JP3028017B2 - Power supply device for driving auxiliary equipment of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor for driving a fuel pump for supplying fuel to an injector and an exhaust characteristic control for adjusting the characteristics of an exhaust system.
The present invention relates to an auxiliary device driving power supply device for an internal combustion engine that supplies driving power to an actuator that drives a regulating valve.

[0002]

2. Description of the Related Art In the present specification, the auxiliary equipment of an internal combustion engine means various devices attached to the internal combustion engine to operate the internal combustion engine.

[0003] In recent years, in order to improve the performance of an internal combustion engine, an electric type is often used as an auxiliary device of the engine. For example, in recent internal combustion engines, a fuel injection device is often used as a means for supplying fuel. In this case, an electric injector, a fuel pump for supplying fuel to the injector, and a drive for driving the fuel pump are provided. It requires a pump motor (electric motor).

In order to enhance the high speed performance of the engine, an exhaust valve for adjusting the characteristics (resonance frequency) of the exhaust system is provided.
By adjusting the exhaust valve when the engine is running at high speed, a standing wave is generated in the exhaust system to improve the exhaust efficiency and the air supply efficiency. In this case, however, it is necessary to drive the exhaust valve. Requires an electric actuator.

Further, a gasoline engine requires an ignition device and an electronic device such as a microcomputer to control the ignition timing and the fuel injection timing.

Conventionally, fuel injection devices and exhaust valves have been used exclusively for internal combustion engines such as vehicles equipped with a battery, but recently, even in vehicles equipped with no battery, the performance of the engine has been improved. The use of a fuel injection device or an exhaust valve or the use of an electronic device such as a microcomputer has been studied to improve the performance.

Therefore, in order to use the fuel injection device in an internal combustion engine such as a vehicle without a battery,
It has been proposed to provide a generator coil for driving a pump in a magnet generator attached to an engine, and drive the pump motor with the generator coil for driving the pump.

Further, noting that only the output of a half cycle of the ignition power supply coil provided in the magnet generator is used for supplying ignition energy , it is not used for supplying ignition energy of the ignition power supply coil. Attempts have been made to construct a DC power supply using the output of a half cycle, and drive an injector or an electronic device such as a microcomputer with the output of the DC power supply.

[0009]

To provide an exhaust characteristic-adjusting valve engine of a vehicle such as the battery is mounted [0008] by providing a power generation coil for driving valves for magneto generator mounted to the engine, it is conceivable to supply power to the actuator for Riva Lube driven by the said generating coil.

[0010] However, the magneto generator, it is necessary to supply power to the lighting load and the like, when the power generation coil for the ignition power supply coil and the pump drive on board magnet generator is already provided, further to Ba It is often difficult to provide a power generation coil for driving the lube. When stronger and it is intended to create the generating coil for driving valves, the magneto generator is large in size, it is large in size the engine on the cost becomes high.

An object of the present invention, when the battery is not mounted, the exhaust characteristic-adjusting without the valve exclusive generator coil specially provided, so that it is possible to drive both the fuel injector and valves It is another object of the present invention to provide a power supply device for driving auxiliary equipment of an internal combustion engine.

[0012]

SUMMARY OF THE INVENTION The present invention provides a pump motor for driving a fuel pump for supplying fuel to an injector and an exhaust characteristic adjusting valve for adjusting the characteristics of an exhaust system. The present invention relates to a power supply device for driving an auxiliary device of an internal combustion engine, which supplies electric power to an electric actuator for driving the electric motor.

According to the first aspect of the present invention, a common generator driving coil for both the pump motor and the actuator is provided in the magnet generator driven by the internal combustion engine. A drive power supply circuit is provided for supplying drive power to the pump motor and the actuator using the power generation coil as a power supply.

In the invention described in claim 2, the drive power supply circuit includes a pump drive switch for turning on / off a drive current of a pump motor, an actuator drive switch for turning on / off a drive current of an actuator, a pump drive switch, and an actuator drive. And a switch control device for conducting the switches at different duty ratios.

[0015]

When the fuel is supplied to the engine by the injector, a system for supplying the fuel from the electric pump to the injector in order to determine the fuel supply amount by the time for opening the valve of the injector (time for giving the injection command to the injector). Is provided with a pressure regulator to keep the pressure (fuel pressure) of the fuel supplied to the injector constant.

The discharge amount of the fuel pump driven by the motor is almost proportional to the drive torque of the motor, and the drive torque of the motor is proportional to the drive current of the motor. While the engine speed is low and the output of the magnet generator is low, the pump discharge pressure does not reach the value required to maintain the rated value of the fuel pressure (adjusted by the pressure regulator). Drive current increases as the rotational speed increases.
When the engine speed exceeds the set value, the discharge pressure of the pump tries to exceed the rated value of the fuel pressure.However, the fuel pressure is maintained at the rated value by the pressure regulator, so the discharge pressure of the pump is maintained at a constant value. Therefore, the driving current of the motor is limited to a constant value. Therefore, in the middle and high speed region of the engine, the output of the power generation coil becomes excessive, and the excess output is discarded.

On the other hand, the exhaust characteristic adjusting valve provided in the exhaust system is mostly operated only when the engine is running at a high speed. If possible.

Therefore, as in the present invention, an auxiliary machine driving power generating coil is provided in common for both the pump motor and the actuator, and the pump motor and the actuator are driven by the auxiliary machine driving power generating coil. In this case, in a low-speed region where it is not necessary to drive the exhaust characteristic adjusting valve, the output of the auxiliary device driving power generation coil is used exclusively for driving the pump motor, and the pump motor can be operated without any trouble. In the high speed range of the engine capable enough room in the output of the generating coil, without sacrificing the driving power of the pump motor, it is possible to supply driving power to the actuator for driving valves.

[0019] Thus, according to the present invention, for driving an actuator of the pump motor and valves for driving the common generating coil, a fuel pump with a small magnet generator and exhaust characteristic adjustment valve Can be driven without hindrance, and even when a battery is not mounted, the performance of the engine is improved by using the fuel injection device and the exhaust characteristic adjusting valve without using a large-sized magnet generator. be able to.

In particular, as in the invention described in claim 2,
When a pump drive switch for turning on / off the drive current of the pump motor and an actuator drive switch for turning on / off the drive current of the actuator are provided, and the pump drive switch and the actuator drive switch are controlled to conduct at different duty ratios, Since the output of the driving power generation coil can be accurately distributed to the pump motor and the actuator, the exhaust valve can be operated without impairing the operation of the pump motor even in a region where the rotational speed is relatively low.

[0021]

1 shows an overall configuration of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an internal combustion engine having an intake pipe 2 and an exhaust pipe 3; This is a magnet generator comprising a magnet rotor 4A provided and a stator 4B attached to an engine case.

A throttle valve 5 is mounted on the inlet side of the intake pipe 2, and an injector 6 is mounted so as to inject fuel into a space downstream of the throttle valve 5 in the intake pipe. The injector 6 includes a valve for opening and closing the injection port, and an electromagnet for operating the valve. The electromagnet is excited and the valve is opened while the injection command signal is given.

A fuel pump 7 comprises a pump motor (electric motor) 7A and a pump 7B driven by the motor. The suction port of the pump 7B is connected to a fuel tank 9 via a pipe 8.
, And a discharge port of the pump 7B is connected to a fuel supply port of the injector 6 via a pipe 10.

Reference numeral 11 denotes a pressure regulator connected between the fuel supply port of the injector 6 and the fuel tank 9. The pressure regulator regulates the pressure of the fuel supplied to the fuel supply port of the injector 6 to a set value. By returning a part of the fuel to the fuel tank 9 when it exceeds, the pressure (fuel pressure) of the fuel supplied to the injector 6 is kept constant.

When an injection command signal is given to the injector 6, the valve of the injector 6 opens, so that fuel is injected from the injection port into the intake pipe 2. The amount of fuel given to the engine is determined by the fuel pressure and the injection time. The time for giving the injection command signal to the injector 6 is controlled so that the mixed gas having the optimum air-fuel ratio is supplied into the cylinder of the engine at each rotation speed of the engine.

The exhaust pipe 3 is provided with a cavity 3A, and an exhaust characteristic adjusting valve 12 is provided so as to change an opening cross-sectional area of a pipe upstream of the cavity 3A. The exhaust characteristic adjusting valve 12 of the present embodiment includes:
Consist valve linear displacement shaped and out into the exhaust pipe to change the opening cross-sectional area of the exhaust pipe 3 from a direction perpendicular to the axial direction of the exhaust pipe 3, this valves are connected to 該Ba lube Rack 13, a pinion 14 meshed with the rack 13, and an electric motor 15 for rotationally driving the pinion 14.
And is driven by an actuator 16 composed of

The exhaust characteristic adjusting valve 12 need not be a linear displacement type, but may be a rotary type.

The exhaust characteristic adjusting valve 12 is provided to increase the exhaust efficiency of the engine by causing resonance in a cavity provided in the exhaust system when the engine is running at a high speed. It is operated by the actuator 16 so that the opening degree becomes an optimal size. FIG.
FIG. 9 shows an example of a change in the operating angle θ of the actuator 16 for operating the exhaust characteristic adjusting valve with respect to the rotational speed N. In the example shown by the solid line in FIG. 9, the set rotational speed Ns (> N)
2) In the above region, a drive current is applied to the actuator 16 to change the operating angle θ of the actuator from 0 to θ4 (0 <θ1).
<Θ2 <θ3 <θ4).
In the example shown in FIG. 9, the operation angle of the actuator is 0.
In the state, there opening degree of the exhaust gas characteristic-adjusting valve is in the lowest state, go opening degree of the exhaust gas characteristic-adjusting valve is increased according to the operation angle of the actuator becomes large.
By adjusting the opening degree of the exhaust gas characteristic-adjusting valve in the set rotational speed Ns or more areas, to increase the amount of gas flowing into the exhaust <br/> the trachea and the exhaust pipe to the resonance state, thereby supplying air Efficiency has been increased to improve engine output.

At each rotation speed, in order to control the opening of the exhaust characteristic adjusting valve to match the target opening, the exhaust
A position sensor for detecting the position of the characteristic-adjusting valve is provided, the actuator 16 so as to match the position of the valves, which are detected by the position sensor to the target position is controlled.

In the present invention, the auxiliary generator driving coil 4a common to the pump motor 7A and the actuator 16 is provided in the magnet generator 4, and the output of the auxiliary driving generator coil 4a is the driving power. It is supplied to the pump motor 7A and the actuator 16 via the supply circuit 17.

In the magnet generator 4, an ignition power supply coil for supplying ignition energy to the ignition device of the engine is provided in addition to the power generation coil 4a, and a power generation coil for driving a lighting load and the like as necessary. Is provided. The ignition power supply coil induces an AC voltage in synchronization with the rotation of the engine. Normally, only the output of the positive half cycle of the ignition power supply coil is used to supply ignition energy to the igniter, so a power supply circuit that generates a DC constant voltage using the output of the negative half cycle is configured. You. This power supply circuit is constituted by, for example, a power supply capacitor charged by the output of the negative half cycle of the ignition power supply coil, and a control circuit for keeping the voltage across the power supply capacitor at a constant value. This power supply circuit
In addition to being used as a power supply for a control circuit and a microcomputer for controlling the ignition timing and the fuel injection timing, it is also used as a power supply for giving an injection command signal to the injector 6.

FIG. 2 shows an example of the configuration of the driving power supply circuit 17. In this example, a connection is made between a full-wave rectifier 18 for rectifying the output of the auxiliary device driving coil 4a and an output terminal of the rectifier 18. A smoothing power supply capacitor 19, and a voltage regulator 20 for controlling the voltage across the capacitor 19 to be less than the rated voltage V1 of the pump motor. 7A and the actuator 16.

When the voltage at both ends of the capacitor 19 exceeds the rated value, the voltage regulator 20 short-circuits the power generation coil 4a to reduce the output voltage of the power generation coil 4a.
9 when the voltage between both ends becomes lower than the rated value.
The circuit comprises a circuit for recovering the output voltage of the power generation coil 4a by releasing the short circuit of a, and controls the output voltage of the power generation coil 4a so as to limit the voltage between both ends of the capacitor 19 to a rated value or less.

The output characteristics of the magnet generator 4 are, for example, as shown by curves N1 to N4 in FIG. Curves N1 to N in FIG.
4 indicates that the engine speed is N1 to N4 (N1 <N2 <
This shows the characteristics of the output voltage V versus the load current I when N3 <N4). A straight line L in FIG. 8 indicates a load characteristic of the pump motor. In FIG. 8, I1 is the rated current of the pump motor determined by the adjustment value of the pressure regulator 11, and when the drive current of the pump motor reaches the rated current I1, the discharge pressure of the pump reaches the adjustment value of the pressure regulator. .

The drive current of the pump motor 7A increases as the rotational speed N increases, as shown by the curve A in FIG. In FIG. 10, the curve B shows the load current versus rotation speed characteristics when the auxiliary drive generating coil 4a generates the rated voltage V1 of the pump motor.

When the number of revolutions exceeds N1, the drive current of the pump motor can reach the rated current I1. When the drive current of the pump motor exceeds the rated value I1,
The discharge pressure of the pump will overcome the pressure adjustment value of the pressure regulator, but if the discharge pressure of the pump exceeds the adjustment value of the pressure regulator, the pressure will be adjusted by the pressure regulator, and the discharge pressure of the pump will increase. As a result, the load torque of the pump motor eventually becomes constant, and the drive current is maintained at the rated current I1 even when the rotational speed increases. The voltage applied to the pump motor increases as the number of revolutions increases, and when the number of revolutions reaches N2, the voltage applied to the pump motor reaches the rated voltage V1. If the voltage regulator 20 is not provided, the voltage applied to the pump motor when the rotation speed increases to N4 becomes V2 (see FIG. 8).

In this embodiment, the power generation coil 4 is controlled so that the voltage across the power supply capacitor 19 is limited to the rated value V1 or less.
Since the voltage regulator 20 for adjusting the output voltage a is provided, the voltage applied to the pump motor is maintained at V1. When the voltage is limited to V1 and the number of revolutions rises to N4, a current I2 can flow from the generator coil 4a to the load as shown in FIG. 8, but in reality, the pressure regulator 11 is provided. As a result, the drive current of the pump motor is limited to the rated value I1, and when the generator coil 4a loads only the pump motor, when the engine speed rises to N4, V1.times. The power of (I2 -I1) is wastefully consumed and discarded by the voltage regulator 20. When the generator coil 4a uses only the pump motor 7A as a load, a current in a range shown by hatching in FIG. 10 can be supplied to other loads in a medium-high speed rotation region where the engine speed exceeds N2.

In the present invention, the actuator 16 is used by utilizing the surplus power generated in the region exceeding the rotation speed N2.
To drive the pump motor 7A and the actuator 1
6 can be driven by the common auxiliary drive power generating coil 4a.

FIG. 3 shows another embodiment of the present invention. In this embodiment, a switch circuit for selectively supplying a current supplied from a power generating coil 4a through a rectifier 18 to a pump motor 7A and an actuator 16 is shown. 21 and a switch control means 22 for controlling the switch circuit 21 are provided. The switch circuit 21 includes a pump drive switch 21A that turns on and off a drive current of the pump motor,
An actuator drive switch 21B for turning on and off the drive current of the actuator is provided. The switch control means 22 sets the pump drive switch 21A and the actuator drive switch 21B to different duty ratios D
Control is performed so that conduction is performed alternately at p and Da.

Here, the duty ratio D is given by D when the ON period of the switch means is Ton and the OFF period is Toff.
= Ton / (Ton + Toff), and Dp + Da = 1
There is a relationship.

With this configuration, the output of the auxiliary drive power generating coil 4a is connected to the pump motor 7A and the actuator 1
6, the actuator 16 can be operated without impairing the operation of the pump motor 7A even in a region where the number of revolutions is relatively low, and as shown by a broken line in FIG. It is also possible to start the operation of the actuator 16 at a set speed Ns' lower than the speed N2 at which the voltage applied to the pump motor reaches the rated value V1.

FIG. 4 shows an embodiment in which each part of FIG. 3 is concretely shown. In the switch circuit 21 of the embodiment shown in FIG. 4, the pump drive switch 21A is constituted by the transistors Tr1 and Tr2 and the resistors R1 and R2, and the actuator drive switch 21B is constituted by the transistors Tr3 to Tr5 and the resistors R3 to R5. Have been. Reference numeral 21a denotes a control terminal of the switch circuit. When a high-level trigger signal is applied to this control terminal, the transistors Tr2 and Tr5 are turned on and the transistor Tr4 is turned off. At this time, the transistor Tr1 is turned on and the transistor Tr3 is turned off.
A is supplied with a drive current.

When the trigger signal is removed from the control terminal 21a and the potential of the control terminal becomes low, the transistors Tr2 and Tr5 are turned off, and the transistor T2 is turned off.
r4 becomes conductive. At this time, the transistor Tr1 is turned off, the transistor Tr3 is turned on, and the drive current is supplied to the actuator 16.

In this embodiment, four reluctors (inductors) 401 are formed at equal angular intervals on the outer periphery of a cup-shaped yoke (flywheel) 400 of a magnet rotor 4A of a magnet generator 4, and a signal generating rotor is formed. SR and the rotor S
The signal emission SG is opposed to the outer periphery of R. The signal generator SG has a known inductor type including a core having a magnetic pole portion facing the outer periphery of the rotor SR, a signal coil wound around the core, and a magnet magnetically coupled to the core. With the electrons, pulse signals Vp1 and Vp2 having different polarities are respectively applied to the signal coils when the reluctor 401 starts facing the magnetic pole portion of the signal emission SG and when the reluctor 401 finishes facing the magnetic pole of the signal emission SG. Induce. These pulse-like signals are supplied to a waveform shaping circuit 23, which shapes the waveform of the pulse-like signal Vp1 having one polarity to generate four pulse signals Vp per rotation.

The pulse signal Vp is applied to a frequency-voltage converter 24, which converts the frequency of the pulse signal Vp into a voltage signal Vn '. This voltage signal Vn 'is proportional to the engine speed. The output voltage Vn 'of the frequency-voltage conversion circuit is input to an inverting input terminal of a comparator 27 through a voltage limiting circuit 25 composed of a Zener diode or the like.

A triangular wave signal generator 26 is provided,
An output of the triangular wave signal generator 26 is input to a non-inverting input terminal of a comparator 27, and an output terminal of the comparator 27 is connected to a control terminal 21a of the switch circuit 21.

In this embodiment, the signal generating rotor SR and
The switch control means 22 is composed of the signal emission SG, the waveform shaping circuit 23, the frequency-voltage conversion circuit 24, the voltage limiting circuit 25, the comparator 27, and the triangular wave signal generator 26. The power sources of the waveform shaping circuit 23, the frequency / voltage converting circuit 24, the voltage limiting circuit 25, the comparator 27 and the triangular wave signal generator 26 may be supplied from the output side of the rectifier 18, and use the output of the negative half cycle of the ignition power supply coil. It may be obtained from a power supply circuit.

In the embodiment shown in FIG. 4, the output voltage Vn 'of the frequency-to-voltage converter 24 increases linearly as the rotational speed N increases. The maximum value of the voltage Vn 'is limited by the voltage limiting circuit 25. Therefore, the inverting input terminal of the comparator 27 has a rotation speed detection signal V as shown in FIG.
n is entered. The signal Vn rises linearly with the rise of the rotational speed N, reaches the set value Vn1 at the set rotational speed Ns' shown in FIG. 9, and reaches the limit value Vn2 at the set rotational speed Ns. In the region exceeding the set rotation speed Ns, the rotation speed detection signal V
n maintains a constant value Vn2.

As shown in FIG. 6A, the triangular wave signal generator 26 generates a triangular wave signal Vs on which a DC bias voltage equal to the set value Vn1 is superimposed. The comparator 27
The rotation speed detection signal Vn is compared with the triangular wave signal Vs, and the potential of the output terminal is set to a high level while the triangular wave signal Vs exceeds the rotation speed detection signal Vn. While the rotation speed of the engine is low, the rotation speed detection signal Vn cannot exceed the triangular wave signal Vs, so the potential Vt of the output terminal of the comparator 27 is kept at a high level. At this time, the transistors Tr2 and Tr5 are turned on and the transistor Tr4 is turned off, so that the transistor Tr1 (the pump drive switch 21A) is turned on and the transistor Tr3 (the actuator drive switch 21B) is turned off. In this state, the duty ratio Dp of the ON operation of the transistor Tr1 becomes 1, and the drive current is supplied only to the pump motor 7A.

When the engine speed exceeds the set speed Ns',
When the rotation speed detection signal Vn exceeds the set value Vn1, the rotation speed detection signal Vn can exceed the triangular wave signal Vs, and the period during which the triangular wave signal Vs exceeds the rotation speed detection signal Vn and the rotation speed detection signal The period in which the signal Vn exceeds the triangular wave signal Vs alternately occurs. During the period when the triangular wave signal Vs exceeds the rotation speed detection signal Vn, the potential of the output terminal of the comparator 27 is at a high level, so that the transistor Tr1 conducts and the transistor T
r3 shuts off. On the other hand, during the period in which the rotation speed detection signal Vn exceeds the triangular wave signal Vs, the potential of the output terminal of the comparator 27 is at a low level.
r5 is turned off, and the transistor Tr4 is turned on. At this time, since the transistor Tr1 is turned off and the transistor Tr3 (actuator drive switch) is turned on, the drive current Ia is supplied to the actuator 16 through the transistor Tr3. Therefore, when the number of rotations exceeds the set number of revolutions Ns', the transistors Tr1 and Tr3 are alternately turned on to supply a drive current to the pump motor 7A and the actuator 16 alternately. Transistor Tr3
The duty ratio Da of the ON operation increases with an increase in the rotational speed. When the rotational speed reaches the set rotational speed Ns, the increase in the duty ratio Da stops.

FIG. 6B shows the waveform of the potential Vt at the output terminal of the comparator 27 when the rotation speed detection signal Vn has reached the limit value Vn2, and FIGS. 6C and 6D show the waveform. Drive current I supplied to the pump motor and the actuator, respectively
p and Ia are shown.

First in a high-speed region exceeding the set rotation speed Ns
The magnitudes of the duty ratios Dp and Da of the ON operation of the actuator drive switch can be appropriately changed by adjusting the limit value Vn2 of the rotation speed detection signal Vn.

As described above, according to the embodiment shown in FIG. 4, the pump drive switch 21A and the actuator drive switch 21B alternately conduct at a predetermined duty ratio to alternately supply a current to the pump motor 7A and the actuator 16. Since power is supplied, power can be distributed to the pump motor and the actuator at an appropriate ratio by appropriately setting the duty ratio of each switch.

According to the embodiment shown in FIG. 4, the pump drive switch and the actuator drive switch are alternately made conductive at a predetermined duty ratio in a region equal to or higher than the set rotation speed Ns', so that the pump motor and the actuator are connected to each other. The drive current can be supplied alternately. In this case, the current that can be supplied to the actuator by the on / off control of the pump drive switch and the actuator drive switch is a current in a range indicated by hatching in FIG. In FIG. 11, a curve A shows the drive current versus rotation speed characteristic of the pump motor 7A, and a curve B shows the load current versus the rotation speed when the auxiliary drive generating coil 4a generates the rated voltage V1 of the pump motor. It is a characteristic.

In the above embodiment, the switch control means is realized by an electronic circuit. However, the switch control means can be realized by using a microcomputer. FIG. 7 is a flowchart showing an algorithm of the control means when the switch control means is realized by a microcomputer.
It was shown to.

When following this flowchart, first, the pump drive switch 21A is closed, and the engine speed is calculated. The number of revolutions of the engine can be obtained, for example, from the generation cycle of a signal output from a signal generator attached to the internal combustion engine. After calculating the rotation speed of the engine, the speed exhaust Patent
It is determined whether or not the number of rotations is at which the sex adjustment valve is operated. To make this determination, the engine speed to move the exhaust characteristic-adjusting valve, in the form of a map in advance and the displacement amount of the valves RO
M may be stored in, by referring to the map when the rotational speed is computed, it determines whether it is necessary to move the rotational speed Device Lube. As a result, when it is necessary to operate the exhaust characteristic adjusting valve at the calculated rotational speed, the drive power of the pump motor required to obtain a predetermined fuel pressure at the rotational speed and the exhaust characteristic adjusting valve And the drive power of the actuator required to move the actuator by a specified amount of displacement at the rotation speed.

Next, the duty ratio Dp of the pump drive switch required to obtain the calculated drive power of the pump motor and the duty ratio Da of the actuator drive switch required to obtain the calculated drive power of the actuator are calculated. Then, the pump drive switch and the actuator drive switch are turned on alternately at duty ratios Dp and Da, respectively.

[0058] Then by monitoring the output of the sensor for detecting the position of the exhaust characteristic-adjusting valve, and an actuator drive switch a cutoff state when the the movement of the valves is completed is confirmed, returns to the start.

In the above embodiment, the pump drive switch and the actuator drive switch are alternately turned on. However, both switches may be turned on and off independently at a predetermined duty ratio.

[0060]

As described above, according to the present invention, a generator coil for driving auxiliary equipment is provided in common for both the pump motor and the actuator for driving the valve, and the generator coil for driving auxiliary equipment is used. Since the pump motor and the actuator are driven, in the low-speed region where it is not necessary to drive the exhaust characteristic adjusting valve, the output of the auxiliary drive power generating coil is used exclusively for driving the pump motor, and the pump motor is driven. can be operated without any trouble, and in the high speed range of the engine capable enough room in the output of the generating coil, without sacrificing the driving power of the pump motor, to supply driving power to the actuator for driving valves Can be.

[0061] Therefore, according to the present invention, the pump motor
Valves can an actuator for driving be driven by a common generating coil, there is an advantage that both the can drive without hindrance between the fuel pump and the exhaust characteristic adjustment valve with a small magnet generator.

In particular, according to the invention described in claim 2,
A pump drive switch for turning on / off the drive current of the pump motor and an actuator drive switch for turning on / off the drive current of the actuator are provided, and the pump drive switch and the actuator drive switch are controlled so as to conduct at different duty ratios. The output of the generator coil for machine drive can be accurately distributed between the pump motor and the actuator, and the exhaust characteristics can be maintained without impairing the operation of the pump motor even in the region where the rotational speed is relatively low.
There is an advantage that the adjusting valve can be operated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration example of a driving power supply circuit used in an embodiment of the present invention.

FIG. 3 is a circuit diagram showing another configuration example of the driving power supply circuit used in the embodiment of the present invention.

FIG. 4 is a circuit diagram showing an embodiment in which each part of the embodiment of FIG. 3 is made concrete;

FIG. 5 is a diagram showing a change with respect to the rotation speed of a rotation speed detection signal used in the embodiment of FIG. 4;

6 (A) to 6 (D) are waveform diagrams showing signal waveforms of respective parts in the embodiment of FIG. 4;

FIG. 7 is a flowchart showing an algorithm when the switch control means is realized by a microcomputer.

FIG. 8 is a diagram showing an example of an output voltage-output current characteristic of a magnet generator.

FIG. 9 is a diagram showing an example of the operation characteristics of the exhaust characteristic adjusting valve.

FIG. 10 shows a range in which the actuator can be driven when the drive power supply circuit of FIG. 2 is used. The drive current versus rotation speed characteristics of the fuel pump and the output voltage of the auxiliary drive generator coil generate the rated voltage of the pump motor. FIG. 5 is a diagram showing the relationship between the load current and the rotation speed characteristics when the motor is operating.

FIG. 11 shows an area in which the actuator can be driven when the drive power supply circuit of FIG. 3 is used. The drive current vs. rotation speed characteristic of the fuel pump and the output voltage of the auxiliary drive generator coil generate the rated voltage of the pump motor. FIG. 5 is a diagram showing the relationship between the load current and the rotation speed characteristics when the motor is operating.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Intake pipe 3 Exhaust pipe 4 Magnet generator 5 Throttle valve 6 Injector 7 Fuel pump 7A Pump motor 7B Pump 11 Pressure regulator 12 Exhaust characteristic adjustment valve 16 Actuator 17 Drive power supply circuit 21 Switch circuit 21A Pump drive switch 21B Actuator drive switch 22 Switch control means

Claims (2)

(57) [Claims] A pump motor for driving a fuel pump for supplying fuel to an injector, and an electric actuator for driving an exhaust characteristic adjusting valve for adjusting characteristics of an exhaust system, among auxiliary equipment provided in the internal combustion engine. A power supply device for driving an accessory of an internal combustion engine, which supplies power to the internal combustion engine, wherein a power generating coil for driving an accessory is provided commonly to both the pump motor and the actuator in a magnet generator driven by the internal combustion engine. And a drive power supply circuit for supplying drive power to the pump motor and the actuator, respectively, using the auxiliary drive power generating coil as a power supply, and an auxiliary drive power supply device for an internal combustion engine. 2. The driving power supply circuit, comprising: a pump driving switch for turning on and off a driving current of the pump motor;
The internal combustion engine according to claim 1, further comprising: an actuator drive switch for turning on / off the drive current of the actuator; and a switch control device for turning on the pump drive switch and the actuator drive switch at different duty ratios. Auxiliary equipment drive power supply.