Oil nozzle matching part of self-rotating type oil sprayer and oil sprayer

Abstract

The invention discloses a self-rotating oil nozzle matching part and an oil sprayer. The self-rotating oil nozzle matching part comprises an oil spraying nozzle, a reset spring, a spraying hole rotating part and a limiting piece. A limiting piece, part of the needle valve, a reset spring and a spraying hole rotating piece are contained in a space formed by the inner wall of the oil spraying nozzle. The limiting piece is used for limiting the upward displacement of the spray hole rotating piece; a guide groove and a first oil spraying hole are formed in the inner wall of the oil spraying nozzle in the circumferential direction; the guide grooves are arc-shaped guide grooves with the same curvature, and the first oil spraying hole is a long hole with the section in a rounded rectangle shape. The spraying hole rotating piece is coaxially arranged in the oil spraying nozzle, and the outer wall of the spraying hole rotating piece is provided with a protruding guide rib and a second oil spraying hole; the second oil spraying hole is a through hole and can be always communicated with the first oil spraying hole when the spraying hole rotating piece moves; the two ends of the reset spring abut against the bottom of the inner wall of the oil spray nozzle and the bottom of the spray hole rotating piece respectively. The second oil spraying hole is constantly matched with the first oil spraying hole, and the upper end and the lower end of the first oil spraying hole are the variable distance of the second oil spraying hole.

Description

Technical Field

[0001] The present invention relates to the field of engine fuel injection, and particularly to a spin-type engine nozzle pair and an injector. Background Art

[0002] As a main power machine in the field of transportation, the performance of a diesel engine is directly related to the social labor production efficiency and quality. In the prior art, in order to improve the fuel atomization, evaporation, and mixing uniformity and reduce emissions, high injection pressure and small nozzle hole diameter are generally adopted for injectors. However, the excessively high injection pressure poses higher requirements for the processing and manufacturing of the precision components of the injector. Therefore, it is necessary to start from the structural improvement of the nozzle to optimize the spray performance and combustion.

[0003] Conventional injectors usually have several circular nozzle holes, and the position, angle, and number of the nozzle holes will bring changes to the internal flow path of the injector. However, with the trend of the engine demand towards lightweight and high power density, the single injection quantity increases, so higher injection pressure is applied, resulting in an increase in the spray penetration distance, which will bring the risk of wall impingement in some small-sized engines. Therefore, it is necessary to strengthen the development along the spray radius.

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

[0005] In order to overcome the defects of the prior art, the present invention provides a spin-type nozzle pair and an injector. The nozzle pair can make full use of the injection pressure to realize automatic rotation injection through the nozzle holes.

[0006] The object of the present invention is achieved by the following technical solutions:

[0007] The first aspect of the present invention lies in providing a spin-type nozzle pair, including a nozzle, a return spring, a nozzle hole rotating member, and a limiting piece; the space formed by the inner wall of the nozzle houses the limiting piece, part of the needle valve, the return spring, and the nozzle hole rotating member;

[0008] The limiting piece is fixedly arranged on the inner wall of the nozzle, at a position close to the bottom of the needle valve, and is used to limit the upward displacement of the nozzle hole rotating member;

[0009] A guide groove and a first injection hole are circumferentially formed on the inner wall of the fuel injector; the guide groove is an arc-shaped guide groove with the same curvature, and the central axis of the first injection hole forms an arbitrary angle less than 90 degrees with the central axis of the fuel injector; the first injection hole is a long hole with a fillet rectangle cross-section.

[0010] A nozzle rotating member is coaxially arranged inside the fuel injector. A protruding guide rib and a second injection hole are provided on the outer wall of the nozzle rotating member; the profile and number of the guide ribs are adapted to the guide groove and can move along the arc track of the guide groove; the second injection hole is a through hole and can always communicate with the first injection hole when the nozzle rotating member moves; and the central axes of the first injection hole and the second injection hole have the same angle, and the number of the first injection hole and the second injection hole is the same; both ends of the return spring respectively abut against the bottom of the inner wall of the fuel injector and the bottom of the nozzle rotating member.

[0011] The vertical movement range of the nozzle rotating member is between a first position and a second position. The first position is where the top of the nozzle rotating member is located at the bottom of the limiting piece, and the second position is where the bottom of the nozzle rotating member is located at the position when the return spring is compressed to the shortest in the vertical state.

[0012] Wherein, two through first space and second space are formed on the inner wall of the fuel injector; the inner diameter of the first space is larger than that of the second space, and the second space is close to the bottom of the fuel injector.

[0013] The first space accommodates a limiting piece and part of the needle valve; the limiting piece is fixedly arranged at the junction of the first space and the second space.

[0014] The second space accommodates the return spring and the nozzle rotating member.

[0015] Preferably, the guide groove is a spiral groove.

[0016] Further, the number of the guide grooves is 4 - 8; the number of the first injection holes is 4 - 10.

[0017] Further, the cross-section of the first injection hole is in the shape of a fillet rectangle, and the angle between the long axis of the fillet rectangle and the x-axis is the same as the spiral angle of the guide groove.

[0018] Further, the limiting grooves are evenly formed circumferentially on the inner wall of the fuel injector; and the bottom of the limiting grooves is close to the junction between the first space and the second space.

[0019] Further, in the first space, a plurality of limiting grooves are circumferentially formed on the inner wall of the fuel injector for installing the limiting piece and restricting its displacement.

[0020] Further, the limiting piece is of an annular structure, and a plurality of mounting grooves are evenly formed in the circumferential direction of its inner wall; a plurality of protruding limiting points are evenly arranged in the circumferential direction of the outer wall of the limiting piece, and the limiting points are adapted to the limiting grooves in the first space on the inner wall of the fuel injector nozzle to limit the rotation range of the limiting piece.

[0021] Preferably, the aperture of the first fuel injection hole is slightly larger than that of the second fuel injection hole, and particularly preferably, it is slightly larger than 0.01 mm. The second aspect of the present invention is to provide an injector, including a self-rotating nozzle couple and a needle valve. The cavity between the nozzle rotating part of the self-rotating nozzle couple and the needle valve serves as an oil cavity; when the needle valve is lifted, the nozzle rotating part rotates in an arc along the guide groove, and the second fuel injection hole of the nozzle rotating part moves along the long hole of the first fuel injection hole of the fuel injector nozzle until the nozzle rotating part reaches the second position, realizing variable-position fuel injection; at the end of fuel injection, under the action of the return spring, the nozzle rotating part rotates reversely along the guide groove, so that the nozzle rotating part of the self-rotating nozzle couple reaches the first position;

[0022] During the rotation of the nozzle rotating part, the second fuel injection hole is always in cooperation with the first fuel injection hole, and the upper and lower ends of the first fuel injection hole are the variable distances of the second fuel injection hole.

[0023] In some embodiments, the injection direction of the first fuel injection hole is selected from the tangential direction of the cylinder or the center of the cylinder.

[0024] The shape of the first fuel injection hole is selected from one of the following: constricted type, gradually widened type, gradually tapered type, stepped type, cylindrical type, and special-shaped hole.

[0025] The second fuel injection hole is a through hole, and the cross-sectional shape of its injection hole is selected from: round hole, oval hole, rectangular hole, square hole, triangular hole, and other special-shaped holes.

[0026] When the cross-section of the second fuel injection hole is non-circular, the short axis of the first fuel injection hole is the diameter of the circumscribed circle of the second fuel injection hole.

[0027] The self-rotating nozzle couple and the injector of the present invention have the following beneficial effects:

[0028] It can make full use of the injection pressure to realize automatic rotary fuel injection of the injection holes;

[0029] The fuel injector nozzle is internally provided with a guide groove and a guide rib, and a large swirl at the injection hole outlet is realized by the rotation of the nozzle rotating part, so that the spray of the liquid fuel has a larger spray cone angle and coverage area, and the combustion chamber space is fully utilized. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1a is a schematic structural diagram of the self-rotating nozzle couple of the injector of the present invention, Figure 1b is Figure 1aCross-sectional view along the A-A axis, where the lower part B in the figure shows the fuel injector;

[0031] Figure 2 is Figure 1b a partial enlarged view of the cross-section of the fuel injector at B therein;

[0032] Figure 3a is the cross-sectional view of the spin-type fuel injector coupling; Figure 3b is Figure 3a a partial enlarged view of E therein;

[0033] Figure 4a is the structural schematic diagram of the nozzle rotating part; Figure 4b is Figure 4a the cross-sectional view along the F-F axis;

[0034] Figure 5a is Figure 4a the top view of the shown nozzle rotating part; Figure 5b is Figure 4a the bottom view of the shown nozzle rotating part;

[0035] Figure 6 is the structural schematic diagram of the limit piece.

[0036] Among them, 1: fuel injector; 2: return spring; 3: nozzle rotating part; 4: limit piece; 5: needle valve; 11: first fuel injection hole; 12: return spring seat; 13: guide rib; 14: guide groove; 15: groove; 16: second fuel injection hole; 17: installation groove; 18: limit point; 19: limit groove. Specific embodiments

[0037] To make the objectives, technical solutions, beneficial effects and remarkable progress of the embodiments of the present invention clearer, hereinafter, with reference to the accompanying drawings provided in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, all the described embodiments are only partial embodiments of the present invention, rather than all embodiments; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts according to the content, embodiments and drawings of the present invention belong to the scope of protection of the present invention.

[0038] 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.

[0039] It should also be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0040] As Figure 1a, as shown in Figures 1b and 2, an injector includes a self-rotating nozzle pair and a needle valve 5. The self-rotating nozzle pair includes a nozzle 1, a return spring 2, a spray hole rotating member 3, and a limit piece 4; the nozzle 1 is threadedly connected to the injector body through a fastening cap, the needle valve 5 is inserted into the nozzle 1, and the space between the needle valve 5 and the nozzle 1 houses the return spring 2, the spray hole rotating member 3, and the limit piece 4.

[0041] As Figure 3a - 3b shown, the inner wall of the nozzle 1 has two through spaces, namely a first space and a second space; the inner diameter of the first space is larger than that of the second space; a limit piece 4 is arranged in the first space. The return spring 2 and the spray hole rotating member 3 are arranged in the second space.

[0042] In the first space, a plurality of limit grooves 19 are evenly formed in the circumferential direction on the inner wall of the nozzle 1. The limit grooves 19 are L-shaped grooves for restricting the displacement of the limit piece, and the bottom of the limit groove is close to the junction between the first space and the second space. During installation, first use a tool to extend the limit piece 4 along the limit groove 19 to the bottom of the first space, and then rotate the limit piece 4 along the L-shaped groove of the limit groove 19 to fix the position of the limit piece 4, thereby restricting the up and down displacement of the limit piece.

[0043] In the second space, 4 concave guiding grooves 14 are arranged on the inner wall of the nozzle 1. Each guiding groove 14 is a spiral groove with the same curvature; a return spring seat 12 protruding from the inner wall is arranged on the inner wall at the bottom of the nozzle 1. Moreover, 8 first spray holes 11 are evenly distributed on the outer wall of the nozzle 1. The first spray holes 11 are oblong holes, and the central axis of the first spray hole forms an angle of 75° with the central axis of the nozzle 1. Moreover, the cross-section of the first spray hole is a rounded rectangle, and the angle between the long axis of the rounded rectangle and the x-axis is the same as the spiral angle of the guiding groove 14.

[0044] The spray hole rotating member 3 is of an annular structure and is coaxially arranged in the nozzle 1, and the outer wall of the spray hole rotating member 3 is in contact with the inner wall of the nozzle. 4 protruding guiding ribs 13 are arranged on the outer wall of the spray hole rotating member 3. The profile of the guiding ribs 13 is adapted to the guiding groove 14, so that it can slide precisely along the guiding groove 14 on the inner wall of the nozzle 1. Moreover, there is a groove at the bottom of the spray hole rotating member 3 for nesting one end of the return spring 2.

[0045] A cavity is formed between the bottom of the inner wall of the nozzle 1 and the bottom of the spray hole rotating member 3. The cavity is used to house the return spring 2. One end of the return spring 2 can abut against the bottom of the spray hole rotating member 3, and the other end is sleeved on the return spring seat 12 for resetting the spray hole rotating member 3 to the first position when the fuel injection ends.

[0046] Moreover, as Figure 4a - 4b shown in FIGS. 5a - 5b, eight second fuel injection holes 16 penetrating through the side wall of the nozzle rotating member 3 are formed in the side wall of the nozzle rotating member 3. The second fuel injection holes 16 are uniformly distributed along the circumferential direction of the nozzle rotating member 3, and the second fuel injection holes 16 are inclined holes. The included angle between the second fuel injection holes 16 and the central axis of the fuel injector 1 is 50°. Since the first fuel injection hole 11 is a long hole with a fillet - rectangular cross - section, the second fuel injection holes 16 can always communicate with the first fuel injection holes 11 of the fuel injector 1 during the movement of the nozzle rotating member 3.

[0047] The vertical movement range of the nozzle rotating member 3 is between a first position and a second position. The first position is the bottom of the limiting piece 4, and the second position is the position where the return spring 2 is compressed to the shortest in the vertical state. The nozzle rotating member 3 moves up and down between the first position and the second position. When the top of the nozzle rotating member 3 abuts against the bottom of the limiting piece 4 (i.e., in the first position), the end of the guiding rib of the nozzle rotating member 3 reaches the upper end of the guiding groove, and at this time, the second fuel injection holes 16 on the nozzle rotating member 3 are located at the upper end of the first fuel injection holes 11; when the nozzle rotating member 3 is in the second position, the end of the guiding rib of the nozzle rotating member 3 reaches the lower end of the guiding groove, and at this time, the second fuel injection holes 16 on the nozzle rotating member 3 are located at the lower end of the first fuel injection holes 11.

[0048] As Figure 6 shown, the limiting piece 4 is of an annular structure, and an installation groove 17 is formed along the circumferential direction of its inner wall. Four of the installation grooves 17 are uniformly arranged on the circumferential inner wall of the limiting piece for clamping with the corresponding installation tools; protruding limiting points 18 are uniformly arranged along the circumferential direction of the outer wall of the limiting piece 4. The limiting points 18 are adapted to the limiting grooves 19 in the first space on the inner wall of the fuel injector to limit the rotation range of the limiting piece and prevent over - rotation. Moreover, the limiting piece is located at the top of the nozzle rotating member 3 and also plays a role in protecting the nozzle.

[0049] The working principle of the self - rotating fuel injector is as follows:

[0050] During fuel injection, as the needle valve 5 is lifted, the space between the nozzle rotating member 3 and the needle valve 5 is filled with high - pressure fuel. The oil pressure pushes the nozzle rotating member 3 to perform a spiral motion along the guiding groove 14 on the inner wall of the fuel injector 1, realizing variable - position fuel injection;

[0051] At this time, the nozzle rotating member 3 rotates and moves downward from the first position to the second position. The bottom of the nozzle rotating member 3 is located at the position where the return spring 2 is compressed to the shortest while maintaining a vertical state. During the movement of the nozzle rotating member 3, it is always in communication with the first fuel injection hole 11 of the fuel injector 1. Fuel is ejected from the second fuel injection hole 16 and the first fuel injection hole 11 in sequence, and at the same time, the return spring 2 is compressed to store elastic potential energy.

[0052] When fuel injection ends, as the fuel injection pressure decreases, the return spring 2 releases its elastic force and returns the nozzle rotating member 3 to the first position along the guide groove 14 to prepare for the next fuel injection. During the rotation process, the second fuel injection hole 16 and the first fuel injection hole 11 are constantly matched, and the upper and lower ends of the first fuel injection hole 11 are the variable distance of the second fuel injection hole 16.

[0053] Through the above structural design, the present invention uses the fuel injection pressure to realize the automatic rotation of the nozzle, and uses the second space of the fuel injector 1 to realize a large swirl at the nozzle outlet, so that the spray of the liquid fuel has a larger spray cone angle and coverage area, greatly increasing the oil-gas contact area, achieving a highly enhanced atomization effect, and improving the combustion efficiency. At the same time, the present invention can realize different rotation paths by adjusting the fuel injection pressure and the parameters of the return spring 2, has good adjustability, and is suitable for optimized injection under different working conditions.

[0054] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features, and these modifications or replacements do not make the essence of the corresponding technical solutions 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 according to the content of this specification all fall within the scope claimed by the present invention.

Claims

1. A self-spinning oil nozzle assembly, characterized in that: It comprises a fuel injection nozzle (1), a return spring (2), a spray hole rotating member (3) and a limit plate (4); the fuel injection nozzle (1) contains the limit plate (4), part of the needle valve (5), the return spring (2) and the spray hole rotating member (3); The limiting plate (4) is fixedly arranged on the inner wall of the fuel injection nozzle (1) at a position close to the bottom of the needle valve (5) and is used to limit the upward displacement of the spray hole rotating member (3); The inner wall of the fuel injection nozzle (1) is provided with a guide groove (14) and a first fuel injection hole (11) in the circumferential direction; the guide groove (14) is an arc-shaped guide groove (14) with the same curvature, and the angle between the central axis of the first fuel injection hole (11) and the central axis of the fuel injection nozzle (1) is 45-70 degrees; the first fuel injection hole (11) is a long hole with a rounded rectangular cross section; The spray hole rotating member (3) is coaxially arranged in the fuel injection nozzle (1), and the outer wall of the spray hole rotating member (3) is provided with a protruding guide rib (13) and a second fuel injection hole (16); the contour and number of the guide rib (13) are adapted to the guide groove (14), and can move along the arc track of the guide groove (14); the second fuel injection hole (16) is a through hole, and can always be connected to the first fuel injection hole (11) when the spray hole rotating member (3) moves; and the angles of the central axes of the first fuel injection hole (11) and the second fuel injection hole (16) are the same, and the number of the first fuel injection hole and the second fuel injection hole is the same; the two ends of the return spring (2) are respectively abutted against the bottom of the inner wall of the fuel injection nozzle (1) and the bottom of the spray hole rotating member (3); The vertical movement range of the spray hole rotating member (3) is between a first position and a second position, wherein the first position is when the top of the spray hole rotating member (3) is located at the bottom of the limiting plate (4), and the second position is when the bottom of the spray hole rotating member 3 is located at the position when the return spring (2) is kept in a vertical state and is compressed to the shortest.

2. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The inner wall of the fuel injection nozzle (1) forms two interconnected first spaces and a second space; the inner diameter of the first space is larger than that of the second space, and the second space is close to the bottom of the fuel injection nozzle (1); The first space contains a limit plate (4) and a part of the needle valve (5); the limit plate (4) is fixedly arranged at the junction of the first space and the second space; The second space contains a return spring (2) and a spray hole rotating member (3).

3. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The guide groove is a spiral groove.

4. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The second oil injection hole (16) is permanently matched with the first oil injection hole (11), and the upper and lower ends of the first oil injection hole (11) are at a variable distance from the second oil injection hole (16).

5. The self-spinning oil nozzle assembly according to claim 1, characterized in that: The number of the guide grooves (14) is 4-8; the number of the first oil injection holes (11) is 4-10.

6. The self-spinning oil nozzle assembly according to claim 2, characterized in that: In the first space, a plurality of limiting grooves (19) are circumferentially provided on the inner wall of the fuel injection nozzle 1 for installing a limiting plate (4) and limiting its displacement.

7. A fuel injector, characterized in that The invention comprises a self-spinning oil nozzle pair and a needle valve (5) according to claim 1, wherein the cavity between the spray hole rotating member (3) of the self-spinning oil nozzle pair and the needle valve (5) serves as an oil cavity; when the needle valve (5) is lifted, the spray hole rotating member (3) rotates in an arc shape along the guide groove, and the second oil spray hole (16) of the spray hole rotating member (3) moves along the long hole of the first oil spray hole (11) of the oil nozzle (1) until the spray hole rotating member (3) reaches the second position, thereby realizing variable position oil spraying; when the oil spraying ends, the spray hole rotating member (3) rotates in the opposite direction along the guide groove under the action of the return spring (2), so that the spray hole rotating member (3) of the self-spinning oil nozzle pair reaches the first position; During the rotation of the spray hole rotating member (3), the second spray hole (16) is constantly matched with the first spray hole (11), and the upper and lower ends of the first spray hole (11) are at a variable distance from the second spray hole (16).

8. The fuel injector according to claim 7, characterized in that: The second oil injection hole (16) is a through hole, and the cross-sectional shape of the second oil injection hole (16) is selected from one of the following: a circular hole, an elliptical hole, a rectangular hole, a square hole and a triangular hole.

9. The fuel injector according to claim 8, characterized in that: When the cross-sectional shape of the second oil injection hole (16) is non-circular, the short axis of the first oil injection hole (11) is the diameter of the circumscribed circle of the second oil injection hole (16).

10. The fuel injector according to claim 8, characterized in that The shape of the first oil injection hole (11) is selected from one of the following: a narrowing type, a gradually widening type, a gradually narrowing type, a stepped type or a cylindrical type.

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