JP2008025361A - Engine control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a smooth ignition-timing control by hardly causing a switching shock, at the time of switching from fuel-cut condition to fuel-recover condition in an engine control system. <P>SOLUTION: In the case when a fuel-cut control is executed by a fuel-cut control means, and fuel-supply is resumed by a fuel-recovering control means from the state where a first-ignition-timing is set, the ignition-timing control means controls so that the ignition-timing becomes a second ignition-timing after the set period has elapsed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an engine control device, and more particularly to an engine control device that reduces a switching shock when the engine is switched from idle to non-idle.

The ignition timing control is performed on the vehicle engine so that the ignition of the spark plug is at an optimal timing according to the driving state.
In this ignition timing control, the basic ignition timing is set by separate table values for the ignition timing at idle and the ignition timing at non-idle, and the ignition timing is switched by the on / off state of the idle switch. .

Conventionally, an engine control device has been designed to alleviate torque shock by gradually reducing the fuel and retarding the ignition timing when decelerating from a relatively high engine speed. When the rotational speed decreases, there is one that prevents the occurrence of engine stall or the like by increasing the fuel quickly and gradually advancing the ignition timing.
Also, the engine ignition timing control device has a delay amount attenuation when the ignition timing is forcibly retarded at the time of fuel recovery from the fuel cut at the time of deceleration, and then the retardation amount is gradually attenuated. Some of them prevent the occurrence of shock by correcting the ignition timing according to other requirements.
Furthermore, the AT vehicle ignition timing control device controls the ignition timing in accordance with the difference in rotational speed between the engine rotational speed and the fuel return rotational speed when a predetermined condition such as when idling is satisfied, and the fuel return rotational speed. Some of them improve fuel efficiency by setting the speed low.
Japanese Patent Laid-Open No. 11-107824 Japanese Patent Laid-Open No. 5-1611 Japanese Patent Laid-Open No. 6-147080

However, conventionally, in an engine control device, in order to prevent a shock due to a sudden change in the ignition timing at the time of switching between the ignition timing at the time of idling of the engine and the ignition timing at the time of non-idle, The ignition timing was changed smoothly.
In addition, in the case of a port injection type engine that injects fuel into the intake port when the fuel cut is restored because the idle switch is turned off from the fuel cut when the idle switch is on, the fuel cut returns to the fuel supply, There was a time lag until the injected fuel was inhaled and ignited to generate torque. Therefore, the ignition timing gradual change process (smoothing process) proceeds from the fuel cut to the fuel supply until the torque is generated, and the effect of the ignition timing gradual change process (smooth process) is achieved. There was an inconvenience that there were few.

  Therefore, an object of the present invention is to ignite at a timing in anticipation of a time lag from when fuel injection is resumed and fuel is sucked into the combustion chamber and torque is generated by combustion when switching from the fuel cut state to the fuel return state. It is an object of the present invention to provide an engine control device that changes the timing and implements smooth ignition timing control with less switching shock.

  The present invention provides a fuel cut control means for cutting off the fuel supply to the engine when the engine is in a deceleration state, and a fuel return control for resuming the fuel supply to the engine after the engine deceleration state is released And a first ignition timing set for the state where the fuel supply is cut by the fuel cut control means and a first ignition timing set for the state where the fuel supply is restarted by the fuel return control means And an ignition timing control means for controlling the ignition timing according to the second ignition timing, wherein the ignition timing control means is configured such that the fuel cut control is performed by the fuel cut control means and the first In the case where the fuel supply is restarted by the fuel return control means from the state where the ignition timing is set, after the set period has elapsed, the ignition timing is And controlling so that the time the second ignition.

  The engine control apparatus according to the present invention has a timing in anticipation of a time lag from when the fuel injection is resumed to when the fuel is returned to the fuel return state and the fuel is sucked into the combustion chamber and the torque is generated by the combustion. By changing the ignition timing, smooth ignition timing control with less switching shock can be performed.

This invention is set for the purpose of performing smooth ignition timing control with little switching shock when fuel supply is resumed from the state where the fuel cut control is performed and the first ignition timing is set. This is realized by controlling the ignition timing to be the second ignition timing after the predetermined period has elapsed.
Hereinafter, embodiments of the present invention will be described in detail and specifically based on the drawings.

1 to 3 show an embodiment of the present invention. In FIG. 3, reference numeral 1 denotes an in-vehicle engine, 2 denotes an intake port, and 3 denotes a combustion chamber. The engine 1 is, for example, a port injection engine that injects fuel into the intake port 2.
The engine 1 includes a fuel injection valve 4 that injects fuel into the intake port 2, an ignition plug 5 that performs ignition in the combustion chamber 3, and an ignition coil 6 that supplies current to the ignition plug 5. .
The engine 1 is provided with a control device 7.
The control device 7 includes engine control means (ECM) 8 that is connected to the fuel injection valve 4 and the ignition coil 6 to control the operating state of the engine 1.
The engine control means 8 includes a crank angle sensor 9 that detects a crank angle as an engine speed, a pressure sensor 10 that detects an intake pipe pressure, a water temperature sensor 11 that detects a cooling water temperature of the engine 1, and a throttle opening. A throttle sensor 12 that detects the vehicle speed, a vehicle speed sensor 13 that detects the vehicle speed, a knock sensor 14 that detects the knocking state of the engine 1, a battery 15 that is a power source that outputs a battery voltage, and an engine 1 that is turned on during idle operation. In addition, it communicates with an idle switch 16 that is turned off during non-idle operation.

  The engine control means 8 includes a fuel cut control means 17 for cutting off the supply of fuel to the engine 1 when the engine 1 is in a deceleration state, and a supply of fuel to the engine 1 after the deceleration state of the engine 1 is released. The fuel return control means 18 for restarting the fuel, the first ignition timing (idle ignition timing) set for the state where the fuel supply is cut by the fuel cut control means 17, and the fuel supply by the fuel return control means 18 There are provided ignition timing control means 19 for controlling the ignition timing based on the second ignition timing (non-idle ignition timing) set for the state where the engine is restarted, and a timer 20 for timing.

The ignition timing control means 19 communicates with the crank angle sensor 9 to set the basic ignition timing by contacting the idle basic ignition timing setting unit 19A for setting the idle basic ignition timing and the crank angle sensor 9 and the pressure sensor 10. Correction value for calculating the correction value of the ignition timing by communicating with the basic ignition timing setting unit 19B, the crank angle sensor 9, the pressure sensor 10, the water temperature sensor 11, the throttle sensor 12, the vehicle speed sensor 13, the knock sensor 14, and the battery 15. The calculation unit 19C, the idle basic ignition timing setting unit 19A, the basic ignition timing setting unit 19B, and the correction value calculation unit 19C are contacted to set the final ignition timing, and the ignition timing signal is transmitted to the ignition coil. And an ignition timing setting unit 19 </ b> D that transmits the data to 6.
Thereby, when the engine 1 is idling, the ignition timing control means 19 controls the ignition timing by adding a correction according to the coolant temperature and the intake pipe pressure to the idle basic ignition timing determined by the engine speed, When the engine 1 is not idle, the ignition timing is controlled by adding various correction values to the basic ignition timing determined by the engine speed and the intake pipe pressure.

The ignition timing control means 19 resumes the fuel supply by the fuel return control means 18 from the state where the fuel cut control is performed by the fuel cut control means 17 and the first ignition timing (idle ignition timing) is set. In this case, after the set period (T) has elapsed, the ignition timing is controlled to become the second ignition timing (non-idle ignition timing). The set period (T) may be the number of ignitions, the number of fuel injections, or time.
The ignition timing control means 19 uses a gradual change process (annealing process) to change the ignition timing from the first ignition timing (idle ignition timing) to the second ignition timing (non-idle ignition timing). The timing is controlled (see FIG. 2).

Next, the operation of this embodiment will be described.
As shown in FIG. 1, when the program of the engine control means 8 is started (step S1), it is determined whether or not the idle switch 16 is on (step S2).
If this step S2 is YES and the engine 1 is idling, the fuel cut control is performed, and the first ignition timing (idle ignition timing) is set (step S3).
If NO in step S2 and the engine 1 is not idling, it is determined whether or not it is within the set period (T) after returning from fuel cut (step S4).
When this step S4 is YES, it is within the set period (T), and the process proceeds to step S3 to hold the first ignition timing (idle ignition timing).
When this step S4 is NO, it is after the set period (T) has elapsed, and a gradual change process (smoothing process) of the ignition timing is performed (step S5). In this case, when the idle switch 16 is turned off, if the set period (T) has already elapsed, that is, if the fuel is not cut when the idle switch 16 is on, immediately, The gradual change process (annealing process) is started.
Then, after the process of step S3 or after the process of step S5, the program is ended (step S6).

Next, the gradual change process (smoothing process) of the ignition timing will be described based on the time chart shown in FIG.
As shown in FIG. 2, when the idle switch 16 is on, the fuel cut state is established. When the idle switch 16 is turned off (time t1), the fuel cut control is canceled and fuel injection is started.
At this time, conventionally, the fuel injected after the fuel cut is sucked into the engine 1 and the ignition timing gradual change process (smoothing process) has progressed before ignition (indicated by a one-dot chain line in FIG. 2).
However, in this embodiment, when a set period (T) has elapsed from the start of fuel injection (time t1) (time t2), a gradual change process (smoothing process) is performed after the torque is generated. Therefore, a gradual change process (smoothing process) is performed after the torque is generated, thereby preventing the occurrence of a switching shock. That is, in this embodiment, when the idle switch 16 is switched from on to off and in a fuel cut state, the ignition timing when the idle switch 16 is on is held for a set period (T). ing.
Note that the inclination angle (θ) of the gradual change process (smoothing process) during the period from when the fuel injection is restarted until the first explosion torque is generated can be changed according to the output of the engine 1. .
That is, in this embodiment, the fuel cut recovery is performed by delaying the transition of the ignition timing when the idle switch 16 is turned from on to off to the non-idle ignition timing by a set period (T) after the fuel cut recovery. Thereafter, by maintaining the first ignition timing (idle ignition timing) until the torque is actually generated, it is possible to reduce the switching shock from when the idle switch 16 is turned on to when it is off.

As a result, the ignition timing control means 19 resumes the fuel supply by the fuel return control means 18 from the state where the fuel cut control is implemented by the fuel cut control means 17 and the first ignition timing (idle ignition timing) is set. In the case where the ignition timing is set, the ignition timing is controlled to become the second ignition timing (non-idle ignition timing) after the set period has elapsed.
As a result, even when the fuel cut state is switched to the fuel return state, the fuel injection is resumed, the fuel is sucked into the combustion chamber 3 of the engine 1, and the ignition is performed at a timing in anticipation of the time lag until the torque is generated by the combustion. Since the timing is changed, smooth ignition timing control with little switching shock can be realized.
The ignition timing control means 19 controls the ignition timing using a gradual change process (annealing process) when changing from the first ignition timing (idle ignition timing) to the second ignition timing.
As a result, since the gradual change process (smoothing process) is performed when the ignition timing is switched, it is possible to realize a smooth ignition timing switching control.

  In this embodiment, when the idle switch is changed from on to off, the fuel cut is performed when the idle switch is changed from on to off even if the ignition timing is not gradually changed (smoothing process). It is also possible to keep only the first ignition timing (idle ignition timing) within the set period (T) after the return.

  When the fuel cut control is performed and the fuel supply is resumed from the state where the first ignition timing is set, the ignition timing becomes the second ignition timing after the set period has elapsed. Control can also be applied to other controls.

It is a flowchart of engine control. It is a time chart of engine control. It is a system configuration figure of an engine control device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Intake port 3 Combustion chamber 4 Fuel injection valve 5 Spark plug 7 Control apparatus 8 Engine control means 9 Crank angle sensor 16 Idle switch 17 Fuel cut control means 18 Fuel return control means 19 Ignition timing control means 20 Timer

Claims (2)

  Fuel cut control means for cutting off fuel supply to the engine when the engine is in a deceleration state, fuel return control means for releasing the engine deceleration state and restarting fuel supply to the engine, and The first ignition timing set for the state where the fuel supply is cut by the fuel cut control means and the second ignition timing set for the state where the fuel supply is resumed by the fuel return control means The ignition timing control means for controlling the ignition timing by the fuel cut control means, wherein the fuel cut control means performs the fuel cut control and the first ignition timing is set. In the case where the fuel supply is restarted by the fuel return control means from the released state, the ignition timing is set to the second timing after the set period has elapsed. Engine control apparatus wherein the controller controls such that the time the fire.   2. The engine according to claim 1, wherein the ignition timing control means controls the ignition timing using a gradual change process when the first ignition timing is changed to the second ignition timing. Control device.

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