JPS5950871B2 - Device for removing deposits in the combustion chamber of an internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for removing deposits that accumulate within the combustion chamber of an internal combustion engine.

Increasing the compression ratio is an effective way to increase the thermal efficiency of an internal combustion engine and reduce fuel consumption.

Therefore, gasoline with a high octane number that does not cause knocking even at high compression ratios is required.

However, from the perspective of oil refining technology and the thermal efficiency of internal combustion engines, it is not advisable to pursue the development of high-octane gasoline when considering the conservation of resources and energy for society as a whole. 96RON
(Research Method Octane Number) is said to be the best.

On the other hand, as the mileage of a vehicle increases, that is, as the internal combustion engine is used, deposits that are considered to be incomplete combustion of fuel and lubricating oil accumulate on the top of the combustion chamber and on the upper surface of the piston.

These deposits reduce the anti-knock performance of the engine, and for example, when examining the reduction in anti-knock performance with respect to the required octane number of the engine, the required octane number (ONR) of the engine is determined at the time when the vehicle has traveled between 5,000 and 110,000 km. Compared to that, it increases by about 6 octane.

For this reason, the current engine compression ratio is set by taking into consideration the octane number of commercially available gasoline as well as the increase in the required octane number of the engine.

That is, the compression ratio of the engine needs to be set to a lower value by the amount of increase in the required octane number due to use.

Therefore, when the engine is first used, the engine is operated at a lower compression ratio, even though it is possible to increase thermal efficiency by operating the engine at a higher compression ratio.

The accumulation of deposits within the combustion chamber also increases the proportion of harmful components in the exhaust gas.

An object of the present invention is to prevent or remove deposits from accumulating in the combustion chamber, and thereby to enable the engine to be operated at an appropriately high compression ratio from the beginning of use. It is.

Next, the present invention will be described in detail with reference to the drawings.

Each cylinder 2 of a four-cylinder internal combustion engine 1 for a vehicle. 3. 4.5 have spark plugs 6 and 7 respectively. 8. 9 are provided, and these spark plugs 6, 7. 8. 9 is connected to an ignition device 11.

The ignition device 11 responds to a control signal sent from the ignition timing control device 12 to activate the spark plugs 6, 7. 8.
Send energizing current to 9.

13 is a sensor that detects the vehicle speed, 14 is a sensor that detects the rotational speed of the engine 1, 15 is a sensor that detects the intake pipe negative pressure, that is, the load of the engine 1, and 16 is a sensor that detects the distance traveled by the vehicle. be.

Outputs from the vehicle speed sensor 13 , rotational speed sensor 14 , intake pipe negative pressure sensor 15 , and mileage sensor 16 are sent to the ignition timing control device 12 .

Under normal conditions, the ignition timing control device 12 controls the ignition timing of each cylinder 2, 3. The angle is determined and a control signal is sent to the ignition device 11, thereby causing the spark plugs 6, 7. 8. 9 is discharged at an advance angle determined by the ignition timing control device 12.

In this normal state, the combustion chamber 2. 3. 4. 5
No knocking occurs.

During normal operation of internal combustion engine 1, cylinder 2. 3. At 4.5, incomplete combustion products, or deposits, are formed on the upper surface of the piston and the top of the combustion chamber.

The ignition timing control device 12 receives signals from, for example, a vehicle speed sensor 13, a rotational speed sensor 14, an intake pipe negative pressure sensor 15, and a mileage sensor 16 to determine a predetermined vehicle speed, a predetermined rotational speed of the engine, and a predetermined load of the engine. , and an operating parameter of the engine, such as the distance traveled by the vehicle, and determines the progress in normal conditions in response to one of these operating parameters or in response to a predetermined state determined in relation to two or more operating parameters. Spark plugs 6, 7 at an advance angle that is advanced by a predetermined value from the angle. 8. A control signal is sent to the ignition device 11 so that the ignition device 9 is energized.

In this way, the spark plugs 6, 7. at an advance angle advanced from the normal advance angle. 8. 9 is energized, and the air-fuel mixture in the cylinder corresponding to that spark plug is ignited at an advance angle that is advanced by a predetermined value from the normal advance angle, and knocking occurs in this cylinder.

As a result of this knocking, the deposits that had adhered to the top of the combustion chamber or the top of the piston just before the knocking are peeled off and discharged from the combustion chamber through the exhaust port.

The process by which deposits are removed from the walls of the combustion chamber due to knocking is not well understood, but knocking generates high heat and large shock waves (vibrations), and these act synergistically to burn the deposits. It is assumed that it was removed from the chamber board.

The greater the advance value than the normal advance angle, the greater the degree of knocking that occurs.

Knocking usually leads to engine damage or reduced operating performance.

Therefore, taking these things into account, the advance angle or number of occurrences for knocking is selected.

In this way, according to the present invention, by intentionally causing knocking, the deposits accumulated in the combustion chamber can be removed.
Alternatively, deposition can be prevented.

Therefore, since the required octane number increases with the distance traveled by a car, engines that were previously designed with a correspondingly smaller compression ratio can now be set to the most suitable compression ratio in the absence of deposits. .

Therefore, fuel consumption can be reduced, and engine performance and driving performance, which conventionally deteriorated as the mileage increases, can be improved.

Furthermore, since no deposits are generated in the combustion chamber, the emission of harmful components can also be suppressed.

[Brief explanation of drawings]

The drawings schematically depict embodiments of the invention. 1...4-cylinder internal combustion engine, 2. 3. 4. 5
・・・・・・Cylinder, 6. 7. 8. 9...
Spark plug, 11... Ignition device, 12...
...Ignition timing control device, 13...Vehicle speed sensor,
14... Engine rotation speed sensor, 15...
-Intake pipe negative pressure sensor, 16... mileage sensor.

Claims (1)

[Claims] 1. A spark plug installed in each cylinder of the internal combustion engine, an ignition device that energizes the spark plug at an advance angle appropriate for the current driving condition of the vehicle, and an ignition device that responds to at least one of the operating parameters of the engine. , a deposit in a combustion chamber of an internal combustion engine, characterized in that the ignition device advances the advance angle when energizing the spark plug by a predetermined value, thereby causing knocking in a predetermined cylinder. removal device.