JP2018109414A - Fuel injection valve and manufacturing method of fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel injection valve capable of preventing excessive movement of a movable core into a valve closing direction when closing a valve.SOLUTION: A fuel injection valve 1 includes a needle 40 for opening/closing an injection hole 26 for injecting a fuel, a fixing core 27, a movable core 50, a restriction member 35, a first spring 281 and a second spring 282. The movable core 50 comes into contact with the needle 40 when it has moved to the side opposite from the injection hole by a predetermined amount by being sucked by the fixing core 27, and allows the needle 40 to perform a valve opening operation. The restriction member 35 is fixed to the needle 40. The first spring 281 exhibits an energization force for allowing the needle 40 to perform the valve opening operation. The second spring 282 elastically deforms by being sandwiched between the restriction member 35 and the movable core 50, and exhibits an energization force for energizing the movable core 50 to the side opposite from the injection hole. The needle 40 has a large diameter part 412 in which the restriction member 35 is press fitted to the side opposite from the injection hole, and the restriction member 35 is fixed to the needle 40 by being press fitted to the large diameter part 412.SELECTED DRAWING: Figure 2

Description

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

  2. Description of the Related Art Conventionally, a fuel injection valve that opens and closes a nozzle hole of a housing by reciprocating a needle and injects fuel in the housing to the outside is known. For example, in Patent Document 1, a movable core, a fixed core, a coil, and a movable core are provided so as to be capable of reciprocating, and the nozzle hole is opened and closed when separated from the valve seat or in contact with the valve seat according to the movement of the movable core. A fuel injection valve including a needle, a valve closing spring that urges the movable core in the valve closing direction, and a valve opening spring that urges the movable core in the valve opening direction is described.

JP 2012-97728 A

  In the fuel injection valve described in Patent Literature 1, one end of the valve opening spring is in contact with the movable core, and the other end is supported by a support member provided on the housing or the needle. When the fuel injection valve described in Patent Document 1 is closed, if the movable core goes too far in the valve closing direction, the valve-opening spring is compressed more than specified. If the movable core rebounds due to the biasing force of the valve opening spring that is compressed more than specified, the needle may move again in the valve opening direction, and unintended fuel injection may occur.

  An object of the present invention is to provide a fuel injection valve that can prevent the movable core from going too far in the valve closing direction when the valve is closed.

A first aspect of the present invention is a fuel injection valve, which is magnetized with energization of a needle member (411, 711, 412, 42) and a coil (29) for opening and closing an injection hole (26) for injecting fuel. A fixed core (27) that generates a suction force, a movable core (50) that contacts the needle member when the fixed core is sucked by the fixed core and moves to the counter-injection hole side by a predetermined amount, and is fixed to the needle member. A fixed member (35, 65, 75), a first spring (281) that exerts a first elastic force that is elastically deformed in accordance with the valve opening operation of the needle member and performs a valve closing operation of the needle member; A second spring (282) is provided that exerts a second elastic force sandwiched between the movable core and elastically deforming to urge the movable core toward the counter injection hole side. In the fuel injection valve according to the first aspect of the present invention, the needle member has a press-fitting portion (412) into which the fixing member is press-fitted to the side opposite to the injection hole, and the fixing member is press-fitted into the press-fitting portion. It is fixed to the member.
The second aspect of the present invention is a method for manufacturing a fuel injection valve, wherein the second elastic force is adjusted by adjusting the amount of press-fitting into the press-fitting portion of the fixed member.

  The fuel injection valve of the present invention includes a fixing member fixed to the needle member. When the fuel injection valve of the present invention is closed, the movable core moves together with the needle member in the valve closing direction as the nozzle hole direction. The needle member stops moving in the valve closing direction when the nozzle hole is closed, but the movable core further moves in the valve closing direction by inertial force. At this time, the movable core that moves in the valve closing direction comes into contact with the fixed member, and overtravel in the valve closing direction is restricted. Accordingly, it is possible to prevent the needle member from moving in the valve opening direction as the anti-injection hole direction and reopening the injection hole due to the rebound of the movable core that has gone too far in the valve closing direction.

It is sectional drawing of the fuel injection valve by 1st embodiment of this invention. It is the II section enlarged view of FIG. It is sectional drawing of the fuel injection valve by 2nd embodiment of this invention. It is sectional drawing of the fuel injection valve by 3rd embodiment of this invention. It is the VV sectional view taken on the line of FIG. It is sectional drawing of the fuel injection valve by 4th embodiment of this invention. It is sectional drawing of the fuel injection valve by 5th embodiment of this invention. It is sectional drawing of the fuel injection valve by 6th embodiment of this invention. It is sectional drawing of the fuel injection valve by other embodiment of this invention.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
1 and 2 show a fuel injection valve 1 according to a first embodiment of the present invention. 1 and 2 illustrate a valve opening direction in which the needle 40 is separated from the valve seat 255 and a valve closing direction in which the needle 40 is in contact with the valve seat 255.

  The fuel injection valve 1 is used, for example, in a fuel injection device of a direct injection gasoline engine (not shown), and injects and supplies gasoline as fuel to the engine at a high pressure. The fuel injection valve 1 includes a housing 20, a needle 40, a movable core 50, a fixed core 27, a collar housing member 30, a regulating member 35 as a “fixed member”, a coil 29, a first spring 281, a second spring 282, and the like. Prepare.

  As shown in FIG. 1, the housing 20 includes a first cylinder member 21, a second cylinder member 22, a third cylinder member 23, and an injection nozzle 25. The first cylinder member 21, the second cylinder member 22, and the third cylinder member 23 are all cylindrical members. The first cylinder member 21, the second cylinder member 22, and the third cylinder member 23 are arranged so as to be coaxial with each other and are connected to each other.

  The 1st cylinder member 21 and the 3rd cylinder member 23 are formed, for example with magnetic materials, such as ferritic stainless steel, and the magnetic stabilization process is performed. On the other hand, the second cylindrical member 22 is made of a nonmagnetic material such as austenitic stainless steel.

  The injection nozzle 25 is welded to the end of the first cylinder member 21 opposite to the second cylinder member 22. The injection nozzle 25 is a bottomed cylindrical member made of a metal such as martensitic stainless steel. The injection nozzle 25 is subjected to a quenching process so as to have a predetermined hardness. The injection nozzle 25 includes an injection unit 251 and a cylindrical part 252.

The injection unit 251 has a line-symmetric shape with the central axis CA0 of the housing 20 coaxial with the central axis of the fuel injection valve 1 as an axis of symmetry. The outer wall 253 of the injection unit 251 is formed so as to protrude from the inside of the injection nozzle 25 toward the outside. The injection unit 251 has a plurality of injection holes 26 that communicate the inside and the outside of the housing 20. A valve seat 255 is formed around the inner opening of the injection hole 26 on the inner wall 254 of the injection unit 251.
The cylinder part 252 is provided on the radially outer side of the injection part 251 so as to extend in a direction opposite to the direction in which the outer wall 253 of the injection part 251 protrudes. The cylindrical part 252 has one end connected to the injection part 251 and the other end connected to the first cylindrical member 21.

  The needle 40 is made of a metal such as martensitic stainless steel. The needle 40 is subjected to a quenching process so as to have a hardness comparable to that of the injection nozzle 25.

  The needle 40 is accommodated in the housing 20 so as to be reciprocally movable. The needle 40 includes a small diameter portion 411, a large diameter portion 412 as a “press-fit portion”, a seal portion 42, a sliding contact portion 44, a flange portion 43, and the like. The small diameter part 411, the large diameter part 412, the seal part 42, and the flange part 43 are integrally formed. The small diameter portion 411, the large diameter portion 412, the seal portion 42, and the flange portion 43 correspond to a “needle member” described in the claims.

  The small-diameter portion 411 is a rod-like portion provided inside the first cylindrical member 21 so as to be reciprocally movable. A seal portion 42 is provided on the valve seat 255 side of the small diameter portion 411. A large-diameter portion 412 is provided on the opposite side of the small-diameter portion 411 from the valve seat 255. The end of the small diameter portion 411 on the side where the large diameter portion 412 is provided has a flow path 401 through which fuel can flow. The channel 401 communicates with an opening 413 formed so as to penetrate the small diameter portion 411 in the radial direction.

  The large diameter part 412 is a substantially cylindrical part. The outer diameter of the large diameter portion 412 is larger than the outer diameter of the small diameter portion 411. The large-diameter portion 412 has a flow path 402 that communicates with the side opposite to the valve seat 255 of the needle 40 and through which fuel can flow. The channel 402 communicates with the channel 401 of the small diameter portion 411.

  The seal portion 42 is provided so as to be able to contact the valve seat 255. The needle 40 opens and closes the nozzle hole 26 when the seal portion 42 is separated from the valve seat 255 or abuts against the valve seat 255, and communicates or blocks the inside and the outside of the housing 20.

  The sliding contact portion 44 is provided on the seal portion 42 side of the small diameter portion 411. A part of the outer wall 441 is chamfered in the sliding contact portion 44. The slidable contact portion 44 can be slidably contacted with the inner wall of the injection nozzle 25 at a portion of the outer wall 441 that is not chamfered. As a result, the needle 40 is guided to reciprocate at the tip portion on the valve seat 255 side.

  The collar portion 43 is a substantially annular portion. The collar portion 43 is provided on the radially outer side of the end portion of the large diameter portion 412 opposite to the valve seat 255. An end surface 431 on the valve seat 255 side of the collar portion 43 can contact the movable core 50. The end surface 432 of the flange portion 43 opposite to the valve seat 255 is formed to be flush with the end surface 414 of the large diameter portion 412 on the valve seat 255 side.

The movable core 50 is a substantially cylindrical member made of a magnetic material such as ferritic stainless steel. The movable core 50 is provided on the valve seat 255 side of the collar portion 43 so as to be movable relative to the needle 40.
The movable core 50 has an insertion hole 500 through which the large diameter portion 412 is inserted. Further, the movable core 50 has a plurality of communication passages 501 that communicate the opposite side of the movable core 50 from the valve seat 255 and the valve seat 255 side in the radially outward direction of the insertion hole 500. Fuel flows through the communication path 501.
An end surface 502 of the movable core 50 opposite to the valve seat 255 is formed so as to be able to contact the end surface 431 of the flange portion 43 and the fixed core 27. As shown in FIG. 2, when the plate portion 31 of the collar housing member 30 is in contact with the large diameter portion 412 and the collar portion 43 and the cylinder portion 32 of the collar housing member 30 is in contact with the movable core 50. A gap 430 is formed between the end surface 502 and the end surface 431.

  The fixed core 27 is welded to the third cylinder member 23 of the housing 20 and is fixed to the inside of the housing 20. The fixed core 27 has a fixed core main body portion 271 and a fixed core sliding portion 272.

  The fixed core body 271 is made of a magnetic material such as ferritic stainless steel, for example. The fixed core body 271 is subjected to a magnetic stabilization process and is provided in a magnetic field formed by a coil 29 described later.

  The fixed core sliding portion 272 is a cylindrical member provided inside the end portion of the fixed core main body portion 271 on the valve seat 255 side. The fixed core sliding portion 272 is subjected to, for example, chrome plating on the surface, and has a hardness comparable to the hardness of the collar housing member 30, the collar 43, and the movable core 50. As shown in FIG. 2, the fixed core sliding portion 272 is formed such that the end surface 273 on the valve seat 255 side is positioned closer to the valve seat 255 than the end surface 274 on the valve seat 255 side of the fixed core main body portion 271. Thus, when the movable core 50 moves in the valve opening direction, the end surface 502 of the movable core 50 and the end surface 273 of the fixed core sliding portion 272 come into contact with each other, and the movement of the movable core 50 in the valve opening direction is restricted.

  The collar housing member 30 is provided between the first spring 281 and the movable core 50 and on the radially inner side of the fixed core sliding portion 272. The collar part accommodating member 30 is comprised from the board part 31, the cylinder part 32, etc. FIG. The plate part 31 and the cylinder part 32 are integrally formed.

  The plate portion 31 is located on the side opposite to the valve seat 255 with respect to the flange portion 43. The plate portion 31 has an end surface 311 that can contact the end surface 414 of the large diameter portion 412 and the end surface 432 of the flange portion 43. The plate portion 31 has a through hole 312 that penetrates in the direction of the central axis CA0. The through hole 312 communicates the outside and the inside of the collar housing member 30.

The cylindrical portion 32 is a cylindrical portion that is formed so as to extend in the direction of the valve seat 255 from the radially outer end of the plate portion 31. The cylindrical portion 32 is provided such that the inner wall is slidable with the outer wall on the radially outer side of the flange portion 43. Further, the outer wall of the cylindrical portion 32 is formed to be slidable with the inner wall of the fixed core sliding portion 272.
An end surface 321 on the valve seat 255 side of the cylindrical portion 32 is formed so as to be able to contact the end surface 502 of the movable core 50. The cylindrical portion 32 has a length such that the flange 43 can reciprocate inside the flange housing member 30. The cylinder part 32 has a communication path 322 that communicates the inside and the outside of the cylinder part 32. The communication path 322 can communicate with the gap 430.

  The coil 29 is formed in a cylindrical shape and is provided so as to mainly surround the radially outer sides of the second cylinder member 22 and the third cylinder member 23. The coil 29 forms a magnetic field around it when power is supplied. When the magnetic field is formed, a magnetic circuit is formed in the fixed core 27, the movable core 50, the first cylinder member 21, the third cylinder member 23, and the holder 17.

  The first spring 281 is provided so that one end is in contact with the end surface 313 on the opposite side of the valve seat 255 of the plate portion 31. The other end of the first spring 281 is in contact with the end surface 111 on the valve seat 255 side of the adjusting pipe 11 that is press-fitted and fixed inside the fixed core 27. The first spring 281 urges the needle 40 toward the valve seat 255, that is, in the valve closing direction.

  One end of the second spring 282 is in contact with the end surface 503 of the movable core 50 on the valve seat 255 side. The other end of the second spring 282 is supported by the restriction member 35. The second spring 282 biases the movable core 50 on the side opposite to the valve seat 255, that is, in the valve opening direction.

  The urging force as the “second elastic force” of the second spring 282 is set to be smaller than the urging force as the “first elastic force” of the first spring 281. Thereby, when the electric power is not supplied to the coil 29, the seal part 42 of the needle 40 is in a state of being in contact with the valve seat 255, that is, in a closed state.

  The restricting member 35 is a substantially cylindrical member provided on the valve seat 255 side of the flange portion 43 and on the radially outer side of the small diameter portion 411 and the large diameter portion 412. The restricting member 35 is fixed to the needle 40 by press-fitting, for example. The restricting member 35 includes a cylindrical portion 36, an inner protruding portion 37, an outer protruding portion 38, and the like.

  The cylindrical portion 36 is provided on the radially outer side of the small diameter portion 411 and the large diameter portion 412. A communication path 360 is formed between the inner wall 361 of the cylindrical portion 36 and the outer wall 415 of the small diameter portion 411. The communication path 360 communicates the opening 413 of the small diameter portion 411 and the outside of the restriction member 35. An end surface 362 of the cylindrical portion 36 opposite to the valve seat 255 is formed so as to be able to contact the end surface 503 of the movable core 50. An inner edge portion 363 of the cylindrical portion 36 on the valve seat 255 side is formed so as to be separated from a central axis CA0 coaxial with the central axis of the restricting member 35 from the opposite side to the valve seat 255 toward the valve seat 255 side. have.

  The inner projecting portion 37 is provided on the radially inner side of the cylindrical portion 36. The inner projecting portion 37 is formed so as to project in the radially inward direction of the cylindrical portion 36 from the end portion of the cylindrical portion 36 on the side opposite to the valve seat 255. The inner wall 371 of the inner projecting portion 37 is fixed to the outer wall 416 of the large diameter portion 412. An end surface 372 opposite to the valve seat 255 of the inner projecting portion 37 is formed on the same plane as the end surface 362 of the cylindrical portion 36 so as to be able to contact the end surface 503 of the movable core 50.

  The outer projecting portion 38 is formed so as to project outward in the radial direction of the tubular portion 36 from the end portion of the tubular portion 36 on the valve seat 255 side. An end surface 381 opposite to the valve seat 255 of the outer protrusion 38 supports the second spring 282.

  A cylindrical fuel introduction pipe 12 is press-fitted and welded to the end of the third cylinder member 23 opposite to the second cylinder member 22 side. A filter 13 is provided inside the fuel introduction pipe 12. The filter 13 collects foreign matters contained in the fuel that has flowed from the introduction port 14 of the fuel introduction pipe 12.

  The radially outer sides of the fuel introduction pipe 12 and the third cylinder member 23 are molded with resin. A connector 15 is provided in the mold part. The connector 15 is insert-molded with a terminal 16 for supplying power to the coil 29. A cylindrical holder 17 is provided outside the coil 29 in the radial direction so as to cover the coil 29.

  The fuel flowing in from the introduction port 14 of the fuel introduction pipe 12 passes through the inside of the fixed core 27, the inside of the adjusting pipe 11, the through hole 312, the flow paths 402 and 401, the opening 413, the communication path 360, and the first cylinder member 21. It flows between the small diameter portions 411 and is guided into the injection nozzle 25. Further, a part of the fuel flowing inside the adjusting pipe 11 flows between the communication path 501, the first cylinder member 21 and the regulating member 35, and is guided into the injection nozzle 25. That is, a portion from the inlet 14 of the fuel introduction pipe 12 to the space between the first cylindrical member 21 and the small diameter portion 411 serves as a fuel passage 18 for introducing fuel into the injection nozzle 25.

Next, the operation of the fuel injection valve 1 will be described.
When power is not supplied to the coil 29, the seal portion 42 of the needle 40 is in contact with the valve seat 255. At this time, the needle 40, the movable core 50, and the collar housing member 30 are in the positional relationship shown in FIG. Specifically, since no magnetic attractive force is generated between the fixed core 27 and the movable core 50, a gap is formed between the fixed core 27 and the movable core 50. Further, since the large-diameter portion 412 and the flange portion 43 are in contact with the plate portion 31 and the cylindrical portion 32 and the movable core 50 are in contact, a gap 430 is formed. The gap 430 is filled with fuel flowing through the fuel passage 18.

  When electric power is supplied to the coil 29 and a magnetic attraction force is generated between the fixed core 27 and the movable core 50, the movable core 50 has an urging force of the first spring 281, an urging force of the second spring 282, and the magnetic force. The distance corresponding to the length of the gap 430 in the direction of the central axis CA0 is accelerated in accordance with the balance of the suction force, and moves in the valve opening direction, so that the end surface 502 of the movable core 50 contacts the end surface 431 of the flange 43. At this time, the fuel in the gap 430 quickly flows out of the flange housing member 30 via the communication path 322 of the cylindrical portion 32.

  Further, the movable core 50 moves in the valve opening direction while the end surface 502 of the movable core 50 and the end surface 431 of the flange portion 43 are in contact with each other. As a result, the seal portion 42 is separated from the valve seat 255 and the nozzle hole 26 is opened. When the injection hole 26 is opened, the fuel guided to the inside of the injection nozzle 25 is injected outside through the injection hole 26. When the movable core 50 moving in the valve opening direction comes into contact with the fixed core sliding portion 272, the movement of the movable core 50 in the valve opening direction stops.

  When the supply of power to the coil 29 is stopped, the magnetic attractive force generated between the fixed core 27 and the movable core 50 disappears, so that the movable core 50 and the collar housing member 30 are connected to the first spring 281. The valve moves in the valve closing direction according to the urging force and the urging force of the second spring 282. When the movable core 50 and the collar housing member 30 move in the valve closing direction, the end surface 414, the end surface 431, and the end surface 311 come into contact with each other. As a result, the needle 40 moves in the valve closing direction together with the movable core 50 and the collar housing member 30.

  When the needle 40 moves in the valve closing direction and the seal portion 42 and the valve seat 255 come into contact with each other, the nozzle hole 26 is closed, and fuel injection is completed. When the seal portion 42 and the valve seat 255 come into contact with each other, the needle 40 stops moving in the valve closing direction, but the movable core 50 moves in the valve closing direction due to inertial force. At this time, the moving speed of the movable core 50 in the valve closing direction gradually decreases due to the urging force of the second spring 282, but if the moving speed does not sufficiently slow, the movable core 50 has the end surface 362 of the regulating member 35. , 372, the movement in the valve closing direction is stopped.

The fuel injection valve 1 according to the first embodiment includes a regulating member 35 that can contact the movable core 50 while supporting the second spring 282.
When the opened fuel injection valve 1 is closed, the movable core 50 and the needle 40 move together in the valve closing direction. The movable core 50 further moves in the valve closing direction even after the needle 40 abuts on the valve seat 255 and stops moving in the valve closing direction. The restricting member 35 is provided so that the movable core 50 can be reciprocated between the restriction member 35 and the needle 40 to prevent the movable core 50 from going too far in the valve closing direction after the needle 40 abuts the valve seat 255. To do. Accordingly, it is possible to prevent the needle 40 from moving in the valve opening direction due to the rebound of the movable core 50 that has gone too far in the valve closing direction, and the nozzle hole 26 to be opened again.

  The regulating member 35 is provided on the radially outer side of the small diameter portion 411 and the large diameter portion 412 and supports one end of the second spring 282. As a result, the biasing force of the second spring 282 can be adjusted by adjusting the distance between the restricting member 35 and the movable core 50 when the fuel injection valve 1 is manufactured. Can be adjusted.

Conventionally, adjustment of the urging force of the urging member that urges the movable core in the valve opening direction at the time of manufacturing the fuel injection valve is performed by adjusting the urging member, the needle, the movable core, etc. to a housing that supports one end of the urging member. It was done in the state that assembled. For this reason, adjustment of the urging force of the urging member is relatively difficult, and the number of man-hours necessary for adjustment has increased.
In the fuel injection valve 1, the urging force of the second spring 282 can be adjusted only by the relationship between the regulating member 35 and the movable core 50. As a result, the biasing force can be adjusted relatively easily as compared with the case where one end of the biasing means for biasing the movable core in the valve opening direction is supported by the housing.

  Further, in the fuel injection valve 1, since the urging force of the second spring 282 can be adjusted in the needle assembling process for assembling the movable core 50 and the needle 40, the urging member, the needle, the movable core, etc. are assembled to the housing. Thereafter, an injector assembling step for adjusting the urging force of the urging member becomes unnecessary. Thereby, the manufacturing man-hour of a fuel injection valve can be reduced.

  Between the inner wall 361 of the cylindrical part 36 and the outer wall 415 of the small diameter part 411, a communication path 360 constituting the fuel path 18 is formed. As a result, an amount of fuel necessary for fuel injection can surely flow from the inlet 14 of the fuel introduction pipe 12 to the inside of the injection nozzle 25.

  An inner edge portion 363 of the cylindrical portion 36 on the valve seat 255 side is formed so as to be separated from a central axis CA0 coaxial with the central axis of the restricting member 35 from the opposite side to the valve seat 255 toward the valve seat 255 side. have. Thereby, the fuel can smoothly flow out from the communication path 360 to the outside of the regulating member 35.

  In the restricting member 35, an inner projecting portion 37 provided at an end portion of the cylindrical portion 36 opposite to the valve seat 255 is press-fitted into the large diameter portion 412 and fixed. Thereby, when the fuel injection valve 1 is closed, an impact force when the movable core 50 moving in the valve closing direction collides with the regulating member 35 can be received by the inner projecting portion 37. Therefore, it is possible to prevent the restricting member 35 from being damaged by an impact force when the movable core 50 collides with the restricting member 35.

  In the fuel injection valve 1, when the valve is opened, the movable core 50 moves in the valve opening direction while accelerating a distance corresponding to the length of the gap 430 in the direction of the central axis CA0. In the movable core 50, the end surface 502 of the movable core 50 abuts on the end surface 431 of the flange portion 43 in a state of being accelerated to some extent. Thereby, in the fuel injection valve 1, a relatively large force in the valve opening direction can be applied to the needle 40.

(Second embodiment)
Next, the fuel injection valve by 2nd embodiment of this invention is demonstrated based on FIG. The second embodiment is different from the first embodiment in that a narrow space having a relatively small cross-sectional area is provided between the regulating member and the housing. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st embodiment, and description is abbreviate | omitted. FIG. 3 illustrates a valve opening direction in which the needle 40 is separated from the valve seat 255 and a valve closing direction in which the needle 40 is in contact with the valve seat 255.

  In the fuel injection valve 2 according to the second embodiment, the first cylinder member 21 has a flow path having a relatively small cross-sectional area on the valve seat 255 side of the outer protrusion 38 of the regulating member 35. Specifically, as shown in FIG. 3, a gap 380 is formed between the end surface 382 of the outer protrusion 38 on the valve seat 255 side and the inner wall 211 of the first cylindrical member 21 facing the end surface 382.

  In the fuel injection valve 2, when the needle 40 moves in the valve closing direction, the gap 380 gradually narrows, so that a damper effect is generated by the fuel in the gap 380. This damper effect slows down the moving speed of the needle 40 in the valve closing direction, and prevents the needle 40 from colliding with the valve seat 255 at a relatively high speed. Thereby, 2nd embodiment can prevent that the seal | sticker part 42 and the valve seat 255 are damaged by the collision with the seal | sticker part 42 and the valve seat 255 at the time of valve closing.

(Third embodiment)
Next, the fuel injection valve by 3rd embodiment of this invention is demonstrated based on FIG. The third embodiment is different from the first embodiment in the shape of the regulating member. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st embodiment, and description is abbreviate | omitted. FIG. 4 shows a valve opening direction in which the needle 40 is separated from the valve seat 255 and a valve closing direction in which the needle 40 is in contact with the valve seat 255.

  The fuel injection valve 3 according to the third embodiment includes a regulating member 65 as a “fixing member”. The regulating member 65 is fixed to the needle 40 by press-fitting and laser welding, for example. The restricting member 65 includes a cylindrical portion 66, an outer protruding portion 38, and the like.

  The cylindrical portion 66 is provided on the radially outer side of the small diameter portion 411 and the large diameter portion 412. The inner wall at the end opposite to the valve seat 255 of the inner wall 661 of the cylindrical portion 66 is fixed to the outer wall 416 of the large diameter portion 412. The inner wall of the end portion on the valve seat 255 side of the inner wall 661 of the cylindrical portion 66 is welded to the outer wall 415 of the small diameter portion 411 by laser welding. An end surface 662 of the cylindrical portion 66 opposite to the valve seat 255 is formed so as to be able to contact the end surface 503 of the movable core 50.

  The cylindrical portion 66 has a plurality of communication holes 664 that penetrate in the radial direction. As illustrated in FIG. 5, the communication hole 664 is formed at a position corresponding to the opening 413 of the small diameter portion 411. The communication hole 664 communicates the opening 413 and the outside of the restriction member 65.

  In the fuel injection valve 3, the end of the regulating member 65 opposite to the valve seat 255 is fixed to the large diameter portion 412, and the end on the valve seat 255 side is laser welded to the small diameter portion 411. The regulating member 65 whose both ends are fixed to the needle 40 has a communication hole 664 that communicates the opening 413 and the outside of the regulating member 65. The communication hole 664 constitutes the fuel passage 18, and the fuel flowing between the opening 413 and the outside of the regulating member 65 passes therethrough. As a result, an amount of fuel necessary for fuel injection can surely flow from the inlet 14 of the fuel introduction pipe 12 to the inside of the injection nozzle 25.

  Further, the regulating member 65 has an end on the valve seat 255 side fixed to the small diameter portion 411 by laser welding. Thereby, when the fuel injection valve 3 is closed, the restricting member 65 is prevented from moving in the valve closing direction by the impact force when the movable core 50 moving in the valve closing direction collides with the restricting member 35. Therefore, it is possible to prevent the biasing force of the second spring 282 from changing due to the use of the fuel injection valve 3.

(Fourth embodiment)
Next, the fuel injection valve by 4th embodiment of this invention is demonstrated based on FIG. The fourth embodiment differs from the first embodiment in the shapes of the needle and the regulating member. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st embodiment, and description is abbreviate | omitted. FIG. 6 illustrates a valve opening direction in which the needle 70 is separated from the valve seat 255 and a valve closing direction in which the needle 70 is in contact with the valve seat 255.

The fuel injection valve 4 according to the fourth embodiment includes a needle 70 and a regulating member 75 as a “fixing member”.
The needle 70 includes a small diameter portion 711, a large diameter portion 412, a seal portion 42, a sliding contact portion 44, a flange portion 43, and the like. The small diameter part 711, the large diameter part 412, the seal part 42, and the flange part 43 are integrally formed. The small-diameter portion 411, the large-diameter portion 412 and the seal portion 42 correspond to a “needle member” described in the claims.

  The small-diameter portion 711 is a rod-like portion provided inside the first cylinder member 21 so as to be reciprocally movable. A seal portion 42 is provided on the valve seat 255 side of the small diameter portion 711. A large-diameter portion 412 is provided on the opposite side of the small-diameter portion 711 from the valve seat 255. The end of the small diameter portion 711 on the side where the large diameter portion 412 is provided has a flow path 701 through which fuel can flow. The channel 701 is formed to be longer in the central axis CA0 direction than the channel 401 of the first embodiment. The channel 701 communicates with the channel 402. The channel 701 communicates with an opening 713 formed so as to penetrate the small diameter portion 711 in the radial direction. As shown in FIG. 6, the opening 713 is formed on the valve seat 255 side from the regulating member 75.

  The restricting member 75 is fixed to the needle 40 by press-fitting, for example. The restricting member 75 includes a cylindrical portion 76, an outer protruding portion 38, and the like.

  The cylindrical portion 76 is provided on the radially outer side of the small diameter portion 411 and the large diameter portion 412. The inner wall at the end opposite to the valve seat 255 of the inner wall 761 of the cylindrical portion 76 is fixed to the outer wall 416 of the large diameter portion 412. A gap 760 is formed between the inner wall at the end on the valve seat 255 side of the inner wall 761 of the cylindrical portion 76 and the outer wall 715 of the small diameter portion 711. The gap 760 has an opening 764 on the valve seat 255 side. Fuel can flow into or out of the gap 760. An end surface 762 opposite to the valve seat 255 of the cylindrical portion 76 is formed so as to be able to contact the end surface 503 of the movable core 50. The inner edge portion 763 on the valve seat 255 side of the cylindrical portion 76 has an inclined surface formed so as to be separated from the central axis CA0 as it goes from the side opposite to the valve seat 255 toward the valve seat 255 side.

  In the fuel injection valve 4, the opening 713 of the needle 70 constituting the fuel passage 18 is formed on the valve seat 255 side with respect to the regulating member 75. As a result, the fuel injection valve 4 can reliably flow an amount of fuel necessary for fuel injection to the inside of the injection nozzle 25 without being obstructed by the regulating member 75.

  In the fuel injection valve 4, when the needle 70 moves in the valve closing direction, the fuel is pushed into the gap 760 through the space between the inner edge portion 763 of the regulating member 75 and the outer wall 715 of the small diameter portion 711. By pushing the fuel into the gap 760, an appropriate resistance acts on the needle 70, and the moving speed of the needle 70 in the valve closing direction becomes relatively slow. Thereby, it is possible to prevent the needle 70 from colliding with the valve seat 255 at a high speed. Therefore, the fourth embodiment can prevent the seal portion 42 and the valve seat 255 from being damaged by the collision between the seal portion 42 and the valve seat 255 when the valve is closed.

  Further, the inner edge portion 763 on the valve seat 255 side of the cylindrical portion 76 that forms the gap 760 has an inclined surface that is formed so as to move away from the central axis CA0 from the opposite side to the valve seat 255 toward the valve seat 255 side. doing. Thereby, the inflow and outflow of fuel to the gap 760 can be performed smoothly.

(Fifth embodiment)
Next, the fuel injection valve by 5th embodiment of this invention is demonstrated based on FIG. The fifth embodiment is different from the fourth embodiment in that a movement blocking portion for blocking the movement of the regulating member is provided. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 4th embodiment, and description is abbreviate | omitted. FIG. 7 illustrates a valve opening direction in which the needle 70 is separated from the valve seat 255 and a valve closing direction in which the needle 70 is in contact with the valve seat 255.

  The fuel injection valve 5 according to the fifth embodiment includes a movement preventing unit 80. The movement preventing portion 80 is an annular member, and is fixed to the outer wall 715 of the small diameter portion 711 by welding, for example, on the valve seat 255 side of the regulating member 75. The movement prevention unit 80 is in contact with the end surface 382 of the outer protrusion 38 of the regulating member 75.

  In the fuel injection valve 5, the movement preventing unit 80 can prevent the restricting member 75 from moving in the valve closing direction due to an impact force when the movable core 50 moving in the valve closing direction collides with the restricting member 75. . Thereby, the relative position of the regulating member 75 with respect to the movable core 50 via the needle 70 defining the urging force of the second spring 282 can be made unchanged.

(Sixth embodiment)
Next, the fuel injection valve by 6th embodiment of this invention is demonstrated based on FIG. The sixth embodiment is different from the first embodiment in that a gap is formed between the flange portion and the movable core and between the flange portion and the plate portion when the valve is closed. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st embodiment, and description is abbreviate | omitted. FIG. 8 illustrates a valve opening direction in which the needle 40 is separated from the valve seat 255 and a valve closing direction in which the needle 40 is in contact with the valve seat 255.

  A sectional view of the fuel injection valve 6 according to the sixth embodiment is shown in FIG. In the state shown in FIG. 8, the seal portion 42 and the valve seat 255 are in contact with each other. At this time, the cylindrical portion 32 and the movable core 50 are in contact with each other, and the movable core 50 and the regulating member 35 are in contact with each other. Further, the end surface 431 on the valve seat 255 side of the flange portion 43 forms a gap 430 with the end surface 502, while the end surface 432 on the opposite side of the valve seat 255 of the flange portion 43 corresponds to the flange portion accommodating member 30. A gap 310 is formed between the end surface 311 of the plate portion 31.

  In the sixth embodiment, when a magnetic attractive force is generated between the fixed core 27 and the movable core 50 from the state shown in FIG. 68, the movable core 50 has a distance corresponding to the length of the gap 430 in the central axis CA0 direction. Moving in the valve opening direction while accelerating, the end surface 502 of the movable core 50 contacts the end surface 431 of the flange 43. Thereby, in the fuel injection valve 6, a relatively large force in the valve opening direction can be applied to the needle 40.

(Other embodiments)
(1) In the fuel injection valve according to the above-described embodiment, when the plate portion of the collar housing member is in contact with the needle and the cylinder portion of the collar housing member is in contact with the movable core, the valve seat of the movable core It is assumed that there is a gap between the end face on the opposite side to the end face on the valve seat side of the flange. However, the fuel injection valve which does not have the said clearance gap may be sufficient. FIG. 9 shows a fuel injection valve 7 that is not provided with a flange housing member. In the fuel injection valve 7, the end surface 431 of the flange portion 43 and the end surface 502 of the movable core 50 are in contact with each other when the seal portion 42 and the valve seat 255 are in contact with each other. Even with such a fuel injection valve 7, the restriction member 35 that supports the second spring 282 can prevent the movable core 50 from rebounding by including the restriction member of the present invention.

  (2) In the above-described embodiment, the needle has the “fuel channel”. The fuel flow path may not be provided.

  (3) In the above-described embodiment, the regulating member has the cylindrical portion and the outer protruding portion. However, the shape of the regulating member is not limited to this. The movable core may be provided so as to be movable between the flange portion on the valve seat side of the flange portion, and may have a “support portion” and a “contact portion” that can contact the movable core.

  (4) In the first and second embodiments, the end surface on the opposite side to the valve seat of the inner protruding portion and the end surface on the opposite side to the valve seat of the cylindrical portion are located on the same plane. However, it does not have to be on the same plane. It is only necessary that at least one of the end surface opposite to the valve seat of the inner projecting portion or the end surface opposite to the valve seat of the cylindrical portion is formed so as to be able to contact the movable core when moving in the direction of the movable core thumbtack valve. .

  (5) In the first and second embodiments, the “end portion on the movable core side” of the restricting member is press-fitted and fixed to the large-diameter portion. However, the portion where the regulating member is press-fitted and fixed is not limited to this.

  (6) In the fifth embodiment, the movement prevention unit is a single annular member. However, the shape and number of the movement blocking portions are not limited to this. The movement blocking part is composed of a plurality of arc-shaped members, and may be provided, for example, at equal intervals in the circumferential direction on the outer wall of the small diameter part. In this case, the “damper space” formed between the outer wall of the small-diameter portion of the needle and the inner wall of the restricting member communicates with the outside of the restricting member via the gap between adjacent movement preventing portions, so that the fuel can be smoothly supplied. It can flow.

  (7) The fuel injection valve according to the fourth and fifth embodiments may have a “narrow space” formed between the end face of the regulating member on the valve seat side and the inner wall of the housing facing the end face.

  (8) The fuel injection valve according to the first to third embodiments may include a movement blocking unit. In this case, the movement blocking portion is formed of a plurality of arc-shaped members, and thus the communication path formed between the outer wall of the small-diameter portion of the needle and the inner wall of the regulating member is a gap between the adjacent movement blocking portions. In this way, the fuel can flow smoothly.

  As mentioned above, this invention is not limited to such embodiment, It can implement with a various form in the range which does not deviate from the summary.

1, 2, 3, 4, 5, 7 ... fuel injection valve 26 ... injection hole 27 ... fixed core 29 ... coil 35, 65, 75 ... regulating member (fixing member)
42 ... Sealing part (needle member)
50 ... movable core 281 ... first spring 282 ... second spring 411, 711 ... small diameter part (needle member)
412 ... Large diameter part (needle member, press-fit part)

Claims (2)

Needle members (411, 711, 412, 42) for opening and closing the nozzle holes (26) for injecting fuel;
A fixed core (27) that generates a magnetic attractive force when energized to the coil (29);
A movable core (50) that contacts the needle member when it is sucked by the fixed core and moves a predetermined amount toward the counter-injection hole, and opens the needle member;
A fixing member (35, 65, 75) fixed to the needle member;
A first spring (281) that exerts a first elastic force that is elastically deformed in accordance with the valve opening operation of the needle member and performs the valve closing operation of the needle member;
A second spring (282) that is sandwiched between the fixed member and the movable core and elastically deforms and exerts a second elastic force that biases the movable core toward the counter-injection hole;
With
The needle member has a press-fitting portion (412) into which the fixing member is press-fitted to the anti-injection hole side,
The fuel injection valve, wherein the fixing member is fixed to the needle member by being press-fitted into the press-fitting portion. Needle members (411, 711, 412, 42) for opening and closing the nozzle holes (26) for injecting fuel;
A fixed core (27) that generates a magnetic attractive force when energized to the coil (29);
A movable core (50) that contacts the needle member when it is sucked by the fixed core and moves a predetermined amount toward the counter-injection hole, and opens the needle member;
A fixing member (35, 65, 75) fixed to the needle member;
A first spring (281) that exerts a first elastic force that is elastically deformed in accordance with the valve opening operation of the needle member and performs the valve closing operation of the needle member;
A second spring (282) that is sandwiched between the fixed member and the movable core and elastically deforms and exerts a second elastic force that biases the movable core toward the counter-injection hole;
With
The needle member has a press-fitting portion (412) into which the fixing member is press-fitted to the anti-injection hole side,
The fixing member is a method of manufacturing a fuel injection valve fixed to the needle member by being press-fitted into the press-fitting portion,
A method for manufacturing a fuel injection valve, wherein the second elastic force is adjusted by adjusting an amount of press-fitting of the fixing member into the press-fitting portion.

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