JP3147628B2 - Engine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an engine mounted on a ship or an automobile, and more particularly, to a control device for an engine when the operating condition of the engine reaches a predetermined judgment level. The present invention relates to an engine control device that notifies a driver or a passenger of a ship or a car.

[0002]

2. Description of the Related Art In an engine mounted on a ship, an automobile, or the like, the operating conditions of the engine are determined at a predetermined determination level for the purpose of keeping the operating conditions of the engine good and further protecting the engine. That is, for example, when the oil pressure level of the marine engine or the cooling water temperature of the water-cooled engine deviates from a predetermined determination level (normal range) and reaches an abnormal range, this may cause overheating and seizure of the engine. Therefore, in general, when the water temperature or the oil pressure level reaches a determination level (abnormal range), the abnormality is detected by a sensor or a switch, and a warning light or a warning buzzer is used to notify the driver or the passenger. It was configured to notify.

[0003]

However, in the above-mentioned conventional control device, the warning light or the warning buzzer may not be noticed due to the carelessness of the driver, so that the treatment for the abnormality may be delayed and the engine may be damaged. Particularly, in the case of a ship, the warning by the warning light or the warning buzzer often cannot be identified depending on the size of the hull or the state of the sea (including on a lake or a river). Further, it is conceivable to make the notification thorough by enlarging or adding a warning light or a warning buzzer. However, in this case, not only the configuration becomes complicated but also the cost increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object the purpose of a simplified configuration.
An object of the present invention is to provide an engine control device capable of reliably reporting that an operating condition of an engine has reached a predetermined determination level.

[0005]

In order to achieve the above object, an engine control device according to the present invention, when an operating condition of an engine reaches a predetermined judgment level set in advance, is notified. A signal generating means for generating a signal indicating the signal, and in response to the input of the determination signal by the signal generating means, the combustion of the cylinder is forcibly stopped for a predetermined period in order to change the engine sound generated by the engine, thereby suppressing a steep rotation speed fluctuation. It is the gist of the invention that it has a combustion stopping means for causing it.

According to a second aspect of the present invention, in the engine control device according to the first aspect, the combustion stopping means stops the combustion when the rotation speed fluctuation during execution of the combustion stop exceeds a predetermined allowable range. Is configured to be stopped.

According to a third aspect of the present invention, in the engine control device according to the first or second aspect, the combustion stopping means reduces the number of ignition stop cylinders or the predetermined number of fuel injection stop cylinders arranged in combustion order. Thus, the combustion stop period is defined.

According to a fourth aspect of the present invention, in the engine control device according to the first to third aspects, the combustion stopping means repeats the stopping of the combustion at a predetermined cycle longer than a period for executing the stopping of the combustion. It is configured to run.

According to a fifth aspect of the present invention, in the engine control device according to the fourth aspect, the signal generating means generates a plurality of signals for each operation condition to be determined, and the combustion stopping means generates the plurality of signals. The combustion stop cycle is switched for each signal in accordance with the signal of the generating means.

[0010]

According to the first aspect of the present invention, when the operating condition of the engine reaches a predetermined judgment level, the signal generating means generates a signal indicating that. The combustion stopping means forcibly stops combustion of the cylinder for a predetermined period in order to change the engine sound generated by the engine in response to the input of the determination signal from the signal generating means, thereby causing a steep rotation speed fluctuation. Then, the change in the engine sound is determined by the driver or the occupant of the ship or the car, so that the engine operating condition has reliably reached the predetermined determination level.

According to the second aspect, the combustion stopping means stops the combustion stop when the rotation speed fluctuation during the execution of the combustion stop exceeds a predetermined allowable range. That is, according to the second aspect, a steep rotation fluctuation is obtained, and the rotation fluctuation during the combustion stop period is kept within a predetermined allowable range. Inadvertent speed changes and the like are avoided during the operation.

According to the third aspect, the combustion stopping means defines the combustion stopping period by a predetermined number of ignition stop cylinders or a predetermined number of fuel injection stop cylinders arranged in combustion order. In this case, since the combustion stoppage is defined by the number of combustion stop cylinders, a substantially constant change in engine sound is always obtained regardless of the change in the rotational speed.

According to the fourth aspect, the combustion stopping means repeatedly executes the combustion stop at a predetermined period longer than the period during which the combustion stop is executed. In this case, the instantaneous rotation fluctuation caused by the combustion stopping means can be returned to the original rotation number by the time the next rotation fluctuation occurs, and there is no fluctuation in the overall rotation number. Further, the driver can more reliably identify the repeatedly generated engine sound.

According to the fifth aspect, the signal generating means generates a plurality of signals for each operation condition to be determined. The combustion stopping means switches the combustion stopping cycle for each signal in accordance with the signal from the signal generating means. That is, the driver can identify the cause of the change in the engine sound by distinguishing the change in the engine sound due to the difference in the combustion stop cycle.

[0015]

【Example】

(First Embodiment) A first embodiment in which the present invention is embodied in an ignition timing control device for a marine engine will be described below with reference to the drawings.

FIG. 1 is a block diagram schematically showing an ignition timing control device according to this embodiment. As shown in FIG. 1, in a six-cylinder water-cooled engine (hereinafter simply referred to as an engine) 1, a piston 3 is disposed in a cylinder block 2. A combustion chamber 5 defined by a cylinder block 2 and a cylinder head 4 is formed above the piston 3, and an ignition plug 6 is disposed in the combustion chamber 5. Combustion chamber 5
Is connected to an intake pipe 9 and an exhaust pipe 10 via an intake valve 7 and an exhaust valve 8.

The cylinder block 2 has a water temperature switch 11 for outputting an on / off binary signal in accordance with the temperature of the cooling water circulating in the engine 1, and an on / off binary value in accordance with the engine oil pressure. Hydraulic switch 1 that outputs a signal
2 are arranged. Further, the exhaust pipe 10 is provided with an exhaust temperature switch 13 that outputs a binary on / off signal in accordance with the temperature of the exhaust gas. Each of the above switches 11 to
Reference numeral 13 outputs an ON signal at the time of occurrence of an abnormality (at the time of increasing water temperature, at the time of decreasing oil pressure, or at the time of increasing exhaust temperature), using a predetermined judgment level, which may hinder the operation of the engine 1. Further, the intake pipe 9 is provided with a fuel injection valve 14 for injecting and supplying pressurized fuel from a fuel supply system (not shown) to the intake pipe 9 for each cylinder.

The distributor 1 is connected to the ignition coil 17.
The high voltage for ignition generated in the ignition coil 17 is distributed to the ignition plug 6 of each cylinder by the distributor 15. The distributor 15 has a rotation axis of 30 ° C.
A rotation angle sensor 16 that generates a rotation angle pulse signal for each A is provided.

An electronic control unit (hereinafter referred to as an ECU) 20
Is a CP that executes various calculations based on a control program.
U (central processing unit) 21 and ROM (read only memory) 22 for storing control programs and initial data in advance
And a RAM (random access memory) 23 for temporarily storing various input signals and data necessary for calculation, and an I / O (input / output) circuit 24 for inputting and outputting data to and from external devices. I have. The ECU 20 includes a water temperature switch 1
1, a hydraulic switch 12, an exhaust temperature switch 13, a rotation angle sensor 16, and the like are connected.

Then, the CPU 21 calculates a fuel injection amount according to the operating condition of the engine 1 at that time, and drives the fuel injection valve 14 so as to have the same fuel injection amount. Also, CP
U <b> 21 calculates the ignition timing (timing of energization by the ignition coil 17 and energization cutoff timing) for each ignition cylinder according to the operating conditions of the engine 1 at that time, and ignites the ignition plug 6 based on the ignition timing. Further, the CPU 21
When an abnormality occurs, ignition stop (combustion stop) is forcibly executed based on a control program described later.

In this embodiment, the water temperature switch 11,
The hydraulic pressure switch 12 and the exhaust gas temperature switch 13 constitute a signal generating means, and the CPU 21 constitutes a combustion stopping means.

Hereinafter, the operation of the ignition timing control device configured as described above will be described with an example in which a water temperature abnormality occurs. The flowchart of FIG. 2 is a processing routine for controlling the ignition stop when an abnormality occurs. This routine is executed by the CPU 21 at the ignition crank angle interval for each cylinder (120 ° A interval in the present embodiment). That is, the routine of FIG. 2 is processed in synchronization with the ignition, and the ignition stop is controlled for each cylinder by the routine. The flowchart of FIG. 3 is a processing routine executed by the CPU 21 every 5 msec to determine the occurrence of a water temperature abnormality.

FIG. 4 is a timing chart showing the operation of the ignition stop control when an abnormality occurs. In FIG. 4, (a) is when an abnormality occurs in the engine 1 (when the water temperature rises).
Indicates an abnormality occurrence flag, and the abnormality occurrence flag = “1” indicates that an abnormality has occurred, and the abnormality occurrence flag =
“0” indicates no abnormality. (B) shows an ignition stop flag. The CPU stops the ignition stop flag = “1” while
21 is performed to stop the ignition. (C) shows an ignition stop frequency counter for measuring the number of ignition stop times, and the value of this counter corresponds to the number of ignition stop cylinders. (D) shows an ignition stop cycle timer that measures the time of one cycle in which the ignition stop control is performed. (E) shows the engine speed, and (f) shows a sound pressure waveform accompanying a change in engine sound. Note that the sound pressure waveform of (f) indicates an envelope of a waveform extracted by a band-pass filter of a predetermined frequency (for example, 500 Hz).

The operation of this control will be briefly described with reference to FIG. When a water temperature abnormality occurs at the timing of t1, both the abnormality occurrence flag and the ignition stop flag are set to "1". At this time, the ignition is stopped in accordance with the setting of the ignition stop flag, and a sharp decrease in the engine speed occurs. The ignition stop counter and the ignition cycle measurement timer are once reset to predetermined values, and thereafter are incremented with time.

At the timing of t2, the ignition stop number counter reaches the preset ignition stop number S1, and the ignition stop flag is reset to "0". By resetting this flag, the ignition operation by the ignition plug 6 is restarted. The engine speed increases with the restart of ignition,
It returns to the rotation speed before the ignition was stopped. When the rotation speed fluctuates, the sound pressure waveform changes as shown in FIG. 4F due to a steep rotation speed edge (a drop of about 100 rpm), and an appropriate engine sound (sound generated by vibration, exhaust sound, etc.) is generated. . The ignition stop frequency S1 is set to an optimum value based on experimental data or the like, and is set according to a desired rotation fluctuation, speed change, engine sound, or the like. In the present embodiment (in the case of a six-cylinder engine), in order to cause a decrease in the engine speed of about 100 rpm, the number of times (S1
= 6).

Thereafter, at a timing t3, the ignition stop cycle timer reaches a predetermined time (ignition stop time T), the ignition stop flag is set to "1" again, and the ignition is stopped.

As described above, since the ignition is forcibly stopped only during the period when the ignition stop flag is "1", a sharp drop in the engine speed occurs, and the engine 1 has a noise caused by vibrations and exhaust gas. Occurs. This engine sound is generated at a predetermined ignition stop period T.

Hereinafter, the ignition stop control processing routine of FIG. 2 will be described in detail with reference to the timing chart of FIG. When the routine of FIG. 2 is started, the CPU 21 first determines in step 101 whether or not a water temperature abnormality has occurred based on whether or not the abnormality occurrence flag is set to “1”. Here, the abnormality occurrence flag is set by the processing routine for determining a water temperature abnormality in FIG.

More specifically, in FIG. 3, the CPU 21 determines in step 201 whether or not the water temperature switch 11 outputs an ON signal. And if it is an ON signal, CP
U21 sets the abnormality occurrence flag to "1" in step 202, and ends this routine. If the signal is an off signal, the CPU 21 determines in step 203 whether or not the current engine speed is equal to or less than a predetermined flag release speed. If the rotation speed is equal to or less than the flag release rotation speed, the routine ends after resetting the abnormality occurrence flag to “0” in step 204. That is, once the abnormality occurrence flag is set to "1", the set state of the flag is maintained until the engine speed reaches the flag release speed.

If a negative determination is made in step 101 of FIG. 2 (when the water temperature is normal before the timing of t1 in FIG. 4), the CPU 21 proceeds to step 102 and resets the abnormality control flag to “0”. Further, the CPU 21 resets the ignition stop flag to “0” in the subsequent step 103, and then ends this routine. That is, if the water temperature is normal, the CPU 21 proceeds to steps 101 → 102 → 103.
→ Repeat the process in the order of termination, and do not stop ignition.

On the other hand, if the determination in step 101 is affirmative (when the water temperature is abnormal after timing t1 in FIG. 4), CP
U21 performs the processing of the abnormality control after step 104.
That is, first, in step 104, the CPU 21 determines whether or not the abnormality control is being executed according to whether or not the abnormality control flag is set to “1”.

Then, in the first process at the timing t1 in FIG. 4, since the abnormality control flag is "0", a negative determination is made in step 104 and the CPU 21 determines in step 10
Move to 5. The CPU 21 sets the abnormality control flag to "1" in step 105. Thereafter, the CPU 21 proceeds to step 106 and stores the current engine speed in the RAM.
Save to 23. After clearing the ignition stop cycle timer to a predetermined value in step 107, the CPU 21 sets the ignition stop flag to "1" in step 108 and ends the routine. That is, at the timing of t1 in FIG.
The PU 21 performs steps 101 → 104 → 105 → 106
The processing in the order of → 107 → 108 → end is executed only once. Then, the ignition stop is started by setting the ignition stop flag at the timing of t1.

On the other hand, in the second process after the timing of t1 in FIG. 4, both steps 101 and 104 are determined to be affirmative, and the CPU 21 proceeds from step 104 to step 109. In step 109, the CPU 21 determines whether or not the ignition stop process is currently being performed based on whether or not the ignition stop flag is set to "1". At this time, FIG.
In the timings t1 to t2, the determination in step 109 is affirmative, and the CPU 21 proceeds to step 110 to determine whether the ignition has been stopped by the number of times of ignition stop S1 (= 6 ignitions).

Then, in step 110, the number of ignition stops S
If the ignition stop has not been completed, the CPU 21 proceeds to step 111 to determine whether or not the fluctuation of the engine speed during the ignition stop is within a predetermined allowable fluctuation range dne. That is, the current engine speed and the value in the step 10
It is determined whether or not the difference between the saved engine speed (the engine speed immediately before the ignition is stopped) and the saved engine speed is within the allowable fluctuation range dne. Then, if the rotation speed fluctuation is within the allowable fluctuation range dne, the CPU 21 ends this routine as it is. On the other hand, the rotational speed fluctuation is within the allowable fluctuation range dne.
If not, the CPU 21 resets the ignition stop flag to “0” in step 103, and ends this routine. In other words, when the rotation speed fluctuation (drop) is unnecessarily large, by stopping the ignition stop and returning the ignition even before the completion of the ignition stop number S1, the inadvertent decrease in the hull speed is avoided (this operation is not performed). This is indicated by a broken line at the timing of ta in FIG. 4).

As described above, at the timings t1 to t2 in FIG. 4 where the ignition is actually stopped, the CPU 21
Step 101 → 104 → 109 → 110 → 111 →
(103 →) The processing is repeatedly executed in the order of termination. Note that the allowable fluctuation range dne is set to be about 1.5 to 2 times the rotation speed fluctuation (100 rpm) to be generated, and in this embodiment, dne = 150 rpm.

If the ignition has been stopped for the number of times of ignition stop S1 and the determination at step 110 is affirmative (timing at t2 in FIG. 4), the CPU 21 proceeds from step 110 to step 103 and sets the ignition stop flag to "0". Reset to. That is, at the timing of t2 in FIG.
Are steps 101 → 104 → 109 → 110 → 103
→ Execute the process in the order of termination. Then, by resetting the ignition stop flag, normal ignition is restarted from the next ignition cylinder.

On the other hand, after the ignition stop flag is reset at the timing t2 in FIG.
Then, the process proceeds to step 112 to determine whether or not the ignition stop cycle T has elapsed. Then, at the timing of t2 to t3 in FIG.
Terminates this routine. That is, t2 of FIG.
At the timing of t3, the CPU 21
The processing is repeatedly executed in the order of → 104 → 109 → 112 → end.

Further, at time t3 in FIG.
At the timing of, the CPU 21 shifts from step 112 to step 106, and executes steps 106 to 108 described above.
Execute the processing of That is, at the timing of t3 in FIG. 4, the CPU 21 proceeds to step 101 → 104 → 109 →
Processing is performed in the order of 112 → 106 → 107 → 108 → end 1
Execute only once.

After the ignition stop flag is set to "1" again, the above-described processing at the timings t1 to t3 in FIG. 4 is repeatedly executed. As a result, with the occurrence of the water temperature abnormality, a sudden change in engine speed at a predetermined ignition stop cycle T causes a change in engine sound.

As described in detail above, according to the control device of this embodiment, the engine 1 is forcibly stopped in the order of ignition in a predetermined number (ignition stop frequency S1) in accordance with the occurrence of the water temperature abnormality. Causes a sharp change (drop) in the engine speed. The engine noise changes due to the rotation speed fluctuation, so that the driver or the occupant of the ship can easily and surely identify the engine sound as the warning buzzer, and can quickly take measures against the occurrence of the abnormal water temperature. it can. In addition, since this rotation speed fluctuation is specified for a predetermined number of cylinders, an almost constant change in engine sound is always obtained. Further, since the rotation speed fluctuation occurs at predetermined intervals, the influence on the overall engine rotation speed is affected. Is greatly suppressed. As a result, the speed of the hull does not decrease due to an excessive decrease in the rotation speed, and the hull can maintain the speed. In this case, since the engine speed can be maintained, the present control can be performed in the idle speed range (low speed range), and even if a water temperature error occurs in any speed range, the error can be reliably notified to the driver. I can let you know.

In short, the present embodiment is characterized in that a change in engine sound is used as a warning buzzer and that the engine speed (hull speed) can be maintained even when the engine sound changes. That is, as a conventional device, a device that operates a warning buzzer or a warning light in response to occurrence of an abnormality has disadvantages such as a complicated configuration and high cost. In some cases, cylinder reduction control for stopping ignition of some specific cylinders when an abnormality occurs is performed.
There is a demerit that not only a steep decrease in the rotational speed cannot be obtained but also a decrease in the engine rotational speed (a decrease in the hull speed) contrary to the driver's intention may occur. But,
In the present embodiment, the above disadvantages can be solved,
An inexpensive device can be provided by cost reduction.

In the present embodiment, only the case where the water temperature rise is abnormal due to the water temperature switch 11 has been described. However, even in the case where the hydraulic pressure switch 12 shown in FIG. It goes without saying that the same treatment can be performed for each.

In this embodiment, the ignition stop period is defined by the number of ignition stops S1 (the number of ignitions), but may be defined by the rotation fluctuation width instead. That is, the timing at which the ignition is stopped from the execution state of the ignition stop is determined by the decrease width of the engine rotation speed (100 rpm in the six cylinders of this embodiment).
m), it is possible to obtain an effect that an appropriate engine sound is generated and the overall engine speed can be maintained.

Further, although the water temperature switch 11, the hydraulic switch 12, and the exhaust temperature switch 13 output on / off binary signals in response to occurrence of an abnormality, these may be replaced by sensors that output analog data as they are. In this case, C
The PU 21 detects an abnormality according to the level of the analog signal of the sensor, and a signal generating means is configured inside the CPU 21.

Further, the number of times of ignition stop and the cycle of ignition stop can be made variable according to the engine operating conditions (engine speed, etc.) at that time. It can also be embodied in other types of engines (engines other than six-cylinders, automobile engines, etc.). (Second Embodiment) In the first embodiment, the ignition stop control according to one specific abnormality such as the water temperature abnormality by the water temperature switch 11 has been described. However, in the second embodiment, a plurality of abnormalities are distinguished and each abnormality is determined. A case where the control is performed according to the description will be described. Hereinafter, only differences from the first embodiment will be described, and description of the same portions will be omitted.

More specifically, the CPU 21 controls the water temperature switch 1
1. Based on signals from the hydraulic switch 12 and the exhaust temperature switch 13, abnormalities of water temperature rise, oil pressure decrease, and exhaust temperature rise are separately determined (for example, three types of abnormality occurrence flags are set). Then, ignition stop control is performed for each abnormality based on the ignition stop cycle pattern shown in Table 1 below. That is, in the first embodiment, the ignition stop period is always set at the same cycle. However, in the second embodiment, “T1” to “T1” are set.
A cycle of three consecutive steps of "3" is set.

[0047]

[Table 1]

FIG. 5 is a timing chart showing an example of the operation of the ignition stop control in the second embodiment in the case where a water temperature abnormality occurs. 5A shows an abnormality occurrence flag, FIG. 5B shows an ignition stop flag, FIG. 5C shows an ignition stop frequency counter, FIG. 5D shows an ignition stop cycle timer, and FIG. 5E shows an engine speed. The timing of t11 indicates the time when the water temperature abnormality has occurred. According to FIG.
After the timing of, the ignition stop cycle T1 (= 1
), The first ignition stop is performed, and then the second and third ignition stop are performed in the ignition stop cycle T2 (= 0.7 second) and T3 (= 0.5 second). Have been done. That is,
At times t11 to t12, substantially the same engine sound is generated at each timing when the ignition is stopped, but the engine sound is generated in three different periods.

FIG. 6 is a timing chart showing, for each cause of abnormality, fluctuations in the engine speed associated with the operation of the ignition stop control. In FIG. 6, (a) shows the rotation speed fluctuation caused by the water temperature rise abnormality, (b) shows the rotation speed fluctuation caused by the oil pressure drop abnormality, and (c) shows the rotation speed fluctuation caused by the exhaust gas temperature rise abnormality. The timing of t21 indicates the time when each abnormality occurs. According to FIG. 6, after the timing of t21, the rotation speed varies according to the ignition stop cycle pattern of Table 1 for each cause of abnormality. Then, the driver or the passenger can easily identify the cause of the abnormality by distinguishing the generation cycle pattern of the engine sound accompanying the rotation speed fluctuation.

The present invention can be embodied in the following modes in addition to the above embodiments. In each of the above embodiments, the engine sound is always generated by the same method for one specific abnormality (for example, a water temperature abnormality). May be changed. For example, if the water temperature is abnormal, 9
The generation cycle of the engine sound at 5 ° C. (sound pressure level is also possible) and the generation cycle of the engine sound at 100 ° C. are switched. In this case, if the engine sound generation cycle is set to 3 seconds when the water temperature is 95 ° C., and the same generation cycle is set to 1 second when the water temperature is 100 ° C., the driver or the passenger can also identify the abnormal level. it can. Further, if the period is shortened as the level of the abnormality becomes worse, a warning of the abnormality can be issued more reliably.

In each of the above embodiments, the signal generating means is configured to generate a signal when an abnormality is detected. However, in addition to the detection of the abnormality, the failure is embodied in a diagnosis for detecting a failure of an engine component. An engine sound may be generated when a predetermined judgment level is reached. In addition, an engine sound may be generated when a load state such as an engine speed or a running speed of a ship, an automobile, or the like reaches a warning range.

Further, in each of the above embodiments, the ignition is stopped as a specific example of the combustion stopping means. However, the fuel injection may be stopped instead. in this case,
Since a delay occurs due to the timing of the fuel injection, it is necessary to set the fuel injection stop in consideration of the delay.

[0053]

According to the present invention, an excellent effect of being able to reliably notify that the operating condition of the engine has reached a predetermined determination level with a simplified configuration is exhibited. Further, according to the configuration described in claims 2 to 5, favorable driving conditions can be maintained even when the engine sound changes, and furthermore, it is possible to inform the driver or the occupant what is the cause of reaching the determination level. Become.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing a simplified ignition timing control device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a processing routine of ignition stop control executed by a CPU.

FIG. 3 is a flowchart illustrating a water temperature abnormality determination processing routine executed by a CPU;

FIG. 4 is a timing chart showing the operation of ignition stop control in the first embodiment.

FIG. 5 is a timing chart showing the operation of ignition stop control at the time of a water temperature abnormality in the second embodiment.

FIG. 6 is a timing chart showing the operation of ignition stop control in the second embodiment for each cause of abnormality.

[Explanation of symbols]

1 ... 6-cylinder water-cooled engine, 11 ... water temperature switch as signal generating means, 12 ... hydraulic switch as signal generating means, 13 ... exhaust temperature switch as signal generating means, 2
1. CPU as combustion stopping means.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Teruyoshi Ito 1-1-1 Showa-cho, Kariya-shi, Aichi Japan Denso Co., Ltd. (58) Field surveyed (Int. Cl. ⁷ , DB name) F02B 77/08 F02D 17/00-17/04

Claims (5)

(57) [Claims] A signal generating means for generating a signal indicating that the operating condition of the engine has reached a predetermined determination level set in advance; and A control device for an engine, comprising: combustion stopping means for forcibly stopping combustion of a cylinder for a predetermined period so as to change an emitted engine sound, thereby causing a sharp rotation speed fluctuation. 2. The engine control device according to claim 1, wherein the combustion stopping means stops the combustion stop when the rotation speed fluctuation during the execution of the combustion stop exceeds a predetermined allowable range. 3. The engine control device according to claim 1, wherein the combustion stop means defines the combustion stop period by a predetermined number of ignition stop cylinders or a predetermined number of fuel injection stop cylinders arranged in a combustion order. 4. The engine control device according to claim 1, wherein the combustion stopping means repeatedly executes the combustion stop at a predetermined cycle longer than a period during which the combustion stop is executed. 5. The signal generating means generates a plurality of signals for each operation condition to be determined, and the combustion stopping means switches a combustion stopping cycle for each signal in accordance with the signal of the signal generating means. The engine control device according to claim 4.