JPH05321687A - Oil feeder for exhaust turbo supercharger - Google Patents

Abstract

PURPOSE:To detect rotation unbalance and prevent external outflow of lubricating oil using a simple mechanism by outputting an abnormality signal when a detection value by an acceleration sensor is a reference value or larger, and restricting or stopping supply of the lubricating oil from an oil pump. CONSTITUTION:An impact sensor (acceleration sensor) 51 is provided at an intake side housing 43 to detect rotation fluctuation of a compressor wheel 34. A detection value is inputted to an abnormality detection means 53 to be compared with a preliminarily set reference value, an abnormality signal is outputted when it is the value or more to be inputted to a solenoid valve 52, and lubricating oil flowing through a lubricating tube 45 is stopped. External outflow of the lubricating oil can thus be prevented using a simple mechanism when rotation unbalance is generated. Coping with each car type can thus be achieved, and the cost can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine having an exhaust turbocharger, and to an exhaust turbocharger oil supply apparatus for supplying, suppressing, and stopping lubricating oil to the exhaust turbocharger.

[0002]

2. Description of the Related Art FIG. 2 shows an outline of a system of an internal combustion engine having an exhaust turbocharger, and FIG. 3 shows a cross section of a conventional oil supply device for an exhaust turbocharger.

As shown in FIG. 2, an engine 10 is provided with an intake port 11 and an exhaust port 12, which can be opened and closed by an intake valve 13 and an exhaust valve 14. A piston 17 is connected to the crankshaft 15 via a connecting rod 16 and is supported in the cylinder so as to be vertically movable. A combustion chamber 18 is formed above the piston 17, and a spark plug 19 is attached to the combustion chamber 18.

The air cleaner 20 is for removing floating dust in the intake air, and is connected to the surge tank 22 and the intake port 11 of the engine 10 by an intake pipe 21. An air flow sensor 23, an intake air temperature sensor 24, and an atmospheric pressure sensor 25 are provided on the air cleaner 20 side of the intake pipe 21. On the other hand, the throttle valve 26 is provided on the surge tank 22 side of the intake pipe 21.
Also, a throttle position sensor 27 is provided. Further, a water temperature sensor 28 is provided on the engine 10 side of the intake pipe 21.

The air flow sensor 23, the intake air temperature sensor 24, the atmospheric pressure sensor 25, the throttle position sensor 26, and the water temperature sensor 28 are connected to an engine control unit (ECU) (not shown) so that the detection results can be output. ing. Also, the engine 10
An injector 29 is attached to the intake port 11 so that a predetermined amount of gasoline stored in a fuel tank (not shown) can be injected based on a command from the ECU.

An exhaust pipe is attached to the exhaust port 12 of the engine 10.
30 is connected and O ₂Sensor 31 and touch
A medium converter (three-way catalyst) 32 is mounted. That
O this₂The sensor 31 is connected to the ECU and detects it
The result can be output.

The above-mentioned internal combustion engine is equipped with an exhaust turbocharger 33 with an intercooler. That is, a compressor wheel 34 is installed in the middle of the intake pipe 21, and a turbine wheel 35 is installed in the middle of the exhaust pipe 30, and the compressor wheel 34 and the turbine wheel 35 are integrally rotatable by a rotary shaft 36.
A wastegate valve 37 is provided in the exhaust pipe 30, and a wastegate actuator 38 and a wastegate solenoid valve 39 are connected to the wastegate valve 37. The wastegate solenoid valve 39 is connected to the ECU and operates based on a command from the ECU to open and close the wastegate valve 37. Furthermore, the intake pipe 2
1, the intercooler 40 is mounted on the downstream side of the compressor wheel 34.

As shown in FIG. 2, the air sucked from the air cleaner 20 is sent to the surge tank 22 via the intake pipe 21 and then supplied to the intake port 11 of the engine 10. At this time, the throttle valve 26 controls the intake air amount. On the other hand, the ECU determines the fuel injection amount from the intake air amount detected by the air flow sensor 23 and the throttle opening detected by the throttle position sensor 27, and the injector 29 injects a predetermined amount of gasoline based on a command from the ECU. .. Therefore, a mixture of air and gasoline is supplied into the combustion chamber 18.

The air-fuel mixture is supplied from the intake port 11 into the combustion chamber 18, the piston 17 moves up and down by the drive of the crankshaft 15, the air-fuel mixture inside the combustion chamber 18 is compressed, and the spark plug 19 produces a spark. As a result, the compressed air-fuel mixture explodes and expands to operate the engine.
Then, the exhaust gas generated by the combustion of the air-fuel mixture is exhausted from the exhaust port 12 to the exhaust pipe 30, purified by the catalytic converter 32 and released to the atmosphere.

By the way, the exhaust turbocharger 33 operates at high engine speed. That is, when the rotation of the turbine wheel 35 is increased by the exhaust gas, the compressor wheel 34 rotates at high speed via the rotating shaft 36, and the intake air is compressed to 1.5 to 2.0 atmospheric pressure. Then, the intake air that has been compressed is cooled by the intercooler 40, and the intake air is sent to the combustion chamber 18. Further, when the supercharging pressure rises and becomes a predetermined value abnormal, the waste gate valve 37 is opened to directly discharge the exhaust gas without guiding it to the turbine wheel 35.

Here, the structure of the exhaust turbocharger 33 will be described in detail. As shown in FIG. 3, the rotary shaft 36, in which the compressor wheel 34 and the turbine wheel 35 are fixedly connected to each other at the shaft end, has a center housing 41 and a plurality of bearings 4.
It is rotatably supported via 2. The compressor wheel 34 is housed in the intake side housing 43 connected to the intake pipe 21, and the turbine wheel 35 is housed in the exhaust side housing 44 connected to the exhaust pipe 30.

Since the exhaust turbocharger 33 rotates at high speed, a large amount of lubricating oil is supplied to the bearing 42 that supports the rotating shaft 36. That is, the tip end of the oil supply pipe 45 whose base end is connected to an oil pan (not shown) of the engine 10 is connected to the oil jet 46 attached to the center housing 41. The oil jet 46 communicates with each bearing 42 via a plurality of oil passages 47 formed in the center housing 41. In addition, the center housing 41
A return pipe 48 having a tip connected to an oil pan is connected to the lower part of the. A seal member 49 is attached to each end of the center housing 41 in the axial direction of the rotary shaft 36.

Therefore, the lubricating oil is supplied from the oil pan to the oil supply pipe 4
5 is supplied to the oil jets 46, and is further supplied to the bearings 42 via the oil passages 47 in the center housing 41. After that, the overflowed lubricating oil is returned to the return pipe 48.
Returned to the oil pan.

[0014]

In the above-described conventional lubricating system for the exhaust turbocharger, the exhaust turbocharger 33 is generated for some reason while the engine 10 is operating.
There is a case that the supply of the lubricating oil cannot be properly controlled due to the failure of the. For example, the air cleaner 20
Foreign matter enters the intake pipe 21 during cleaning of the compressor wheel 34, which may damage the blades of the compressor wheel 34, or the compressor wheel 34, or the turbine wheel 3.
There is a crack in 5 and it may be damaged during rotation.
Then, there is a problem that the rotation of the rotary shaft 36 (the compressor wheel 34, the turbine wheel 35) becomes unbalanced and tilts, and the lubricating oil flows over the seal member 49 to the outside.

If the lubricating oil flows out to the outside in this way, the bearing 42 of the rotary shaft 36 is not sufficiently supplied with the lubricating oil and seizure occurs. When the lubricating oil flows out to the intake side, the lubricating oil flows into the combustion chamber 18 from the intake pipe 21 and abnormally burns, the pressure in the combustion chamber 18 rises, the connecting rod is deformed, and the lubricating oil When the gas flows out to the exhaust side, white smoke is generated by the exhaust pipe 30 having a high temperature.

As a solution to such a problem, the technique disclosed in JP-A-64-80720 has been proposed. This is because the abnormality detection means compares the signal output from the air pressure sensor with the standard intake pressure and outputs an abnormality signal when it exceeds a predetermined value, and the lubrication restriction means outputs the lubricating oil to the exhaust turbocharger. The supply of electricity is suppressed or stopped.

However, in the exhaust turbocharger lubrication apparatus disclosed in Japanese Patent Laid-Open No. 64-80720, an abnormality of the exhaust turbocharger is detected based on the engine operating condition and intake pressure. Therefore, there is a problem that the predetermined value differs depending on the type of engine or exhaust turbocharger, and there is no compatibility with the vehicle type. Therefore, various setting values must be set for each vehicle type, and this setting is also difficult.

Further, since the abnormality of the exhaust turbo supercharger is detected, a large number of various sensors are required, which complicates the structure and makes control difficult.

The present invention is intended to solve the above problems, and an object thereof is to provide an oil supply device for an exhaust turbocharger, which simplifies the structure and is compatible with each vehicle type. ..

[0020]

SUMMARY OF THE INVENTION In an oil supply device for an exhaust turbocharger of the present invention for achieving the above object, a compressor wheel and a turbine wheel housed in a housing are integrally rotatable by a rotating shaft. In an exhaust turbocharger in which lubricating oil discharged from an oil pump driven by an engine is connected to a bearing portion of the rotary shaft, an acceleration sensor mounted in the housing and detected by the acceleration sensor Abnormality detecting means for outputting an abnormal signal when the detected value is equal to or greater than a preset standard value, and lubricating oil from the oil pump to the bearing portion of the rotating shaft based on the abnormal signal output from the abnormality detecting means. And a refueling control means for suppressing or stopping the supply of oil.

[0021]

When the compressor wheel or turbine wheel in the exhaust turbocharger is damaged, rotational imbalance occurs. The acceleration sensor detects vibration in the housing, and the abnormality detecting means compares the detected value with a preset standard value and outputs an abnormal signal when the detected value is equal to or larger than the standard value. Then, the oil supply control means suppresses or stops the supply of the lubricating oil to the bearing portion of the rotating shaft based on the abnormality signal.

[0022]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing an oil supply device for an exhaust turbocharger according to an embodiment of the present invention. The members having the same functions as the conventional ones are designated by the same reference numerals, and the duplicated description will be omitted.

As shown in FIG. 1, the impact sensor 5 is installed in the intake side housing 43 which houses the compressor wheel 34.
1 is mounted, and the vibration in the intake side housing 43, that is, the rotation fluctuation of the compressor wheel 34 can be detected. Further, an electromagnetic valve 52 as an oil supply control means is mounted in the middle of the oil supply pipe 45 connecting the oil pan of the engine and the oil jet 46 attached to the center housing 41, and each bearing of the oil pump to the rotary shaft 36. The supply of lubricating oil to 42 can be stopped.

The abnormality detecting means 53 is connected to the impact sensor 51, and the detection value detected by the impact sensor 51 is input. The abnormality detecting means 53 has a preset standard value of vibration in the housing 43 stored therein, compares the detected value with the standard value, and outputs an abnormal signal when the detected value is equal to or larger than the standard value. .. Then, the abnormality detecting means 53 is connected to the electromagnetic valve 52, and when the abnormality signal is input to the electromagnetic valve 52, the lubricating oil flowing through the oil supply pipe 45 can be stopped.

When the exhaust turbocharger operates at high engine speed, the compressor wheel 34 (rotating shaft 36) and turbine wheel 35 also rotate at high speed. At this time, if the compressor wheel 34 or the turbine wheel 35 is damaged, an unreasonable force acts on the rotating shaft 36, and the bearing 42 cannot support the rotating shaft 36.
This damages the seal member 49 and also causes the lubricating oil to leak to the outside.

However, in the case of this embodiment, the impact sensor 51 detects a rotational imbalance (vibration) due to damage to the compressor wheel 34 or the turbine wheel 35, and outputs the detected value to the abnormality detecting means 53. The abnormality detecting means 53 compares the detected value with a preset standard value and outputs an abnormality signal to the electromagnetic valve 52 when the detected value is equal to or larger than the standard value. Then, the electromagnetic valve 52 is closed based on the abnormality signal, and the valve jet 46 from the oil supply pipe 45 is closed.
Stop the flow to. Therefore, the supply of the lubricating oil to the bearing 42 of the rotary shaft 36 is stopped, and the external leakage of the lubricating oil is prevented. The pressure in the housing of the exhaust turbocharger is 1 to 5 G in the normal state and 15 to 20 G in the abnormal state.

Although the acceleration sensor is applied as the impact sensor 51 in the above embodiment, the invention is not limited to this, and the rotation plan balance (vibration) of the rotary shaft 36 is not limited to this.
As long as it can detect Further, although the flow of the lubricating oil in the oil supply pipe 45 is stopped when the exhaust turbocharger is abnormal, the flow of the lubricating oil may be restricted in order to prevent seizure of the rotary shaft 36.

[0029]

As described above in detail with reference to the embodiments, according to the oil supply device for the exhaust turbocharger of the present invention, the rotational imbalance when the compressor wheel or the turbine wheel is damaged is generated. The acceleration sensor detects, and the abnormality detection means outputs an abnormality signal when the detected value is equal to or greater than a preset standard value, and the lubrication control means outputs lubricating oil to the bearing portion of the rotating shaft based on the abnormality signal. Since the supply of oil is suppressed or stopped, it is possible to reliably detect the rotational imbalance of the rotary shaft and prevent the outflow of lubricating oil with a simple structure, as well as the conventional structure, and to respond to each vehicle type. Therefore, the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an oil supply device for an exhaust turbocharger according to an embodiment of the present invention.

FIG. 2 is a system schematic diagram of an internal combustion engine having an exhaust turbocharger.

FIG. 3 is a cross-sectional view of a conventional oil supply device for an exhaust turbocharger.

[Explanation of symbols]

 10 engine 18 combustion chamber 21 intake pipe 30 exhaust pipe 33 exhaust turbocharger 34 compressor wheel 35 turbine wheel 36 rotary shaft 41 center housing 42 bearing 45 oil supply pipe 47 supply path 49 seal member 51 impact sensor (acceleration sensor) 52 electromagnetic valve (Abnormality detection means) 53 Refueling control means

Claims (1)

[Claims] 1. A compressor wheel and a turbine wheel housed in a housing are integrally and rotatably connected by a rotating shaft, and lubricating oil discharged from an engine-driven oil pump is supplied to a bearing portion of the rotating shaft. In the exhaust turbocharger, an acceleration sensor mounted in the housing, an abnormality detection unit that outputs an abnormality signal when a detection value detected by the acceleration sensor is equal to or greater than a preset standard value, and An exhaust turbocharger characterized by comprising an oil supply control means for suppressing or stopping the supply of lubricating oil from the oil pump to the bearing portion of the rotary shaft based on an abnormality signal output from the abnormality detection means. Refueling device.