JP3539294B2 - Fuel injection valve for internal combustion engine - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fuel injection valve for an internal combustion engine.
[0002]
[Prior art]
Conventionally, an armature, a valve-opening drive solenoid in which a valve-opening drive current is supplied to drive the armature to open, and a valve-closing drive in which a valve-opening drive current is supplied to close the armature A fuel injection valve for an internal combustion engine including a solenoid is known. As an example of this type of fuel injection valve for an internal combustion engine, there is one described in FIG. 12 of JP-A-7-239050.
[0003]
[Problems to be solved by the invention]
However, Japanese Patent Application Laid-Open No. 7-239050 discloses that the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the direction of the armature axis and in the steady state when the valve-opening drive current is supplied, It is disclosed that the direction of the valve-closing drive current flowing through the coil of the valve drive solenoid with respect to the armature axis direction is arranged such that it is in the same direction as that in the steady state when the valve-closing drive current is supplied. Absent. Therefore, in the fuel injection valve for an internal combustion engine described in JP-A-7-239050, the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the armature axis direction, The direction of the valve-closing drive current flowing through the coil of the valve-closing drive solenoid with respect to the direction of the armature axis in the steady state at the time is the same as that in the steady state when the valve-closing drive current is supplied. And the induced electromotive force generated during the transition after the energization of the valve-closing drive solenoid is started promotes demagnetization of the magnetic attraction force remaining in the valve-opening drive solenoid after energization of the valve-opening drive solenoid I can't let it go.
[0004]
Japanese Patent Application Laid-Open No. Hei 7-198053 discloses an electromagnetic control provided with a degaussing solenoid for promoting degaussing of a magnetic attraction force remaining in the valve opening driving solenoid after the energization of the valve opening driving solenoid. A valve is disclosed.
[0005]
However, in the electromagnetic control valve described in Japanese Patent Application Laid-Open No. 7-198053, the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the armature axis direction and the steady state when the valve-opening drive current is supplied It is arranged so that the direction in the state and the direction of the demagnetizing current flowing through the coil of the degaussing solenoid with respect to the direction of the armature axis in the steady state when the demagnetizing current flows are opposite to each other. Therefore, in the electromagnetic control valve described in Japanese Patent Application Laid-Open No. 7-198053, the induced electromotive force generated during the transition after the energization of the demagnetizing solenoid is started causes the solenoid to be opened and closed after the energization of the solenoid for opening and closing is completed. The demagnetization of the magnetic attraction force remaining thereafter cannot be promoted.
[0006]
Furthermore, in the electromagnetic control valve described in Japanese Patent Application Laid-Open No. 7-198053, although the solenoid for valve opening drive is arranged at one end in the longitudinal direction of the armature, the solenoid for degaussing is arranged at the other end in the longitudinal direction of the armature. It is arranged at one end in the longitudinal direction of the armature similarly to the solenoid for valve-opening drive. Therefore, in the electromagnetic control valve described in Japanese Patent Application Laid-Open No. 7-198053, although the armature can be driven to be opened by the valve-opening solenoid, the armature cannot be driven to be closed by the demagnetizing solenoid.
[0007]
In view of the above problems, the present invention provides a valve opening drive by a valve opening drive solenoid and a valve closing drive by a valve closing drive solenoid, and an induced electromotive force generated during a transient after the start of energization to the valve closing drive solenoid. Accordingly, the present invention provides a fuel injection valve for an internal combustion engine capable of promoting demagnetization of a magnetic attraction force remaining in the valve-opening drive solenoid after energization of the valve-opening drive solenoid and improving valve-closing responsiveness. The purpose is to:
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, an armature, a valve-opening drive solenoid to which a valve-opening drive current is supplied to open and drive the armature, and a valve-closed valve to close-drive the armature A fuel injection valve for an internal combustion engine including a valve-closing drive solenoid to which a drive current is supplied, wherein the valve-opening drive current flowing through the coil of the valve-opening drive solenoid is oriented in the direction of the armature axis, and the valve is opened. The one in the steady state when the drive current is supplied and the one in the steady state when the valve closing drive current flowing through the coil of the valve closing drive solenoid is in the direction of the armature axis and the valve closing drive current is supplied. In the same directionThe demagnetization of the magnetism generated by the other solenoid is promoted by the induced electromotive force generated by the current flowing through the coil of one solenoid in the transient state.A fuel injector for an internal combustion engine is provided.
[0009]
In the fuel injection valve for an internal combustion engine according to the first aspect of the present invention, the armature can be driven to open by energizing the valve-opening drive solenoid with the valve-opening drive current, and the valve-closed drive solenoid is closed. When the driving current is supplied, the armature can be driven to close the valve. Further, the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the armature axis direction in a steady state when the valve-opening drive current is applied, and the valve closing of the valve-closing drive solenoid flowing through the coil of the valve-opening drive solenoid It is arranged so that the direction of the drive current with respect to the armature axis direction is the same as that in the steady state when the valve-closing drive current is supplied.The demagnetization of the magnetism generated by the other solenoid is promoted by the induced electromotive force generated by the current flowing through the coil of one solenoid in the transient state.. Therefore, when the start of energization of one solenoid and the end of energization of the other solenoid are performed at about the same time, an induction current that occurs in a transient state in the current flowing through the coil of the energized solenoid. The direction of the electric power is opposite to the direction of the induced electromotive force generated in the transient state, which is the current flowing through the coil of the solenoid that has been de-energized, and the respective induced electromotive forces cancel each other. . In other words, the demagnetization of the magnetism generated by the other solenoid can be promoted by the induced electromotive force generated by the current flowing through the solenoid coil that has been energized and in the transient state. That is, a current flowing through a coil of a solenoid that has been energized and a magnetic flux generated in a steady state demagnetizes the magnetism generated by the other solenoid, as described in JP-A-7-198053. In contrast, the magnetism generated by the other solenoid can be demagnetized during the transition of the current flowing through the solenoid coil when energization is started. Therefore, for example, when the start of energization of the valve-closing drive solenoid and the end of energization of the valve-opening drive solenoid are performed at substantially the same time, the armature axis of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid is used. Direction in the steady state when the valve-opening drive current is applied, and when the valve-closing drive current flowing through the coil of the valve-close drive solenoid is in the direction of the armature axis and the valve-opening drive current is applied. The valve closing responsiveness can be improved as compared with the case where the device is not arranged in the same direction as that in the steady state.
[0010]
According to the second aspect of the present invention, the armature is formed of a single armature, the valve-opening drive solenoid is disposed at one longitudinal end of the armature, and the valve-closing drive solenoid is provided in the longitudinal direction of the armature. Placed at the other end in the directionThe induced electromotive force generated during the transient after the energization of the valve-closing drive solenoid is started promotes the demagnetization of the magnetic attraction force remaining in the valve-opening drive solenoid after the energization of the valve-opening drive solenoid. BeA fuel injection valve for an internal combustion engine according to claim 1 is provided.
[0011]
In the fuel injection valve for an internal combustion engine according to the second aspect, the valve opening drive solenoid is disposed at one longitudinal end of the armature and the valve closing drive solenoid is disposed at the other longitudinal end of the armature. The valve opening drive by the drive solenoid and the valve closing drive by the valve closing drive solenoid can be reliably performed.In addition, the induced electromotive force generated during a transition after the energization of the valve-closing drive solenoid is started can promote demagnetization of the magnetic attraction force remaining in the valve-opening drive solenoid after the energization of the valve-opening drive solenoid is completed. The direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the armature axis direction in the steady state when the valve-opening drive current is applied, and the valve closing through the valve-opening drive solenoid coil The direction of the drive current with respect to the armature axis direction is the same as that in the steady state when the valve-closing drive current is supplied. Therefore, unlike magnetic flux generated in the steady state after the start of energization of the valve-opening drive solenoid, the magnetic attraction force remaining in the other solenoid is demagnetized. It is possible to demagnetize the magnetic attraction force remaining in the valve opening drive solenoid.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0017]
FIG. 1 is a partial sectional side view of an embodiment of the fuel injection valve for an internal combustion engine of the present invention. In FIG. 1, reference numeral 1 denotes an armature, 2 denotes a valve-opening drive solenoid through which a valve-opening drive current is applied to open and drive the armature 1, and 3 denotes a valve-closing drive current to drive the armature 1 to close. Is a solenoid for valve closing drive to be energized. Reference numeral 4 denotes an injection hole, 5 denotes a valve body connected to the armature 1 for opening and closing the injection hole 4, 6 denotes a main body pipe, 7 denotes a magnetic path formed by a valve opening drive solenoid 2 or a valve closing drive solenoid 3. Is a magnetic path constituting member constituting a part of the magnetic path. Numeral 8 denotes a non-magnetic member arranged to prevent a magnetic path formed by the valve-opening drive solenoid 2 and a magnetic path formed by the valve-closing drive solenoid 3 from overlapping each other, and 9 denotes a fuel. The passage 10 is a spring for urging the armature 1 in the valve closing direction (left side in FIG. 1), and the reference numeral 11 is a non-magnetic portion for regulating the magnetic path so that the magnetic path passes through the inside of the armature 1.
[0018]
FIG. 2 shows the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the direction of the armature axis in a steady state when the valve-opening drive current flows, and the valve closing through the valve-closing drive solenoid. FIG. 5 is a diagram showing a direction of a driving current with respect to an armature axis direction, which is compared with a direction in a steady state when a valve closing driving current is supplied. Specifically, FIG. 2A shows the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid with respect to the direction of the armature axis. FIG. 9 is a diagram of the present embodiment in which the direction of the valve-closing drive current flowing through the solenoid coil with respect to the armature axis direction is the same as that in the steady state when the valve-closing drive current is applied, in the steady state. . On the other hand, FIG. 2B shows the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid shown in the present embodiment (FIG. 2A) for comparison with the armature axis direction. The one in the steady state when the valve-opening drive current is applied and the one in the steady state when the valve-closing drive current flowing through the coil of the valve-closing drive solenoid is oriented in the direction of the armature axis and the valve-closing drive current is applied. It is a figure in the case of arrange | positioning so that it may become a reverse direction.
[0019]
In FIG. 2 (a), L is the axial direction of the armature, 12 is the coil of the solenoid 2 for driving the valve opening, 13 is the coil of the solenoid 3 for driving the valve closing, and 22 is the valve opening which flows through the coil 12 of the solenoid 2 for driving the valve opening. The direction 23 of the drive current with respect to the armature axis direction L is the direction of the valve closing drive current flowing through the coil 13 of the valve closing drive solenoid 3 with respect to the armature axis direction L. Reference numeral 32 denotes a magnetic flux direction formed when the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 is steady. Reference numeral 33 denotes a magnetic flux direction formed when the valve-closing drive current flowing through the coil 13 of the valve-close drive solenoid 3 is steady. Magnetic flux direction. Reference numeral 42 denotes an induced electromotive force direction generated during a transition when the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 decreases, and 43 denotes an increase in valve-closing drive current flowing through the coil 13 of the valve-opening drive solenoid 3. This is the direction of the induced electromotive force that occurs at the time of the transient. Note that the same reference numerals as those shown in FIG. 1 indicate the same parts or parts as those shown in FIG. In FIG. 2B, L 'is the direction of the armature axis, 101 is the armature, 112 is the coil of the solenoid 102 for driving the valve opening, 113 is the coil of the solenoid 103 for driving the valve closing, and 122 is the solenoid 102 for driving the valve opening. Is the direction of the valve-opening drive current flowing through the coil 112 with respect to the armature axis direction L ′, and 123 is the direction of the valve-closing drive current flowing through the coil 113 of the valve-closing drive solenoid 103 with respect to the armature axis direction L ′. 132 is a magnetic flux direction formed when the valve-opening drive current flowing through the coil 112 of the valve-opening drive solenoid 102 is steady, and 133 is formed when the valve-closing drive current flowing through the coil 113 of the valve-opening drive solenoid 103 is steady. Magnetic flux direction. Reference numeral 142 denotes an induced electromotive force direction generated during a transition when the valve-opening drive current flowing through the coil 112 of the valve-opening drive solenoid 102 decreases, and 143 denotes an increase in valve-closing drive current flowing through the coil 113 of the valve-opening drive solenoid 103. This is the direction of the induced electromotive force that occurs at the time of the transient.
[0020]
Before describing the effects of the present embodiment (FIG. 2A), FIG. 3 will be described. FIG. 3 is a graph showing the relationship between the valve opening drive signal, the valve closing drive signal, the current value flowing through the valve opening driving solenoid, the current value flowing through the valve closing driving solenoid, and the behavior of the valve element and time. These relationships are applied not only in the case of the present embodiment (FIG. 2A) but also in the case shown in FIG. 2B. As shown in FIG. 3, the valve opening drive signal is switched from OFF to ON at time T0, and is switched from ON to OFF at time T4. On the other hand, the valve closing drive signal is switched from OFF to ON at time T5, and is switched from ON to OFF at time T9. Accordingly, the value of the current flowing through the valve-opening drive solenoid increases from time T0 to time T1, is in a steady state in which the value is constant from time T1 to time T4, and is in a transient state in which it decreases from time T4 to time T6. Further, the value of the current flowing through the valve-closing drive solenoid is in a transient state in which the current increases from time T5 to time T7, is in a steady state in which the value is constant from time T7 to time T9, and decreases from time T9 to time T10. When energization of the valve-opening drive solenoid is started, a magnetic attraction force is generated in the valve-opening drive solenoid to attract the armature in the valve-opening direction. Therefore, the valve body is in the fully closed position between time T2 and time T3. To the fully open position against the force of the spring. On the other hand, when the energization of the valve-opening drive solenoid is terminated, the magnetic attraction force for the valve-opening drive solenoid to attract the armature in the valve opening direction disappears, and the armature is urged in the valve closing direction by a spring. Furthermore, when energization of the valve-closing drive solenoid is started, a magnetic attraction force is generated in the valve-closing drive solenoid to attract the armature in the valve closing direction. Therefore, the valve body moves from the fully open position to the fully closed position between time T9 and time T10.
[0021]
As shown in FIGS. 2A and 3, according to the present embodiment, the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 has a direction 22 with respect to the armature axis direction L, and the valve-opening drive is performed. In the steady state (time T1 to time T4) at the time of application of the use current (time T0 to time T6), the state is downward (FIG. 2A). Further, the direction of the valve closing drive current flowing through the coil 13 of the valve closing drive solenoid 3 with respect to the armature axis direction L is 23 and the steady state (time T7 to time T10) when the valve closing drive current is supplied (time T5 to time T10). The one at the time T9) is also directed downward (FIG. 2A). That is, the direction 22 of the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 with respect to the armature axis direction L, and the direction of the valve-closing drive current flowing through the coil 13 of the valve-closing drive solenoid 3 with respect to the armature axis direction L. 23 and the same direction.
[0022]
Therefore, when the energization of the valve-closing drive solenoid 3 is started (time T5) and the energization of the valve-opening drive solenoid 2 is ended almost at the same time (time T4), the valve-closing drive for which the energization is started is started. The induced electromotive force direction 43 in which the current flowing through the coil 13 of the solenoid 3 and generated in the transient state (time T5 to time T7) is the current flowing through the coil 12 of the valve-opening solenoid 2 whose energization is terminated. Then, the direction of the induced electromotive force 42 generated in the transient state (time T4 to time T6) is opposite to each other, and the respective induced electromotive forces cancel each other. In other words, the current flowing through the coil 13 of the valve-closing drive solenoid 3 that has been energized is generated by the induced electromotive force generated in the transient state (time T5 to time T7), so that the other valve-opening drive solenoid 2 is activated. Demagnetization of the generated magnetic attraction can be promoted. That is, the magnetic attraction force generated by the other valve-opening drive solenoid by the magnetic flux generated in the steady state (time T7 to time T9), which is the current flowing through the coil of the demagnetizing solenoid that has been energized, is generated. Unlike the one described in Japanese Patent Application Laid-Open No. Hei 7-198053, in which the current is flowing through the coil 13 of the valve-closing drive solenoid 3 in which the energization is started, the other valve-opening drive is performed during the time (time T5 to time T7). The magnetic attraction generated by the solenoid 2 for use can be demagnetized.
[0023]
In the case shown in FIG. 2B, the direction 122 of the valve-opening drive current flowing through the coil 112 of the valve-opening drive solenoid 102 with respect to the armature axis direction L ′ and when the valve-opening drive current is applied (time T0) In the steady state (time T1 to time T4) from time T6 to time T6, the state is downward (FIG. 2B). On the other hand, the direction 123 of the valve closing drive current flowing through the coil 113 of the valve closing drive solenoid 103 with respect to the armature axis direction L ′ is in a steady state (time T7) when the valve closing drive current is supplied (time T5 to time T10). To (time T9) are directed upward (FIG. 2B). That is, the direction 122 of the valve-opening drive current flowing through the coil 112 of the valve-opening drive solenoid 102 with respect to the armature axis direction L ′, and the armature axis direction L ′ of the valve-closing drive current flowing through the coil 113 of the valve-closing drive solenoid 103. The direction 123 is opposite to the direction 123.
[0024]
Therefore, when the start of energization to the valve-closing drive solenoid 103 (time T5) and the end of energization to the valve-opening drive solenoid 102 (time T4) are performed at approximately the same time, the valve-closing drive for which energization is started is started. The induced electromotive force direction 143, which is a current flowing through the coil 113 of the solenoid 103 and is generated in a transient state (time T5 to time T7), is a current flowing through the coil 112 of the valve-opening drive solenoid 102 that has been de-energized. Therefore, the induced electromotive force is in the same direction as the induced electromotive force direction 142 in which the one in the transient state (time T4 to time T6) is generated, and the respective induced electromotive forces are strengthened with each other. In other words, the current flowing through the coil 113 of the valve-closing drive solenoid 103, which has been energized, is generated by the induced electromotive force generated in the transient state (time T5 to time T7). The demagnetization of the generated magnetic attraction is hindered. That is, the demagnetization of the magnetic attraction generated by the other valve-opening drive solenoid 102 is delayed.
[0025]
FIG. 4 shows the time (T5-T4) required from the time when the valve opening drive signal is switched from ON to OFF to the time when the valve closing drive signal is switched from OFF to ON, and the time after the valve opening drive signal is switched from ON to OFF. It is the graph which showed the relationship with time Tc (= T8-T4) required until a valve body was located in a fully closed position. As shown in FIG. 4, even if the time (T5−T4) required from when the valve opening drive signal is switched from ON to OFF to when the valve closing drive signal is switched from OFF to ON is slightly changed, the valve opening drive signal is changed. The time Tc (= T8−T4) required from when the signal is switched from ON to OFF to when the valve body is at the fully closed position is always the same as in FIG. 2A in the present embodiment (FIG. 2A). It becomes shorter than the case shown in FIG. That is, as in the case of the present embodiment (FIG. 2A), the direction of the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 with respect to the armature axis direction L is 22 and the valve-opening drive current is supplied. In a steady state when the valve closing drive current flowing through the coil 13 of the valve closing drive solenoid 3 is in the direction 23 with respect to the armature axis direction L, and in the steady state when the valve closing drive current is supplied. 2B, the direction 122 of the valve-opening drive current flowing through the coil 112 of the valve-opening drive solenoid 102 with respect to the armature axis direction L ′ as shown in FIG. 2B. The current in the steady state when the valve-opening drive current is applied and the valve-closing drive current flowing through the coil 113 of the valve-closing drive solenoid 103 in the armature axis direction L ′. Rather than in the normal direction when the valve-closing drive current is supplied, the valve is completely closed after the valve-opening drive signal is switched from ON to OFF. Can be shortened, that is, the valve closing responsiveness can be improved. As shown in FIG. 4, the valve closing response is optimal when the time T5 when the valve closing drive signal is switched from OFF to ON is slightly earlier than the time T4 when the valve opening drive signal is switched from ON to OFF. It becomes.
[0026]
In summary, according to the present embodiment, first, not only can the armature 1 be driven to open by supplying a valve-opening drive current to the valve-opening drive solenoid 2, but also the valve-closing drive The armature 1 can be driven to close by energizing the solenoid 3 with a valve closing drive current. That is, according to the present embodiment, the valve-closing responsiveness can be improved as compared with the case where the valve-closing drive solenoid is not provided. In addition, by providing the valve closing drive solenoid, the force of the spring 10 can be reduced, and the maximum operating fuel pressure can be improved.
[0027]
Second, when the start of energization of the valve-closing drive solenoid 3 (time T5) and the end of energization of the valve-opening drive solenoid 2 (time T4 to time T6) are performed almost simultaneously, The direction 122 of the valve-opening drive current flowing through the coil 112 of the solenoid 102 with respect to the armature axis direction L ′ in the steady state when the valve-opening drive current is applied, and the direction of closing the valve-opening drive solenoid 103 flowing through the coil 113. The direction 123 of the valve driving current with respect to the armature axis direction L ′, which is not arranged so as to be in the same direction as that in the steady state when the valve driving current is supplied (FIG. 2B). Valve responsiveness can be improved, and the dynamic range can be improved.
[0028]
Third, a current flowing through the coil of the degaussing solenoid that has been energized and demagnetizing the magnetic attraction generated by the other valve-opening drive solenoid by a magnetic flux generated in a steady state is disclosed in Japanese Patent Application Laid-Open No. H07-19764. Unlike the one described in Japanese Patent Application Publication No. 198053, the other valve-opening drive solenoid 2 is generated when the current flowing through the coil 13 of the valve-closure drive solenoid 3 is turned on (time T5 to time T7). This can demagnetize the magnetic attraction force. That is, according to the present embodiment, the magnetic attraction force generated by the valve-opening drive solenoid 2 at the time of transition (time T5 to time T7), but not at the time of steady state of the current flowing through the coil 13 of the valve-closing drive solenoid 3. Can be demagnetized.
[0029]
Further, according to the present embodiment, the valve opening drive solenoid 2 is disposed at one longitudinal end of the armature 1 and the valve closing drive solenoid 3 is disposed at the other longitudinal end of the armature 1. The valve-opening drive solenoid 2 and the valve-closing drive solenoid 3 make it possible to reliably perform the valve-closing drive and the valve-closing drive solenoid 3 as compared with the case where the solenoid for valve-closing and the solenoid for valve-closing drive are arranged at the same position in the longitudinal direction of the armature. it can.
[0030]
Further, according to the present embodiment, the demagnetization of the magnetic attraction force generated by the other solenoid 2 is promoted by the induced electromotive force generated in the transient state in the coil 13 of the one solenoid 3. As described above, the direction 22 of the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 with respect to the armature axis direction L in a steady state when the valve-opening drive current is applied is different from that in the steady state. The direction 23 of the valve closing drive current flowing through the coil 13 with respect to the armature axis direction L is arranged in the same direction as that in the steady state when the valve closing drive current is supplied. Therefore, unlike one in which the current flowing through the coil of one solenoid is demagnetized by the magnetic flux generated in the steady state and generated by the other solenoid (Japanese Patent Laid-Open No. 7-198053), When the current flowing through the third coil 13 transitions, the magnetism generated by the other solenoid 2 can be demagnetized.
[0031]
Furthermore, according to the present embodiment, the magnetic force remaining in the valve-opening drive solenoid 2 after the power-on to the valve-opening drive solenoid 2 is terminated by the induced electromotive force generated during the transition after the power-on to the valve-closing drive solenoid 3 is started. The direction 22 of the valve-opening drive current flowing through the coil 12 of the valve-opening drive solenoid 2 with respect to the armature axis direction L in a steady state when the valve-opening drive current is applied so that demagnetization of the attraction force is promoted. And the direction 23 of the valve-closing drive current flowing through the coil 13 of the valve-closing drive solenoid 3 with respect to the armature axis direction L, so that the direction is the same as that in the steady state when the valve-closing drive current is supplied. Is done. For this reason, unlike a valve in which the magnetic attraction force remaining in the other solenoid is demagnetized by a magnetic flux generated in a steady state after the energization of the valve-opening drive solenoid is started (Japanese Patent Laid-Open No. 7-198053), At the time of transition after the start of energization of the solenoid 2, the magnetic attraction force remaining in the valve-opening drive solenoid 2 can be demagnetized.
[0032]
【The invention's effect】
According to the first aspect of the present invention, the armature can be driven to open and the armature can be driven to close. Furthermore,Unlike the current flowing through the coil of one solenoid that demagnetizes the magnetism generated by the other solenoid by the magnetic flux generated in the steady state, the other current flows through the coil of one solenoid during the transition of the other. It can demagnetize the magnetism generated by the solenoid,Valve closing responsiveness can be improved.
[0033]
According to the second aspect of the invention, the valve opening drive by the valve opening drive solenoid and the valve closing drive by the valve closing drive solenoid can be reliably performed.Also, unlike magnetic flux generated in the steady state after the start of energization of the valve-opening drive solenoid, the magnetic attraction force remaining in the other solenoid is demagnetized. It is possible to demagnetize the magnetic attraction force remaining in the valve opening drive solenoid.
[Brief description of the drawings]
FIG. 1 is a partial sectional side view of one embodiment of a fuel injection valve for an internal combustion engine of the present invention.
FIG. 2 shows the orientation of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid in the steady state when the valve-opening drive current is applied and the direction of the valve-opening drive current flowing through the coil of the valve-opening drive solenoid. FIG. 5 is a diagram showing the direction of the valve driving current with respect to the armature axis direction, which is compared with that in a steady state when the valve closing driving current is supplied.
FIG. 3 is a graph showing a relationship between a valve opening drive signal, a valve closing drive signal, a current value flowing through a valve opening driving solenoid, a current value flowing through a valve closing driving solenoid, and valve behavior and time.
FIG. 4 is a graph showing the time required (T5-T4) from when the valve-opening drive signal is switched from ON to OFF to when the valve-closing drive signal is switched from OFF to ON, and when the valve-opening drive signal is switched from ON to OFF. 5 is a graph showing a relationship between the time Tc (= T8−T4) required until the valve element is located at the fully closed position from FIG.
[Explanation of symbols]
1 ... Armature
2. Solenoid for valve opening drive
3. Solenoid for valve closing drive
12 ... Coil of solenoid for valve opening drive
13 ... Coil of solenoid for valve closing drive
22: Direction of valve opening drive current to armature axis
23: Direction of the valve closing drive current with respect to the armature axis direction
L: Armature axial direction

Claims (2)

An armature, a valve-opening drive solenoid that is energized with a valve-opening drive current to open the armature, and a valve-closing drive that is energized with a valve-closing drive current to drive the armature closed. A fuel injection valve for an internal combustion engine comprising a solenoid and a valve opening drive current flowing through a coil of the valve opening drive solenoid with respect to an armature axis direction and in a steady state when a valve opening drive current is supplied. The direction of the valve-closing drive current flowing through the coil of the valve-closing drive solenoid with respect to the armature axis direction is the same as that in the steady state when the valve-closing drive current is supplied, and the coil of one solenoid is turned on. The induced electromotive force generated by the flowing current in the transient state promotes the demagnetization of the magnetism generated by the other solenoid. For an internal combustion engine fuel injection valve is fit. The armature is constituted by a single armature, the valve opening drive solenoid is disposed at one longitudinal end of the armature, the valve closing drive solenoid is disposed at the other longitudinal end of the armature, and the valve closing drive is provided. 2. An induced electromotive force generated at the time of transition after the start of energization of the solenoid for valve opening accelerates the demagnetization of the magnetic attraction force remaining in the solenoid for valve opening drive after the energization of the solenoid for valve opening drive ends. 3. A fuel injection valve for an internal combustion engine according to claim 1.

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