JP2008232076A - Fuel supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel supply device capable of improving sucking efficiency of a jet pump. <P>SOLUTION: This device is provided with a fuel pump sucking fuel in a chamber and feeding the same to a fuel supply passage, a return passage in which fuel discharged from a first pressure control valve controlling fuel pressure in the fuel supply passage flows, the jet pump J1 transferring fuel in the fuel tank by jetting fuel supply from the return passage into a throat part 41 as drive fluid, a second pressure control valve R1 controlling fuel pressure in the return passage, and a supply structure 45 supplying fuel passing the second pressure control valve R1 to the throat part 41 as drive fluid of the jet pump J1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel supply device that supplies fuel in a fuel tank to an internal combustion engine or the like.

  Conventionally, various fuel supply devices have been proposed. Patent Document 1 discloses a fuel supply device as an example, and this fuel supply device includes a fuel pump, a chamber, a fuel filter, and a regulator valve, and cleans the fuel in the fuel tank to internal combustion. Send to the institution.

  When the fuel stored in the chamber is sucked and discharged by the fuel pump, the fuel passes through the fuel filter and is then supplied to the internal combustion engine via the fuel supply passage (main fuel passage). It is distributed to what is returned to the fuel tank through a return passage by a valve.

  The regulator valve controls the fuel pressure in the fuel supply passage to control the injection pressure of the fuel injection valve of the internal combustion engine. The fuel discharged from the regulator valve is introduced into the return passage.

  The fuel that has flowed out into the return passage is supplied to a jet pump that introduces the fuel in the fuel tank into the fuel pump chamber.

The jet pump jets fuel flowing out from the return passage from the jet nozzle to the throat portion, generates a negative pressure around the inlet of the throat portion, and feeds the fuel in the fuel tank to the chamber by the negative pressure. It has become.
JP-A-2005-320884

  By the way, in such a fuel supply device, when the amount of fuel supplied to the internal combustion engine is small, that is, when the flow rate of fuel returned to the fuel tank via the regulator valve is large, the passage resistance by the jet nozzle etc. downstream of the regulator valve The pressure on the upstream side of the jet nozzle, that is, the pressure on the downstream side of the regulator valve is increased.

  Here, because of the structure of this type of regulator valve, the maximum valve opening amount is reached if the pressure on the downstream side becomes too high, and the valve body does not move even if the pressure increases further, and the regulator valve functions sufficiently. This will adversely affect the injection pressure of the fuel injection valve of the internal combustion engine. Therefore, in order to avoid such a situation, a relief valve is installed in the return passage to control the pressure on the downstream side of the regulator valve, and the pressure is prevented from becoming higher than necessary.

  However, since the fuel discharged from the relief valve is discharged into the fuel tank without going through the jet pump, fuel corresponding to the discharged fuel is used as the driving fluid supplied from the regulator valve to the jet pump. There is a problem that the suction efficiency of the jet pump decreases.

  Then, an object of this invention is to provide the fuel supply apparatus which can improve the suction efficiency of a jet pump.

  The invention described in claim 1 is provided in a fuel tank, and stores a fuel, a fuel pump that sucks the fuel in the chamber and sends it to a fuel supply passage, and a fuel pressure in the fuel supply passage. A return passage through which fuel discharged from the first pressure control valve to be controlled flows, and a jet pump for transferring the fuel in the fuel tank by jetting the fuel supplied from the return passage into the throat portion as a driving fluid A second pressure control valve for controlling the fuel pressure in the return passage, and a supply structure for supplying the fuel passing through the second pressure control valve to the throat portion as a driving fluid for the jet pump. This is a fuel supply device.

  According to a second aspect of the present invention, in the fuel supply device according to the first aspect, the jet pump includes a jet nozzle that ejects fuel supplied from the return passage into a throat portion, while the second pressure is provided. The adjustment valve has an introduction port through which fuel from the return passage is introduced, a fuel introduction chamber in which a peripheral portion of the introduction port serves as a valve seat, and the jet nozzle are provided. A valve body that is freely fitted and detachably seated on the valve seat, a fuel injection port that functions as the supply structure and that ejects fuel in the fuel introduction chamber into the throat portion, and a valve closing direction of the valve body And an urging member for urging the lens.

  According to a third aspect of the present invention, in the fuel supply device according to the first aspect, the jet pump includes a jet nozzle that ejects fuel supplied from the return passage into a throat portion, while the second pressure is provided. The regulating valve functions as the supply structure, and introduces an inlet for introducing fuel from the return passage into the jet nozzle, a valve body for opening and closing the inlet while ensuring a predetermined passage area, and the valve body. And an urging member for urging in the valve closing direction.

  According to the present invention, since the supply structure for supplying the fuel passing through the second pressure control valve to the throat portion as the driving fluid for the jet pump is provided, the suction efficiency of the jet pump can be improved.

[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. 1 is a cross-sectional view showing a schematic configuration of the fuel supply system of the present embodiment, FIG. 2 is a cross-sectional view of the fuel supply device, FIG. 3 is a developed cross-sectional view of the fuel supply device, and FIG. FIG. 5 is an enlarged cross-sectional view of a jet pump that introduces fuel in the fuel tank into the fuel pump chamber, FIG. 6 is a side view of a valve body of a relief valve incorporated in the jet pump, and FIG. These are expanded sectional views which show the operating state of the jet pump shown in FIG.

  The fuel supply device 1 of the present embodiment is applied to a system for supplying fuel to an automobile engine 60 as an internal combustion engine as shown in FIG. 1, and the fuel supply device 1 is a fuel mounted on a vehicle. It is attached to the tank 2.

  The fuel tank 2 is configured as a vertical tank having a main tank 2m and a sub tank 2s, and the fuel supply device 1 is fixed to the upper surface side of the main tank 2m and is suspended in the main tank 2m. The case 3, the chamber 4 for storing fuel, the fuel filter 5, and the fuel pump 6 that sucks the fuel in the chamber 4 and sends it to a fuel supply passage 16 to be described later are integrated.

  In the present embodiment, a regulator valve 7 (see FIG. 3) as a first pressure regulating valve is provided integrally with the fuel supply device 1, and in this embodiment, in this embodiment, fuel for supplying fuel is provided. A so-called non-return type fuel supply system is constructed in which only the pipe 8 is present and there is no return pipe from the automobile engine 60.

  As shown in FIG. 2, the case 3 has a mounting bracket 3a, a spacer 3b, and a main case 3c from the upper side. For example, after molding each of them with a resin material, they are welded and bonded together. Formed with.

  The mounting bracket 3a is mounted so as to close an opening provided on the upper surface side of the fuel tank 2, and a pipe 9 for connecting the fuel pipe 8 to the automobile engine 60 and a fuel are mounted on the upper surface of the mounting bracket 3a. A connector 10 is provided for energizing electrical components in the fuel tank 2 such as the pump 6.

  The spacer 3b is joined to the lower surface of the mounting bracket 3a. The main case 3c joined to the lower surface of the spacer 3b is integrated with the fuel supply device 1 such as the fuel pump 6 and the fuel filter 5 for purifying the fuel. Various parts to be converted are mounted, and fuel passages between the parts are formed. The fuel pump 6 sucks the fuel in the chamber 4 through the suction filter 12.

  As shown in FIG. 3, a plurality of fuel passages 16, 17, 19, 21, 22 are formed in the main case 3c. Here, the fuel passage 16 is a fuel supply passage for supplying fuel to the automobile engine 60, the fuel passage 17 is a branch passage, and the fuel passage 19 is a regulator that controls the fuel pressure in the fuel passage (fuel supply passage) 16. This is a return passage through which fuel discharged from the valve 7 flows. Hereinafter, these fuel passages 16, 17, 19 are also referred to as a fuel supply passage 16, a branch passage 17, and a return passage 19. Further, as shown in FIG. 4, these fuel passages 16, 17, 19, 21, and 22 are collectively suitable on one side (the right side) of the region where the fuel tank and the fuel filter 5 are formed (the left side in FIG. 4). The main case 3c, and thus the fuel supply device 1 is prevented from increasing in the radial direction.

  Further, a bottomed circular hole 13 is formed in the main case 3c adjacent to the fuel pump 6 so as to extend downward with the upper surface as an opening, and the fuel filter 5 is inserted into the bottomed circular hole 13. . The inlet of the fuel filter 5 communicates with the discharge port 6a of the fuel pump 6 through a fuel passage 14 extending in the lateral direction.

  The bottom region of the bottomed circular hole 13 serving as the outlet of the fuel filter 5 communicates with the fuel supply passage 16 via the fuel passage 15 extending in the lateral direction. The fuel supply passage 16 is connected to the spacer 3b. The mounting bracket 3a is also provided so as to penetrate therethrough, and communicates with the inside of the pipe 9 of the mounting bracket 3a at its upper end.

  The fuel supply passage 16 communicates with a branch passage 17 on the lower side, and the branch passage 17 is connected to an upper bottom portion of a hole 18 formed in a lower end of the main case 3c. The regulator valve 7 is fitted into the hole 18 from below and fixed.

  The upper bottom portion of the hole 18 further communicates with a return passage 19, and the upper end portion of the return passage 19 communicates with a fuel reservoir 20 formed at the joint surface between the spacer 3 b and the main case 3 c.

  Then, the fuel discharged from the fuel pump 6 is introduced into the fuel filter 5 from the discharge port 6a through the fuel passage 14, passes through the fuel filter 5 from the bottom to the bottom, and is then purified. After that, the fuel supply passage 16 is reached.

  At this time, the fuel in the fuel supply passage 16 is supplied to the fuel injection valve of the automobile engine 60 via the pipe 9 and the fuel pipe 8 (see FIG. 1), and via the regulator valve 7 and the return passage 19. Then, it is distributed to the fuel tank 2 (inside the chamber 4). In the present embodiment, since it is a non-return system, all the fuel discharged from the fuel pump 6 that is not supplied to the automobile engine 60 side flows into the regulator valve 7 and the fuel discharged from the regulator valve 7 is The fuel is introduced into the fuel reservoir 20 through the return passage 19.

  Two fuel passages 21 and 22 communicate with the fuel reservoir 20. One fuel passage 21 of the fuel passages 21 and 22 is provided with a first jet pump J1 for supplying the fuel in the main tank 2m to the chamber 4, and the other fuel passage 22 is provided in the sub tank 2s. A second jet pump J2 for supplying fuel to the main tank 2m is provided. The first and second jet pumps J1 and J2 operate using the fuel supplied from the return passage 19 as a driving fluid, and transfer the fuel in the fuel tank 2.

  One fuel passage 21 communicates with a fuel passage 23 formed in the chamber 4. Specifically, a pipe 24 projecting downward from the fuel reservoir 20 of the main case 3 c is provided from the bottom surface of the chamber 4. It is inserted into a pipe 25 projecting upward, and the insides of these pipes 24, 25 serve as fuel passages 21, 23.

  Here, a through hole 26 is formed at the lower end of the pipe 25, and the nozzle unit 27 of the jet pump J1 is fitted into the through hole 26 from below. The nozzle unit 27 is provided with a cylindrical jet nozzle 27 a that ejects the fuel supplied from the return passage 19. The return fuel ejected from the jet nozzle 27a is introduced into the throat portion 41 of the jet pump J1 and generates a negative pressure around the inlet of the throat portion 41.

  Then, the generated negative pressure sucks the fuel in the main tank 2 m from the fuel introduction port 41 a of the throat portion 41, and feeds the sucked fuel in the tank together with the return fuel ejected from the nozzle unit 27 into the chamber 4. It is supposed to be.

  A coil spring 28 as an urging member is wound around the outer periphery of the pipe 24 between the root of the pipe 24 and the tip of the pipe 25, and the chamber 4 allows the chamber 4 to be fuel tank. 2 can be pressed against the bottom surface.

  The other fuel passage 22 is provided in a pipe 29 extending downward from the fuel reservoir 20, and the jet nozzle 30 of the second jet pump J2 is fitted into the opening thereof. The downstream side is the fuel passage 22.

  The jet port 30 a of the jet nozzle 30 communicates with the introduction pipe 33 to which the fuel tube 32 from the sub tank 2 s is connected via the fuel passage 31, while the lower end of the fuel passage 22 opens to the inside of the chamber 4. Yes.

  Accordingly, when the return fuel in the fuel reservoir 20 is ejected from the ejection port 30a of the jet nozzle 30, a negative pressure is generated around the inlet of the pipe 29 as the throat portion, and the generated negative pressure causes the negative pressure from the fuel passage 31. The fuel in the sub tank 2 s is sucked and fed into the chamber 4 from the fuel passage 22.

  Here, in the present embodiment, as shown in FIG. 5, the first jet pump J1 discharges the excess pressure in the fuel reservoir 20 connected to the return passage 19 and ejects the released fuel to the throat portion 41. A relief valve R1 as a second pressure regulating valve is integrally provided. The relief valve R1 thus installed controls the fuel pressure in the return passage 19.

  The relief valve R <b> 1 is incorporated in the nozzle unit 27. As shown in FIG. 5, the relief valve R 1 includes a fuel introduction chamber 42 in which return fuel from the return passage 19 (fuel reservoir 20) is introduced and a peripheral portion of the introduction port 43 serves as a valve seat 44. A valve body 37 movably fitted in the fuel introduction chamber 42 and seated on and off the valve seat 44, a fuel outlet 45 for ejecting the fuel in the fuel introduction chamber 42 into the throat portion 41, and the valve body 37 are provided. And a spring 38 as a biasing member that biases in the valve closing direction. Here, in the present embodiment, the fuel outlet 45 functions as a supply structure that supplies the fuel passing through the relief valve R1 to the throat portion 41 as the driving fluid of the jet pump J1.

  The fuel introduction chamber 42 is formed in a substantially cylindrical tubular storage portion 36 protruding from the housing 40 of the nozzle unit 27, and a valve body 37 formed in a bottomed cylindrical shape in the cylindrical storage portion 36 is a cylinder. An appropriate gap is provided between the inner periphery of the cylindrical storage portion 36 and loosely fitted, and a lid 39 is crimped and fixed to the opening of the distal end of the cylindrical storage portion 36.

  A jet nozzle 27 a that communicates with the introduction port 43 projects from the center of the bottom of the valve body 37. The front end of the jet nozzle 27a is inserted through an opening 39a formed in the center of the lid 39 with an appropriate gap, and the gap between the jet nozzle 27a and the opening 39a is connected to the fuel jet 45. It has become.

  The spring 38 is contracted between the bottom of the valve body 37 and the lid 39, and the bottom of the valve body 37 is brought into close contact with the valve seat 44 by the urging force of the spring 38.

  At this time, as shown in FIG. 6, a plurality of protrusions 37 a are provided at the tip of the valve body 37, and return fuel can pass through between the protrusions 37 a even when the valve body 37 abuts against the lid body 39. It is like that.

  Therefore, in the first jet pump J1, when the fuel pressure in the return passage 19 that has passed through the regulator valve 7 is low, the valve element 37 of the relief valve R1 is urged by the urging force of the spring 38 as shown in FIG. 44, the return fuel discharged from the fuel reservoir 20 passes through the inlet 43 through the fuel passage 23 and is jetted from the jet nozzle 27 a to the throat portion 41. Negative pressure is generated around.

  On the other hand, when the fuel pressure in the return passage 19 becomes higher than the set pressure determined by the urging force of the spring 38, the fuel pressure acts on the bottom of the valve body 37 as shown in FIG. The body 37 is pushed out against the urging force of the spring 38 to form a gap between the bottom of the valve body 37 and the valve seat 44, and the return fuel flowing in from the gap is stored in the outer periphery of the valve body 37 and the tubular storage. It passes through a gap between the inner periphery of the portion 36 and is introduced into the fuel introduction chamber 42, and the fuel in the fuel introduction chamber 42 is ejected from the fuel ejection port 45 into the throat portion 41.

  According to the fuel supply device 1 of the present embodiment described above, the relief that releases the excess pressure in the return passage 19 (fuel reservoir 20) to the first jet pump J1 and jets the released fuel to the throat portion 41. Since the valve R1 is configured, the installation space for the relief valve R1 can be reduced, so that an increase in the size of the fuel supply device 1 can be avoided.

  Further, the excess pressure in the return passage 19 is released by the relief valve R1, thereby preventing the pressure on the downstream side of the regulator valve 7 from being excessively increased, and the control (pressure regulation) function of the regulator valve 7 is impaired. In addition, it is possible to improve the suction efficiency of the jet pump J1 by generating a large negative pressure around the inlet of the throat portion 41 by ejecting the fuel released from the relief valve R1 to the throat portion 41. Can do.

  Further, in the present embodiment, the relief valve R1 can be accommodated in the nozzle unit 27 in a compact manner, and the assembly work of the fuel supply device 1 can be further simplified.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is an enlarged cross-sectional view of a jet pump that introduces fuel in a tank into a fuel pump chamber, and FIG. 9 is an enlarged cross-sectional view showing an operating state of the jet pump shown in FIG. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  The fuel supply device of the present embodiment has basically the same configuration as the fuel supply device 1 of the first embodiment, and the first jet that supplies the fuel in the main tank 2m to the chamber 4 (see FIG. 3). A relief valve R2 that discharges excess pressure in the fuel reservoir 20 connected to the return passage 19 to the pump J1 and jets the released fuel to the throat portion 41 is configured. The relief valve R2 installed in this way controls the fuel pressure in the return passage 19.

  The relief valve R2 is incorporated in the nozzle unit 27 as in the first embodiment. As shown in FIG. 8, the relief valve R2 is a conical valve body that opens and closes an introduction port 43 through which return fuel from the return passage 19 (fuel reservoir 20) is introduced into the jet nozzle 27b while ensuring a prescribed passage area. 46 and a spring 38A as a biasing member that biases the valve body 46 in the valve closing direction. Here, in this embodiment, the introduction port 43 functions as a supply structure that supplies the fuel that passes through the relief valve R2 to the throat portion 41 as the driving fluid of the jet pump J1.

  The jet nozzle 27 b is integrally projected as a cylindrical shape from the peripheral portion of the introduction port 43 formed in the housing 40, and a storage portion 47 of the valve body 46 is formed on the side surface of the housing 40 facing the introduction port 43. The

  The storage portion 47 is formed in a bottomed cylindrical shape having a bottom portion 39, while the valve body 46 is formed by expanding the diameter of a guide portion 48 that is closely fitted in the storage portion 47 so as to be slidable. Then, a spring 38A is contracted between the inside of the stepped portion 48a whose diameter has been enlarged and the bottom portion 39, and the valve body 46 is urged by the spring 38A in a direction to close the inlet 43 serving as a valve seat. . An air vent hole 39 a is formed in the bottom 39.

  In addition, a locking portion 47a that engages with a stepped portion 48a of the guide portion 48 to prevent the valve body 46 from popping out is formed at the open side end portion (left end portion in the figure) of the storage portion 47. Even when the valve body 46 is closed by the urging force of the spring 38 </ b> A by the locking portion 47 a, a gap that allows a minimum fuel passage is formed between the valve body 46 and the introduction port 43. It has become so.

  Therefore, according to the fuel supply device of the present embodiment, when the pressure in the return passage 19 (fuel pool 20) is low, the prescribed passage in which the return fuel in the return passage 19 is secured between the valve body 46. The fuel that has flowed into the inlet 43 from the area is jetted into the throat portion 41 from the jet nozzle 27b and functions as a normal jet pump.

  On the other hand, when the pressure in the return passage 19 becomes higher than the set value, the valve body 46 is pushed into the storage portion 47 against the urging force of the spring 38A, and the introduction port 43 is greatly opened, so that the jet pump J1 is opened. The fuel flowing in, that is, the fuel flowing into the jet nozzle 27b can be increased. For this reason, the amount of fuel flowing in from the jet nozzle 27b into the throat portion 41 increases, and the negative pressure around the inlet of the throat portion 41 can be increased, and the suction efficiency of the jet pump J1 can be increased. Can be improved.

  The present invention is not limited to the above embodiment, and various other embodiments can be adopted without departing from the gist of the present invention. For example, in the first and second embodiments described above, the case where the relief valves R1 and R2 are applied to the first jet pump J1 that transfers the fuel in the main tank 2m to the chamber 4 is illustrated, but the present invention is not limited thereto. The relief valves R1 and R2 may be applied to the second jet pump J2 that transfers the fuel in the sub tank 2s to the main tank 2m without any problem. In this case, the suction efficiency of the second jet pump J2 can be increased while ensuring the function of the regulator valve 7.

1 is a cross-sectional view showing a schematic configuration of a fuel supply system according to a first embodiment of the present invention. Sectional drawing of the fuel supply apparatus concerning the 1st Embodiment of this invention. 1 is a developed cross-sectional view of a fuel supply device according to a first embodiment of the present invention. The top view of the main case of the fuel supply apparatus concerning the 1st Embodiment of this invention. The expanded sectional view of the jet pump which introduces the fuel in the fuel tank in the 1st Embodiment of this invention into the chamber of a fuel pump. The side view of the valve body of the relief valve integrated in the jet pump in the 1st Embodiment of this invention. The expanded sectional view which shows the operation state of the jet pump shown in FIG. The expanded sectional view of the jet pump which introduces the fuel in the tank concerning the 2nd Embodiment of this invention into the chamber of a fuel pump. The expanded sectional view which shows the operating state of the jet pump shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fuel supply apparatus 2 ... Fuel tank 6 ... Fuel pump 7 ... Regulator valve (1st pressure regulation valve)
16 ... Fuel supply passage 19 ... Return passage 27a, 27b ... Jet nozzle 37, 46 ... Valve body 38, 38A ... Spring (biasing member)
41 ... Throat part 43 ... Inlet (supply structure)
44 ... Valve seat 45 ... Fuel outlet (supply structure)
J1 ... Jet pump R1, R2 ... Relief valve

Claims (3)

A chamber provided in the fuel tank and storing fuel;
A fuel pump that sucks the fuel in the chamber and sends it to a fuel supply passage;
A return passage through which fuel discharged from a first pressure control valve that controls the fuel pressure in the fuel supply passage;
A jet pump that transfers the fuel in the fuel tank by ejecting the fuel supplied from the return passage as a driving fluid into the throat portion;
A second pressure control valve for controlling the fuel pressure in the return passage;
A supply structure for supplying fuel passing through the second pressure control valve to the throat portion as a driving fluid of the jet pump;
A fuel supply device comprising: While the jet pump includes a jet nozzle that jets fuel supplied from the return passage into the throat portion,
The second pressure regulating valve is
A fuel introduction chamber having an introduction port through which fuel from the return passage is introduced, and a peripheral portion of the introduction port serving as a valve seat;
A valve body provided with the jet nozzle, movably fitted in the fuel introduction chamber, and detachably seated on the valve seat;
A fuel jet that functions as the supply structure and jets the fuel in the fuel introduction chamber into the throat portion;
A biasing member that biases the valve body in a valve closing direction;
The fuel supply device according to claim 1, further comprising: While the jet pump includes a jet nozzle that jets fuel supplied from the return passage into the throat portion,
The second pressure regulating valve is
An inlet that functions as the supply structure and introduces fuel from the return passage into the jet nozzle;
A valve body that opens and closes the inlet while ensuring a prescribed passage area;
A biasing member that biases the valve body in the valve closing direction;
The fuel supply device according to claim 1, further comprising:

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