JP2021148098A - Fuel injection valve - Google Patents

Abstract

To provide a fuel injection valve which is simple in a structure, and can suppress the intrusion of water from a boundary face between a housing and a resin molding.SOLUTION: A fuel injection valve includes: a valve body for opening and closing a fuel flow passage; a housing 12 for encapsulating an electromagnetic coil for driving the valve body; and a resin molding 9 for covering the electromagnetic coil at the inside of the housing 12, wherein a connector part 10 to which a drive current to the electromagnetic coil is carried at a part of the resin molding 9 is formed. The fuel injection valve comprises: a groove part 15 recessed to the inside in a radial direction so that an upper end face 12b of the housing 12 is brought into a non-contact with the resin molding 9 in a position corresponding to the connector part 10 of the resin molding 9; and a seal member 13 having a first seal upper face 13a pressed by a groove part upper face 15a of the groove part 15, and a first seal lower face 13b for sealing boundary faces 12a, 9b between the housing 12 and the resin molding 9 appearing at a groove part lower face 15c of the groove part 15.SELECTED DRAWING: Figure 6

Description

The present invention relates to a fuel injection valve used in an internal combustion engine, and more particularly to a fuel injection valve that opens and closes a fuel passage by an electromagnetically driven mover to inject fuel.

As a background technology in this technical field, there is a fuel injection valve described in Pamphlet No. 2017/212727 (Patent Document 1) of International Publication No. 2017/212727. The fuel injection valve of Patent Document 1 is a fuel injection valve provided with a valve body that opens and closes a fluid flow path, and has a tubular portion formed on the side of a fuel pipe to which the fuel injection valve is attached and a tubular portion thereof. In addition to being attached to the outer peripheral side of the portion, it is provided with a sealing member that is attached to the fuel pipe to seal between the tubular portion and the tubular portion from the external space (see summary).

Further, in the fuel injection valve of Patent Document 1, the outer periphery of the large-diameter tubular portion of the nozzle holder is covered with a resin molded body molded by an insulating resin injected from the inner circumference of the upper end opening of the housing, and the resin molded body is magnetic. The outer peripheral side of the downstream portion of the core is covered, and the tubular portion of the resin molded body is configured to cover the outer peripheral side of the magnetic core tubular portion (see paragraph 0020).

International Publication No. 2017/212727 Pamphlet

Since automobile engines are used in various environments, it is possible that the fuel injection valve attached to the automobile engine may be splashed with water depending on the environment. In the fuel injection valve of Patent Document 1, it is possible to prevent water from entering the interface between the housing and the resin molded body or the interface between the magnetic core and the resin molded body by a sealing member. Depending on the shape of the body, it is necessary to adopt a complicated structure, and there are some prisoners who find it difficult to mold the sealing member with a simple structure.

The electromagnetic coil of the fuel injection valve is located near the interface between the housing and the resin molded body, and the interface between the housing and the resin molded body is fuel when moisture enters the inside of the fuel injection valve from the outside. This is a part that easily causes malfunction of opening and closing the valve body of the injection valve.

An object of the present invention is to provide a fuel injection valve having a simple structure and capable of suppressing the ingress of water from the interface between the housing and the resin molded body.

In order to solve the above problems, the fuel injection valve of the present invention is used.
A valve body that opens and closes the fuel flow path, a housing that includes an electromagnetic coil for driving the valve body, and a resin molded body that covers the upper portion of the housing are provided, and a part of the resin molded body is said to have the same. In a fuel injection valve in which a connector portion through which a drive current to an electromagnetic coil is energized is formed.
A groove portion that is recessed inward in the radial direction at a position corresponding to the connector portion of the resin molded body and so that the upper end surface of the housing is not in contact with the resin molded body.
A seal member having a first seal upper surface pressed by the groove lower surface of the groove portion and a first seal lower surface for sealing the interface between the housing and the resin molded body is provided.

According to the present invention, it is possible to provide a fuel injection valve capable of suppressing the intrusion of water from the interface between the housing and the resin molded body into the inside with a simple structure.

Other configurations, actions, and effects of the present invention will be described in detail in the examples of the present invention shown below.

It is a figure which shows the appearance of the fuel injection valve which concerns on one Example of this invention. It is a figure which shows the appearance of the housing of the fuel injection valve which concerns on one Example of this invention, and the resin molded body. It is (a) plan view, (b) cross-sectional view (BB cross section) and (c) enlarged sectional view which shows the seal member of the fuel injection valve which concerns on one Example of this invention. It is (a) plan view and (b) cross-sectional view (BB cross section) which shows an example of the fixing member of the fuel injection valve which concerns on one Example of this invention. It is a partial cross-sectional view of the fuel injection valve which concerns on one Example of this invention. FIG. 5 is an enlarged cross-sectional view showing an enlarged partial cross section of one of the two partial cross sections of FIG. FIG. 5 is an enlarged cross-sectional view showing an enlarged view of the other partial cross section of the two partial cross sections of FIG.

Hereinafter, examples of the present invention will be described with reference to FIGS. 1 to 7.

FIG. 1 is a diagram showing the appearance of a fuel injection valve according to an embodiment of the present invention.
In the fuel injection valve 1 of this embodiment, the fuel flows from the fuel supply port 2 toward the fuel injection hole 4 through the inside of the fuel injection valve substantially along the central axis 100a. Therefore, the fuel injection valve 1 has the fuel injection hole 4 side (lower side in FIG. 1) on the downstream side and the fuel supply port 2 side (upper side in FIG. 1) on the upstream side in the direction along the central axis 1a.

The upstream end is called the base end, the lower end is called the tip, the side closer to the base end (upstream side) is the base end side, and the side closer to the tip (lower side) with respect to a certain position. ) May be referred to as the tip side for explanation. Further, in the following description, the vertical direction may be specified, but this vertical direction is based on the vertical direction of FIG. 1, and does not specify the vertical direction in the mounted state of the fuel injection valve 1.

The fuel injection valve 1 in this embodiment closes the fuel passage when the energization of the electromagnetic coil 20 is OFF, and turns on the energization of the electromagnetic coil 20 to drive a mover (not shown) by an electromagnetic attraction force to drive the fuel passage. To open and inject fuel.

As shown in FIG. 1, the nozzle holder 7 includes a small-diameter cylindrical portion 7a having a small diameter and a large-diameter tubular portion 7b having a large diameter. An orifice cup (injection hole forming member) 4 provided with a fuel injection hole 4a is inserted inside the tip portion of the small diameter tubular portion 7a, and is welded and fixed to the small diameter tubular portion 7a along the outer peripheral portion of the tip surface. NS. A conical valve seat is formed inside the orifice cup 4, and the valve body 21 contained in the nozzle holder 7 comes into contact with the valve seat to guide or block the flow of fuel to the fuel injection hole 4a. .. A groove is formed on the outer periphery of the nozzle holder 7, and a sealing member 8 represented by a resin chip seal is fitted in the groove.

A connecting member 3 with a fuel pipe provided with a fuel supply port 2 is provided at the upper end of the fuel injection valve 1, and a filter (not shown) is provided inside the fuel supply port 2. The connecting member 3 is inserted into the inner circumference of the fuel pipe (not shown). A sealing material 5 represented by an O-ring and a protective member 6 for protecting the sealing member 5 are assembled on the outer peripheral side of the connecting member 3. The seal member 5 seals the gap between the inner peripheral surface of the fuel pipe (not shown) and the outer peripheral surface 3a on the upstream side of the connecting member 3 to prevent leakage of fuel flowing through the fuel pipe.

A cup-shaped housing 12 is fixed to the outer peripheral side of the large-diameter cylindrical portion 7b of the nozzle holder 7. A through hole (not shown) is provided in the center of the bottom of the housing 12, and a large-diameter cylindrical portion 7b of the nozzle holder 7 is inserted through the through hole. The outer peripheral wall 12a of the housing 12 forms an outer peripheral yoke portion facing the outer peripheral surface of the large-diameter tubular portion 7b of the nozzle holder 7 via the electromagnetic coil 20.

An annular or cylindrical electromagnetic coil 20 is arranged in the tubular internal space formed by the housing 12. A rigid conductor (not shown) is fixed to the end of the winding start and winding end of the electromagnetic coil 20 and is drawn out from a tubular internal space formed by a metal part such as a housing. The outer circumference of the conductor and the large-diameter tubular portion 7b of the nozzle holder 7 is molded by injecting an insulating resin from the inner circumference of the upper end opening of the housing 12, and is covered with the resin molded body 9.

Further, the resin molded body 9 integrally forms a connection portion (connector portion) 10 with an engine control unit (ECU) that supplies a drive current to the electromagnetic coil 20. A current flows through the electromagnetic coil 20 by connecting the connector from the engine side to the connector portion 10 and then energizing the connector portion 10.

The resin molded body 9 is configured to cover the outer peripheral side of the magnetic core (not shown) and the outer peripheral side of the connecting member 3. The resin molded body 9 is configured to come into contact with the contact portion (lower surface) 3b formed on the connecting member 3 at the contact portion (upper surface) 9a (see FIGS. 6 and 7). This means that boundary surfaces (boundary surfaces exposed to the outside: exposed boundary surfaces) 3b and 9a are formed between the lower surface 3b of the connecting member 3 and the upper surface 9a of the resin molded body 9.

Further, the resin molded body 9 is configured to come into contact with the housing 12 at a portion located on the downstream side (tip side) with respect to the root 10a of the connector portion 10. That is, between the housing 12 and the molded resin molded body 9, the contact portion (inner peripheral surface) 12a of the housing 12 and the contact portion (outer peripheral surface) 9b of the resin molded body 9 (see FIGS. 6 and 7). ) Are in contact with the boundary surfaces 12a and 9b. In this embodiment, if the sealing member 13 is not provided on the boundary surfaces 12a and 9b, the boundary surfaces 12a and 9b form a boundary surface exposed to the outside. That is, the boundary surfaces 12a and 9b form an exposed side boundary surface.

At this time, a slight gap may be formed at the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9 or the boundary surfaces 3b and 9a between the connecting member 3 and the resin molded body 9. On the other hand, depending on the method of attaching the fuel injection valve 1 to the automobile engine or the environment around the automobile itself, moisture may be applied to the fuel injection valve 1. Alternatively, the fuel injection valve 1 itself may be flooded.

Due to the configuration of the fuel injection valve 1, the boundary surfaces 3b and 9a between the connecting member 3 and the resin molded body 9 are far from the electromagnetic coil 20, and even if water infiltrates, it is difficult to reach the electromagnetic coil 20. Therefore, it can be said that the possibility of interfering with the valve opening operation of the fuel injection valve 1 is extremely low.

However, since the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9 are close to the electromagnetic coil 20, when water enters the inside of the fuel injection valve 1, the water that has entered the inside enters the electromagnetic coil 20. Easy to reach. When water reaches the electromagnetic coil 20, a state may occur in which the valve opening operation of the fuel injection valve 1 is hindered. Further, since the internal parts of the fuel injection valve 1 such as the housing 12 and the nozzle holder 7 are made of metal, there is a possibility that moisture may cause corrosion of these metal parts.

Therefore, in this embodiment, even if there is a gap between the housing 12 and the resin molded body 9 when water is directly applied to the fuel injection valve 1 or the fuel injection valve 1 itself is submerged, the housing Prevents water from entering the inside from between the 12 and the resin molded body 9. Therefore, the seal member 13 shown in FIG. 1 is provided on the downstream side of the connector portion 10 of the resin molded body 9 and on the upstream end surface 12a of the housing 12, and the upper end surface 14a is a fuel pipe on the upstream side of the seal member 13. In order to contact the downstream end surface (not shown) or the member (not shown) that fills the space with the fuel pipe, the lower end surface 14b contacts the seal member 13, and the fuel injection valve 1 is fixed to the engine. A fixing member 14 for transmitting a force in the tip direction to the fuel injection valve 1 is provided.

Here, the configuration of the fuel injection valve 1 of this embodiment will be described in more detail with reference to FIGS. 2 to 5.

FIG. 2 is a diagram showing the appearance of a fuel injection valve housing and a resin molded body according to an embodiment of the present invention.

A groove portion 15 recessed toward the central axis 1a (inward in the radial direction) of the fuel injection valve 1 is formed in the lower portion (tip side) 11 of the connector portion 10 provided in the resin molded body 9. The groove portion 15 has a groove portion upper surface 15a, a groove portion outer peripheral surface 15b, and a groove portion lower surface 15c. The groove portion upper surface 15a is formed on the resin molded body 9 so that the upstream end surface 12b of the housing 12 is exposed, and constitutes the upstream side surface of the groove portion 15. The groove portion outer peripheral surface 15b is a portion corresponding to the bottom surface of the groove portion 15 that is recessed inward in the radial direction, and constitutes an outer peripheral surface having a diameter smaller than the outer diameter φ12 of the housing 12. The groove portion lower surface 15c constitutes a surface on the downstream side (tip side) of the groove portion 15 in which the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9 exist (appear). The upstream end surface (upper end surface) 12b of the housing 12 forms a part of the groove lower surface 15c, and the groove lower surface 15c is formed of the upstream end surface 12b of the housing 12 and the resin molded body 9. In this case, the portion of the lower surface 15c of the groove portion formed by the upstream end surface 12b of the housing 12 is located radially outward with respect to the portion formed by the resin molded body 9.

The boundary surfaces 12a and 9b extend from the lower surface 015c of the groove portion in the direction along the central axis 1a toward the tip end side.

In the resin molded body 9, the outer peripheral surface 15b of the groove portion and the lower surface 15c of the groove portion extend from the groove portion 15 in a portion separated from the lower portion (tip side) 11 of the connector portion 10 in the circumferential direction. That is, the groove portion outer peripheral surface 15b and the groove portion lower surface 15c are formed over the entire circumference. In this case, the groove portion upper surface 15a does not exist in the portion separated from the lower portion (tip side) 11 of the connector portion 10, and the groove portion outer peripheral surface 15b has a diameter smaller than the outer diameter φ12 of the housing 12 and is on the outer peripheral surface of the housing 12. On the other hand, a stepped outer peripheral surface (stepped outer peripheral surface) is formed, and the groove portion lower surface 15c constitutes a stepped surface between the stepped outer peripheral surface 15b and the outer peripheral surface of the housing 12.

The resin molded body 9 has a receiving surface 16 of the fixing member 14 on the upper side (base end side, opposite to the housing 12) of the stepped outer peripheral surface 15b, and an outer peripheral surface 16a formed on the upper side (base end side) thereof. And have. The outer peripheral surface 16a has a smaller diameter (φ16a <φ15b) than the outer diameter φ15b of the stepped outer peripheral surface 15b, and constitutes a stepped outer peripheral surface (stepped outer peripheral surface) with respect to the stepped outer peripheral surface 15b. The receiving surface 16 constitutes a stepped surface between the stepped outer peripheral surface (receiving portion outer peripheral surface) 16a and the stepped outer peripheral surface 15b. The stepped outer peripheral surface 16a and the receiving surface 16 are separated by the connector portion 10 and are not formed on the lower portion 11 of the connector portion 10.

Next, the seal member 13 of the fuel injection valve 1 in this embodiment will be described with reference to FIG. FIG. 3 is a plan view (a), a cross-sectional view (BB cross section), and an enlarged cross-sectional view (c) showing a seal member of a fuel injection valve according to an embodiment of the present invention.

The seal member 13 is configured as an annular member, and is pressed by the groove portion 15 of the resin molded body 9, the upper surface 13a of the first seal portion and the lower surface 13b of the first seal portion, and the upper surface of the second seal portion pressed by the fixing member 14. It is composed of 13c and the lower surface 13d of the second seal portion, and further, an inner peripheral surface 13e and an outer peripheral surface 13f of the seal member 13.

In this embodiment, the upper surface 13a of the first seal portion and the lower surface 13b of the first seal portion are portions located in the groove portion 15, and the upper surface 13c of the second seal portion and the lower surface 13d of the second seal portion are fixed members separated from the groove portion 15. It is a part located in the part where 14 is provided. When the seal member 13 is viewed alone, there is no difference or boundary between the upper surface 13a of the first seal portion and the lower surface 13b of the first seal portion and the upper surface 13c of the second seal portion and the lower surface 13d of the second seal portion. It is configured as one annular member having a uniform shape in the direction.

The upper surface 13a of the first seal portion and the upper surface 13c of the second seal portion are respectively formed of a plane, and these planes 13a and 13c are formed as the same plane. On the other hand, the lower surface 13b of the first seal portion and the lower surface 13d of the second seal portion are each composed of curved surfaces (curved surfaces) having a curvature. In this case, the curved surfaces of the lower surface 13b of the first seal portion and the lower surface 13d of the second seal portion are curved surfaces that are convex downward (tip side or housing 12 side).

Next, the fixing member 14 of the fuel injection valve 1 in this embodiment will be described with reference to FIG. FIG. 4 is a plan view (a) and a cross-sectional view (BB cross section) showing an example of a fixing member of a fuel injection valve according to an embodiment of the present invention.

In addition to the upper end portion 14a and the lower end portion 14b, the fixing member 14 includes a notch portion 14c through which the connector portion 10 of the resin molded body 9 passes, an inner peripheral surface 14d, and an outer peripheral surface 14f. That is, the fixing member 14 has a shape (arc shape) in which a part of the annular member in the circumferential direction is cut out.
The form of the fixing member 14 is not limited to the embodiment, and includes various modifications within a range that does not deviate from the gist thereof. For example, in this embodiment, a bendable portion (flexible portion) 14 g is provided in a part of the fixing member 14 in the direction (axial direction) along the central axis 1a, and such a flexible portion 14 g is provided. It may not be in the form. The fixing member 14 of this embodiment has a shape in which the upper arc-shaped portion 14A and the lower arc-shaped portion 14B are connected by a bending portion 14g. The upper end portion 14a of the upper arc-shaped portion 14A abuts on the cylindrical portion of the fuel pipe, and the lower end portion 14b of the lower arc-shaped portion 14B abuts on the receiving surface 16 of the fuel injection valve 1. When the fuel injection valve 1 is attached to the engine head, for example, the flexible portion 14g absorbs the gap error between the engine head and the tubular portion of the fuel pipe, and presses the fuel injection valve 1 against the engine head (mounting portion). Occurs.

Next, an embodiment of the seal structure according to the present invention will be described with reference to FIGS. 5 to 7.

FIG. 5 is a partial cross-sectional view of a fuel injection valve according to an embodiment of the present invention. FIG. 6 is an enlarged cross-sectional view showing an enlarged partial cross section of one of the two partial cross sections of FIG. FIG. 7 is an enlarged cross-sectional view showing the other partial cross section of the two partial cross sections of FIG. 5 in an enlarged manner.

FIG. 6 shows an enlarged view of the VI portion of FIG. 5, and shows a cross section of a position corresponding to the groove portion 15 of the resin molded body 9. FIG. 7 is an enlarged view of the VII portion of FIG. 5, and shows a cross section of a position corresponding to a position other than the groove portion 15. At the position shown in FIG. 7, the seal member 13 is fixed to the fuel injection valve 1 by the fixing member 14. That is, at the position shown in FIG. 7, the seal member 13 is sandwiched between the groove portion lower surface 15c of the groove portion 15 and the lower end portion 14b of the fixing member 14.

The seal member 13 is assembled to the groove 15 of the resin molded body 9 in such a manner that the upper surface 15a of the groove and the upper surface 13a of the first seal of the seal member 13 correspond to each other, and the lower surface 15c of the groove and the lower surface 13b of the first seal correspond to each other. The seal member 013 is pressed against the groove 15, and surface pressure is generated on the upper surface 13a of the first seal and the lower surface 13b of the first seal to seal the interface 12a and 9b between the housing 12 and the resin molded body 9. do.

That is, the fuel injection valve 1 in this embodiment includes a valve body 21 that opens and closes the fuel flow path, a housing 12 that includes an electromagnetic coil 20 for driving the valve body 21, and the electromagnetic wave inside the housing 12. In a fuel injection valve including a resin molded body 9 that covers at least a part of the coil, and a connector portion 10 is formed in a part of the resin molded body 9 to which a driving current to the electromagnetic coil 20 is applied. A groove portion 15 that is recessed inward in the radial direction so that the upper end surface 12b of the housing 12 is not in contact with the resin molded body 9 at a position corresponding to the connector portion 10 of the 9 and is pressed by the groove portion upper surface 15a of the groove portion 15. 1 The seal member 13 having a first seal lower surface 13b for sealing the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9 appearing on the seal upper surface 13a and the groove lower surface 15c of the groove portion 15 is provided.

As a result, the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9 can be sealed by the sealing member 13 having a simple structure, and water intrusion from the boundary surfaces 12a and 9b in the groove portion 15 can be suppressed. As for the assembly of the seal member 13, since the seal member 13 is composed of a stretchable member such as rubber, it can be easily assembled because it is only fitted in the groove portion 15. Further, by providing the groove portion 15 as in this embodiment, it is possible to easily obtain the same effect as in this embodiment even when the shape of the resin molded body 9 is changed.

At a position (position shown in FIG. 7) other than the groove portion 15, the seal member 13 corresponds to the lower end portion 14b of the fixing member 14 and the second seal upper surface 13c of the seal member 13, and corresponds to the upper end surface 12b of the housing 12. The second seal lower surface 13d of the seal member 13 is assembled in a corresponding manner, the seal member 13 is pressed by the fixing member 14, surface pressure is generated on the second seal lower surface 13d, and the housing 12 and resin molding are performed. The interface 12a and 9b with the body 9 are sealed.

That is, in the fuel injection valve 1 of the present embodiment, the seal member 13 is pressed by the fixing member 14 different from the resin molded body 9 at a position different from the connector portion 10 of the resin molded body 9 in the circumferential direction. It has a second seal upper surface 13c and a second seal lower surface 13d that comes into contact with the upper end surface 12b of the housing 12 and seals the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9.

As a result, even at a position other than the connector portion 10 of the resin molded body 9, an appropriate surface pressure is generated on the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9, and the housing 12 and the resin molded body 9 are brought into contact with each other. It is possible to prevent or suppress the infiltration of water into the boundary surfaces 12a and 9b.

Here, it is desirable that the diameter (inner diameter) φ13e of the inner peripheral surface 13e of the seal member 13 is smaller than the diameter (outer diameter) φ15b of the outer peripheral surface 015b of the groove portion 15 with which the inner peripheral surface 13e of the seal member 13 abuts.

That is, in the fuel injection valve 1 of this embodiment, it is desirable that the inner peripheral side surface of the seal member 13 is formed of a diameter φ13e smaller than the diameter φ15b of the groove portion outer peripheral surface 15b of the resin molded body 9.

As a result, a surface pressure is generated between the inner peripheral surface 13e of the seal member 13 and the outer peripheral surface 15b of the groove portion of the resin molded body 9, and the moisture on the boundary surfaces 12a and 9b between the housing 12 and the resin molded body 9 is generated. It is possible to prevent or suppress the arrival.

Further, in the resin molded body 9, a receiving surface (step portion) that receives a part of the lower end surface 14b of the fixing member 14 at a position where the height h15 of the groove portion outer peripheral surface 15b is smaller than the axial thickness t13 of the sealing member 13. 16 is provided. The diameter φ16a of the receiving portion outer peripheral surface 16a of the fixing member 14 is smaller than the diameter (inner diameter) φ14d (see FIG. 4) of the inner peripheral surface 14d of the fixing member 14. As a result, the lower end surface 14b of the fixing member 14 can be reliably brought into contact with the receiving surface 16, the pressing force is surely applied to the sealing member 13, and the pressing force or the amount of compression does not become too large. Can be restricted as such.

That is, in the fuel injection valve 1 of this embodiment, a step portion 16 for regulating the amount of compression of the seal member 13 is provided on the outer peripheral surface of the resin molded body 9.

This prevents the seal member 13 from being over-compressed, and by maintaining an appropriate amount of compression, it is possible to secure an appropriate surface pressure.

Further, as described above, the upper surface 13a of the first seal and the upper surface 13c of the second seal are respectively configured on the same plane, and the lower surface 13b of the first seal and the lower surface 13d of the second seal are each composed of the same curved surface having a curvature. ..

That is, in the fuel injection valve 1 of the present embodiment, when the seal member 13 is alone, the first seal upper surface 13a and the second seal upper surface 13c are formed of a flat surface, and the first seal lower surface 13b and the second seal lower surface 13d are formed. It is composed of curved surfaces with curvature.

Since the first seal upper surface 13a and the second seal upper surface 13c are formed of a flat surface, the pressure received by the seal member 13 can be appropriately transmitted to the first seal lower surface 13b and the second seal lower surface 13d.

Since the lower surface 13b of the first seal and the lower surface 13d of the second seal are formed of curved surfaces, the lower surfaces 13b and 13d of the seal positively come into contact with the interface surfaces 12a and 9b between the housing 12 and the resin molded body 9. As a result, the surface pressure generated on the contact surface is increased as compared with the state where the shape of the contact portion is not convex, and it is possible to perform sealing more efficiently.

Further, the seal member 13 has heat resistance, water resistance, and oil resistance in terms of the usage environment, and is made of an extendable material, particularly a rubber material, in consideration of workability when assembling to the fuel injection valve 1. It is desirable to be done.

That is, in the fuel injection valve 1 of this embodiment, it is desirable that the seal member 13 is integrally made of a rubber material (silicon or fluorine).

As a result, proper sealing performance can be realized even in an environment where the fuel injection valve is used, such as a temperature environment in which the fuel injection valve is exposed to moisture containing a corrosive component or the temperature changes at 120 ° C. or the like.

Further, it is desirable that the lower end surface 14b of the fixing member 14 is also formed of a uniform flat surface.

That is, in the fuel injection valve 1 of this embodiment, it is desirable that the surface of the fixing member 14 in contact with the second seal upper surface 13c of the seal member 13 is a uniform flat surface.

As a result, the fixing member 14 evenly contacts the upper surface 13c of the second seal of the seal member 13 to equalize the surface pressure generated between the lower surface 13d of the second seal and the upstream end surface 12a of the housing 12. Therefore, it is possible to prevent or suppress the arrival of moisture on the interface 12a and 9b between the housing 12 and the resin molded body 9.

The present invention is not limited to the above-described examples, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the configurations. Further, it is possible to add another configuration or replace a part of the configuration of the embodiment with another configuration.

1 ... Fuel injection valve, 9 ... Resin molded body, 10 ... Connector part, 12 ... Housing, 12b ... Upper end surface of housing 12, 12a, 9b ... Boundary surface between housing 12 and resin molded body 9, 13 ... Seal member, 13a ... 1st seal upper surface, 13b ... 1st seal lower surface, 13c ... 2nd seal upper surface, 13d ... 2nd seal lower surface, 14 ... fixing member, 15 ... groove, 15a ... groove upper surface, 15c ... groove lower surface, 16 ... seal A step portion that regulates the amount of compression of the member 13, 20 ... an electromagnetic coil, 21 ... a valve body.

Claims (6)

The resin molded body includes a valve body that opens and closes the fuel flow path, a housing that includes an electromagnetic coil for driving the valve body, and a resin molded body that covers the electromagnetic coil inside the housing. In a fuel injection valve in which a connector portion through which a drive current to the electromagnetic coil is energized is formed in a part thereof.
A groove portion that is recessed inward in the radial direction at a position corresponding to the connector portion of the resin molded body and so that the upper end surface of the housing is not in contact with the resin molded body.
A fuel injection valve comprising a seal member having a first seal upper surface pressed by the groove lower surface of the groove portion and a first seal lower surface for sealing a boundary surface between the housing and the resin molded body. In the fuel injection valve according to claim 1,
The seal member comes into contact with the upper surface of the second seal pressed by a fixing member different from the resin molded body and the upper end surface of the housing at a position different from the connector portion of the resin molded body in the circumferential direction. A fuel injection valve having a second seal lower surface that seals a boundary surface between the housing and the resin molded body. In the fuel injection valve according to claim 1 or 2.
A fuel injection valve in which the diameter of the inner peripheral surface of the seal member is smaller than the diameter of the outer peripheral surface of the groove with which the inner peripheral surface of the seal member abuts. In the fuel injection valve according to claim 1 or 2.
A fuel injection valve provided with a stepped portion that regulates the amount of compression of the seal member on the outer peripheral surface of the resin molded body. In the fuel injection valve according to claim 2,
The seal member is characterized in that the upper surface of the first seal and the upper surface of the second seal are formed of a flat surface, and the lower surface of the first seal and the lower surface of the second seal are formed of a curved surface having a curvature. In the fuel injection valve according to claim 2,
A fuel injection valve in which the surface of the fixing member in contact with the upper surface of the second seal of the seal member is a uniform flat surface.

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