Self-rotating oil nozzle matching part and oil sprayer

Abstract

A limiting ring is arranged in a gap between the outer wall of a needle valve and the inner wall of an oil spraying nozzle and used for limiting upward movement of a spraying hole rotating part. The end, close to the needle valve, of the spray hole rotating piece is provided with a flange extending in the circumferential direction of the outer wall. Protruding guide ribs are arranged on the outer wall of the flange. A plurality of spraying holes penetrating through the side wall of the spraying hole rotating part are formed in the side wall of the spraying hole rotating part and used for spraying oil into the engine; a groove is formed in the inner wall of the oil nozzle and used for containing the sealing assembly, and the sealing assembly has elastic potential energy. The lower edge of the flange of the spray hole rotating piece makes contact with the upper edge of the sealing assembly, and the bottom of the flange of the spray hole rotating piece can press or release the sealing assembly when the spray hole rotating piece does spiral motion along a guide groove in the inner wall of the oil spray nozzle.

Description

Technical Field

[0001] The present invention relates to the field of engines, in particular to a self-rotating oil nozzle pair and a fuel injector having the self-rotating oil nozzle pair. Background Art

[0002] As a primary power source in the transportation sector, diesel engine performance directly impacts productivity and quality. To improve fuel atomization, evaporation, and mixing uniformity, while also reducing emissions, existing fuel injectors typically utilize high injection pressures and small nozzle diameters. However, excessively high injection pressures place higher demands on the manufacturing of precision injector couplings. Therefore, improvements to the injector nozzle structure are needed to optimize spray performance and combustion.

[0003] Conventional fuel injectors typically feature several circular nozzles. The location, angle, and number of these nozzles alter the injector's internal flow path. However, as demand for engines shifts toward lighter weight and higher power density, the amount of fuel injected per shot increases, leading to higher injection pressures. This increases the spray penetration distance, which in some small engines poses a risk of wall impact. Consequently, there is a need to strengthen the radial direction of the spray.

[0004] Patent CN103397964B discloses a centrifugal umbrella atomizer, which provides a new fuel atomization method, structure, and function for HCCI combustion in internal combustion engines. The fuel with tangential force rotates tangentially in the swirl chamber and is ejected from the nozzle, forming a hollow umbrella-shaped oil film in the combustion chamber with no dense oil beam core, controllable penetration distance, and high-speed rotation. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention provides a self-rotating nozzle assembly and fuel injector. The nozzle assembly incorporates a sealing assembly within a groove in a third space formed between the nozzle and a rotating nozzle member. During fuel injection, the rotating nozzle member compresses the sealing assembly, allowing the nozzle to automatically rotate and inject fuel, relying on the injection pressure within the injector's internal flow channel.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A first aspect of the present invention is to provide a self-spinning oil nozzle assembly, comprising an oil nozzle, wherein the inner wall of the oil nozzle accommodates a portion of a needle valve, a spray hole rotating member and a sealing assembly;

[0008] A limiting ring is provided in the gap between the outer wall of the needle valve and the inner wall of the fuel injection nozzle, is fixed relative to the fuel injection nozzle, and can limit the upward movement of the nozzle rotating part;

[0009] The spray hole rotating member, the needle valve, and the limiting ring are coaxially arranged in the fuel injector, and the end of the spray hole rotating member near the needle valve has a flange extending circumferentially along its outer wall; the outer wall of the flange has a protruding guide rib; a plurality of spray holes are formed on the side wall of the spray hole rotating member and pass through the side wall of the spray hole rotating member, and the spray holes are inclined holes. The position of the spray holes on the outer wall of the spray hole rotating member is lower than the fourth space of the fuel injector, so that the spray holes can be kept away from the fuel injector during the movement of the spray hole rotating member.

[0010] The inner wall of the fuel injector is divided into four through spaces, namely, the first space, the second space, the third space, and the fourth space from top to bottom; wherein, the inner diameter of the first space is equal and is used to accommodate the limit ring and the needle valve; the inner diameter of the fourth space is equal and is adapted to part of the outer diameter of the spray hole rotating member; from the second space to the third space, the inner wall of the fuel injector is a tapered frustum toward the third space; the inner wall of the fuel injector in the second space is uniformly provided with inwardly concave guide grooves in the circumferential direction; the contour of the guide rib is adapted to the guide groove; the inner wall of the fuel injector in the third space is provided with a groove, the contour of the groove being adapted to the outer contour of the sealing assembly when not compressed; the axial displacement of the third space is the displacement range of the spray hole rotating member;

[0011] The outer contours formed by the second, third, and fourth spaces are adapted to the outer wall of the end of the spray hole rotating member near the needle valve and the sealing assembly, so that the inner wall of the fuel injection nozzle contacts the outer wall of the end portion of the spray hole rotating member, and the annular surface formed on the bottom wall of the third space (i.e., the top wall of the fourth space) serves as a sealing surface. The axial displacement of the third space is the displacement range of the spray hole rotating member.

[0012] The sealing assembly has elastic potential energy and is located in a groove of a third space formed by the fuel injector and the spray hole rotating member. The lower edge of the flange of the spray hole rotating member contacts the upper edge of the sealing assembly, and can compress or release the sealing assembly at the bottom of the flange of the spray hole rotating member when the spray hole rotating member makes a spiral motion along the guide groove of the inner wall of the fuel injector.

[0013] Furthermore, the upper end of the limiting ring is flush with the upper top surface of the fuel injection nozzle, and the lower end is placed on the upper edge of the guide groove of the spray hole rotating member.

[0014] Furthermore, the lower edge of the flange is at a right angle, so as to better contact the top surface of the sealing assembly.

[0015] Furthermore, the number of the guide grooves is 4-8, and each of the guide grooves is a spiral groove with the same curvature.

[0016] Furthermore, the sealing assembly includes a first sealing plate, a second sealing plate and a return spring having the same height; the first sealing plate and the second sealing plate are both annular sealing plates made of rubber; the return spring is compressed and stretched along the axial direction of the spinning oil nozzle pair.

[0017] A second aspect of the present invention is to provide a fuel injector comprising the aforementioned self-rotating nozzle assembly and a needle valve, wherein high-pressure fuel can flow through a gap between a stop ring and the needle valve; when the needle valve is lifted, the oil pressure pushes the nozzle rotating member to perform a spiral motion along a guide groove on the inner wall of the fuel injector;

[0018] At this time, the nozzle rotating member rotates downward from the upper edge of the third space, and the flange of the nozzle rotating member presses against the sealing assembly to apply downward pressure thereto until the sealing assembly reaches the position where it is most compressed while remaining in a vertical state. During the movement of the nozzle rotating member, fuel is ejected from the nozzle as the nozzle rotating member rotates, while compressing the sealing assembly to store elastic potential energy.

[0019] At the end of fuel injection, as the injection pressure decreases, the sealing assembly releases its elastic force, and the spray hole rotating part rotates upward along the guide groove until it reaches the upper edge of the third space, preparing for the next fuel injection.

[0020] Furthermore, the spray hole has a spray direction selected from the cylinder tangential direction or the cylinder center.

[0021] The shape of the spray hole is selected from one of the following: a narrowing type, a gradually widening type, a gradually narrowing type, a stepped type, a cylindrical type and a special-shaped hole.

[0022] The spray hole is a through hole, and the cross-sectional shape of the spray hole is selected from: a circular hole, an elliptical hole, a rectangular hole, a square hole, a triangular hole and other special-shaped holes.

[0023] The self-spinning nozzle assembly and the fuel injector of the present invention have the following beneficial effects:

[0024] Can fully utilize the injection pressure to realize automatic rotation of the spray hole;

[0025] The inside of the fuel injector is provided with guide grooves and guide ribs, and the rotation of the nozzle rotating part is used to achieve a larger nozzle outlet swirl, so that the spray of liquid fuel has a larger spray cone angle and coverage area, making full use of the combustion chamber space. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1a This is a schematic diagram of the structure of the self-spinning nozzle assembly of the fuel injector of the present invention. Figure 1b yes Figure 1a A cross-sectional view along the AA axis, wherein the lower portion B in the figure shows the lower region of the fuel injection nozzle;

[0027] Figure 2 yes Figure 1b A partial enlarged view of the cross section of the fuel injection nozzle in B;

[0028] Figure 3 is a cross-sectional view of the self-spinning nozzle assembly, wherein the lower portion C in the figure shows the lower region of the nozzle;

[0029] Figure 4 yes Figure 3 A partial enlarged view of the middle C area;

[0030] Figure 5a is a structural diagram of the nozzle rotating member, Figure 5b 2 is a cross-sectional view of the nozzle rotating member.

[0031] Among them, 1: fuel injector; 2: spray hole rotating part; 3: sealing assembly; 4: limit ring; 5: needle valve;

[0032] 6: First sealing plate; 7: Second sealing plate; 8: Return spring; 9: Guide groove; 10: Guide rib;

[0033] 11: first space; 12: second space; 13: third space; 14: fourth space; 15: spray hole; 16: flange. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions, beneficial effects and significant improvements of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the drawings provided in the examples of the present invention. Obviously, all the described embodiments are only partial embodiments of the present invention, rather than all embodiments; based on the demonstrations made in the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field based on the content, implementation methods and drawings of the present invention without making any creative work shall fall within the scope of protection of the present invention.

[0035] It should be noted that the terms "first", "second", "third", etc. in the description and claims of the present invention are only used to distinguish different objects, rather than to describe a specific order.

[0036] It should also be noted that the following specific embodiments may be combined with each other, and the same or similar concepts or processes therein may not be repeated in some embodiments.

[0037] like Figure 1a, 1b, 2-3 shows a fuel injector comprising a self-spinning nozzle assembly and a needle valve 5. The self-spinning nozzle assembly comprises a fuel injector 1, a spray hole rotating member 2, a limiting ring 4 and a sealing assembly 3. The fuel injector 1 is threadedly connected to the fuel injector body through a fastening cap, and the needle valve 5 is inserted into the fuel injector 1. The spray hole rotating member 2 is located below the fuel injector and is dynamically fitted with the fuel injector (clearance fit). The limiting ring 4 is an annular structure, which is arranged in the gap between the outer wall of the needle valve 5 and the inner wall of the fuel injector 1, and the limiting ring and the inner wall of the fuel injector 1 are tightly fitted, so that they are fixed relative to the inner wall of the fuel injector 1. The limiting ring 4 is used to limit the upward movement of the spray hole rotating member 2. Moreover, when no force is applied, the lower bottom surface of the limiting ring 4 is flush with the upper surface of the spray hole rotating member 2. High-pressure fuel flows through the gap between the limiting ring 4 and the needle valve 5.

[0038] like Figure 1b As shown, the inner wall of the fuel injector 1 is divided into four through spaces, namely the first space 11, the second space 12, the third space 13 and the fourth space 14 from top to bottom; the first space has an equal inner diameter, which accommodates the limit ring 4 and the needle valve 5; from the second space to the third space, the inner wall of the fuel injector 1 is a tapered frustum; the fourth space has an equal inner diameter, and the inner diameter of the fourth space is adapted to part of the outer diameter of the spray hole rotating member 2.

[0039] The second space 12 is located below the first space. Multiple inwardly concave guide grooves 9 are uniformly and circumferentially defined on the inner wall of the fuel injector 1 within the second space. Each of these guide grooves is a spiral groove with the same curvature. The third space 13 is located below the second space 12. The inner diameter of the third space 13 is smaller than that of the first and second spaces. Furthermore, an inwardly concave groove is defined on the inner wall of the fuel injector 1 within the third space. The groove accommodates the sealing assembly 3, and the groove's depth matches the thickness of the sealing assembly 3, providing a clearance fit. Furthermore, the axial displacement of the third space 13 corresponds to the displacement range of the nozzle rotating member 2.

[0040] The outer contour formed by the second space 12, the third space 13, and the fourth space 14 is adapted to the outer wall of one end of the spray hole rotating part 2 close to the needle valve and the sealing assembly, so that part of the inner wall of the fuel injector 1 contacts the outer wall of the end part of the spray hole rotating part 2 and is clearance-fitted.

[0041] like Figure 2-45a and 5b, the spray hole rotating member 2 is a cup-shaped structure with a flange 16, which is coaxially arranged in the fuel injector 1. The end of the spray hole rotating member 2 near the needle valve has a flange 16 extending along the circumference of its outer wall, and the lower edge of the flange 16 is at a right angle. The flange 16 of the spray hole rotating member 2 has a protruding guide rib 10. The profile of the guide rib 10 is adapted to the guide groove 9, so that it can slide precisely along the guide groove 9 on the inner wall of the fuel injector 1.

[0042] The sealing assembly 3 includes a first sealing sheet 6, a second sealing sheet 7, and a return spring 8, all of equal height. Both the first and second sealing sheets 6, 7 are annular, rubber-like materials capable of small deformation. After installation, the first sealing sheet 6 rests within the groove in the third space 13 of the fuel injector 1, while the second sealing sheet 7 rests against the outer wall of the nozzle rotating member 2. The return spring 8 is sandwiched between the first and second sealing sheets 6, 7. The return spring compresses and expands along the axial direction of the self-spinning nozzle assembly. The return spring may experience partial torsion due to pressure, but this is not specifically described due to its small floating displacement. Because the first and second sealing sheets 6, 7, and return spring 8 are of equal height, when no downward pressure is applied, the bottom of the flange 16 of the nozzle rotating member 2 contacts the top edge of the sealing assembly 3. As the nozzle rotating member 2 spirals downward along the guide groove 9 on the inner wall of the fuel injector 1, the bottom of the flange 16 of the nozzle rotating member 2 presses against the sealing assembly.

[0043] Furthermore, multiple spray holes 15 are formed on the sidewall of the nozzle rotating member 2, extending through the member. These holes 15 are evenly distributed along the circumference of the member 2 and are inclined, forming a 75° angle with the central axis of the fuel injector 1. Furthermore, the nozzle holes 15 are located on the outer wall of the nozzle rotating member 2, below the fourth space of the fuel injector 1. Therefore, the nozzle holes 15 remain unobstructed by the fuel injector 1 during the movement of the nozzle rotating member 2.

[0044] The working principle of the self-spinning oil nozzle pair is as follows:

[0045] During the injection process, as the needle valve 5 is lifted, high-pressure fuel flows through the gap between the limit ring 4 and the needle valve 5, and the space between the spray hole rotating member 2 and the needle valve 5 is filled with high-pressure fuel. The oil pressure pushes the spray hole rotating member 2 to make a spiral motion along the guide groove 9 on the inner wall of the injector nozzle 1, realizing variable position injection;

[0046] At this time, the spray hole rotating member 2 rotates downward from the upper edge of the third space 13, and the bottom of the flange 16 of the spray hole rotating member 2 presses against the top of the sealing assembly, applying downward pressure thereon, until the first sealing plate 6, the second sealing plate 7, and the return spring 8 are maintained in a vertical state and are at their most compressed position. During the movement of the spray hole rotating member 2, the spray hole 15 is never blocked by the fuel injector 1, and fuel is sprayed from the spray hole 15 as the spray hole rotating member 2 rotates, while compressing the sealing assembly 3 to store elastic potential energy.

[0047] When the fuel injection is finished, as the fuel injection pressure decreases, the sealing assembly 3 releases its elastic force, and the spray hole rotating member 2 rotates and moves upward along the guide groove 9 until it reaches the upper edge of the third space 13, preparing for the next fuel injection.

[0048] Through the above-described structural design, the present invention utilizes injection pressure to achieve automatic rotation of the nozzle, thereby achieving a larger spray cone angle and coverage area for the liquid fuel spray. This significantly increases the oil-gas contact area, achieves highly enhanced atomization, and improves combustion efficiency. Furthermore, the present invention can achieve different rotation paths by adjusting the injection pressure and the parameters of the first sealing plate 6, the second sealing plate 7, and the return spring 8. This provides excellent adjustability and is suitable for optimized injection under different operating conditions.

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents, and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. Non-essential improvements, adjustments or replacements made by those skilled in the art based on the contents of this specification are all within the scope of protection required by the present invention.

Claims

1. A self-spinning oil nozzle assembly, comprising an oil nozzle, characterized in that: The inner wall of the fuel injection nozzle accommodates part of the needle valve, the spray hole rotating member (2) and the sealing assembly (3); A limiting ring (4) is provided in the gap between the outer wall of the needle valve (5) and the inner wall of the fuel injection nozzle (1), and is capable of limiting the upward movement of the spray hole rotating part (2); The spray hole rotating member (2), the needle valve and the limiting ring (4) are coaxially arranged in the fuel injection nozzle (1), and the end of the spray hole rotating member (2) close to the needle valve has a flange (16) extending along the circumferential direction of its outer wall; the outer wall of the flange (16) has a protruding guide rib (10); a plurality of spray holes (15) penetrating the side wall of the spray hole rotating member (2) are opened on the side wall of the spray hole rotating member (2), the spray holes (15) are inclined holes, and the position of the spray holes (15) on the outer wall of the spray hole rotating member (2) is lower than the fourth space of the fuel injection nozzle (1), so that the spray holes (15) can always be not blocked by the fuel injection nozzle (1) during the movement of the spray hole rotating member (2); The inner wall of the fuel injector (1) is divided into four through spaces, namely the first space (11), the second space (12), the third space (13) and the fourth space (14) from top to bottom; wherein the inner diameter of the first space is equal and is used to accommodate the limit ring (4) and the needle valve (5); the inner diameter of the fourth space (14) is equal and is adapted to part of the outer diameter of the injection hole rotating member (2); from the second space (12) to the third space (13), the inner wall of the fuel injector (1) is a tapered cone shape from the second space (12) to the third space (13); the inner wall of the fuel injector (1) in the second space is uniformly provided with an inwardly concave guide groove (9); the contour of the guide rib (10) is adapted to the guide groove (9); the inner wall of the fuel injector (1) in the third space is provided with a groove, the contour of the groove being adapted to the outer contour of the sealing assembly (3) when not compressed; the axial displacement of the third space (13) is the displacement range of the injection hole rotating member (2); The outer contours formed by the second space (12), the third space (13), and the fourth space (14) are adapted to the outer wall of one end of the spray hole rotating member (2) close to the needle valve and the sealing assembly, so that a portion of the inner wall of the fuel injection nozzle (1) contacts the outer wall of the end portion of the spray hole rotating member (2), and the annular surface formed on the bottom wall of the third space (13) serves as a sealing surface, and the axial displacement of the third space (13) is the displacement range of the spray hole rotating member (2); The sealing component (3) has elastic potential energy and is located in a groove of a third space formed by the fuel injection nozzle (1) and the spray hole rotating member (2), and the lower edge of the flange (16) of the spray hole rotating member (2) contacts the upper edge of the sealing component (3). When the spray hole rotating member (2) makes a spiral motion along the guide groove (9) on the inner wall of the fuel injection nozzle (1), the bottom of the flange (16) of the spray hole rotating member (2) can press or release the sealing component (3).

2. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The upper end of the limiting ring (4) is flush with the upper top surface of the fuel injection nozzle (1), and the lower end is placed at the upper edge of the guide groove (9) of the spray hole rotating member (2).

3. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The lower edge of the flange (16) is a right angle.

4. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The number of the guide grooves (9) is 4-8, and each of the guide grooves is a spiral groove with the same curvature.

5. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The sealing assembly (3) comprises a first sealing sheet (6), a second sealing sheet (7) and a return spring (8) of the same height; the first sealing sheet (6) and the second sealing sheet (7) are both annular sealing sheets made of rubber; the return spring (8) is compressed and stretched along the axial direction of the self-spinning oil nozzle pair.

6. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The spray hole has a spray hole direction selected from the cylinder tangential direction or the cylinder center.

7. A fuel injector, characterized in that: The invention comprises the self-rotating nozzle assembly and the needle valve (5) as described in claim 1, wherein high-pressure fuel can flow through the gap between the limit ring (4) and the needle valve (5); when the needle valve (5) is lifted, the oil pressure pushes the nozzle rotating member (2) to perform a spiral motion along the guide groove (9) on the inner wall of the nozzle (1); At this time, the spray hole rotating member (2) rotates downward from the upper edge of the third space (13), and the flange (16) of the spray hole rotating member (2) presses against the sealing component (3) to apply downward pressure thereto until the sealing component (3) reaches the position where the compression is the shortest while the sealing component (3) is kept in a vertical state; during the movement of the spray hole rotating member (2), the fuel is ejected from the spray hole (15) as the spray hole rotating member (2) rotates, and at the same time, the sealing component 3 is compressed to store elastic potential energy; At the end of the fuel injection, as the fuel injection pressure decreases, the sealing assembly (3) releases its elastic force, and the spray hole rotating member (2) rotates and moves upward along the guide groove (9) until it reaches the upper edge of the third space (13), preparing for the next fuel injection.

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