JP2003172222A - Fuel supply equipment in fuel tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel supply equipment in a fuel tank capable of restraining generation of bubble in a chamber at a main tank side even if a sub-tank side is empty. <P>SOLUTION: As a receiving plate 29 against which a fuel N injected downward from a suction pump 15 for the sub-tank hits is formed at an inner wall surface of a chamber 8, the fuel N is guided to a lower side along the inner wall surface of the chamber 8 and thus generation of bubble in the chamber 8 is restrained. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply device in a fuel tank.

[0002]

2. Description of the Related Art A fuel pump for discharging fuel toward an external engine side is provided inside a fuel tank of an automobile, as known from Japanese Patent Laid-Open No. 2001-270336. If the fuel in the fuel tank suddenly accelerates or decelerates when the remaining amount is low, the liquid level in the fuel tank may be greatly inclined, causing a fuel shortage near the suction port of the fuel pump. A bottomed cylindrical chamber surrounding the fuel pump is attached from the upper plate that closes the opening of the fuel tank toward the inside of the fuel tank, and a fuel pool is formed around the fuel pump. In the chamber, in addition to the fuel pump, a pressure regulator for returning a part of the fuel discharged from the fuel pump to the chamber as return fuel in order to adjust the pressure of the fuel sent to the engine.

Some fuel tanks are a saddle type fuel tank having a main tank and a sub tank inside due to restrictions on the layout of installation on the vehicle body. In the case of such a saddle type fuel tank, a chamber containing the above-mentioned fuel pump and pressure regulator is provided on the main tank side, and the fuel on the sub-tank side is introduced by a sub-tank suction pump provided in the chamber. It is led to the chamber side via a pipe.

The sub-tank suction pump has a tubular shape capable of injecting the return fuel from the pressure regulator downward, and a fuel introduction pipe from the sub-tank is joined in the middle to generate a negative pressure when the return fuel is ejected at a high speed. By utilizing this, the fuel in the sub-tank can be supplied to the chamber side together with the return fuel.

[0005]

However, in such a conventional technique, the suction pump for the sub-tank sucks the fuel on the sub-tank side together with the return fuel and supplies the fuel into the chamber. When the sub tank is emptied, the return fuel ejected from the sub tank suction pump is mixed with the air from the sub tank to form a gas-liquid mixed flow. Then, when the return fuel of the gas-liquid mixture is blown out from the sub-tank suction pump to the bottom surface of the chamber, bubbles are generated in the fuel in the chamber,
When the fuel pump sucked the fuel in which the bubbles were generated, an unpleasant suction noise was generated in the fuel pump.

The present invention has been made by paying attention to such a conventional technique, and it is possible to suppress the generation of bubbles in the chamber on the main tank side even if the sub tank side becomes empty. And a fuel supply device for the same.

[0007]

According to a first aspect of the present invention, an upper plate is attached to an opening formed on the main tank side in an upper surface portion of a fuel tank provided with a main tank and a sub tank, and the upper plate is attached. A bottomed cylindrical chamber that forms a fuel pool in the main tank is attached to the lower part of the, and a fuel pump that delivers fuel to the engine and a fuel pump that delivers fuel to the engine in a state of being fixed to the upper plate side in the chamber. Fuel provided with a pressure regulator for returning a portion of the fuel as return fuel into the chamber, and a suction pump for the sub tank in which the return fuel can be injected downward and a fuel introduction pipe from the sub tank is joined in the middle A fuel supply device in a tank, which is located at a position higher than a bottom surface portion of the inner wall surface of the chamber, and faces downward from the sub-tank suction pump. To form a receiving plate has injected fuel hits.

According to the first aspect of the present invention, since the receiving plate against which the fuel injected downward from the sub-tank suction pump hits is formed at a position higher than the bottom portion of the inner wall surface of the chamber, the fuel is receiving plate. Is guided downward along the inner wall surface of the chamber, and the generation of bubbles in the chamber is suppressed. Therefore, the generation of unpleasant noise when sucking the fuel in the chamber with the fuel pump is reduced.

According to the second aspect of the invention, the receiving plate is inclined downward in the inner peripheral direction along the inner wall surface of the chamber.

According to the second aspect of the present invention, since the receiving plate is inclined downward in the inner peripheral direction along the inner wall surface of the chamber, the fuel jetted downward from the sub-tank suction pump is further reduced. The state is along the inner wall surface of the chamber, and the generation of bubbles in the chamber is further suppressed.

According to the third aspect of the present invention, a spiral rib is formed on the inner wall surface of the chamber, the spiral rib being continuous from the lower end of the receiving plate and being gradually inclined downward along the inner wall surface of the chamber. ing.

According to the third aspect of the present invention, since the spiral ribs are continuously formed on the receiving plate on the inner wall surface of the chamber, the fuel jetted downward from the sub-tank suction pump extends along the ribs. Since it is smoothly guided to the lower part of the chamber, the generation of bubbles in the chamber is further suppressed.

According to a fourth aspect of the present invention, the inclination angles of the receiving plate and the rib are substantially the same.

According to the fourth aspect of the invention, since the inclination angles of the receiving plate and the ribs are substantially the same, the flow of fuel from the receiving plate to the ribs is smooth and turbulence hardly occurs.

According to a fifth aspect of the invention, in the chamber,
It has a downward cylindrical shape into which the return fuel is introduced and has a nozzle at the lower end that injects the return fuel from the suction chamber communicating with the outside of the chamber toward the inside of the chamber. A suction pump for the main tank that supplies the

According to the fifth aspect of the invention, the fuel outside the chamber can be supplied into the chamber by the suction pump for the main tank using the pressure of the return fuel from the pressure regulator.

According to a sixth aspect of the present invention, in the chamber,
A suction chamber that communicates with the outside of the chamber is provided in the flow path through which the return fuel that flows spirally along the ribs passes, and an auxiliary main tank that supplies the fuel outside the chamber with the return fuel into the chamber. A suction pump was provided.

According to the sixth aspect of the present invention, the flow of the fuel jetted from the sub-tank suction pump is guided to the auxiliary main-tank suction pump via the spiral rib so that the fuel can be discharged outside the chamber. Since it can be used to supply the fuel into the chamber, the pressure of the return fuel can be effectively used.

According to a seventh aspect of the present invention, the chamber is vertically movable with respect to the upper plate, and the main tank suction pump is extensible and retractable following the chamber.

According to the invention as set forth in claim 7, since the chamber can be vertically stroked and the main tank suction pump can be expanded and contracted, the bottom of the chamber fluctuates up and down due to changes in the internal pressure of the fuel tank. It is possible to easily follow the lower surface portion.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view showing the internal structure of the fuel tank 1. The fuel tank 1 has a saddle shape including a main tank 2 and a sub tank 3. The fuel N is contained in both the main tank 2 and the sub tank 3. An opening 5 is formed in the upper surface portion 4 on the main tank 2 side, and an upper plate 6 is attached to the opening 5 from above.

A cylindrical support 7 is integrally formed on the lower portion of the upper plate 6. A chamber 8 having a bottomed cylindrical shape is attached to the lower portion of the cylindrical support 7 so as to be vertically stroked in an inscribed state, and a projection 9 formed on the upper portion of the chamber 8 is provided with a slit formed on the lower portion of the cylindrical support 7. It is in a state of being engaged with 10.

In the chamber 8, the fuel pump 11 for supplying fuel, the filter element 12 for purifying the fuel N, and the fuel N to be sent to the outside in a state of being fixed to the cylindrical support 7 side.
, A pressure regulator 13 for adjusting the pressure of the tank to a constant level, a main tank suction pump 14 for supplying the fuel N in the main tank 2 into the chamber 8, and a sub tank suction pump 15 for supplying the fuel N in the sub tank 3 into the chamber 8. Is provided.

A filter 16 is provided below the fuel pump 11.
A suction port 17 covered with is provided so that the fuel N in the chamber 8 can be sucked and delivered from the suction port 17. As shown in FIG. 3, the fuel N delivered from the fuel pump 11 is filtered by passing through a filter element 12, and a nozzle 19 formed in an upper portion of the upper plate 6 from a central passage 18 causes an engine (not shown). Is supplied to the injection valve.

A return passage 20 branches off from a part of the central passage 18, and a pressure regulator 13 is installed in the middle of the return passage 20. A ball valve that opens and closes with a spring set to a predetermined pressure is provided in the pressure regulator 13, and the ball valve opens when the pressure on the side of the central passage 18 rises above a predetermined value so that the fuel N Return section 2
The pressure of the fuel N sent to the engine is made constant by escaping to the 0 side.

The main tank side suction pump 14 is provided in each of the return passages 20 after passing through the pressure regulator 13.
And the sub-tank suction pump 15 is provided in parallel. The main tank side suction pump 14 has a return passage 2
The upper cylinder 14a communicating with the bottom part 21 of the chamber 8
It is inserted into the lower cylinder 14b in which the lower end is in communication with the suction chamber 22 formed in the above, so that the whole can be expanded and contracted in the vertical direction.

The upper end of the lower cylinder 14b and the return passage 2
A spring 23 is provided between the lower cylinder 14 and
B is urged downward. At the lower end of the lower tube 14b,
A nozzle 24 for injecting the return fuel n from the suction chamber 22 into the chamber 8 is provided. Therefore, when the return fuel n is injected from the nozzle 24, the suction chamber 22 has a negative pressure, the fuel N outside the chamber 8 is sucked into the suction chamber 22, and is supplied into the chamber 8 together with the return fuel n. It Therefore, the fuel N is stored in the chamber 8 and the fuel pump 11
Can be inhaled by.

Further, since the main tank side suction pump 14 is biased by the spring 23 in the extending direction, the position of the lower surface portion 25 of the main tank 2 in the chamber 8 is adjusted by its own weight and the biasing force of the spring 23. Even if the pressure fluctuates up and down due to changes in the internal pressure, etc., the state in which it is in contact with the lower surface portion 25 is always maintained, and the fuel N can be sucked from the deepest position of the main tank 2.

The sub-tank suction pump 15 also has a tubular shape capable of injecting the return fuel n from the return passage 20 downward, and has a conical tubular nozzle portion 26 at the base end portion. A suction passage 28, to which the fuel introduction pipe 27 from the sub-tank 3 is connected, is joined to an intermediate portion below the nozzle portion 26. Therefore, the return fuel n
Is injected downward from the sub-tank suction pump 15, the return fuel n becomes high speed below the nozzle portion 26 to generate a negative pressure. Due to the negative pressure, the fuel N in the sub tank 3 is sucked through the fuel introduction pipe 27 and is supplied into the chamber 8 together with the return fuel n. The suction passage 28, to which the fuel introducing pipe 27 is connected, extends to the outside of the cylindrical support 7 from a not-shown notch formed in the cylindrical support 7 at the lower part of the upper plate 6.

A receiving plate 29 attached to the inner wall surface of the chamber 8 is located just below the sub-tank suction pump 15. The receiving plate 29 is attached to a position higher than the bottom surface portion 21 on the inner wall surface of the chamber 8 and is inclined downward by a predetermined angle θ1 in the inner peripheral direction along the inner wall surface of the chamber 8.

Further, a receiving plate 29 is provided on the inner wall surface of the chamber 8.
A spiral rib 30 is formed continuously from the lower end of the same along the inner wall surface of the chamber 8 and is gradually inclined downward. The inclination angle θ2 of the rib 30 is the inclination angle θ1 of the receiving plate 29.
(Θ1 = θ2), the inner wall surface of the chamber 8 is about 2 /
It has reached the bottom portion 21 after three rotations.

An auxiliary main tank suction pump 31 is provided on the bottom portion 21 of the chamber 8 near the lower end of the rib 30. The auxiliary main tank suction pump 31 has a substantially tunnel shape and has a chamber 8 inside.
Is formed with a suction chamber (not shown) that communicates with the outside.

Therefore, when the return fuel n is injected downward from the sub-tank suction pump 15, the return fuel n is returned.
First hits the receiving plate 29. Since the backing plate 29 is formed on the inner wall surface of the chamber 8 and is inclined downward in the inner circumferential direction along the inner wall surface of the chamber 8, the return fuel n hitting the backing plate 29 will not contact the inner wall surface of the chamber 8. You will be guided to the lower side along. Moreover, in this embodiment, since the spiral rib 30 is continuously formed on the receiving plate 29, the return fuel n
Are guided to the bottom surface portion 21 of the chamber 8 along the spiral rib 30. Furthermore, since the inclination angles θ1 and θ2 of the receiving plate 29 and the rib 30 are the same, the flow of the fuel N from the receiving plate 29 to the rib 30 is smooth and no turbulence occurs.

Therefore, in the unlikely event that the sub-tank 3 side becomes empty, the sub-tank 3 in the sub-tank suction pump 15 is emptied.
Even if only air is mixed with the return fuel n from the fuel introduction pipe 27 of the above, the return fuel n of the gas-liquid mixture is guided by the inner wall surface of the fuel tank 1 and the ribs 30 as described above, Since it is guided to the bottom surface portion 21 of 8, the generation of bubbles in the chamber 8 is suppressed. Therefore, even if the fuel N in the chamber 8 is sucked by the fuel pump 11 and supplied to the engine side, no unpleasant noise is generated. The effect of suppressing the generation of bubbles in the chamber 8 is as follows.
Even if there is no 0, it can be obtained only by the backing plate 29, but the rib 30
It is possible to more reliably suppress the generation of bubbles by forming the.

When the return fuel n is guided to the bottom surface portion 21 of the chamber 8 along the rib 30 in this way, the return fuel n
Of the return fuel n
Flow through the auxiliary main tank suction pump 31 formed in the vicinity of the lower end of the rib 30, a negative pressure is generated in the suction chamber inside the auxiliary main tank suction pump 31, and the outside of the chamber 8 The fuel N can be fed into the chamber 8 together with the return fuel n. As described above, the flow of the return fuel n from the sub-tank suction pump 15, which has been used only for sucking the fuel N from the sub-tank 3 side up to now, is guided to the auxiliary main tank suction pump 31 and the main tank 2 Since it can also be used to suck the fuel N from the fuel tank 1, the pressure of the return fuel n can be effectively used.

[Brief description of drawings]

FIG. 1 is a sectional view showing a fuel tank according to an embodiment of the present invention.

FIG. 2 is a plan view showing a fuel supply device.

FIG. 3 is a cross-sectional view of the fuel supply device taken along the line SA-SA shown in FIG.

FIG. 4 is a perspective view showing a receiving plate and ribs formed in the chamber.

[Explanation of symbols] 1 fuel tank 2 main tank 3 sub tank 4 Upper surface 5 openings 6 Upper plate 8 chambers 11 Fuel pump 13 Pressure regulator 14 Main tank suction pump 15 Sub tank suction pump 21 Bottom part 22 Suction chamber 25 Lower surface 27 Fuel introduction pipe 29 Receiving plate 30 ribs 31 Auxiliary main tank suction pump θ1 Inclination angle of receiving plate θ2 Rib inclination angle N fuel n Return fuel

Claims (7)

[Claims] 1. An upper plate is attached to an opening formed on a main tank side in an upper surface of a fuel tank provided with a main tank and a sub tank, and a fuel pool is formed in the main tank below the upper plate. A bottom cylinder-shaped chamber is attached, and a fuel pump that delivers fuel to the engine in a state of being fixed to the upper plate side in the chamber, and a part of the fuel delivered to the engine is returned to the chamber as return fuel. A fuel supply device in a fuel tank, comprising: a pressure regulator; and a sub-tank suction pump in which a fuel introduction pipe from a sub-tank is joined in the middle of a tubular shape capable of injecting return fuel downward. A receiving plate against which the fuel injected downward from the sub-tank suction pump hits was formed at a position higher than the bottom surface of the inner wall surface. The fuel supply system in the fuel tank, wherein the door. 2. The fuel supply device for a fuel tank according to claim 1, wherein the receiving plate is inclined downward in an inner peripheral direction along an inner wall surface of the chamber. Fuel supply device in the tank. 3. The fuel supply device for a fuel tank according to claim 2, wherein the inner wall surface of the chamber is continuous from the lower end of the receiving plate and gradually lowers along the inner wall surface of the chamber. A fuel supply device in a fuel tank, characterized in that a spiral rib inclined inward is formed. 4. The fuel supply apparatus for a fuel tank according to claim 3, wherein the inclination angles of the receiving plate and the ribs are substantially the same. . 5. The fuel supply device for a fuel tank according to any one of claims 1 to 3, wherein the fuel supply device has a downward cylindrical shape into which return fuel is introduced into the chamber and has a chamber at the lower end. A suction pump for a main tank is provided which has a nozzle for injecting return fuel from the suction chamber communicating with the outside toward the inside of the chamber, and which supplies the fuel outside the chamber into the chamber together with the return fuel. Fuel supply device in the fuel tank. 6. The fuel supply device for a fuel tank according to claim 5, wherein a flow path through which the return fuel spirally flowing along the ribs passes through the chamber is provided outside the chamber. A fuel supply device in a fuel tank, characterized in that a suction pump for a main tank is provided which is provided with a communicating suction chamber and supplies the fuel outside the chamber into the chamber together with the return fuel. 7. The fuel supply device for a fuel tank according to claim 5, wherein the chamber is vertically strokeable with respect to an upper plate, and a suction pump for a main tank follows the chamber. The fuel supply device in a fuel tank is characterized by being expandable and contractible.