JP2000249025A - Mounting structure of fuel injection device - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention aims at mounting an injector to a cylinder head by engaging a circlip in an annular groove formed in a cylinder head, and eliminating conventional holding clamps, bolts, and mounting members. It is an object of the present invention to reduce the number of parts, to reduce the cost, to be economically advantageous, and to contribute to weight reduction. For this purpose, a fuel injection device is supported in which one end of an injector is supported by a cylinder head of an internal combustion engine so as to be directed to a combustion chamber, and the other end is supported by fitting the delivery pipe and fixing the delivery pipe. In the structure, a support portion supporting one end side of the injector is provided on the cylinder head, an annular groove is provided on an inner peripheral surface provided on the support portion, and a circlip which engages in the annular groove and fixes the injector is provided. I have.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for a fuel injection device, and more particularly to a fuel injection device, in which a circlip is engaged in an annular groove formed in a cylinder head to mount an injector on the cylinder head. ,
The mounting member can be abolished, the number of parts can be reduced, the cost can be reduced, the cost can be reduced, it is economically advantageous, and it can contribute to the weight reduction, which is practically advantageous, and furthermore, the conventional holding clamp With the abolition of bolts and mounting members,
The present invention relates to a mounting structure of a fuel injection device which can simplify a cylinder head and can increase a layout width of a water passage, an oil passage, and the like.

[0002]

2. Description of the Related Art An injector injects and supplies fuel in a fuel tank to a combustion chamber formed by a cylinder head, a cylinder block, and a piston of an internal combustion engine.

The injector is provided with a delivery pipe for supplying fuel to each of a plurality of cylinders of the internal combustion engine.

When the injector is mounted on a cylinder head of an internal combustion engine, one end of the injector is supported by the cylinder head, and a delivery pipe is fitted to the other end of the injector, and the delivery pipe is fixed. The other end of the injector is supported.

The mounting structure of the fuel injection device is disclosed in JP-A-6-58230, JP-A-6-235366, JP-A-8-144887, and JP-A-8-31.
JP-A-2503, JP-A-8-338332, JP-A-8-338346, JP-A-9-144629 and JP-B-7-5248.

[0006]

In the conventional fuel injection device mounting structure, various measures have been adopted to mount the injector.

That is, in the fuel pressure control device disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 6-58230, a leaf spring having an annular ring engaged with a flange portion of a fuel pressure regulating valve and this leaf spring are provided. A locking member is required,
There is a disadvantage that the number of parts increases and the configuration becomes complicated.

Further, in the injector mounting structure disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 6-235366,
A holding member that holds down the flange of the injector is provided, and members such as a holding block, a holding cover, a holding clamp, and mounting screws are required.
There is a disadvantage that the number of parts increases and the configuration becomes complicated.

Further, in the fuel injection device disclosed in the above-mentioned Japanese Patent Application Laid-Open No. H8-144887, a mounting plate is inserted into a mounting groove portion of the fuel injection valve and a slit portion of the fuel distribution supply portion, and the fuel supply valve is connected. It is fixed to the fuel distribution and supply unit, and it is necessary to form mounting grooves and slits, and it is necessary to provide a mounting plate, increasing the number of parts,
There is a disadvantage that the configuration is complicated.

[0010] Furthermore, the above-mentioned Japanese Patent Application Laid-Open No. 8-31250 is disclosed.
In the mounting structure of the injector for a direct injection type internal combustion engine disclosed in Japanese Patent Publication No. 3 (1993), pressing means made of an elastic material for pressing and positioning the injector toward the engine body is provided. Bolts and the like for fixing the means are required, so that the number of parts increases and the configuration becomes complicated.

In the fuel supply pipe of the engine disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 8-338332, a base pipe and a branch pipe for mounting an injector are provided, and the injector is fixed to the branch pipe by a positioning plate. No positional relationship with the cylinder head attachment site is disclosed.

[0012] The injector mounting structure disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 8-338346 has an engaging portion for holding the injector so that it cannot rotate relatively.
It is necessary to provide a non-cylindrical portion between the injector body and the delivery pipe, which is disadvantageous in that it is difficult to manufacture and increases the cost.

In the injector mounting structure for an engine disclosed in Japanese Patent Application Laid-Open No. Hei 9-144629, the injector is disposed between the cams for operating the intake and exhaust valves, and the mounting position of the injector on the cylinder head is determined by the cam. There is an inconvenience that it is determined by the shaft and it is difficult to change the mounting position of the injector.

In the fuel injection device for an internal combustion engine disclosed in Japanese Utility Model Publication No. 7-5248, a heat dissipation window for exposing a part of the housing is formed in the connector mold, and the housing is required. At the same time, it is necessary to process the heat dissipation window, which increases the number of parts and complicates the configuration.

[0015]

Accordingly, in order to eliminate the above-mentioned disadvantages, the present invention supports an injector on a cylinder head of an internal combustion engine so that one end of the injector is directed toward a combustion chamber, and the other end is connected to a delivery pipe. In the mounting structure of the fuel injection device, which is fitted and fixed by fixing the delivery pipe, a support portion for supporting one end of the injector is provided on the cylinder head, and an annular groove is provided on an inner peripheral surface provided on the support portion. And a circlip engaging with the annular groove and fixing the injector is provided.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION
When mounting the injector to the cylinder head, insert one end of the injector into the support, engage the circlip in the annular groove, attach the delivery pipe to the other end of the injector, and use the conventional clamps and bolts. The mounting member is eliminated, the number of parts is reduced, the cost is reduced, and the cylinder head is simplified.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

1 to 4 show an embodiment of the present invention. In FIG. 2, reference numeral 2 denotes a direct injection type internal combustion engine.

The internal combustion engine 2 has a cylinder block (not shown), a cylinder head 4 mounted on the upper surface of the cylinder block, and a cylinder head cover 6 mounted on the upper surface of the cylinder head 4.

In the internal combustion engine 2, a combustion chamber 8 is formed by a cylinder (not shown) of a cylinder block, an upper surface of a piston reciprocating in the cylinder, and a lower surface of the cylinder head 4.

An intake port 10 and an exhaust port 12 communicating with the combustion chamber 8 are formed in the cylinder head 4, respectively. An intake valve 14 is disposed at a downstream end of the intake port 10, and an upstream of the exhaust port 12 is provided. Exhaust valve 16 at end
Is arranged.

Further, an injector 18 directed to the combustion chamber 8 is provided. The injector 18 is supported by the cylinder head 4 of the internal combustion engine 2 with one end directed toward the combustion chamber, and the other end is fitted to the delivery pipe 20 and fixed by fixing the delivery pipe 20. I have.

At this time, a support portion 22 for supporting one end of the injector 18 is provided on the cylinder head 4, and an annular groove 24 is provided on an inner peripheral surface 22 c of the support portion 22. Then, a circlip 26 for fixing the injector 18 is provided.

More specifically, the support portion 22 includes an insertion hole 22a into which one end of the injector 18 is inserted, a bottom surface 22b around the insertion hole 22a, and a bottom surface 22b.
And a peripheral inner peripheral surface 22c.

A circlip 26 made of a wire is inserted into an annular groove 24 formed in the inner peripheral surface 22c of the support portion 22.
To fix the injector 18.

When the injector 18 is fixed to the cylinder head 4, the flange-shaped step 18 a formed at one end of the injector 18 is made to correspond to the bottom surface 22 b around the insertion hole 22 a of the support 22. One end of the injector 18 is inserted into an insertion hole 22a formed at the center of the bottom portion 22b of the support portion 22, and an elastic compressible gasket 28 is interposed between the bottom portion 22b and one end of the injector 18. .

At this time, since the gasket 28 is compressible, the gasket 28 is compressed by the step 18a on one end side of the injector 18 when the injector 18 is fixed, and the flange 18f located at a substantially central portion of the injector 18 is compressed. After engaging the circlip 26 in the annular groove 24 so as to be located on the other end side, the injector 18 is slightly returned to the other end side using the restoring function of the gasket 28, and the annular groove 24 and the wire are formed. The clearance for assembly with the circlip 26 is eliminated.

As shown in FIGS. 4 (a) and 4 (b), the circlip 26 has a substantially annular injector holding portion 26-1 which engages with the annular groove 24, and the injector holding portion 26- Excision part 26 which excised the middle part of 1
-2, and a gripping flange 26-3 extending in a direction from both ends of the injector holding portion 26-1. The distance between the gripping flanges 26-3 is defined as S1, the length of the gripping flanges 26-3 is defined as L1, and the gripping flanges 26-3 are defined as L1.
-3 is a projection distance from the injector holding portion 26-1 to the outside in a direction S3.

As shown in FIGS. 1 and 2, the delivery pipe 20 has a mounting portion 30 for mounting to the cylinder head 4. The mounting portion 30 is mounted on the cylinder head 4 via a spacer 32. It is attached with bolts 34.

Reference numeral 36 denotes an O-ring, and reference numeral 38 denotes a coupler.

Next, the operation will be described.

An injector 18 is mounted on the cylinder head 4.
Is fixed, one end of the injector 18 is inserted into the insertion hole portion 22 a of the support portion 22 via the gasket 28.

When the injector 18 is fixed, the gasket 28 is compressed by the step 18a at one end of the injector 18 so that the gasket 28 is located in the annular groove 24 so as to be located at the other end of the flange 18f located substantially at the center of the injector 18. Is engaged with the circlip 26.

At this time, the gasket 28 causes the injector 18 to slightly return to the other end by the recovery function,
The gap for assembly between the annular groove 24 and the circlip 26 made of a wire is eliminated.

The other end of the injector 18 is
The delivery pipe 20 is mounted via the ring 36, and the mounting portion 30 of the delivery pipe 20 is mounted on the cylinder head 4 by the mounting bolt 34 via the spacer 32.

Accordingly, the conventional holding clamp, bolt and mounting member can be eliminated by the support portion 22 and the annular groove 24 formed in the cylinder head 4 and the circlip 26 engaged in the annular groove 24. The number of parts can be reduced, the number of parts can be reduced, the cost can be reduced, it is economically advantageous, and it can contribute to weight reduction, which is practically advantageous. With the abolition, the cylinder head 4 can be simplified, and the width of the layout of the water passage, the oil passage, and the like can be increased.

Further, since the degree of freedom of the connector position is large, that is, it is possible to fix the connector at an arbitrary position, the injector 18 injects fuel with a certain angular direction from the axial direction of the injector. The fuel injection direction can be changed, which is practically advantageous.

Further, an annular groove 24 is formed in the cylinder head 4.
Is formed, the accuracy of the position from the combustion chamber 8 is improved by the amount that no other parts are interposed, and there is no need to consider the tolerance of other parts, and the position between the combustion chamber 8 and the injector 18 There is no variation in the relationship, which is practically advantageous.

Further, the bottom portion 22b of the support portion 22
And the elastic compressible gasket 28 is interposed between one end of the injector 18 and the injector 18 is slightly returned to the other end side by using the restoring function of the gasket 28, and the annular groove 24 and the wire are formed. Circlip 2
6 can be eliminated.

Further, since the circlip 26 is provided with the flange 26-3 for gripping, the circlip 26 can be easily handled when contracted, and the usability can be improved.

It should be noted that the present invention is not limited to the above-described embodiment, and various applications and modifications are possible.

For example, in the embodiment of the present invention, when the circlip 26 is formed of a wire, the flange 26-3 for gripping is provided. However, as shown in FIG. The circlip 42 having a simple shape can improve the manufacturability, reduce the material cost, and eliminate the bending die.

Further, in the embodiment of the present invention, the circlip is formed of a wire, but the distance between the flanges 26-3 for gripping the circlip 26 in FIG. Cut part 42-2 of clip 42
Is the distance S2 with respect to the maximum diameter D of the injector 18 excluding the flange portion 18f when the distance S2 is S2.
1 and S2 are slightly smaller and the injector 18
The circlip can also be formed by a flat plate material other than a wire material, as long as the circlip can be held at the maximum diameter D portion.

Further, when forming the circlip 52,
As shown in FIG. 6, the end portions 5 are formed of a flat plate material and have slightly larger widths on both side portions of the cutout portion 52-2.
2a and 52b are formed, and through holes 54a and 54b are formed in the ends 52a and 52b, respectively.

When the circlip 52 is contracted, a jig or the like is inserted into the through-holes 54a and 54b.
The distance between the cutouts 52-2 can be reduced, the handling of the circlip 52 becomes easy, and the usability can be improved.

Further, the inner peripheral surface 22c of the support portion 22
And an annular inclined groove 62 whose inner diameter gradually increases toward the injection port side of the injector.
A special configuration may be provided in which a circlip 66 with a sloping surface 64 that engages within 2 is provided.

The inner peripheral surface 22c of the support portion 22
After the injector is inserted into the annular inclined groove 62, the circlip 66 is engaged in the annular inclined groove 62, and the circlip 66 is enlarged in the direction of arrow A in FIG. 62, and the inclined surface portion 62a of the annular inclined groove 62 is
4 slides in the injector pressing direction, that is, the direction of arrow B in FIG. 7, so that the injector can be reliably pressed and fixed without using a gasket having a restoring function, and the inclined surface portion 62 a of the annular inclined groove 62 can be fixed. The inclined surface 64 of the circlip 66 can also prevent loosening after fixing the injector, which is practically advantageous.

When a gasket having a restoring function is used, the inner diameter gradually increases in the direction opposite to the inclination direction of the above-described annular inclined groove, that is, toward the side away from the injection port side of the injector. An annular inclined groove can also be formed.

In this case, the injector can be securely fixed while utilizing the restoring function of the gasket, and the mountability of the circlip can be improved. The circlip can be pressed by the restoring function of the gasket to the side away from the injection port side, and the circlip can be effectively prevented from falling off.

[0050]

As described in detail above, according to the present invention, one end of the injector is supported by the cylinder head of the internal combustion engine so as to be directed to the combustion chamber, and the other end is fitted to the delivery pipe. In the mounting structure of the fuel injection device that supports by fixing the cylinder head, a support portion that supports one end side of the injector is provided on the cylinder head, and an annular groove is provided on an inner peripheral surface provided on the support portion,
Since the circlip that engages in the annular groove to fix the injector is provided, the conventional holding clamp, bolt, and mounting member can be eliminated, the number of parts can be reduced, the cost can be reduced, and economy can be reduced. And can contribute to weight reduction, is practically advantageous, and can simplify the cylinder head with the elimination of the conventional holding clamps, bolts, and mounting members. The width of the layout such as the oil passage and the oil passage can be increased. Also,
Since the degree of freedom of the connector position is large, that is, it is possible to fix the connector at an arbitrary position, the fuel injection direction is changed in the case where the injector injects fuel with a certain angular direction from the injector axial direction. This is practically advantageous. Furthermore, by forming the annular groove in the cylinder head, the accuracy of the position from the combustion chamber is improved by the amount that no other parts are interposed, and it is not necessary to take into account the tolerance of other parts, and the combustion chamber is not required. There is no variation in the positional relationship between the actuator and the injector, which is practically advantageous.

[Brief description of the drawings]

FIG. 1 is a schematic enlarged sectional view of an injector mounting portion showing an embodiment of the present invention.

FIG. 2 is a schematic sectional view of an injector mounting portion.

3 is a cross-sectional view of FIG. 2, in which one side of a line segment located at a substantially central portion is a cross-sectional view along line 3A-3A in FIG. 2, and the other end is a cross-sectional view along line 3B-3B in FIG. is there.

FIG. 4 shows a circlip, (a) is a front view, (b)
Is a right side view.

FIG. 5 is a front view of a circlip showing another first embodiment of the present invention.

FIG. 6 shows a circlip according to another second embodiment of the present invention, wherein (a) is a front view and (b) is 6b-6 in FIG. 6 (a).
It is sectional drawing by the b line.

FIG. 7 is a schematic enlarged sectional view of an engagement portion between an annular inclined groove of a support portion and a circlip, showing a third embodiment of the present invention.

[Explanation of symbols]

 2 Internal combustion engine 4 Cylinder head 6 Cylinder head cover 8 Combustion chamber 10 Intake port 12 Exhaust port 14 Intake valve 16 Exhaust valve 18 Injector 18f Flange part 20 Delivery pipe 22 Support part 22a Insertion hole part 22b Bottom part 22c Inner peripheral surface 24 Annular groove 26 Circlip 28 gasket 26-1 injector holding section 26-2 cutout section 26-3 flange section 30 mounting section 32 spacer 34 mounting bolt

Claims (3)

[Claims] Attachment of a fuel injection device in which one end of an injector is supported by a cylinder head of an internal combustion engine so as to be directed to a combustion chamber, and the other end is fitted to a delivery pipe and supported by fixing the delivery pipe. In the structure, a support portion for supporting one end side of the injector is provided in the cylinder head, and an annular groove is provided in an inner peripheral surface provided in the support portion, and a circlip engaging in the annular groove to fix the injector. A mounting structure for a fuel injection device, comprising: 2. The injector has a step on one end side, the support portion includes an insertion hole into which one end of the injector is inserted, a bottom portion corresponding to the step around the insertion hole,
2. The fuel injection device according to claim 1, further comprising an inner peripheral surface around the bottom surface portion, wherein a compressible gasket is interposed between the bottom surface portion and the step portion of the injector when fixing the injector. 3. Mounting structure. 3. The support portion has an annular inclined groove having an inner diameter gradually increasing toward the injection port side of the injector on an inner peripheral surface, and the annular inclined groove is engaged with the annular inclined groove and biased by the biasing force. 2. The mounting structure for a fuel injection device according to claim 1, further comprising a circlip having an inclined surface for slidingly pressing the injector by sliding the groove.