JP3497497B2 - Outboard exhaust gas sampling system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas sampling device for an outboard motor that collects engine exhaust gas through an exhaust gas sampling pipe.

[0002]

2. Description of the Related Art In order to analyze harmful components contained in exhaust gas discharged from an engine of an outboard motor, sample exhaust gas is sampled from an exhaust gas sampling pipe provided in the exhaust passage, and a component measuring instrument is used. It is being analyzed. As an exhaust gas sampling device for such an outboard motor, Japanese Patent Laid-Open No. 4-1664
The one described in Japanese Patent Publication No. 95 is conventionally known.

[0003]

By the way, the exhaust gas sampling pipe of the above-mentioned conventional exhaust gas sampling device is screwed into the exhaust pipe and fixed by a lock nut, and penetrates the outer wall surface of the outboard motor. The opening exposed to the outside is closed with a plug. When collecting the exhaust gas, the plug is removed and the exhaust gas component measuring device is connected.

However, in the above-mentioned conventional exhaust gas sampling device for an outboard motor, since the tip of the exhaust gas sampling pipe is exposed to the outside from the outer wall of the outboard motor, salt is attached when sea water is splashed. There is a possibility that the work of removing the plug may be hindered due to rusting, or that it may be caught on another article during transportation.

In the above outboard motor, the engine including the exhaust gas sampling pipe can be easily attached and detached, the exhaust pipe can be efficiently cooled, and the exhaust gas sampling pipe can be firmly fixed and supported. Is required.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide an exhaust gas sampling apparatus for an outboard motor, which can satisfy the above-mentioned requirements and can solve the above-mentioned conventional problems.

[0007]

In order to achieve the above-mentioned object, the present invention provides an engine, a propeller driven by the engine, a case means for rotatably supporting the propeller, and a detachable case means. An engine cover that is freely provided and covers the engine from above, an exhaust pipe that extends downward from the engine so as to guide the exhaust gas from the exhaust port of the engine to the lower part of the internal space of the case means, and this exhaust pipe An exhaust gas sampling device for an outboard motor, comprising: an exhaust gas sampling pipe connected to the exhaust pipe; the exhaust pipe covering the exhaust pipe so as to form a cooling water passage between the exhaust pipe and the outer periphery thereof. The first feature is that the exhaust pipe cover is divided into two parts and the exhaust gas sampling pipe is sandwiched by the mating surfaces of the exhaust pipe cover.

In addition to the above-mentioned first feature, the present invention also provides:
A tip portion of the exhaust gas sampling pipe is extended into an engine room defined by the case means and the engine cover, and the tip portion of the exhaust gas sampling pipe has a tip thereof.
A second feature is that a plug for closing the opening at the end is detachably attached .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below based on the embodiments of the present invention illustrated in the accompanying drawings.

1 to 6 show an embodiment of the present invention. FIG. 1 is an overall side view of an outboard motor, FIG. 2 is an enlarged sectional view of a main part of FIG. 1, and FIG. 3 is an arrow view, FIG. 4 is 4 of FIG.
-4 line view, FIG. 5 is a sectional view taken along line 5-5 of FIG. 4, and FIG. 6 is a view taken along line 6-6 of FIG.

As shown in FIG. 1, the upper part of the outboard motor O is
A two-cylinder vertical engine E, which is covered by a mutually separable upper cover and a lower case that define an engine room R, is mounted. Specifically, the cover is the engine cover 1 that covers the upper half of the engine E,
The case is an oil case 2 in which an engine E is integrally provided with a case portion 2 ₁ for covering a lower half portion and an oil pan portion 2 ₂ . The drive shaft 4 connected in series to the lower end of the crankshaft 3 of the engine E extends downward inside the extension case 5 connected to the lower portion of the oil case 2,
The lower end is connected to a propeller shaft 9 having a propeller 8 at the rear end through a bevel gear mechanism 7 provided inside the gear case 6.

A cooling water pump 10 provided below the drive shaft 4.
The cooling water pumped up through the filter 11 provided at the rear of the gear case 6 is supplied upward through the cooling water pipe 12 to cool the engine E. Further, an exhaust pipe 13 extending downward is fixed to the engine E by a bolt 46, and when the engine E having the exhaust pipe 13 attached thereto is coupled to the oil case 2, the lower end of the exhaust pipe 13 has a lower end of the oil case 2. It is fixed to the lower wall by bolts 18. The lower end opening of the exhaust pipe 13 opens inside the extension case 5. Exhaust gas inside the extension case 5 is discharged into water through an exhaust gas outlet 6 ₁ opening at the rear of the gear case 6.

The stern bracket 15, which supports the outboard motor O so that it can be steered via the swivel case 14, has the lever 1 with the groove portion 15 ₁ whose lower end is open engaged with the stern S.
It is fixed by a push screw 17 operated by 6.

As is apparent from FIGS. 2 to 4, the engine E and the oil case 2 are connected by a plurality of bolts 19 and the extension case 5 and the oil case 2 are connected by a plurality of bolts 20. Are combined. The oil case 2 and the engine cover 1 are locked by a hook 71 and a hook 72 on the front side of the outboard motor O, and a shaft 73 on the rear side of the outboard motor O.
It is locked by a hook lever 74 that rotates around the center, a hook 75 that rotates integrally with the hook lever 74, and a hooked member 76.

The engine E of the outboard motor O is divided into front and rear in a plane including the axis of the crankshaft 3 to define a front crankcase 21 ₁ which defines a part of the crank chamber, and the remaining crankcase. A cylinder block 21 comprising a rear cylinder block 21 ₂ including a skirt portion that closes the portion.
And a cylinder head 22 coupled to the deck surface of the rear cylinder block 21 ₂ . Cylinder block 2
The pair of pistons 23, 23 slidably fitted in 1 and the crankshaft 3 are connected via connecting rods 24, 24, respectively. The cylinder head 22 is formed with a pair of intake ports 25, 25 and exhaust ports 26, 26, respectively.
The two intake ports 27, 27 formed in the two, the bifurcated intake manifold 28, the carburetor 29 having a built-in throttle valve, and the air intake 30 opening inside the engine cover 1 through the intake port opening above the engine cover 1. communicates with the 1 _1, the exhaust port 26 communicates with the upper end of the exhaust pipe 13 through an exhaust port 31 of the bifurcated formed in the cylinder head 22.

As can be seen by referring to FIG. 5 together,
The outer circumference of the exhaust pipe 13 is divided into two exhaust pipe covers 32, 3
The cooling water, which is covered by 3 and is introduced between the inner circumference and the outer circumference of the exhaust pipe 13, flows into the exhaust pipe 13 through the notch 13 ₁ and flows out into the extension case 5 together with the exhaust gas. The exhaust pipe covers 32 and 33 are integrally welded along their flanges 32 ₁ and 33 ₁ ,
Exhaust gas sampling tube 3 having a base end is inserted into the exhaust pipe 13
The outer periphery of 4 is sandwiched between the flanges 32 ₁ and 33 ₁ and welded. Exhaust gas sampling pipe 3 extending rearward from the exhaust pipe 13
Reference numeral 4 is bent to the upper left by approximately 90 °, and its tip portion extends in the vicinity of the joint between the oil case 2 and the engine cover 1.
In order to prevent cooling water from flowing into the exhaust gas sampling pipe 34 and adversely affecting the exhaust gas component measuring instrument, the exhaust gas sampling pipe 3
4 is a notch for introducing cooling water into the exhaust pipe 13.
It is provided above 3 ₁ .

A screw member 35 having a flange 35 ₁ is welded to the tip of the exhaust gas sampling pipe 34, and an opening at the tip of the exhaust gas sampling pipe 34 is attached to the screw member 35.
The plug 36 to be closed is screwed. That is, when the tip of the driver is engaged with the minus groove 36 _{1 formed} in the base end of the plug 36 and rotated, the seal member 37 is inserted between the tip of the plug 36 and the flange 35 ₁ of the screw member 35.
By pinching the (washer), the opening at the tip of the exhaust gas sampling pipe 34 is closed.

In order to inject oil into the cylinder block 21, an oil filler 38 is attached to the opening of the cylinder block wall portion communicating with the inside of the crank chamber. The oil separator 39 provided in the crank chamber and in the front part of the engine E has a small hole 38 formed in the oil filler 38.
₁ and the first blow-by gas passage 40 are connected. The separator 39 separates oil and mist contained in blow-by gas, and the oil separator 39 and the air intake 30 are connected via the second blow-by gas passage 41 in order to return the separated mist to the intake system. To be done.

The inside of the oil separator 39 is connected to the first blow-by gas passage 40 by the partition wall 39 ₁ , and the front chamber 3 is connected.
9 ₂ and a rear chamber 39 ₃ connected to the second blow-by gas passage 41. The front chamber 39 above the oil filler 38 and the _second bottom, the oil return passage 4 for returning the oil from the oil separator 39 in the cylinder block 21
Connected by two. A one-way valve 43 that restricts the reverse flow of mist from the rear chamber 39 ₃ to the front chamber 39 ₂ is attached to the partition wall 39 ₁ of the oil separator 39.

As is apparent from FIGS. 2, 3 and 6,
The air intake 30 includes two bolts 4 that extend in the front-rear direction with their rear end faces abutting against the front end face of the carburetor 29.
It is fixed at 4,44. The intake port 30 ₁ formed at the front end of the air intake 30 is formed so as to be slightly curved downward so that water splash that has entered the inside of the engine cover 1 is not sucked into the intake system. On the upper surface of the air intake 30, the joint portion 30 ₂ extending in the engine E side perpendicular to the axis thereof are formed integrally, the joint portion 30 ₂
The second blow-by gas passage 41 is connected to. Since the joint portion 30 ₂ is arranged at a position shifted upward from the axes of the two bolts 44, 44 for fixing the air intake 30, the attachment / detachment work of the bolts 44, 44 and the attachment / detachment of the second blow-by gas passage 41 are performed. Work is performed without support. Moreover, since the joint portion 30 ₂ extends toward the engine E, that is, in the direction away from the engine cover 1, there is no risk of damaging the second blow-by gas passage 41 when the engine cover 1 is attached or detached.

Reference numeral 45 in FIG. 2 is an endless belt for transmitting the rotation of the crankshaft 3 to the valve operating mechanism.

Next, the operation of the embodiment of the present invention having the above construction will be described.

The outside air sucked into the engine cover ₁ from the intake port 1 ₁ while the engine E is operating is sucked into the carburetor 29 through the air intake 30, and the air-fuel mixture mixed with the fuel there enters the cylinder head 22. It is supplied to the combustion chamber through the formed intake ports 27, 27. Exhaust gas generated in the combustion chamber is guided to the exhaust pipe 13 through an exhaust port 31 formed in the cylinder head 22, and then is discharged into the water from the exhaust gas outlet 6 ₁ of the gear case 6 through the inside of the extension case 5. It At this time, the cooling water pumped up by the cooling water pump 10 provided on the drive shaft 4 passes through the inside of a water jacket (not shown) of the engine E, and a part of the cooling water is exhausted from the exhaust pipe 13 and the exhaust pipe cover 32.
And 33 to cool the exhaust pipe 13. Cooling water and the exhaust pipe 13 is cooled, and flows into the notch 13 ₁ et exhaust pipe 13, and is discharged to the inside of the extension case 5 together with the exhaust gases.

The blow-by gas leaking from the combustion chamber of the engine E into the cylinder block 21 is supplied to the oil separator 39 via the first blow-by gas passage 40.
The mist from which oil has been separated by the oil separator 39 is the second
The carburetor 29 is returned to the inside of the air intake 30 via the blow-by gas passage 41, and the air flowing therethrough is carbureted.
Is supplied to. Then, the oil separated by the oil separator 39 is returned to the inside of the cylinder block 21 via the oil return passage 42 and the oil filler 38.

In order to inspect the exhaust gas components of the engine E, first, the nut 20 with lever is loosened, the engine cover 1 is removed from the oil case 2, and then the exhaust gas sampling pipe 34 is screwed into the tip thereof. Remove the plug 36,
An exhaust gas component measuring device (not shown) may be connected thereto.

At the time of measurement, the engine cover 1 is again attached to the oil case 2, but the piping such as a tube connected to the component measuring instrument is closed by the intake port 1 ₁ of the engine cover ₁ or grommets. It is guided to the outside of the outboard motor O through the opening 2 and the like.

The exhaust gas sampling pipe 34 is connected to the engine E.
The exhaust gas collecting pipe 34 is supported by the exhaust pipe 13 integrated with the exhaust gas collecting pipe 34, and the tip end portion of the exhaust gas collecting pipe 34 opens inside the engine cover 1 and the oil case 2 without penetrating the same. The engine E can be easily assembled. Moreover, the tip of the exhaust gas sampling pipe 34
Not only can the plug 36 that closes the opening of 1 is covered with the engine cover 1 and the oil case 2 to protect it from rust and damage due to the adhesion of seawater, but also the plug 36 can be made inconspicuous and the appearance can be improved.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made.

[0029]

As described above, according to the first feature of the present invention, since the exhaust gas sampling pipe is connected to the exhaust pipe extending downward from the engine, the engine including the exhaust gas sampling pipe can be easily attached and detached. be able to. Moreover, since the exhaust pipe cover divided into two covers the exhaust pipe so as to form a cooling water passage between the exhaust pipe cover and the outer circumference of the exhaust pipe, and the exhaust gas sampling pipe is sandwiched by the mating surface of the exhaust pipe cover, Not only can the exhaust pipe be effectively cooled by the cooling water flowing through the water passage, but also the exhaust gas collection pipe can be firmly fixed using the exhaust pipe cover.

According to the second aspect of the present invention, the tip portion of the exhaust gas sampling pipe extends into the engine room defined by the case means and the engine cover.
At the tip of this exhaust gas sampling pipe, open the tip.
Since the plug for closing the mouth and detachably attached, because it is possible to cover the front end portion of the attachment plug of the exhaust gas sampling pipe in case means or engine cover, exhaust gas sampling pipe Yapu
It is possible to avoid inconveniences such as salt water solidifying or rusting due to sea water being applied to the rug , or being caught on another article during transportation.

[Brief description of drawings]

FIG. 1 is an overall side view of an outboard motor according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of the main part of FIG.

FIG. 3 is a view taken along the line 3-3 of FIG.

4 is a view taken along the line 4-4 of FIG.

5 is a sectional view taken along line 5-5 of FIG.

6 is a view taken along the line 6-6 of FIG.

[Explanation of symbols]

1 engine cover 2 Oil case (case means) 5 Extension case (case means) 6 Gear case (case means) 8 propellers 13 Exhaust pipe 31 exhaust port 32 Exhaust pipe cover 33 Exhaust pipe cover 34 Exhaust gas sampling pipe E engine

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI F02B 67/00 F02B 67/00 NR 77/00 N 77/00 B63H 21/26 E (58) Fields investigated (Int.Cl . ⁷ , DB name) B63H 20/24 F01N 7/12 G01N 1/22

Claims (2)

(57) [Claims] 1. An engine (E) and this engine (E)
And a case means (2, 5, 6) for rotatably supporting the propeller (8).
An engine cover (1) which is detachably provided on the case means (2, 5, 6) and covers the engine (E) from above; and the case means (1) from the exhaust port (31) of the engine (E). 2, 5, 6) an exhaust pipe (13) extending downward from the engine (E) so as to guide the exhaust gas to the lower part of the internal space, and an exhaust gas sampling pipe (34) connected to the exhaust pipe (13). ) And an exhaust gas sampling device for an outboard motor, the exhaust pipe (13) covering the exhaust pipe (13) so as to form a cooling water passage between the exhaust pipe and the outer periphery thereof. A split exhaust pipe cover (32, 33) is provided, and the exhaust gas sampling pipe (34) is sandwiched between the mating surfaces of the exhaust pipe covers (32, 33). Exhaust gas sampling device. 2. A tip portion of the exhaust gas sampling pipe (34)
To the inside of the engine room (R) defined by the case means (2, 5, 6) and the engine cover (1), and at the tip of the exhaust gas sampling pipe (34).
Attach and remove the plug (36) that closes the opening at the tip of the
The exhaust gas sampling apparatus for an outboard motor according to claim 1, wherein the exhaust gas sampling apparatus is mounted so as to be capable of being mounted .