JPH0637871B2 - Engine ignition timing control device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an ignition timing control device for correcting and controlling the ignition timing of an engine so as to improve combustion efficiency while suppressing engine vibration. .

(Prior Art) In recent years, in an automobile engine, by setting the ignition timing of the air-fuel mixture supplied to the combustion chamber of the engine to a more advanced side, it is possible to improve combustion efficiency and improve fuel efficiency. It tends to be done. However, if the ignition timing of the air-fuel mixture is set to the advanced side, the combustion efficiency improves, but the combustion pressure of the air-fuel mixture rises and the torque fluctuation of the engine increases, so engine vibration, that is, so-called engine roughness, becomes large. As a result, there is a drawback that the riding comfort is deteriorated. Therefore, it is necessary to set the ignition timing of the air-fuel mixture to the advance side as much as possible while suppressing the torque fluctuation of the engine to improve the fuel consumption cost.

Therefore, conventionally, for example, in the one disclosed in Japanese Patent Laid-Open No. 56-106065, a combustion pressure detecting means for detecting the rate of change of the combustion pressure of the air-fuel mixture, and an output signal from the combustion pressure detecting means are set to predetermined values. When the rate of change of the combustion pressure is less than a predetermined value based on the output signal (deviation signal) from the comparison means, the ignition advance amount is increased to improve combustion efficiency and improve fuel economy. While trying to improve
When the rate of change in combustion pressure is above a certain value, the ignition advance amount is reduced to lower the combustion pressure and suppress engine vibration to a small level, thus improving combustion efficiency while ensuring good ride comfort. It is designed to effectively improve sex.

(Problems to be Solved by the Invention) By the way, when the engine is cold, it is desired to raise the combustion temperature of the air-fuel mixture to complete the warm-up of the engine at an early stage. If the fuel consumption is improved by increasing the fuel consumption, the combustion temperature of the air-fuel mixture becomes lower with the improvement of the combustion efficiency, so that it takes a long time to warm up the engine, which is not preferable in terms of engine performance.

The present invention has been made in view of the above problems, and an object of the present invention is to provide, in an ignition timing control device for an engine configured to improve fuel efficiency by advancing the ignition timing as described above, a flaness level with respect to the ignition timing. 5 is a quadratic curve that is convex downward, and the same roughness level exists at two points, the ignition timing on the advance side and the ignition timing on the retard side. However, when the engine is warming up, if the roughness level is a small value, if the advance angle is corrected toward the ignition timing on the advance side, it is possible to suppress engine vibration and improve fuel efficiency, while when the engine is cold, the roughness is reduced. When the level is a small value, if the ignition timing is retarded toward the retarded side, the engine vibration can be suppressed to a small value and the heat loss can be increased to accelerate the engine warm-up.
It is intended to suppress the engine vibration to be small both at the time of warming up the engine and at the time of cooling the engine, improve fuel efficiency at the time of warming up the engine, and promote warming up of the engine at the time of cold engine.

(Means for Solving the Problem) In order to achieve the above object, a concrete solving means of the present invention is, as shown in FIG. 1, an ignition timing control device for an engine as described above, that is, a combustion pressure of an air-fuel mixture. A roughness sensor 33 for detecting the roughness state of the engine 1 by, for example,
A comparison / discrimination device 43 for comparing the output of the roughness sensor 33 with a preset reference value, and an output when the output of the roughness sensor 33 is smaller than a preset reference value when the output of the comparison / discrimination device 43 is received. No. 1 ignition timing is controlled to the advance side, and the first roughness control means 48 for controlling the ignition timing of the engine 1 to the retard side when the output of the roughness sensor 33 is larger than the set reference value. In the ignition timing control device, the temperature detecting means 34 for detecting the temperature state of the engine and the output of the temperature detecting means 34 are received, and when the cold state of the engine 1 is detected, the above-mentioned first
Inhibiting means 49 for inhibiting the ignition timing control by the roughness control means 48 and the output of the temperature detecting means 34,
When it is detected that the engine 1 is cold, the ignition timing of the engine 1 is controlled to the retard side when the output of the roughness sensor 33 is smaller than the set reference value, and the output of the roughness sensor 33 is set to the set reference value. And a second roughness control means 50 for controlling the ignition timing of the engine 1 to the advance side when the engine is larger than the above.

(Operation) With the above configuration, in the present invention, the first roughness control means is provided when the roughness level of the engine 1 is smaller than the set reference value in the normal time (that is, when the engine is warmed up after the warming-up operation is completed). Since the ignition timing of the engine 1 is controlled to the advanced side by the engine 48, the engine vibration is suppressed small and the fuel efficiency is improved and the fuel consumption is improved.

On the other hand, when the engine 1 is cold, the ignition timing control by the first roughness control means 48 is prohibited by the prohibition means 49, and instead, the second roughness control means 50 is controlled.
When the roughness level of the engine 1 is smaller than the set reference value when the ignition timing is controlled by, the ignition timing of the engine 1 is controlled to the retard side, which is contrary to the engine warm-up. Is suppressed to a small value, the heat loss is increased, and the warm-up of the engine 1 is promoted.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings starting from FIG.

In FIG. 2, 1 is an engine, 2 is a combustion chamber formed by a piston 4 in which a cylinder 3 of the engine 1 is slidably inserted, and 5 has one end communicating with the atmosphere and the other end opening into the combustion chamber 2. A throttle valve 6 for controlling the amount of intake air, which is an intake passage for supplying intake air through the intake passage 5.
A fuel injection valve 7 for injecting and supplying fuel is arranged downstream of the throttle valve 6, and an intake valve 8 is arranged at the opening to the combustion chamber 2. Reference numeral 9 is an exhaust passage for discharging exhaust gas by opening one end to the combustion chamber 2 and opening the other end to the atmosphere. An exhaust valve 10 is provided at an opening portion of the exhaust passage 9 to the combustion chamber 2. In addition to being disposed, a catalyst device 11 for purifying exhaust gas is provided in the middle of the exhaust passage 9. Reference numeral 15 is a bypass valve that is provided in a bypass passage 16 that bypasses the throttle valve 6 of the intake passage 5 to increase the amount of intake air during idle operation, and 17 is a portion of the exhaust gas in the exhaust passage 9 that is part of the intake passage 5. The recirculation control valve 19 provided in the exhaust gas recirculation passage 18 for recirculating the throttle valve 6 downstream, 19 is the recirculation control valve 1
7 is a solenoid valve for controlling the operation, 20 is a distributor,
Reference numeral 21 is an ignition coil, 22 is a battery, 23 is a key switch, and 24 is a starter.

Further, 30 is an air flow sensor for measuring the amount of intake air,
Reference numeral 31 is a boost sensor that detects the intake negative pressure on the downstream side of the throttle valve 6 in the intake passage 5, 32 is a throttle opening sensor that detects the opening of the throttle valve 6, and 33 is a vibration sensor that detects the vibration of the engine 1. Roughness sensor, 3
4 is a water temperature sensor as a temperature detecting means for detecting the temperature state of the engine 1 by detecting the engine cooling water temperature, 35 is a rotation speed sensor for detecting the engine speed by detecting the crank angle, and 36 is a catalyst sensor for detecting the catalyst temperature. , 37
Detects the air-fuel ratio by the oxygen concentration component in the exhaust gas O
₂ sensors and 38 are position sensors for detecting the opening degree of the recirculation control valve 17, and the detection signals of the sensors 30 to 38 are control units 40 having a CPU.
Has been entered in.

As shown in FIG. 3, the control unit 40 includes therein an integrator 41 that integrates the engine vibration signal from the upper roughness sensor 33 to perform A / D conversion, and an engine vibration signal from the integrator 41. The engine 1 is provided with a differential amplifier 43 as a comparison / determination device that compares the reference value set by the reference value setter 42 with the reference value.
The basic ignition advance amount of is stored in the RAM 44, which is mapped and stored according to the engine operating state determined by the engine speed and the intake air amount, and the signals from the speed sensor 35 and the air flow sensor 30 are received at present. RAM4 for the basic ignition advance amount of the engine corresponding to the engine operating state of
4 and the basic ignition advance amount of the arithmetic unit 45 are corrected based on the output signal from the differential amplifier 43 and the output signals from the water temperature sensor 34 and the O ₂ sensor 37. A control circuit 46 and an output means 47 that waits for the corrected ignition timing corrected by the control circuit 46 and controls the operation of the ignition coil 21 are provided.

Next, the basic operation of the control unit 40 will be described based on the flowchart of FIG. 4 with reference to FIG. First, after initializing in step S1, the engine vibration signal R from the roughness sensor 33 and the engine temperature signal (engine cooling water temperature signal) from the water temperature sensor 34 are read in step S2, and both the engine speed and the intake air amount are read. The signal is read to determine the current engine operating state, and the basic ignition advance amount θ corresponding to the current engine operating state is read from the RAM 44 in step S3.

Then, in step S4, the engine vibration signal R is compared with the reference value r of the reference value setting unit 42, and the deviation x (= R-
After calculating r), in order to correct the basic ignition advance amount θ according to the engine cooling water temperature, in step S5, it is determined whether the current engine cooling water temperature t is equal to or lower than a predetermined value (for example, 40 ° C.) corresponding to the engine cooling time. It is determined whether or not Y at t ≤ 40 ° C
In the case of ES, it is determined that ignition retard control is required, and it is determined in step S6 whether the deviation X is "0" or more, and x
In the case of NO of <0, the ignition timing θ is ahead of the ignition timing θo on the retard side corresponding to the reference value r in FIG. 5, so that the combustion efficiency is good and the heat loss is small. If it is determined that there is a correction ignition timing θ ′ in the following equation θ ′ =
After the ignition timing is delayed by calculation based on θ−x · Δθ (Δθ is a correction factor), the ignition timing is waited in step S8, and the ignition coil 21 is output-controlled in step S9 to cause post-burning. The combustion efficiency is reduced (the heat receiving period and the heat receiving area at the time of combustion of the cylinder 3 are increased to increase the heat loss), and the process returns to step S2.
On the other hand, if YES in step S6, the ignition timing θ is behind θo. Therefore, it is determined that the combustion is unstable, and the correction ignition timing θ ′ is set to the next value in step S10. The amount of retard angle is decreased by calculation based on the equation θ ′ = θ + x · Δθ, and thereafter, the process proceeds to steps S8 and S9, the ignition coil 21 is controlled to lower the combustion temperature, and the process returns to step S2.

If t> 40 ° C. is NO in step S5, it is determined that the engine warm-up is completed, the process proceeds to step S11, and in step S11, it is determined whether or not t ≦ 40 ° C. last time, If YES in t ≦ 40 ° C., it is determined that it is immediately after the completion of engine warm-up, and step S
In step 12, the corrected ignition timing θ'is calculated based on the following equation θ '= θ + θα, and the corrected ignition timing θ'is set to the ignition side ignition timing θ ₁ on the advance side corresponding to the reference value r in FIG.
8, the process proceeds to S9, the output of the ignition coil 21 is controlled, and the process returns to step S2.

On the other hand, if t> 40 ° C. is NO in step S11, it is determined that the engine warm-up has already been completed, and it is determined in step S13 whether the deviation x is “0” or more. When NO for x <0, the corrected ignition timing is on the delay side of θ ₁ , and therefore, it is determined that the engine vibration is small and good, and the routine proceeds to step S10, where the ignition advance amount is increased, If YES in the case of x ≧ 0, it is determined that the corrected ignition timing θ ′ is on the advance side of θ _{1 in} FIG. 5 and the engine vibration is large, and the process proceeds to step S7.
At 7, the ignition advance amount is reduced to reduce engine vibration.

Therefore, when the engine temperature t exceeds the predetermined value (40 ° C.) in step S5, the engine vibration is smaller than the reference value r in step S13, x <0.
While close to the ignition timing theta ₁ of FIG. 5 increases the ignition advance amount in step S10 in the case of the correction ignition timing in step S7, if engine vibration is equal to or larger than the reference value r for x ≧ 0 θ ' Is controlled to retard the ignition timing θ ₁ and returned to the ignition timing θ ₁ , so that the corrected ignition timing θ ′ is advanced to the ignition timing θ ₁ on the advance side corresponding to the reference value r. It constitutes the control means 48.

Further, in step S5, the engine temperature t is set to the predetermined value (4
If the engine warms up above 0 ° C, step S1
By not proceeding to 1 and S13 but proceeding to steps S6 to S10, a prohibiting means 49 for prohibiting the ignition timing control by the first roughness control means 48 is configured. Further, when the engine temperature t is equal to or lower than the predetermined value (40 ° C.) in step S5, the engine vibration is smaller than the reference value r in step S6, x <0.
In this case, in step S7, the corrected ignition timing θ'is controlled to the retard side to approach the ignition timing θo shown in FIG. 5, while if the engine vibration is equal to or greater than the reference value r, x ≧ 0, step S1
At 0, the retard amount of the corrected ignition timing θ ′ is decreased to set the ignition timing θ
The correction ignition timing θ ′ is changed to the reference value r
The second roughness angle control means 50 is configured to retard the ignition timing θo on the retard side corresponding to the above.

Therefore, in the above embodiment, the ignition timing θ is advanced to the ignition timing θ ₁ on the advance side corresponding to the reference value r by the first roughness control means 48 when the engine warms up after the engine warm-up operation is completed. Then, since the ignition timing θ ₁ is controlled so that the ignition timing θ ₁ is maintained thereafter, combustion efficiency is improved and fuel economy is improved while engine vibration is suppressed to be less than the reference value r.

On the other hand, when the engine is cold, the advance control of the ignition timing by the first roughness control means 48 is prohibited by the prohibiting means 49, and the ignition timing θ becomes the second roughness control means 49.
Since the ignition timing θo on the retard side corresponding to the reference value r is controlled by the engine, the engine vibration is suppressed to be less than the reference value r, and the heat loss increases due to the decrease in the combustion efficiency of the air-fuel mixture, resulting in engine warm-up. The opportunity will be accelerated. Therefore, it is possible to improve the warm-up property when the engine is cold, together with the engine vibration reduction control.

In the above embodiment, the reference value r of the roughness level shown in FIG. 5 is set to one value, but when the engine is cold,
Of course, this value may be set for each engine temperature (set to a higher value as the temperature is lower), and the ignition timing may be retarded to the maximum extent within the range that does not cause fire.

Further, in the above-described embodiment, the roughness sensor 33 is configured to directly detect the engine vibration, but it may be configured to detect the torque fluctuation or the rotation fluctuation of the engine.

(Effects of the Invention) As described above, according to the engine ignition timing control device of the present invention, when the engine is warming up, the ignition timing is advanced to the set ignition timing on the advance side, and when the engine is cold,
Since the ignition timing is controlled to the retarded ignition timing, the engine vibration is effectively suppressed both when the engine is warming up and when the engine is cold, while the combustion efficiency is increased to improve fuel efficiency when the engine is warming up. At the same time, when the engine is cold, the heat loss can be increased to improve the engine warm-up property, so that it is possible to ensure both good ride comfort and improved engine performance.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, and FIGS.
FIG. 2 shows an embodiment of the present invention, FIG.
FIG. 4 is a block diagram showing the internal structure of the control unit, FIG. 4 is a flow chart showing the operation of the controller, and FIG. 1 ... Engine, 33 ... Roughness sensor, 34 ... Water temperature sensor (temperature detection means), 43 ... Differential amplifier (comparison / discrimination device), 48 ... First roughness control means, 49 ...
Prohibition means, 50 ... Second roughness control means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Haruo Okimoto No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. In-house (56) Reference JP 58-211546 (JP, A) JP 56-110540 (JP, A)

Claims (1)

[Claims] 1. A roughness sensor for detecting a roughness state of an engine, a comparison / discrimination device for comparing the output of the roughness sensor with a preset reference value, and an output of the roughness sensor for receiving the output of the comparison / discrimination device. First roughness control means for controlling the ignition timing of the engine to the advance side when it is smaller than a preset reference value, and for controlling the ignition timing of the engine to the retard side when the output of the roughness sensor is larger than the preset reference value. An ignition timing control device for an engine, comprising: temperature detection means for detecting a temperature state of the engine; and an ignition timing by the first roughness control means when an engine cold state is detected by receiving an output of the temperature detection means. When the engine cooling time is detected by receiving the output of the temperature detecting means and the prohibiting means for prohibiting the control of, the output of the roughness sensor is A second roughness control means for controlling the ignition timing of the engine to the retard side when the value is smaller than the constant reference value, and to controlling the ignition timing of the engine to the advance side when the output of the roughness sensor is larger than the set reference value. An ignition timing control device for an engine, wherein: