JP2005282458A - Fuel injection valve and method of manufacturing fuel injection valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel injection valve enabling a magnetic member to be positioned relative to a tube member by a simple structure. <P>SOLUTION: A ring 60 is fitted to a nozzle holder 14. The ring 60 restricts the relative movement of a housing 50 to a coil 40 stored in the housing 50 in the axial direction of a storage pipe 11. When a resin forming a resin mold 33 is filled from the opposite side of a valve body 20, the coil 40 and the housing 50 are not moved relative to the storage pipe 11 in the axial direction. Accordingly, the positions of the coil 40 and the housing 50 relative to the storage pipe 11 can be determined. In addition, the welding or caulking of the housing 50 is not required. As a result, the man-hour for assembly can be reduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel injection valve for an internal combustion engine (hereinafter, the internal combustion engine is referred to as an “engine”) and a method for manufacturing the fuel injection valve.

  Conventionally, in a fuel injection valve, a valve member that opens and closes an injection hole is driven by an electromagnetic drive unit. The electromagnetic drive unit includes a coil that generates a magnetic field when energized, and a magnetic member that forms a magnetic circuit through which a magnetic flux flows together with the movable core and the fixed core by the magnetic field generated from the coil. The magnetic member is installed on the radially outer side of the coil (see Patent Document 1 and Patent Document 2).

JP-A-5-79424 Japanese Patent Laid-Open No. 2002-21678

  In the case of the fuel injection valve disclosed in Patent Document 1, the housing, which is a magnetic member, is fixed to the yoke by caulking the end portion on the injection hole side. In the case of the fuel injection valve disclosed in Patent Document 2, the end of the housing, which is a magnetic member, on the injection hole side is welded to be fixed to the yoke. When the magnetic member is fixed by caulking or welding as in the fuel injection valves disclosed in these Patent Documents 1 and 2, it is difficult to manage the precise position of the magnetic member with respect to the cylindrical member. In addition, there is a problem that a separate process is required for caulking or welding, resulting in an increase in processing man-hours.

Therefore, an object of the present invention is to provide a fuel injection valve in which the position of a magnetic member with respect to a cylindrical member is determined with a simple structure.
Another object of the present invention is to provide a method for manufacturing a fuel injection valve in which the number of steps is reduced.

  In the first aspect of the present invention, the relative position of the magnetic member in the axial direction with respect to the cylindrical member is determined by the holding member. That is, by installing the holding member on the outer peripheral side of the cylindrical member, the holding member comes into contact with the magnetic member. The relative position of the magnetic member in the axial direction with respect to the cylindrical member is determined by the holding member installed on the cylindrical member installed on the inner peripheral side. By adjusting the position of the holding member installed on the cylindrical member, the relative position of the magnetic member with respect to the cylindrical member is easily set. Therefore, the position of the magnetic member relative to the cylindrical member can be determined with a simple structure.

  In the invention according to claim 2, the cylindrical member has a guide portion for accommodating the movable core on the nozzle side. The contact portion between the magnetic member and the cylindrical member is located on the radially outer side of the movable core and the guide portion. Magnetic flux flows between the movable core and the magnetic member due to the magnetic field generated by the coil. Since the contact portion between the magnetic member and the cylindrical member is located on the radially outer side of the movable core and the guide portion, the magnetic flux easily flows from the movable core to the magnetic member. Therefore, the magnetic attractive force can be increased.

  According to a third aspect of the present invention, the magnetic member has a first end and a second end that cover the end of the coil in the axial direction, and a side that covers the outer side of the coil in the radial direction. The first end portion, the second end portion and the side portion are integrally formed without a seam. For this reason, the first end portion, the second end portion, and the side portion of the magnetic member are formed seamlessly by, for example, pressing a single plate member. Therefore, the magnetic member can have a simple structure.

  In the invention according to claim 4, the holding member is disposed on the nozzle side of the magnetic member. For example, when the resin for molding the coil and the magnetic member is injected from the side opposite to the nozzle, it is necessary to prevent the coil and the magnetic member from moving to the nozzle side due to the resin pressure at the time of injection. Therefore, by installing the holding member on the nozzle side of the magnetic member, the movement of the coil and the magnetic member to the nozzle side is restricted by the holding member. Therefore, the position of the magnetic member relative to the cylindrical member can be determined with a simple structure.

  In the invention according to claim 5, the holding member is disposed on the side opposite to the nozzle of the magnetic member. For example, when the resin for molding the coil and the magnetic member is injected from the nozzle side, the coil and the magnetic member must be prevented from moving to the nozzle side due to the resin pressure at the time of injection. Therefore, by installing the holding member on the side opposite to the nozzle of the magnetic member, the movement of the coil and the magnetic member to the side opposite to the nozzle is restricted by the holding member. Therefore, the position of the magnetic member relative to the cylindrical member can be determined with a simple structure.

  In the invention according to claim 6 or 7, the holding member is press-fitted or fitted into the cylindrical member. Therefore, the holding member is fixed to the cylindrical member, and the holding member does not move. Therefore, the position of the magnetic member relative to the cylindrical member can be managed with a simple structure. Further, the holding member can be easily installed as compared with welding or caulking. Therefore, the man-hour required for installation of a coil and a magnetic member can be reduced.

In the invention according to claim 8, the coil has a protrusion. The protruding portion regulates relative movement with the magnetic member by contacting the magnetic member. Thereby, the movement of the coil in the axial direction is restricted by both axial ends of the magnetic member, and the movement in the circumferential direction is restricted by the protrusion. Therefore, the coil can be installed at a predetermined position.
In the invention according to claim 9, the holding member is formed of any one of a non-magnetic material, a magnetic material, and a resin. Thereby, the material of the holding member is selected according to the portion to which the holding member is applied or the holding force required for holding the coil.

  In a tenth aspect of the present invention, after the coil is installed inside the magnetic member, the cylindrical member is inserted on the inner peripheral side of the coil and the magnetic member. The magnetic member and the coil are restricted from moving in the axial direction by a holding member attached to the cylindrical member. The timing for attaching the holding member to the cylindrical member may be before or after the cylindrical member is inserted into the magnetic member and the coil. By installing the holding member, the positions of the magnetic member and the coil with respect to the cylindrical member are determined. Therefore, processes such as welding or caulking are not required, and man-hours can be reduced. Further, since the movement of the magnetic member and the coil in the axial direction is restricted by the holding member, for example, the magnetic member and the coil are not moved by the resin that molds the magnetic member and the coil. Therefore, the position of the magnetic member relative to the cylindrical member can be determined with a simple structure.

  In the invention according to claim 11 or 12, the holding member is press-fitted or fitted into the cylindrical member. Therefore, the holding member is fixed to the cylindrical member, and the holding member does not move. Therefore, the position of the magnetic member relative to the cylindrical member can be managed with a simple structure.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a fuel injection valve (hereinafter referred to as “injector”) according to a first embodiment of the present invention. The injector 10 according to the first embodiment injects fuel into, for example, a gasoline engine. The injector 10 may be applied to a direct injection type gasoline engine that directly injects fuel into a combustion chamber of a gasoline engine, or may be applied to a diesel engine.

  The accommodating pipe 11 of the injector 10 is formed in a thin and substantially cylindrical shape. The accommodation pipe 11 is integrally formed without having a seam from one end in the axial direction to the other end. The accommodation pipe 11 may be formed of either a nonmagnetic material or a magnetic material. One end of the housing pipe 11 in the axial direction forms a fuel inlet 12. Fuel is supplied to the fuel inlet 12 from a fuel pump (not shown). The fuel supplied to the fuel inlet 12 flows into the inner peripheral side of the accommodation pipe 11 via the fuel filter 13. The fuel filter 13 is installed at the end of the accommodation pipe 11 and removes foreign matters contained in the fuel.

  A nozzle holder 14 is installed at the end of the accommodation pipe 11 opposite to the fuel inlet 12. The accommodation pipe 11 and the nozzle holder 14 constitute a cylindrical member described in the claims. The nozzle holder 14 constitutes a part of the cylindrical member and constitutes a guide portion. The nozzle holder 14 is formed in a substantially cylindrical shape from a magnetic material, and the valve body 20 is installed inside. The housing pipe 11 and the nozzle holder 14 are not limited to being separate and may be integrally formed.

  The valve body 20 is formed in a substantially cylindrical shape, and is fixed to the end of the nozzle holder 14 on the side opposite to the accommodation pipe 11. The valve body 20 has a valve seat 21 on a conical inner wall whose inner diameter decreases as it approaches the tip. The valve body 20 has a nozzle hole plate 22 at the end opposite to the housing pipe 11. The nozzle hole plate 22 is fixed to the valve body 20 so as to cover the end of the valve body 20 on the side opposite to the housing pipe 11. The nozzle hole plate 22 has a nozzle hole 23 that connects an end face on the valve body 20 side and an end face on the opposite side of the valve body 20. The valve body 20 and the nozzle hole plate 22 constitute a nozzle in the claims.

  The needle 24 is accommodated in the inner peripheral side of the nozzle holder 14 so as to be capable of reciprocating in the axial direction. The needle 24 is disposed substantially coaxially with the nozzle holder 14. The needle 24 is formed in a substantially cylindrical shape, and has a contact portion 25 in the vicinity of the end portion on the nozzle hole plate 22 side. The contact portion 25 can contact a valve seat 21 formed on the valve body 20. The needle 24 forms a fuel passage 26 through which fuel flows between the needle body 24 and the valve body 20. The substantially cylindrical needle 24 forms a fuel passage 27 through which fuel flows on the inner peripheral side. The needle 24 has a fuel hole 28 for connecting an inner peripheral fuel passage 27 and an outer peripheral fuel passage 26 to the side wall portion.

  The injector 10 has a drive unit 30 that drives the needle 24. The drive unit 30 is an electromagnetic drive unit, and includes a coil 40, a fixed core 31, a housing 50 as a magnetic member, and a movable core 32. As shown in FIGS. 1 and 2, the coil 40 includes a spool 41 that is formed of a resin into a cylindrical shape, and a winding 42 that is wound around the spool 41. The coil 40 has a wiring member 43 connected to the winding 42 and a terminal 44 connected to the end of the wiring member 43 opposite to the winding 42. The spool 41 has a pedestal portion 45 as a protruding portion into which a wiring member 43 connected to the winding 42 is inserted. The accommodation pipe 11 is inserted on the inner peripheral side of the cylindrical spool 41. Thereby, the coil 40 is installed on the outer peripheral side of the accommodation pipe 11.

  A fixed core 31 is installed on the inner peripheral side of the coil 40 with the accommodation pipe 11 in between. The fixed core 31 is formed in a cylindrical shape from a magnetic material such as iron. The outer periphery side of the coil 40 and the housing 50 and the accommodation pipe 11 is covered with a resin mold 33. The winding 42 of the coil 40 is electrically connected to a terminal 44 installed on the connector 34 via a wiring member 43. The connector 34 is integrally formed with a resin mold 33.

  The housing 50 is made of a magnetic material and covers both ends of the coil 40 in the axial direction and the outside in the radial direction as shown in FIG. The housing 50 has a first end 51, a second end 52, and a side 53 as shown in FIGS. The side portion 53 extends along the axial direction on the radially outer side of the coil 40. Thereby, the side part 53 has covered a part of circumferential direction in the radial direction outer side of the coil 40. As shown in FIG. The first end portion 51 and the second end portion 52 are respectively connected to both end portions of the side portion 53 in the axial direction. The first end portion 51 covers the coil 40 on the valve body 20 side of the side portion 53. The second end 52 covers the coil 40 on the side 53 opposite to the valve body 20. As a result, the housing 50 has a substantially U-shaped cross section along the axis. As shown in FIG. 3, the first end 51 of the housing 50 has a hole 54 into which the accommodation pipe 11 is inserted at the center. The inner wall of the first end 51 forming the hole 54 is in contact with the outer wall of the nozzle holder 14.

  The second end 52 of the housing 50 has a recess 55 in which the accommodation pipe 11 is accommodated at the center. The inner wall of the second end 52 that forms the recess 55 is in contact with the outer wall of the housing pipe 11. Therefore, the housing 50 is in contact with the nozzle holder 14 on one side in the axial direction and is in contact with the receiving pipe 11 on the other side. Since the second end portion 52 has the concave portion 55 at the center portion, the second end portion 52 has a convex portion 56 and a convex portion 57 on the radially outer side of the concave portion 55.

  As shown in FIG. 1, the housing 50 accommodates the coil 40 inside. A pedestal 45 is formed on the spool 41 of the coil 40. When the coil 40 is housed in the housing 50, the side portion 56a on the convex portion 57 side of the convex portion 56 and the side portion 57a on the convex portion 56 side of the convex portion 57 shown in FIG. Contact with the pedestal 45 is possible. When the coil 40 is accommodated in the housing 50, the convex portion 56 or the convex portion 57 and the pedestal portion 45 of the spool 41 come into contact with each other, whereby relative rotation in the circumferential direction between the coil 40 and the housing 50 is restricted. The

  As shown in FIG. 3, the first end 51, the second end 52, and the side 53 of the housing 50 are integrally formed by one member without a joint. The housing 50 is formed by pressing a plate member, for example, so that a hole 54 is formed in the first end 51, and a recess 55, a protrusion 56, and a protrusion 57 are formed in the second end 52. And the board | plate member in which the hole part 54, the recessed part 55, the convex part 56, and the convex part 57 were formed is shape | molded as the integral housing 50 seamlessly.

  As shown in FIG. 1, the movable core 32 is installed on the inner peripheral side of the nozzle holder 14 so as to be capable of reciprocating in the axial direction. The movable core 32 faces the fixed core 31 at the end opposite to the nozzle hole 23. The outer wall of the movable core 32 is slidable with the inner wall of the nozzle holder 14. The movable core 32 is formed in a substantially cylindrical shape from a magnetic material such as iron. An end of the movable core 32 opposite to the contact portion 25 of the needle 24 is fixed on the inner peripheral side. The needle 24 and the movable core 32 are fixed by, for example, press fitting or welding. Thereby, the needle 24 and the movable core 32 reciprocate in the axial direction integrally. The first end 51 is opposed to the movable core 32 with the nozzle holder 14 in between.

  The end of the needle 24 fixed to the inner peripheral side of the movable core 32 is in contact with the spring 15 as an elastic member. The spring 15 has one end in contact with the needle 24 and the other end in contact with the adjusting pipe 16. The spring 15 has a force that extends in the axial direction. Therefore, the needle 24 integral with the movable core 32 is pressed by the spring 15 in the direction of seating on the valve seat 21. The adjusting pipe 16 is press-fitted into the fixed core 31. Therefore, the pressing force of the spring 15 is adjusted by adjusting the press-fitting amount of the adjusting pipe 16. When the coil 40 is not energized, the movable core 32 and the needle 24 are pressed toward the valve seat 21, and the contact portion 25 is seated on the valve seat 21.

  The first end 51 of the housing 50 is in contact with a ring 60 as a holding member. The ring 60 is fitted on the radially outer side of the nozzle holder 14 on the valve body 20 side of the housing 50. As shown in FIG. 4, the ring 60 has a substantially C-shaped cross section perpendicular to the axis. That is, the ring 60 includes a circular arc portion 61 and an opening portion 62 that are substantially arc-shaped. As shown in FIGS. 1 and 5, the nozzle holder 14 is formed with a recess 17 that is recessed inward in the radial direction. As shown in FIG. 5, the ring 60 is fitted into the recess 17 from the outside in the radial direction of the nozzle holder 14 and fixed to the nozzle holder 14. The ring 60 regulates the movement of the housing 50 and the coil 40 accommodated in the housing 50 by the surface on the housing 50 side being in contact with the first end portion 51 of the housing 50. Thereby, the relative movement in the axial direction of the housing 50 and the coil 40 and the accommodating pipe 11 and the nozzle holder 14 is restricted. The ring 60 is made of a nonmagnetic material, a magnetic material, a resin, or the like. The material of the ring 60 is selected according to the portion to be applied and the holding force of the coil 40.

Next, assembly of the injector 10 having the above configuration will be described.
A coil 40 is accommodated inside the housing 50. The coil 40 is accommodated inside the housing 50 from the side of the housing 50. At this time, when the second end portion 52 of the housing 50 comes into contact with the pedestal portion 45 of the coil 40, the relative rotational movement of the housing 50 and the coil 40 in the circumferential direction is restricted.

  When the coil 40 and the housing 50 are assembled, the housing pipe 11 is installed in the housing 50 in which the coil 40 is housed as shown in FIG. At this time, the nozzle holder 14 is connected to the accommodation pipe 11. The nozzle holder 14 is provided with a valve body 20 and an injection hole plate 22. The accommodation pipe 11 is inserted into the inner peripheral side of the cylindrical coil 40 and is inserted into the hole 54 and the recess 55 of the housing 50. The valve body 20 and the nozzle hole plate 22 may be installed in a later process. A ring 60 is attached to the nozzle holder 14. The ring 60 may be attached to the nozzle holder 14 before the accommodation pipe 11 is inserted into the coil 40 and the housing 50, or may be attached to the nozzle holder 14 after the accommodation pipe 11 is inserted into the coil 40 and the housing 50.

  The ring 60 is fitted into the recess 17 from the outside in the radial direction of the nozzle holder 14. As a result, the coil 40 and the housing 50 are inserted into the housing pipe 11 and are in contact with the ring 60 attached to the nozzle holder 14 integral with the housing pipe 11, thereby restricting relative movement in the axial direction. In the case of this embodiment, the ring 60 is installed on the first end portion 51 side of the housing 50. Therefore, the coil 40 and the housing 50 are allowed to move upward in FIG. 1, but are restricted from moving downward in FIG. The coil 40 is accommodated inside the housing 50. Therefore, the coil 40 is restricted from moving in the axial direction by contacting the first end 51 or the second end 52.

  When the relative positions of the coil 40 and the housing 50 and the receiving pipe 11 are determined by the ring 60, the resin mold 33 is formed outside the receiving pipe 11, the coil 40 and the housing 50 installed in a molding die (not shown). Is done. The resin mold 33 is molded by inserting the housing pipe 11, the coil 40, and the housing 50 by injecting molten resin into a molding die (not shown). The resin forming the resin mold 33 is injected from the upper side in FIG. 1, that is, from the end opposite to the nozzle holder 14. Therefore, when the resin forming the resin mold 33 is injected, a force pressing the coil 40 and the housing 50 toward the nozzle holder 14 is applied. On the other hand, in the case of this embodiment, the housing 50 is in contact with the ring 60 attached to the nozzle holder 14 at the first end 51. Thereby, even if the coil 40 and the housing 50 are pressed against the nozzle holder 14 side as the resin is injected, the movement of the coil 40 and the housing 50 toward the nozzle holder 14 side is limited.

When the injection of the resin forming the resin mold 33 is completed, the needle 24 integrated with the movable core 32 and the fixed core 31 are installed inside the accommodation pipe 11. The fixed core 31 is press-fitted inside the accommodation pipe 11. Further, the spring 15 and the adjusting pipe 16 are installed on the inner peripheral side of the fixed core 31. Before injecting the resin forming the resin mold 33, the needle 24 integrated with the movable core 32, the fixed core 31, and the like may be installed inside the accommodation pipe 11.
In the above assembling procedure, assembling of main members such as insertion of the housing pipe 11 into the housing 50 housing the coil 40, formation of the resin mold 33, insertion of the needle 24 and the movable core 32, and press-fitting of the fixed core 31 are performed. Can be carried out in one direction, ie from the fuel inlet 12 side. Therefore, simplification of the assembly facility of the injector 10 is achieved.

Next, the operation of the injector 10 having the above configuration will be described.
When energization of the coil 40 is stopped, no magnetic attractive force is generated between the fixed core 31 and the movable core 32. Therefore, the movable core 32 is moved to the opposite side of the fixed core 31 by the pressing force of the spring 15. Thereby, the needle 24 integrated with the movable core 32 moves to the opposite side to the fixed core 31. As a result, when the energization to the coil 40 is stopped, the contact portion 25 of the needle 24 is seated on the valve seat 21. Therefore, fuel is not injected from the injection hole 23.

  When the coil 40 is energized, a magnetic circuit is formed in the housing 50, the nozzle holder 14, the movable core 32 and the fixed core 31 by the magnetic field generated in the coil 40, and a magnetic flux flows. Both the first end 51 of the housing 50 and the nozzle holder 14 in contact with the first end 51 are made of a magnetic material. Therefore, the magnetic resistance between the nozzle holder 14 and the housing 50 is small.

  The housing pipe 11 is sandwiched between the second end 52 of the housing 50 and the fixed core 31. When the accommodation pipe 11 is formed of a nonmagnetic material, the accommodation pipe 11 is thin, so that the magnetic flux is sufficiently transmitted between the second end 52 and the fixed core 31. Therefore, even if the accommodation pipe 11 is formed from a nonmagnetic material, the magnetic resistance between the second end 52 of the housing 50 and the fixed core 31 is reduced. On the other hand, when the accommodation pipe 11 is formed of a magnetic material, it is conceivable that the magnetic flux is short-circuited from the nozzle holder 14 to the fixed core 31 via the accommodation pipe 11. However, since the accommodation pipe 11 is thin, the magnetic flux that short-circuits the accommodation pipe 11 is easily saturated. Therefore, even if the accommodation pipe 11 is made of a magnetic material, a short circuit of magnetic flux via the accommodation pipe 11 is reduced.

  As described above, even if the housing pipe 11 is formed of a nonmagnetic material or a magnetic material, an increase in magnetic resistance or a short circuit of magnetic flux is reduced. Thereby, a magnetic circuit in which magnetic flux flows through the housing 50, the nozzle holder 14, the movable core 32, and the fixed core 31 is formed by the magnetic field generated in the coil 40. As a result, when the coil 40 is energized, a magnetic attractive force is generated between the fixed core 31 and the movable core 32 that are separated from each other by the biasing force of the spring 15. When the magnetic attractive force generated between the fixed core 31 and the movable core 32 becomes larger than the pressing force of the spring 15, the movable core 32 moves in the direction of the fixed core 31 together with the integral needle 24. Thereby, the contact portion 25 of the needle 24 is separated from the valve seat 21.

  The fuel that flows into the injector 10 from the fuel inlet 12 flows into the fuel filter 13, the inner peripheral side of the accommodating pipe 11, the inner peripheral side of the adjusting pipe 16, the inner peripheral side of the fixed core 31, and the inner peripheral side of the movable core 32. Then, the fuel flows into the fuel passage 26 via the fuel passage 27 and the fuel hole 28 on the inner peripheral side of the needle 24. The fuel that has flowed into the fuel passage 26 flows into the nozzle hole 23 formed by the nozzle hole plate 22 via the space between the needle 24 separated from the valve seat 21 and the valve body 20. Thereby, fuel is injected from the injection hole 23.

  When energization of the coil 40 is stopped, the magnetic attractive force between the fixed core 31 and the movable core 32 disappears. As a result, the movable core 32 integral with the needle 24 moves to the opposite side of the fixed core 31 by the pressing force of the spring 18. Therefore, the contact portion 25 is seated on the valve seat 21 again, and the fuel flow between the fuel passage 26 and the injection hole 23 is blocked. Therefore, the fuel injection ends.

  As described above, in the first embodiment described above, the relative movement of the coil 40 and the housing 50 with respect to the housing pipe 11 is restricted by the ring 60 installed in the nozzle holder 14. Therefore, when injecting the resin forming the resin mold 33, the coil 40, the housing 50, and the receiving pipe 11 do not move relative to each other in the axial direction. Further, when the second end portion 52 of the housing 50 is in contact with the pedestal portion 45 of the coil 40, relative movement in the circumferential direction between the coil 40 and the housing 50 is restricted. Therefore, the positional relationship in the circumferential direction between the coil 40 and the housing 50 does not change. Therefore, the position of the coil 40 and the housing 50 with respect to the accommodation pipe 11 can be determined with a simple structure.

Moreover, in 1st Embodiment, the housing 50 is shape | molded as a one-piece | unit with the 1st end part 51, the 2nd end part 52, and the side part 53 seamlessly. Therefore, the housing 50 forms a magnetic circuit in which magnetic flux flows by a magnetic field generated in the coil 40 as a single member. Therefore, the structure of the housing 50 can be simplified, and the number of parts can be reduced.
Furthermore, it is not necessary to weld or caulk the end of the housing 50 in order to determine the position with respect to the receiving pipe 11 and the nozzle holder 14. Therefore, the man-hours required for installing the coil 40 and the housing 50 can be reduced.

(Second Embodiment)
An injector according to a second embodiment of the present invention is shown in FIG. Components that are substantially the same as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
In the second embodiment, a ring 70 is fixed by press-fitting on the radially outer side of the nozzle holder 14. In the second embodiment, the ring 70 may be either an annular shape or an arc shape as in the first embodiment. When the ring 70 is press-fitted into the nozzle holder 14, the nozzle holder 14 does not have a portion corresponding to the concave portion in the first embodiment. In the second embodiment, when the ring 70 is attached to the nozzle holder 14, the ring 70 is press-fitted into the nozzle holder 14 from the axial end portion of the nozzle holder 14, that is, the end portion on the injection hole 23 side.
In the second embodiment, the movement of the coil 40 and the housing 50 in the axial direction is restricted by the ring 70 as in the first embodiment. Therefore, the coil 40 and the housing 50 can be installed at predetermined positions with respect to the housing pipe 11 with a simple structure.

(Third, fourth, fifth and sixth embodiments)
The injector housings according to the third, fourth, fifth and sixth embodiments of the present invention are shown in FIGS. 7, 8, 9 or 10, respectively. In addition, the same code | symbol is attached | subjected to the component substantially the same as 1st Embodiment, and description is abbreviate | omitted.
In the third embodiment, as shown in FIG. 7, the second end portion 52 of the housing 50 has a smaller amount of protrusion from the side portion 53 side than the first end portion 51. The housing 50 may be held without being inclined with respect to the accommodation pipe 11. Therefore, the protrusion amount from the side part 53 may be reduced if the second end part 52 can come into contact with both end parts in the radial direction of the housing 50. In the third embodiment, the convex portion 56 and the convex portion 57 of the second end portion 52 are in contact with the pedestal portion 45 of the coil 40. Thereby, the relative rotation of the coil 40 and the housing 50 in the circumferential direction is restricted.

In the fourth embodiment, as shown in FIG. 8, the first end 51 and the second end 52 of the housing 50 are formed substantially concentrically with the accommodation pipe 11. The second end 52 has a hole 58 into which the receiving pipe 11 is inserted and a notch 59 on the side opposite to the side 53 of the hole 58. The second end 52 can be expanded and contracted in the circumferential direction at intervals of the notches 59. When the notch 59 of the second end portion 52 expands and contracts in the circumferential direction, when the accommodation pipe 11 is inclined with respect to the axis, the inclination is absorbed by the expansion and contraction of the second end portion 52. Therefore, the force applied to the accommodation pipe 11 is reduced, and deformation of the accommodation pipe 11 can be reduced.
In the fourth embodiment, the notch 59 is fitted with a pedestal portion 45 of the coil 40 or a projection (not shown) formed on the pedestal portion 45. Thereby, the relative rotation of the coil 40 and the housing 50 in the circumferential direction is restricted.

  In the fifth embodiment, as shown in FIG. 9, the housing 80 has a first side portion 81 and a second side portion 82 that are substantially parallel to the axis of the receiving pipe 11. The first side portion 81 and the second side portion 82 face each other at both ends in the radial direction of the housing pipe 11. A first end portion 83 is connected to the first side portion 81 and the second side portion 82 on the nozzle hole 23 side. The first end 83 has a hole 84 through which the accommodation pipe 11 penetrates at the center. Second end portions 85 and 86 that protrude toward the center in the radial direction are connected to the opposite sides of the first side portion 81 and the first end portion 83 of the second side portion 82 in the axial direction. The second end portion 85 projecting from the first side portion 81 and the second end portion 86 projecting from the second side portion 82 form a housing portion 87 into which the housing pipe 11 is inserted at the central portion. The pedestal 45 of the coil 40 is sandwiched between the second end 85 and the second end 86. Thereby, the relative rotation of the coil 40 and the housing 80 in the circumferential direction is restricted.

  In the fifth embodiment, the coil 40 is covered by the housing 50 at both ends in the radial direction by installing the first side portion 81 and the second side portion 82 that are parallel to the accommodation pipe 11. Therefore, the flow of magnetic flux is made uniform at both ends of the coil 40 in the radial direction, and the magnetic attractive force can be stabilized and increased. In the fifth embodiment, the housing 80 includes the first side portion 81 and the second side portion 82, so that the strength against axial and radial loads increases. Therefore, deformation of the accommodation pipe 11 can be reduced.

  In the sixth embodiment, as shown in FIG. 10, the housing 90 has a first side portion 91 and a second side portion 92 that are substantially parallel to the axis of the receiving pipe 11. The first side portion 91 and the second side portion 92 are opposed to each other at both ends in the radial direction of the accommodation pipe 11. First end portions 93 and 94 projecting toward the radial center are connected to the first side portion 91 and the second side portion 92 on the nozzle hole 23 side. The first end portion 93 protruding from the first side portion 91 and the first end portion 94 protruding from the second side portion 92 form a storage portion 95 into which the storage pipe 11 is inserted at the center portion. A second end portion 96 is connected to the first side portion 91 and the second side portion 92 opposite to the first end portions 93 and 94 in the axial direction. The second end 96 has a hole 97 through which the accommodation pipe 11 penetrates at the center. That is, the housing 90 according to the sixth embodiment has a shape obtained by inverting the housing 80 according to the fifth embodiment shown in FIG. 9 in the axial direction.

In the sixth embodiment, similarly to the fifth embodiment, the flow of magnetic flux is made uniform at both ends in the radial direction of the coil 40, and the magnetic attractive force can be stabilized and increased. Moreover, in 6th Embodiment, the intensity | strength with respect to the load of an axial direction and radial direction increases, and the deformation | transformation of the accommodation pipe 11 can be reduced.
In the case of the sixth embodiment, the coil 40 has a projection (not shown) that projects from the spool 41 to the opposite side of the pedestal 45. A protrusion (not shown) protruding from the coil 40 is sandwiched between the first end portion 93 and the first end portion 94. Thereby, the relative rotation of the coil 40 and the housing 90 in the circumferential direction is restricted.

In the plurality of embodiments described above, the example in which the injection hole plate 22 that forms the injection hole 23 at the distal end portion of the valve body 20 has been described. However, instead of forming the injection hole 23 in the injection hole plate 22, the injection hole 23 may be formed in the valve body 20.
In the above embodiments, the example in which the ring that is the holding member is installed on the injection hole side of the housing and the resin that forms the mold is injected from the side opposite to the injection hole has been described. However, the ring may be installed on the opposite side of the housing from the injection hole, and the resin forming the mold may be injected from the injection hole side. Moreover, it is good also as a structure which installs a ring in the both ends of the axial direction of a housing, and controls the axial movement of a coil and a housing with respect to a cylindrical member.

  Further, in the above embodiments, the example in which the cylindrical member is formed from the nonmagnetic material and the nozzle holder is formed from the magnetic material has been described. However, the cylindrical member and the nozzle holder can be formed of either a nonmagnetic material or a magnetic material depending on the required performance.

It is sectional drawing which shows the injector by 1st Embodiment of this invention. It is a figure which shows the coil of the injector by 1st Embodiment of this invention. It is a schematic perspective view which shows the housing of the injector by 1st Embodiment of this invention. It is the schematic which shows the ring of the injector by 1st Embodiment of this invention. It is the schematic explaining the assembly | attachment of the injector by 1st Embodiment of this invention. It is sectional drawing which shows the injector by 2nd Embodiment of this invention. It is a schematic perspective view which shows the housing of the injector by 3rd Embodiment of this invention. It is a schematic perspective view which shows the housing of the injector by 4th Embodiment of this invention. It is a schematic perspective view which shows the housing of the injector by 5th Embodiment of this invention. It is a schematic perspective view which shows the housing of the injector by 6th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Injector, 11 Housing pipe (cylinder member), 14 Nozzle holder (cylinder member, guide part), 20 Valve body (nozzle), 22 Injection hole plate (nozzle), 23 Injection hole, 40 Coil, 45 Base part (protrusion part) ), 50, 80, 90 Housing (magnetic member), 51, 83, 93, 94 First end, 52, 85, 86, 96 Second end, 53 Side, 60 Ring (holding member), 70 Ring 81, 91 First side (side), 82, 92 Second side (side)

Claims (12)

A coil that generates a magnetic field when energized;
A magnetic member that covers at least a part of the coil in the circumferential direction on both ends in the axial direction of the coil and on the radially outer side of the coil;
A cylindrical member installed on the inner peripheral side of the coil and the magnetic member;
A holding member that is installed on an outer peripheral side of the cylindrical member and determines a relative position in the axial direction of the magnetic member with respect to the cylindrical member;
A fuel injection valve comprising a nozzle having an injection hole for injecting fuel, which is installed on one end side in the axial direction of the cylindrical member. The cylindrical member has a guide portion that accommodates the movable core in a reciprocating manner on the nozzle side,
2. The fuel injection valve according to claim 1, wherein a contact portion between the magnetic member and the cylindrical member is located on a radially outer side of the movable core and the guide portion.   The magnetic member includes a first end portion covering an end portion of the coil on the nozzle side, a second end portion covering an end portion of the coil opposite to the nozzle, and a side covering a radially outer side of the coil. 3. The fuel injection valve according to claim 1, wherein the first end portion, the second end portion, and the side portion are integrally formed without a seam.   4. The fuel injection valve according to claim 1, wherein the holding member is installed on the nozzle side of the magnetic member.   4. The fuel injection valve according to claim 1, wherein the holding member is installed on a side of the magnetic member opposite to the nozzle.   The fuel injection valve according to claim 1, wherein the holding member is press-fitted into the cylindrical member.   The fuel injection valve according to any one of claims 1 to 5, wherein the holding member is fitted to the cylindrical member.   The fuel injection according to any one of claims 1 to 7, wherein the coil has a protrusion that restricts relative movement of the magnetic member in the circumferential direction by contacting the magnetic member. valve.   The fuel injection valve according to any one of claims 1 to 7, wherein the holding member is formed of any one of a nonmagnetic material, a magnetic material, and a resin. A coil that generates a magnetic field when energized;
A magnetic member that covers at least a part of the coil in the circumferential direction on both ends in the axial direction of the coil and on the radially outer side of the coil;
A cylindrical member installed on the inner peripheral side of the coil and the magnetic member;
A fuel injection valve manufacturing method comprising: a holding member that determines an axial relative position of the magnetic member with respect to the cylindrical member;
Installing the coil on the magnetic member;
Inserting the cylindrical member on the inner peripheral side of the magnetic member provided with the coil;
Attaching the holding member to the cylindrical member;
A fuel injection valve manufacturing method comprising:   The method for manufacturing a fuel injection valve according to claim 10, wherein the holding member is press-fitted in an axial direction from an axial end portion of the cylindrical member.   The method for manufacturing a fuel injection valve according to claim 10, wherein the holding member is fitted to the cylindrical member from the outside in the radial direction of the cylindrical member.

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