JP2009174399A - Fuel injection valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel injection valve excellent in reliability and for inhibiting drop of fuel injection quantity characteristics of fuel during use. <P>SOLUTION: An injector (fuel injection valve) 1 includes a pipe (storage member) 10, a fixed core 21 provided at an inner circumference side of a coil and pipe 10, a movable core 22 provided with opposing to the fixed core 21 in an axial direction, and a needle (valve member) opening and closing injection holes injecting fuel, and forms a fuel passage 6 providing communication between an upstream side of the fixed core 21 and a downstream side of the movable core 22. An arc surface 111 along outer circumference surfaces 212, 222 of the fixed core 21 and the movable core 22, and a plurality of grooves 112 indented outward from the arc surface 111 are formed on an inner circumference surface 11 of the pipe 10. A groove fuel passage 64 constructing a part of a fuel passage 6 is formed between the groove 112 of the pipe 10 and the outer circumference surfaces 212, 222 of the fixed core 21 and the movable core 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel injection valve that injects and supplies fuel to an internal combustion engine or the like.

2. Description of the Related Art Conventionally, a fuel injection valve that injects and supplies fuel to an internal combustion engine or the like is known (see Patent Document 1).
The fuel injection valve is fixed to, for example, a cylindrical housing member, a coil disposed on the outer circumferential side of the housing member, a fixed core disposed on the inner circumferential side of the housing member, and an inner circumferential side of the housing member Some have a movable core disposed opposite to the core in the axial direction, and a valve member that moves in the axial direction together with the movable core and opens and closes an injection hole for injecting fuel. The fuel injection valve includes, in the housing member, a fuel passage that includes the inside of the fixed core, the inside and outside of the valve member, and communicates the upstream side of the fixed core and the downstream side of the movable core.

JP 2006-57572 A

However, the fuel injection valve having the above structure has the following problems.
That is, when the fuel injection valve is used, the temperature of the coil rises due to heat generated by energization or heat received from the internal combustion engine. As the coil temperature increases, the resistance increases and the current value decreases. Therefore, the magnetic attractive force generated between the fixed core and the movable core is reduced, and the responsiveness of the valve member is deteriorated. This has caused a problem that the injection amount characteristic is deteriorated. Further, when the temperature of the fuel injection valve becomes high, vapor (air) is generated in the fuel, and the vapor accumulates on the downstream side of the fuel passage, resulting in a problem that the injection amount characteristic is deteriorated.

  The present invention has been made in view of such conventional problems, and is intended to provide a highly reliable fuel injection valve that can suppress a decrease in fuel injection amount characteristics during use. .

The present invention includes a cylindrical housing member made of a magnetic material, a coil disposed on the outer peripheral side of the housing member, a fixed core made of a magnetic material disposed on the inner peripheral side of the housing member, From a magnetic material that is arranged on the inner peripheral side of the housing member so as to face the fixed core in the axial direction and is attracted to the fixed core by a magnetic attractive force generated between the fixed core and the energization of the coil. And a valve member that moves in the axial direction together with the movable core and opens and closes a nozzle hole for injecting fuel, and the upstream side of the fixed core and the downstream side of the movable core in the housing member A fuel injection valve formed with a fuel passage communicating with
On the inner peripheral surface of the housing member, there are an arc surface having an arc-shaped surface along the outer peripheral surface of the fixed core and the movable core, and one or a plurality of concave grooves recessed outward from the arc surface. Formed,
A groove fuel passage constituting a part of the fuel passage is formed between the concave groove on the inner peripheral surface of the housing member and the outer peripheral surface of at least one of the fixed core and the movable core. The fuel injection valve is characterized in that (Claim 1).

  The fuel injection valve according to the present invention includes an upstream side of the fixed core and the movable core between the concave groove on the inner peripheral surface of the housing member and the outer peripheral surface of at least one of the fixed core and the movable core. And a groove fuel passage that constitutes a part of the fuel passage communicating with the downstream side. By providing the groove fuel passage, the fuel injection valve becomes hot and the vapor (air) in the generated fuel easily escapes to the upstream side of the fuel passage. For this reason, it is possible to suppress the vapor from being accumulated on the downstream side of the fuel passage and the deterioration of the injection amount characteristic.

  In the present invention, the groove fuel passage is provided outside the arc surface on the inner peripheral surface of the housing member. That is, the groove fuel passage is provided at a position closer to the coil disposed on the outer peripheral side of the housing member. Therefore, the coil can be cooled by the fuel flowing through the groove fuel passage, and the temperature rise of the coil can be suppressed. As a result, it is possible to avoid a problem that has conventionally occurred due to a rise in the temperature of the coil, and to suppress a decrease in the injection amount characteristic.

The fixed core is usually press-fitted and fixed to the inner peripheral side of the housing member. Therefore, when the groove fuel passage is provided between the concave groove of the housing member and the outer peripheral surface of the fixed core, the contact area between the housing member and the fixed core can be reduced. Thereby, the effect that an assembly | attachment can be made easy by reduction of the press-fit load in the said fixed core etc. is also acquired.
Further, even if the housing member is thin, it can be formed into a rib shape by making the outer peripheral surface of the housing member protrude outward as described later, and the rigidity of the housing member is increased. Highly accurate assembly is possible.

  Thus, according to the present invention, it is possible to provide a fuel injection valve that can suppress a decrease in fuel injection amount characteristics during use and that is excellent in reliability.

  In the present invention, when the fuel injection valve is energized to the coil, a magnetic field is generated in the magnetic circuit formed in the housing member, the fixed core, the movable core and the like made of a magnetic material by the magnetic field generated by the coil. A magnetic attraction force is generated between the movable core and the fixed core. The movable core is attracted to the fixed core by the magnetic attractive force generated between the movable core and the fixed core, and the valve member is moved accordingly, and fuel is injected from the injection hole. It is configured.

Preferably, the groove fuel passage is formed between the concave groove on the inner peripheral surface of the housing member and the outer peripheral surfaces of both the fixed core and the movable core.
In this case, the groove fuel passage communicates between the upstream side of the fixed core and the downstream side of the movable core through a route that continuously passes through the outer peripheral surface of the fixed core and the outer peripheral surface of the movable core. It becomes a passage to do. For this reason, the vapor in the fuel becomes easier to escape to the upstream side of the fuel passage.

  As described above, the groove fuel passage is preferably provided between the concave groove and the outer peripheral surfaces of both the fixed core and the movable core. However, the outer periphery of the concave groove and the fixed core is preferable. It can also be set as the structure provided only between a surface, or only between the said ditch | groove and the outer peripheral surface of the said movable core.

  Further, as described above, the groove fuel passage serves as a passage communicating between the upstream side of the fixed core and the downstream side of the movable core. Therefore, unlike the prior art, it is not necessary to provide the fuel passage inside the fixed core and the movable core. That is, the fuel passage in the portion where the fixed core and the movable core are disposed in the housing member can be secured by the groove fuel passage. As a result, the processing that has been performed to form the fuel passage in the fixed core and the movable core can be eliminated, and the productivity can be improved and the cost can be reduced.

In addition, a magnetic circuit forming member that forms a magnetic circuit together with the housing member and the fixed core by energizing the coil is disposed on the outer peripheral surface of the housing member that houses the stationary core. ,
The groove fuel passage is preferably formed at a position that does not face the magnetic circuit forming member via the housing member.
In this case, the fixed fuel core, the housing member, and the magnetic circuit forming member adjacent to each other are prevented by disposing the groove fuel passage and the magnetic circuit forming member at positions opposed to each other via the housing member. Magnetic loss can be suppressed in the magnetic circuit formed by the above. As a result, the effect obtained by providing the groove fuel passage can be obtained while sufficiently securing the magnetic characteristics.

Further, the positions and the number of the concave grooves and the groove fuel passages can be changed according to the use situation or the like.
Various shapes can be adopted for the shape of the groove and the groove fuel passage. For example, it can be provided linearly in the axial direction or can be provided spirally.

Moreover, it is preferable that the said accommodating member has a protrusion part which makes this outer peripheral surface protrude outward in the outer peripheral surface corresponding to the part in which the said groove is formed.
In this case, the protruding portion of the housing member can be formed in a rib shape. For this reason, the rigidity of the housing member can be increased, and high-precision assembly is possible.

  In addition, since the protrusion is formed on the outer peripheral surface of the housing member, a step is generated on the outer peripheral surface of the housing member. Therefore, the member to be assembled to the housing member can be positioned using the step. it can. For example, by using the end surface in the axial direction of the protruding portion as a contact surface (seat) of a member to be assembled with the housing member, the member can be easily positioned and the assembly can be performed with high accuracy.

  Moreover, the said recessed groove in the internal peripheral surface of the said accommodating member can be formed by denting an internal peripheral surface by deform | transforming outward a part of said accommodating member by press work etc., for example. At this time, the projecting portion formed by projecting the outer peripheral surface outward is formed on the outer peripheral surface of the housing member.

And the structure which provides the above protrusion parts is especially effective when the said accommodating member is a thin type with comparatively small thickness. For example, it is effective when the thickness of the housing member is 0.1 to 0.3 mm.
In the thin-type accommodation member, it is necessary to ensure sufficient rigidity for the assembly of the fixed core. Therefore, it is preferable to form the concave groove by press working or the like to increase the rigidity.
In addition, when the thickness of the housing member is less than 0.1 mm, the rigidity of the housing member cannot be sufficiently ensured even when the protruding portion is provided, and the housing member does not have the rigidity. Assembling of the fixed core may be difficult.

In addition, since the housing member of a thick type in which the thickness of the housing member exceeds 0.3 mm can sufficiently ensure rigidity, the concave groove may be formed by pressing or the like. The inner peripheral surface may be formed by cutting or the like without deforming the member.
In addition, when the thickness of the said accommodating member exceeds 0.7 mm, since the magnetic flux which flows into the said accommodating member increases and the flow of the magnetic flux to the said movable core reduces, there exists a possibility that a magnetic characteristic may fall.

Example 1
A fuel injection valve (hereinafter referred to as an injector) according to an embodiment of the present invention will be described with reference to FIGS.
The injector 1 of this example is applied to, for example, a port injection type gasoline engine, as shown in FIG. The injector 1 is mounted on an engine head (not shown). The injector 1 is not limited to a port injection type gasoline engine, but may be applied to a direct injection type gasoline engine or the like.
Moreover, in the injector 1 of this example, let the side in which the injection hole 34 is provided be a front end side (downstream side regarding fuel), and let the opposite side be a rear end side (upstream side).

As shown in FIG. 1, the injector 1 includes a cylindrical pipe (accommodating member) 10. The pipe 10 is made of a magnetic material. The pipe 10 is of a thin type having a thickness of 0.1 to 0.3 mm.
A fixed core 21 is accommodated on the inner peripheral side of the pipe 10 by press-fitting. The fixed core 21 is formed in a cylindrical shape from a magnetic material. An adjusting pipe 28 and a spring 26 described later are accommodated on the inner peripheral side of the fixed core 21.

A fuel inlet 191 is formed at the opening end of the rear end portion 102 of the pipe 10. Fuel is supplied to the fuel inlet 191 from a fuel tank by a fuel pump (not shown).
Further, a filter member 18 for removing foreign matters contained in the fuel is disposed on the inner peripheral side of the rear end portion 102 of the pipe 10.

A nozzle body 31 is accommodated in the tip 101 of the pipe 10. The nozzle body 31 is formed in a cylindrical shape, and is fixed to the tip portion 101 of the pipe 10 by, for example, press fitting, welding, or the like.
The nozzle body 31 has a valve seat 32 on a conical inner wall surface whose inner diameter decreases as it approaches the tip. A nozzle hole plate 33 is disposed at the tip 311 of the nozzle body 31. In addition, the nozzle hole 34 is formed in the nozzle hole plate 33. The injection hole 34 is provided so that the inner side and the outer side of the injection hole plate 33 communicate with each other. The nozzle hole 34 may be either single or plural.

A movable core 22 is accommodated on the inner peripheral side of the pipe 10. The movable core 22 is formed in a cylindrical shape from a magnetic material. The movable core 22 can reciprocate in the axial direction on the inner peripheral side of the pipe 10.
A needle (valve member) 40 is accommodated on the inner peripheral side of the pipe 10 and the nozzle body 31 so as to be reciprocally movable in the axial direction. The needle 40 is disposed coaxially with the nozzle body 31. The needle 40 has a rear end joined to the movable core 22. Therefore, the movable core 22 and the needle 40 can reciprocate in the axial direction integrally. The needle 40 has a seal portion 42 at the tip. The seal portion 42 can be seated on the valve seat 32 of the nozzle body 31.

  The needle 40 is in contact with the spring 26 that is an elastic member at the rear end. One end portion of the spring 26 is in contact with the rear end portion of the needle 40, and the other end portion is in contact with the adjusting pipe 28. The elastic member is not limited to a spring, and for example, a leaf spring or a gas or liquid damper can be applied.

  Further, as shown in the figure, the adjusting pipe 28 is press-fitted into the inner peripheral side of the fixed core 21 as described above. By adjusting the press-fitting amount of the adjusting pipe 28, the load of the spring 26 is adjusted. The spring 26 has a force that extends in the axial direction. Therefore, the integral needle 40 and the movable core 22 are pressed by the spring 26 in the direction in which the seal portion 42 is seated on the valve seat 32.

Further, as shown in the figure, a coil 51 is disposed on the outer peripheral side of the pipe 10. The coil 51 is wound around a spool 52 formed in a cylindrical shape made of resin. The coil 51 is covered with a coil resin mold 53 made of resin.
A housing holder 14 is disposed on the distal end side and the outer peripheral side of the coil 51. A housing plate (magnetic circuit forming member) 15 is disposed on the rear end side of the coil 51. The housing plate 15 is disposed adjacent to the outer peripheral side of the portion of the pipe 10 that houses the fixed core 21. The coil 51 is held on the outer peripheral side of the pipe 10 by the housing holder 14 and the housing plate 15.

The pipe 10, the housing holder 14, and the housing plate 15 are covered with a resin mold 54 made of resin. The coil 51 is connected to the terminal 57 of the electrical connector 56 by the wiring member 55. The electrical connector 56 is formed integrally with the resin mold 54.
The housing holder 14 and the housing plate 15 are formed in a cylindrical shape from a magnetic material, and form a magnetic circuit together with the pipe 10, the movable core 22 and the fixed core 21 by energizing the coil 51.

As shown in the figure, the injector 1 has a fuel passage 6 in the pipe 10 that communicates the upstream side of the fixed core 21 and the downstream side of the movable core 22.
In this example, the fuel passage 6 includes an upstream fuel passage 61 on the upstream side of the fixed core 21, an inner peripheral side of the adjusting pipe 28, an inner peripheral side of the fixed core 21, an inner peripheral side of the movable core 22, and a needle. 40, a normal fuel passage 62 formed in communication with the inside of the motor 40, and a downstream fuel passage 63 formed on the downstream side of the movable core 22 and formed between the needle 40 and the nozzle body 31.

  And in this example, as shown to Fig.3 (a)-(c), the outer peripheral surface 212 of the fixed core 21 arrange | positioned by the inner peripheral surface 11 of the cylindrical pipe 10 at the inner peripheral side of the pipe 10 is shown. And the circular arc surface 111 which has the circular arc-shaped surface along the outer peripheral surface 222 of the movable core 22, and the ditch | groove 112 dented outward from the circular arc surface 111 are formed. The concave groove 112 is provided at two locations in a straight line in the axial direction in the portion of the pipe 10 that accommodates the fixed core 21 and the movable core 22.

Moreover, as shown in the figure, the pipe 10 has a projecting portion 121 formed by projecting the outer peripheral surface 12 outward on the outer peripheral surface 12 corresponding to the portion where the concave groove 112 is formed.
In this example, a part of the pipe 10 is deformed outward by pressing to form the concave groove 112 by denting the inner peripheral surface 11, and at the same time, a protrusion 121 is formed on the outer peripheral surface 12 of the pipe 10. is there.

Further, as shown in FIG. 2, a part of the fuel passage 6 is formed between the concave groove 112 on the inner peripheral surface 11 of the pipe 10, the outer peripheral surface 212 of the fixed core 21, and the outer peripheral surface 222 of the movable core 22. A groove fuel passage 64 is formed. That is, the injector 1 of this example has a groove fuel passage 64 as the fuel passage 6 in addition to the upstream fuel passage 61, the normal fuel passage 62, and the downstream fuel passage 63. The groove fuel passage 64 is formed at a position not facing the housing plate 15 via the pipe 10.
Further, as shown in FIG. 1, the groove fuel passage 64 is provided so as to communicate between the upstream fuel passage 61 and the downstream fuel passage 63.

  In this example, FIG. 2 is a view showing a cross section taken along line AA of FIG. 1, but the coil 51, the spool 52, the coil resin mold 53, the resin mold 54, and the like are omitted. The same applies to FIG. 5, FIG. 6, FIG. 8, and FIG.

Next, the operation of the injector 1 having the above configuration will be described.
When energization of the coil 51 is stopped, no magnetic attractive force is generated between the fixed core 21 and the movable core 22. Therefore, the movable core 22 is separated from the fixed core 21 by the pressing force of the spring 26. As a result, when energization to the coil 51 is stopped, the seal portion 42 of the needle 40 is seated on the valve seat 32 (valve closed state). Therefore, fuel is not injected from the injection hole 34.

  When the coil 51 is energized, magnetic flux flows through the magnetic circuit formed in the housing holder 14, the pipe 10, the movable core 22, the fixed core 21, and the housing plate 15 due to the magnetic field generated in the coil 51. Therefore, a magnetic attractive force is generated between the fixed core 21 and the movable core 22 that are separated from each other. Thereby, when the magnetic attraction force generated between the fixed core 21 and the movable core 22 becomes larger than the pressing force of the spring 26, the integral movable core 22 and the needle 40 move in the direction of the fixed core 21. As a result, the seal portion 42 of the needle 40 is separated from the valve seat 32 (valve open state).

  The fuel flowing in from the fuel inlet 191 of the pipe 10 flows from the fuel hole 45 to the downstream fuel passage 63 outside the needle 40 through the filter member 18, the upstream fuel passage 61, and the normal fuel passage 62. In this example, the fuel flows from the upstream fuel passage 61 to the downstream fuel passage 63 via the groove fuel passage 64. Then, the fuel that has flowed into the downstream fuel passage 63 is injected from the nozzle hole 34 of the nozzle hole plate 33 via the space between the needle 40 separated from the valve seat 32 and the nozzle body 31.

  When energization of the coil 51 is stopped, the magnetic attractive force between the fixed core 21 and the movable core 22 disappears. Thereby, the integral movable core 22 and the needle 40 are moved in the opposite direction to the fixed core 21 by the pressing force of the spring 26. As a result, the seal portion 42 of the needle 40 is again seated on the valve seat 32 (closed state). Therefore, the fuel injection from the nozzle hole 34 is completed.

Next, the function and effect of the injector (fuel injection valve) 1 of this example will be described.
The injector 1 of this example includes an upstream side of the fixed core 21 between the concave groove 112 in the inner peripheral surface 11 of the pipe 10 and at least one of the outer peripheral surface 212 of the fixed core 21 and the outer peripheral surface 222 of the movable core 21. A groove fuel passage 64 constituting a part of the fuel passage 6 communicating with the downstream side of the movable core 22 is provided. By providing the groove fuel passage 64, the vapor (air) in the fuel generated when the injector 1 becomes hot becomes easy to escape to the upstream side of the fuel passage 6. Therefore, it is possible to suppress the vapor from being accumulated on the downstream side of the fuel passage 6 and the deterioration of the injection amount characteristic.

  In this example, the groove fuel passage 64 is provided outside the arc surface 111 on the inner peripheral surface 11 of the pipe 10. That is, the groove fuel passage 64 is provided at a position closer to the coil 51 disposed on the outer peripheral side of the pipe 10. Therefore, the coil 51 can be cooled by the fuel flowing through the groove fuel passage 64, and the temperature rise of the coil 51 can be suppressed. Thereby, the problem which has conventionally occurred due to the temperature rise of the coil 51 can be avoided, and the deterioration of the injection amount characteristic can be suppressed.

Further, the fixed core 21 is usually fixed by being press-fitted into the inner peripheral side of the pipe 10. Therefore, when the groove fuel passage 64 is provided between the concave groove 112 of the pipe 10 and the outer peripheral surface 222 of the fixed core 22 as in this example, the contact area between the pipe 10 and the fixed core 21 is reduced. be able to. Thereby, the press-fit load in the fixed core 21 can be reduced, and the fixed core 21 can be assembled with high accuracy.
Moreover, even if it is a thin type pipe 10 like this example, it can be made into a rib shape by making it the structure which projects the outer peripheral surface 12 of the pipe 10 outward, and the rigidity of the pipe 10 is improved. Highly accurate assembly is possible.

  Further, in this example, a groove fuel passage 64 is formed between the concave groove 112 on the inner peripheral surface 11 of the pipe 10, the outer peripheral surface 212 of the fixed core 21, and the outer peripheral surface 222 of the movable core 22. Therefore, the groove fuel passage 64 communicates between the upstream side of the fixed core 21 and the downstream side of the movable core 22 through a route that continuously passes through the outer peripheral surface 212 of the fixed core 21 and the outer peripheral surface 222 of the movable core 22. It becomes a passage. For this reason, the vapor in the fuel is more easily removed to the upstream side of the fuel passage 6.

  A housing plate 15 as a magnetic circuit forming member that forms a magnetic circuit together with the pipe 10 and the fixed core 21 by energizing the coil 51 is disposed on the outer peripheral side of the portion of the pipe 10 that houses the fixed core 21. The groove fuel passage 64 is formed at a position not facing the housing plate 15 via the pipe 10. That is, by preventing the groove fuel passage 64 and the housing plate 15 from being arranged at positions facing each other via the pipe 10, magnetism generated in the magnetic circuit formed by the adjacent fixed core 21, pipe 10 and housing plate 15. Loss can be suppressed. As a result, the effect of providing the groove fuel passage 64 can be obtained while sufficiently securing the magnetic characteristics.

  Moreover, the pipe 10 has the protrusion part 121 which makes the outer peripheral surface 12 protrude outward in the outer peripheral surface 12 corresponding to the part in which the ditch | groove 112 is formed. Therefore, as described above, the protruding portion 121 of the pipe 10 can be formed in a rib shape. Thereby, the rigidity of the pipe 10 can be increased, and high-precision assembly is possible.

  Further, by forming the protruding portion 121 on the outer peripheral surface 12 of the pipe 10, a step is generated on the outer peripheral surface 12 of the pipe 10. Therefore, by using the axial end surface of the projecting portion 12 as a member to be assembled with the pipe 10, for example, the contact surface (seat) of the housing holder 14, the positioning of the housing holder 14 with respect to the pipe 10 is facilitated, and the assembly is improved. Can be done with precision.

  The pipe 10 is of a thin wall type having a thickness in the range of 0.1 to 0.3 mm. In the thin-walled pipe 10, it is necessary to ensure sufficient rigidity for the assembly of the fixed core 21. Therefore, the fixed core 21 can be assembled easily and with high accuracy on the inner peripheral side of the pipe 10 by forming the concave groove 112 by pressing or the like as in this example and increasing the rigidity of the pipe 10. .

  Thus, according to this example, it is possible to suppress a decrease in the fuel injection amount characteristic during use, and it is possible to provide an injector (fuel injection valve) with excellent reliability.

(Example 2)
This example is an example in which the configuration of the groove fuel passage 64 of the fuel passage 6 is changed in the injector 1 of the first embodiment.
In this example, as shown in FIGS. 4 to 6, the concave groove 112 is provided in two portions in a straight line in the axial direction in the portion of the pipe 10 that houses the fixed core 21 and the movable core 22. As shown in FIGS. 4 and 6, a belt-like gap 113 is provided over the entire circumference in the circumferential direction in the portion of the pipe 10 that houses the tip of the fixed core 21.

As shown in FIG. 4, the groove fuel passage 64 formed between the concave groove 112 on the inner peripheral surface 11 of the pipe 10 and the outer peripheral surface 212 of the fixed core 21 and the outer peripheral surface 222 of the movable core 22 The fuel passage 61 and the downstream fuel passage 63 are provided so as to communicate with each other. Further, the groove fuel passage 64 communicates with the strip gap 113, and the strip gap 113 is configured as a part of the fuel passage 6.
The other configuration is the same as that of the first embodiment, and has the same operation and effect.

(Example 3)
This example is an example in which the configuration of the fuel passage 6 is changed in the injector 1 of the first embodiment.
In this example, as shown in FIGS. 7 and 8, unlike the first embodiment, the adjusting pipe 28, the fixed core 21, and the needle 40 are not provided with a vertical hole that forms the normal fuel passage 62. Further, the fuel hole 45 of the needle 40 is not provided. That is, the injector 1 of this example is not provided with the normal fuel passage 62 of the fuel passage 6.
Other configurations are the same as those in the first embodiment.

In the case of this example, it is possible to eliminate the hole machining that has been performed to form the fuel passage 6 (normal fuel passage 62) inside the adjusting pipe 28, the movable core 22, and the needle 40, and the productivity. Improvement and cost reduction can be achieved. The fuel flow between the upstream fuel passage 61 and the downstream fuel passage 63 can be sufficiently ensured by providing the groove fuel passage 64.
The other functions and effects are the same as those of the first embodiment.

Example 4
This example is an example in which the configuration of the concave groove 112 of the pipe 10 is changed in the injector 1 of the first embodiment.
In this example, as shown in FIG. 9, the pipe 10 is of a thick wall type having a thickness of 0.7 mm. The pipe 10 includes a first magnetic part 10a, a nonmagnetic part 10b, and a second magnetic part 10c, and is integrally connected by, for example, laser welding.

  The first magnetic part 10a and the second magnetic part 10c are formed in a cylindrical shape from a magnetic material. Moreover, the nonmagnetic part 10b is formed in the cylinder shape with the nonmagnetic material. The nonmagnetic portion 10b prevents a magnetic short circuit between the first magnetic portion 10a and the second magnetic portion 10c formed of a magnetic material.

As shown in FIG. 10, an arc surface 111 and a groove 112 are formed on the inner peripheral surface 11 of the pipe 10. Unlike the first embodiment, the concave groove 112 is formed by cutting the inner peripheral surface 11 without deforming the pipe 10.
Other configurations are the same as those in the first embodiment.

In the case of this example, the pipe 10 is a thick wall type having a thickness exceeding 0.3 mm and not more than 0.7 mm. Therefore, even if the inner peripheral surface 11 of the pipe 10 is cut to form the concave groove 112, the rigidity of the pipe 10 can be sufficiently ensured. Thereby, the fixed core 21 can be assembled with high accuracy.
The other functions and effects are the same as those of the first embodiment.

(Example 5)
This example is an example in which the shape of the concave groove 112 of the pipe 10 is changed in the injector 1 of the first embodiment.
In this example, as shown in FIGS. 11 and 12, an arc surface 111 and a groove 112 are formed on the inner peripheral surface 11 of the pipe 10. The concave groove 112 is provided in a spiral shape in the axial direction.

In FIG. 11, the pipe 10 is of a thin wall type, and the concave groove 112 is formed by pressing. In FIG. 12, the pipe 10 is of a thick type, and the concave groove 112 is formed by cutting or the like.
The other configuration is the same as that of the first embodiment, and has the same operation and effect.

Explanatory drawing which shows the structure of the injector in Example 1. FIG. Explanatory drawing which shows the AA line cross section of FIG. (A) Explanatory drawing which shows the outer peripheral surface of a pipe in Example 1, (b) Explanatory drawing which shows the BB line cross section of (a), (c) Explanatory drawing which shows the CC line cross section of (b) . Explanatory drawing which shows the structure of the injector in Example 2. FIG. Explanatory drawing which shows the DD sectional view of FIG. Explanatory drawing which shows the EE sectional view of FIG. Explanatory drawing which shows the structure of the injector in Example 3. FIG. Explanatory drawing which shows the FF line cross section of FIG. Explanatory drawing which shows the structure of the injector in Example 4. FIG. Explanatory drawing which shows the GG line cross section of FIG. Explanatory drawing which shows the pipe in which the spiral groove in Example 5 was formed. Explanatory drawing which shows the pipe in which the spiral groove in Example 5 was formed.

Explanation of symbols

1 Injector (fuel injection valve)
10 Pipe (accommodating member)
11 inner peripheral surface 111 arc surface 112 concave groove 21 fixed core 212 outer peripheral surface (outer peripheral surface of fixed core)
22 movable core 222 outer peripheral surface (outer peripheral surface of movable core)
6 Fuel passage 64 Groove fuel passage

Claims (5)

A cylindrical housing member made of a magnetic material, a coil disposed on the outer circumferential side of the housing member, a fixed core made of a magnetic material disposed on the inner circumferential side of the housing member, and an inner portion of the housing member A movable core made of a magnetic material that is disposed on the circumferential side so as to face the fixed core in the axial direction and is attracted to the fixed core by a magnetic attractive force generated between the fixed core and the energization of the coil; And a valve member that moves in the axial direction together with the movable core and opens and closes a nozzle hole for injecting fuel, and communicates the upstream side of the fixed core and the downstream side of the movable core in the housing member A fuel injection valve formed with a passage,
On the inner peripheral surface of the housing member, there are an arc surface having an arc-shaped surface along the outer peripheral surface of the fixed core and the movable core, and one or a plurality of concave grooves recessed outward from the arc surface. Formed,
A groove fuel passage constituting a part of the fuel passage is formed between the concave groove on the inner peripheral surface of the housing member and the outer peripheral surface of at least one of the fixed core and the movable core. The fuel injection valve characterized by the above-mentioned.   2. The fuel according to claim 1, wherein the groove fuel passage is formed between the concave groove on the inner peripheral surface of the housing member and the outer peripheral surfaces of both the fixed core and the movable core. Injection valve. 3. The magnetic circuit forming member according to claim 1 or 2, wherein a magnetic circuit forming member that forms a magnetic circuit together with the housing member and the fixed core by energizing the coil is provided on an outer peripheral surface of a portion of the housing member that houses the stationary core. Arranged,
The fuel injection valve according to claim 1, wherein the groove fuel passage is formed at a position not facing the magnetic circuit forming member via the housing member.   In any 1 item | term of the Claims 1-3, The said accommodating member has a protrusion part which makes this outer peripheral surface protrude outward in the outer peripheral surface corresponding to the part in which the said ditch | groove is formed. A fuel injection valve.   5. The fuel injection valve according to claim 4, wherein the accommodating member has a thickness of 0.1 to 0.3 mm.

Images