LT5490B - A sparking-plug - Google Patents

Abstract

Sparking plug on internal - combustion engine comprises in operating part a central electrode, a thermal cone of ceramic insulator with end discharge surface, an operating chamber and a metal frame with concentrator of electromagnetic field which creates with central electrode an airy surface spark gap. New is what an operating part of sparking plug is prolonged and an operating chamber is pre chamber shaped with muzzle. Operating part of a frame is hemispherical and has stated irregularity, which are hemisphere shaped grooves. A central electrode, end surfaces of operating part of frame and insulator of thermal cone form a central spheral groove.

Description

The invention relates to the machinery manufacturing industry, in particular to devices for igniting a combustible mixture in internal combustion engines.

A classic spark plug is known, having a housing, an insulator, a central electrode, and a side electrode forming a spark gap with the center electrode end.

this structure has been unchanged for over 100 years.

However, as the technology progressed, some of its disadvantages became unacceptable. First of all, the short lifetime associated with the limited surface area of the electrode spark surfaces. Second, the dependence of the ignition properties of the candle on the position of the lateral electrode in the combustion chamber relative to the vortex direction of the combustion chamber. Third, the candle forms a noticeable gas dynamic interference near the walls of the combustion chamber. Fourth, the spark has an inadequate spark gap at the applied puncture voltage. This reduces the spark plug property. By increasing the spark gap, the spark does not form between the electrodes, but passes through the contaminated surface of the ceramic insulator thermal cone. This, in turn, causes the motor to be arrhythmic and reduces all its characteristics.

Multi-electrode spark plugs are widely used in this meu (see Οβθμμ 3a> KMraHMfl φιιρΜΗ NKG, 2006). In these, a spark discharge occurs between the lateral surface of the central electrode and the end surfaces of the lateral electrodes. This has resulted in a significant increase in the life of the candle and a reduction in the dependence of the candle's ignition characteristics on its angular position. However, in comparison to the classic candle, all other flaws remained virtually unchanged.

Surface discharge plugs are also known (see, for example, EP1202411 B1, TPKKI H01T 13/52, 2003). In these, the spark discharge occurs exclusively on the surface of the ceramic insulator between the central electrode and the annular electrode of the housing. In addition, a large spark gap is obtained, with a relatively low burst voltage, an increase in the life of the spark plug, its efficiency independent of its angular position in the combustion chamber, and low gas dynamic interference. However, the spark temperature decreased significantly, which reduced the ignition properties of the spark and worsened the cleaning of the insulator discharge surface.

Spark plugs with combined spark gap have recently become popular (see, for example, EP0872927 B1, TPKI H01T 13/20, 2003).

The spark passes through the lateral surface of the central electrode, at the end of the thermal cone of the insulator, and then through the air to one of the lateral electrodes. Such a solution allows for a wide choice of spark gap lengths and puncture voltages, i.e. spark temperature. However, other disadvantages of multi-electrode candles persist.

The closest device to the present invention according to the technical solution is a spark plug described in Russian patent RU2175160 C1, H01T 13/00, 2000. It comprises a central electrode, a thermal cone of a ceramic insulator with a rear discharge surface, a working chamber, and a metal housing with an electromagnetic field concentrator forming an air-surface spark gap with the central electrode. This candle has a long service life, independent of the ignition properties from the angular position of the candle, low gas dynamic interference, high ignition capacity due to the long and hot spark ideally achieved by the flammable mixture.

However, this technical solution is not without its drawbacks. First, the combustible mixture ignites at the level of the combustion chamber wall. This increases the thermal loss on the combustion chamber wall, extends the combustion time of the mixture and increases combustion asymmetry. Second, flammable and other dirt builds up on the lateral surface of the thermal cone of the insulator, causing undesirable consequences.

The object of the present invention is to eliminate the above-mentioned drawbacks and to achieve the best performance of an internal combustion engine.

This object is achieved by the fact that according to the present invention the spark plug of the internal combustion engine, the working part of which has a central electrode, a thermal cone of a ceramic insulator with a rear discharge surface, a working chamber and a metal housing with an electromagnetic field concentrator forming an air-surface spark the working part is extended and the working chamber is in the form of a pre-chamber with a nozzle.

By the way:

the outside of the housing working portion is hemispherical, the housing housing operating portion has regular irregularities, the irregularities are in the form of hemispherical recesses, the central surfaces of the central electrode, the thermal cone of the insulator and the housing working portion form a central spherical recess.

The essence of the present invention is as follows.

The elongated working part allows the ignition mixture to be moved from the combustion chamber wall to the depth of the inlet. This will reduce heat loss on the wall of the combustion chamber, reduce combustion time and combustion asymmetry of the mixture, which is important in high engine speeds and loads.

The combustion chamber in the form of a nozzle chamber gives a double effect. First, the high-temperature, high-speed jet of hot gas provides automatic cleaning of the side surface of the thermal cone in the nozzle area. In this way, the new candle gives the double effect of the self-cleaning of the thermal cone; the rear is surrounded by a surface spark discharge and the side by a jet of jet gas. Second, the new spark plug is a dual action ignition ignition device: passive - directly from the spark, but in this case, the spark is long and hot, and active due to the pre-chamber effect. In this way, the efficiency of the candle of the present invention is greatly increased. The first method of ignition will prevail during engine start-up, idle and low loads. For heavy loads - second.

The outer part of the working part of the hemispherical body provides the least aerodynamic resistance, i.e. the minimum gas dynamic interference in the combustion chamber.

The formation of regular irregularities on the outer surface of the housing working portion reduces the effect of aerodynamic interference. The microturbulence resulting from these irregularities plays the role of an "air bearing".

Regular irregularities of hemispherical excavations are the simplest and most technological solution to this task.

The hemispherical center electrode end faces, the insulator thermal cone, and the housing working part all solve several tasks simultaneously. First, the spherical recess forms a "microclimate" without fuel droplets with a quality combustible mixture. Secondly, the spark blowing effect is eliminated, which is important for the self-cleaning of the insulator thermal cone end surface. Third, the effect of reflection and focusing of all kinds of spark discharge from the thermal cone of the insulator and the curved end surface of the central electrode is exploited. This will further increase the inflammatory effect of the candle.

The invention will now be explained with reference to Figure 1, which shows a simplest embodiment of a spark plug.

Fig. 2 illustrates an optimum embodiment of the spark plug.

The working part of the spark plug has a central electrode 1, a thermal cone 2 of a ceramic insulator 3 with a discharge surface 4, a working chamber 5 in the form of a pre-chamber 6 and a nozzle 7 and a working part 8 with an electromagnetic field concentrator 10 The exterior surfaces 13, 4 and 14 of the central electrode 1, the thermal cone 2 of the insulator 3 and the working portion 8 of the housing 9 together form a central spherical cutout 15.

The spark plug works as follows. During the compression stroke, the pressure of the combustible mixture in the combustion chamber increases. This causes the mixture to be sprayed into the pre-chamber 6 via nozzle 7. At the same time, the quality of the mixture improves. At the end of this process, at a certain point in time (ignition advance angle), a high voltage pulse is applied to the central electrode 1 relative to the metal body 9, which ionizes the gas in the spark gap 11. Since the dielectric constant e At surface 2, 4 occurs much more intensively than at the air gap, so the breakdown voltage is largely determined by the size of the air gap (from concentrator 10 to end surface 4). Spark discharge, due to the high reflectivity properties of the combined spark gap 11, surfaces 4 and 13 and good access to the ignition focal, ignites the mixture reliably and steadily over a distance from the wall. The flame spreads very quickly and symmetrically in the combustion chamber.

In addition, the mixture in the pre-chamber 6 is ignited. As the mixture is combusted in the pre-chamber 6, the gas pressure in the chamber increases substantially and a stream of high temperature combustion products is discharged into the combustion chamber through the nozzle 7. This causes even more intense combustion of the mixture in the combustion chamber even further away from the wall. The working part 8 of the body 9 of the hemisphere and the spherical recesses 12 made therein gives an “aerodynamic transparency effect”.

The spark plug of the present invention achieves its objectives and is far superior to known solutions in all engine operating modes. This has been conclusively proven by testing on different types of internal and external combustion engines.

Claims (5)

DEFINITION OF INVENTION 1. A spark plug for internal combustion engines having a central electrode, a ceramic insulator with a thermal discharge cone with a rear discharge surface, a working chamber, and a metal housing with an electromagnetic field concentrator forming, together with the central electrode, a spark air gap, that the working portion of the spark plug is extended and that the working chamber is in the form of a pre-chambered nozzle. 2. A candle according to claim 1, characterized in that the outside of the working part of the housing is hemispherical. 3. Candle according to claim 1 or 2, characterized in that the working part of the housing has regular irregularities on the outside. A candle according to claim 3, characterized in that the irregularities are in the form of spherical recesses. 5. A candle according to claims 1-4, characterized in that the end surfaces of the central electrode, the thermal cone of the insulator and the working part of the housing form a central spherical indentation.