JP3053305B2 - Failure prediction device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting a pressure, a flow rate, a temperature, and the like of a fluid flowing in each part of an engine to predict a failure.

[0002]

2. Description of the Related Art In order to always operate an internal combustion engine in a good state, appropriate maintenance and inspection are necessary. Particularly, if a failure can be predicted and necessary measures can be taken in advance, an emergency stop or engine damage during operation is required. It is effective to prevent such serious failures and accidents as before. For this reason, for example, attempts have been made to detect a precursor of a specific failure from abnormal vibration, sound, temperature, etc., and much research has been conducted on the precursor, but even if an abnormality occurs, emergency stop immediately For light failures that do not lead to engine damage, the development of predictive technology has been delayed because it is not so important. However, even a minor failure can cause serious failures and accidents if left unchecked, so in reality it is necessary to take immediate action.

[0003]

The present invention pays attention to such a problem, and in particular, detects a sign of various kinds of failures which are regarded as minor failures before the occurrence thereof, thereby preventing the occurrence of the failures. The task was to develop such a practical prediction technology.

[0004]

In order to achieve the above object, according to the present invention, there are provided a plurality of sensors for detecting the pressure, flow rate and temperature of a fluid flowing through each part in an engine, and a plurality of sensors for detecting these pressures. The change in the detected value is compared with a standard change tendency set in advance according to various abnormalities, and if the change in the detected value indicates a tendency that matches the combination of the specific change tendency, the abnormality at the portion corresponding to the change tendency is determined. Determining means for determining, and output means for outputting a determination result by the determining means;
And In particular, the present invention is directed to:
It is configured to detect an abnormality in the flow path of fuel, air supply, lubricating oil, cooling water, or the like flowing through each part in the engine, and to detect an abnormal part based on a change tendency of detection values of various sensors.

[0005]

The inventors of the present application predict that when an abnormality occurs in the fluid system as described above, the tendency of the pressure, flow rate and temperature of each system to be affected by the failure. Research was conducted by attaching a sensor to the part to be tested, and the change tendency of the sensor output that can be used as a precursor of failure was confirmed for each failure. Therefore, by comparing the standard change tendency of the detection values corresponding to various abnormalities with the change tendency of the detection values of various sensors that are actually detected in advance according to these results, the precursory phenomenon of the failure can be reduced. It can be detected accurately.

[0006]

Next, an embodiment shown in the drawings will be described. FIG. 1 is a block diagram of an apparatus according to an embodiment, wherein 1 is an internal combustion engine, 2 is a pressure sensor group, 3 is a flow sensor group, and 4 is a temperature sensor group. Each sensor 2a of the pressure sensor group 2 includes an inlet and an outlet of a filter provided downstream of a fuel pump in a fuel system in the engine 1, a turbocharger outlet, a pump outlet of a cooling water and an engine outlet,
It is attached to each required location such as lubricating oil system. Each flow sensor 3a of the flow sensor group 3 is
For example, they are attached to a fuel system, for example, upstream of a fuel pump and a fuel return flow path to a fuel tank. The sensors 4a of the temperature sensor group 4 are attached to, for example, an air supply pipe, an exhaust pipe, a supercharger inlet, an engine inlet and an outlet of primary cooling water, various parts of a secondary cooling water passage, various parts of a lubricating oil system, and the like. I have.

Reference numeral 5 denotes a channel selector, 6 denotes an effective value calculator, 7 denotes a comparator, 8 denotes an output device, and 9 denotes a controller for controlling these. Generally, a computer can be used as the controller 9. In addition,
Although not shown in the following embodiments because they are not directly used, a rotation sensor, a vibration sensor, and the like are appropriately provided in necessary places, respectively, and a viscosity sensor of the lubricating oil is also provided in the lubricating oil system to detect other failures. And used for control.

The specific operation for each fault will be described later. First, the operation of the apparatus shown in FIG. 1 will be outlined. After the output of each sensor is selected by the channel selector 5 and converted into an effective value by the effective value calculator 6, the signal level is compared by the comparator 7 with a reference value set in advance according to various abnormalities. The result is output from the output device 8 as a prediction signal S, and an alarm device or a notification device (not shown) is operated to notify the abnormality. As the output device 8, a printer or CRT
A display or the like can also be used. FIG. 2 is a flowchart showing a basic procedure of the above operation.

The clogging of the flow meter strainer and the filter which is likely to occur in the fuel system is described below. Next, the operation according to the first aspect of the present invention for detecting such abnormalities will be described.
FIG. 3 is a system diagram of a fuel system.
Is an integrating flow meter, 13 is a fuel feed pump, 14 is a filter, and 15 is an injection pump. Here, pressure gauges 2a-1 and 2a-2 as pressure sensors are disposed at the inlet and the outlet of the filter 14, respectively, and a flow meter 3a as a flow sensor.
-1 and 3a-2 are the fuel return flow path 16 upstream of the fuel feed pump 13 and between the injection pump 15 and the fuel tank 11.
The output of each sensor is input to a comparator 7 via an effective value calculator 6 and the change is monitored.

According to research, when clogging occurs upstream or downstream of the fuel feed pump 13, both the amount of fuel supplied by the fuel feed pump 13 and the amount of fuel returned to the fuel tank 11 decrease, and In the case of clogging upstream, both the pressure at the inlet and the outlet of the filter 14 decrease, whereas in the case of clogging downstream, especially in the filter 14, the pressure at the inlet of the filter 14 increases and the pressure at the outlet of the filter 14 increases. The pressure was found to drop. Therefore, when the detected values of the flow meters 3a-1 and 3a-2 both tend to decrease and the detected values of the pressure gauges 2a-1 and 2a-2 both tend to decrease, the upstream of the fuel feed pump 13 Can be determined to be clogged, in this case, the flow meter 3a-1
Of the strainer 3b-1 is expected. If the detection value of the pressure gauge 2a-1 tends to increase and the detection value of the pressure gauge 2a-2 tends to decrease, it can be determined that clogging has occurred downstream of the fuel feed pump 13 and the filter 14 Clogging is expected.

Note that, even when the fuel feed pump 13 is poorly pumped due to, for example, a broken spring, the detected value of each sensor shows the same tendency as that of clogging upstream of the fuel feed pump 13. Since the fuel return amount and the pressure at the outlet of the filter 14 become almost zero,
It was possible to detect it clearly distinguished from upstream clogging. Also, check valve 15 of injection pump 15
In the case of the failure a, the pressures at the inlet and the outlet of the filter 14 both decrease, but since the supply amount and return amount of the fuel, particularly the return amount, increase, this can also be clearly distinguished and detected.

Next, detection of clogging in the air supply filter according to the second aspect of the present invention will be described. According to research,
In this case, the fuel consumption is deteriorated, so that the fuel tank 11
Feed to the fuel feed pump 1
It has been found that the difference from the fuel supply amount by No. 3, that is, the net fuel flow increases, the pressure at the turbocharger outlet decreases, and the exhaust gas temperature further increases. Therefore, the flow meter 3 shown in FIG.
The detected value of a-1 tends to decrease and the flow meter 3a-2
And the detected value of the pressure sensor 2a disposed at the outlet of the supercharger (not shown) tends to decrease, and is provided at the exhaust pipe of each cylinder and at the inlet of the supercharger. If the detected values of the temperature sensors 4a are all increasing, it can be determined that the air supply filter is clogged.

Next, an abnormality detection of the cooling water system according to the third aspect of the present invention will be described. FIG. 4 is a system diagram of the cooling water system of this embodiment, and shows a case of an engine using secondary cooling water. 21 is an intercooler, 22 is a fresh water cooler, 23 is a lubricating oil cooler, 24 is a secondary cooling water source, 25
Is a secondary cooling water pump, and 26 is a secondary cooling water outlet. 2
The secondary cooling water is sent to the engine 1 by the pump 25, the air is supplied by the intercooler 21, the primary cooling water is supplied by the fresh water cooler 22,
The lubricating oil is cooled by the lubricating oil cooler 23 and
From the engine, and as the secondary cooling water, for example, seawater is used. Here, the pressure gauges 2a-3 and 2a-4 are connected to the outlet of the secondary cooling water pump 25 and
A secondary cooling water outlet 26, that is, an inlet and an outlet of the engine 1, respectively, and temperature sensors 4a-1 and 4a-2 are provided at the primary cooling water outlet of the fresh water cooler 22 and the lubricating oil outlet of the lubricating oil cooler 23, respectively. Arranged, and a temperature sensor 4a-
3, 4a-4 and 4a-5 are intercoolers 2 respectively.
1, disposed on the outlet side of the fresh water cooler 22 and the lubricating oil cooler 23.

According to research, when air enters the cooling water or clogging occurs at the inlet side of the cooling water pump, the temperatures of the cooling water and the lubricating oil rise and the outlet side of the cooling water pump. If the pressure of the cooling water drops and clogging occurs at the engine outlet side, it is found that the temperature of the cooling water and the lubricating oil respectively increase as above, but the pressure of the cooling water at the engine outlet side increases. Have been. Therefore, in the configuration of FIG. 4, when the detection values of the temperature sensors 4a-1 to 4a-5 tend to increase, it can be determined that an abnormality has occurred in the cooling water system, and the abnormality indicates that the detection value of the pressure gauge 2a-3 has decreased. If there is a tendency, mixing of air into the secondary cooling water or secondary cooling water pump 2
5 is considered to be clogged on the inlet side, and the pressure gauge 2a-3
No change is seen in the detected value of. If the detected value of the pressure gauge 2a-4 tends to increase, it is considered that the clogging is at the secondary cooling water outlet 26 side. In addition, at the time of these abnormalities, the temperature of the cooling water after cooling each cylinder also rises, so that this temperature rise can also be added as information for determination.

From the intercooler 21 to the lubricating oil cooler 23
When the clogging occurs in the path of the secondary cooling water up to the above, the temperature and pressure detected by each sensor change in a different tendency from the above-described abnormality as follows. That is, when the intercooler 21 is clogged, the exhaust gas temperature and the supply air temperature at the outlet of the intercooler 21 increase, and the temperature difference between the secondary cooling water before and after the intercooler 21 decreases. Shimizu cooler 2
2, the temperature difference between the supply air before and after the intercooler 21 and the temperature difference between the lubricating oil before and after the lubricating oil cooler 23 do not change so much, and the pressure on the outlet side of the secondary cooling water pump 25 increases. Rises, the pressure on the secondary cooling water outlet 26 side decreases,
The temperature of the primary cooling water slightly increases. Lubricating oil cooler 2
In the clogging in 3, the temperature of the lubricating oil increases and the temperature difference of the lubricating oil before and after the lubricating oil cooler 23 decreases, the pressure at the outlet side of the secondary cooling water pump 25 increases, and the secondary cooling water The pressure on the outlet 26 side decreases.

Further, when the capacity of the secondary cooling water pump 25 is reduced due to a partial breakage of the impeller or the like, the pressure on the outlet side of the pump 25 is reduced and the flow rate of the secondary cooling water is reduced. The temperature of the secondary cooling water at each outlet side of the fresh water cooler 22 and the lubricating oil cooler 23 rises.
If the secondary cooling water pump 25 is stopped, the impeller is totally damaged, or the secondary cooling water path is completely blocked, etc.
As the temperature of the secondary cooling water rises, the temperature of the air supply, primary cooling water, lubricating oil, exhaust, etc. rises. Therefore, these abnormalities can be distinguished and detected by monitoring the changes in the temperature and the pressure by appropriately using sensors not shown in FIG.

[0017]

As is apparent from the above description, the present invention provides a plurality of sensors for detecting the pressure, flow rate, and temperature of the fluid flowing through each part of the engine, and changes in the detected values of these sensors. Is matched with a change tendency indicating an abnormality at a specific location, it is determined that the location is abnormal. Therefore, various failures that are considered to be minor failures that can cause serious failures and accidents if left unattended are predicted in advance, and necessary measures are taken in advance to prevent serious failures such as emergency stop or engine damage during operation. It is possible to prevent a serious failure or accident from occurring, and to easily operate the engine in a good condition at all times.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a flowchart showing a basic procedure of the operation of the embodiment.

FIG. 3 is a system diagram of a fuel system of the embodiment.

FIG. 4 is a system diagram of a cooling water system of the embodiment.

[Explanation of symbols]

 Reference Signs List 1 internal combustion engine 2 pressure sensor group 2a, 2a-1 to 2a-4 pressure sensor (pressure gauge) 3 flow sensor group 3a, 3a-1, 3a-2 flow sensor (flow meter) 4 temperature sensor group 4a, 4a-1 -4a-5 Temperature sensor 5 Channel selector 6 Effective value calculator 7 Comparator 8 Output device 9 Controller 11 Fuel tank 13 Fuel feed pump 14 Filter 16 Fuel return flow path 25 Secondary cooling water pump 26 Secondary cooling water outlet

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F02B 77/08 G01D 21/00 G05B 23/02

Claims (3)

(57) [Claims] 1. A plurality of sensors for detecting pressure, flow rate and temperature of a fluid flowing through each part in an engine, and a change in the detection value of each of these sensors is standardized in advance according to various abnormalities. Determining means for comparing with a specific change tendency, and determining a failure in a portion corresponding to the change tendency when indicating a tendency corresponding to a combination of specific change trends, and output means for outputting a determination result by the determination means Wherein the plurality of sensors include at least a flow sensor and a pressure sensor provided in a fuel system, and a fuel return flow path upstream of a fuel feed pump and a fuel tank. When the detected values of the respective flow rate sensors arranged in each of the above tend to decrease, the pressure sensors arranged in the filter inlet and the outlet downstream of the fuel feed pump respectively. If the detected values are all decreasing, it is determined that clogging has occurred upstream of the fuel feed pump. A failure predicting device for an internal combustion engine, characterized in that it is configured to determine that clogging has occurred in a filter if a detection value of a sensor tends to decrease. 2. A plurality of sensors for detecting the pressure, flow rate, and temperature of a fluid flowing through each part in the engine, and changes in the detection values of these sensors are standardized in advance according to various abnormalities. Determining means for comparing with a specific change tendency, and determining a failure in a portion corresponding to the change tendency when indicating a tendency corresponding to a combination of specific change trends, and output means for outputting a determination result by the determination means A failure prediction device for an internal combustion engine, comprising: a flow sensor provided at least in a fuel system, a pressure sensor provided at a turbocharger outlet, and a temperature sensor provided in an exhaust system of the plurality of sensors. And the difference between the detection value of the flow sensor disposed upstream of the fuel feed pump and the detection value of the flow sensor disposed in the fuel return flow path to the fuel tank tends to increase. When the detection value of the pressure sensor at the turbocharger outlet tends to decrease and the detection value of the exhaust temperature sensor tends to increase, it is determined that clogging has occurred in the air supply filter. A failure prediction device for an internal combustion engine, characterized in that: 3. A plurality of sensors for detecting the pressure, flow rate, and temperature of a fluid flowing through each part in the engine, and changes in the detection values of these sensors are standardized in advance according to various abnormalities. Determining means for comparing with a specific change tendency, and determining a failure in a portion corresponding to the change tendency when indicating a tendency corresponding to a combination of specific change trends, and output means for outputting a determination result by the determination means Wherein the plurality of sensors include at least a temperature sensor and a pressure sensor provided in a cooling water system and a temperature sensor provided in a lubricating oil system, wherein the plurality of sensors include a cooling water and a lubrication oil. If the detection value of the pressure sensor provided at the outlet of the cooling water pump tends to decrease while the detection value of each oil temperature sensor is increasing, the air may be mixed in the cooling water. Is determined to be clogged on the inlet side of the engine, and if the detection value of the pressure sensor provided at the engine outlet of the cooling water is increasing, it is determined that clogging is occurring on the engine outlet side A failure prediction device for an internal combustion engine, characterized in that: