JPH10218089A - Vapor separator of outboard motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make fuel system pipes simple and compact by arranging a vapor separator on the halfway of a fuel hose which connects a fuel tank with a delivery pipe and arranging a fuel pump and a pressure regulator in a case of the vapor separator. SOLUTION: A fuel supply device of an outboard motor 1 consists of a connector 39, a plurality of fuel filters 460, 41, a mechanical pump 42,1 a vapor separator 44, a pressure regulator, a delivery pipe 46, an injector 25, etc., and each part is connected by fuel hoses. In this case, a space is formed between each suction pipes 37,... of a cylinder block 16 and a suction manifold 38, and a separator case having the functions of the vapor separator 44 which separates vapor contained in gasoline and releases bubbles of vapor into the atmosphere is arranged in this space. A fuel pump and the pressure regulator are arranged in this case.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vapor separator for an outboard motor.

[0002]

2. Description of the Related Art A fuel supply system for an engine having a fuel injection system has a pressure regulator downstream of a fuel pump for regulating fuel pressure. Examples of the arrangement of the pressure regulator include, for example, Japanese Patent Application Laid-Open No. 8-218.
As disclosed in Japanese Patent Publication No. 984, a fuel pump and a pressure regulator are arranged in the middle of a fuel hose connecting a fuel pump and a delivery pipe and in a fuel tank.

[0003] A fuel supply device for an engine is provided with a vapor separator that separates liquid fuel, for example, gasoline vapor contained in gasoline, releases only bubbles of this vapor to the atmosphere, and sends fuel without bubbles to a fuel pump. Some have been provided.

Incidentally, in an outboard motor often used for small boats, the fuel tank is generally provided on the boat side separately from the outboard motor. Also, not all outboard motors are equipped with a fuel injection system.For example, a carburetor type does not use a fuel pump or a pressure regulator. It is not practical to place the fuel pump and pressure regulator inside.

Therefore, as shown in, for example, JP-A-7-317617, a fuel pump and a pressure regulator are provided on the outboard motor side, and a fuel reservoir is provided in the middle of a fuel hose connecting the fuel tank and the fuel pump. There is a type in which a tank is disposed and excess fuel from a pressure regulator provided downstream of a delivery pipe is returned to an intermediate tank via a return pipe.

Further, as shown in, for example, Japanese Utility Model Application Laid-Open No. 7-55327, a vapor separator is disposed in the middle of a fuel hose connecting a fuel tank and a delivery pipe, and a fuel pump is provided in a case of the vapor separator. There is a type in which surplus fuel from a pressure regulator provided downstream of a delivery pipe is returned to a vapor separator via a return pipe.

[0007]

However, if the pressure regulator is provided downstream of the delivery pipe, a pipe for returning excess fuel to the intermediate tank and the vapor separator is required. It gets complicated.

The present invention has been made in view of the above circumstances, and has as its object to provide a vapor separator for an outboard motor in which fuel system piping is simplified.

Another object of the present invention is to provide a vapor separator for an outboard motor which is made compact.

It is still another object of the present invention to provide a vapor separator for an outboard motor having an increased fuel overflow limit.

Another object of the present invention is to provide a vapor separator for an outboard motor which suppresses generation of fuel vapor.

[0012]

SUMMARY OF THE INVENTION A vapor separator for an outboard motor according to the present invention has the following features.
As described in claim 1, a vapor separator is disposed in the middle of a fuel hose connecting a fuel tank and a delivery pipe, and a fuel pump and a pressure regulator are disposed in a case of the vapor separator.

According to another aspect of the present invention, the pressure regulator is integrally provided immediately above the fuel pump.

Further, in order to solve the above-mentioned problems,
As described in claim 3, the case of the vapor separator is configured to be vertically separable, and the pressure regulator and the float are arranged in the upper case,
A swing shaft of a hinge for swingably supporting the float is provided on the forward direction of the boat and above the fuel pump, and the fuel pump is disposed in a lower case of the divided vapor separator.

Further, in order to solve the above-mentioned problem, a water jacket is formed in a case of the vapor separator as described in claim 4.

[0016]

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

FIG. 1 is a left side view of an outboard motor to which the present invention is applied. The outboard motor 1 includes an engine holder 2 and is mounted on a transom 4a of a hull 4 via a bracket 3 attached to the engine holder 2.

An engine 5 is installed on the upper part of the engine holder 2, and its periphery is covered with an engine cover 6. The engine cover 6 can be vertically divided into an upper cover 6a and a lower cover 6b, and the lower cover 6b can be further divided into left and right. The periphery of the engine holder 2 and the lower part of the engine 5 are covered by a lower cover 6b, and the upper part of the engine 5 is covered by an upper cover 6a.

A crankshaft 7 is provided vertically inside the engine 5 so as to be directed substantially vertically. A drive shaft housing 9 is provided below the engine holder 2 with an oil pan 8 interposed therebetween. A drive shaft 10 connected to a lower end of the crankshaft 7 extends downward in the oil pan 8 and the drive shaft housing 9, and a bevel gear 12 and a propeller in a gear case 11 provided at a lower portion of the drive shaft housing 9. It is configured to drive a propeller 14 via a shaft 13.

FIG. 2 is an enlarged left side view of the engine 5 in FIG. 1, and FIG. 3 is a sectional view taken along the line III-III in FIG. As shown in FIGS.
Is a water-cooled cycle four-cylinder engine, for example, and is configured by combining a cylinder head 15, a cylinder block 16, a crankcase 17, and the like.

A cylinder 18 is formed in a cylinder block 16 of the engine 5. Also, the cylinder head 15
Is formed with a combustion chamber 19 that matches the cylinder 18, and a spark plug 20 is connected from the outside thereof. A piston 21 is slidably inserted in the cylinder 18 in the horizontal direction, and the piston 21 and the crankshaft 7 are connected by a connecting rod 22. Then, the reciprocating stroke of the piston 21 is converted into the rotational movement of the crankshaft 7.

In the cylinder head 15, an intake port 23 and an exhaust port 24 connected to the combustion chamber 19 are formed.
An injector 25 for injecting fuel into the intake port 23 is attached to the cylinder head 15 from outside. Further, both ports 23, 2 are provided in the cylinder head 15.
An intake valve 26 and an exhaust valve 27 for opening and closing the valve 4 are disposed, and a valve operating device 30 such as a camshaft 28 and a rocker arm 29 for opening and closing these valves 26 and 27.
Is also arranged. Then, the cylinder head 15 is covered by the cylinder head cover 31.

An electrical component 32, an intake device 33, and a fuel supply device 34 are arranged around the engine 5. Intake device 33
Is mainly composed of a throttle body 35, an intake manifold 38 having a surge tank 36 and a plurality of intake pipes 37 extending from the surge tank 36 for each cylinder. You. Also,
The electrical component 32 is arranged on the opposite side of the intake device 33 and the throttle body 35 is arranged, for example, in front of the crankcase 17 of the engine 5.
The surge tank 36 is juxtaposed on the side of the fifth tank 5. The intake pipes 37 are vertically arranged on the side of the cylinder block 16 and communicate the intake ports 23 of the cylinder head 15 with the inside of the surge tank 36.

FIG. 4 is a block diagram of the fuel supply device 34. As shown in FIG. 4, the fuel supply device 34 has a fuel system component such as a filter and a pump.
9 and a plurality of fuel filters 40 and 41 and a fuel pump 4
2, 43, vapor separator 44, pressure regulator 45, delivery pipe 46, injector 25
The components are connected by fuel hoses 47 and 48.

The outboard motor 1 shown in this embodiment has a fuel tank 4
9 is provided on the hull 4 side, and a fuel supply hose (not shown) extending from the fuel tank 49 is connected to a connector 39 provided on the lower cover 6b. The surge tank 3
A low-pressure filter 40 is fixed to the lower surface of 6, and the low-pressure filter 40 and the connector 39 are connected by a low-pressure fuel hose 47a.

A mechanical pump (low-pressure fuel pump) 42 driven by the camshaft 28 is disposed on the cylinder head cover 31.
And the low pressure filter 40 are connected by a low pressure fuel hose 47b.

A space is formed between the cylinder block 16 and each of the intake pipes 37 of the intake manifold 38, and a separator case 50 having the function of a vapor separator 44 is disposed in this space. The separator case 50 is fixed inside each of the intake pipes 37. The vapor separator 44 separates liquid fuel, for example, gasoline vapor contained in gasoline, and releases only bubbles of this vapor to the atmosphere. The fuel is guided from the mechanical pump 42 through a low-pressure fuel hose 47c.

A high-pressure fuel pump 43 and a pressure regulator 45 are also provided in the separator case 50.
The fuel from which the vapor bubbles have been separated is pumped at a predetermined pressure through a high-pressure fuel hose 48a to a high-pressure filter 41 fixed at a lower portion of the intake pipes 37.

The high-pressure fuel sent to the high-pressure filter 41 is sent to a delivery pipe 46 attached to the intake pipes 37 via a high-pressure fuel hose 48b. The injectors 25 are attached to the delivery pipes 46 for each cylinder, and the injectors 25 inject high-pressure fuel into the intake ports 23.

FIG. 5 is a left side view of the vapor separator 44, and FIG. 6 is a front view of the vapor separator 44. 7 is a cross-sectional view taken along the line VII-VII of FIG. 6, and FIG. 8 is a cross-sectional view taken along the line VIII-VIII of FIG. As shown in FIGS. 5 to 8, the separator case 50 of the vapor separator 44 is configured to be vertically splittable into an upper case 51 and a lower case 52.

A fuel inlet 53 is provided on the upper surface of the upper case 51 on the side of the hull 4 in the forward direction (hereinafter, simply referred to as the front side), and the mechanical pump 4 is connected via a low-pressure fuel hose 47c.
2 (see FIG. 2). A fuel outlet 54 is provided on the rear side of the upper surface of the upper case 51, and is connected to the high-pressure filter 41 via a high-pressure fuel hose 48a (FIG. 2).
reference). A breather port 55 for releasing gasoline vapor bubbles to the atmosphere is formed adjacent to the fuel discharge port 54, and a breather tube 56 is connected to the breather port 55 (see FIG. 2).

A needle valve 57 is provided at an outlet 53a of the fuel inlet 53 disposed on the inner surface of the upper case 51, and a float 58 is provided near the outlet 53a. The float 58 is swingably supported via a hinge 60 on a swing shaft 59 provided on the inner surface of the upper case 51 on the front side of the outlet 53a. For example, the needle valve 57 is attached to the hinge 60.

On the other hand, the fuel outlet 5 on the inner surface of the upper case 51
A pressure regulator 45 is mounted on the upstream side of 4, and a high-pressure fuel pump 43 is mounted on the upstream side. The pressure regulator 45 is connected to the fuel pump 4.
3 and is provided integrally therewith.

On the other hand, the lower case 52 has a fuel reservoir inside, and the high pressure fuel pump 43 attached to the inner surface of the upper case 51 is immersed in the fuel 61. Also,
A drain 63 that can be opened and closed by a screw 62 is provided at the lowermost part on the front side of the lower case 52. Further, a water jacket 64 is provided on an outer wall portion of the lower case 52,
As shown by an arrow 65 in FIG. 5, cooling water (for example, seawater) is circulated.

Next, the operation of the present embodiment will be described.

The fuel in the fuel tank 49 is sucked up by the mechanical pump 42, filtered by the low-pressure filter 40, and then guided from the fuel inlet 53 of the vapor separator 44 into the separator case 50. Lower case 52
When the oil level of the fuel 61 inside reaches a predetermined amount, the float 58 rises, and the needle valve 57 closes the outlet 53a of the fuel inlet 53 to restrict the inflow of fuel, thereby preventing overflow. Further, when the oil level decreases with the consumption of the fuel 61, the float 58 lowers to release the outlet 53a of the fuel inlet 53, and the fuel is supplied.

The fuel 61 accumulated in the lower case 52 is separated into vapor, and only bubbles of this vapor are released to the atmosphere from the breather port 55, and fuel without bubbles is discharged from the fuel discharge port 54 by the high-pressure fuel pump 43. High-pressure filter 41,
Then, it is pressure-fed to the delivery pipe 46.

When the fuel consumption decreases due to the low rotation speed of the engine 5 and the pressure of the fuel in the delivery pipe 46 becomes higher than a specified value, the pressure between the high-pressure fuel pump 43 and the fuel discharge port 54 increases. The arranged pressure regulator 45 is opened and excess fuel is returned into the separator case 50 of the vapor separator 44 to lower the fuel pressure.

Since the high-pressure fuel pump 43 and the pressure regulator 45 are arranged in the case of the vapor separator 44, the delivery pipe 46 which is conventionally required is provided.
The piping for returning excess fuel from the fuel system is not required, and the piping of the entire fuel system is simplified. In addition, troubles such as cracks in the surplus fuel return pipe are eliminated. Further, the high-pressure fuel pump 43 and the pressure regulator 45 are protected from salt damage (corrosion), and the durability of the outboard motor 1 is improved.

Further, by integrally providing the pressure regulator 45 directly above the fuel pump 43, the vapor separator 44 can be made compact.

Further, the separator case 50 is configured to be vertically splittable, and a float 58 is provided in the upper case 51.
And the float 58 is swingably supported via a hinge 60 on a swing shaft 59 provided on the front side of the inner surface of the upper case 51, so that the fuel overflow limit is increased, and the outboard motor 1 Fuel overflow is prevented when tilting up, tilting down, or steering left and right.

Further, by arranging the low-pressure filter 40 on the upstream side of the vapor separator 44 and the high-pressure filter 41 on the downstream side of the vapor separator 44, the work of replacing each filter is facilitated and the maintainability is improved.

Further, since the drain 63 is provided at the lowermost part on the front side of the separator case 50, the fuel in the vapor separator 44 can be reliably drained with the outboard motor 1 tilted up, so that the maintainability is improved. Good.

Then, a water jacket 64 is formed in the separator case 50 of the vapor separator 44, and cooling water is circulated inside the water jacket 64 to cool the fuel in the separator case 50, thereby suppressing generation of fuel vapor. In addition, the water jacket 64 may be compact for direct cooling using low-temperature seawater as cooling water,
Easy to assemble.

[0045]

As described above, according to the vapor separator of the outboard motor according to the present invention, the vapor separator is disposed in the middle of the fuel hose connecting the fuel tank and the delivery pipe, and the inside of the case of the vapor separator is provided. The fuel pump and pressure regulator
Excess fuel return piping is not required, and the fuel system piping can be simplified.

Further, since the pressure regulator is integrally provided immediately above the fuel pump, the vapor separator can be made compact.

Further, the case of the vapor separator is configured to be vertically splittable, the pressure regulator and the float are arranged in the upper case, and the swing shaft of the hinge for swingably supporting the float is mounted on the ship. Since the fuel pump is provided in the forward direction and above the fuel pump and the fuel pump is arranged in the lower case of the divided vapor separator, the fuel overflow limit is increased.

Furthermore, since the water jacket is formed in the case of the vapor separator, generation of fuel vapor in the case is suppressed.

[Brief description of the drawings]

FIG. 1 is a left side view of an outboard motor showing one embodiment of a vapor separator of the outboard motor according to the present invention.

FIG. 2 is an enlarged left side view of an engine part of FIG. 1;

FIG. 3 is a sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a block diagram of a fuel supply device.

FIG. 5 is a left side view of the vapor separator.

FIG. 6 is a front view of a vapor separator.

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 6;

FIG. 8 is a sectional view taken along the line VIII-VIII in FIG. 7;

[Explanation of symbols]

 Reference Signs List 1 outboard motor 5 engine 25 injector 33 intake device 34 fuel supply device 40 low-pressure filter 41 high-pressure filter 42 mechanical pump (low-pressure fuel pump) 43 high-pressure fuel pump 44 vapor separator 45 pressure regulator 46 delivery pipe 47a-c low-pressure fuel hose 48a- b High-pressure fuel hose 49 Fuel tank 50 Separator case 51 Upper case 52 Lower case 53 Fuel inlet 54 Fuel discharge port 55 Breather port 57 Needle valve 58 Float 59 Swing shaft 60 Hinge 63 Drain 64 Water jacket

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02M 37/20 F02M 37/20 K 69/00 69/00 340T 340 320J

Claims (4)

[Claims] 1. A fuel tank 49 and a delivery pipe 46.
A vapor separator 44 is arranged in the middle of fuel hoses 47 and 48 connecting the fuel pump 43 and the pressure regulator 4 in a case 50 of the vapor separator 44.
5. A vapor separator for an outboard motor, comprising: 2. The outboard motor vapor separator according to claim 1, wherein said pressure regulator is integrally provided immediately above said fuel pump. 3. The case 5 of the vapor separator 44.
The pressure regulator 45 and the float 58 are arranged in an upper case 51 of the vessel 4 and a swing shaft 59 of a hinge 60 that supports the float 58 so that the float 58 can swing is moved in the forward direction of the boat 4. Side and above the fuel pump 43, and the fuel pump 43 is provided in the lower case 52 of the divided vapor separator 44.
The vapor separator for an outboard motor according to claim 1, wherein 4. The case 5 of the vapor separator 44.
4. The vapor separator for an outboard motor according to claim 1, wherein a water jacket is formed on the outboard motor.