JP2959234B2 - Operating method of AC generator for fuel injection type 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 method for operating an alternator mounted on a fuel injection type internal combustion engine.

[0002]

2. Description of the Related Art A fuel injection device for a gasoline engine includes an injector having a valve operated by an electromagnet or the like, a fuel pump for supplying fuel to the injector, and a constant pressure (fuel pressure) of fuel supplied to the injector. And a pressure regulator for controlling the pressure, and when a fuel injection command is given, the valve of the injector is opened to inject the fuel.

In order to operate this fuel injection device,
During the operation of the engine, it is necessary to drive the fuel pump to supply fuel to the injector at all times.In order to start the engine without hindrance, a sufficient amount of fuel must be supplied from the fuel pump even when the engine is started. Must be discharged. The pump motor that drives the fuel pump is a DC motor, and is driven by a battery that is charged through a rectifier circuit by an AC generator mounted on the engine.

[0004] A power supply device generally provided in an internal combustion engine includes:
It consists of an AC generator driven by the engine and a battery that is charged through the rectifier circuit with the output of the AC generator, and cannot output a large output from the generator. At a medium speed and a high speed at which power is supplied to the load and the generator generates a sufficient output, power is supplied to the load while charging the battery with the output of the generator.

FIG. 8 shows an example of a power supply device used in a fuel injection type internal combustion engine. In the figure, 1 'is a magnet type alternator attached to an internal combustion engine,
This generator has a power generating coil W1, and an AC output voltage obtained from the power generating coil W1 is input to a rectifier circuit 2 including bridge-connected diodes D1 to D4. A battery 3 is connected between output terminals of the rectifier circuit 2, and a pump motor 5 is connected to both ends of the battery 3 via a switch 4. Reference numeral 6 denotes a fuel tank, 7 denotes an injector, and the fuel in the fuel tank 6 is supplied to the injector 7 by a fuel pump driven by a pump motor 5. Reference numeral 8 denotes a pressure regulator for controlling the pressure (fuel pressure) of the fuel supplied from the fuel pump to the injector 7 to be constant.
When the fuel pressure becomes excessive, a part of the fuel supplied from the fuel pump is returned to the fuel tank 6 to keep the fuel pressure constant. 9
Is another load connected to both ends of the battery.

In some cases, a regulator for controlling the charging voltage of the battery not to be excessive may be further provided. This regulator includes, for example, a detector that detects a voltage across the battery, and a circuit that limits the voltage applied to the battery when the value detected by the detector exceeds a set value. If the generator is a magnet generator,
As a circuit for limiting the voltage applied to the battery, when the voltage across the battery exceeds a set value, the power generation coil W
A circuit that shorts 1 is often used. In some cases, a control rectifier circuit including a thyristor is used as the rectifier circuit 2, and the voltage applied to the battery is controlled by controlling the firing phase of the thyristor according to the voltage across the battery. Further, a control element such as a transistor that can control the internal resistance is inserted between the rectifier circuit 2 and the battery, and the voltage applied to the battery is controlled by controlling the internal resistance of the control element according to the output voltage. It may be kept below the set value.

[0007]

In the generator shown in FIG. 8, since the rise of the voltage induced in the power generation coil W1 is slow after the start of the generator, a sufficient output for driving the load at low speed rotation is obtained. Cannot occur. Therefore, in the conventional generator, the battery must be driven for driving the load at the time of starting the engine or at a low speed, and the pump motor is driven when the battery goes up or the battery is removed due to theft or the like. And the engine cannot be started. In particular, when such a situation occurs in the outboard motor, it is impossible to return to the port, which is dangerous. In order to solve the above problem, it is conceivable to increase the capacity of the alternator so that the load can be driven without a battery, but recently, in order to save fuel consumption by reducing the weight of the engine. Since it is required to make the generator as small as possible, it is difficult to increase the capacity of the generator. An object of the present invention is to provide a method of operating an AC generator for a fuel injection type internal combustion engine that can normally drive a pump motor even when a battery cannot be used without using a large generator. is there.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a power generation system in which the output voltage of an AC generator mounted on a fuel injection type internal combustion engine is supplied to a load including a pump motor of a fuel injection device for an internal combustion engine through a rectifier circuit. It relates to the operation method of the machine. In the present invention, a plurality of generating coils are provided in the AC generator, and the plurality of generating coils are connected in series or in parallel according to the state of the load to operate the generator, so that when the engine is running at a low speed. From time to high speed, the load including the fuel pump is driven without any trouble.

The invention described in claim 1 is applied to a case where the load includes a battery. In the present invention, when the battery is in a state where it can be used normally,
When the alternator is operated by connecting a plurality of generating coils in parallel and the battery is in a state where the battery is raised or removed and is not in a state where it can be used normally, the plurality of generating coils are connected in series. To operate the alternator. The inventions described in claims 2 to 4 are applicable regardless of whether or not a battery is provided. In the invention described in claim 2, a load current flowing when a plurality of power generation coils are connected in series and a load current flowing when a plurality of power generation coils are connected in parallel are actually detected,
The magnitude of the detected both load currents is discriminated , and the alternator is operated by connecting a plurality of power generation coils in the connection method of the one having the larger detected load current. ◎ In the invention described in claim 3, while detecting the voltage applied to the load,
A load current that flows when a plurality of power generation coils are connected in series and a load current that flows when a plurality of power generation coils are connected in parallel are actually detected to determine the magnitude of the detected load currents. When the voltage applied to the load is equal to or less than the set value, the detected load current is connected to a plurality of power generating coils in the connection method of the larger one, and when the voltage applied to the load exceeds the set value, The AC generator is operated by connecting a plurality of power generation coils in a connection method that reduces the voltage applied to the AC generator. In the invention described in claim 4, a voltage supplied to the load when a plurality of power generation coils are connected in series and a voltage supplied to the load when the plurality of power generation coils are connected in parallel are actually detected. The voltage supplied to the load when a plurality of power generation coils are connected in series and the voltage supplied to the load when a plurality of power generation coils are connected in parallel are determined. When it is detected that the voltage is equal to or less than the set value, the generator is operated by connecting a plurality of power generation coils in a connection method in which the voltage supplied to the load is higher. It was also detected that either the voltage supplied to the load when a plurality of power generation coils were connected in series or the voltage supplied to the load when a plurality of power generation coils were connected in parallel exceeded a set value . At times, the generator is operated by connecting a plurality of generating coils in a manner of connection having a lower voltage supplied to the load. The rectifier circuit can be provided in common for a plurality of power generation coils. In this case, switching between the series connection and the parallel connection of the plurality of power generation coils is performed on the input side of the rectifier circuit. In the case of such a configuration, it is necessary that a plurality of power generating coils generate an AC output having the same phase. Further, the rectifier circuit may be provided for each of the plurality of power generation coils. In this case, a plurality of power generating coils are connected between input terminals of the corresponding rectifier circuits, and switching between the serial connection and the parallel connection of the plurality of power generator coils is performed on the output side of the rectifier circuit. In such a configuration, the plurality of power generation coils may generate AC outputs having different phases.

[0010]

When a plurality of power generating coils provided in an AC generator are connected in series, the output voltage can be quickly raised after the generator is started, but the rise of the output voltage during high-speed rotation is suppressed. When a plurality of power generation coils are connected in parallel, the output voltage rises slowly, but the output voltage during high-speed rotation increases. Therefore, if a plurality of power generating coils are connected in series, a relatively high output voltage can be obtained even when the engine is started and at low speed, so that the fuel pump can be used even at the time of starting the engine and at low speed. It is possible to drive a load including the battery, and the engine can be operated even when the battery goes up or the battery is removed. When the battery is raised, the internal resistance is very large, and the charging current flowing when a voltage is applied to the battery is small (when the battery is raised, the charging voltage is not applied. However, since the chemical reaction does not proceed immediately inside), most of the output current of the power generation coil flows to the fuel pump side. Therefore, even when the battery is running up, the fuel pump can be driven without any trouble. If a plurality of power generation coils are connected in series, an increase in the output voltage at high speed is suppressed, so that the voltage applied to the load does not become excessive when the battery is removed. On the other hand, when the battery is connected and is in a state where it can be used normally, if a plurality of power generation coils are connected in series, an increase in the output voltage at high speed is suppressed, and the charging current of the battery is insufficient. Become a trend. Therefore, when the battery can be used normally, it is better to connect a plurality of power generating coils in parallel in order to suppress a decrease in output at high speed. If a plurality of power generating coils are connected in parallel, the rise of the output voltage will be slow, but at low speed the fuel pump can be driven by the battery, so that there is no hindrance to the operation of the engine. Further, when the connection of the power generation coil is switched so that a large load current always flows, a large current is supplied to the pump motor even at a low speed when the battery cannot be used. Can be started, and at a high speed, a current required for obtaining a predetermined fuel pressure can be supplied to the pump motor. Therefore, even when the battery cannot be used, the engine can be operated without any trouble. When the battery can be used, a sufficient charging current can be supplied to the battery from a low speed to a high speed. Claim 3
When the load voltage is equal to or less than the set value, the generator coil is connected in the connection method in which the load current flows larger, and when the load voltage exceeds the set value, the load voltage decreases. If the power generation coil is connected by the connection method, a sufficient current can be supplied to the pump motor and the battery while preventing an excessive voltage from being applied to the pump motor and the battery. Further, even when the connection of the power generation coil is switched based only on the load voltage, the voltage applied to the battery or the pump motor can be prevented from being excessive, and the pump motor can be prevented from becoming excessive. And sufficient current can be supplied to the battery. According to the fifth aspect of the present invention, only one rectifying circuit needs to be provided, so that the circuit configuration can be simplified. In addition, with the configuration as in the invention described in claim 6, since the phases of the voltages output by the plurality of power generation coils may be different from each other, the present invention can be applied regardless of the configuration of the generator. it can.

[0011]

1 shows an example of the configuration of a power supply device used in the operation method of the present invention. In FIG. 1, reference numeral 1 denotes a magnet type alternator mounted on an internal combustion engine, 2 denotes a full-wave rectifier, and 3 denotes a full-wave rectifier. A battery, 4 is a switch that is closed when the engine is started, 5 is a pump motor, 6 is a fuel tank, 7 is an injector, 8
Is a pressure regulator, and 9 is any other load. Of these, the portions other than the generator 1 are the same as the conventional one described with reference to FIG.

The generator 1 has a plurality of (two in the illustrated example) power generating coils W1 and W2, and these power generating coils induce a single-phase AC voltage having the same phase in synchronization with the rotation of the engine. The power generating coils W1 and W2 are connected in series or in parallel by a changeover switch 10 and are connected between input terminals of the rectifier circuit 2. The changeover switch 10 comprises movable contacts 10a and 10b which are operated simultaneously, fixed contacts Sa and Pa to which the movable contact 10a is switched and connected, and fixed contacts Sb and Pb to which the movable contact 10b is switched and connected. Sb is a play contact. One end of the generating coil W1 is connected to one input terminal of the rectifier circuit 2 and the fixed contact Pa of the changeover switch, and the other end is fixed contact Sa of the changeover switch.
And the movable contact 10b. Generating coil W1
Is connected to the movable contact 10a of the changeover switch, and the other end is connected to the other input terminal of the rectifier circuit 2 and the fixed contact Pb. When the movable contacts 10a and 10b of the changeover switch 10 are brought into contact with the fixed contacts Sa and Sb, respectively, the power generating coils W1 and W2 are connected in series between the input terminals of the rectifier circuit 2, and the movable contacts 10a and 10b of the changeover switch are respectively connected. When they are brought into contact with the fixed contacts Pa and Pb, the power generating coils W1 and W2
Are connected in parallel between the input terminals of the rectifier circuit 2.

In the magnet type AC power generation, the characteristics of the output voltage V versus the load current I when two power generation coils W1 and W2 are connected in series are as shown by curves a to e in FIG. Here, the curves a to e have rotation speeds (rpm) of No to N, respectively.
4 (No <N1 <N2 <N3 <N4). The characteristics of the output voltage V vs. the load current I when the two power generation coils W1 and W2 are connected in parallel are shown as follows.
In the case of o to N4, curves a 'in FIG.
~ E '. Here, No is the starting rotational speed of the engine, and N4 is the maximum operating rotational speed of the engine. FIG. 2 shows a characteristic in a case where the number of revolutions of the generator is increased in a state where the fuel is not injected from the injector 7.

A broken line R indicated by a chain line in FIG. 2 is a load line of the pump motor. As the number of revolutions of the generator increases, the armature current of the pump motor increases with the increase in power generation output as the number of revolutions increases, and its output torque increases. The pump motor is locked (stopped because the motor cannot rotate) until the output torque necessary to discharge fuel from the pump at a pressure equal to or higher than the pressure set in the heater 8 is obtained from the motor. The load resistance of the pump motor indicates a value according to the internal resistance of the motor. After the torque given to the pump from the pump motor reaches a value at which fuel can be discharged from the pump at a pressure higher than the pressure set by the pressure regulator 8 (necessary for discharging the fuel from the pump at a pressure higher than the set pressure). (After the armature current Ir flows when the motor generates a large torque), the pump motor rotates, and the voltage across the pump motor rises to a voltage value that overcomes the back electromotive force. Since the fuel pressure is controlled to be constant (to maintain the set pressure) by the pressure regulator, the armature current of the pump motor is kept constant (= Ir). When the engine is actually started, the injector injects fuel, so that the fuel pressure applied to the injector drops to a value lower than the pressure set by the pressure regulator. Therefore, actually, the pump motor rotates before the armature current Ir shown in FIG. 2 flows, thereby discharging the fuel from the pump, and trying to recover the fuel pressure given to the injector to the set pressure. . In order to improve the startability of the engine, it is necessary to restore the fuel pressure given to the injector to the set pressure as soon as possible. It is preferable to make the rise of the current flowing through the pump motor faster.

In FIG. 2, Ipo indicates the armature current of the pump motor when the generator coils W1 and W2 are connected in parallel at the starting rotational speed No and Iso indicates the generator coils W1 and W2 at the starting rotational speed No. The figure shows the armature current of the pump motor when connected and operated in series. Vp4 indicates the voltage across the pump motor when the generator coils W1 and W2 are connected in parallel at the maximum engine speed N4, and Vs4 indicates the generator coil at the maximum engine speed N4. It shows the voltage across the pump motor when W1 and W2 are connected in series and operated. Also Ich
Indicates a desired charging current of the battery.

From the characteristics shown in FIG. 2, when the two generating coils W1 and W2 are connected in series to drive the pump motor, the characteristics of the voltage Vs at both ends of the motor and the armature current Is with respect to the rotation speed N and the two power generating coils W1 and W2 are shown. FIG. 3 shows the characteristics of the voltage Vp at both ends of the motor and the armature current Ip with respect to the rotation speed N when the pump motor is operated with the coils W1 and W2 connected in parallel. From this, the power generation coil W
It can be seen that the voltage rises faster and the current flowing through the pump motor rises faster when 1 and W2 are connected in series. Therefore, when the battery cannot be used, when the generator is operated by connecting the generator coils W1 and W2 in series, a high fuel pressure can be obtained even at a low rotational speed when starting with a recoil starter or the like, and Starting can be facilitated.

The characteristic of the charging current Isch with respect to the rotation speed N when the battery 3 is charged by connecting the generating coils W1 and W2 in series, and the charging current when the battery is charged by connecting both the generating coils in parallel. FIG. 4 shows the characteristics of Ipch with respect to the rotation speed N. In FIG. 4, VB indicates the voltage across the battery 3.

When the engine starts and the number of revolutions increases,
After the armature current of the pump motor reaches the set value Ir,
The voltage increases both when the power generating coils W1 and W2 are connected in series and when they are connected in parallel. However, when the engine speed exceeds N2, the voltage is higher when the power generating coils W1 and W2 are connected in parallel. And the maximum operating speed N of the engine
In the vicinity of 4, the voltage is much higher when the generator coils are connected in parallel than when they are connected in series. Since it is not desirable to apply a voltage significantly higher than the rated voltage to the pump motor, if the battery cannot be used after all and the pump motor is driven only by the generator, the generator coils W1 and W2 are connected in series. It is more advantageous to do so.

On the other hand, when the battery is in a state where it can be used normally, it is necessary to operate the power generating coils W1 and W2 in parallel in order to supply a desired charging current Ich. In this case, the output voltage of the generator is insufficient at low speed, but there is no problem at low speed because the fuel pump can be driven by the battery.

That is, in the embodiment of FIG. 1, when the battery is in a state where it can be used normally, the changeover switch 1
The generator is operated with the 0 movable contacts 10a and 10b brought into contact with the fixed contacts Pa and Pb and the power generating coils W1 and W2 connected in parallel.

When the battery 3 rises, the generator is operated in a state where the movable coils 10a and 10b of the changeover switch 10 are brought into contact with the fixed contacts Sa and Sb, respectively, and the generating coils W1 and W2 are connected in series. I do. In this case, it is preferable that the load 9 be separated from the circuit in order to prevent the power from being supplied to the fuel pump due to the power being supplied to the load 9.

In the above embodiment, the connection of the power generation coils W1 and W2 is connected in parallel or in series depending on whether the battery can be used or not. However, by detecting the load current, the connection can be made regardless of the presence or absence of the battery. In addition, it is possible to make the operation more detailed.

FIG. 5 shows a state in which the load current is detected and the power generation coil W is detected.
1 and W2 are switched. In this example, a changeover switch 10 'formed of an electromagnetic relay is used to switch and connect the power generation coil W1 in series and parallel.
The movable contact and the fixed contact of the relay 10 'are denoted by the same reference numerals as those of the changeover switch of the embodiment of FIG. 1. When the relay is not excited, the movable contacts 10a and 10b contact the fixed contacts Pa and Pb, respectively. Generating coils W1 and W2
Are connected in parallel. In this example, a current detector 11 is inserted between the rectifier 2 and the load, and a detection output of the current detector is input to a control device 12 that controls the relay 10.

The control device 12 periodically excites the relay for a short period of time, and the magnitude of the load current flowing when the generating coils W1 and W2 are connected in parallel (the magnitude of the load current immediately before the relay is excited). And the magnitude of the load current flowing when the generating coils W1 and W2 are connected in series,
The generating coils W1, W1
2 to control the excitation of the relay 10 '.
That is, when the load current when the power generation coils W1 and W2 are connected in series is larger than the load current when the power generation coils W1 and W2 are connected in parallel, the relay 10 'is energized and its movable contacts 10a, 10b are brought into contact with the fixed contacts Sa and Sb, respectively, and the power generating coils W1 and W2 are connected in series. When the load current when the generating coils W1 and W2 are connected in parallel is larger than the load current when the generating coils W1 and W2 are connected in series, the relay 1
0 'is de-energized and its movable contacts 10a, 10b are brought into contact with the fixed contacts Pa, Pb, respectively, and the power generating coils W1,
W2 is connected in parallel. Thus, the power generation coils W1,
The magnitude of the load current when W2 is connected in series and the magnitude of the load current when connected in parallel are discriminated, and the generator is operated by connecting the generating coil in the connection method with the larger load current. If the battery cannot be used, the armature current Is flows from point A to point B in FIG.
The armature current Ip flows from the point B to the point C, so that a sufficient armature current can be supplied to the pump motor even at the time of starting the engine to obtain a sufficient fuel pressure. When a battery is connected, the charging current Isch flows from the point D to the point E in FIG.
Flows, so that charging can be started at a low rotation speed and a large charging current can flow.

The magnitude of the load current flowing when the generating coils W1 and W2 are connected in parallel as described above is compared with the magnitude of the load current flowing when the generating coils W1 and W2 are connected in series. When the load is driven by connecting the generating coils W1 and W2 in the connection method with the larger load current, it is preferable that the load 9 is separated from the circuit when the battery cannot be used.

The control device 12 may be constituted by a microcomputer or an electronic circuit.

As described above, if the generator coils are actually connected in series or in parallel and the load currents flowing in the series connection and the parallel connection are detected, the same control is performed regardless of the characteristics of the generator. Since the device can be applied, versatility can be provided.

FIG. 6 shows still another embodiment of the present invention. In this embodiment, a voltage detector 13 for detecting the voltage between both ends of the load is provided in addition to the configuration of FIG. The output of the current detector 11 and the output of the voltage detector 13 are input to the control device 12.

In the embodiment shown in FIG. 6, the control device 12
In the same manner as the embodiment of FIG. 5, the magnitude of the current supplied to the load when the power generating coils W1 and W2 are connected in series and the current flowing to the load when the power generating coils W1 and W2 are connected in parallel are determined. Then, when the voltage applied to the load is equal to or less than the set value, the generator coils W1 and W2 are connected by the connection method with the larger load current, and when the voltage applied to the load exceeds the set value, The alternator is operated by connecting the generator coils W1 and W2 in a manner of connection that reduces the applied voltage. With this control, when the battery cannot be used, the voltage at both ends of the pump motor 5 is set to the set value while the power generating coils W1 and W2 are connected in parallel in a region beyond the point C in FIG. Is exceeded (when it becomes excessive), the voltage can be limited by exciting the relay 10 'and connecting the power generation coils W1 and W2 in series. When the battery is ready for use, when the battery is slightly overcharged and the voltage at both ends exceeds a set value, the voltage can be limited by switching the power generation coils W1 and W2 to a series connection.

In the embodiment shown in FIG. 6, the switching of the connection of the power generation coil is controlled by detecting both the load voltage and the load current. However, the control may be performed based only on the load voltage. In this case, when the power generation coils W1 and W2 are connected in series, the voltage supplied to the load and the power generation coil W1
, W2 are connected in parallel to determine the level of the voltage supplied to the load, and the voltage supplied to the load when the power generating coils W1, W2 are connected in series and the power generating coils W1, W2
If the voltage supplied to the load is less than or equal to the set value when both are connected in parallel, the generator coils W1 and W2 are connected by the connection method with the higher voltage supplied to the load and the When the machine is operated and the generating coils W1, W2 are connected in series, the voltage supplied to the load or the generating coils W1, W2,
When one of the voltages supplied to the load exceeds the set value when W2 is connected in parallel, the power supply coils W1 and W2 are connected by the connection method with the lower voltage supplied to the load to generate AC power. Drive the machine.

In each of the above embodiments, a rectifier circuit is provided in common for a plurality of power generating coils, and the connection of the power generating coils is switched on the input side of the rectifier circuit. However, as shown in FIG. A rectifying circuit may be provided for each power generating coil, and the connection of the power generating coil may be switched on the output side of the rectifying circuit. In the embodiment shown in FIG. 7, a power generating coil W1 is connected between input terminals of a rectifying circuit 2 composed of diodes D1 to D4, and a power generating coil W2 is connected between input terminals of a rectifying circuit 2 'composed of diodes D1' to D4 '. Have been. The positive output terminal of the rectifier circuit 2 is connected to one end of a load, and a fixed contact Sa of a changeover switch (or a relay) 10.
And the negative output terminal is connected to fixed contacts Pa and Sb of the changeover switch 10. The positive output terminal of the rectifier circuit 2 'is connected to the movable contact 10a of the changeover switch, and the negative output terminal is connected to the other end of the load and to the movable contact 10b. The method of switching the changeover switch (or relay) is the same as in each of the above embodiments.

In the embodiments shown in FIGS. 6 and 7, when the battery cannot be used, it is preferable to disconnect the load 9 from the circuit.

When the power generating coils W1 and W2 are directly connected in parallel or in series as in the embodiments of FIGS. 1, 5 and 6, the power generating coils W1 and W2 are in phase with each other in synchronization with the rotation of the engine. However, when the connection between the power generating coils W1 and W2 is switched on the output side of the rectifier circuit as shown in FIG. 7, the phases of the outputs of the power generating coils W1 and W2 may be different. .

In the above embodiment, two generator coils W1 and W2 are provided in the generator, but the present invention can be applied to a case where three or more generator coils are provided.

In the above embodiment, the magnet type alternator is used. However, the present invention can be applied to a case where another alternator is used.

In the above embodiment, a manual changeover switch or an electromagnetic relay is used as a switch for switching and connecting the power generation coils in series or in parallel. However, the connection of the power generation coils is switched using a semiconductor switch. You can also.

In order to automatically perform the operation of disconnecting the load 9 from the circuit when the battery cannot be used, the load 9 is connected to the circuit via a switch capable of on / off control. By turning off the switch when the battery becomes unusable, the load 9 can be automatically disconnected from the circuit.

[0038]

As described above, according to the first aspect of the present invention, when a battery cannot be used, a plurality of power generating coils are connected in series to speed up the rise of the voltage and to prevent excessive voltage increase at high speed. When the battery is in a usable state, a plurality of power generation coils are connected in parallel so that a sufficient charging current can be obtained at high speed. There is an advantage that the engine can be operated normally and the battery can be charged without any trouble when the battery can be used. According to the invention described in claim 2, the connection of the power generation coil is switched so that a large load current always flows.
When the battery cannot be used, a large current can be supplied to the pump motor even at a low speed to enable the engine to start, and at a high speed, a current required to obtain a predetermined fuel pressure is supplied to the pump motor. be able to. Therefore, even when the battery cannot be used, the engine can be operated without any trouble. When the battery is in a usable state, a sufficient charging current can be supplied to the battery from a low speed to a high speed. According to the third aspect of the present invention, when the load voltage is equal to or less than the set value, the power generation coil is connected in a connection method in which the load current flows larger, and when the load voltage exceeds the set value, the load voltage is changed. Because the power generation coil is connected in the connection method where the
In addition to the effects obtained by the invention described in claim 2,
Furthermore, an effect is obtained that an excessive voltage can be prevented from being applied to the pump motor and the battery. Further, according to the invention described in claim 4, a sufficient current can be supplied to the pump motor and the battery while preventing the voltage applied to the battery and the pump motor from becoming excessive. According to the fifth aspect of the present invention, since only one rectifier circuit needs to be provided, the circuit configuration can be simplified. According to the invention described in claim 6, the phases of the outputs of the plurality of power generation coils may be different,
The present invention can be implemented regardless of the configuration of the generator.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a circuit used in an embodiment of the present invention.

FIG. 2 is a diagram showing output voltage-current characteristics of a generator used in an embodiment of the present invention.

FIG. 3 is a diagram showing voltage-current characteristics when a pump motor is driven by using a generator having the characteristics shown in FIG. 2;

FIG. 4 is a diagram showing voltage-current characteristics when a battery is charged using a generator having the characteristics shown in FIG. 2;

FIG. 5 is a circuit diagram showing a circuit used in another embodiment of the present invention.

FIG. 6 is a circuit diagram showing a circuit used in still another embodiment of the present invention.

FIG. 7 is a circuit diagram showing a circuit used in still another embodiment of the present invention.

FIG. 8 is a circuit diagram showing a circuit used in a conventional operation method.

[Explanation of symbols]

1 ... AC generator, 2, 2 '... rectifier circuit, 3 ... battery,
5 pump motor, 10 changeover switch, 10 'relay, 10a, 10b movable contact, Sa, Sb, Pa, P
b ... fixed contacts, W1, W2 ... power generation coils.

Claims (6)

(57) [Claims] 1. A method of operating an AC generator for a fuel injection type internal combustion engine which supplies an output voltage to a load including a battery and a pump motor of a fuel injection device for an internal combustion engine through a rectifier circuit. A power generating coil is provided, and when the battery is in a state where it can be used normally,
When the plurality of power generation coils are connected in parallel to operate the AC generator, and the battery is in an up state or a removed state and is not in a state where it can be used normally, the plurality of power generation coils are A method for operating an AC generator for a fuel injection type internal combustion engine, wherein the AC generator is operated by being connected in series. 2. A method of operating an AC generator for a fuel injection type internal combustion engine which supplies an output voltage to a load including a pump motor of a fuel injection device for an internal combustion engine through a rectifier circuit, wherein a plurality of power generation coils are provided in the AC generator. A load current flowing when the plurality of power generation coils are connected in series and a load current flowing when the plurality of power generation coils are connected in parallel are actually detected, and the detected load currents are both provided.
An AC generator for a fuel-injection type internal combustion engine, wherein the AC generator is operated by connecting the plurality of generator coils in a manner of connection in which a larger load current is detected by judging a magnitude of a flow. Driving method. 3. A method of operating an AC generator for a fuel injection type internal combustion engine which supplies an output voltage to a load including a pump motor of a fuel injection device for an internal combustion engine through a rectifier circuit, wherein a plurality of generator coils are provided in the AC generator. provided advance, and detects a voltage applied to the load, in fact a load current that flows when the load current and the plurality of magneto coils flowing when connected to the plurality of magneto coils in series are connected in parallel And the magnitude of the detected both load currents is determined. When the voltage applied to the load is equal to or less than a set value, the detection is performed.
Has been the alternator is operated by connecting the plurality of magneto coils in the manner of the load current is larger connection, when the voltage applied to the load exceeds a set value,
A method for operating an alternator for a fuel injection type internal combustion engine, wherein the alternator is operated by connecting the plurality of generating coils in a manner of lowering the voltage applied to the load. 4. A method of operating an AC generator for a fuel injection type internal combustion engine which supplies an output voltage to a load including a pump motor of a fuel injection device for an internal combustion engine through a rectifier circuit, wherein a plurality of generating coils are provided in the AC generator. It is provided that a voltage supplied to the load when the plurality of power generation coils are connected in series and a voltage supplied to the load when the plurality of power generation coils are connected in parallel are actually detected.
Discriminating the level of both the detected voltages, the voltage supplied to the load when the plurality of power generation coils are connected in series and the voltage supplied to the load when the plurality of power generation coils are connected in parallel When it is detected that both are less than or equal to the set value , the voltage supplied to the load is connected to the plurality of generating coils in a connection manner of a higher one to operate the AC generator, and the plurality of It has been detected that either the voltage supplied to the load when the power generation coils are connected in series or the voltage supplied to the load when the plurality of power generation coils are connected in parallel has exceeded a set value . A method of operating the alternator for a fuel-injection type internal combustion engine, wherein the alternator is operated by connecting the plurality of generating coils in a manner of connection having a lower voltage supplied to the load. . 5. The rectifier circuit according to claim 1, wherein the rectifier circuit is provided in common for the plurality of power generation coils, and switching between the series connection and the parallel connection of the plurality of power generation coils is performed on the input side of the rectifier circuit. 5. A method for operating the AC generator for a fuel injection type internal combustion engine according to any one of 1 to 4. 6. The rectifier circuit is provided for each of the plurality of power generation coils, and each power generation coil is connected between input terminals of the corresponding rectification circuit, and the plurality of power generation coils are connected in series and in parallel. The alternator for a fuel injection type internal combustion engine according to any one of claims 1 to 4, wherein the switching between (i) and (ii) is performed on the output side of a plurality of rectifier circuits respectively corresponding to the plurality of power generating coils. Driving method.