JPH06294363A - Electromagnetic fuel injection valve - Google Patents

Abstract

PURPOSE:To reduce a cost and size by providing a bobbin which has a divided structure wherein a pipe core is sandwiched between a front and a rear plates, and forming a resin flowing port on a body, for molding a connector. CONSTITUTION:A ring-like non-magnetic plate 2 and a soft ring-like magnetic plate 4 are soldered respectively to a front end and a center part of a pipe core 1 made of soft magnetic material. Bobbin half bodies 5, 6 obtained by dividing a bottom into two between the plates 2, 4 are united again so as to sandwich the core 1. A resin flowing port 9a penetrating the plates 2, 4 are formed on a magnetic pipe outer body 9 housing a core assembly which is obtained by assembling the half bodies 5, 6 on the core 1 and winding a coil 8. Resin is charged into the body 9 through an electric connecting connector 10 which is molded on a rear part of the core 1, during its molding. The body and the core are inexpensively manufactured from the pipe material. Secondary molding of an O-ring or the bobbin which is conventionally require is dispensed with, and downsizing is enabled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic fuel injection valve mainly used in an electronic fuel injection device in a vehicle engine.

[0002]

2. Description of the Related Art A conventional example of an electromagnetic fuel injection valve will be described with reference to FIG. 8 showing a sectional view thereof. The illustrated fuel injection valve includes a bobbin 81 around which a coil 80 is wound, a hollow core 83 that is disposed inside the bobbin and has a fuel passage 82 inside, a body 84 that internally houses the bobbin 81, and the core. Electrical connection connector 8 resin-molded on 83
5 and. Such an electromagnetic fuel injection valve is disclosed, for example, in Japanese Patent Laid-Open No. 61-283758.

However, in the conventional fuel injection valve, as shown in FIG. 8, the body 84 and the core 83 are both flange portions 8 facing either end surface of the bobbin 81.
It has a complicated shape having 4a and 83a integrally. Further, between the body 84 and the bobbin 81 and the bobbin 8
O-rings 86 and 87 are arranged between the 1 and the core 83,
The fuel passing through the fuel passage 82 is prevented from leaking outside the coil portion and the body. Further, the coil 80 is wound around the bobbin 81 prior to its assembly, and a secondary mold (denoted by reference numeral 88) by resin molding is applied so as to cover the outer periphery thereof.

[0004]

According to the conventional electromagnetic fuel injection valve, since the body 84 and the core 83 have a complicated shape, cold forging and cutting, which require high manufacturing costs, are required. Further, by using the two O-rings 86, 87 for fuel sealing and implementing the secondary mold 88 of the bobbin 81, etc., the costly construction is achieved, and the space required for the O-ring and the secondary mold is secured. There is a problem that it is difficult to reduce the size and diameter.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an electromagnetic fuel injection valve capable of reducing the cost and downsizing.

[0006]

SUMMARY OF THE INVENTION An electromagnetic fuel injection valve of the present invention for solving the above-mentioned problems includes a bobbin around which a coil is wound,
An electromagnetic fuel injection valve comprising a hollow core disposed in the bobbin and having a fuel passage inside, a body containing the bobbin, and a resin-molded electrical connection connector for the core, The core is formed of a pipe material, front and rear plates facing the front and rear end faces of the bobbin are attached to the core, and the bobbin has a two-part structure for sandwiching the core between the two plates, and the body is The body is formed of a pipe material, and a resin through hole that penetrates between the both plates of the core is provided in the body, and the resin at the time of resin molding of the connector is filled in the body through the through hole.

[0007]

According to the above-mentioned means, the body and the core can be obtained by simply molding and processing the pipe material. Further, the two-divided bobbin is sandwiched in the core portion between both plates attached to the core, and the coil is wound around the bobbin, so that the fuel passage portion, the coil portion and the outside of the body are partitioned, This eliminates the need for an O-ring for fuel sealing. In addition, the secondary molding of the coil is performed simultaneously with the resin molding of the connector.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The completed electromagnetic fuel injection valve of this example is shown in a sectional view in FIG. In FIG. 1, a pipe core 1 made of a soft magnetic material and having a hollow portion as a fuel passage 17 is arranged at an axial center portion of the fuel injection valve. The first half of the core 1 has a reduced diameter as a bobbin mounting portion by squeezing or the like. A ring-shaped non-magnetic plate 2 made of a non-magnetic material is joined to the front end of the core 1 by brazing or welding. A rear end portion of the pipe inner body 3 made of a soft magnetic material is joined to the outer peripheral portion of the non-magnetic plate 2 by brazing or welding.
A magnetic plate 4 having a ring shape made of a soft magnetic material and having a part (the upper part in the drawing) cut out is joined to the central portion of the core 1 by brazing or welding. A sectional view of this magnetic plate portion is shown in FIG.

In the core 1, as shown in FIG.
A resin bobbin is attached between the front and rear plates, that is, between the non-magnetic plate 2 and the magnetic plate 4.
This bobbin is constructed by joining bobbin halves 5 and 6 which are divided into two halves in a perspective view in FIG. A plurality of small projections 5 are provided on the mating surfaces of the flange portions 51, 61 of both bobbin halves 5, 6.
a and a small hole 6a corresponding thereto are provided, and both bobbin halves 5 and 6 are integrated by press-fitting the small protrusion 5a into the small hole 6a. One bobbin half 6
The terminal 7 is insert-molded on the flange portion 61 of the.

Bobbin halves 5 and 6 attached to the core 1.
1, the coil 8 is wound in multiple layers as shown in FIG. The end of the coil 8 is electrically connected to the terminal 7. The core assembly 1a is formed by assembling the bobbin halves 5 and 6 and winding the coil 8 on the core 1. This core assembly 1a is shown in cross section in FIG.

The core assembly 1a is assembled in the outer pipe body 9 made of a magnetic material shown in FIG. 1 from the rear of the body (right side of FIG. 1). By this assembly, the front and rear plates 2, 4 and the inner body 3 are closely fitted to the outer body 9. In this example, the outer body 9 is the main body of the fuel injection valve, and the inner body 3 is provided as a reinforcing member for the outer body 9. The outer body 9 is formed with a resin flow hole 9a penetrating between the plates 2 and 4. The rear end of the outer body 9 is fixed to the magnetic plate 4 at a plurality of positions by caulking (FIG. 5).
reference).

An electrical connection connector 10 is formed on the latter half of the core 1 by resin molding as shown in FIG. At the portion of the connector 10, the terminal 7 receives an input from an electronic control unit (not shown) to energize and de-energize the coil 8. Further, the connector 10 is resin-molded so as to cover the joint between the outer body 9 and the core 1 and to fill the resin flow hole 9a of the outer body 9. Therefore, the resin at the time of resin molding is filled in the body through the resin circulation hole 9a of the outer body 9 so that the outer periphery of the coil 8 of the bobbin is secondarily molded. The semi-finished product after resin molding is shown in a sectional view in FIG. 2, and the sectional view of the resin flow hole 9a is shown in FIG.

In the inner body 3 of the semi-finished product, as shown in FIG.
A valve seat 14 having a ring-shaped stopper plate 11 made of a magnetic material and a fuel injection port 14a as shown in FIG.
Are installed in order, and the adapter 1 is further installed in the outer body 9.
5, the outer body 9 is fixed by caulking the tip of the outer body 9. A sectional view of the stopper plate portion is shown in FIG. In FIG. 7, the stopper plate 11 is provided with a recess 11a forming the fuel passage on the inner periphery thereof.

Further, in the axial center portion of the valve seat 14,
As shown in FIG. 1, the valve 13 is slidably incorporated in the axial direction. A cylindrical armature 12 made of a magnetic material and sliding in the stopper plate 11 is fixed to the rear end of the valve 13. The armature 12 is formed with a through hole 12a penetrating inward and outward to form a fuel passage. This armature 12
Receives a suction force from the core 1 when the coil 8 is energized.

The valve 13 is always kept closed with the fuel injection port 14a of the valve seat 14 under the elastic force of a valve spring 19 incorporated between the valve 13 and a pipe 18 which is caulked and fixed in the core 1. Has been done. Between the rear end of the core 1 (the right end in FIG. 1) and the fuel injection port 14a of the valve seat 14, the fuel passage 17 of the core 1
A series of fuel passages including the inside of the through hole 12a of the armature 12, the inside of the recess 11a of the stopper plate 11, and the inside of the valve seat are configured, and the strainer 20 is provided at the inlet of the fuel passage 17 in the rear end of the core 1. It has been incorporated.

The operation of the thus constructed electromagnetic fuel injection valve will be briefly described. The fuel supplied from a fuel tank (not shown) under a predetermined pressure is filtered by the strainer 20 and then supplied. It reaches the inside of the valve seat 14 through the fuel passage. However, since the valve 13 receives the elastic force of the valve spring 19 and the fuel injection port 14a of the valve seat 14 is kept closed by this, the fuel injection from this injection port 14a does not occur.

Here, when the coil 8 is energized by the input of an electric signal from the electronic control unit, the armature 12 together with the valve 13 resists the elasticity of the valve spring 19 by the suction force of the core 1 as described above. fall back. As a result, the valve 13 opens the fuel injection port 14a of the valve seat 14, and the fuel is injected from here. Then, when the electric signal to the coil 8 is turned off and the attraction force of the core 1 acting on the armature 12 is released, the valve 13 is released based on the elasticity of the valve spring 19.
Holds the fuel injection port 14a closed again, and stops the fuel injection from this injection port 14a.

According to the above-mentioned electromagnetic fuel injection valve, the outer body 9 and the core 1 can be obtained at a low manufacturing cost by simply forming and processing the pipe material. In addition, the bobbin halves 5 and 6 that are divided in two are sandwiched between the core portions between the plates 2 and 4 attached to the core 1, and the coil 8 is wound around the bobbin halves 5 and 6. The fuel passage portion is separated from the coil portion and the outside of the body, which eliminates the need for an O-ring for fuel sealing. The coil 8 is secondarily molded at the same time as the resin molding of the connector 10 is performed. Therefore, since the use of the O-ring and the secondary molding of the bobbin, which have been conventionally required, can be eliminated, the cost can be reduced, and the space required for the O-ring and the secondary molding can be reduced to achieve the miniaturization.

[0019]

According to the present invention, the body and the core can be obtained from the pipe material at a low manufacturing cost, and the use of the O-ring and the secondary molding of the bobbin, which have been conventionally required, can be eliminated. Therefore, the cost can be reduced and the size can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing a completed electromagnetic fuel injection valve.

FIG. 2 is an explanatory view showing a semi-finished product of an electromagnetic fuel injection valve.

FIG. 3 is a sectional view showing a core assembly.

FIG. 4 is a perspective view illustrating a bobbin.

5 is a cross-sectional view taken along the line AA of FIG.

6 is a cross-sectional view taken along the line BB of FIG.

7 is a cross-sectional view taken along the line CC of FIG.

FIG. 8 is a cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 core 2 plate 4 plate 5 bobbin half body 6 bobbin half body 8 coil 9 outer body 9a resin flow hole 10 connector 17 fuel passage

Claims (1)

[Claims] 1. A bobbin wound with a coil, a hollow core disposed inside the bobbin and having a fuel passage inside thereof, a body containing the bobbin, and a resin-molded core for electrical connection. An electromagnetic fuel injection valve including a connector, wherein the core is formed of a pipe material, and front and rear plates facing the front and rear end faces of the bobbin are attached to the core, and the bobbin connects the core between the two plates. The body is made of a pipe material, and the body is provided with a resin flow hole penetrating between both plates of the core, and when the connector is molded with resin through the flow hole. Electromagnetic fuel injection valve in which the resin is filled in the body.