JP5071364B2 - Fuel supply device - Google Patents

Description

  The present invention relates to a fuel supply device that supplies fuel to an internal combustion engine such as a diesel engine.

[Conventional technology]
Conventionally, fuel pumped up from a fuel tank installed in a vehicle such as an automobile is pressurized by a fuel pump and injected from a fuel injection nozzle into a combustion chamber of each cylinder of an internal combustion engine (engine) such as a diesel engine. As a fuel supply device for an internal combustion engine, a common rail for accumulating fuel discharged from a fuel pump is provided, and the fuel accumulated in the common rail is distributed and supplied to a fuel injection valve (injector) mounted for each cylinder of the engine. An accumulator fuel injection device that injects fuel into a combustion chamber of each cylinder of an engine from an injection hole formed on the tip end side in the axial direction of each injector is known.

In such a fuel supply apparatus, metal ions are eluted into the fuel from a fuel supply pipe (metal pipe) or the like in contact with the fuel in a fuel supply path extending from the fuel tank to the injector. This metal ion may be sent to the internal flow path of the injector and may be deposited and deposited on a minute clearance portion such as a sliding portion of the injector.
In addition, as fuel injected from an injector to an engine, fuels having different properties are used in various regions of the world, and fuel diversification is progressing. In addition, the fuel originally contains various metal components as impurities (for example, trace amounts of metal ions such as Na and K), while a fatty acid such as oleic acid is added as a lubricant. For this reason, an unexpected reaction product of a metal component and a component in the fuel may be generated in the fuel. For example, a salt reaction may occur between a metal ion and a fatty acid, and a fatty acid metal salt may be generated.

When such an unexpected reaction product of the metal component and the component in the fuel is deposited and deposited in a minute clearance portion such as a sliding portion of the injector, there is a problem that the injector malfunctions.
In view of this, a fuel supply path from the fuel tank to the injector, in particular, a fuel supply pipe connecting the fuel tank and the fuel filter is provided, and metal ion removing means for separating and removing metal ions contained in the fuel from the fuel is provided. A fuel supply device has been proposed (see, for example, Patent Document 1). The metal ion removing means includes a housing integrally formed in the middle of a fuel supply pipe connecting the fuel tank and the fuel filter, and a plurality of ion exchange resin particles filled in a filling chamber of the housing. ing.

[Conventional technical problems]
However, in the fuel supply device described in Patent Document 1, a specific implementation method is not shown as to how the metal ion removing means composed of a plurality of ion exchange resin particles is installed in the fuel supply pipe. .
In the fuel supply device described in Patent Document 1, a metal ion made of a plurality of ion exchange resin particles is provided in a fuel supply path from the fuel tank to the injector, particularly in a fuel supply pipe connecting the fuel tank and the fuel filter. The structure which installs a removal means is disclosed. In this case, there is a problem that the pressure loss with respect to the fuel flow from the fuel tank to the engine is large and the energy loss with respect to the pump efficiency of the fuel pump is large.

Also, for the purpose of improving the performance of the metal ion removing means, if the amount of ion exchange resin particles mounted in the fuel supply pipe is increased, the flow resistance of the fuel supply pipe increases, so the amount of ion exchange resin mounted is reduced. It cannot be secured sufficiently. Thereby, there exists a problem that the further improvement of the removal effect of a metal ion cannot be expected.
Further, in the fuel supply device described in Patent Document 1, the pipe layout of the fuel supply pipe extending from the fuel tank to the injector must be changed significantly from the existing pipe layout (pipe layout conventionally implemented). However, there is a problem that the cost increases.
JP 2006-105092 A

An object of the present invention is to provide a fuel supply device that can eliminate a pressure loss with respect to a fuel flow supplied from a fuel tank to an internal combustion engine. Further, the piping layout of the fuel return pipe, is to provide a fuel supply apparatus capable of making it possible to correspond with minimal changes to existing piping layout.

  According to the first aspect of the present invention, the metal ion removing means for removing the metal component (metal ions) eluted in the fuel in the fuel return pipe for returning the (surplus) fuel from the fuel supply device to the fuel tank. By disposing, it is possible to eliminate factors that increase pressure loss and flow path resistance with respect to the fuel flow supplied from the fuel tank to the internal combustion engine. In addition, the pipe layout of the fuel return pipe can be accommodated with minimal changes to the existing pipe layout (metal ion removal means can be installed in the fuel return pipe), thus reducing costs. Can do.

According to the present invention , the fuel supply device includes a low-pressure fuel pump that pumps fuel from the fuel tank, a high-pressure fuel pump that pressurizes the fuel supplied from the low-pressure fuel pump, and fuel supplied from the high-pressure fuel pump. It has a fuel injection valve that injects into the internal combustion engine. In addition to these fuel supply devices, a common rail that supplies fuel supplied from the high-pressure fuel pump to the fuel injection valve may be installed between the high-pressure fuel pump and the fuel injection valve. Further, a fuel supply pipe extending from the fuel tank or the low pressure fuel pump to the fuel injection valve through the high pressure fuel pump may be added to the fuel supply device.

Furthermore, according to the present invention , in addition to the above-described configuration , the fuel supply device particularly has a fuel pressure regulating valve that regulates the pressure of the fuel discharged from the low pressure fuel pump. The fuel return pipe has a return pipe that returns (surplus) fuel flowing out from the fuel pressure regulating valve to the fuel tank. Moreover, the metal ion removal means has an ion exchange resin filled in the return pipe. As a result, it is possible to eliminate factors that increase pressure loss and flow path resistance with respect to the fuel flow supplied from the fuel tank to the internal combustion engine. Further, since the ion exchange resin can be arranged in the return pipe, a sufficient amount of the ion exchange resin can be secured. Thereby, the further improvement of the removal effect of a metal component can be aimed at.

The best mode for carrying out the present invention is to eliminate the pressure loss with respect to the fuel flow supplied from the fuel tank to the internal combustion engine, and to minimize the piping layout of the fuel return piping relative to the existing piping layout. The purpose of making it possible to cope with this change was realized by adopting a specific implementation method of arranging metal ion removal means in the fuel return pipe that returns the (surplus) fuel from the fuel supply equipment to the fuel tank .
Hereinafter, specific embodiments will be described with reference to the drawings for four examples. However, Examples 1, 3, and 4 are reference examples showing an example to which the present invention is not applied, and Example 2 shows an example to which the present invention is applied.

[Configuration of Example 1]
1 to 3 show a first embodiment of the present invention, and FIG. 1 shows a fuel supply device for an internal combustion engine.

A fuel supply device for an internal combustion engine according to this embodiment is mounted in an engine room of a vehicle such as an automobile, and is used for an internal combustion engine (engine) such as a diesel engine having a plurality of cylinders (for example, first to fourth cylinders). It is comprised by the common rail type fuel injection system (accumulation type fuel injection device) known as a fuel injection system. This common rail fuel injection system includes a fuel supply device that supplies fuel to the engine from the fuel storage chamber of the fuel tank, and a fuel return that returns excess fuel overflowed or discharged from the fuel supply device to the fuel storage chamber of the fuel tank. A pipe and an ion exchange filter installed in the fuel return pipe are provided.
The fuel tank has a tank body 1 in which a fuel storage chamber is formed. Diesel fuel (light oil) is stored in the fuel storage chamber of the tank body 1 of the fuel tank. A sub tank 2 may be installed in the tank body 1 of the fuel tank (see FIGS. 5 to 7).
The ion exchange filter is composed of a housing 3 constituting a part of the fuel return pipe, ion exchange resin particles 4 filled in a resin filling chamber of the housing 3, and the like.

The fuel supply device is a fuel injection device mounted in an engine room of a vehicle such as an automobile, and is a feed pump having a known structure that pumps low-pressure fuel from a fuel storage chamber of a tank body 1 of a fuel tank through a fuel filter 11 ( A supply pump (high-pressure fuel pump) 12 having a built-in low-pressure fuel pump, a common rail 13 into which high-pressure fuel is introduced from the discharge port of the supply pump 12, a pressure limiter 14 attached to a leak port of the common rail 13, A plurality (four in this example) of injectors (fuel injection valves) 15 to which high pressure fuel is distributed and supplied from each fuel outlet of the common rail 13 and a fuel supply pipe extending from the fuel tank to the plurality of injectors 15 are provided. Yes.
Here, the common rail fuel injection system is configured to inject and supply high pressure fuel accumulated in the common rail 13 into the combustion chamber of each cylinder of the engine via each injector 15.

The fuel supply pipe is supplied from a supply pipe (low pressure fuel pipe) 21 that forms a fuel supply passage for supplying low pressure fuel from the fuel storage chamber of the tank body 1 of the fuel tank to the fuel filter 11, and from an outlet port of the fuel filter 11. A supply pipe (low pressure fuel pipe) 22 that forms a fuel supply passage for supplying low pressure fuel to the pump 12, and a supply pipe that forms a fuel supply passage for supplying high pressure fuel from the discharge port of the supply pump 12 to the common rail 13 ( High pressure fuel pipe) 23 and a branch pipe (high pressure fuel pipe) 24 that forms a fuel supply passage for supplying high pressure fuel from each fuel outlet of the common rail 13 to each injector 15.
Note that the tip of the supply pipe 21 of the fuel supply pipe on the fuel tank side is immersed in the fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank. That is, the supply pipe 21 of the fuel supply pipe is such that the fuel suction port of the supply pipe 21 is positioned below the vehicle level in the vehicle vertical direction from the level of the fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank. Attached to the fuel tank.

  The fuel filter 11 has a filter element and a filter case for housing the filter element. The filter element is a filter element or other filter-like material installed in the internal space formed in the filter case, and impurities contained in the fuel flowing from the fuel storage chamber of the tank body 1 of the fuel tank. (Solid matter such as dust and rust, sludge and moisture such as carbon and gum-like substances) are filtered or captured and separated and removed from the fuel. The filter case is formed with an inlet (inlet port) connected to the downstream end of the supply pipe 21 in the fuel flow direction and an outlet (outlet port) connected to the upstream end of the supply pipe 22 in the fuel flow direction. Yes.

  The supply pump 12 has one or two (or three or more) pumping systems that pressurize low-pressure fuel sucked from the fuel storage chamber of the tank body 1 of the fuel tank through the supply pipe 21, the fuel filter 11, and the supply pipe 22. Provided, that is, the pump element is provided with one cylinder or two cylinders (or three cylinders or more), and one solenoid valve (not shown) is used to control the fuel discharge amount of one or two (or three or more) pumping systems, This is a high-pressure fuel pump of a type that is controlled by metering the amount of fuel sucked into each fuel pressurizing chamber. The supply pump 12 includes a feed pump (not shown) having a known structure, a pump drive shaft (cam shaft: not shown) that drives the feed pump, and a pump drive shaft that is rotatable through a bearing. A supporting pump housing (not shown), a cam (not shown) driven by a pump drive shaft, and a reciprocating linear motion between the top dead center and the bottom dead center driven by the cam; or 2 (or 3 or more) plungers (not shown) and a cylinder head fixed to the pump housing and having 1 or 2 (or 3 or more) fuel pressurizing chambers formed therein (see FIG. Not shown).

The feed pump pumps low pressure fuel from the fuel storage chamber of the tank body 1 of the fuel tank through the supply pipe 21, the fuel filter 11, and the supply pipe 22 by rotating the pump drive shaft with the rotation of the crankshaft of the engine. This is a low-pressure fuel pump. Further, the supply pump 12 has one or two (or three or more) fuel pressurizing chambers from the supply pipe 22 through the feed pump and the fuel suction flow path as each plunger reciprocates in the cylinder head. This is a high-pressure fuel pump that pressurizes the low-pressure fuel sucked into the cylinder to increase the pressure.
The plunger is slidably supported in the sliding hole of the cylinder head.
The supply pump 12 is provided with a check valve structured intake valve upstream of each fuel pressurizing chamber in the fuel flow direction. The supply pump 12 is provided with a check valve structure discharge valve downstream of each fuel pressurizing chamber in the fuel flow direction. When this discharge valve is opened, high-pressure fuel is discharged from the discharge port of the supply pump 12 toward the common rail 13.

Further, the supply pump 12 is provided with a leak port so that the internal fuel temperature does not become high. Leak fuel (surplus fuel) from the supply pump 12 passes through the fuel return pipe and the tank body 1 of the fuel tank. Returned to the fuel storage chamber.
Here, in the middle of the fuel intake passage formed inside the supply pump 12 and extending from the feed pump to one or two (or three or more) fuel pressurizing chambers, the respective intake valves are connected. A solenoid valve for adjusting the amount of fuel sucked into the fuel pressurizing chamber is attached. This solenoid valve is configured to be electronically controlled by a pump drive current applied from an engine control unit (ECU). Thereby, the fuel discharge amount discharged from the discharge port of the supply pump 12 is controlled.

The common rail 13 is a pressure accumulating container for accumulating high-pressure fuel corresponding to the fuel injection pressure, and has a fuel inlet (inlet port) connected to the discharge port of the supply pump 12 via the supply pipe 23. Further, the common rail 13 has a fuel outlet (outlet port) connected to each injector 15 via a plurality of branch pipes 24. Further, the leaked fuel (surplus fuel) from the common rail 13 is returned to the fuel storage chamber of the tank body 1 of the fuel tank through the fuel return pipe.
Here, a pressure limiter 14 is liquid-tightly attached between the leak port of the common rail 13 and the fuel return pipe. The pressure limiter 14 is a pressure relief valve that opens when the internal pressure of the common rail 13 (so-called common rail pressure) exceeds a set value (limit set pressure) to keep the internal pressure of the common rail 13 below the limit set pressure. is there.

  As shown in FIGS. 1 to 3, the plurality of injectors 15 mounted corresponding to each cylinder of the engine injects high-pressure fuel accumulated in the common rail 13 directly into the combustion chamber in the form of a mist. This is a direct injection type fuel injection valve to be supplied. The injector 15 is connected to the downstream end of the plurality of branch pipes 24 branched from the common rail 13 in the fuel flow direction, and injects fuel into the combustion chamber of each cylinder of the engine, and the fuel injection nozzle This is an electromagnetic fuel injection valve composed of a nozzle needle 31 that is a valve element of the above and an electromagnetic valve that drives a command piston 32 connected to the nozzle needle 31 in the valve opening operation direction. This solenoid valve is configured to be electronically controlled by an injector drive current applied from the ECU. Thereby, the fuel injection amount and the injection timing injected from the injector 15 are controlled.

The fuel injection nozzle includes a nozzle needle 31 that opens and closes a plurality of injection holes, a command piston 32 connected to an axial rear end portion (the upper end portion in the drawing) of the nozzle needle 31, and a nozzle needle 31 that is slidable. A nozzle body 33 having a sliding hole (axial hole) for supporting, and an injector body (hereinafter referred to as a lower body) 34 having a sliding hole (axial hole) for slidably supporting the command piston 32 are provided. (See FIGS. 2 and 3).
Here, the injector 15 of the present embodiment has a rear end in the axial direction of the lower body 34 in a state where the orifice plate 36 is sandwiched between the lower body 34 which is a housing of the fuel injection nozzle and the valve body 35 which is a housing of the electromagnetic valve. By fastening and fixing (fastening and fixing) the retaining nut 37 to the outer periphery of the end portion, the fuel injection nozzle and the solenoid valve are integrally coupled.

The solenoid valve includes a valve seat (orifice plate 36) assembled at the rear end portion in the axial direction of the fuel injection nozzle, and a valve (solenoid valve body) 39 that can be seated on and removed from the orifice plate 36. And an electromagnetic actuator that drives the valve 39 in the valve opening operation direction or the valve closing operation direction. The orifice plate 36 is formed with inlet-side and outlet-side orifices 41 and 42 for adjusting the flow rate of fuel passing therethrough. The outlet orifice 42 constitutes a valve hole of an electromagnetic valve.
The electromagnetic actuator includes a cylindrical valve body 35 that sandwiches an orifice plate 36 with the lower body 34, an armature 43 that is slidably supported in a sliding hole of the valve body 35, and an electromagnetic force that attracts the armature 43. It has a cylindrical electromagnet that generates

The electromagnet includes a solenoid coil (electromagnetic coil) 44 wound around a cylindrical coil bobbin, an external connection terminal (terminal) 45 connected to the electromagnetic coil 44, a stator 46 magnetized by energization of the electromagnetic coil 44, and the like. It is constituted by.
The full lift position of the armature 43 is regulated by a cylindrical stopper 48 that houses a valve spring 39 and a coil spring 47 that biases the armature 43 in the valve closing direction.
A shaft 49 that is slidably supported in a sliding hole that extends in the axial direction of the valve body 35 is formed integrally with the armature 43 on the opposite side to the stator side.

The nozzle needle 31 of the fuel injection nozzle has a body portion (large diameter portion) 51 that is slidably supported in a sliding hole that extends in the axial direction of the nozzle body 33, and has a plurality of nozzles formed on the nozzle body 33. Open and close the injection hole. The command piston 32 has a body portion (large diameter portion) 52 slidably supported in a slide hole extending in the axial direction of the lower body 34, and operates in the vertical direction in the figure in conjunction with the nozzle needle 31. To do. A coil spring 53 that energizes the nozzle needle 31 in the valve closing direction is accommodated in the front end portion (lower end portion in the drawing) of the lower body 34 in the axial direction.
The nozzle body 33 and the lower body 34 are supplied with high-pressure fuel from a pipe joint inlet port 54 connected to the common rail 13 through a bar filter 55 that captures foreign matters mixed in the fuel. Passages 56 to 59 are formed. The fuel supply passages 56 to 59 are high-pressure fuel passages for supplying high-pressure fuel to the fuel reservoir chamber 61 and the pressure control chamber 62.

The fuel reservoir chamber 61 is formed in the central portion of the nozzle body 33 in the axial direction. The pressure control chamber 62 is formed on the rear end side (the upper end side in the figure) of the lower body 34 in the axial direction. The pressure control chamber 62 communicates with the fuel supply passages 56 and 57 via the inlet side orifice 41 formed in the orifice plate 36. The pressure control chamber 62 communicates with a fuel discharge passage 63 formed in the valve body 35 via an outlet-side orifice 42 formed in the orifice plate 36.
A fuel recovery passage 65 is formed in the lower body 34 through which surplus fuel flows from a spring accommodating chamber 64 that accommodates the coil spring 53.
The surplus fuel that has flowed into the fuel recovery passage 65 is returned to the fuel storage chamber of the tank body 1 of the fuel tank through the fuel discharge passages 66 and 67 on the solenoid valve side, the leak port 68, the outlet pipe 69, and the fuel return pipe. The solenoid valve side fuel discharge passages 66 and 67 communicate with the pressure control chamber 62 through the fuel discharge passage 63 and the outlet side orifice 42.

The fuel return pipe is configured to supply excess fuel that overflows or is discharged from the leak port of any two or more of the supply pump 12, the common rail 13, and the plurality of injectors 15 to the fuel of the tank body 1 of the fuel tank. It has a plurality of return pipes 71 to 74 returning to the storage chamber.
Inside the return pipe 71, a first fuel return passage is formed through which surplus fuel from the leak port of the supply pump 12 flows. In addition, a second fuel return passage through which surplus fuel from the leak port (pressure limiter 14) of the common rail 13 flows is formed inside the return pipe 72. In addition, a third fuel return flow path through which surplus fuel from each leak port 68 of the plurality of injectors 15 flows is formed inside the return pipe 73.

In addition, surplus fuel from the leak port (or the pressure limiter 14) of any two or more of the supply pump 12, the common rail 13, and the plurality of injectors 15 is joined into the return pipe 74. After that, a fuel return passage for returning to the fuel storage chamber of the tank body 1 of the fuel tank is formed.
The tip of the return line 74 of the fuel return line on the fuel tank side is immersed in the fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank. That is, the return pipe 74 of the fuel return pipe is connected to the fuel tank so that the discharge port is located below the liquid level of the fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank. It is attached.

The ion exchange filter has a cylindrical housing 3 provided in the middle of the return pipe 74 of the fuel return pipe and a resin-filled chamber of the housing 3 so that the fuel flows from the upper side to the lower side in the direction of gravity (the vehicle vertical direction). It is comprised by the ion exchange resin particle 4 etc. with which it fills.
The resin filling chamber of the housing 3 is larger in size in the height direction along the vehicle vertical direction than in the vehicle width direction or lateral direction along the vehicle front-rear direction, and more upstream and downstream in the fuel flow direction than the housing 3. This is a space larger than the cross-sectional area of the fuel return flow path of the return pipe 74 formed in A fuel inlet for introducing fuel into the resin filling chamber is formed on the upstream side of the housing 3 in the fuel flow direction. Further, a fuel outlet for leading the fuel from the resin filling chamber is formed on the downstream side of the housing 3 in the fuel flow direction.

A mesh plate or a mesh filter (not shown) is installed at the fuel inlet and the fuel outlet of the housing 3 for the purpose of preventing the ion exchange resin particles 4 from flowing out or scattering and ensuring the fuel flow. ing.
The ion exchange resin particles 4 capture metal ions eluted in the fuel in the fuel return pipe by exchange adsorption or the like. That is, the ion exchange resin particles 4 are substances (spherical particles) capable of separating and removing metal components (metal ions) contained in the fuel from the fuel.

[Operation of Example 1]
Next, the operation of the fuel supply device (common rail fuel injection system) for the internal combustion engine of this embodiment will be briefly described with reference to FIGS.

When the pump drive shaft of the supply pump 12 is driven and rotated by the crankshaft of the engine, the feed pump built in the supply pump 12 rotates with the rotation of the pump drive shaft. Thereby, the low-pressure fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank is sucked from the fuel suction port of the supply pipe 21 and flows into the fuel filter 11 through the supply pipe 21.
When the low-pressure fuel that has flowed into the internal space from the inlet of the filter case passes through the filter element installed in the internal space, impurities contained in the fuel are separated and removed. Then, the low-pressure fuel that has been filtered and purified by the filter element flows out from the outlet of the filter case.
The low-pressure fuel flowing out from the fuel filter 11 is sucked into the feed pump through the supply pipe 22. The feed pump pressurizes and discharges the low-pressure fuel sucked from the fuel storage chamber of the tank body 1 of the fuel tank to the solenoid valve side.

Further, the cam rotates with the rotation of the pump drive shaft, and the plunger reciprocates with the rotation of the cam. When the plunger at the top dead center moves toward the bottom dead center with the rotation of the cam, the fuel discharged from the feed pump flows into the fuel pressurizing chamber through the electromagnetic valve and the suction valve. When the plunger that has reached the bottom dead center moves again toward the top dead center, the intake valve closes and the fuel pressure in the fuel pressurizing chamber increases. When the fuel pressure in the fuel pressurizing chamber rises, the discharge valve opens and high pressure fuel is discharged.
In this way, the supply pump 12 pressurizes the low-pressure fuel pumped up by the feed pump in the fuel pressurization chamber to increase the pressure, discharges the high-pressure fuel from the discharge port, and supplies the high-pressure fuel to the common rail 13.
The high-pressure fuel discharged from the discharge port of the supply pump 12 flows into the common rail 13 (accumulation chamber) from the fuel inlet via the supply pipe 23 and is temporarily accumulated in the accumulation chamber.

  Here, at the injection timing of the injector 15 mounted on the first cylinder among the plurality of cylinders (first to fourth cylinders) of the engine, energization to the electromagnetic coil 44 of the solenoid valve of the injector 15 is started. The Thus, when the electromagnetic coil 44 of the electromagnetic valve of the injector 15 is energized, an electromagnetic force is generated in the electromagnet composed of the electromagnetic coil 44 and the stator 46. The armature 43 is attracted to the magnetic pole surface side of the stator 46 by the electromagnetic force of the electromagnet. Then, the armature 43 moves in the direction approaching the magnetic pole surface of the stator 46 (one side in the axial direction), and the armature body of the armature 43 abuts on the restriction surface of the stopper body of the stopper 48. Thereby, the position of the armature 43 is regulated at the full lift position.

At this time, high pressure fuel is introduced into the pressure control chamber 62 upstream of the valve 39 in the fuel flow direction from the common rail 13 through the inlet side orifice 41. The fuel discharge passage 63 downstream in the fuel flow direction from the valve 39 communicates with the fuel tank (low pressure side of the fuel system) via the fuel discharge passages 66 and 67, the leak port 68, and the outlet pipe 69. ing.
For this reason, since the fuel pressure is higher on the upstream side in the fuel flow direction than on the valve 39 than on the downstream side in the fuel flow direction than on the valve 39, the armature 43 moves (lifts) upward in the axial direction. Accordingly, the valve 39 is detached from the valve seat of the orifice plate 36, and the outlet side orifice 42 of the orifice plate 36 is opened. Therefore, the fuel filled in the pressure control chamber 62 passes from the pressure control chamber 62 to the fuel tank via the outlet side orifice 42 → the fuel discharge passage 63 → the fuel discharge passages 66 and 67 → the leak port 68 → the outlet pipe 69. Returned.

Along with the opening operation of the solenoid valve itself, the fuel pressure in the pressure control chamber 62 (the oil pressure acting in the direction in which the nozzle needle 31 is pushed down (the valve closing direction)) is reduced, and the fuel in the fuel reservoir chamber 61 is reduced. The pressure (the oil pressure acting in the direction in which the nozzle needle 31 is pushed up (the valve opening direction)) acts on the oil pressure in the pressure control chamber 62 in the urging force of the coil spring 53 (the direction in which the nozzle needle 31 is pushed down (the valve closing direction)). (The biasing force to be applied) is greater than the resultant force.
Thereby, since the nozzle needle 31 separates from the valve seat (seat surface) of the nozzle body 33, a plurality of injection holes are opened. That is, when the injector 15 mounted on the first cylinder of the engine is opened, the high-pressure fuel accumulated in the common rail 13 (accumulation chamber) passes through the branch pipe 24 to the inside of the injector 15 (fuel supply passage). 56 to 59, the fuel reservoir chamber 61, the pressure control chamber 62, etc.), and is injected and supplied from the plurality of injection holes into the combustion chamber of the first cylinder of the engine through the fuel reservoir chamber 61. Therefore, fuel injection into the combustion chamber of the first cylinder of the engine is started.

When the command injection period elapses from the injection timing, energization to the electromagnetic coil 44 of the electromagnetic valve is stopped. Then, the armature 43 is moved away from the magnetic pole surface of the stator 46 by the urging force of the coil spring 47, and the valve 39 is pressed against the valve seat of the orifice plate 36.
As a result, the outlet-side orifice 42 is closed, so that the high-pressure fuel supplied from the common rail 13 to the pressure control chamber 62 via the fuel supply passages 56 and 57 and the inlet-side orifice 41 is filled in the pressure control chamber 62. To do. Along with this, the fuel pressure in the pressure control chamber 62 increases. When the resultant force obtained by adding the urging force of the coil spring 53 to the fuel pressure in the pressure control chamber 62 becomes larger than the fuel pressure in the fuel reservoir chamber 61, the nozzle needle 31 is applied to the valve seat (seat surface) of the nozzle body 33. In order to be seated, a plurality of injection holes are closed. That is, when the injector 15 mounted on the first cylinder of the engine is closed, the fuel injection into the combustion chamber of the first cylinder of the engine is finished.

Therefore, in the internal combustion engine fuel supply device (common rail fuel injection system) of the present embodiment, the solenoid coil 44 of the solenoid valve of the injector 15 is energized and the nozzle needle 31 is formed at the tip of the nozzle body 33 in the axial direction. While the plurality of injection holes are opened, the high-pressure fuel accumulated in the common rail 13 (accumulation chamber) is injected and supplied into the combustion chamber of the first cylinder of the engine.
Further, high-pressure fuel is supplied to the inside of the injector 15 (fuel supply passages 56 to 59, the fuel reservoir chamber 61, the pressure control chamber 62, etc.) mounted on the other cylinders (second to fourth cylinders) excluding the first cylinder of the engine. Are distributed and sequentially injected into the combustion chambers of the second to fourth cylinders of the engine. As a result, the engine is operated.

Here, surplus fuel (return fuel) overflowed or discharged from the leak port of the supply pump 12 flows through the return pipe 71 and flows into the return pipe 74. Further, surplus fuel (return fuel) overflowed or discharged from the leak port (pressure limiter 14) of the common rail 13 flows through the return pipe 72 and flows into the return pipe 74. Further, surplus fuel (return fuel) overflowed or discharged from each leak port 68 and each outlet pipe 69 of the plurality of injectors 15 flows through the return pipe 73 and flows into the return pipe 74.
Then, surplus fuel from the leak port (or pressure limiter 14) of any two or more fuel supply devices among the supply pump 12, the common rail 13, and the plurality of injectors 15 passes through the return pipe 74 and passes through the ion exchange filter. Flows into the interior.

The surplus fuel that has passed through the mesh plate or mesh filter held and fixed to the fuel inlet of the housing 3 and has flowed into the resin filling chamber of the housing 3 contacts a large number of ion exchange resin particles 4 filled in the resin filling chamber. To do. At this time, metal components (metal ions) eluted in the surplus fuel that has flowed into the resin-filled chamber of the housing 3 are captured by a large number of ion-exchange resin particles 4 by exchange adsorption or the like. That is, the metal component (metal ion) contained in the surplus fuel is separated and removed from the surplus fuel by the ion removing ability of the ion exchange resin particles 4. The surplus fuel from which the metal components (metal ions) have been separated and removed by the ion exchange resin particles 4 flows out of the housing 3 through the mesh plate or mesh filter held and fixed at the fuel outlet of the housing 3.
Excess fuel flowing out from the ion exchange filter is returned to the fuel storage chamber of the tank body 1 of the fuel tank via the return pipe 74.

[Effect of Example 1]
As described above, in the fuel supply device (common rail fuel injection system) for the internal combustion engine of this embodiment, any two or more of the fuel supply devices among the supply pump 12, the common rail 13, and the plurality of injectors 15 are used. An ion exchange filter is disposed in a fuel return pipe that forms a fuel return passage for returning the fuel to the fuel storage chamber of the tank body 1 of the fuel tank after surplus fuel from the leak port (or the pressure limiter 14) is merged. Yes. Specifically, the housing 3 of the ion exchange filter is installed in the middle of the return pipe 74 of the fuel return pipe, and a large number of ion exchanges excellent in the ability to remove metal ions eluted in the fuel in the resin filling chamber of the housing 3. Resin particles 4 are filled.

  Thus, as a specific implementation method of the ion exchange filter for the fuel supply device of the internal combustion engine, an implementation method of arranging the ion exchange filter filled with the ion exchange resin particles 4 in the resin filling chamber of the housing 3 in the fuel return pipe. Is adopted (implemented). Thereby, even when an unexpected reaction product of a metal component eluted in the fuel and a component in the fuel, for example, a fatty acid metal salt is generated, the ion exchange resin particles arranged in the fuel return pipe The metal ions are separated and removed from the fuel by being exchanged by 4. Thereby, clean fuel from which metal ions are not eluted can be sucked from the fuel suction port of the supply pipe 21 of the fuel supply pipe in the fuel storage chamber of the tank body 1 of the fuel tank.

  Therefore, an unexpected reaction product of the metal component and the component in the fuel, such as a fatty acid metal salt, is generated by the sliding portion of the supply pump 12 (between the hole wall surface of the sliding hole of the solenoid valve and cylinder head and the outer peripheral surface of the plunger). Or a sliding portion formed between the sliding wall portion of the injector 15 (the wall surface of the sliding hole of the valve body 35 of the solenoid valve and the outer peripheral surface of the shaft 49 of the armature 43). Dynamic clearance or the sliding clearance formed between the hole wall surface of the sliding hole of the nozzle body 33 of the fuel injection nozzle and the outer peripheral surface of the body portion 51 of the nozzle needle 31 or the sliding hole of the lower body 34 of the fuel injection nozzle. It is possible to suppress the problem of depositing or depositing on the hole wall surface and the sliding clearance formed between the outer peripheral surface of the body portion 52 of the command piston 32. Accordingly, it is possible to prevent the occurrence of malfunctions such as malfunction of the supply pump 12 or the injector 15 due to the metal component biting into the sliding portion of the supply pump 12 or the injector 15.

Accordingly, the fuel storage chamber of the tank body 1 of the fuel tank is compared with the conventional technique in which the ion exchange resin particles are installed in the fuel supply pipe for supplying fuel from the fuel storage chamber of the tank body 1 of the fuel tank to the injector 15. Therefore, there are no factors that increase the pressure loss or flow path resistance of the fuel flow supplied to the injector 15. That is, there is no pressure loss for fuel supply from the fuel storage chamber of the tank body 1 of the fuel tank to the combustion chamber of each cylinder of the engine, and energy loss is reduced.
Further, after surplus fuel overflowed or discharged from the leak port (or the pressure limiter 14) of any two or more of the supply pump 12, the common rail 13, and the plurality of injectors 15 is joined, the fuel The piping layout of the return pipes 71 to 74 that form the fuel return passage returning to the fuel storage chamber of the tank body 1 of the tank can be accommodated with minimal changes to the existing piping layout (ion exchange in the fuel return pipe Therefore, it is possible to reduce the cost.

Further, the ion exchange filter is configured by a large number of ion exchange resin particles 4 filled in a resin filling chamber of the housing 3 installed in the middle of the return pipe 74 of the fuel return pipe.
Further, since the ion exchange resin particles 4 can be arranged in the resin filling chamber of the housing 3 installed in the middle of the return pipe 74, the pressure loss of the fuel flow flowing in the fuel supply flow path of the fuel supply pipe and The effect on the increase in channel resistance is very small. This makes it possible to place more ion exchange resin particles 4 in the return pipe 74 of the fuel return pipe for the purpose of increasing the number of times of contact between the ion exchange resin particles 4 and the fuel. A sufficient amount of the exchange resin particles 4 can be secured. Therefore, it is possible to further improve the removal effect (ability) of the metal component (metal ion).

  FIG. 4 shows a second embodiment of the present invention and shows a fuel supply device for an internal combustion engine. The fuel supply device of this embodiment includes a feed pump (low pressure fuel pump) 5 having a known structure that pumps low pressure fuel from the fuel storage chamber of the tank body 1 of the fuel tank, and the pressure of the fuel discharged from the feed pump 5. A fuel pressure regulating valve 6 that regulates pressure, a supply pump 12 that sucks and pressurizes low-pressure fuel discharged from the feed pump 5 via the fuel filter 11, and high-pressure fuel discharged from the discharge port of the supply pump 12 are introduced. Common rail 13, pressure limiter 14 mounted on the leak port of common rail 13, a plurality of injectors 15 to which high-pressure fuel is distributed and supplied from each fuel outlet of common rail 13, and a fuel tank to a plurality of injectors 15. And an extended fuel supply pipe. The supply pump 12 may not include a feed pump driven by a pump drive shaft as shown in the first embodiment.

The fuel supply pipe has supply pipes 21 to 23 and a branch pipe 24 for supplying fuel from the discharge port of the feed pump 5 to the plurality of injectors 15. A fuel supply passage for supplying low-pressure fuel from the discharge port of the feed pump 5 to the fuel filter 11 is formed inside the supply pipe 21 of this embodiment. A T-shaped branch portion 25 is provided in the middle of the supply pipe 21 of the fuel supply pipe. A branch pipe 26 branches from the branch portion 25.
The fuel return pipe is a fuel tank for surplus fuel that overflows or is discharged from the leak port (or the pressure limiter 14) of any two or more of the supply pump 12, the common rail 13, and the plurality of injectors 15. Return pipes 71 to 74 for returning to the fuel storage chamber of the tank body 1 and a return pipe 75 for returning the fuel flowing out from the fuel pressure regulating valve 6 to the fuel storage chamber of the tank body 1 of the fuel tank. The return pipe 75 is connected to the downstream end in the fuel flow direction of the branch pipe 26 that branches from the middle of the supply pipe 21 of the fuel supply pipe via the fuel pressure regulating valve 6.

The feed pump 5 is an in-tank type electric fuel pump installed in the fuel storage chamber of the tank body 1 of the fuel tank, and rotates a pump part made of an impeller or the like by a driving force of a motor part made of a DC motor or the like. Thus, the low-pressure fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank is sucked up (inhaled), pressurized and discharged.
The feed pump 5 is immersed in the fuel stored in the fuel storage chamber of the tank body 1 of the fuel tank. That is, the feed pump 5 is installed in the fuel storage chamber of the tank main body 1 of the fuel tank so as to be located below the liquid level of the fuel stored in the fuel storage chamber of the tank main body 1 of the fuel tank. Has been.

The fuel pressure regulating valve 6 is installed at the upstream end in the fuel flow direction of the fuel return pipe that returns the fuel to the fuel storage chamber of the tank body 1 of the fuel tank. The fuel pressure regulating valve 6 includes a valve case disposed between the branch pipe 26 and the return pipe 75, a valve 7 for opening and closing a valve hole formed in the valve case, and the valve 7 in a valve closing operation direction. It is composed of an urging spring 8 or the like. Further, the valve 7 of the fuel pressure regulating valve 6 opens overcoming the urging force (spring load) of the spring 8 when the pressure of the low-pressure fuel discharged from the feed pump 5 rises above a set value.
The ion exchange filter includes a cylindrical housing 3 installed in the middle of the return pipe 75 of the fuel return pipe, ion exchange resin particles 4 filled in the resin filling chamber of the housing 3, and the like.

  As described above, in the fuel supply device for an internal combustion engine according to the present embodiment, the valve of the fuel pressure regulating valve 6 connected to the downstream end in the fuel flow direction of the branch pipe 26 branched from the middle of the supply pipe 21 of the fuel supply pipe. When the valve 7 is opened, an ion exchange filter is formed in the fuel return pipe that forms a fuel return passage for returning the low pressure fuel flowing out from the valve case of the fuel pressure regulating valve 6 to the fuel storage chamber of the tank body 1 of the fuel tank. Is arranged. Specifically, the ion exchange filter housing 3 is installed in the middle of the return pipe 75 of the fuel return pipe, and a large number of ion exchanges excellent in the ability to remove metal ions eluted in the fuel in the resin filling chamber of the housing 3. By filling the resin particles 4, the same effect as in the first embodiment can be achieved.

  FIG. 5 shows a third embodiment of the present invention and shows a fuel supply device for an internal combustion engine. The fuel tank of this embodiment has a tank body 1 in which a fuel storage chamber is formed. A sub tank 2 is installed in the tank body 1 of the fuel tank. The subtank 2 has an internal space partitioned into a fuel storage chamber 16 and a fuel return chamber 17. Further, the fuel storage chamber 16 of the sub tank 2 communicates with the fuel storage chamber of the tank body 1, and diesel fuel (light oil) is stored in the fuel storage chamber 16. Further, the fuel return chamber 17 of the sub tank 2 is partitioned from the fuel storage chamber of the tank body 1 and the fuel storage chamber 16 of the sub tank 2, and the fuel return chambers 17 to 74 of the fuel return pipe are connected to the fuel storage chamber 16 of the sub tank 2. It constitutes a fuel return channel through which the fuel going is circulated. Note that the upper end of the sub tank 2 in the direction of gravity (the vehicle vertical direction) is an inlet portion through which fuel flows from the return pipe 74 of the fuel return pipe into the fuel return chamber 17 of the sub tank 2.

As in the first embodiment, the fuel supply device includes a fuel filter 11, a supply pump 12 incorporating a feed pump, a common rail 13, a pressure limiter 14, a plurality of injectors 15, and a fuel supply pipe.
The fuel supply pipe has supply pipes 21 to 23 and a branch pipe 24 for supplying fuel from the fuel storage chamber 16 of the sub tank 2 to the plurality of injectors 15. The tip of the fuel supply pipe 21 on the fuel tank side of the supply pipe 21 is immersed in the fuel stored in the fuel storage chamber 16 of the sub tank 2. In other words, the fuel supply pipe 21 of the fuel supply pipe has a fuel suction port that is closer to the vehicle than the liquid level of the fuel stored in the fuel storage chamber 16 of the sub tank 2 (the liquid level of the fuel stored in the sub tank 2). It is attached to the sub tank 2 so as to be positioned on the lower side in the vertical direction.

  The fuel return pipe supplies the excess fuel that overflows or is discharged from the leak port (or the pressure limiter 14) of any two or more of the supply pump 12, the common rail 13, and the plurality of injectors 15 to the sub tank 2. Return pipes 71 to 74 for returning to the fuel storage chamber 16 are provided. Note that the return pipe 74 of the fuel return pipe has a fuel outlet that is higher than the liquid level of the fuel stored in the fuel storage chamber 16 of the sub tank 2 (the liquid level of the fuel stored in the sub tank 2). It is attached to the sub tank 2 so as to be positioned on the upper side in the vehicle vertical direction.

  The ion exchange filter is constituted by ion exchange resin particles 4 filled in a resin filling chamber in a fuel return chamber 17 of a sub tank 2 installed in a tank body 1 of a fuel tank. In addition, on the upper side and the lower side of the resin filling chamber in the fuel return chamber 17 in the gravity direction (vehicle vertical direction), the ion exchange resin particles 4 are prevented from flowing out or scattered and the fuel is distributed. A mesh plate or a mesh filter (not shown) is installed. The mesh plate or mesh filter installed below the sub tank 2 in the direction of gravity (the vehicle vertical direction) functions as a partition wall that partitions the internal space of the sub tank 2 into a fuel storage chamber 16 and a fuel return chamber 17. . In addition, a resin filling chamber for filling a large number of ion exchange resin particles 4 is formed between mesh plates or mesh filters installed on the upper side and the lower side of the sub tank 2 in the direction of gravity (the vehicle vertical direction).

  As described above, in the fuel supply device for the internal combustion engine of the present embodiment, the leak port (or the pressure limiter 14) of any two or more fuel supply devices among the supply pump 12, the common rail 13, and the plurality of injectors 15 is used. ) From the return pipe 74 of the fuel return pipe for returning the surplus fuel to the fuel storage chamber 16 of the sub tank 2. Specifically, the fuel return is performed in the fuel return chamber 17 of the subtank 2 disposed on the lower side in the vehicle vertical direction of the return pipe 74 of the fuel return pipe, that is, in the subtank 2 installed in the tank body 1 of the fuel tank. A large number of ion exchange resins excellent in the ability to remove metal ions eluted in the fuel in the fuel return chamber 17 constituting the fuel return passage through which the fuel flowing from the return pipe 74 of the pipe toward the fuel storage chamber 16 of the sub tank 2 flows. By filling the particles 4, the same effect as in the first embodiment can be achieved.

  6 to 8 show a fourth embodiment of the present invention, FIG. 6 shows a fuel supply device for an internal combustion engine, and FIGS. 7 and 8 show an ion exchange filter installed in the sub tank. It is a figure.

The fuel supply device includes an electric feed pump 5 that pumps low-pressure fuel from the fuel storage chamber 16 of the sub-tank 2 of the fuel tank, a fuel pressure regulating valve 6 that regulates the pressure of the fuel discharged from the feed pump 5, and a fuel filter. 11, a supply pump 12 that sucks and pressurizes low-pressure fuel discharged from the feed pump 5 through the common pump 13, a common rail 13 into which high-pressure fuel discharged from the discharge port of the supply pump 12 is introduced, and leakage of the common rail 13. A pressure limiter 14 mounted on the port, a plurality of injectors 15 to which high-pressure fuel is distributed and supplied from each fuel outlet of the common rail 13, and a fuel supply pipe extending from the fuel tank to the plurality of injectors 15 are provided. The supply pump 12 may not include a feed pump driven by a pump drive shaft as shown in the first embodiment.
The fuel supply pipe has supply pipes 21 to 23 and a branch pipe 24 for supplying fuel from the discharge port of the feed pump 5 to the plurality of injectors 15.
The fuel return pipe supplies the excess fuel that overflows or is discharged from the leak port (or the pressure limiter 14) of any two or more of the supply pump 12, the common rail 13, and the plurality of injectors 15 to the sub tank 2. Return pipes (first return pipes) 71 to 74 that return to the fuel return chamber 17 and a return pipe (second return pipe) 75 that returns the fuel that has flowed out of the fuel pressure regulating valve 6 to the fuel return chamber 17 of the sub tank 2. ing.

The ion exchange filter is composed of ion exchange resin particles 4 filled in a resin filling chamber in a fuel return chamber 17 of a housing 3 formed integrally with a sub tank 2 installed in a tank body 1 of a fuel tank. ing. In addition, on the upper side and the lower side of the resin filling chamber in the fuel return chamber 17 in the gravity direction (vehicle vertical direction), the ion exchange resin particles 4 are prevented from flowing out or scattered and the fuel is distributed. And mesh plates or mesh filters 76 and 77 are respectively installed. The mesh plate or mesh filter 77 installed below the sub tank 2 in the direction of gravity (vehicle up-down direction) functions as a partition wall that partitions the internal space of the sub tank 2 into a fuel storage chamber 16 and a fuel return chamber 17. To do. In addition, a resin filling chamber for filling a large number of ion exchange resin particles 4 is formed between mesh plates or mesh filters 76 and 77 installed on the upper side and the lower side of the sub tank 2 in the gravity direction (vehicle up-down direction). Is done.
Further, the ion exchange resin particles 4 may be configured to be immersed in the fuel stored in the sub tank 2 when the remaining amount of fuel in the fuel storage chamber of the tank body 1 of the fuel tank is large. In this case, the upper opening of the sub-tank 2 is located on the lower side in the vehicle vertical direction with respect to the liquid level of the fuel stored in the fuel storage chamber of the tank body 1.

The feed pump 5 is an in-tank type electric fuel pump installed in the fuel storage chamber 16 of the sub-tank 2. By rotating a pump unit made of an impeller or the like by a driving force of a motor unit made of a DC motor or the like, The low pressure fuel stored in the fuel storage chamber 16 of the sub tank 2 is sucked up (inhaled) through the suction filter 78, pressurized and discharged. The motor unit is electrically connected to a motor drive circuit electronically controlled by the ECU via a wire harness 79 that is taken out of the fuel tank.
The feed pump 5 is immersed in the fuel stored in the fuel storage chamber 16 of the sub tank 2. That is, the feed pump 5 is installed in the fuel storage chamber 16 of the sub tank 2 so as to be positioned below the liquid level of the fuel stored in the fuel storage chamber 16 of the sub tank 2 in the vehicle vertical direction.

A tank body 1 of the fuel tank is provided with a pump module including a sub tank 2, an ion exchange filter, a feed pump 5, a fuel pressure regulating valve 6, flanges 18 and 19, and the like. The flange 18 of this pump module is fitted into a fitting hole provided in the upper wall portion of the tank body 1 of the fuel tank, and other parts of the pump module (sub tank 2, ion exchange filter, feed pump 5, fuel adjustment). The pressure valve 6 and the flange 19 are installed in the tank body 1 of the fuel tank.
The flange 18 is coupled to the sub tank 2 via a plurality of support columns 80 extending in the vehicle vertical direction. The flange 18 is provided with a pipe joint 84 connected to a pipe joint 82 of the fuel supply pipe 81 via a fuel supply hose 83 and a pipe joint 86 of the fuel supply pipe 85. The fuel supply pipe 85 has a pipe joint 84 on the inner side of the tank body 1 (lower side in the vehicle vertical direction) than the flange 18, and on the outer side of the tank body 1 (upper side in the vehicle vertical direction) than the flange 18. Has a pipe joint 86. A fuel supply hose 87 connected to the inlet (inlet port) of the fuel filter 11 is connected to the pipe joint 86.

The flange 19 has a fuel supply pipe 81 coupled to the discharge part 20 of the feed pump 5. A fuel supply hose 83 is connected to the pipe joint 82 of the fuel supply pipe 81. Here, the fuel supply pipe 81, the fuel supply hose 83, the fuel supply pipe 85, and the fuel supply hose 87 constitute the supply pipe 21 of the fuel supply pipe. A branch portion 25 is provided in the middle of the fuel supply pipe 81. A branch channel 27 branched from the fuel supply channel in the fuel supply pipe 81 is opened in the channel wall surface of the branch part 25.
Further, the flange 18 has a fuel return pipe 93 having a pipe joint 92 to which a fuel return pipe 91 constituting a return pipe 74 of the fuel return pipe is connected, and fuel from the fuel return pipe 93 toward the fuel return chamber 17 of the sub tank 2. The fuel diversion plate (first fuel diversion means) 94 divides the flow at a predetermined diversion ratio into two or more fuel flows. The fuel distribution plate 94 has an annular base plate and a cylindrical outer wall portion 95 bent so that the outer peripheral portion of the base plate is bent upward in the figure. A plurality of fuel outlets 96 through which fuel is dropped into the fuel return chamber 17 of the sub tank 2 are formed in the outer wall portion 95.

The flange 19 is provided with a fuel pressure regulating valve 6. The fuel pressure regulating valve 6 is installed at the upstream end in the fuel flow direction of the fuel return pipe that returns the fuel to the fuel storage chamber of the fuel tank. The fuel pressure regulating valve 6 includes a valve case constituting a return pipe 75 of a fuel return pipe, a valve 7 for opening and closing a valve hole (branch flow path 27) formed in a fuel supply pipe 81 provided in the flange 19, and the valve. 7 is constituted by a coil spring 8 or the like that urges 7 in the valve closing operation direction. Further, the valve 7 of the fuel pressure regulating valve 6 opens overcoming the urging force (spring load) of the spring 8 when the pressure of the low-pressure fuel discharged from the feed pump 5 rises above a set value.
Further, the flange 19 has a flow of fuel from the fuel outlet 75a of the valve case constituting the return pipe 75 of the fuel return pipe to the fuel return chamber 17 of the sub tank 2 at a predetermined diversion ratio, and more than two fuels. A fuel diversion plate (second fuel diversion means) 97 for diverting the flow is provided. The fuel distribution plate 97 has an annular base plate formed integrally with the valve case of the fuel pressure regulating valve 6 and a cylindrical outer wall 98 bent so that the outer peripheral portion of the base plate is bent upward in the figure. ing. A plurality of fuel outlets 99 through which fuel is dropped into the fuel return chamber 17 of the sub tank 2 are formed in the outer wall 98.

When the remaining amount of fuel in the fuel storage chamber of the tank main body 1 is small in the tank wall forming the fuel storage chamber 16 of the sub tank 2 of the fuel tank (the fuel storage of the tank main body 1 is less than the upper opening of the sub tank 2). The fuel stored in the fuel storage chamber of the tank body 1 can be sucked into the fuel storage chamber 16 of the sub-tank 2 even when the liquid level of the fuel stored in the chamber is on the lower side in the vehicle vertical direction). A fuel inlet 101 is formed so as to be able to. The plurality of support columns 80 formed integrally with the sub tank 2 are attached to the coupling portion 102 of the flange 18 so as to be slidable in the axial direction. In this case, the position of the sub tank 2 in the vehicle vertical direction can be changed according to the level of the fuel stored in the fuel storage chamber of the tank body 1. A coil spring 103 for holding the distance between the upper opening of the sub tank 2 and the flange 18 at an appropriate position is mounted around the support column 80.
A fuel outlet 104 for the resin filling chamber is formed at the lower end of the housing 3 in the figure.

  As described above, in the fuel supply device for the internal combustion engine of the present embodiment, the leak port (or the pressure limiter 14) of any two or more fuel supply devices among the supply pump 12, the common rail 13, and the plurality of injectors 15 is used. ) From the return pipe 74 of the fuel return pipe for returning the surplus fuel to the fuel storage chamber 16 of the sub tank 2. Specifically, the fuel return pipe 93 that constitutes the return pipe 74 of the fuel return pipe is disposed below the fuel outlet 96 of the fuel diversion plate 94 to which the fuel is returned from the fuel return pipe 93 to which the fuel return pipe 93 is connected. A large number of ion exchange resin particles 4 having excellent ability to remove metal ions eluted in the fuel are filled in the fuel return chamber 17 of the sub tank 2.

Further, the valve 7 of the fuel pressure regulating valve 6 that opens and closes the branch passage 27 that branches from the middle of the fuel supply pipe 21, that is, from the middle of the fuel supply pipe 81, is inside the valve case that constitutes the return pipe 75 of the fuel return pipe. The ion exchange filter is disposed on the lower side in the vehicle vertical direction of the return pipe 75 of the fuel return pipe for returning the low pressure fuel flowing out from the valve case of the fuel pressure regulating valve 6 to the fuel storage chamber 16 of the sub tank 2.
Specifically, the fuel in the subtank 2 disposed on the lower side in the vehicle vertical direction with respect to the fuel outlet 99 of the fuel diversion plate 97 from which fuel is returned from the fuel outlet 75a of the valve case constituting the return pipe 75 of the fuel return pipe. By filling the return chamber 17 with a large number of ion-exchange resin particles 4 having excellent ability to remove metal ions eluted in the fuel, the same effect as in the first embodiment can be achieved.

In addition, the fuel tank of this embodiment, in particular, the flange 18 fitted in the fitting hole provided in the upper wall portion of the tank main body 1 is connected to the sub tank from the fuel return pipe 91 constituting the return pipe 74 of the fuel return pipe. There is provided a fuel diversion plate 94 that diverts the flow of fuel toward the two fuel return chambers 17 at a predetermined diversion ratio and into two or more fuel flows. As a result, the number of contacts between the fuel from the fuel return pipe 91 constituting the return pipe 74 toward the fuel return chamber 17 of the sub tank 2 and the ion exchange resin particles 4 filled in the fuel return chamber 17 of the sub tank 2 increases. The performance of the ion exchange resin particles 4, that is, the effect of removing metal ions can be improved.
Further, the fuel tank of this embodiment, particularly the flange 19 connected to the discharge part 20 of the feed pump 5 installed in the sub-tank 2 is connected to the sub-tank 2 from the valve case constituting the return pipe 75 of the fuel return pipe. A fuel diversion plate 97 is provided to divert the flow of fuel toward the fuel return chamber 17 at a predetermined diversion ratio and into two or more fuel flows. As a result, the number of contacts between the fuel from the valve case constituting the return pipe 75 toward the fuel return chamber 17 of the sub tank 2 and the ion exchange resin particles 4 filled in the fuel return chamber 17 of the sub tank 2 increases. The performance of the exchange resin particles 4, that is, the effect of removing metal ions can be improved.
In this embodiment, the two fuel diversion plates 94 and 97 are installed in the fuel tank. However, only one of the two fuel diversion plates 94 and 97 may be installed in the fuel tank. good.

[Modification]
In this embodiment, the ion exchange resin is made of particulate ion exchange resin, but the ion exchange resin may be made of powder ion exchange resin. Further, instead of the ion exchange resin particles 4, active particles such as chelate resin or activated carbon may be used. Further, the shape of the ion exchange resin particles 4 may be any of powder, fiber, or membrane in addition to the particle.
In this embodiment, the common rail 13 is installed as the fuel supply device, but the common rail 13 may not be provided. Further, a pressure reducing valve may be installed on the common rail 13 or the like instead of the pressure limiter 14. Further, a fuel injection nozzle may be used instead of the injector 15. Further, instead of the supply pump 12, a row type fuel injection pump or a distribution type fuel injection pump may be used.

1 is a configuration diagram showing a fuel supply device for an internal combustion engine (Example 1); FIG. It is sectional drawing which showed the injector (Example 1). It is sectional drawing which showed the fuel-injection nozzle of the injector (Example 1). (Example 2) which is the block diagram which showed the fuel supply apparatus of the internal combustion engine. (Example 3) which is the block diagram which showed the fuel supply apparatus of the internal combustion engine. (Example 4) which is the block diagram which showed the fuel supply apparatus of the internal combustion engine. (Example 4) which is sectional drawing which showed the ion exchange filter installed in the subtank. (A) is AA sectional drawing of FIG. 7, (b) is BB sectional drawing of FIG. 7 (Example 4).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tank body of fuel tank 2 Sub tank of fuel tank (pump module) 3 Housing (filter case) of ion exchange filter (metal ion removing means)
4 Ion exchange resin particles of ion exchange filter (metal ion removing means) 5 Electric feed pump (low pressure fuel pump, fuel supply equipment)
6 Fuel pressure regulating valve (fuel supply equipment)
11 Fuel filter (fuel supply equipment)
12 Supply pump (high pressure fuel pump, fuel supply equipment)
13 Common rail (fuel supply equipment)
14 Pressure limiter (fuel supply equipment)
15 Injector (fuel injection valve, fuel supply equipment)
16 Subtank fuel storage chamber 17 Subtank fuel return chamber 21 Supply piping (fuel supply piping)
22 Supply piping (fuel supply piping)
23 Supply piping (fuel supply piping)
24 Branch piping (fuel supply piping)
26 Branch pipe (fuel supply pipe)
71 Return piping (fuel return piping)
72 Return piping (fuel return piping)
73 Return piping (fuel return piping)
74 Return piping (fuel return piping, first return piping)
75 Return piping (fuel return piping, second return piping)
94 Fuel distribution plate (first fuel distribution means)
97 Fuel diversion plate (second fuel diversion means)

Claims (1)

In a fuel supply device that supplies fuel stored in a fuel tank to an internal combustion engine,
(A) a fuel supply device for supplying fuel from the fuel tank to the internal combustion engine;
(B) a fuel return pipe for returning fuel from the fuel supply device to the fuel tank;
(C) a metal ion removing means for removing metal components in the fuel,
The fuel supply device includes a low pressure fuel pump that pumps fuel from the fuel tank, a high pressure fuel pump that pressurizes fuel supplied from the low pressure fuel pump, and a fuel pressure regulating valve that regulates the pressure of fuel discharged from the low pressure fuel pump. And a fuel injection valve that injects fuel supplied from the high-pressure fuel pump into the internal combustion engine,
The fuel return pipe has a return pipe for returning the fuel flowing out from the fuel pressure regulating valve to the fuel tank,
The metal ion removing means is disposed in the fuel return pipe and has an ion exchange resin filled in the return pipe .

Images