JP2571301B2 - Engine abnormality detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an engine for receiving an ON / OFF signal from a hydraulic pressure sensor and an ON / OFF signal from a temperature sensor to determine an abnormality of the engine. The present invention relates to an abnormality detection device.

[Conventional technology]

As shown in the table of Fig. 5, the oil pressure sensor outputs an OFF signal if the lubricating oil is at an appropriate pressure when the engine is rotating, and outputs an ON signal in the event of an abnormality that drops below a certain value. There is a B-contact type in which an ON signal is output if the lubricating oil has an appropriate pressure during engine rotation, and an OFF signal is output in the event of an abnormality that drops below a certain value. The temperature sensor also outputs an OFF signal if the coolant is at an appropriate temperature when the engine is running, and outputs an ON signal if the coolant temperature is higher than the set value. Outputs an ON signal if the temperature is appropriate, and turns OFF if an error occurs that is higher than the set value.
There is a B contact type that outputs an F signal. The A contact type is mainly used in Japan, and the B contact type is mainly used overseas.

As described above, the output signals from the oil pressure sensor and the temperature sensor are completely opposite between the A contact type and the B contact type, and the criteria for determining abnormality are also opposite. In addition, an abnormality discriminating means suitable for the format must be used. That is, when the oil pressure sensor and the temperature sensor are of the A contact type, the abnormality is detected using the A contact type abnormality determining means, and when the B contact type is used, the abnormality is detected using the B contact type abnormality determining means. Must be.

[Problems to be solved by the invention]

However, the presence of two types of abnormality determination means corresponding to the A contact type and the B contact type may cause the contact type to be erroneous when assembling the abnormality detection device, and may require replacement, distribution, and management of the abnormality detection device. There is a drawback that it becomes complicated in aspects such as.

The present invention has been made in view of such a situation, and an object thereof is to provide an abnormality detection device for an engine that can be assembled without erroneous contact types and that is convenient in terms of replacement, distribution, management, and the like. Is to do.

[Means for solving the problem]

The characteristic configuration of the engine abnormality detection device according to the present invention includes:
ON from the oil pressure sensor that detects the pressure of the engine lubricating oil
Abnormality determination means for receiving an OFF signal, an ON / OFF signal from a temperature sensor for detecting the temperature of the coolant, and an output signal from rotation detection means for detecting the rotation of the engine; When the output signal from the oil pressure sensor is ON in the engine stopped state, if the output signal of each of the oil pressure sensor and the temperature sensor is OFF in the engine rotation state, it is determined that the normal state, and, If at least one of the output signals is ON, the A-contact mode for determining an abnormal state is selected, and the output signal from the oil pressure sensor is output when the engine is stopped.
When the output signal is OFF, the output signal of the oil pressure sensor and the temperature sensor is ON in the engine rotation state, it is determined that the output signal is normal, and if at least one of the output signals is OFF, it is an abnormal state. Is configured to select the B contact mode for determining that

(Operation)

First, the abnormality determination means includes an ON / OFF signal from a hydraulic sensor that detects the pressure of the lubricating oil of 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. The output signals from the means are received, and the contact type between the oil pressure sensor and the temperature sensor is determined from these output signals. In other words, since the pressure of the lubricating oil is low when the engine is stopped, if the output signal from the oil pressure sensor is ON, it is regarded as the A contact type and the A contact mode is selected, and the output signal from the oil pressure sensor is OFF. If so, the B-contact mode is selected by regarding the B-contact mode.

Next, the abnormality determination means determines whether the engine is in a normal state or an abnormal state in a rotational state. In other words, when the A-contact mode is selected, it is determined that each of the output signals of the oil pressure sensor and the temperature sensor is OFF in the engine rotation state, and that at least one of the output signals is ON. It is determined that the state is abnormal. When the B-contact mode is selected, if the output signals of the oil pressure sensor and the temperature sensor are ON in the engine rotation state, it is determined that the state is normal, and if at least one of the output signals is OFF, the state is abnormal. Judge.

Here, the reason why the ON / OFF signal of the oil pressure sensor is used for selecting the contact mode is that when the engine is stopped, the content of the ON / OFF signal of the oil pressure sensor does not change in either a normal state or an abnormal state. For the temperature sensor
This is because the content of the OFF signal may change between a normal state and an abnormal state. For example, in the case of the A contact type, when the temperature of the coolant rises in an engine rotation state and becomes abnormal, and the temperature sensor outputs an ON signal, when the engine is stopped, the oil pressure sensor reliably outputs an ON signal,
The temperature sensor continues to output an ON signal until the temperature of the coolant drops even after the engine is stopped, and outputs an OFF signal after a certain time has elapsed.

〔The invention's effect〕

Since it is suitable for any type of contact type oil pressure sensor and temperature sensor, it is possible to assemble the contact type without error. It is also convenient in terms of production, distribution, management and exchange.

〔Example〕

Hereinafter, an embodiment in which the present invention is applied to a diesel engine will be described with reference to the drawings.

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

With such a configuration, the engine oil is cooled by the oil pan (1), and then is drawn up by the oil pump (3) while being filtered through the first oil filter (2). After being released by the oil pump (3), further small dust is filtered by the second oil filter (6) and passes through an oil passage (9) in the crankcase (8) (see FIG. 4). , Crankshaft (10), connecting rod (1
1), forcibly sent to the idle gear (12), camshaft (13), rocker arm shaft (14), etc., to lubricate their moving parts.

The other parts are lubricated by splashing with the crankshaft (10) or falling of oil leaking from the gaps between the parts.

The oil pressure sensor (7) is provided for detecting a decrease in oil pressure in the lubrication system from the cam bearing (16).
It is communicated to the control device (H) as shown in the figure. However, here, the A-contact type is adopted, and when the engine is running in a normal state, the OFF signal is output, but when the decrease of the oil pressure exceeding the set value is detected, the ON signal is output. It shall be.

As shown in FIG. 4, the cooling system of the diesel engine includes a water pump (17), a fan (18), a radiator (19), a thermostat (20), and a temperature sensor (2).
1) Consists of a return pipe (22).

With such a configuration, after the coolant is forcibly fed into the crankcase (8) and the cylinder head (23) by the water pump (17), a part of the coolant is directly returned to the water pump (17) and again. The remainder circulates through the thermostat (20) to the radiator (19) where it is cooled.

The thermostat (20) is of a wax pellet type, and is in a closed state when the temperature is low, but is configured so that the enclosed wax expands and opens when the temperature is high.

The temperature sensor (21) is provided for detecting the temperature of the coolant sent to the cylinder head (23), and is provided with a control device (H) (corresponding to an abnormality determination unit).
Has been contacted. However, here, the A-contact type is adopted, and when the engine is running in a normal state, the OFF signal is output, but when the temperature exceeding the set value is detected, the ON signal is output. I do.

The oil pump (3) and the 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) (corresponding to rotation detection means) for detecting whether the engine is rotating, an alarm device (25) for issuing an abnormality alarm, and a mode display for displaying a mode. The device (26) is connected together with the hydraulic pressure sensor (7) and the temperature sensor (21). Rotation sensor (2
4) Detects the rotation of the camshaft (13) and outputs an ON signal if the rotation speed is equal to or higher than the set rotation speed, and outputs an OFF signal if the rotation speed is lower than the set rotation speed. .

The control device (H) receives ON / OFF signals output from the oil pressure sensor (7), the temperature sensor (21), and the rotation sensor (24), and the oil pressure sensor (7) and the temperature sensor (21) After determining which of the contact types, the A contact and the B contact, corresponds to, it is further determined whether or not the engine rotation state is normal.

Next, the operation of the control device (H) will be described with reference to the flowchart of FIG. This operation is repeated until the power is turned off. Step numbers in the figure are denoted by #.

First, when the power is turned on, the ON / OFF signal of the rotation sensor (24) is detected. If the OFF signal is output, it is determined that the engine is in a stopped state and the oil pressure sensor (7) is turned ON / OFF.
A signal is detected (steps 1 and 2). Oil pressure sensor (7) is O
In the case of N, the A contact mode is set and the mode display device (2
6), and if OFF, the B contact mode is set and displayed on the mode display device (26) (steps 3 and 4).

When the ON signal is output from the rotation sensor (24), the set mode is determined (steps 1, 10). When the A-contact mode is set, if the OFF signal is output from both the oil pressure sensor (7) and the temperature sensor (21), the process returns to step 1 and at least one of the output signals is ON. If so, it is determined to be in an abnormal state, the alarm device (25) is activated, and the process returns to step 1 (step 5,
6,7). When the B contact mode is set,
If ON is output from both the oil pressure sensor (7) and the temperature sensor (21), the process returns to step 1, and if at least one of the output signals is OFF, it is determined that an abnormal state has occurred and the alarm device (25) ), And then return to step 1 (steps 8, 9, 7).

In this embodiment, the control device (H) determines normal or abnormal from the ON / OFF signals of the A-contact type hydraulic sensor (7) and the temperature sensor (21). As can be seen, it is compatible with the B-contact type oil pressure sensor (7) and temperature sensor (21).
Normal and abnormal can also be determined from the F signal. B
In the case of the contact type, the B contact mode is set in step 4.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the structure shown in the attached drawings.

[Brief description of the drawings]

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

Claims (1)

(57) [Claims] An ON / OFF signal from a hydraulic pressure sensor for detecting a pressure of lubricating oil of an engine, an ON / OFF signal from a temperature sensor for detecting a temperature of a coolant, and rotation of the engine. Abnormality detecting means (H) for receiving an output signal from a rotation detecting means (24) for detecting the output signal from the hydraulic pressure sensor (7) when the engine is stopped. Is ON
If the output signals of the oil pressure sensor (7) and the temperature sensor (21) are OFF in the engine rotation state, it is determined that the state is normal, and if at least one of the output signals is ON, the state is abnormal. When the A-contact mode to be determined is selected and the output signal from the oil pressure sensor (7) is OFF while the engine is stopped, the oil pressure sensor (7) and the temperature sensor (21) are turned on when the engine is rotating. An abnormality detection of an engine configured to select a B-contact mode in which the output signal is determined to be normal if the output signal is ON, and is determined to be abnormal if at least one of the output signals is OFF. apparatus.