JP2010216433A - Fuel supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel supply system promptly increasing pressure when a fuel pump is restarted, and also simplifying a structure. <P>SOLUTION: A variable flow rate type is employed for the fuel pump 20, and a check valve 23 is provided to the delivery port 22 of the fuel pump. A branch passage 42 is branched from a branch point 41 in the middle of a fuel supply passage 40, and a jet pump 50 is provided in the branch passage 42. The injection nozzle 51 of the jet pump 50 is used as a throttle means for regulating fuel pressure. A remaining pressure holding valve 70 is provided on a passage in front of the injection nozzle 51. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fuel supply device that supplies liquid fuel to an internal combustion engine by a fuel pump, and in particular, sucks fuel outside a fuel holding chamber by driving a jet pump with surplus fuel discharged from the fuel pump. The present invention relates to a fuel supply device that replenishes the fuel holding chamber.

  FIG. 7 shows a configuration of a conventional fuel supply apparatus described in Patent Document 1, for example.

  This fuel supply apparatus includes a variable flow rate fuel pump 220 that delivers fuel to an internal combustion engine, a fuel holding chamber 210 that holds fuel to be sucked by the fuel pump 220, and fuel discharged from the fuel pump 220 as an internal combustion engine. A fuel supply passage 240 that feeds into the engine, and a branch passage 242 that branches off from a branch point 241 provided in the middle of the fuel supply passage 240 and returns surplus fuel out of the fuel pump 220 to the fuel holding chamber 210. The surplus fuel introduced into the branch passage 242 is injected from the injection nozzle, and the fuel in the sub tank 260 outside the fuel holding chamber 210 is used by utilizing the negative pressure generated by the injection. A jet pump 250 that sucks in and discharges the fuel into the fuel holding chamber 210 together with the injected fuel; A fuel pressure in the fuel supply passage 240 between the fuel pump 210 and the internal combustion engine after stopping the fuel pump 210 while allowing the fuel to be supplied from the fuel pump 220 to the internal combustion engine. And a pressure holding valve 230 for prohibiting the flow of fuel from the internal combustion engine to the branch point 241 when the value is equal to or less than a predetermined value.

  As shown in FIGS. 8A and 8B, the pressure holding valve 230 includes a first valve body 234 that opens and closes the outlet 233, and a first valve body inside a valve body 231 having an inlet 232 and an outlet 233. A spring 235 that biases the outlet 234 in the direction of closing the outlet 233 is incorporated, and a second valve body 236 that functions as a check valve is incorporated in the first valve body 234.

  When the fuel pump 220 is driven, the pressure holding valve 230 is configured such that, as shown in FIG. 8A, the first valve body 234 is in the closed position, but the second valve body 236 is pushed by the fuel pressure. Therefore, the fuel flows in the direction of the arrow from the inlet 232 to the outlet 233 because it moves to the open position.

  On the other hand, when the fuel pump 220 is stopped, as shown in FIG. 8A, the pressure on the inlet 231 side is released, and the second valve body 236 is moved to the closed position by the pressure on the outlet 233 side. Accordingly, the first valve body 234 moves to the open position, so that the fuel flows from the outlet 233 side to the inlet 232 side as indicated by an arrow.

  When the pressure on the outlet 233 side becomes equal to or lower than the valve closing pressure due to the urging force of the spring 235, the first valve body 234 returns to the closed position while the second valve body 236 remains in the closed position, and the pressure holding valve 230 is closed.

JP 2004-197718 A

  By the way, in the conventional fuel supply apparatus described in Patent Document 1, since the pressure holding valve 230 is provided downstream of the branch point 241 set in the middle of the fuel supply passage 240, the fuel pump 220 is stopped. When the branch passage 242 becomes free and the remaining amount of fuel in the fuel holding chamber 210 is small, the fuel escapes from the branch passage 242 and there is a problem that the pressure rise is delayed when the fuel pump 220 is restarted. .

  A first valve body 234 for holding pressure is incorporated in the valve body 231 of the pressure holding valve 230, and a second valve body 236 that functions as a check valve is incorporated in the first valve body 234. As a result, the structure is complicated.

  Accordingly, an object of the present invention is to provide a fuel supply device that can accelerate the pressure increase when the fuel pump is restarted and that has a simplified structure.

  In the present invention, the fuel pump is of a variable flow rate type, a check valve is provided on the discharge port side of the fuel pump, and the jet nozzle of the jet pump provided in the branch passage is used to adjust the fuel pressure. This is characterized in that a residual pressure holding valve is provided on the passage in front of the injection nozzle.

  According to the present invention, since the injection nozzle of the jet pump is used as the throttle means, the fuel pressure can be controlled by controlling the discharge flow rate of the fuel pump. In addition, a check valve is provided on the discharge port side of the fuel pump, and residual pressure holding means is provided in the passage in front of the jet nozzle of the jet pump, so that the fuel remaining in the fuel supply passage and branch passage when the fuel pump is stopped. The pressure set by the pressure holding valve can be maintained, and the pressure increase when the fuel pump is restarted can be accelerated. Further, since the check valve and the residual pressure holding valve are provided at different positions, the structure can be simplified.

It is a side view of the principal part of the fuel supply apparatus of embodiment of this invention. It is sectional drawing of the fuel supply module in the fuel supply apparatus. It is sectional drawing seen from the direction different from FIG. 2 of the fuel supply module. It is an enlarged view of the S section in FIG. It is TT arrow sectional drawing of FIG. It is a systematic diagram which shows schematically the structure of the fuel supply apparatus of the embodiment. It is a schematic block diagram of the conventional fuel supply apparatus. FIG. 2 is a configuration diagram of a pressure holding valve incorporated in the fuel supply device, wherein (a) is a cross-sectional view showing a state when the fuel pump is driven, and (b) is a cross-sectional view showing an initial state when the fuel pump is stopped. is there.

  Hereinafter, a fuel supply device according to an embodiment of the present invention will be described with reference to the drawings.

  1 is a side view of the main part of the fuel supply apparatus of the embodiment, FIG. 2 is a cross-sectional view of the fuel supply module in the fuel supply apparatus, and FIG. 3 is viewed from a different direction from FIG. 4 is an enlarged view of a portion S in FIG. 3, FIG. 5 is a cross-sectional view taken along the line TT in FIG. 4, and FIG. 6 is a system diagram schematically showing the configuration of the fuel supply device of the embodiment. .

  As shown in FIG. 1, a fuel supply module 10 that is a main part of the fuel supply apparatus of the embodiment is attached to the fuel tank 1. The fuel supply module 10 includes an upper case 11 having a flange 11a, and a lower case 12 provided by being divided below the upper case 11. The fuel supply module 10 is attached to the fuel tank 1 by fitting the upper case 11 into the opening 2 in the upper wall of the fuel tank 1 and fixing the flange 11a to the upper wall. All are accommodated inside the fuel tank 1.

  As shown in FIG. 2, a variable flow rate having a suction port 21 at the lower end and a discharge port 22 (the symbol indicates the vicinity of the suction port or the discharge port) at the upper end on the lower surface of the upper case 11. A fuel pump 20 of the type (that is, a fuel pump equipped with variable flow rate means) is attached. The fuel pump 20 is for sending liquid fuel to the internal combustion engine, and a suction filter 28 for filtering the intake fuel is attached to the suction port 21.

  The discharge port 22 of the fuel pump 20 is provided with a check valve 23 for preventing the backflow of discharged fuel, and a relief valve 24 for releasing excessive pressure is provided in the vicinity of the discharge port 22. Yes.

  The discharge port 22 of the fuel pump 20 is connected to one end connection port 13 a of the flow path 13 formed integrally with the upper case 11 via a check valve 23. As shown in FIG. 3, the flow path 13 forms part of the fuel supply passage 40, and the other end serves as a connection port 14 of a pipe 48 (see FIG. 6) that also constitutes the fuel supply passage 40. ing.

  As shown in the system diagram of FIG. 6, the fuel supply passage 40 connects the discharge port 22 of the fuel pump 20 to the injector 100 of the internal combustion engine, and is configured as an airtight passage, and the fuel discharged from the fuel pump 20 is discharged. It can be sent to the internal combustion engine. A fuel pressure sensor 102 that measures the fuel pressure is provided in the middle of the fuel supply passage 40.

  Further, as shown in FIG. 3, a filter 25 is interposed in the downstream portion of the flow path 13 formed in the upper case 11, and on the flow path 13 on the downstream side of the filter 25 (in the middle of the fuel supply path 40). Equivalent) is provided with a branch point 41 connected to the branch passage 42.

  The lower case 12 is mainly configured as a fuel holding chamber 30 having an upper surface opened and side and bottom surfaces defined by an outer wall 31.

  The fuel holding chamber 30 always holds the fuel to be sucked by the fuel pump 20 regardless of the posture of the vehicle or the like, and the lower end portion (suction port 21) of the fuel pump 20 is always in the fuel holding chamber 30. It is provided to be immersed in the fuel.

  Further, another flow path 35 is provided at a position along the outer wall 31 on the inner side from the inner bottom of the fuel holding chamber 30.

  The bottom of the lower case 12 is provided with a recess 36 that is outside the fuel holding chamber 30 and faces the inside of the fuel tank 1, and the inside of the recess 36 is recessed at the outer periphery of the recess 36. A wall 38 for partitioning from the outside of 36 (inside the fuel tank 1) is attached.

  In addition, one end of the flow path 35 opens sideways to the recess 36, and the other end opens upward to a predetermined height position inside the fuel holding chamber 30. . In this recess 36, a jet pump 50 integrally having a residual pressure holding valve 70 described later is disposed.

  The branch passage 42 is a passage branched from a branch point 41 provided in the middle of the fuel supply passage 40, and is used for driving a part of the surplus fuel out of the fuel pump 20 for driving the jet pump. Is. The main part of the branch passage 42 is an upper pipe 15 projecting downward from the upper case 11 and a lower pipe projecting upward from the lower case 12 and slidably connected to the lower end of the upper pipe 15 in the vertical direction. 32. The flow path 35 having a throat portion 52 to be described later at the open end also corresponds to a part of the branch passage 42.

  As shown in FIGS. 1 and 3, the lower case 12 is provided to be movable in the vertical direction with respect to the upper case 11, and is provided by a spring 16 interposed between the upper pipe 15 and the lower pipe 32. It is pressed against the inner bottom of the fuel tank 1. Thus, the jet pump 50 is always immersed in the fuel in the fuel tank 1. The upper end of the spring 16 is received by the upper case 11, and the lower end is received by a spring receiver 33 attached to the upper end of the lower pipe 32, thereby urging the lower case 12 downward.

  As shown in FIG. 4, the main part of the jet pump 50 is a combination of an injection nozzle 51 and a throat part 52, and the throat part 52 is provided at the opening end facing the space 36 of the flow path 35 facing the side. The injection nozzle 51 is disposed to face the throat portion 52 with an interval so that fuel can be injected toward the throat portion 52.

  The jet pump 50 is interposed in a recess 36 provided in the middle of the branch passage 42 with a suction flow path (a space between the injection nozzle 51 and the throat portion 52) facing the fuel tank 1. In addition, surplus fuel introduced into the branch passage 42 is injected from the injection nozzle 51 toward the throat portion 52, so that the fuel outside the fuel holding chamber 30 (inside the fuel tank 1 can be obtained using the negative pressure generated by the injection. In the fuel holding chamber 30 together with the fuel injected from the injection nozzle 51.

  Next, the jet pump 50 incorporating the residual pressure holding valve 70 will be described in detail with reference to FIGS.

  The jet pump 50 has a jet pump body 60 that also serves as a valve body of the residual pressure holding valve 70. Inside the jet pump body 60, a cavity is provided in an approximately L shape, and a partition wall 64 is provided in the middle of the cavity, so that the cavity is partitioned into two rooms. One chamber is a valve chamber 63, and the other chamber is an introduction chamber 66. The partition wall 64 is provided with a first orifice (auxiliary throttle means) 65 communicating from the introduction chamber 66 to the valve chamber 63. Yes.

  The opening end of the valve chamber 63 faces the throat portion 52 described above, and the opening end 67 of the introduction chamber 66 is fitted to the lower end of the lower pipe 32 constituting the branch passage 42. The fitting portion is provided with an engaging convex portion 34 and an engaging concave portion 69. The engaging convex portion 34 and the engaging concave portion 69 are engaged with each other, whereby the jet pump body 60 is connected to the lower pipe of the lower case 12. 32 is fixed.

  A step portion 61 is provided at the opening end of the valve chamber 63, and the disc portion 56 of the positioning member 55 is fitted into the step portion 61. In this state, the positioning member 55 is fixed to the jet pump body 60 by crimping the peripheral wall tip 62 of the valve chamber 63. Instead of caulking, the positioning member 55 may be fixed to the jet pump body 60 by other means such as welding or adhesion.

  The positioning member 55 has a cylindrical boss portion 57 protruding from the front surface and the back surface of the disk portion 56 at the center of the disk portion 56, and concentric with the boss portion 57 on the back surface of the disk portion 56. A cylindrical wall 58 having a shape is integrally formed. A small hole penetrating from the inside of the valve chamber 63 to the outside is formed at the center of the boss portion 57, and the small hole serves as the injection nozzle 51 of the jet pump 50. The outer periphery of the tip of the boss portion 57 is chamfered in a tapered shape so as to correspond to the taper of the throat portion 52.

  The valve chamber 63 is provided with a valve body 71 of the residual pressure holding valve 70 so as to be positioned between the partition wall 64 and the tip of the cylindrical wall 58 of the positioning member 55 so as to be able to move between them. . The valve body 71 has an annular upright wall 72 on the back surface, and the first orifice 65 can be closed by bringing the tip of the annular upright wall 72 into contact with the partition wall 64. Yes.

  Further, a valve spring 75 that biases the valve body 71 in a direction to close the first orifice 65 is interposed between the valve body 71 and the back surface of the disc portion 56 of the positioning member 55. That is, the valve spring 71 is always urged in the closing direction by the valve spring 75.

  When the valve element 71 is pushed up against the valve spring 75, the first orifice 65 is opened, and the fuel that has passed through the first orifice 65 flows into the valve chamber 63. A second orifice (auxiliary throttle means) 59 made of a small hole or a notch is provided at the tip of the cylindrical wall 58 of the positioning member 55, and passes through the first orifice 65 to enter the valve chamber 63. The fuel that has flowed in flows through the space between the second orifice 59 and the valve spring 75 into the inner space of the cylindrical wall 58 of the positioning member 55, and is injected toward the throat portion 52 through the injection nozzle 51. It has become so.

  As described above, the residual pressure holding valve 70 is arranged on the passage before the injection nozzle 51 of the jet pump 50, and when the pressure of the fuel introduced from the fuel supply passage 40 to the branch passage 42 exceeds a predetermined value (valve spring). The valve is opened when the urging force of 75 is overcome), and the fuel is allowed to flow to the injection nozzle 51. The valve is closed when the pressure is equal to or less than a predetermined value, thereby preventing the fuel from flowing to the injection nozzle 51. It functions to maintain the fuel pressure in the supply passage 40 and the branch passage 42.

  Here, the cylindrical wall 58 of the positioning member 55 serves to regulate the displacement amount of the valve body 71 when the valve body 71 hits the tip of the cylindrical wall 58. In addition, the amount of deflection of the valve spring 75 is regulated to prevent the valve spring 75 from sagging, and also serves to prevent the fuel from flowing due to the absence of a gap between the lines of the valve spring 75.

  Further, as shown in FIG. 5, a protrusion 78 for preventing rotation is provided on the outer peripheral portion of the valve body 71, and for preventing rotation that the convex portion 78 of the valve body 71 slides on the inner peripheral wall of the jet pump body 60. The concave groove 68 is provided. The movement of the valve element 71 is guided by the slide of the convex portion 78 and the concave groove 68 when the valve is opened and closed.

  By the way, in the jet pump 50, as described above, the first orifice 65, the second orifice 59, and the third orifice (injection nozzle 51) are arranged in order from the upstream side to the downstream side. Yes. The injection nozzle 51 which is the third orifice exhibits a high throttling effect particularly as throttling means, and by having this throttling means, the discharge flow rate of the fuel pump 20 is controlled, so that the inside of the fuel supply passage 40 The fuel pressure can be adjusted. The first and second orifices 65 and 59 serve to lower the pressure of the fuel that gradually flows toward the injection nozzle 51.

  Therefore, if A is the flow cross-sectional area of the first orifice 65, B is the cross-sectional area of the second orifice 59, and C is the flow cross-sectional area of the injection nozzle 51 that is the third orifice A ≧ B The relation of ≧ C is set.

  Returning to FIG. 1, a fuel gauge 90 for detecting the fuel level is attached to the fuel holding chamber 30, and a connector 95 for external connection is insert-molded on the flange 11 a of the upper case 11. The fuel pump 20 and the fuel gauge 90 are electrically connected.

  Next, the operation will be described.

  As shown in FIG. 6, the fuel held in the fuel holding chamber 30 is sucked by the fuel pump 20, passes through the filter 25, passes through the fuel supply passage 40, and is supplied to the injector 100 of the internal combustion engine.

  At this time, as shown in FIGS. 3 and 4, a branch passage 42 is connected in the middle of the fuel supply passage 40, and surplus fuel out of the fuel pump 20 passes through the branch passage 42. Then, it is introduced into the introduction chamber 66 of the jet pump 50 incorporating the residual pressure holding valve 70.

  Here, the minimum fuel pressure at the time of driving the fuel pump 20 is set to be equal to or higher than a predetermined value at which the residual pressure holding valve 70 opens (valve closing pressure + 50 kPa), and the fuel flowing into the introduction chamber 66 1 through the orifice 65, the valve body 71 of the residual pressure holding valve 70 is pushed up (opened), passes through the gap between the second orifice 59 and the valve spring 75, and the inside of the cylindrical wall 58 of the positioning member 55. , And is injected from the injection nozzle 51 toward the throat portion 52.

  Then, due to the negative pressure generated by this injection, the surrounding fuel between the injection nozzle 51 and the throat portion 52 is sucked, and together with the surplus fuel injected from the injection nozzle 51, To the fuel holding chamber 30. That is, as long as the fuel pump 20 is driven, the fuel pump 20 ensures a pressure equal to or higher than the minimum fuel pressure, so that the residual pressure holding valve 70 is opened by the pressure, and fuel is supplied to the injection nozzle 51. The fuel holding chamber 30 is constantly refilled with the fuel.

  In this case, the pressure of the fuel in the fuel supply passage 40 gradually increases as the rotation of the fuel pump 20 is increased, and increases to a value corresponding to the discharge capacity of the fuel pump 20 and the cross-sectional area of the injection nozzle 51. To do.

  On the other hand, when the rotation of the fuel pump 20 decreases, a difference occurs between the pressure in the fuel supply passage 40 and the pressure in the fuel pump 20, and the check valve 23 provided at the discharge port 22 of the fuel pump 20 is closed. Further, the fuel flows through the residual pressure holding valve 70 according to the position of the valve body 71 of the residual pressure holding valve 70, so that the pressure in the fuel supply passage 40 decreases, and eventually according to the discharge flow rate of the fuel pump 20. Balance with the pressure.

  Therefore, by performing feedback control on the discharge flow rate of the fuel pump 20 based on the detection value of the fuel sensor 102, the pressure of the fuel supplied to the injector 100 of the internal combustion engine through the fuel supply passage 40 can be controlled only by the flow rate control of the fuel pump 20. You can adjust it.

  When the fuel pump 20 is stopped, the check valve 23 provided at the discharge port 22 of the fuel pump 20 is closed, and the fuel pressure place in the fuel supply passage 40 is shut off here. However, since the fuel is directed to the residual pressure holding valve 70 through the branch passage 42, the fuel pressure is reduced to the valve closing pressure of the residual pressure holding valve 70, and the fuel supply passage 40 and the branch passage 42 are closed by the valve closing pressure. Fuel pressure is maintained.

  For example, when the fuel pump 20 is stopped from a state in which the fuel pump 20 is driven at a fuel pressure of 600 kPa, the valve closing pressure of the residual pressure holding valve 70 is set to 200 kPa. The fuel pressure is maintained while maintaining 200 kPa.

  As described above, according to the fuel supply apparatus of the present embodiment, the pressure of the fuel in the fuel supply passage 40 can be controlled by controlling the discharge flow rate of the fuel pump 20. Therefore, by increasing the pressure of the fuel supplied to the internal combustion engine, atomization of the injector 100 at the time of starting or fully opening can be achieved, thereby improving the exhaust of the internal combustion engine. Further, by promoting the atomization of the fuel when fully opened, it is possible to increase the fuel charging efficiency into the cylinder of the internal combustion engine, and thus the output of the internal combustion engine can be expected to be improved.

  In addition, when the fuel pump 20 is stopped, the residual pressure holding valve 70 is closed at a predetermined pressure or lower, so that the fuel supply passage 40 and the branch passage 42 can be prevented from coming out of fuel. In addition, the fuel pressure in the branch passage 42 can be maintained. Therefore, the pressure increase at the time of restarting the fuel pump 20 can be accelerated, and the pumping by the jet pump 50 can be accelerated. In addition, the vapor generated in the fuel supply passage 40 due to the influence of heat or the like when the engine is stopped can be suppressed, and the heat-resistant restartability can be ensured.

  Further, the residual pressure holding valve 70 is opened even when the pressure of the fuel in the fuel supply passage 40 rises due to the influence of heat after the residual pressure holding valve 70 is once closed due to the stop of the fuel pump 20. Thus, since excessive pressure can be released, the possibility of damage to the fuel pipe or the like can be reduced.

  In addition, when the internal combustion engine is stopped, there is a request to reduce the fuel pressure as much as possible in order to ensure the oil tightness of the injector 100. Therefore, heat restartability can be ensured within the range that can meet the request. It is desirable to maintain the lowest fuel pressure.

  Further, since the minimum fuel pressure during the control of the fuel pump 20 is set to be equal to or higher than the valve closing pressure of the residual pressure holding valve 70, the jet pump 50 can be driven at all times, and the fuel holding chamber 30 is replenished with fuel. Is possible.

  Further, since the check valve 23 and the residual pressure holding valve 70 are separately provided and the residual pressure holding valve 70 is incorporated in the body 60 of the jet pump 50, the configuration can be simplified.

  Further, when the fuel pump 20 is controlled so that the pressure in the fuel supply passage 40 increases, the pressure of the fuel introduced into the jet pump 50 also becomes high, and the fuel injected from the injection nozzle 51 of the jet pump 50. However, according to the fuel supply apparatus of the present embodiment, the pressure is increased before the injection nozzle 51 of the jet pump 50. Since the first and second orifices 65 and 59 that perform the function of gradually decreasing are provided in stages, the pressure change before and after the injection nozzle 51 can be reduced, and the boiling under reduced pressure can be prevented. Can be eliminated.

  In addition, the drive source of the fuel pump 20 in the above embodiment may be a DC motor or a brushless motor.

  In the above embodiment, the fuel holding chamber 30 is disposed inside the fuel tank 1 and the fuel in the fuel tank 1 is replenished to the fuel holding chamber 30 by the jet pump 50. The fuel holding chamber 30 may be replenished by sucking the fuel with the jet pump 50.

  Moreover, although the case where the check valve 23 was provided in the discharge port 22 of the fuel pump 20 was shown in the said embodiment, the check valve 23 is downstream from the discharge port 22 of the fuel pump 20, and is branched. Any position on the fuel supply passage 40 upstream from the point 41 may be used.

10 Fuel supply module (fuel supply device)
20 Fuel Pump 21 Suction Port 22 Discharge Port 23 Check Valve 30 Fuel Holding Chamber 40 Fuel Supply Passage 41 Branch Point 42 Branch Passage 50 Jet Pump 51 Injection Nozzle 52 Throat 59 59 First Orifice 65 First Orifice 70 Remaining Pressure Holding Valve 71 Valve body 100 Injector (internal combustion engine)

Claims (3)

A fuel pump for delivering fuel to the internal combustion engine;
A fuel holding chamber for holding fuel for suction by the fuel pump;
A fuel supply passage for sending the fuel discharged from the fuel pump to the internal combustion engine;
A branch passage branched from a branch point provided in the middle of the fuel supply passage, and returning a surplus portion of the fuel discharged from the fuel pump to the fuel holding chamber;
The surplus fuel introduced into the branch passage is injected from the injection nozzle toward the throat portion, and the negative pressure generated by the injection is used to suck the fuel outside the fuel holding chamber. A fuel supply device comprising: a jet pump that discharges into the fuel holding chamber together with the fuel injected from the injection nozzle;
Flow rate varying means for varying the discharge flow rate of the fuel pump;
The fuel of the fuel discharged from the fuel pump to the fuel supply passage disposed on the fuel supply passage on the downstream side of the fuel pump or on the downstream side of the discharge port and upstream of the branch point A check valve to prevent return to the pump;
A throttle means that is constituted by an injection nozzle of the jet pump and adjusts the pressure of the fuel in the fuel supply passage by controlling the discharge flow rate of the fuel pump;
It is arranged on the passage before the injection nozzle of the jet pump, and opens when the pressure of the fuel introduced from the fuel supply passage to the branch passage exceeds a predetermined value, and distributes the fuel to the injection nozzle. A residual pressure holding valve that holds the pressure of the fuel in the fuel supply passage and the branch passage by permitting and closing the valve when it is equal to or less than the predetermined value to prevent the fuel from flowing to the injection nozzle; A fuel supply device comprising: A fuel pump for delivering fuel to the internal combustion engine;
A fuel holding chamber for holding fuel for suction by the fuel pump;
A fuel supply passage for sending the fuel discharged from the fuel pump to the internal combustion engine;
A branch passage branched from a branch point provided in the middle of the fuel supply passage, and returning a surplus portion of the fuel discharged from the fuel pump to the fuel holding chamber;
The surplus fuel introduced into the branch passage is injected from the injection nozzle toward the throat portion, and the negative pressure generated by the injection is used to suck the fuel outside the fuel holding chamber. A fuel supply device comprising: a jet pump that discharges into the fuel holding chamber together with the fuel injected from the injection nozzle;
Flow rate varying means for varying the discharge flow rate of the fuel pump;
The fuel of the fuel discharged from the fuel pump to the fuel supply passage disposed on the fuel supply passage on the downstream side of the fuel pump or on the downstream side of the discharge port and upstream of the branch point A check valve to prevent return to the pump;
A throttle means that is constituted by an injection nozzle of the jet pump and adjusts the pressure of the fuel in the fuel supply passage by controlling the discharge flow rate of the fuel pump;
It is arranged on the passage before the injection nozzle of the jet pump, and opens when the pressure of the fuel introduced from the fuel supply passage to the branch passage exceeds a predetermined value, and distributes the fuel to the injection nozzle. A residual pressure holding valve that holds the pressure of the fuel in the fuel supply passage and the branch passage by permitting and closing the valve when it is equal to or less than the predetermined value to prevent the fuel from flowing to the injection nozzle; ,
A fuel supply apparatus comprising: one or a plurality of auxiliary throttle means disposed on a passage in front of the injection nozzle and configured to drop the pressure of fuel gradually flowing toward the injection nozzle. A fuel pump for delivering fuel to the internal combustion engine;
A fuel holding chamber for holding fuel for suction by the fuel pump;
A fuel supply passage for sending the fuel discharged from the fuel pump to the internal combustion engine;
A branch passage branched from a branch point provided in the middle of the fuel supply passage, and returning a surplus portion of the fuel discharged from the fuel pump to the fuel holding chamber;
The surplus fuel introduced into the branch passage and injected into the branch passage is injected from the injection nozzle toward the throat portion, and the fuel outside the fuel holding chamber is sucked using the negative pressure generated by the injection. A jet pump for discharging into the fuel holding chamber together with the fuel injected from the injection nozzle,
Flow rate varying means for varying the discharge flow rate of the fuel pump;
The fuel of the fuel discharged from the fuel pump to the fuel supply passage, disposed on the fuel supply passage on the downstream side of the discharge port of the fuel pump or upstream of the branch point. A check valve to prevent return to the pump;
A throttle means configured by an injection nozzle of the jet pump, and adjusting the pressure of the fuel in the fuel supply passage by controlling the discharge flow rate of the fuel pump;
It is disposed on a passage in front of the jet nozzle of the jet pump, and opens when the pressure of the fuel introduced from the fuel supply passage to the branch passage exceeds a predetermined value to allow the fuel to flow to the injection nozzle. A residual pressure holding valve that holds the pressure of the fuel in the fuel supply passage and the branch passage by permitting and closing the valve when it is equal to or less than the predetermined value to prevent the fuel from flowing to the injection nozzle; , And
The fuel supply device, wherein the residual pressure holding valve is incorporated in a body of the jet pump that constitutes a passage in front of the injection nozzle.

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