JPH03237260A - Method of fitting strainer for solenoid fuel injection valve - Google Patents

Abstract

PURPOSE:To omit a strainer press-in process so as to reduce aggregate for securing rigidity and enlarge a filtering area by covering the fuel inlet part of a solenoid fuel injection valve with a net used for a strainer, and then fixing them rigidly. CONSTITUTION:At the time of fitting a strainer at the fuel inlet part 12 of a solenoid fuel injection valve 10, a fuel filtering metal net 2 used for a strainer is cut first, and both ends of the net 2 are welded to form cylindrical shape. The net 2 is then placed to cover the fuel inlet part 12. The solenoid fuel injection valve 10 covered with the net 2 is put into a resin mold, and then the end parts of the net 2 are resin-molded so as to fix the net 2 and the solenoid fuel injection valve 10 rigidly. Afterwards, the solenoid fuel injection valve 10 is taken out of the mold to terminate fitting work. Since a press-in process in a strainer fitting process is omitted in this way, aggregate 4 for securing rigidity can be reduced, and thereby a filtering area can be enlarged.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for attaching a strainer to the fuel inlet portion of an electromagnetic fuel injection valve.

[Conventional technology]

Conventionally, as a method for attaching a strainer to a fuel inlet portion of an electromagnetic fuel injection valve, a method has been adopted in which a pre-formed strainer is press-fitted and fixed to the electromagnetic fuel injection valve.

This alternative is illustrated in FIGS. 6-8 attached hereto.

FIG. 6 shows a molded strainer l.

In the figure, 2 is a cylindrical wire mesh used as a fuel source, and resin aggregates 4a and 4b are provided at the edges and in the axial direction to ensure rigidity that allows the strainer 1 to be press-fitted. It is being

Figure 7 shows the strainer l formed on the electromagnetic fuel injection valve lO.
The state before press-fitting is shown.

Here, the electromagnetic fuel injection valve lO is a side feed type electromagnetic fuel injection valve, and pressurized fuel supplied from a delivery pipe (not shown) is introduced from the fuel inlet portion 12 on the side of the electromagnetic fuel injection valve 10. It is supplied inside through the port 12a.

The strainer l is press-fitted from the outside so as to cover the fuel population portion 12 on the side surface of the electromagnetic fuel injection valve lO.

FIG. 8 shows the state after the molded strainer I is press-fitted into the electromagnetic fuel injection valve 10.

[Problem to be solved by the invention]

However, according to the above method, the strainer l needs to have enough rigidity to withstand press-fitting, and in order to ensure this rigidity, the edges and axial direction of the strainer 1 are made of aggregate 4a.
, 4b are required. Therefore, the filtration area of the strainer 1 is reduced by at least the area of the aggregate 4b in the axial direction.

Furthermore, in order to enable press-fitting, it is necessary to maintain the manufacturing accuracy of the strainer l to a certain degree, which increases the manufacturing cost.

Furthermore, after press-fitting, vibrations and the surrounding high-temperature atmosphere may cause loosening, and there is a risk that foreign matter may be mixed in.

The present invention aims to solve the above problems by improving the strainer attachment method based on the above findings.

[Means to solve the problem]

The above problem is solved by a method for attaching a strainer to an electromagnetic fuel injection valve, which will be described below.

The strainer of the electromagnetic fuel injection valve is attached to the fuel inlet part based on the following process.

First, there is a step of cutting the net used for the strainer.

Next, there is a step of covering the fuel inlet portion of the electromagnetic fuel injection valve with the cut mesh.

Next, there is a step of fixing the net and the electromagnetic fuel injection valve.

[For production]

According to the strainer installation method for an electromagnetic fuel injection valve that has the above steps, since the step of press-fitting the strainer is omitted, there is no need to maintain the rigidity of the strainer itself, and the strainer is not required to maintain the rigidity required during press-fitting. Materials can be reduced.

Therefore, the strainer can have a large filtration area.

In addition, since the cut mesh is placed over the fuel inlet of the electromagnetic fuel injection valve and then fixed together, the strainer can be reliably attached to the electromagnetic fuel injection valve, and further,
There is no need to keep the manufacturing precision of the strainer itself very high.

〔Example〕

1 to 3 show a first embodiment of the present invention, and show a method of attaching a strainer to a fuel inlet portion 12 of a side-feed type electromagnetic fuel injection valve 10. FIG.

Figure 1 (a) shows a side-feed type electromagnetic fuel injection valve l.
0, which shows the condition before the strainer is fixed.

The electromagnetic fuel injection valve 10 has a structure in which pressurized fuel supplied from a delivery pipe (not shown) is guided into the interior from a fuel inlet portion 12 on the side.

FIG. 1(b) shows the fuel inlet portion 12 of the electromagnetic fuel injection valve 10.
2 shows a cylindrically shaped fuel source application mesh 2 which is placed over the

FIG. 2 shows the process of attaching a strainer to the fuel inlet portion 12 of the side-feed type electromagnetic fuel injection valve IO.

FIG. 2(a) shows a metal mesh 2a used as a strainer before being cut. This mesh 2a is cut to match the area of the fuel inlet portion 12 (see figure b).

Next, weld both ends of net 2 to make it into a cylindrical shape (see figure 0).
.

Next, the cylindrical mesh 2 is placed over the fuel inlet portion 12 of the electromagnetic fuel injection valve lO (see figure d).

Next, with the cylindrical mesh 2 placed over the fuel inlet portion 12 of the electromagnetic fuel injection valve IO, both are placed in a mold 20 for resin molding, and the ends of the mesh 2 are molded with resin. Fix the electromagnetic fuel injection valve lO (see figure e). This completes the strainer installation.

Finally, the electromagnetic fuel injection valve lO is taken out from the mold 20, and the work is completed (see figure f). In addition, illustration 4 shows the resin part (aggregate) molded in the step (e).

Figure 3 shows the electromagnetic fuel injection valve lO after the strainer is installed.
It shows.

In this way, since the press-fitting process is omitted during the strainer installation process, the amount of aggregate 4 needed to ensure the rigidity of the strainer during press-fitting can be reduced. Therefore, the filtration area can be increased by the amount of aggregate 4.

As a result, the strainer is less likely to be clogged with dirt and the like, and even if vapor is generated due to fuel vaporization within the electromagnetic fuel injection valve IO when the engine is at high temperature, the vapor can be easily discharged.

In addition, since the cut mesh 2 is placed over the fuel inlet portion 12 of the electromagnetic fuel injection valve 10 and then both are placed in the mold 20 and fixed by resin molding, the strainer can be fixed securely and heated. This can prevent foreign matter from entering over a long period of time, even if loosening occurs due to vibration or vibration.

Furthermore, there is no need to maintain the manufacturing precision of the strainer itself so high, and manufacturing costs are reduced.

FIG. 4 shows a second embodiment of the invention. In this embodiment, a groove lOa is provided around the artificial part 12 of the fuel, and resin is injected into the groove 10a during resin molding.

This structure prevents loosening of the resin molded part of the strainer.
Furthermore, it is becoming less likely to occur.

Although the above example uses a metal net as the fuel filtering net 2, it goes without saying that a resin net can also be used.

FIG. 5 shows a third embodiment of the present invention. This embodiment shows a method in which the wire mesh 2 of the strainer is placed over the fuel inlet portion 12 of the electromagnetic fuel injection valve 10 and then fixed by welding or brazing.

According to this method, the fixation becomes more reliable than in the case of resin molding.

〔Effect of the invention〕

According to the present invention, since the strainer does not require much rigidity, the amount of aggregate can be reduced and a large filtration area can be secured. Therefore, the strainer is less likely to be clogged with dirt, etc., and even if vapor is generated due to fuel vaporization within the electromagnetic fuel injection valve when the engine is at high temperature, the vapor can be easily discharged.

Furthermore, since the cut mesh is placed over the fuel inlet of the electromagnetic fuel injection valve and then fixed, the fixation is highly reliable and is less likely to come loose due to heat, vibration, etc. Therefore, entry of foreign matter can be prevented for a long period of time.

Furthermore, since it is not necessary to keep the manufacturing precision of the strainer itself very high, manufacturing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a side-feed type electromagnetic fuel injection valve according to a first embodiment of the present invention and a diagram showing a cylindrical fuel filtering net, and FIG. 2 is a diagram showing a first embodiment of the present invention. FIG. 3 is a diagram showing the strainer installation process according to the first embodiment of the present invention, FIG. 4 is a diagram of the strainer installation according to the second embodiment of the present invention, and FIG. FIG. 6 is a diagram showing a strainer installation according to the third embodiment of the invention, FIG. 6 is a diagram showing a strainer according to the prior art, and FIG. 7 is a diagram showing a side feed type electromagnetic fuel injection valve according to the prior art and a cylindrical strainer. Figure 8 showing
The figure is a diagram showing a completed installation of a strainer according to the prior art. 12...Fuel inlet part

Claims (1)

[Scope of Claims] A method for attaching a strainer to a fuel inlet portion of an electromagnetic fuel injection valve, the method comprising: cutting a mesh to be used for the strainer; and attaching the cut mesh to the fuel inlet portion of the electromagnetic fuel injection valve. A method for attaching a strainer to an electromagnetic fuel injection valve, comprising: a step of covering the mesh with the electromagnetic fuel injection valve; and a step of fixing the mesh and the electromagnetic fuel injection valve.