JP2006250087A - Three-way solenoid valve, and fuel injection device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-way solenoid valve, capable of being smaller in size, and a fuel injection device using this. <P>SOLUTION: This three-way solenoid valve 30 switches supply and discharge of high pressure fluid for controlling pressure in a supplied chamber 19. It is provided with a housing 10 having a high pressure side opening part 22, a low pressure side opening part 23, and a supply side opening part 24, and including fluid sump chambers 20 and 21, a first valve element 33 to connect/disconnect a high pressure passage 13 and a low pressure passage 14 to the supply passage 15, a second valve element 34 movable roughly perpendicularly to an opening surface of the low pressure side opening part 23 to open/close the low pressure side opening part 23, an armature 32 provided on the counter-passage side of the second valve element 34 to the low pressure passage 14 to simultaneously move the first valve element 33 and the second valve element 34, and an electromagnetic coil 31 to move the armature 32 by magnetic force to disconnect the high pressure passage 13 and the low pressure passage 14 from the supply passage 15 for opening the low pressure side opening part 23 by the second valve element 34. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a three-way solenoid valve and a fuel injection device using the same.

  Conventionally, a three-way solenoid valve using a ball valve is known as a three-way solenoid valve used to control the pressure in a pressure control chamber provided in a fuel injection device (Patent Document 1). As shown in FIG. 9, the three-way solenoid valve described in this document includes a storage chamber 150 that stores the ball valve 110, a high-pressure passage 160 that communicates with the storage chamber 150, a low-pressure passage 170, and a pressure control chamber 190. It comprises a housing 200 in which a communicating passage 180 is formed, an armature 120 having a push rod 130 for moving the ball valve 110 to the high-pressure passage 160, and an electromagnetic coil 100 that attracts the armature 120.

This three-way solenoid valve controls the pressure in the pressure control chamber 190 by switching the communication passage 180 and the high-pressure passage 160 or the communication passage 180 and the low-pressure passage 170 with the ball valve 110. When the electromagnetic coil 100 is excited, a magnetic force is generated in the coil 100, the armature 120 is attracted, the push rod 130 moves the ball valve 110 in the direction of the high pressure passage 160, and the ball valve 110 closes the high pressure passage 160. . As a result, the communication passage 180 and the low pressure passage 170 communicate with each other, and the fuel in the pressure control chamber 190 escapes via the low pressure passage 170, so that the pressure in the pressure control chamber 190 decreases. On the other hand, when the excitation of the electromagnetic coil 100 is released, the ball valve 110 again closes the low pressure passage 170, so that the communication passage 180 and the high pressure passage 160 communicate with each other, and the high pressure fuel in the high pressure passage 160 communicates. It flows into the pressure control chamber 190 via the passage 180. As a result, the pressure in the pressure control chamber 190 increases.
JP-A-1-257755

  The flow passage cross-sectional areas of the high pressure passage 160, the low pressure passage 170, and the communication passage 180 formed in the housing 200 of the three-way solenoid valve have an optimum flow rate in consideration of the pressure control responsiveness of the pressure control chamber 190. It is prescribed as follows.

  However, as shown in FIG. 9, in the three-way solenoid valve, since the push rod 130 is provided in the low pressure passage 170, in order to optimize the flow rate of the fuel flowing through the low pressure passage 170, in addition to the above sectional area, The cross-section integral of the push rod 130 is required. As a result, the passage diameter of the low pressure passage 170 is increased. As the passage diameter increases, the diameter of the ball valve 110 must also be increased. If the diameter of the ball valve 110 is increased, the accommodation chamber 150 that accommodates the ball valve 110 must be enlarged. As a result, there is a problem that the size of the three-way solenoid valve is increased.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a three-way solenoid valve capable of reducing the size and a fuel injection device using the same.

  To achieve the above object, according to the three-way solenoid valve according to claim 1 of the present invention, the supply of the high-pressure fluid from the high-pressure source to the supply chamber and the discharge of the high-pressure fluid from the supply chamber to the low-pressure source are performed. A three-way solenoid valve for switching and controlling the pressure in the supplied chamber, one end connected to the high pressure source, one end connected to the low pressure source, and one end connected to the supplied chamber And a fluid reservoir chamber having a high pressure side opening connected to the high pressure passage, a low pressure side opening connected to the low pressure passage, and a supply side opening connected to the supply passage. A housing formed, a first valve body provided in the fluid reservoir chamber and communicating and blocking the high-pressure passage and the low-pressure passage, and the high-pressure passage and the supply passage; and an opening of the low-pressure side opening provided in the fluid reservoir chamber Open the low-pressure side Generated by energizing a second valve body that opens and closes a portion, an armature that is provided on the opposite side of the low pressure passage of the second valve body, and that moves the first valve body and the second valve body simultaneously An electromagnetic coil that moves the armature by the magnetic force that is applied, blocks the communication between the high pressure passage and the low pressure passage, and the high pressure passage and the supply passage by the first valve body, and opens the low pressure side opening by the second valve body. It is characterized by having.

  According to this configuration, the armature that moves the second valve body in a direction substantially perpendicular to the opening surface of the low-pressure side opening is provided on the opposite side of the low-pressure passage of the second valve body and moves together with the first valve body. Therefore, the diameter of the low-pressure side opening can be determined without taking into account the amount of the member for moving the valve body, and the diameter of the low-pressure side opening should be the minimum necessary diameter. it can. If the diameter of the low-pressure side opening can be made the minimum necessary diameter, the physique of the valve body itself can be reduced in size, and the physique of the three-way solenoid valve can also be reduced in size.

  According to the three-way solenoid valve according to claim 2 of the present invention, the armature is provided between the first valve body and the second valve body, and the first valve body has a high pressure together with the armature and the second valve body. When the second valve body is moved in a direction substantially perpendicular to the opening surface of the side opening, opens and closes the high pressure side opening, and the second valve body closes the low pressure side opening, the high pressure fluid from the high pressure passage acts. The second valve body includes a pressure receiving surface that generates a force in a direction to open the low pressure side opening.

  According to this configuration, the armature is provided between the first valve body and the second valve body, and the first valve body is substantially perpendicular to the opening surface of the high-pressure side opening as in the second valve body. Therefore, the high pressure fluid flowing from the high pressure passage acts on the first valve body, and the first valve body includes the armature and the second valve body. A force is generated to move the lens in the direction of the low pressure side opening.

  However, when the low pressure side opening is closed, the second valve body has a pressure receiving surface on which high pressure fluid acts to generate a force in a direction to open the low pressure side opening. Yes. Since the direction of the force generated by the pressure receiving surface is opposite to the direction of the force generated in the first valve body, a part of the force generated in the first valve body is canceled out. As a result, only a force in the direction of the low pressure side opening corresponding to the diameter of the low pressure side opening is generated in each valve body and armature.

  Therefore, if the diameter of the opening on the low pressure side is set to the minimum necessary diameter, the magnetic force generated in the electromagnetic coil for moving the armature should be smaller than the magnetic force generated in the electromagnetic coil of the conventional three-way solenoid valve. Is possible. As a result, the physique of the electromagnetic coil can be reduced, and as a result, the physique of the three-way solenoid valve can be reduced.

  According to the three-way solenoid valve according to claim 3 of the present invention, in the three-way solenoid valve according to claim 2, the fluid reservoir chamber is connected to the high-pressure side fluid reservoir chamber to which the high pressure passage is connected and which houses the first valve body. The low-pressure passage and the supply passage are connected to each other and the low-pressure side fluid reservoir chamber that houses the second valve body. The housing has a first communication passage that connects the high-pressure side fluid reservoir chamber and the low-pressure side fluid reservoir chamber. The outer diameter of the first valve body is smaller than the outer diameter of the second valve body, and the second valve body closes the low pressure side opening in a state where no magnetic force is generated in the electromagnetic coil. As described above, the outer diameters of the first valve body and the second valve body and the area of the pressure receiving surface of the second valve body are adjusted.

  According to this configuration, the fluid reservoir chamber is divided into two, each valve body is accommodated in each reservoir chamber, each fluid reservoir chamber is connected by the first communication path, and the first valve body and the second valve body are connected. By adjusting the outer diameter, it is possible to freely determine the areas of the end surface of the first valve body on which the high-pressure fluid acts and the pressure receiving surface of the second valve body. As a result, the direction and magnitude of the force generated in the armature can be freely determined.

  Furthermore, in claim 3, the second valve body has a low-pressure side opening in a state where the outer diameter of the first valve body is smaller than the outer shape of the second valve body and no magnetic force is generated in the electromagnetic coil. The outer diameter of the second valve body and the area of the pressure receiving surface of the second valve body are adjusted so as to close the valve. Therefore, when energizing the electromagnetic coil to generate magnetic force and moving the armature in the direction of the opening on the anti-low pressure side, the magnitude of the force generated in the armature is small, so the magnitude of the magnetic force generated in the electromagnetic coil is also small. It becomes possible to do. As a result, the physique of the electromagnetic coil can be further reduced in size, and as a result, the physique of the three-way electromagnetic valve can also be reduced in size.

  According to the three-way solenoid valve according to claim 4 of the present invention, in the three-way solenoid valve according to claim 2, the fluid reservoir chamber is connected to the high-pressure side fluid reservoir chamber to which the high-pressure passage is connected and which houses the first valve body. A low-pressure passage and a supply passage are connected to each other, and a low-pressure side fluid reservoir chamber that accommodates the second valve body. The high-pressure passage is provided in each of the first valve body, the second valve body, and the armature. A second communication passage is formed to connect the side fluid reservoir chamber and the low pressure side fluid reservoir chamber, the outer diameter of the first valve body is smaller than the outer diameter of the second valve body, and magnetic force is applied to the electromagnetic coil. The outer diameter of the first valve body and the second valve body and the area of the pressure receiving surface of the second valve body are adjusted so that the second valve body closes the low-pressure side opening in a state where it does not occur. It is characterized by being.

  According to this configuration, as the communication path that connects the high-pressure side fluid reservoir chamber and the low-pressure side fluid reservoir chamber, the second valve body that penetrates through each of the first valve body, the armature, and the second valve body is provided. A communication path is formed. Thereby, since it is not necessary to form the communication path in the housing, it is possible to prevent a decrease in strength of the housing.

  According to the three-way solenoid valve of the fifth aspect of the present invention, the armature is provided on the side opposite to the low pressure side of the first valve body, and the second valve body is provided on the side of the low pressure side opening of the first valve body. The fluid reservoir chamber has a dividing wall that is divided into a high pressure fluid reservoir chamber having a high pressure side opening and a low pressure fluid reservoir chamber having a low pressure side opening and a supply side opening. A groove passage is formed in the side wall of the first valve body so that the high-pressure side fluid reservoir chamber and the low-pressure side fluid reservoir chamber can communicate with each other, and the first valve body and the second valve body penetrate through the dividing wall. When the first valve body and the second valve body are movably supported in the same direction as the movement direction of the second valve body and the second valve body closes the low pressure side opening, When the fluid in the room flows into the low pressure side fluid reservoir chamber via the groove passage and the armature moves more than a predetermined amount, the fluid in the high pressure side fluid reservoir chamber is Body, is characterized in that it is formed at a position where the inflow to the low pressure side fluid reservoir chamber is prevented through the groove passage.

  According to this configuration, the fluid reservoir chamber is formed with a partition wall that divides into the high-pressure side and the low-pressure side fluid reservoir chamber, and the first valve body and the second valve body are provided so as to penetrate the partition wall, The first valve body and the second valve body were supported by the dividing wall. When the second valve body closes the low pressure side opening, the fluid reservoir chambers communicate with each other on the side wall of the first valve body, and the second valve body closes the low pressure side opening. In this case, a groove passage is formed so as to block the fluid reservoir chambers from each other.

  Thereby, even if the high pressure fluid from the high pressure passage acts on the first valve body, the first valve body does not generate a force to move the first valve body. The magnetic force generated in the electromagnetic coil for moving in the direction can be reduced. As a result, the physique of the electromagnetic coil can be reduced, and as a result, the physique of the three-way solenoid valve can be reduced.

  According to the fuel injection device of the sixth aspect of the present invention, the nozzle valve member for opening and closing the nozzle hole and the nozzle valve member are supported so as to be reciprocally movable, and the fuel pressure is applied to the nozzle valve member in the nozzle hole closing direction. A nozzle main body in which a control chamber is formed, and the three-way solenoid valve according to any one of claims 1 to 5 that controls fuel pressure in the control chamber.

  According to this configuration, the three-way electromagnetic valve according to any one of claims 1 to 5 is supported such that the nozzle valve member that opens and closes the nozzle hole and the nozzle valve member are reciprocally movable, and the nozzle valve member The fuel injection device is applied as an electromagnetic valve for controlling the pressure in the control chamber of the fuel injection device provided with a nozzle body in which a control chamber for applying fuel pressure in the nozzle hole closing direction is formed. Can also be miniaturized. As a result, the mountability of the fuel injection device to the internal combustion engine is improved.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration of a fuel injection device to which the present invention is applied. For example, the fuel injection device is suitably used for a common rail injection system of a diesel engine.

  The fuel injection device 1 starts or stops fuel injection by opening and closing a nozzle hole 17 provided at the tip (lower end in the figure) of a body 10 as a nozzle body by vertical movement of a nozzle needle 25 as a nozzle valve member. The operation is controlled by a control device (not shown).

  The nozzle hole 17 is opened when the nozzle needle 25 is at the upper end position, and is connected to the fuel reservoir chamber 18 following the high-pressure fuel passage 13 to be supplied with fuel. The nozzle hole 17 is closed when the nozzle needle 25 is at the lower end position where the nozzle needle 25 is seated on the nozzle seat 26, the conduction with the fuel reservoir chamber 18 is cut off, and the fuel supply is stopped.

  The high-pressure fuel passage 13 as a high-pressure passage extends upward from the fuel reservoir chamber 18 and communicates with an external passage that reaches an external common rail 39 via an inlet 11 provided on the upper portion of the body 10. The common rail 39 is connected to a high-pressure pump 40 that pumps fuel from the fuel tank 41 and pressurizes the fuel, and accumulates pressurized high-pressure fuel. A drain passage 14 as a low-pressure passage for returning fuel is formed in the body 10. The drain passage 14 is an external passage that reaches an external fuel tank 41 via an outlet 12 provided on the upper side of the body 10. Communicating with A control chamber 19 is formed above the nozzle needle 25. The nozzle needle 25 is urged in the valve closing direction (downward) by the spring force of the spring 28 disposed in the control chamber 19 and the fuel pressure in the control chamber 19.

  The common rail 39 corresponds to the high pressure source described in the claims. The fuel tank 41 corresponds to the low pressure source described in the claims. The control room 19 corresponds to the supplied room described in the claims.

  The fuel pressure in the control chamber 19 is controlled by a three-way solenoid valve 30. The three-way solenoid valve 30 includes an electromagnetic coil 31, an armature 32, a high pressure side valve body 33 as a first valve body, and a low pressure side valve body 34 as a second valve body. The high pressure side valve element 33 and the low pressure side valve element 34 are formed on the upper end surface and the lower end surface of the armature 32, respectively. Both valve bodies 33 and 34 move with the movement of the armature 32. The armature 32 moves upward or downward by the magnetic force generated by the electromagnetic coil 31 or the pressure of the high pressure fuel in the high pressure fuel passage 13. The electromagnetic coil 31 generates a magnetic force when a drive current is applied from the control device.

  The high pressure side valve element 33 is accommodated in the high pressure side valve chamber 20. As shown in FIGS. 1 and 2, the high pressure side valve body 33 is movable upward or downward on the side wall of the through hole formed in a part of the body 10 forming the high pressure side valve chamber 20. It is supported by. The high-pressure side valve chamber 20 includes a high-pressure port 22 as a high-pressure side opening at a position facing the end face of the high-pressure side valve body 33, and the high-pressure fuel passage 13 is connected to the high-pressure port 22. High pressure fuel flows into the high pressure side valve chamber 20 from the high pressure fuel passage 13.

  The low pressure side valve body 34 is accommodated in the low pressure side valve chamber 21. As shown in FIGS. 1 and 2, the low pressure side valve body 34 can move upward or downward on the side wall of the through hole formed in a part of the body 10 forming the low pressure side valve chamber 21. It is supported by. The low pressure side valve chamber 21 includes a control port 24 as a supply side opening and a drain port 23 as a low pressure side opening at a position facing the end surface of the low pressure side valve body 34. A fuel passage 15 as a passage is connected, and a drain passage 14 is connected to the drain port 23. The fuel passage 15 communicates with the control chamber 19 through the orifice 27. Further, the body 10 is formed with a communication path 16 as a first communication path that connects the high-pressure side valve chamber 20 and the low-pressure side valve chamber 21. The high-pressure fuel that has flowed into the high-pressure side valve chamber 20 also flows into the low-pressure side valve chamber 21 through the communication path 16. In the present embodiment, the high-pressure side valve chamber 20 and the low-pressure side valve chamber 21 correspond to the fluid reservoir chamber described in the claims.

  When the armature 32 moves upward together with the valve bodies 33 and 34, the high pressure side valve body 33 closes the high pressure port 22, and the low pressure side valve body 34 opens the drain port 23. As a result, the communication between the control chamber 19 and the high-pressure fuel passage 13 is cut off, and the communication between the control chamber 19 and the drain passage 14 is released, and the fuel in the control chamber 19 is returned to the fuel tank via the drain passage 14. . As a result, the fuel pressure in the control chamber 19 decreases. When the fuel pressure in the control chamber 19 decreases, the nozzle needle 25 rises away from the nozzle seat 26.

  On the contrary, when the armature 32 moves downward together with the valve bodies 33 and 34, the high pressure side valve body 33 opens the high pressure port 22, and the low pressure side valve body 34 closes the drain port 23. As a result, the communication between the control chamber 19 and the high-pressure fuel passage 13 is released and the communication between the control chamber 19 and the drain passage 14 is blocked, and the high-pressure fuel in the high-pressure fuel passage 13 is supplied to the control chamber 19. Therefore, the fuel pressure in the control chamber 19 increases. When the fuel pressure in the control chamber 19 rises, the nozzle needle 25 is seated on the nozzle seat 26.

  Further, by appropriately changing the diameters of the high pressure port 22, the drain port 23, and the control port 24, the flow rate characteristics of the fuel flowing through the ports 22, 23, 24 are changed. When the flow characteristics of the fuel flowing through the ports 22, 23, 24 change, the responsiveness of the operation of the nozzle needle 25 changes, so that the pressure of the high-pressure fuel flowing through the high-pressure fuel passage 13 and the internal combustion engine on which the fuel injection device 1 is mounted. It is necessary to determine according to the specifications. The three-way solenoid valve 30 will be described in detail later.

(About three-way solenoid valve)
Next, the three-way solenoid valve 30 of this embodiment is demonstrated based on FIG. 2 and FIG. FIG. 2 is a cross-sectional view of a main part of the three-way solenoid valve in the first embodiment in a state where energization to the electromagnetic coil is stopped. FIG. 3 is a cross-sectional view of the main part of the three-way solenoid valve in the first embodiment in a state where current is supplied to the electromagnetic coil.

  As shown in FIG. 2, in the state where the drive current is not supplied from the control device to the electromagnetic coil 31, the armature 32 is placed in the direction of the drain port 23 by the pressure of the high pressure fuel flowing from the high pressure port 22. A force F to be moved (downward) is generated.

  At the upper end of the armature 32, the end face of the high pressure side valve element 33 is formed so as to face the high pressure port 22. The high-pressure side valve element 33 prevents the high-pressure fuel from flowing into the high-pressure side valve chamber 20 from the high-pressure fuel passage 13 by being seated on the high-pressure port 22, and is separated from the high-pressure side valve chamber 20. Inflow of high-pressure fuel is permitted.

  When the high pressure port 22 is open, the high pressure side valve body 33 is formed with a pressure receiving surface A1 and a pressure receiving surface A2 for receiving the pressure of the high pressure fuel. When the high pressure fuel acts on these surfaces A1 and A2, the high pressure side A force is generated to move the side valve body 33 downward. The pressure receiving surface A1 is formed in the vicinity of the central axis of the high pressure side valve body 33, the outer diameter of which is substantially the same as the diameter of the high pressure port 22, and the pressure receiving surface A2 is on the outer side of the pressure receiving surface A1 and on the high pressure side. It is a surface formed between the outer periphery of the valve body 33.

  When the drain port 23 is open, the low pressure side valve body 34 is formed with a pressure receiving surface A3 and a pressure receiving surface A4 for receiving the pressure of the fuel in the low pressure side valve chamber 21, and the low pressure side valve chamber 21 is formed on these surfaces. When the pressure of the fuel acts, a force is generated to move the low pressure side valve body 34 toward the high pressure port 22 (upward). The pressure receiving surface A3 is formed in the vicinity of the central axis of the low pressure side valve body 34, and the outer diameter of the pressure receiving surface A3 substantially matches the diameter of the drain port 23. The pressure receiving surface A4 is a surface formed between the outside of the pressure receiving surface A3 and the outer periphery of the low pressure side valve body 34.

  In a state where the drive current is not supplied to the electromagnetic coil 31 from the control device, the high pressure fuel from the high pressure fuel passage 13 acts on the high pressure side valve body 33 on the surface obtained by adding the pressure receiving surface A1 and the pressure receiving surface A2. A force F1 is generated to lower the high pressure side valve body 33 downward. On the other hand, the high-pressure fuel that has flowed into the low-pressure side valve chamber 21 via the communication passage 16 acts on the pressure-receiving surface A4 to the low-pressure side valve body 34 to push the low-pressure side valve body 34 upward. A force F2 in the direction opposite to F1 is generated.

  Accordingly, the armature 32 generates a force F obtained by subtracting the force F2 from the force F1. Thereby, the low pressure side valve body 34 can close the drain port 23. At this time, the high-pressure fuel that has flowed into the low-pressure side valve chamber 21 flows into the control chamber 19 via the control port 24 and the fuel passage 15, and the fuel pressure in the control chamber 19 increases. It should be noted that the force F2 obtained by subtracting the force F1 from the force F2 can be maintained with the low pressure side valve body 34 closing the drain port 23 so that the force F2 is smaller than the force F1. The pressure receiving surfaces A1, A2, A3, and A4 are defined.

  As shown in FIG. 3, when a drive current is applied to the electromagnetic coil 31 from the control device, a magnetic force Fs that pulls up the armature 32 is generated in the electromagnetic coil 31. The magnetic force Fs exceeds the force F, and the armature 32 is pulled up by the magnetic force Fs. When the armature 32 is pulled up, the high-pressure side valve element 33 is seated on the high-pressure port 22, closes the high-pressure port 22, and prevents high-pressure fuel from flowing into the high-pressure side valve chamber 20 from the high-pressure fuel passage 13.

  At the same time, the low pressure side valve body 34 opens the drain port 23, the drain passage 14 and the control chamber 19 communicate with each other, and the fuel in the control chamber 19 is discharged to the drain passage 14. Thereafter, the fuel pressure in the control chamber 19 decreases. At this time, in the armature 32, the high pressure fuel acts on the pressure receiving surface A1 of the high pressure side valve body 33, and a force F3 is generated to lower the armature 32 downward.

  Again, when the drive current from the control device to the electromagnetic coil 31 is not energized, the magnetic force Fs becomes zero, and only the force F3 acts on the armature 32. It moves downward by force F3. When the armature 32 moves downward and the high pressure side valve element 33 opens the high pressure port 22, the high pressure fuel also acts on the pressure receiving surface A2 and accelerates the moving speed of the armature 32. The armature 32 stops when the low pressure side valve body 34 closes the drain port 23. At this time, the high pressure fuel acts again on the pressure receiving surface A4 of the low pressure side valve body 34, and the low pressure side valve body 34 generates a force F2 that pushes the low pressure side valve body 34 upward. Since the force F1 acting on the side valve body 33 is greater, both the valve bodies 33 and 34 and the armature 32 are maintained in the state shown in FIG.

  In the present embodiment, the armature 32 supporting the low pressure side valve body 34 is provided on the side opposite to the drain passage. In other words, the armature 32 supporting the low pressure side valve body 34 is disposed in the drain passage. Therefore, it is not necessary to determine the diameter of the drain port 23 in consideration of the diameter of the armature 32. The diameter of the drain port 23 may be a diameter corresponding to the flow rate characteristic of the fuel flowing through the drain port 23 as described above. As a result, the diameter of the drain port 23 can be set to the minimum necessary diameter, and the size of the low-pressure side valve body 34 that opens and closes the drain port 23 can be reduced. As a result, the size of the three-way solenoid valve 30 can also be reduced.

  Further, in this embodiment, when the drain port 23 is closed by the low pressure side valve body 34, the high pressure side valve body 33 has a high pressure from the high pressure fuel passage 13 on the end surface (the pressure receiving surface A 1 and the pressure receiving surface A 2). The fuel acts to generate a force F1 for lowering the high-pressure side valve element 33 downward. At the same time, the low pressure side valve body 34 is formed with a pressure receiving surface A4 on which high pressure fuel acts. When high pressure fuel acts on the pressure receiving surface A4, a force F2 is generated in the low pressure side valve body 34 in a direction to push up the low pressure side valve body 34 and open the drain port 23. The force F2 is opposite in direction to the force F1 and has a smaller magnitude than the force F1, so that a part of the force F1 generated in the high-pressure side valve body 33 is canceled by the force F2. As a result, force is generated in the valve bodies 33 and 34 and the armature 32 when high pressure fuel acts on the diameter of the pressure receiving surface A3 of the low pressure side valve body 34. The direction of the force is a direction in which the valve bodies 33 and 34 and the armature 32 are to be lowered.

  Accordingly, if the diameter of the drain port 23 is set to the minimum necessary diameter, the force F for lowering the armature 32 can be reduced, and the electromagnetic coil 31 for moving the armature 32 upward is generated. The magnetic force Fs can be reduced. As a result, the physique of the electromagnetic coil 31 can be reduced in size, and the physique of the three-way electromagnetic valve 30 can also be reduced in size.

  Further, by accommodating the valve bodies 33 and 34 in the respective valve chambers 20 and 21, connecting the valve chambers 20 and 21 with each other through the communication passage 16, and adjusting the outer diameters of both the valve bodies 33 and 34, The areas of the pressure receiving surfaces A1 and A2 of the high pressure side valve body 33 and the area of the pressure receiving surface A4 of the low pressure side valve body 34 can be freely determined. As a result, the direction and magnitude of the force generated in the armature 32 can be freely determined.

  In the present embodiment, the outer diameter of the high-pressure side valve element 33 is smaller than the outer diameter of the low-pressure side valve element 34, and the low-pressure side valve element 34 is drained in a state where no drive current is supplied to the electromagnetic coil 31. Since the area of the pressure receiving surface A4 of the low pressure side valve body 34 is adjusted so as to close the port 23, the magnitude of the force generated in the armature 32 can be arbitrarily set. For this reason, the force of the magnetic force Fs generated in the electromagnetic coil 31 when the armature 32 is moved can be reduced. Therefore, the physique of the electromagnetic coil 31 can be further reduced, and as a result, the physique of the three-way electromagnetic valve 30 can also be reduced.

  Further, in this embodiment, since the low-pressure side valve element 34 generates the force F in the direction in which the drain port 23 is closed in the armature 32 in a state where the drive current is not supplied to the electromagnetic coil 31, A member for urging the bodies 33 and 34 and the armature 32 is not necessary.

  Further, in the present embodiment, the valve bodies 33 and 34 and the armature 32 are integrally formed, so that the armature 120 and the ball valve 110 are formed separately as in the prior art shown in FIG. Compared to the case, the dimensional tolerance can be reduced.

  Further, in the present embodiment, it is not necessary to make the shape of the armature 32 for moving both valve bodies 33 and 34 match the diameter of the drain port 23, so that the strength of the armature 32 can be ensured, and the armature It is possible to prevent the buckling deformation and compression deformation of 32.

  In this embodiment, the three-way solenoid valve 30 of the present invention has been described as an example applied to the fuel pressure control in the control chamber 19 of the fuel injection device 1. Accordingly, if the size of the three-way solenoid valve 30 can be reduced, the size of the fuel injection device 1 can also be reduced. As a result, the mountability of the fuel injection device 1 to the internal combustion engine is improved.

  In the present embodiment, even when the fuel pressure is low, the armature 32 generates a force sufficient to keep the drain port 23 closed. Even if the fuel pressure from the high-pressure fuel passage 13 is relatively low, the fuel flows into the control chamber 19 without being discharged from the drain port 23, so that the pressure in the control chamber 19 is quickly increased. It becomes possible.

(Second Embodiment)
A second embodiment is shown in FIGS. FIG. 4 is a cross-sectional view of the main part of the three-way solenoid valve according to the second embodiment of the present invention. FIG. 5 is a radial cross-sectional view of the armature of the three-way solenoid valve in the second embodiment. In addition, the same function thing as 1st Embodiment attaches | subjects the same code | symbol. Here, only the feature points different from the first embodiment will be described.

  As shown in FIGS. 4 and 5, the high-pressure side valve body 33, the armature 32, and the low-pressure side valve body 34 are formed with a valve body communication passage 35 that penetrates the inside thereof. This valve body communication path 35 has the same function as the communication path 16 of the first embodiment in the second communication path described in the claims, and connects the high pressure side valve chamber 20 and the low pressure side valve chamber 21 to the high pressure side. The high pressure fuel that has flowed into the valve chamber 20 is caused to flow into the low pressure side valve chamber 21.

  According to this configuration, the high-pressure side valve body 33, the armature 32, and the low-pressure side valve body 34 are formed with the valve body communication passage 35 penetrating through them, so that a communication passage is formed in the body 10. Since it is not necessary, it is possible to prevent the strength of the body 10 from decreasing.

(Third embodiment)
A third embodiment is shown in FIGS. FIG. 6 is a cross-sectional view of a main part of the three-way solenoid valve in the third embodiment in a state where energization to the electromagnetic coil is stopped. FIG. 7 is a radial cross-sectional view of the armature of the three-way solenoid valve in the third embodiment. FIG. 8 is a cross-sectional view of a main part of the three-way solenoid valve in the third embodiment in a state where current is supplied to the electromagnetic coil. In addition, the same function thing as 1st Embodiment attaches | subjects the same code | symbol. Here, only the feature points different from the first embodiment will be described.

  As shown in FIG. 6, the valve bodies 33 and 34 and the armature 32 are integrally formed from the drain port 23 in the order of the low pressure side valve body 34, the high pressure side valve body 33, and the armature 32. These parts are accommodated in a space provided in the body 10. The body 10 is formed with a dividing wall 29 that divides this space into two. The dividing wall 29 is formed with a through-hole penetrating in the vertical direction of the body 10. In the through-hole, the valve body 33, 34 and the armature 32 integrally formed are inserted and supported so as to be movable in the vertical direction of the body 10.

  The space above the dividing wall 29 is the high-pressure side valve chamber 20, and the space below is the low-pressure side valve chamber 21. A high pressure port 22 is formed in the high pressure side valve chamber 20 and a high pressure fuel passage 13 is connected thereto. A drain port 23 and a control port 24 are formed in the low pressure side valve chamber 21, a drain passage 14 is connected to the drain port 23, and a fuel passage 15 is connected to the control port 24.

  As shown in FIG. 6, a groove passage 36 is formed on the side surface of the high pressure side valve body 33. The groove passage 36 is formed in a direction along the moving direction of the valve body 33, and as shown in FIG. 7, a guide that contacts the dividing wall 29 is provided between the groove passage 36 and the adjacent groove passage 36. A portion 37 is formed. In the groove passage 36, the high-pressure fuel that flows into the high-pressure side valve chamber 20 flows into the low-pressure side valve chamber 21 through the groove passage 36 when the low-pressure side valve body 34 closes the drain port 23. It is formed in the position and the length.

  On the upper side of the armature 32, a spring 38 that generates a force for lowering the armature 32 and an electromagnetic coil 31 are provided.

  FIG. 6 shows a state where the drive current from the control device is not supplied to the electromagnetic coil 31. At this time, the high-pressure side valve chamber 20 and the low-pressure side valve chamber 21 are filled with high-pressure fuel. High pressure fuel acts on the upper and lower ends of the groove passage 36 of the high pressure side valve body 33 and a part of the end surface of the low pressure side valve body 34. The low pressure side valve body 34 generates a force in a direction to push the low pressure side valve body 34 upward by the high pressure fuel that has acted on a part of the end face. In the high pressure side valve element 33, the high pressure fuel acts uniformly on the upper and lower ends of the groove passage 36, and therefore no force is generated to move the high pressure side valve element 33. Therefore, the armature 32 generates a force F4 obtained by subtracting the upward force generated in the low-pressure side valve body 34 from the force of the spring 38 that attempts to lower the armature 32 downward.

  As shown in FIG. 8, when a drive current from the control device is supplied to the electromagnetic coil 31, a magnetic force Fs that pulls up the armature 32 is generated in the electromagnetic coil 31. The magnetic force Fs exceeds the force F4, and the armature 32 is pulled up by the magnetic force Fs. When the armature 32 is pulled up, the lower end portion of the groove passage 36 of the high pressure side valve element 33 is pulled up to the side wall of the dividing wall 29, the communication between the high pressure side valve chamber 20 and the low pressure side valve chamber 21 is cut off, and the high pressure fuel Inflow to the low pressure side valve chamber 21 is prevented.

  At the same time, the low pressure side valve body 34 opens the drain port 23, the drain passage 14 and the control chamber 19 communicate with each other, and the fuel in the control chamber 19 is discharged to the drain passage 14. Thereafter, the fuel pressure in the control chamber 19 decreases.

  Again, when the electromagnetic coil 31 returns to the state where the drive current from the control device is not energized, the magnetic force Fs becomes zero, and only the force of the spring 38 acts on the armature 32. The force moves downward, and the low pressure side valve body 34 closes the drain port 23 again.

  In this embodiment, the dividing wall 29 is formed in the body 10, the upper side of the dividing wall 29 is the high-pressure side valve chamber 20, and the lower side is the low-pressure side valve chamber 21, and the through-hole formed in the dividing wall 29 is Inserted from the drain port 23 is a low-pressure side valve body 34, a high-pressure side valve body 33, and an armature 32 in this order, and is supported by the dividing wall 29. When the low pressure side valve body 34 closes the drain port 23, the valve chambers 20 and 21 are communicated with the side wall of the high pressure side valve body 33, and the high pressure fuel in the high pressure side valve chamber 20 is communicated with the low pressure side valve. When the armature 32 flows into the chamber 21 and moves upward by a predetermined amount or more, the communication between the valve chambers 20 and 21 is blocked, and a groove passage 36 is formed so as to prevent the high-pressure fuel from flowing into the low-pressure side valve chamber 21. Has been.

  As a result, high-pressure fuel acts on the high-pressure side valve element 33. Since the high-pressure fuel acts equally on the upper and lower ends of the groove passage 36, the high-pressure side valve element 33 is moved. There is no power to try to make it happen. Therefore, the armature 32 generates a force F4 that is obtained by subtracting a force for pushing the low pressure side valve body 34 upward from a force for lowering the armature 32. This force F4 can be freely determined by adjusting the area where the force of the spring 38 and the high pressure fuel of the low pressure side valve body 34 act. Therefore, the magnetic force Fs generated in the electromagnetic coil 31 can be reduced. As a result, the physique of the electromagnetic coil can be reduced, and as a result, the physique of the three-way electromagnetic valve 30 can be reduced.

Sectional drawing which shows the structure of the fuel-injection apparatus to which the three-way solenoid valve of 1st Embodiment is applied. It is principal part sectional drawing of the three-way solenoid valve in 1st Embodiment of the state which has stopped the electricity supply to an electromagnetic coil. It is principal part sectional drawing of the three-way solenoid valve in 1st Embodiment of the state which has supplied with electricity to the electromagnetic coil. It is principal part sectional drawing of the three-way solenoid valve in 2nd Embodiment. It is radial direction sectional drawing of the armature of the three-way solenoid valve in 2nd Embodiment. It is principal part sectional drawing of the three-way solenoid valve in 3rd Embodiment of the state which has stopped the electricity supply to an electromagnetic coil. It is radial direction sectional drawing of the armature of the three-way solenoid valve in 3rd Embodiment. It is principal part sectional drawing of the three-way solenoid valve in 3rd Embodiment in the state which has supplied with electricity to the electromagnetic coil. It is principal part sectional drawing of the three-way solenoid valve of a prior art.

Explanation of symbols

1 Fuel injection device 10 Body (nozzle body)
11 Inlet 12 Outlet 13 High-pressure fuel passage (high-pressure passage)
14 Drain passage (low pressure passage)
15 Fuel passage (supply passage)
16 Communication passage 17 Injection hole 18 Fuel reservoir chamber 19 Control chamber (supplied chamber)
20 High-pressure side valve chamber (fluid reservoir)
21 Low pressure side valve chamber (fluid reservoir)
22 High-pressure port (high-pressure side opening)
23 Drain port (low-pressure side opening)
24 Control port (supply side opening)
25 Nozzle needle (nozzle valve member)
26 Nozzle seat 27 Orifice 28 Spring 29 Dividing wall 30 Three-way solenoid valve 31 Electromagnetic coil 32 Armature 33 High pressure side valve element (first valve element)
34 Low pressure side valve element (second valve element)
35 Valve body communication path 36 Groove path 37 Guide section 38 Spring 39 Common rail (high pressure source)
40 Pump 41 Fuel tank (low pressure source)

Claims (6)

A three-way solenoid valve that switches the supply of high-pressure fluid from the high-pressure source to the supply chamber and the discharge of high-pressure fluid from the supply chamber to the low-pressure source, and controls the pressure of the supply chamber,
One end is connected to the high pressure source, one end is connected to the low pressure source, the other end is connected to the supply chamber, and the other end is connected to the high pressure passage. A housing formed with a fluid reservoir chamber having a high-pressure side opening, a low-pressure side opening connected to the low-pressure passage, and a supply-side opening connected to the supply passage;
A first valve body that is provided in the fluid reservoir and communicates and blocks the high-pressure passage and the low-pressure passage, and the high-pressure passage and the supply passage;
A second valve body that is provided in the fluid reservoir and moves in a direction substantially perpendicular to an opening surface of the low-pressure side opening to open and close the low-pressure side opening;
An armature that is provided on the opposite side of the low pressure passage of the second valve body and moves the first valve body and the second valve body simultaneously;
The armature is moved by a magnetic force generated by energization, the high pressure passage and the low pressure passage, and the high pressure passage and the supply passage are disconnected by the first valve body, and the second valve body A three-way solenoid valve comprising an electromagnetic coil that opens the low-pressure side opening. The armature is provided between the first valve body and the second valve body,
The first valve body, together with the armature and the second valve body, is moved in a direction substantially perpendicular to the opening surface of the high-pressure side opening, and opens and closes the high-pressure side opening.
When the second valve body closes the low-pressure side opening, the high-pressure fluid from the high-pressure passage acts to cause the second valve body to open the low-pressure side opening. The three-way solenoid valve according to claim 1, further comprising a pressure-receiving surface that generates the force of 2. The three-way solenoid valve according to claim 2,
The fluid reservoir chamber is connected to the high-pressure passage and accommodates the first valve body, and is connected to the low-pressure passage and the supply passage to accommodate the second valve body. A pool room,
The housing is formed with a first communication path that connects the high-pressure fluid reservoir and the low-pressure fluid reservoir,
The outer diameter of the first valve body is smaller than the outer diameter of the second valve body, and the second valve body closes the low-pressure side opening in a state where no magnetic force is generated in the electromagnetic coil. The three-way solenoid valve is characterized in that the outer diameters of the first valve body and the second valve body and the area of the pressure receiving surface of the second valve body are adjusted so as to control the valve. The three-way solenoid valve according to claim 2,
The fluid reservoir chamber is connected to the high-pressure passage and accommodates the first valve body, and is connected to the low-pressure passage and the supply passage to accommodate the second valve body. A pool room,
In each of the first valve body, the second valve body, and the armature, a second communication passage that connects the high-pressure side fluid reservoir chamber and the low-pressure side fluid reservoir chamber is formed,
The outer diameter of the first valve body is smaller than the outer diameter of the second valve body, and the second valve body closes the low-pressure side opening in a state where no magnetic force is generated in the electromagnetic coil. The three-way solenoid valve is characterized in that the outer diameters of the first valve body and the second valve body and the area of the pressure receiving surface of the second valve body are adjusted so as to control the valve. The armature is provided on the anti-low pressure side opening side of the first valve body, and the second valve body is provided on the low pressure side opening side of the first valve body,
The fluid reservoir chamber has a dividing wall that is divided into a high pressure fluid reservoir chamber having the high pressure side opening and a low pressure fluid reservoir chamber having the low pressure side opening and the supply side opening. Formed,
A groove passage is formed in the side wall of the first valve body so that the high-pressure side fluid reservoir chamber and the low-pressure side fluid reservoir chamber can communicate with each other.
The partition wall is penetrated by the first valve body and the second valve body, and supports the first valve body and the second valve body movably in the same direction as the movement direction of the second valve body, When the second valve body closes the low-pressure side opening, the fluid in the high-pressure side fluid reservoir chamber flows into the low-pressure side fluid reservoir chamber via the groove passage, and the armature exceeds a predetermined value. The fluid in the high-pressure side fluid reservoir chamber is formed at a position where the fluid is prevented from flowing into the low-pressure side fluid reservoir chamber via the groove passage when moved. Three-way solenoid valve. A nozzle valve member for opening and closing the nozzle hole;
A nozzle body that supports the nozzle valve member so as to be reciprocally movable, and has a control chamber in which fuel pressure is applied to the nozzle valve member in the direction of closing the nozzle hole;
A fuel injection device comprising: the three-way solenoid valve according to any one of claims 1 to 5, which controls a fuel pressure in the control chamber.

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