JPH0634620Y2 - Fuel supply device for multi-cylinder internal combustion engine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply device for a fuel injection supply type multi-cylinder internal combustion engine, and more particularly to supporting a fuel injector provided for each cylinder and distributing fuel to these. It is related to the supply structure.

2. Description of the Related Art Generally, a fuel injection supply type multi-cylinder internal combustion engine has a fuel injector for each cylinder, and the fuel injector of each cylinder is attached to an intake manifold by a delivery pipe screwed to the intake manifold. The fuel is distributed and supplied from the delivery pipe, and a fuel injector support-fuel distribution structure of this type is shown in Japanese Utility Model Publication No. 52-127120.

As another one of the fuel injector support-fuel distribution structure, the fuel injector of each cylinder is screwed to an injector mounting seat portion provided in the intake manifold, and the fuel injection passage is provided from the fuel delivery passage provided in the intake manifold to the fuel injector. A fuel injector support-fuel distribution structure configured to distribute and distribute fuel has already been considered, which is shown, for example, in Japanese Patent Publication No. 56-24789.

Problems to be Solved by the Invention In any of the conventional fuel injector support-fuel distribution structures as described above, the fuel injector is exposed to the outside in any case, so that it is not affected by external heat. At high temperatures, the fuel inside may be heated and vapor may be generated.In addition, in the case of using a delivery pipe, there is a difficulty in the mounting strength of the fuel injector, and the fuel injector is not directly attached to the intake manifold. In this case, the intake manifold must be provided with a fuel delivery passage, which makes molding of the intake manifold difficult.

It is an object of the present invention to provide an improved fuel supply system for a multi-cylinder internal combustion engine that solves the above problems with a structure that is easy to manufacture and assemble.

Means for Solving the Problems According to the present invention, the above objects are combined with the main body portion of an elongated integral body extending along the cylinder row of a multi-cylinder internal combustion engine and the upper surface of the main body portion in an overlapping manner. A fuel delivery member having an integral lid portion; and a bare fuel injector individually provided for each cylinder, wherein the main body portion is spaced apart along the length direction from the upper surface. A lateral hole for loading each one of the bare fuel injectors and first and second longitudinal holes extending along the length thereof and communicating with all of the lateral holes, The fuel is supplied through the first vertical hole and the fuel is discharged through the second vertical hole, and the lower end of the horizontal hole hermetically seals the needle holder of the bare fuel injector. The upper end of the lateral hole Is hermetically closed by the lid portion, and the lid portion is provided with one of the electrical contacts for each of the bare fuel injectors facing the lateral holes. By inserting each one of the bare fuel injectors into each of them, and closing the lid portion on the upper surface of the main body portion, each of the bare fuel injectors has its needle holder in the lateral hole. In the state of being hermetically engaged in the opening at the lower end, it is fixed against movement in the left-right and up-down directions in the lateral hole, and at the same time, the other of the electrical contacts for each of the bare fuel injectors is the lid. A fuel supply system for a multi-cylinder internal combustion engine, characterized in that it is configured to engage said one of the body parts to achieve an electrical connection to each of said bare fuel injectors. It is.

The injector insert type fuel delivery member used in the fuel supply system for a multi-cylinder internal combustion engine according to the present invention as described above may be made of a synthetic resin having excellent fuel resistance, in other words, oil resistance.

Advantageous Effects and Advantages of the Invention According to the above-described configuration, the fuel injector is disposed inside the fuel delivery member and is entirely covered with the fuel delivery member, so that the fuel injector is less susceptible to thermal influence from the outside. For example, even if the temperature in the engine room of the vehicle becomes high, the temperature of the fuel in the fuel injector is prevented from becoming high, vapor is prevented from occurring, and the fuel injector has sufficient attachment strength to the fuel delivery member. Can be installed with. Further, as described above, the fuel delivery member is constituted by the main body of the slender one-piece body and the lid body of the one-piece body which is combined with the upper surface of the main body so that the fuel delivery member is provided at positions spaced along the length direction of the main body. A lateral hole is provided for loading each one of the bare fuel injectors, and first and second longitudinal holes extending along the length direction of the body portion and communicating with all of the lateral holes are formed. One of them serves as a fuel supply passage and the other serves as a fuel discharge passage.The needle holder of the bare fuel injector is airtightly engaged with the opening at the lower end of the lateral hole, and the lid body is overlaid on the main body. Together, the bare fuel injectors are fixedly fixed vertically and horizontally in each lateral hole, and at the same time, one of the electrical contacts provided on the lid part when the lid part is superposed on the body part and the bare fuel Joins with the other electrical contact on the injector Electrical connection to the bare fuel injector Te is by previously to be achieved, can get at the 且組 elevational simple structure and easy manufacture of the fuel supply apparatus according multi-cylinder internal combustion engine.

Embodiments Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 to 4 show an embodiment of a fuel supply system for a multi-cylinder internal combustion engine according to the present invention. In the figure, 10 shows a part of a cylinder head of an internal combustion engine, and an intake port 12 and a fuel injection port 14 are provided in the cylinder head. The cylinder head 10 has an intake manifold
16 is installed and the intake passage of the intake manifold
18 communicates with the intake port 12.

Further, in the figure, reference numeral 20 denotes a fuel delivery member, and the fuel delivery member is a body 22 made of synthetic resin having excellent oil resistance.
And a lid 24. The main body 22 and the lid body 24 are separably coupled to each other by a plurality of bolts 23 penetrating the lid body 24 and screwed to the main body 22. The main body 22 and the lid 24 are provided with a plurality of injector accommodating holes 26 spaced apart from each other corresponding to each cylinder. Each injector housing hole 26 is composed of a main body 22 and a lid body 24, and is opened only at a connecting portion 28 to the fuel injection port 14 formed in the main body 22 so as to project. That is, the injector housing hole 26 is opened at one end to the tip of the connecting portion 28 by the opening 30 and the other end is used as the injector inlet / outlet body 22.
The lid 24 and the lid 24 are separated and connected to each other to open and close.

A fuel supply passage 32 that connects the injector housing holes 26 to each other is provided in a straight line in the main body 22. The fuel supply passage 32 opens at one end of the main body 22 at one end, and this opening is internally threaded as a connection port 34 for a fuel supply pipe from a fuel pump (not shown). Also the main body
A fuel discharge passage 36 that connects the injector housing holes 26 to each other is provided in the line 22 in a straight line. Fuel discharge passage
36 is provided closer to the lid 24 than the fuel supply passage 32, and is open at one end to the other end of the main body 22, and this opening serves as a return fuel outlet 38. Return fuel outlet
A fuel inlet nipple 44 of a pressure regulator 42 attached to the main body 22 by a mounting bracket 40 is connected to 38 for communication, and a return fuel pipe for guiding return fuel to a fuel tank (not shown) is connected to the pressure regulator 42. 46 are connected in communication.

A bare fuel injector 50 is inserted into each of the injector housing holes 26. The fuel injector 50 is of the bottom feed type, as well shown in FIG. 4, and has a needle holder 54 having a nozzle 52 at the tip, and a needle valve 56 which is supported by the needle holder 54 and opens and closes the nozzle 52. , A solenoid body 60 that is connected to the needle holder 54 and that includes a solenoid coil 58 inside, a plunger 62 that is supported by the solenoid body 60 and that is connected to the needle valve 52, and the needle valve 56 together with the plunger 62 downward in the drawing. That is, the compression coil spring 64 that urges in the valve opening direction, the end cover 66 that is attached to the end portion of the solenoid body 60 to also hold the compression coil spring 64, and the outer periphery of the needle holder 54 and the solenoid body 60 are attached. And an outer shell 68 that has been set.

The fuel injector 50 includes a needle holder 54 and an O-ring 55.
Together with the end cover 66 inserted into the opening 30 of the connecting portion 28.
The annular protrusion 67 is inserted into the positioning ring 25 attached to the lid 24 so as to be positioned and supported by the fuel delivery member 20 in a double-sided manner, and the needle holder 54 having the injection port 52 is provided. The tip portion of the is projected to the outside from the connection portion 28.

A narrow annular fuel chamber 70 is formed between the outer wall of the outer shell 68 and the inner wall of the injector housing hole 26. The fuel chamber communicates with the fuel supply passage 32, and the gasoline Liquid fuel such as fuel is supplied. The fuel chamber 70 is a needle holder for the outer shell 68.
It communicates with a needle valve accommodating chamber 78 via an opening 72 provided on the 54 side, a fuel chamber 74 provided inside the outer shell 68, and a hole 76 provided in the needle holder 54.
Further, the fuel chamber 70 communicates with the fuel discharge passage 36 on the side farther from the needle holder 54, and further the outer shell 68.
The opening 80 provided in the and the hole 82 provided in the solenoid body 60 communicate with the arrangement portion of the outer peripheral cover 59 of the solenoid coil 58 to guide the fuel around the outer peripheral cover 59 to cool the solenoid coil 58. It has become. Fuel chamber
70 is an outer shell 68 and an injector housing hole on one side.
It is liquid-tight by a flat washer-like packing 84 sandwiched between it and the bottom wall of 26, and is liquid-tight on the other side by an O-ring 86 mounted on the outer circumference of the solenoid body 60.

A lead wire 90 for energizing the solenoid coil 58 of each fuel injector is embedded in the lid body 24 by insert molding. The lead wire 90 connects the fuel injectors 50 of the respective cylinders to each other in series with respect to its ground wire, but is separate for each fuel injector 50 of the respective cylinders with respect to the signal wire, and the fuel injectors 50 of the respective cylinders are connected.
Can be individually operated for fuel injection. The lead wire 90 as a ground wire and a signal wire of each cylinder is respectively
One end is electrically conductively connected to a female connector fitting 94 made of a spring provided in a connector hole 92 opened toward the injector housing hole 26, and the other end is connected to a collective connector 96 provided at one end of the cover 24. Conductive connection. The male connector 88 of the fuel injector 50 is directly inserted into the female connector fitting 94, and by this connection, each of the fuel injectors 50 is individually and selectively energized. There is.

The fuel delivery member 20 is formed by inserting a projecting connection portion 28 provided in the main body 22 into the inlet portion of the fuel injection port 14,
It is adapted to be fixed to the cylinder head 10 by a mounting bolt (not shown) which is inserted into a bolt through hole 27 penetrating the container 22 and the lid 24 and directly screwed to the cylinder head 10. The bolt through hole 27 is constituted by a metal insert member 29 so that the tightening compression force of the mounting bolt can be supported with sufficient strength.

As described above, all of the fuel injectors 50 of each cylinder are provided in the fuel delivery member 20 and
The fuel injector 50, which is covered by the fuel delivery member 20, particularly the synthetic resin fuel delivery member 20, makes the fuel injector 50 less susceptible to the thermal influence from the outside due to the heat insulation effect, and the fuel inside the fuel injector 50 becomes hot. Is avoided, and the generation of vapor is prevented. In particular,
In the illustrated embodiment, the connection 28 surrounds the needle holder 54 and the fuel injector 50 does not directly contact the cylinder head 10 at all, so the heat of the cylinder head 10 has a high thermal conductivity. Does not reach the fuel injector 50 by conduction, and this also prevents the fuel injector 50 from becoming hot.

5 to 7 show another embodiment of the fuel supply system for a multi-cylinder internal combustion engine according to the present invention. Incidentally, in FIGS. 5 to 7, the portions corresponding to FIGS. 1 to 4 are denoted by the same reference numerals as those given in FIGS. 1 to 4.

In this embodiment, in addition to the fuel supply passage 32 and the fuel discharge passage 36, another fuel passage 37 is provided in the main body 22 of the fuel delivery member 20 in parallel with the fuel discharge passage 36. The pressure regulator 42 communicates with the fuel discharge passage 36 to form a so-called return fuel passage 37.

In this embodiment, the surplus fuel given to the pressure regulator 42 from the fuel discharge passage 36 is returned as fuel from the pressure regulator 42 to the return fuel passage.
It flows to 37 and is returned to the fuel tank by a return fuel pipe (not shown) connected to a connection port 39 provided at the end of the return fuel passage 37.

In this embodiment, the fuel injector 50 is attached in the same manner as in the above-mentioned embodiment.

Therefore, it will be understood that in this embodiment, the same operation and effect as the above-mentioned embodiment can be obtained.

In the above, the present invention has been described in detail with reference to specific embodiments, but the present invention is not limited to this.
It will be apparent to those skilled in the art that various embodiments are possible within the scope of the invention.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing one embodiment of a fuel supply system for a multi-cylinder internal combustion engine according to the present invention, and FIG. 2 is a horizontal cross-sectional view of essential parts of the fuel supply system according to the present invention shown in FIG. 3, FIG. 3 is a plan view of an essential part of the fuel supply device according to the present invention shown in FIG. 2, FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 2, and FIG. 5 is according to the present invention. FIG. 6 is a vertical cross-sectional view showing another embodiment of the fuel supply device for a multi-cylinder internal combustion engine, FIG. 6 is a cross-sectional view showing the essential parts of the fuel supply device shown in FIG. 5, and FIG.
FIG. 7 is a horizontal cross-sectional view showing a main part of the fuel supply device according to the present invention shown in FIG. 10 …… Cylinder head, 12 …… Intake port, 14 …… Fuel injection port, 16 …… Intake manifold, 18 …… Intake passage, 20
…… Fuel delivery member, 22 …… Main body, 23 …… Bolt, 24…
… Lid, 25 …… Positioning ring, 26 …… Injector accommodating hole, 27 …… Bolt through hole, 28 …… Connection part, 29 …… Metal insert member, 30 …… Opening part, 32 …… Fuel supply passage , 34 ...
… Connection port, 36 …… Fuel discharge passage, 37 …… Fuel passage, 38 ……
Return fuel outlet, 39 …… Connection port, 40 …… Mounting bracket, 4
2 …… Pressure regulator, 44 …… Fuel inlet nipple, 46 …… Return fuel pipe, 50 …… Fuel injector, 52 …… Injection port, 54 …… Needle holder, 55 …… O-ring,
56 …… Needle valve, 58 …… Solenoid coil, 59 ……
Outer peripheral cover, 60 …… Solenoid body, 62 …… Plunger, 64 …… Compression coil spring, 66 …… End cover, 67 ……
Annular protrusion, 68 …… Outer shell, 70 …… Fuel chamber, 72…
… Opening, 74 …… Fuel chamber, 76 …… Hole, 78 …… Needle valve chamber, 80 …… Opening, 82 …… Hole, 84 …… Packing, 86 …… O-ring, 88 …… Male connector, 92 ...... Connector hole, 94 ...... Female connector

Claims (1)

[Scope of utility model registration request] 1. A fuel delivery member having a main body portion of an elongated integral body extending along a cylinder row of a multi-cylinder internal combustion engine, and a lid body portion of an integral body which overlaps and is combined with an upper surface of the main body portion. A laterally-directed fuel injector, which is provided individually for each cylinder, and which is spaced apart along the length of the main body portion so that each of the bare fuel injectors is loaded from the upper surface. And first and second vertical holes extending along the length direction and communicating with all of the lateral holes are provided, and fuel is supplied through the first vertical holes, and The fuel is discharged through the second vertical hole, and the lower end of the horizontal hole is an opening for hermetically receiving the needle holder of the bare fuel injector. The upper end is airtightly closed by the lid portion, One of the electrical contacts to each of the bare fuel injectors is provided in the body facing the lateral holes, and one of the bare fuel injectors is inserted into each of the lateral holes. , By closing the lid portion to the upper surface of the main body portion, each of the bare fuel injectors is in a state in which the needle holder thereof is airtightly engaged with the opening portion at the lower end of the lateral hole. While being fixed against movement in the left-right and up-down directions in the lateral hole, the other of the electrical contacts for each of the bare fuel injectors is engaged with the one provided on the lid portion and A fuel supply system for a multi-cylinder internal combustion engine, characterized in that an electrical connection is established for each of the bare fuel injectors.