JPS6027791Y2 - Abnormality detection device for exhaust turbo supercharger - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an exhaust turbo supercharger abnormality detection device for an internal combustion engine.

More specifically, the present invention provides a device configured to detect the boost pressure under specific conditions and confirm the operating state of the exhaust turbo supercharger.

An exhaust turbo supercharger for an internal combustion engine uses the exhaust gas from the internal combustion engine to drive a turbine, and a compressor directly connected to the turbine compresses and supercharges the air. This is to increase the output of the internal combustion engine.

Therefore, an internal combustion engine equipped with a supercharger has more fuel than a non-supercharged engine by the amount of supercharging.

As mentioned above, in a device where fuel and output have increased proportionally, if the turbocharger deteriorates or is damaged, even though the fuel continues to increase, air will not be supplied to match the increase. This can lead to an abnormal rise in exhaust temperature, which can lead to damage to the internal combustion engine.

As mentioned above, in an internal combustion engine equipped with an exhaust turbo supercharger, the operating state of the turbo supercharger has a significant effect on the engine, so the engine is operated while checking the operating state of the turbo supercharger. However, this confirmation device operates by detecting the exhaust temperature at full load, and it is difficult to detect abnormalities in automobile engines that are frequently used in the medium rotation and medium load range. This made it difficult to detect serious failures in the turbocharger.

In other words, conventional turbocharger abnormality detection devices have not been able to reliably and quickly detect the turbocharger abnormality itself.

Furthermore, conventional turbocharger operating state detection devices have to be expensive because they detect the operating state over the entire operating range.

The operating state of the turbocharger is the pressure obtained by this,
That is, it is related to boost pressure, and detection of this boost pressure can be said to be a good means.

However, in an engine that operates under a wide range of loads such as an automobile engine, it is impossible to detect boost pressure in the entire operating range due to the accuracy of the detector, and most of the boost pressure detection data is from the turbo supercharger. It is useless in detecting abnormalities.

The present invention was made in order to eliminate the drawbacks of the prior art described above, and the purpose of the present invention is to determine whether the rotational speed and load of the internal combustion engine are within a certain range, and whether the boost pressure within this range is appropriate or inappropriate. The purpose is to provide a device that can determine whether

In order to achieve the above object, the present invention measures the boost pressure when the engine speed is above a set value or within a certain range, and when the load is above the set value or within a certain range. The present invention is characterized in that a device or abnormality control means, such as an abnormality display device or a fuel reduction device, is activated to detect an abnormality when the boost pressure is below a set value.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of an abnormality detection device for an exhaust turbo supercharger according to the present invention. 1, and the compressor 2 is connected to the intake pipe 4.

Reference numeral 5 denotes a fuel injection pump, to which a solenoid 6 is attached so as to reduce the amount of fuel in response to a signal from a controller 7 when an abnormality occurs.

This fuel injection pump 5 controls the fuel injection ffi by the position of the rack 5a, but the position of this rack 5a is detected by the load rack sensor 8, and the signal thereof is converted by the position-voltage converter. The signal is supplied to the controller 7.

On the other hand, the rotation of the internal combustion engine E is detected by a rotation sensor 10, and its signal is converted by a rotation-voltage converter 11 and supplied to the controller 7.

Further, the boost pressure of the compressor 2 is detected by a boost sensor 12 provided in the intake pipe 4, and the signal thereof is converted by a pressure-voltage converter 13 and sent to the controller 7.
supplied to

FIG. 2 is a conceptual diagram of the internal structure of the controller 7. The signal from the rotation sensor 10 is transmitted to an upper limit confirmation circuit 7b and a lower limit confirmation circuit 7c that constitute a land comparator 7a, and is output from the comparator 7a when within a certain setting range. do.

Similarly, the signal from the rack sensor 8 is supplied to a land comparator 7j composed of an upper limit confirmation circuit 7d and a lower limit confirmation circuit 7e, and is output from the land comparator 7j when the signal is within a certain setting range.

Signals from the two land comparators 7a and 7J are supplied to an AND circuit 7f.

Further, the signal of the boost pressure sensor 12 is transmitted to the comparator 7
g, and when it is above the set value, this comparator 7g
is outputted from the AND circuit 7f, and is supplied to the NAND circuit 7h together with the signal of the AND circuit 7f, and is connected to the AND circuit 7f and the NAND circuit 7.
The signal h is supplied to the AND circuit 71, and this signal controls the solenoid 6 to control the injection amount of the fuel injection pump 5.

Fig. 3 is a diagram showing the basic concept of the operation of the device according to the present invention, and Fig. A shows the relationship between the torque generated by the internal combustion engine and the rotation speed.
Also, diagram B shows the relationship between boost pressure and horsepower.

To explain the operation of the device based on this figure, the land comparator 7a detects whether the engine speed is within the range of E-port.
Check with the land comparator 7j whether the waist and load are within the range of the harness, and if both are satisfied, that is, the third
Check the lower right diagonal shaded area in Figure A using the AND circuit 7f.

In this lower right hatched state, the point ho in the figure indicates the lowest horsepower point, and this point indicates the lowest boost pressure.

The boost pressure during normal operation at this point is set in the comparator 7g (VL) L, and when the boost pressure is lower than this value, an abnormality signal of the exhaust turbo supercharger is issued via the NAND circuit 7h and the AND circuit 71. Since the supercharger is not producing the specified boost pressure for some reason, this abnormal signal operates the solenoid 6 and moves the rack 5a to reduce the amount of fuel injected by the fuel injection pump 5. .

Fig. 4 shows the second embodiment, in which in Fig. 3 A, when the rotational speed is above 0 and the load is in a range of 0 or above, the boost pressure at the lowest horsepower point 0 within that range is shown. This circuit detects whether or not the value exceeds a certain set value, and the circuit is significantly simplified compared to the embodiment shown in FIG.

Table 1 shows the operating signals of the devices shown in FIGS. 2 and 4 individually.

Here, if the rotation speed, load, and boost pressure are within the set range or above the set value, O is shown. Otherwise, × is shown. If the signal is input to the AND and NAND circuit, 11 is shown. Otherwise, O is shown.

The present invention provides an exhaust turbo supercharger that is at least the set value or within the set range when the rotational speed of the internal combustion engine is at least a set value or within a certain range, and when the load is at least the set value or within a certain range. The feature is that the system is configured to generate an abnormal signal when the boost pressure of the system is below a set value.

According to the present invention, the abnormality display device or the fuel reduction device can be operated using the above signal, so that damage to the internal combustion engine can be prevented.

Furthermore, as explained in the embodiments of FIGS. 2 and 4, the detection circuit according to the present invention is significantly simplified, inexpensive, and has the advantage of almost no failures.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of an abnormality detection device for an exhaust turbo supercharger according to an embodiment of the present invention, Fig. 2 is a signal circuit diagram of the device shown in Fig. 1, and Fig. 3 is a signal diagram of the device of the present invention. Figure A shows the relationship between the torque and rotational speed of the internal combustion engine, and Figure B shows the relationship between the boost pressure and horsepower of the exhaust turbo supercharger. FIG. 4 is a signal circuit diagram of the second embodiment, which is a simplified version of the signal circuit diagram of FIG. 2. T...Turbocharger, E...Internal combustion engine, 1...Turbine, 2...Compressor, 5...Fuel injection pump , 5a...
Control rack, 6...Solenoid, 7.
...Controller, 8...Load rack sensor, 10...Rotation sensor, 12...
boost sensor.

Claims (1)

[Scope of utility model registration request] It has a device for detecting the rotation speed of the internal combustion engine, a device for detecting the load of the internal combustion engine, and a device for detecting the boost pressure of the turbo supercharger, and the rotation speed is above a certain set value or within a certain set range. An abnormality detection device for an exhaust turbo supercharger, which is configured to generate an abnormality signal when the boost pressure is below a certain set value when the load is above a set value or within a certain set range.