JP2002070682A - Fuel injection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop a needle valve substantially in a desired middle lift position without requiring any fine control of fuel feed pressure and switch the fuel injection rate to a desired fuel injection rate. SOLUTION: This fuel injection device comprises the needle valve 2 for opening and closing a nozzle hole 1, a fuel basin chamber 3 for energizing the needle valve 2 to the opening side, a pressure control chamber for energizing the needle valve 2 to the closing side, and a pressure control valve having a spring 5 to control the pressure in the pressure control chamber 4. In the first mode of the pressure control valve 6, the force for energizing the needle valve 2 to the closing side is set larger than the force for energizing it to the opening side in the first mode of the pressure control valve 6. In the second mode of the pressure control valve 6, the force for energizing the needle valve 2 to the closing side is set smaller than the force for energizing it to the opening side to move the needle 2 to the valve opening side. In the third mode of the pressure control valve 6, the pressure control chamber 4 is sealed by the pressure control valve 6, and the needle valve 2 is held by the sealed pressure control chamber 4 and stopped in an optional lift position between full-opening position and full-closing position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a fuel injection device.

[0002]

2. Description of the Related Art Conventionally, an injection hole opening / closing valve for opening / closing a fuel injection injection hole, valve opening side urging means for urging the injection hole opening / closing valve to the valve opening side, and an injection hole opening / closing valve for closing the injection hole opening / closing valve. 2. Description of the Related Art There is known a fuel injection device including a valve-closing-side biasing unit that biases the fuel. As an example of this type of fuel injection device, there is one described in, for example, JP-A-8-334072. JP-A-3-334072
In the fuel injection device described in the publication, the valve-opening-side urging means is formed by a fuel reservoir in the nozzle body, and the valve-closing-side urging means is constituted by a spring.

[0003]

SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open No. 8-
In the fuel injection device described in Japanese Patent No. 334072, the valve-closing-side urging means is constituted by a spring.
In order to move the injection hole opening / closing valve from the fully closed position to the intermediate lift position between the fully open position and the fully closed position, the pressure in the fuel sump chamber is increased, that is, the fuel supply pressure is increased,
The force that urges the nozzle hole opening / closing valve to the valve opening side must be greater than the force that urges the nozzle hole opening / closing valve to the valve closing side. Also, in order to almost stop the injection hole opening / closing valve at the intermediate lift position, the pressure in the fuel reservoir is adjusted, and the force for urging the injection hole opening / closing valve to the valve opening side and the injection hole opening / closing valve to the valve closing side. You must balance the biasing force. In addition, in order to substantially stop the injection hole opening / closing valve at the desired intermediate lift position, the force for urging the injection hole opening / closing valve to the valve opening side at the desired intermediate lift position and the injection hole opening / closing valve are closed. The pressure in the fuel sump chamber must be fine-tuned so that the force acting on the fuel chamber is balanced.

[0004] In view of the above problems, the present invention can move the injection hole opening / closing valve from the fully closed position to the intermediate lift position without increasing the fuel supply pressure, and does not need to finely adjust the fuel supply pressure. It is an object of the present invention to provide a fuel injection device capable of substantially stopping an injection hole opening / closing valve at a desired intermediate lift position, that is, a fuel injection device capable of switching a fuel injection rate waveform to a desired fuel injection rate waveform. .

[0005]

According to the first aspect of the present invention, an injection hole opening / closing valve that opens and closes a fuel injection injection hole, and a valve opening side that urges the injection hole opening / closing valve toward the valve opening side. In a fuel injection device comprising an urging means and a valve closing-side urging means for urging the injection hole opening / closing valve to a valve closing side, the valve closing-side urging means has a pressure control chamber, A pressure control valve for controlling the pressure in the control chamber is disposed in the pressure control valve chamber, and the high-pressure fuel supply passage and the pressure control valve chamber communicate with each other through a first passage,
In the first mode in which the pressure control valve chamber and the pressure control chamber communicate with each other through a second passage, and the pressure control valve is arranged at a first position, fuel flows from the pressure control valve chamber to the low-pressure fuel leak passage. When the flow is interrupted, the fuel in the high-pressure fuel supply passage is supplied to the pressure control chamber through the first passage and the second passage, and the pressure in the pressure control chamber is increased. As a result, The force for urging the nozzle hole opening / closing valve to the valve closing side is greater than the force for urging the nozzle hole opening / closing valve to the valve opening side, and the nozzle hole opening / closing valve is moved toward the fully closed position. In the second mode in which the pressure control valve is disposed at the second position, a flow of fuel from the pressure control chamber to the pressure control valve chamber is allowed, and the low-pressure fuel leak passage extends from the pressure control valve chamber to the low-pressure fuel leak passage. By allowing fuel flow to The fuel in the pressure control chamber is discharged into the low-pressure fuel leak passage through the second passage and the pressure control valve chamber, and the pressure in the pressure control chamber is reduced. The force urging the valve closing side is smaller than the force urging the injection hole opening / closing valve to the valve opening side, and the injection hole opening / closing valve is moved toward the fully open position. In the third mode, the fuel flow between the pressure control chamber and the pressure control valve chamber is shut off to seal the pressure control chamber. A fuel injection device is provided in which the opening / closing valve is held so that the injection hole opening / closing valve is substantially stopped at an arbitrary lift position between the fully open position and the fully closed position.

[0006] In the fuel injection device according to the first aspect, the valve closing-side urging means has a pressure control chamber, and the pressure in the pressure control chamber is controlled by the pressure control valve. Therefore, by disposing the pressure control valve at the first position or the second position and increasing or decreasing the pressure in the pressure control chamber, it is possible to increase or decrease the force for urging the nozzle opening / closing valve toward the valve closing side. Therefore, even if the pressure in the high-pressure fuel supply passage is not increased, the pressure control valve is disposed at the second position, the pressure in the pressure control chamber is reduced, and the injection hole opening / closing valve is urged to the valve closing side. By reducing the force, the injection hole opening / closing valve can be moved from the fully closed position to the intermediate lift position. Further, in the fuel injection device according to the first aspect, when the pressure control valve is disposed at the third position, the pressure control chamber can be sealed by the pressure control valve. Therefore, the injection hole opening / closing valve can be held by the sealed pressure control chamber. Therefore, the injection hole opening / closing valve can be almost stopped at any desired lift position between the fully open position and the fully closed position without finely adjusting the pressure in the high pressure fuel supply passage. In other words, the fuel injection rate waveform can be switched to a desired fuel injection rate waveform by moving the injection hole opening / closing valve to a desired intermediate lift position and substantially stopping there.

According to the second aspect of the invention, in the first mode, the lift amount of the pressure control valve is zero,
In the third mode, the lift amount of the pressure control valve is the maximum value. In the second mode, the lift amount of the pressure control valve is a value between them. When it is required to move to the intermediate lift position, the lift amount of the pressure control valve is increased from zero to start moving the injection hole opening / closing valve, and then the injection hole opening / closing valve is moved to the predetermined intermediate lift position. The pressure control valve lift is fixed to a predetermined value smaller than the maximum value in order to keep moving toward the predetermined position, and then when the injection hole opening / closing valve moves to the predetermined intermediate lift position, the pressure control valve lift is set to the maximum value. The fuel injection device according to claim 1, wherein the fuel injection device is configured to stop the injection hole opening / closing valve substantially at the predetermined intermediate lift position by being fixed.

In the fuel injection device according to the second aspect, when the injection hole opening / closing valve is moved from the fully closed position to the predetermined intermediate lift position, the injection hole opening / closing valve is continuously moved toward the predetermined intermediate lift position. Therefore, the lift amount of the pressure control valve is fixed to a predetermined value smaller than the maximum value. Therefore, while moving the injection hole opening / closing valve from the fully closed position to the predetermined intermediate lift position, the mode is switched from the second mode to the third mode as the pressure control valve lift amount increases to the maximum value. In other words, it is possible to prevent the injection hole opening / closing valve from being stopped, so that the injection hole opening / closing valve cannot be lifted to the predetermined intermediate lift position.

According to the third aspect of the invention, in the first mode, the pressure control valve lift amount is zero,
In the third mode, the lift amount of the pressure control valve is the maximum value. In the second mode, the lift amount of the pressure control valve is a value between them. When it is required to move to the intermediate lift position, the pressure control valve lift amount is increased from zero to start the movement of the injection hole opening / closing valve, and the injection hole opening / closing valve is moved to the predetermined intermediate lift position. Set the rate of increase of the lift of the pressure control valve to a relatively low speed so that the lift of the pressure control valve does not increase to the maximum value before moving.
Then, when the injection hole opening / closing valve moves to the predetermined intermediate lift position, the lift amount of the pressure control valve is fixed to the maximum value, so that the injection hole opening / closing valve is almost stopped at the predetermined intermediate lift position. A fuel injection device according to claim 1 is provided.

In the fuel injection device according to the third aspect, when the injection hole opening / closing valve is moved from the fully closed position to the predetermined intermediate lift position, the pressure is set before the injection hole opening / closing valve moves to the predetermined intermediate lift position. The rate of increase of the lift amount of the pressure control valve is set to a relatively low speed so that the lift amount of the control valve does not increase to the maximum value. Therefore, while moving the injection hole opening and closing valve from the fully closed position to the predetermined intermediate lift position,
As the pressure control valve lift amount increases to the maximum value, the mode is switched from the second mode to the third mode, and the injection hole opening / closing valve is stopped. It is possible to avoid that the lift cannot be performed to the intermediate lift position.

According to the fourth aspect of the present invention, when it is required to move the injection hole opening / closing valve from the fully closed position to a predetermined intermediate lift position, and then to the fully opened position, the pressure control valve lift is required. The pressure control valve lift amount is fixed to a predetermined value smaller than the maximum value in order to start moving the injection hole opening / closing valve by increasing the amount from zero, and then to continue moving the injection hole opening / closing valve toward the fully open position. Then, by fixing the pressure control valve lift amount to the maximum value when the injection hole opening / closing valve moves to the predetermined intermediate lift position, the injection hole opening / closing valve is almost stopped at the predetermined intermediate lift position, Next, the pressure control valve lift is decreased from the maximum value to move the nozzle hole opening / closing valve again toward the fully open position, and then the pressure control is performed to continue moving the nozzle hole opening / closing valve toward the fully open position. Secure the lift amount to a predetermined value greater than zero, the fuel injection device according to claim 2 which is adapted to move the nozzle hole closing valve to the fully open position is provided.

In the fuel injection device according to the fourth aspect, when the injection hole opening / closing valve is moved from the intermediate lift position to the fully open position, the pressure control valve lift amount is set to keep moving the injection hole opening / closing valve toward the full opening position. Is fixed to a predetermined value larger than zero. Therefore, while the injection hole opening / closing valve is being moved from the intermediate lift position to the fully open position, the pressure control valve is switched from the second mode to the first mode as the lift amount decreases to zero, and the injection hole is switched. It can be avoided that the on-off valve starts to move toward the fully closed position, and as a result, the injection hole on-off valve cannot be lifted to the fully open position.

According to the fifth aspect of the present invention, when it is required to move the injection hole opening / closing valve from the fully closed position to a predetermined intermediate lift position and then to the fully opened position, the pressure control valve lift is required. The amount is increased from zero to start the movement of the injection hole opening / closing valve, and the pressure control valve lift amount does not increase to the maximum value before the injection hole opening / closing valve moves to the predetermined intermediate lift position. By setting the increasing speed of the pressure control valve lift amount to a relatively low speed, and then fixing the pressure control valve lift amount to a maximum value when the injection hole opening / closing valve moves to the predetermined intermediate lift position, The injection hole opening / closing valve is substantially stopped at the predetermined intermediate lift position, the lift amount of the pressure control valve is reduced from the maximum value, and the injection hole opening / closing valve is moved again toward the fully open position, Before the on-off valve moves to the fully open position, the pressure control valve lift amount is set to a relatively low speed so that the lift amount of the pressure control valve does not decrease to zero, and the injection hole on-off valve is moved to the fully open position. A fuel injection device according to claim 3, wherein the fuel injection device is moved.

In the fuel injection device according to the fifth aspect, when the injection hole opening / closing valve is moved from the intermediate lift position to the fully opened position, the lift amount of the pressure control valve is reduced to zero before the injection hole opening / closing valve is moved to the fully opened position. The rate of decrease of the lift amount of the pressure control valve is set to a relatively low speed so as not to decrease. Therefore, while the injection hole opening / closing valve is being moved from the intermediate lift position to the fully open position, the pressure control valve is switched from the second mode to the first mode as the lift amount decreases to zero, and the injection hole is switched. It can be avoided that the on-off valve starts to move toward the fully closed position, and as a result, the injection hole on-off valve cannot be lifted to the fully open position.

According to the present invention, the period for fixing the lift amount of the pressure control valve is calculated based on the pressure in the high-pressure fuel supply passage and the fuel temperature. The described fuel injection device is provided.

In the fuel injection device according to the sixth aspect, the pressure in the pressure control chamber that changes according to the lift amount of the pressure control valve further changes according to the pressure in the high-pressure fuel supply passage and the fuel temperature. In view of this, in order to control the pressure in the pressure control chamber as required, the period in which the lift amount of the pressure control valve is fixed is controlled based on the pressure in the high-pressure fuel supply passage and the fuel temperature. Therefore, the pressure in the pressure control chamber can be controlled as required.

According to the seventh aspect of the present invention, the period in which the lift amount of the pressure control valve is fixed is corrected based on the flow rate of the fuel passing through the first passage. Is provided.

In the fuel injection device according to the present invention, the pressure in the pressure control chamber, which changes according to the lift amount of the pressure control valve, further changes according to the fuel flow rate passing through the first passage. In view of this, in order to control the pressure in the pressure control chamber as required, the period during which the lift amount of the pressure control valve is fixed is corrected based on the flow rate of the fuel passing through the first passage. Therefore, the pressure in the pressure control chamber can be controlled as required more accurately than when no correction is performed.

According to the present invention, the increasing speed of the lift amount of the pressure control valve or the decreasing speed of the lift amount of the pressure control valve is calculated based on the pressure in the high-pressure fuel supply passage and the fuel temperature. A fuel injection device according to claim 3 or 5 is provided.

In the fuel injection device according to the present invention, the pressure in the pressure control chamber that changes according to the lift amount of the pressure control valve further changes according to the pressure in the high-pressure fuel supply passage and the fuel temperature. In view of this, in order to control the pressure in the pressure control chamber as required, the increasing speed of the pressure control valve lift or the decreasing speed of the pressure control valve lift is based on the pressure in the high-pressure fuel supply passage and the fuel temperature. Controlled. Therefore, the pressure in the pressure control chamber can be controlled as required.

According to the ninth aspect of the invention, the increasing speed of the pressure control valve lift amount or the decreasing speed of the pressure control valve lift amount is corrected based on the fuel flow rate passing through the first passage. Item 8. A fuel injection device according to item 8 is provided.

In the fuel injection device according to the ninth aspect, the pressure in the pressure control chamber, which changes according to the lift amount of the pressure control valve, further changes according to the fuel flow rate passing through the first passage. In view of the above, in order to control the pressure in the pressure control chamber as required, the increasing speed of the pressure control valve lift amount or the decreasing speed of the pressure control valve lift amount is corrected based on the fuel flow rate passing through the first passage. Therefore, the pressure in the pressure control chamber can be controlled as required more accurately than when no correction is performed.

According to the tenth aspect of the present invention, a lift amount detecting means for detecting a lift amount of the injection hole opening / closing valve is provided, and when the injection hole opening / closing valve is moved to the predetermined intermediate lift position. Based on the difference between the actual injection hole opening / closing valve lift amount and the required injection hole opening / closing valve lift amount, the period during which the pressure control valve lift amount is fixed, the rate of increase of the pressure control valve lift amount, or the pressure control valve lift A fuel injection device according to any one of claims 6 to 9, wherein the rate of decrease of the amount is feedback-corrected.

In the fuel injection device according to the tenth aspect, the actual lift amount of the injection hole opening / closing valve when the injection hole opening / closing valve is moved to the predetermined intermediate lift position, and the required injection hole opening / closing valve lift amount at that time. Based on the difference, the period during which the pressure control valve lift is fixed, the rate at which the pressure control valve lift is increased, or the rate at which the pressure control valve lift is reduced is feedback corrected. Therefore, the injection hole opening / closing valve lift amount can be controlled as required more accurately than when the feedback correction is not performed.

According to the eleventh aspect, the pressure control valve is located at the fourth position where the lift amount of the pressure control valve is smaller than the lift amount of the pressure control valve in the second mode and the third mode. In the fourth mode in which is arranged, the force for urging the injection hole opening / closing valve to the valve closing side and the force for urging the injection hole opening / closing valve to the valve opening side are equal, and the injection hole opening / closing valve is 2. The fuel injection device according to claim 1, wherein the pressure control valve is located at a fourth position when the fuel injection device is located at the fully open position.

In the fuel injection device according to the eleventh aspect, when the injection hole opening / closing valve is located at the fully open position, the lift amount of the pressure control valve is smaller than the lift amount of the pressure control valve in the second mode and the third mode. The pressure control valve is located at a fourth position where the pressure is also smaller. Therefore, compared with the case where the pressure control valve is arranged at the second position or the case where the pressure control valve is arranged at the third position when the injection hole opening / closing valve is located at the fully open position, the fuel is discharged into the low-pressure fuel leak passage. The amount of fuel can be reduced. Therefore, it is possible to suppress the fuel temperature from increasing as the high-pressure fuel is discharged into the low-pressure fuel leak passage.

According to the twelfth aspect of the present invention, a lift amount detecting means for detecting a lift amount of the injection hole opening / closing valve is provided, and when the injection hole opening / closing valve moves to the fully open position, the pressure control valve is immediately turned on. 12. The fuel injection device according to claim 11, wherein the fuel injection device is moved from the second position to the fourth position.

In the fuel injection device according to the twelfth aspect, the pressure control valve is moved from the second position to the fourth position immediately after the injection hole opening / closing valve moves to the fully open position. Therefore, the amount of fuel discharged into the low-pressure fuel leak passage can be minimized.

According to the thirteenth aspect of the present invention, the injection hole opening / closing valve for opening / closing the fuel injection injection hole, valve opening side urging means for urging the injection hole opening / closing valve to the valve opening side, A valve closing side biasing means for biasing the injection hole opening / closing valve to the valve closing side, wherein the valve closing side biasing means has a pressure control chamber,
A pressure control valve for controlling the pressure in the pressure control chamber is provided, and when the pressure control valve is arranged at the first position, a force for urging the nozzle opening / closing valve to the valve closing side is used to open and close the nozzle opening / closing valve. The force for urging the valve toward the valve opening side is greater than the force for urging the nozzle opening / closing valve to the valve closing side when the pressure control valve is disposed at the second position. The injection hole opening / closing valve is moved toward the fully open position by being made smaller than the force for urging the valve opening side, and when the pressure control valve is arranged at the third position, the pressure control chamber is The injection hole opening / closing valve is closed by a pressure control valve, and the injection hole opening / closing valve is held by the sealed pressure control chamber. A fuel injection device adapted to be operated is provided.

In the fuel injection device according to the thirteenth aspect, the valve closing-side urging means has a pressure control chamber, and the pressure in the pressure control chamber is controlled by the pressure control valve. Therefore, by increasing or decreasing the pressure in the pressure control chamber, it is possible to increase or decrease the force for urging the nozzle opening / closing valve toward the valve closing side. therefore,
Even without increasing the fuel supply pressure, by disposing the pressure control valve in the second position, reducing the pressure in the pressure control chamber and reducing the force for urging the nozzle opening / closing valve to the valve closing side, The injection hole opening / closing valve can be moved from the fully closed position to the intermediate lift position. Further, in the fuel injection device according to the thirteenth aspect, when the pressure control valve is disposed at the third position, the pressure control chamber can be sealed by the pressure control valve. Therefore, the injection hole opening / closing valve can be held by the sealed pressure control chamber. Therefore, the injection hole opening / closing valve can be almost stopped at any desired lift position between the fully open position and the fully closed position without finely adjusting the fuel supply pressure. That is, the fuel injection rate can be switched to the desired fuel injection rate by moving the injection hole opening / closing valve to a desired intermediate lift position and substantially stopping there.

According to the present invention, the pressure control valve is controlled based on the pressure in the high pressure fuel supply passage for supplying fuel to the pressure control chamber and the fuel temperature. Item 13. A fuel injection device according to item 13 is provided.

In the fuel injection device according to the present invention, in consideration of the fact that the pressure in the pressure control chamber changes in accordance with the pressure in the high-pressure fuel supply passage and the fuel temperature, the pressure control valve is provided in the high-pressure fuel supply passage. Is controlled based on the pressure and the fuel temperature. Therefore, the pressure in the pressure control chamber can be controlled as required.

[0033]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view of a first embodiment of the fuel injection device of the present invention, and FIG. 2 is an enlarged view of a part of FIG. 1 and 2, reference numeral 1 denotes a fuel injection nozzle,
Reference numeral 2 denotes a needle valve that opens and closes the fuel injection nozzle 1, 3 denotes a fuel reservoir that urges the needle valve 2 to the valve-opening side (upper side in FIGS. 1 and 2), and 4 denotes a needle valve that closes the needle valve 2 (to the valve-closing side). 1 and 2
(Lower side). Reference numeral 5 denotes a spring for urging the needle valve 2 toward the valve closing side (downward in FIGS. 1 and 2), 6 denotes a pressure control valve for controlling the pressure in the pressure control chamber 4, and 7 denotes a pressure control valve. Reference numeral 6 denotes a pressure control valve chamber disposed inside. 8 is a high pressure fuel supply passage, 9 is a first passage connecting the high pressure fuel supply passage 8 and the pressure control valve chamber 7, and 10 is a throttle formed in the first passage 9. 11
Is a second passage connecting the pressure control valve chamber 7 and the pressure control chamber 4, 12 is a throttle formed in the second passage 11, and 13 is a low pressure fuel leak passage. 14 is a piezo-type actuator for driving the pressure control valve 6, and 15 is the pressure control valve 6.
And a piezo-type actuator 14. Specifically, the fuel not injected from the fuel injection nozzle 1 is used as the hydraulic oil 15. Reference numeral 15 denotes a seat portion on which the pressure control valve 6 is seated when fully closed, and reference numeral 16 denotes a spring for urging the pressure control valve 6 toward a valve closing side (upper side in FIGS. 1 and 2).

FIG. 3 shows the first mode and the second mode of the pressure control valve. More specifically, FIG. 3A shows a first mode in which the pressure control valve 6 is disposed in the fully closed position (first position), and FIG. 3B shows that the pressure control valve 6 is in the intermediate lift position. The second mode arranged at (second position) is shown. As shown in FIG. 3A, when the pressure control valve 6 is fully closed (pressure control valve lift amount = 0), the flow of fuel from the pressure control valve chamber 7 to the low-pressure fuel leak passage 13 is shut off. Thereby, the fuel in the high-pressure fuel supply passage 8 is supplied into the pressure control chamber 4 via the first passage 9 and the second passage 11, and the pressure in the pressure control chamber 4 is increased. Therefore, the needle valve 2 is closed (the lower side in FIGS. 1 and 2).
The sum of the oil pressure (fuel pressure) in the pressure control chamber 4 and the spring pressure of the spring 5 urges the needle valve 2 toward the valve opening side (upper side in FIGS. 1 and 2). Therefore, the needle valve 2 is moved to the valve closing side or is maintained at the fully closed position. That is, if the pressure control valve 6 continues to be fully closed, the needle valve 2 is fully closed.

On the other hand, as shown in FIG. 3B, when the pressure control valve 6 is located at the intermediate lift position (second position) (pressure control valve lift amount = L2), the pressure from the pressure control chamber 4 is reduced. By allowing the flow of fuel to the control valve chamber 7 and the flow of fuel from the pressure control valve chamber 7 to the low pressure fuel leak passage 13, the fuel in the pressure control chamber 4 is And low pressure fuel leak passage 1 via pressure control valve chamber 7
The gas is discharged into the pressure control chamber 3 and the pressure in the pressure control chamber 4 is reduced. Therefore, the needle valve 2 is closed (FIGS. 1 and 2).
The sum of the oil pressure (fuel pressure) in the pressure control chamber 4 and the spring pressure of the spring 8 urges the needle valve 2 toward the valve opening side (upper side in FIGS. 1 and 2). The pressure becomes lower than the oil pressure in the fuel pool 3, and as a result, the needle valve 2 is moved to the valve opening side or maintained at the fully open position. That is, when the pressure control valve 6 is maintained at the intermediate lift position, the needle valve 2 is fully opened.

FIG. 4 shows the third mode and the fourth mode of the pressure control valve. Specifically, FIG. 4A shows a third mode in which the pressure control valve 6 is disposed at the fully open position (third position), and FIG. 4B shows a second mode (FIG. 3).
(B) shows a fourth mode in which the pressure control valve 6 is disposed at a fourth position where the pressure control valve lift amount is smaller than the pressure control valve lift amount L2 at the time. As shown in FIG.
When the pressure control valve 6 is fully opened (pressure control valve lift = L3 = Lmax), the pressure control chamber 4 and the pressure control valve chamber 7
And the pressure control chamber 4 is sealed, and the needle valve 2 is closed by the closed pressure control chamber 4.
Is held, the needle valve 2 is almost stopped at an arbitrary lift position between the fully open position and the fully closed position.

As shown in FIG. 4B, when the pressure control valve 6 is located at the fourth position (the pressure control valve lift amount = L
4) The fuel in the high-pressure fuel supply passage 8 is supplied to the pressure control chamber 4 via the first passage 9 and the second passage 11, and the fuel in the pressure control chamber 4 is supplied to the second passage 11 and the pressure control. The fuel is discharged into the low pressure fuel leak passage 13 through the valve chamber 7. Therefore, the sum of the oil pressure (fuel pressure) in the pressure control chamber 4 for urging the needle valve 2 toward the valve closing side (the lower side in FIGS. 1 and 2) and the spring pressure of the spring 8 causes the needle valve 2 to open. It becomes equal to the oil pressure in the fuel sump chamber 3 urged to the valve side (the upper side in FIGS. 1 and 2), and as a result, the needle valve 2 almost stops at any lift position between the fully open position and the fully closed position. I'm sullen.

FIG. 5 is a view showing a pressure control valve control method for executing fuel injection with a low fuel injection rate while maintaining the needle valve at an intermediate lift position between the fully open position and the fully closed position. is there. As shown in FIG. 5, the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount = NLlow) in order to execute fuel injection (fuel injection rate = IRlow) with the fuel injection rate kept low. When the movement is requested (time T1), an increase in the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is increased from zero. When the pressure control valve lift becomes L2 (specifically, when the pressure control valve lift is
4) (time T2), the needle valve 2 starts to move to the valve opening side.

Next, in order to keep moving the needle valve 2 toward a predetermined intermediate lift position (needle valve lift amount = NLlow), the pressure control valve lift amount is fixed at L2 (time T2 to time T3). . Next, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = NL).
When it is necessary to increase the pressure control valve lift amount again to almost stop at low time (time T3), the increase of the voltage applied to the piezoelectric actuator 14 is started again, and the pressure control valve lift amount is again reduced. Increased. The time T3 is set so that the needle valve 2 reaches the predetermined intermediate lift position (needle valve lift = NLlow) when the pressure control valve lift reaches L3 (= Lmax) (time T4). .

Next, when the lift amount of the pressure control valve is L3 (= L
max) (time T4), the needle valve 2 is almost stopped at a predetermined intermediate lift position (needle valve lift amount = NLlow). Also, if the pressure control valve lift amount is L
At 3 (= Lmax) (time T4), the increase in the voltage applied to the piezo actuator 14 is stopped.
Next, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = NLlow) to end the fuel injection.
Is required to be moved to the fully closed position (time T5), the reduction of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is reduced to zero.

FIG. 6 shows a state in which the needle valve is maintained at the intermediate lift position between the fully open position and the fully closed position at the beginning of the fuel injection period to execute the fuel injection with the fuel injection rate kept low. FIG. 5 is a view showing a pressure control valve control method for executing fuel injection with a high fuel injection rate by disposing a needle valve at a fully open position. As shown in FIG. 6, at the beginning of the fuel injection period, the fuel injection rate is kept low (fuel injection rate =
To execute IRlow), the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount = NL).
low) (time T
1) The increase of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is increased from zero. When the lift amount of the pressure control valve becomes L2 (specifically, when the lift amount of the pressure control valve becomes larger than L4)
At (time T2), the needle valve 2 starts to move to the valve opening side.

Next, in order to keep moving the needle valve 2 toward a predetermined intermediate lift position (needle valve lift amount = NLlow), the pressure control valve lift amount is fixed at L2 (time T2 to time T3). . Next, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = NL).
When it is necessary to increase the pressure control valve lift amount again to almost stop at low time (time T3), the increase of the voltage applied to the piezoelectric actuator 14 is started again, and the pressure control valve lift amount is again reduced. Increased. The time T3 is set so that the needle valve 2 reaches the predetermined intermediate lift position (needle valve lift = NLlow) when the pressure control valve lift reaches L3 (= Lmax) (time T4). . Next, when the pressure control valve lift amount reaches L3 (= Lmax) (time T4), the needle valve 2 is almost stopped at a predetermined intermediate lift position (needle valve lift amount = NLlow), and the fuel injection rate is kept low. Fuel injection (fuel injection rate = IRlow) is executed. When the lift amount of the pressure control valve is L3 (= Lma
x) (time T4), the piezo actuator 1
The increase in the applied voltage to 4 is stopped.

Then, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount =
NLlow) to fully open position (needle valve lift = NL)
high) (time T
6) The reduction of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is L3 (= Lma).
x). Pressure control valve lift amount is L2
(In detail, the lift amount of the pressure control valve is L3 (= Lm
ax)) (after time T6), the needle valve 2 starts to move to the valve opening side again.

Next, in order to keep moving the needle valve 2 toward the fully open position (needle valve lift amount = NLhigh), the pressure control valve lift amount is fixed at L2 (time T7 to time T8). When the needle valve 2 abuts on the fully open position (needle valve lift = NLhigh), the fuel injection with a higher fuel injection rate (fuel injection rate = IRhigh)
h) will be executed. Next, when it is required to move the needle valve 2 from the fully open position (needle valve lift amount = NLhigh) to the fully closed position in order to end the fuel injection (time T8), the piezo actuator 1
The reduction of the applied voltage to 4 is started again, and the lift of the pressure control valve is reduced to zero. Next, when the pressure control valve lift amount decreases to zero (time T9), the needle valve 2 starts to move toward the fully closed position. When the needle valve 2 should start moving toward the fully closed position (time T
In time 9), the time T is set so that the lift amount of the pressure control valve becomes zero.
8 is set.

FIG. 7 is a diagram showing a pressure control valve control method for executing fuel injection with a high fuel injection rate from the beginning of the fuel injection period. As shown in FIG. 7, the needle valve 2 is moved from the fully closed position to the fully open position (needle valve lift amount = NLhigh) in order to execute the fuel injection with a high fuel injection rate (fuel injection rate = IRhigh). When requested (time T1), the piezo actuator 14
, The pressure control valve lift amount is increased from zero. When the lift amount of the pressure control valve becomes L2 (specifically, when the lift amount of the pressure control valve becomes larger than L4) (time T2), the needle valve 2 starts to move to the valve opening side.

Next, in order to keep moving the needle valve 2 toward the fully open position (needle valve lift amount = NLhigh), the pressure control valve lift amount is fixed at L2 (time T2 to time T8). When the needle valve 2 abuts on the fully open position (needle valve lift = NLhigh), the fuel injection with a higher fuel injection rate (fuel injection rate = IRhigh)
h) will be executed. Next, when it is required to move the needle valve 2 from the fully open position (needle valve lift amount = NLhigh) to the fully closed position in order to end the fuel injection (time T8), the piezo actuator 1
The reduction of the applied voltage to 4 is started again, and the lift of the pressure control valve is reduced to zero. Next, when the pressure control valve lift amount decreases to zero (time T9), the needle valve 2 starts to move toward the fully closed position. When the needle valve 2 should start moving toward the fully closed position (time T
In time 9), the time T is set so that the lift amount of the pressure control valve becomes zero.
8 is set.

As described above, the pressure control valve lift amount is set to L
2 (time T2 to time T3 in FIG. 5,
6, the fuel flow from the pressure control chamber 4 to the pressure control valve chamber 7 is permitted, and the low-pressure fuel leak passage 13 from the pressure control valve chamber 7 is allowed.
Is allowed to flow to the pressure control chamber 4
The fuel inside is discharged into the low-pressure fuel leak passage 13 through the second passage 11 and the pressure control valve chamber 7, and the pressure in the pressure control chamber 4 is reduced. Therefore, the sum of the oil pressure (fuel pressure) in the pressure control chamber 4 for urging the needle valve 2 toward the valve closing side (the lower side in FIGS. 1 and 2) and the spring pressure of the spring 8 causes the needle valve 2 to open. It becomes smaller than the oil pressure in the fuel sump chamber 3 which urges the valve side (the upper side in FIGS. 1 and 2), and as a result,
The needle valve 2 is moved to the valve opening side.

On the other hand, when the pressure in the high-pressure fuel supply passage 8 is low, the amount of fuel flowing into the pressure control valve chamber 7 through the first passage 9 decreases, so that the pressure control valve chamber 7 As a result, the pressure in the pressure control chamber 4 decreases faster, and the lift speed of the needle valve 2 increases. Further, when the fuel temperature is low, the amount of fuel flowing into the pressure control valve chamber 7 through the first passage 9 decreases as the viscosity of the fuel increases, and the pressure in the pressure control valve chamber 7 decreases. As a result, the pressure in the pressure control chamber 4 decreases rapidly, and the lift speed of the needle valve 2 increases. In the present embodiment, in consideration of these matters, the pressure control valve lift amount is set to L
2 (time T2 to time T3 in FIG. 5, time T2 to time T3, time T7 to time T8 in FIG. 6). Specifically, when the pressure in the high-pressure fuel supply passage 8 is low, the period in which the lift amount of the pressure control valve is fixed to L2 is shortened in consideration of the increase in the lift speed of the needle valve 2. In addition, when the fuel temperature is low, the period during which the lift amount of the pressure control valve is fixed at L2 is shortened in consideration of an increase in the lift speed of the needle valve 2.

Further, when the degree of throttle of the throttle portion 10 of the first passage 9 is stronger than the designed degree of throttle, the amount of fuel flowing into the pressure control valve chamber 7 via the first passage 9 decreases. As a result, the pressure in the pressure control valve chamber 7 decreases rapidly,
As a result, the pressure in the pressure control chamber 4 decreases faster, and the lift speed of the needle valve 2 increases. On the other hand, when the degree of throttle of the throttle portion 10 of the first passage 9 is weaker than the designed degree of throttle, the amount of fuel flowing into the pressure control valve chamber 7 via the first passage 9 increases. As a result, the decrease in the pressure in the pressure control valve chamber 7 is delayed, and as a result, the decrease in the pressure in the pressure control chamber 4 is delayed, and the lift speed of the needle valve 2 decreases. In the present embodiment, in consideration of these matters, the period during which the pressure control valve lift amount is fixed to L2 (time T2 to time T3 in FIG. 5, time T2 to time T3, and time T7 to time T8 in FIG. It is corrected during the evaluation stage of the device. Specifically, when the degree of restriction of the restricting portion 10 of the first passage 9 is stronger than the designed degree of restriction, the lift amount of the needle valve 2 is taken into consideration and the lift amount of the pressure control valve is fixed to L2. The period is shortened. On the other hand, when the degree of restriction of the restricting portion 10 of the first passage 9 is weaker than the designed degree of restriction, the period in which the lift amount of the pressure control valve is fixed to L2 is considered in consideration of the decrease in the lift speed of the needle valve 2. Be lengthened.

In this embodiment, a lift sensor (not shown) for detecting the needle valve lift is provided. When the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = L2) by the lift amount sensor and almost stopped there (time T4 to time T5 in FIG. 5 and time in FIG. 6). The actual needle valve lift amount from T4 to time T6) is detected, and the pressure control valve lift amount is fixed at L2 based on the difference between that value and the required needle valve lift amount (= NLlow) at that time (FIG. 5). , The time T2 to the time T3) in FIG. More specifically, when the detected actual needle valve lift is smaller than the required needle valve lift (= NLlow), the period in which the pressure control valve lift is fixed to L2 (time T2 in FIGS. 5 and 6). ~ Time T3) is lengthened.
On the other hand, when the detected actual needle valve lift is larger than the required needle valve lift (= NLlow), the pressure control valve lift is fixed to L2 (see FIG. 5,
Time T2 to time T3 in FIG. 6 is shortened. This feedback correction may be performed each time the needle valve 2 is moved to the intermediate lift position, or may be periodically performed at predetermined time intervals.

According to the present embodiment, the pressure in the pressure control chamber 4 for urging the needle valve 2 toward the valve closing side (the lower side in FIGS. 1 and 2) is controlled by the pressure control valve 6. Therefore, by disposing the pressure control valve at the first position (FIG. 3A) or the second position (FIG. 3B) and increasing or decreasing the pressure in the pressure control chamber 4, the needle valve 2 is moved. The force urging toward the valve closing side (the lower side in FIGS. 1 and 2) can be increased or decreased. Therefore, even if the pressure in the high-pressure fuel supply passage 8 is not increased, the pressure control valve 6 is disposed at the second position (FIG. 3B), and the pressure in the pressure control chamber 4 is reduced to reduce the pressure. Moving the needle valve 2 from the fully closed position to the intermediate lift position (needle valve lift amount = NLlow) by reducing the force urging the valve 2 toward the valve closing side (the lower side in FIGS. 1 and 2). Can be.

Further, according to the present embodiment, when the pressure control valve is located at the third position (FIG. 4A), the pressure control chamber 4
Can be hermetically closed by the pressure control valve 6. Therefore, the needle valve 2 is closed by the closed pressure control chamber 4.
Can be held. Therefore, the needle valve 2 can be almost stopped at any desired lift position between the fully open position and the fully closed position without finely adjusting the pressure in the high-pressure fuel supply passage 8. That is, the needle valve 2 is moved to a desired intermediate lift position (needle valve lift amount = NLlo).
w) and almost stop there,
The fuel injection rate can be switched to a desired fuel injection rate.

According to the present embodiment, as shown in FIG. 5, when the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount = NLlow), the needle valve 2 In order to continue moving toward the predetermined intermediate lift position, the pressure control valve lift amount is fixed to a predetermined value L2 smaller than the maximum value Lmax (= L3) (time T2 to time T3). For this reason, the needle valve 2 is being moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount = NLlow) (time T1 to time T1).
At time T4), the lift amount of the pressure control valve is increased to the maximum value Lmax.
(= L3), the mode is switched from the second mode (FIG. 3B) to the third mode (FIG. 4A), and the needle valve 2 is stopped. As a result, In addition, it is possible to prevent the needle valve 2 from being unable to lift to the predetermined intermediate lift position (needle valve lift amount = NLlow).

Further, according to the present embodiment, as shown in FIG. 6, when the needle valve 2 is moved from the intermediate lift position (needle valve lift amount = NLlow) to the fully open position (needle valve lift amount = NLhigh), In order to keep moving the needle valve 2 toward the fully open position, the lift amount of the pressure control valve is fixed to a predetermined value L2 larger than zero (time T7 to time T8). Therefore, while the needle valve 2 is being moved from the intermediate lift position (needle valve lift amount = NLlow) to the fully open position (needle valve lift amount = NLhigh) (time T6 to time T9), the pressure control valve lift amount becomes zero. As a result, the mode is switched from the second mode (FIG. 3B) to the first mode (FIG. 3A), and the needle valve 2 starts to move toward the fully closed position. As a result, it is possible to prevent the needle valve 2 from being unable to lift to the fully open position (needle valve lift amount = NLhigh).

Further, according to the present embodiment, the pressure in the pressure control chamber 4 that changes according to the lift amount of the pressure control valve changes further according to the pressure in the high-pressure fuel supply passage 8 and the fuel temperature. In view of this, in order to control the pressure in the pressure control chamber 4 as required, the pressure control valve lift amount is fixed (time T2 to time T3 in FIG. 5, time T2 to time T3, time T7 in FIG. 6). -Time T8) is controlled based on the pressure in the high-pressure fuel supply passage 8 and the fuel temperature. Therefore, the pressure in the pressure control chamber 4 can be controlled as required.

Further, according to the present embodiment, the pressure in the pressure control chamber 4 that changes according to the lift amount of the pressure control valve also changes according to the fuel flow rate passing through the first passage 9. In view of the above, in order to control the pressure in the pressure control chamber 4 as required, the period during which the pressure control valve lift amount is fixed (time T2 to time T3 in FIG. 5, time T2 to time T3 in FIG. 6, time T7 to time T7) T8) is corrected based on the fuel flow rate passing through the first passage 9. Therefore, the pressure in the pressure control chamber 4 can be more accurately controlled as required than when no correction is performed.

Further, according to the present embodiment, the needle valve 2 is set at the predetermined intermediate lift position (needle valve lift amount = NLlo).
w), based on the difference between the actual needle valve lift amount when the needle valve lift amount is moved to the position w) and the required needle valve lift amount NLlow at that time (time T2 to time T3 in FIG. 5; (Time T2 to time T3 in FIG. 6)
Is feedback corrected. Therefore, the needle valve lift amount can be controlled as required more accurately than when the feedback correction is not performed.

Hereinafter, a second embodiment of the fuel injection device of the present invention will be described. The configuration of the present embodiment is the same as the configuration of the above-described first embodiment except for the points described below. Therefore, the same effects as in the first embodiment can be obtained except for the points described below.

FIG. 8 is a diagram showing a pressure control valve control method for executing fuel injection with a low fuel injection rate by maintaining the needle valve at an intermediate lift position between the fully open position and the fully closed position. is there. As shown in FIG. 8, the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount = NLlow) in order to execute fuel injection with the fuel injection rate kept low (fuel injection rate = IRlow). When the movement is requested (time T1), an increase in the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is increased from zero. When the pressure control valve lift becomes L2 (specifically, when the pressure control valve lift is
4), the needle valve 2 starts to move to the valve opening side.

In this case, before the needle valve 2 moves to a predetermined intermediate lift position (needle valve lift amount = NLlow), the lift amount of the pressure control valve is increased to the maximum value Lmax (= L3).
The rate of increase of the pressure control valve lift amount is set to a relatively low speed so as not to increase the time (time T1 to time T4). That is, the rate of increase of the voltage applied to the piezo actuator 14 is set to be relatively low. Specifically, when the lift amount of the pressure control valve reaches L3 (= Lmax) (time T4), the pressure control valve is moved so that the needle valve 2 reaches a predetermined intermediate lift position (needle valve lift amount = NLlow). The increasing speed of the lift amount is set.

Next, when the lift amount of the pressure control valve is L3 (= L
max) (time T4), the needle valve 2 is almost stopped at a predetermined intermediate lift position (needle valve lift amount = NLlow). Also, if the pressure control valve lift amount is L
At 3 (= Lmax) (time T4), the increase in the voltage applied to the piezo actuator 14 is stopped.
Next, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = NLlow) to end the fuel injection.
Is required to be moved to the fully closed position (time T5), the reduction of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is reduced to zero.

FIG. 9 shows a state in which the needle valve is maintained at the intermediate lift position between the fully open position and the fully closed position at the beginning of the fuel injection period to execute the fuel injection with the fuel injection rate kept low. FIG. 5 is a view showing a pressure control valve control method for executing fuel injection with a high fuel injection rate by disposing a needle valve at a fully open position. As shown in FIG. 9, the fuel injection in which the fuel injection rate is kept low at the beginning of the fuel injection period (fuel injection rate =
To execute IRlow), the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount = NL).
low) (time T
1) The increase of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is increased from zero. When the pressure control valve lift amount becomes L2 (specifically, when the pressure control valve lift amount becomes larger than L4),
The needle valve 2 starts to move to the valve opening side.

In this case, before the needle valve 2 moves to the predetermined intermediate lift position (needle valve lift amount = NLlow), the pressure control valve lift amount is increased to the maximum value Lmax (= L3).
The rate of increase of the pressure control valve lift amount is set to a relatively low speed so as not to increase the time (time T1 to time T4). That is, the rate of increase of the voltage applied to the piezo actuator 14 is set to be relatively low. Specifically, when the lift amount of the pressure control valve reaches L3 (= Lmax) (time T4), the pressure control valve is moved so that the needle valve 2 reaches a predetermined intermediate lift position (needle valve lift amount = NLlow). The increasing speed of the lift amount is set. Next, the pressure control valve lift amount is L3 (= Lmax).
(Time T4), the needle valve 2 is almost stopped at a predetermined intermediate lift position (needle valve lift amount = NLlow), and fuel injection (fuel injection rate = IRlow) with a low fuel injection rate is executed. . When the lift amount of the pressure control valve becomes L3 (= Lmax) (time T4), the increase of the voltage applied to the piezo actuator 14 is stopped.

Next, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = fuel injection rate = high) in order to execute fuel injection with a high fuel injection rate (fuel injection rate = IR high).
NLlow) to fully open position (needle valve lift = NL)
high) (time T
6) The reduction of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is L3 (= Lma).
x). Pressure control valve lift amount is L2
(Specifically, when the pressure control valve lift amount becomes smaller than L3 (= Lmax)) (after time T6), the needle valve 2 starts to move to the valve opening side again.

In this case, before the needle valve 2 moves to the fully open position (needle valve lift amount = NLhigh), the reduction speed of the pressure control valve lift amount is compared so that the pressure control valve lift amount does not decrease to zero. It is set to a very low speed (time T6 to time T9). That is, the decreasing speed of the voltage applied to the piezo actuator 14 is set to a relatively low speed. When the needle valve 2 abuts on the fully open position (needle valve lift amount = NLhigh), fuel injection with a high fuel injection rate (fuel injection rate = IRhigh) is executed. Next, when the pressure control valve lift amount decreases to zero (time T9), the needle valve 2 starts to move toward the fully closed position. The reduction rate of the pressure control valve lift amount is set such that the pressure control valve lift amount becomes zero when the needle valve 2 should start moving toward the fully closed position (time T9).

The pressure control valve control method of the present embodiment for executing fuel injection (fuel injection rate = IRhigh) in which the fuel injection rate is increased from the beginning of the fuel injection period is the same as that of the first embodiment shown in FIG. The control valve control method is the same.

As described above, during the period in which the lift amount of the pressure control valve is increased (time T1 to time T1 in FIGS. 8 and 9).
4), and during the period in which the lift amount of the pressure control valve is reduced (time T6 to time T9 in FIG. 9), the flow of fuel from the pressure control chamber 4 to the pressure control valve chamber 7 is allowed, and the pressure control is performed. By allowing the flow of fuel from the valve chamber 7 to the low-pressure fuel leak passage 13, the fuel in the pressure control chamber 4 flows through the second passage 11 and the pressure control valve chamber 7 to the low-pressure fuel leak passage 1.
The gas is discharged into the pressure control chamber 3 and the pressure in the pressure control chamber 4 is reduced. Therefore, the needle valve 2 is closed (FIGS. 1 and 2).
The sum of the oil pressure (fuel pressure) in the pressure control chamber 4 and the spring pressure of the spring 8 urges the needle valve 2 toward the valve opening side (upper side in FIGS. 1 and 2). The pressure becomes lower than the oil pressure in the fuel accumulation chamber 3, and as a result, the needle valve 2 is moved to the valve opening side.

On the other hand, when the pressure in the high-pressure fuel supply passage 8 is low, the amount of fuel flowing into the pressure control valve chamber 7 via the first passage 9 decreases and the pressure control valve chamber 7 As a result, the pressure in the pressure control chamber 4 decreases faster, and the lift speed of the needle valve 2 increases. Further, when the fuel temperature is low, the amount of fuel flowing into the pressure control valve chamber 7 through the first passage 9 decreases as the viscosity of the fuel increases, and the pressure in the pressure control valve chamber 7 decreases. As a result, the pressure in the pressure control chamber 4 decreases rapidly, and the lift speed of the needle valve 2 increases. In the present embodiment, in consideration of these matters, the increasing speed of the pressure control valve lift amount (time T1 to time T4 in FIGS. 8 and 9) and the decreasing speed of the pressure control valve lift amount (time T6 to time T9 in FIG. 9).
Is set. In detail, considering that the lift speed of the needle valve 2 increases when the pressure in the high-pressure fuel supply passage 8 is low, the increasing speed of the lift amount of the pressure control valve (FIGS. 8 and 9)
(Time T1 to time T4) and the reduction speed of the pressure control valve lift amount (time T6 to time T9 in FIG. 9) are set relatively high. Considering that the lift speed of the needle valve 2 increases when the fuel temperature is low, the increase speed of the pressure control valve lift amount (time T1 to time T4 in FIGS. 8 and 9) and the increase of the pressure control valve lift amount are considered. Decrease speed (time T6 to time T in FIG. 9)
9) is set relatively fast.

Further, when the degree of throttle of the throttle portion 10 of the first passage 9 is stronger than the designed degree of throttle, the amount of fuel flowing into the pressure control valve chamber 7 through the first passage 9 decreases. As a result, the pressure in the pressure control valve chamber 7 decreases rapidly,
As a result, the pressure in the pressure control chamber 4 decreases faster, and the lift speed of the needle valve 2 increases. On the other hand, when the degree of throttle of the throttle portion 10 of the first passage 9 is weaker than the designed degree of throttle, the amount of fuel flowing into the pressure control valve chamber 7 via the first passage 9 increases. As a result, the decrease in the pressure in the pressure control valve chamber 7 is delayed, and as a result, the decrease in the pressure in the pressure control chamber 4 is delayed, and the lift speed of the needle valve 2 decreases. In this embodiment, in view of these matters, the increasing speed of the pressure control valve lift amount (time T1 to time T4 in FIGS. 8 and 9) and the decreasing speed of the pressure control valve lift amount (time T6 to time T in FIG. 9).
9) is corrected in the evaluation stage of the fuel injection device. More specifically, when the degree of restriction of the restricting portion 10 of the first passage 9 is stronger than the designed degree of restriction, the rate of increase of the lift amount of the pressure control valve (see FIG. 8, the time T1 to time T4 in FIG. 9 and the decreasing speed of the lift amount of the pressure control valve (time T6 to time T9 in FIG. 9) are corrected to the high speed side. On the other hand, if the degree of restriction of the restricting portion 10 of the first passage 9 is weaker than the designed degree of restriction, the rate of increase of the lift amount of the pressure control valve (FIG. Time T1 to time T in FIG.
4) and the rate of decrease of the lift amount of the pressure control valve (time T in FIG. 9).
6 to T9) is corrected to the low speed side.

In the present embodiment, similarly to the first embodiment, a lift amount sensor (not shown) for detecting a needle valve lift amount is provided. When the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = L2) by the lift amount sensor and almost stopped there (time T4 to time T5 in FIG. 8, FIG. 9).
The actual needle valve lift amount from time T4 to time T6) is detected, and the increasing speed of the pressure control valve lift amount (FIG. 8, The time T1 to time T4 in FIG. 9 and the reduction rate of the lift amount of the pressure control valve (time T6 to time T9 in FIG. 9) are feedback corrected. Specifically, when the detected actual needle valve lift amount is smaller than the required needle valve lift amount (= NLlow), the rate of increase of the pressure control valve lift amount (time T1 to time T in FIGS. 8 and 9).
4) and the rate of decrease of the lift amount of the pressure control valve (time T in FIG. 9).
6 to T9) is corrected to the low speed side. On the other hand, when the detected actual needle valve lift is larger than the required needle valve lift (= NLlow), the rate of increase of the pressure control valve lift (time T1 to time T4 in FIGS. 8 and 9).
And the rate of decrease of the lift amount of the pressure control valve (from time T6 to time T6 in FIG. 9).
Time T9) is corrected to the high-speed side. This feedback correction may be performed each time the needle valve 2 is moved to the intermediate lift position, or may be periodically performed at predetermined time intervals.

According to this embodiment, the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift amount =
NLlow), the pressure control valve lift is increased so that the pressure control valve lift does not increase to the maximum value Lmax (= L3) before the needle valve 2 moves to its predetermined intermediate lift position. The speed is set to a relatively low speed (time T1 to time T4 in FIGS. 8 and 9). Therefore, during the movement of the needle valve 2 from the fully closed position to the predetermined intermediate lift position (needle valve lift amount = NLlow) (time T1 to time T4 in FIGS. 8 and 9), the pressure control valve lift amount With the increase to the maximum value Lmax (= L3), the mode is switched from the second mode (FIG. 3B) to the third mode (FIG. 4A), and the needle valve 2 is stopped. As a result, it is possible to prevent the needle valve 2 from being unable to lift to the predetermined intermediate lift position.

Further, according to the present embodiment, when the needle valve 2 is moved from the intermediate lift position (needle valve lift amount = NLlow) to the fully open position (needle valve lift amount = NLhigh), the needle valve 2 is moved to the fully open position. Before the pressure control valve lift amount is reduced to zero, the rate of decrease of the pressure control valve lift amount is set to a relatively low speed (time T6 to time T9 in FIG. 9). Therefore, the needle valve 2 is moved to the intermediate lift position (needle valve lift amount = N
Llow) to fully open position (needle valve lift = NLh)
during the period from time T6 to time T9 in FIG. 9 (time T6 to time T9 in FIG. 9), the second mode (FIG. 3 (B)) is switched to the first mode as the pressure control valve lift decreases to zero. Switching to (FIG. 3A), the needle valve 2 starts to move toward the fully closed position, and as a result, it is possible to prevent the needle valve 2 from being unable to lift to the fully open position.

Further, according to the present embodiment, the pressure in the pressure control chamber 4 that changes in accordance with the lift amount of the pressure control valve further changes in accordance with the pressure in the high-pressure fuel supply passage 8 and the fuel temperature. In view of the above, in order to control the pressure in the pressure control chamber 4 as required, the increasing speed of the pressure control valve lift amount (time T1 to time T4 in FIGS. 8 and 9) or the decreasing speed of the pressure control valve lift amount (Time T6 to time T9 in FIG. 9) is controlled based on the pressure in the high-pressure fuel supply passage 8 and the fuel temperature. Therefore, the pressure in the pressure control chamber 4 can be controlled as required.

Further, according to the present embodiment, the pressure in the pressure control chamber 4 that changes according to the lift amount of the pressure control valve also changes according to the flow rate of the fuel passing through the first passage 9. In view of this, in order to control the pressure in the pressure control chamber 4 as required, the increasing speed of the lift amount of the pressure control valve (FIGS. 8 and 9)
(Time T1 to time T4) or the decreasing speed of the lift amount of the pressure control valve (time T6 to time T9 in FIG. 9) is corrected based on the fuel flow rate passing through the first passage 9. Therefore, the pressure in the pressure control chamber 4 can be more accurately controlled as required than when no correction is performed.

Further, according to the present embodiment, the actual needle valve at the time when the needle valve 2 is moved to the predetermined intermediate lift position (time T4 to time T5 in FIG. 8 and time T4 to time T6 in FIG. 9). Based on the difference between the lift amount and the required needle valve lift amount NLlow at that time, the pressure control valve lift amount increasing speed (time T1 to time T4 in FIGS. 8 and 9) or the pressure control valve lift amount decreasing speed (FIG. 9, the time T6 to the time T9) are feedback corrected. Therefore, the needle valve lift amount can be controlled as required more accurately than when the feedback correction is not performed.

Hereinafter, a third embodiment of the fuel injection device of the present invention will be described. The configuration of this embodiment is the same as the configurations of the above-described first and second embodiments except for the points described below. Therefore, the same effects as in the first and second embodiments can be obtained except for the points described below. Also in this embodiment, a lift amount sensor (not shown) for detecting the needle valve lift amount is provided.

FIG. 10 shows a state in which the needle valve is maintained at the intermediate lift position between the fully open position and the fully closed position at the beginning of the fuel injection period to execute the fuel injection with the fuel injection rate kept low. FIG. 5 is a view showing a pressure control valve control method for executing fuel injection with a high fuel injection rate by disposing a needle valve at a fully open position. As shown in FIG. 10, the needle valve 2 is moved from the fully closed position to a predetermined intermediate lift position (needle valve lift) in order to execute fuel injection (fuel injection rate = IRlow) in which the fuel injection rate is kept low at the beginning of the fuel injection period. Amount =
NLlow) (time T1), an increase in the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is increased from zero. When the lift amount of the pressure control valve becomes L2 (specifically, when the lift amount of the pressure control valve becomes larger than L4)
At (time T2), the needle valve 2 starts to move to the valve opening side.

Next, in order to keep moving the needle valve 2 toward a predetermined intermediate lift position (needle valve lift amount = NLlow), the pressure control valve lift amount is fixed at L2 (time T2 to time T3). . Next, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount = NL).
When it is necessary to increase the pressure control valve lift amount again to almost stop at low time (time T3), the increase of the voltage applied to the piezoelectric actuator 14 is started again, and the pressure control valve lift amount is again reduced. Increased. The time T3 is set so that the needle valve 2 reaches the predetermined intermediate lift position (needle valve lift = NLlow) when the pressure control valve lift reaches L3 (= Lmax) (time T4). . Next, when the pressure control valve lift amount reaches L3 (= Lmax) (time T4), the needle valve 2 is almost stopped at a predetermined intermediate lift position (needle valve lift amount = NLlow), and the fuel injection rate is kept low. Fuel injection (fuel injection rate = IRlow) is executed. When the lift amount of the pressure control valve is L3 (= Lma
x) (time T4), the piezo actuator 1
The increase in the applied voltage to 4 is stopped.

Then, the needle valve 2 is moved to a predetermined intermediate lift position (needle valve lift amount =
NLlow) to fully open position (needle valve lift = NL)
high) (time T
6) The reduction of the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is L3 (= Lma).
x). Pressure control valve lift amount is L2
(In detail, the lift amount of the pressure control valve is L3 (= Lm
ax)) (after time T6), the needle valve 2 starts to move to the valve opening side again.

Next, in order to keep moving the needle valve 2 toward the fully open position (needle valve lift amount = NLhigh), the pressure control valve lift amount is fixed at L2 (time T7 to time T8 '). When the needle valve 2 abuts on the fully open position (needle valve lift = NLhigh), the fuel injection with a higher fuel injection rate (fuel injection rate = IR
high) will be executed. When the lift sensor detects that the needle valve 2 has reached the fully open position (needle valve lift = NLhigh) (time T8 '), the lift of the pressure control valve is reduced to L4, and the pressure control valve 6 is turned on. It is arranged at a fourth position (FIG. 4B). Next, when it is required to move the needle valve 2 from the fully open position (needle valve lift amount = NLhigh) to the fully closed position in order to end the fuel injection, the voltage applied to the piezo-type actuator 14 is reduced again. , The lift of the pressure control valve is reduced to zero. Next, when the pressure control valve lift amount decreases to zero (time T9), the needle valve 2 starts to move toward the fully closed position. The timing at which the reduction of the voltage applied to the piezo actuator 14 is started again is set so that the pressure control valve lift amount becomes zero when the needle valve 2 should start moving toward the fully closed position (time T9). I have.

FIG. 11 is a diagram showing a pressure control valve control method for executing fuel injection with a high fuel injection rate from the beginning of the fuel injection period. As shown in FIG. 11, the needle valve 2 is moved from the fully closed position to the fully open position (needle valve lift amount = NLhigh) in order to execute the fuel injection with a high fuel injection rate (fuel injection rate = IRhigh). When requested (time T1), an increase in the voltage applied to the piezo actuator 14 is started, and the lift amount of the pressure control valve is increased from zero. When the pressure control valve lift amount becomes L2 (specifically, when the pressure control valve lift amount becomes L4
(Time T2), the needle valve 2 starts to move to the valve opening side.

Next, in order to keep moving the needle valve 2 toward the fully open position (needle valve lift amount = NLhigh), the pressure control valve lift amount is fixed at L2 (time T2 to time T8 "). When the valve 2 hits the fully open position (needle valve lift amount = NLhigh), the fuel injection with a higher fuel injection rate (fuel injection rate = IR
high) will be executed. When the lift amount sensor detects that the needle valve 2 has reached the fully open position (needle valve lift amount = NLhigh) (time T8 ″), the pressure control valve lift amount is reduced to L4, and the pressure control valve 6 is turned on. The needle valve 2 is required to be moved from a fully open position (needle valve lift amount = NLhigh) to a fully closed position in order to terminate fuel injection. Then, the reduction of the voltage applied to the piezo actuator 14 is started again, and the lift of the pressure control valve is reduced to zero, and when the lift of the pressure control valve is reduced to zero (time T9), the needle valve 2 is reset. When the needle valve 2 should start moving toward the fully closed position (time T9), the pressure control valve lift amount becomes zero. In so that the timing for starting the decrease of the voltage applied to the piezoelectric actuator 14 again is set.

According to the present embodiment, when the needle valve 2 is located at the fully open position (needle valve lift = NLhigh) (time T8 'to time T9 in FIG. 10, time T8 "to time T9 in FIG. 11). ), The fourth position (FIG. 3B) in which the pressure control valve lift is smaller than the pressure control valve lift in the second mode (FIG. 3B) and the third mode (FIG. 4A). 4 (B)), the pressure control valve 6 is arranged, so that when the needle valve 2 is located at the fully open position, the pressure control valve is arranged at the second position or at the third position. The fuel amount discharged into the low-pressure fuel leak passage 13 can be reduced as compared with the case where the high-pressure fuel is discharged into the low-pressure fuel leak passage 13. Can be suppressed.

Further, according to the present embodiment, as soon as the needle valve 2 moves to the fully open position (needle valve lift amount = NLhigh), the pressure control valve 6 is moved to the second position (FIG. 3).
(B)) to the fourth position (FIG. 4B) (time T8 'in FIG. 10, time T8 "in FIG. 11).
Therefore, the amount of fuel discharged into the low pressure fuel leak passage 13 can be minimized.

[0086]

According to the first aspect of the present invention, the pressure control valve is disposed at the first position or the second position, and the pressure in the pressure control chamber is increased or decreased to close the injection hole opening / closing valve. The force applied to the valve side can be increased or decreased. Therefore, even if the pressure in the high-pressure fuel supply passage is not increased, the pressure control valve is disposed at the second position, the pressure in the pressure control chamber is reduced, and the injection hole opening / closing valve is urged to the valve closing side. By reducing the force, the injection hole opening / closing valve can be moved from the fully closed position to the intermediate lift position. Further, the injection hole opening / closing valve can be held by the sealed pressure control chamber. Therefore, the injection hole opening / closing valve can be almost stopped at any desired lift position between the fully open position and the fully closed position without finely adjusting the pressure in the high pressure fuel supply passage. That is, the fuel injection rate can be switched to the desired fuel injection rate by moving the injection hole opening / closing valve to a desired intermediate lift position and substantially stopping there.

According to the second aspect of the present invention, the lift amount of the pressure control valve increases to the maximum value while moving the injection hole opening / closing valve from the fully closed position to the predetermined intermediate lift position. As a result, the mode is switched from the second mode to the third mode, and the injection hole opening / closing valve is stopped. As a result,
It is possible to prevent the injection hole opening / closing valve from being unable to lift to the predetermined intermediate lift position.

According to the third aspect of the present invention, the lift amount of the pressure control valve increases to the maximum value while the injection hole opening / closing valve is being moved from the fully closed position to the predetermined intermediate lift position. As a result, the mode is switched from the second mode to the third mode, and the injection hole opening / closing valve is stopped. As a result,
It is possible to prevent the injection hole opening / closing valve from being unable to lift to the predetermined intermediate lift position.

According to the fourth aspect of the invention, while the injection hole opening / closing valve is being moved from the intermediate lift position to the fully open position, the pressure control valve lift amount decreases to zero during the movement. The mode is switched from the second mode to the first mode, and the injection hole opening / closing valve starts to move toward the fully closed position. As a result, it is possible to prevent the injection hole opening / closing valve from being unable to lift to the fully open position.

According to the fifth aspect of the present invention, while the injection hole opening / closing valve is being moved from the intermediate lift position to the fully opened position, the pressure control valve lift amount decreases to zero as the pressure control valve lift amount decreases to zero. The mode is switched from the second mode to the first mode, and the injection hole opening / closing valve starts to move toward the fully closed position. As a result, it is possible to prevent the injection hole opening / closing valve from being unable to lift to the fully open position.

According to the present invention, the pressure in the pressure control chamber can be controlled as required.

According to the seventh aspect of the present invention, the pressure in the pressure control chamber can be controlled as required more accurately than when no correction is performed.

According to the present invention, the pressure in the pressure control chamber can be controlled as required.

According to the ninth aspect, the pressure in the pressure control chamber can be controlled as required more accurately than when no correction is performed.

According to the tenth aspect, the injection hole opening / closing valve lift amount can be controlled as required more accurately than when the feedback correction is not performed.

According to the eleventh aspect, the pressure control valve is located at the second position or the third position when the injection hole opening / closing valve is located at the fully open position. The amount of fuel discharged into the low-pressure fuel leak passage can be reduced as compared with the case of the first embodiment. Therefore, it is possible to suppress the fuel temperature from increasing as the high-pressure fuel is discharged into the low-pressure fuel leak passage.

According to the twelfth aspect, the amount of fuel discharged into the low-pressure fuel leak passage can be minimized.

According to the thirteenth aspect, by increasing or decreasing the pressure in the pressure control chamber, it is possible to increase or decrease the force for urging the nozzle opening / closing valve to the valve closing side. Therefore, even if the fuel supply pressure is not increased, the pressure control valve is disposed at the second position, the pressure in the pressure control chamber is reduced, and the force for urging the nozzle opening / closing valve toward the valve closing side is reduced. By doing
The injection hole opening / closing valve can be moved from the fully closed position to the intermediate lift position. Further, the injection hole opening / closing valve can be held by the sealed pressure control chamber. Therefore, the injection hole opening / closing valve can be almost stopped at any desired lift position between the fully open position and the fully closed position without finely adjusting the fuel supply pressure. That is, the fuel injection rate can be switched to the desired fuel injection rate by moving the injection hole opening / closing valve to a desired intermediate lift position and substantially stopping there.

According to the fourteenth aspect, the pressure in the pressure control chamber can be controlled as required.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a first embodiment of a fuel injection device of the present invention.

FIG. 2 is an enlarged view in which a part of FIG. 1 is enlarged.

FIG. 3 is a diagram showing a first mode and a second mode of the pressure control valve.

FIG. 4 is a diagram showing a third mode and a fourth mode of the pressure control valve.

FIG. 5 shows a pressure control valve control method for executing fuel injection with a low fuel injection rate by maintaining a needle valve at an intermediate lift position between a fully open position and a fully closed position according to the first embodiment. FIG.

FIG. 6 executes fuel injection with the fuel injection rate kept low by maintaining the needle valve at an intermediate lift position between the fully open position and the fully closed position at the beginning of the fuel injection period in the first embodiment;
FIG. 7 is a diagram illustrating a pressure control valve control method for executing fuel injection with a high fuel injection rate by disposing a needle valve at a fully open position during a remaining fuel injection period.

FIG. 7 is a diagram illustrating a pressure control valve control method for executing fuel injection with a high fuel injection rate from the beginning of the fuel injection period in the first embodiment.

FIG. 8 shows a pressure control valve control method for executing fuel injection with a low fuel injection rate by maintaining a needle valve at an intermediate lift position between a fully open position and a fully closed position in the second embodiment. FIG.

FIG. 9 executes fuel injection with the fuel injection rate kept low by maintaining the needle valve at the intermediate lift position between the fully open position and the fully closed position at the beginning of the fuel injection period in the second embodiment;
FIG. 7 is a diagram illustrating a pressure control valve control method for executing fuel injection with a high fuel injection rate by disposing a needle valve at a fully open position during a remaining fuel injection period.

FIG. 10 shows a third embodiment in which the needle valve is maintained at the intermediate lift position between the fully open position and the fully closed position at the beginning of the fuel injection period, and the fuel injection with the fuel injection rate kept low is executed. FIG. 7 is a diagram illustrating a pressure control valve control method for executing fuel injection with a high fuel injection rate by disposing a needle valve at a fully open position during a fuel injection period.

FIG. 11 is a diagram showing a pressure control valve control method for executing fuel injection with a high fuel injection rate from the beginning of the fuel injection period in the third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Injection hole for fuel injection 2 ... Needle valve 3 ... Fuel chamber 4 ... Pressure control chamber 5 ... Spring 6 ... Pressure control valve 7 ... Pressure control valve chamber 8 ... High pressure fuel supply passage 9 ... First passage 10, 12 ... Throttle section 11: second passage 13: low-pressure fuel leak passage 14: piezo actuator 15: hydraulic oil 16: spring

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G066 AA07 AC09 AD07 BA07 BA13 BA51 CC01 CC08T CC14 CC63 CE13 CE27 CE33 CE35 DA16 DC06

Claims (14)

[Claims] 1. An injection hole opening / closing valve for opening / closing a fuel injection injection hole, valve opening side urging means for urging the injection hole opening / closing valve to an opening side, and the injection hole opening / closing valve to a valve closing side. And a valve closing side biasing means for biasing, wherein the valve closing side biasing means has a pressure control chamber and controls a pressure control valve for controlling the pressure in the pressure control chamber. The pressure control valve chamber is disposed in the valve chamber, the high-pressure fuel supply passage and the pressure control valve chamber communicate with each other through a first passage, the pressure control valve chamber and the pressure control chamber communicate with each other through a second passage, and the pressure control valve is connected to the third passage. At the time of the first mode arranged at one position, the flow of fuel from the pressure control valve chamber to the low-pressure fuel leak passage is cut off, so that the fuel in the high-pressure fuel supply passage passes through the first passage and the second passage. The pressure supplied to the pressure control chamber through the passage increases the pressure in the pressure control chamber. As a result, the force urging the nozzle hole opening / closing valve to the valve closing side is greater than the force urging the nozzle hole opening / closing valve to the valve opening side, and the nozzle hole opening / closing valve is moved to the fully closed position. During the second mode in which the pressure control valve is disposed at the second position, the flow of fuel from the pressure control chamber to the pressure control valve chamber is allowed, and By allowing the flow of fuel to the low-pressure fuel leak passage, fuel in the pressure control chamber is discharged into the low-pressure fuel leak passage through the second passage and the pressure control valve chamber, and the pressure control is performed. The pressure in the chamber is reduced, and as a result, the force for urging the nozzle hole opening / closing valve to the valve closing side is smaller than the force for urging the nozzle hole opening / closing valve to the valve opening side, and the nozzle hole opening / closing valve is reduced. Is moved toward the fully open position, and the pressure control valve is moved to the third position. In the third mode, the flow of fuel between the pressure control chamber and the pressure control valve chamber is shut off, the pressure control chamber is closed, and the closed orifice is opened and closed by the closed pressure control chamber. A fuel injection device wherein the injection hole opening / closing valve is substantially stopped at an arbitrary lift position between a fully open position and a fully closed position by holding the valve. 2. The lift amount of the pressure control valve is zero in the first mode, the lift amount of the pressure control valve is the maximum value in the third mode, and the lift amount of the pressure control valve in the second mode. Is the value between them,
When it is required to move the injection hole on / off valve from the fully closed position to a predetermined intermediate lift position, the pressure control valve lift is increased from zero to start moving the injection hole on / off valve, and then the injection The pressure control valve lift amount is fixed to a predetermined value smaller than the maximum value in order to keep moving the hole opening / closing valve toward the predetermined intermediate lift position, and then the injection hole opening / closing valve moves to the predetermined intermediate lift position. 2. The fuel injection device according to claim 1, wherein when the pressure control valve lift is fixed to a maximum value, the injection hole opening / closing valve is substantially stopped at the predetermined intermediate lift position. 3. The lift amount of the pressure control valve is zero in the first mode, the lift amount of the pressure control valve is the maximum value in the third mode, and the lift amount of the pressure control valve in the second mode. Is the value between them,
When it is required to move the injection hole opening / closing valve from the fully closed position to a predetermined intermediate lift position, the lift amount of the pressure control valve is increased from zero to start the movement of the injection hole opening / closing valve, Before the hole opening / closing valve moves to the predetermined intermediate lift position, the rate of increase of the pressure control valve lift is set to a relatively low speed so that the pressure control valve lift does not increase to the maximum value. 2. The injection hole opening / closing valve is substantially stopped at the predetermined intermediate lift position by fixing a pressure control valve lift amount to a maximum value when the hole opening / closing valve moves to the predetermined intermediate lift position. A fuel injection device according to claim 1. 4. When it is required to move the injection hole opening / closing valve from a fully closed position to a predetermined intermediate lift position and then to a fully opened position, the lift amount of the pressure control valve is increased from zero to increase the injection amount. In order to start the movement of the hole opening / closing valve and then to keep moving the injection hole opening / closing valve toward the fully open position, the pressure control valve lift amount is fixed to a predetermined value smaller than the maximum value, and then the injection hole opening / closing valve is By fixing the pressure control valve lift amount to the maximum value when moving to the predetermined intermediate lift position, the injection hole opening / closing valve is almost stopped at the predetermined intermediate lift position, and then the pressure control valve lift amount is set to the maximum value. From the pressure control valve lift amount larger than zero in order to continue moving the injection hole opening / closing valve toward the fully open position, and then continue moving the injection hole opening / closing valve toward the full opening position. 3. The fuel injection device according to claim 2, wherein the injection hole opening / closing valve is moved to a fully open position while being fixed at a constant value. 5. When it is required to move the injection hole opening / closing valve from a fully closed position to a predetermined intermediate lift position and then to a fully opened position, the lift amount of the pressure control valve is increased from zero to increase the injection amount. The movement of the opening / closing valve is started, and the pressure control valve lift is increased so that the pressure control valve lift does not increase to the maximum value before the injection hole opening / closing valve moves to the predetermined intermediate lift position. By setting the speed to a relatively low speed and then fixing the lift amount of the pressure control valve to a maximum value when the injection hole opening / closing valve moves to the predetermined intermediate lift position, the injection hole opening / closing valve is moved to the predetermined intermediate position. The nozzle is almost stopped at the lift position, and then the pressure control valve lift is decreased from the maximum value to move the injection hole opening / closing valve again toward the fully open position, and the injection hole opening / closing valve moves to the fully open position. 4. The pressure control valve lift amount decreasing speed is set to a relatively low speed so that the pressure control valve lift amount is not reduced to zero beforehand, and the injection hole opening / closing valve is moved to a fully open position. A fuel injection device according to claim 1. 6. The fuel injection device according to claim 2, wherein a period during which the lift amount of the pressure control valve is fixed is calculated based on a pressure in the high-pressure fuel supply passage and a fuel temperature. 7. The fuel injection device according to claim 6, wherein a period for fixing the lift amount of the pressure control valve is corrected based on a flow rate of the fuel passing through the first passage. 8. The method according to claim 3, wherein an increasing speed of the pressure control valve lift amount or a decreasing speed of the pressure control valve lift amount is calculated based on a pressure in the high-pressure fuel supply passage and a fuel temperature. Fuel injector. 9. The fuel injection device according to claim 8, wherein an increasing speed of the pressure control valve lift amount or a decreasing speed of the pressure control valve lift amount is corrected based on a fuel flow rate passing through the first passage. 10. A lift amount detecting means for detecting a lift amount of an injection hole opening / closing valve, and an actual injection hole opening / closing valve lift amount when the injection hole opening / closing valve is moved to the predetermined intermediate lift position. Based on the difference between the required lift amount and the required injection hole opening / closing valve lift amount, a feedback correction is performed on the period during which the pressure control valve lift amount is fixed, the increasing speed of the pressure control valve lift amount, or the decreasing speed of the pressure control valve lift amount. The fuel injection device according to any one of claims 6 to 9, wherein: 11. A fourth mode in which the pressure control valve is disposed at a fourth position where the lift amount of the pressure control valve is smaller than the lift amount of the pressure control valve in the second mode and the third mode. The force for urging the injection hole opening / closing valve to the valve closing side and the force for urging the injection hole opening / closing valve to the valve opening side are equal to each other, and when the injection hole opening / closing valve is located at the fully open position, The pressure control valve is arranged at a fourth position.
A fuel injection device according to claim 1. 12. A lift amount detecting means for detecting a lift amount of an injection hole opening / closing valve, wherein the pressure control valve is moved from a second position to a fourth position as soon as the injection hole opening / closing valve moves to a fully open position. The fuel injection device according to claim 11, wherein the fuel injection device is moved to a maximum position. 13. An injection hole opening / closing valve for opening / closing a fuel injection injection hole, valve opening side urging means for urging the injection hole opening / closing valve to a valve opening side, and closing the injection hole opening / closing valve to a valve closing side. A valve closing side biasing means for biasing, the valve closing side biasing means has a pressure control chamber, provided with a pressure control valve for controlling the pressure in the pressure control chamber, When the pressure control valve is disposed at the first position, a force for urging the nozzle hole opening / closing valve toward the valve closing side is greater than a force for urging the nozzle hole opening / closing valve toward the valve opening side, and the pressure When the control valve is located in the second position,
The force that urges the injection hole opening / closing valve toward the valve closing side is made smaller than the force that urges the injection hole opening / closing valve toward the valve opening side, whereby the injection hole opening / closing valve is moved toward the fully open position. ,
When the pressure control valve is disposed at the third position, the pressure control chamber is sealed by the pressure control valve, and the injection hole opening / closing valve is held by the sealed pressure control chamber, whereby the injection hole is closed. A fuel injection device wherein an on-off valve is substantially stopped at an arbitrary lift position between a fully open position and a fully closed position. 14. The fuel injection device according to claim 13, wherein the pressure control valve is controlled based on a pressure in a high-pressure fuel supply passage and a fuel temperature.