Fuel supply device

Abstract

To provide a fuel supply device capable of supplying fuel to an engine in such a stable state that no vapor and impurities are mixed therein while preventing harmful effects from being caused when surplus fuel from a regulator flows down.SOLUTION: A regulator 6 is held by a holding member 7 fixed to the reverse of a lid body 2 in such a manner that surplus fuel is discharged from a discharge port 63 to a position located on a liquid surface 51 of a fuel storage tank 11 while avoiding the operation region of a float 5. Thus, the shake of the liquid surface 51 on the float 5 side due to the surplus fuel discharged from the discharge port 63 of the regulator 6 is suppressed to prevent the bubbling of fuel. The fuel can be supplied to the engine in such a stable state that no vapor and impurities are mixed therein.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a regulator holding member in a fuel supply system having a reservoir that is disposed midway in a fuel supply pipe connecting a fuel tank and an engine and is used to supply fuel stored in the fuel tank to the engine. [Background technology]

[0002] Conventionally, when liquid fuel stored in a fuel tank is supplied to an engine, it is necessary to supply fuel without interruption even in the event of sudden acceleration or deceleration. For this reason, a fuel supply device equipped with a reservoir has been used; for example, one disclosed in JP 2008-297941 A is known. This fuel supply device includes a fuel pump that supplies fuel stored in a fuel tank formed in a housing main body that forms a fuel storage tank that also serves as a reservoir, to the engine from a fuel discharge pipe, a float with an adjustment function for maintaining the liquid level of the fuel stored in the fuel storage tank at a predetermined position, and a regulator that adjusts the pressure of fuel supplied to the engine from the fuel pump located in the fuel storage tank formed in the housing main body, with a pressure adjustment port formed at the upper end of the regulator main body incorporating an adjustment pressure member connected to the fuel discharge pipe and a return port formed below the regulator main body communicating with the fuel storage tank.

[0003] The regulator used in the fuel supply system disclosed in the publication is configured, like regulators used in many other fuel supply systems, to return excess fuel to the fuel storage tank while regulating the pressure of the pumped fuel to a predetermined level.

[0004] However, with the above-mentioned fuel supply device, there is a concern that when excess fuel flows down from the regulator into the storage tank, vapor may be generated in the fuel, or the liquid level of the stored fuel may be disturbed, causing the float to swing and the liquid level of the stored fuel to become unstable, which may prevent a stable supply of fuel from the fuel pump to the engine.

[0005] In addition, while the fuel storage tank has the effect of removing the accumulation of moisture and impurities contained in the fuel, there is also the problem that when excess fuel flows down from the regulator, the moisture and impurities accumulated at the bottom are remixed and supplied to the engine.

[0006] Therefore, in a fuel supply device arranged midway through a fuel supply pipe to supply liquid fuel stored in a fuel tank to an engine, the applicant of the present application has invented a fuel supply device that prevents the adverse effects caused by excess fuel flowing down from a regulator into the fuel stored in a fuel storage tank, and enables a stable supply of fuel free of impurities to the engine. This fuel supply device is disclosed, for example, in JP 2016-205169 A, JP 2018-105129 A, and the like.

[0007] In the fuel supply device disclosed in these publications, as shown in FIG. 5, a regulator 5a is inserted and held above a float 4a disposed inside a housing main body 3a which contains a fuel pump 1a and a fuel storage tank 2a, and a gutter-shaped surplus fuel drainage passage 6a is formed which reaches from the discharge portion of the regulator 5a to the inner wall surface (not shown) of the housing main body 3a, and a regulator holding member 7a is disposed which has the function of sending surplus fuel through this surplus fuel drainage passage 6a to the inner wall surface of the housing main body 3a and then returning it along the inner wall surface to the fuel storage tank 2a.

[0008] Therefore, in this fuel supply device, by providing the regulator holding portion 7a as described above on the underside of the lid body 8a inside the housing main body 3a, it is possible to prevent the generation of vapor in the stored fuel or disturbance in the liquid surface caused by the excess fuel discharged from the regulator 5a flowing down into the fuel storage tank 2a, thereby making it possible to avoid the occurrence of the above-mentioned problems.

[0009] However, the regulator holding member 7a used in this fuel supply device requires an excess fuel drainage path 6a that returns excess fuel to the fuel storage tank 2a along the inner wall surface of the housing main body 3a, and therefore is a relatively large molded product, which can be difficult to procure and fit into the narrow space inside the case, resulting in disadvantages in terms of cost.In addition, due to the storage and arrangement of other parts, the float 4a placed in the fuel storage tank 2a is located below the outlet of the excess fuel drainage path 6a, and there are concerns that this may affect the float 4a depending on the operating conditions.

[0010] In addition, the applicant has previously invented and filed a patent application for a fuel supply device for supplying liquid fuel stored in a fuel tank to an engine, which prevents the adverse effects caused by excess fuel flowing down from a regulator into fuel stored in a fuel tank, and enables fuel to be supplied to the engine in a stable state without the mixing of vapor or impurities (Patent Application No. 2020-147027).

[0011] As shown in Figures 6 and 7, in this invention, a vertical passage 10a extending downward from the lower end side of the return port at which the regulator 5a is located in a cover 8a that closes the upper part of the housing main body 3a and holds the regulator 5a is closed at its lower end by an upward contact surface 11a, and the surplus fuel flowing down is temporarily received by this contact surface 11a, and from a discharge port 12a formed by opening a part of the inner peripheral surface at the lower end side of the vertical passage 10a to the side, the surplus fuel is discharged sideways toward the top of a fuel receiving surface 13a provided on the inner wall surface of the housing main body 3a, and is temporarily received by the fuel receiving surface 13a before being returned to the fuel storage tank 2a along the inner wall surface of the housing main body 2a. This has less of an effect on the liquid level than the configuration shown in Figure 5 in which the fuel is returned directly to the fuel storage tank along the inner wall surface of the housing main body 2a. However, due to the arrangement of parts such as the fuel pump 1a and the float 4a, the fuel must be returned toward the float 4a, and it cannot be said that there is no effect on the float 4a at all.

[0012] In addition, this conventional fuel supply device buffers the downward momentum of surplus fuel flowing down the vertical passage 10a connected to the lid body 8a with the contact surface 11a at the lower end, converts it into a horizontal flow at the outlet 12a opening to the side of the lower end portion of the vertical passage 10a, and discharges it toward the top of the fuel receiving surface 13a installed on the inner wall surface of the housing main body 3a, which is located lower than the vertical passage 10a. However, the flow rate of the surplus fuel discharged from the regulator 5a is not constant, and it is necessary to accurately set the positional relationship between the outlet 12a opening to the side and the fuel receiving surface 13a, making it difficult to design, and since the vertical passage 10a and the outlet 12a opening to the side must be formed in the lid body 8a, not only is manufacturing difficult, but maintenance and repair are also troublesome. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] JP 2008-297941 A [Patent Document 2] JP 2016-205169 A [Patent Document 3] JP 2018-105129 A Summary of the Invention [Problem to be solved by the invention]

[0014] The present invention has an object to provide a fuel supply device that is disposed midway through a fuel supply pipe to supply liquid fuel stored in the conventional fuel tank to an engine, which uses simpler parts for easier assembly, maintenance, and repair, and which can prevent problems that arise when excess fuel from a regulator flows down into the fuel stored in a fuel storage tank, thereby enabling fuel to be supplied to the engine in a stable state without the mixing of vapor or impurities. [Means for solving the problem]

[0015] The fuel supply device of the present invention, which has been made to solve the above problems, is disposed midway through a fuel supply path leading from a fuel tank to an engine, and is composed of a housing main body forming a fuel storage tank that also serves as a reservoir tank, and a lid body that airtightly covers an opening of the housing main body. Inside the housing main body, there is provided a fuel pump that pressurizes the stored fuel, a regulator that returns surplus fuel to the fuel storage tank while regulating the pumped fuel to a predetermined pressure, and a fuel storage amount adjustment means that uses a float floating in the storage tank to maintain the liquid level of the fuel stored in the fuel storage tank at a constant level, and the fuel supply device delivers fuel at a predetermined pressure from a fuel discharge pipe provided on the lid body to supply it to the engine, and is characterized in that the regulator is held by a holding member fixed to the back surface of the lid body so that an outlet for surplus fuel is discharged to a position that avoids the operating area of ​​the float on the liquid level of the fuel storage tank.

[0016] According to the present invention, the excess fuel discharged from the regulator's outlet flows down to the liquid level of the fuel stored in the fuel storage tank, avoiding the operating area of ​​the float, thereby suppressing the shaking of the liquid level on the float side caused by the excess fuel and preventing the fuel from foaming, making it possible to supply fuel to the engine in a stable state without the introduction of vapor or impurities.

[0017] Furthermore, in the present invention, the regulator is held by a holding member fixed to the rear surface of the lid, so that attachment and detachment is easy and reliable.

[0018] Furthermore, in the present invention, when the holding member has a receiving portion with a fuel receiving surface consisting of an inclined surface that receives the excess fuel discharged from the excess fuel outlet of the regulator, and the excess fuel flowing down from the outlet is once received on the fuel receiving surface before it flows down to a predetermined position on the liquid surface, the holding member once receives the excess fuel discharged from the excess fuel outlet of the regulator on the fuel receiving surface before it flows down to the liquid surface, so that the downward momentum of the flowing down excess fuel is cushioned and the excess fuel flows down to the liquid surface avoiding the operating area of ​​the float of the fuel stored in the fuel storage tank, thereby effectively preventing the excess fuel discharged downward from shaking the fuel liquid surface or generating vapor due to its flowing down momentum.

[0019] In particular, by adjusting the inclination angle and discharge direction of the fuel receiving surface so that the excess fuel flowing down from the discharge port is first received by the fuel receiving surface and then flows down along the inner wall surface of the fuel storage tank to the liquid surface, it is possible to more reliably prevent the discharged excess fuel from shaking the fuel liquid surface or generating vapor due to the force of its downward flow, without adding any other parts or devices.

[0020] Furthermore, in the present invention, an excess fuel drainage passage that sends excess fuel to the inner wall side of the housing body is formed in the lid body, and an upward-facing fuel receiving surface is formed in the housing body to receive fuel discharged below the end side of the excess fuel drainage passage.This ensures that the excess fuel discharged from the regulator does not directly hit the vertical inner wall surface or liquid surface of the housing body, and makes it possible to minimize the occurrence of problems associated with the flow of excess fuel downward without the need for a separate regulator holding member as in the conventional example, thereby achieving a stable supply of fuel without increasing the number of parts or the effort required for assembly.

[0021] In addition, in the present invention, when the holding member has a horizontal surface and an inclined surface connected downward on one side of the horizontal surface, and the side surface is formed in an angle shape, the outer surface of the horizontal surface serves as the holding surface of the regulator and the mounting surface for the rear surface of the lid, and the exhaust port of the regulator for surplus fuel is exposed in a through hole formed in the horizontal surface, and the inner surface of the inclined surface side located below the horizontal surface serves as the fuel receiving surface, there is no need to form an excess fuel exhaust path using hard synthetic resin and mold it into a complex shape as in the conventional holding members, and the fuel receiving surface can be formed from a plate-shaped metal. It can be formed from a hard synthetic resin material, which allows for cost reduction, and the regulator can be easily and securely attached to the lid. The inclined surface with a specified inclination and direction ensures that the discharged surplus fuel does not directly hit the vertical inner wall surface of the housing body or the liquid surface. Instead, the fuel is received by the fuel receiving surface and then flows down the inner wall surface of the fuel storage tank to the liquid surface. This makes it possible to effectively prevent the discharged surplus fuel from shaking the fuel liquid surface or generating vapor due to the force of its downward flow, without the need for any additional parts or devices. Effect of the Invention

[0022] As described above, according to the present invention, the regulator has its excess fuel outlet held by a retaining member fixed to the back surface of the lid, avoiding the operating area of ​​the float on the liquid surface of the fuel storage tank. Therefore, the excess fuel discharged from the regulator outlet flows down to the liquid surface of the fuel stored in the fuel storage tank, avoiding the operating area of ​​the float, thereby suppressing shaking of the liquid surface on the float side caused by excess fuel and preventing fuel from foaming, and making it possible to supply fuel to the engine in a stable state without vapor or impurities being mixed in. [Brief description of the drawings]

[0023] [Figure 1] 1 is an external perspective view showing a preferred embodiment of the present invention; [Diagram 2] FIG. 2 is a partial cross-sectional view taken along line AA of the embodiment shown in FIG. [Diagram 3]2A and 2B are perspective views showing the main parts of the embodiment shown in FIG. 1, in which FIG. 2A shows the main parts in an exploded state and FIG. [Figure 4] FIG. 2 is a plan view of the embodiment shown in FIG. 1 with a cover removed. [Diagram 5] FIG. [Figure 6] FIG. 11 is a partial vertical sectional view showing a main portion of a different conventional example. [Figure 7] FIG. 7 is a cross-sectional view taken along line BB of the conventional example shown in FIG. 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Preferred embodiments of the present invention will now be described in detail with reference to the drawings.

[0025] 1 to 4 show a preferred embodiment of the present invention, in which a fuel supply device 1 has a lid 2 that airtightly covers the opening of a housing body 12 that is bottomed and has a fuel storage tank 11 formed therein, and has a fuel pump 4 that introduces fuel stored in the fuel storage tank 11 located within the housing body 12 through an inlet 31 and discharges it from an outlet 32 ​​formed in the lid 2 of the housing body 12.

[0026] The fuel pump 4 is disposed with an electrode portion 41 formed on the upper end of the lid 2 protruding therefrom, enabling electrical connection to the outside.

[0027] In addition, a float 5 having an adjustment mechanism for determining the position of a liquid level 51 of the fuel stored in the fuel storage tank 11 is disposed in the fuel storage tank 11 .

[0028] Furthermore, in the fuel storage tank 11, a regulator 6 is provided which has a pressure regulating port 62 connected to a fuel discharge pipe (not shown) formed in the lid 2 of the housing body 12 above an internal pressure regulating member 61 and an outlet 63 below the pressure regulating member 61, and is held in a position above the fuel pump 4 in the fuel storage tank 11 by a holding member 7 fixed to the lid 2.

[0029] To explain in more detail, the retaining member 7 used to hold the regulator 6 in this embodiment is formed, for example, by bending a metal plate or by molding from a hard synthetic resin, and has a horizontal surface 71 and an inclined surface 73 connected downward at one side 72 of the horizontal surface 71, with the side formed in an angle shape. The regulator 6 is attached to the back surface of the lid body 2 by using a fastening member 8 such as a set screw or rivet pin inserted from the inner surface (the lower surface as shown) of another through hole 75 formed in the horizontal surface 71 as the retaining surface for the regulator 6.

[0030] In this embodiment, the inclined surface 73 of the holding member 7 facing the exhaust port 63 for the surplus fuel serves as a fuel receiving surface 76 for the surplus fuel from the exhaust port 63 in the regulator 6 disposed above it.

[0031] Fuel supply device 1, which is this embodiment having the above-mentioned configuration, is attached to an engine, a vehicle body, or the like (not shown) via mounting portion 13 protruding from housing main body 12, and fuel from a fuel tank (not shown) is introduced into fuel storage tank 11 through suction port 31 formed in lid body 2 by fuel pump 4, and is stored in fuel storage tank 11 up to a predetermined liquid level 51 by float 5, and at the same time, fuel pump 4 discharges the fuel in fuel storage tank 11 from discharge port 32 to the engine.

[0032] When the fuel hydraulic pressure in the discharge port 32 is higher than a predetermined value, the regulator 6 is actuated to cause excess fuel to flow out of a pressure adjustment port 62 connected to a fuel supply pipe (not shown) to an exhaust port 63 and return it to the fuel storage tank 11, thereby supplying fuel at the predetermined pressure to the engine.

[0033] In particular, this embodiment differs in that when excess fuel flows out of regulator 6 through outlet 63 and is returned to fuel storage tank 11, regulator 6 is held by a novel holding member 7 that has a structure completely different from that of the conventional embodiment.

[0034] That is, in this embodiment, the retaining member 7 is positioned facing the opposite side of the float 5 so that the excess fuel discharged from the outlet 63 of the regulator 6 flows down to the liquid level 51 on the opposite side, avoiding the operating area of ​​the float 5. This suppresses the shaking of the liquid level 51 on the float side caused by the excess fuel returned from the outlet 63, preventing the fuel from foaming, and making it possible to supply fuel to the engine in a stable state without the introduction of vapor or impurities.

[0035] In addition, in the fuel supply device 1 of this embodiment, the holding member 7 has a receiving portion having a fuel receiving surface 76 consisting of an inclined surface 73 that receives the surplus fuel discharged from the surplus fuel outlet 63 of the regulator 6. Therefore, as shown by the dotted black arrow in FIG. 3, the surplus fuel flowing down from the outlet 63 is not allowed to flow directly onto the liquid level 51 of the fuel stored in the fuel storage tank 11, but is first received by the inclined surface 73 and then allowed to flow down to a predetermined position on the liquid level. The downward momentum of the flowing down surplus fuel is cushioned, avoiding the operating area of ​​the float of the fuel stored in the fuel storage tank, and flows down to the liquid level 51, for example, via the inner surface of the housing main body 12, as shown by the dotted black arrow in FIG. 4. This makes it possible to extremely effectively prevent the surplus fuel discharged downward from shaking the liquid level 51 of the fuel or generating vapor due to its flowing down momentum.

[0036] In addition, the retaining member 7 of the regulator 6 of this embodiment has a very simple structure having a horizontal surface 71 and an inclined surface 73 connected downward on one side 72 of the horizontal surface 71, and the side surface is formed in an angle shape. There is no need to form an excess fuel discharge path using hard synthetic resin and mold it into a complex shape as in the conventional retaining members, and it can be easily manufactured with a simple structure by simply bending a metal plate or a hard synthetic resin plate, and it is not costly. In particular, the regulator 6 can be easily attached to the lid body 2 on the horizontal surface 71, and no other parts are required as in the conventional case. As shown by the black dotted arrow in Figures 3 and 4, the inclined surface 73 alone temporarily receives the excess fuel flowing down from the discharge port 63, and while cushioning the downward momentum, the inclination angle is used to allow the fuel stored in the fuel storage tank 11 to flow down to the liquid level 51 that avoids the operating area of ​​the float 5 of the fuel stored in the fuel storage tank 11, such as the inner wall of the housing main body 12, for example.

[0037] Furthermore, the angle and distance of flow to the stored liquid surface can be adjusted simply by changing the inclination angle and length of the inclined surface 73, making it versatile for use with fuel supply devices of different storage capacities and shapes. [Explanation of symbols]

[0038] 1 fuel supply device, 2 lid body, 4 fuel pump, 5 float, 6 regulator, 7 holding member, 8 fastening member, 11 fuel storage tank, 12 housing body, 13 mounting portion, 21 storage recess, 31 suction port, 32 discharge port, 41 electrode portion, 51 liquid level, 61 pressure adjustment member, 62 pressure adjustment port, 63 discharge port, 71 horizontal surface, 72 one side, 73 inclined surface, 74 through hole, 75 through hole, 76 fuel receiving surface

Claims

1. A fuel supply device that is disposed in a fuel supply passage extending from a fuel tank to an engine and delivers fuel at a predetermined pressure to the engine, A housing body having a fuel storage tank that also serves as a reservoir tank; a cover that airtightly covers the opening of the housing body and has a fuel discharge port; a fuel pump that pumps the fuel stored in the fuel storage tank and delivers it from the discharge port; a regulator having an outlet for excess fuel, the regulator adjusting the pressure of the fuel pumped from the fuel pump to a predetermined pressure and returning the excess fuel from the outlet to the fuel storage tank; a fuel storage amount adjusting means for maintaining the liquid level of the fuel stored in the fuel storage tank at a constant level using a float that is placed in the fuel storage tank; a holding member fixed to a back surface of the lid body and holding the regulator such that the excess fuel flows down to a position on the liquid surface of the fuel storage tank that avoids an operating area of ​​the float, The holding member has a horizontal surface having a through hole and an inclined surface extending downward from one side of the horizontal surface, the horizontal surface is configured such that an outer surface thereof serves as a holding surface for the regulator and a mounting surface for a rear surface of the lid body, and the through hole is configured such that the outlet of the regulator is exposed; the inclined surface has an inner surface serving as a fuel receiving surface located below the through hole, and the excess fuel returned from the outlet of the regulator is once received by the fuel receiving surface and then flows down to a position on the liquid surface of the fuel storage tank that avoids an operating area of ​​the float. A fuel supply device comprising:

2. A fuel supply device as described in claim 1, characterized in that the excess fuel returned from the outlet of the regulator is first received by the fuel receiving surface and then flows down along the inner wall surface of the fuel storage tank to a position avoiding the operating area of ​​the float on the liquid surface.

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