JPS6211313Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stopping device for a turbocharged engine.

Conventionally, in diesel engines equipped with a turbocharger, if the engine is stopped immediately after high-load or high-speed operation, the bearings of the turbocharger may be damaged because the engine oil temperature and exhaust temperature have not yet fallen. It could cause damage. Such turbocharged engines require engine oil temperature to be below 90°C and exhaust temperature to be approximately 200°C.
It is desirable to stop the engine after lowering the engine.

Normally, drivers do not slowly cool down the engine and then stop the engine, so in diesel engines equipped with a turbocharger, the bearings of the turbocharger are easily damaged. Therefore, the present invention has been developed in a diesel engine with a turbocharger, so even if the key switch is turned off immediately after high-load/high-speed operation, the engine will not stop unless the engine oil temperature and exhaust temperature drop below a certain temperature. The purpose of this invention is to provide a device that can automatically stop the engine.

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

FIG. 1 shows an embodiment of the present invention, in which a starting/stopping circuit for a diesel engine is shown, and a relay circuit for an automatic stopping device is shown in the drawing.

In the start/stop circuit, a battery B, a key switch 2, and a starter 3 are connected in series to form a closed circuit, and an engine stop device 4 is connected in parallel with the starter 3.

The relay circuit 2 includes a safety switch 1 connected in series between the first terminal 5 and the second terminal 7 of the key switch 2.
2 and a contact 21 of a relay 13.

A contact 21 of the relay 13 is a normally open contact, and a relay coil 22 that opens and closes this contact 21 is connected in series to a first bimetal switch 23, a second bimetal switch 24, and a battery 25 to form a relay operating circuit. are doing. The first bimetal switch 23 is configured to open and close by sensing the temperature of engine oil, and the second bimetal switch 24 is configured to open and close by sensing the exhaust temperature of the engine.

Next, the operation will be explained.

When the engine is running and the oil temperature is high,
When the bimetal switch 23 is closed and the exhaust gas temperature is high and the second bimetal switch 24 is closed, the relay 13 is also closed. (Situation shown in FIG. 1) Therefore, even if the key switch 2 is opened as shown in FIG. 1, the engine will not stop because the bypass circuit including the relay 13 is energized.

When the oil temperature or exhaust temperature drops and either the first or second bimetal switch 23 or 24 becomes open, the relay 13 becomes open and the relay circuit becomes open, so the engine stop device is activated. It turns off and the engine stops. Of course key switch 2
If the first or second bimetal switch 23, 24 is open when the key switch 2 is opened, the engine will stop at the same time as the key switch 2 is opened. If the relay circuit should fail, the engine can be stopped immediately by opening the safety switch 12.

In the first embodiment, the relay circuit is disabled if either the engine oil temperature or the exhaust temperature is below a certain temperature. A device that does not stop the engine unless both of the temperatures are below a certain level will be explained based on FIG. 2.

FIG. 2 shows a second embodiment, and the difference from the first embodiment is that the first bimetal switch 23
and the second bimetal switch 24 are connected in parallel. The other configurations are substantially the same as those of the first embodiment. According to this embodiment, when the engine is running and the oil temperature is high and the first bimetal switch 23 is closed and the exhaust gas temperature is high and the second bimetal switch 24 is closed, the relay 13 is also closed and the key switch 2 is closed. Even if it is opened, there is a bypass circuit, so the engine will not stop, but the relay will not be activated until the oil temperature drops below a certain temperature and the first bimetal switch opens, and the exhaust temperature drops and the second bimetal switch 24 opens. 13 is also opened and the engine stops.

As described above, according to the present invention, even if the key switch is opened (off) after the engine is running, the engine will not stop if the engine is not slowly cooled, and if the oil temperature or exhaust temperature or both drop, the engine will stop. Since it is configured to automatically stop, the life of the turbocharger bearings is extended, and the durability of the engine itself can be increased. Moreover, if necessary, the engine can be immediately stopped even immediately after high-load or high-speed operation.

Although the present invention includes both a first bimetal switch for sensing engine oil temperature and a second bimetal switch for sensing exhaust temperature, it goes without saying that either one of them may be used.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, FIG. 1 is a circuit diagram showing the first embodiment, and FIG. 2 is a circuit diagram showing the second embodiment.
FIG. 2 is a circuit diagram showing an example. ...Start, stop circuit, B...Battery, 2...
... Key switch, 3 ... Starter, 4 ... Engine stop device, 5 ... First terminal, 7 ... Second terminal, ... Relay circuit, 12 ... Safety switch,
13... Relay, 21... Relay contact, 22...
Relay coil, 23...first bimetal switch, 24...second bimetal switch, 25...
Too bad.

Claims (1)

[Scope of utility model registration request] In a stopping device for a turbocharged diesel engine that has a key switch in the circuit for starting and stopping the engine, a relay contact is connected in parallel with the key switch, and the relay coil that opens and closes the relay contact is connected to the engine oil temperature or A stopping device for a diesel engine with a turbocharger, which is connected to a switch that opens and closes by sensing the temperature.