JP2000054905A - Engine control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To show precisely display for promoting maintenance according to a using condition by changing a predetermined time according to an absentation of a lubricating medium of an internal combustion engine, and displaying judged result on a display means when an operating time of the internal combustion engine is longer than a prescribed time. SOLUTION: An oil level position signal when lubricating oil does not exist on an oil pan is detected as an absentation signal, and it is judged whether lubricating oil is exchanged or not. A value of a lubricating oil exchange time can be changed according to such a history whether the lubricating oil is exchanged or not. A time for exchanging initial lubricating oil is set to a short time, and a time for the later exchanging of lubricating oil can be set to a long time. In the case where it is judged that an operating time of the internal combustion engine has been operated for an integer multiple of a prescribed time, a display is performed for promoting exchange of lubricating oil of an operating panel 50. It is thus possible to perform display for promoting maintenance inspection according to a using condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an engine control system for controlling an internal combustion engine for power generation.

[0002]

2. Description of the Related Art In a rotating portion such as a crankshaft of an internal combustion engine or a sliding portion such as a cylinder and a cylinder wall,
Lubricating oil is always supplied to prevent wear. The lubricating oil repeats a cycle of being sucked up by an oil pump from an oil pan storing the lubricating oil, supplied to a rotating portion or a sliding portion, and then traveling along the wall surface of the internal combustion engine and returning to the oil pan. In the above-mentioned rotating and sliding parts, wear particles and dust are mixed into the lubricating oil, so that the lubricating effect of the lubricating oil gradually decreases. Lubricating oil needs to be changed. In addition, a spark plug that burns the air-fuel mixture sucked into the combustion chamber of the internal combustion engine is difficult to ignite due to accumulation of incomplete combustion products such as carbon on the surface of the ignition part. They need to be replaced regularly.

[0003] In a vehicle-mounted internal combustion engine, the travel distance of a vehicle displayed on a display panel is used as an indication of the operation time of the internal combustion engine, and the timing of replacement and repair of consumable parts such as tires is determined from the travel distance. Therefore, it is possible to determine the timing of replacing the lubricating oil and the spark plug.

[0004]

However, when using an engine for power generation, for example, an engine of a stationary type or an engine for a cogeneration system, maintenance inspections such as replacement of engine parts and the like should be performed based on the period of use. Usually, the operator needs to pay attention to whether or not the usage period has passed a predetermined period, and there is a disadvantage that the operator is burdened.

[0005] The present invention has been made in view of the above points, and an object of the present invention is to provide a control system for an internal combustion engine that can accurately display a message prompting maintenance and inspection.

[0006]

SUMMARY OF THE INVENTION An internal combustion engine control system according to the present invention controls an internal combustion engine based on engine parameters obtained from an internal combustion engine for power generation and includes data for engine control including values of the engine parameters. An engine control system comprising: an engine control unit that issues a command signal for controlling the number of revolutions of the internal combustion engine based on the data signal to the engine control unit. The engine has a lubricating medium detecting unit that detects the presence or absence of a lubricating medium of the internal combustion engine and issues an absent signal to the engine control unit when the lubricating medium is not present. Number-of-absence-integration means for integrating the number of times the Engine operating time integrating means for integrating the operating time of the internal combustion engine based on the engine control data, operating time determining means for determining that the operating time is longer than a predetermined time, and operating time determining means. Display means for displaying a determination result, wherein the predetermined time is changed according to the number of absent.

That is, according to the feature of the present invention, the predetermined time is changed according to the number of times the lubricating medium of the internal combustion engine is absent, and when it is determined that the operation time of the internal combustion engine is longer than the predetermined time, the determination result is obtained. Is displayed on the display means, so that a display prompting maintenance and inspection can be accurately shown according to the usage state of the internal combustion engine. Further, according to another feature of the present invention, in the case of a plurality of internal combustion engines, a display prompting maintenance and inspection of the internal combustion engine whose operating time has been lengthened can be accurately shown.

Further, according to another feature of the present invention, the predetermined time is changed in accordance with the operation state of the self-return type on / off switch, so that the predetermined time can be set based on the judgment of the operator. It is possible to determine the time required for maintenance and inspection based on the predetermined time.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an outline of an engine control system according to the present invention. A combustible gas, for example, natural gas, drawn from a gas supply source 11 and air drawn from an air inlet 12 are mixed in a mixer 13, and the mixed gas is mixed in a combustion chamber of a cylinder 14 of an internal combustion engine 10. (Not shown) and burned, the heat exchange unit 1
The exhaust gas is exhausted from the exhaust port 16 through the exhaust port 5. The combustion of the air-fuel mixture sucked into the combustion chamber of the cylinder 14 drives the rotation of a crankshaft (not shown) of the internal combustion engine 10, and the rotation of the crankshaft is controlled by the rotor of the generator 70 connected to the crankshaft. (Not shown)
Is rotated, and power is generated in the generator 70 by this rotation operation, and a power generation voltage is output from the generator 70.

The cooling medium (coolant) sealed in the cooling pipe 25 is pumped up by the pump 24 and circulates through the cooling pipe 25 via the heat exchangers 21 and 22 and the heat exchanger 23. The above-described cooling medium is supplied to the heat exchange unit 2.
1, the heat generated by the combustion of the air-fuel mixture is absorbed and the heat exchange section 22 absorbs the heat generated from the exhaust gas to cool the internal combustion engine 10.

Further, a heat absorbing medium, eg, water, previously stored in a tank 27 is pumped up by a pump 26 and circulated through a pipe 28 via a heat exchanger 23. This heat absorbing medium absorbs heat from the cooling medium sealed in the cooling pipe 25 in the heat exchanger 23. The above-described device can generate electric power by the operation of the internal combustion engine 10, and can also heat the heat absorbing medium stored in the tank 27 by absorbing heat generated from the internal combustion engine 10.

A group of sensors 31 provided in the internal combustion engine 10, for example, a crankshaft reference position sensor and a coolant temperature sensor, are connected to an engine control unit (hereinafter referred to as an ECU) 32. The ECU 32 includes a sensor group 3
The value of the output signal from 1 is taken as an engine parameter, a control value necessary for controlling the internal combustion engine 10, for example, an ignition timing and a gas supply amount, is calculated, and the internal combustion engine 10 is controlled based on the control value. . ECU3
Reference numeral 2 denotes a system control unit (hereinafter, referred to as SCU) 4 via a communication interface as described later.
0 is connected. By this communication means, data signals such as the rotation speed of the internal combustion engine 10 and the temperature of the cooling medium are transmitted to the EC.
While being supplied from the U 32 to the SCU 40, command signals for setting the engine speed and starting, stopping and decelerating the internal combustion engine 10 are supplied from the SCU 40 to the ECU 32. S
An operation panel 50 described later is connected to the CU 40, and a signal corresponding to an input operation of an operator of the operation panel is transmitted to the SC.
While being supplied to the U40, a signal corresponding to the determination result of the operation state of the internal combustion engine 10 in the SCU40 is supplied from the SCU40 to the operation panel 50.

The SCU 40 includes an inverter control unit (hereinafter, ICU) of an inverter controller 90.
A signal for controlling the inverter controller 90 such as a control signal for ON / OFF operation of contactor switches (hereinafter, referred to as CS) 71 to 75 described later is supplied from the SCU 40 to the ICU 92. On the other hand, a sensor group 91 is provided in the vicinity of output terminals (not shown) of converters (hereinafter referred to as CONV) 76 to 80 to be described later.
A voltage and a current generated from each of the CONVs 76 to 80 are detected, and a detection signal is supplied to an A / D converter 44 of the SCU 40 described later. A sensor group 93 is provided near an output terminal (not shown) of the inverter 81. The sensor group 93 detects a load voltage and a load current generated from the inverter 81, and detects an A / D converter (I / O) of the ICU 92. (Not shown). The ICU 92 uses the detected load voltage and load current values as data signals at predetermined timings, for example, every 200 milliseconds, as SCU4.
It supplies to zero.

The above-described generator 70 is connected to CS71 of the inverter controller 90.
The CS 71 performs an on / off operation in accordance with a control signal issued from the SCU 40, and controls power supply from the generator 70. When a plurality of, for example, four internal combustion engines are mounted, the generators of the internal combustion engines are connected to CS71 to CS74, respectively. Further, the commercial power supply 60 is connected to the CS 75, and the CSs 71 to 75 are selectively connected according to the power required to drive a load (not shown) connected to the inverter controller 90. Thus, the generator and the commercial power supply are selectively connected to supply power to the load.

CS71 to CS75 are CONV76 to CSV, respectively.
And CONVs 76 to 79 convert an AC voltage, for example, three-phase 300 volts, generated from the generator into a DC voltage, for example, 180 volts.
0 converts an AC voltage supplied from the commercial power supply 60, for example, 200 volts for three phases into a DC voltage, for example, 180 volts. The CONVs 76 to 80 are connected to an inverter 81, and the inverter 81 converts a plurality of supplied DC voltages into AC voltages, for example, 100 volts, and outputs the converted voltages. The inverter 81 is connected to a filter 82, and the filter 82 removes a noise component included in the AC voltage generated from the inverter 81 and supplies power to a load (not shown) connected to the inverter controller 90.

FIG. 2 shows a system control unit of the engine control system shown in FIG. The operation panel 50 described above is connected to the input / output bus 42 via the interface circuit 41. The input / output bus 42 is
A data signal or an address signal is input / output to / from the PU 45. In addition, the inverter controller 9
The sensor group 91 provided at 0 is supplied to a multiplexer (hereinafter, referred to as MPX) 43 in the SCU 40. The MPX 43 is a switch that selectively supplies one of output signals from the sensor group 91 to the A / D converter 44 in accordance with a command from the CPU 45 at a predetermined timing. The A / D converter 44
The supplied signal is converted into a digital signal and supplied to the input / output bus 42. A communication interface circuit 49 is connected to the input / output bus 42. The communication interface circuit 49 includes a port (not shown) for serial communication in accordance with a predetermined communication standard, for example, the RS-232C standard.
Of the data signal supplied from the CPU 4 and the CPU 4
5 transmits a command signal issued to the ECU 32 and the ICU 92.

The input / output bus 42 has a ROM 4
6, a RAM 47 and a non-volatile memory 48 are connected. The ROM 46 stores a program for executing the process of integrating the operating time of the internal combustion engine and the process of determining the operating time according to the flowcharts described in FIGS. The nonvolatile memory 48, for example, an EEPROM, stores a flag and a value of the operating time of the internal combustion engine, which will be described later.

FIG. 3 shows an operation panel of the engine control system. The display panel 51 includes an SCU 40 as described later.
And displays the result of the determination of the operating time of the internal combustion engine and the contents stored in the non-volatile memory 48. The emergency stop switch 52 is a switch used when the operator wants to stop the operation of the control system of the internal combustion engine urgently. Also, the reset switch 53
Is a switch used when restarting the control system of the internal combustion engine. The system start-up display LED is a light-emitting diode that indicates that the system is running, and the system emergency stop display LED is a light-emitting diode that lights up when the system is in an emergency stop. Further, the display ON switch is a switch for displaying the display content on the display panel 51, and the display OFF switch is a switch for deleting the display on the display panel 51.

In the following, the engine control system shown in FIG.
It is assumed that all initialization processing such as initialization of variables used in the ICU 92 and activation of a timer described later have been completed. Also, it is assumed that a predetermined number of internal combustion engines, for example, four, are mounted, and each internal combustion engine is operating steadily.

FIG. 4 shows a subroutine for executing a timer process for integrating the operating time of each engine. still,
This subroutine is executed by interruption every predetermined time, for example, every 100 microseconds. First, it is determined whether or not the first internal combustion engine is running (step S11). Whether the internal combustion engine is running or not is determined by EC
If the engine speed supplied from the U32 to the SCU 40 is equal to or higher than a predetermined engine speed, for example, 1000 rpm, it is determined that the engine has started. If the engine speed is lower than the predetermined engine speed, it is determined that the engine has not started. It is. When it is determined that the first internal combustion engine has not started, the counter CO for the first internal combustion engine is determined.
The value of UNTER1 is initialized, for example, set to 0 (step S1
2), it is determined whether or not the second internal combustion engine has been started (step S17). On the other hand, when it is determined that the first internal combustion engine is running, it is determined whether the value of COUNTER1 is greater than a predetermined value C0 (step S13).
When it is determined that the value of COUNTER1 is equal to or less than the predetermined value C0, the value of COUNTER1 is increased by 1 (step S1).
4), proceed to step S17. When it is determined that the value of COUNTER1 is larger than the predetermined value C0, the value of COUNTER1 is initialized (step S15), and the value of the flag F_TIMER1 is set to 1
(Step S16).

By performing the above-described processing, the value of the flag F_TIMER1 can be set to 1 every predetermined time, for example, every minute when the internal combustion engine is running. For example, when this subroutine is executed every 100 microseconds, to set the value of the flag F_TIMER1 to 1 every 1 minute, the predetermined value C0 is set to 60 ×
What is necessary is to set it to 10 ⁴ .

Steps S17-S22 set a flag F_TIMER2 for the second internal combustion engine, steps S23-S28 set a flag F_TIMER3 for the third internal combustion engine, and steps S29-S34. This is a process for setting a flag F_TIMER4 for the engine. FIG. 5 shows a subroutine for integrating the operation time of each engine. This subroutine is executed by interruption processing at predetermined time intervals.

First, a process for determining the replacement time of the cooling medium is executed according to a flowchart shown in FIG. 6 described later (step S41). Next, it is determined whether or not the value of the flag F_TIMER1 described in FIG. 4 is 1 (step S42). If it is determined that the value of the flag F_TIMER1 is not 1, the process proceeds to step S46, and the second internal combustion engine operating time integration process is executed. Meanwhile, the flag
When it is determined that the value of F_TIMER1 is 1, the value of the operating time TIME_SUM1 of the first internal combustion engine is increased by a predetermined value T0, for example, 1 (step S43). This TIME_S
The value of UM1 is stored in a nonvolatile memory, for example, an EEPROM, and does not disappear even when power is not supplied. Next, the value of the flag F_TIMER1 is initialized, for example, set to 0 (step S44), and the operation time determination process of the internal combustion engine described later is executed (step S45). The processing of steps S42 to S45 described above is the operating time integration processing for the first internal combustion engine, and steps S46 to S49 after steps S42 to S45 are the operating time integration processing for the second internal combustion engine. Steps S50 to S53 are the operation time integration processing for the third internal combustion engine, and steps S54 to S57 are the operation time integration processing for the fourth internal combustion engine.

As described in FIG. 4, the flag F_TIME
Since the values of R1 to F_TIMER4 are set to, for example, 1 every minute, the operating time of the internal combustion engine is increased by adding a predetermined value T0, for example, by 1 in steps S43, S47, S51, and S55. , Can be integrated by the predetermined value T0, for example, by one minute. FIG. 6 shows a subroutine for determining the replacement time of the cooling medium.

The flags F_TIMER1 to F_TI determined in FIG.
It is determined whether the value of MER4 is 1 (Step S61)
To S64). If the value of at least one of the flags F_TIMER1 to F_TIMER4 is 1, the value of the cooling medium exchange time TIME_CLNT is set to a predetermined value T0, for example, 1 as in steps S43, S47, S51 or S55 of FIG. It is increased (step S65). Next, it is determined whether the remainder obtained by dividing the value of the cooling medium replacement time _{TIME_CLNT} by the cooling medium replacement time T _CLNT , for example, 6000 hours, is 0 (step S67). When it is determined that the remainder when dividing the value of _{TIME_CLNT} by T _CLNT is 0, that is, the value of the cooling medium replacement time TIME_CLNT is equal to the cooling medium replacement time T _CLNT
If the value is an integral multiple of the following, a display prompting the operation panel 50 to replace the cooling medium, for example, “ERR COOLAN”
T "is displayed (step S67), and the present subroutine ends. On the other hand, if it is determined in step S66 that the remainder obtained by dividing the value of the cooling medium replacement time _{TIME_CLNT} by the cooling medium replacement time T _CLNT is not 0, the subroutine is immediately terminated.

FIG. 7 shows a subroutine for determining the operating time of the internal combustion engine. First, it is determined whether or not the value of the flag F_OILCHG # is 0 (step S71). The # of the flag F_OILCHG # indicates the number of the internal combustion engine, and when the four internal combustion engines are mounted, # is 1 to 4. That is, the flag when the subroutine is executed in step S45 in FIG. 5 is F_OILCHG1, and the flag when the subroutine is executed in step S49 is F_OILCHG1.
The flag when the subroutine is executed in step S53 is F_OILCHG3, and the flag when the subroutine is executed in step S57 is F_OILCHG4. Also, this flag F_O
ILCHG # is a flag that indicates whether or not the lubricating medium, for example, the lubricating oil has been replaced in the past, which is supplied to the rotating and sliding parts of the internal combustion engine as described later. Is a flag which is set to 1 when the exchange has been performed once or more.

It is determined that the value of the flag F_OILCHG # is 0.
If the lubrication oil change time T_{O IL}The value of T_OIL1,
For example, it is set to 20 hours (step S72), and the flag F_
If it is determined that the value of OILCHG # is not 0,
Exchange time T_OILThe value of T_OIL2For example, 100 hours
(Step S73). As mentioned above,
Change the value of lubrication oil change time according to the history of presence or absence
This allows the first lubricating oil change time to be
Between the lubricating oil and the subsequent time
It can be set as long as every 100 hours. Most
By shortening the first lubricating oil change time,
When the running-in of the fuel engine is sufficient, for example, 2
Display that prompts you to change the first lubrication oil after 0 hours
You can do it. Next, the earnings accumulated in FIG.
TIME_SUM #_OILThe remainder when divided by 0
It is determined whether or not there is (step S74). This TIME_S
# Of UM # also indicates the number of the internal combustion engine as described above
In FIG. 5, TIME_SUM1 to TIME_SUM4
It is shown. TIME_SUM # value to T_OILWhen divided by
Is determined to be 0, that is, the internal combustion engine
Operation time of the predetermined time T _OILIt has been determined that
If not, replace the lubricating oil on the operation panel 50.
A prompt is displayed (step S75). For example, in the second
When the operating time of the fuel engine should change the lubricating oil
If it has been reached, it may look like “ERR 2 OIL”
It displays. Then, the flag F_OILERR described later
Is set to 1 (step S76), and step S77 is performed.
Proceed to. On the other hand, in step S74, the value of TIME_SUM # is set to T_OIL
If it is determined that the remainder when divided by is not 0,
The process proceeds to step S77 described in.

Next, it is determined whether or not the remainder obtained by dividing the value of the operation time TIME_SUM # by the spark plug replacement time T _PLG , for example, 1000 hours is 0 (step S77).
If it is determined that the remainder when the value of TIME_SUM # is divided by T _PLG is 0, the operation of the internal combustion engine reaches the timing at which the spark plug needs to be replaced, as in step S75 described above. Display on panel 50 (step S7)
8). On the other hand, if it is determined in step S77 that the remainder obtained by dividing the value of TIME_SUM # by T _PLG is not 0, the process proceeds to step S79.

Next, it is determined whether the remainder obtained by dividing the value of the operation time TIME_SUM # by the catalyst replacement time T _CAT , for example, 40000 hours, is 0 (step S79). TIME
If it is determined that the remainder obtained by dividing the value of _SUM # by T _CAT is 0, it is displayed on the operation panel 50 that the operating time of the internal combustion engine has reached the time to replace the catalyst (step S80). ), End this subroutine. Meanwhile, TIME
If it is determined that the remainder obtained by dividing the value of _SUM # by T _CAT is 0, this subroutine is immediately terminated.

The value of F_OILCHG # described above is also stored in a nonvolatile memory, for example, an EEPROM, and does not disappear even when power is not supplied. FIG. 8 shows a subroutine for setting the lubricating oil replacement time of the internal combustion engine. First, a level sensor (not shown) for detecting the level of the level of the lubricating oil provided in an oil pan (not shown) for storing the lubricating oil of the internal combustion engine is used. By detecting and detecting the liquid level position signal when the lubricating oil is not present in the oil pan as an absent signal, it is determined whether or not the lubricating oil has been replaced (step S81).
The determination as to whether or not the replacement of the lubricating oil has been performed may be made, for example, based on a signal issued from the operation panel when the operator operates the reset switch of the operation panel 50. That is, after the lubricating oil is changed, when the engine control system is restarted, it is determined that the lubricating oil has been changed based on a signal generated by operating the reset switch by the operator. is there. When it is determined that the lubricating oil has not been changed, this subroutine is immediately terminated. On the other hand, when it is determined that the lubricating oil has been changed, it is determined whether or not the value of the flag F_OILERR is 1 (step S82). When it is determined that the value of the flag F_OILERR is not 1, this subroutine ends. flag
When it is determined that the value of F_OILERR is 1, the flag F_OILERR
The value of OILCHG # is set to 1 (step S83), and the flag F
The value of _OILERR # is set to 0 (step S84), and this subroutine ends.

As shown in step S76 of FIG.
F_OILERR is set to 1 when the remainder obtained by dividing the operating time of the internal combustion engine by the lubricating oil replacement time T _OIL becomes 0. Therefore, in the subroutine shown in FIG. 8, when the operation time of the internal combustion engine has not reached the lubricating oil replacement time T _OIL , the lubricating oil _needs to be replaced, such as when the reset switch 53 is pressed carelessly. Even if a signal indicating that the operation has been performed is erroneously issued, the flag F_OI
Unless it is determined that the value of LERR is 1, that is, it is not determined that the remainder obtained by dividing the operating time of the internal combustion engine by the lubricating oil replacement time T _OIL becomes 0, the flag F_OILCHG
The value of # is never set to 1.

In this specification, the term "internal combustion engine" refers to an internal combustion engine including a hybrid engine and the like.

[0033]

As described above, according to the control system for an internal combustion engine according to the present invention, the predetermined time is changed according to the number of times the lubricating medium of the internal combustion engine is absent, and the operating time of the internal combustion engine is shorter than the predetermined time. Since the result of the determination is displayed on the display means when it is determined that the size of the internal combustion engine has increased, it is possible to accurately display a message prompting a maintenance check according to the use state of the internal combustion engine.

According to another feature of the present invention, when a plurality of internal combustion engines are used, a display prompting maintenance and inspection of the internal combustion engine whose operating time has been extended can be accurately shown. Further, according to another feature of the present invention, the predetermined time is changed according to the operation state of the self-return type on / off switch, so that the predetermined time can be set based on the judgment of the operator, and the predetermined time is set. It is possible to determine the time required for maintenance and inspection based on the information.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of an engine control system according to the present invention.

FIG. 2 is a block diagram showing a system control unit of the engine control system shown in FIG.

FIG. 3 is a front view showing an operation panel of the engine control system shown in FIG. 1;

FIG. 4 is a flowchart showing a subroutine for executing a timer process for accumulating the operation time of each engine.

FIG. 5 is a flowchart showing a subroutine for accumulating the operating time of each engine.

FIG. 6 is a flowchart illustrating a subroutine for determining a replacement time of a cooling medium.

FIG. 7 is a flowchart illustrating a subroutine for determining an operation time of an internal combustion engine.

FIG. 8 is a flowchart showing a subroutine for setting an oil replacement time of an internal combustion engine.

[Explanation of symbols]

Reference Signs List 10 internal combustion engine 32 engine control unit (engine control means) 40 system control unit (system control means, engine operating time integrating means, operating time discriminating means, non-existence number integrating means) 50 operation panel (display means) 53 reset switch (on / off) switch)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tsutomu Wakitani 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (Reference) 3G015 AB00 BL01 CA07 EA29 EA32 FC02 3G084 AA00 BA03 BA11 BA17 CA01 CA06 CA07 DA14 EA01 EA02 EA07 EA11 FA00 FA20 FA33 FA36 FA38 3G092 AA01 AB08 AC08 BA03 BA09 BB01 CA01 FA29 FA49 GA01 GA10 GA13 HE01X HE01Z HE08Z HE10Z HF01Z HF19Z 3G093 AA16 BA24 CA01 CB07 DA03 DA03 EA07

Claims (3)

[Claims] An engine control means for controlling the internal combustion engine based on an engine parameter obtained from an internal combustion engine for power generation and for generating engine control data including a value of the engine parameter as a data signal, And a system control unit that issues a command signal for controlling the rotation speed of the internal combustion engine to the engine control unit based on the engine control system.The internal combustion engine detects the presence or absence of a lubricating medium of the internal combustion engine. A lubricating medium detecting unit that issues an absent signal to the engine control unit when the lubricating medium is not present; wherein the system control unit integrates the number of times the absent signal is issued as the absent number. Number-of-times accumulating means, and the operating time of the internal combustion engine is stored in the engine control data. Engine operating time integrating means for integrating based on the operating time, operating time determining means for determining that the operating time is longer than a predetermined time, and display means for displaying a determination result of the operating time determining means, The engine control system according to claim 1, wherein the predetermined time is changed according to the number of absent. 2. The engine control system according to claim 1, wherein said internal combustion engine comprises a plurality of internal combustion engines. 3. The engine control system according to claim 1, wherein the predetermined time is changed in accordance with an operation state of a self-return type on / off switch.