JPH0450434A - Abnormality detector of engine - Google Patents

Abstract

PURPOSE:To carry out assembly work without any mistake on selection of contact mode by judging presence of a normal condition when output signals of a an oil pressure sensor and a temperature sensor are set ON in an engine rotating condition, and judging presence of an abnormal condition when it is set OFF, in the case when the output signal form the oil pressure sensor is set OFF in an engine stop condition. CONSTITUTION:An abnormal condition judging means H, judges whether a normal condition or an abnormal condition is present when an engine is in rotating condition. Namely in the case when an A contact point mode is selected, it output signals of an oil pressure sensor 7 and a temperature sensor 21 are set OFF in the engine rotating condition, pressure of the normal condition is determined and if it is set ON, it presence of the abnormal condition is determined. In the case, when a B contact point mode is selected, it the output signals of the oil pressure sensor 7 and the temperature sensor 21 are set ON in the engine rotating condition, the pressure of normal condition, is determined and if it is set OFF, presence of the abnormal condition is determined.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is an engine control system for determining engine abnormality by receiving ON/OFF signals from a hydraulic pressure sensor and ON/OFF signals from a temperature sensor. The present invention relates to an abnormality detection device.

[Conventional technology]

As shown in the table in Figure 5, the oil pressure sensor has an A contact type that outputs an OFF signal if the lubricating oil pressure is at an appropriate level when the engine is rotating, and outputs an ON signal if the pressure drops beyond a certain value. There is also a B contact type that outputs an ON signal if the lubricating oil has an appropriate pressure when the engine is rotating, and outputs an OFF signal when the pressure drops to a certain value or more. In addition, the temperature sensor also has an A contact type that outputs an OFF signal when the coolant is at an appropriate temperature when the engine is rotating, and outputs an ON signal when the temperature is higher than the set value (when the temperature becomes abnormal). There is a B contact type that outputs an ON signal when the temperature of the liquid is appropriate, and outputs an OFF signal when the temperature exceeds the set value.The A contact type is mainly used in Japan; Contact type types are mainly used overseas.

In this way, the output signals from the oil pressure sensor and temperature sensor are completely opposite between the A contact type and the B contact type, and the criteria for determining an abnormality are also completely opposite, so check the contact types of the oil pressure sensor and temperature sensor. The abnormality determination means must be used in accordance with the format. In other words, if the oil pressure sensor and temperature sensor are A contact type, the abnormality determination means for A contact type is used to detect the abnormality, and if they are B contact type, the abnormality determination means for B contact type is used to detect the abnormality. must be done.

[Problem to be solved by the invention]

However, the existence of two types of abnormality determination means depending on the A contact type and B contact type means that there is a risk of incorrect contact type when assembling the abnormality detection device, and there is a risk of replacing, distributing, and managing the abnormality detection device. There is a problem that it becomes complicated in other aspects as well.

The present invention has been made with attention to such circumstances,
The purpose is to provide an engine abnormality detection device that can be assembled without making a mistake in the contact type and is convenient in terms of replacement, distribution, management, etc.

[Means to solve the problem]

The characteristic configuration of the engine abnormality detection device according to the present invention is that the ON signal from the oil pressure sensor that detects the pressure of lubricating oil in the engine is
- Abnormality determination means is provided for receiving the OFF signal, the ON/○FF signal from the temperature sensor that detects the temperature of the coolant, and the output signal from the rotation detection means that detects the rotation of the engine, and the abnormality determination means is provided. The means determines that if the output signal from the oil pressure sensor is ON when the engine is stopped, and the output signal of each of the oil pressure sensor and the temperature sensor is OFF when the engine is rotating, it is a normal state; In addition, when the A contact mode is determined to be an abnormal state if it is ON, and if the output signal from the oil pressure sensor is OFF when the engine is stopped, the output signal from the oil pressure sensor and the temperature sensor is changed when the engine is running. The present invention is configured to select a B contact mode in which it is determined that the output signal is in a normal state if it is ON, and that it is determined to be in an abnormal state if the output signal is OFF.

[For production]

First, the abnormality determination means uses an ON/OFF signal from a hydraulic sensor that detects the pressure of lubricating oil in the engine, an ON/OFF signal from a temperature sensor that detects the temperature of the coolant, and a rotation detection that detects the rotation of the engine. and determines the type of contact between the oil pressure sensor and the temperature sensor from these output signals. In other words, when the engine is stopped, the lubricating oil pressure is low, so if the output signal from the oil pressure sensor is ON, it is assumed to be an A contact type and the A contact mode is selected, and the output signal from the oil pressure sensor is OFF. If there is, it is assumed to be a B contact type and the B contact mode is selected.

Next, the abnormality determining means determines whether the engine is in a normal state or an abnormal state in its rotating state.

In other words, when the A contact mode is selected, if the output signals of the oil pressure sensor and temperature sensor are OFF while the engine is rotating, it is determined to be a normal state, and if they are ON, it is determined to be an abnormal state. . When the B contact mode is selected, if the output signals of the oil pressure sensor and temperature sensor are ON in the engine rotation state, it is determined to be a normal state, and if they are OFF, it is determined to be an abnormal state.

Here, the ON/OFF signal of the oil pressure sensor is used to select the contact mode because when the engine is stopped, the content of the ON/OFF signal of the oil pressure sensor does not change in either normal or abnormal conditions. On the other hand, the ON/OFF signal of the temperature sensor may change in content between a normal state and an abnormal state. For example, in the A contact type, if the temperature of the coolant rises while the engine is rotating and an abnormal state occurs, and the temperature sensor outputs an ON signal,
The oil pressure sensor reliably outputs an ON signal when the engine is stopped, but the temperature sensor continues to output an ON signal even after the engine is stopped until the coolant temperature drops, and then outputs an OFF signal after a certain amount of time. It outputs.

〔Effect of the invention〕

Since it is compatible with any contact type of oil pressure sensor and temperature sensor, it is possible to assemble the contact type without making a mistake. It also becomes convenient in terms of production, distribution, management, exchange, etc.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a diesel engine will be described below with reference to the drawings.

As shown in Figure 3, the circulation system of a diesel engine includes an oil pan (1), a first oil filter (2),
It is composed of an oil pump (3), a safety valve (4), a relief valve (5), a second oil filter (6), and an oil pressure sensor (7).

With this configuration, engine oil is cooled in the oil pan (1) and then filtered through the first oil filter (2) while being sucked up into the oil pump (3). After being discharged by the oil pump (3), even smaller dust is filtered by the second oil filter (4), and the oil passage (9) in the crankcase (8) (see Figure 4) is filtered out.
Through the crankshaft (10), connecting rod (11),
It is forcibly sent to the idle gear (12), camshaft (13), rocker arm shaft (14), etc., and lubricates those moving parts.

In addition, other parts are lubricated by splashing from the crankshaft (10) or by falling oil leaking from the gaps between the parts.

The oil pressure sensor (7) is provided to detect a drop in oil pressure in the lubrication system from the cam bearing (16), and is the first oil pressure sensor (7).
As shown in the figure, it is connected to a control device (H). However, the A contact type is used here, and when the engine is rotating normally, it outputs an OFF signal, but when it detects a drop in oil pressure above the set value, it outputs an ON signal.
It shall output a signal.

As shown in Figure 4, the diesel engine cooling system consists of a water pump (17), a fan (18), a radiator (19), a thermostat (20), a temperature sensor (21), and a return pipe (22). ing.

With this configuration, the coolant is supplied to the water pump (1
After being forcibly sent to the crankcase (8) and cylinder head (23) at step 7), part of the water is returned directly to the water pump (17) and circulated again, but the rest passes through the thermostat (20). It is sent to a radiator (19) and cooled.

The thermostat (20) is of a wax pellet type, and is configured so that the valve is closed when the temperature is low, but the sealed wax expands and the valve is opened when the temperature is high.

The temperature sensor (21) is provided to detect the temperature of the coolant sent to the cylinder head (23), and is connected to the control device (H) (corresponding to abnormality determining means). There is. However, an A contact type is used here, which outputs an OFF signal when the engine is rotating under normal conditions, but outputs an ON signal when a temperature higher than the set value is detected. do.

In addition, the oil pump (3) and water pump (17)
is driven by power from the engine. In other words, it is linked to the rotation and stop of the engine.

The control device (H) includes a rotation sensor (24) that detects whether or not the engine is rotating (corresponding to rotation detection means), an alarm device (25) that issues an abnormality alarm, and a mode display that displays the mode. The device (26) includes an oil pressure sensor (7
) and a temperature sensor (21). The rotation sensor (24) detects the rotation of the camshaft (13) and outputs an ON signal if the rotation is above a set rotation speed,
If the rotation speed is lower than the set rotation speed, an OFF signal is output.

The control device (H) controls the ON/O output from the oil pressure sensor (7), temperature sensor (21), and rotation sensor (24).
After receiving the FF signal, the oil pressure sensor (7) and temperature sensor (
After determining which contact type, A contact or B contact, 21) corresponds to, it is further determined whether or not the engine rotational state is normal.

Next, the operation of the control device (H) will be explained using the flowchart shown in FIG. Note that this operation is repeatedly executed until the power is turned off.

Step numbers in the diagram are indicated with # attached.

First, when you turn on the power, the rotation sensor (24) turns on and off.
An FF signal is detected, and if an OFF signal is output, it is assumed that the engine is stopped and an ON/OFF signal of the oil pressure sensor (7) is detected (steps 1 and 2). When the oil pressure sensor (7) is ON, the A contact mode is set and displayed on the mode display device (26), and when it is OFF, the B contact mode is set and displayed on the mode display device (26). Steps 3 and 4).

If the rotation sensor (24) outputs an ON signal, determine the set mode (step 1.10).
). If the A contact mode is set, both the oil pressure sensor (7) and temperature sensor (21) are turned OFF.
If a signal is output, the process returns to step 1, and if an ON signal is output from any of them, the alarm device (25) is activated and then the process returns to step 1 (step 5.6.7).

In addition, when the B contact mode is set, if ON is output from both the oil pressure sensor (7) and temperature sensor (21), the process returns to step 1, and if an OFF signal is output from either of them, the process returns to step 1. After activating the alarm device (25), return to step 1 (step 8.9.7).

In this embodiment, the control device (H) controls ON/OFF of an A contact type oil pressure sensor (7) and a temperature sensor (21).
Normality and abnormality are determined from the signal, but as you can see from the flowchart above, it is also compatible with the B contact type oil pressure sensor (7) and temperature sensor (21), and these ON
・It is possible to distinguish between normal and abnormal from the OFF signal. In the case of the B contact type, the B contact mode is set in step 4.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the engine abnormality detection device according to the present invention, FIG. 1 is a block diagram showing the functional configuration, FIG. 2 is a flowchart of control operation, and FIG. 3 is a diagram showing a circulation system of a diesel engine. FIG. 4 is a diagram showing a cooling system for a diesel engine, and FIG. 5 is a table showing ON/OFF signals of oil pressure sensors and temperature sensors according to each contact type. (7)... Oil pressure sensor, (21)...
Temperature sensor, (24)...Rotation detection means, (H
)...Means for determining abnormality.

Claims (1)

[Claims] ON/OFF signals from the oil pressure sensor (7) that detects the pressure of lubricating oil in the engine, ON/OFF signals from the temperature sensor (21) that detects the temperature of the coolant, and rotation detection that detects the rotation of the engine. Abnormality determining means (H) receiving the output signal from the means (24) is provided, and the determining means (H) determines when the output signal from the oil pressure sensor (7) is ON when the engine is stopped. In the engine rotation state, if the respective output signals of the oil pressure sensor (7) and the temperature sensor (21) are OFF, it is determined to be a normal state, and if they are ON, it is determined to be an abnormal state. is selected, and the output signal from the oil pressure sensor (7) is OFF when the engine is stopped/state.
In this case, the output signals of the oil pressure sensor (7) and the temperature sensor (21) are O when the engine is rotating.
An abnormality detection device for an engine configured to select a B contact mode in which a normal state is determined if N is determined, and an abnormal state is determined if OFF.