JP6196771B2 - Fault diagnosis device for vehicles - Google Patents

Description

  The present invention relates to a failure diagnosis apparatus for a vehicle such as a truck. More specifically, the present invention relates to a vehicle failure diagnosis apparatus that diagnoses the presence or absence of a failure from a deviation between an estimated value of supercharging pressure and a measured value of supercharging pressure in a vehicle equipped with a turbocharger.

The supercharging pressure of a vehicle equipped with a turbocharger is measured by a sensor, etc., and an estimated value of the supercharging pressure is calculated from other parameters (for example, the engine speed and torque), and the measured value of the supercharging pressure (actual value) ) And the estimated value of the supercharging pressure have been proposed in the past for a vehicle failure diagnosis device that diagnoses the presence or absence of a failure.
Here, the estimated value of the supercharging pressure is created by creating a map (including tables and conversion formulas) based on the supercharging pressure measured when various parameters are in a steady state on the test device. The estimated value of the supercharging pressure is calculated using the map created as described above.
Therefore, when executing the above-described failure diagnosis (failure judgment based on the deviation between the measured value and the estimated value of the boost pressure), it is possible to accurately diagnose that the various parameters including the boost pressure are in a steady state. It is a premise. In the prior art, if the engine speed and torque are in a stable state, the estimated value of the boost pressure is calculated assuming that the boost pressure is also in a stable state, and the above-described failure determination is executed.

However, even if the engine speed and torque are in a stable state, the supercharging pressure is not always stable. In other words, whether the engine speed and torque are in a stable state is not directly related to whether the boost pressure is in a stable state.
That is, in the prior art, the estimated value of the supercharging pressure is calculated even though the supercharging pressure is not stable, and based on the deviation between the estimated value of the calculated supercharging pressure and the actually measured value, There is a risk of making decisions.
Therefore, there is a possibility that the accuracy of the failure determination based on the deviation between the estimated value of the supercharging pressure and the actual measurement value according to the prior art is low.

Here, it is determined whether or not the measurement result (supercharging pressure) of the measuring means for measuring the supercharging pressure is stable. If the measurement result of the supercharging pressure is stable, It is also conceivable to perform a failure determination based on a deviation between an actually measured value and an estimated value of the supply pressure.
However, the supercharging pressure is a parameter to be diagnosed, and it is not appropriate in terms of control to use such a parameter for determining stability, which is a premise of control.

As another conventional technique, the boost pressure of a vehicle equipped with a turbocharger is measured, and an estimated value of the boost pressure is obtained from other parameters (for example, engine speed and torque), and the measured value of the boost pressure (actual measurement) The prior art of a vehicle fault diagnosis apparatus that diagnoses the presence or absence of a fault based on the deviation between the value) and the estimated value has been proposed (see, for example, Patent Document 1).
However, the conventional technique (Patent Document 1) does not disclose a specific method for determining whether or not a steady state is present.

JP 2005-155384 A

  The present invention has been proposed in view of the above-described problems of the prior art, and can accurately determine whether or not the supercharging pressure is in a steady state, thereby improving the reliability of failure diagnosis control. The object is to provide a vehicle fault diagnosis device.

As a result of various experiments and researches, the inventor has found that the measured value of the turbine rotation speed (hereinafter referred to as “turbo rotation speed”) and the measured value of the supercharging pressure in the turbocharger exhibit similar characteristics or behavior. I found it. And when the measured value of the turbo rotation speed was in a steady state, it discovered that the measured value of the supercharging pressure was also in a steady state.
The present invention has been proposed based on such knowledge.

According to the present invention, the turbocharger is provided , the engine speed measuring means (1), the torque sensor (2) for measuring the engine torque, the turbo speed sensor (3) for measuring the turbocharger turbine speed, and the supercharging. In the engine failure diagnosis system having a supercharging pressure measuring device (4) for measuring pressure, the engine speed measuring means (1), the torque sensor (2), the turbo speed sensor (3), is connected to the boost pressure measuring device (4) has a control device which supercharging pressure is determined whether a steady-state (B50), the control unit (B50), the parameter of the failure diagnosis steady state has whether the steady state determining means for determining (24) whether the failure determination means for determining whether the failure and (30) to, and the control unit (B50) is the measured engine When the rotational speed, the engine torque and the turbine rotational speed are transmitted to the steady state judging means (24), and the estimated value of the supercharging pressure is determined in the estimation block (B10) based on the engine rotational speed and the engine torque (S1). The steady state determination means (24) compares the input turbo rotation speed, engine rotation speed, and engine torque failure diagnosis parameters with threshold values to determine whether the steady state is stable (S2). ), If it is in a stable steady state, it is determined that a failure diagnosis can be performed based on the deviation between the measured value of the supercharging pressure measuring device (4) and the estimated value (S3). is transmitted to the fault diagnosis unit (30) estimates of the supercharging pressure is determined to supercharging pressure value in the steady state (S4), the failure determining means (30), the parameters of the failure diagnosis including turbo speed Is all Steady state der is, the deviation between the estimated value of the measured value and the boost pressure of the supercharging pressure, compared with a threshold value (S5), the deviation is determined to failure is greater than the threshold (S6 If the deviation is not greater than the threshold value, it is determined that there is no failure (S7) .

Further, according to the present invention , the engine is provided with a turbocharger , the engine speed measuring means (1), the torque sensor (2) for measuring the torque of the engine, and the turbo speed sensor (3) for measuring the turbochar turbine speed. In the engine failure diagnosis system having a supercharging pressure measuring device (4) for measuring a supercharging pressure, the engine speed measuring means (1), the torque sensor (2), and the turbo speed sensor (3) connected to said supercharging pressure measuring device (4) has a control device which supercharging pressure is determined whether a steady-state (B50), the control unit (B50), the parameter of the failure diagnosis the steady state determining means for determining whether or not a steady state (24), and a failure determining means for determining whether a failure (30), said controller (B50) is the measured engine Times Number, engine torque, turbine speed, and supercharging pressure are transmitted to the steady state judging means (24) (S11), and the engine speed, engine torque, and turbine speed are measured by the steady state judging means (24). It is determined from the values whether the engine speed, engine torque, and turbine speed are stable and in a steady state (S12). If the engine speed, engine torque, and turbine speed are in a steady state, measurement is performed. It is determined whether or not the boost pressure is in a steady state (S13). If the measured value of the boost pressure is unstable, it is determined as a failure (S15), and if the boost pressure is not unstable, The measured value of the supercharging pressure is transmitted to the failure diagnosing means (30), the estimated value of the supercharging pressure is determined as the estimated supercharging pressure in the steady state (S4), and the failure judging means (30) Fault diagnosis including rotation speed All steady state der parameter is, the deviation between the estimated value of the measured value and the boost pressure of the supercharging pressure, compared with a threshold value (S5), and the fault is greater than deviation threshold value It has a function of judging (S6) and judging that it is not a failure if the deviation is not larger than the threshold value (S7) .

Further, according to the present invention, the turbocharger comprises an engine speed measuring means (1), a torque sensor (2) for measuring engine torque, and a supercharging pressure measuring device (4) for measuring supercharging pressure. In the engine failure diagnosis system, the engine speed measuring means (1), the torque sensor (2), and the supercharging pressure measuring device (4) are connected, and whether or not the supercharging pressure is in a steady state. a control unit (B50) for determining, said controller (B50) is the steady state determining means for parameters of the failure diagnosis to determine whether a steady state (24), whether failed It has a failure judgment means (30) and for determining, in the engine speed measuring means (1) is estimated block (B10), is connected to the turbo speed map (M11) for estimating the turbo speed, and, prior to When the measured engine speed and engine torque are transmitted to the steady state determination means (24) and the engine speed and the measured engine torque value are measured (S21), the control device (B50), the turbo speed map. In (M11), an estimated value of the turbo rotational speed corresponding to the engine rotational speed measured value and the engine torque measured value is calculated (S22), and the steady state determination means (24) calculates the engine rotational speed measured value and the engine torque measured value. Is determined to be in a stable steady state (S23), if it is in a stable steady state, the measured value of the boost pressure is transmitted to the failure diagnosis means (30) to estimate the boost pressure. There is determined the supercharging pressure value in the steady state (S25), the failure judgment means (30), Ri parameter all steady state der the failure diagnosis including turbo speed, supercharging Measured value of and the difference between the estimated value of the supercharging pressure, compared with a threshold value (S26), the deviation is determined to failure is greater than the threshold value (S28), than the deviation threshold If it is not larger, it has a function of judging that it is not a failure (S27) .

According to the present invention having the above-described configuration, the steady state determination means (24) determines whether failure diagnosis parameters including the turbo speed (for example, engine speed, torque, and turbo speed) are all in a steady state. If the steady state judging means (24) judges that “all the failure diagnosis parameters including the turbo speed are in the steady state”, the supercharging pressure is also in the steady state. It is in.
If the supercharging pressure is in a steady state, the reliability of failure determination based on the deviation between the measured value and the estimated value of the supercharging pressure is improved, and it is accurately diagnosed (determined) whether or not the vehicle has failed. I can do it.

Here, according to the present invention, if the turbo rotational speed measuring device (3) for measuring the turbo rotational speed is provided, the turbo rotational speed is in a steady state according to the measurement result of the turbo rotational speed measuring device (3). It can be determined whether or not there is.
On the other hand, even if the vehicle is not equipped with the turbo rotational speed measuring device (3) or the vehicle in which the turbo rotational speed measuring device is damaged, the control device (B50) can set parameters other than the turbo rotational speed ( For example, if turbo speed estimation means (for example, estimation function means including the turbo speed map M11) for estimating the turbo speed from the measured values of the engine speed and torque) is provided, the turbo speed estimation means ( Using the estimated value of the turbo rotational speed obtained by M11), the steady state judging means (24) can determine whether the turbo rotational speed is in a steady state.
In addition, about a torque, not only a measured value but an estimated value can be used.

1 is a block diagram showing a first embodiment of the present invention. It is a flowchart which shows the control which diagnoses the failure of a vehicle in 1st Embodiment. It is control which diagnoses the failure of a vehicle in 1st Embodiment, Comprising: It is a flowchart which shows the control different from FIG. It is a block diagram which shows 2nd Embodiment of this invention. It is a flowchart which shows the control which diagnoses the failure of a vehicle in 2nd Embodiment. It is a block diagram which shows 3rd Embodiment of this invention. It is a flowchart which shows the control which diagnoses the failure of a vehicle in 3rd Embodiment.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
First, a first embodiment of the present invention will be described with reference to FIGS.
In FIG. 1, a vehicle fault diagnosis apparatus denoted by reference numeral 101 as a whole includes an engine speed measuring means (hereinafter referred to as “engine speed sensor”) 1, a torque sensor 2, and a turbine speed sensor ( (Hereinafter referred to as “turbo rotational speed sensor”) 3, a supercharging pressure sensor 4 for obtaining a measured value of the supercharging pressure, and a control means B 50. Here, instead of the torque sensor 2, it is also possible to use an estimated torque value used for engine control.
The control unit B50 includes an estimation block B10, a steady state determination block B20, and a failure determination unit 30.

The estimation block B10 includes a supercharging pressure map M13 (a device for estimating the supercharging pressure using the supercharging pressure map M13: hereinafter the same), and estimates the supercharging pressure in a steady state using the supercharging pressure map M13. Yes. In the illustrated embodiment, the supercharging pressure map M13 is configured to estimate the supercharging pressure in a steady state from the engine speed and the engine torque.
The steady state determination block B20 includes a first bandpass filter 21, a second bandpass filter 22, a third bandpass filter 23, and a steady state determination unit 24.
Here, each of the band-pass filters 21 to 23 provided in the steady state determination block B20 removes noise and large signal changes included in the input signal transmitted to the steady state determination unit 24. Is provided.

The engine speed sensor 1 is connected to the steady state determination means 24 via the first bandpass filter 21 and the lines L6 and L7. The engine speed sensor 1 is connected to a supercharging pressure map M13 of the estimation block B10 via a line L8.
The torque sensor 2 is connected to the steady state determination means 24 via the second band pass filter 22 and the lines L11 and L12. The torque sensor 2 is connected to a supercharging pressure map M13 of the estimation block B10 via a line L13.
The turbo rotation speed sensor 3 is connected to the steady state determination means 24 via the third band pass filter 23 and the lines L4 and L5.
The supercharging pressure sensor 4 is connected to the failure determination means 30 via a line L14.

The first band pass filter 21 and the steady state determination means 24 are connected via a line L7.
The second band pass filter 22 and the steady state determination means 24 are connected via a line L12.
The third band pass filter 23 and the steady state determination means 24 are connected via a line L5.
The supercharging pressure map M13 in the estimation block B10 is connected to the failure determination means 30 via a line L9.
The steady state determination means 24 in the steady state determination block B20 is connected to the failure determination means 30 via the line L15.

The supercharging pressure map M13 in the estimation block B10 is used to obtain the supercharging pressure in a stable state.
When the engine speed in the failure diagnosis cycle and the torque value in the failure diagnosis cycle are input to the supercharging pressure map M13, the supercharging pressure in a stable state can be estimated.

The steady state determination block B20 has a function of determining whether or not the engine speed, torque, and turbo speed (turbine speed) are in a steady state. Here, the supercharging pressure in the stable state has a strong correlation with the turbo rotational speed in the stable state. If the turbo speed, engine speed, and engine torque are stable, the supercharging pressure is also stable. Therefore, if the steady state determination block B20 determines that the turbo speed, the engine speed, and the engine torque are stable, the supercharging pressure is also stable.
The failure determination means 30 determines the actual value of the supercharging pressure and the supercharging when all the parameters of the failure diagnosis including the turbo rotation number (in the first embodiment, the engine rotation number, torque, and turbo rotation number) are in a steady state. It has a function of calculating a deviation from the estimated pressure value, comparing the calculated deviation with a threshold value, and determining a failure if the deviation is larger than the threshold value.

Next, failure diagnosis control in the first embodiment will be described based on the flowchart of FIG.
2, the engine speed is measured by the engine speed sensor 1, the engine torque is measured by the torque sensor 2, and the turbine speed is measured by the turbo speed sensor 3.
Here, instead of measuring with the torque sensor 2, for example, an estimated engine torque value estimated from the injection amount and the injection timing can be used.
The measured engine speed, engine torque, and turbine speed are removed from the noise and long-cycle elements by the bandpass filters 21 to 23 of the steady state determination block B20, respectively. The frequency for determining the number of stable states is extracted and transmitted to the steady state determination means 24 in the steady state determination block B20.
At the same time, the measured engine speed and engine torque are transmitted to the boost pressure map M13 of the estimation block B10, and the estimated value of the boost pressure in the steady state is determined (calculated) by the map M13.

In step S2, the steady state determination means 24 compares the input engine speed, engine torque, and the amplitude of the waveform obtained by applying a bandpass filter of the turbine speed with a threshold value, and compares the engine speed, engine torque, turbine Judge whether the rotational speed is stable. As described above, if the engine speed, engine torque, and turbine speed are stable, the supercharging pressure is also stable.
If the engine speed, engine torque, and turbine speed are not stable (NO in step S2), it is determined that failure diagnosis cannot be performed based on a deviation between the measured value of the supercharging pressure and the estimated value. And it returns to step S1 without performing a failure diagnosis (step S3). Then, step S1 and subsequent steps are repeated.
If the engine speed, engine torque, and turbine speed are stable (YES in step S2), it is determined that a failure diagnosis can be performed based on the deviation between the measured value of the boost pressure and the estimated value, and step S4. Proceed to

In step S <b> 4, the boost pressure is measured by the boost pressure sensor 4, and the measured value is immediately transmitted to the failure determination means 30.
Here, the estimated value of the supercharging pressure has already been calculated in the process of step S1. If it is determined in step S2 that the turbine rotational speed is stable (step S2 is YES), the supercharging pressure is also stable. Therefore, in step S4, the estimated value of the supercharging pressure determined in the map M13 is determined as the “supercharging pressure estimated value in the steady state (stable state)”.
Then, the process proceeds to step S5.

In step S5, the failure determination means 30 of the control means B50 determines the measured value of the boost pressure (the boost pressure measured by the boost pressure sensor 4 in step S4) and the estimated value of the boost pressure (in step S4). It is determined whether or not the difference (absolute value) (so-called “deviation”) of the determined supercharging pressure in the steady state (stable state) exceeds a threshold value. If the deviation does not exceed the threshold value (NO in step S5), it is determined that there is no failure (step S6), and the process returns to step S1. Then, step S1 and subsequent steps are repeated again.
On the other hand, if the absolute value of the value obtained by subtracting the estimated value of the boost pressure from the measured value of the boost pressure exceeds the threshold value (YES in step S5), it is determined as “failure” in step S7. Although not explicitly shown, when a failure is determined (step S7), it is dealt with by a known and existing technique. Then, the control of the failure diagnosis is finished.

In FIG. 2, the measurement of the supercharging pressure in step S4 may be performed simultaneously with step S1.
When the boost pressure is measured in step S1, the estimated boost pressure value in step S4 can be determined simultaneously with step S2 or can be performed prior to step S2. .

FIG. 3 shows a separate fault diagnosis control which is always performed in parallel with the control related to the fault diagnosis of FIG.
In step S11 of FIG. 3, the engine speed, engine torque, turbine speed, and supercharging pressure are measured by sensors 1, 2, 3, and 4, respectively. Also in the control shown in FIG. 3, it is possible to use an estimated value instead of a measured value for the engine torque.
The measured engine speed, engine torque, and turbine speed are sent to the steady state determination means 24 of the steady state determination block B20 via each of the filters 21, 22, and 23. Further, the measured value of the supercharging pressure measured by the sensor 4 is sent to the failure determination means 30 via the line L14 (see FIG. 1).
Then, the process proceeds to step S13.

In the next step S12, the steady state determination means 24 of the steady state determination block B20 determines that the engine speed, engine torque, and turbine speed are stable (steady state) from the measured values of the engine speed, engine torque, and turbine speed. ) Or not.
If the engine speed, engine torque, and turbine speed are not in a stable state (steady state) (NO in step S12), the process returns to step S11, and step S11 and subsequent steps are repeated again.
On the other hand, if the engine speed, engine torque, and turbine speed are in a stable state (steady state) (YES in step S12), the process proceeds to step S13.

In step S13, the failure determination means 30 determines whether or not the measured boost pressure is in a stable state (steady state).
If the measured boost pressure is in a stable state (steady state) (NO in step S13), it is determined that failure diagnosis control is possible, the process proceeds to step S14, and the process proceeds to steps S4 and S5 in FIG.
On the other hand, if the measured boost pressure is not in a stable state (steady state) (YES in step S13), the engine speed, engine torque, and turbine speed are stable, but only the boost pressure is not stable. Therefore, it is determined that some failure exists. For this reason, the process proceeds to step S15, where it is determined as “failure”, conventionally known processing is performed, and then control of failure diagnosis is finished.

As described above, it is known that when the engine speed, the engine torque, and the turbine speed (turbo speed) are stable, the turbo speed and the supercharging pressure exhibit similar characteristics or behavior.
According to the first embodiment, the supercharging pressure is in a steady state by determining whether the turbo rotation speed, the engine rotation speed, and the engine torque are in a steady state (stable state) by the steady state determination unit 24. Determine whether or not. When the steady state determination means 24 determines that “the turbo speed, the engine speed, and the engine torque are in a steady state”, it is considered that the supercharging pressure is also in a steady state.
In the first embodiment, when the supercharging pressure is in a steady state, whether or not there is a failure is diagnosed based on the deviation between the measured value and the estimated value of the supercharging pressure, so that the reliability of the failure diagnosis is improved. It is possible to accurately determine whether or not the vehicle is out of order.

Next, 2nd Embodiment is described based on FIG. 4, FIG.
The vehicle failure diagnosis apparatus 102 of the second embodiment of FIG. 4 does not include the turbo rotation speed sensor 3 in the vehicle failure diagnosis apparatus 101 of FIG. 1, but instead includes a turbo rotation speed map M11 in the estimation block B10. A filter 12 is provided.
Hereinafter, the vehicle failure diagnosis apparatus 102 of the second embodiment will be described with reference to FIGS. 4 and 5. In the description, differences from the first embodiment shown in FIGS. 1 to 3 will be mainly described.

In FIG. 4, the engine speed sensor 1 is connected via a line L1 to a turbo speed map M11 in the estimation block B10 (an apparatus that estimates the turbo speed using the map M11: hereinafter the same). The torque sensor 2 is connected to the turbo rotation speed map M11 via a line L10. Also in this embodiment, it is possible to use the estimated torque value used for engine control instead of the torque sensor 2.
The turbo rotation speed map M11 is connected to the steady state determination means 24 in the steady state determination block B20 via the line L2, the filter 12 in the estimation block B10, the line L3, and the third band pass filter 23.

The turbo speed map M11 is configured to have a function of estimating the turbo speed at that time from the engine speed and torque.
That is, in the vehicle failure diagnosis apparatus 102 according to the second embodiment, the turbo rotation speed sensor is not provided, but the turbo rotation speed is estimated from the engine rotation speed and the torque, and necessary control is performed based on the estimated turbo rotation speed. Is running.

Next, control of failure diagnosis in the second embodiment will be described based on FIG.
In step S <b> 21 of FIG. 5, the engine speed is measured by the engine speed sensor 1, and the engine torque is measured by the torque sensor 2. Then, the engine speed measurement value and the engine torque measurement value are transmitted to the turbo speed map M11. As described above, instead of measuring the engine torque by the torque sensor 2, an estimated torque value can be used.
In step S22, an estimated value of the turbo rotational speed corresponding to the engine rotational speed measured value and the engine torque measured value is determined (calculated) using the turbo rotational speed map M11.
Although not clearly shown in FIG. 5, in step S22, the engine speed measurement value and the engine torque measurement value are sent to the supercharging pressure map M13, and the estimated value of the supercharging pressure is calculated by the map M13.

In the next step S23, the steady state determination means 24 of the steady state determination block B20 determines whether or not the engine speed measurement value and the engine torque measurement value obtained in step S21 are in a stable state (steady state). Then, it is determined whether or not the estimated value of the turbine rotational speed estimated in step S22 is in a stable state (steady state).
If any of the engine speed measurement value, engine torque measurement value, and turbine speed estimation value is not stable (not in a steady state) (NO in step S23), the measured value and estimated value of the boost pressure are Failure diagnosis based on deviation cannot be performed. Therefore, it is determined that “not diagnosed” in step S24, and the process returns to step S21. Then, step S21 and subsequent steps are repeated again.
On the other hand, if all of the measured engine speed value, the measured engine torque value, and the estimated turbine speed value are in a stable state (steady state) (YES in step S23), the difference between the measured value of the boost pressure and the estimated value It is determined that failure diagnosis can be performed, and the process proceeds to step S25.

In step S25, the boost pressure is measured by the boost pressure sensor 4, and the measured value of the boost pressure is immediately transmitted to the failure determination means 30.
As described above, the estimated value of the supercharging pressure is obtained in step S22. If it is determined in step S23 that the turbine rotational speed (estimated value) is stable (YES in step S23), it is estimated that the supercharging pressure is also stable. As a result, in step S25, the estimated value of the boost pressure that has already been obtained in step S22 is determined as the “supercharge pressure estimated value in the steady state (stable state)”.

In the next step S26, the failure determination means 30 of the control means B50 determines the difference (absolutely) between the boost pressure measurement value measured in step S25 and the “estimated boost pressure value in the steady state” determined in step S25. Value: so-called deviation) and threshold value are compared. Then, it is determined whether or not the deviation exceeds a threshold value.
If the deviation (absolute value obtained by subtracting the estimated value of the boost pressure from the measured value of the boost pressure) does not exceed the threshold value (NO in step S26), it is determined that there is no failure (diagnosis). (Step S27), and the process returns to Step S21. Then, step S21 and subsequent steps are repeated again.
On the other hand, if the deviation exceeds the threshold value (YES in step S26), it is determined as “failure” in step S28. Then, conventionally, necessary measures are taken according to a known technique, and the control of the failure diagnosis is terminated.

In FIG. 5, the measurement of the supercharging pressure in step S25 may be performed simultaneously with step S21.
When the supercharging pressure is measured in step S21, it is possible to determine the “supercharging pressure estimated value in the steady state” in step S25 simultaneously with step S22 or step S23.

According to the second embodiment of FIGS. 4 and 5, the turbo rotational speed is estimated from the engine rotational speed measured value and the engine torque measured value.
Therefore, even if the vehicle is not equipped with a turbo rotation speed sensor, it is determined whether the turbo rotation speed is in a steady state by using the estimated value of the turbo rotation speed based on the turbo rotation speed map M11. Diagnosis can be performed.

  Other configurations and operational effects in the second embodiment shown in FIGS. 4 and 5 are the same as those in the first embodiment shown in FIGS.

Next, a third embodiment will be described based on FIGS.
As shown in FIG. 6, the vehicle failure diagnosis apparatus 103 according to the third embodiment of FIGS. 6 and 7 is different from the vehicle failure diagnosis apparatus 101 of FIG. Is provided.
According to the vehicle failure diagnosis apparatus 103 of the third embodiment, even when the turbo rotation speed sensor 3 fails, the turbo rotation speed is estimated using the measured values of the engine rotation speed and torque, and a turbocharger failure (overload) is detected. It is possible to determine whether there is an abnormality in the supply pressure).
Also in this embodiment, an estimated value of engine torque can be used instead of the measured value of engine torque.

Hereinafter, with reference to FIG. 7, a failure diagnosis method in the vehicle failure diagnosis apparatus 103 of the third embodiment will be described.
In step S30 of FIG. 7, the control means B50 determines whether or not the turbo rotational speed sensor 3 has failed.
Here, it is possible to adopt a conventionally known method for determining whether or not the turbo rotational speed sensor 3 has failed. For example, if the turbo speed sensor 3 is not moving even though the engine is rotating, it can be determined that the turbo speed sensor 3 is out of order. Further, when the measured value of the turbo rotational speed measured by the turbo rotational speed sensor 3 is a value that is more than a predetermined value more than the estimated value of the turbo rotational speed estimated by the turbo rotational speed map M11, the “turbo rotational speed sensor 3 It is also possible to configure so that it is determined that “has failed”.

If the turbo rotational speed sensor 3 is out of order, the process proceeds to step S31 according to the route “YES” in step S30.
On the other hand, if the turbo speed sensor 3 has not failed, the process proceeds to step S41 according to the route of “NO” in step S30.

In the case of following the “YES” route in step S30, the control in steps S31 to S38 is the same as the control step in steps S21 to S28 in FIG. 5 described above for the second embodiment.
In the case of following the “NO” route in step S30, the control in steps S41 to S47 is the same as the control step in steps S2 to S7 in FIG. 2 described above for the first embodiment.
Therefore, the redundant description is saved.

In the illustrated third embodiment, when the turbo speed sensor 3 has not failed, the control device B50 determines whether the measured value of the turbo speed measured by the turbo speed sensor 3 is stable. Thus, it is possible to determine whether or not the supercharging pressure is stable, and to execute a failure diagnosis based on the deviation between the measured value and the estimated value of the supercharging pressure.
On the other hand, if the turbo rotational speed sensor 3 is out of order, the turbo rotational speed map M11 is used to calculate the turbo rotational speed map M11 from the engine rotational speed measured value and the engine torque measured value (or engine torque estimated value) that are parameters other than the turbo rotational speed. Estimate the rotation speed. Then, using the estimated value of the turbo rotation speed, the steady state determination means 24 determines whether or not the turbo rotation speed is in a steady state, thereby determining whether or not the supercharging pressure is stable. Thus, failure diagnosis based on the deviation between the measured value of the supercharging pressure and the estimated value can be executed.

  Other configurations and operational effects in the third embodiment of FIGS. 6 and 7 are the same as those of the first embodiment of FIGS. 1 to 3 and / or the second embodiment of FIGS.

It should be noted that the illustrated embodiment is merely an example, and is not a description to limit the technical scope of the present invention.
For example, as described above, an estimated torque value used for engine control can be used instead of measuring the engine torque with the torque sensor 2.

DESCRIPTION OF SYMBOLS 1 ... Engine speed sensor 2 ... Torque sensor 3 ... Turbo speed sensor 4 ... Supercharging pressure sensor B10 ... Estimation block B20 ... Steady state judgment block 24 ... Steady state Determining means 30 ... Failure determining means B50 ... Control means 101 ... Fault diagnosis device for vehicle

Claims (3)

The turbocharger is provided with a turbocharger, an engine speed measuring means (1), a torque sensor (2) for measuring the torque of the engine, a turbo speed sensor (3) for measuring the turbocharger turbine speed, and a supercharge for measuring the supercharging pressure. In the engine failure diagnosis system having the pressure measuring device (4) , the engine speed measuring means (1), the torque sensor (2), the turbo speed sensor (3), and the supercharging pressure measuring device (4) ) and to be connected, a control device supercharging pressure is determined whether a steady-state (B50), the control unit (B50), the parameter of the failure diagnosis is whether in a steady state the determination to the steady state determining means (24), and a failure determining means for determining whether a failure (30), and the control unit (B50), the engine rotational speed is measured, the engine When the torque and the turbine speed are transmitted to the steady state determination means (24), and the estimated value of the supercharging pressure is determined in the estimation block (B10) based on the engine speed and the engine torque (S1), the steady state The state determination means (24) compares the input turbo speed, engine speed, and engine torque failure diagnosis parameters with threshold values to determine whether or not a stable steady state is obtained (S2). If it is in a steady state, it is determined that a failure diagnosis based on the deviation between the measured value and the estimated value of the supercharging pressure measuring device (4) can be performed (S3). 30), the estimated value of the boost pressure is determined as the estimated value of the boost pressure in the steady state (S4), and the failure determination means (30) has all the parameters of the failure diagnosis including the turbo rotation speed in the steady state. der is, Compares the difference between the estimated value of the measured value and the boost pressure of Kyu圧, with a threshold (S5), the deviation is determined to failure is greater than the threshold (S6), deviation threshold value If it is not larger than this, it has a function which judges that it is not a failure (S7) , The failure diagnosis apparatus for vehicles characterized by the above-mentioned. The turbocharger is provided with a turbocharger, an engine speed measuring means (1), a torque sensor (2) for measuring the torque of the engine, a turbo speed sensor (3) for measuring the turbocharger turbine speed, and a supercharge for measuring the supercharging pressure. In the engine failure diagnosis system having the pressure measuring device (4) , the engine speed measuring means (1), the torque sensor (2), the turbo speed sensor (3), and the supercharging pressure measuring device (4) ) and to be connected, and a control device that supercharging pressure is determined whether a steady state (B50), the control unit (B50), the parameter of the failure diagnosis is whether in a steady state the determination to the steady state determining means (24), and a failure determining means for determining whether a failure (30), said controller (B50), the engine rotational speed measured, the engine torque, The bin rotational speed and the supercharging pressure are transmitted to the steady state judging means (24) (S11), and the steady state judging means (24) calculates the engine rotational speed from the measured values of the engine rotational speed, the engine torque and the turbine rotational speed. And whether the engine torque and the turbine speed are stable and steady (S12). If the engine speed, the engine torque, and the turbine speed are steady, the measured boost pressure is It is determined whether or not it is in a steady state (S13). If the measured value of the supercharging pressure is unstable, it is determined that there is a failure (S15). If the supercharging pressure is not unstable, the supercharging pressure is measured. The value is transmitted to the failure diagnosing means (30), and the estimated value of the supercharging pressure is determined as the estimated supercharging pressure value in the steady state (S4), and the failure determining means (30) is a failure including the turbo rotational speed. All diagnostic parameters are defined Ri state that is compared with the deviation between the estimated value of the measured value and the boost pressure of the supercharging pressure, and a threshold value (S5), the deviation is determined to failure is greater than the threshold value (S6) If the deviation is not greater than the threshold value , the vehicle fault diagnosis device has a function of determining that there is no failure (S7) . In an engine failure diagnosis system comprising a turbocharger and having an engine speed measuring means (1), a torque sensor (2) for measuring engine torque, and a supercharging pressure measuring device (4) for measuring supercharging pressure, A control device (B50) connected to the engine speed measuring means (1), the torque sensor (2), and the supercharging pressure measuring device (4) to determine whether or not the supercharging pressure is in a steady state. has the control unit (B50) is failure judgment means for parameters of the failure diagnosis to determine the steady state determining means for determining whether or not a steady state (24), whether a failure (30 ) and has, at an engine speed measuring means (1) is estimated block (B10), is connected to the turbo speed map (M11) for estimating the turbo rotational speed, and the control unit (B50) is The measured engine speed and engine torque are transmitted to the steady state determination means (24), and when the engine speed and engine torque measurement value are measured (S21), the engine speed is displayed in the turbo speed map (M11). The estimated value of the turbo rotational speed corresponding to the measured value and the engine torque measured value is calculated (S22), and the steady state determination means (24) is in a steady state where the engine rotational speed measured value and the engine torque measured value are stable. (S23) If the steady state is stable, the measured value of the boost pressure is transmitted to the failure diagnosis means (30), and the estimated value of the boost pressure is the boost pressure in the steady state. estimates and determined (S25), the failure determining means (30), Ri parameter all steady state der the failure diagnosis including turbo rotational speed, the estimated measured value and the supercharging pressure of the boost pressure And the deviation between a comparison between the threshold value (S26), the deviation is determined to failure is greater than the threshold value (S28), the deviation is determined not to be a failure if not greater than the threshold value ( S27) A vehicle fault diagnosis apparatus having a function.

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