JP2003222609A - Co inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a CO inspection method that can perform reliable judgment without the influence of ambient condition when inspecting, especially by preventing the influence of a humidity factor. <P>SOLUTION: The CO inspection method of an engine which judges CO concentration in exhaust gas defines a judgment value range responding to the ambient condition of the inspection in advance, and measures the ambient condition with detecting the CO concentration when inspecting. Based on the judgment value range responding to the measured ambient condition, the judgment of the CO concentration is performed. As a result, an inspection result with stable reliability can constantly be obtained independently of the ambient condition when inspecting. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CO inspection method for automobile engines such as motorcycles.

[0002]

2. Description of the Related Art In a completion inspection process of a motorcycle, a CO inspection is performed to determine whether a CO concentration in exhaust gas is within a predetermined permissible reference range to check for defective parts or defective assembly. In this CO inspection, the engine of the completed vehicle is driven, the CO concentration in the exhaust gas is measured by the CO sensor, and the detected CO concentration is compared with a predetermined reference judgment value range to determine that the product is non-defective. It is judged as a good product.

[0003]

However, since the CO concentration is affected by ambient environmental conditions such as temperature, atmospheric pressure and humidity, even if the vehicle is the same, if the environmental conditions at the time of inspection change, those factors will be affected. Correspondingly, the CO concentration changes, and a non-defective product is determined as a defective product, or conversely, a defective product is determined as a non-defective product, and the reliability of the inspection is reduced. In particular, in a carburetor engine, drive control corresponding to temperature, atmospheric pressure, humidity, etc. is usually not performed, and in the case of such an engine, these environmental factors greatly affect the reliability of inspection.

In the case of a fuel injection engine using an injector, the injection amount is usually corrected by an ECU (engine control unit) according to the temperature (or intake temperature) and the atmospheric pressure (or intake pressure). Have control. Therefore, the factor of temperature and atmospheric pressure has almost no effect on the CO test, but the factor of humidity is not normally corrected, so that in the case of such an engine, the reliability of the test is affected by the influence of the humidity factor. It depends.

The present invention has been made in view of the above prior art, and an object of the present invention is to provide a CO inspection method which is not affected by the ambient environmental conditions at the time of inspection and which can prevent the influence of humidity factors in particular and make highly reliable determination. To do.

[0006]

In order to achieve the above object, the present invention provides a CO inspection method for an engine for determining CO concentration in exhaust gas, wherein a judgment value range according to environmental conditions of the inspection is set. There is provided a CO inspection method characterized in that the CO concentration is detected at a predetermined time, the environmental condition is measured at the time of inspection, and the CO concentration is judged based on a judgment value range according to the measured environmental condition.

According to this configuration, a normal judgment value standard of CO concentration corresponding to factors of environmental conditions such as temperature, atmospheric pressure and humidity is set in advance, and each factor of these environmental conditions is measured at the time of inspection. A judgment value range serving as a criterion for judging a CO normal value is selected according to the measured value of the environmental factor at the time of inspection, and CO inspection is performed based on the judgment value range at the time of inspection. As a result, stable and highly reliable inspection results can be obtained regardless of the environmental conditions at the time of inspection.

In a preferred configuration example, the engine is equipped with a carburetor, and the factor of the environmental condition is temperature,
It is characterized by including atmospheric pressure or humidity.

According to this structure, in the carburetor engine, the temperature, the atmospheric pressure or the humidity is measured at the time of the inspection, and the judgment value range at the time of the inspection is selected based on the measured data to determine the CO concentration. Inspection reliability is increased.

In another preferred configuration example, the engine is a fuel injection engine that includes an injector controlled by an injection control, and the ECU corrects an injection amount based on data from a sensor provided in the vehicle.
The factor of the environmental condition is a factor other than the object to be detected by the sensor provided in the vehicle.

According to this structure, the EC
In a fuel injection engine in which injection is controlled by U, EC
U performs the basic calculation of the fuel injection amount and its correction calculation based on the detection data from various sensors that detect the operating state of the engine provided in the vehicle. Therefore, the detection factor of the sensor provided in the vehicle does not affect the CO concentration determination regardless of the state at the time of inspection. Therefore, by measuring factors other than the detection object of the sensor equipped in this vehicle at the time of inspection and using the judgment reference value according to the detected value of that factor, stable reliability can be obtained regardless of the environmental conditions at the time of inspection. High test results are obtained.

The present invention further provides a CO inspection method for an engine for determining the CO concentration in exhaust gas, wherein the engine includes an injector that is injection-controlled by an ECU, and the ECU injects in accordance with an operating state. It has a program that calculates the amount and corrects the injection amount based on the humidity. During the inspection, the humidity is measured, the humidity data is sent to the ECU to correct the injection amount, and the CO amount is corrected with this correction.
There is provided a CO inspection method characterized by detecting the concentration and determining the CO concentration based on a certain determination value range.

According to this structure, the EC
In a fuel injection engine in which injection is controlled by U, EC
U performs the basic calculation of the fuel injection amount and its correction calculation based on the detection data from various sensors that detect the operating state of the engine provided on the vehicle side, and the correction calculation of the injection amount based on the humidity data. An arithmetic program in the ECU is formed. Humidity is detected by the humidity sensor at the time of inspection, the detection data is sent to the ECU, and the injection amount is corrected and calculated based on the humidity based on the humidity detection data. By controlling the drive of the engine and inspecting the CO concentration in the exhaust gas with this humidity correction, stable and highly reliable inspection results can be obtained based on a certain criterion regardless of changes in environmental conditions. can get.

[0014]

1 is a block diagram of a CO inspection device according to an embodiment of the present invention. This embodiment is an apparatus for inspecting a carburetor type engine.

An engine 2 of a vehicle 1 such as a motorcycle to be inspected has an intake pipe 3 and an exhaust pipe 4, and a carburetor 5 is provided on the intake pipe 3. The CO inspection device 6 includes a CO sensor 7 for detecting the CO concentration in the exhaust gas discharged from the exhaust pipe 4, an air temperature sensor 8 for detecting the temperature at the inspection position, an atmospheric pressure sensor 9 for detecting the atmospheric pressure, and a humidity. And a humidity sensor 10 that detects the The judgment circuit 11 has a memory 12 and stores an allowable judgment value range defining a normal value of CO concentration. This judgment value range is a value in which a normal value of CO concentration is set according to the temperature, atmospheric pressure and humidity, and is determined in advance by experiments or the like.

When the inspection is carried out, the CO sensor 7 detects the CO concentration in the exhaust gas from the engine, the detection data of the CO concentration is input to the determination circuit 11, and the temperature, pressure and humidity sensors 8 and 9 are used. , 10 are input to the determination circuit 11. The determination circuit 11 selects a determination value range at the time of inspection from the memory 12 based on the detection data of the temperature, atmospheric pressure and humidity, determines whether the CO concentration is normal, and outputs it.

As a factor for defining the judgment value range, the engine temperature or the like may be added in addition to the temperature, atmospheric pressure and humidity. Alternatively, a factor having a small influence on the CO concentration may be omitted.

FIG. 2 is a block diagram of another embodiment of the present invention. This embodiment is an apparatus for inspecting a fuel injection engine.

An engine 14 of a vehicle 13 such as a motorcycle to be inspected has an intake pipe 15 and an exhaust pipe 16, and an injector 17 is mounted facing the intake pipe 15. The engine 14 is drive-controlled by the ECU 18. ECU1
Reference numeral 8 indicates various sensors 19 such as a rotation speed sensor, a throttle opening sensor, a cooling water temperature sensor, and an acceleration sensor for detecting an operating state, and an air temperature sensor (or an intake air temperature sensor) 20 for detecting the temperature and atmospheric pressure of intake air. And an atmospheric pressure sensor (or an intake pressure sensor) 21 are connected. The ECU 18 calculates the basic values of the fuel injection amount and the ignition timing from a map based on the data of the rotational speed and the throttle opening based on the detection data from these sensors, and detects the temperature and atmospheric pressure with respect to the basic values. The final fuel injection amount and the ignition timing are calculated based on the data, and the injector 17 and the ignition coil (not shown) are drive-controlled.

The CO inspection device 22 comprises a CO sensor 23 for detecting the CO concentration in the exhaust gas and a judgment circuit 24 for judging whether the detected CO concentration is within the normal value range.
A humidity sensor 25 is further connected to the determination circuit 24.
The determination circuit 24 includes a memory 26 that stores determination value data that defines a normal value range of CO concentration according to humidity.
During the inspection, the CO sensor 23 measures the CO concentration and the humidity sensor 25 measures the humidity. Judgment circuit 24
Is the CO in the humidity condition at the time of inspection based on the humidity data.
The judgment value is selected from the memory 26, and it is judged whether the detected CO concentration is within the normal value range.

FIG. 3 is a block diagram of still another embodiment of the present invention. This embodiment is a fuel injection type engine as in the example of FIG. 2, and the ECU 18 has a built-in program for correcting the fuel injection amount and the ignition timing based on the humidity data as well as the temperature and atmospheric pressure. There is.
The CO inspection device 27 includes a CO sensor 23 that detects the CO concentration in the exhaust gas and a determination circuit 24 that determines whether the detected CO concentration is within a normal value range. Judgment circuit 24
Has a memory 28 that stores data of a judgment value range for judging whether the CO concentration is within the normal value range. This judgment value range is constant data regardless of environmental conditions.
The CO inspection device 27 is equipped with a humidity sensor 29 either internally or separately.

At the time of inspection, the humidity sensor 29 detects the humidity and sends the humidity data to the ECU 18. The ECU 18 corrects the fuel injection amount and the ignition timing based on the sent humidity data. The injector 17 and the ignition coil (not shown) of the engine 14 are drive-controlled. In this way, by driving the engine in a state of being corrected according to the ambient environment conditions and measuring the CO concentration in the exhaust gas, the CO concentration can be inspected by using the criterion of a certain normal value determination range. .

[0023]

As described above, according to the present invention, a normal judgment value standard of CO concentration corresponding to factors of environmental conditions such as temperature, atmospheric pressure, and humidity is set in advance, and these environmental conditions of these environmental conditions are checked at the time of inspection. Each factor is measured, a judgment value range serving as a judgment standard of a normal CO value is selected according to the measured value of the environmental factor at the time of inspection, and the CO inspection is performed based on the judgment value range at the time of the inspection. As a result, stable and highly reliable inspection results can be obtained regardless of the environmental conditions at the time of inspection.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a configuration diagram of another embodiment of the present invention.

FIG. 3 is a configuration diagram of still another embodiment of the present invention.

[Explanation of symbols]

1: vehicle, 2: engine, 3: intake pipe, 4: exhaust pipe,
5: carburetor, 6: CO inspection device, 7: CO sensor, 8: temperature sensor, 9: atmospheric pressure sensor, 10: humidity sensor, 11: determination circuit, 12: memory, 13: vehicle, 1
4: engine, 15: intake pipe, 16: exhaust pipe, 17: injector, 18: ECU, 19: various sensors, 20:
Air temperature sensor, 21: barometric pressure sensor, 22: CO inspection device,
23: CO sensor, 24: determination circuit, 25: humidity sensor, 26: memory, 27: CO inspection device, 28: memory, 29: humidity sensor.

Claims (4)

[Claims] 1. A CO inspection method for an engine for judging CO concentration in exhaust gas, wherein a judgment value range according to environmental conditions of inspection is predetermined, CO concentration is detected at the time of inspection, and the environmental condition is determined. A CO inspection method characterized by measuring and determining a CO concentration based on a judgment value range corresponding to the measured environmental conditions. 2. The CO inspection method according to claim 1, wherein the engine includes a carburetor, and the factor of the environmental condition includes temperature, atmospheric pressure or humidity. 3. The fuel injection engine, wherein the engine includes an injector that is injection-controlled by an ECU, and the ECU corrects an injection amount based on data from a sensor provided in the vehicle. The CO inspection method according to claim 1, wherein is a factor other than an object to be detected by a sensor provided in the vehicle. 4. A CO inspection method for an engine for determining CO concentration in exhaust gas, wherein the engine includes an injector controlled by an ECU, and the ECU calculates an injection amount according to an operating state. In addition, it has a program that corrects the injection amount based on the humidity, measures the humidity at the time of inspection, sends the humidity data to the ECU, and corrects the injection amount, and the CO concentration is detected and fixed in this corrected state. A CO inspection method characterized in that the CO concentration is judged based on the judgment value range.