JP5126079B2 - Fuel injection valve - Google Patents

Description

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

  2. Description of the Related Art Conventionally, a fuel injection valve that controls a biasing force in a valve closing direction that acts on a valve member by adjusting a fuel pressure in a pressure control chamber with a pressure control valve and controls an opening / closing operation of the valve member is known. (See Patent Document 1). In the fuel injection valve described in Patent Document 1, by opening the pressure control valve, the fuel in the pressure control chamber is discharged to the low pressure side through the pressure control chamber outlet-side orifice. As a result, the fuel pressure in the pressure control chamber is lowered, the urging force acting on the valve member in the valve closing direction is lowered, and the valve member is opened.

JP 2006-194237 A

  In the conventional fuel injection valve described above, the fuel passage of the pressure control chamber outlet side orifice communicates with a valve chamber formed above the pressure control valve. As a result, the valve chamber is filled with fuel, and the upper periphery of the pressure control valve is filled with fuel. With such a configuration, the fuel becomes a resistance against the vibration of the pressure control valve, and the vibration of the pressure control valve can be suppressed.

  However, when the pressure control valve is opened, the fuel flows through the fuel passage to the periphery of the pressure control valve, and the kinetic energy of the fuel due to the flow acts on the upper part (blade part) of the pressure control valve. In addition, hydraulic pulsation acts on the upper part (blade part) of the pressure control valve by the fuel flowing through the fuel passage. Due to these actions, the behavior of the pressure control valve becomes unstable, and there is a problem that a minute unstable behavior is brought about in the opening / closing operation of the valve member.

  Therefore, the present invention has been made in view of the above-described problems, and an object thereof is to provide a fuel injection valve that can stabilize the behavior of a pressure control valve.

  The present invention employs the following technical means in order to achieve the aforementioned object.

In the invention according to claim 1, a cylindrical housing in which a nozzle hole for injecting fuel is formed;
A valve member that is provided in the housing, opens and closes the injection hole by reciprocating in the axial direction of the housing, and intermittently injects fuel from the injection hole;
A supply section for supplying fuel with increased pressure into the housing;
A high-pressure fuel passage formed inside the housing and guiding the fuel supplied from the supply section to the nozzle hole;
A pressure control chamber formed inside the housing and supplied with fuel flowing through the high pressure fuel passage;
A first communication path connected to the pressure control chamber;
A storage chamber disposed downstream of the first communication path;
A discharge passage for discharging the fuel flowing into the storage chamber out of the housing;
Drive means for controlling discharge of fuel in the pressure control chamber to the storage chamber and stop of discharge by opening and closing the first communication path,
The pressure in the pressure control chamber acts on the end of the valve member located on the opposite side of the nozzle hole in the direction of closing the valve member,
The driving means is
A fixed portion fixed to the inner peripheral surface portion of the housing;
A pressure control valve that is axially displaced with respect to the fixed portion and opens and closes the first communication path;
An elastic member that presses the pressure control valve in a direction to close the first communication path;
A coil that generates a magnetic force that attracts the pressure control valve to open the first communication path when energized,
A through hole is formed in the fixed portion so as to penetrate in the axial direction,
In the through hole, the pressure control valve is arranged to slide in the axial direction,
The end of the pressure control valve located on the side opposite to the nozzle hole side is provided with a vane portion that projects radially outward and regulates the displacement of the pressure control valve to the side opposite to the nozzle hole side with respect to the fixed portion. ,
The outer peripheral surface portion of the fixed portion and the inner peripheral surface portion of the housing are in contact with each other,
The inner peripheral surface portion of the fixed portion and the outer peripheral surface portion penetrating the through hole of the pressure control valve are in contact with each other,
In the fixed portion, a supply passage that extends in the radial direction from the through hole and reaches the discharge passage without reaching the surface portion of the fixed portion that is located on the side opposite to the injection hole side is formed.
A plurality of slit grooves (60) are formed as second communication passages at intervals in the circumferential direction on the side surface of the fixed portion, and an arrangement space (53) and a discharge passage in which the blade portions are arranged by the second communication passages. (39) is in communication,
The opening on the downstream side of the passage communicating with the placement space by the second communication passage does not face the blade portion so as to reduce the external force acting on the blade portion caused by the flow of fuel into the placement space. Formed in position,
When the pressure control valve is open, fuel discharged from the first communication passage flows down the supply passage, Itaru Rutotomoni in the discharge passage, characterized in that leads to arrangement space through the second communication passage Fuel injection valve.

According to the first aspect of the present invention, the first communication passage is provided on the nozzle hole side of the fixed part, and the blade part is disposed on the counter nozzle hole side of the fixed part. The outer peripheral surface portion of the fixed portion is in contact with the inner peripheral surface portion of the housing, and the inner peripheral surface portion is in contact with the outer peripheral surface portion of the pressure control valve. The fixed portion is formed with a second communication passage that communicates the supply passage and the arrangement space in which the supply passage and the blade portion are disposed.

  Further, since the arrangement space can be always filled with fuel, the fuel around the blade portion can be always filled with fuel without being deficient. As a result, the fuel becomes a resistance against the vibration of the pressure control valve, and the vibration of the pressure control valve can be suppressed.

Since the opening of the second communication path is formed at a position that does not face the blade portion, when fuel flows into the arrangement space, it is possible to reduce as much as possible that an external force caused by the flowing in acts on the blade portion. . Therefore, even if the amount of inflow becomes large, the external force acting on the blades is small, so it is possible to reliably prevent problems caused by the inflow of fuel and to always fill the arrangement space with fuel. .

It is sectional drawing which shows the whole structure of the fuel injection valve 10 of a 1st reference example . 2 is an enlarged cross-sectional view of a main part of the fuel injection valve 10. FIG. 2 is a cross-sectional view showing a valve body 41. FIG. 3 is a plan view showing a valve body 41. FIG. It is an example of sectional drawing which expanded the principal part of fuel injection valve 10A of the 2nd reference example . It is another example of sectional drawing which expanded the principal part of fuel injection valve 10A of the 2nd reference example . It is sectional drawing to which the principal part of the fuel injection valve 10B of 1st Embodiment was expanded. It is sectional drawing which shows the valve body 41 of 1st Embodiment . It is a top view which shows the valve body 41 of 1st Embodiment . It is sectional drawing which shows valve body 41C of 2nd Embodiment . It is sectional drawing to which the principal part of fuel injection valve 10D of the 3rd reference example was expanded.

Hereinafter, reference examples and embodiments for carrying out the present invention will be described with reference to the drawings. Portions corresponding to items described in the reference example that precedes the embodiment are denoted by the same reference numerals, and redundant descriptions may be omitted. In addition, when a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those of the embodiment described in advance. In addition to the combination of parts specifically described in each embodiment, the embodiments may be partially combined as long as the combination does not hinder the combination.

(First Reference Example )
A first reference example of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing an overall configuration of a fuel injection valve 10 of a first reference example . FIG. 2 is an enlarged cross-sectional view of a main part of the fuel injection valve 10. The fuel injection valve 10 is used, for example, in a common rail fuel injection device for a diesel engine. The fuel injection valve 10 is mounted on an engine head (not shown) of the engine, and is configured to directly inject high-pressure fuel supplied from a common rail (not shown) that accumulates high-pressure fuel into each cylinder of the engine. ing. The fuel injection valve 10 includes a nozzle unit 11, a nozzle holder unit 12, and a pressure control unit 13.

  The nozzle part 11 is coupled to the nozzle holder part 12 by a retaining nut 14. The nozzle unit 11 includes a nozzle body 15 and a needle 16. The nozzle body 15 is formed with a needle accommodation hole 17 that is a rod-shaped recess extending in the axial direction Z and in which the needle 16 is accommodated. A nozzle hole 18 that connects the inner wall of the needle housing hole 17 and the outer wall of the nozzle body 15 is formed at the tip of the needle housing hole 17. A valve seat 19 on which the needle 16 is seated is formed on the upstream side of the nozzle hole 18 of the needle housing hole 17.

  Hereinafter, as a direction indicating the fuel injection valve 10, a direction in which the needle accommodation hole 17 extends is referred to as an axial direction Z (vertical direction in FIG. 1), and one of the axial directions Z is a valve opening direction Z1 or an upper Z1 (upper direction in FIG. 1). ) And the other of the axial directions Z may be referred to as a valve closing direction Z2 or a downward direction Z2 (downward in FIG. 1).

  In the nozzle body 15, a nozzle body passage 20 connected to the side wall of the needle accommodation hole 17 is formed. The nozzle body passage 20 functions as a high-pressure fuel passage and supplies high-pressure fuel to the needle accommodation hole 17.

  The needle 16 is formed in a rod shape extending in the axial direction Z and is accommodated in the needle accommodation hole 17. When the needle 16 is accommodated in the needle accommodation hole 17, a fuel reservoir chamber 21 surrounded by the outer wall of the needle 16 and the inner wall of the needle accommodation hole 17 is formed. The fuel reservoir chamber 21 communicates with the nozzle body passage 20 and the nozzle hole 18. The needle 16 has a pressure receiving portion 22. When fuel is supplied to the fuel reservoir chamber 21, the fuel pressure acts on the pressure receiving portion 22. Then, a force that pushes the needle 16 in the valve opening direction Z1 acts on the needle 16.

  The needle 16 is a valve member. When the needle 16 is seated on the valve seat 19, the communication between the fuel reservoir chamber 21 and the injection hole 18 is blocked. For this reason, even if the high pressure fuel is supplied to the fuel reservoir chamber 21, the fuel is not injected from the nozzle hole 18. When the needle 16 moves away from the valve seat 19, the fuel reservoir chamber 21 and the injection hole 18 communicate with each other, so that fuel is injected from the injection hole 18.

  The nozzle holder unit 12 supports the nozzle unit 11 at one end, and supports the pressure control unit 13 at the other end. The nozzle holder unit 12 includes a lower body 23, a command piston 24, a coil spring 25, and an orifice plate 26.

  The lower body 23 is formed in a rod shape extending in the axial direction Z, and supports the nozzle body 15 at the end of the lower side Z2. In other words, the lower body 23 functions as a cylindrical housing. The lower body 23 has a high-pressure opening 27 to which a fuel pipe (not shown) extending from a common rail (not shown) is connected. Therefore, the high-pressure opening 27 functions as a supply unit for supplying high-pressure fuel into the lower body 23. A filter member 28 is attached to the high-pressure opening 27 to prevent foreign matter from entering the fuel injection valve 10. The lower body 23 is formed with a lower body passage 29 connected to the nozzle body passage 20. The lower body passage 29 functions as a high pressure fuel passage and supplies the high pressure fuel flowing into the high pressure opening 27 to the nozzle body passage 20.

  A concave portion 33 that is recessed toward the lower Z2 is formed at the end of the upper body Z1 of the lower body 23. The lower body 23 is formed with a branch passage 34 branched from the lower body passage 29. The branch passage 34 opens at the bottom of the recess 33. The lower body 23 is formed with a piston accommodating hole 35 extending in the axial direction Z. The end of the piston accommodation hole 35 located on the recess 33 side opens at the bottom of the recess 33. Further, the end of the piston accommodation hole 35 located on the nozzle part 11 side is open to the end face on the nozzle part 11 side. The piston accommodation hole 35 communicates with the needle accommodation hole 17. A command piston 24 formed in a rod shape extending in the axial direction Z is accommodated in the piston accommodation hole 35 so as to be reciprocally movable.

  A coil spring 25 is provided at the end of the piston accommodation hole 35 located on the nozzle portion 11 side. The upper end of the coil spring 25 is supported by the inner wall of the piston accommodation hole 35, and the lower end is supported by the upper end surface of the needle 16. The coil spring 25 biases the needle 16 in the valve closing direction Z2.

  The lower body 23 is formed with a leak passage 55 that communicates a gap formed between the piston accommodation hole 35 and the command piston 24 and the recess 33. Further, the lower body 23 is formed with a low pressure passage 30 for discharging the fuel leaked inside the pressure control unit 13 to the low pressure side. The low pressure passage 30 communicates a recess 33 and a pipe (not shown) connected to the low pressure opening 32, and the fuel that has flowed down is discharged to a low pressure side such as a fuel tank.

  The orifice plate 26 is formed in a substantially disk shape, and is provided at the bottom of the recess 33 so as to cover the piston accommodation hole 35. A pressure control chamber 36 communicating with the piston accommodation hole 35 is formed on the end face of the orifice plate 26 located on the bottom side of the recess 33. The orifice plate 26 is formed with an out-orifice 37 and an in-orifice 38. The out-orifice 37 is a first communication passage, and communicates the end surface of the orifice plate 26 located on the opposite side (upper Z1 side in FIG. 1) with the pressure control chamber 36. The in-orifice 38 communicates the branch passage 34 and the pressure control chamber 36. The passage sectional area of the out orifice 37 is larger than the passage sectional area of the in orifice 38.

  High pressure fuel is supplied to the pressure control chamber 36 through the branch passage 34. The pressure of the high-pressure fuel supplied to the pressure control chamber 36 acts on the upper end surface of the command piston 24. As a result, a force is applied to the command piston 24 to push the needle 16 downward Z2, that is, the needle 16 in the valve closing direction Z2.

  Since the outer diameter of the orifice plate 26 is smaller than the inner diameter of the recess 33, a fuel passage 39 that functions as a discharge passage is formed between the outer wall of the orifice plate 26 and the inner wall of the recess 33. The fuel passage 39 communicates with the leak passage 55.

Next, the pressure control unit 13 will be described. The pressure control unit 13 functions as a driving unit that controls the discharge of the high-pressure fuel in the pressure control chamber 36 to the fuel passage 39 and the stop of the discharge by opening and closing the out orifice 37. The pressure control unit 13 is assembled to the upper portion Z <b> 1 of the nozzle holder unit 12, and is bonded and fixed to the upper portion of the lower body 23 by the upper body 40. The pressure control unit 13 includes a valve body 41, an armature 42 and a solenoid 43. The valve body 41 is a fixed portion and is fixed to the inner peripheral surface portion of the lower body 23. Therefore, the outer peripheral surface portion of the valve body 41 is in contact with the inner peripheral surface portion of the lower body 23. The portion that is in contact in this way is a portion where fuel does not flow between the outer peripheral surface portion of the valve body 41 and the inner peripheral surface portion of the lower body 23. In this reference example , the contacting portion extends over the entire circumferential direction of the valve body 41, and fuel does not flow between the outer peripheral surface portion of the valve body 41 and the inner peripheral surface portion of the lower body 23.

More specifically, in this reference example , a male screw is formed on the outer peripheral surface portion of the valve body 41, and a female screw is formed on the inner peripheral surface portion of the lower body 23. 23. As a result, the valve body 41 and the lower body 23 are in close contact with each other.

  The valve body 41 is formed in a substantially cylindrical shape, and is provided on the out orifice 37 side of the orifice plate 26. The lower surface portion of the valve body 41 and the upper surface portion of the orifice plate 26 are in close contact with each other. When the valve body 41 is fixed to the lower body 23, the valve body 41 is screwed downward Z2 so that the lower surface portion of the valve body 41 and the upper surface portion of the orifice plate 26 are brought into close contact with each other. A storage chamber 44 is formed on the lower surface of the valve body 41. A vertical hole 45 extending in the axial direction Z is formed in the upper portion Z <b> 1 of the storage chamber 44. The vertical hole 45 is formed so as to extend in the axial direction Z and penetrate the valve body 41.

The armature 42 is a pressure control valve and is displaced with respect to the valve body 41 to open and close the out orifice 37. The armature 42 includes a substantially disk-shaped disk part 46 and a columnar part 47. The disk part 46 is a blade part and is provided at the end of the armature 42 located on the valve opening direction Z1 side. Accordingly, the disk portion 46 is disposed so as to face the end surface of the valve body 41 on the side opposite to the orifice plate 26. The disk part 46 protrudes outward in the radial direction, and restricts the displacement of the armature 42 in the valve opening direction Z <b > 1 with respect to the valve body 41. The upper surface of the disk portion 46 is a flat surface and is a suction surface that is sucked by the lower surface of the solenoid 43. The cylindrical portion 47 is supported in the vertical hole 45 so as to be able to reciprocate. The cylindrical portion 47 is provided so as to be able to reciprocate along the axial direction Z while sliding on the inner peripheral surface portion of the vertical hole 45. Sliding is to be displaced while contacting. As described above, the vertical hole 45 is a through hole, and is arranged so that the cylindrical portion 47 of the armature 42 penetrates, and the outer peripheral surface portion that penetrates the inner peripheral surface portion of the valve body 41 and the vertical hole 45 of the cylindrical portion 47. Is in a slidable state.

  A valve body chamber 48 including a cylindrical portion and a conical portion is provided at the center of the lower end surface of the columnar portion 47, and a ball valve 49 is accommodated in the valve body chamber 48. The ball valve 49 has a spherical upper surface, but the lower surface has a sealing flat shape that blocks the out-orifice 37 on the upper surface of the orifice plate 26. The ball valve 49 opens and closes the out orifice 37 as the armature 42 reciprocates.

  When the out orifice 37 is opened by the ball valve 49, the high-pressure fuel that has flowed into the pressure control chamber 36 is discharged to the valve body chamber 48 on the low pressure side, and further discharged from the valve body chamber 48 to the storage chamber 44. The fuel pressure in the pressure control chamber 36 can be reduced.

  The solenoid 43 is assembled to the upper part of the lower body 23, and is joined and fixed to the upper part of the lower body 23 by the upper body 40. The solenoid 43 includes a stator 50, a coil 51, and a coil spring 52. The stator 50 is formed in a substantially cylindrical shape, and is provided on the side opposite to the orifice plate 26 with respect to the valve body 41.

  The coil spring 52 is an elastic member that presses the disk portion 46 of the armature 42 in a direction to close the out orifice 37. The coil 51 generates a magnetic force that attracts the armature 42 so as to open the out orifice 37 when energized.

A valve chamber 53 is formed between the stator 50 and the valve body 41 to accommodate the disc portion 46 of the armature 42 and to allow the disc portion 46 to reciprocate. Therefore, the valve chamber 53 is an arrangement space in which the disk portion 46 is arranged. The valve chamber 53 is preliminarily filled with a fluid having viscosity when assembled, and is filled with oil in this reference example .

  Next, the configuration of the valve body 41 will be further described. FIG. 3 is a cross-sectional view showing the valve body 41. FIG. 4 is a plan view showing the valve body 41. As shown in FIGS. 3 and 4, the valve body 41 is formed with a supply passage 54 through which fuel flows, in addition to the vertical holes 45. The supply passage 54 extends in the radial direction from the vertical hole 45 and is formed to reach the low pressure passage 30 without reaching the surface portion of the valve body 41 located on the lower Z2 side. In other words, when the armature 42 is opened, the supply passage 54 is connected to the low pressure passage 30 without the fuel discharged from the out orifice 37 reaching the surface portion of the valve body 41 located in the valve opening direction Z1. The out orifice 37 is communicated. Therefore, the passage from the lower surface portion to the upper surface portion is not formed in the valve body 41 except for the vertical hole 45.

The supply passage 54 is provided in the surface portion of the valve body 41 located in the valve closing direction Z2 in this reference example . In other words, the supply passage 54 is realized by a groove provided in the lower surface portion of the valve body 41. The supply passage 54 extends from the vertical hole 45 to the outer peripheral surface portion along the radial direction when viewed in the valve opening direction Z1. As described above, the supply passage 54 is a passage surrounded by the groove formed in the valve body 41 and the upper surface portion of the orifice plate 26.

  Next, the operation of the fuel injection valve 10 will be described with reference to FIGS. 1 and 2. High pressure fuel pressurized by a fuel injection pump (not shown) is supplied to the lower body passage 29 through a pipe (not shown) connected to the high pressure opening 27. The high-pressure fuel supplied to the lower body passage 29 flows into the fuel reservoir chamber 21 through the nozzle body passage 20 and flows into the pressure control chamber 36 through the branch passage 34 and the in-orifice 38.

  When the coil 51 is not energized, the armature 42 closes the out orifice 37 by the biasing force of the coil spring 52. In this state, the high pressure fuel flowing into the pressure control chamber 36 is accumulated in the pressure control chamber 36 without being discharged to the low pressure side.

  A force in the valve opening direction Z1 acts on the needle 16 due to the fuel pressure of the high-pressure fuel in the fuel reservoir chamber 21, but the command piston 24 due to the fuel pressure of the high-pressure fuel in the pressure control chamber 36 acts on the needle 16. Since the sum of the force that presses the needle 16 in the valve closing direction Z2 and the force that the coil spring 25 presses the needle 16 in the valve closing direction Z2 is larger, the needle 16 maintains the valve closing state. For this reason, the communication between the fuel reservoir chamber 21 and the injection hole 18 is blocked, and fuel is not injected.

  In such a closed state, when the coil 51 is energized from a control device (not shown), a magnetic attractive force acts between the stator 50 and the armature 42, and the armature 42 is attracted to the stator 50. As a result, the ball valve 49 opens the out orifice 37. Then, the high pressure fuel in the pressure control chamber 36 is discharged from the out orifice 37. Since the out orifice 37 has a larger passage diameter than the in orifice 38, the fuel pressure in the pressure control chamber 36 decreases. The passage sectional area of the out orifice 37 is larger than the passage sectional area of the in orifice 38.

  The fuel discharged from the pressure control chamber 36 flows into the storage chamber 44 via the valve body chamber 48. Then, the fuel that has flowed into the storage chamber 44 flows down through the supply passage 54, and then is discharged to a low pressure side such as a fuel tank through a pipe connected to the low pressure opening 32 through the low pressure passage 30.

  When the fuel pressure in the pressure control chamber 36 decreases, the force that presses the needle 16 acting on the command piston 24 in the valve closing direction Z2 is weakened. Thereby, the force which pushes up the needle 16 in the valve opening direction Z1 becomes large, and the needle 16 moves in the valve opening direction Z1. As a result, the fuel reservoir chamber 21 and the injection hole 18 communicate with each other, and fuel is injected from the injection hole 18. Thus, by reciprocating the needle 16 in the axial direction Z, the nozzle hole 18 is opened and closed, and fuel injection from the nozzle hole 18 is interrupted.

As described above, in the fuel injection valve 10 of the present reference example , the supply passage 54 is provided on the injection hole 18 side (the lower Z2 side in FIG. 1) of the valve body 41, and the opposite side of the valve body 41 (FIG. 1). The disk portion 46 is disposed on the upper Z1 side). The valve body 41 has an outer peripheral surface portion in contact with the inner peripheral surface portion of the lower body 23, and an inner peripheral surface portion in contact with the outer peripheral surface portion of the armature 42. Further, since the passage extending in the axial direction Z other than the vertical hole 45 is not formed in the valve body 41, the valve body 41 is isolated from the valve chamber 53 which is a space on the opposite side to the space on the injection hole 18 side. ing. Therefore, the fuel discharged from the pressure control chamber 36 when the valve is opened and flowing through the supply passage 54 does not reach the opposite side of the valve body 41, and is discharged from the low pressure passage 30 to the outside of the lower body 23 through the supply passage 54. Is done. In other words, the valve body 41 functions as an isolation wall, the fuel flowing through the nozzle hole 18 does not flow around the disk portion 46, and the hydraulic pulsation of the fuel flowing through the nozzle hole 18 side is caused by the disk portion. 46 does not act. Therefore, in this reference example, it is possible to prevent the behavior of the armature 42 from becoming unstable due to the fuel acting on the disk portion 46. As a result, the armature 42 can be operated with high accuracy.

The valve chamber 53 disc portion 46 is disposed, since the passage of the fuel is in an isolated space, filling the present embodiment the oil as a fluid having a viscosity to such a valve chamber 53. Thereby, the periphery of the disk part 46 can be filled with oil. Therefore, the oil to be filled becomes a resistance against the vibration of the armature 42, and the vibration of the armature 42 can be suppressed.

(Second reference example )
Next, a second reference example of the present invention will be described with reference to FIGS. FIG. 5 is an example of an enlarged cross-sectional view of the main part of the fuel injection valve 10A of the second reference example . FIG. 6 is another example of an enlarged cross-sectional view of the main part of the fuel injection valve 10A of the second reference example . In this reference example , as shown in FIGS. 5 and 6, the configuration of the supply passage 54A formed in the valve body 41 is different from that of the first reference example described above.

  In the valve body 41, a supply passage 54 </ b> A through which fuel flows is formed separately from the vertical hole 45. When the armature 42 is opened, the supply passage 54A has the fuel passage 39 and the out orifice 37 without the fuel discharged from the out orifice 37 reaching the surface of the valve body 41 located in the valve opening direction Z1. Communicate with.

As shown in FIGS. 5 and 6, the supply passage 54 </ b> A has an upstream end opened to the storage chamber 44 and a downstream end opened to the lower surface of the valve body 41. Further, the downstream end of the supply passage 54 </ b> A opens into a space between the outer wall of the orifice plate 26 and the inner wall of the recess 33. Since this space constitutes the fuel passage 39, the supply passage 54A communicates with the fuel passage 39 when the valve is opened. Thus, the supply passage 54A is realized by a hole formed in the valve body 41, not a groove as in the first reference example . Among such supply passages 54 </ b> A, the supply passage 54 </ b> A shown in FIG. 5 has a bent shape in order to connect the storage chamber 44 and the lower surface portion of the valve body 41. Further, the supply passage 54 </ b> A shown in FIG. 6 has a shape in which a passage portion reaching the lower surface portion of the valve body 41 extends along the axial direction Z. The supply passage 54A shown in FIG. 6 is easy to form because the passage portion reaching the lower surface portion of the valve body 41 extends along the axial direction Z. Such a supply passage 54A can be realized by crossing a hole formed by a drill or the like in the valve body 41.

  As a result, the fuel discharged from the pressure control chamber 36 when the valve is opened flows into the storage chamber 44 via the valve body chamber 48. The fuel that has flowed into the storage chamber 44 flows down through the supply passage 54A, and then passes through the fuel passage 39 to the low pressure side of the fuel tank or the like through a pipe connected to the low pressure opening 32 through the low pressure passage 30. Discharged.

Thus, even with the supply passage 54A as in the present reference example , the same operations and effects as in the first reference example described above can be achieved.

( First embodiment )
Next, a first embodiment of the present invention will be described with reference to FIGS. FIG. 7 is an enlarged cross-sectional view of a main part of the fuel injection valve 10B of the first embodiment . FIG. 8 is a cross-sectional view showing the valve body 41 of the first embodiment . FIG. 9 is a plan view showing the valve body 41 of the first embodiment . In the present embodiment, as shown in FIG. 7, the configuration of the supply passage 54B formed in the valve body 41 is different from the first reference example described above.

A slit groove 60 is formed in the valve body 41 separately from the supply passage 54B. As shown in FIGS. 7 and 8, the supply passage 54 </ b> B has an upstream end that opens into the storage chamber 44, and a downstream end that opens into the lower surface of the valve body 41, as in the second reference example described above. To do. The downstream end portion of the supply passage 54 </ b> B is provided at the side surface side end portion of the valve body 41. Further, in the supply passage 54B, a passage portion 61 (hereinafter sometimes referred to as “first side passage 61”) reaching the lower surface portion of the valve body 41 has a shape extending along the axial direction Z. Therefore, as shown in FIG. 9, by forming a slit groove 60 by chamfering a part of the side surface portion of the valve body 41, a space formed by the side surface portion of the valve body 41 and the inner peripheral surface portion of the lower body 23 is obtained. , Part of the supply passage 54B. In other words, a portion not in contact with the inner peripheral surface portion of the lower body 23 is formed on the outer peripheral surface portion of the valve body 41, and these become a part of the supply passage 54B.

  In addition, a passage 62 (hereinafter sometimes referred to as “second side passage 62”) communicating with the upper surface portion of the valve body 41 is formed in the upstream portion of the side passage by a slit groove 60 extending in the axial direction Z. The In other words, by forming the slit groove 60, a first side passage 61 that constitutes a part of the supply passage 54B and a second side passage 62 that does not constitute the supply passage 54B are formed. The downstream end of the second side passage 62 opens to the upper surface of the valve body 41. Therefore, the valve chamber 53 and the fuel passage 39 communicate with each other through the slit groove 60. A plurality of such slit grooves 60 are formed on the side surface of the valve body 41 at intervals in the circumferential direction. As shown in FIG. 9, three slit grooves 60 are formed in the present embodiment.

  The downstream end portion of the second side passage 62 is provided at a position facing the remaining portion excluding the disc portion 46. In the present embodiment, the downstream side end portion of the second side passage 62 is provided at the side surface side end portion of the valve body 41. Therefore, as shown in FIG. Position. In other words, the position of the downstream end portion of the second side passage 62 is a position that does not overlap with the disk portion 46 when viewed in the axial direction Z.

  As a result, the fuel discharged from the pressure control chamber 36 when the valve is opened flows into the storage chamber 44 via the valve body chamber 48. The fuel that has flowed into the storage chamber 44 flows down through the supply passage 54B, and then passes through the fuel passage 39 to the low pressure side of the fuel tank or the like through a pipe connected to the low pressure opening 32 through the low pressure passage 30. Discharged. The fuel flowing into the storage chamber 44 flows down the supply passage 54B and then flows into the valve chamber 53 via the second side passage 62, and the valve chamber 53 is filled with fuel.

As described above, in the present embodiment, since the valve chamber 53 can be always filled with fuel, the fuel around the disk portion 46 can be always filled with fuel without being deficient. As a result, the fuel becomes a resistance against the vibration of the armature 42, and the vibration of the armature 42 can be suppressed. Therefore, unlike the first reference example described above, in this embodiment, it is possible to suppress deterioration of the fluid sealed in the valve chamber 53 due to long-term use. Also, the operation of sealing the fluid into the valve chamber 53 during assembly can be omitted.

  Further, since the opening of the second side passage 62 is formed at a position that does not face the disc portion 46, when fuel flows into the valve chamber 53, the external force caused by the inflow acts on the disc portion 46. It can be made as small as possible. Therefore, even if the flow amount becomes large, the external force acting on the disk portion 46 is small, so that it is possible to reliably prevent problems caused by the fuel flow and to always fill the valve chamber 53 with the fuel. Can do. Therefore, the supplied fuel becomes a resistance against the vibration of the armature 42, and the vibration of the armature 42 can be suppressed.

( Second Embodiment )
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 10 is a cross-sectional view showing a valve body 41C of the second embodiment . As shown in FIG. 10, the present embodiment is characterized in that the second reference example described above and the other reference example shown in FIG. 6 are combined with the first embodiment described above.

As in the first embodiment , the supply passage 54C has an upstream end that opens into the storage chamber 44 and a downstream end that opens into the lower surface of the valve body 41C. The supply passage 54C has a shape in which a passage portion reaching the lower surface portion of the valve body 41C extends along the axial direction Z. In addition, the slit groove 60 is formed in the valve body 41C as in the first embodiment . The valve chamber 53 and the fuel passage 39 communicate with each other through the slit groove 60. Therefore, unlike the above-described first embodiment , the slit groove 60 functions as a passage communicating the valve chamber 53 and the fuel passage 39 without forming the supply passage 54C.

  As a result, the fuel discharged from the pressure control chamber 36 when the valve is opened flows into the storage chamber 44 via the valve body chamber 48. The fuel that has flowed into the storage chamber 44 flows down the supply passage 54C, and then passes through the fuel passage 39 to the low pressure side of the fuel tank or the like through a pipe connected to the low pressure opening 32 through the low pressure passage 30. Discharged. The fuel flowing down the fuel passage 39 flows into the valve chamber 53 via the slit groove 60, and the valve chamber 53 is filled with fuel.

As described above, in the present embodiment, the opening on the downstream side of the passage communicating with the valve chamber 53 is formed at a position not facing the disk portion 46 by the slit groove 60 as in the first embodiment. Therefore, when the fuel flows into the valve chamber 53, it is possible to minimize the external force resulting from the flowing in from acting on the disk portion 46. Therefore, the same operations and effects as those of the first embodiment described above can be achieved.

  Further, since the fuel that has flowed down to the fuel passage 39 is supplied to the valve chamber 53 via the slit groove 60, when the fuel flows into the valve chamber 53, the external force caused by the flow-in can be reduced. As a result, the external force acting on the disk portion 46 can be further reduced.

(Third reference example )
Next, a third reference example of the present invention will be described with reference to FIG. FIG. 11 is an enlarged cross-sectional view of a main part of the fuel injection valve 10D of the third reference example . As shown in FIG. 11, this reference example is characterized in that the first reference example described above and the second reference example described above are combined.

The supply passage 54 is provided in the lower surface portion of the valve body 41 as in the first reference example described above. The valve body 41 is formed with a communication small hole 70 (second communication passage) communicating with the supply passage 54 and the valve chamber 53. The communication small hole 70 extends along the axial direction Z as shown in FIG. The downstream end portion of the communication small hole 70 opens at a position facing the disk portion 46. The passage sectional area of the communication small hole 70 is smaller than the passage sectional area of the supply passage 54.

As described above, in this reference example , the fuel flowing through the supply passage 54 flows into the valve chamber 53 through the communication small hole 70, but the passage sectional area of the communication small hole 70 is smaller than the passage sectional area of the supply passage 54. Therefore, the flow rate of flow is less than the fuel flowing through the supply passage 54. Therefore, since a very small amount of fuel flows into the valve chamber 53, the external force caused by the fuel flow hardly acts on the disk portion 46, so that no problem due to the fuel flow occurs.

  Further, since the valve chamber 53 can always be filled with fuel, the fuel around the disk portion 46 can be always filled with fuel without being deficient. As a result, the fuel becomes a resistance against the vibration of the armature 42, and the vibration of the armature 42 can be suppressed.

  Further, since the communication small hole 70 extends in the axial direction Z and the supply passage 54 extends in the radial direction, the communication small hole 70 and the supply passage 54 are orthogonal to each other. Accordingly, the fuel flowing down the supply passage 54 is unlikely to flow into the communication small hole 70, so that the external force due to the fuel flowing into the disk portion 46 can be further reduced.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

10, 10A, 10B, 10D ... Fuel injection valve 15 ... Nozzle body (housing)
16 ... Needle (valve member)
18 ... nozzle hole 20 ... passage for nozzle body (high pressure fuel passage)
23 ... Lower body (housing)
27 ... High-pressure opening (supply part)
29 ... Passage for lower body (high pressure fuel passage)
33 ... Recess (container)
34 ... Branch passage (high pressure fuel passage)
36 ... Pressure control chamber 37 ... Out orifice (first communication path)
39 ... Fuel passage (discharge passage)
41 ... Valve body (fixed part)
42 ... Armature (pressure control valve)
45 ... Vertical hole (through hole)
46 ... disk part (blade part)
51 ... Coil 52 ... Coil spring (elastic member)
53 ... Valve chamber (placement space)
54, 54A, 54B, 54C ... supply passage 60 ... slit groove (second communication passage)
70 ... Communication small hole (second communication passage)

Claims (1)

A cylindrical housing in which an injection hole through which fuel is injected is formed;
A valve member that is provided in the housing, opens and closes the injection hole by reciprocating in the axial direction of the housing, and intermittently injects fuel from the injection hole;
A supply section for supplying fuel with increased pressure into the housing;
A high-pressure fuel passage formed inside the housing and guiding the fuel supplied from the supply section to the nozzle hole;
A pressure control chamber formed inside the housing and supplied with the fuel flowing through the high-pressure fuel passage;
A first communication path connected to the pressure control chamber;
A storage chamber disposed downstream of the first communication path;
A discharge passage for discharging the fuel flowing into the storage chamber out of the housing;
Drive means for controlling the discharge of the fuel in the pressure control chamber to the storage chamber and the stop of the discharge by opening and closing the first communication path;
The pressure in the pressure control chamber acts on the end of the valve member located on the opposite side of the nozzle hole in the direction of closing the valve member,
The driving means includes
A fixed portion fixed to the inner peripheral surface portion of the housing;
A pressure control valve that is displaced in the axial direction with respect to the fixed portion and opens and closes the first communication path;
An elastic member that presses the pressure control valve in a direction to close the first communication path;
A coil that generates a magnetic force that attracts the pressure control valve to open the first communication path when energized,
A through hole is formed in the fixing portion so as to penetrate in the axial direction,
In the through hole, the pressure control valve is arranged to slide in the axial direction,
The end of the pressure control valve located on the side opposite to the nozzle hole side protrudes radially outward to restrict the displacement of the pressure control valve to the side opposite to the nozzle hole side with respect to the fixed part. Feather part is provided,
The outer peripheral surface portion of the fixed portion and the inner peripheral surface portion of the housing are in contact with each other,
The inner peripheral surface portion of the fixed portion and the outer peripheral surface portion penetrating the through hole of the pressure control valve are in contact with each other,
The fixing portion is formed with a supply passage that extends in a radial direction from the through hole and reaches the discharge passage without reaching the surface portion of the fixing portion that is located on the side opposite to the nozzle hole side,
A plurality of slit grooves (60) are formed as second communication paths at intervals in the circumferential direction on the side surface of the fixed part, and an arrangement space (53) in which the blade part is disposed by the second communication path. The discharge passage (39) is in communication;
The opening on the downstream side of the passage communicated with the arrangement space by the second communication passage is configured to reduce the external force acting on the blade portion caused by the flow of fuel when the fuel flows into the arrangement space. Formed at a position not facing the blade,
If the pressure control valve is open, the fuel discharged from the first communication passage flows down the supply passage, the discharge passage to the optimum Rutotomoni, the arrangement space through the second communication passage a fuel injection valve, characterized in that leads to.

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