JP2011220306A - Fuel supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel supply device which can regulate the pressure of fuel supplied to a fuel injection valve without making a structure complex and can prevent a manufacturing cost increase.SOLUTION: The fuel supply device 1 has a branch passage 32 to make the fuel, supplied from a fuel pump 11 to a fuel supply passage 31, join fuel which is exhausted from an exhaust hole 28a and a fuel exhaust port 21b of a hollow member 28 at a confluence portion 34. The branch passage 32 has a converging section 35.

Description

  The present invention relates to a fuel supply device, and more particularly to a fuel supply device including a pressure regulator capable of adjusting a pressure of the fuel supplied from a fuel pump to a fuel injection valve of an internal combustion engine.

  Conventionally, in a fuel supply device that supplies fuel stored in a fuel tank body to a fuel injection valve by a fuel pump, a part of the fuel discharged from the fuel pump is put into the fuel tank body through a pressure regulator. By returning, the fuel pressure in the fuel supply passage between the fuel pump and the fuel injection valve, that is, the fuel pressure supplied to the fuel injection valve (hereinafter referred to as fuel pressure) is adjusted to a predetermined pressure.

  Then, by controlling the fuel pressure supplied to the fuel injection valve according to the operating state of the internal combustion engine, fuel is supplied from the fuel injection valve to the internal combustion engine with an optimal fuel supply amount according to the operating state of the internal combustion engine. I have to.

  Conventionally, as a fuel supply device capable of adjusting the fuel pressure, for example, a device as described in Patent Document 1 is known. The device described in Patent Document 1 includes a high-pressure side pressure regulator, a low-pressure side pressure regulator, and a control valve for a low-pressure side return passage.

  When adjusting the fuel pressure supplied to the fuel injection valve to a high fuel pressure based on the operating state of the internal combustion engine, the control valve for the low pressure side return passage is controlled to operate the high pressure side pressure regulator, and the internal combustion engine is operated. When the fuel pressure supplied to the fuel injection valve is adjusted to a low fuel pressure based on the operating state of the engine, the low pressure side recirculation passage control valve is controlled to operate and the low pressure side pressure regulator is operated. The fuel pressure supplied to the injection valve can be adjusted.

  Further, this fuel injection device adjusts the fuel pressure supplied to the fuel injection valve by the high pressure side pressure regulator and the low pressure side pressure regulator in two stages, so that the load applied to the fuel pump in the operation state adjusted to the low fuel pressure The power consumption of the fuel pump can be reduced.

JP 2008-112454 A

  However, in such a conventional fuel supply device, the fuel pressure supplied from the fuel pump to the fuel injection valve is adjusted in two stages by the high-pressure side pressure regulator and the low-pressure side pressure regulator. There is a problem that the number of parts for adjustment increases and the configuration of the fuel supply apparatus becomes complicated, and the manufacturing cost of the fuel supply apparatus increases.

  The present invention has been made to solve the above-described conventional problems, and can prevent the configuration from becoming complicated and adjust the fuel pressure supplied to the fuel injection valve, thereby increasing the manufacturing cost. It is an object of the present invention to provide a fuel supply device that can prevent this.

  In order to achieve the above object, a fuel supply apparatus according to the present invention includes (1) a pressure regulator capable of introducing fuel supplied from a fuel pump to a fuel injection valve of an internal combustion engine and adjusting the pressure of the fuel, The pressure regulator includes a housing in which a fuel introduction passage for introducing fuel and a fuel discharge passage for discharging fuel are formed, and the fuel introduction passage and the fuel discharge according to the fuel pressure in the fuel introduction passage inside the housing. A fuel supply comprising a partition-shaped pressure regulating member that communicates with and shuts off the passage, and biasing means that biases the pressure regulating member in a direction that shuts off the fuel introduction passage and the fuel discharge passage. A fuel supply passage for supplying fuel discharged from the fuel pump to the fuel injection valve; a branch from the fuel supply passage; From a branch passage for introducing the fuel supplied to the fuel supply passage into the fuel introduction passage of the pressure regulator, and a joining portion for joining the fuel discharged from the fuel pump and the fuel discharged from the fuel discharge passage The fuel merging passage includes a throttle portion.

  In this fuel supply device, since the pressure regulating member of the pressure regulator is constantly urged by the urging means to close the valve, the operating pressure of the fuel acting on the pressure regulating member through the fuel supply passage is urged by the urging means. When it becomes larger than the power, the pressure regulating member opens and is discharged from the fuel discharge passage, and the fuel pressure of the fuel injection valve is adjusted to the low pressure side.

  Further, the fuel supply device has a fuel merging passage for joining the fuel supplied from the fuel pump to the fuel supply passage with the fuel discharged from the fuel discharge passage at the merging portion, and the fuel merging passage has a throttle portion. When fuel is supplied from the fuel pump to the fuel merging passage, the flow velocity increases when the fuel passes through the throttling portion, and the merging portion located on the downstream side of the throttling portion becomes negative pressure due to the venturi action.

  When the merge part becomes negative pressure, the pressure regulating member of the pressure regulator that opens and closes the fuel discharge passage is sucked in the valve closing direction by the negative pressure, so that when the operating pressure of the fuel acts on the pressure regulating member, the pressure regulating member It becomes difficult to open the valve. For this reason, the fuel pressure of the fuel injection valve is adjusted to the high pressure side.

  In this way, by generating a negative pressure at the joining portion by the fuel joining passage, the configuration of the fuel supply device can be prevented from being complicated, and the fuel pressure supplied to the fuel injection valve can be adjusted. An increase in the manufacturing cost of the apparatus can be prevented.

  In addition, when fuel is not supplied to the fuel merge passage, the fuel pressure of the fuel injection valve can be adjusted to the low pressure side without generating a negative pressure at the merge portion, thereby reducing the load on the fuel pump. And the power consumption of the fuel pump can be reduced.

In the fuel supply device described in (1) above, (2) the fuel supply device includes a flow rate control valve that is provided on the branch passage and variably controls the amount of fuel flowing through the fuel junction passage.
Since this fuel supply device has a flow control valve that variably controls the amount of fuel flowing through the fuel merging passage on the fuel merging passage, by varying the amount of fuel flowing through the fuel merging passage, the throttle portion of the fuel merging passage can be reduced. The flow rate of the flowing fuel can be controlled. For this reason, it is possible to adjust the valve opening pressure of the pressure adjusting member by adjusting the magnitude of the negative pressure generated in the junction, and to adjust the fuel pressure of the fuel injection valve on the low pressure side.

  For this reason, for example, in an operation region where the fuel consumption of the internal combustion engine is low, such as when the operation state of the internal combustion engine is idle operation, or during steady operation where fluctuations in the rotational speed or load of the internal combustion engine are small, flow control is performed. By adjusting the opening of the valve, the fuel pressure of the fuel injection valve can be controlled to an arbitrary low pressure, the load on the fuel pump can be reduced, and the power consumption of the fuel pump can be reduced.

  Also, in an operating region where the fuel consumption of the internal combustion engine is large, such as during acceleration when the rotational speed or load of the internal combustion engine is large, the fuel pressure of the fuel injection valve is increased by increasing the opening of the flow control valve. Can be controlled.

  (3) In the fuel supply device according to (1) or (2), (3) the fuel merge passage is branched from the fuel supply passage, and the fuel discharged from the fuel pump joins the fuel via the fuel supply passage. It consists of what is supplied to the passage.

  In this fuel supply device, the fuel merge passage supplies the fuel discharged from the fuel pump to the merge portion via the fuel supply passage, so that the fuel discharged from the fuel discharge passage and the fuel discharged from the fuel pump merge. It can be merged at the part.

  (4) In the fuel supply device described in (1) or (2) above, (4) the fuel pump discharges fuel into the fuel supply passage and first discharge port that discharges fuel into the fuel supply passage; 2, and the fuel merging passage is configured to supply the fuel discharged from the second discharge port to the merging portion.

  Since this fuel supply device supplies the fuel discharged from the second discharge port of the fuel pump to the merging portion, the fuel discharged from the fuel discharge passage and the fuel discharged from the fuel pump are merged at the merging portion. be able to.

  In the fuel supply device according to the above (1) to (4), (5) the fuel supply device is housed in a fuel tank body that stores fuel, and has a sub-cup that houses the fuel pump and the pressure regulator therein. The sub cup includes a communication hole that communicates the fuel tank main body and the merging portion.

  In this fuel supply device, since the sub-cup has a communication hole that communicates the fuel tank main body and the merging portion, the sub-cup and the fuel are utilized by utilizing the negative pressure generated in the merging portion when the fuel passes through the throttle portion. Fuel can be sucked into the sub cup from the fuel tank main body through the communication hole communicating with the tank main body.

  For this reason, the liquid level of the fuel in the sub-cup provided in the fuel tank body can be raised, and the fuel in the fuel tank body is biased due to centrifugal action or the like due to turning or traveling on the vehicle Even so, the fuel stored in the sub-cup can be reliably sucked by the fuel pump.

  In addition, when the fuel in the sub-cup does not exist around the merging portion due to the centrifugal action or the like due to the vehicle turning or running on a slope, there is no means to actively supply fuel to the merging portion, An air layer is formed at the junction.

  In particular, on the low pressure side where the amount of fuel flowing through the merging portion is small, when the merging portion becomes negative pressure, an air layer is easily formed at the merging portion, so that the fuel in the sub-cup passes into the fuel tank body through the communication hole. There is a risk of backflow.

  In the present invention, since the fuel tank main body has a communication hole for communicating with the merging portion and the fuel discharged from the fuel discharge passage is merged into the merging portion, the amount of fuel supplied to the merging portion is small When the merge part becomes negative pressure, the merge part can be made liquid-tight by the fuel discharged from the fuel discharge passage to the merge part, and an air layer can be prevented from being formed in the merge part. it can.

  For this reason, it is possible to prevent the fuel in the sub-cup from flowing back to the fuel tank body by utilizing the viscosity of the fuel in the merging portion, and reliably suck the fuel into the sub-cup from the fuel tank body through the communication hole. And the liquid level of the fuel in the sub cup can be raised. As a result, fuel can be stably supplied from the fuel pump to the fuel injection valve.

  According to the present invention, it is possible to provide a fuel supply device that can prevent the configuration from becoming complicated, adjust the fuel pressure supplied to the fuel injection valve, and prevent the manufacturing cost from increasing. Can do.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the fuel supply apparatus which concerns on this invention, and is a schematic block diagram of a fuel tank main body and a fuel supply apparatus. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the fuel supply apparatus which concerns on this invention, and is a schematic block diagram of a fuel supply apparatus. It is a figure which shows 1st Embodiment of the fuel supply apparatus which concerns on this invention, and is sectional drawing in the valve closing state of a pressure regulator. It is a figure which shows 1st Embodiment of the fuel supply apparatus which concerns on this invention, and is sectional drawing in the valve opening state of a pressure regulator. It is a figure which shows 2nd Embodiment of the fuel supply apparatus which concerns on this invention, and is a schematic block diagram of a fuel supply apparatus.

(First embodiment)
Hereinafter, embodiments of a fuel supply apparatus according to the present invention will be described with reference to the drawings.
1 to 4 are views showing a first embodiment of a fuel supply apparatus according to the present invention.
First, the configuration will be described.

  1 and 2, a fuel supply device 1 includes a fuel tank main body 3 that stores fuel consumed by an engine 2 as an internal combustion engine, for example, gasoline, a sub cup 4 accommodated in the fuel tank main body 3, A fuel pumping circuit 10 that pumps and supplies fuel stored in the cup 4 and stored in the sub-cup 4 to a plurality of injectors 5 of the engine 2, and a fuel pressure supplied from the fuel pumping circuit 10 to the injector 5 are adjusted. And a pressure regulator 20.

  The pressure regulator 20 is accommodated in the sub cup 4 together with the fuel pump 11. The injector 5 constitutes the fuel injection valve of the present invention, and only one injector 5 is shown in FIGS.

  The engine 2 is a multi-cylinder internal combustion engine mounted on an automobile, for example, a four-cycle gasoline engine. An injector 5 provided corresponding to a plurality of cylinders of the engine 2 is, for example, an end portion 5a on the injection hole side. Are exposed in intake ports (not shown) of a plurality of cylinders.

  Further, the fuel from the fuel pumping circuit 10 is distributed to each injector 5 via the delivery pipe 6.

  The sub-cup 4 is supported by the other end of a support member 7 having one end attached to the ceiling of the fuel tank body 3, and the support member 7 defines a certain distance from the bottom surface of the fuel tank body 3. In this manner, the fuel tank body 3 is attached.

  The support members 7 are provided at regular intervals in the circumferential direction of the sub cup 4, and the fuel in the fuel tank main body 3 enters the sub cup 4 from between the support members 7 through the upper end of the sub cup 4. In addition to being introduced, it is sucked into the sub-cup 4 from below the sub-cup 4 through a merging portion described later.

  The fuel pumping circuit 10 pumps up the fuel in the fuel tank main body 3 and pressurizes and discharges the fuel, a suction filter 12 that blocks foreign matter on the suction port side of the fuel pump 11, and a discharge of the fuel pump 11. A fuel filter 13 that removes foreign matters in the discharged fuel on the outlet side and a check valve 14 that is located upstream of the fuel filter 13 are configured.

  The fuel pump 11 has, for example, a pump operating part having an impeller for pump operation and a built-in DC motor that drives the pump operating part. The fuel pump 11 pumps up fuel from the fuel tank body 3 and discharges it by pressurizing. In addition, the discharge amount per unit time can be variably controlled by changing the rotation speed [rpm] of the built-in motor.

  The check valve 14 opens in the direction in which fuel is supplied from the fuel pump 11 to the injector 5 side, and closes and pressurizes in the direction in which fuel flows back from the injector 5 side to the fuel pump 11 side. It is designed to prevent back flow of the supplied fuel.

  Further, the fuel pump 11 is driven and stopped by controlling whether or not the internal motor is energized by an electronic control unit (hereinafter referred to as ECU) 8 described later, and also changes the fuel discharge amount per unit time. The energization of the built-in motor is controlled so that The fuel pump 11 may be constituted by a pump that takes only two states, a driving state and a non-driving state in which fuel is discharged at a constant discharge amount.

The pressure regulator 20 includes a housing 21 having a fuel inlet 21a into which a part of the fuel discharged from the fuel pump 11 is introduced and a fuel outlet 21b through which the fuel is discharged. The pair of concave housing members 18 and 19 are formed by caulking and coupling with their outer peripheral flange portions 18j and 19j.
In addition, the housing members 18 and 19 are formed by pressing a steel plate or a stainless steel plate into a concave shape, but may be formed from a molten material into the illustrated shape.

  Inside the housing 21 is provided a partition-like pressure regulating member 22 that divides the inside of the housing 21 into two chambers. The pressure regulating member 22 includes a partition wall portion 24 that defines a pressure regulating chamber 23 that communicates with the fuel introduction port 21 a between the pressure regulating member 22 and the pressure regulating chamber 23 at an opening degree corresponding to the fuel pressure in the pressure regulating chamber 23. Is integrated with a movable valve body portion 25 that is displaced in the valve opening direction so as to communicate with the fuel discharge port 21b, and the partition wall portion 24 always receives the working pressure (fuel pressure) in the pressure regulating chamber 23 on one side thereof. It is supposed to be.

  The partition wall portion 24 of the pressure regulating member 22 also forms a back pressure chamber 26 for applying a back pressure to the pressure regulating chamber 23 between the housing 21 and the other surface side. A compression coil spring 27 is provided to urge the movable valve body 25 of the pressure regulating member 22 in the valve closing direction.

  In addition, at least one atmospheric pressure introduction hole 19 a is formed in the housing member 19 that forms the back pressure chamber 26 together with the pressure regulating member 22. Here, the compression coil spring 27 constitutes an urging means.

  More specifically, the partition wall portion 24 of the pressure adjusting member 22 includes, for example, a base material layer (for example, polyamide synthetic fiber) and a rubber layer (for example, hydrogenated nitrile rubber, fluorine rubber, or the like) that hardly deteriorates against fuel. The movable valve body portion 25 of the pressure regulating member 22 is, for example, a metal (for example, tool steel, stainless steel, etc.) supported by the central portion of the partition wall portion 24. ) Made of disc-shaped valve body plate. The movable valve body 25 and the partition wall 24 are fixed by, for example, vulcanization adhesion of the rubber layer.

  As shown in FIG. 2, a hollow member 28 is arranged inside the housing 21 so as to face the movable valve body 25 of the pressure regulating member 22 inside the pressure regulating chamber 23. The hollow member 28 has a discharge hole 28 a communicating with the fuel discharge port 21 b, and the discharge hole 28 a has an opening according to the displacement of the movable valve body 25 on the inner end side that opens inside the pressure regulating chamber 23. Is to change.

  Further, the movable valve body portion 25 of the pressure regulating member 22 has a flat surface 25 a facing the hollow member 28, and the hollow member 28 is in the same direction with respect to the movable valve body portion 25 of the pressure regulating member 22 ( The valve seat surface 28b is located on the same plane as the flat surface 25a.

  Therefore, when the movable valve body portion 25 closes the hollow member 28 by the compression coil spring 27, the valve seat surface 28b of the hollow member 28 and the flat surface 25a of the movable valve body portion 25 are in close contact with each other, and the pressure regulating chamber 23 Thus, the fuel can be prevented from being discharged into the discharge hole 28a.

  The hollow member 28 is composed of a cylindrical member, and the hollow member 28 is fixed to a housing member 18 formed in a plurality of stepped concave shapes so as to become deeper inward in the radial direction. The housing member 18 of the housing 21 is positioned radially inward with respect to the first annular wall portion 18a and the first annular wall portion 18a that are spaced radially outward with respect to the hollow member 28. A second annular wall portion 18b in which a fuel introduction port 21a is formed, and a third annular wall portion 18c that is located radially inward with respect to the second annular wall portion 18b and supports the hollow member 28; have.

  Thus, in this embodiment, fuel is introduced into the pressure regulating chamber 23 through the fuel introduction port 21a formed in the second annular wall portion 18b of the housing member 18, and the fuel introduction port 21a and the fuel introduction port 21a The pressure regulating chamber 23 constitutes a fuel introduction passage.

  Further, the pressure regulating member 22 discharges the pressure regulating chamber 23 and the hollow member 28 when the movable valve body 25 abuts and separates from the hollow member 28 according to the fuel pressure introduced into the pressure regulating chamber 23. The hole 28a is communicated and blocked. The compression coil spring 27 urges the movable valve body 25 of the pressure regulating member 22 so that the movable valve body 25 is brought into contact with the valve seat surface 28 b of the hollow member 28.

  For this reason, the movable valve body 25 of the pressure regulating member 22 moves upward from the valve seat surface 28 b of the hollow member 28 against the urging force of the compression coil spring 27 in response to the operating pressure introduced into the pressure regulating chamber 23. When the discharge hole 28a is released, the fuel is discharged through the discharge hole 28a and the fuel discharge port 21b. In the present embodiment, the discharge hole 28a and the fuel discharge port 21b constitute a fuel discharge passage.

  On the other hand, the fuel inlet 21 a of the pressure regulator 20 is connected via a branch passage 32 to a fuel supply passage 31 that is a circuit portion downstream of the check valve 14 of the fuel pumping circuit 10.

  Here, the branch passage 32 of the fuel supply passage 31 includes, for example, a branch portion 32 a formed by a part 17 of the filter case that houses the filter elements (not shown) of the suction filter 12 and the fuel filter 13 together with the fuel pump 11. Have.

  Therefore, a part of the fuel discharged from the fuel pump 11 is branched from the fuel supply passage 31 to the branch passage 32 and then introduced from the branch passage 32 into the pressure regulating chamber 23 through the fuel introduction port 21a.

  The fuel discharge port 21 b is connected to a fuel supply passage 31 that is a circuit portion downstream of the check valve 14 of the fuel pumping circuit 10 via a branch passage 33.

  That is, the branch passage 33 is branched from the fuel supply passage 31 and extends to the fuel discharge port 21b, and a joining portion that joins the fuel branched from the fuel supply passage 31 and the fuel discharged from the fuel discharge port 21b. 34. In the present embodiment, the branch passage 33 constitutes a fuel merge passage.

  The branch passage 33 has a branch portion 33 a formed by a part 17 of the filter case, and a throttle portion 35 is formed in the downstream portion of the branch passage 33. The throttle portion 35 is formed in a tapered shape from the inner peripheral surface of the branch portion 33 a toward the downstream side of the branch portion 33 a, and the junction passage 34 is formed in the branch passage 33 downstream of the throttle portion 35. . That is, the branch passage 33 is formed with a throttle portion 35 on the upstream side of the merging portion 34.

  Further, a flow control valve 37 is provided in the branch passage 33, and the flow control valve 37 changes the opening degree of the branch passage 33 based on a command signal from the ECU 8, thereby fuel flowing through the branch passage 33. The amount is variable.

  In addition to a backup memory composed of a nonvolatile memory such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an EEPROM (Electrically Erasable and Programmable Read Only Memory, registered trademark), the ECU 8 The ECU 8 includes an input interface circuit, an output interface circuit, and the like. The ECU 8 receives an ON / OFF signal of an ignition switch of the vehicle and is supplied with power from a battery.

  Various sensor groups such as an air-fuel ratio sensor 41 that detects the air-fuel ratio of the exhaust gas and an engine speed sensor 42 that detects the rotational speed of the engine 2 are connected to the input interface circuit of the ECU 8. Sensor information is taken into the ECU 8 through an input interface circuit including an A / D converter and the like.

  The output interface circuit of the ECU 8 is connected to the injector 5, the fuel pump 11, the flow rate control valve 37, or a switching element for variably controlling the current of the fuel pump 11.

  The ECU 8 determines the driving state of the vehicle based on the air-fuel ratio sensor 41, the engine speed sensor 42, etc., and variably controls the flow control valve 37 according to the vehicle handling state, so that the ECU 8 is supplied to the branch passage 32. The amount of fuel to be controlled is controlled.

  On the other hand, a communication hole 4a is formed in the sub-cup 4, and the communication hole 4a communicates the fuel tank body 3 and the junction 34 through a communication hole 33b formed in the branch portion 33a.

  In the present embodiment, when fuel is supplied from the fuel supply passage 31 to the branch passage 33, the flow rate of the fuel increases when passing through the throttle portion 35, so that the merging portion 34 downstream of the throttle portion 35. Becomes negative pressure by venturi action.

  When the upper end of the sub cup 4 becomes higher than the liquid level of the fuel stored in the fuel tank main body 3, that is, when the fuel is not replenished from the upper end of the sub cup 4 to the fuel tank main body 3, By the generated negative pressure, the fuel in the fuel tank main body 3 is sucked into the sub cup 4 through the communication hole 4a, so that the liquid level of the fuel in the sub cup 4 rises.

  Further, the movable valve body portion 25 of the pressure regulating member 22 is sucked in the valve closing direction through the discharge hole 28a of the hollow member 28 by the negative pressure generated in the merging portion 34, so that the operation pressure acts on the pressure regulating member 22. However, the movable valve body 25 of the pressure regulating member 22 is difficult to move in the valve opening direction, and the fuel pressure downstream of the check valve 14 is maintained at a high pressure. Thus, the merge part 34 of the branch passage 33 of the present embodiment functions as a jet pump.

Next, the operation will be described.
In the fuel supply device 1 of the present embodiment configured as described above, the fuel pump 11 is controlled to be driven by the ECU 8 while the engine 2 is in operation. Therefore, fuel is supplied from the fuel pump 11 to the injector 5 through the fuel supply passage 31.

  The fuel supplied from the fuel supply passage 31 to the branch passage 32 is introduced into the pressure regulating chamber 23 from the fuel introduction port 21a. The fuel introduced into the pressure regulating chamber 23 acts on the partition wall 24 and the movable valve body 25 of the pressure regulating member 22 as the operating pressure P (see FIG. 3).

  The flow control valve 37 varies the amount of fuel flowing through the branch passage 33 by varying the opening of the branch passage 33, and the ECU 8 varies the flow control valve 37 according to the operating state of the engine 2. Thus, the set pressure of the pressure regulator 20 can be varied.

  Specifically, the ECU 8 determines the fuel consumption amount of the engine 2 based on the detection information from the air-fuel ratio sensor 41 and the engine speed sensor 42, such as at the time of acceleration when the speed of the engine 2 and the load change are large. When it is determined that the operation region is large, the amount of fuel flowing through the branch passage 33 is increased by controlling the flow control valve 37 to a large opening.

  The fuel supplied to the branch passage 33 increases in flow velocity by passing through the throttle portion 35 as indicated by the symbol a in FIG. 3, so that the merging portion 34 downstream of the throttle portion 35 becomes negative pressure by the venturi action. . The movable valve body 25 of the pressure regulating member 22 is sucked in the valve closing direction through the discharge hole 28a of the hollow member 28 by the negative pressure generated in the merging portion 34.

  When the flow control valve 37 is controlled to have a large opening, the amount of fuel passing through the throttle portion 35 increases, so that the negative pressure generated in the merging portion 34 increases and the movable valve body portion 25 of the pressure regulating member 22 is closed. The suction force for suctioning in the valve direction increases. For this reason, the valve opening pressure of the movable valve body part 25 becomes large, and the movable valve body part 25 becomes difficult to open.

  For this reason, the fuel in the pressure regulating chamber 23 and the fuel pressure between the check valve 14 and the injector 5 are set on the high pressure side. At this time, the fuel in the fuel tank body 3 is sucked into the sub cup 4 through the communication hole 4a as shown by the arrow b in FIG. When the pressure regulator 20 is set to the high pressure side, the negative pressure generated at the junction 34 increases, so the amount of fuel per unit time of fuel sucked into the fuel tank body 3 through the communication holes 4a and 33b is reduced. Become more.

  Therefore, when the fuel in the sub-cup 4 is largely consumed by the engine 2, the liquid level of the fuel in the sub-cup 4 can be raised.

  On the other hand, the ECU 8 is based on detection information from the air-fuel ratio sensor 41 and the engine speed sensor 42, when the engine 2 is in an idling operation, or when the engine 2 is in a steady operation with small fluctuations in the speed or load. When it is determined that the engine 2 is in an operating region where the fuel consumption is small, the flow control valve 37 is controlled to a small opening so that the amount of fuel flowing through the branch passage 33 is reduced.

  At this time, as indicated by an arrow a in FIG. 4, the amount of fuel passing through the throttle portion 35 is reduced, so that the negative pressure generated in the merging portion 34 is reduced and the movable valve body portion 25 of the pressure regulating member 22 is closed. The suction force for suctioning in the valve direction is reduced. For this reason, the valve opening pressure of the movable valve body portion 25 is reduced, and the movable valve body portion 25 is opened by the operating pressure P of the fuel. For this reason, the fuel (indicated by arrow c in FIG. 4) is discharged from the pressure regulating chamber 23 through the discharge hole 28a of the hollow member 28.

  For this reason, the fuel in the pressure regulation chamber 23 and the fuel pressure between the check valve 14 and the injector 5 are set to the low pressure side. At this time, the fuel in the fuel tank main body 3 is sucked into the sub cup 4 through the communication hole 4 a by the negative pressure generated in the junction 34.

  When the fuel pressure is set to the low pressure side, the amount of fuel flowing through the branch passage 33 is controlled by variably controlling the opening degree of the flow control valve 37 based on detection information from the air-fuel ratio sensor 41 and the engine speed sensor 42. Can be made variable, so that an arbitrary fuel pressure can be set on the low pressure side.

  That is, on the low pressure side, the suction force of the movable valve body portion 25 due to the negative pressure becomes the valve opening pressure of the movable valve body portion 25, so that the suction force of the movable valve body portion 25 is variable according to the operating state of the engine 2. Thus, an arbitrary fuel pressure can be set on the low pressure side.

  Further, when the pressure regulator 20 is set to the low pressure side where the fuel consumption of the engine 2 is small, the negative pressure generated in the merging portion 34 causes the fuel tank body 3 to enter the sub cup 4 through the communication hole 4a. The amount of fuel sucked increases in proportion to the magnitude of the negative pressure in the merge portion 34.

  For this reason, on the low pressure side, the amount of fuel in the sub-cup 4 supplied from the fuel pump 11 to the injector 5 per unit time is small, so the amount of decrease in the fuel in the sub-cup 4 per unit time is also small.

  In this case, since a small amount of fuel is sucked into the sub cup 4 from the fuel tank body 3 through the communication hole 4a, the sub cup 4 is replenished with fuel corresponding to the amount of fuel decrease in the sub cup 4. Can do.

Further, when the pressure regulator 20 is set on the high pressure side where the fuel consumption of the engine 2 is large, the amount of fuel in the sub cup 4 supplied from the fuel pump 11 to the injector 5 increases per unit time. As described above, the amount of fuel in the sub-cup 4 that decreases per unit time increases. However, as described above, more fuel is sucked into the sub-cup 4 from the fuel tank body 3 through the communication hole 4a. The sub-cup 4 can be replenished with fuel corresponding to the amount of fuel decrease.
As a result, the liquid level of the sub cup 4 always rises, and the fuel can be stably supplied from the fuel pump 11 to the injector 5.

  Thus, in this embodiment, the branch passage 32 that joins the fuel supplied from the fuel pump 11 to the fuel supply passage 31 to the fuel discharged from the discharge hole 28a and the fuel discharge port 21b of the hollow member 28 at the junction 34. And a flow control valve 37 that variably controls the amount of fuel flowing through the branch passage 33 on the branch passage 33. When the fuel supplied from the fuel supply passage 31 to the branch passage 32 passes through the throttle portion 35, the flow velocity of the fuel is increased, so that the merging portion 34 can be made negative pressure by the venturi action. Further, by varying the amount of fuel flowing through the branch passage 33 by the flow rate control valve 37, the magnitude of the negative pressure generated at the junction 34 can be adjusted.

  For this reason, the movable valve body 25 of the pressure regulating member 22 that opens and closes the discharge hole 28 a of the hollow member 28 can be sucked in the valve closing direction by the negative pressure acting on the discharge hole 28 a of the hollow member 28. Then, by adjusting the magnitude of this negative pressure and adjusting the valve opening pressure of the movable valve body 25, the fuel pressure downstream of the check valve 14 can be set to a predetermined low pressure or high pressure. it can.

  Thus, by providing the throttle part 35 in the branch passage 33 and generating a negative pressure in the merging part 34, it is possible to prevent the configuration of the fuel supply device 1 from being complicated and to be downstream of the check valve 14. A fuel pressure can be adjusted and it can prevent that the manufacturing cost of the fuel supply apparatus 1 increases.

  Further, the fuel pressure downstream of the check valve 14 can be reduced by adjusting the amount of fuel flowing through the branch passage 33 by the flow control valve 37 and reducing the negative pressure generated in the junction 34. The load applied to the fuel pump 11 can be reduced, and the power consumption of the fuel pump 11 can be reduced.

  The fuel supply device 1 of the present embodiment is housed in a fuel tank body 3 that stores fuel, and has a sub cup 4 that houses a fuel pump 11 and a pressure regulator 20 inside. Since the communication hole 4a that connects the fuel tank main body 3 and the merging portion 34 is formed, the fuel can be sucked into the sub cup from the fuel tank main body 3 through the communication hole 4a using the negative pressure generated in the merging portion 34. .

  For this reason, the liquid level of the fuel in the sub-cup 4 located in the fuel tank main body 3 can be raised, and the fuel in the fuel tank main body 3 is subjected to centrifugal action or the like due to turning or running on the slope of the vehicle. Even if it is biased, the fuel stored in the sub-cup 4 can be reliably sucked by the fuel pump 11.

  On the low pressure side where the amount of fuel flowing through the merging portion 34 is small when the fuel in the sub-cup 4 no longer exists in the vicinity of the merging portion 34 due to centrifugal action or the like due to turning or running on a slope of the vehicle. When the merging portion 34 has a negative pressure, an air layer is easily formed in the merging portion 34, so that the fuel in the sub cup 4 may flow back to the fuel tank body 3 through the communication holes 4a and 33b. .

  In the present embodiment, since the communication holes 4a and 33b are provided to communicate the fuel tank body 3 and the merging portion 34, the fuel discharged from the discharge holes 28a of the hollow member 28 is merged into the merging portion 34. When the joining portion becomes negative pressure with a small amount of fuel supplied to the joining portion 34, the joining portion 34 is made liquid-tight by the fuel discharged from the discharge hole 28a of the hollow member 28 to the joining portion 34. It is possible to prevent an air layer from being formed at the junction 34.

  Therefore, it is possible to prevent the fuel in the sub-cup 4 from flowing back to the fuel tank body 3 by using the viscosity of the fuel in the junction 34, and the fuel from the fuel tank body 3 through the communication holes 4a and 33b. Can be reliably sucked into the sub-cup 4, and the fuel level in the sub-cup 4 can be raised. As a result, fuel can be stably supplied from the fuel pump 11 to the injector 5.

(Second Embodiment)
FIG. 5 is a diagram showing a second embodiment of the fuel supply apparatus according to the present invention. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.
In FIG. 5, the fuel pumping circuit 10 includes a fuel pump 51 instead of the fuel pump 11, and the fuel pump 51 has a first discharge port 51a and a second discharge port 51b for discharging fuel. ing.

  The first discharge port 51 a discharges fuel into the fuel supply passage 31, and the second discharge port 51 b discharges fuel into the fuel merge passage 53. Further, a fuel filter 52 is provided on the downstream side of the second discharge port 51b, and this fuel filter 52 removes foreign matters in the fuel discharged from the second discharge port 51b to the fuel junction passage 53. It is like that.

  The fuel merging passage 53 has a merging portion 34 for merging the fuel discharged from the second discharge port 51b of the fuel pump 51 and the fuel discharged from the fuel discharge port 21b, and is throttled to the upstream side of the merging portion 34. A portion 35 is formed. In the present embodiment, the fuel merge passage 53 is provided independently of the fuel supply passage 31.

  As described above, in the present embodiment, the fuel supplied from the second discharge port 51b of the fuel pump 51 to the fuel merge passage 53 is discharged from the discharge hole 28a and the fuel discharge port 21b of the hollow member 28 at the merge portion 34. The throttle part 35 is provided on the fuel merging passage 53 on the upstream side of the merging part 34 and the amount of fuel flowing through the fuel merging passage 53 is variably controlled on the fuel merging passage 53. A valve 37 was provided.

  For this reason, when the fuel supplied to the fuel merging passage 53 passes through the throttle portion 35, the flow velocity of the fuel is increased, so that the merging portion 34 can be made negative pressure by the venturi action. Further, by varying the amount of fuel flowing through the fuel merge passage 53 by the flow rate control valve 37, the magnitude of the negative pressure generated in the merge section 34 can be adjusted.

  For this reason, the movable valve body 25 of the pressure regulating member 22 that opens and closes the discharge hole 28 a of the hollow member 28 can be sucked in the valve closing direction by the negative pressure acting on the discharge hole 28 a of the hollow member 28. Then, by adjusting the magnitude of this negative pressure and adjusting the valve opening pressure of the movable valve body 25, the fuel pressure downstream of the check valve 14 can be set to a predetermined low pressure or high pressure. it can.

  Thus, by providing the throttle portion 35 in the fuel merging passage 53 provided independently of the fuel supply passage 31 and generating a negative pressure in the merging portion 34, the configuration of the fuel supply device 1 is prevented from becoming complicated. Thus, the fuel pressure on the downstream side of the check valve 14 can be adjusted, and the manufacturing cost of the fuel supply device 1 can be prevented from increasing. Other effects are the same as those of the first embodiment.

  In each of the above embodiments, the flow control valve 37 that varies the amount of fuel flowing through the branch passage 33 is provided. However, a control valve 37 that opens and closes the branch passage 33 may be provided instead of the flow control valve 37. (In this case, the flow control valve indicated by reference numeral 37 in FIGS. 1 to 5 is referred to as a control valve 37).

  That is, the ECU 8 is based on detection information from the air-fuel ratio sensor 41 and the engine speed sensor 42, when the engine 2 is in an idling operation, or when the engine 2 is in a steady operation where fluctuations in the speed and load are small. When it is determined that the engine 2 is in an operating region where the fuel consumption is small, the control valve 37 is closed to prevent fuel from flowing into the branch passage 33 and the fuel merge passage 53.

  At this time, since no negative pressure is generated in the merging portion 34, the movable valve body portion 25 is opened when the operating pressure P acting on the movable valve body portion 25 becomes larger than the urging force of the compression coil spring 27. In this case, by setting the biasing force of the compression coil spring 27 to a low pressure, the fuel in the pressure regulating chamber 23 and the fuel pressure between the check valve 14 and the injector 5 are set to the low pressure side.

  Further, the ECU 8 is based on the detection information from the air-fuel ratio sensor 41 and the engine speed sensor 42 and is in an operating region where the fuel consumption of the engine 2 is large, such as during acceleration when the engine 2 speed and load fluctuations are large. If the control valve 37 is determined to be, the control valve 37 is opened to supply fuel from the fuel supply passage 31 to the branch passage 33, or to the fuel junction passage 53 from the second discharge port 51b.

  At this time, since the fuel passes through the throttle portion 35, a negative pressure is generated in the merging portion 34, and the movable valve body portion 25 of the pressure regulating member 22 is sucked in the valve closing direction. For this reason, the valve opening pressure of the movable valve body part 25 becomes large, and the movable valve body part 25 becomes difficult to open.

  For this reason, the fuel in the pressure regulating chamber 23 and the fuel pressure between the check valve 14 and the injector 5 are set on the high pressure side. At this time, the fuel in the fuel tank main body 3 is sucked into the sub cup 4 through the communication hole 4 a by the negative pressure generated in the junction 34.

  Even in this case, the fuel pressure downstream of the check valve 14 can be set to a low pressure or a high pressure by using the negative pressure generated in the junction, and the configuration of the fuel supply device 1 is prevented from becoming complicated. Thus, an increase in the manufacturing cost of the fuel supply device 1 can be prevented.

In the fuel supply device 1 shown in FIG. 5, in order to prevent the load in the fuel pump 51 from increasing due to the high pressure in the fuel merging passage 53 when the control valve 37 is closed. A check valve may be provided on the fuel junction passage 53 on the downstream side of the second discharge port 51b.
In each of the above embodiments, the fuel supply device 1 is accommodated in the sub-cup 4, but may be accommodated in the fuel tank body 3.
In the present embodiment, the throttle portion 35 is provided on the branch passage 32 on the upstream side of the merging portion 34. It may be provided in the junction part 34 or on the downstream side of the junction part 34.

  The embodiment disclosed this time is illustrative in all respects and is not limited to this embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

  As described above, the fuel supply device according to the present invention can adjust the fuel pressure supplied to the fuel injection valve by preventing the configuration from becoming complicated, and can prevent the manufacturing cost from increasing. This is useful as a fuel supply device having a pressure regulator capable of adjusting the pressure of the fuel while introducing the fuel supplied from the fuel pump to the fuel injection valve of the internal combustion engine.

1 Fuel supply device 2 Engine (internal combustion engine)
3 Fuel tank body 4 Sub cup 4a Communication hole 5 Injector (fuel injection valve)
11, 51 Fuel pump 20 Pressure regulator 21 Housing 21a Fuel introduction port (fuel introduction passage)
21b Fuel outlet (fuel outlet passage)
22 Pressure adjusting member 23 Pressure adjusting chamber (fuel introduction passage)
27 Compression coil spring (biasing means)
28a Discharge hole (fuel discharge passage)
31 Fuel supply passage 32 Branch passage (branch passage)
33 Branch passage (fuel merge passage)
34 Junction part 35 Restriction part 37 Flow control valve 51a First discharge port 51b Second discharge port 53 Fuel merge passage

Claims (5)

A pressure regulator capable of introducing the fuel supplied from the fuel pump to the fuel injection valve of the internal combustion engine and adjusting the pressure of the fuel;
The pressure regulator includes a housing in which a fuel introduction passage for introducing fuel and a fuel discharge passage for discharging fuel are formed, and the fuel introduction passage and the fuel discharge according to the fuel pressure in the fuel introduction passage inside the housing. A fuel supply comprising a partition-shaped pressure regulating member that communicates with and shuts off the passage, and biasing means that biases the pressure regulating member in a direction that shuts off the fuel introduction passage and the fuel discharge passage. A device,
A fuel supply passage for supplying fuel discharged from the fuel pump to the fuel injection valve;
A branch passage branched from the fuel supply passage and introducing fuel supplied from the fuel pump to the fuel supply passage into the fuel introduction passage of the pressure regulator;
A fuel merging passage having a merging portion for merging fuel discharged from the fuel pump and fuel discharged from the fuel discharge passage;
The fuel supply device, wherein the fuel junction passage has a throttle portion.   The fuel supply device according to claim 1, further comprising a flow rate control valve that is provided on the fuel merging passage and variably controls the amount of fuel flowing through the fuel merging passage.   The fuel joining passage is branched from the fuel supply passage, and the fuel discharged from the fuel pump is supplied to the fuel joining passage through the fuel supply passage. Fuel supply system.   The fuel pump includes a first discharge port that discharges fuel to the fuel supply passage, and a second discharge port that discharges fuel to the fuel merge passage, and the fuel merge passage includes the first discharge port. The fuel supply apparatus according to claim 1, wherein fuel discharged from two discharge ports is supplied to the junction. A sub-cup that accommodates the fuel pump and the pressure regulator therein, and is accommodated in a fuel tank body that stores fuel;
5. The fuel supply device according to claim 1, wherein the sub cup has a communication hole that communicates the fuel tank main body and the merging portion. 6.

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