JPH06299916A - Cloggng detector of air cleaner for internal combustion engine - Google Patents

Abstract

(57) [Abstract] [Purpose] By diverting the existing sensor, it is possible to detect clogging without adding a special device and prevent the cost increase due to the addition of the device. [Structure] A clogging detection device includes an air cleaner 3, a throttle valve 5, a throttle opening sensor 7, and a vehicle speed sensor 1.
2, a rotation speed sensor 13, an ECT ECU 14, and an engine ECU 11. The engine ECU 11 stores the reference opening degree of the throttle valve 5 when the engine 1 is in a predetermined output state when the air cleaner 3 is not clogged. When the output state of the engine 1 detected by the vehicle speed sensor 12, the rotation speed sensor 13, and the ECT ECU 14 is a predetermined output state, the engine ECU 11 compares the actual throttle opening degree by the throttle opening degree sensor 7 with the reference opening degree. If the deviation between the two is larger than a predetermined value, it is determined that the air cleaner 3 is clogged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clogging detection device for detecting clogging of an air purifier used in an internal combustion engine such as an automobile.

[0002]

2. Description of the Related Art Conventionally, as a clogging detecting device of this type, for example, Japanese Utility Model Laid-Open No. 57-85126 and Japanese Patent Laid-Open No. 6-85126.
There is a technique disclosed in Japanese Patent Publication No. 2-150064. In the former technique, the filter is structured to be movable in the air flow direction, the amount of movement of the filter is detected, and when the amount of movement is equal to or greater than a predetermined value, it is determined that the filter is clogged. In the latter technique, the negative pressure on the downstream side of the filter in the intake passage is compared with the pressure of the exhaust gas in the exhaust passage, and when the deviation between the two exceeds a predetermined value, the filter It is determined to be clogged. In any of the above-mentioned techniques, attention is paid to the phenomenon that the space between the filter and the throttle valve in the intake passage becomes negative pressure due to filter clogging, and clogging is detected based on the negative pressure value. There is.

[0003]

However, in a general internal combustion engine currently on the market, the intake air temperature sensor is arranged only in the passage downstream of the filter and upstream of the throttle valve to reduce the negative pressure. No sensor or the like for detection is provided. Therefore, when the conventional clogging detection device is applied to the internal combustion engine, a special device has to be added to obtain the negative pressure, which causes a problem of cost increase.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to detect clogging without adding a special device and prevent an increase in cost associated with the addition of the device. An object of the present invention is to provide a clogging detection device for an air cleaner for an internal combustion engine.

[0005]

In order to achieve the above object, the first invention is, as shown in FIG. 1, provided in an intake pipe M2 for introducing intake air into an internal combustion engine M1. In order to control the output of the internal combustion engine M1, the air purifier M3 that captures foreign substances when intake air passes through and the intake pipe M2 are provided on the downstream side of the air purifier M3. A throttle valve M4 for adjusting the amount of intake air to the internal combustion engine M1, an opening degree detection means M5 for detecting the opening degree of the throttle valve M4, and an output state detection for detecting the output state of the internal combustion engine M1. Means M
6, and a reference opening degree storage means M7 that stores a reference opening degree of the throttle valve M4 when the internal combustion engine M1 is in a predetermined output state in which the air purifier M3 is not clogged. When the actual output state of the internal combustion engine M1 by the output state detection means M6 is the predetermined output state, the actual throttle opening degree by the opening degree detection means M5 and the reference stored in the reference opening degree storage means M7. A clogging determination means M8 for comparing the opening degree and determining that the air purifier M3 is clogged when the difference between the two is larger than a predetermined value is provided.

The second invention, as shown in FIG.
Intake pipe M1 for introducing intake air into the internal combustion engine M11
2, an air purifier M13 that captures foreign substances when the intake air passes through in order to clean the intake air, and the intake pipe M12, which is provided downstream of the air purifier M13. In order to control the output of the engine M11, a throttle valve M14 for adjusting the amount of intake air to the internal combustion engine M11, an opening detection means M15 for detecting the opening of the throttle valve M14, and an intake pipe M12. The intake air amount detection means M16, which is provided on the downstream side of the air purifier M13 and detects the intake air amount to the internal combustion engine M11, and the air purifier M13 are not clogged, the internal combustion engine M11. To the throttle valve M14 when the intake air amount to the vehicle reaches a predetermined intake air amount
When the actual intake air amount to the internal combustion engine M11 by the intake air amount detecting means M16 is the predetermined intake air amount, the reference opening storing means M17 stores the reference opening amount of The actual throttle opening is compared with the reference opening stored in the reference opening storage means M17, and when the difference between the two is larger than a predetermined value, the air purifier M13 is clogged. And a clogging determination means M18 for determining.

[0007]

In the first aspect of the present invention, as shown in FIG. 1, when foreign matters such as dust and the like are mixed in the intake air flowing into the intake pipe M2, when these foreign matters pass through the air purifier M3. To
It is captured by the air purifier M3. Clean intake air from which foreign matter has been removed passes through the throttle valve M4 and is taken into the internal combustion engine M1. At this time, the amount of intake air to the internal combustion engine M1 is adjusted according to the opening degree of the throttle valve M4. Further, according to the intake air amount, the internal combustion engine M
1 output is controlled.

In the above-mentioned internal combustion engine M1, as the operating time becomes longer, the amount of foreign matter trapped and accumulated in the air purifier M3 increases. Due to this increase, the air purifier M3
The amount of intake air passing through is reduced. At this time, in order to set the output state of the internal combustion engine M1 to a predetermined output state set in advance,
Throttle valve M
It is necessary to make up for it by adjusting the opening degree of 4. The opening degree of the throttle valve M4 at this time becomes larger as the amount of foreign matter captured by the air purifier M3 increases.

Utilizing this phenomenon, clogging of the air purifier M3 is determined in the first invention as follows.
During operation of the internal combustion engine M1, the opening degree detection means M5 detects the opening degree of the throttle valve M4, and the output state detection means M6 detects the output state of the internal combustion engine M1. When the actual output state of the internal combustion engine M1 by the output state detection means M6 is a predetermined output state,
The actual throttle opening degree by the opening degree detection means M5 and the reference opening degree stored in the reference opening degree storage means M7 are compared by the clogging determination means M8. The reference opening degree is the throttle valve M when the internal combustion engine M1 is in a predetermined output state determined in advance in a state where the air purifier M3 is not clogged.
The opening degree is 4. When the deviation between the actual throttle opening and the reference opening is larger than a predetermined value, the clogging determination means M8 determines that the air purifier M3 is clogged.

As described above, the opening degree detecting means M5 such as the throttle opening degree sensor or the like conventionally provided in the internal combustion engine M1.
Is used, and the clogging determination work is done by software. Further, in the second invention, as shown in FIG.
Foreign matter such as dust in the intake air is captured by the air purifier M13 when passing through the air purifier M13. Clean intake air from which foreign matter has been removed is the throttle valve M1.
4 and is taken into the internal combustion engine M11. At this time, the amount of intake air to the internal combustion engine M11 is adjusted according to the opening degree of the throttle valve M14.

In the internal combustion engine M11, as the operating time becomes longer, the amount of foreign matter trapped and accumulated in the air purifier M13 increases and the amount of intake air passing through the air purifier M13 decreases. At this time, in order to set the intake air amount to the internal combustion engine M11 to a predetermined predetermined intake air amount, it is necessary to compensate for the decrease in the intake air amount due to foreign matter by adjusting the opening degree of the throttle valve M14. The opening degree of the throttle valve M14 at this time becomes larger as the amount of foreign matter captured by the air purifier M13 increases.

Utilizing this phenomenon, clogging of the air purifier M13 is determined as follows in the second invention. While the internal combustion engine M11 is operating, the throttle valve M1
The opening degree of No. 4 is detected by the opening degree detection means M15, and the amount of intake air that passes through the downstream side of the throttle valve M14 and is introduced into the internal combustion engine M11 is detected by the intake air amount detection means M16. When the actual intake air amount of the internal combustion engine M11 by the intake air amount detection means M16 is a predetermined predetermined intake air amount, the opening degree detection means M
The actual throttle opening by 15 and the reference opening stored in the reference opening storage means M17 are the clogging determination means M1.
8 compared. The standard opening is the air purifier M13.
Is the opening degree of the throttle valve M14 when the intake air amount into the internal combustion engine M11 becomes a predetermined intake air amount in a state where is not clogged. When the deviation between the actual throttle opening and the reference opening is larger than a predetermined value, the clogging determination means M18 determines that the air purifier M13 is clogged.

Therefore, also in the second aspect of the invention, the existing opening degree detecting means M15 is diverted and the clogging determination work is performed by software.

[0014]

【Example】

(First Embodiment) A first embodiment of the first invention will be described below with reference to FIGS.

FIG. 2 is a schematic configuration diagram of the clogging detection device of this embodiment. A gasoline engine 1 is mounted on the vehicle as an internal combustion engine, and an automatic transmission (not shown) is drivingly connected to the output side of the gasoline engine 1. An intake pipe 2 for guiding air to the combustion chamber is connected to the engine 1. An air cleaner 3 as an air purifier is attached to the upstream end (the left end in FIG. 3) of the intake pipe 2. A filter (element) 4 is mounted in the case of the air cleaner 3, and the filter 4 captures foreign matter such as dust when the intake air passes through.

A butterfly type throttle valve 5 is arranged in the intake pipe 2 downstream of the air cleaner 3. The throttle valve 5 is rotatably supported by the intake pipe 2 by a support shaft 6. The throttle valve 5 is for adjusting the amount of intake air flowing through the intake pipe 2 in order to control the output of the engine 1. Throttle valve 5
A throttle opening sensor 7 as an opening detecting means is provided in the vicinity of. The throttle opening sensor 7 is mechanically connected to the support shaft 6 of the throttle valve 5, and converts the rotational displacement (throttle opening θ) of the support shaft 6 into an electric signal.

On the downstream side of the throttle valve 5 in the intake pipe 2, a movable vane type intake air amount sensor 8 is attached. The intake air amount sensor 8 of this type detects the intake air amount Q by the position where the force for opening the vane (rotating plate) and the return spring balance when the intake air passes.

The instrument panel of the vehicle is provided with a warning light 9 for informing the driver that the filter 4 of the air cleaner 3 is clogged. The warning light 9 is electrically connected to the output side of an electronic control unit (engine ECU) 11 for engine control. The engine ECU 11 constitutes reference opening storage means and clogging determination means. The throttle opening sensor 7 and the intake air amount sensor 8 are connected to the input side of the engine ECU 11. In addition, the vehicle speed sensor 12, the rotation speed sensor 13, and an electronic control unit (ECT) for controlling the automatic transmission are provided on the input side of the engine ECU 11.
ECU) 14 is connected. These vehicle speed sensors 1
2, the rotation speed sensor 13 and the ECT ECU 14 constitute an output state detecting means for detecting the output state of the engine 1.

The vehicle speed sensor 12 is built in a speedometer (not shown). The magnetic flux of the permanent magnet driven by the speedometer cable is detected by the reed switch and a vehicle speed signal (vehicle speed V) of 4 pulses per rotation is detected. To detect. The rotation speed sensor 13 is built in the distributor and includes a timing rotor having a large number of protrusions at equal angles, and one pickup coil. The rotation speed sensor 13 detects the engine rotation speed NE based on the pulse signal output from the pickup coil according to the rotation of the timing rotor. The ECT ECU 14 drives the solenoid of the automatic transmission to determine whether or not to lock up, and outputs a lock-up signal to the engine ECU 11 when a condition for lock-up is satisfied.
Here, lockup is detected in a vehicle equipped with an automatic transmission if the engine 1 is rotating at a predetermined rotation speed but is not locked up, the engine speed NE and the vehicle speed V ( This is because there is no one-to-one correspondence with the wheel rotation speed).

The engine ECU 11 includes the above-mentioned throttle opening sensor 7, vehicle speed sensor 12, rotation speed sensor 13,
The state of clogging of the air cleaner 3 is determined based on various signals from the ECT ECU 14, and the operation of the warning light 9 is controlled according to the determination result. In order to determine the clogging, the memory (ROM) of the engine ECU 11 is in a state where the air cleaner 3 is not clogged, that is, when the air cleaner 3 is not used, the engine 1 enters a predetermined output state. The reference opening degree θa of the throttle valve 5 at this time is stored in advance (during vehicle manufacture). As the predetermined output state, for example, the engine speed NE is 2400 r
An example is a state in which the vehicle speed V is 100 pm, the vehicle speed V is 100 Km / h, and the automatic transmission is locked up.

The above-mentioned throttle opening sensor 7,
Vehicle speed sensor 12, rotation speed sensor 13, ECT ECU14
Is not newly added to determine the clogging state of the air cleaner 3, but performs fuel injection control of the engine 1, ignition timing control, selection of a shift pattern of the automatic transmission, lockup control, etc. It was originally provided on the vehicle. In this embodiment, these various sensors are used for detecting clogging of the air cleaner 3.

During operation of the engine 1 equipped with the above clogging detection device, if foreign matter such as dust is mixed in the intake air flowing into the intake pipe 2, these will pass through the air cleaner 3. At that time, it is captured by the filter 4 of the air cleaner 3. Clean intake air from which foreign matter has been removed passes through the throttle valve 5 and is taken into the engine 1. At this time, the amount of intake air to the engine 1 is adjusted according to the opening degree of the throttle valve 5. Further, the output of the engine 1 is controlled according to the intake air amount.

In the engine 1 described above, as the operating time becomes longer, the amount of foreign matter captured and accumulated by the air cleaner 3 increases. This increase reduces the amount of intake air passing through the air cleaner 3. At this time, in order to set the output state of the engine 1 to a predetermined output state, it is necessary to compensate for the decrease in the intake air amount due to foreign matter by adjusting the opening degree of the throttle valve 5. At this time, the opening degree of the throttle valve 5 increases as the amount of foreign matter captured by the filter 4 of the air cleaner 3 increases.

Next, the operation and effect of the clogging detection device which utilizes the above phenomenon will be described. The flowchart of FIG. 4 shows a “clogging detection routine” for detecting clogging of the air cleaner 3 among the processes executed by the engine ECU 11, and is started at a predetermined timing.

Each processing of the clogging detection routine is executed based on the counting operation of the counter. The counter is
The number of times of reading the throttle sensitivity θ read during the period in which the engine 1 is in the predetermined output state is counted. The count value C obtained by the counting operation corresponds to the time during which the engine 1 is in the predetermined output state. The count value C is set to "0" as an initial value when the ignition switch is turned on to start the engine.

When the processing of this routine is started, the engine ECU 11 first determines in step 101 the vehicle speed sensor 1
The vehicle speed V based on 2 and the engine speed NE based on the speed sensor 13 and the presence or absence of a lockup signal from the ECT ECU 14 are read.

Subsequently, the engine ECU 11 executes step 1
In 02 to 104, it is determined whether the output state of the engine 1 is the predetermined state. In step 102, it is determined whether the vehicle speed V is 100 km / h. In step 103, it is determined whether the engine speed NE is 2400 rpm. Further, in step 104, it is determined whether or not the lockup signal is output from the ECT ECU 14.

If any one of the determination conditions of steps 102 to 104 is not satisfied, the engine ECU 11 determines the output state (vehicle running state) of the engine 1 at that time for determining the clogging state of the air cleaner 3. If not, the count value C of the counter is reset to "0" in step 105. Further, the engine ECU 11
In step 106, a signal for turning off the warning light 9 is output, and the subsequent processing is temporarily terminated.

When all the determination conditions in steps 102 to 104 are satisfied, the engine ECU 11 determines in step 10
7, the throttle opening θ at that time is read by the throttle opening sensor 7, and this is stored in the memory. Next, the engine ECU 11 increments the count value C of the counter by "1" in step 108. Immediately after the determination conditions of steps 102 to 104 are satisfied, the count value C becomes "1".

Subsequently, the engine ECU 11 executes step 1
At 09, it is determined whether the count value C is a predetermined value A or more. The predetermined value A is a value corresponding to "10 seconds", for example. When the count value C is less than the predetermined value A (C <A), the engine ECU 11 causes the engine ECU 11 to execute the step 10
The processes of 1 to 108 are repeated. Here, if even one of the determination conditions of steps 102 to 104 is not satisfied before the count value C becomes equal to or greater than the predetermined value A, the clogging of the air cleaner 3 is not detected.

When the determination condition of step 109 is satisfied (C ≧ A), the engine ECU 11 determines that the output state (running state) of the engine 1 at that time is a state for determining clogging of the air cleaner 3. Then step 1
Move to 10. Engine EC in step 110
U11 finds the average value of the throttle opening θ stored in step 107, and corrects the average value by the outside air temperature, atmospheric pressure, engine cooling water temperature, and the like. Here, the value obtained by the correction is set as the correction opening θb.

Next, the engine ECU 11 executes step 11
In 1, the reference opening θa is subtracted from the corrected opening θb, and the subtraction result is defined as the deviation α. As described above, the reference opening θa is obtained when the air cleaner 3 is not clogged (when the new air cleaner 3 is used).
Is the opening degree of the throttle valve 5 when is a predetermined output state.

Subsequently, the engine ECU 11 executes step 1
At 12, it is determined whether the deviation α is larger than a preset value B. If the deviation α is less than or equal to the set value, the engine ECU 11 determines that the clogging of the air cleaner 3 is tolerable, and step 10
At 6, a signal for turning off the warning light 9 is output. If the deviation α is larger than the set value, the engine ECU 1
In No. 1, the clogging of the air cleaner 3 exceeds the allowable level, and it is judged that the filter 4 needs to be replaced or cleaned, and a signal for turning on the warning light 9 is output in step 113. . And step 1
After executing the processing of 06 or 113, the engine ECU 11 once ends the subsequent processing.

As described above, in this embodiment, the reference opening degree θa of the throttle valve 5 when the engine 1 is in the predetermined output state when the filter 4 of the air cleaner 3 is not clogged is stored. When the actual output state of the engine 1 is the predetermined output state (step 1
When all the determination conditions of 02 to 104 are satisfied), the actual throttle opening (corrected opening θb) by the throttle opening sensor 7 is compared with the reference opening θa (step 1
11) If the deviation α between the two is larger than a predetermined value (set value B), it is determined that the air cleaner 3 is clogged (step 112).

For example, as shown in FIG. 5, when the filter 4 is new and the filter transmittance is 100%, the deviation α becomes "0". As the operating time of the engine 1 increases, the filter transmittance decreases and the deviation α increases. If the deviation α is equal to or less than the set value B, the warning lamp 9 continues to be turned off. When the deviation α becomes larger than the set value B at the timing t1, the warning lamp 9 is turned on. This lighting allows the driver to know the necessity of replacing or cleaning the filter 4.

In this way, in this embodiment, the clogging determination work is performed by software. For this determination, the throttle opening sensor 7 provided in the engine 1 has been diverted, and no special sensor, device, or the like has been added. Therefore, unlike the prior art in which a special device has to be added to obtain the negative pressure, clogging can be detected in this embodiment without any special cost increase.

Further, in this embodiment, the average value of the throttle opening is obtained only when the predetermined output state continues for a certain time,
Since the clogging of the air cleaner 3 is determined using the value (correction opening θb), it is possible to eliminate the error when the predetermined output state is instantaneously reached. (Second Embodiment) Next, a second embodiment of the second invention will be described with reference to FIG. FIG. 6 shows a clogging detection routine corresponding to FIG. In the present embodiment, the intake air amount sensor 8 in FIG. 3 is used as the intake air amount detecting means, and the detection signal (intake air amount Q) is used for clogging detection. In addition, with the air cleaner 3 not clogged, the intake air amount Q to the engine 1
Stores a reference opening degree θa of the throttle valve 5 at which the predetermined intake air amount Qa becomes a predetermined value. The other structure is the same as that of the first embodiment. Note that, in FIG. 6, the same steps as those in FIG. 4 are denoted by the same step numbers, and description thereof will be omitted.

When the processing of this routine is started, the engine ECU 11 reads the intake air amount Q by the intake air amount sensor 8 in step 101a. This process replaces the process of reading the vehicle speed V, the engine speed NE, and the presence / absence of a lockup signal in step 101 of FIG.

Subsequently, the engine ECU 11 executes step 1
02a, the intake air amount Q is the predetermined intake air amount Q
It is determined whether it is a. This process replaces the determination process of steps 102 to 104 in FIG. If the intake air amount Q does not match the predetermined intake air amount Qa, the engine ECU 11 determines that the output state (running state) of the engine 1 at that time is not a state for determining clogging of the air cleaner 3, and step 105 , 106 is executed.

Further, the intake air amount Q is the predetermined intake air amount Qa.
If it matches with, the engine ECU 11 determines that the state of the engine 1 at that time is a state for determining the clogging state of the air cleaner 3, and steps 107 to 11 are performed.
Process 3 is executed. In particular, in step 111, the deviation α between the corrected opening θb and the reference opening θa is obtained, and in step 112, it is determined whether or not the deviation α is larger than a preset value B. If the deviation α is larger than the set value B, it is determined that the clogging state of the air cleaner 3 exceeds an allowable level, and a signal for turning on the warning lamp 9 is output in step 113.

As described above, in this embodiment, the reference opening degree θa of the throttle valve 5 when the intake air amount Q to the engine 1 becomes the predetermined intake air amount Qa when the air cleaner 3 is not clogged. I remember. Then, when the actual intake air amount Q by the intake air amount sensor 8 is the predetermined intake air amount Qa, the actual throttle opening θ is compared with the reference opening θa, and the deviation between them is set to a predetermined value ( When it is larger than the set value B), it is determined that the air cleaner 3 is clogged.

Therefore, according to this embodiment, as in the first embodiment, it is possible to detect clogging without adding a special device and without increasing the cost. The first and second inventions are not limited to the configurations of the respective embodiments, and may be arbitrarily modified within the scope not departing from the spirit of the invention, for example, as follows.

(1) In the first and second embodiments, a movable vane type sensor is used as the intake air amount sensor 8, but instead of this, a Karman vortex is generated in the intake pipe,
A Karman vortex sensor that detects the number of vortices generated in a unit time by ultrasonic modulation may be used. Alternatively, a hot wire sensor may be used in which a platinum hot wire heated by flowing an electric current is arranged in the intake pipe, and the platinum hot wire is cooled by the intake air flow to change the electric resistance.

(2) In the first embodiment, when the output state of the vehicle becomes one specific state (predetermined output state) (when all the determination conditions of steps 102 to 104 in FIG. 4 are satisfied). I tried to judge the clogging only,
A plurality of states may be set as the predetermined output state.
In this case, it is preferable to perform different correction for each set output state.

(3) In the first and second embodiments, the clogging detection device is applied to the engine 1 to which the automatic transmission is drivingly connected, but this is applied to the engine 1 to which the manual transmission is drivingly connected. You may apply. In the case of the first embodiment, the process of step 104 in FIG. 4 is unnecessary.

(4) In the first embodiment, the clogging is judged when the predetermined output state continues for 10 seconds, and in the second embodiment, the state of the predetermined intake air amount Qa continues for 10 seconds. Although the determination of the clogging is performed in the above, the duration of these may be changed as appropriate.

(5) In the first embodiment, as the predetermined output state of the engine 1, the vehicle speed V is 100 Km / h, the engine speed NE is 2400 rpm, and the drop-up signal is output. Was set,
These are only examples and are preferably adapted according to the vehicle.

(6) After each step 112 in FIGS. 4 and 6, the deviation α between the corrected opening θb and the reference opening θa is “0”.
It is also possible to add a process for determining whether the filter 4 is smaller than the above, and to detect whether the filter 4 is not attached or damaged when this determination condition is satisfied. This is because, when the filter 4 is not attached or is damaged, the inflow resistance is eliminated, so that the correction opening θb becomes smaller than the reference opening θa in the predetermined output state, and the deviation α is larger than 0. Because it becomes smaller.

(7) Instead of the warning light 9 of the first and second embodiments, a buzzer may be used to notify the driver of the clogging.

[0050]

As described above in detail, in the first aspect of the invention, the reference opening degree of the throttle valve when the internal combustion engine is in the predetermined output state when the air purifier is not clogged is stored. is doing. Then, when the actual output state of the internal combustion engine is the predetermined output state, the actual throttle opening and the reference opening are compared, and if the deviation between the two is larger than a predetermined value, the air purifier is It is determined that it is clogged. As described above, since the existing sensor is diverted and the determination work is performed by software, it is possible to detect the clogging without adding a special device and prevent the cost increase due to the addition of the device.

In the second aspect of the invention, the reference opening of the throttle valve when the amount of intake air to the internal combustion engine reaches a predetermined intake air amount in a state where the air purifier is not clogged is stored. is doing. Then, when the actual intake air amount to the internal combustion engine is the predetermined intake air amount, the actual throttle opening and the reference opening are compared, and when the deviation between the two is larger than a predetermined value, the air is It is determined that the purifier is clogged. Therefore, according to the second aspect of the present invention as well, it is possible to detect clogging without adding a special device and prevent an increase in cost due to the addition of a device.

[Brief description of drawings]

FIG. 1 is a conceptual configuration diagram of a first invention.

FIG. 2 is a conceptual configuration diagram of a second invention.

FIG. 3 is a schematic configuration diagram of a clogging detection device for an air cleaner in a first embodiment embodying the first invention.

FIG. 4 is a flowchart illustrating a clogging detection routine executed by an engine ECU in the first embodiment.

FIG. 5 is a timing chart showing the relationship between the deviation between the corrected opening and the reference opening, the filter transmittance, and the lighting state of the warning light in the first embodiment.

FIG. 6 shows a second embodiment embodying the second invention,
6 is a flowchart illustrating a clogging detection routine executed by an engine ECU.

[Explanation of symbols]

1 ... Engine as internal combustion engine, 2 ... Intake pipe, 3 ... Air cleaner as air purifier, 5 ... Throttle valve,
7 ... Throttle opening sensor as opening detecting means, 8 ...
Intake air amount sensor as intake air amount detecting means, 11 ...
Engine ECU as reference opening storage means and clogging determination means, 12 ... Vehicle speed sensor forming a part of output state detecting means, 13 ... Rotation speed sensor forming a part of output state detecting means, 14 ... Output state ECT ECU constituting a part of the detecting means, θ ... throttle opening, θa ... reference opening,
Q: intake air amount, Qa: predetermined intake air amount, α: deviation, B
… Set value

Claims (2)

[Claims] 1. An air purifier provided on an intake pipe for introducing intake air into an internal combustion engine, for purifying the intake air, the air purifier capturing foreign matter when the intake air passes, and the intake pipe of the intake pipe. A throttle valve that is provided downstream of the air purifier and that controls the output of the internal combustion engine to adjust the amount of intake air to the internal combustion engine, and an opening detection that detects the opening of the throttle valve. Means, an output state detecting means for detecting an output state of the internal combustion engine, and a reference opening of the throttle valve when the internal combustion engine is in a predetermined output state in a state where the air purifier is not clogged. A reference opening degree storage means for storing a degree, an actual throttle opening degree by the opening degree detection means when the actual output state of the internal combustion engine by the output state detection means is the predetermined output state, and And a clogging determination means for determining that the air purifier is clogged when comparing the reference opening degree stored in the quasi-opening degree storage means with each other and a deviation between them is larger than a predetermined value. A clogging detection device for an air cleaner for an internal combustion engine, which is characterized in that 2. An air purifier which is provided in an intake pipe for introducing intake air into an internal combustion engine, and which cleans the intake air, the air purifier capturing foreign matter when the intake air passes, and the intake pipe. A throttle valve that is provided downstream of the air purifier and that controls the output of the internal combustion engine to adjust the amount of intake air to the internal combustion engine, and an opening detection that detects the opening of the throttle valve. Means, an intake air amount detection means provided downstream of the air cleaner of the intake pipe for detecting the amount of intake air to the internal combustion engine, and the air cleaner not clogged, Reference opening degree storage means for storing a reference opening degree of the throttle valve when the intake air quantity to the internal combustion engine reaches a predetermined predetermined intake air quantity, and actual intake air to the internal combustion engine by the intake air quantity detecting means. Amount is above When the intake air amount is constant, the actual throttle opening degree by the opening degree detection means is compared with the reference opening degree stored in the reference opening degree storage means, and the deviation between them is larger than a predetermined value. In this case, there is provided a clogging determination means for determining that the air purifier is clogged, and a clogging detection device for an air purifier for an internal combustion engine.