RU66120U1 - SPARK PLUG - Google Patents

Abstract

The spark plug contains a housing 1 with an external threaded girdle 2 and with a longitudinal hole 3, in which an insulator 4 with a central electrode 5 is placed. The mass electrode is made in the form of a nozzle head 6 extending beyond the central electrode 5 with a diffuser 7 at the outlet, which is placed in diffuser 7 of the spark gap between the electrodes 5, 6 (since the last is the nozzle head). The nozzle head 6 is integral with the housing 1, its length from the edge of the threaded girdle 2 of the housing 1 is, for example, 12 mm, i.e. made at least the minimum diameter of the diffuser 7, equal, for example, 7 mm The angle of the diffuser 7 is made equal to (51 ± 1.5) °, and the length is not more than 0.5 of the minimum diameter of the diffuser 7. The insulator 4 is equipped with an external seal 8 made of heat-resistant silicone for sealing against the surface of the longitudinal holes 3 of the housing 1. The nozzle head 6 is made with an inner chamber 9 expanding in a direction opposite to the direction of expansion of the diffuser 7. The chamber 9 is made with radial holes 10 inclined to its axis and with a side wall, the thickness of which increases in the direction of the threaded girdle 2 of the housing 1. The chamber 9 is made with an annular conical wall 11 from the side opposite to the diffuser 7. The wall 11 of the chamber 9 is made with an obtuse narrowing angle to the axis of the housing 1. The spark gap around the electrode 5 in the cross section of the minimum diameter of the diffuser 7 is 0.25-0.45 of this diameter , thanks to the continuous casing 1 and the diffuser 7, the working range of the spark covers 360 °. The free end of the central electrode 5 projects into the diffuser 7 by no more than 0.5 mm. Thus, an effective, reliable and durable spark plug was created and the arsenal of spark plugs was expanded.

Description

The invention relates to devices for igniting an air-fuel mixture in combustion chambers of engines operating without self-ignition of this mixture, mainly for injection and carburetor internal combustion engines (ICE) operating on light fuel. A serious load is placed on the candles during the operation of the engine: the cyclical effects of high voltages, operation at low and high temperatures, the pressure of expanding gases, a wide range of engine conditions, deposits of combustion products, electroerosion, etc.

Known spark plug for an internal combustion engine, comprising a housing with a chamber and a hole, a central electrode with an insulator, a spark gap, characterized in that the spark gap is made in the form of an annular gap formed by the edge of the end face of the central electrode and the edge formed by the hole in the housing and the inner surface the chamber of the candle, and the end of the central electrode is placed inside the chamber, and the ratio of the parameters of the spark gap is determined by the formula:

where A is the difference between the radii of the central electrode and the hole; B is the distance from the plane of the end face of the electrode to the plane of the surface of the chamber; C is a constant value of the spark gap, and the hole in the body is made in the form of a truncated cone, and the diameter of the central electrode is greater than the diameter of the hole in the body by at least two sizes of the spark gap - 2C. (RU No. 2282290, 2006)

During the operation of a well-known candle, the spark in time is very long and the same, regardless of engine speed. When the breakdown of the spark begins, the mixture begins to ignite in the combustion chamber, and since the vortex is strong and the spark is long in time, there is a constant ignition of the combustible mixture, a gradual combustion of the mixture on one side of the cylinder is obtained. Due to the long spark, it forms

tail. That is, on one side of the combustion chamber, the mixture is almost burnt out, and on the other, the mixture has not yet ignited. The asymmetry of combustion is formed, the direction of the flame front during the development of combustion of the air-fuel mixture is determined by vortex flows, which causes mechanical losses. When the rest of the mixture begins to ignite, an explosion occurs and the pressure on the piston rises equivalent to hitting the edge of the piston. Explosion causes uneven pressure on the piston. At this moment, the piston is jammed, because on one side the fuel has already burned out, but on the other there is no, there is a skew. On the used pistons, on the one hand, there are obvious scratches, and on the inner surface of the cylinder on the same side, the first compression ring is filled with a groove, which speak of this jamming. In addition, another serious problem arises related to the uneven combustion of the air-fuel mixture in the combustion chamber: due to the fact that the ignition of the air-fuel mixture must coincide with the piston reaching its upper position, it is necessary to pre-ignite it, because ignition does not occur in the center of the combustion chamber, the vortex flow picks up the flame and carries it along its path along the walls of the combustion chamber. In this case, the gases formed as a result of combustion create additional resistance to the piston that has not yet reached its extreme position. As a result, energy is lost and engine efficiency is reduced.

Also known is a spark plug for an internal combustion engine, comprising a housing, an insulator with a central electrode located in the housing and a mass electrode mounted on the housing to form a spark gap between the electrodes, the candle being provided with a nozzle nozzle fixed in the housing, characterized in that, for the purpose improve operational characteristics, the central electrode is equipped with a cone-shaped tip, the apex of which is directed towards the nozzle nozzle cut side, the mass electrode is made in the form of nozzles This nozzle is of the Laval nozzle type and forms a nozzle with a central body with the tip of the central electrode, while the tip of the central electrode is placed between the critical section of the Laval nozzle and its cut with the formation of a spark gap between the nozzle wall and the tip. (RU No. 2055432, 1996, prototype).

The disadvantages of the known spark plugs are low reliability due to the effects of vortex flows generated during engine operation, incomplete fuel combustion due to the large distance from the spark gap to the center of the combustion chamber and the need to use catalysts to reduce exhaust toxicity, insufficient heat removal from mass electrode, instability of spark discharge and operation on a rich mixture, insufficient life due to breakthrough of hot gases between the insulator and the housing: During operation candles ceramic insulator begins to "hang out" in a metal case. As a result, gases begin to erupt from the combustion chamber between the metal casing and the ceramic insulator. Gases blow off the spark and the candle starts to work unstably, the probability of uptime and its life is reduced.

The technical task of the utility model is to create an effective, reliable and durable spark plug and expand the arsenal of spark plugs.

The technical result that provides a solution to the problem, is that provided:

- protection of the spark and the initial ignition of the air-fuel mixture from the vortex flows generated during engine operation;

- the ability to reach the center of the combustion chamber, so that the air-fuel mixture is ignited at the axis in the center of the combustion chamber. Due to this, almost all fuel burns in the combustion chamber. As a result, fuel consumption is reduced, significant dynamics appear, the maximum speed increases, the toxicity of exhaust gases decreases, practically no deposits are formed on the piston bottom and on the walls of the combustion chamber;

- there is no need to use a catalyst to reduce exhaust toxicity, since almost complete combustion of the air-fuel mixture is achieved;

- the thickness of the candle head allows you to remove excessive heat when igniting the air-fuel mixture;

- the size of the spark gap guarantees stable operation of the spark, it is not afraid of “filling” the candle;

- the maximum possible incendiary ability in all engine modes;

- the candle is not “afraid” of pollution from the rich mixture and the ingress of oil, coolant and low-quality gasoline;

- the candle has the ability to self-clean;

- the maximum possible tightness of the spark plug, regardless of operating time;

- stability of the spark discharge. The result is increased likelihood of uptime and lifespan.

The essence of the utility model consists in the fact that the spark plug contains a body with an external threaded girdle and with a longitudinal hole in which an insulator with a central electrode is placed, and a mass electrode made in the form of a nozzle head protruding outside the central electrode with a diffuser at the outlet located the formation of a spark gap between the electrodes in the diffuser, moreover, the nozzle head is integral with the housing, its length from the edge of the threaded girdle of the housing is made not less than the minimum diameter of the diffuser, the expansion angle of which is made equal to (51 ± 1.5) °, and the length is not more than 0.5 of the minimum diameter of the diffuser, while the insulator is equipped with an external seal of heat-resistant silicone for sealing relative to the surface of the longitudinal opening of the housing.

Preferably, the nozzle head is made with an inner chamber expanding in a direction opposite to the direction of expansion of the diffuser, the inner chamber of the nozzle head is made with radial holes inclined to its axis, the inner chamber of the nozzle head is made with a side wall, the thickness of which increases in the direction of the threaded girdle of the housing, inner the nozzle head chamber is made with an annular conical wall on the side opposite to the diffuser, and the annular conical wall of the inner measures the nozzle is formed with an obtuse angle to the axis of the housing constriction. In special cases of execution, the spark gap in the cross section of the minimum diameter of the diffuser is 0.25-0.45 of this diameter, and the end of the central electrode protrudes into the diffuser by no more than 0.5 mm.

The drawing of figure 1 shows a structural diagram of the spark plug, figure 2 - scheme of circulation of the air-fuel mixture and the operation of the candle with its central location in the combustion chamber, figure 3 - scheme of circulation

air-fuel mixture and the operation of the candle with its lateral location in the combustion chamber.

The spark plug contains a housing 1 with an external threaded girdle 2 and with a stepwise longitudinal hole 3, in which a step insulator 4 with a central electrode 5 mounted along its axis is placed. The mass electrode is made in the form of a nozzle head 6 protruding beyond the limits of the central electrode 5 with a diffuser 7 at the outlet, which forms a spark gap between the electrodes 5, 6 in the diffuser 7 (since the nozzle head is the last). The nozzle head 6 is integral with the housing 1, its length from the edge of the threaded girdle 2 of the housing 1 is, for example, 12 mm, i.e. made at least the minimum diameter of the diffuser 7, equal, for example, 7 mm The angle of the diffuser 7 is made equal to (51 ± 1.5) °, and the length is 2-3.5 mm, i.e. not more than 0.5 of the minimum diameter of the diffuser 7. The insulator 4 is equipped with an external seal 8 of heat-resistant silicone for sealing relative to the surface of the longitudinal holes 3 of the housing 1.

The nozzle head 6 is made with an inner chamber 9 expanding in a direction opposite to the direction of expansion of the diffuser 7.

The camera 9 is made with radial holes 10, inclined to its axis and with a side wall (not indicated), the thickness of which increases in the direction of the threaded girdle 2 of the housing 1.

The chamber 9 is made with an annular conical wall 11 from the side opposite to the diffuser 7. The wall 11 of the chamber 9 is made with an obtuse narrowing angle to the axis of the housing 1.

The spark gap around the electrode 5 in the cross section of the minimum diameter of the diffuser 7 is 2-2.5 mm, i.e. 0.25-0.45 of this diameter, thanks to the solid body 1 and the diffuser 7, the working range of the spark covers 360 °

The free end of the central electrode 5 projects into the diffuser 7 by no more than 0.5 mm. All quantitative ratios were obtained empirically by selecting the optimal ratios, absolute sizes and angles.

The candle is screwed screwed to the end of the girdle 2 into the wall of the combustion chamber 12. In this case, the nozzle head 6 protrudes into the volume of the chamber 12.

The spark plug works as follows.

When filling with the fuel mixture the combustion chamber 12 of the internal combustion engine or during the compression stroke in the internal combustion engine, the cavity of the chamber 9 of the candle is also filled with this mixture. During

movement of the piston (not indicated) to the upper position in FIGS. 2, 3, the air-fuel mixture is compressed in the combustion chamber 12. When a high voltage pulse is applied to electrodes 5 and 6, an electrical breakdown occurs in the zone of the spark gap between them. At first, this breakdown has the form of a spark cord, but then under its ionizing effect, the breakdown almost instantly spreads to all annular volumes in the head 6, in Fig. 1, in the plane perpendicular to the central electrode 5. Immediately under the action of the electrodynamic force resulting from the interaction the radial current passing through the plasma formed during the breakdown, and the annular magnetic field created by the same current flowing further along the central electrode 5, the plasma bunch begins to accelerate in ol axis of the diffuser 7, i.e. there is a movement ("blowing") of the plasma bunch to the outer end of the head 6. As a result, the size of the ring discharge increases and it moves through the working mixture in the volume of the nozzle nozzle, which leads to ignition of this mixture not along the line (cord), but practically throughout the nozzle nozzle, which significantly increases the reliability of ignition. At the same time, the fuel mixture ignites on the other side of the critical section of the diffuser 7 of the head 6, i.e. in the chamber 9. Ignition of the fuel mixture in the chamber 9 causes the stream of combustion products to flow out from the diffuser 7 at a high speed, mixes with the fuel mixture in the volume of the ICE combustion chamber 12, and completes the process of its ignition, initiated by the “blown” plasma clot.

The conical exit of the diffuser 7 allows you to feed more air-fuel mixture into the chamber 9 of the candle, thus, in the chamber 9, the concentration of the air-fuel mixture is higher than in the chamber 12 of the combustion.

The vortex formed in the combustion chamber 12 carries away heat from ordinary candles. The speed of the vortex is maximum precisely at the walls of the combustion chamber 12, where spark gap is located for known candles. The spark gap of the inventive candle is protected from this vortex and retains heat, which increases the efficiency ignition of the air-fuel mixture in the combustion chamber.

In this case, the spark gap is located in the central zone of the combustion chamber 12 and is protected by the housing 1 from the vortex flows of the air-fuel mixture. This ensures constant stable ignition of the air-fuel mixture. When starting a cold engine, the cone of the diffuser 7, the central electrode 5 and the insulator

4 of the central electrode 5 are heated during the first three cycles, which creates ideal conditions inside the candle (there is no heat loss to the environment of the combustion chamber 12) for igniting the air-fuel mixture in the spark gap region and, also, in the candle chamber 9.

The seal 8 prevents the breakthrough of gases from the combustion chamber 12 between the metal housing 1 and the ceramic insulator 4. Even if the ceramic insulator 4 begins to “hang out” in the metal housing 1, the gases cannot escape. Therefore, the candle is stable for a long time and does not fail.

The size of the spark gap also allows the spark to work stably. The candle is not afraid of the ingress of oil, coolant, low-quality gasoline and “flooding”, which is important when the engine is cold started, especially at low ambient temperatures. The spark gap in the narrow part of the diffuser 7 allows you to effectively ignite the air-fuel mixture in the chamber 9 of the candle, which is also relevant when the engine is cold started. When the ignition of the air-fuel mixture occurs in the place of the spark gap, the flame from the candle does not exit into the combustion chamber 12, but goes inside the candle due to the piston moving and compressing. In the chamber 9, which tapers towards the exit, energy is accumulated. When it reaches a critical mass, it shoots with a large volume of fire, and the conical exit of the diffuser 7 increases the power of the flame to the center of the combustion chamber. One of the main advantages of such a flare ignition is its maximum incendiary ability. The torch is able to overcome noticeable distances both across and towards the whirlwind. Due to this, a large volume of the air-fuel mixture is immediately ignited in the combustion chamber, which significantly accelerates its more complete combustion. Thus, the time of ignition of the air-fuel mixture in the center of the combustion chamber is reduced by about 3 times.

The spark gap of our candles is closed by a housing that protects the ignition from vortex flows. It shoots accumulated energy from the cavity of the candle into the center of the combustion chamber towards the vortex flows, significantly reducing the path of the flame to the center of the combustion chamber. This reduces the ignition time in the center of the combustion chamber by about 3 times. Accordingly, the ignition of the air-fuel mixture occurs when the piston reaches its upper extreme position. Due to this, there is practically uniform combustion of the mixture, due to which there is a uniform pressure of the expanding gases on the piston. At

This eliminates mechanical losses, namely: jamming and excessive pressure on the piston to reach the upper extreme position. At the same time, the maximum speed increases significantly, fuel economy, exhaust toxicity decreases, and the need to install a catalyst is eliminated.

Thus, an effective, reliable and durable spark plug was created and the arsenal of spark plugs was expanded.

Claims (8)

1. Spark plug comprising a housing with an external threaded girdle and with a longitudinal hole in which an insulator with a central electrode is placed, and a mass electrode made in the form of a nozzle head protruding beyond the limits of the central electrode with a diffuser at the outlet, which forms a spark gap in the diffuser between the electrodes, characterized in that the nozzle head is integral with the housing, its length from the edge of the threaded girdle of the housing is made not less than the minimum diameter of the diffuser, the expansion angle of which made equal to (51 ± 1,5) °, and the length is not more than 0.5 of the minimum diameter of the diffuser, wherein the insulator is provided with a refractory outer seal of silicone for sealing the housing relative to the surface of the longitudinal hole. 2. The candle according to claim 1, characterized in that the nozzle head is made with an internal chamber expanding in the direction opposite to the direction of expansion of the diffuser. 3. The candle according to claim 2, characterized in that the inner chamber of the nozzle head is made with radial holes inclined to its axis. 4. The candle according to any one of paragraphs.2 and 3, characterized in that the inner chamber of the nozzle head is made with a side wall, the thickness of which increases in the direction of the threaded girdle of the housing. 5. The candle according to any one of paragraphs.2 and 3, characterized in that the inner chamber of the nozzle head is made with an annular conical wall on the side opposite to the diffuser. 6. The candle according to claim 5, characterized in that the annular conical wall of the inner chamber of the nozzle head is made with an obtuse narrowing angle to the axis of the housing. 7. A candle according to any one of claims 1 and 2, characterized in that the spark gap in the cross section of the minimum diameter of the diffuser is 0.25-0.45 of this diameter. 8. A candle according to any one of claims 1 and 2, characterized in that the end of the central electrode protrudes into the diffuser by no more than 0.5 mm.