JP2552843B2 - Fuel supply device for outboard motors - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fuel supply device for an outboard motor mounted on a ship as a ship propulsion device.

[Conventional technology]

The outboard motor, which is fixed to the hull and has a spark ignition type internal combustion engine having a carburetor with a float valve disposed at the fuel inlet of the float chamber, has fuel in a fuel tank arranged in the hull.
When the fuel pump is operated, the fuel is supplied through the first fuel passage, the manual pump, and the second fuel passage between the manual pump and the carburetor.

[Problems to be Solved by the Invention]

By the way, the driver operates the manual pump at the time of starting the engine to store the fuel in the float chamber.
At the time of this start-up and subsequent operation, the float valve that constantly controls the fuel oil level in the float chamber controls the buoyancy of the float so that the fuel does not exceed the control oil level and overflow from the needle by the operation of the manual pump. It is designed to close the fuel inlet of the float chamber.

The outboard motor is held in a tilted up state in order to prevent sticking of the crucible or corrosion when the mooring is not used. In this tilt-up state, the float valve
Since the fuel inlet of the float chamber cannot be closed, when the manual pump was operated by mistake, the fuel sometimes overflowed from the nozzle.

On the other hand, even if the manual pump is accidentally stepped on even in the tilt-down state, the pump pressure of the manual pump becomes extremely high, the fuel overcomes the buoyancy of the float and enters the float chamber pressure, and the fuel in the float chamber is set. Since it was above the level, the fuel supplied from the carburetor to the engine was sometimes excessive.

Therefore, the present invention provides a fuel supply device for an outboard motor,
Regardless of whether the outboard motor is tilted up or tilted down, it is necessary to prevent the fuel from being supplied to the engine in excess of a specified amount or leaking from the fuel supply device due to an incorrect operation of the manual pump. It is an issue.

[Means for solving the problem]

In order to solve the above problems, the present invention mounts a spark ignition type internal combustion engine having a carburetor fixed to a hull and having a float valve at a fuel inlet of a float chamber, and covers the spark ignition type internal combustion engine. A fuel tank used for an outboard motor having an engine cowling and arranged on the hull, a fuel pump for supplying fuel from the fuel tank to the carburetor during operation, and a fuel carburetor that is manually operated to start the internal combustion engine. And a first fuel passage between the fuel tank and the manual pump, and a second fuel passage between the manual pump and the carburetor. In an outboard motor fuel supply device having a detachable engine-side fuel joint and a tank-side fuel joint, before fixing the engine-side fuel joint to the outer surface of the engine cowling and connecting it A tank-side fuel joint is disposed a manually-off opening and closing valves between the manual pump.

[Action]

When starting the internal combustion engine, the fuel in the fuel tank arranged in the hull is supplied to the carburetor by manual operation of the manual pump, and during operation, the fuel is supplied from the fuel tank to the carburetor by the fuel pump. A first fuel passage between the fuel tank and the manual pump, and a second fuel passage between the manual pump and the carburetor, and an engine-side fuel joint and a tank which are detachable from each other in the middle of the second fuel passage. A side fuel joint is provided. An engine-side fuel joint is fixed to the outer surface of the engine cowling, and an on-off valve that can be manually opened and closed is arranged between a tank-side fuel joint connected to the engine cowling and a manual pump.
By closing the on-off valve, even if there is an operation such as accidentally stepping on the manual pump, the fuel is not supplied to the carburetor and does not leak from the fuel joint on the tank side.

〔Example〕

FIG. 1 is a side view schematically showing a state in which the first embodiment of the present invention is applied to an outboard motor 10.

The outboard motor 10 is rotatable around a tilt shaft 13 and a bracket 12 fixed to the hull 11, and thus the bracket
The thruster main body 14 is supported so as to be tiltable with respect to 12. An engine unit 15 is mounted on the top of the propulsion unit body 14. 15A is an engine cowling for preventing the engine unit 15 from being directly exposed to seawater.

The engine unit 15 is an engine (spark ignition internal combustion engine) 16, which is electrically ignited by a spark plug (not shown),
It has a vaporizer 17 and an intake silencer 18. A float valve is arranged at the fuel inlet of the float chamber of the carburetor 17, and the fuel supplied by the fuel supply device 20 is stored in the float chamber.

The fuel supply device 20 includes a fuel tank 2 mounted on the hull 11.
1, a fuel pump 22 for supplying fuel from the fuel tank 21 to the carburetor 17 during operation, a manual pump 23 for supplying fuel to the carburetor 17 by manual operation when the engine 16 is started, and a fuel tank 21. The fuel pipes A and 24 that serve as the first fuel passage between the manual pump 23, the manual pump 23, and the carburetor 17
And a second fuel passage 25 disposed between the second fuel passage 25 and the second fuel passage 25, and an on-off valve 26 that can be opened and closed manually.

The second fuel passage 25 includes fuel pipes B, 27 and fuel pipes C, 2
8, fuel pipe D, 31, fuel pipe E, 33, and fuel pipe
It consists of F and 34. An opening / closing valve 26 having a manual opening / closing lever 26a is arranged between the fuel pipes B and 27 and the fuel pipes C and 28,
A tank side fuel joint 29 and an engine side fuel joint 30 are arranged between the fuel pipes C and 28 and the fuel pipes D and 31, and a fuel filter is arranged between the fuel pipes D and 31 and the fuel pipes E and 33. 32 is provided, and the fuel pump 22 is provided between the fuel pipes E and 33 and the fuel pipes F and 34.

The tank-side fuel joint 29 and the engine-side fuel joint 30 fixedly arranged on the engine cowling 15A are detachably connected to each other. The components of the fuel supply device 20 from the fuel pipe D, 31 to the fuel pipe F, 34 are the engine cowling 15A.
To be housed. On the other hand, the components of the fuel supply device 20 from the fuel tank 21 to the fuel joint 29 on the tank side are the fuel tank 21.
It can be carried together with.

In this embodiment, when the tank-side fuel joint 29 and the engine-side fuel joint 30 are connected, if the manual pump 23 is accidentally stepped on, the fuel will be sent to the carburetor 17. , Turn the manual open / close lever 26a to open / close the open / close valve 26
The fuel supply to the carburetor 17 is cut off by closing the.

FIG. 2 is a cross-sectional view of a main part of a fuel supply system for an outboard motor of a second embodiment of the present invention, and the configuration common to the first embodiment is partially omitted. FIG. 3 is an external view of the on-off valve portion as viewed along the arrow III in FIG.

The manual pump 23 mainly includes a flexible and shape-resilient rubber main body 40, an inflow side check ball valve 41, and an outflow side check ball valve 42. In addition, it has a band 43 for preventing leakage. Each check ball valve 41, 42 has a check ball 44 and a stopper 45 built therein.

The tank-side fuel joint 29 is mainly composed of the joint body 46, the joint body 46.
Fuel passage 47 penetrating through and the connection hole forming the fuel passage 47
48 has a spring 49, a ball-shaped valve body 50 back-supported by the spring 49, an inner diameter smaller than the valve body 50, and a connection hole 48.
O-ring 51 placed at the mouth of the lever, a retaining lever that is rotatable on the joint body 46 and is back-supported by a spring 52.
It consists of 53. Further, the tank side fuel joint 29 is connected to the fuel passage.
An opening / closing valve body 54 having a manual opening / closing lever 26a for manually opening / closing 47 and a sleeve 55 are provided. The connection hole 48 around the valve body 50 is provided with a plurality of slits 56, and the fuel can pass through the slits 56.

The engine side joint 30 includes a joint main body 57, a fuel passage 58 penetrating the joint main body 57, and a protruding pipe 59 fixed to the joint main body 57.
And the engaging pin 60, the spring 61, the valve body 63 which is supported by the spring 61 on the back surface and includes the slit 62, the rod 64 which is integral with the valve body 63, and the O-ring 65 which is arranged on the protruding tube 59. Become. The joint body 57 is arranged outside the engine cowling 15A and is fixed with bolts 66.
A part of 57 extends into the opening of the engine cowling 15A.

In the figure, the projecting pipe 59 of the engine side joint 30 is inserted into the inside of the O-ring 51 of the tank side fuel joint 29, and the rod 64 and the valve body 50 are abutted to each other, so that the spring 61 and the spring 49 respectively.
Is compressed, and the valve element 63 and the valve element 50 are respectively O-rings.
It is separated from 65 and O-ring 51. As a result, the fuel passage 58 on the engine side and the fuel passage 47 on the tank side are communicated with each other. Further, since the engaging pin 60 is inserted into the fitting hole of the joint body 46 and the retaining pin 53 is engaged with the engaging pin 60, the tank side fuel joint 29 and the engine side fuel joint.
The 30 are firmly connected to each other and held.

When carrying the fuel tank 21, if the fuel joint 29 on the tank side is pulled out from the fuel joint 30 on the engine side, the valve body 50 and the valve body 63 are respectively provided with a spring 49 and a spring 61, and an O-ring 51 and an O-ring 65, respectively. Close and close, no fuel leaks.

The fuel pump 22 is attached to the crankcase 67, and the drive chamber 69 of the main bodies A and 68 communicates with the crank chamber 70. Body B, 71
Check valves 72 and 73 are provided in the. 74 is a diaphragm and 75 is a spring. The fuel pump 22 pressure-feeds fuel due to pressure fluctuations in the crank chamber 70 after the engine is started.

The carburetor 17 is maintained in an intake passage provided in the engine, and includes a float chamber 76, a float 77 in the float chamber 76, a float valve 78, a link 79 for opening and closing the float valve 78 by transmitting movement of the float 77, and an intake passage. A fuel supply nozzle 80 for ejecting fuel by the negative pressure is provided. The closing pressure of the float valve 78 is given by the buoyancy of the float 77. In this closing valve, the float 77 tilts in the float chamber 76,
Alternatively, there is a limit to the size, so it cannot be too large.

The check ball valves 41, 42, the check valves 72, 73, and the float valve 78 all have the function of allowing the flow of fuel in the direction from the fuel tank 21 to the float chamber 76 and preventing the reverse flow. Clips 81 are provided on both sides of each fuel pipe so that fuel will not leak due to pressure increase by the manual pump 23 or the fuel pump 22.

The fuel supply device of the present embodiment configured as described above,
When the fuel oil level of the float chamber 76 is tilted in the tilt-up state, the float 77 no longer presses the link 79, and the float valve 78 cannot be closed.
When the manual pump 23 is operated in the tilt-up state,
The fuel in the manual pump 23 may pass through the opened float valve 78, enter the float chamber 76, and overflow from the nozzle 80. However, by turning the manual opening / closing lever 26a and closing the fuel passage 47, overflow can be prevented.

If the closing valve cannot be taken large, the same effect can be obtained regardless of the tilt-up or tilt-down state. Further, in this embodiment, the on-off valve 26 is formed integrally with the tank-side joint 29, and is fixed to the outboard motor via the engine-side joint 30 that is connected and held. Is easy to operate.

FIG. 4 is a schematic diagram showing a third embodiment. The third embodiment differs from the first embodiment in that the opening / closing valve 26 is connected to the engine side joint.
It is integrally formed on the substrate 30, and the other points are similar to those of the first embodiment.

〔The invention's effect〕

In the present invention, the second fuel passage between the manual pump and the carburetor is provided, and the engine-side fuel joint and the tank-side fuel joint which are detachable from each other are provided in the middle of the second fuel passage. An open / close valve that can be manually opened / closed is provided between and. Therefore, if the on-off valve is closed, no fuel will flow past the on-off valve.If the outboard motor is tilted up or tilted down and the manual pump is accidentally operated or stepped on, In addition, a predetermined amount or more of fuel is not supplied to the carburetor, the engine, etc., and does not leak from the fuel supply device (for example, the seal portion of the engine side fuel joint) located ahead of the on-off valve. If the fuel joint on the tank side is removed from the fuel joint on the engine side, even if the fuel flows toward the fuel joint on the tank side due to an unexpected sudden operation of the pump, if the on-off valve is closed, it will reach the fuel joint on the tank side. The fuel does not leak from the sealing portion of the fuel joint on the tank side.

In the present invention, the engine-side fuel joint is fixed to the outer surface of the engine cowling, and the on-off valve that can be manually opened and closed is arranged between the tank-side fuel joint connected to the engine cowling and the manual pump. Since the on-off valve is arranged outside the engine cowling in this way, the on-off valve can be operated without the need to take off the engine cowling. Further, when starting the engine, it is necessary to open the opening / closing valve in order to flow the fuel to the carburetor side. However, if the opening / closing valve is inside the engine cowling, it is easy to forget the opening operation. However, in the present invention, since the open / close valve is outside the engine cowling, the open / closed state can be visually recognized, and the opening operation of the open / close valve is not forgotten.

[Brief description of drawings]

FIG. 1 shows an outboard motor 10 to which the first embodiment of the present invention is applied.
It is a side view which shows typically. FIG. 2 is a sectional view of the essential parts of a fuel supply system for an outboard motor according to a second embodiment of the present invention. Third
The drawing is an external view of the on-off valve portion as viewed along the arrow III in FIG. FIG. 4 is a schematic diagram showing the third embodiment. 10 …… Outboard motor, 25 …… Second fuel passage 16 …… Engine, 26 …… Opening / closing valve 17 …… Vaporizer, 29 …… Tank side fuel joint 20 …… Fuel supply device, 30 …… Engine side fuel Joint 21 …… Fuel tank, 76 …… Float chamber 22 …… Fuel pump, 77 …… Float 23 …… Manual pump, 78 …… Float valve 24 …… First fuel passage, 79 …… Link

Continuation of the front page (56) Reference JP-A-60-93168 (JP, A) JP-A-62-129560 (JP, A) Actually opened 52-85035 (JP, U) Actually opened 49-145049 (JP , U) Actual development Sho 56-66058 (JP, U)

Claims (1)

(57) [Claims] 1. An outboard motor having a spark ignition type internal combustion engine fixed to a hull and having a carburetor having a float valve arranged at a fuel inlet of a float chamber, and having an engine cowling for covering the spark ignition type internal combustion engine. Used for the fuel tank, which is placed in the hull, a fuel pump for supplying fuel from the fuel tank to the carburetor during operation, and a manual pump for supplying fuel to the carburetor by manual operation when starting the internal combustion engine. And one fuel passage between the fuel tank and the manual pump, and a second fuel passage between the manual pump and the carburetor, and an engine-side fuel joint that is detachable from each other in the middle of the second fuel passage. In an outboard motor fuel supply device having a tank-side fuel joint, the engine-side fuel joint is fixed to an outer surface of the engine cowling, and the tank-side fuel joint and the manual coupling connected to the engine-side fuel joint are fixed. The fuel supply system for an outboard motor, characterized in that arranged a manually-off opening and closing valve between the pump.