JP2562985Y2 - Fuel injection nozzle mounting device for internal combustion engine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel injection nozzle mounting device for an internal combustion engine, and more particularly to an improvement in the structure of a clamp member of a nozzle holder.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, as a fuel injection nozzle mounting device for an internal combustion engine, a lower end of one side of a clamp member 1 is in contact with a cylinder head 2 and a lower end of the other end is connected to a nozzle holder 3. The bolt 4 is inserted into the bolt insertion hole 5 at the intermediate portion of the clamp member 1 and screwed into the cylinder head 2, and the nut 4 is fitted to the bolt 4 via the washer 6 and tightened, thereby tightening the clamp member 1. No. 1 discloses a technique in which the nozzle holder 3 is fixed to the cylinder head 2 (see Japanese Utility Model Laid-Open Nos. 58-30763 and 64-47978).

The d dimension in FIG. 5 is the inner diameter of the bolt insertion hole 5, and the B dimension is the thickness of the clamp member 1. The D dimension and the d dimension determine the thickness of the dangerous sectional view. .

[0004]

However, in such a conventional fuel injection nozzle mounting apparatus, when the nozzle holder 3 is fixed to the cylinder head 2 by the clamp member 1, a processing error of the clamp member 1 or the like is required. 5 due to expansion deformation due to heat or the like, deformation of the cylinder head 2 or the like.
And mounting heights H ₁ and H _{2 of} the nozzle holder 3 shown in FIG.
Changes to the relationship of H ₁ ≠ H ₂ , and the lower end edge of the inner peripheral portion of the clamp member 1 and the bolt 4 come into contact with each other when the clamp member 1 is inclined at an angle of θ as shown in FIG. There is a problem in that bending stress is applied to the bolt 4, which leads to deformation, breakage, and the like of the bolt 4.

For this reason, the diameter of the bolt 4 is increased,
Although it is conceivable to form the clamp member 1 large,
This increases the weight of parts and goes against the downsizing of the engine, which is not a good solution. Conventionally, Japanese Utility Model 63-20
No. 813 discloses that the mounting flange of the exhaust manifold slides (moves) to thermal expansion in a lateral direction due to thermal expansion, so that the mounting flange and the bolt come into contact with each other, and thermal stress is generated at the root of the mounting flange. There is known a technique in which a tapered bolt hole is provided in a mounting flange in order to prevent a crack from occurring.

In view of the above, the present invention has been made in view of the above, and it is desirable to prevent deformation, breakage, and the like of a bolt without impairing the outer shape, strength, and rigidity of the clamp member and without changing the bolt size. Aim.

[0007]

According to the present invention, a lower end of one side of a clamp member is in contact with a cylinder head and a lower end of the other end is in contact with a nozzle holder, and a bolt is inserted into a bolt insertion hole in an intermediate portion of the clamp member. In the fuel injection nozzle mounting device for an internal combustion engine, wherein the nozzle holder is fixed to the cylinder head by a clamp member by being inserted into the cylinder head and tightened to the cylinder head, the bolt insertion hole is provided with the clamp member, the cylinder head, and the nozzle holder. In the shape of a long hole that extends long toward each of the contact portions.

[0008]

The interference between the clamp member and the bolt can be prevented even if the clamp member is tilted due to a processing error, thermal expansion, or the like, and abnormal stress can be prevented from being applied to the bolt. In addition, the thickness of the bolt insertion hole cross section in the direction orthogonal to the direction of the abutting portion between the clamp member and the cylinder head and the nozzle holder, that is, the thickness of the dangerous cross section can be as thick as the conventional one, so the outer shape should be large. And the same strength and rigidity as before can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings described below, the same elements as those in FIGS. 5 and 6 are denoted by the same reference numerals. That is, in FIG. 1 and FIG.
And the lower end of the other end thereof is brought into contact with the nozzle holder 3, and the bolt 4 is inserted into the bolt insertion hole 15 in the intermediate portion of the clamp member 1 and screwed into the cylinder head 2, and the bolt 4 is inserted through the washer 6. The structure in which the nozzle holder 3 is fixed to the cylinder head 2 by the clamp member 1 by fitting and tightening the nut 7 is the same as the conventional one.

Here, the point different from the conventional one is that the bolt insertion hole 15 is formed in a long hole shape that extends long toward each contact portion between the clamp member 1, the cylinder head 2 and the nozzle holder 3. is there. In this case, the bolt insertion hole 15 is formed as a tapered hole whose longer side gradually becomes longer toward the cylinder head 2 side. Alternatively, as shown in FIG. 4, the bolt insertion hole 15 may simply be formed as a straight hole having a uniform long side.

In FIG. 1, the dimension D is the length of the longest side of the bottom of the bolt insertion hole 15, the dimension d is the length of the longest side of the top of the bolt insertion hole 15, and D 'is the approximate length of the bolt insertion hole 15. The length of the long side of the intermediate portion, B dimension is the thickness of the clamp member 1,
The D dimension and the d dimension determine the thickness of the dangerous sectional view. According to such a configuration, the bolt insertion hole 15 has a long hole shape that extends long toward each of the contact portions between the clamp member 1 and the cylinder head 2 and the nozzle holder 3. Even if the member 1 is inclined, interference between the clamp member 1 and the bolt 4 can be prevented,
Abnormal stress can be prevented from being applied to the bolt 4.

That is, as shown in FIG.
And the mounting heights H ₁ and H _{2 of} the nozzle holder 3 shown in FIGS. 1 and 3 change to the relation of H ₁ ≠ H ₂ ,
There is no contact between the lower end edge of the inner peripheral portion of the clamp member 1 and the bolt 4, and therefore, deformation or breakage of the bolt 4 due to bending stress applied to the bolt 4 does not occur. Further, the cross section of the bolt insertion hole 15 in the direction orthogonal to the direction of contact between the clamp member 1 and the cylinder head 2 and the nozzle holder 3, that is, the thickness of the dangerous cross section can be as thick as that of the conventional art. The same strength and rigidity as before can be obtained without increasing the outer shape.

It should be noted that the present invention is not limited to the configuration of the embodiment, and various changes can be made based on the claims of the utility model registration.

[0014]

As described above, the present invention provides a fuel injection nozzle mounting apparatus for an internal combustion engine in which a nozzle holder is fixed to a cylinder head by a clamp member fastened by a bolt. The holes are elongated holes that extend long toward the contact part between the clamp member and the cylinder head and nozzle holder, so that interference between the clamp member and the bolt can be prevented even if the clamp member is inclined due to processing errors or thermal expansion. It can prevent abnormal stress from being applied to the bolt, and can prevent deformation and breakage of the bolt.Moreover, the thickness of the dangerous cross section can be kept the same as before, so that the outer shape is not increased. The same strength and rigidity as those of the related art can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a fuel injection nozzle mounting device for an internal combustion engine according to the present invention, wherein FIG.
(B) is a sectional view taken along the arrow BB in (A), and (C) is a sectional view taken along the arrow CC in (A).

FIG. 2 is an enlarged sectional view of the bolt insertion hole of the embodiment.

FIG. 3 is a front vertical sectional view illustrating advantages of the embodiment.

4A and 4B are diagrams showing the shape of a bolt insertion hole according to another embodiment, wherein FIG. 4A is a plan view and FIG.

5A and 5B are views showing a conventional fuel injection nozzle mounting device for an internal combustion engine, in which FIG. 5A is a front vertical sectional view, FIG.
(C) is a sectional view taken along the line AA in (A).

FIG. 6 is a front vertical sectional view showing a problem of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Clamp member 2 Cylinder head 3 Nozzle holder 4 Bolt 15 Bolt insertion hole

Claims (1)

(57) [Scope of request for utility model registration] An end of one side of a clamp member is in contact with a cylinder head, and a lower end of the other end is in contact with a nozzle holder, and a bolt is inserted into a bolt insertion hole in an intermediate portion of the clamp member and fastened to the cylinder head. Thereby, in the fuel injection nozzle mounting device of the internal combustion engine in which the nozzle holder is fixed to the cylinder head by the clamp member, the bolt insertion hole is provided on each of the contact portions between the clamp member, the cylinder head, and the nozzle holder. A fuel injection nozzle mounting device for an internal combustion engine, wherein the fuel injection nozzle mounting device has a long hole shape extending long toward the fuel cell.