JPH04295172A - Fuel feeding device for outboard motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply system for an outboard motor that connects an inboard fuel tank and an outboard motor with a hose and injects fuel into an intake manifold.

0002

2. Description of the Related Art Large outboard motors have a fuel tank carried inside the boat, and the fuel tank and outboard motor are connected with a hose, and fuel is supplied to the outboard motor using a low pressure pump. For this reason, it is difficult to provide a return hose to the fuel tank. For this reason, the outboard motor is equipped with a vapor separator that also serves as a sub-tank to maintain a constant oil level using a float valve.
Furthermore, when injecting fuel into the engine's intake manifold with an injector, the fuel is forced from the vapor separator to the injector using a high-pressure pump. For example, see Japanese Patent Application Laid-Open No. 62-253955.

0003

[Problems to be Solved by the Invention] A high-pressure pump installed inside an outboard motor needs to be vibration-proofed so that it is not directly exposed to engine vibration. Also, install the high pressure pump below the vapor separator to prevent aeration. For this reason, there are significant restrictions on the mounting position of the high-pressure pump. If it is installed too low, it will be exposed to water splashes and problems with corrosion resistance will occur.

[0004] In view of the above, the present invention provides a high-pressure pump that is installed in a vapor separator that also serves as a sub-tank that is installed inside an outboard motor, and that the suction port of the high-pressure pump can be placed below the oil level of the vapor separator. The purpose of this invention is to solve the problem of the mounting height of a high-pressure pump and to obtain a fuel supply device for an outboard motor that has excellent rust and corrosion resistance.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the outboard motor fuel supply system of the present invention connects a fuel tank brought into the boat to the outboard motor with a hose, and connects the fuel tank brought into the boat to the outboard motor using a low pressure pump. Fuel is sent to the vapor separator installed at the bottom, a high pressure pump is installed inside the vapor separator, the high pressure pump pumps the fuel to the injector via the delivery pipe, and excess fuel is sent from the delivery pipe to the vapor separator via the pressure regulator. It's because I returned it.

[0006]

[Operation] The high-pressure pump can be installed inside the vapor separator and the suction port can be placed below the oil level of the vapor separator. Since the high-pressure pump is located within the vapor separator and isolated, there is no need to worry about water splashing, and rust and corrosion can be prevented. Additionally, piping connecting the vapor separator and the high pressure pump is no longer necessary.

[0007]

Embodiments Hereinafter, embodiments of the present invention will be explained with reference to FIGS. 1 to 5. FIG. 4 shows an outboard motor that is a four-cylinder, four-stroke engine that injects fuel into an intake manifold 1 through an injector 2, with a crankshaft 3 placed vertically. The fuel tank 4 is portable inside the boat, and is connected to the outboard motor through a hose 5 and a joint 6. And squeeze valve 7 and low pressure filter 8
The fuel is sent to the vapor separator 10 by a low pressure pump 9 through the vapor separator 10 . The vapor separator 10 operates an on-off valve 12 using a float 11 floating on the oil level to maintain a constant oil level. The vapor separator 10 is fastened to the lower part of the crankcase 14 via an elastic bush 13. A vapor port 1 is provided at the upper end of the vapor separator 10.
5 is provided, and is connected by a vapor hose 16 near a throttle valve 18 attached to the inlet of a surge tank 17 of the intake manifold 1, so that it is inhaled together with intake air.

A cylindrical high-pressure pump 19 is inserted into one side of the vapor separator 10 . High pressure pump 19
The lower end is inserted into the cushion piece 20, and the upper end is connected to the discharge port 22 through the cushion tube 21. High pressure pump 1
9 inhales fuel from the suction port 23 at the lower end, and the discharge port 22
The fuel is pumped to the A lead wire 24 of a power source that drives the high-pressure pump 19 is sealed with a grommet, inserted into the vapor separator 10, and connected to the high-pressure pump 19. The discharge port 22 is connected to a high pressure filter 25
The pipe is connected to the delivery pipe 26 via. Each injector 2 of the intake manifold 1 is connected to the delivery pipe 26 . Further, the delivery pipe 26 is connected to the pressure regulator 28, and the return pipe 27 is connected to the return port 2 of the vapor separator 10.
Connect to 9. The return port 29 is set at a position that does not hinder the movement of the float 11.

The interior of the vapor separator 10 is maintained at a constant oil level by opening and closing an on-off valve 12 using a float 11, and the suction port 23 of the high-pressure pump 19 is located at the lower end of the vapor separator 10 and is always kept below the oil level. To position. The fuel pumped by the high-pressure pump 19 is then delivered to the delivery pipe 2.
6, the fuel is distributed to each injector 2 and injected. Excess fuel in the delivery pipe 26 is returned to the vapor separator 10 via the pressure regulator 28. The vapor generated in the vapor separator 10 is sent to the vicinity of the throttle valve 18 by a vapor hose 16, and is inhaled together with intake air.

The vapor separator 10 is attached to the lower part of the crankcase 14 via an elastic bush 13.
The transmission of vibrations is attenuated, and the high-pressure pump 19 in the vapor separator 10 is attached with a cushion piece 20 and a cushion tube 21 to reduce the transmission of vibrations. The high pressure pump 19 has an inlet 23
is always under the oil level of the vapor separator 10 and is isolated from the outside by the vapor separator 10.

[0011]

[Effects of the Invention] As explained above, since the present invention is constructed as described above, the suction port of the high-pressure pump is installed below the oil level of the vapor separator, and the vertical relationship between the vapor separator and the high-pressure pump is maintained. can. Furthermore, since the high-pressure pump is located within the vapor separator and isolated from the outside, there is no need to worry about water splashing or the like, and the pump can have excellent rust and corrosion resistance. Additionally, piping between the vapor separator and the high-pressure hose is no longer necessary, making piping easier. The high-pressure pump has double vibration isolation at the vapor separator mounting section and the high-pressure pump mounting section, making it easy to install the high-pressure pump.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view of a vapor separator showing an embodiment of the present invention.

FIG. 2 is a side view of a vapor separator according to an embodiment of the present invention, taken longitudinally through a float portion.

FIG. 3 is a piping system diagram showing an embodiment of the present invention.

FIG. 4 is a cross-sectional plan view of an engine equipped with a vapor separator according to an embodiment of the present invention.

FIG. 5 is a longitudinal sectional side view of an engine in an embodiment of the present invention.

[Explanation of symbols]

2 Injector 4 Fuel tank 5 Hose 9 Low pressure pump 10 Vapor separator 14 Crank case 19 High pressure pump 26 Delivery pipe 28 Pressure regulator

Claims (1)

[Claims] [Claim 1] Connect the fuel tank brought onboard to the outboard motor with a hose, send fuel to a vapor separator installed at the bottom of the crankcase using a low-pressure pump, install a high-pressure pump inside the vapor separator, and deliver fuel using the high-pressure pump. A fuel supply system for an outboard motor, which is characterized by pressure-feeding fuel to an injector through a pipe, and returning surplus fuel from a delivery pipe to a vapor separator through a pressure regulator.