JPH0914009A - Engine speed fluctuation preventive device - Google Patents

Abstract

PURPOSE: To provide an engine speed fluctuation preventive device capable of preventing fluctuation of engine speed having its origin in fluctuation of an engine load. CONSTITUTION: An engine speed fluctuation preventive device A has its ΔI detecting unit 15 detecting the decreasing variation quantity of electric generator current I flowing from an electricity generating motor 5 to a battery 4 and, when the decreasing variation quantity is small, functioning of an ISCV correction unit 11, which corrects the intake air quantity, is regarded as being effective. When the decreasing variation quantity is medium, functioning of an ignition timing control unit 17, which corrects the ignition timing, is regarded as being effective, and when the decreasing variation quantity is large, a fuel cut unit 13, which instructs injection stoppage, is regarded as being effective.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine speed fluctuation prevention device for preventing fluctuations in engine speed due to fluctuations in electric load.

[0002]

2. Description of the Related Art For example, when a compressor of an air conditioner is switched from on to off, the discharge current of the battery is greatly reduced, and the battery may be overcharged. Japanese Patent Laid-Open No. 1-19
Japanese Patent No. 0929 discloses a technique (conventional technique 1) of preventing overcharging of a battery by cutting off the field current of the generator to zero the amount of power generation. However, if the amount of power generated by the generator is set to zero, the load applied to the engine sharply decreases, and the engine speed increases.

As a technique for solving this problem, Japanese Patent Laid-Open No. 4-44519 discloses a rotation fluctuation preventing device (prior art 2) having the following configuration. When the transient load change detection means detects an increase / decrease in the transient load of the rotating load of the generator, the ignition timing correction means advances or retards the ignition timing based on the amount of change (configuration 1). When the transient load change detecting means detects an increase / decrease in the transient load of the rotating load of the generator, the fuel injection amount correcting means increases / decreases the fuel injection amount based on the change amount (configuration 2).

[0004]

However, the inventors have found that the prior art 2 also has the following problems. In the case of configuration 1, when the engine load significantly increases / decreases (for example, the compressor for condensing the refrigerant operates / stops in a refrigerating vehicle equipped with a high-power generator), the ignition timing correction means sets the ignition timing. Even if the engine is advanced or retarded, the correction cannot be completed and the engine speed fluctuates. On the contrary, when the engine load is slightly increased / decreased (the electric fan for cooling the engine is operated / stopped), delicate control cannot be performed by the correction for advancing / retarding the ignition timing.

In the correction for increasing / decreasing the fuel injection amount by the fuel injection amount correcting means of the configuration 2, when the engine load is increased / decreased mildly or moderately (operation / stop of the electric fan, turning on / off of the headlight), I cannot control it delicately.

An object of the present invention is to provide an engine rotation speed fluctuation preventing device which can prevent fluctuations in engine speed due to fluctuations in engine load.

[0007]

In order to solve the above-mentioned problems,
The present invention employs the following configuration. (1) A generator that is driven by an engine to generate electric power and appropriately charges an in-vehicle battery that supplies electric power to an electric load;
The intake air control means for determining the amount of intake air supplied to the engine, the ignition timing control means for determining the ignition timing according to the crank position, and the amount of fuel injected into the intake passage are
An engine speed fluctuation preventing device to be mounted on a vehicle, comprising: a fuel injection control unit that is determined according to an intake air amount, wherein a current change amount that detects a change amount of a generator current flowing from the generator to the vehicle-mounted battery. The ignition timing control means determines the detection means, the intake air amount correction means that corrects the intake air amount determined by the intake air amount control means in accordance with the amount of change detected by the current change amount detection means. Ignition timing correction means for correcting the ignition timing based on the amount of change detected by the current change amount detection means, and the intake air amount correction means or the ignition timing correction means is made effective according to the amount of change. And a selection means.

(2) With the configuration of (1) above, the selecting means validates the intake air amount correcting means when the change amount is small, and when the change amount is medium or more, The ignition timing correction means is enabled.

(3) Driven by the engine to generate electricity,
A generator that appropriately charges an on-vehicle battery that supplies electric power to an electric load, intake air control means that determines the amount of intake air supplied to the engine, and fuel injection control that determines the amount of fuel injected into the intake passage. And an intake air amount control means, the engine rotation speed fluctuation preventing device being mounted on a vehicle, the current change amount detecting means detecting a decrease change amount of a generator current flowing from the generator to the vehicle-mounted battery. The intake air amount correction means for correcting the intake air amount determined by the current change amount detecting means in accordance with the decrease change amount detected by the current change amount detecting means, and the time corresponding to the decrease change amount detected by the current change amount detecting means. A fuel cut means for instructing an injection stop and a intake air amount correction means or a selection means for activating the fuel cut means according to the amount of decrease change are provided.

(4) With the configuration of (3) above, the selecting means validates the intake air amount correcting means when the decreasing change amount is small, and when the decreasing change amount is large, the selecting means changes the intake air amount correcting means. Enable the fuel cut means.

(5) Driven by the engine to generate electricity,
A generator that appropriately charges an on-vehicle battery that supplies electric power to an electric load, intake air control means that determines the amount of intake air supplied to the engine, and ignition timing control means that determines ignition timing according to the crank position. An engine rotation speed fluctuation preventing device to be mounted on a vehicle, comprising: a fuel injection control unit that determines the amount of fuel injected into the intake passage according to the intake air amount, and flows from the generator to the vehicle-mounted battery. A current change amount detecting means for detecting a decrease change amount of the generator current, and an ignition timing correction for correcting the ignition timing determined by the ignition timing correcting means in accordance with the decrease change amount detected by the current change amount detecting means. Means, fuel cut means for instructing injection stop for a time corresponding to the decrease change amount detected by the current change amount detection means, and the ignition timing correction hand according to the decrease change amount. Or, provided selection means to enable the fuel cut means.

(6) With the configuration of the above (5), the selecting means enables the ignition timing correcting means when the decreasing change amount is not more than the middle level, and when the decreasing change amount is large, The fuel cut means is enabled.

(7) Driven by the engine to generate electricity,
A generator that appropriately charges an on-vehicle battery that supplies electric power to an electric load, intake air control means that determines the amount of intake air supplied to the engine, and ignition timing control means that determines the ignition timing according to the crank position, An engine speed fluctuation prevention device mounted on a vehicle, comprising: a fuel injection control unit that determines an amount of fuel injected into an intake passage according to an intake air amount, the power generation flowing from the generator to the vehicle-mounted battery. A current change amount detection means for detecting a decrease change amount of the machine current, and an ignition timing correction means for correcting the ignition timing determined by the ignition timing correction means in accordance with the decrease change amount detected by the current change amount detection means. And an intake air amount correction means for correcting the intake air amount determined by the intake air amount control means in accordance with the decrease change amount detected by the current change amount detection means, and the current change And fuel cut means for detecting unit instructs only injection stop time corresponding to the decreased amount of change detected,
The intake air amount correction means, the ignition timing correction means, or the selection means for activating the fuel cut means is provided according to the decrease change amount.

(8) With the configuration of (7) above, the selecting means validates the intake air amount correcting means when the decreasing change amount is small, and when the decreasing change amount is medium, Validates the ignition timing correction means, and validates the fuel cut means when the decrease amount is large.

[0015]

[Action]

[Claim 1] When the electric load is suddenly reduced (increased), the discharge current of the battery is rapidly reduced (rapidly increased). Therefore, the generator suppresses or stops the power generation so that the battery is not overcharged (not overdischarged). As a result, the engine load suddenly decreases (rapidly increases). The current change amount detection means detects the change amount of the generator current flowing from the generator to the vehicle-mounted battery.

The selecting means enables the operation of the intake air amount correcting means or the operation of the ignition timing correcting means in accordance with the amount of change in the generator current detected by the current change amount detecting means. When the operation of the intake air amount correction means is enabled, the intake air amount correction means decreases (increases) the air amount determined by the intake air amount control means in accordance with the magnitude of the current change amount. to correct. As a result, the fuel injection control means decreases (increases) the amount of fuel injected into the intake passage in accordance with the corrected intake air amount, so that a rapid increase (abrupt decrease) in the engine speed is prevented.

When the operation of the ignition timing correction means is enabled, the ignition timing correction means corrects the ignition timing determined by the ignition timing control means such that it is delayed (advanced) in accordance with the magnitude of the current change amount. To prevent a rapid increase (a sharp decrease) in engine speed.

[Claim 2] When the electric load is suddenly reduced (increased), the discharge current of the battery is rapidly reduced (rapidly increased), so that the generator suppresses power generation so that the battery is not overcharged (not over-discharged). Alternatively, the engine load is stopped (increased), so that a phenomenon occurs in which the engine load suddenly decreases (rapidly increases). The current change amount detection means detects the change amount of the generator current flowing from the generator to the vehicle-mounted battery.

When the rate of sudden decrease (sudden increase) of the electric load is small, the amount of change in the generator current is small, and the selecting means enables the operation of the intake air amount correcting means. In this case, the intake air amount correction means sets the air amount determined by the intake air amount control means to
It is corrected so as to decrease (increase) according to the magnitude of the current change amount. As a result, the fuel injection control means decreases (increases) the amount of fuel injected into the intake passage in accordance with the corrected intake air amount, so that the engine speed rapidly increases (rapid decrease).
Is prevented.

When the rate of sudden decrease (sudden increase) of the electric load is relatively large or large, the amount of change in the generator current becomes medium or more, and the selecting means enables the operation of the ignition timing correcting means.
As a result, the ignition timing correction means corrects the ignition timing determined by the ignition timing control means so as to be delayed (advanced) in accordance with the magnitude of the current change amount, and to prevent a rapid increase (rapid decrease) of the engine speed. .

[Claim 3] When the electric load suddenly decreases, the discharge current of the battery sharply decreases, so that the generator suppresses or stops the power generation so that the battery is not overcharged, so that the engine load suddenly decreases. Occurs. The current change amount detecting means detects a decrease change amount of the generator current flowing from the generator to the vehicle-mounted battery. The selection means makes the operation of the intake air amount correction means or the operation of the fuel cut means effective according to the decrease change amount of the generator current detected by the current change amount detection means.

When the operation of the intake air amount correction means is made effective, the intake air amount correction means reduces the air amount determined by the intake air amount control means in accordance with the magnitude of the decrease change amount. to correct. As a result, the fuel injection control means reduces and adjusts the amount of fuel injected into the intake passage in accordance with the corrected intake air amount, so that a rapid increase in engine speed is prevented. When the operation of the fuel cut means is enabled, the fuel cut means instructs the injection stop only for the time period corresponding to the decrease change amount detected by the current change amount detection means, and prevents the engine speed from rapidly increasing.

[Claim 4] When the electric load suddenly decreases, the discharge current of the battery sharply decreases, so that the generator suppresses or stops the power generation so that the battery is not overcharged, so that the engine load suddenly decreases. Occurs. The current change amount detecting means detects a decrease change amount of the generator current flowing from the generator to the vehicle-mounted battery.

When the rate of sudden decrease of the electric load is small, the amount of change in the decrease of the generator current is small, and the selecting means enables the operation of the intake air amount correcting means. In this case, the intake air amount correction means corrects the air amount determined by the intake air amount control means so as to decrease corresponding to the magnitude of the decrease change amount. As a result, the fuel injection control means reduces and adjusts the amount of fuel injected into the intake passage in accordance with the corrected intake air amount, so that a rapid increase in engine speed is prevented.

When the rapid decrease rate of the electric load is large, the decreasing change amount of the generator current is large, and the selecting means enables the operation of the fuel cut means. As a result, the fuel cut means instructs the injection stop only for the time corresponding to the decrease change amount detected by the current change amount detection means, and prevents a rapid increase in the engine speed.

[Claim 5] When the electric load suddenly decreases, the discharge current of the battery sharply decreases, so that the generator suppresses or stops the power generation so that the battery is not overcharged, so that the engine load suddenly decreases. Occurs. The current change amount detecting means detects a decrease change amount of the generator current flowing from the generator to the vehicle-mounted battery.

The selecting means makes the operation of the ignition timing correcting means or the operation of the fuel cut means effective according to the decreasing change amount of the generator current detected by the current change amount detecting means. When the operation of the ignition timing correction means is enabled, the ignition timing correction means corrects the ignition timing determined by the ignition timing control means so as to be delayed corresponding to the magnitude of the decrease change amount,
Prevents a sudden increase in engine speed.

When the operation of the fuel cut means is enabled,
The fuel cut means instructs injection stop only for a time period corresponding to the decrease change amount detected by the current change amount detection means, and prevents a rapid increase in engine speed.

[Claim 6] When the electric load suddenly decreases, the discharge current of the battery sharply decreases, so that the generator suppresses or stops the power generation so that the battery is not overcharged, so that the engine load suddenly decreases. Occurs. The current change amount detecting means detects a decrease change amount of the generator current flowing from the generator to the vehicle-mounted battery.

When the rate of sudden decrease of the electric load is relatively small or small, the decreasing change amount of the generator current is below the middle level,
The selection means enables the operation of the ignition timing correction means. In this case, the ignition timing correction means corrects the ignition timing determined by the ignition timing control means so as to be delayed in accordance with the magnitude of the decrease change amount, and prevents a rapid increase in the engine speed.

When the rate of sudden decrease of the electric load is large, the amount of decrease in the generator current is large, and the selecting means enables the operation of the fuel cut means. As a result, the fuel cut means instructs the injection stop only for the time corresponding to the decrease change amount detected by the current change amount detection means, and prevents a rapid increase in the engine speed.

[Claim 7] When the electric load suddenly decreases, the discharge current of the battery sharply decreases, so that the generator suppresses or stops the power generation so that the battery is not overcharged, so that the engine load suddenly decreases. Occurs.

The current change amount detecting means detects the decrease change amount of the generator current flowing from the generator to the on-vehicle battery. The selecting means validates the operation of the intake air amount correcting means, the ignition timing correcting means, or the fuel cutting means according to the decreasing change amount of the generator current detected by the current change amount detecting means.

When the operation of the intake air amount correction means is enabled, the intake air amount correction means reduces the air amount determined by the intake air amount control means in accordance with the magnitude of the decrease change amount. to correct. As a result, the fuel injection control means reduces and adjusts the amount of fuel injected into the intake passage in accordance with the corrected intake air amount, so that a rapid increase in engine speed is prevented.

When the operation of the ignition timing correction means is made effective, the ignition timing correction means corrects the ignition timing determined by the ignition timing control means so as to be delayed corresponding to the magnitude of the decrease change amount, and Prevents a sudden increase in rotation speed.

When the operation of the fuel cut means is enabled,
The fuel cut means instructs injection stop only for a time period corresponding to the decrease change amount detected by the current change amount detection means, and prevents a rapid increase in engine speed.

[Claim 8] When the electric load suddenly decreases, the discharge current of the battery sharply decreases, so that the generator suppresses or stops the power generation so that the battery is not overcharged, so that the engine load suddenly decreases. Occurs. The current change amount detecting means detects a decrease change amount of the generator current flowing from the generator to the vehicle-mounted battery.

When the rate of sudden decrease of the electric load is small, the amount of change in the decrease of the generator current is small, and the selecting means enables the operation of the intake air amount correcting means. In this case, the intake air amount correction means corrects the air amount determined by the intake air amount control means so as to decrease corresponding to the magnitude of the decrease change amount. As a result, the fuel injection control means reduces and adjusts the amount of fuel injected into the intake passage in accordance with the corrected intake air amount, so that a rapid increase in engine speed is prevented.

When the sudden decrease rate of the electric load is medium, the decrease change amount of the generator current is medium, and the selecting means enables the operation of the ignition timing correcting means. In this case, the ignition timing correction means corrects the ignition timing determined by the ignition timing control means so as to be delayed in accordance with the magnitude of the decrease change amount, and prevents a rapid increase in the engine speed.

When the rate of sudden decrease in electric load is large, the amount of change in decrease in generator current is large, and the selecting means enables the operation of the fuel cut means. In this case, the fuel cut means is
The injection stop is instructed only for a time period corresponding to the decrease change amount detected by the current change amount detection means, and a rapid increase in engine speed is prevented.

[0041]

【The invention's effect】

[Claim 1] The current change amount detection means detects,
According to the amount of change in the generator current flowing from the generator to the on-vehicle battery, the selecting means makes the operation of the intake air amount correcting means or the ignition timing correcting means effective. Therefore, it is possible to prevent the engine speed from fluctuating regardless of the rate of sudden decrease (sudden increase) of the electric load, stabilize idle speed, ensure drivability during traveling, and reduce noise.

[Claim 2] When the amount of change in the generator current is small, that is, when the rate of sudden decrease (sudden increase) in the electric load is small, the selecting means makes the operation of the intake air amount correcting means effective and the accuracy is high. Prevents fluctuations in engine speed and effectively activates ignition timing correction means when the amount of change in generator current is medium or higher, that is, when the rate of decrease (increase) in electrical load is relatively large or large. With this configuration, the change of the engine speed is prevented with good followability.

Therefore, even if the rate of sudden decrease (sudden increase) of the electric load is small, fluctuations in the engine speed can be prevented even at a medium level or higher, and idle speed can be stabilized, drivability can be ensured during running, and noise can be reduced. Can be achieved.

[Claim 3] According to the decreasing change amount of the generator current flowing from the generator to the vehicle-mounted battery detected by the current change amount detecting means, the selecting means operates the intake air amount correcting means, or This is a configuration that enables the operation of the fuel cut means. Therefore, it is possible to prevent fluctuations in the engine speed regardless of the magnitude of the sudden decrease rate of the electric load, stabilize the idle speed, ensure drivability during traveling, and reduce noise.

[Claim 4] When the amount of decrease in the generator current is small, that is, when the rate of sudden decrease of the electric load is small, the selecting means enables the operation of the intake air amount correcting means with high accuracy. Prevents fluctuations in engine speed, and when the amount of change in generator current decrease is large, that is, when the rate of sudden decrease in electrical load is large, activates the fuel cut means to prevent fluctuations in engine speed with good followability. This is the configuration.

Therefore, fluctuations in the engine speed can be prevented regardless of whether the rate of sudden decrease of the electric load is small or large, the idle speed can be stabilized, drivability can be ensured during running, and noise can be reduced.

[Claim 5] The selecting means operates the ignition timing correcting means or the fuel according to the decreasing change amount of the generator current flowing from the generator to the on-vehicle battery detected by the current change amount detecting means. This is a configuration that enables the operation of the cutting means to be effective. Therefore, it is possible to prevent fluctuations in the engine speed regardless of the magnitude of the sudden decrease rate of the electric load, stabilize the idle speed, ensure drivability during traveling, and reduce noise.

[Claim 6] The selecting means activates the ignition timing correcting means when the decreasing change amount of the generator current is at the middle level or less, that is, when the rapid decrease rate of the electric load is relatively small or small. Enable to prevent fluctuations in engine speed, and when the amount of change in generator current decrease is large, that is, when the rate of sudden decrease in electrical load is large, enable the fuel cut means to enable good followability. This is a configuration for preventing the fluctuation of

Therefore, the engine speed can be prevented from fluctuating even if the rate of sudden decrease of the electric load is medium or lower, and the idle speed can be stabilized, the drivability during traveling can be secured, and the noise can be reduced.

[Claim 7] According to the decreasing change amount of the generator current flowing from the generator to the vehicle-mounted battery detected by the current change amount detecting means, the selecting means includes the intake air amount correcting means and the ignition timing correcting means. Is effective, or the operation of the fuel cut means is effective. Therefore, it is possible to prevent fluctuations in the engine speed regardless of the magnitude of the sudden decrease rate of the electric load, stabilize the idle speed, ensure drivability during traveling, and reduce noise.

[Claim 8] When the amount of decrease in the generator current is small, that is, when the rate of decrease in the electrical load is small, the selecting means enables the operation of the intake air correcting means to change the engine speed. Prevent fluctuation with high accuracy.

When the amount of decrease in the generator current is medium, that is, when the rate of decrease in the electric load is medium, the ignition timing correction means is activated and the engine speed fluctuates with good followability. Prevent.

Further, when the amount of decrease in the generator current is large, that is, when the amount of decrease in the electric load is large, the operation of the fuel cut means is enabled to prevent the fluctuation of the engine speed with better followability. Is.

Therefore, it is possible to prevent the engine speed from fluctuating irrespective of the magnitude of the reduction rate of the electric load, to stabilize the idle speed, to secure the drivability during traveling, and to reduce the noise.

[0055]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention (corresponding to claims 1 to 4) will be described with reference to FIGS. As shown in FIG. 1, the engine speed variation prevention device A includes an ISCV correction unit 11, an ignition timing correction unit 12, a fuel cut unit 13, a selection unit 14, and a ΔI detection unit 15 which are incorporated in the ECU 1. Current sensor 21 for detecting generator current I and current detection circuit 2
And a current sensor 31 for detecting the operation of a large-capacity electric load
And an operation detection circuit 3, a battery 4, and
Generator motor 5, ISCV control unit 16, ignition timing control unit 17, fuel injection amount control unit 18, and compressor 6
1, a headlight 62, an electric load such as an electric fan 63, and the engine 7 are assembled to a refrigeration vehicle.

The operation detecting circuit 3 is a target electric load-
A current sensor 3 arranged on a connecting line connecting between the batteries 4
Based on the outputs of 1, 32, and 33, the compressor 61,
It is determined whether at least one of the headlight 62 and the electric fan 63 is turned off → on or turned on → off, and sends an on detection signal and an off detection signal to the ECU 1.

The current detection circuit 2 detects the generator current I flowing from the generator motor 5 to the battery 4 based on the output of the current sensor 21 arranged on the connecting line connecting the battery 4 and the generator motor 5. When the ON detection signal or the OFF detection signal is input, the ΔI detection unit 15 ((generator current I after the ON detection signal is input-generator current I before the ON detection signal is input), (before the OFF detection signal is input) The amount of change ΔId, ΔIu of the generator current I is detected based on the generator current I-the generator current I) after the detection signal is input.

When the off detection signal is input, the selection unit 14
Is small when the change amount ΔIu of the generator current I is small (ΔIu
<I ₁ ) makes the operation of the ISCV correction unit 11 to be described later effective, and the change amount ΔIu is in the middle level (I ₁ ≦ ΔIu <I ₂ ).
Indicates that the operation of the ignition timing correction unit 12 which will be described later is valid, and when the change amount ΔIu is large (ΔIu ≧ I ₂ ), the operation of the fuel cut unit 13 which will be described later is valid.

When the ON detection signal is input, the selection unit 14 determines that the change amount ΔId of the generator current I is small (Δ
Id <I ₁ ) makes the operation of the ISCV correction unit 11 described later effective, and when the change amount ΔId is large ΔId ≧ I ₁ ) makes the operation of the ignition timing correction unit 12 described later effective.

ISCV control unit 1 as intake air control means
An actuator (ISC) 6 adjusts the amount of air passing through an idle adjust passage (not shown) based on various input signals (engine speed signal, cooling water temperature signal, torque converter load signal, vehicle speed signal, etc.). The voltage (adjusted by the voltage applied to the coil) applied to the ISC coil (the amount of air passing through the idle adjustment passage) is determined.
The actuator is attached to a throttle valve control mechanism (not shown) that increases or decreases the amount of intake air supplied to the engine in conjunction with the amount of depression of the accelerator pedal.

When the operation is selected, the ISCV correction unit 11 changes the voltage determined by the ISCV control unit 16 into the voltages Vd and Vu corresponding to the current change amounts ΔId and ΔIu detected by the ΔI detection unit 15, The voltages Vd and Vu are applied to the ISCV coil for a predetermined time.

When the voltage applied to the ISCV coil is increased, the amount of air passing through the idle adjust passage increases, and the amount of fuel injected into the intake passage is controlled according to the corrected intake air amount. The engine output increases because the section 18 adjusts to increase. Further, when the voltage is lowered, the amount of air passing through the idle adjust passage decreases, and the fuel injection amount control unit 18 decreases and adjusts the amount of fuel injected into the intake passage according to the corrected intake air amount. The output drops.

The ignition timing control section 17 has various signals (not shown) (engine speed signal, cooling water temperature signal, vehicle speed signal).
Based on the above, the ignition angle (the cutoff timing of the primary coil current) is determined so that the spark discharge occurs at the optimum crank position. When the operation is selected, the ignition timing correction unit 12 has Δ
The ignition timing control unit 1 determines the retard angle F ₀ and the advance angle F _S according to the current change amounts ΔIu and ΔId detected by the I detection unit 15.
The ignition angle determined by 7 is corrected. The ignition angle is retarded by F _0.
When corrected with, the engine output decreases (engine speed decreases), and when corrected with the advance angle F _S , engine output increases (engine speed increases).

The fuel injection amount control unit 18 energizes the injector so that a predetermined amount of fuel is injected into the intake passage based on the intake air amount and various signals (engine speed signal, cooling water temperature signal) not shown. Determine the period of the pulse to be applied.

When the operation is selected, the fuel cut unit 13 determines the fuel cut time t corresponding to the current change amount ΔIu detected by the ΔI detection unit 15, and is applied to the injector during the fuel cut time t. Break the pulse. still,
As a result, the engine output decreases (the engine speed decreases).

The compressor 61 is an electric compressor for condensing the refrigerant, and operates intermittently (when the temperature of the freezer rises, etc.). Since the power consumption of the compressor 61 is large (about 3 kW), a large discharge current flows from the battery 4 toward the compressor 61 when it is operated, and the current change amount ΔId of the generator current I becomes I ₂ or more. When the operation is stopped, the discharge current stops flowing, so the current change amount ΔI
u is I ₂ or more.

Electric fan 63 for preventing engine overheating
Consumes less power than the compressor 61 (about 2
00W), when activated, a medium discharge current flows from the battery 4. Since the electric power consumption of the electric fan 63 is medium, a medium discharge current flows from the battery 4 toward the compressor 61 when the electric fan 63 operates, and the current change amount ΔId of the generator current I becomes I ₁ or more and less than I ₂ . Further, when the operation is stopped, the discharge current stops flowing, so that the current change amount ΔIu becomes I ₁ or more and less than I ₂ .

The power consumption of the headlight 62 that illuminates the front is relatively small (about 110 W) compared with the electric fan 63 and the compressor 61, and when operating, it is relatively small from the battery 4 toward the headlight 62 and the electric fan 63. The discharge current flows and the current change amount ΔId of the generator current I is I
_{It is} less than ₁ . Further, when the operation is stopped, the discharge current stops flowing, so the current change amount ΔIu becomes less than I ₁ .

The battery 4 supplies electric power to electric loads such as the compressor 61, the headlight 62, the electric fan 63 and the like. The generator motor 5 operates as an electric motor when the engine is started, and is driven by the engine 7 after the engine is started. Then, the lower the terminal voltage of the battery 4 (when the discharge current is large), the more the field current is flowed to generate the large amount of power generation, and the terminal voltage of the battery 4 returns to the normal value (the discharge current is zero or small. In this case, the field current is shut off or reduced to stop or suppress power generation.

Next, the operation of the engine speed fluctuation prevention device A will be described with reference to the flow charts shown in FIGS. During idling or traveling, in step s1, the ISCV control unit 16, the ignition timing control unit 17, and the fuel injection amount control unit 18 perform normal control. In addition, in order to detect the generator current I before the off (on) detection signal is input,
Based on the output of the current sensor 21, the current detection circuit 2 detects the generator current I flowing from the generator motor 5 to the battery 4.

In step s2, the OFF detection signal is the ECU1.
If it has not been input (N
O) proceeds to step s3 and is input (YES)
Proceeds to step s4.

At step s3, the ON detection signal is sent to the ECU1.
If it has not been input (N
O) returns to step s1 and is input (YES)
Proceeds to step s13.

In step s4, the current detection circuit 2 detects the generator current I flowing from the generator motor 5 to the battery 4 based on the output of the current sensor 21. In step s5,
The change amount ΔIu of the generator current I is detected based on (generator current I after input of off detection signal−generator current I before input of off detection signal).

In step s6, the selection unit 14 determines the change amount ΔI.
Determine the size of u. If the change amount ΔIu is small (ΔIu <I ₁ ), the process proceeds to step s7, where the change amount ΔIu
If Iu is medium (I ₁ ≦ ΔIu <I ₂ ), step s
If the amount of change ΔIu is large (ΔIu ≧ I ₂ )
Proceeds to step s11.

In step s7, the selection unit 14 selects the operation of the ISCV correction unit 11, and determines the reduced voltage Vu corresponding to the current change amount ΔIu detected by the ΔI detection unit 15. In step s8, the voltage Vu is applied to the ISCV coil for the set time, and the process returns to step s1.

In step s9, the selection unit 14 selects the operation of the ignition timing correction unit 12, and determines the retard angle Fo corresponding to the current change amount ΔIu detected by the ΔI detection unit 15. In step s10, the ignition angle determined by the ignition timing control unit 17 is corrected to the retard angle F ₀ for a predetermined time, and the process returns to step s1.

In step s11, the selection unit 14 selects the operation of the fuel cut unit 13, and determines the fuel cut time t corresponding to the current change amount ΔIu detected by the ΔI detection unit 15. In step s12, the pulse applied to the injector is cut off during the fuel cut time t, and the process returns to step s1.

In step s13, the current detection circuit 2 detects the generator current I flowing from the generator motor 5 to the battery 4 based on the output of the current sensor 21. Step s14
Then, the change amount ΔId of the generator current I is detected based on (the generator current I before the ON detection signal is input−the generator current I after the ON detection signal is input).

In step s15, the selection unit 14 causes the change amount Δ
The magnitude of Id is determined. If the change amount ΔId is small (ΔId <I ₃ ), the process proceeds to step s16, and if the change amount ΔId is large (ΔId ≧ I ₃ ), the step s1 is performed.
Proceed to 8.

In step s16, the selection unit 14 causes the ISCV
The operation of the correction unit 11 is selected, and the boosted voltage Vd corresponding to the current change amount ΔId detected by the ΔI detection unit 15 is determined. In step s17, the voltage Vd is applied to the ISCV coil for the set time, and the process returns to step s1.

In step s18, the selection unit 14 selects the operation of the ignition timing correction unit 12, and determines the advance angle Fs corresponding to the current change amount ΔId detected by the ΔI detection unit 15. In step s10, the ignition angle determined by the ignition timing control unit 17 is corrected to the advance angle Fs for a predetermined time, and the process returns to step s1.

Next, the advantages of this embodiment will be described. When the rapid decrease rate of the engine load is small (when the headlight 62 is turned on → off), the selection unit 14 enables the operation of the ISCV correction unit 11 to accurately prevent the increase fluctuation of the engine rotation speed, When the rapid decrease rate of the engine is medium (when the electric fan 63 is turned on and off), the operation of the ignition timing correction unit 12 is enabled and the increase fluctuation of the engine speed is prevented with good followability, and the rapid decrease rate of the engine load is increased. Is large (when the compressor 61 is turned on → off), the operation of the fuel cut portion 13 is enabled to prevent the increase fluctuation of the engine rotation speed with better followability.

Further, when the rapid increase rate of the engine load is small (when the headlight 62 is turned from ON to ON), the selecting section 14 enables the operation of the ISCV correcting section 11 to accurately reduce the fluctuation of the engine speed. When the rapid increase rate of the engine load is above the middle level (when the electric fan 63 is turned off → on, or the compressor 61 is turned off → on), the ignition timing correction unit 12 is activated and the engine follows easily. This is a configuration that prevents a decrease fluctuation of the rotation speed.

Therefore, it is possible to effectively prevent the fluctuation of the engine speed regardless of the magnitude of the rapid decrease (rapid increase) of the electric load that causes the engine load to decrease sharply (sudden increase), stabilize the idle speed, and stabilize the driver during traveling. It is possible to secure stability and reduce noise (due to engine speed fluctuation).

The present invention includes the following embodiments in addition to the above embodiments. a. In the above-described embodiment, whether the target electric load is turned on or off is determined based on the outputs of the current sensors 31, 32, 33 arranged on the connection line connecting the electric load and the battery 4. The following configurations may be used. The determination is made based on the magnitude of the generator current I detected by the current detection circuit 2 without using the current sensors 31, 32, 33 and the operation detection circuit 3. When the target electrical load is activated, the electrical load or the like outputs an activation signal, and the presence or absence of the activation signal is used for determination.

B. In the above embodiment, the vehicle is a refrigerated vehicle, but the vehicle may be a home delivery vehicle, a passenger vehicle, an RV vehicle, or a light vehicle. c. The generator motor 5 may be a generator that does not operate as a motor.

[Brief description of the drawings]

FIG. 1 is a block diagram around an engine speed fluctuation prevention device according to the present invention.

FIG. 2 is a flowchart showing an operation of the engine speed fluctuation prevention device.

FIG. 3 is a flowchart showing the operation of the engine speed fluctuation prevention device.

[Explanation of symbols]

 A engine speed fluctuation prevention device 4 battery (vehicle-mounted battery) 5 generator motor (generator) 7 engine 11 ISCV correction unit (intake air amount correction unit) 12 ignition timing correction unit (ignition timing correction unit) 13 fuel cut unit (fuel Cutting unit) 14 Selection unit (Selection unit) 15 ΔI detection unit (Current change amount detection unit) 16 ISCV control unit (Intake air control unit) 17 Ignition timing control unit (Ignition timing control unit) 18 Fuel injection amount control unit (Fuel) Injection control means) 61 Compressor (electric load) 62 Headlight (electric load) 63 Electric fan (electric load)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display F02P 5/15 F02P 5/15 B

Claims (8)

[Claims] 1. A generator that is driven by an engine to generate electric power and appropriately charges an on-vehicle battery that supplies electric power to an electric load; intake air control means that determines the amount of intake air supplied to the engine; and ignition timing. Which is mounted on a vehicle and which has an ignition timing control means for determining the fuel injection amount according to the crank position and a fuel injection control means for determining the amount of fuel injected into the intake passage according to the intake air amount. The current change amount detection means detects the change amount of the current flowing from the generator to the vehicle-mounted battery by detecting the change amount of the generator current, and the intake air amount determined by the intake air amount control means. The intake air amount correcting means for correcting the detected change amount and the ignition timing determined by the ignition timing control means are corrected based on the change amount detected by the current change amount detecting means. Correcting ignition timing correction means, and intake air amount correction means according to the change amount, or
An engine speed fluctuation prevention device, characterized in that it is provided with a selection means for enabling the ignition timing correction means. 2. The selecting means validates the intake air amount correcting means when the change amount is small, and validates the ignition timing correcting means when the change amount is medium or higher. 1. The engine speed fluctuation prevention device according to 1. 3. A generator that is driven by an engine to generate electric power and appropriately charges an in-vehicle battery that supplies electric power to an electric load, intake air control means that determines the amount of intake air supplied to the engine, and an intake passage. And a fuel injection control unit for determining the amount of fuel injected into the vehicle, the engine speed variation preventing apparatus being mounted on a vehicle, the decreasing change amount of a generator current flowing from the generator to the vehicle-mounted battery is detected. Current change amount detection means, intake air amount correction means for correcting the intake air amount determined by the intake air amount control means in accordance with the decrease change amount detected by the current change amount detection means, and the current change amount Fuel cut means for instructing injection stop for a time corresponding to the decrease change amount detected by the detection means; and the intake air amount correction means or the fuel according to the decrease change amount. An engine speed fluctuation prevention device, characterized in that it is provided with selection means for activating the cutting means. 4. The selection means validates the intake air amount correction means when the reduction change amount is small, and validates the fuel cut means when the reduction change amount is large. Engine rotation speed fluctuation prevention device. 5. A generator that is driven by an engine to generate electric power and appropriately charges an on-vehicle battery that supplies electric power to an electric load, intake air control means that determines the amount of intake air supplied to the engine, and ignition timing. Which is mounted on a vehicle and which has an ignition timing control means for determining the fuel injection amount according to the crank position and a fuel injection control means for determining the amount of fuel injected into the intake passage according to the intake air amount. The current change amount detecting means detects the current change amount detecting means for detecting a decrease change amount of the generator current flowing from the generator to the vehicle-mounted battery, and the ignition timing determined by the ignition timing correcting means. Ignition timing correction means for correcting in response to the reduced change amount, and a fuel cut instruction for instructing injection stop for a time corresponding to the reduced change amount detected by the current change amount detection means. An engine speed fluctuation prevention device comprising: a stage; and a selection unit that makes the ignition timing correction unit or the fuel cut unit effective according to the decrease change amount. 6. The selection means validates the ignition timing correction means when the reduction change amount is at a medium level or less, and validates the fuel cut means when the reduction change amount is large. The engine speed fluctuation prevention device described. 7. A generator that is driven by an engine to generate electric power and appropriately charges an on-vehicle battery that supplies electric power to an electric load, intake air control means that determines the amount of intake air supplied to the engine, and ignition timing. An engine rotation speed fluctuation preventing device to be mounted on a vehicle having ignition timing control means determined according to a crank position and fuel injection control means determined for an amount of fuel injected into an intake passage according to an intake air amount. There, the current change amount detection means for detecting the decrease change amount of the generator current flowing from the generator to the in-vehicle battery, and the ignition timing determined by the ignition timing correction means, the current change amount detection means detected. Ignition timing correction means for correcting in accordance with the decrease change amount, and the intake air amount determined by the intake air amount control means with respect to the decrease change amount detected by the current change amount detection means. An intake air amount correction means for correcting the intake air amount, a fuel cut means for instructing the injection stop for a time corresponding to the decrease change amount detected by the current change amount detection means, and the intake air amount according to the decrease change amount. An engine speed variation prevention device, comprising: an amount correction means, an ignition timing correction means, or a selection means for activating the fuel cut means. 8. The selecting means validates the intake air amount correcting means when the decreasing change amount is small, and validates the ignition timing correcting means when the decreasing change amount is medium, The engine speed fluctuation prevention device according to claim 7, wherein the fuel cut means is enabled when the amount of decrease change is large.