JP5464167B2 - Fuel injection valve - Google Patents

Description

  The present invention relates to a fuel injection valve that directly injects gaseous fuel into a combustion chamber of an internal combustion engine.

  2. Description of the Related Art Conventionally, a fuel injection valve for gaseous fuel arranged in an intake system of an internal combustion engine is known (for example, see Patent Document 1). And since the fuel fuel is not easier to prevent leakage than the liquid fuel, this fuel injection valve is provided with a resin seal member on a reciprocating metal needle, and the seat member of the seal member and the metal valve body. Is opened and closed to open and close the fuel passage to ensure sealing performance when the valve is closed.

Japanese Patent Application Laid-Open No. 11-303685

  However, when the above-described conventional fuel injection valve is used for direct injection, there is a problem that the resin seal member is melted by the heat of the high-temperature combustion gas.

  Therefore, it is conceivable to eliminate the resin seal member and form a metal sheet portion on the needle. However, gas fuel has a low viscosity and a small molecular size, so leakage occurs even in small gaps. End up. In order to prevent this leakage, it is only necessary to increase the processing accuracy of the sheet portion to make the gap as small as possible. However, there arises a problem that the processing cost becomes very high.

  The present invention has been made in view of the above points, and an object of the present invention is to prevent melting damage of a resin seal member in a fuel injection valve that directly injects gaseous fuel into a combustion chamber of an internal combustion engine.

In order to achieve the above object, in the first and seventh aspects of the present invention, the metal needle (23) having a fuel passage (27, 230, 231, 240, 250) through which gaseous fuel flows and reciprocating is provided. A fuel injection valve that opens and closes a fuel passage by contacting and separating from a metal valve body (24) and directly injects gaseous fuel into the combustion chamber (13) of the internal combustion engine when the valve is opened. A seal member (28) is provided, and a downstream needle seat portion (232) is formed on the downstream side of the fuel flow with respect to the seal member. When the body seat portion (241) and the downstream body seat portion (242) that opens and closes the fuel passage by contact with and separation from the downstream needle seat portion are formed, and when the valve opening state is shifted to the valve closing state, After the seal member and the upstream body seat portion abut, the downstream needle seat portion and the downstream body seat portion abut on each other.

  According to this, good sealing performance at the time of valve closing is ensured by the upstream valve portion constituted by the resin seal member and the upstream body seat portion. Further, since the high-temperature combustion gas is prevented from flowing to the upstream valve portion by closing the downstream valve portion composed of the downstream needle seat portion and the downstream body seat portion, a resin seal member It is possible to prevent melting damage. That is, it is possible to ensure both good sealing performance when the valve is closed and prevention of melting damage of the resin seal member.

  In addition, when the valve is closed, the resin seal member exerts the function of a damper to reduce the collision speed between the downstream needle seat part and the downstream body seat part, thereby preventing or suppressing wear of those seat parts. can do.

  Furthermore, in the valve-closed state, the downstream valve portion functions as a stopper and the deformation amount of the resin seal member can be regulated, so that deterioration of the resin seal member can be prevented or suppressed.

According to the second and eighth aspects of the present invention, the metal needle (23) including the fuel passage (27, 230, 231, 240, 250) through which the gaseous fuel circulates and the reciprocating metal valve body (24) is provided. ) To open and close the fuel passage, and when the valve is opened, the fuel injection valve directly injects gaseous fuel into the combustion chamber (13) of the internal combustion engine. The valve body has a resin sealing member (28). A downstream body seat portion (242) is formed on the downstream side of the fuel flow with respect to the seal member, and an upstream needle seat portion that opens and closes the fuel passage by contact with and separation from the seal member, and the downstream side A downstream needle seat portion (232) that opens and closes the fuel passage by contact with and separation from the body seat portion is formed, and the seal member and the upstream needle seat portion are moved when the valve opening state is shifted to the valve closing state. After the contact, the downstream needle seat portion and the downstream body seat portion are configured to contact each other.

  According to this, good sealing performance when the valve is closed is ensured by the upstream valve portion constituted by the resin seal member and the upstream needle seat portion. Further, since the high-temperature combustion gas is prevented from flowing to the upstream valve portion by closing the downstream valve portion composed of the downstream needle seat portion and the downstream body seat portion, a resin seal member It is possible to prevent melting damage. That is, it is possible to ensure both good sealing performance when the valve is closed and prevention of melting damage of the resin seal member.

  In addition, when the valve is closed, the resin seal member exerts the function of a damper to reduce the collision speed between the downstream needle seat part and the downstream body seat part, thereby preventing or suppressing wear of those seat parts. can do.

  Furthermore, in the valve-closed state, the downstream valve portion functions as a stopper and the deformation amount of the resin seal member can be regulated, so that deterioration of the resin seal member can be prevented or suppressed.

As in the invention according to claim 3, 7, are opposed to the needle and the valve body (24) at one axial end of the two Doru (23), the sealing member (28) and the respective seat, and the needle An upstream valve portion that is located on a surface facing the valve body and includes a seal member and an upstream body seat portion (241), and a downstream needle seat portion (232) and a downstream body seat portion (242) Can be arranged concentrically.

As in the invention according to claim 4, 8, are opposed to the needle and the valve body (24) at one axial end of the two Doru (23), the sealing member (28) and the respective seat, and the needle It is located on the surface facing the valve body, and is composed of an upstream valve portion composed of a seal member and an upstream needle seat portion, and a downstream needle seat portion (232) and a downstream body seat portion (242). The downstream valve portion can be arranged concentrically.

In the invention described in claim 5, 9, on the inner peripheral side and outer peripheral side of the sheet seal member (28), the relief space Deformable seal member when the valve is closed (233, 234) is formed It is characterized by that.

  According to this, since the resin seal member can be easily deformed when the valve is closed, the downstream needle seat portion (232) and the downstream body seat portion can be reliably brought into contact with a small force. it can.

In the invention described in claim 6, 7, 8, on the lower stream side body seat (242), and a plurality of ring-shaped groove (243) is formed concentrically.

  According to this, when the gaseous fuel passes through the ring-shaped groove portion during fuel injection, the temperature of the gaseous fuel decreases due to expansion and cooling, and low-temperature gaseous fuel or condensed water is accumulated in the ring-shaped groove. Therefore, even when a part of the high-temperature combustion gas passes through the downstream valve portion and flows to the upstream valve portion when the valve is closed, the combustion gas passing through the downstream valve portion does not accumulate in the ring-shaped groove. Since it is cooled by gaseous fuel or condensed water, it is possible to more reliably prevent melting damage of the resin seal member.

In the invention according to claim 1, 2, shea seal member (28), after spraying the resin into needle (23) or valve body (24), characterized in that it is formed by cutting.

  According to this, even when the thickness of the seal member is small, the seal member can be easily formed.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a typical sectional view of an internal-combustion engine provided with a fuel injection valve concerning a 1st embodiment of the present invention. It is sectional drawing of the fuel injection valve single-piece | unit of FIG. It is an expanded sectional view of the principal part in the fuel injection valve of FIG. It is sectional drawing of the principal part which shows the 1st modification of the fuel injection valve which concerns on 1st Embodiment. It is sectional drawing of the principal part which shows the 2nd modification of the fuel injection valve which concerns on 1st Embodiment. It is sectional drawing of the principal part which shows the 3rd modification of the fuel injection valve which concerns on 1st Embodiment. It is sectional drawing of the principal part which shows the 4th modification of the fuel injection valve which concerns on 1st Embodiment. It is sectional drawing of the principal part in the fuel injection valve which concerns on 2nd Embodiment of this invention. It is sectional drawing of the fuel injection valve which concerns on 3rd Embodiment of this invention. It is an expanded sectional view of the principal part in the fuel injection valve of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view of an internal combustion engine including a fuel injection valve according to the first embodiment.

  As shown in FIG. 1, in the internal combustion engine, a combustion chamber 13 is formed by a cylinder head 10, a cylinder block 11, and a piston 12. The cylinder head 10 is formed with an intake port 14 that guides the air-fuel mixture to the combustion chamber 13 and an exhaust port 15 that serves as an outlet for the gas burned in the combustion chamber 13. The cylinder head 10 is provided with an intake valve 16 for opening and closing the intake port 14 and an exhaust valve 17 for opening and closing the exhaust port 15.

  A spark plug 18 is disposed in the cylinder head 10 at a position facing the center in the radial direction in the combustion chamber 13. The spark plug 18 generates a discharge spark when a high voltage is applied at a predetermined timing from an ignition circuit (not shown), and ignites the air-fuel mixture in the combustion chamber 13.

  In the cylinder head 10, the fuel injection valve 2 is disposed at a position facing the outer periphery of the combustion chamber 13. The fuel injection valve 2 directly injects gaseous fuel supplied from the fuel supply device 3 into the combustion chamber 13.

  The fuel supply device 3 stores fuel such as hydrogen or CNG (compressed natural gas) in a gas state in a fuel cylinder (not shown), adjusts the gaseous fuel to a predetermined pressure, and supplies the fuel to the fuel injection valve 2. It has become.

  FIG. 2 is a sectional view of the single fuel injection valve of FIG. As shown in FIG. 2, the fuel injection valve 2 forms a magnetic field when energized in a space formed by a cylindrical case 20 made of a magnetic metal (for example, stainless steel) and a resin cover 21 that is rich in corrosion resistance. A cylindrical coil 22 is accommodated.

  The case 20, the coil 22, and the needle 23, the valve body 24, and the core 25, which will be described later, are arranged coaxially. Hereinafter, the common axis is simply referred to as an axis, and the direction of the common axis is defined as the common axis. The direction is simply called the axial direction, and the direction perpendicular to the common axis is simply called the radial direction.

  In the case 20, a bottomed cylindrical needle 23 made of a magnetic metal (for example, stainless steel) rich in corrosion resistance is disposed on the inner peripheral side of the coil 22. The needle 23 is slidably held in the case 20 and can reciprocate in the axial direction.

  The needle 23 is formed with a needle vertical hole 230 as a fuel passage extending in the axial direction and a needle horizontal hole 231 as a fuel passage extending in the radial direction and communicating with the needle vertical hole 230.

  A cylindrical valve body 24 made of metal (for example, stainless steel) rich in corrosion resistance is disposed on one end side of the needle 23 in the axial direction. The valve body 24 is fixed to the case 20. The valve body 24 is formed with a valve body vertical hole 240 as a fuel passage penetrating in the axial direction. The valve body vertical hole 240 is located in the center in the radial direction.

  On the other end side in the axial direction of the needle 23, a cylindrical core 25 made of a magnetic metal (for example, stainless steel) rich in corrosion resistance is disposed. One end side of the core 25 is inserted into the inner peripheral side of the coil 22, and the other end side protrudes from the cover 21. The core 25 is sandwiched between the coil 22 and the cover 21. Further, a core vertical hole 250 is formed in the core 25 as a fuel passage penetrating in the axial direction.

  A spring 26 is disposed between the needle 23 and the core 25 to urge the needle 23 toward the valve body 24 (that is, toward the valve closing direction).

  A flow space 27 as a fuel passage is formed between the outer peripheral surface of the needle 23 on the valve body 24 side and the inner peripheral surface of the case 20. This circulation space 27 is always in communication with the needle lateral hole 231 and in communication with the valve body vertical hole 240 when the valve is opened.

  The gaseous fuel supplied from the fuel supply device 3 (see FIG. 1) flows from the core vertical hole 250 and then flows in the order of the needle vertical hole 230, the needle horizontal hole 231, the flow space 27, and the valve body vertical hole 240 in order. 13 (see FIG. 1).

  FIG. 3 is an enlarged cross-sectional view of a main part of the fuel injection valve of FIG. More specifically, FIG. 3 (a) is a cross-sectional view showing a valve open state, FIG. 3 (b) is a cross-sectional view showing a state in which an upstream valve portion is closed, and FIG. 3 (c) is a view showing a downstream valve portion. It is sectional drawing which shows the state which valve-closed.

  As shown in FIGS. 2 and 3, the needle 23 and the valve body 24 face each other on one end side in the axial direction of the needle 23 (that is, the bottom side of the needle 23). Incidentally, in the fuel injection valve of the present embodiment, when the fuel passes between the opposed surfaces of the needle 23 and the valve body 24, the fuel flows from the radially outer side to the inner side.

  A seal member 28 having a ring shape and a rectangular cross section is provided on the surface of the needle 23 that faces the valve body 24. The seal member 28 is press-fitted into the needle 23 and integrated.

  The seal member 28 is made of a resin having high heat resistance. Specifically, fluororubber, acrylonitrile butadiene rubber (NBR), fluororesin, tetrafluoroethylene (PTFE), polybutylene terephthalate (PBT), or the like is used. it can.

  A downstream needle seat portion 232 is formed on the surface of the needle 23 facing the valve body 24 on the inner peripheral side of the seal member 28 (that is, on the fuel flow downstream side of the seal member 28). The downstream needle seat portion 232 is a plane perpendicular to the axis.

  The mounting surface 235 of the needle 23 on which the seal member 28 is mounted is located on the side opposite to the valve body from the downstream needle seat portion 232. In other words, the downstream needle seat portion 232 and the mounting surface 235 are displaced in the axial direction. The end surface of the seal member 28 on the valve body 24 side protrudes further toward the valve body 24 than the downstream needle seat portion 232.

  A surface of the valve body 24 facing the seal member 28 and the downstream needle seat portion 232 is a plane perpendicular to the axis.

  The surface of the valve body 24 facing the seal member 28 is an upstream body seat portion 241 that opens and closes the fuel passage by contact with and separation from the seal member 28, and the seal member 28 and the upstream body seat portion 241 are formed according to the present invention. An upstream valve portion is configured.

  Further, the surface of the valve body 24 that faces the downstream needle seat portion 232 becomes a downstream body seat portion 242 that opens and closes the fuel passage by contact with and separation from the downstream needle seat portion 232. The side body seat portion 242 constitutes the downstream valve portion of the present invention. The upstream valve portion and the downstream valve portion are disposed concentrically.

  As shown in FIG. 3C, the seal member 28 is deformed when the valve is closed between the inner peripheral surface of the seal member 28 and the downstream needle seat 232 (that is, the inner peripheral side of the seal member 28). An inner circumferential side relief space 233 that allows the above is formed. Further, an outer peripheral side relief space 234 that allows deformation of the seal member 28 when the valve is closed is formed on the outer peripheral side of the seal member 28.

  Next, the operation of the fuel injection valve configured as described above will be described. First, when the coil 22 is energized, the needle 23 is attracted toward the core 25 by electromagnetic force. Thereby, as shown in FIG. 3A, the seal member 28 and the upstream body seat portion 241 are separated from each other so that the upstream valve portion is opened, and the downstream needle seat portion 232 and the downstream body seat portion are opened. As a result, the downstream valve portion is opened, and gaseous fuel is injected from the valve body vertical hole 240 into the combustion chamber 13 (see FIG. 1).

  When energization of the coil 22 is stopped, the needle 23 is urged toward the valve body 24 by the spring 26 (that is, in the valve closing direction). Here, since the end surface on the valve body 24 side of the seal member 28 protrudes toward the valve body 24 rather than the downstream needle seat portion 232, the upstream valve portion closes before the downstream valve portion. That is, as shown in FIG. 3B, the seal member 28 and the upstream body seat portion 241 come into contact with each other, the upstream valve portion is closed, and the injection of gaseous fuel is stopped. And since the sealing member 28 is resin, the favorable sealing performance at the time of valve closing is ensured.

  When the seal member 28 and the upstream body seat portion 241 abut, the needle 23 is biased toward the valve body 24 by the pressure of the gaseous fuel and the spring 26, as shown in FIG. The seal member 28 is compressed in the axial direction, the downstream needle seat portion 232 and the downstream body seat portion 242 come into contact with each other, and the downstream valve portion is also closed.

  Here, in the internal combustion engine of the type in which gaseous fuel is directly injected into the combustion chamber 13, the fuel is combusted by igniting by the spark plug 18 after the injection is completed, so that the combustion gas tends to flow into the fuel injection valve. Sometimes, the downstream valve portion is closed. Therefore, the closing of the downstream valve portion prevents high-temperature combustion gas from flowing to the upstream valve portion and prevents the sealing member 28 from being melted.

  Incidentally, in the case of an internal combustion engine that is ignited and burned during fuel injection, the supply pressure of the gaseous fuel is set higher than the combustion gas pressure, so that the combustion gas cannot reach the seal member 28. Further, some leakage is allowed even if the downstream valve portion is closed. This is because the combustion gas expands when it tries to leak and the temperature drops, and when the combustion gas that has been hot reaches the seal member 28, the temperature is very low, so the seal member 28 is melted. I will not let you.

  Further, the seal member 28 is in a period from when only the upstream valve portion is closed (the state shown in FIG. 3B) to when the downstream valve portion is also closed (the state shown in FIG. 3C). Is expanded in the radial direction while being compressed in the axial direction, but since the inner peripheral side escape space 233 and the outer peripheral side escape space 234 are formed, expansion of the seal member 28 in the radial direction is not hindered. Therefore, the seal member 28 can be easily deformed, and the downstream valve portion can be reliably closed.

  Furthermore, as described above, the seal member 28 expands in the radial direction while being compressed in the axial direction, so that the seal member 28 functions as a damper, and the downstream needle seat portion 232 and the downstream body seat portion 242 Since the collision speed is reduced, the wear of those seat portions can be prevented or suppressed.

  Furthermore, when the downstream valve portion is closed, the downstream valve portion functions as a stopper and can regulate the deformation amount of the seal member 28, thereby preventing or suppressing the deterioration of the seal member 28. Can do.

  In the above embodiment, the sealing member 28 having a rectangular cross-sectional shape is used. However, as in the first modification shown in FIG. 4, the sealing member 28 having a triangular cross-sectional shape may be used. As shown in the second modification example, a sealing member 28 having a circular or oval cross-sectional shape may be used. In this case, since the seal member 28 can be deformed with a small force after the seal member 28 and the upstream body sheet portion 241 come into contact with each other, the urging force of the spring 26 can be set small.

  In the above-described embodiment, the downstream needle seat portion 232 and the downstream body seat portion 242 are both flat. However, as in the third modification shown in FIG. 6, the downstream needle seat portion 232 and the downstream body Any one of the seat portions 242 may be a ring-shaped seat portion having a triangular cross-sectional shape, or the downstream needle seat portion 232 and the downstream body seat as in the fourth modification shown in FIG. Any one of the portions 242 may be a ring-shaped sheet portion having a substantially semicircular cross-sectional shape. In this case, since the downstream valve portion has a higher surface pressure when the valve is closed, the sealing performance is improved.

(Second Embodiment)
A second embodiment of the present invention will be described. FIG. 8 is a cross-sectional view of a main part of the fuel injection valve according to the second embodiment. Only the parts different from the first embodiment will be described below.

  As shown in FIG. 8, a plurality of ring-shaped grooves 243 are concentrically formed in the downstream body sheet portion 242.

  According to this, when the gaseous fuel passes through the portion of the groove 243 at the time of fuel injection, the temperature of the gaseous fuel decreases due to expansion and cooling, and low-temperature gaseous fuel or condensed water is accumulated in the groove 243. Therefore, even when a part of the high-temperature combustion gas passes through the downstream valve portion and flows to the upstream valve portion when the valve is closed, the combustion gas passing through the downstream valve portion is stored in the groove 243. Since it is cooled by dew condensation water, it is possible to more reliably prevent the sealing member 28 from being melted.

(Third embodiment)
A third embodiment of the present invention will be described. FIG. 9 is a cross-sectional view of the fuel injection valve according to the third embodiment, and FIG. 10 is an enlarged cross-sectional view of the main part of the fuel injection valve of FIG. Only the parts different from the first embodiment will be described below.

  As shown in FIGS. 9 and 10, the needle 23 has the needle lateral hole 231 eliminated and the needle vertical hole 230 penetrates in the axial direction. The needle vertical hole 230 is located at the center in the radial direction. A plurality of valve body vertical holes 240 are formed in the valve body 24 at positions shifted from the radial center. Incidentally, in the fuel injection valve of the present embodiment, when the fuel passes between the opposing surfaces of the needle 23 and the valve body 24, the fuel flows from the radially inner side to the outer side.

  A seal member 28 is provided on the surface of the needle 23 facing the valve body 24 so as to surround the open end of the needle vertical hole 230. The inner peripheral surface of the seal member 28 is continuous with the needle vertical hole 230, and the needle vertical hole 230 also serves as an inner peripheral side escape space. Further, the downstream needle seat portion 232 is formed on the outer peripheral side of the seal member 28 (that is, the fuel flow downstream side of the seal member 28).

  On the other hand, in the valve body 24, an upstream body seat portion 241 that contacts and separates from the seal member 28 is formed on the inner peripheral side of the downstream body seat portion 242 that contacts and separates from the downstream needle seat portion 232.

  Further, in order to prevent combustion gas from flowing into the coil 22 side through the clearance between the needle 23 and the case 20, the outer peripheral surface of the needle 23 on the valve body 24 side and the inner peripheral surface of the case 20 Between the two, a metal diaphragm 29 is provided. The diaphragm 29 is joined to the needle 23 and the valve body 24 by welding. The spring 26 can be omitted by providing the diaphragm 29 with a spring function.

  Furthermore, the flow space 27 is also abolished together with the needle lateral hole 231. Therefore, after flowing in from the core vertical hole 250, the gaseous fuel flows in the order of the needle vertical hole 230 and the valve body vertical hole 240, and the combustion chamber 13 (see FIG. 1). Is to be injected.

  According to this embodiment, the same effect as the first embodiment can be obtained. That is, since the sealing member 28 is made of resin, a good sealing property when the valve is closed is ensured. Further, the valve closing of the downstream valve portion prevents the high-temperature combustion gas from flowing to the upstream valve portion, thereby preventing the sealing member 28 from being melted. Furthermore, since the expansion of the seal member 28 in the radial direction is not hindered, the seal member 28 can be easily deformed, and the downstream valve portion can be reliably closed. Furthermore, the seal member 28 can exhibit the function of a damper, thereby preventing or suppressing wear of the downstream needle seat portion 232 and the downstream body seat portion 242. Furthermore, since the downstream valve portion functions as a stopper and the deformation amount of the seal member 28 can be defined, the deterioration of the seal member 28 can be prevented or suppressed.

(Other embodiments)
In each of the above embodiments, the seal member 28 is press-fitted into the needle 23, but the seal member 28 may be bonded to the needle 23 with an adhesive. In this case, the seal member 28 and the needle 23 can be easily integrated.

  Moreover, in each said embodiment, although the sealing member 28 was press-fit in the needle 23, you may form the sealing member 28 by insert molding. In this case, the seal member 28 can be easily formed, and the seal member 28 and the needle 23 can be firmly coupled.

  Furthermore, in each said embodiment, although the sealing member 28 was press-fit in the needle 23, after spraying resin to the needle 23, you may cut and form the sealing member 28. FIG. In this case, even when the thickness of the seal member 28 is small, the seal member 28 can be easily formed.

  Furthermore, in each of the above embodiments, the seal member 28 is attached to the needle 23, but the seal member 28 may be attached to the valve body 24. In this case, the surface of the needle 23 facing the seal member 28 becomes an upstream needle seat portion that opens and closes the fuel passage by contact with and separation from the seal member 28, and the seal member 28 and the upstream needle seat portion are upstream of the present invention. Configure the valve.

  Moreover, each said embodiment can be arbitrarily combined in the range which can be implemented.

13 Combustion chamber 23 Needle 24 Valve body 27 Distribution space (fuel passage)
28 Seal member 230 Vertical needle hole (fuel passage)
231 Needle lateral hole (fuel passage)
232 Downstream needle seat 240 Valve body vertical hole (fuel passage)
241 Upstream body seat 242 Downstream body seat 250 Core vertical hole (fuel passage)

Claims (9)

A fuel passage (27, 230, 231, 240, 250) through which gaseous fuel flows is provided, and a reciprocating metal needle (23) contacts and separates from the metal valve body (24) to open and close the fuel passage. A fuel injection valve for directly injecting gaseous fuel into the combustion chamber (13) of the internal combustion engine when the valve is opened,
The needle is provided with a resin seal member (28), and a downstream needle seat portion (232) is formed on the fuel flow downstream side of the seal member.
The valve body includes an upstream body seat portion (241) that opens and closes the fuel passage by contact and separation with the seal member, and a downstream body that opens and closes the fuel passage by contact and separation with the downstream needle seat portion. A sheet portion (242) is formed,
When shifting from the open state to the closed state, the downstream needle seat and the downstream body seat are in contact with each other after the sealing member and the upstream body seat are in contact with each other. ,
The fuel injection valve , wherein the seal member is formed by cutting resin after spraying the needle or the valve body . A fuel passage (27, 230, 231, 240, 250) through which gaseous fuel flows is provided, and a reciprocating metal needle (23) contacts and separates from the metal valve body (24) to open and close the fuel passage. A fuel injection valve for directly injecting gaseous fuel into the combustion chamber (13) of the internal combustion engine when the valve is opened,
The valve body is provided with a resin seal member (28), and a downstream body seat portion (242) is formed on the fuel flow downstream side of the seal member,
The needle includes an upstream needle seat portion that opens and closes the fuel passage by contact and separation with the seal member, and a downstream needle seat portion that opens and closes the fuel passage by contact and separation with the downstream body seat portion (232). ) Is formed,
When shifting from the open state to the closed state, the downstream needle seat portion and the downstream body seat portion are in contact with each other after the sealing member and the upstream needle seat portion are in contact with each other. ,
The fuel injection valve , wherein the seal member is formed by cutting resin after spraying the needle or the valve body . The needle and the valve body (24) face each other at one axial end side of the needle (23),
The seal member (28) and the seat portions are located on the opposing surfaces of the needle and the valve body,
An upstream valve portion constituted by the seal member and the upstream body seat portion (241), and a downstream side constituted by the downstream needle seat portion (232) and the downstream body seat portion (242). The fuel injection valve according to claim 1, wherein the valve portions are arranged concentrically. The needle and the valve body (24) face each other at one axial end side of the needle (23),
The seal member (28) and the seat portions are located on the opposing surfaces of the needle and the valve body,
An upstream valve portion constituted by the seal member and the upstream needle seat portion, and a downstream valve portion constituted by the downstream needle seat portion (232) and the downstream body seat portion (242) are: The fuel injection valve according to claim 2, wherein the fuel injection valves are arranged concentrically.   Relief spaces (233, 234) that allow deformation of the seal member when the valve is closed are formed on the inner peripheral side and the outer peripheral side of the seal member (28), respectively. The fuel injection valve as described.   The fuel injection valve according to any one of claims 3 to 5, wherein a plurality of ring-shaped grooves (243) are concentrically formed in the downstream body seat portion (242). A fuel passage (27, 230, 231, 240, 250) through which gaseous fuel flows is provided, and a reciprocating metal needle (23) contacts and separates from the metal valve body (24) to open and close the fuel passage. A fuel injection valve for directly injecting gaseous fuel into the combustion chamber (13) of the internal combustion engine when the valve is opened,
  The needle is provided with a resin seal member (28), and a downstream needle seat portion (232) is formed on the fuel flow downstream side of the seal member.
The valve body includes an upstream body seat portion (241) that opens and closes the fuel passage by contact and separation with the seal member, and a downstream body that opens and closes the fuel passage by contact and separation with the downstream needle seat portion. A sheet portion (242) is formed,
When shifting from the open state to the closed state, the downstream needle seat and the downstream body seat are in contact with each other after the sealing member and the upstream body seat are in contact with each other. ,
The needle and the valve body face each other at one axial end side of the needle,
The seal member and each seat portion are located on opposing surfaces of the needle and the valve body,
The upstream valve portion constituted by the seal member and the upstream body seat portion, and the downstream valve portion constituted by the downstream needle seat portion and the downstream body seat portion are arranged concentrically. And
A fuel injection valve characterized in that a plurality of ring-shaped grooves (243) are concentrically formed in the downstream body seat portion. A fuel passage (27, 230, 231, 240, 250) through which gaseous fuel flows is provided, and a reciprocating metal needle (23) contacts and separates from the metal valve body (24) to open and close the fuel passage. A fuel injection valve for directly injecting gaseous fuel into the combustion chamber (13) of the internal combustion engine when the valve is opened,
The valve body is provided with a resin seal member (28), and a downstream body seat portion (242) is formed on the fuel flow downstream side of the seal member,
The needle includes an upstream needle seat portion that opens and closes the fuel passage by contact and separation with the seal member, and a downstream needle seat portion that opens and closes the fuel passage by contact and separation with the downstream body seat portion (232). ) Is formed,
When shifting from the open state to the closed state, the downstream needle seat portion and the downstream body seat portion are in contact with each other after the sealing member and the upstream needle seat portion are in contact with each other. ,
The needle and the valve body face each other at one axial end side of the needle,
The seal member and each seat portion are located on opposing surfaces of the needle and the valve body,
The upstream valve portion constituted by the seal member and the upstream needle seat portion, and the downstream valve portion constituted by the downstream needle seat portion and the downstream body seat portion are arranged concentrically. And
A fuel injection valve characterized in that a plurality of ring-shaped grooves (243) are concentrically formed in the downstream body seat portion. The escape space (233, 234) that allows deformation of the seal member when the valve is closed is formed on an inner peripheral side and an outer peripheral side of the seal member (28). The fuel injection valve as described.

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