JP4144210B2 - Internal combustion engine drive power generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an internal combustion engine drive power generator including an internal combustion engine and a self-excited field rotation type AC generator driven by the engine.
[0002]
[Prior art]
  In a power generation device driven by an internal combustion engine, in order to save engine fuel, slow-down control is performed to reduce the amount of fuel supplied to the engine when the load is not driven, thereby reducing the engine speed. Sometimes done.
[0003]
  FIG. 2 shows a conventional internal combustion engine-driven power generator configured to perform slow-down control. This power generator includes a self-excited field rotating AC generator 1, a control panel 2, an internal combustion engine (not shown), a power generation coil 3 that induces an AC voltage as the internal combustion engine rotates, and fuel to the internal combustion engine. And a solenoid (electromagnet) 4 for adjusting the supply amount.
[0004]
  The self-excited field rotation type AC generator 1 includes a stator having a capacitor excitation winding Wc and an output winding WL wound with a 90 ° phase difference around a stator core (not shown), and a rotation (not shown). The rotor includes a field winding Wf wound around the core and a rectifier Df connected to both ends of the field winding, and the rotor is driven by the internal combustion engine.
[0005]
  The control panel 2 is provided with a capacitor C1, a breaker 5, an outlet 6, a current transformer 7, a solenoid excitation control circuit 8, and a rectifier 9, and the capacitor C1 is connected to both ends of the capacitor excitation winding Wc.
[0006]
  An AC outlet 6 is connected to both ends of the output winding WL via a breaker 5, and a load (not shown) is connected to the output winding WL via the outlet 6 and the breaker 5.
[0007]
  The generator coil 3 is provided in a magnet generator attached to the internal combustion engine separately from the generator 1, and induces an alternating voltage while the internal combustion engine is operated. The AC voltage induced by the power generation coil 3 is converted into a DC voltage by the rectifier 9 and applied to the power supply terminals 8 a and 8 b of the solenoid excitation control circuit 8. In this example, the power supply coil 3 and the rectifier 9 constitute a solenoid drive power supply unit.
[0008]
  A current transformer 7 constituting a current detector is attached to the wiring connecting the breaker 5 and the outlet 6, and the output of the current transformer 7 is input to the detection signal input terminals 8c and 8d of the solenoid excitation control circuit 8. ing.
[0009]
  The solenoid 4 includes an excitation coil 4a having one end and the other end connected to the positive output terminal 8e and the negative output terminal 8f of the solenoid excitation control circuit 8, respectively, and a movable iron core that is displaced when the excitation coil 4a is excited. 4b and a spring (not shown) for returning the movable iron core 4b to the original position. When the exciting coil 4a is deenergized, the movable iron core 4b is held in the original position, and the exciting coil When 4a is excited, the movable iron core 4b is displaced to the fuel supply amount limiting position.
[0010]
  The movable iron core 4b of the solenoid is connected to a member for adjusting the amount of fuel supplied to the internal combustion engine (a fuel supply amount adjusting member such as a throttle lever) via an appropriate connecting mechanism. The fuel supply amount adjusting member has a first specified amount that is suitable for steady operation (suitable for operating the engine at a steady rotational speed necessary for driving the load). And the solenoid 4 is de-energized so as to be displaceable between the first position and the second position that limits the fuel supply amount to a second specified amount suitable as the amount during standby operation. Sometimes, the fuel supply amount adjusting member is arranged at the first position so that the fuel supply amount becomes the first specified amount, and when the solenoid 4 is excited, the fuel supply amount adjusting member is displaced to the second position. The fuel supply amount is limited to a second prescribed amount that is smaller than the first prescribed amount.
[0011]
  The internal combustion engine is operated at a rated rotational speed (for example, 3,600 [rpm]) required to drive a load when the solenoid is de-energized (when the fuel supply amount is not limited), When excited and the fuel supply amount is limited, the engine is operated at a rotational speed during standby operation lower than the rated rotational speed (eg, 2500 [rpm]).
[0012]
  The solenoid excitation control circuit 8 includes a switch circuit for turning on and off the current supplied from the rectifier 9 to the solenoid 4 according to the detection output of the current transformer 7, and when the current transformer 7 does not detect the load current. When the switch circuit is turned on, a DC voltage is applied from the rectifier 9 to the exciting coil 4a of the solenoid 4 to supply an exciting current to the solenoid, and the current transformer 7 detects the load current. The supply of the excitation current to the solenoid 4 is controlled so that the circuit is turned off and the supply of the excitation current to the excitation coil 4a of the solenoid is stopped (the solenoid is demagnetized).
[0013]
  In the example shown in FIG. 2, the solenoid 4, the current transformer 7 as a current detector, the solenoid drive power supply unit including the power supply coil 3 and the rectifier 9, and the solenoid excitation control circuit 8 pass through the output winding. When the load current is flowing, the amount of fuel supplied to the internal combustion engine is increased to increase the rotational speed of the engine, and when the load current is not flowing, the amount of fuel supplied to the internal combustion engine is decreased to reduce the fuel supply amount. A slow-down control device that reduces the rotational speed of the internal combustion engine is configured.
[0014]
  In the power generator shown in FIG. 2, when an internal combustion engine (not shown) is started, the rotor of the self-excited field rotating AC generator 1 rotates, and the residual magnetism of the rotor core causes the capacitor excitation winding Wc to rotate. Voltage is induced. As a result, a phase advance current flows from the capacitor excitation winding Wc through the capacitor C1. A self-excitation phenomenon occurs due to the magnetizing action due to the phase advance current, and at the same time, the field reverse phase electromotive force generated in the field winding Wf due to the armature reaction of the capacitor excitation winding causes the field winding Wf to pass through the rectifier Df. Magnetic current flows. The rotor core is excited by this field current, and the voltages of the output winding WL and the capacitor excitation winding Wc are established.
[0015]
  In this generator, the field anti-phase electromotive force is increased due to the combined armature reaction between the load current flowing in the output winding WL and the phase advance current Ic, so that a decrease in the induced voltage of the output winding due to the load is suppressed. Voltage fluctuation rate can be kept low.
[0016]
  When a load is connected to the output winding WL, the load current is detected by the current transformer 7, so the solenoid excitation control circuit 8 does not supply the excitation current to the solenoid 4, and the solenoid 8 is in a de-energized state. Retained. Therefore, when the load is connected, the fuel supply amount adjusting member is held at the first position, and the internal combustion engine is supplied with fuel necessary for steady operation.
[0017]
  On the other hand, when the load is disconnected from the output winding WL, no load current is detected by the current transformer 7, so the solenoid excitation control circuit 8 supplies the solenoid 4 with an excitation current. At this time, the solenoid 8 displaces the fuel supply amount adjusting member to the second position on the fuel supply amount reduction side, so that the amount of fuel supplied to the internal combustion engine is limited, the engine speed is reduced, and the standby operation is performed. It becomes a state. This prevents wasteful fuel from being supplied to the internal combustion engine when there is no load, and improves fuel efficiency.Saved.
[0018]
  as mentioned aboveIn a self-excited rotating field AC generator provided with a slow-down device, when driving a load (hereinafter referred to as a soft-start load) in which a so-called soft start is performed that gradually increases the drive current at startup. The load could fail to start.
[0019]
  For example, in an electric tool such as an electric drill that is held by the hand of an operator, if the electric motor suddenly rotates during startup, a large kickback may occur and the hand may go out of order. After being turned on, soft start control is performed in which the drive current is gradually increased by phase control to gradually increase the rotation speed of the motor toward the rated rotation speed.
[0020]
  In the conventional power generator shown in FIG. 2, the voltage induced in the output winding WL is low in the state where the slowdown control is performed and the engine speed is reduced. When the soft start load is connected to the power generator shown in FIG. 2, the load current flowing through the output winding WL at the time of starting becomes very small, and the solenoid excitation control circuit 8 may not be able to deactivate the solenoid 4. The load could fail to start.
[0021]
  In order to prevent such a problem from occurring, the capacitance of the capacitor C1 is increased to increase the excitation capability of the capacitor excitation winding Wc, and a sufficiently high voltage is induced in the output winding WL even during slowdown control. You just have to keep it.
[0022]
  However, when a capacitor having a large capacitance is used as the capacitor C1 so as to increase the induced voltage of the output winding even during slowdown control, the field electromotive force increases due to the armature reaction during steady operation, and the field current If. This increases the temperature of the field winding Wf, which may cause the field winding to burn out.
[0023]
  In view of this, the present applicant, in Japanese Patent Application No. 2000-176743, waits by connecting a slow-down magnetizing capacitor in parallel to the capacitor excitation winding only when no load current flows through the output winding WL. An internal combustion engine drive power generator has been proposed which solves the above problems by allowing a high voltage to be induced in the output winding WL during operation.
[0024]
  FIG. 3 shows a previously proposed power generator. In FIG. 3, the same parts as those shown in FIG. 2 are denoted by the same reference numerals. In the proposed internal combustion engine drive power generator, in addition to the configuration shown in FIG. 2, the control panel 2 further includes a slow-down magnetizing capacitor C2, a capacitor comprising a relay 11, a diode D1, and resistors R1 and R2. An input control circuit 10 is provided.
[0025]
  The relay 11 includes an exciting coil 11y connected to both ends of the exciting coil 4a of the solenoid 4 and a normally open contact 11a that closes when the exciting coil 11y is excited. Are connected in parallel to both ends of a capacitor C1 through a contact 11a and a resistor R1. Anti-R2 is connected in parallel to both ends of the capacitor C2, and a surge absorbing diode D1 is connected in parallel to both ends of the exciting coil 11y.
[0026]
  The resistor R1 is provided to limit the inrush current that flows when the contact 11a is closed, and the resistance value is set to a minimum necessary value to keep the inrush current below an allowable range. The resistor R2 is provided for discharging the charge of the capacitor C2. The other points are the same as those of the power generation device shown in FIG. 2, and the slow-down control device includes a solenoid 4, a solenoid drive power supply unit including the power generation coil 3 and the rectifier 9, and a solenoid excitation control circuit 8. It is configured.
[0027]
  Further, the relay 11 constitutes a capacitor charging control switch that maintains the on state when no load current flows through the output winding WL and maintains the off state when the load current flows.
[0028]
  In the power generation apparatus shown in FIG. 3, when the generator is started with the load disconnected, the relay 11 is excited by the rectified output of the power generation coil 3 immediately after the start and the contact 11a is closed, so that the capacitor C2 is excited by the capacitor. The winding Wc is connected in parallel. Therefore, both capacitors C1 and C2 are connected to the capacitor excitation winding Wc, and the phase advance current flowing through the capacitor excitation winding Wc increases. Therefore, it is possible to increase the magnetizing action by the phase advance current flowing through the capacitor exciting winding Wc, and to quickly establish the voltage of the output winding WL.
[0029]
  In a state where the load is not connected, the solenoid 4 is excited, so that the fuel supply amount adjusting member for the internal combustion engine is displaced to the second position on the fuel supply amount decrease side, and the fuel supply amount is limited. Slow down control is performed. During slowdown control, the engine speed is reduced to the speed during standby operation that is lower than the rated speed. At this time, capacitors C1 and C2 are both connected to the capacitor excitation winding, and the excitation capability is reduced. Therefore, the induced voltage of the output winding WL rises to a voltage higher than the induced voltage during standby operation of this type of conventional power generator.
[0030]
  In this state, when a soft start load is connected to the output winding WL, a necessary starting current can be passed through the load, so that the load can be soft started without any trouble. When the load current exceeds the set value, the solenoid excitation control circuit 8 stops supplying the excitation current to the solenoid 4 and deenergizes the solenoid, so that the fuel supply amount adjusting member is the first fuel supply amount increase side. The fuel supply amount to the engine is increased. As a result, the rotational speed of the engine is increased to the rotational speed at the time of steady operation, and the steady operation of the generator 1 is performed. Further, since the relay 11 is de-energized during the steady operation of the generator, the contact 11a is opened and the capacitor C2 is disconnected from the capacitor exciting winding Wc. Therefore, it is possible to prevent the excitation capability of the capacitor excitation winding from becoming excessive during the steady operation of the generator, and the field current If flowing through the field winding Wf becomes excessive, causing the field winding to burn out. Can be prevented.
[0031]
[Problems to be solved by the invention]
  In the proposed power generator shown in FIG. 3, the load current flowing through the output winding becomes less than the set value, and at the same time the slowdown control device starts the slowdown control operation, the slowdown magnetizing capacitor C2 is turned on. Is done. However, when the slow-down control operation is started, the internal combustion engine is still rotating at the rated speed and a high voltage is induced in the capacitor excitation winding Wc. Therefore, it was necessary to use a high breakdown voltage that can withstand the voltage during rated operation. For this reason, it is necessary to use an expensive and large capacitor C2 for magnetizing at the time of slowdown, and there is a problem that the control unit of the power generator is increased in size and the cost is increased.
[0032]
  An object of the present invention is to perform a soft start without using a high withstand voltage magnetizing capacitor when performing slowdown control in an internal combustion engine drive power generator that drives a self-excited field rotating AC generator by an internal combustion engine. It is to be able to start the load to be performed without hindrance.
[0033]
[Means for Solving the Problems]
  An internal combustion engine drive power generator according to the present invention includes a stator having a capacitor excitation winding connected in parallel with a capacitor and an output winding connected to a load, a field winding wound around a rotor core, A self-excited field rotary AC generator having a rectifier connected to both ends of the field winding and driven by an internal combustion engine; and a load current greater than a set value through the output winding Increase the amount of fuel supplied to the internal combustion engine when it is flowing and rotate the internal combustion engine at the rotational speed necessary to drive the load connected to the output winding. When the load current is not flowing (when the load current flowing through the output winding becomes less than the set value or when the load current becomes zero), the amount of fuel supplied to the internal combustion engine is decreased to Rotational speed is lower than the speed when driving a loadWaitSlow-down control device that maintains the speed, capacitor for slow-down magnetizing connected in parallel to the capacitor excitation winding through a switch for capacitor on / off control that can be turned on / off, and an output winding that exceeds the set value When the load current is flowing, hold the capacitor input control switch in the OFF state, and when the load current exceeding the set value stops flowing through the output winding, wait for a certain delay time to elapse before turning on the capacitor. The internal combustion engineAt the waiting speedAnd a switch control circuit for holding the switch in an ON state during rotation.
[0034]
  The delay time is preferably set to be equal to or longer than the time required for the rotational speed of the internal combustion engine to decrease to the standby speed after the load current of a set value or more stops flowing.
[0035]
  With the above configuration, when a load current exceeding the set value stops flowing through the output winding WL, the capacitor input control switch is turned on after waiting for a certain delay time to elapse. Connect a capacitor for magnetizing during slowdown to the exciting winding in parallel. For this reason, the capacitance of the capacitor connected to the capacitor excitation winding increases, the phase advance current flowing in the capacitor excitation winding increases, and the excitation capability increases. Therefore, a high voltage can be induced in the output winding even during slowdown control, and when a soft-start load is connected to the output winding, a sufficiently large starting current is supplied to reliably start the load. Can be made.
[0036]
  When the load starts and the load current exceeds the set value, the solenoid excitation control circuit deactivates the solenoid. Disconnect from. As a result, the capacitance of the capacitor connected to the capacitor excitation winding decreases during steady operation of the generator (when the load is driven normally). It can be prevented that the electromotive force increases and the field current increases. Therefore, the induced voltage of the output winding at the time of slowdown control can be made sufficiently high and the soft start load can be started without any problem without causing the field winding to burn out during steady operation.
[0037]
  Since the switch for controlling the capacitor input is turned on after the engine speed has dropped to a speed lower than the rated speed, a high induced voltage induced in the capacitor excitation winding during the rated speed is applied to the magnetizing capacitor during slowdown. It can prevent being applied. Therefore, a small and inexpensive capacitor can be used as the magnetizing capacitor.
[0038]
  The slow-down control device includes, for example, a current detector that detects a load current flowing through the output winding, a solenoid that drives a fuel supply amount adjusting member that adjusts the fuel supply amount to the internal combustion engine, and a direct current for driving the solenoid. A solenoid drive power supply that outputs voltage, and when the current detector does not detect a load current greater than the set value, an excitation current is passed from the solenoid drive power supply to the solenoid to excite the solenoid. Is provided with a solenoid excitation control circuit that deenergizes the solenoid when a load current exceeding the set value is detected, and when the solenoid is de-energized, the fuel supply amount adjusting member is displaced to the fuel supply amount increase side. When the internal combustion engine is rotated at a rotational speed necessary for driving the load and the solenoid is excited, the fuel supply amount adjusting member is moved to the fuel supply amount. Configured to displace the quantity side to reduce the rotational speed of the internal combustion engine to a lower speed than the rotational speed at load driving.
[0039]
  When the slow-down control device is configured as described above, the switch control circuit includes a timer circuit that starts a timed operation when the solenoid is excited, and a timer circuit that operates while the solenoid is de-energized and the timer circuit. The capacitor input control switch is kept in the OFF state during the operation, and when the timer circuit finishes the timed operation, the capacitor input control switch is turned ON and the switch is kept ON while the solenoid is excited. And a capacitor driving control switch driving circuit.
[0040]
  The operation time limit of the timer circuit is preferably set to be longer than the time required for the rotation speed of the internal combustion engine to fall to the standby speed after the solenoid is excited.
[0041]
  When the slow-down control device is configured as described above, the capacitor input control switch is a switch that maintains an on state when the solenoid is energized and maintains an off state when the solenoid is de-energized. Is used.
[0042]
  Such a switch is constituted by a relay having an exciting coil excited by a voltage at both ends of a solenoid and a normally open contact that closes when the exciting coil is excited, or a voltage for detecting a voltage at both ends of the solenoid. Turns on when a voltage higher than the set value is detected by the detection circuit and the voltage detection circuit (when the solenoid is energized), and no voltage higher than the set value is detected by the voltage detection circuit Or a switch element that is turned off when the solenoid is de-energized.
[0043]
  The capacitor input control switch is also turned on when a current detector that detects an exciting current flowing through the solenoid and a solenoid that is excited and the current detector detects a current greater than a set value. It can also be constituted by a switch element that is turned off when the current detector no longer detects a current exceeding a set value.
[0044]
  The solenoid drive power supply unit includes a power generation coil provided in a magnet generator attached to the internal combustion engine separately from the self-excited field rotation type AC generator, a rectifier that rectifies an AC voltage generated by the power generation coil, and Can be configured. In addition, the solenoid driving power source can be constituted by a battery.
[0045]
  In the above example, the fuel supply amount is adjusted by operating the fuel supply amount adjusting member with the solenoid. However, the fuel is supplied to the internal combustion engine using an injector (electromagnetic fuel injection valve). When performing, the amount of fuel supplied to the internal combustion engine can be adjusted by controlling the amount of fuel injected from the injector. The amount of fuel injected from the injector can be adjusted by controlling the fuel injection time from the injector.
[0046]
  That is, when an injector is used, a current detector that detects the load current flowing through the output winding, and when the current detector does not detect the load current, the fuel injection time is determined from the injection time during steady operation. Slow down control by the injector drive control unit that controls the injector drive current so that the fuel injection time is returned to the time of steady operation when the current detector detects the load current. A device can be configured.
[0047]
DETAILED DESCRIPTION OF THE INVENTION
  FIG. 1 shows an example of the configuration of an internal combustion engine drive power generator according to the present invention. In FIG. 1, the same parts as those shown in FIG. In the present embodiment, a capacitor switching unit 22 including a slow-down magnetizing capacitor C2, a capacitor charging control switch 20, and a switch control circuit 21 is provided on the generator 1 side.
[0048]
  The capacitor input control switch 20 comprises a phototriac FT having a T2 terminal connected to one end of a capacitor exciting coil Wc, a resistor R10 and a varistor ZR connected in parallel between the T1 and T2 terminals of the triac. The magnetic capacitor C2 is connected between the T1 terminal of the phototriac FT and the other end of the capacitor excitation winding Wc. The varistor ZR is provided to absorb a surge generated when the phototriac FT performs a switching operation, and the resistor R10 discharges the charge of the capacitor C2 through the capacitor excitation winding Wc after the phototriac FT is turned off. It is provided for.
[0049]
  One end of the capacitor C3 is connected to the positive polarity output terminal 8e of the solenoid excitation control circuit 8 through the resistor R11, and the other end of the capacitor C3 is connected to the negative polarity output terminal 8f of the solenoid excitation control circuit 8. The capacitor C3 is charged through the resistor R11 with the DC output voltage of the solenoid excitation control circuit 8. A Zener diode ZD1 having a cathode directed toward one end of the capacitor C3 is connected to both ends of the capacitor C3, and the voltage across the capacitor C3 is made constant by the Zener diode ZD1.
[0050]
  The voltage across the capacitor C3 is applied across the timer capacitor C4 through the resistor R12, and the timer capacitor C4 is charged with a constant time constant through the resistor R12 with a constant voltage across the capacitor C3, thereby causing a timed operation. It is like that.
[0051]
  One end of the capacitor C3 is connected to the anode of the light emitting diode LD through a resistor R13, and the cathode of the light emitting diode is connected to the drain of the FET F1 whose source is connected to the other end of the capacitor C3. The light emitting diode LD is provided so as to constitute a photocoupler together with the phototriac FT, and the phototriac FT is turned on when the light emitting diode LD emits light.
[0052]
  A resistor R14 is connected between the gate and source of the FET F1, and a voltage V1 across the capacitor C4 is applied between the gate and source of the FET F1 through the Zener diode ZD2. A diode D2 having a cathode directed toward one end of the capacitor C3 is connected between a connection point between the capacitor C4 and the resistor R12 and one end of the capacitor C3. A diode D2 is provided for discharging the capacitor C4. The other points are configured in the same manner as the previously proposed internal combustion engine drive power generator shown in FIG. 3, and include a solenoid 4, a solenoid drive power supply unit including a power generation coil 3 and a rectifier 9, and a solenoid excitation control circuit 8. A slow-down control device is configured. A timer circuit which starts a timed operation when the solenoid 4 is excited is constituted by the capacitor C3, the Zener diode ZD1, the capacitor C4, the resistor R12 and the Zener diode ZD2, and the timer circuit is constituted by the FET F1 and the light emitting diode LD. When the operation is finished, a capacitor input control switch drive circuit is configured to turn on the capacitor input control switch and keep the switch on while the solenoid 4 is excited. A switch control circuit 21 is constituted by the timer circuit and the capacitor input control switch drive circuit.
[0053]
  In the power generator shown in FIG. 1, it is sufficient to start the soft start load from the output winding WL during the standby operation (slow down control) of the internal combustion engine with the magnetizing capacitor C2 connected in parallel with the capacitor C1. The capacitance of the magnetizing capacitor C2 is set so that the excitation capability necessary to output a large voltage is obtained. The capacitance of the magnetizing capacitor is set to the minimum necessary value. When set and the capacitor C2 is connected during standby operation, the voltage induced in the capacitor excitation winding is sufficiently lower than the voltage induced during rated operation (higher than the voltage required to start the soft starter load). Keep it like that.
[0054]
  In the internal combustion engine drive power generator shown in FIG. 1, when the load is disconnected in the operating state, the current detector 7 does not detect a load current greater than the set value, so that the solenoid excitation control circuit 8 is connected between the output terminals 8e and 8f. A DC voltage is output, and this DC voltage is applied to the solenoid 4. As a result, the solenoid 4 is excited, so that the fuel supply amount adjusting member that adjusts the fuel supply to the internal combustion engine is displaced to the second position on the fuel supply amount decrease side, thereby limiting the fuel supply amount and slowing down. Control is performed. During the slow-down control, the engine speed is reduced to the standby speed.
[0055]
  The DC voltage output from the solenoid excitation control circuit 8 is applied to the capacitor C3 through the resistor R11 and smoothed, and is made constant by the Zener diode ZD1. The timer capacitor C4 is charged through the resistor R12 by a constant voltage across the capacitor C3, and a timed operation is performed. After this timed operation is started, when a certain time elapses and the voltage V1 across the capacitor C4 exceeds the Zener voltage of the Zener diode ZD2 (when the timed operation is completed), the FET F1 is turned on. The light emitting diode LD emits light, and the phototriac FT is turned on (the capacitor charging control switch is turned on). As a result, the magnetizing capacitor C2 is connected in parallel with the capacitor C1, and the excitation capability of the capacitor exciting winding is enhanced. Therefore, the induced voltage of the output winding WL is higher than that in the state where only the capacitor C1 is connected. Rise up to. In this state, when a soft start load is connected to the output winding WL, a necessary starting current can be passed through the load, so that the load can be soft started without any trouble. When the load current exceeds the set value, the solenoid excitation control circuit 8 stops supplying the excitation current to the solenoid 4 and deenergizes the solenoid, so that the fuel supply amount adjusting member is the first fuel supply amount increase side. The fuel supply amount to the engine is increased. As a result, the rotational speed of the engine is increased to the rotational speed at the time of steady operation, and the steady operation of the generator 1 is performed. Further, since the output voltage of the solenoid excitation control circuit 8 disappears, the charges of the capacitors C3 and C4 are discharged through the resistor R11 and the solenoid 4, so that the FET F1 is turned off and the phototriac FT is turned off. As a result, the magnetizing capacitor C2 is disconnected, so that it is possible to prevent the excitation capacity of the capacitor excitation winding from becoming excessive during the steady operation of the generator, and the field current If flowing through the field winding Wf is excessive. Thus, the field winding can be prevented from being burned out.
[0056]
  In the power generator shown in FIG. 1, it is preferable that the operation time limit of the timer circuit is set to be longer than the time required for the rotation speed of the internal combustion engine to decrease to the standby speed after the solenoid 4 is excited.
[0057]
  In the example shown in FIG. 1, the solenoid is excited by using the power generation coil 3 provided in the magnet generator attached to the internal combustion engine as a power source. However, when a battery is provided, the battery is A solenoid can be excited as a power source.
[0058]
  In the example shown in FIG. 1, the capacitor input control switch is configured by a phototriac, but the capacitor input control switch can also be configured using other semiconductor switches or relays.
[0059]
  In the above description, as a means for adjusting the fuel supply amount of the internal combustion engine, the solenoid 4 is used to excite the solenoid, thereby displacing the fuel supply amount adjusting member to the fuel supply amount decreasing side, By de-energizing, the fuel supply amount adjusting member is displaced toward the fuel supply amount increasing side, but as described in the section for solving the problem, the fuel is supplied to the internal combustion engine by the injector. Alternatively, the amount of fuel supplied to the internal combustion engine can be switched between the amount supplied during steady operation and the amount supplied during standby operation by adjusting the amount of fuel injected from the injector.
[0060]
【The invention's effect】
  As described above, according to the present invention, the OFF state is maintained when the load current exceeding the set value flows through the output winding, and when the load current exceeding the set value stops flowing, the fixed delay time is reached. Since a capacitor input control switch that is turned on after waiting for the current to pass has been provided, and through the switch, a capacitor for magnetizing during slowdown is connected in parallel to the capacitor excitation winding, the capacitor during slowdown control By increasing the capacitance of the capacitor connected to the excitation winding, the excitation capability of the capacitor excitation winding can be increased, and a high voltage can be induced in the output winding. Therefore, when a soft start load is connected to the output winding, a necessary start current can be supplied to ensure that the load is soft started. Also, by turning on the capacitor input control switch after a certain delay time has elapsed since the load current exceeding the set value has ceased to flow, the induced voltage of the output winding decreases and the magnetizing capacitor is Therefore, a capacitor having a low withstand voltage can be used as the magnetizing capacitor, and there is an advantage that the control unit of the power generator can be downsized and the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a configuration example of an internal combustion engine drive power generator according to the present invention.
FIG. 2 is a circuit diagram showing a configuration of a conventional internal combustion engine drive power generator.
FIG. 3 is a circuit diagram showing a configuration of a previously proposed internal combustion engine drive power generator.
[Explanation of symbols]
  DESCRIPTION OF SYMBOLS 1 ... Self-excited field rotation type AC generator, 2 ... Control panel, 3 ... Generator coil, 4 ... Solenoid, 6 ... AC outlet, 7 ... Current transformer (current detector), C1 ... Capacitor, C2 ... Slow down Capacitor for magnetizing during control, 20: Switch for controlling capacitor input, 21: Switch control circuit, 22: Capacitor switching unit, FT: Phototriac, LD: Light emitting diode, C3: Capacitor, ZD1: Zener diode, C4: Timer capacitor , R12 ... resistor, F1 ... FET.

Claims (2)

A stator having a capacitor excitation winding in which capacitors are connected in parallel and an output winding to which a load is connected, a field winding wound around a rotor core, and a rectifier connected to both ends of the field winding A self-excited field rotary AC generator having a rotor driven by an internal combustion engine,
When a load current equal to or higher than a set value flows through the output winding, the amount of fuel supplied to the internal combustion engine is increased to drive the load connected to the output winding at a rotational speed required. The internal combustion engine is rotated, and when the load current exceeding the set value does not flow through the output winding, the amount of fuel supplied to the internal combustion engine is decreased so that the rotational speed of the internal combustion engine is made higher than the speed at the time of load driving. A slow-down control device that maintains a low standby speed,
A slow-down magnetizing capacitor connected in parallel to the capacitor excitation winding through a capacitor input control switch capable of on / off control;
When a load current of a set value or more flows through the output winding, the capacitor input control switch is held in an OFF state, and when a load current of the set value or more stops flowing, a certain delay time elapses. A switch control circuit for waiting for the switch to turn on the capacitor input control switch and holding the switch on while the internal combustion engine is rotating at the standby speed ;
Comprising
The delay time is set to be equal to or longer than a time required for the rotational speed of the internal combustion engine to decrease to the standby speed after the load current of the set value or more stops flowing;
An internal combustion engine drive power generator. A stator having a capacitor exciting winding connected in parallel with a capacitor and an output winding connected to a load, a field winding wound around a rotor core, and a rectifier connected to both ends of the field winding A self-excited field rotating AC generator having a rotor driven by an internal combustion engine,
A current detector that detects a load current flowing through the output winding; a solenoid that drives a fuel supply amount adjusting member that adjusts a fuel supply amount to the internal combustion engine; and a solenoid drive that outputs a DC voltage for driving the solenoid When the load current exceeding the set value is not detected by the power supply unit and the current detector, an excitation current is passed from the solenoid drive power supply unit to the solenoid to excite the solenoid, and the current detector A solenoid excitation control circuit for deactivating the solenoid when the load current is detected, and when the solenoid is deenergized, the fuel supply amount adjusting member is displaced toward the fuel supply amount increasing side to When the internal combustion engine is rotated at a rotational speed necessary for driving the load and the solenoid is excited, the fuel supply amount adjusting member is burned. And slow-down control device to reduce to a low standby speed than is displaced to the feed amount decreasing side rotational speed at load driving rotation speed of the internal combustion engine,
A slow-down magnetizing capacitor connected in parallel to the capacitor excitation winding through a capacitor input control switch capable of on / off control;
A timer circuit that starts a timed operation when the solenoid is excited, and holds the capacitor input control switch in an OFF state while the solenoid is de-energized and while the timer circuit is performing a timed operation, A switch including a capacitor input control switch drive circuit that turns on the capacitor input control switch when the timer circuit finishes the timed operation and maintains the switch on while the solenoid is excited. A control circuit;
Comprising
The operation time limit of the timer circuit is set to be longer than the time required for the rotational speed of the internal combustion engine to decrease to the standby speed after the solenoid is excited,
An internal combustion engine drive power generator.

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