CN106936071B - A kind of spark plug and the application method for extending pancake engine spark plug life - Google Patents

Abstract

The invention discloses a spark plug, which comprises a central electrode and an insulator. The central electrode is arranged inside the insulator and extends out of the insulator along its axial direction. The lower end of the insulator is covered with a metal shell, and the lower end of the metal shell It is a threaded structure, the ground electrode is L-shaped, there is a gap between the ground electrode and the central electrode, the discharge electrode of the central electrode is split into multiple ends, and the multiple ends are evenly distributed on the discharge electrode of the central electrode. It also discloses A usage method for prolonging the service life, the method is to exchange the positions of the spark plug on the upper part and the lower part of the horizontally opposed engine after using for a certain period of time. The invention can reduce the flame-extinguishing effect of the ground electrode and improve the flashover stability of the spark plug.

Description

A kind of spark plug and the using method of prolonging the service life of horizontally opposed engine spark plug

technical field

The invention relates to the field of engines, in particular to a spark plug and a method for prolonging the service life of the spark plug of a horizontally opposed engine.

Background technique

The spark plug is commonly known as the burner, and its function is to discharge the pulsed high-voltage electricity sent by the high-voltage wire, break down the air between the two electrodes of the spark plug, and generate an electric spark to ignite the mixed gas in the cylinder.

The ignition speed of the existing spark plug is relatively slow, and there are many carbon deposits on the electrode, which makes the flashover performance of the spark plug unstable. Moreover, the anti-oxidation ability of ordinary spark plugs is limited, the electrodes are severely ablated, and the service life is not long.

The working environment of the spark plug is extremely harsh, and the temperature and pressure are not only high but also change frequently.

In order to increase the anti-knock ability of gasoline, modern piston aircraft engines require the use of high-octane aviation gasoline. Most domestic aviation gasoline meets the anti-knock high-octane requirements by adding lead-containing chemical anti-knock agents. At present, the lead content of domestic aviation gasoline No. 100 or No. 95 is relatively high.

This kind of high temperature and high pressure working environment and relatively inferior fuel can easily cause spark plug bridging short circuit, electrode ablation, carbon deposition, lead deposition, oil hanging and other pollution, which will seriously affect the ignition performance of the spark plug. For this reason, it is necessary to improve the ability of the spark plug to remove carbon deposits, and to improve the use method of the spark plug of the horizontally opposed engine.

The existing method of use needs to check the spark plug every 50 hours. The inspection steps are generally cleaning according to the situation, flashover test, and then randomly reinstalling or reinstalling in situ.

This inspection and maintenance method ignores that the working environment of the spark plug in the lower part of the cylinder is worse than that in the upper part, and the various losses are more serious, and the service life is relatively shorter. Lead deposits, carbon deposits, and oil will weaken the spark generated by the spark plug. Even if there is no flashover, because the electric spark is weak or there is no flashover at all (all or part of the spark plug), the explosion pressure of each cylinder will be uneven or not burst, which will cause the engine to shake.

Contents of the invention

The purpose of the present invention is to provide a spark plug, which can increase the ignition speed faster and can better ensure the stability of flashover. The invention also provides a usage method capable of prolonging the service life of the spark plug of the horizontally opposed engine.

The present invention realizes through following technical scheme:

A spark plug includes a central electrode and an insulator, the central electrode is arranged inside the insulator and extends out of the insulator along its axial direction, the lower end of the insulator is covered with a metal shell, and the lower end of the metal shell is a threaded structure, And the lower end of the metal shell is connected with a ground electrode, there is a gap between the ground electrode and the central electrode, the discharge electrode of the central electrode is bifurcated into 2 ends, and the 2 ends are evenly distributed on the discharge electrode of the central electrode, each The end face of the terminal is inclined, the ground electrode is L-shaped, and the number of ground electrodes is equal to the number of ends, and the position of each ground electrode is opposite to each end, and the end face of each ground electrode is also inclined and The end faces of each end are parallel with a gap.

The ignition surface between the central electrode and the ground electrode of the existing spark plug, the number of ground electrodes can be multiple, but the central electrode only has one discharge end, and there is always only one ignition surface, and the ignition surface is only limited to one place. Spreads quickly to the ignition surface and takes longer to reach ignition temperature during full ignition.

In the present invention, the central electrode is arranged to have two ends, and the end faces of the two ends can constitute the ignition surface, and the ends correspond to the same number of grounding electrodes, and the end faces of the ends and the end faces of the grounding electrodes are both arranged as There are opposite slopes with a certain gap, and the two ends are set for splits, with a certain distance, so that two ignition surfaces are formed, and the entire space range between the central electrode and the ground electrode can be taken into account, and two ignition surfaces can be ignited at the same time There is a certain distance between the surfaces, and there is an area where thermal reactions intersect during the ignition process. In this area, the temperature rises faster and reaches the ignition point of the mixed gas faster. This setting breaks the current technology that limits the ignition surface to a certain place. The limitation of being able to jump between the center electrode and the ground electrode is easier and burns faster. The distance between the other two ignition surfaces is also exquisite. If they are too close together, it is easy to burn the two central electrodes and the ground electrode, and if they are too far together, they cannot play a synergistic effect. The distance at which the ignition surface has no synergistic benefit is D1, the distance between the two gaps just enough to cause the central electrode and the ground electrode to burn is D2, and the center distance between the two gaps (that is, the gap between the central electrode and the ground electrode) of the present invention is set to D , then D satisfies D1>D>D2, and D=the diameter of the central electrode+0.6-1.5mm. There is no relevant discussion in the existing technology.

The end face of each end is a V-shaped face.

The end surface of each ground electrode is a V-shaped surface, and the groove position of the V-shaped surface corresponds to the groove position of the V-shaped surface of each terminal. The setting of the V-shaped surface can further control the flashover stability performance.

Both ends are perpendicular to the central electrode. The two terminals can also be perpendicular to the central electrode, and in this case the terminals can be L-shaped.

The insulator is provided with a first passage through the insulator, the first passage is located on the side of the central electrode, and is separated from the central electrode by the insulating material of the insulator and does not intersect, and a conductive tube is connected above the first channel, and the conductive tube is used In order to communicate with the intake manifold of the engine, the conduction pipe is also connected with a gas booster device, and an auxiliary intake valve is arranged at the bottom of the first channel. The auxiliary intake valve is connected with the intake valve structure of the engine, and the auxiliary intake valve follows the intake valve structure of the intake valve structure for switch movement. In order to make the auxiliary intake valve and the intake valve structure easy to connect, the first channel It is arranged in a straight line instead of a broken line, and the valve part and the spring part of the auxiliary intake valve are arranged in such a way that the valve part is arranged in the first passage and extends out of the first passage opening, the valve part is made of insulating material, and the spring part is arranged in the The outside of the first channel, and the spring part is also made of insulating material. Therefore, the auxiliary intake valve is different from the ordinary intake valve. The valve connecting rod of the auxiliary intake valve is longer than that of the ordinary intake valve and longer than the long diameter of the first channel. The bell mouth of the auxiliary intake valve is longer than that of the ordinary intake valve. The small size of the intake valve and matching the diameter of the outlet of the first passage can block the outlet of the first passage. After the ordinary spark plug has been used for a period of time, the reason for the unstable flashover is that the gap between the central electrode and the ground electrode has changed. The amount of combustion gas existing in the gap is small and the combustion is insufficient, so the flashover is unstable and easy to extinguish. In the present invention, by integrating a first passage communicated with the intake manifold in the insulator of the spark plug, sufficient combustion gas can be obtained when the engine takes in air, thus enabling quick flashover and improving the ignition performance of the spark plug. The gas pressurization device is used to pressurize the gas entering the first channel to increase the flow rate of the gas. On the one hand, it can improve the fluidity of the mixed gas, provide more mixed gas for the gap, and prevent the gap between the central electrode and the ground electrode. The gas is in a static state for a long time without enough mixed gas to fill in, making it difficult to flash over. On the other hand, the fresh gas flowing in can reduce the temperature of the spark plug at high temperature and improve the service life of the spark plug. In addition, the flow rate of the gas surge can also Take away the carbon deposits generated on the spark plug electrodes, and also contribute to improving the service life of the spark plugs. Setting the auxiliary intake valve can realize that when the cylinder inhales air, the gas passes through the air filter and then enters the intake manifold, and then reaches the first channel. When the gas in the cylinder needs to deflagrate, the mixed gas generated by the explosion will not It will enter into the first passage, so that the gas pressure obtained by the cylinder will not be lost, which will affect the engine performance.

At least one end face of each terminal and the end face of at least one grounding electrode are coated with an alloy sheet layer.

The alloy sheets contain iridium, platinum, nickel and copper.

The alloy sheet layer contains platinum as main components, iridium at 5-15wt%, copper at 6-20wt%, and nickel at 5-10wt%. In the present invention, since the main component of the alloy sheet layer coated on the end face of the electrode is platinum, plus iridium, copper, and nickel of limited composition, it can resist high temperature, oxidation and ablation. In order to allow enough air to be filled between the central electrode and the ground electrode, the alloy sheet structure of the central electrode and the ground electrode is porous and loose. The specific method is to combine the metal powder and the porous carrier at high temperature and extend it into The sheet is welded to the electrode. In addition, the ratio of the metal components in the alloy sheet layer in the present invention can take both economic cost and heat dissipation performance into consideration. The porous carrier is a honeycomb sheet-shaped porous carrier, and the porous and loose alloy sheet can be set into a sheet structure with multiple dense micropores, and the dense micropores are arranged in a wave shape on the honeycomb sheet-shaped porous alloy sheet. The diameter of the pores is 50-100 microns. The high temperature is 900-1500°C. The setting of the honeycomb sheet-like porous and dense small holes can make the airflow filled between the central electrode and the ground electrode flow in series, so that the contact time between the air and the electrodes becomes longer.

A method for prolonging the service life of the spark plug of a horizontally opposed engine. The aforementioned spark plugs are placed in the positions corresponding to the spark plugs of the four cylinders of the horizontally opposed engine. After 50 hours of use, the upper spark plug and the lower spark plug of the first cylinder are removed. After marking, clean, adjust the gap, polish and polish after testing, and exchange positions; the remaining second, third, and fourth cylinders all use the above method to exchange the positions of the upper spark plug and the lower spark plug. The cleaning process is to use spark plug vibration cleaning The oil, carbon and lead deposits are removed by the device, and the gap adjustment is to adjust the gap between the positive and negative electrodes of the spark plug. The principle of use is to exchange the positions of the upper spark plug and the lower spark plug, and the exchange can be same-cylinder exchange, opposite exchange, or same-side exchange.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The invention can improve the anti-oxidation performance, improve the corrosion resistance of the electrode at high temperature, and prolong the service life of the spark plug;

2. The present invention can also provide sufficient mixed gas for the gap between the central electrode and the ground electrode, making flashover easier and more stable, and can also reduce the working temperature of the spark plug and take away the carbon deposit on the spark plug electrode;

3. The present invention can form a uniform spark between the central electrode and the ground electrode, and the relative arrangement of the ground electrode and each end of the central electrode can reduce the flame-extinguishing effect of the ground electrode and improve the flashover stability of the spark plug;

4. The present invention arranges the first channel in the insulator, which can simplify the structure of the spark plug, reduce the occupied space of the spark plug inside the engine, and reduce the manufacturing cost of the engine.

Description of drawings

The drawings described here are used to provide a further understanding of the embodiments of the present invention, constitute a part of the application, and do not limit the embodiments of the present invention. In the attached picture:

Fig. 1 is a schematic diagram of the structure of the present invention.

Marks and corresponding parts names in the attached drawings:

1-central electrode, 2-metal shell, 3-ground electrode, 4-first channel, 51-valve, 52-valve connecting rod, 53-spring part.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the examples and accompanying drawings. As a limitation of the present invention.

Example 1

As shown in Figure 1, a spark plug includes a central electrode 1 and an insulator, the central electrode 1 is arranged inside the insulator and extends out of the insulator along its axial direction, the lower end of the insulator is covered with a metal shell 2, The lower end of the metal shell 2 is a threaded structure, and the lower end of the metal shell 2 is connected with a ground electrode 3, the ground electrode 3 is L-shaped, there is a gap between the ground electrode 3 and the central electrode 1, and the discharge electrode of the central electrode 1 is split into two ends, the two ends are evenly distributed on the discharge electrode of the central electrode 1, the end face of each end is a slope, the number of ground electrodes 3 is equal to the number of ends, and each ground electrode 3 and each The positions of the two terminals are opposite, and the end surface of each ground electrode 3 is also an inclined plane and is parallel to the end surface of each terminal with a gap.

The number of corresponding ground electrodes 3 is opposite to the number of terminals. The distances between the individual gaps are equal.

Example 2

The end face of each end is a V-shaped face.

The end surface of each ground electrode 3 is a V-shaped surface, and the groove positions of the V-shaped surface correspond to the groove positions of the V-shaped surface of each end.

Example 3

As shown in FIG. 1 , at least two ends are perpendicular to the central electrode 1 .

The insulator is provided with a first channel 4 that runs through the insulator. The first channel 4 is located on the side of the central electrode 1 and is separated from the central electrode 1 by the insulating material of the insulator. A conductive tube is also connected above the first channel 4. The conduction pipe is used to communicate with the intake manifold of the engine, and the conduction pipe is also connected with a gas booster device, and an auxiliary intake valve is arranged at the bottom of the first channel 4 .

The auxiliary intake valve is connected with the intake valve structure of the engine, and the auxiliary intake valve follows the intake valve structure of the intake valve structure for switch movement. In order to make the auxiliary intake valve and the intake valve structure easy to connect, the first channel 4. It is arranged in a straight line instead of a broken line, and the valve part and spring part 53 of the auxiliary intake valve are set in such a way that the valve part is arranged in the first channel and extends out of the first channel opening, the valve part is made of insulating material, and the spring part 53 is arranged outside the first channel, and the spring part is also made of insulating material. Therefore, the auxiliary intake valve is different from the common intake valve. The valve connecting rod 52 of the auxiliary intake valve is longer than that of the common intake valve and longer than the long diameter of the first channel. The horn of the valve 51 of the auxiliary intake valve is The port is smaller than that of a common intake valve and matches the diameter of the first passage outlet to block the first passage outlet 4 .

After the ordinary spark plug has been used for a period of time, the reason for the unstable flashover is that the gap between the central electrode 1 and the ground electrode 3 has changed, the amount of combustion gas existing in the gap is small, and the combustion is insufficient, so the flashover is unstable and easy to extinguish . In the present invention, by integrating a first channel 4 connected with the intake manifold in the insulator of the spark plug, sufficient combustion gas can be obtained when the engine is taking in air, thereby enabling rapid flashover and improving the ignition performance of the spark plug.

Example 4

At least one end surface of each terminal and the end surface of at least one ground electrode 3 are coated with an alloy sheet layer.

The alloy sheets contain iridium, platinum, nickel and copper.

The alloy sheet layer contains platinum as main components, iridium at 5-15wt%, copper at 6-20wt%, and nickel at 5-10wt%. In the present invention, since the main component of the alloy sheet layer coated on the end face of the electrode is platinum, it can resist high temperature, oxidation and ablation. In order to allow enough air to be filled between the central electrode 1 and the ground electrode 3, the alloy sheet structure of the central electrode 1 and the ground electrode 3 is porous and loose. The specific method is to combine the metal and the porous carrier at high temperature, and It is extended in sheets and welded to the electrodes. In addition, the ratio of the metal components in the alloy sheet layer in the present invention can take both economic cost and heat dissipation performance into consideration.

The porous carrier is a honeycomb sheet-shaped porous carrier, and the porous and loose alloy sheet can be set into a sheet structure with multiple dense micropores, and the dense micropores are arranged in a wave shape on the honeycomb sheet-shaped porous alloy sheet. The diameter of the pores is 50-100 microns. The high temperature is 900-1500°C. The setting of the honeycomb sheet-like porous and dense small holes can make the airflow filled between the central electrode and the ground electrode flow in series, so that the contact time between the air and the electrodes becomes longer.

Example 5

A method for prolonging the service life of the spark plug of a horizontally opposed engine. The aforementioned spark plugs are placed in the positions corresponding to the spark plugs of the four cylinders of the horizontally opposed engine. After 50 hours of use, the upper spark plug and the lower spark plug of the first cylinder are removed. After marking, clean, adjust the gap, polish and polish after testing, and exchange positions; the remaining second, third, and fourth cylinders all use the above method to exchange the positions of the upper spark plug and the lower spark plug. The cleaning process is to use spark plug vibration cleaning The oil, carbon and lead deposits are removed by the device, and the gap adjustment is to adjust the gap between the positive and negative electrodes of the spark plug. The principle of use is to exchange the positions of the upper spark plug and the lower spark plug, and the exchange can be same-cylinder exchange, opposite exchange, or same-side exchange.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the scope of the present invention. Protection scope, within the spirit and principles of the present invention, any modification, equivalent replacement, improvement, etc., shall be included in the protection scope of the present invention.

Claims (8)

1. A spark plug, comprising a central electrode (1) and an insulator, the central electrode (1) is arranged inside the insulator and extends out of the insulator along its axial direction, and the lower end of the insulator is covered with a metal shell (2 ), the lower end of the metal shell (2) is a threaded structure, and the lower end of the metal shell (2) is connected to the ground electrode (3), and there is a gap between the ground electrode (3) and the central electrode (1), which is characterized in that , the discharge electrode of the central electrode (1) is bifurcated into 2 ends, and the 2 ends are evenly distributed on the discharge electrode of the central electrode (1), the end face of each end is a slope, the number of ground electrodes (3) The number is equal to the number of terminals, and each ground electrode (3) is opposite to each terminal, and the end surface of each ground electrode (3) is also inclined and parallel to the end surface of each terminal with a gap, 2 Both ends are perpendicular to the central electrode (1), the insulator is provided with a first channel (4) passing through the insulator, the first channel (4) is located on the side of the central electrode (1), and the central electrode (1) passes through the insulator The insulation materials are separated and do not intersect each other. A conduction pipe is connected above the first channel (4), and the conduction pipe is used to communicate with the intake manifold of the engine. The conduction pipe is also connected with a gas booster device. An auxiliary intake valve is also arranged at the bottom of the first channel (4). 2. The spark plug according to claim 1, characterized in that, the end surface of each terminal is a V-shaped surface, the end surface of each ground electrode (3) is a V-shaped surface, and the groove position of the V-shaped surface and each The position of the groove on the V-shaped surface of the end corresponds to that. 3. The spark plug according to claim 1, characterized in that, the lower end of the first channel (4) is opposite to the gap between the central electrode (1) and the ground electrode (3). 4. The spark plug according to claim 1, characterized in that, at least one end surface of each terminal and the end surface of at least one ground electrode (3) are coated with an alloy sheet layer. 5. The spark plug according to claim 4, wherein said alloy sheet contains iridium, platinum, nickel and copper. 6. The spark plug according to claim 5, characterized in that, the alloy sheets contain platinum as the main components, iridium of 5-15wt%, copper of 6-20wt%, and nickel of 5-10wt%. 7. The spark plug according to claim 6, characterized in that, the alloy flakes are made of powdered main components of platinum, 5-15wt% iridium, 6-20wt% copper, 5-10wt% nickel Dispersion bonding of porous support alloy sheets obtained on a porous support. 8. A method for prolonging the service life of a horizontally opposed engine spark plug, characterized in that the spark plug according to any one of claims 1-7 is placed on the corresponding spark plug placement positions of the four cylinders of the horizontally opposed engine, and after 50 hours of use , Remove the upper and lower spark plugs of the first cylinder, clean them after marking, adjust the gap, polish and polish after testing, and exchange positions; the remaining second, third, and fourth cylinders all use the above method to replace the upper spark plugs and lower spark plugs. Spark plug positions swapped.