JP2020037917A - Determination device and blow-by gas treatment device - Google Patents

Abstract

To provide a determination device capable of determining malfunction of a separator accurately, and a blow-by gas treatment device.SOLUTION: A determination device that determines the malfunction of a separator that separates an oil component from blow-by gas generated in an internal combustion engine, comprises a comparison unit that compares a measured flow rate of the blow-by gas passing through the separator with a theoretical flow rate of the blow-by gas, and a determination unit that determines the malfunction of the separator based on the comparison result of the comparison unit.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a determination device and a blow-by gas processing device.

  2. Description of the Related Art Conventionally, there has been known an apparatus capable of determining malfunction of a separator for separating an oil component from blow-by gas generated in an internal combustion engine. For example, in the configuration described in Patent Document 1, the gas pressure before and after the separator is detected, and clogging of the separation member in the separator is determined based on the differential pressure between the gas pressures before and after.

JP-A-2006-223357

  By the way, when a component such as a separating member in the separator is removed, the separator cannot separate the oil component from the blow-by gas, and in this case also, the separator malfunctions. However, in the configuration described in Patent Literature 1, the malfunction of the separator is determined based on the differential pressure between the gas pressures before and after the separator. Therefore, such malfunction cannot be determined. That is, the configuration described in Patent Literature 1 has a certain limit as a device for determining malfunction of the separator.

  An object of the present disclosure is to provide a determination device and a blow-by gas processing device that can accurately determine a malfunction of a separator.

The determination device according to the present disclosure,
A determination device for determining malfunction of a separator that separates an oil component from a blow-by gas generated in an internal combustion engine,
An actual measurement flow rate of the blow-by gas passing through the separator, and a comparison unit that compares the theoretical flow rate of the blow-by gas,
Based on a comparison result of the comparison unit, a determination unit that determines malfunction of the separator,
Is provided.

Blow-by gas processing device according to the present disclosure,
The above determination device;
A blow-by gas pipe through which the blow-by gas flows,
The separator provided in the blow-by gas pipe,
Is provided.

  According to the present disclosure, malfunction of a separator can be accurately determined.

1 is a diagram illustrating an intake and exhaust system of an internal combustion engine to which a blow-by gas processing device according to an embodiment of the present disclosure is applied. It is a flowchart which shows the operation example of the determination control in a blow-by gas processing apparatus.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating an intake and exhaust system of a vehicle 1 to which a blow-by gas processing device 100 according to an embodiment of the present disclosure is applied.

  As shown in FIG. 1, the intake and exhaust system of the vehicle 1 includes an internal combustion engine 2, an intake pipe 3, an exhaust pipe 4, and a blow-by gas processing device 100.

  The internal combustion engine 2 is, for example, a diesel engine mounted on the vehicle 1, and is connected to an intake pipe 3 and an exhaust pipe 4. The intake pipe 3 draws outside air into the internal combustion engine 2. The exhaust pipe 4 exhausts exhaust gas generated in the internal combustion engine 2.

  The blow-by gas processing device 100 includes a blow-by gas pipe 110, a separator 120, a blow-by gas detection unit 130, and a determination device 140.

  The blow-by gas pipe 110 is connected to the internal combustion engine 2 and extends from the internal combustion engine 2 to the outside of the vehicle 1. Thereby, the blow-by gas pipe 110 is configured to discharge blow-by gas generated in the internal combustion engine 2 to the atmosphere.

  The blow-by gas is generated in the crankcase of the internal combustion engine 2 when unburned gas or burned gas that has passed through the gap between the cylinder and the piston leaks from the combustion chamber. The blow-by gas contains an oil component and the like.

  The separator 120 is provided in the blow-by gas flow path in the blow-by gas pipe 110. The separator 120 is provided with components such as a separation member (not shown). The separator 120 separates an oil component from the blow-by gas when the blow-by gas flowing through the blow-by gas pipe 110 passes through a separating member in the separator 120.

  The blow-by gas detection unit 130 is a sensor that detects the flow rate of the blow-by gas that passes through the blow-by gas pipe 110, specifically, the separator 120, and is provided in the blow-by gas pipe 110 before the separator 120.

  The determination device 140 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an input / output circuit (not shown). The determination device 140 is configured to determine malfunction of the separator 120 based on a preset program. The determination device 140 includes a comparison unit 141, a storage unit 142, and a determination unit 143.

  The comparing unit 141 compares the measured flow rate of the blow-by gas passing through the separator 120 with the theoretical flow rate of the blow-by gas.

  The measured flow rate of the blow-by gas is a detection result by the blow-by gas detection unit 130. The theoretical flow rate of the blow-by gas is a flow rate calculated based on the rotation speed of the internal combustion engine 2 and the fuel injection amount. The fuel injection amount is the amount of fuel injected by a fuel injection device (not shown) in the internal combustion engine 2.

  The storage unit 142 stores, for example, a map of the theoretical flow rate of blow-by gas, which is associated with the rotation speed of the internal combustion engine 2 and the fuel injection amount. Note that the storage unit 142 may be external to the determination device 140.

  The comparison unit 141 acquires the rotation speed and the fuel injection amount of the internal combustion engine 2 and reads out the theoretical flow rate corresponding to the acquired rotation speed and the fuel injection amount of the internal combustion engine 2 from the storage unit 142. Then, the comparison unit 141 acquires the measured flow rate, which is the detection result of the blow-by gas detection unit 130, and compares the measured flow rate with the theoretical flow rate.

  The determining unit 143 determines malfunction of the separator 120 based on the comparison result of the comparing unit 141. If the absolute value of the difference between the theoretical flow rate and the actually measured flow rate is greater than a predetermined value, the determination unit 143 determines that the separator 120 is malfunctioning.

  The predetermined value is a value indicating that an error between the theoretical flow rate and the actually measured flow rate is within an allowable range for a desired separation function of the oil component in the separator 120, and may be set arbitrarily.

  For example, when the attachment amount of the oil component on the separation member or the like in the separator 120 increases, the function of separating the oil component in the separator 120 becomes lower than a desired state. In such a case, the actual flow rate of the blow-by gas decreases, and the measured flow rate becomes significantly smaller than the theoretical flow rate. Therefore, the determination unit 143 determines that the separator 120 is malfunctioning.

  Further, the separator 120 may be disposed in the blow-by gas processing apparatus 100 in a state where parts such as a separation member in the separator 120 have been removed or damaged due to replacement work or the like. In this case, the separator 120 cannot function to separate the oil component from the blow-by gas, but when the blow-by gas passes through the separator 120, there is no resistance, so that the flow rate of the blow-by gas increases. As a result, the measured flow rate becomes larger than the theoretical flow rate, and thus the determination unit 143 determines that the separator 120 is malfunctioning.

  As described above, in the present embodiment, the malfunction of the separator 120 can be determined for both the case where the measured flow rate is large and the case where the measured flow rate is small with respect to the theoretical flow rate. Accuracy can be improved. As a result, malfunction of the separator 120 can be accurately determined.

  The predetermined value may be different from the theoretical flow depending on whether the measured flow rate is large or small.

  Next, an operation example of the determination control in the blow-by gas processing apparatus 100 will be described. FIG. 2 is a flowchart illustrating an operation example of the determination control in the blow-by gas processing apparatus 100. The process in FIG. 2 is appropriately executed during the operation of the vehicle 1, for example.

  As shown in FIG. 2, the determination device 140 acquires the measured flow rate of the blow-by gas from the blow-by gas detector 130 (Step S101). Next, the determination device 140 determines whether the absolute value of the difference between the theoretical flow rate and the actually measured flow rate read from the storage unit 142 is greater than a predetermined value (Step S102).

  As a result of the determination, when the absolute value of the difference is equal to or smaller than the predetermined value (step S102, NO), the determination device 140 determines that the separator 120 is not malfunctioning (step S103). On the other hand, when the absolute value of the difference is larger than the predetermined value (step S102, YES), the determination device 140 determines that the separator 120 is malfunctioning (step S104). After step S103 or step S104, the present control ends.

  According to the present embodiment configured as described above, the malfunction of the separator 120 is determined based on the comparison result between the measured flow rate of the blow-by gas and the theoretical flow rate of the blow-by gas. Specifically, when the absolute value of the difference between the theoretical flow rate and the actually measured flow rate is larger than a predetermined value, it is determined that the separator 120 is malfunctioning.

  That is, in the present embodiment, the malfunction of the separator 120 can be determined both when the measured flow rate is larger than the theoretical flow rate and when it is smaller than the theoretical flow rate. As a result, the accuracy of determining the malfunction of the separator 120 can be improved, so that the malfunction of the separator 120 can be accurately determined.

  In particular, in the case of the configuration in which the malfunction of the separator 120 is determined only by the actually measured flow rate, the condition that the separation member in the separator 120 is removed is used as a comparison standard between when the function is normal and when the function is malfunctioning. Does not exist. Therefore, with this configuration, malfunction of the separator 120 cannot be accurately determined.

  However, in the present embodiment, under the situation where the separation member in the separator 120 is removed, the measured flow rate becomes larger than the theoretical flow rate, so that the malfunction of the separator 120 can be determined. That is, in the present embodiment, malfunction of the separator 120 can be determined even in a situation where the separation member in the separator 120 has been removed.

  By the way, in the case of a configuration in which the blow-by gas is discharged to the atmosphere as in the present embodiment, if the separator 120 is malfunctioning, the blow-by gas containing the oil component is discharged to the atmosphere. Therefore, in the case of the above configuration, it is desirable to improve the accuracy of determining the malfunction of the separator 120. In the present embodiment, the accuracy of determining the malfunction of the separator 120 can be improved as described above, and therefore, the above configuration is particularly advantageous.

  In the above-described embodiment, the blow-by gas detector 130 detects the flow rate of the blow-by gas itself. However, the present disclosure is not limited to this. For example, the flow rate of the blow-by gas May be detected. In this case, for example, pressure sensors are provided before and after the separator 120. Then, the determination device 140 calculates the actually measured flow rate of the blow-by gas based on the pressure difference between the former stage and the latter stage of the separator 120 based on the detection result of the pressure sensor.

  Even in this case, the measured flow rate of the blow-by gas can be calculated. The measured flow rate may be calculated in consideration of the temperature of the internal combustion engine 2 and the like in addition to the differential pressure. The temperature should just be provided with the temperature sensor etc. in the location which can detect or estimate the temperature in the blow-by gas pipe 110, such as the internal combustion engine 2 and the blow-by gas pipe 110. Thereby, the measured flow rate can be calculated more accurately.

  Further, in the above embodiment, the theoretical flow rate of the blow-by gas is associated with the rotation speed and the fuel injection amount of the internal combustion engine 2, but the present disclosure is not limited thereto, and the rotation speed of the internal combustion engine 2 and the fuel injection amount are not limited thereto. In addition to the quantity, it may be associated with the temperature of the internal combustion engine 2.

  Further, in the above embodiment, the theoretical flow rate of the blow-by gas is obtained based on the predetermined map, but the present disclosure is not limited to this. For example, the determination device 140 may calculate the theoretical flow rate of the blow-by gas using parameters such as the rotation speed of the internal combustion engine 2 and the fuel injection amount, or may calculate the theoretical flow rate based on a predetermined learning function. It may be calculated.

  Further, in the above embodiment, the blow-by gas pipe 110 is configured to discharge the blow-by gas to the atmosphere. However, the present disclosure is not limited to this, and is configured to return the blow-by gas to the intake pipe 3. May be.

  In addition, each of the above-described embodiments is merely an example of a specific embodiment for carrying out the present disclosure, and the technical scope of the present disclosure should not be interpreted in a limited manner. That is, the present disclosure can be implemented in various forms without departing from the gist or the main features thereof.

  The determination device of the present disclosure is useful as a determination device and a blow-by gas processing device that can accurately determine malfunction of a separator.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Internal combustion engine 3 Intake pipe 4 Exhaust pipe 100 Blow-by gas processing device 110 Blow-by gas pipe 120 Separator 130 Blow-by gas detection unit 140 Judgment device 141 Comparison unit 142 Storage unit 143 Judgment unit

Claims (6)

A determination device for determining malfunction of a separator that separates an oil component from a blow-by gas generated in an internal combustion engine,
An actual measurement flow rate of the blow-by gas passing through the separator, and a comparison unit that compares the theoretical flow rate of the blow-by gas,
Based on a comparison result of the comparison unit, a determination unit that determines malfunction of the separator,
A determination device comprising: The determination unit, if the absolute value of the difference between the theoretical flow rate and the actually measured flow rate is greater than a predetermined value, determines that the separator is malfunctioning,
The determination device according to claim 1. The theoretical flow rate is a flow rate based on a rotation speed and a fuel injection amount of the internal combustion engine.
The determination device according to claim 1. The determination device according to any one of claims 1 to 3,
A blow-by gas pipe through which the blow-by gas flows,
The separator provided in the blow-by gas pipe,
A blow-by gas processing device comprising: A blow-by gas detection unit that detects a flow rate of the blow-by gas passing through the separator,
The blow-by gas processing device according to claim 4. The blow-by gas pipe is configured to discharge blow-by gas that has passed through the separator to the atmosphere.
The blow-by gas processing device according to claim 4.

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