JP2003083097A - Solenoid valve driving device for engine for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce consumption electric power of solenoid valve driving device during idle stop control and obtain the reduction effect of fuel consumption amount by idle stop control to the maximum extent in an engine for a vehicle in which intake and exhaust valves are opened and closed by the solenoid valve driving device to perform idle stop control. SOLUTION: The exhaust valve is opened after stop conditions for the engine are satisfied (S11). If there is a cylinder which is in a condition before fuel injection is started for preparing next combustion, this cylinder is judged to be a combustion end cylinder (S12). The intake valve is held at a close position from the cylinder which is judge to be the combustion end cylinder sequentially (S13B). Current carrying to an electromagnetic coil on an exhaust valve side is shut off to hold the exhaust valve at a neutral position (S14B).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic valve drive system for a vehicle engine, and more particularly to control of intake and exhaust valves in an idle stop state.

[0002]

2. Description of the Related Art Conventionally, there is known a vehicle which is generally called an idle stop and is configured to automatically stop the engine when the vehicle is stopped (see Japanese Patent Application Laid-Open No. 8-291725). Also, as an opening / closing drive device for an intake / exhaust valve of an engine, an electromagnetic valve drive device is known in which the intake / exhaust valve is opened / closed by an electromagnetic force generated by an electromagnetic coil instead of an opening / closing drive mechanism using a cam shaft. 9-3031
22).

[0003]

By the way, when an engine having a valve opening / closing drive mechanism using a general camshaft and the idle stop control are combined, an engine stop condition is satisfied and fuel injection is stopped. After that, the intake and exhaust valves are opened and closed by the cam shaft while the engine is rotating, and after the engine is stopped, the valve position at the time of stop is maintained.

Here, it is possible to replace the above-mentioned opening / closing driving mechanism by the cam shaft with an electromagnetic valve driving device to drive the intake / exhaust valve in the same manner, but in the electromagnetic valve driving device, the valve is opened / closed. Consumes power,
Also, even when the intake and exhaust valves are held in the open position or the closed position, it is necessary to continue to generate electromagnetic force,
A large amount of unnecessary electric power is consumed during idle stop where engine output is not required, and as a result, there arises a problem that the effect of reducing fuel consumption due to idle stop cannot be maximized.

The present invention has been made in view of the above problems, and reduces the power consumption of the electromagnetic valve driving device during the idle stop control in the combination of the engine having the electromagnetic valve driving device and the idle stop control. Therefore, it is an object of the present invention to provide an electromagnetic valve drive device for a vehicle engine that can maximize the effect of reducing fuel consumption by idle stop.

It is another object of the present invention to be able to complete the start in a short time when the engine is restarted from the idle stop state.

[0007]

Therefore, an electromagnetic valve drive system for a vehicle engine according to the first aspect of the invention is
In a vehicle engine in which idle stop control is performed to automatically stop the engine when the vehicle is stopped, an intake / exhaust valve that is biased to a neutral position by an elastic body is an electromagnetic valve drive device that opens and closes by an electromagnetic force by an electromagnetic coil, When the engine stop condition is satisfied by the idle stop control, the intake / exhaust valve is held at a predetermined position irrelevant to the engine rotation position.

According to the above construction, when the engine stop condition is satisfied such as when the vehicle is stopped, the open / close drive mechanism based on the cam shaft is driven to a position corresponding to the rotational position of the engine. The intake and exhaust valves are held at a predetermined position irrelevant to the rotational position of the engine, and the opening / closing drive can be stopped before the engine rotation is stopped and the power can be forcibly held at a position where the power consumption is zero.

Since fuel injection and the like are stopped when the engine stop condition is satisfied, the engine stop condition is satisfied after the engine stop condition is determined to be satisfied.
If the intake / exhaust valve is held at a predetermined position, including the time until the engine rotation actually stops, the opening / closing drive with a camshaft opening / closing drive mechanism can be performed. Under repeated conditions, the intake / exhaust valve will hold a constant position.

According to the second aspect of the present invention, at least one of the electromagnetic coil for driving the opening / closing of the intake valve and the electromagnetic coil for driving the opening / closing of the exhaust valve is held in a deenergized state,
It is configured to be held at a neutral position corresponding to the power-off state. According to the above structure, the energization of the electromagnetic coil for opening and closing at least one of the intake valve and the exhaust valve is stopped, the valve position is held at a neutral position irrelevant to the engine rotation position, and the energization is stopped. The power consumption in is 0.

According to the third aspect of the present invention, both the electromagnetic coil that drives the intake valve to open and close and the electromagnetic coil that drives the exhaust valve to open and close are held in the non-energized state, and the intake valve and the exhaust valve are in the non-energized state. It is configured to be held in a neutral position. According to the above configuration, the energization to the opening / closing driving electromagnetic coils of both the intake valve and the exhaust valve is stopped, both the intake valve and the exhaust valve are held in the neutral position, and the power consumption in the electromagnetic coil of the electromagnetic valve drive device is reduced to zero. And

According to the fourth aspect of the invention, the intake valve is held in the closed position and the exhaust valve is held in the open position.
According to the above configuration, the intake / exhaust valve is held in the open position or the closed position, not in the neutral position which needs to be initialized at the time of restart, and the intake valve controls the fuel injected into the intake port into the cylinder. The exhaust valve is held in a closed position for blocking suction, and the exhaust valve is held in an open position for opening the inside of the cylinder.

According to the fifth aspect of the present invention, while holding the intake valve in the closed position, the electromagnetic coil that drives the exhaust valve to open and close is held in the non-energized state, and the exhaust valve is placed in the neutral position corresponding to the non-energized state. It is configured to be held. According to the above configuration, the power consumption on the exhaust valve side is 0 due to the stop of energization, and the inside of the cylinder is opened by holding the exhaust valve in the neutral position, and the intake valve does not need to be initialized when restarting. And is held in the closed position that prevents the fuel injected into the intake port from being sucked into the cylinder.

According to the sixth aspect of the present invention, the intake / exhaust valve is moved to a predetermined position after the engine stop condition is satisfied by the idle stop control. According to the above configuration, even if the engine stop condition is satisfied and the fuel injection is stopped, the combustion exhaust of the last injected fuel remains at the position corresponding to the engine rotational position until it is discharged through the exhaust valve. Since it is necessary to open and close the intake and exhaust valves, the transition to a position irrelevant to the rotational position of the engine is delayed by the time when combustion is expected to end in all cylinders.

According to the seventh aspect of the present invention, after the engine stop condition is satisfied by the idle stop control, the position of the intake / exhaust valve is sequentially shifted to a predetermined position from the cylinder for which the combustion end is determined. According to the above configuration,
After the engine stop condition is satisfied, the end of combustion is determined for each cylinder, and the valve position is sequentially switched from the cylinder that is determined to end combustion and is allowed to shift to a valve position irrelevant to the engine rotation position.

According to the eighth aspect of the present invention, after the engine stop condition is satisfied by the idle stop control, the combustion end determination is made for the cylinder that has experienced the state in which the exhaust valve is in the open position and before the fuel injection for the next combustion is started. It is configured to perform. According to the above configuration, after the engine stop condition is satisfied,
By experiencing the open state of the exhaust valve (exhaust stroke), the combustion exhaust of the fuel injected before the conditions are met can be discharged normally, but the next combustion is prepared upstream of the intake valve during the exhaust stroke. If the fuel injection is started when the engine stop condition is satisfied, it is necessary to continue opening and closing the valve according to the engine rotation position until the next exhaust stroke. Even if the open state is experienced, the combustion end determination is not performed, and the combustion end determination is delayed until the next exhaust stroke.

[0017]

According to the present invention, the intake / exhaust valve is held at a position irrelevant to the rotational position of the engine while the engine is stopped by the idle stop control, thereby avoiding unnecessary opening / closing drive. It is possible to reduce the power consumption in the holding state and / or the holding state, and thus, it is possible to maximize the effect of reducing the fuel consumption amount by the idle stop.

According to the second aspect of the present invention, by holding at least one of the intake and exhaust valves in the neutral position where no power is consumed, compared to the case where both of the intake and exhaust valves are held in the open position or the closed position. There is an effect that the power consumption in the idle stop state can be reduced to at least about half. According to the third aspect of the present invention, by holding both the intake and exhaust valves in the neutral position where no power is consumed, there is an effect that the power consumption in the idle stop state can be reduced to the maximum.

According to the fourth aspect of the present invention, the intake valve is held closed and the exhaust valve is held open so that the intake / exhaust valve is adsorbed from the neutral position to the open or closed position when restarting from the idle stop state. Initialization is unnecessary, and by holding the intake valve in the closed position, fuel can be immediately injected to the upstream side of the intake valve when restarting,
Moreover, by holding the exhaust valve in the open position, it is possible to avoid the occurrence of pumping loss during cranking, to quickly increase the cranking speed, and to restart the engine in a short time. effective.

According to the fifth aspect of the present invention, by holding the intake valve in the closed position, it is not necessary to initialize the intake valve from the neutral position to the open or closed position when restarting from the idle stop state. Also, while fuel can be immediately injected to the upstream side of the intake valve at the time of restart, by holding the exhaust valve in the neutral position, the power consumption on the exhaust valve side can be made almost zero, and at the time of cranking. There is an effect that the cranking speed can be increased promptly while avoiding the occurrence of pumping loss in.

According to the sixth aspect of the present invention, the switching of the intake / exhaust valve to the holding position is delayed after the engine stop condition is satisfied. Therefore, the intake / exhaust valve burns during the combustion cycle that should be continued after the condition is satisfied. It is controlled at a position irrelevant to the cycle, and it is possible to prevent afterburn and smoldering of the spark plug from occurring.

According to the seventh aspect of the present invention, the combustion end determination is performed for each cylinder, and the cylinders in which the last combustion cycle is completed are sequentially switched to the holding positions of the intake and exhaust valves. There is an effect that the exhaust valve can be switched to a state in which power consumption can be reduced as quickly as possible. According to the invention described in claim 8, the end of combustion can be easily determined by determining the open state of the exhaust valve for each cylinder, and the exhaust stroke after the fuel injection for the next combustion is started. There is an effect that it is possible to avoid making an erroneous determination that the combustion has ended.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a traveling drive source of a hybrid vehicle according to an embodiment, which includes an engine 1 and an electric motor 2 as a traveling drive source, and either one of the engine 1 and the electric motor 2 depending on traveling conditions or Configured to run on both.

The electric motor 2 is directly connected to the output shaft of the engine 1, and the driving force generated by one or both of the engine 1 and the electric motor 2 serves as a torque converter 3 and a continuously variable transmission (CVT). It is transmitted to a drive wheel (not shown) via 4. The electric motor 2 not only generates the driving force of the vehicle but also starts the engine 1, and further functions as a generator to regenerate energy during braking.

The inverter 5 is a vector control inverter, which converts the DC power of the battery 6 into three-phase AC power and supplies the three-phase AC power to the electric motor 2 to generate a driving force from the electric motor 2 and regenerative AC of the electric motor 2. The power is converted into DC power and supplied to the battery 6 to charge the battery 6. The engine 1 is a 4-cycle gasoline engine including an intake valve 19A and an exhaust valve 19B (see FIG. 2) for each cylinder, and the intake valve 19A, 20B is controlled by an electromagnetic valve drive device 20A, 20B as shown in FIG.
The exhaust valves 19B are individually opened and closed.

The electromagnetic valve drive units 20A, 2 shown in FIG.
Reference numeral 0B denotes a housing 21 made of a non-magnetic material provided on the cylinder head, an armature 22 integrally provided on the stem 27 of the intake / exhaust valves 19A and 19B and movably accommodated in the housing 21, and the armature 22.
So as to generate an electromagnetic force that closes the intake / exhaust valves 19A and 19B by a valve closing electromagnetic coil 23 disposed inside the housing 21 so as to face the upper surface of the armature 22 and the armature 22 is sucked. Intake and exhaust valve 1
The housing 21 is opposed to the lower surface of the armature 22 so as to generate an electromagnetic force for opening the valves 9A and 19B.
A solenoid valve 24 for opening the valve, a return spring 25 (elastic body) on the valve closing side that biases the armature 22 toward the valve closing direction of the intake and exhaust valves 19A and 19B, and intake and exhaust valves 19A and 19B. Toward the valve opening direction of the armature 22
And a valve opening side return spring 26 (elastic body) for urging the valve.

When both the valve-closing electromagnetic coil 23 and the valve-opening electromagnetic coil 24 are de-energized, the intake / exhaust valves 19A and 19B have the valve-closing side return spring 25 and the valve-opening side return spring 26. The spring force of and elastically supports the neutral position between the fully open position and the fully closed position. In the above configuration, for example, when fully closed, energization of the valve opening electromagnetic coil 24 is stopped, the valve closing electromagnetic coil 23 is energized to generate an electromagnetic force, and the armature 22 is attracted to the valve closing electromagnetic coil 23. .

When opening the valve from the fully closed position, the energization of the valve closing electromagnetic coil 23 is stopped and the valve element is moved in the valve opening direction by the reaction force of the valve opening side return spring 26. The valve-opening electromagnetic coil 24 is energized to generate an electromagnetic force to attract the armature 22 to the valve-opening electromagnetic coil 24 and hold it in the fully open position. Further, when the valve is closed from the state of being held in the fully open position, the valve opening electromagnetic coil 2
4 is stopped and the valve body is moved in the valve closing direction by the reaction force of the valve closing side return spring 25, while the valve closing electromagnetic coil 2
3 is energized to generate an electromagnetic force so that the armature 22 is attracted to the valve closing electromagnetic coil 23 and held in the fully closed position.

By repeating such an operation periodically, the function as the valve operating device of the engine 1 is achieved. Incidentally, when the energization of both the valve closing electromagnetic coil 23 and the valve opening electromagnetic coil 24 is stopped, the intake and exhaust valves 19A and 19B are neutralized by the valve closing side return spring 25 and the valve opening side return spring 26. Since it is elastically supported at the position, when performing the above-mentioned opening / closing operation, first, initialization control for displacing the intake / exhaust valves 19A, 19B from the neutral position to the fully closed position or the fully opened position is performed. There is a need to do.

As the initialization control, for example, the valve closing electromagnetic coil 23 and the valve opening electromagnetic coil 24 are alternately energized at a cycle corresponding to the natural frequency of the spring-mass system of the electromagnetic valve driving devices 20A and 20B. By repeating the above, the valve element gradually vibrates from the neutral position with increasing amplitude and vibrates, and finally the valve closing electromagnetic coil 23 or the valve opening electromagnetic coil 24 is held so as to be held at the fully open position or the fully closed position. There is control using a resonance phenomenon to shift to the energized holding state.

In FIG. 1, a control unit 7 comprises a microcomputer, controls the inverter 5 to control the rotation speed and torque of the electric motor 2, and controls the rotation speed and torque of the electric motor 2 through an intake passage 8 of the engine 1. By controlling the electronically controlled throttle valve 9 mounted on the engine 1,
By controlling the intake air amount, and by controlling a fuel injection valve and a power transistor (not shown), fuel injection into the engine 1 and ignition by a spark plug are controlled.

Further, the control unit 7 includes the electromagnetic valve drive device 20 according to the rotational position of the engine 1.
The intake / exhaust valves 19A and 19B are opened and closed by controlling A and 20B. The control unit 7 includes a vehicle speed sensor 11 for detecting a vehicle speed, an accelerator sensor 12 for detecting an accelerator opening, a water temperature sensor 13 for detecting a cooling water temperature of the engine 1, and a crank angle sensor 14 for detecting a crank angle of the engine 1. , A motor rotation sensor 15 for detecting the rotation speed of the electric motor 2, a motor current sensor 16 for detecting a three-phase AC current of the electric motor 2, and a brake switch 17 which is turned on when the amount of depression of a brake pedal (not shown) exceeds a predetermined value. A signal from the etc. is input.

Next, the idle stop control in the above system configuration will be described with reference to the flowchart of FIG. In step S41, it is determined whether or not a stop command flag for giving a stop command to the engine 1 and the electric motor 2 is set. When 1 is set, the process proceeds to step S47 and is reset to 0. If so, the process proceeds to step S42.

When the stop command flag is reset to 0, it is determined in step S42 whether the brake pedal is depressed by the brake switch 17. When the brake pedal is depressed, the process proceeds to step S43, and when the brake pedal is not depressed, the process ends. In step S43, the vehicle speed sensor 1
1 determines whether the vehicle speed is substantially 0, that is, whether the vehicle is stopped.

If the vehicle is stopped, the process proceeds to step S44,
If the vehicle speed is not substantially 0 and the vehicle is traveling, the process ends. When the vehicle is in the stopped state, in step S44, a timer for counting the elapsed time after the vehicle is stopped is started. In step 45, it is determined whether or not 3 seconds or more have elapsed since the vehicle was stopped based on the timed value of the timer. Until 3 seconds or more have elapsed, the process returns to step S43 and the above processing is repeated for 3 seconds. After the above, step S
Proceed to 46.

When the brake pedal is depressed, the vehicle speed is almost zero.
If 3 seconds or more have elapsed since the vehicle stopped, the stop command flag is set to 1 in step S46, and the process ends. The stop command flag is referred to by the control program of the engine 1 and the electric motor 2, and in response to the stop command flag being set to 1, the engine 1 and the electric motor 2 are stopped and the idle stop state is set.

When it is determined in step S41 that the stop command flag is set to 1, the process proceeds to step S47, and it is determined whether or not the brake pedal is released by the brake switch 17. Engine 1
When the electric motor 2 is in the idling stop state in which it is stopped and the brake pedal is not released, the processing is ended while the stop command flag is held at 1.

On the other hand, when the brake pedal is released in a state where the engine 1 and the electric motor 2 are stopped, that is, in the idle stop state, the process proceeds to step S48 and the stop command flag is reset to zero. The stop command flag is referred to by the control program of the engine 1 and the electric motor 2, and the engine 1 is started by the electric motor 2 in response to the stop command flag being reset to zero.

During normal operation of the engine 1, the control unit 7 controls the electromagnetic valve drive units 20A and 20B according to the rotational position of the engine 1 to synchronize the intake and exhaust valves 19A and 19B with the engine rotation. Although it is opened and closed, the electromagnetic valve drive units 20A and 20B are controlled as described below during the idle stop control.

The flowchart of FIG. 4 shows that the electromagnetic valve drive devices 20A, 20 during the idle stop control are executed.
3 shows a first embodiment of B control. Step S
At 1, it is determined whether the engine stop condition in the idle stop control is satisfied and 1 is set in the stop command flag. When the stop command flag is set to 1, the process proceeds to step S2, and it is determined whether or not a preset delay time has elapsed since the stop command flag was switched from 0 to 1.

The delay time is 0 when the stop command flag is 0.
After switching from 1 to 1 (after the engine stop condition is satisfied), it is set based on the maximum value of the time required to complete the combustion of fuel and the discharge of combustion exhaust gas in all cylinders,
When the delay time has elapsed, in all cylinders,
It is estimated that the combustion (up to the exhaust corresponding to the last combustion) has ended.

When it is determined in step S2 that the delay time has elapsed, the process proceeds to step S3, in which the energization of the electromagnetic valve drive devices 20A (electromagnetic coils) on the intake valve 19A side of all cylinders is simultaneously cut off. In the next step S4,
Electromagnetic valve drive device 20 on the exhaust valve 19B side of all cylinders
The power to B (electromagnetic coil) is cut off at the same time. As a result, the intake / exhaust valves 19A and 19B are held at the neutral position irrelevant to the rotational position of the engine 1.

Immediately after the delay time elapses, the engine 1 continues to rotate by inertia. Therefore, the energization stop control is started during the inertia rotation, and the opening / closing drive synchronized with the engine rotation is continued. Compared with the case, it is possible to reduce the power consumption of the electromagnetic valve drive devices 20A and 20B during inertial rotation. In addition, the intake / exhaust valve 1 is placed at the open position or the closed position corresponding to the position where the engine is completely stopped.
A holding current is required to hold 9A and 19B, but if the energization is stopped as described above, the power consumption after the delay time after the idle stop condition is satisfied is 0.
Becomes

By reducing the power consumption during the inertial rotation and after the stop, it is possible to maximize the effect of reducing the fuel consumption by the idle stop. Further, since the end of combustion in all cylinders is determined based on the elapsed time after the engine stop condition is satisfied, the intake and exhaust valves 19A and 19B are controlled to the neutral position before the end of combustion,
It is possible to avoid causing afterburn and smoldering of the spark plug.

In the first embodiment, the intake / exhaust valve 19
Both A and 19B are held in the neutral position, while in FIG.
In the second embodiment shown in the flowchart of FIG. 5, the intake valve 19A is held in the closed position (step S3A),
The exhaust valve 19B is held in the open position (step S4A). In the case of the second embodiment, by holding the intake valve 19A in the closed position and the exhaust valve 19B in the open position while the engine 1 is rotating by inertia, the opening / closing is performed according to the engine rotation. It is possible to reduce power consumption as compared with the case of driving.

Further, since the initialization control is not required at the time of restarting from the idle stop state, and since the intake valve 19A is kept in the closed position, if the structure is such that fuel is injected upstream of the intake valve 19A, It is possible to inject fuel immediately after the start determination to retain the fuel on the upstream side of the intake valve 19A, and to hold the exhaust valve 19B in the open position, thereby reducing pumping loss during cranking. The cranking rotation speed can be increased faster, and the start-up can be completed in a short time.

In the second embodiment, the intake valve 19A
Is held in the closed position and the exhaust valve 19B is held in the open position, whereas in the third embodiment shown in the flowchart of FIG. 6, the intake valve 19A is held in the closed position (step S3B). For 19B, the valve closing electromagnetic coil 23 and the valve opening electromagnetic coil 24 are de-energized and held at the neutral position (step S4B).

According to the third embodiment described above, the intake / exhaust valves 19A, 19A and 19A are maintained while the engine 1 is rotating by inertia.
Since the opening / closing of B according to the engine rotation is stopped, it is possible to reduce the power consumption, and even after the engine 1 is completely stopped, the electromagnetic valve drive device 20B on the exhaust valve 19B side consumes no power. Becomes 0, and the power consumption while the engine 1 is stopped can be significantly reduced.

Although it is necessary to control the initialization of the exhaust valve 19B at the time of restart, the intake valve 19A can be held in the closed position to quickly start the fuel injection, and the exhaust valve 19B can be moved to the neutral position. Therefore, it is possible to obtain the effect of reducing the pumping loss during cranking, and it is possible to start the engine 1 with necessary and sufficient responsiveness.

By the way, in the above first to third embodiments,
At the time when a predetermined delay time elapses after the stop condition of the engine 1 is satisfied, the intake and exhaust valves 19A, 19A, 1
9B is held at a predetermined position that is irrelevant to the rotational position of the engine 1. However, the combustion end timing differs between cylinders due to the stroke phase difference. Accordingly, it is necessary to switch the positions of the intake / exhaust valves 19A and 19B to positions irrelevant to the rotational position of the engine 1.

Therefore, in the cylinder in which the combustion ends early, the valve position can be switched more quickly, but the actual switching is delayed according to the cylinder in which the combustion ends last. Therefore, the combustion end determination is performed for each cylinder, and the intake and exhaust valves 19A, 19A
By switching the position B to a position irrelevant to the rotational position of the engine 1, it is possible to further reduce power consumption.

The flowchart of FIG. 7 shows that the intake / exhaust valve 19 is determined for each cylinder by determining the combustion end for each cylinder as described above.
The 4th embodiment which changes the position of A and 19B is shown. In step S11, it is determined whether or not the engine stop condition in the idle stop control is satisfied and the stop command flag is set to 1. When the engine stop condition is satisfied and the stop command flag is set to 1, the process proceeds to step S12.

In step S12, the termination of combustion is determined for each cylinder based on whether or not there is a cylinder in which the exhaust valve 19B is opened and the exhaust stroke is reached after the engine stop condition is satisfied. If the exhaust stroke is experienced after the engine stop condition is satisfied, the end of the last combustion cycle including the time when the engine stop condition is satisfied can be estimated, but fuel injection for the next combustion is started during the exhaust stroke. In this case, when the engine stop condition is met, if the exhaust stroke is in progress and fuel injection has already started, the next exhaust stroke ends combustion in that cylinder.

Therefore, in step S12, it is determined whether or not there is a cylinder in which the exhaust valve 19B is open and before the start of fuel injection for the next combustion. Step S1
When it is determined in step 2 which cylinder meets the above conditions, the process proceeds to steps S13 and S14, and the intake / exhaust valve 19 of the cylinder is
The energization of the electromagnetic valve drive units 20A and 20B of A and 19B is stopped, and the intake and exhaust valves 19A and 19B are held at the neutral position.

The process of steps S13 and S14 will be described with reference to FIG.
As in the fifth embodiment shown in the flowchart of FIG. 5, the intake valve 19A of the cylinder is held in the closed position (step S1).
3A), the exhaust valve 19B of the cylinder can be replaced with a configuration in which the exhaust valve 19B is held in the open position (step S14A). Further, as in the sixth embodiment shown in the flowchart of FIG. 9, the intake valve 19A of the cylinder is held in the closed position in the processes of steps S13 and 14 (step S13).
B), the electromagnetic valve drive device 20B on the exhaust valve 19B side of the cylinder can be replaced with a configuration in which the exhaust valve 19B is held in the neutral position by cutting off the energization (step S14B).

In step S15, it is determined whether combustion has ended for all cylinders, and it is determined whether the valve position has been switched to a position irrelevant to the rotational position of the engine 1, and if there is a cylinder for which combustion end has not been determined. Returns to step S12 and repeats the processing. It should be noted that the present invention is applicable to any vehicle engine 1 that is configured to perform idle stop control and that includes an electromagnetic valve drive device, and includes the engine 1 and the electric motor 2 as a travel drive source. It is not limited to hybrid vehicles.

[Brief description of drawings]

FIG. 1 is a diagram showing a travel drive source of a hybrid vehicle including an electromagnetic valve drive device according to the present invention.

FIG. 2 is a cross-sectional view showing the structure of the electromagnetic valve driving device.

FIG. 3 is a flowchart showing idle stop control.

FIG. 4 is a flowchart showing a first embodiment of control of an intake / exhaust valve during idle stop.

FIG. 5 is a flowchart showing a second embodiment of control of an intake / exhaust valve during idle stop.

FIG. 6 is a flowchart showing a third embodiment of control of an intake / exhaust valve during idle stop.

FIG. 7 is a flowchart showing a fourth embodiment of control of an intake / exhaust valve during idle stop.

FIG. 8 is a flowchart showing a fifth embodiment of control of an intake / exhaust valve during idle stop.

FIG. 9 is a flowchart showing a sixth embodiment of control of an intake / exhaust valve during idle stop.

[Explanation of symbols]

1 ... engine 2 ... Electric motor 3 ... Torque converter 4 continuously variable transmission 5 ... Inverter 6 ... Battery 7 ... Control unit 8 ... Intake passage 9 ... Electric throttle valve 11 ... Vehicle speed sensor 12 ... Accelerator sensor 13 ... Water temperature sensor 14 ... Crank angle sensor 15 ... Motor rotation sensor 16 ... Motor current sensor 17 ... Brake switch 19A ... Intake valve 19B ... Exhaust valve 20A, 20B ... Electromagnetic valve drive device 22 ... Armature 23 ... Electromagnetic coil for valve closing 24 ... Electromagnetic coil for valve opening 25 ... Return spring on valve closing side 26 ... Return spring on valve opening side

Continued front page    F-term (reference) 3G018 AB09 AB16 CA09 CA12 DA83                       EA02 EA05 EA09 EA11 EA22                       EA33 FA06 GA37                 3G092 AA11 CA01 DA01 DA02 DA07                       DG09 FA24 FA30 GA10 HA06Z                       HE01Z HE03Z HE08Z HF08Z                       HF20Z HF21Z HF25Z                 3G093 BA19 BA22 DA01 DA05 DA06                       DA07 DA13 DB05 DB15 EA00

Claims (8)

[Claims] 1. An electromagnetic valve drive for opening and closing an intake / exhaust valve urged by an elastic body to a neutral position in an engine for a vehicle in which idle stop control is performed to automatically stop the engine when the vehicle is stopped. An electromagnetic device for a vehicle engine, characterized in that the intake / exhaust valve is held at a predetermined position irrelevant to the rotational position of the engine in a state where an engine stop condition is satisfied by the idle stop control. Valve drive. 2. An electromagnetic coil for opening / closing the intake valve and an electromagnetic coil for opening / closing the exhaust valve are held in a non-energized state and held in the neutral position corresponding to the non-energized state. The electromagnetic valve drive device for a vehicle engine according to claim 1, wherein: 3. The neutral coil which holds both the electromagnetic coil for driving the intake valve to open and close and the electromagnetic coil for driving the exhaust valve to open and close so that the intake valve and the exhaust valve correspond to the non-energized state. The electromagnetic valve drive device for a vehicle engine according to claim 1, wherein the electromagnetic valve drive device is held at a position. 4. The electromagnetic valve drive system for a vehicle engine according to claim 1, wherein the intake valve is held in a closed position and the exhaust valve is held in an open position. 5. While holding the intake valve in a closed position,
2. The electromagnetic coil for driving the exhaust valve to open and close is held in a non-energized state, and the exhaust valve is held in the neutral position corresponding to the non-energized state.
An electromagnetic valve drive device for an engine for a vehicle as described above. 6. The method according to claim 1, wherein, when the engine stop condition is satisfied by the idle stop control, the shift to the predetermined position is delayed and executed.
5. The electromagnetic valve drive device for a vehicle engine according to any one of 5 above. 7. After the engine stop condition is satisfied by the idle stop control, the cylinders for which the combustion end is determined are sequentially
The electromagnetic valve drive system for a vehicle engine according to any one of claims 1 to 5, wherein the position of the intake / exhaust valve is moved to the predetermined position. 8. A combustion end determination is performed for a cylinder that has experienced a state in which an exhaust valve is in an open position and fuel injection has not yet started in preparation for the next combustion after the engine stop condition is satisfied by the idle stop control. An electromagnetic valve drive device for a vehicle engine according to claim 7.