JP2007239561A - Fuel injection valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel injection valve capable of preventing a drive coil from being deformed and the accuracy of the position relation of a spool to a magnetic cylindrical body from being lowered in a molding step for a resin material. <P>SOLUTION: A ring part 62b projecting toward a holder 11 is formed on the spool 62 on the contact part side end 15a of a housing 15, and brought into contact with the holder 11. In the molding step for the resin material, the filled resin material is prevented from flowing into a gap between the inner peripheral part of the spool 62 and the outer peripheral part of the holder 11. Consequently, an injector 10 capable of preventing the drive coil 64 from being deformed and the accuracy of the position relation (concentricity) of the drive coil 64 to the holder 11 from being lowered in the molding step for the resin material can be provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel injection valve.

  As a conventional fuel injection valve, which is used for an internal combustion engine for automobiles, for example, in order to accurately adjust the fuel injection amount, the valve portion is opened and closed by an electromagnetic drive portion. There is known one whose time is variably adjusted. (For example, refer to Patent Document 1).

  This fuel injection valve is roughly divided into a magnetic cylinder that forms part of a magnetic circuit, a valve seat attached to one end of the magnetic cylinder, and an axially displaceable valve body that is attached to and detached from the valve seat. A valve portion comprising a valve body and a drive coil that is arranged coaxially on the outer periphery of the magnetic cylinder and generates an electromagnetic force that moves the valve body; and a magnetic circuit that is disposed on the outer periphery of the magnetic cylinder with the drive coil interposed therebetween And a metal outer frame member whose tip is fitted and brought into contact with the magnetic cylinder so as to form a part of the metal outer frame member.

In this type of fuel injection valve, a magnetic material and a metal outer frame member are attached and fixed while covering a drive coil by molding a resin material.
JP 2004-270490 A

  In the conventional fuel injection valve described above, a gap is provided between the inner periphery of the spool and the outer periphery of the magnetic cylinder in order to improve the fitting workability between the spool and the magnetic cylinder. For this reason, when the resin material is molded, the injected resin material may flow into the gap.

  At this time, the resin inflow state into the gap between the spool inner periphery and the magnetic cylinder outer periphery is influenced by the gate position and the like during resin molding, and therefore does not flow uniformly from the entire circumference of the magnetic cylinder. Therefore, the pressure of the resin flowing into the clearance between the spool inner periphery and the magnetic cylinder outer periphery may partially act on the entire spool inner peripheral surface without acting uniformly, and the drive coil may be deformed.

  Also, the pressure of the resin flowing into the gap between the inner circumference of the spool and the outer circumference of the magnetic cylinder causes the spool to move with respect to the magnetic cylinder, and the positional relation accuracy between the spool and the magnetic cylinder, that is, the coaxiality of both Etc. may be reduced. When the coaxiality between the spool and the magnetic cylinder is lowered, the electromagnetic force generated by the drive coil acts asymmetrically on the valve body, which may reduce the accuracy of operation of the valve body.

  Accordingly, the present invention has been made in view of the above problems, and provides a fuel injection valve capable of preventing deformation of a drive coil and a decrease in accuracy of positional relationship between a spool and a magnetic cylinder in a molding process of a resin material. The purpose is to do.

  In order to achieve the above object, the present invention employs the following technical means.

  The fuel injection valve according to claim 1 of the present invention is a magnetic circuit for driving the movable body by accommodating the movable body and the valve member engaged with the movable body so as to be capable of reciprocating in the axial direction. A drive coil for operating a magnetic circuit having a part of a metal inner cylinder member, a coil that generates an electromagnetic force when energized, and a resin spool around which the coil is wound, and a metal inner cylinder member At least one of a metal outer frame member that is disposed on the outer periphery with the drive coil interposed therebetween and has a distal end abutting the metal inner cylinder member so as to be another part of the magnetic circuit, and an outer peripheral surface of the metal outer frame member And a resin outer cover member that covers the metal inner cylinder member and is arranged coaxially on the outer periphery of the metal inner cylinder member, and the outer peripheral surface of the metal inner cylinder member and the inner peripheral surface of the spool A fuel injection valve in which a gap is formed between the spool and the gold It is characterized in that it comprises a ring portion projecting metal inner tubular member side at the contact portion side end portion of the outer frame member and the metal inner tubular member.

  In the above-described configuration, the radial gap between the ring portion and the metal inner cylinder member that is a magnetic cylinder is smaller than the radial gap between the general portion excluding the ring portion of the spool and the metal inner cylinder member. . That is, the area of the passage of the resin material injected in the resin material molding step to the gap between the spool inner periphery and the metal inner cylinder member outer periphery is reduced. Therefore, by providing the ring portion, the injected resin material can be prevented from flowing into the gap between the spool inner periphery and the metal inner cylinder member outer periphery.

  As a result, it is possible to provide a fuel injection valve that can prevent deformation of the drive coil and deterioration in positional relationship accuracy between the spool and the metal inner cylinder member.

  The fuel injection valve according to claim 2 of the present invention is characterized in that the ring portion and the metal inner cylinder member are in close contact with each other.

  According to the above-described configuration, the radial gap between the ring portion and the metal inner cylinder member is substantially zero, that is, there is no gap. Therefore, it is possible to reliably prevent the resin material injected in the resin material molding step from flowing into the gap between the spool inner periphery and the metal inner cylinder member outer periphery.

  In this case, the ring portion of the spool and the metal inner cylinder member are in an interference fit state, that is, the inner diameter dimension of the ring section is slightly larger than the outer diameter dimension of the metal inner cylinder member. However, since the axial length of the ring portion is much shorter than the axial length of the spool, the operation of fitting the spool and the metal inner cylinder member can be performed relatively easily.

  The fuel injection valve according to claim 3 of the present invention is characterized in that the ring portion does not reach the back side of the coil in the axial direction.

  When the spool and the metal inner cylinder member are fitted, the inner diameter dimension of the ring portion is enlarged and the ring portion is deformed. Accordingly, there is a possibility that the spool is also partially deformed as the ring portion is deformed.

  In the above configuration, since the ring portion does not extend to the back side of the coil in the axial direction, the coil winding portion of the spool is hardly deformed even when the spool and the metal inner cylinder member are fitted. Does not deform.

  As a result, it is possible to effectively prevent the resin material from flowing into the clearance between the inner periphery of the spool and the outer periphery of the metal inner cylinder by fitting the ring portion and the inner metal cylinder member into an interference fit. Can be prevented from being deformed.

  As a result, it is possible to provide a fuel injection valve that can prevent deformation of the drive coil and deterioration in positional relationship accuracy between the spool and the metal inner cylinder member.

  A fuel injection valve according to claim 4 of the present invention is a magnetic circuit for driving the movable body by accommodating the movable body and the valve member engaged with the movable body so as to reciprocate in the axial direction. A drive coil for operating a magnetic circuit having a part of a metal inner cylinder member, a coil that generates an electromagnetic force when energized, and a resin spool around which the coil is wound, and a metal inner cylinder member At least one of a metal outer frame member that is disposed on the outer periphery with the drive coil interposed therebetween and has a distal end abutting the metal inner cylinder member so as to be another part of the magnetic circuit, and an outer peripheral surface of the metal outer frame member And a resin outer cover member that covers the metal inner cylinder member and is arranged coaxially on the outer periphery of the metal inner cylinder member, and the outer peripheral surface of the metal inner cylinder member and the inner peripheral surface of the spool A fuel injection valve in which a gap is formed between the spool and the gold It is characterized in that it comprises an outer frame member and the tubular portion of the extended issued and metal inner tubular member coaxially to the contact portion in the contact portion side end portion of the metal inner tubular member.

  In the above-described configuration, the cylinder portion of the spool is disposed so as to cover the surface of the metal inner cylinder member. Therefore, the area of the passage through which the resin material injected in the resin material molding step reaches the gap between the spool inner periphery and the magnetic cylinder outer periphery is reduced. Therefore, by providing the ring portion, it is possible to suppress the injected resin material from flowing into the gap between the spool inner periphery and the magnetic cylinder outer periphery.

  As a result, it is possible to provide a fuel injection valve that can prevent deformation of the drive coil and deterioration in positional relationship accuracy between the spool and the metal inner cylinder member.

  The fuel injection valve according to claim 5 of the present invention is characterized in that the tip of the cylindrical portion abuts on the metal outer frame member.

  According to the above-described configuration, the radial gap between the distal end portion of the cylindrical portion and the metal inner cylindrical member is substantially zero, that is, there is no gap. Therefore, the resin material injected in the molding process of the resin material can be reliably prevented from flowing into the gap between the spool inner periphery and the magnetic cylinder outer periphery.

  The fuel injection valve according to claim 6 of the present invention is a magnetic circuit for driving the movable body by accommodating the movable body and the valve member engaged with the movable body so as to be capable of reciprocating in the axial direction. A drive coil for operating a magnetic circuit having a part of a metal inner cylinder member, a coil that generates an electromagnetic force when energized, and a resin spool around which the coil is wound, and a metal inner cylinder member At least one of a metal outer frame member that is disposed on the outer periphery with the drive coil interposed therebetween and has a distal end abutting the metal inner cylinder member so as to be another part of the magnetic circuit, and an outer peripheral surface of the metal outer frame member And a resin outer cover member that covers the metal inner cylinder member and is arranged coaxially on the outer periphery of the metal inner cylinder member, and the outer peripheral surface of the metal inner cylinder member and the inner peripheral surface of the spool A fuel injection valve with a gap between the spool and the metal It is characterized by providing a plurality of protrusions on at least one of the outer peripheral surface of the inner circumferential surface and the metal inner cylinder member of the spool at the insertion portion of the cylindrical member.

  According to the above-described configuration, the gap between the convex portion and the counterpart component is smaller than the gap between the inner peripheral surface of the spool and the outer peripheral surface of the metal inner cylinder member. Therefore, even if the resin material injected in the molding process of the resin material flows into the gap between the inner circumference of the spool and the outer circumference of the magnetic cylinder, and the spool receives a radial force due to the resin, the spool and the metal inner cylinder member The coaxiality is maintained well, and there is almost no deformation of the coil winding portion of the spool.

  As a result, it is possible to provide a fuel injection valve that can prevent deformation of the drive coil and deterioration in positional relationship accuracy between the spool and the metal inner cylinder member.

  The fuel injection valve according to claim 7 of the present invention is a magnetic circuit for driving the movable body by accommodating the movable body and the valve member engaged with the movable body so as to reciprocate in the axial direction. A drive coil for operating a magnetic circuit having a part of a metal inner cylinder member, a coil that generates an electromagnetic force when energized, and a resin spool around which the coil is wound, and a metal inner cylinder member At least one of a metal outer frame member that is disposed on the outer periphery with the drive coil interposed therebetween and has a distal end abutting the metal inner cylinder member so as to be another part of the magnetic circuit, and an outer peripheral surface of the metal outer frame member And a resin outer cover member that covers the metal inner cylinder member and is arranged coaxially on the outer periphery of the metal inner cylinder member, and the outer peripheral surface of the metal inner cylinder member and the inner peripheral surface of the spool The fuel injection valve has a gap formed between the spool and the spool. It is characterized by being pressed in close contact with the metal inner tubular member in the portion not applied to the rear side of the coil in the axial direction.

  In the above-described configuration, the spool is press-fitted into the metal inner cylinder member at both sides of the coil in the axial direction, that is, at both ends of the spool.

  As a result, the resin material injected in the molding process of the resin material can be surely prevented from flowing into the gap between the back side portion of the coil on the inner periphery of the spool and the outer periphery of the metal inner cylinder member. Deformation can be prevented and the positional accuracy between the coil and the metal inner cylinder member can be maintained satisfactorily.

  Moreover, since the press-fitting portion of the spool with the metal inner cylinder member does not reach the back side of the coil, it is possible to prevent the coil winding portion from being deformed during the press-fitting operation of the spool.

  The fuel injection valve according to claim 8 of the present invention is a magnetic circuit for driving the movable body by accommodating the movable body and the valve member engaged with the movable body so as to reciprocate in the axial direction. A drive coil for operating a magnetic circuit having a part of a metal inner cylinder member, a coil that generates an electromagnetic force when energized, and a resin spool around which the coil is wound, and a metal inner cylinder member At least one of a metal outer frame member that is disposed on the outer periphery with the drive coil interposed therebetween and has a distal end abutting the metal inner cylinder member so as to be another part of the magnetic circuit, and an outer peripheral surface of the metal outer frame member And a resin outer cover member that covers the metal inner cylinder member and is arranged coaxially on the outer periphery of the metal inner cylinder member, and the outer peripheral surface of the metal inner cylinder member and the inner peripheral surface of the spool The fuel injection valve has a gap formed between the spool and the spool. Comprising a projecting portion projecting outward, spool is characterized in that it comprises an annular protrusion that protrudes outward from the projecting portion on the inner peripheral side portion than the protrusion.

  When a metal outer frame member, a metal inner cylinder member, etc. are covered with a resin mantle member, that is, when molded with a resin material, the resin material and each member are not necessarily in close contact with each other, and a fine gap is formed. There may be. In order to prevent the entry of foreign matter into the fine gap described above, the spool is provided with a protruding portion that protrudes toward the outside thereof, thereby complicating the fine gap path described above, in other words, the foreign matter entry path. Things are going to be complicated.

  In the fuel injection valve according to an eighth aspect of the present invention, the spool is provided with an annular protrusion that protrudes outward from the protrusion on the inner peripheral side of the above-described protrusion, that is, on the metal inner cylinder member side. Yes. This annular protrusion serves as a breakwater against the resin that has reached the protrusion of the spool flowing toward the metal inner cylinder member during molding with a resin material.

  As a result, the resin material injected in the molding process of the resin material can be prevented from flowing into the gap between the back side portion of the coil on the inner periphery of the spool and the outer periphery of the metal inner cylinder member. And the positional accuracy between the coil and the metal inner cylinder member can be maintained satisfactorily.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In the following embodiment, an example will be described in which the fuel injection valve according to the present invention is applied to an injector 10 that is mounted on an engine and supplies fuel to a combustion chamber of the engine.

(First embodiment)
FIG. 1 shows a cross-sectional view of an injector 10 according to a first embodiment of the present invention.

  FIG. 2 is an enlarged view of a portion II in FIG.

  FIG. 3 shows an enlarged view of part III in FIG.

  First, the structure of the injector 10 will be described.

  The holder 11 which is a metal inner cylinder member is formed in a cylindrical shape from a magnetic member and a nonmagnetic member. A fuel passage 12 is formed in the holder 11. A needle 30 that is a movable body and a movable core 50 that is a valve member engaged with the needle 30, a valve body 20, a fixed core 40, A spring 13 and an adjusting pipe 14 are accommodated.

  The holder 11 has a first magnetic member 111, a nonmagnetic member 112, and a second magnetic member 113 in this order from the lower valve body 20 side in FIG. The first magnetic member 111 and the nonmagnetic member 112, and the nonmagnetic member 112 and the second magnetic member 113 are coupled by welding. The welding is performed by laser welding, for example. The nonmagnetic member 112 prevents the magnetic flux from being short-circuited between the first magnetic member 111 and the second magnetic member 113. The valve body 20 is fixed to the first non-magnetic member 112 side of the first magnetic member 111 by welding.

  As shown in FIG. 2, the valve body 20 has a nozzle hole plate 21 at the end on the side opposite to the holder 11. The nozzle hole plate 21 is formed in a cup shape and is fixed integrally with the valve body 20 outside the valve body 20. The nozzle hole plate 21 is formed in a thin plate shape and forms a plurality of nozzle holes 22. The nozzle hole 22 may be formed in the valve body 20 instead of being formed in the nozzle hole plate 21. A plate holder 23 that covers the nozzle hole plate 21 is mounted outside the nozzle hole plate 21. The valve body 20 is formed in a cylindrical shape and has a valve seat 24 on the inner peripheral surface. The nozzle hole 22 is disposed on the fuel flow outlet side of the valve seat 24.

  The needle 30 as a movable body is formed in a bottomed cylindrical shape having a fuel passage 31 therein. One end of the needle 30 is press-fitted into the anti-fixed core 40 side of the movable core 50. A seat portion 32 that can be seated on the valve seat 24 formed on the inner peripheral surface of the valve body 20 is formed at the end of the needle 30 on the side of the non-movable core 50. The needle 30 forms a fuel passage 25 between the needle body 30 and the inner peripheral surface of the valve body 20. When the seat portion 32 is seated on the valve seat 24, the communication between the fuel passage 25 and the injection hole 22 is blocked, and fuel is not injected from the injection hole 22.

  The needle 30 has fuel holes 33 and 34 that penetrate the side wall. The fuel that has flowed into the inner peripheral side of the needle 30 flows out to the outer peripheral side of the needle 30 through the fuel holes 33 and 34, and passes through a fuel passage (not shown) formed in the valve body 20 to the fuel passage 25. Flowing. The valve body 20 has a guide portion 26 on the inner peripheral side. The guide portions 26 are formed at a predetermined interval in the circumferential direction of the valve body 20, and a space between the adjacent guide portions 26 serves as a fuel passage (not shown). The inner diameter of the valve body 20 in the guide portion 26 is substantially the same as the outer diameter of the needle 30. Therefore, the needle 30 slides with the guide part 26 of the valve body 20, and the movement in the axial direction is guided by the guide part 26.

  As shown in FIG. 1, the fixed core 40 is formed in a cylindrical shape. The fixed core 40 is fixed to the holder 11 by being press-fitted into the nonmagnetic member 112 and the second magnetic member 113 of the holder 11. The fixed core 40 is installed on the side opposite to the injection hole 22 with respect to the movable core 50 and faces the movable core 50.

  The adjusting pipe 14 is press-fitted inside the fixed core 40. One end of the spring 13 is in contact with the adjusting pipe 14, and the other end is in contact with the movable core 50. The spring 13 biases the seat portion 32 of the needle 30 in the direction in which the seat portion 32 is seated on the valve seat 24 of the valve body 20. The set load of the spring 13 is changed by adjusting the press-fitting amount of the adjusting pipe 14.

  As shown in FIG. 1, a housing 15, which is a metal outer frame member, is disposed on the outer periphery of the holder 11 with a drive coil 64 described later interposed therebetween. The housing 15 is formed from a magnetic member. As shown in FIG. 1, the valve body 20 side portion of the housing 15 is press-fitted into the outer peripheral side of the first magnetic member 111. The counter valve body 20 side portion of the housing 15 surrounds the outer peripheral side of the drive coil 64 as shown in FIG. As shown in FIG. 1, the housing plate 16 is disposed on the outer periphery of the holder 11 with a drive coil 64 described later interposed therebetween. The housing plate 16 is formed from a magnetic member. The housing 15 and the housing plate 16 are magnetically connected to each other and are installed on the outer peripheral side of the coil 61. The fixed core 40, the movable core 50, the first magnetic member 111, the housing 15, the housing plate 16, and the second magnetic member 113 constitute a magnetic circuit.

  The drive coil 64 for operating the magnetic circuit described above, that is, the magnetic circuit composed of the fixed core 40, the movable core 50, the first magnetic member 111, the housing 15, the housing plate 16, and the second magnetic member 113 is energized. The coil 61 is configured to generate an electromagnetic force and a spool 62 around which the coil 61 is wound. As shown in FIG. 1, the spool 62 is formed of a resin material or the like in a hollow cylindrical shape having flanges at both ends. The drive coil 64 is attached to the outer periphery of the holder 11. That is, the holder 11 is inserted into the hole 62 a that is a cylindrical hole of the spool 62. A gap C is formed between the outer peripheral surface of the holder 11 and the inner peripheral surface of the spool 62 as shown in FIG. The coil 61 is electrically connected to the terminal 63. The terminal 63 is connected to an external electric circuit via a connector (not shown). As a result, a drive current is supplied to the coil 61 via the terminal 63.

  The holder 11, needle 30, movable core 50, valve body 20, fixed core 40, housing 15, housing plate 16, spring 13, adjusting pipe 14, and drive coil 64 described above are made of resin as shown in FIG. Covered by the housing 60. That is, after assembling the holder 11, the needle 30, the movable core 50, the valve body 20, the fixed core 40, the housing 15, the housing plate 16, the spring 13, the adjusting pipe 14, and the drive coil 64, they are molded by a resin material. A resin housing 60 is formed. The terminal 63 is also insert-molded at this time.

  Next, the operation of the injector 10 according to the first embodiment of the present invention will be briefly described.

  When no driving current is supplied to the coil 61, no magnetic attractive force is generated between the fixed core 40 and the movable core 50. Therefore, the movable core 50 is moved in the direction away from the fixed core 40, that is, in the direction of the valve body 20 by the urging force of the spring 13. Accordingly, the seat portion 32 of the needle 30 integrated with the movable core 50 is seated on the valve seat 24 of the valve body 20, and fuel injection from the injection hole 22 is stopped.

  When a drive current is supplied to the coil 61, the coil 61 is excited, and a magnetic circuit is formed in the fixed core 40, the movable core 50, the first magnetic member 111, the housing 15, the housing plate 16, and the second magnetic member 113. The As a result, a magnetic attractive force is generated between the fixed core 40 and the movable core 50. When the magnetic attractive force generated between the fixed core 40 and the movable core 50 becomes larger than the urging force of the spring 13, the movable core 50 moves toward the fixed core 40. The movable core 50 moves until it collides with the fixed core 40. Therefore, the needle 30 integrated with the movable core 50 is lifted upward in FIG. As a result, the seat portion 32 of the needle 30 is separated from the valve seat 24 of the valve body 20.

  Foreign matter is removed from the fuel flowing into the fuel passage 12 from above in FIG. 1 of the holder 11 by the filter member 17. The fuel from which foreign matter has been removed passes through the fuel passage 12, the inner peripheral side of the adjusting pipe 14, the inner peripheral side of the fixed core 40, the inner peripheral side of the movable core 50, the fuel passage 31 of the needle 30 and the fuel holes 33 and 34. Then, the fuel is supplied to the fuel passage 25 shown in FIG. When the seat portion 32 is separated from the valve seat 24, the fuel supplied to the fuel passage 25 flows through the opening formed between the seat portion 32 and the valve seat 24 to the injection hole 22 and is injected from the injection hole 22. Is done.

  When the supply of the drive current to the coil 61 is stopped, the magnetic attractive force between the fixed core 40 and the movable core 50 disappears. Therefore, the movable core 50 moves again in the direction away from the fixed core 40 by the urging force of the spring 13. As a result, the seat portion 32 of the needle 30 integrated with the movable core 50 is seated on the valve seat 24 of the valve body 20, and fuel injection from the injection hole 22 is stopped.

  Next, the configuration of the spool 62 of the drive coil 64 and the function and effect, which are the features of the present invention, will be described with reference to FIG.

  The spool 62 includes a ring portion 62b that protrudes to the holder 11 side (right side in FIG. 3) on the end portion 15a side of the housing 15 on the contact portion side. The inner diameter of the ring portion 62 b is set smaller than the hole 62 a and slightly smaller than the outer diameter of the holder 11, specifically, the outer diameter of the first magnetic member 111. Further, as shown in FIG. 3, the axial length of the ring portion 62b is set so that the ring portion 62b does not overlap the coil 61 in the axial direction. That is, a gap is formed between the hole 62a of the spool 62 and the holder 11 as shown in FIG. 3, but the ring portion 62b is lightly press-fitted to the holder 11, and the two are in close contact with each other. And there is no gap. In this case, the press-fitting allowance is set so that the spool 62 can be easily attached to the holder 11 manually. Therefore, the assembly man-hour of the injector 10 does not increase.

  In the step of forming the resin housing 60 by molding the resin material, the resin injected into the mold flows from the upper side to the lower side in FIG. 3, and the contact portion side end portion 15 a of the housing 15 and the spool 62. Reach the gap.

  At this time, since the conventional injector does not have the ring portion 62 b, the gap between the spool 62 and the holder 11 communicates with the gap between the contact portion side end portion 15 a of the housing 15 and the spool 62. For this reason, in the process of forming the resin housing 60, the resin injected into the mold flows into the gap between the spool 62 and the holder 11, and the drive coil 64 is deformed by receiving the pressure of the resin, or the drive coil. There is a possibility that problems such as a decrease in the degree of coaxiality between the holder 64 and the holder 11 may occur.

  On the other hand, in the injector 10 according to the first embodiment of the present invention, the spool 62 is provided with the ring portion 62 b and the ring portion 62 b is in close contact with the holder 11. Thereby, in the molding process of the resin material, the injected resin material can be prevented from flowing into the gap between the inner periphery of the spool 62 and the outer periphery of the holder 11, so that the drive coil 64 in the molding process of the resin material can be prevented. It is possible to provide the injector 10 capable of preventing deformation and lowering of the positional relationship accuracy (such as coaxiality) between the drive coil 64 and the holder 11.

  In addition, in the injector 10 according to the first embodiment of the present invention described above, the fitting between the ring portion 62b and the holder 11 is light press-fitting, and the two are brought into close contact with each other. A gap fit may be formed. In this case, the inner diameter dimension of the ring portion 62b is set to a size that makes it difficult for the resin material to flow into the gap between the ring portion 62b and the holder 11.

(Second Embodiment)
FIG. 4 shows a partially enlarged sectional view of an injector 10 according to the second embodiment of the present invention. FIG. 4 corresponds to an enlarged view of part III in FIG.

  In the injector 10 according to the second embodiment of the present invention, the shape of the spool 62 is changed with respect to the injector 10 according to the first embodiment of the present invention.

  That is, as shown in FIG. 4, the spool 62 includes a cylindrical portion 62 c that extends toward the end portion 15 a (lower side in FIG. 3) on the end portion 15 a side on the contact portion side of the housing 15. . The inner peripheral surface of the cylindrical portion 62 c is formed as an extension of the hole 62 a in the spool 62. That is, the holder 11 is covered with the cylindrical part 62c. Further, as shown in FIG. 4, the tip of the cylindrical portion 62 c is not in contact with the housing 15.

  As shown in FIG. 4, the cylindrical portion 62 c plays a role of narrowing a passage that communicates the clearance space between the contact portion side end portion 15 a of the housing 15 and the spool 62 and the clearance between the spool 62 and the holder 11. Thereby, the resin material injected in the molding process of the resin material can be prevented from flowing into the gap between the inner periphery of the spool 62 and the outer periphery of the holder 11. Therefore, also in the injector 10 according to the second embodiment of the present invention, the injector that can prevent the deformation of the drive coil 64 in the molding process of the resin material and the decrease in the positional relation accuracy (coaxiality, etc.) between the drive coil 64 and the holder 11. 10 can be provided.

(Third embodiment)
FIG. 5 shows a partially enlarged sectional view of an injector 10 according to a third embodiment of the present invention. FIG. 5 corresponds to an enlarged view of part III in FIG.

  In the injector 10 according to the third embodiment of the present invention, the shape of the cylindrical portion 62c of the spool 62 is changed with respect to the injector 10 according to the second embodiment of the present invention.

  That is, as shown in FIG. 5, a ring portion 62 d that protrudes toward the holder 11 (right side in FIG. 5) is provided at the tip of the cylindrical portion 62 c on the end 15 a side of the housing 15. The inner diameter of the ring part 62d is set to be smaller than the hole part 62a and slightly smaller than the outer diameter of the holder 11, more specifically, the outer diameter of the first magnetic member 111. That is, the ring portion 62d is lightly press-fitted into the holder 11, and both are in close contact with each other with no gap. In this case, the press-fitting allowance is set so that the spool 62 can be easily attached to the holder 11 by hand. Therefore, the assembly man-hour of the injector 10 does not increase.

  Thereby, in the molding process of the resin material, the injected resin material can be prevented from flowing into the gap between the inner periphery of the spool 62 and the outer periphery of the holder 11. Therefore, also in the injector 10 according to the third embodiment of the present invention, it is possible to prevent the deformation of the drive coil 64 in the molding process of the resin material and the decrease in the positional relationship accuracy (coaxiality, etc.) between the drive coil 64 and the holder 11. 10 can be provided.

(Fourth embodiment)
FIG. 6 shows a partially enlarged cross-sectional view of an injector 10 according to a fourth embodiment of the present invention. FIG. 5 corresponds to an enlarged view of part III in FIG.

  FIG. 7 shows a cross-sectional view taken along line VII-VII in FIG.

  In the injector 10 according to the fourth embodiment of the present invention, the shape of the spool 62 is changed with respect to the injector 10 according to the first embodiment of the present invention.

  That is, a plurality of convex portions 62d are provided in the hole 62a which is the inner peripheral surface of the spool 62, and three in the fourth embodiment of the present invention as shown in FIG. The convex portion 62d extends in the axial direction of the spool 62, and the length thereof is set so as to cover almost the entire length of the fitting portion between the spool 62 and the holder 11. The three convex parts 62d are arranged at equiangular intervals, that is, 120 degree intervals in the circumferential direction of the hole part 62a. The inscribed circle diameters of the three convex portions 62d are set to be the same as or slightly smaller than the outer diameter of the holder 11.

  With the above-described configuration, when the spool 62 is fitted to the holder 11, the relative movement amount between the spool 62 and the holder 11 in the radial direction of the spool 62 is 0 or very small.

  Thereby, in the molding process of the resin material, the resin injected into the mold flows into the gap between the spool 62 and the holder 11, and even if the pressure of the resin acts on the spool 62, the spool 62 does not move into the holder 11. In contrast, it moves relatively little. Further, there is almost no deformation of the spool 62 itself.

  As described above, also in the injector 10 according to the fourth embodiment of the present invention, it is possible to prevent the deformation of the drive coil 64 in the molding process of the resin material and the decrease in the positional relation accuracy (coaxiality etc.) between the drive coil 64 and the holder 11. An injector 10 can be provided.

  That is, in the injectors 10 according to the first to third embodiments of the present invention described above, all the devices are devised in the shape of the spool 62, and the injected resin material is injected into the spool 62 in the molding process of the resin material. It is prevented from flowing into the gap between the inner periphery and the outer periphery of the holder 11, thereby deforming the drive coil 64 in the molding process of the resin material and reducing the positional relationship accuracy (coaxiality etc.) between the drive coil 64 and the holder 11. Is preventing.

  On the other hand, in the injector 10 according to the fourth embodiment of the present invention, the movement of the spool 62 in the radial direction of the spool 62 in a state in which the spool 62 is fitted to the holder 11 is restricted, and thereby the resin material is molded. The deformation of the drive coil 64 in the molding process and the decrease in positional relationship accuracy (coaxiality, etc.) between the drive coil 64 and the holder 11 are prevented.

  In addition, in the injector 10 by 4th Embodiment of this invention demonstrated above, although the three convex parts 62d are provided, four or more may be sufficient.

  Further, in the injector 10 according to the fourth embodiment of the present invention, the shape of the convex portion 62d is a linear shape having a length in the axial direction of the spool 62. However, the shape is not limited to the linear shape, and the radial direction of the spool 62 As long as the relative movement between the spool 62 and the holder 11 can be prevented, other shapes such as a dot shape may be used. Moreover, you may mix linear and dot shape.

  Further, in the injector 10 according to the fourth embodiment of the present invention, the convex portion is formed on the spool 62, but it may be formed on the outer peripheral surface of the holder 11. Alternatively, both the spool 62 and the holder 11 may be provided.

1 is a cross-sectional view of an injector 10 according to a first embodiment of the present invention. It is the II section in FIG. 1, ie, the enlarged view of the valve seat 24 vicinity. It is the III section enlarged view in FIG. It is an enlarged view of the injector 10 by 2nd Embodiment of this invention. It is an enlarged view of the injector 10 by 3rd Embodiment of this invention. It is an enlarged view of the injector 10 by 4th Embodiment of this invention. It is the VII-VII sectional view taken on the line in FIG.

Explanation of symbols

10 Injector (fuel injection valve)
11 Holder (Metal inner cylinder member)
111 First magnetic member 112 Non-magnetic member 113 Second magnetic member 12 Fuel passage 13 Spring 14 Adjusting pipe 15 Housing (metal outer frame member)
15a End (Abutting part side end)
16 Housing plate 20 Valve body 22 Injection hole 24 Valve seat 30 Needle (movable body)
32 Seat part 40 Fixed core 50 Movable core (valve member)
60 Resin housing 61 Coil 62 Spool 62a Hole 62b Ring 62c Cylinder 62d Ring 62e Convex 63 Terminal 64 Drive coil C Clearance

Claims (8)

A metal inner cylinder member constituting a part of a magnetic circuit for accommodating a movable body and a valve member engaged with the movable body so as to be reciprocally movable in the axial direction and driving the movable body;
A drive coil for operating the magnetic circuit having a coil that generates electromagnetic force when energized and a resin spool around which the coil is wound;
A metal outer frame member disposed on an outer periphery of the metal inner cylinder member with the drive coil interposed therebetween, and a tip portion of the metal inner cylinder member abutting on the metal inner cylinder member so as to be another part of the magnetic circuit;
A resin jacket member that covers at least a part of the outer peripheral surface of the metal outer frame member and is attached to the metal inner cylinder member;
The drive coil is arranged coaxially on the outer periphery of the metal inner cylinder member,
A fuel injection valve in which a gap is formed between an outer peripheral surface of the metal inner cylinder member and an inner peripheral surface of the spool,
The fuel injection valve according to claim 1, wherein the spool includes a ring portion that protrudes toward the metal inner cylinder member at an end of the contact portion side between the metal outer frame member and the metal inner cylinder member.   The fuel injection valve according to claim 1, wherein the ring portion and the metal inner cylinder member are in close contact with each other.   3. The fuel injection valve according to claim 2, wherein the ring portion does not extend to a back side of the coil in the axial direction. A metal inner cylinder member constituting a part of a magnetic circuit for accommodating a movable body and a valve member engaged with the movable body so as to be capable of reciprocating in the axial direction and driving the movable body;
A drive coil for operating the magnetic circuit having a coil that generates electromagnetic force when energized and a resin spool around which the coil is wound;
A metal outer frame member disposed on an outer periphery of the metal inner cylinder member with the drive coil interposed therebetween, and a tip portion of the metal inner cylinder member abutting on the metal inner cylinder member so as to be another part of the magnetic circuit;
A resin jacket member that covers at least a part of the outer peripheral surface of the metal outer frame member and is attached to the metal inner cylinder member;
The drive coil is arranged coaxially on the outer periphery of the metal inner cylinder member,
A fuel injection valve in which a gap is formed between an outer peripheral surface of the metal inner cylinder member and an inner peripheral surface of the spool,
The spool includes a cylindrical portion that extends to the contact portion side at a contact portion side end portion between the metal outer frame member and the metal inner cylinder member and is coaxial with the metal inner cylinder member. Fuel injection valve.   The fuel injection valve according to claim 4, wherein a tip end of the cylindrical portion abuts on the metal outer frame member. A metal inner cylinder member constituting a part of a magnetic circuit for accommodating a movable body and a valve member engaged with the movable body so as to be reciprocally movable in the axial direction and driving the movable body;
A drive coil for operating the magnetic circuit having a coil that generates electromagnetic force when energized and a resin spool around which the coil is wound;
A metal outer frame member disposed on an outer periphery of the metal inner cylinder member with the drive coil interposed therebetween, and a tip portion of the metal inner cylinder member abutting on the metal inner cylinder member so as to be another part of the magnetic circuit;
A resin jacket member that covers at least a part of the outer peripheral surface of the metal outer frame member and is attached to the metal inner cylinder member;
The drive coil is arranged coaxially on the outer periphery of the metal inner cylinder member,
A fuel injection valve in which a gap is formed between an outer peripheral surface of the metal inner cylinder member and an inner peripheral surface of the spool,
A fuel injection valve comprising a plurality of convex portions provided on at least one of an inner peripheral surface of the spool and an outer peripheral surface of the metal inner cylinder member at an insertion portion between the spool and the metal inner cylinder member. A metal inner cylinder member constituting a part of a magnetic circuit for accommodating a movable body and a valve member engaged with the movable body so as to be reciprocally movable in the axial direction and driving the movable body;
A drive coil for operating the magnetic circuit having a coil that generates electromagnetic force when energized and a resin spool around which the coil is wound;
A metal outer frame member disposed on an outer periphery of the metal inner cylinder member with the drive coil interposed therebetween, and a tip portion of the metal inner cylinder member abutting on the metal inner cylinder member so as to be another part of the magnetic circuit;
A resin jacket member that covers at least a part of the outer peripheral surface of the metal outer frame member and is attached to the metal inner cylinder member;
The drive coil is arranged coaxially on the outer periphery of the metal inner cylinder member,
A fuel injection valve in which a gap is formed between an outer peripheral surface of the metal inner cylinder member and an inner peripheral surface of the spool,
The fuel injection valve according to claim 1, wherein the spool is press-fitted in close contact with the metal inner cylindrical member in a portion not extending toward the back side of the coil in the axial direction. A metal inner cylinder member constituting a part of a magnetic circuit for accommodating a movable body and a valve member engaged with the movable body so as to be capable of reciprocating in the axial direction and driving the movable body;
A drive coil for operating the magnetic circuit having a coil that generates electromagnetic force when energized and a resin spool around which the coil is wound;
A metal outer frame member disposed on an outer periphery of the metal inner cylinder member with the drive coil interposed therebetween, and a tip portion of the metal inner cylinder member abutting on the metal inner cylinder member so as to be another part of the magnetic circuit;
A resin jacket member that covers at least a part of the outer peripheral surface of the metal outer frame member and is attached to the metal inner cylinder member;
The drive coil is arranged coaxially on the outer periphery of the metal inner cylinder member,
A fuel injection valve in which a gap is formed between an outer peripheral surface of the metal inner cylinder member and an inner peripheral surface of the spool,
The spool includes a protruding portion that protrudes to the outside,
The fuel injection valve according to claim 1, wherein the spool includes an annular protrusion that protrudes outward from the protrusion at an inner peripheral side of the protrusion.

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