JP4716142B2 - Fuel injection device - Google Patents

Description

  The present invention relates to a hydraulically driven fuel injection device.

  Conventionally, a fuel supply system that supplies fuel from a high-pressure pump to an injector as a fuel injection device is known. An injector used in such a system includes a hydraulic drive type that lifts a valve member constituted by a needle valve or the like by fuel pressure. As this type of injector, for example, an injector formed by integrally holding a command piston and a needle valve constituting a valve member is disclosed (for example, see Patent Document 1).

  By the way, in the injector disclosed by patent document 1, the motion of a valve member is controlled by the fuel pressure of the control chamber arrange | positioned on the opposite side to a nozzle hole. Specifically, the control valve is controlled by a control device such as an ECU. When the control valve is opened so as to allow the fuel to be discharged from the control chamber, the fuel pressure in the control chamber decreases. As a result, the valve member moves to the control chamber side, the injection hole is opened, and fuel is injected. On the other hand, when the control valve is closed so as to restrict the discharge of fuel from the control chamber, the fuel pressure in the control chamber increases. As a result, the valve member moves to the injection hole side, the injection hole is closed, and fuel injection is stopped.

JP-A-9-32681

  However, when the injection hole is blocked, it takes a certain amount of time for the fuel pressure in the control chamber to rise after the control valve is closed, so the time until the injection hole is closed becomes longer. There was a problem that. That is, it takes a long time for the valve member to move to a predetermined position after regulating fuel discharge from the control chamber.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a fuel injection capable of shortening the time until the valve member moves to a predetermined position after regulating fuel discharge from the control chamber. To provide an apparatus.

  In the fuel injection device according to the first aspect, the outer structure portion supports the valve member and forms the first control chamber. The first control chamber moves the valve member in the axial direction by the internal fuel pressure. In addition, the plate portion forms a second control chamber that opens to the first control chamber. When the fuel pressure in the first and second control chambers decreases, the valve member comes into contact with the plate portion so as to close the opening.

Further, the fuel injection device includes a supply side throttle channel and a discharge side throttle channel. The supply-side throttle channel is a channel for supplying fuel from the inlet side to the first control chamber via the throttle . On the other hand, the discharge-side throttle channel is a channel for discharging fuel from the second control chamber to the outlet side through the throttle .
Especially in here, in the fuel injection device, higher than the fuel pressure in said first control chamber to the fuel pressure in said second control chamber is supplied to the second control chamber via a throttle fuel from the inlet side A pressure regulating throttle channel that can be maintained is provided. Further, in the state where the valve member is in contact with the plate portion, the flow of fuel from the first control chamber to the second control chamber is blocked, and the fuel from the inlet side passes through the pressure regulating throttle channel only for the second time. It is supplied to the control room.

That is, when the control chamber is configured by the first control chamber and the second control chamber and the fuel pressure in the control chamber is relatively low , the flow of fuel from the first control chamber to the second control chamber is interrupted. It was constructed as that.

Accordingly, when the opening of the second control chamber is closed by the valve member, the fuel pressure in the first control chamber increases. On the other hand, since the fuel is supplied to the second control chamber from the pressure regulation throttle channel, the channel area of the pressure regulation throttle channel is relatively reduced, for example, the channel area of the pressure regulation throttle channel is relatively small. If the area is set appropriately, the fuel pressure in the second control chamber decreases. Then, when regulating the fuel discharged from the second control chamber in this state, the pressure in the second control chamber is increased, the pressure in the first control chamber to remain at a relatively high state. Thereafter, the pressures in the first control chamber and the second control chamber become the same, but the pressure at this time is higher than that in the conventional case. As a result, the fuel pressure required to move the valve member can be reached at a point earlier than before, and the time until the valve member moves to a predetermined position after regulating fuel discharge from the control chamber can be reduced. It can be shortened.

Note that , as shown in claim 2 , the pressure regulation throttle channel may be formed as a communication hole between the fuel passage and the second control chamber inside the plate portion with which the valve member abuts.

Hereinafter, reference embodiments and embodiments of the present invention will be described with reference to the drawings.
The fuel injection system 1 of the first reference type state shown in FIG. 1 is a system for injecting fuel to each cylinder of the internal combustion engine, dimethyl ether as a fuel (Dimethyl. Ether, abbreviated: DME) is injecting DME used System.

  The fuel injection system 1 includes an injector 10 as a “fuel injection device”. In addition to the injector 10, a fuel tank 100, a feed pump 110 as a low-pressure pump, a high-pressure pump 120, a high-pressure common rail 130, electronic control And a device 140 (hereinafter referred to as “ECU”).

  In the fuel tank 100, DME as fuel is stored in a liquid state. It is the feed pump 110 that pumps up this fuel. The feed pump 110 is connected to the high-pressure pump 120, and the fuel pumped up by the feed pump 110 is made high-pressure fuel by the high-pressure pump 120 and accumulated in the high-pressure common rail 130.

  The high-pressure common rail 130 has a supply port 131 and a plurality of (six in this embodiment) discharge ports 132 arranged in the longitudinal direction. A high-pressure pump 120 is connected to the supply port 131, and high-pressure fuel is supplied from the supply port 131 into the high-pressure common rail 130. On the other hand, the injector 10 is connected to each of the plurality of discharge ports 132. Each injector 10 is arranged in each cylinder. Therefore, as many discharge ports 132 as the number of cylinders of the internal combustion engine are provided. In FIG. 1, only one injector 10 is shown, and the rest are omitted.

  Further, the high-pressure common rail 130 has a common rail pressure sensor 133, and information regarding the fuel pressure of the high-pressure common rail 130 is input to the ECU 140. Furthermore, the high pressure common rail 130 has a pressure reducing valve 134. The pressure reducing valve 134 is controlled by the ECU 140 based on information from the common rail pressure sensor 133. In FIG. 1, a control line from the ECU 140 to the pressure reducing valve 134 is not shown in order to avoid complication. Here, when the pressure reducing valve 134 is opened by the ECU 140, a part of the accumulated fuel is returned to the fuel tank 100, and the fuel pressure inside the high-pressure common rail 130 decreases.

  The ECU 140 controls the pressure reducing valve 134 of the high-pressure common rail 130 as described above, and when the internal pressure of the high-pressure common rail 130 becomes a constant pressure, energizes the injector 10 and controls fuel injection by the injector 10.

  As described above, the injector 10 is mounted on each cylinder of the internal combustion engine, and is configured to inject fuel directly into each cylinder. The injector 10 has an inlet 11 and an outlet 12. A discharge port 132 of a high-pressure common rail 130 is connected to the inlet 11, and the outlet 12 is connected to a high-pressure common rail 130 via a back pressure control valve 151 that opens when the pressure becomes equal to or higher than a predetermined pressure (3 MPa in the present embodiment). To the fuel flow path from the fuel tank 100 to the fuel tank 100.

This reference embodiment is characterized by such a structure of the injector 10. Next, the structure of the injector 10 will be described with reference to FIG.
The injector 10 includes a housing 13, a valve body 14, a tip packing 15 interposed between the housing 13 and the valve body 14, and a retaining nut 16 that fastens these members from the outside as members forming the outer shell. It has. The housing 13, the valve body 14, the tip packing 15, and the retaining nut 16 constitute an “outer structure part”.

  The inlet 11 and outlet 12 described above are formed in the housing 13. The fuel supplied from the inlet 11 passes through the passage 17 and then branches. One is guided to the valve body 14 via the passage 18 and is mainly used for injection. The other is used for hydraulic control, which will be described later, via the passage 19.

  A nozzle hole for injecting fuel is provided at the tip of the valve body 14 (not shown in FIG. 2). A passage 20 is formed inside the valve body 14, and a passage 21 is formed inside the tip packing 15. These passages are connected in order of the passage 18, the passage 21, and the passage 20 from the inlet side, whereby the fuel is guided to the tip of the valve body 14. Hereinafter, the side of the valve body 14 is appropriately described as the “tip side” of the injector 10.

  Moreover, the injector 10 is provided with the valve member 22 accommodated in the inside over the longitudinal direction. The valve member 22 includes a needle 23, a coupling portion 24, and a command piston 25 from the distal end side. The needle 23 and the command piston 25 are integrally held by the coupling portion 24.

  Furthermore, the injector 10 includes a solenoid valve portion 30 on the side opposite to the distal end side (hereinafter appropriately described as “base end side”). The electromagnetic valve part 30 is fastened to the housing 13 with a nut 31. The electromagnetic valve unit 30 includes a terminal 32, an armature 33, a body 34, a cup-type stopper 35, a coil 36, a control valve 37 having a T-shape in cross section, and the like.

  The terminal 32 is a terminal for energizing the coil 36. Therefore, a control valve drive current corresponding to the operating condition of the internal combustion engine is supplied to the coil 36 through the terminal 32 by the ECU 140 (see FIG. 1). Then, an excitation attractive force is generated in the coil 36 by supplying the control valve drive current.

  The armature 33 has a cylindrical cup-shaped stopper 35 at the center thereof. The cup-type stopper 35 has a shape that opens to the tip end side, and a spring 38 is disposed therein. The control valve 37 supported by the body 34 is urged by the spring 38. When an exciting suction force is generated in the coil 36 by supplying the control valve driving current, the control valve 37 moves to the proximal end side against the biasing force of the spring 38.

  Various hydraulic control configurations will be described below under the basic configuration as described above.

The hydraulic configuration of the first reference embodiment is as shown in FIG. FIG. 3 is a partially enlarged cross-sectional view of a portion indicated by symbol A in FIG.

  An orifice plate 41 is provided between the control valve 37 and the command piston 25. Although it has already been described that the control valve 37 is biased by the spring 38 (see FIG. 2), the control valve 37 comes into contact with the orifice plate 41 by the biasing force of the spring 38. Specifically, the control valve 37 has a valve 37a at the contact portion. The valve 37a is a part of a sphere configured in a planar shape. The orifice plate 41 is restricted from rotating around the axis by a positioning pin 42. The orifice plate 41 constitutes a “plate portion”.

Next, the configuration of hydraulic control in the injector 10 will be described in more detail.
First, the orifice plate 41 has a recess 43 in the lower part thereof. The base end of the command piston 25 can come into contact with the recess 43.
The vicinity of the base end portion of the command piston 23 is a small diameter portion 25a having a small diameter, and the first control chamber 51 is formed around the small diameter portion 25a. A cylindrical second control chamber 52 is formed in a portion including the central axis of the orifice plate 41. The second control chamber 52 opens into the first control chamber 51 (recess 43).

  Fuel is supplied to the first control chamber 51 via passages 17 and 19 formed in the housing 13 and passages 53 and 54 formed in the orifice plate 41. Here, an in-orifice 55 is formed inside the orifice plate 41, and the two passages 53 and 54 communicate with each other through the in-orifice 55. The in-orifice 55 functions as a supply-side throttle. In this sense, the in-orifice 55 constitutes a “supply side throttle channel”.

  On the other hand, the fuel in the second control chamber 52 is connected to the out orifice 56, the fuel chamber 57 formed in the body 34, and the fuel chamber 57 when the control valve 37 moves to the proximal end side by the excitation suction force of the coil 36. Finally, leakage occurs from the outlet 12 (see FIG. 2) through the passage 58 and the passage 59 connected to the passage 58. On the other hand, when the control valve 37 is in contact with the orifice plate 41 by the biasing force of the spring 38, the out-orifice 56 is closed by the valve 37a and the fuel is not discharged. The out orifice 56 functions as a discharge side throttle. In this sense, the out orifice 56 constitutes a “discharge-side throttle channel”.

  Here, in particular, as shown in FIG. 4A, when the command piston 25 is moved to the distal end side (not lifted), the second control chamber 52 opens into the first control chamber 51 (recess 43). Therefore, the first control room 51 and the second control room 52 function as one control room. That is, in the state where the command piston 25 is not lifted, the pressure regulation throttle channel 61 does not function. FIG. 5A schematically shows this aspect. That is, as shown in FIG. 5A, a path (path indicated by arrow A) of passage 53 → in orifice 55 → control chamber 51, 52 → out orifice 56 → fuel chamber 57 is constructed.

  On the other hand, as shown in FIG. 4B, when the command piston 25 is moved to the proximal end side (lifted state), the proximal end portion of the command piston 25 is an orifice so as to close the opening of the second control chamber 52. It contacts the recess 43 of the plate 41. At this time, the passage 54 and the second control chamber 52 communicate with each other through the pressure regulation throttle channel 61. That is, in the state where the command piston 25 is lifted, the first control chamber 51 and the second control chamber 52 are communicated with each other by the pressure regulating throttle channel 61. This mode is schematically shown in FIG. 5 (b). That is, as shown in FIG. 5B, the path (indicated by arrow B) of passage 53 → in orifice 55 → control chamber 51 → pressure regulation throttle passage 61 → second control chamber 52 → out orifice 56 → fuel chamber 57. Route) is constructed. The pressure regulation throttle channel 61 referred to here constitutes a “pressure regulation throttle channel”.

Next, the operation of the injector 10 will be described. Here, description will be made with reference to FIGS. FIG. 6 is an explanatory diagram showing temporal behavior of each part.
First, when the coil 140 (see FIG. 2) is not energized by the ECU 140, the valve 37a of the control valve 37 is in contact with the orifice plate 41 and closes the out orifice 56.

  In this state, when the coil 140 is energized by the ECU 140 (time t1 in FIG. 6), the valve 37a of the control valve 37 is separated from the orifice plate 41 by the excitation suction force of the coil 36 (see “ (See “Valve Behavior”). Then, the out orifice 56 is opened, and the second control chamber 52 communicates with the low pressure side fuel chamber 57 via the out orifice 56. Here, since the flow passage area of the out orifice 56 is set larger than the in orifice 55, the outflow fuel is larger than the inflow fuel, and the pressure in the first control chamber 51 and the second control chamber 52 is changed from the time t1. It begins to decrease (see “Control Room Pressure Behavior” in FIG. 6).

  When the force toward the distal end acting on the valve member 22 becomes smaller than the force pushing up the valve member 22 (time t2 in FIG. 6), the valve member 22 starts moving toward the proximal end. That is, the valve member 22 begins to lift (see “nozzle lift behavior” in FIG. 5).

  At time t3 in FIG. 6, the valve member 22 is completely opened, and at this time, the command piston 25 closes the opening of the second control chamber 52 as shown in FIG. The base end portion is brought into contact with the concave portion 43 of the orifice plate 41. As a result, as described above, the first control chamber 51 and the second control chamber 52 communicate with each other through the pressure regulation throttle channel 61 (see FIG. 5B). At this time, since the flow of fuel from the first control chamber 51 to the second control chamber 52 is restricted, a pressure difference is generated between the first control chamber 51 and the second control chamber 52. Specifically, the fuel pressure in the first control chamber 51 is larger than the fuel pressure in the conventional control chamber, and the fuel pressure in the second control chamber 52 is smaller than the fuel pressure in the conventional control chamber.

  Next, when the drive current supply from the ECU 140 to the coil 36 is completed at time t4 in FIG. 6, the valve 37a of the control valve 37 again comes into contact with the orifice plate 41 by the biasing force of the spring 38. As a result, in the second control chamber 52, the fuel pressure rises as the out orifice 56 is closed. At time t5, the pressures in the first control chamber 51 and the second control chamber 52 are the same. However, since the fuel pressure in the first control chamber 51 changes in a relatively high state by the pressure regulation throttle passage 61, the pressures in the first and second control chambers 51 and 52 are higher than in the conventional case at this time t5. Become.

  In the conventional configuration, after the valve 37a of the control valve 37 again comes into contact with the orifice plate 41 by the urging force of the spring 38 at time t4, the pressure in the control chamber does not rapidly increase. At time t7, the valve member 22 starts moving toward the tip side, and at time t9, the nozzle hole is closed. On the other hand, in the present embodiment, the fuel pressure at time t5 is larger than that in the conventional case, so that the valve member 22 starts moving toward the tip side from time t6 (time earlier than time t7), and time t8 ( The nozzle hole is closed at a time earlier than time t9). That is, conventionally, the time from the end time (time t4) of the supply of drive current to the coil 36 from the ECU 140 to the time t9 is the “valve closing time”, whereas in the present embodiment, the time from the time t4 to the time t8. The time until is the “valve closing time”.

  As described above in detail, in the present embodiment, the first control chamber 51 and the second control chamber 52 constitute a control chamber, and in a state where the fuel pressure in the control chamber is relatively low, the pressure regulation throttle channel 61 Thus, the first control chamber 51 and the second control chamber 52 are configured to communicate with each other. As a result, the flow of fuel from the first control chamber 51 to the second control chamber 52 is restricted, so that a pressure difference is generated between the first control chamber 51 and the second control chamber 52. Here, when the valve 37a of the control valve 37 again comes into contact with the orifice plate 41, the pressures in the first control chamber 51 and the second control chamber 52 become the same at time t5, but the fuel pressure in the first control chamber 51 becomes the same. Since the pressure regulation throttle passage 61 makes a transition to a relatively high state, the pressure in the first and second control chambers 51 and 52 becomes higher than that at the time at time t5. Therefore, the time from when the out orifice 56 is closed until the valve member moves to a predetermined position (valve closing position) can be shortened (see FIG. 6).

  Note that the pressure regulation throttle channel 61 described above is formed by the base end portion of the command piston 25 coming into contact with the orifice plate 41. In this sense, “the pressure regulation throttle channel is formed in the contact portion of the plate portion with which the valve member abuts”.

The hydraulic configuration of the second reference form is as shown in FIG. FIG. 7 is a partial enlarged cross-sectional view showing the configuration of the injector 90.

  As shown in FIG. 7, the base end portion of the command piston 250 is a small diameter portion 250a having a relatively small diameter. Thus, a first control chamber 510 is formed around the small diameter portion 250a of the command piston 250. A cylindrical second control chamber 520 is formed in a portion including the central axis of the orifice plate 410. The orifice plate 410 forms a “plate portion”.

  Fuel is supplied to the first control chamber 510 via passages 17 and 19 formed in the housing 13 and a passage 530 formed in the orifice plate 410. Here, an in-orifice 550 is formed inside the orifice plate 410, and the passage 530 and the first control chamber 510 communicate with each other through the in-orifice 550. The in-orifice 550 functions as a supply-side throttle. In this sense, the in-orifice 550 constitutes a “supply side throttle channel”.

  On the other hand, when the control valve 37 moves upward, the fuel in the second control chamber 520 is connected to the out orifice 560, the fuel chamber 57 formed in the body 34, the passage 58 connected to the fuel chamber 57, and the passage 58. Leaked via the passage 59. On the other hand, when the control valve 37 is in contact with the orifice plate 410, the out-orifice 560 is closed by the valve 37a, and fuel is not discharged. The out orifice 560 functions as a discharge side restriction. In this sense, the out orifice 560 constitutes a “discharge-side throttle channel”.

  Here, in particular, as shown in FIG. 7A, when the command piston 250 is moved to the proximal end side (lifted state), the first control chamber 510 and the second control chamber 520 are connected to the pressure regulation throttle channel 610. Communicating at As shown in FIG. 7B, the pressure regulation throttle channel 610 is formed by a radial narrow groove formed on the base end surface of the command piston 250. On the other hand, in a state where the command piston 250 moves to the tip side (a state where the command piston 250 is not lifted), the first control chamber 510 and the second control chamber 520 function as one control chamber. That is, in the state where the command piston 250 is not lifted, the pressure regulation throttle channel 610 does not function. In this case, the same fuel path as shown in FIG. 5 is formed.

Even with such a configuration, the same effect as the above-described reference embodiment can be obtained. The pressure regulating throttle channel 610 described above is formed by the orifice plate 410 and a narrow groove on the base end face of the command piston 250. That is, “the pressure regulation throttle channel is formed by the plate portion and the concave portion of the base end surface of the valve member”.

The hydraulic configuration of the third reference embodiment is as shown in FIG. FIG. 8A is a partial enlarged cross-sectional view showing the configuration of the injector 91.

  As shown in FIG. 8A, the base end portion of the command piston 251 is a small diameter portion 251a having a relatively small diameter. Thus, a first control chamber 511 is formed around the small diameter portion 251a of the command piston 251. A cylindrical second control chamber 520 is formed in a portion including the central axis of the orifice plate 410. The configuration of the orifice plate 410 is the same as that described above, and thus the same reference numerals are given. Similarly, the orifice plate 410 forms a “plate portion”.

  Fuel is supplied to the first control chamber 511 through passages 17 and 19 formed in the housing 13 and a passage 530 formed in the orifice plate 410. Here, an in-orifice 550 is formed in the orifice plate 410, and the passage 530 and the first control chamber 511 communicate with each other through the in-orifice 550. The in-orifice 550 functions as a supply-side throttle. In this sense, the in-orifice 550 constitutes a “supply side throttle channel”.

  On the other hand, when the control valve 37 moves to the proximal end side, the fuel in the second control chamber 520 flows into the out orifice 560, the fuel chamber 57 formed in the body 34, the passage 58 connected to the fuel chamber 57, and the passage 58. It leaks via the connected passage 59. On the other hand, when the control valve 37 is in contact with the orifice plate 410, the out-orifice 560 is closed by the valve 37a, and fuel is not discharged. The out orifice 560 functions as a discharge side restriction. In this sense, the out orifice 560 constitutes a “discharge-side throttle channel”.

  Here, in particular, as shown in FIG. 8A, in the state where the command piston 251 is moved to the base end side (the lifted state), the first control chamber 511 and the second control chamber 520 are connected to the pressure regulating throttle channel 611. Communicating at As shown in FIG. 8B, the pressure regulation throttle channel 611 is formed in the base end portion of the command piston 250 as a through hole inclined from the center of the base end surface. On the other hand, in a state where the command piston 251 moves to the tip side (a state where the command piston 251 is not lifted), the first control chamber 511 and the second control chamber 520 function as one control chamber. That is, in the state where the command piston 251 is not lifted, the pressure regulation throttle channel 611 does not function. In this case, the same fuel path as shown in FIG. 5 is formed.

Even with such a configuration, the same effect as the above-described reference embodiment can be obtained. Note that the pressure regulation throttle channel 611 described above is formed as a through hole in the base end portion of the command piston 251. In other words, “the pressure regulation throttle flow path is formed as a through hole in the base end portion of the valve member in contact with the plate portion”.

The hydraulic configuration of one embodiment of the present invention is as shown in FIG. FIG. 9 is a partially enlarged cross-sectional view showing the configuration of the injector 92.

  As shown in FIG. 9, the base end portion of the command piston 252 is a small diameter portion 252a having a relatively small diameter. Thus, a first control chamber 512 is formed around the small diameter portion 252a of the command piston 252. A cylindrical second control chamber 522 is formed at a portion including the central axis of the orifice plate 412. The orifice plate 412 constitutes a “plate portion”.

  Fuel is supplied to the first control chamber 512 via passages 17 and 19 formed in the housing 13 and a passage 532 formed in the orifice plate 412. Here, an in-orifice 552 is formed in the orifice plate 412, and the passage 532 and the first control chamber 512 communicate with each other through the in-orifice 552. The in-orifice 552 functions as a supply-side throttle. In this sense, the in-orifice 552 constitutes a “supply side throttle channel”. Further, a pressure regulation throttle channel 612 is formed inside the orifice plate 412, and the passage 532 and the second control chamber 522 communicate with each other through the pressure regulation throttle channel 612. The pressure regulation throttle channel 612 constitutes a “pressure regulation throttle channel”.

  On the other hand, when the control valve 37 moves to the proximal end side, the fuel in the second control chamber 522 flows into the out orifice 562, the fuel chamber 57 formed in the body 34, the passage 58 connected to the fuel chamber 57, and the passage 58. It leaks via the connected passage 59. On the other hand, when the control valve 37 is in contact with the orifice plate 412, the out-orifice 562 is closed by the valve 37a, and fuel is not discharged. The out orifice 562 functions as a discharge side restriction. In this sense, the out orifice 562 forms a “discharge-side throttle channel”.

  Here, in a state where the command piston 252 is moved to the tip side (a state where the command piston 252 is not lifted), the second control chamber 522 is open to the first control chamber 512, and therefore, the first control chamber 512 and the second control chamber. 522 functions as one control room. FIG. 10A schematically shows this aspect. That is, as shown in FIG. 10 (a), a path 532 → in orifice 552 and pressure regulating throttle channel 612 → control chamber 512, 522 → out orifice 562 → fuel chamber 57 (paths indicated by arrows C and D). Is built.

  On the other hand, in a state where the command piston 25 has moved to the base end side (a lifted state), the base end portion of the command piston 252 contacts the orifice plate 412 so as to close the opening of the second control chamber 522. At this time, the first control chamber 512 and the second control chamber 522 are disconnected, and fuel is supplied to the second control chamber from the pressure regulating throttle channel 612. FIG. 10B schematically shows this aspect. That is, as shown in FIG. 10B, the path 532 → the in-orifice 552 → the first control chamber 512 (the path indicated by the arrow F), and the path 532 → the pressure regulating throttle channel 612 → the second control chamber 522. A route (route indicated by arrow E) of → out orifice 562 → fuel chamber 57 is established.

Even with such a configuration, the same effect as the above-described reference embodiment can be obtained. The pressure regulation flow path 611 described above is a communication hole inside the orifice plate 412 with which the command piston 252 contacts. That is, “the pressure regulation throttle flow path is formed as a communication hole between the fuel passage and the second control chamber inside the plate portion with which the valve member abuts”.

  As mentioned above, this invention is not limited to the said embodiment, In the range which does not deviate from the meaning of invention, it can implement with a various form.

It is a schematic block diagram which shows the fuel-injection system of the various forms of this invention. It is a schematic block diagram which shows the fuel-injection apparatus of the various forms of this invention. It is a partial expanded sectional view which shows the characteristic structure of an injector. It is explanatory drawing for demonstrating the characteristic part of an injector. It is explanatory drawing which shows the fuel path | route constructed | assembled by the position of a valve member. It is explanatory drawing which shows the time behavior of a fuel-injection apparatus. It is a partial expanded sectional view which shows the characteristic structure of an injector. It is a partial expanded sectional view which shows the characteristic structure of an injector. It is a partial expanded sectional view which shows the characteristic structure of the injector of one Embodiment of this invention. It is explanatory drawing which shows the fuel path | route constructed | assembled by the position of a valve member.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Fuel injection system 10, 90, 91, 92 ... Injector (fuel injection apparatus), 11 ... Inlet, 12 ... Outlet, 13 ... Housing, 14 ... Valve body, 15 ... Tip packing, 16 ... Retaining nut, 17 -21 ... passage, 22 ... valve member, 23 ... needle, 24 ... coupling part, 25, 250, 251, 252 ... command piston, 25a, 250a, 251a, 252a ... small diameter part, 30 ... solenoid valve part, 31 ... Nut, 32 ... terminal, 33 ... armature, 34 ... body, 35 ... cup-type stopper, 36 ... coil, 37 ... control valve, 37a ... valve, 38 ... spring, 41, 410, 412 ... orifice plate (plate part), 42 ... Pin, 43 ... Recess, 51, 510, 511, 512 ... First control chamber, 52, 520, 522 ... First Control chamber, 53, 54, 530, 532 ... passage, 55, 550, 552 ... in-orifice (supply side throttle channel), 56, 560, 562 ... out orifice (discharge side throttle channel), 57 ... fuel chamber, 58, 59 ... passage, 61, 610, 611, 612 ... pressure regulating throttle channel (pressure regulating throttle channel), 100 ... fuel tank, 110 ... feed pump, 120 ... high pressure pump, 130 ... high pressure common rail, 131 ... supply , 132 ... discharge port, 133 ... common rail pressure sensor, 134 ... pressure reducing valve, 151 ... back pressure control valve

Claims (2)

A valve member supported so as to be movable in the axial direction;
An outer shell forming a first control chamber on the base end side of the valve member for supporting the valve member and moving the valve member in an axial direction by an internal fuel pressure;
Forming a second control chamber that opens in the first control chamber, and a plate portion with which the valve member abuts so as to close the opening when the fuel pressure in the first and second control chambers decreases;
A supply-side throttle channel for supplying fuel from the inlet side to the first control chamber via a throttle;
A pressure regulating throttle flow capable of supplying fuel from the inlet side to the second control chamber via a throttle and maintaining the fuel pressure in the first control chamber higher than the fuel pressure in the second control chamber. Road,
A discharge side throttle passage for discharging fuel from the second control chamber to the outlet side through the throttle;
Equipped with a,
In a state where the valve member is in contact with the plate portion, the flow of fuel from the first control chamber to the second control chamber is interrupted, and fuel from the inlet side passes only through the pressure regulating throttle channel. A fuel injection device supplied to the second control chamber . The fuel injection device according to claim 1 ,
The fuel injection device according to claim 1, wherein the pressure regulation throttle flow path is formed as a communication hole between a fuel passage inside the plate portion in contact with the valve member and the second control chamber.

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