JP5985190B2 - Fuel injection device for internal combustion engine - Google Patents

Description

  The present invention relates to a fuel injection device for an internal combustion engine in which fuel is pressurized and injected from an injector.

  In motorcycles (vehicles), a method of injecting fuel using an injector is widely used. In this fuel injection device for injecting fuel, a structure in which an intake pipe member constituting an intake pipe of an engine (corresponding to an internal combustion engine) is provided with a fuel pump for pressurizing fuel and an injector for injecting pressurized fuel is used. It is done. Many fuel pumps use a reciprocating pump unit to ensure a high fuel pressure, and a structure in which the pump unit is driven by a driving unit such as a motor unit is used. Recently, in order to suppress the influence of vapor, reduce costs, and make it compact, an integrated structure in which an injector, a fuel injection section, a reciprocating drive pump section, and a drive section are connected has become widespread. It's getting on.

  Many of these integrated fuel injection devices are configured such that, following the fuel injection portion provided in the intake pipe member as disclosed in Patent Document 1, the pump portion stands from one side in the radial direction of the intake pipe member. And a motor part (driving part) following a structure in which a motor part (corresponding to a driving part) is provided at the end of the standing pump part or an injector provided in an intake pipe member as disclosed in Patent Document 2. ) Is projected toward one side in the radial direction intersecting the intake pipe portion, and a pump portion is provided at the projecting end portion of the motor portion.

Japanese Utility Model Publication No. 4-54974 JP 2005-105987 A

By the way, the engine of a motorcycle is housed in a limited space (engine room) surrounded by a fuel tank, a seat, a frame and the like. Engine accessories are also housed in this limited space. In other words, the fuel injection device attached to the engine is also housed in this limited space together with the engine accessories.
For this reason, the fuel injection device is designed around the intake pipe member as much as possible, specifically the diameter of the intake pipe member, so that it does not interfere with surrounding equipment and objects, and does not affect the surrounding equipment. A compact design that suppresses overhanging outward is required.

  However, even if the fuel injection device of Patent Document 1 is compact, the entire fuel pump, that is, the pump portion and the motor portion constituting the fuel pump are biased and arranged on one side in the radial direction of the intake pipe member. Overhangs from one side in the radial direction of the intake pipe member. For this reason, this fuel injection device often interferes with surrounding equipment or objects or affects surrounding equipment, and tends to be difficult to mount on a motorcycle. In particular, a fuel injection device that uses an injector for the fuel injection portion and integrates the injector, the pump portion, and the drive portion further increases the overhang, making it more difficult to mount the fuel injection device on a motorcycle.

Since the fuel injection device of Patent Document 2 also has a pump part and a motor part of the fuel pump which are considerably biased and protrude toward one radial side of the intake pipe member, the fuel injection apparatus is mounted on a motorcycle as in Patent Document 1. At the same time, it often interferes with surrounding equipment and objects, and affects surrounding equipment, and is difficult to mount on a motorcycle.
SUMMARY OF THE INVENTION An object of the present invention is to provide a fuel injection device for an internal combustion engine that is excellent in mountability in a vehicle and is prevented from protruding from the intake pipe member to the surroundings (radially outward).

  According to a first aspect of the present invention, in order to achieve the above object, the fuel injection device includes a reciprocating drive type pump unit that pressurizes the fuel at the outer peripheral portion of the intake pipe member, and the pump portion in the circumferential direction of the outer peripheral portion. A fuel pump that is arranged along the reciprocating drive direction and a drive unit that drives the pump is arranged along the circumferential direction of the intake pipe member following the pump unit, and a fuel pump provided in the fuel pump And an injector for injecting the fuel from the intake pipe member into the intake pipe member.

  According to this configuration, the pump unit and the drive unit of the fuel injection device are arranged along the circumferential direction of the intake pipe member. In other words, the fuel injection device has a layout in which each part including the injector does not protrude as far as possible (outside) of the intake pipe member, that is, does not protrude to the periphery, and is compactly assembled on the outer periphery of the intake pipe member. Stick. The fuel injection device can be easily mounted on a vehicle by preventing the interference with the devices and objects around the intake pipe member and affecting the devices and objects by the compact layout with the overhang suppressed. This is effective for a vehicle such as a motorcycle that requires arrangement in a considerably limited space (engine room).

  In addition to the above object, the invention of claim 2 further includes a reciprocating pump unit so that a fuel injection device using a plunger type pump unit can be prevented from protruding from the intake pipe member to the surroundings. The plunger-type pump part that is configured is arranged on the outer peripheral part of the intake pipe member along the reciprocating drive direction in a direction that intersects the axial center direction of the intake pipe member, and the motor part that constitutes the drive part is a plunger-type pump From the end of the intake pipe member, it is arranged in a substantially L shape along the circumferential direction of the outer peripheral portion of the intake pipe member.

The invention of claim 3, further added to the above-mentioned object, so that the fuel injection device is less likely deflection vibration or impact transmitted from the intake pipe member, the driving unit and the pump unit of the reciprocating type is on the outer peripheral portion of each intake pipe member it was decided to place.
According to the invention of claim 4, the pump part and the drive part are arranged on a circular locus centering on the axis of the intake pipe member so that each part of the fuel injection device is not easily shaken. .

According to the invention of claim 5, in addition to the above object, the plunger-type pump unit has a pressure regulator that keeps the discharged fuel at a predetermined pressure so that fuel of an appropriate pressure is discharged from the injector.
In the invention of claim 6, in addition to the above object, the plunger type pump part has a diaphragm type pump part that assists the suction of the plunger type pump part so that the suction function of the plunger type pump part is enhanced.

According to the first aspect of the invention, the fuel injection device is compactly assembled to the outer peripheral portion of the intake pipe member with a layout in which each part including the injector is prevented from projecting to the surroundings. Interference with equipment and objects, and influence on the equipment and objects can be avoided, making it easier to install in vehicles.
Therefore, it is possible to provide a fuel injection device that is excellent in vehicle mountability and is prevented from protruding from the intake pipe member to the periphery (radially outward). In particular, this fuel injection device is effective for a vehicle such as a motorcycle, which is disposed in a considerably limited space (engine room).

  According to the second aspect of the present invention, even in the fuel injection device using the plunger-type pump part that is difficult to suppress overhanging, it is possible to suppress overhanging (outward in the radial direction) from the intake pipe member. As a result, the fuel injection device can be mounted on a vehicle in a manner similar to the above, in which each part including the injector is prevented from interfering with or affecting the devices and objects around the intake pipe member. It becomes easy to do.

According to the invention of claim 3, the fuel injection device can not only suppress the overhang of each part, but can also suppress the vibration of the pump part and the motor part centered on the intake pipe member, and also obtain high vibration resistance. be able to.
According to the invention of claim 4, the fuel injection device can effectively improve the vibration resistance.

According to the fifth aspect of the present invention, even if the pressure regulator that discharges the fuel of the appropriate pressure from the injector is provided, the vehicle mountability is hardly changed.
According to the sixth aspect of the present invention, even if the diaphragm type pump part that assists the suction of the plunger type pump part is provided, the vehicle mountability is hardly changed.

The side view which shows the fuel-injection apparatus which concerns on one Embodiment of this invention with the motorcycle which mounts the apparatus. The perspective view which similarly shows the external appearance and internal structure of a fuel-injection apparatus. The disassembled perspective view which shows the state which removed the main part of the fuel-injection apparatus from the intake pipe member similarly. Sectional drawing seen from the AA line in FIG. Sectional drawing which shows the plunger type pump part, diaphragm type pump part, pressure regulator, and motor part (part) along the BB line in FIG.

Hereinafter, the present invention will be described based on an embodiment shown in FIGS.
FIG. 1 is a side view (schematic) of a vehicle, for example, a motorcycle, on which a fuel injection device to which the present invention is applied is installed. An arrow F in FIG. 1 indicates the front direction of the motorcycle, and an arrow R indicates the rear direction of the motorcycle.

  First, the motorcycle shown in FIG. 1 will be described. The motorcycle has a main frame member that extends in the front-rear direction, for example, a main tube member 1 (only a part is shown). A front wheel 5 is suspended from a front end of the main tube member 1 via a front fork 3, and a rear wheel 9 is suspended from a rear end of the main tube member 1 via a swing arm member 7.

  A fuel tank 11 and a seat 12 are installed on the main tube member 1 in order from the front side. Incidentally, an acceleration / deceleration system (not shown) such as a brake pedal and a throttle grip is provided on one side (right side) sandwiching the main tube member 1, and a speed change system (not shown) such as a clutch lever and shift pedal is provided on the opposite side (left side). Not).

  In a space (engine room) surrounded by the down tube member 1a extending downward from the main tube member 1 and the fuel tank 11, an internal combustion engine, for example, a reciprocating engine 13 in which a piston 13a is reciprocally mounted is installed. is there. A short pipe member 15 (corresponding to the intake pipe member of the present application) and a throttle valve device 17 are connected to the intake side of the engine 13 in order, and an intake side port (not shown) of the engine 13 and an air cleaner (not shown) are connected. An intake pipe that communicates with each other is formed.

The short pipe member 15 is provided with each device constituting the fuel injection device 21, specifically, an electronically controlled injector 19, and a fuel pump 20 for supplying fuel to the injector 19. The injector 19, the fuel pump 20, Constitutes an integrated fuel injection device 21. The fuel injection device 21 is installed using a limited space near the engine 13.
The perspective view of FIG. 2 shows the entire fuel injection device 21 and the internal structure (dotted line portion). The exploded perspective view of FIG. 3 shows the main body of the fuel injection device 21 for a motorcycle. The state removed from the short pipe member 15 is shown, and the cross-sectional views of FIGS. 4 and 5 show cross sections of the fuel injection device 21 (cross sections taken along lines AA and BB in FIG. 2). Has been.

The fuel injection device 21 will be described with reference to FIGS. 2 to 5. The fuel pump 20 includes a reciprocating pump unit 25 and a drive unit 27 that drives the pump unit 25 in series. .
Among these, the pump part 25 is comprised with the plunger-type pump part 35 which accommodated various pump components in the axial direction in the cylindrical pump main body 33, as FIG.2 and FIG.5 shows. Incidentally, the pump body 33 is composed of a main body portion 33a and a lid portion 33b that are divided into two in the axial direction.

  The plunger-type pump unit 35 has a diaphragm-type pump unit 49 on one end side across the pump parts of the pump unit 35 and a pressure regulator 61 on the other end side, and is configured in a cylindrical shape (see FIG. 2). 5). As shown in FIG. 5, the plunger-type pump unit 35 includes a cylindrical sleeve 37 incorporated along the axial direction of the pump body 33 with one end portion as a suction side and the other end portion as a discharge side. A cylindrical plunger 39 accommodated in the sleeve 37 so as to be able to reciprocate, a suction valve 41 assembled in the lumen of the plunger 39, and a discharge valve 43 assembled on the discharge side of the sleeve 37. . That is, when the plunger 39 is driven to reciprocate, the plunger-type pump unit 35 guides the fuel (suction fuel) in the plunger 39 through the suction valve 41 to the pressurizing chamber 45 formed at the sleeve end. Pressurized in the chamber 45 and the pressurized fuel is discharged from the discharge valve 43. The injector 19 is assembled to the pump main body 33 of the plunger pump unit 35 and constitutes the main body of the fuel injection device 21 together with the drive unit 27.

  Incidentally, as shown in FIG. 5, the diaphragm-type pump unit 49 includes a diaphragm chamber 51 formed on the suction side of the sleeve 37, a diaphragm 53 provided so as to close the diaphragm chamber 51, and a central portion of the diaphragm 53 at the end of the plunger 39. And a suction valve 57 communicating with the diaphragm chamber 51 through a passage 57a. Thus, when the plunger 39 reciprocates, the diaphragm 51 oscillates, and fuel is sucked from the suction valve 57 and guided into the plunger 39 by the pump operation in the diaphragm chamber 51 caused by the amplitude. The diaphragm type pump part 49 helps the insufficient suction function of the plunger type pump part 35. The diaphragm chamber 51 also communicates with a return fuel discharge valve 59 through a passage 59a.

  As shown in FIG. 5, the pressure regulator 61 has a structure in which the outlet of the discharge chamber 63 formed on the outlet side of the discharge valve 43 is closed with a diaphragm 67 with a relief valve 65, and the diaphragm 67 is held by a spring member 69. Specifically, according to the biasing force of the spring member 69, the fuel discharged from the discharge chamber 63 communicates with the discharge port 63, that is, the diaphragm chamber 64 defined by the diaphragm 67, that is, the chamber 62 on the biasing side of the diaphragm chamber 64. At the stage toward the head, the pressure is adjusted to a predetermined pressure. In addition, when the fuel discharged from the discharge chamber 63 has excessive fuel pressure, the fuel of the same pressure is supplied to the opposite chamber partitioned by the diaphragm 67, that is, the spring chamber 71 containing the spring member 69 through the relief valve 65. It has a structure to escape. The pressure regulation chamber 63 communicates with the injector 19 through a passage 19a and a connection port 33c formed in the pump main body 33 described later (a portion where the base portion of the injector 19 is fitted), and fuel of an appropriate pressure is supplied. It is supplied to the injector 19.

  As shown in FIG. 2, for example, a cylindrical motor unit 27 a in which a DC motor 75 is housed in a cylindrical motor case 73 is used for the drive unit 27. A cam mechanism 77 (conversion mechanism) that converts rotational motion into reciprocating motion is built in the end of the motor case 73 where the output shaft of the DC motor 75 is disposed. Here, the cam mechanism 77 is configured by, for example, assembling an eccentric cam 79 on the output shaft of the DC motor portion 75 and fitting a frame-shaped cam receiving member 81 to the eccentric cam 79. Is converted to reciprocating motion. The output portion of the cam receiving member 81 is disposed on the end portion of the motor case 73, here on the side portion perpendicular to the axial direction of the motor portion 27a.

The pump unit 25 and the drive unit 27 are assembled on the outer periphery of the short tube member 15 so as not to protrude as far as possible to the outside in the radial direction of the surrounding short tube member 15.
In this device, as shown in FIGS. 2 to 4, a structure in which the pump portion 25 and the drive portion 27 are arranged along the circumferential direction of the outer peripheral portion of the short tube member 15 is used.

  Specifically, as shown in FIGS. 2 to 4, the plunger-type pump unit 35 constituting the pump unit 25 intersects the axial direction of the short tube member 15 at the upper part of the outer peripheral portion of the short tube member 15. By assembling horizontally, the short pipe member 15 is arranged along the circumferential direction. In particular, the plunger-type pump unit 35 has a reciprocating drive direction of the pump unit 35 (a direction in which the plunger 39 is reciprocated), here an intermediate part in the axial direction of the plunger-type pump part 35 and the axial direction of the short tube member 15. Are crossed, for example, orthogonally crossed, along the outer peripheral portion of the short tube member 15.

As shown in FIGS. 2 to 5, the motor unit 27 a constituting the drive unit 27 is arranged in an approximately L shape from the end of the plunger pump unit 35 along the circumferential direction of the outer peripheral portion of the short tube member 15. In this manner, following the plunger type pump part 35, the short pipe member 15 is arranged along the circumferential direction of the outer peripheral part. Specifically, in order to transmit the driving force from the motor part 27 a to the plunger 39, the motor part 27 a is connected to the side of the motor case 73 having the output part of the cam mechanism 75 and the pump body 33 having the input part of the plunger 39. It is connected to the end of the. This motor part 27a is arranged along the downward direction, and the entire motor part 27a is arranged along the outer peripheral part of the short tube member 25 in a vertical arrangement different from the plunger pump part 35.
Note that both the plunger-type pump unit 35 and the motor unit 27 a are closest to the outer peripheral portion of the short tube member 15.

  Incidentally, a suction connection port body 29 and a return connection port body 31 project from the end portion (lid portion 33b) of the plunger pump portion 35 on the side opposite to the motor portion 27a of the plunger pump portion 35. Has been. The suction connection port body 29 communicates with the suction valve 57, and the return connection port body 31 communicates with the discharge valve 59. Among them, the suction connection port body 29 includes a fuel supply hose member 85 (only a part of which is shown by a two-dot chain line) extending from the lower portion of the fuel tank 11 and a stopper 86 such as a hose band (two in FIG. 4). The fuel in the fuel tank 11 can be led to the suction connection port body 29. The return connection port 31 is connected to a return hose member 87 (a part of which is shown by a two-dot chain line, only a part thereof) extending from the fuel tank 11 by a stopper 88 such as a hose band. The fuel, that is, excess fuel from the diaphragm pump unit 49 that is not sucked from the plunger pump unit 35 is collected into the fuel tank 11. Incidentally, the fuel escaping from the relief valve 65 also goes to the return connection port 31.

  The fuel injection device 21 is fixed to the short tube member 15 with a structure that stops the injector 19, the plunger pump unit 35, and the motor unit 27a. Specifically, as shown in FIGS. 2 to 4, the injector 19 is fitted with a connection port body 33 c formed at the intermediate portion of the plunger-type pump portion 35, and the injection portion 19 a at the tip portion is connected to the short tube member 15. It is supported by being fitted to a support opening 15a (only a part of which is shown in FIGS. The plunger type pump part 35 is supported by connecting the middle part opposite to the injector 19, and the motor part 27 a is supported by suppressing the swing about the axis of the plunger type pump part 35 as a fulcrum. Yes. For example, the plunger-type pump part 35 has a plate-like bracket part 95 protruding from the outer peripheral part of the intermediate part of the pump main body 33, a base-like mounting seat 98 provided on the outer peripheral part of the short tube member 15, and the bolt member 99. The bracket portion 95 is supported by a structure that is fastened to the mounting seat 98 by screwing. In addition, the motor portion 27a is provided with a pin portion 101 in parallel on the side portion of the motor portion 27a adjacent to the short tube member 15, for example, and a pin receiving seat 103 that receives the pin portion 101 on the outer peripheral portion of the short tube member 15. The motor unit 27a is supported by the short tube member 15 with a motor steadying structure in which the pin unit 101 is inserted into the pin hole 103a formed in the pin receiving seat 103 when the plunger pump unit 35 is attached. (FIG. 3).

  In the fuel injection device 21 configured as described above, since the plunger type pump unit 35 and the motor unit 27a are laid out along the circumferential direction of the short tube member 15, each part including the injector 19 of the fuel injection device 21 includes In addition, it does not protrude from the periphery (outside) of the short tube member 15 only in a specific direction. That is, as shown in FIGS. 2 and 4, the entire fuel injection device 21 is compactly assembled to the outer peripheral portion of the short tube member 15 with a layout that suppresses overhanging as much as possible.

  Therefore, even if the fuel injection device 21 is required to be installed in a fairly limited space near the engine 13, the fuel injection device 21 is installed without interfering with or affecting the surrounding devices and objects. Can be easily dressed. In particular, when the intermediate part of the plunger type pump part 35 is arranged on the short pipe member 15, the overhang is considerably suppressed. As a result, the fuel injection device 21 can be easily mounted in the engine room and has a considerably excellent vehicle mounting property. This is effective for a vehicle such as a motorcycle in which the fuel injection device 21 is required to be arranged in a fairly limited small space near the engine 13.

  In particular, even in the fuel injection device 21 using the plunger-type pump unit 35 that is difficult to suppress overhang, the reciprocating drive direction of the pump unit 35 is linearly along the circumferential direction of the short tube member 15, and this tangent line. By arranging the motor portion 27a in a substantially L shape along the circumferential direction of the short tube member 15 from the end portion of the plunger-type pump portion 35 arranged in the direction, devices and objects around the short tube member 15 can be easily obtained. And it can be easily mounted on a vehicle such as a motorcycle.

  Moreover, with such an L-shaped fuel injection device 21, the vehicle mountability is such that the pressure regulator 61 that discharges fuel at an appropriate pressure and the diaphragm pump portion 37 that assists the suction of the plunger pump portion 35 are provided. Almost unchanged.

  In addition, the plunger-type pump unit 35 and the motor unit 27a are arranged closest to the outer periphery of the short tube member 15, respectively, and the rotational moment generated in the plunger-type pump unit 35 and the motor unit 27a with the short tube member 15 as the center. Therefore, even if the fuel injection device 21 as a whole is subjected to engine vibration or traveling vibration transmitted from the short tube member 15, it is difficult to shake, and the vibration resistance of the fuel injection device 21 itself is considerably improved. In particular, as shown in FIG. 4, when the plunger-type pump unit 35 and the motor unit 27 a are arranged on a circular locus that is closest to the outer peripheral portion of the short tube member 15 around the axis of the short tube member 15. The vibration of each part of the fuel injection device 21 around the short pipe member 15 is effectively suppressed, and the vibration resistance is effectively enhanced.

  Note that the present invention is not limited to one embodiment, and various modifications may be made without departing from the spirit of the present invention. For example, in one embodiment, an example in which a fuel injection device is provided in a short pipe member (an intake pipe member that constitutes an intake pipe) separate from the throttle valve apparatus has been described. You may provide a pump part, a drive part, and an injector in the body (intake pipe member which comprises an intake pipe).

15 Short pipe member (intake pipe member)
DESCRIPTION OF SYMBOLS 19 Injector 20 Fuel pump 21 Fuel injection apparatus 27a Motor part (drive part)
35 Plunger type pump part (pump part)
37 Diaphragm type pump part 61 Pressure regulator

Claims (6)

An intake pipe member constituting the intake pipe of the internal combustion engine;
A reciprocating pump unit that pressurizes fuel; and a drive unit that drives the pump unit. The pump unit is disposed on an outer peripheral part of the intake pipe member in a circumferential direction of the outer peripheral part. A fuel pump configured to be arranged along the reciprocating drive direction of, and arranged along the circumferential direction of the intake pipe member following the pump unit, and
A fuel injection device for an internal combustion engine, comprising: an injector provided in the fuel pump and injecting fuel from the fuel pump into the intake pipe member. The reciprocating pump unit is configured to have a plunger pump unit,
The plunger-type pump part is disposed on the outer peripheral part of the intake pipe member along a reciprocating drive direction in a direction intersecting with an axial direction of the intake pipe member,
The drive unit is configured to have a motor unit,
2. The fuel injection of the internal combustion engine according to claim 1, wherein the motor unit is disposed in an approximately L shape from an end of the plunger pump along a circumferential direction of an outer peripheral part of the intake pipe member. apparatus. The reciprocating pump portion and the drive portion of the driven, the fuel injection system for an internal combustion engine according to claim 1 or claim 2, characterized in that you have placed on the outer periphery of each of the intake pipe member.   4. The reciprocating pump unit and the driving unit are arranged on a circular locus centering on an axis of the intake pipe member. A fuel injection device for an internal combustion engine as described.   The fuel injection device for an internal combustion engine according to any one of claims 2 to 4, wherein the plunger type pump unit includes a pressure regulator that keeps the discharged fuel at a predetermined pressure.   The fuel injection device for an internal combustion engine according to any one of claims 2 to 5, wherein the plunger type pump unit includes a diaphragm type pump unit that assists suction of the plunger type pump unit.

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