JPH07247925A - Fuel injection device - Google Patents

Abstract

PURPOSE:To manufacture a fuel injection device inexpensively and to improve lubricating function by fuel for a throttle valve stem by making the fuel injection device in divided structure of an inlet pipe part and a cover part and jointing a chamber installation flange of the cover part on a cover part installation flange of the inlet pipe part. CONSTITUTION:A fuel injection device of an internal combustion engine is divided into an inlet pipe part 1 and a cover part 9, and a bottomed cylindrical chamber recessed part 7 a side wall 3 of which opens 3A toward a cover part installation flange 4 of one side from a bottom part 2 is formed on the inlet pipe part 1. Additionally, an inlet control passage 8 with a throttle valve 83 arranged in it one end of which opens to the side wall 3 of the chamber recessed part 7 and the other end of which opens to the outside air is formed on the inlet pipe part 1, and a plural number of inlet passages 5 one side of which opens to the bottom part 2 of the chamber recessed part 7 and the other side of which opens to an installation flange 6 on the side of an engine are formed. An air chamber 12 is partitioned by installing the cover part 9 by way of jointing an installation flange 11 on the installation flange 4 of the chamber recessed part 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention supplies air controlled by a throttle valve to an engine via an intake passage, and also supplies fuel controlled by a fuel injection valve toward air flowing in the intake passage. Fuel injection device.

[0002]

2. Description of the Related Art A conventional fuel injection device is shown in FIG. Referring to the drawings, the fuel injection device includes an intake pipe 60, an air chamber chamber 70, and an intake control pipe 80.
The air chamber 70 has a closed shape in which an opening 70B is formed in an upper side wall 70A in the drawing, and an intake control pipe 80 is connected to the opening 70B through a connecting pipe 71. An intake control passage 81 is bored through the intake control pipe 80, and the opening area of the intake control passage 81 is a shaft 82 rotatably supported by the intake control pipe 80.
It is controlled by the throttle valve 83 attached to the. On the other hand, a plurality of intake passages 60A are formed in the intake pipe 60, one end of the intake passage 60A is opened to the air chamber 70, and the other end is opened toward the engine E. In addition, J is a fuel injection valve which opens in each intake passage 60A of the intake pipe 60.

The throttle valve 83 is opened / closed by a driver, and the air flowing in the intake control passage 81 controlled by the throttle valve 83 flows into the air chamber 70 through the connecting pipe 71, and the air chamber The air in the chamber 70 is supplied to the engine E via the intake passages 60A of the intake pipe 60. On the other hand, from the fuel injection valve J, appropriately controlled fuel is injected into each intake passage 60A, whereby the fuel is mixed with the air flowing through the intake passage 60A, and thus the mixture containing the fuel and the air is mixed. Qi is supplied to the engine E.

[0004]

According to such a conventional fuel injection device, the air chamber 70 has a closed chamber shape, and the air chamber 70 is provided with openings in a plurality of directions (opening 70B). And the intake passage 60A is opened) to the air chamber 7 including the intake pipe 60.
It was difficult to make 0. For example, in the die casting method using a metal material (aluminum alloy, zinc alloy, etc.) and the injection molding method using a synthetic resin material (nylon, etc.), there is an undercut portion in the air chamber chamber 70, and therefore, molding cannot be performed. In addition, in the casting method using the sand mold, it is possible to manufacture, but it takes a lot of time to manufacture each piece, and there is a difficulty in mass production. Further, in the air chamber 70, There is a problem that it is difficult to smooth the inner wall surface and the air flow is obstructed.

On the other hand, since the intake control pipe 80 and the air chamber chamber 70 are connected by the connecting pipe 71, the distance between the injection hole of the fuel injection valve J and the shaft 82 supporting the throttle valve 83 is increased, This is not preferable because it has a problem that the lubrication action of the shaft 82 due to the fuel is reduced and increases the number of parts and the number of assembling steps.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is possible to inexpensively manufacture a fuel injection device including an intake passage, an air chamber chamber, an intake control pipe, and a shaft to which a throttle valve can be attached. The purpose is to improve lubrication by fuel.

[0007]

The object is to provide an intake control pipe having a throttle valve in the intake control passage, an air chamber chamber connected to the intake control passage downstream of the throttle valve, and one end of the air chamber. A plurality of intake passages that are open to the chamber and the other end of which is connected to the engine, and the air flowing in the intake control passage is controlled by a throttle valve to be supplied to the air chamber interior, In a fuel injection device that supplies fuel to an engine through a plurality of intake passages and injects fuel from a fuel injection valve into air flowing through the intake passages, the fuel injection device is divided into an intake pipe portion and a lid portion, The intake pipe section has a bottom, and a cylindrical chamber recess with a bottom whose side wall opens toward the lid mounting flange on one side of the bottom,
An intake control passage with one end opening to the side wall of the chamber recess and the other end opening to the atmosphere, and a plurality of intake passages having one side opening to the bottom of the chamber recess and the other side opening to the mounting flange on the engine side. And a bottom portion that closes the opening of the chamber recess and a chamber mounting flange that is arranged on the lid mounting flange of the chamber recess are provided in the lid portion, and on the lid mounting flange of the intake pipe portion. By joining the chamber mounting flange of the lid, the opening of the chamber recess of the intake pipe is closed by the lid to form the air chamber, and the throttle valve attached to the shaft in the intake control passage. And the fuel injection valve is arranged toward each intake passage.

[0008]

The fuel injection device is formed by being divided by the intake pipe portion and the lid portion, and the intake pipe portion is opened to one side from the bottom portion and to the other side from the bottom portion. It is formed by the intake passage and the intake control passage that opens upward from the side wall of the chamber recess, while the lid part is formed by the bottom part and the chamber mounting flange, so the intake pipe part and the lid part are undercut. It does not have a portion but can be molded by die casting or injection molding. Further, the assembling may be achieved by simply joining the chamber mounting flange of the lid to the lid mounting flange of the intake pipe. Thus, the fuel injection device can be provided at low cost. Furthermore, since the shaft to which the throttle valve can be attached is arranged in the intake control passage that opens directly to the chamber recess, the shaft can obtain good lubrication by the fuel injected from the fuel injection valve.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the fuel injection device according to the present invention will be described below with reference to FIGS. FIG. 1 is a vertical sectional view thereof,
FIG. 2 is a cross-sectional view taken along line XX of FIG. Reference numeral 1 denotes an intake pipe portion, a side wall 3 extends from the bottom portion 2 toward one side (left side in the drawing), an end portion thereof has an opening 3A, and a lid portion mounting flange 4 is formed on the outer periphery of the end portion. Further, a plurality of intake passages 5 are located on the other side of the bottom portion 2 (on the right side in the figure).
The other side end opens to the engine side mounting flange 6. The bottom portion 2 and the side wall 3 form a bottomed cylindrical chamber recess 7 having an opening 3A on one side.
An intake control passage 8 is formed in the side wall 3 so as to be substantially orthogonal to the side wall 3 and open upward. That is, one end of the intake passage 5 opens into the chamber recess 7 and the other end thereof opens into the mounting flange 6 on the engine side.
Has a lower end opening to the chamber recess 7 and an upper end opening to the atmosphere. In addition, in the present embodiment, four intake passages 5 are provided in the vertical direction, but the number and arrangement of the intake passages 5 are appropriately designed according to the installed engine. Further, one side of the intake passage 5 in this embodiment is further projected from the bottom portion 2 toward the chamber recess 7 side.

When the intake pipe portion 1 is formed by die casting or injection molding using a synthetic resin material, its outer shape is formed by a movable mold and a fixed mold, and the intake passage 5 and the chamber recess 7 are formed. In the figure, it is performed by a movable core that moves in the horizontal direction, and the intake control passage 8 is performed by a movable core that moves in the vertical direction. This is done because there is no undercut portion for the movable, fixed, mold and movable core based on the structure of the intake pipe section 1 described above.

Reference numeral 9 denotes a lid portion having the following structure. The lid 9 has a bottom 10 and is open on the other side, and a chamber mounting flange 11 joined to the lid mounting flange 4 of the chamber recess 7 is formed at the opening end. In this embodiment, the depth of the bottom portion 10 with respect to the lid mounting flange 4 is shallow, but it is appropriately selected.

When the lid 9 is molded by die casting or injection molding using a synthetic resin material, it is performed by a movable mold and a fixed mold. This is done because it is based on the structure of the lid 9 described above and does not have an undercut portion for the movable, fixed, and mold.

The intake pipe section 1 and the lid section 9 are assembled as follows. Place the chamber mounting flange 11 of the lid 9 on the lid mounting flange 4 of the intake pipe portion 1,
In this state, both flanges 4 and 11 are joined and integrated. This joining may be performed by any joining method such as screwing with screws, adhesion with an adhesive, flipping made of an elastic metal material, fitting with a hole and a locking projection. According to the above, the opening 3A of the chamber concave portion 7 of the intake pipe portion 1 is closed by the chamber mounting flange 11 of the lid portion 9, so that the chamber concave portion 7 is formed as a hermetically sealed air chamber chamber 12. Then, one side of each intake passage 5 opens into the air chamber 12, and the lower end of the intake control passage 8 also opens into the air chamber 12.

The shaft 82 and the throttle valve 83 are arranged in the intake control passage 8, and the fuel injection valve J is arranged in each intake passage 5. The shaft 82, the throttle valve 83, and the fuel injection valve J may be assembled either when the intake pipe section 1 is used alone or after they are assembled.

According to the fuel injection device assembled as described above, the amount of the air flowing in the intake control passage 8 is controlled by the throttle valve 83 to flow into the air chamber 12 and the inside of the air chamber 12 is changed. Air is divided by each intake passage 5 and supplied to the engine. On the other hand, the fuel injected from the fuel injection valve J is a controlled supply of fuel toward the air flowing in each intake passage 5. And thus satisfy the operation of the engine.

[0016]

According to the fuel injection device of the present invention as described above, the following special effects are obtained. For the lid and the intake pipe, when manufacturing the mold and core used during die casting and injection molding,
Since it does not have an undercut part, it is possible to manufacture them by die casting and injection molding, and it is possible to manufacture them extremely easily and efficiently, and greatly reduce the manufacturing cost. It was made. The lid portion and the intake pipe portion may be joined simply by stacking the flanges facing each other and joining them together, and furthermore, the joining can be performed very easily using a joining method which is generally used. Since the chamber mounting flange of the lid portion and the lid mounting flange of the intake pipe portion need only be joined once, the assembling cost can be made low, and the fuel injection device is inexpensive because of the reduction in the manufacturing cost. Can be provided to. Since the shaft is arranged directly in the intake control passage which is directly opened in the chamber recess without any connecting pipe, the shaft can be arranged in the vicinity of the air chamber. It was made, according to this,
When the fuel injected from the fuel injection valve returns to the air chamber due to the intake inertia, the shaft is lubricated efficiently by the fuel, and the rotatability of the shaft can be stably maintained for a long period of time. it can. In particular, it is suitable for a fuel injection device mounted on an outboard engine used at sea and used at sea when air containing salt flows down in the intake control passage.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a fuel injection device according to the present invention.

FIG. 2 is a cross-sectional view taken along line XX of FIG.

FIG. 3 is a vertical sectional view of a conventional fuel injection device.

[Explanation of symbols]

 1 Intake Pipe Part 2 Bottom Part 3 Side Wall 3A Opening 4 Lid Mounting Flange 5 Intake Path 6 Engine Side Mounting Flange 7 Chamber Recess 8 Intake Control Passage 9 Lid 11 Chamber Mounting Flange 12 Air Chamber Chamber 83 Throttle Valve J Fuel Injection Valve

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F02M 69/00 F02M 35/10 301 R 69/00 350 F F 350 P

Claims (1)

[Claims] 1. An intake control pipe having a throttle valve in the intake control passage, an air chamber connected to an intake control passage downstream of the throttle valve, one end of which opens to the air chamber and the other end of which opens. And a plurality of intake passages connected to the engine,
The air that flows in the intake control passage is controlled by the throttle valve to be supplied into the air chamber chamber, and the air in the air chamber chamber is supplied to the engine through a plurality of intake passages and the air flowing through the intake passage to the fuel injection valve. In a fuel injection device for injecting more fuel, the fuel injection device is divided into an intake pipe portion 1 and a lid portion 9, and the intake pipe portion 1 has a bottom portion 2 which is located on one side of the bottom portion 2. A bottomed cylindrical chamber recess 7 having a side wall 3 opening 3A toward the lid mounting flange 4
And an intake control passage 8 whose one end is open to the side wall 3 of the chamber recess 7 and the other end is open to the atmosphere, and one side is open to the bottom 2 of the chamber recess 7 and the other side is a mounting flange on the engine side. 6, a plurality of intake passages 5 that open to 6 are provided, and the lid 9 has a bottom 10 that closes the opening 3A of the chamber recess 7.
And a chamber mounting flange 11 arranged on the lid mounting flange 4 of the chamber recess 7, and the chamber mounting flange 11 of the lid 9 is joined to the lid mounting flange 4 of the intake pipe section 1. Thus, the opening 3A of the chamber recess 7 of the intake pipe portion 1 is closed by the lid portion 9 to form the air chamber chamber 12, and the throttle valve 83 attached to the shaft 82 is arranged in the intake control passage 8. At the same time, the fuel injection device is characterized in that a fuel injection valve J is arranged toward each intake passage 5.