JPH052828B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a fuel supply device for an outboard motor.

[Prior Art] Conventionally, a fuel supply system for an outboard motor consists of a fuel tank separate from the engine unit, a carburetor connected to an intake passage provided in the engine, a fuel supply nozzle of the carburetor, and a fuel tank. A fuel supply passage formed between the fuel supply passage and an engine-side fuel joint and a tank-side fuel joint that are disposed in the middle of the fuel supply passage and are detachable from each other are used.

On the other hand, as described in Japanese Patent Application Laid-open No. 132061/1983, in order to remove moisture from fuel, "a water separation device having a water separation chamber placed in the middle of a fuel supply passage, and a water separation device" has been proposed. A fuel supply device has been proposed that includes a drain pipe that discharges water from the lower part of a chamber, and an openable on-off valve disposed in the drain pipe.

Therefore, it is conceivable to provide a water separation device as described above in the fuel supply passage of the outboard motor.

[Problems to be Solved by the Invention] However, the fuel supply device described in the above-mentioned Japanese Patent Application Laid-Open No. 60-132061 does not allow water in the water separation chamber to flow due to the head of fuel between the on-off valve and the fuel tank. Therefore, unless the fuel oil level in the tank is higher than the opening/closing valve position, it is impossible to discharge water even if the opening/closing valve is opened. Further, when the fuel oil level in the tank is higher than the on-off valve position, if the on-off valve is forgotten to close, the fuel will not flow.

The present invention provides a fuel supply device in which a fuel tank is removably attached to an engine unit, in which the water in the water separation chamber can be reliably discharged, and even when the on-off valve is forgotten to close, the fuel does not flow out from the water separation chamber. The purpose is to make it possible to prevent this from happening.

[Means for Solving the Problems] The present invention provides a fuel tank separate from the engine unit, a carburetor connected to an intake passage provided in the engine, and a fuel tank between the fuel supply nozzle of the carburetor and the fuel tank. In an outboard motor fuel supply system, the fuel supply system for an outboard motor includes a fuel supply passage formed in the fuel supply passage, and an engine-side fuel joint and a tank-side fuel joint that are disposed in the middle of the fuel supply passage and are mutually detachable. a water separation device having a water separation chamber located downstream of the engine-side fuel joint; a fuel pressure pump located upstream of the water separation device in the fuel supply passage;
A check valve formed between a water separation device in a fuel supply passage and a fuel supply nozzle, a drain pipe that discharges water from the lower part of the water separation chamber, and an openable on-off valve disposed in the drain pipe. is located between the water separator in the fuel supply passage and the engine-side fuel joint, and can be opened when the fuel pressure pump is in use. The valve is provided with a pressure valve that does not open due to the head of fuel in between, and the space between the check valve, the pressure valve, and the on-off valve is kept airtight.

[Operation] According to the present invention, if the pump is operated with the on-off valve open, the water in the water separation chamber can be discharged by the pressure generated by the pump. The operation of the pump may be stopped after confirming that the discharged water is switched to fuel. When the tank is separated from the engine unit, even if the on-off valve is open, the atmospheric pressure acting on the open end of the drain pipe will prevent the fuel in the water separation chamber from flowing out. As described above, in the fuel supply device in which the fuel tank is removably attached to the engine unit, water in the water separation chamber can be reliably discharged, and
Even if you forget to close the on-off valve, it is possible to prevent fuel from flowing out of the water separation chamber.

[Embodiment] FIG. 1 is a side view schematically showing an outboard motor 10 to which a first embodiment of the present invention is applied, and FIG.
The piping system diagram of the embodiment, FIG. 3 is a plan view showing the on-off valve of FIG. 2.

The outboard motor 10 is mounted on a boat 11 with a bracket 1
2, and an engine unit 14 is mounted on the upper part of the propulsion unit 13. 10A is a cowling. The engine unit 14 includes an engine 15, a carburetor 16, an intake box 1
It has 7. The carburetor 16 is connected to an intake passage provided in the engine 15, and is connected to the float chamber 1.
8, a needle valve 20 that is opened and closed by a float 19 in a float chamber 18, and a fuel supply nozzle 21. On the other hand, a fuel tank 22 is arranged inside the ship 11.

The fuel supply nozzle 21 of the carburetor 16 and the fuel tank 22 are connected by a fuel supply passage 23. The fuel supply passage 23 is the engine side passage 2
3A and a tank side passage 23B, both of which are connected to an engine side fuel joint 24A and a tank side fuel joint 24.
B and can be attached to and detached from each other.

The engine-side fuel joint 24A and the tank-side fuel joint 24B are connected to the engine-side fuel joint 24A by connecting the integral protruding pipe 25 to the connection hole 2 of the tank-side fuel joint 24B.
A rod 30 is inserted into the inside of the O-ring 27 attached to the engine side fuel joint 24A, and is integral with the valve body 29 which is supported on the back side by the spring 28 within the engine side fuel joint 24A.
Due to the collision between the valve body 32 and the valve body 32 which is supported on the back side by a spring 31 within the tank-side fuel joint 24B, the valve body 2
9 from the O-ring 33 and the valve body 32 from the O-ring 27, it is possible to communicate the engine-side passage 23A and the tank-side passage 23B. In addition, for the above-mentioned communication, the valve body 29 is provided with a slit 34, and the valve body 3 is provided with a slit 34.
The connecting hole 26 around the connecting hole 26 is provided with a slit 35. The connection state between the engine-side fuel joint 24A and the tank-side fuel joint 24B is determined by the engagement of an engagement pin 36 integrated with the engine-side fuel joint 24A and a lever 37 integrated with the tank-side fuel joint 24B. considered to be retainable.

By removing the outboard motor 10 from the vessel 11, etc.
Engine side fuel joint 24A and tank side fuel joint 2
4B, the valve body 29 in the engine-side fuel joint 24A closes tightly against the O-ring 33 by the spring 28, and the valve body 32 in the tank-side fuel joint 24B closes by the spring 28. 31, it is closed in close contact with the O-ring 27.

The valve body 29 constitutes a pressure valve in the present invention, as described later.

Engine side fuel joint 24A of fuel supply passage 23
A water separation device 38 is arranged further downstream. The water separation device 38 includes a water separation chamber 39 that can separate water in the fuel, and a drain pipe 40 that discharges water from the lower part of the water separation chamber 39. An openable on-off valve 41 is arranged in the drain pipe 40. The on-off valve 41 can be opened and closed by a manual knob 42. In addition, the drain pipe line 4
The open end of the cowling 10A of the outboard motor 10 is located in an external area of the cowling 10A of the outboard motor 10.

Upstream of the water separation device 38 in the fuel supply passage 23, that is, in the middle part of the tank side passage 23B,
A manual fuel pump 43 is arranged.

Further, a diaphragm fuel pump 44 is disposed downstream of the water separation device 38 in the fuel supply passage 23 . The fuel pump 44 is connected to the crank chamber 45
A diaphragm chamber 46 that communicates with
It is divided by 8. Each of the suction port 49 connected to the tank 22 side of the pump chamber 47 and the discharge port 50 connected to the carburetor 16 side is provided with a check that allows fuel to flow only from the tank 22 side to the carburetor 16 side. Valves 51 and 52 are provided.

That is, the manual fuel pump 43 can fill the fuel supply passage 23 with the fuel in the tank 22 by manual operation. Further, the fuel pump 44 is operated by pressure pulsations inside the crank chamber 45 due to operation of the engine 15, and can pump fuel inside the tank 22 to the carburetor 16.

The manual fuel pump 43 constitutes a fuel pressure pump in the present invention, and the check valves 51, 52
constitutes the check valve in the present invention. Further, the valve body 29 in the engine side fuel joint 24A constitutes a pressure valve in the present invention, and the engine side passage 24A constitutes a pressure valve in the present invention.
3A and the tank side passage 23B are connected,
It opens as described above, and does not open due to the head of fuel between the engine side fuel joint 24A and the open end of the drain pipe 40 when the engine side passage 23A and the tank side passage 23B are separated. It is set as follows. In addition, the engine side passage 23A
In this case, the spaces between the check valves 51 and 52, the valve body 29, and the on-off valve 41 are kept airtight.
Note that 53 is a fuel filter.

Next, the operation of the first embodiment will be explained.

In the first embodiment, the manual fuel pump 4
When the engine 15 is started after the fuel supply passage 23 is filled with fuel by the operation in step 3, the fuel pump 44 is activated and the fuel in the tank 22 can be supplied to the carburetor 16. At this time, water in the fuel is separated by the water separator 38 and remains in the water separation chamber 39.

However, when the engine 15 is stopped, the on-off valve 41
If the manual fuel pump 43 is operated in the open state, the pressure generated by the pump 43 will cause the water separation chamber 3 to
It becomes possible to drain the water inside 9. The operation of the pump 43 may be stopped after confirming that the discharged water is switched to fuel. Further, when the engine side passage 23A and the tank side passage 23B are separated by removing the outboard motor 10 from the vessel 11, etc., even if the on-off valve 41 is in the open state, the engine side fuel joint 24A Since the valve body 29 maintains airtightness and the check valves 51 and 52 also maintain airtightness, the fuel in the water separation chamber 39 will not flow out due to the atmospheric pressure acting on the open end of the drain pipe 40.

That is, according to the first embodiment, in the fuel supply device in which the fuel tank 22 is removably attached to the engine unit 14, the water inside the water separation chamber 39 can be reliably discharged, and the on-off valve 41 can be closed. Even if you forget, it is possible to prevent fuel from flowing out from the water separation chamber 39.

FIG. 4 is a piping system diagram showing a second embodiment of the present invention, and the same members as in the first embodiment are designated by the same reference numerals. This second embodiment is similar to the first embodiment.
The difference from the embodiment is that the diaphragm fuel pump 44 is replaced by a water separator 3 in the fuel supply passage 23.
8, and this pump 44 is used as the fuel pressure pump in the present invention, and the carburetor 1
The point is that the needle valve 20 of No. 6 is used as a check valve in the present invention. Note that the manual fuel pump 43 may or may not be provided in this second embodiment. Further, a check valve 60 may be provided between the water separator 38 and the vaporizer 16 in the fuel supply passage 23.

Next, the operation of the second embodiment will be explained.

In the second embodiment, when the engine 15 is operating, the diaphragm fuel pump 44 is activated to supply fuel in the fuel tank 22 to the carburetor 16. At this time, water in the fuel is separated by the water separator 38 and remains in the water separation chamber 39.

Therefore, while the engine 15 is operating, the on-off valve 4
1, the water in the water separation chamber 39 can be discharged by the pressure generated by the pump 44.
By confirming that the discharged water is switched to fuel and operating the stop switch of the engine 15, it is possible to stop the discharge of the water. In addition, when the fuel tank 22 is removed from the engine unit 14, even if the on-off valve 41 is in the open state, the valve body 29 in the engine side fuel joint 24A
maintains airtightness, and the needle valve 20 of the vaporizer 16 also maintains airtightness, so the atmospheric pressure acting on the open end of the drain pipe 40 will not cause the fuel in the water separation chamber 39 to flow out.

[Effects of the Invention] As described above, the present invention provides a fuel tank separate from the engine unit, a carburetor connected to an intake passage provided in the engine, and a fuel tank between the fuel supply nozzle of the carburetor and the fuel tank. In an outboard motor fuel supply system, the fuel supply system for an outboard motor includes a fuel supply passage formed in the fuel supply passage, and an engine-side fuel joint and a tank-side fuel joint that are disposed in the middle of the fuel supply passage and are mutually detachable. A water separation device having a water separation chamber located downstream of the engine side fuel joint, a fuel pressure pump located upstream of the water separation device in the fuel supply passage, a water separation device in the fuel supply passage and the fuel supply A check valve formed between the nozzles, a drain pipe that discharges water from the lower part of the water separation chamber, an openable on-off valve disposed in the drain pipe, a water separation device in the fuel supply passage, and an engine. It is located between the side fuel joints and can be opened when the fuel pressure pump is in use, and can also open depending on the head of fuel between the engine side fuel joint and the open end of the drain pipe when both of the above fuel joints are in the disengaged state. Equipped with a constant pressure valve,
The space between the check valve, pressure valve and on-off valve is kept airtight.

Therefore, according to the present invention, if the pump is operated with the on-off valve open, the water in the water separation chamber can be discharged by the pressure generated by the pump. The operation of the pump may be stopped after confirming that the discharged water is switched to fuel.
When the tank is separated from the engine unit, even if the on-off valve is open, the atmospheric pressure acting on the open end of the drain pipe will prevent the fuel in the water separation chamber from flowing out. As a result of the above, in a fuel supply system in which the fuel tank is detachable from the engine unit, the water in the water separation chamber can be reliably discharged, and even if you forget to close the on-off valve, the fuel can flow out from the water separation chamber. This makes it possible to prevent this.

[Brief explanation of the drawing]

Fig. 1 is a side view schematically showing an outboard motor to which one embodiment of the present invention is applied, Fig. 2 is a piping system diagram of the first embodiment, and Fig. 3 shows the on-off valve of Fig. 2. The plan view shown in FIG. 4 is a piping system diagram showing a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 10... Outboard motor, 11... Ship, 14... Engine unit, 15... Engine, 16... Carburizer, 20...
Needle valve (check valve), 21...fuel supply nozzle,
22...Fuel tank, 23...Fuel supply passage, 24A
...Engine side fuel joint, 29...Valve body (pressure valve),
38...Water separation device, 39...Water separation chamber, 40...Drain pipe, 41...Opening/closing valve, 43...Manual fuel pump,
44...Diaphragm fuel pump, 51, 52...
Check valve, 60...Check valve.

Claims (1)

[Claims] 1 An engine unit, a separate unit, a fuel tank, a carburetor connected to an intake passage provided in the engine, a fuel supply passage formed between the fuel supply nozzle of the carburetor and the fuel tank, and an intermediate part of the fuel supply passage In a fuel supply system for an outboard motor, which is provided with an engine-side fuel joint and a tank-side fuel joint that are arranged in a water separation device having a chamber; a fuel pressure pump disposed upstream of the water separation device in the fuel supply passage; a check valve formed between the water separation device in the fuel supply passage and the fuel supply nozzle; A drain pipe that discharges water from the bottom of the separation chamber, an openable on-off valve located in the drain pipe, and a fuel pressure pump located between the water separation device in the fuel supply passage and the fuel joint on the engine side. a pressure valve that can be opened at times and that does not open due to the head of fuel between the engine side fuel joint and the open end of the drain pipe when both the fuel joints are in the disengaged state; A fuel supply system for an outboard motor, characterized in that a space between the pressure valve and the on-off valve is maintained airtight.