Fuel injection needle valve structure of electric fuel injector

Abstract

The utility model provides an oil injection needle valve structure of an electric oil injector, which increases the contact surface area of a lubricating oil film on the premise of the same volume of lubricating oil, and ensures that the circumferential position is stable and reliable when an oil injection needle valve reciprocates. The device comprises a guide section; and a needle portion; a plurality of groups of fish scale ring grooves are formed in the guide section at intervals from top to bottom in the axial length direction, each group of fish scale ring grooves comprises a plurality of concave fish scale grooves, the plurality of fish scale grooves in each group of fish scale ring grooves are uniformly and annularly distributed at equal intervals, and the adjacent fish scale grooves in each group are arranged at intervals through guide supports; all the groups of guide supports are arranged at the same circumferential position, all the fish scale grooves are fish scale grooves in the same shape, and each fish scale groove forms a guide arc groove which transits from the edge to the center.

Description

Technical Field

[0001] This utility model relates to the technical field of electric fuel injector structure, specifically to a fuel injection needle valve structure for an electric fuel injector. Background Technology

[0002] In a high-pressure common rail electric fuel injection system, the injection needle valve is lifted by high-pressure fuel and its opening and closing are controlled by a solenoid valve. It reciprocates up and down along a guide groove in the injector nozzle. Because the tip of the needle is in a high-speed reciprocating sliding state, it requires a well-lubricated, low-friction environment. Existing injection needle valves have annular grooves spaced at intervals in the height direction (see...). Figure 1 The annular groove of the needle valve is used to hold the lubricating oil film. In actual operation, due to the relatively large concave depth of the annular groove, the contact surface area between the entire annular groove and the side wall of the slide rail is relatively small, resulting in relatively limited lubrication function. Furthermore, because it is an annular groove, a circumferential angular deflection may occur when the needle valve reciprocates, which may cause instability in the circumferential position of the needle valve. Therefore, there is an urgent need to develop a needle valve structure that can increase the contact surface area of ​​the lubricating oil film under the same volume of lubricating oil, and ensure the stable and reliable circumferential position of the needle valve during reciprocating motion. Utility Model Content

[0003] To address the aforementioned problems, this utility model provides a fuel injection needle valve structure for an electric fuel injector, which increases the contact surface area of ​​the lubricating oil film while ensuring stable and reliable circumferential position of the fuel injection needle valve during reciprocating motion, provided that the same volume of lubricating oil is used.

[0004] A fuel injection needle valve structure for an electric fuel injector, characterized in that it comprises:

[0005] Guide section;

[0006] And the valve needle part;

[0007] The guide section has multiple sets of fish-scale annular grooves arranged at intervals from top to bottom along the axial length direction. Each set of fish-scale annular grooves includes several concave fish-scale grooves. The fish-scale grooves in each set are evenly and uniformly arranged at equal intervals. Adjacent fish-scale grooves in each set are spaced apart by guide supports. The guide supports of all sets are arranged at the same circumferential position. All fish-scale grooves are fish-scale grooves of the same shape. Each fish-scale groove forms a guide arc groove that transitions from the edge to the center.

[0008] Its further features are:

[0009] Each fish scale groove includes a first semi-elliptical inner groove, a central transition inner groove, and a second semi-elliptical inner groove. The first elliptical side of the first elliptical inner groove is located near the top of the guide section, and the second elliptical side of the second elliptical inner groove is located near the valve needle portion. The eccentricity of the first elliptical side is greater than that of the second elliptical side.

[0010] The first elliptical inner groove is a structure that is symmetrical to each other corresponding to the center line of the circumference. The groove gradually deepens from both sides towards the center line area. The first elliptical side of the first elliptical inner groove is located near the top of the guide section. The upper and lower grooves of the first elliptical inner groove are arranged such that the inner groove gradually deepens from the first elliptical side towards the center.

[0011] The central transition groove is a structure that is symmetrical to each other with respect to the center line of the circumference. The groove gradually deepens from both sides toward the center line area. The upper and lower areas of the central transition groove are set with the same concave depth relative to the same circumferential position.

[0012] The second elliptical inner groove is a structure that is symmetrical to each other with respect to the center line of the circumference. The groove gradually deepens from both sides towards the center line area. The second elliptical side of the second elliptical inner groove is located away from the top of the guide section. The upper and lower grooves of the second elliptical inner groove are arranged such that the inner groove gradually deepens from the second elliptical side towards the center.

[0013] By adopting this utility model, the guide section is arranged with multiple sets of fish-scale annular grooves at intervals along its length. The total concave volume of each set of fish-scale annular grooves is equal to that of the original annular groove. However, since several fish-scale grooves in each set are evenly spaced and arranged in a ring, and each fish-scale groove forms a guide arc groove that transitions from the edge to the center, the surface area of ​​the lubricating oil film formed by each set of fish-scale annular grooves is increased. Thus, under the premise of the same volume of lubricating oil, the contact surface area of ​​the lubricating oil film is increased. Furthermore, since adjacent fish-scale grooves in each set are spaced apart by guide supports, and the guide supports of all sets are arranged at the same circumferential position, circumferential guide support is provided when the fuel injection valve needle moves, ensuring that the circumferential position of the fuel injection needle valve is stable and reliable during reciprocating motion. Attached Figure Description

[0014] Figure 1 A 3D schematic diagram of an existing fuel injection needle valve;

[0015] Figure 2 This is a perspective view of the present invention;

[0016] Figure 3 for Figure 2 A magnified schematic diagram of the structure at point A;

[0017] The names corresponding to the serial numbers in the diagram are as follows:

[0018] Guide section 10, chamfered structure 101, valve needle part 20, fish scale annular groove 30, fish scale groove 40, first semi-elliptical inner groove 41, first elliptical edge 411, central transition inner groove 42, side edge 421, second semi-elliptical inner groove 43, second elliptical edge 431, guide support 50. Detailed Implementation

[0019] A needle valve structure for an electric fuel injector, see Figure 2 and Figure 3 It includes a guide section 10 and a valve needle portion 20;

[0020] The guide section 10 has multiple sets of fish scale annular grooves 30 arranged at intervals from top to bottom along the axial length direction. Each set of fish scale annular grooves 30 includes several concave fish scale grooves 40. The fish scale grooves 40 in each set of fish scale annular grooves 30 are evenly arranged in a ring at equal intervals. The adjacent fish scale grooves 40 in each set are spaced apart by guide supports 50. The guide supports 50 in all sets are arranged at the same circumferential position. All fish scale grooves 40 are fish scale grooves of the same shape. Each fish scale groove 40 forms a guide arc groove that transitions from the edge to the center.

[0021] In a specific embodiment, each fish scale groove 40 includes a first semi-elliptical inner groove 41, a central transition inner groove 42, and a second semi-elliptical inner groove 43. The first elliptical side 411 of the first elliptical inner groove 41 is located near the top of the guide section 10, and the top of the guide section 10 is provided with a chamfer structure 101. The second elliptical side 431 of the second elliptical inner groove 43 is located near the valve needle portion 20, and the eccentricity of the first elliptical side 411 is greater than the eccentricity of the second elliptical side 431.

[0022] The first elliptical inner groove 41 is a structure that is symmetrical to each other corresponding to the center line of the circumference. Its groove gradually deepens from both sides to the center line area. The first elliptical side 411 of the first elliptical inner groove 41 is set near the top of the guide section 10. The upper and lower grooves of the first elliptical inner groove 41 are arranged such that the inner groove 42 gradually deepens from the first elliptical side 411 to the center.

[0023] The central transition groove 42 is a structure that is symmetrical to each other corresponding to the center line of the circumference. The groove gradually deepens from the two sides 421 toward the center line area. The upper and lower areas of the central transition groove 42 are set with the same concave depth relative to the same circumferential position.

[0024] The second elliptical inner groove 43 is a structure that is symmetrical to the center line of the circumference. Its groove gradually deepens from both sides towards the center line area. The second elliptical side 431 of the second elliptical inner groove 43 is located away from the top of the guide section 10. The upper and lower grooves of the second elliptical inner groove 43 are arranged such that the inner groove 42 gradually deepens from the second elliptical side 431 towards the center.

[0025] Its working principle is as follows: The guide section is arranged with multiple sets of fish-scale annular grooves at intervals along its length. The total concave volume of each set of fish-scale annular grooves is equal to that of the original annular groove. However, since several fish-scale grooves in each set are evenly spaced and arranged in a ring, and each fish-scale groove forms a guide arc groove that transitions from the edge to the center, the surface area of ​​the lubricating oil film formed by each set of fish-scale annular grooves is increased. Thus, under the premise of the same volume of lubricating oil, the contact surface area of ​​the lubricating oil film is increased. Furthermore, since adjacent fish-scale grooves in each set are spaced apart by guide supports, and all sets of guide supports are arranged at the same circumferential position, circumferential guide support is provided when the fuel injection valve needle moves, ensuring that the circumferential position of the fuel injection needle valve is stable and reliable during reciprocating motion.

[0026] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0027] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A needle valve structure for an electric fuel injector, characterized in that, It includes: Guide section; and the valve needle part; The guide section has multiple sets of fish-scale annular grooves arranged at intervals from top to bottom along the axial length direction. Each set of fish-scale annular grooves includes several concave fish-scale grooves. The fish-scale grooves in each set are evenly and uniformly arranged at equal intervals. Adjacent fish-scale grooves in each set are spaced apart by guide supports. The guide supports of all sets are arranged at the same circumferential position. All fish-scale grooves are fish-scale grooves of the same shape. Each fish-scale groove forms a guide arc groove that transitions from the edge to the center.

2. The injection needle valve structure of an electric fuel injector according to claim 1, characterized in that: Each fish scale groove includes a first semi-elliptical inner groove, a central transition inner groove, and a second semi-elliptical inner groove. The first elliptical side of the first elliptical inner groove is located near the top of the guide section, and the second elliptical side of the second elliptical inner groove is located near the valve needle portion. The eccentricity of the first elliptical side is greater than the eccentricity of the second elliptical side.

3. The injection needle valve structure of an electric fuel injector according to claim 2, characterized in that: The first elliptical inner groove is a structure that is symmetrical to each other with respect to the center line of the circumference. The groove gradually deepens from both sides towards the center line area. The first elliptical side of the first elliptical inner groove is located near the top of the guide section. The upper and lower grooves of the first elliptical inner groove are arranged such that the inner groove gradually deepens from the first elliptical side towards the center.

4. The injection needle valve structure of an electric fuel injector according to claim 2, characterized in that: The central transition groove is a structure that is symmetrical to the center line of the circumference. The groove gradually deepens from both sides towards the center line area. The upper and lower areas of the central transition groove are set with the same concave depth relative to the same circumferential position.

5. The injection needle valve structure of an electric fuel injector according to claim 2, characterized in that: The second elliptical inner groove is a structure that is symmetrical to each other with respect to the center line of the circumference. The groove gradually deepens from both sides towards the center line area. The second elliptical side of the second elliptical inner groove is located away from the top of the guide section. The upper and lower grooves of the second elliptical inner groove are arranged such that the inner groove gradually deepens from the second elliptical side towards the center.

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