, the water runs off and this water is then discharged to the outside of the cover. As described above, according to the present invention, the duct extending along the rear portion of the upper cover member is opened near the lower cover member, and the combustion air is provided at a position close to the front portion of the upper cover member. Since the engine is allowed to enter the lower cover member, the combustion air that has passed through the duct changes its direction to the front side of the upper cover member near the lower cover member in the rear part of the upper cover member. At the same time, since the direction is changed to the engine side on the lower cover member and in the position close to the front portion of the upper cover member, the combustion air is introduced into the engine after being introduced into the cover surrounding the engine. The flow direction will be changed at least twice until it reaches, and the water content contained in the combustion air can be surely removed.

Further, since the duct is arranged along the rear portion of the upper cover member, the duct is arranged at a position distant from the hull. It is less affected by the generated noise.

[Brief description of drawings]

FIG. 1 is a side view of an outboard motor schematically showing a side air intake of a motor cover and a baffle plate device inside the cover. FIG. 2 is a partially cutaway vertical sectional view showing various features of the baffle plate device. FIG. 3 is a rear view of the upper part of the power head of the outboard motor, in which a part of the notch and the other part of the flow of air to the engine are shown by dotted lines. FIG. 4 is a horizontal sectional view taken along the line 4-4 in FIG. FIG. 5 is a horizontal sectional view taken along the line 5-5 in FIG. FIG. 6 is an enlarged perspective view of an internal baffle plate device having a cover and an inlet, in which the cover is shown by a chain line to show the relationship between each part and the air flow path. 10 …… Cover assembly 12 …… Power head 14 …… Propeller 16 …… Spark plug 18 …… Vaporizer 20 …… Lower pan cover 22 …… Upper dome cover 24 …… Seam 26 …… Baffle plate 28 …… Side chamber 30 …… Partition plate 32 …… Air opening 34 …… Air hole 36 …… Air deflector partition 38 …… Duct 40 …… Projection part of the baffle plate 42 …… Back side of cover 44 …… Back opening 46 …… Chimney of cover 48 …… Opening 50 …… Partition 52 …… Insert 54 …… Center opening 56 …… Bottom of bottom cover 58 …… Pump.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-57-26091 (JP, A) Actually opened 60-95293 (JP, U) Actually opened 57-32600 (JP, U) Actual public 58- 26238 (JP, Y2)

Claims (7)

[Claims] 1. An air intake device for a marine propulsion device having an engine for driving a propeller having a top portion, wherein the air intake device includes a cover surrounding the engine, and the cover has a pan shape. A lower cover member and a dome-shaped upper cover member hermetically coupled to the lower cover member, the upper cover member having an opening for a front portion, a rear portion, and combustion air. A portion of the air enters the engine at a position proximate the front portion of the upper cover member, and most or all of the air enters the engine on the lower cover member; The cover member includes a baffle plate that cooperates with the upper cover member to form a downwardly directed duct, and the duct communicates with the opening and extends from the engine. Separated in a horizontal direction, the duct extends along the rear portion of the upper cover member, opens near the lower cover member, and extends substantially below the top of the engine, The duct guides air from the opening toward the lower cover member along the rear portion of the upper cover member in a state of being separated from the engine, and the water taken in into the air and flowing in the lower side is the lower side. An air intake device stored in a cover to prevent wetting of the engine and for combustion air to be drawn into the engine from the lower cover member. 2. The baffle plate cooperates with the upper cover member to form a chamber communicating between the opening and the duct, and the air intake device is close to the opening. 2. The air intake device according to claim 1, further comprising a partition wall that is disposed as a unit and has a wall means that extends above the opening and directs air that enters the chamber from the opening upward. 3. The air intake device of claim 2, wherein the opening is located at the rear portion of the cover. 4. The cover has an upper rear corner and the inflator further comprises additional openings proximate to each of the upper rear corners of the cover, all of the additional openings. The air intake device according to claim 3, which is in communication between a chamber and the duct. 5. The upper cover member has a pair of upper rear corners, one of the upper rear corners having the opening,
The other of the upper rear corners is provided with an additional opening, the upper cover member is further provided with a pair of partition walls provided corresponding to the openings respectively, and the duct is downwardly extended from the chamber to the upper cover. The air intake device of claim 2, wherein the engine extends along the rear portion of the member and the engine draws in combustion air from near the front portion of the upper cover member. 6. The duct guides the water entering the chamber downward toward the lower cover member, and the air intake device discharges the water collected in the lower cover member to the outside of the cover. An air intake device according to claim 5, further comprising means for: 7. The partition wall is adapted to direct water entering the opening back to the outside of the cover.
Air intake device as described.