JP2000008995A - Fuel delivery pipe structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel delivery pipe structure excellent in assembling properties, without causing setup positional error, while holding the characteristic of a plastic fuel delivery pipe. SOLUTION: This delivery pipe structure comprises a plastic delivery pipe body 4 and a fixture such as a metal collar 5 or the like for attaching this pipe body 4 to an intake manifold 2, and the delivery pipe body 4 is formed of a synthetic resin whereby a manufacturing cost is reduced while such as effect that the generation of vapor in a returnless mode is suppressed by large adiabatic efficiency is secured, and it is mounted by the metal collar 5, and thereby no setup positional error is caused, through while assembling properties are improved and the capacity of sealing performance by an O-ring in a mounting hole of an injector is secured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel delivery pipe structure, and more particularly to a fuel delivery pipe structure for distributing and supplying fuel to injectors mounted on an intake manifold for each cylinder.

[0002]

2. Description of the Related Art A conventional fuel delivery pipe is disclosed, for example, in Japanese Utility Model Laid-Open No. 5-78966.
Although it was constituted by a metal pipe, in recent years, it has the advantage that the cost can be reduced and the generation of vapor can be suppressed even in the returnless method due to the large heat insulation effect, as shown in FIGS. 6 and 7. In addition, a fuel delivery pipe made of a synthetic resin has been proposed.

In FIG. 6 and FIG. 7, reference numeral 21 denotes a fuel delivery pipe made of synthetic resin. It is constituted by a mounting leg 23 having a long leg length which is protruded from the outside. At the tip of the mounting leg 23, an L-shaped mounting flange portion 24 is protruded, and a bolt hole 24a is formed. The fuel delivery pipe 21 is mounted on the intake manifold 25 by fastening and fixing the mounting flange portion 24 to a mounting seat 25 a protruding from the intake manifold 25 with bolts. An intake port is provided between the injector mounting portion 26 formed in the delivery pipe body 22 corresponding to the intake port of each cylinder and the injector mounting hole (not shown) formed in the intake manifold 25. It was configured to interpose an injector (not shown) for injecting fuel.

[0004]

However, in the conventional structure described above, the fuel delivery pipe mounting seat in the intake manifold 25 is provided so as not to interfere with the tool 28 for mounting the intake manifold 25 to the cylinder head 27. 25a cannot be increased, and the mounting legs 23 need to be lengthened. Therefore, the mounting strength and rigidity of the delivery pipe main body 22 are insufficient, and the mounting legs 23 are affected by warpage and thermal deformation after molding. There has been a problem that the positioning accuracy of the delivery pipe main body 22 is deteriorated, and the sealing performance due to the one-side contact of the built-in O-ring is reduced due to the displacement of the mounting hole of the injector. In addition, there is a problem that it is difficult to align the screw hole of the mounting seat 25a with the bolt hole 24a of the mounting flange portion 24 due to warping or thermal deformation of the long mounting leg 23 after molding, resulting in poor assemblability, and On the other hand, it is conceivable that a stud bolt is erected on the mounting seat 25a, but there is a problem that it cannot be erected because it interferes with the tool 28 as described above. In addition, there is a problem that loosening of the mounting bolt is caused due to set of the mounting flange portion 24 made of synthetic resin.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention maintains the features of a fuel delivery pipe made of synthetic resin, and does not cause mounting position errors due to insufficient mounting strength, warpage after molding, or thermal deformation. It is an object of the present invention to provide a fuel delivery pipe structure having good performance.

[0006]

The fuel delivery pipe structure of the present invention comprises a delivery pipe body made of synthetic resin and a metal fitting for attaching the delivery pipe body to the intake manifold. Since the delivery pipe body is made of synthetic resin, the cost can be reduced and the heat insulation effect is large, so that the generation of vapor in the returnless method can be suppressed. Therefore, there is no mounting position error due to insufficient mounting strength, warpage after molding or thermal deformation, the sealing performance of the O-ring in the mounting hole of the injector can be ensured, and the assemblability is good.

[0007] Further, if the mounting member is constituted by a metal collar whose one end is fitted and fixed in a mounting hole formed in the delivery pipe body and which can be fixed to the intake manifold by penetrating a mounting bolt, the structure is simple. In addition, it is possible to firmly attach by simply inserting and fastening the mounting bolt, and the assembling property is further improved.

Further, if a positioning portion for fitting and positioning the other end of the metal collar is provided in the intake manifold, higher positional accuracy can be ensured.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the fuel delivery pipe structure of the present invention will be described below with reference to FIGS.

In FIG. 1, 1 is a fuel delivery pipe,
2 is an intake manifold to which the fuel delivery pipe 1 is attached, 3 is a base end of the fuel delivery pipe 1,
The tip is an injector mounted on the intake manifold 2.

As shown in detail in FIGS. 2 and 3, the fuel delivery pipe 1 comprises a synthetic resin straight delivery pipe main body 4 having reinforcing ribs 4a protruding on its outer surface as appropriate.
It is composed of a metal mounting collar 5. The delivery pipe body 4 has a fuel passage 6 formed in the axial center thereof along the longitudinal direction, and a mounting portion 7 protruding from a position corresponding to each cylinder (three cylinders in the illustrated example). A mounting hole 8 is formed in the mounting portion 7 so as to communicate with the fuel passage 6, and is configured so that the base end of the injector 3 is fitted and mounted. An O-ring (not shown) is provided in the mounting hole 8, and the seal is secured by fitting the base end of the injector 3.

A pair of mounting flanges 9 are protruded from both ends of the delivery pipe main body 4 at positions inside the pair of mounting portions 7. The mounting flange portion 9 has an L-shape extending slightly from the delivery pipe body 4 toward the intake manifold 2 and then extending the flange portion 9a toward the side. The mounting portion formed through the flange portion 9a. A small diameter portion 5a at one end of the mounting collar 5 is fitted and fixed in the hole 9b. The length of the small diameter portion 5a and the thickness of the flange portion 9a are substantially the same, and the upper surface of the flange portion 9a and the tip of the small diameter portion 5a are substantially flush.

The mounting collar 5 is set relatively long so that the distance between the mounting portion 7 of the delivery pipe main body 4 and an injector mounting portion 16 of the intake manifold 2 described later corresponds to the length of the injector 3. . At the intake manifold 2, a mounting projection 11 is protruded low at a mounting location of the mounting collar 5, a mounting seat 12 is formed in the mounting projection 11 by forming a counterbore, and a screw hole 13 is formed at the center of the mounting seat 12. Are formed. 12a is the mounting collar 5
Is positioned by fitting the other end of the mounting seat, and is formed by a surrounding wall of a counterbore hole forming the mounting seat 12. 10 is a mounting bolt, and a mounting collar 5
And the fuel delivery pipe 1 is attached to the intake manifold 2.

The intake manifold 2 is shown in FIGS.
As shown in FIG. 1, a plurality of intake pipes 15 for supplying intake air to an intake port of the cylinder head are integrally joined to a joint flange 14 joined to a side surface on an intake side of a cylinder head (not shown). Joint flange 14 and intake pipe 15
An injector mounting portion 16 is provided at an upper portion of the joint at the distal end to form a mounting hole 17 for fitting and mounting the distal end of the injector 3, and is configured to inject fuel toward the intake port. ing.

According to the above construction, the other end of the mounting collar 5 of the fuel delivery pipe 1 is brought into contact with the mounting seat 12, the mounting bolt 10 is inserted through the mounting collar 5, and the fuel is merely fastened to the screw hole 13. The delivery pipe 1 can be attached to the intake manifold 2, and at that time, the mounting seat 1
Since the other end of the mounting collar 5 is positioned by the second peripheral wall 12a, the work of screwing the mounting bolt 10 into the screw hole 13 can be performed extremely easily, and the fuel delivery pipe 1 can be assembled with good workability. .

Further, since the delivery pipe body 4 is made of synthetic resin, the cost can be reduced and the heat insulation effect is large, so that the generation of vapor can be suppressed even if a fuel supply system of a returnless system is adopted.

Since the mounting collar 5 is made of metal,
Since the arrangement position error due to insufficient mounting strength, warpage after molding and thermal deformation does not occur, the assembling workability is further improved, and the base end of the injector 3 is fitted into the mounting hole 8 of the delivery pipe main body 4. In this state, the sealing performance of the O-ring can be secured, and since the mounting bolt 10 fastens the metal mounting collar 5, the mounting flange 9 made of synthetic resin is not firm enough to obtain a sufficient tightening torque. Therefore, the fuel delivery pipe 1 can be stably attached to the intake manifold 2.

[0018]

According to the fuel delivery pipe structure of the present invention, since the delivery pipe body is made of synthetic resin as described above, the cost can be reduced and the heat insulation effect is large, so that the generation of vapor in the returnless system is achieved. It has the effect of reducing the mounting position, and because it is mounted with a metal fitting, it does not cause mounting position errors due to insufficient mounting strength, warping after molding or thermal deformation, and sealing by the O-ring of the injector mounting hole The effect that the performance can be secured and the assemblability is good can be obtained.

Further, when the attachment is constituted by a metal sleeve whose one end is fitted and fixed in an attachment hole formed in the delivery pipe main body and which can be fixed to the intake manifold by penetrating an attachment bolt, the construction is simple. And it can be installed firmly only by inserting and fastening the mounting bolt,
The assemblability is further improved.

Further, if the intake manifold is provided with a positioning portion for positioning by fitting the other end of the metal collar, higher positioning accuracy can be ensured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an attachment state of a fuel delivery pipe structure to an intake manifold according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a BB view of FIG. 2 showing the fuel delivery pipe structure of the embodiment.

FIG. 4 is a front view of an intake manifold according to the embodiment.

FIG. 5 is a sectional view taken along the line CC of FIG. 4;

FIG. 6 is a cross-sectional view showing a state in which a conventional fuel delivery pipe is attached to an intake manifold.

FIG. 7 shows a fuel delivery pipe of the conventional example, and FIG.
Is a front view, and (b) is a cross-sectional view taken along the line DD of (a).

[Explanation of symbols]

 Reference Signs List 1 fuel delivery pipe 2 intake manifold 4 delivery pipe main body made of synthetic resin 5 metal mounting collar 5a small diameter section 9 mounting flange section 9b mounting hole 10 mounting bolt 12 mounting seat 12a positioning peripheral wall

Claims (3)

[Claims] 1. A fuel delivery pipe structure comprising: a delivery pipe body made of a synthetic resin; and a metal fitting for attaching the delivery pipe body to an intake manifold. 2. The mounting member is made of a metal collar having one end fitted and fixed in a mounting hole formed in the delivery pipe main body, and capable of being fixed to the intake manifold by passing a mounting bolt therethrough. 2. The fuel delivery pipe structure according to 1. 3. The fuel delivery pipe structure according to claim 2, wherein a positioning portion for fitting and positioning the other end of the metal collar is provided on the intake manifold.