JP2002213289A - Deceleration control system for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce shocks by reducing sudden changes in engine torque caused by speed-reduction fuel-cut(F/C) control. SOLUTION: This deceleration control system is provided with an ignition timing control means, a throttle opening detecting means, and an idle switch. The fuel-cut control is effected if throttle opening is smaller than set opening with the idle switch turned on, and when a set period of time has elapsed after ignition timing was retarded. The fuel-cut control is effected if the throttle opening from the detecting means is smaller than the set opening with the idle switch turned on, and when the set period of time has elapsed after the duty of an ISC valve was made smaller than a steady-state value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine deceleration control device, and more particularly to an internal combustion engine capable of reducing a sudden change in engine torque due to deceleration fuel cut (F / C) control and reducing shock. The present invention relates to a deceleration control device.

[0002]

2. Description of the Related Art Some vehicles perform deceleration fuel cut (F / C) control in order to reduce exhaust gas during deceleration, improve fuel efficiency, and protect a catalyst.

The deceleration control device for the internal combustion engine includes:
There is one disclosed in JP-A-2-118265. The vehicle control device disclosed in this publication includes a lock-up clutch that transmits rotation of a turbine shaft to an engine output shaft via a front cover between a turbine and a front cover, and locks the vehicle when a deceleration fuel cut is performed. A control device for a vehicle that engages an up-clutch, comprising: control means for executing fuel cut after a delay time for engaging a lock-up clutch when shifting to deceleration fuel cut and lock-up clutch engagement control; This prevents a sharp drop in the number and ensures a sufficient fuel cut time.

[0004] There is also one disclosed in Japanese Patent Application Laid-Open No. 4-36131. A fluid coupling fastening force control device including engine output control disclosed in this publication includes a fluid coupling interposed between an engine and a drive shaft, and a deceleration coupling force that controls the coupling force of the fluid coupling during deceleration. Control means, fuel cut control means for stopping supply of fuel to the engine at the time of deceleration, and delay control means for delaying control of the fuel cut control means with respect to start of control of the engagement force control means when shifting to a deceleration state And a delay amount setting means for setting the delay amount by the delay control means to a value according to the slip state of the fluid coupling, and performing control of the fastening force of the fluid coupling and fuel cut control during deceleration. The start timing of the fuel cut control has been optimized.

[0005]

By the way, in a conventional deceleration control device for an internal combustion engine, in a normal fuel injection system, the deceleration fuel is controlled by a low throttle opening set in an engine speed table and an idle switch. Cut (F / C) control is performed.

At this time, as shown in FIG. 8, when the low throttle F / C condition is satisfied and the vehicle shifts from the OFF state to the ON state, the fuel cut at deceleration (F / C) control is activated, that is, from the OFF state. ON operation.

However, during deceleration fuel cut (F / C) control, vehicle (AT vehicle) lock-up (also referred to as "L / U") control is performed ("L / UON state").
In this case, the torque changes abruptly, and the torque fluctuation of the internal combustion engine is directly transmitted to the drive system, resulting in a disadvantage that a large shock occurs.

When the vehicle equipped with an auto cruise is traveling on a long downhill, when the vehicle is in an operation state near the fuel cut at deceleration (F / C) control due to the low throttle opening, the set throttle opening is set. In the following cases, the fuel cut at deceleration (F / C) control is activated to generate a shock, and the shock is felt uncomfortable.

[0009] There is also a countermeasure for solving this inconvenience (see Japanese Patent Application Laid-Open No. 2-118265).

That is, as shown in FIG. 8, when the low throttle F / C condition is satisfied and the vehicle shifts from the OFF state to the ON state, the vehicle (AT vehicle) is locked up (also referred to as "L / U"). The control is released, and the deceleration fuel cut (F / C) control is performed after a predetermined delay time (ΔT3) has elapsed since the lock-up control was released.

The lock-up control is an ON operation of the idle switch, and the lock-up control is turned on.

For reference, this fuel cut during deceleration (F /
C) Control will be described with reference to the control flowchart of FIG.

When the internal combustion engine starts and the control program starts (302), it is determined whether the low throttle F / C condition is satisfied and whether the low throttle F / C condition is satisfied (304). If the determination (304) is YES, the vehicle (AT vehicle) is locked up ("L / U").
The control is released (306), and the judgment is made (30).
If NO in 4), a fuel cut during deceleration (F
/ C) Control is shifted to non-operation (312).

Then, the lock-up control release processing (3)
06), it is determined whether or not a predetermined delay time (ΔT3) has elapsed since the lock-up control was released (30).
8) is performed, and if the determination (308) is YES, the operation is shifted to the operation of the fuel cut at deceleration (F / C) control (310), and if the determination (308) is NO, the fuel cut at deceleration is performed. The control is shifted to the non-operation (312) of the (F / C) control.

As a result, by canceling the lock-up control before the deceleration fuel cut (F / C) control is performed, the torque fluctuation of the internal combustion engine is not directly transmitted to the drive system, and the shock is reduced. However, when performing deceleration fuel cut (F / C) control, the idle switch must be changed from the ON state to the OFF state in order to release the lock-up control without fail. There is an inconvenience that fuel efficiency deteriorates due to the rise.

[0016]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, the present invention relates to a deceleration control apparatus for an internal combustion engine that performs fuel cut control when the internal combustion engine is under a low load.
An ignition timing control unit for controlling an ignition timing of the internal combustion engine; a throttle opening detection unit for detecting a throttle opening; an idle switch that is turned on when the internal combustion engine is in an idle operation state; When the throttle opening from the degree detecting means is smaller than the set degree of opening, the idle switch is on, and the set time has elapsed after the ignition timing is retarded by the ignition timing control means, the fuel cut control is performed. Control means for performing the control is provided.

In a deceleration control device for an internal combustion engine that performs fuel cut control when the internal combustion engine is under a low load, a bypass passage for bypassing a throttle valve provided in the intake passage of the internal combustion engine is provided. An ISC valve for adjusting the air amount is provided, and a throttle opening detecting means for detecting a throttle opening is provided.
An idle switch that is turned on when the internal combustion engine is in an idle operation state, wherein the throttle opening from the throttle opening detecting means is smaller than a set opening, the idle switch is on, and the ISC valve is Control means for performing fuel cut control when a set time has elapsed after the duty amount has been made smaller than the steady value is provided.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION
When the throttle opening from the throttle opening detecting means is smaller than the set opening and the idle switch is on, and the set time has elapsed after the ignition timing is retarded by the ignition timing control means, the control is performed. The fuel cut control is performed by the means.

The set time elapses after the throttle opening from the throttle opening detecting means is smaller than the set opening, the idle switch is on, and the duty amount of the ISC valve is made smaller than the steady value. At that time, the fuel cut control is performed by the control means.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 5 show a first embodiment of the present invention. In FIG. 3, reference numeral 2 denotes an internal combustion engine (also referred to as an “engine”) mounted on a vehicle (not shown).

In the intake system of the internal combustion engine 2, an air cleaner 4, a throttle body 6, and an intake manifold (also referred to as "intake manifold") 8 are arranged from the upstream side.
An intake passage 10 communicating with the internal combustion engine 2 is provided.

The air cleaner 4 is provided with an intake air temperature sensor 12 for detecting an intake air temperature, and the throttle body 6 is provided with an air flow meter 14 for detecting an intake air amount.
And a throttle sensor 16, which is a throttle opening detecting means for detecting the opening of a throttle valve (not shown), an auto cruise controller 18, and a throttle opener 20.

In the internal combustion engine 2, the first intake passage 10-1 upstream of the throttle valve and the second intake passage 10-2 downstream of the throttle valve communicate with each other in the intake passage 10, that is, A bypass passage 22 for bypassing the throttle valve is provided, and an ISC valve (ISC) for adjusting the amount of bypass air is provided in the middle of the bypass passage 22.
C: idle speed control, also referred to as “bypass air amount control valve”) 24.

The exhaust system of the internal combustion engine 2 includes an exhaust manifold (also referred to as an “exhaust manifold”) 26.
And a three-way catalyst 28, and an exhaust passage 30 communicating with the internal combustion engine 2.

At this time, a recirculation passage 32 for recirculating a part of the exhaust gas in the exhaust manifold 26 to the intake manifold 8 is provided, and an EGR valve 34 is provided in the middle of the recirculation passage 32.

Further, the internal combustion engine 2 is directed to a combustion chamber (not shown) of a cylinder head (not shown) which is a fuel injection valve (also referred to as an "injector") 3 as a fuel injection means.
6 are provided. The fuel injection valve 36 is connected to a fuel tank (not shown) by a fuel supply passage 38. A fuel pump (also referred to as a “fuel pump”) 40 for supplying fuel to the fuel supply passage 38 is provided in the fuel tank. In the middle of the fuel supply passage 38 in the fuel tank,
A fuel filter and a pressure regulator for adjusting the fuel pressure are provided.

One end of an evaporative passage (not shown) communicates with the fuel tank via a two-way check valve (not shown), and the other end of the evaporative passage communicates with a canister (not shown). One end of the purge passage 42 communicates with the canister. The other end of the purge passage 42 is connected to the intake passage 10 downstream of the throttle valve.
Is in communication with

At this time, a canister purge valve (VSV) 44 is provided in the middle of the purge passage 42.

The internal combustion engine 2 is provided with a water temperature sensor 46 for detecting a cooling water temperature of the internal combustion engine 2, an engine speed sensor 48 for detecting an engine speed, and detecting a crank angle for cylinder discrimination. A crank angle sensor 50 is provided, and an air-fuel ratio detecting means for detecting an air-fuel ratio in the exhaust passage 30, for example, an O2 sensor 52 for detecting an oxygen concentration in exhaust gas is provided.

The fuel injection valve 36, fuel pump 40, water temperature sensor 46, engine speed sensor 48, crank angle sensor 50, intake air temperature sensor 12, and throttle sensor 16
The O2 sensor 52 is connected to a control means (also referred to as an “EPI & AT & A / C controller” or “ECM”) 56 that constitutes the deceleration control device 54.

The deceleration control device 54 will be described with reference to the system flowchart of FIG. 4. In addition to the above, the control means 56 includes a battery voltage, an ignition switch status signal, a starter signal, a vehicle speed, and the like. Signal, electrical load signal, ABS signal, A / C signal, AT signal, P / S pressure switch, lighting switch, brake switch, shift switch, diagnostic switch (in diagnostic monitor coupler), test switch (diagnostic) (In monitor coupler) is connected.

Further, the control means 56 includes a fuel pump relay 58, a main relay 60, a check engine lamp 62, a shift solenoid valve, a lock-up solenoid valve and an indicator light (power mode, O / DO).
FF) 64, A / C compressor relay / A / C condenser fan relay 66, tachometer 68, igniter 7
0, an ignition coil 72 and the like are connected.

As shown in FIG. 2, the control means 56 has an AT control built-in, and includes an AT (also referred to as "E / G") rotational speed, a throttle signal, and an ignition signal. , A vehicle speed signal is input, and the injector 3
6 has a function of performing fuel injection control and ignition timing control, ISC control of the ISC valve 24, and AT control of the automatic transmission, and also functions as ignition timing control means for controlling the ignition timing of the internal combustion engine 2.

The control means 56 is additionally provided with a function of performing fuel cut control when the internal combustion engine 2 is under a low load.

At this time, the deceleration control device 54 is provided with an idle switch (not shown) that is turned on when the internal combustion engine 2 is in an idling operation state, and the throttle opening from the throttle sensor 16 serving as the throttle opening detecting means is provided. Is smaller than the set opening and the idle switch is in the ON state, and when the set time has elapsed after the ignition timing is retarded by the control means 56 functioning as the ignition timing control means, the fuel cut control is performed. Configuration.

More specifically, when the throttle opening from the throttle sensor 16 is smaller than the set opening and the idle switch is on, the internal combustion engine 2 satisfies the low throttle F / C condition. That is, it is determined that the low throttle F / C condition is satisfied.

When the low throttle F / C condition is satisfied, the ignition timing is retarded by the control means 56, and a predetermined delay time (ΔT1), which is a set time from the ignition timing delay, is set. When the time has elapsed, the fuel cut control is performed.

There are two F / C conditions: an F / C line by an idle switch shown by a solid line in FIG. 4 and an F / C line by a low throttle shown by a broken line in FIG.

The lock-up (also referred to as "L / U") control of the vehicle (AT vehicle) is not released until the fuel cut control described above is reached.

Next, the operation will be described with reference to the control flowchart of the control device for deceleration of the internal combustion engine 2 shown in FIG.

When the internal combustion engine 2 starts and the control program starts (102), it is determined whether the low throttle F / C condition is satisfied and whether the low throttle F / C condition is satisfied (104). This judgment (104) is YES
In the case of, the ignition timing is retarded (106), and the judgment is made (10).
If NO in 4), a fuel cut during deceleration (F
/ C) Control is shifted to non-operation (112).

After the ignition timing delay processing (106), a predetermined delay time (ΔT
A judgment (108) is made as to whether or not 1) has elapsed. If the judgment (108) is YES, the fuel cut during deceleration (F
/ C) The control is shifted to the control operation (110), and the judgment (10)
If 8) is NO, the control shifts to deactivation (112) of deceleration fuel cut (F / C) control.

Thus, as in the case of deceleration fuel cut,
Even when the engine torque suddenly changes, as shown in FIG. 5, before the deceleration fuel cut (F / C) control is operated, the engine torque is reduced to a certain degree, and thereafter, the deceleration fuel cut (F / C) is reduced. C) The control can be operated, abrupt changes in engine torque due to fuel cut (F / C) control during deceleration can be alleviated, shocks can be reduced, and drivability can be improved.

Further, an automatic transmission with lock-up ("A
T), it is possible to reduce engine torque fluctuation even when lock-up control and fuel cut control are performed simultaneously, and achieve both improved driving performance and reduced fuel consumption. This is practically advantageous.

FIGS. 6 and 7 show a second embodiment of the present invention.

In the second embodiment, parts having the same functions as those in the first embodiment will be described with the same reference numerals.

In the first embodiment, the ignition timing is retarded by the control means to reduce the engine torque to a certain degree. The second embodiment is characterized by the duty of the ISC valve. ("Dut
y)) is made smaller than the steady value to reduce the engine torque to some extent.

That is, in a deceleration control device for an internal combustion engine that performs fuel cut control when the internal combustion engine is under a low load, a bypass passage that bypasses a throttle valve provided in the intake passage of the internal combustion engine is provided. An ISC valve for adjusting the amount of bypass air is provided, a throttle sensor serving as throttle opening detection means for detecting a throttle opening is provided, and an idle switch is provided which is turned on when the internal combustion engine is in an idle operation state.

When the throttle opening from the throttle sensor is smaller than the set opening and the idle switch is in the ON state, the internal combustion engine satisfies the low throttle F / C condition. F / C
It is determined that the condition is satisfied.

When the low throttle F / C condition is satisfied, the control means causes the duty amount of the ISC valve to be smaller than the steady value, and the duty amount of the ISC valve to be smaller than the steady value. When a predetermined delay time (ΔT2), which is a set time, elapses, the fuel cut control is performed.

Next, the operation will be described with reference to the control flowchart of the internal combustion engine deceleration control device of FIG.

When the internal combustion engine starts and the control program starts (202), it is determined whether the low throttle F / C condition is satisfied and whether the low throttle F / C condition is satisfied (204). If the determination (204) is YES, the duty of the ISC valve (also referred to as "Duty") is made smaller than the steady value (206), and if the determination (204) is NO, The operation is shifted to the non-operation (212) of the fuel cut (F / C) control.

Then, after the process (206) for making the duty amount of the ISC valve smaller than the steady value, it is determined whether or not a predetermined delay time (ΔT2) has elapsed since the time when the duty amount of the ISC valve was reduced (step 206). 208), and if the judgment (208) is YES, the operation is shifted to the operation of the fuel cut at deceleration (F / C) control (210), and if the judgment (208) is NO, the fuel cut at deceleration is performed. (F /
C) Control is shifted to non-operation (212).

Then, even when the engine torque changes abruptly, such as during deceleration fuel cut, as shown in FIG. 7, the engine torque is reduced before the deceleration fuel cut (F / C) control is activated. Can be reduced to a certain extent, and then the fuel cut at deceleration (F / C) control can be operated. The sudden change in engine torque due to the fuel cut at deceleration (F / C) control can be reduced, and the shock can be reduced. It becomes possible and can contribute to improvement of drivability.

Further, an automatic transmission with lock-up (“A
T), it is possible to reduce engine torque fluctuation even when lock-up control and fuel cut control are performed simultaneously, and achieve both improved driving performance and reduced fuel consumption. This is practically advantageous.

The present invention is not limited to the above-described first and second embodiments, but can be variously modified.

For example, in the first and second embodiments of the present invention, an automatic transmission with lock-up (also referred to as "AT") has been described. Instead of the automatic transmission, a manual transmission ("MT") is used. ).

In the first embodiment of the present invention,
In the second embodiment, the ignition timing is retarded by the ignition timing control means and the duty amount of the ISC valve is made smaller than the steady value. However, the ignition timing is retarded and the duty amount of the ISC valve is reduced. It is also possible to adopt a special configuration using control together.

That is, when the low throttle F / C condition is satisfied, ignition timing retard control and ISC valve duty reduction control are sequentially performed. When a set time has elapsed, fuel cut control is performed. Is what you do.

At this time, in addition to the control flow of performing the control of decreasing the duty amount of the ISC valve after the control of retarding the ignition timing, the control of retarding the ignition timing and the control of decreasing the duty amount of the ISC valve are performed. Can be changed.

Then, by sequentially performing the two controls, the engine torque can be reduced in two stages.
The shock caused by the fuel cut control can be reduced.

Further, it is also possible to adopt a special configuration in which when the low throttle F / C condition is satisfied, the fuel supply amount is gradually reduced for a set time.

That is, when the low throttle F / C condition is satisfied, the fuel supply amount is gradually decreased by a set time at a predetermined decreasing rate.
This is for performing fuel cut control.

Then, when the low throttle F / C condition is satisfied, the engine torque can be gradually reduced in advance by gradually reducing the fuel supply amount in accordance with a predetermined reduction rate. This can contribute to shock mitigation by the fuel cut control.

Further, when the low throttle F / C condition is satisfied, it is possible to adopt a special configuration in which a slip state is generated by the clutch control for a set time and the engine torque is gradually reduced.

In this case, when the low throttle F / C condition is satisfied, the slip state is generated by the clutch control, whereby the engine torque can be gradually reduced, and the shock is reduced by the fuel cut control. It can contribute.

[0068]

As described above in detail, according to the present invention, an ignition timing control means for controlling the ignition timing of an internal combustion engine in a deceleration control apparatus for an internal combustion engine which performs fuel cut control at a low load on the internal combustion engine. The throttle opening detecting means for detecting the throttle opening is provided, and the idle switch which is turned on when the internal combustion engine is in the idling operation state is provided, and the throttle opening from the throttle opening detecting means is larger than the set opening. When the set time has elapsed after the ignition switch is turned on and the ignition timing is retarded by the ignition timing control means, control means for performing fuel cut control is provided. Even when the engine torque suddenly changes, the engine torque is reduced to a certain value before the deceleration fuel cut (F / C) control is activated. The fuel cut during deceleration (F / C) control can be operated thereafter, and the sudden change in engine torque due to the fuel cut during deceleration (F / C) control can be reduced, and shock can be reduced. , Which can contribute to the improvement of drivability. Further, in a vehicle equipped with an automatic transmission with lock-up (also referred to as “AT”), even when lock-up control and fuel cut control are performed simultaneously, engine torque fluctuation can be reduced, and drivability can be reduced. It is possible to achieve both improvement and reduction in fuel consumption, which is practically advantageous.

In a deceleration control device for an internal combustion engine which performs fuel cut control when the internal combustion engine is under a low load, a bypass passage is provided for bypassing a throttle valve provided in the intake passage of the internal combustion engine, and a bypass is provided in the bypass passage. An ISC valve for adjusting the air amount is provided, and a throttle opening detecting means for detecting a throttle opening is provided.
An idle switch that is turned on when the internal combustion engine is in an idling operation state is provided. The throttle opening from the throttle opening detecting means is smaller than the set opening, the idle switch is on, and the duty amount of the ISC valve is reduced. Since the control means for performing the fuel cut control is provided when the set time elapses after being made smaller than the steady-state value, the fuel cut at the time of deceleration can be performed even when the engine torque changes suddenly as in the case of the deceleration fuel cut. Before the (F / C) control is operated, the engine torque is reduced to a certain extent, and thereafter the deceleration fuel cut (F / C) control can be operated. This can alleviate sudden changes in engine torque, reduce shock, and contribute to improved drivability. Also,
In a vehicle equipped with an automatic transmission with lock-up (also referred to as “AT”), even when lock-up control and fuel cut control are performed simultaneously, engine torque fluctuation can be reduced, and drivability can be improved. This makes it possible to achieve both reduction in fuel consumption and is practically advantageous.

[Brief description of the drawings]

FIG. 1 is a control flowchart of an internal combustion engine deceleration control device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a system of a control device during deceleration of an internal combustion engine.

FIG. 3 is a system flowchart of a deceleration control device for an internal combustion engine.

FIG. 4 is a diagram showing conditions for fuel cut (F / C) control.

FIG. 5 is a time chart of the deceleration control device for the internal combustion engine.

FIG. 6 is a control flowchart of an internal combustion engine deceleration control apparatus according to a second embodiment of the present invention.

FIG. 7 is a time chart of the deceleration control device for the internal combustion engine.

8A and 8B show a prior art of the present invention, wherein FIG. 8A is a time chart of a first prior art, and FIG. 8B is a time chart of a second prior art.

FIG. 9 is a control flowchart of a deceleration control device for an internal combustion engine according to a second conventional technique.

[Explanation of symbols]

Reference Signs List 2 internal combustion engine 4 air cleaner 6 throttle body 8 intake manifold 10 intake passage 10-1 first intake passage 10-2 upstream second intake passage 12 intake temperature sensor 14 air flow meter 16 throttle sensor 18 auto cruise controller 20 throttle Opener 22 Bypass passage 24 ISC valve 26 Exhaust manifold 28 Three-way catalyst 30 Exhaust passage 32 Reflux passage 34 EGR valve 36 Fuel injection valve 38 Fuel supply passage 40 Fuel pump 42 Purge passage 44 Canister purge valve (VSV) 46 Water temperature sensor 48 Engine speed Sensor 50 Crank angle sensor 52 O2 sensor 54 Deceleration control device 56 Control means 58 Fuel pump relay 60 Main relay 62 Check engine lamp 64 Shift solenoid bar Lube / Lock-up solenoid valve / indicator (power mode, O / D OFF) 66 A / C compressor relay / A / C condenser fan relay 68 Tachometer 70 Igniter 72 Ignition coil

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 41/16 F02D 41/16 P 45/00 310 45/00 310C 314 314C F02P 5/15 F02P 5/15 F

Claims (3)

[Claims] An internal combustion engine deceleration control device for performing fuel cut control when the internal combustion engine is under a low load is provided with an ignition timing control means for controlling an ignition timing of the internal combustion engine, and a throttle opening detection for detecting a throttle opening. Means, an idle switch that is turned on when the internal combustion engine is in an idle operation state is provided, the throttle opening from the throttle opening detection means is smaller than a set opening and the idle switch is on, and A deceleration control device for an internal combustion engine, further comprising control means for performing fuel cut control when a set time has elapsed after the ignition timing has been retarded by the ignition timing control means. 2. A deceleration control device for an internal combustion engine that performs fuel cut control at a low load on the internal combustion engine, wherein a bypass passage is provided to bypass a throttle valve provided in the intake passage of the internal combustion engine, and a bypass is provided in the bypass passage. An ISC valve for adjusting an air amount is provided, a throttle opening detecting means for detecting a throttle opening is provided, and an idle switch which is turned on when the internal combustion engine is in an idle operation state is provided. Control means for performing fuel cut control when the throttle opening is smaller than the set opening and the idle switch is on, and when a set time has elapsed after the duty amount of the ISC valve has been made smaller than a steady value; A deceleration control device for an internal combustion engine, comprising: 3. The control means, wherein the throttle opening from the throttle opening detection means is smaller than the set opening degree, the idle switch is on, and the ignition timing control means delays the ignition timing, ISC
The deceleration control device for an internal combustion engine according to claim 1 or 2, further comprising a function of performing fuel cut control when a set time has elapsed after the valve duty amount is made smaller than a steady value.