Spark plug, engine and vehicle

Abstract

The present application relates to the technical field of engines, and specifically to a spark plug, an engine and a vehicle. The spark plug comprises a pre-combustion chamber cap; and a jet hole structure, which penetrates the pre-combustion chamber cap, and comprises a first jet tube and a second jet tube, which are in communication with each other, wherein a first opening of the first jet tube is located in an inner wall of the pre-combustion chamber cap; a second opening of the second jet tube is located in an outer wall of the pre-combustion chamber cap; and the diameter of the first jet tube is different from that of the second jet tube. By means of the above technical solution, carbon deposits are concentrated around an outlet of the second jet tube of the spark plug, thereby effectively preventing the carbon deposits from accumulating to the first jet tube on the inner side, and reducing the effect of the carbon deposits on the primary development of a jet flame; furthermore, an outlet of the first jet tube and an internal flow channel of the jet hole structure of a pre-combustion chamber are also protected, such that the propagation of the jet flame inside a jet hole is not affected.

Description

Spark plug, engine and vehicle

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 18, 2024, with application number 202420294048.7 and application name “A Spark Plug, Engine and Vehicle”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of engine technology, and in particular to a spark plug, an engine and a vehicle. Background Art

[0003] In some vehicle models, the pre-combustion chamber nozzle, which works in a high-temperature and low-temperature rapid switching environment for a long time, is prone to carbon deposits. Carbon deposits will reduce the flow area of ​​the nozzle and, in severe cases, will cause the pre-combustion chamber ignition system to fail. Therefore, seeking a nozzle structure that reduces carbon deposits is a technical problem that needs to be solved urgently.

[0004] Summary of the Invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the first object of the present application is to provide a spark plug that prevents carbon deposits from accumulating in the inner first nozzle, thereby reducing the impact of carbon deposits on the primary development of the jet flame and preventing the jet flame from affecting its propagation within the nozzle orifice.

[0006] The second object of the present application is to provide an engine. The third object of the present application is to provide a vehicle.

[0007] In order to solve the above problems, the first embodiment of the present application provides a spark plug, including: a pre-combustion chamber cap; a nozzle structure, the nozzle structure passes through the pre-combustion chamber cap, the nozzle structure includes a first nozzle and a second nozzle that are connected, the first opening of the first nozzle is located on the inner wall of the pre-combustion chamber cap, and the second opening of the second nozzle is located on the outer wall of the pre-combustion chamber cap, and the diameter of the first nozzle is different from the diameter of the second nozzle.

[0008] In some embodiments, the tilt angle between the axis of the nozzle structure and the axis of the pre-combustion chamber cap is α, 0≤α≤70°.

[0009] In some embodiments, the diameter of the first nozzle is smaller than the diameter of the second nozzle.

[0010] In some embodiments, the length of the first nozzle is L1, the length of the second nozzle is L2, and 1.2≤L2 / L1≤1.8.

[0011] In some embodiments, the diameter of the first nozzle is d1, 0.08≤d1≤0.35 mm, and the diameter of the second nozzle is d2, 0.08≤d2≤0.35 mm, wherein d1<d2.

[0012] In some embodiments, a diameter ratio of the second nozzle to the first nozzle is d2 / d1, and 1.2≤d2 / d1≤1.8.

[0013] In some embodiments, the diameter of the first nozzle is greater than the diameter of the second nozzle.

[0014] In some embodiments, the length of the first nozzle is L1, the length of the second nozzle is L2, and 1.2≤L1 / L2≤1.8.

[0015] In some embodiments, the diameter of the first nozzle is d1, 0.08≤d1≤0.35 mm, and the diameter of the second nozzle is d2, 0.08≤d2≤0.35 mm, wherein d1>d2.

[0016] In some embodiments, a diameter ratio of the first nozzle and the second nozzle is d1 / d2, and 1.2≤d1 / d2≤1.8.

[0017] A second aspect of the present application provides an engine comprising the above-mentioned spark plug.

[0018] A third aspect of the present application provides a vehicle comprising the above-mentioned engine.

[0019] The diameter of the first nozzle of the nozzle structure of the present application is different from the diameter of the second nozzle. Therefore, the first nozzle and the second nozzle are stepped, and the stepped nozzle structure forms a gradually expanding tube structure. This structure has the characteristics of low flow resistance, so that carbon deposits are concentrated around the outlet of the second nozzle of the spark plug, effectively avoiding the accumulation of carbon deposits on the inner first nozzle, thereby reducing the impact of carbon deposits on the primary development of the jet flame. In addition, it also protects the first nozzle outlet of the pre-combustion chamber and the internal flow channel of the nozzle structure, so as not to affect the propagation of the jet flame inside the nozzle.

[0020] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present application but do not constitute a limitation of the present application.

[0022] FIG1 is a schematic cross-sectional view of a spark plug according to a first embodiment of the present application;

[0023] FIG2 is a schematic cross-sectional view of a pre-combustion chamber cap according to a first embodiment of the present application;

[0024] FIG3 is a schematic cross-sectional view of a spark plug according to a second embodiment of the present application;

[0025] FIG4 is a schematic cross-sectional view of a pre-combustion chamber cap according to a second embodiment of the present application;

[0026] FIG5 is a schematic diagram showing the change in effective diameter of three different nozzle hole structures as mileage increases;

[0027] FIG6 is an experimental carbon deposition diagram of the first embodiment of the present application.

[0028] Description of reference numerals:

[0029] Precombustion chamber cap: 1; nozzle hole structure: 2; first nozzle: 21; first opening: 211; second nozzle: 22; second opening: 221; axis of the nozzle hole structure: 23; axis of the precombustion chamber cap: 24. DETAILED DESCRIPTION

[0030] The following describes the specific embodiments of the present application in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application.

[0031] In this application, unless otherwise specified, the terms "inside" and "outside" refer to the "inside" and "outside" relative to the outline of the corresponding component itself, and "far" and "near" refer to the "far" and "near" compared to the reference object. In addition, the terms used in this application, such as "first" and "second", are used to distinguish one element from another and do not have order or importance. In the following description, when referring to the drawings, unless otherwise explained, the same figure numbers in different drawings represent the same or similar elements. The above definitions are only used to explain and illustrate this application and should not be understood as limiting this application.

[0032] 1-2 , the present application discloses a first embodiment of a spark plug.

[0033] Referring to Figure 1, in this embodiment, a spark plug includes a pre-combustion chamber cap 1 and a nozzle structure 2, the nozzle structure 2 passes through the pre-combustion chamber cap 1, and the nozzle structure 2 includes a first nozzle 21 and a second nozzle 22 that are connected. The first opening 211 of the first nozzle 21 is located on the inner wall of the pre-combustion chamber cap 1, and the second opening 221 of the second nozzle 22 is located on the outer wall of the pre-combustion chamber cap 1. The diameter of the first nozzle 21 is different from the diameter of the second nozzle 22.

[0034] In this embodiment, the spray hole structure 2 passes through the pre-combustion chamber cap 1. It should be explained in detail that the spray hole structures 2 are evenly distributed on the pre-combustion chamber cap 1, and the number of the spray hole structures 2 can be 4 or 8.

[0035] In this embodiment, the diameter of the first nozzle 21 of the nozzle structure 2 is different from the diameter of the second nozzle 22. Therefore, the first nozzle 21 and the second nozzle 22 are stepped. The stepped nozzle structure 2 forms a gradually expanding tube structure, which has the characteristics of low flow resistance, so that carbon deposits are concentrated around the outlet of the second nozzle 22 of the spark plug, effectively avoiding the accumulation of carbon deposits on the inner first nozzle 21, thereby reducing the impact of carbon deposits on the primary development of the jet flame. In addition, it also protects the outlet of the first nozzle 21 of the pre-combustion chamber and the internal flow channel of the nozzle structure 2, thereby not affecting the propagation of the jet flame inside the nozzle.

[0036] 2 , the inclination angle between the axis 23 of the nozzle structure and the axis 24 of the pre-combustion chamber cap is α, 0≤α≤70°.

[0037] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having d1 = 0.15 mm, L1 = 0.32 mm, d2 = 0.24 mm, and L2 = 0.44 mm is selected as the experimental object. The experimental data are shown in the following table:

[0038] As can be seen from the above table, in this embodiment, when the tilt elevation angle is set in the range of 0≤α≤70°, the ignition delay period is between 10.1-12.1 degrees, which is less than the optimal ignition delay period of 12.2 degrees when the tilt elevation angle is set at >70°. Therefore, when the tilt elevation angle is set in the range of 0≤α≤70°, the combustion performance is better.

[0039] In addition, in this embodiment, when the tilt angle is set in the range of 0≤α≤70°, the combustion duration is between 23.3-25.2deg, which is less than the optimal combustion duration of 26.3deg when the tilt angle is set at >70°. Therefore, when the tilt angle is set in the range of 0≤α≤70°, the combustion performance is better.

[0040] Referring to FIG. 1 , in this embodiment, the diameter of the first nozzle 21 is smaller than the diameter of the second nozzle 22 .

[0041] In this embodiment, the length of the first nozzle is L1, the length of the second nozzle is L2, and 1.2≤L2 / L1≤1.8.

[0042] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having d1 = 0.15 mm, d2 = 0.24 mm, and α = 60° is selected as the experimental object. The experimental data are shown in the following table:

[0043] As can be seen from the above table, in this embodiment, when L2 / L1 is set in the range of 1.2≤L2 / L1≤1.8, the ignition delay period is between 11.9-12.4 degrees, both of which are smaller than the optimal ignition delay periods of 12.7 and 12.9 degrees when L2 / L1 is set at L2 / L1<1.2 and L2 / L1>1.8. Therefore, when L2 / L1 is set in the range of 1.2≤L2 / L1≤1.8, the combustion performance is better.

[0044] In addition, in this embodiment, when L2 / L1 is set in the range of 1.2≤L2 / L1≤1.8, the combustion duration is between 24.3-26.4deg, which are both smaller than the optimal combustion durations of 26.9deg and 26.6deg when L2 / L1 is set at L2 / L1<1.2 and L2 / L1>1.8. Therefore, when L2 / L1 is set in the range of 1.2≤L2 / L1≤1.8, the combustion performance is better.

[0045] 2 , in this embodiment, the diameter of the first nozzle 21 is d1, 0.08≤d1≤0.35 mm, and the diameter of the second nozzle 22 is d2, 0.08≤d2≤0.35 mm, wherein d1<d2.

[0046] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having L1 = 0.32 mm, L2 = 0.44 mm, d2 = 0.35 mm, and α = 60° is selected as the experimental object. The experimental data are shown in the following table:

[0047] As can be seen from the above table, in this embodiment, when d1 is set in the range of 0.08≤d1≤0.35mm, the ignition delay period is between 11.3-13.2deg, which is smaller than the optimal ignition delay period of 13.9deg when d1 is set in d1<0.08. Therefore, when d1 is set in the range of 0.08≤d1≤0.35mm, the combustion performance is better.

[0048] In addition, in this embodiment, when d1 is set in the range of 0.08≤d1≤0.35mm, the combustion duration is between 23.5.3-30.5deg, which is less than the optimal combustion duration of 32.3deg when d1 is set in d1<0.08. Therefore, when d1 is set in the range of 0.08≤d1≤0.35mm, the combustion performance is better.

[0049] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having L1 = 0.32 mm, L2 = 0.44 mm, d1 = 0.08 mm, and α = 60° is selected as the experimental object. The experimental data are shown in the following table:

[0050] As can be seen from the above table, in this embodiment, when d2 is set in the range of 0.08≤d2≤0.35mm, the ignition delay period is between 13.9-15.5deg, which is smaller than the optimal ignition delay period of 15.7deg when d2 is set in the range of d2>0.35. Therefore, when d2 is set in the range of 0.08≤d2≤0.35mm, the combustion performance is better.

[0051] In addition, in this embodiment, when d2 is set in the range of 0.08≤d2≤0.35mm, the combustion duration is between 24.8-27.2deg, which is less than the optimal combustion duration of 28.6deg when d2 is set in d2>0.35. Therefore, when d2 is set in the range of 0.08≤d2≤0.35mm, the combustion performance is better.

[0052] In this embodiment, the diameter ratio of the second nozzle 22 to the first nozzle 21 is d2 / d1, and 1.2≤d2 / d1≤1.8.

[0053] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having L1 = 0.32 mm, L2 = 0.44 mm, and α = 60° is selected as the experimental object. The experimental data are as follows:

[0054] As can be seen from the above table, in this embodiment, when d2 / d1 is set in the range of 1.2≤d2 / d1≤1.8, the ignition delay period is between 11.5-15.2 degrees, which are both smaller than the optimal ignition delay periods of 17.1 and 15.6 degrees when d2 is set at d2 / d1<1.2h and d2 / d1>1.8. Therefore, when d2 / d1 is set in the range of 1.2≤d2 / d1≤1.8, the combustion performance is better.

[0055] In addition, in this embodiment, when d2 / d1 is set in the range of 1.2≤d2 / d1≤1.8, the combustion duration is between 23.6-28.9deg, which are both smaller than the optimal combustion durations of 29.5 and 32deg when d2 / d1 is set at d2 / d1<1.2h and d2 / d1>1.8. Therefore, when d2 / d1 is set in the range of 1.2≤d2 / d1≤1.8, the combustion performance is better.

[0056] 3 and 4 , the present application discloses a second embodiment of the spark plug. Compared with the first embodiment, the second embodiment is different in that the diameter of the first nozzle 21 is greater than the diameter of the second nozzle 22 .

[0057] 3 , in this embodiment, the diameter of the first nozzle 21 is greater than the diameter of the second nozzle 22 .

[0058] 4 , in this embodiment, the length of the first nozzle is L1 , the length of the second nozzle is L2 , and 1.2≤L1 / L2≤1.8.

[0059] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having d1 = 0.24 mm, d2 = 0.15 mm, and α = 60° is selected as the experimental object. The experimental data are shown in the following table:

[0060] As can be seen from the above table, in this embodiment, when L1 / L2 is set in the range of 1.2≤L2 / L1≤1.8, the ignition delay period is between 17.5-18.3 degrees, both of which are smaller than the optimal ignition delay periods of 18.6 and 19.2 degrees when L1 / L2 is set at L1 / L2<1.2 and L1 / L2>1.8. Therefore, when L1 / L2 is set in the range of 1.2≤L2 / L1≤1.8, the combustion performance is better.

[0061] In addition, in this embodiment, when L1 / L2 is set in the range of 1.2≤L2 / L1≤1.8, the combustion duration is between 32.3-34.6 degrees, which is less than the optimal combustion duration of 37.2 and 35.1 degrees when L1 / L2 is set at L1 / L2 < 1.2 and L1 / L2 > 1.8. Therefore, when L1 / L2 is set in the range of 1.2≤L2 / L1≤1.8, the combustion performance is better. In this embodiment, a pre-combustion chamber with a nozzle structure 2 having L1 = 0.44 mm, L2 = 0.32 mm, d2 = 0.08 mm, and α = 60° is selected as the experimental object, and the experimental data are as follows:

[0062] As can be seen from the above table, in this embodiment, when d1 is set in the range of 0.08≤d1≤0.35mm, the ignition delay period is between 19.6-21.3deg, which is less than the optimal ignition delay period of 21.5deg when d1 is set in d1>0.35. Therefore, when d1 is set in the range of 0.08≤d1≤0.35mm, the combustion performance is better.

[0063] In addition, in this embodiment, when d1 is set in the range of 0.08≤d1≤0.35mm, the combustion duration is between 32.5-34.9deg, which is smaller than the optimal combustion duration of 35.2deg when d1 is set in d1>0.35. Therefore, when d1 is set in the range of 0.08≤d1≤0.35mm, the combustion performance is better.

[0064] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having L1 = 0.44 mm, L2 = 0.32 mm, d2 = 0.08 mm, and α = 60° is selected as the experimental object. The experimental data are shown in the following table:

[0065] As can be seen from the above table, in this embodiment, when d2 is set in the range of 0.08≤d2≤0.35mm, the ignition delay period is between 20.8-24.8deg, which is less than the optimal ignition delay period of 25.3deg when d2 is set in the range of d2<0.08. Therefore, when d2 is set in the range of 0.08≤d2≤0.35mm, the combustion performance is better.

[0066] In addition, in this embodiment, when d2 is set in the range of 0.08≤d2≤0.35mm, the combustion duration is between 33.9-37.6deg, which is less than the optimal combustion duration of 38.1deg when d2 is set in d2<0.08. Therefore, when d2 is set in the range of 0.08≤d2≤0.35mm, the combustion performance is better.

[0067] In this embodiment, the diameter ratio of the first nozzle and the second nozzle is d1 / d2, and 1.2≤d1 / d2≤1.8.

[0068] In this embodiment, a pre-combustion chamber with a nozzle hole structure 2 having L1 = 0.44 mm, L2 = 0.32 mm, and α = 60° is selected as the experimental object. The experimental data are shown in the following table:

[0069] As can be seen from the above table, in this embodiment, when d1 / d2 is set in the range of 1.2≤d2 / d1≤1.8, the ignition delay period is between 23.1-24.9 degrees, which are both smaller than the optimal ignition delay periods of 27.1 and 25.1 degrees when d1 / d2 is set at d1 / d2<1.2h and d1 / d2>1.8. Therefore, when d1 / d2 is set in the range of 1.2≤d1 / d2≤1.8, the combustion performance is better.

[0070] Furthermore, in this embodiment, when d1 / d2 is set in the range of 1.2≤d1 / d2≤1.8, the combustion duration is between 35.2-36.1 degrees, both of which are less than the optimal combustion durations of 38.9 and 36.4 degrees when d1 / d2 is set in the range of d1 / d2 < 1.2h and d1 / d2 > 1.8, respectively. Therefore, when d1 / d2 is set in the range of 1.2≤d1 / d2≤1.8, the combustion performance is better. Referring to Figure 5, to more intuitively compare the effectiveness of conventional nozzle designs with the first and second embodiments of this application in preventing carbon deposits, the effective diameters of the three nozzle structures under different usage conditions were measured through a blowing test, and the data were normalized using the initial diameter to ensure comparability.

[0071] Mileage reflects usage. As mileage increases, the effective diameter of the nozzle holes for all three pre-combustion chambers gradually decreases. This is because as carbon deposits increase, the flow area decreases, and the air flow rate under a constant pressure differential also decreases, resulting in a decrease in the effective diameter calculated from the flow rate. It's easy to see that the effective diameter of the pre-combustion chamber with a stepped nozzle design decreases more slowly than that of a conventional straight-tube nozzle pre-combustion chamber. This means that the first and second embodiments can effectively extend their service life while maintaining the same quality standards.

[0072] Referring to Figure 6, the pre-combustion chamber spark plug system of the first embodiment was installed on a common four-cylinder direct-injection supercharged engine. After a 50,000-kilometer endurance test, the pre-combustion chamber was removed and the carbon deposits inside the nozzle orifice were observed using an electron microscope. To clearly visualize the internal structure of the nozzle orifice, the nozzle was cut open. A load-bearing machine was then used to apply pressure to the center axis of the nozzle orifice until it collapsed. Once the pressure had collapsed, the carbon deposits inside the orifice could be observed.

[0073] Electron microscopic examination of the nozzle surface revealed only a small amount of carbon deposits on the first nozzle 21 connected to the pre-combustion chamber, while the second nozzle 22 connected to the main combustion chamber had more carbon deposits. Most of the carbon deposits were concentrated on the outer surface of the second nozzle 22, consistent with the mechanism of carbon deposit formation. This indicates that the stepped nozzle effectively prevents carbon deposits from accumulating inwardly on the first nozzle 21, thereby reducing their impact on the primary development of the jet flame.

[0074] The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings. However, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, various simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the scope of protection of the present application.

[0075] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner unless there is any contradiction. In order to avoid unnecessary repetition, this application will not further describe various possible combinations.

[0076] In addition, the various implementation methods of the present application can also be arbitrarily combined, as long as they do not violate the concept of the present application, they should also be regarded as the content applied for in the present application.

Claims

1. A spark plug, wherein: include: pre-chamber cap; A spray hole structure, wherein the spray hole structure passes through the pre-combustion chamber cap, and the spray hole structure includes a first nozzle and a second nozzle that are connected, wherein the first opening of the first nozzle is located on the inner wall of the pre-combustion chamber cap, and the second opening of the second nozzle is located on the outer wall of the pre-combustion chamber cap, and the diameter of the first nozzle is different from the diameter of the second nozzle.

2. The spark plug according to claim 1, wherein The inclination angle between the axis of the nozzle structure and the axis of the pre-combustion chamber cap is α, 0≤α≤70°.

3. The spark plug according to claim 1 or 2, wherein: The diameter of the first nozzle is smaller than the diameter of the second nozzle.

4. The spark plug according to claim 3, wherein: The length of the first nozzle is L1, the length of the second nozzle is L2, and 1.2≤L2 / L1≤1.

8.

5. The spark plug according to claim 3, wherein The diameter of the first nozzle is d1, 0.08≤d1≤0.35 mm, and the diameter of the second nozzle is d2, 0.08≤d2≤0.35 mm, wherein d1<d2.

6. The spark plug according to claim 5, wherein A diameter ratio of the second nozzle to the first nozzle is d2 / d1, and 1.2≤d2 / d1≤1.

8.

7. The spark plug according to claim 1 or 2, wherein: The diameter of the first nozzle is greater than the diameter of the second nozzle.

8. The spark plug according to claim 7, wherein The length of the first nozzle is L1, the length of the second nozzle is L2, and 1.2≤L1 / L2≤1.

8.

9. The spark plug according to claim 7, wherein: The diameter of the first nozzle is d1, 0.08≤d1≤0.35 mm, and the diameter of the second nozzle is d2, 0.08≤d2≤0.35 mm, wherein d1>d2.

10. The spark plug according to claim 9, wherein The diameter ratio of the first nozzle and the second nozzle is d1 / d2, and 1.2≤d1 / d2≤1.

8.

11. An engine, wherein: The engine comprises the spark plug according to any one of claims 1 to 10.

12. A vehicle, wherein: The vehicle includes the engine of claim 11.

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