JP2014137038A - Fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel injection valve capable of improving a sealing property while maintaining a physique.SOLUTION: A first needle 20 that can move forward and backward integrally with a movable core has an elastic member 24 that can contact a first valve seat 111 formed on a protrusion 110 of a first cylinder member 11. A second needle 30 provided at a position opposite to the first needle 20 has a valve part 31 that can contact a second valve seat 112 of the protrusion 110. The valve part 31 is formed so that a diameter R2 of a second seal of the valve part 31 and the second valve seat 112 is larger than a diameter R1 of a first seal of the elastic member 24 and the first valve seat 111. When the first needle 20 is separated from the first valve seat 111 by an electromagnetic suction force between the stationary core and the movable core, fuel in a first pressure chamber 26 flows in an intermediate chamber 27. When the second needle 30 is separated from the second valve seat 112 by pressure of the fuel in the second pressure chamber 27, the fuel in the intermediate chamber 27 is injected into a cylinder of an engine through the second pressure chamber 36 and an injection hole 141.

Description

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

  2. Description of the Related Art Conventionally, a fuel injection valve that opens and closes an injection hole formed in a housing to control fuel injection in the housing, and the first valve and the elastic member that the metal members come into contact with or separate from each other and the metal member 2. Description of the Related Art There is known a fuel injection valve that includes a second valve that comes into contact with or is separated from, and has both durability and sealing performance. For example, Patent Document 1 discloses a first valve portion made of a metal member that can contact a first valve seat formed around an injection hole, and a first valve portion formed radially outward of the first valve seat. One needle having a second valve portion made of an elastic member capable of contacting two valve seats is provided, and when the valve is closed, the first valve portion is first after the second valve portion comes into contact with the second valve seat. An electromagnetic fuel injection valve that contacts the valve seat is described.

JP-A-5-6150

  However, in the electromagnetic fuel injection valve described in Patent Document 1, the flow rate of the fuel that can be injected is determined by the diameter of the seal surface between the first valve seat and the first valve portion having a relatively small diameter of the seal surface. The For this reason, the electromagnetic drive force for separating the second valve seat and the second valve portion from each other is larger than the diameter of the seal surface between the first valve seat and the first valve portion. The physique grows.

  The objective of this invention is providing the fuel injection valve which can improve a sealing performance, maintaining a physique.

  The present invention relates to a fuel passage through which fuel supplied to an internal combustion engine flows, a nozzle hole communicating with the fuel passage, a first valve seat provided on the inner wall of the fuel passage, and a second valve seat provided downstream of the first valve seat. , A first needle having an elastic member capable of reciprocating integrally with the movable core in the housing and capable of contacting the first valve seat, and reciprocating separately from the first needle in the housing A fuel injection valve comprising: a second needle that is movably provided and communicates with or shuts off the fuel passage and the injection hole when separated or abutted against the second valve seat; and when the coil generates electromagnetic force, One needle is separated from the first valve seat, and the second needle is separated from the second valve seat after the first needle is separated from the first valve seat.

Two valve seats are formed in the housing of the fuel injection valve of the present invention. Of the two valve seats, a first needle having an elastic member capable of coming into contact with the first valve seat comes into contact with or separates from the first valve seat. Of the two valve seats, a second needle provided separately from the first needle contacts or separates from a second valve seat provided downstream of the first valve seat. When the first needle is separated from the first valve seat by the magnetic attractive force generated between the fixed core and the movable core, the fuel flows between the first needle and the second needle. When the pressure of the fuel flowing between the first needle and the second needle acts on the second needle, the second needle is separated from the second valve seat. Thereby, the fuel in the fuel passage is injected to the outside through the injection hole. As described above, the fuel injection valve according to the present invention is configured so that the first needle and the second needle formed separately are in contact with or separated from the first valve seat and the second valve seat, respectively. Sealability can be improved while having durability.
In addition, since the first needle and the second needle are formed separately, the size of the seal surface between the first needle having the elastic member and the first valve seat is set between the second needle and the second valve seat. It can be determined without being affected by the size of the sealing surface. Thereby, sealing performance can be improved without enlarging the coil which generates the magnetic attraction force which is the driving force of the first needle.

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 which shows the action | operation of the fuel injection valve by 1st Embodiment of this invention. It is sectional drawing of the fuel injection valve by 2nd Embodiment of this invention. It is the IV section enlarged view of FIG. It is sectional drawing which shows the action | operation of the fuel injection valve by 2nd Embodiment of this invention.

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

(First embodiment)
1 to 3 show a fuel injection valve according to a first embodiment of the present invention.

  The fuel injection valve 1 is used, for example, in a fuel injection device of a direct injection gasoline engine (not shown), and directly injects gasoline as fuel into a cylinder of the engine. The fuel injection valve 1 includes a housing 10, a first needle 20, a second needle 30, a movable core 40, a fixed core 50, a coil 60, springs 25 and 35, and the like.

  As shown in FIG. 1, the housing 10 includes a first cylinder member 11, a second cylinder member 12, a third cylinder member 13, an injection nozzle portion 14, a lid portion 15, and the like. The first cylinder member 11, the second cylinder member 12, and the third cylinder member 13 are all formed in a substantially cylindrical shape, and are coaxial in the order of the first cylinder member 11, the second cylinder member 12, and the third cylinder member 13. Are arranged and connected to each other. A fuel passage 18 through which fuel supplied to the engine flows is formed inside the first cylinder member 11, the second cylinder member 12, and the third cylinder member 13.

  The 1st cylinder member 11 and the 3rd cylinder member 13 are formed, for example with magnetic materials, such as ferritic stainless steel, and the magnetic stabilization process is performed. On the other hand, the 2nd cylinder member 12 is formed with nonmagnetic materials, such as austenitic stainless steel, for example.

  The first cylinder member 11 is formed with a protrusion 110 so as to protrude from the inner wall of the first cylinder member 11 in the radial inner direction of the first cylinder member 11. A first valve seat 111 is formed on the second cylindrical member 12 side of the protrusion 110. Further, a second valve seat 112 is formed on the projecting portion 110 on the injection nozzle portion 14 side. As shown in FIG. 2, the first valve seat 111 has an angle α that the first valve seat 111 forms with respect to the central axis φ of the first cylindrical member 11. The two valve seats 112 are formed to be larger than the angle β formed.

  The injection nozzle part 14 is a metal member formed in a substantially cylindrical shape. The injection nozzle portion 14 is accommodated in an opening formed at the end of the first cylinder member 11 opposite to the second cylinder member 12 side. The injection nozzle portion 14 is welded over the entire circumference of the first cylinder member 11 in order to maintain liquid tightness between the fuel passage 18 and the outside of the fuel injection valve 1. The through hole formed in the axial direction of the injection nozzle portion 14 becomes an injection hole 141 through which fuel flowing through the fuel passage 18 is injected into the cylinder of the engine.

  The lid portion 15 is a metal member formed in a substantially cylindrical shape. The lid 15 is fitted into an opening formed at the end of the third cylinder member 13 opposite to the second cylinder member 12 side. In the axial direction of the lid portion 15, a through-hole 151 that communicates the inside and the outside of the housing 10 is formed. The through hole 151 introduces fuel supplied from a fuel tank (not shown) into the housing 10.

  As shown in FIG. 2, the first needle 20 is a metal member that includes a small diameter portion 21, a large diameter portion 22, a shaft portion 23, and the like. The small diameter part 21, the large diameter part 22, and the shaft part 23 are integrally formed. The first needle 20 is accommodated inside the first cylinder member 11 and the second cylinder member 12 so as to be reciprocally movable.

  The small diameter portion 21 is formed in a cylindrical shape. The small diameter portion 21 is formed so that the outer diameter is smaller than the inner diameter of the protrusion 110. When the valve is closed, the small diameter portion 21 is located between the protrusions 110.

  The large diameter portion 22 is formed in a columnar shape, and is provided on the opposite side of the small diameter portion 21 from the injection nozzle portion 14 side. The large diameter portion 22 is formed such that the outer diameter is larger than the outer diameter of the small diameter portion 21. Thereby, a step surface 201 is formed between the small diameter portion 21 and the large diameter portion 22. The step surface 201 is provided with an elastic member 24 that can contact the first valve seat 111.

  The shaft portion 23 is formed in a substantially rod shape, and is provided on the opposite side of the large diameter portion 22 from the injection nozzle portion 14 side. An end portion 232 of the shaft portion 23 opposite to the injection nozzle portion 14 side is connected to the movable core 40. As a result, the first needle 20 can reciprocate integrally with the movable core 40. A through hole 234 is formed in the end portion 232 in the axial direction. A through hole 233 is formed in the end portion 231 of the shaft portion 23 on the injection nozzle portion 14 side substantially perpendicular to the axial direction. The through hole 233 and the through hole 234 communicate with each other in the shaft portion 23.

  The second needle 30 is a metal member that includes a valve portion 31, a shaft portion 32, and the like. The valve portion 31 and the shaft portion 32 are integrally formed. The second needle 30 is provided inside the first cylinder member 11 so as to be reciprocally movable at a position facing the first needle 20.

  The valve part 31 is formed in a substantially hemispherical shape. The spherical surface 311 of the valve portion 31 is formed so as to be able to contact the second valve seat 112. 2, the valve portion 31 has a second seal diameter R2 between the spherical surface 311 and the second valve seat 112 larger than a diameter R1 of the first seal between the elastic member 24 and the first valve seat 111. Is formed.

  The shaft portion 32 is formed in a substantially rod shape, and is provided on the injection nozzle portion 14 side of the valve portion 31. The shaft portion 32 is formed such that its outer diameter is smaller than the maximum outer diameter of the valve portion 31. Thereby, a step surface 301 is formed between the valve portion 31 and the shaft portion 32. One end of the spring 35 abuts on the step surface 301.

  The movable core 40 is a substantially cylindrical member formed from a magnetic material. A through hole 401 is formed in the approximate center of the movable core 40. An end 232 of the shaft portion 23 of the first needle 20 is inserted and fixed in the through hole 401. Thereby, the movable core 40 and the 1st needle 20 can be reciprocated integrally. A concave portion 402 with which one end of the spring 25 abuts is formed on the fixed core 50 side of the movable core 40.

  The fixed core 50 is a substantially cylindrical member formed from a magnetic material. The fixed core 50 is welded to the inside of the third cylindrical member 13 of the housing 10 and is provided to be fixed to the inside of the housing 10.

  The coil 60 is formed in a substantially cylindrical shape, and is provided so as to surround the outer side in the radial direction of the housing 10, particularly the second cylindrical member 12. The coil 60 generates electromagnetic force when electric power is supplied from the outside. When the coil 60 generates electromagnetic force, a magnetic circuit is formed in the fixed core 50, the movable core 40, the first cylindrical member 11, the cylindrical holder 16 provided so as to cover the coil 60, and the third cylindrical member 13. . Thereby, a magnetic attractive force is generated between the fixed core 50 and the movable core 40, and the movable core 40 is attracted to the fixed core 50.

  The spring 25 is provided so that one end is in contact with the inner wall of the recess 402 of the movable core 40. The other end of the spring 25 is in contact with one end of an adjusting pipe 51 that is press-fitted and fixed inside the fixed core 50. The spring 25 has a force that extends in the axial direction. Thereby, the spring 25 urges the first needle 20 together with the movable core 40 toward the first valve seat 111.

  One end of the spring 35 is in contact with the step surface 301 of the second needle 30. The other end of the spring 35 is in contact with the inner wall 142 of the injection nozzle portion 14. The spring 35 has a force extending in the axial direction. As a result, the spring 35 biases the second needle 30 toward the second valve seat 112.

  The fuel introduced from the through hole 151 into the housing 10 includes a through hole 511 formed in the axial direction of the adjusting pipe 51, a through hole 501 formed in the axial direction of the fixed core 50, and the inside of the recess 402. The fuel is injected into the engine cylinder through the through holes 234 and 233 of the first needle 20, the inside of the first cylinder member 11, and the injection hole 141 of the injection nozzle portion 14.

  Next, the manufacturing method of the fuel injection valve 1 is demonstrated based on FIG.

First, the second needle 30 and the spring 35 are assembled to the housing 10. The second needle 30 is inserted into the first cylinder member 11 through an opening in which the injection nozzle portion 14 of the first cylinder member 11 is assembled.
Next, the injection nozzle portion 14 is assembled to the opening of the first cylinder member 11 so that the load of the assembled spring 35 becomes a predetermined load, and the entire circumference is welded.

Next, the first needle 20 is inserted into the housing 10. The first needle 20 is inserted into the housing 10 through an opening in which the lid portion 15 of the third cylindrical member 13 is assembled. After the fixed core 50 is welded to the inside of the third cylindrical member 13, the spring 25 and the adjusting pipe 51 are assembled. At this time, the press-fitting position of the adjusting pipe 51 is adjusted so that the load of the assembled spring 25 becomes a predetermined load.
Finally, the lid 15 is assembled to the third cylinder member 13 to complete the fuel injection valve 1.

Next, the operation of the fuel injection valve 1 will be described with reference to FIGS. 1 and 3. In FIG. 3, an arrow F indicating the direction in which the fuel flows is shown.
Before the coil 60 is energized, that is, when the valve is closed, the fuel introduced into the housing 10 from the through hole 151 passes through the through holes 511 and 501 and the inside of the recess 402 and the through holes 234 and 233 as described above. Then, it flows into the first pressure chamber 26 formed between the inner wall 114 of the first cylinder member 11 and the outer wall 202 on the radially outer side of the first needle 20.

  When the coil 60 is energized, a magnetic attractive force is generated between the fixed core 50 and the movable core 40. When the magnetic attractive force becomes larger than the urging force of the spring 25, the first needle 20 moves to the fixed core 50 side together with the movable core 40, and the elastic member 24 moves away from the first valve seat 111 as shown in FIG. To do. Thus, the fuel in the first pressure chamber 26 passes through the gap formed between the elastic member 24 and the first valve seat 111 that are separated from each other, and the outer wall 203 in the axial direction of the small-diameter portion 21 of the first needle 20. It flows into the intermediate chamber 27 formed between the tip wall 115 of the protrusion 110 of the first cylinder member 11 and the spherical surface 311 of the valve portion 31 of the second needle 30. At this time, the second needle 30 and the second valve seat 112 remain in contact with each other due to the urging force of the spring 35.

  Further, when the fuel flows into the intermediate chamber 27 and the acting force of the fuel in the intermediate chamber 27 acting on the second needle 30 becomes larger than the urging force of the spring 35, the second needle 30 moves to the injection nozzle portion 14 side. . When the second needle 30 moves to the injection nozzle portion 14 side, the spherical surface 311 is separated from the second valve seat 112 as shown in FIG. The fuel in the intermediate chamber 27 passes between the inner wall 116 of the first cylindrical member 11 and the outer wall 302 on the radially outer side of the second needle 30 through a gap formed between the spherical surface 311 and the second valve seat 112. It flows into the formed second pressure chamber 36. The fuel flowing into the second pressure chamber 36 is injected into the cylinder of the engine through the injection hole 141. The fuel injection valve 1 thus functions as an “inner valve”.

  (A) The fuel injection valve 1 according to the first embodiment controls fuel injection by causing the first needle 20 and the second needle 30 to contact or separate from the first valve seat 111 and the second valve seat 112. Since the first needle 20 and the second needle 30 are formed separately, the size of the first valve seat 111 relative to the first needle 20 and the size of the second valve seat 112 relative to the second needle 30 are set independently. can do. Thereby, the magnitude | size of the coil 60 which generate | occur | produces electromagnetic force can be set according to the magnitude | size of the magnetic attraction force which requires. Therefore, the fuel injection valve 1 can have high sealing performance by the elastic member 24 and the first valve seat 111 while maintaining the physique.

(B) The driving force for driving the first needle 20 in the valve opening direction is calculated from the product of the diameter R1 of the first seal and the pressure of the fuel acting in the valve closing direction. In the fuel injection valve 1, the diameter R 1 of the first seal is formed to be smaller than the diameter R 2 of the second seal that determines the amount of fuel that can be injected by the fuel injection valve 1. The force can be relatively small. Thereby, the coil 60 which generate | occur | produces magnetic attraction force can be made small, and the quantity of the electric current sent through the coil 60 can be decreased.
Further, since the fuel injection valve 1 can relatively reduce the driving force of the first needle 20, the lift amount of the first needle 20 can be relatively increased when a current of the same magnitude as before is passed. Thereby, the fuel injection valve 1 can inject a larger amount of fuel.

(C) Further, in the fuel injection valve in which two different valve portions are formed with respect to the two valve seats to achieve both sealing performance and durability, the distance and surface accuracy of the two different valve portions with respect to the two valve seats are reduced. Since it has to be highly managed, it becomes difficult to process the housing forming the valve seat and the needle forming the valve portion.
On the other hand, in the fuel injection valve 1 according to the first embodiment, since the first needle 20 and the second needle 30 are formed separately, the distance and surface accuracy with respect to the valve seat can be managed independently. Thereby, the housing 10, the 1st needle 20, and the 2nd needle 30 which form the 1st valve seat 111 and the 2nd valve seat 112 can be processed easily.

  (D) The elastic member 24 of the first needle 20 is provided at a position relatively away from the engine. Further, a metal second needle 30 and a second valve seat 112 capable of shutting off the in-cylinder gas of the engine are provided between the elastic member 24 and the engine. Thereby, the elastic member 24 becomes difficult to be exposed to high temperature in-cylinder gas. Therefore, the deterioration of the elastic member 24 due to the heat of the in-cylinder gas can be prevented.

  (E) The second pressure chamber 36 or the intermediate chamber 27 formed on the injection nozzle portion 14 side communicates with the cylinder of the engine and is normally at a negative pressure. Further, the first pressure chamber 26 is filled with fuel and has a positive pressure when the valve is closed. The first needle 20 is biased in the direction of the first valve seat 111 by the pressure difference between the second pressure chamber 36 or the intermediate chamber 27 and the first pressure chamber 26. Thereby, the 1st needle 20 and the 1st valve seat 111 can be used as the "self seal" which improves the sealing performance using the pressure of fuel. Therefore, the set load of the spring 25 that urges the first needle 20 toward the first valve seat 111 can be reduced.

  (F) In the first valve seat 111, an angle α formed with respect to the central axis φ of the first cylindrical member 11 is an angle formed by the second valve seat 112 with respect to the central axis φ of the first cylindrical member 11. It is formed to be larger than β. Thereby, when the lift amount of the 1st needle 20 and the 2nd needle 30 is the same, the combination of the 1st needle 20 and the 1st valve seat 111 which the angle formed with respect to the central axis (phi) of the 1st cylinder member 11 is large. A larger gap is formed. As a result, the combination of the first needle 20 and the first valve seat 111 is sufficient for the amount of fuel controlled by the size of the gap formed by the second needle 30 and the second valve seat 112. Fuel can be supplied to the intermediate chamber 27.

  (G) In addition, the fuel injection valve 1 is an inner open valve, and the injection hole 141 is not a part where the first needle 20 and the second needle 30 abut. Thereby, the shape of the nozzle hole 141 can be freely changed.

(Second Embodiment)
Next, the fuel injection valve by 2nd Embodiment of this invention is demonstrated based on FIGS. The second embodiment differs from the first embodiment in the shapes of the first cylindrical member and the second needle. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st Embodiment, and description is abbreviate | omitted.

  The fuel injection valve 2 according to the second embodiment includes a housing 10, a first needle 20, a second needle 70, a movable core 40, a fixed core 50, a coil 60, springs 25 and 75, and the like.

  As shown in FIG. 4, the housing 10 includes a first cylinder member 17, a second cylinder member 12, a third cylinder member 13, a lid portion 15, and the like. The first cylinder member 17 forms a nozzle hole 173. The inner wall of the nozzle hole 173 serves as a second valve seat 172 with which the second needle 70 can come into contact.

  The first cylinder member 17 is formed in a substantially cylindrical shape and is provided at the end of the second cylinder member 12. An injection hole 173 is formed at the end of the first cylinder member 17 opposite to the side connected to the second cylinder member 12. The second valve seat 172, which is the inner wall forming the injection hole 173, is formed so as to form an angle δ with respect to the central axis φ of the first cylindrical member 17. A protrusion 170 is provided on the inner wall of the first cylindrical member 17.

  The projecting portion 170 is formed in an annular shape, and is fixed to the inner wall of the first cylindrical member 17 by, for example, full circumference welding. The surface of the protrusion 170 on the fixed core 50 side is formed so as to be inclined with respect to the central axis φ of the first cylinder member 17, and the first valve seat 171 with which the elastic member 24 of the first needle 20 can abut Become. As shown in FIG. 5, the first valve seat 171 has an angle γ formed by the first valve seat 171 with respect to the central axis φ of the first cylindrical member 17 larger than the angle δ of the second valve seat 172. Is formed.

  The second needle 70 is a metal member composed of a valve portion 71, a shaft portion 72, and the like. The valve portion 71 and the shaft portion 72 are integrally formed. The second needle 70 is accommodated in the first cylindrical member 17 so as to be reciprocally movable.

  The valve portion 71 is formed in a substantially truncated cone shape so that the outside diameter of the fuel injection valve 2 is larger. A conical surface 711 formed on the radially outer side of the valve portion 71 is curved so as to protrude radially outward, and can contact the second valve seat 172. As shown in FIG. 5, in the valve portion 71, the diameter R3 of the second seal between the conical surface 711 and the second valve seat 172 is larger than the diameter R1 of the first seal between the elastic member 24 and the first valve seat 111. It is formed as follows.

  The shaft portion 72 is formed in a substantially rod shape, and is provided on the fixed core 50 side of the valve portion 71. The shaft portion 72 is provided with a substantially annular regulating portion 722 on the outer wall 721 on the radially outer side. One end of the spring 75 is locked to the surface of the restricting portion 722 on the nozzle hole 173 side. The other end of the spring 75 is engaged with an edge 174 of the injection hole 173 on the inner side of the first cylindrical member 17. The spring 75 urges the second needle 70 in a direction in which the second needle 70 abuts on the second valve seat 172.

  In the fuel injection valve 2, when the movable core 40 is attracted to the fixed core 50 by energizing the coil 60, the first needle 20 moves to the fixed core 50 side together with the movable core 40, as shown in FIG. 6 (a). Accordingly, the elastic member 24 is separated from the first valve seat 171. As a result, the fuel in the first pressure chamber 26 flows into the second pressure chamber 76 formed between the inner wall 175 of the first cylinder member 17 and the outer wall 721 of the shaft portion 72 of the second needle 70.

  Further, when the fuel flows into the second pressure chamber 76 and the acting force of the fuel in the second pressure chamber 76 acting on the second needle 70 becomes larger than the urging force of the spring 75, the second needle 70 is moved to the fuel injection valve 2. Move to the outside of the. When the second needle 70 moves to the outside of the fuel injection valve 2, the conical surface 711 is separated from the second valve seat 712 as shown in FIG. 6B, and the fuel in the second pressure chamber 76 passes through the injection hole 173. And injected into the cylinder of the engine. In this way, the fuel injection valve 2 functions as an “outside opening valve”.

  In the fuel injection valve 2 according to the second embodiment, the first needle 20 and the second needle 70 are in contact with or separated from the first valve seat 711 and the second valve seat 712 to control fuel injection. Thereby, the fuel injection valve 2 has the same effects as the effects (a) to (f) of the first embodiment.

(Other embodiments)
(A) In the above-described embodiment, the fuel injection valve injects fuel directly into the cylinder of the direct injection gasoline engine. However, the place where the fuel injection valve injects fuel is not limited to this. A fuel injection valve that injects fuel into an intake manifold that introduces intake air into a cylinder of gasoline may be used.

  (A) In the above-described embodiment, the second seal has a diameter larger than that of the first seal. However, the relationship between the diameter of the first seal and the diameter of the second seal is not limited to this. The diameter of the second seal and the diameter of the first seal may be the same, or the diameter of the second seal may be smaller than the diameter of the first seal.

  (C) In the above-described embodiment, the angle formed by the first valve seat with respect to the central axis of the first cylindrical member is larger than the angle formed by the second valve seat with respect to the central axis of the first cylindrical member. It was formed as follows. However, the relationship between these angles is not limited to this. The angle formed by the first valve seat with respect to the central axis of the first cylindrical member may be the same as or smaller than the angle formed by the second valve seat with respect to the central axis of the first cylindrical member. Good.

  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 ... Fuel injection valve,
10 ・ ・ ・ Housing,
111, 171 ... first valve seat,
112, 172 ... second valve seat,
141, 173... Nozzle holes,
18 ... Fuel passage,
20 ... 1st needle,
24 ... elastic member,
25 ... 1st biasing member,
30, 70 ... second needle,
35, 75 ... second biasing member,
40 ... movable core,
50 ... fixed core,
60: Coil.

Claims (6)

A fuel passage (18) through which fuel flows, an injection hole (141, 173) capable of communicating with the fuel passage, a first valve seat (111, 171) provided on an inner wall of the fuel passage, and a downstream of the first valve seat A housing (10) forming a second valve seat (112, 172) provided on the side;
A coil (60) that generates electromagnetic force when energized;
A fixed core (50) fixed in a magnetic field generated by the coil;
A movable core (40) provided on the nozzle hole side of the fixed core and capable of reciprocating with respect to the fixed core;
A first needle (20) having an elastic member (24) provided in the housing so as to be capable of reciprocating integrally with the movable core and capable of contacting the first valve seat;
A second needle that is provided in the housing so as to be capable of reciprocating separately from the first needle, and shuts off or communicates with the fuel passage and the injection hole when contacting or separating from the second valve seat. 30),
A first biasing member (25) for biasing the first needle in the direction of the first valve seat;
A second biasing member (35) for biasing the second needle in the direction of the second valve seat;
With
When the coil generates electromagnetic force, the first needle is separated from the first valve seat;
The fuel injection valve, wherein the second needle is separated from the second valve seat after the first needle is separated from the first valve seat.   The diameter (R1, R3) of the first seal between the first needle and the first valve seat is the same as the diameter (R2, R4) of the second seal between the second needle and the second valve seat, or The fuel injection valve according to claim 1, wherein the fuel injection valve is smaller than a diameter of the second seal.   The fuel injection valve according to claim 1 or 2, wherein the second valve seat is formed between the first valve seat and the nozzle hole.   The fuel injection valve according to claim 1 or 2, wherein the second valve seat is formed on an inner wall of the nozzle hole.   In the first valve seat, an angle (α, γ) formed with respect to the central axis (φ) of the housing is set to an angle (β, δ) formed by the second valve seat with respect to the central axis of the housing. The fuel injection valve according to any one of claims 1 to 4, wherein the fuel injection valve is larger than the fuel injection valve.   The fuel injection valve according to any one of claims 1 to 5, wherein fuel is directly injected into a cylinder of the internal combustion engine.

Images