CN112377345A

CN112377345A - Injection valve

Info

Publication number: CN112377345A
Application number: CN202011379424.5A
Authority: CN
Inventors: 陈楠; 王凌云; 金昱森; 臧娈; 周庭波; 胡凯耀
Original assignee: FAW Jiefang Automotive Co Ltd
Current assignee: FAW Jiefang Automotive Co Ltd
Priority date: 2020-11-30
Filing date: 2020-11-30
Publication date: 2021-02-19
Anticipated expiration: 2040-11-30
Also published as: CN112377345B

Abstract

The invention belongs to the technical field of engines, and particularly relates to an injection valve which comprises an injector body, a valve sleeve, a needle valve body, a long needle valve and a lift adjusting assembly, wherein the injector body is provided with a valve seat; the injector body is provided with a high-pressure cavity, the valve sleeve and the needle valve body block two ends of the high-pressure cavity, and the long needle valve is slidably arranged in the valve sleeve and the needle valve body; the valve sleeve is provided with a first end surface positioned in the high-pressure cavity, and one end of the needle valve body, which is far away from the valve sleeve, is provided with a jet hole; a control cavity is formed between the long needle valve and the valve sleeve, the long needle valve is provided with a supporting section and a sealing section, the supporting section is provided with a supporting ring, and the sealing section is used for periodically plugging the spray hole along with the sliding of the long needle valve; the lift adjusting assembly is detachably sleeved outside the supporting section and is positioned between the first end face and the supporting ring; when the sealing section blocks the spray hole, a distance H1 is reserved between one end, away from the support ring, of the lift adjusting assembly and the first end face. The injection valve provided by the invention overcomes the defect of static leakage of the injection valve, can adjust the lift of the needle valve, and is convenient to assemble and debug parts.

Description

Injection valve

Technical Field

The invention relates to the technical field of engines, in particular to an injection valve.

Background

Injection valves are commonly used in high pressure common rail injection systems for engines to inject high pressure fuel from a high pressure accumulator into a diesel engine cylinder. The existing mainstream injection valve mostly adopts a long needle valve structure and comprises a long needle valve, a needle valve body, an injector body, a control valve sleeve and the like, and in the process of assembling the injector assembly with the structure, the sizes of the control valve sleeve, the injector body and the needle valve body need to be respectively measured, and the sizes are matched to ensure that the needle valve lift can be assembled. The existing assembly process has the problems that the matching processing needs to be accurately carried out before the assembly, the processing process is complex, the requirement is strict, the requirement on the processing size of each part is high, the rejection rate is high, and the processing cost is high. In addition, the injection valve of this kind of structure can't restrict the lift of long needle valve, leads to long needle valve working process in striking valve barrel bottom repeatedly, and the impact that long needle valve top received is great, easily causes the wearing and tearing and the coating at long needle valve top to drop, leads to the injection valve to appear the needle valve jamming phenomenon. In addition, the injection valve with the structure cannot adjust the lift of the needle valve at any time, the consistency of the oil quantity performance of the injection valve is greatly influenced, and if lift parameters are changed, the injection valve needs to be replaced in a whole set, so that the cost is high.

Disclosure of Invention

The invention aims to provide an injection valve, which overcomes the defect of static leakage of the traditional injection valve and can adjust the lift of a needle valve.

In order to achieve the purpose, the invention adopts the following technical scheme:

an injection valve comprising:

an injector body having a high pressure chamber for containing fuel;

the valve sleeve seals one end of the high-pressure cavity and is provided with a first accommodating cavity; said valve housing having a first end surface located within said high pressure chamber;

the needle valve body is used for plugging the other end of the high-pressure cavity and is provided with a second accommodating cavity; one end of the needle valve body, which is far away from the valve sleeve, is provided with a jet hole;

the long needle valve is slidably arranged in the first accommodating cavity and the second accommodating cavity, and a control cavity is formed between the long needle valve and the valve sleeve; the long needle valve is provided with a supporting section and a sealing section, and the supporting section is provided with a supporting ring; the sealing section can periodically block the spray hole along with the sliding of the long needle valve; and

the lift adjusting assembly is detachably sleeved outside the supporting section and is positioned between the first end face and the supporting ring; when the sealing section blocks the spray hole, a distance H1 is reserved between one end, away from the support ring, of the lift adjusting assembly and the first end face.

In a preferred embodiment of the present invention, the H1 is 0.3mm to 0.35 mm.

As a preferable structure of the invention, the lift adjusting assembly comprises a pre-tightening force adjusting gasket pressure adjusting spring and a lift adjusting sleeve, the pre-tightening force adjusting gasket is abutted against the support ring, the pressure adjusting spring is sleeved outside the support section, and the lift adjusting sleeve is sleeved outside the pressure adjusting spring.

In a preferred configuration of the present invention, the lift adjusting sleeve has an axial length of 10mm to 11 mm.

As a preferable structure of the present invention, an inner diameter of the lift adjusting sleeve is smaller than an outer diameter of the preload adjusting washer; the outer diameter of the lift adjusting sleeve is larger than that of the pretightening force adjusting gasket and smaller than that of the first end face.

As a preferred structure of the invention, the long needle valve has an integrated structure, and comprises a long needle valve head, a sealing cylindrical surface section, the supporting ring, a connecting section, a guiding section and the sealing section which are connected in sequence; the sealing cylindrical surface section is matched with the first accommodating cavity through a matching part; the guide section and the second accommodating cavity are also matched by a matching part.

As a preferable structure of the invention, the control cavity is provided with an oil inlet hole and an oil return hole, and the high-pressure cavity is communicated with the control cavity through the oil inlet hole; the control cavity is communicated with an external oil return pipeline through the oil return hole.

As a preferred structure of the invention, the control cavity comprises an arc-shaped section and a sink groove, the arc-shaped section is connected with the sink groove, and the sink groove is communicated with the oil return hole; when the long needle valve slides in the first accommodating cavity, the arc surface of the head of the long needle valve is periodically abutted to the arc section.

As a preferable structure of the present invention, the guide section has a spiral oil inlet groove, and the high pressure chamber communicates with the nozzle hole through the spiral oil inlet groove.

As a preferable structure of the present invention, the present invention further includes a control valve assembly configured to control opening and closing of the oil return hole.

The invention has the beneficial effects that: according to the injection valve provided by the invention, the valve sleeve and the needle valve body are used for plugging two ends of the high-pressure cavity of the injector body, so that the defect of static leakage of the traditional injection valve is overcome; the long needle valve is provided with a supporting section with a supporting ring, a detachable lift adjusting component is sleeved outside the supporting section, and the lift adjusting component can slide between the supporting ring and a valve sleeve along with the long needle valve and is used for adjusting the lift H1 of the long needle valve; the injection valve adjusts the lift of the long needle valve through the lift adjusting assembly, has simple, compact and reasonable structure, is convenient for assembling and debugging parts, is easier to control in processing and manufacturing compared with the prior art, reduces the processing and labor cost, improves the assembly consistency and the qualification rate of the injector, and realizes a simple and efficient production mode.

Drawings

FIG. 1 is a cross-sectional view of an injection valve assembly provided by an embodiment of the present invention;

FIG. 2 is a partial cross-sectional view of an injection valve provided in accordance with an embodiment of the present invention;

FIG. 3 is a partial cross-sectional view of an injection valve assembly provided in accordance with an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a long needle valve provided in an embodiment of the present invention;

fig. 5 is a cross-sectional view of a valve sleeve provided in accordance with an embodiment of the present invention;

FIG. 6 is a cross-sectional view of a lift adjustment sleeve provided in accordance with an embodiment of the present invention;

fig. 7 is a top view of fig. 6.

In the figure:

1. an injector body; 11. a high pressure chamber; 12. an injector oil inlet hole;

2. a valve housing; 21. a first end face; 22. a control chamber; 221. an arc-shaped section; 222. sinking the tank; 23. an oil inlet hole; 24. an oil return hole; 25. a first accommodating chamber; 26. a third end face;

3. a needle valve body; 31. spraying a hole; 32. a second end face; 33. a second accommodating chamber;

4. a long needle valve; 41. a support section; 42. a support ring; 43. a sealing section; 44. a needle valve head; 45. sealing the cylindrical surface section; 46. a connecting section; 47. a guide section; 471. a spiral oil inlet groove;

5. a lift adjustment assembly; 51. a pre-tightening force adjusting gasket; 52. a pressure regulating spring; 53. a lift adjusting sleeve;

6. a control valve assembly; 61. an armature rod; 62. an armature plate; 63. a control valve seat; 631. a first oil return channel; 632. an oil return channel II; 64. a ball seat; 65. a pellet; 66. a damping shim; 67. a damping spring.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are used based on the orientations and positional relationships shown in the drawings only for convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

Example one

As shown in fig. 1 to 7, an embodiment of the present invention provides an injection valve including an injector body 1, a valve housing 2, a needle valve body 3, a long needle valve 4, and a lift adjustment assembly 5. The injector body 1 is provided with a high-pressure cavity 11 for containing fuel, an injector oil inlet hole 12 communicated with the high-pressure cavity 11 is formed in the side wall of the injector body 1, and high-pressure fuel enters the high-pressure cavity 11 through the injector oil inlet hole 12. One end opening of the high pressure chamber 11 is closed by the valve housing 2, the valve housing 2 has a first accommodating chamber 25 inside, the valve housing 2 has a first end surface 21 and a third end surface 26 located in the high pressure chamber 11, the third end surface 26 is a shoulder blade surface of the valve housing 2, and as shown in fig. 1, the third end surface 26 abuts against one end surface of the injector body 1. The other end of the injector body 1 is provided with a needle valve body 3, and the needle valve body 3 is provided with a second accommodating cavity 33; the needle valve body 3 has a nozzle hole 31 at its end remote from the valve housing 2. Preferably, the plurality of injection holes 31 are distributed on the tapered surface of the end of the needle valve body 3. The nozzle hole 31 can be selectively opened or closed so that the injection valve is in an open state or a closed state. The needle valve body has a second end face 32, the second end face 32 abutting the other end face of the injector body 1 remote from the valve sleeve 2.

One end of the long needle valve 4 is positioned in the first accommodating cavity 25 of the valve housing 2, and a control cavity 22 is formed between the top of one end of the long needle valve 4 and the valve housing 2; the control cavity 22 is provided with an oil inlet hole 23 and an oil return hole 24, and the high-pressure cavity 11 is communicated with the control cavity 22 through the oil inlet hole 23; the control chamber 22 communicates with an external return line via a return orifice 24. High-pressure fuel can rapidly enter the control cavity 22 through the fuel inlet hole 23, and the closing delay of the injection valve can be greatly reduced. The other end of the long needle valve 4 is located in the second accommodating chamber 33 of the needle valve body 3, and the long needle valve 4 is slidable in the first accommodating chamber 25 and the second accommodating chamber 33. The long needle valve 4 is provided with a support section 41 and a support ring 42, wherein the support section 41 is connected with the support ring 42; preferably, the support ring 42 is an annular boss. The long needle valve 4 further has a sealing section 43, the sealing section 43 is located at one end portion of the long needle valve 4, and when the long needle valve 4 slides in the first accommodating chamber 25 and the second accommodating chamber 33, the tapered surface of the sealing section 43 periodically blocks the nozzle hole 31, so that the injection valve is in an open state or a closed state.

The lift adjusting assembly 5 is detachably sleeved outside the supporting section 41, and the lift adjusting assembly 5 is located between the first end surface 21 of the valve sleeve 2 and the supporting ring 42. When the sealing section 43 blocks the nozzle hole 31, the long needle valve 4 closes the injection valve, and at this time, the distance between the end of the lift adjustment assembly 5 away from the support ring 42 and the first end face 21 is H1, where H1 is the maximum lift of the long needle valve 4. The lift adjusting assembly 5 can move longitudinally along with the long needle valve 4, and the top dead center of the longitudinal movement is the first end surface 21 of the valve sleeve 2, that is, when the long needle valve 4 moves the lift H1 to reach the top dead center, the lift adjusting assembly 5 can abut against the first end surface 21. Preferably, according to the requirement of working conditions, the lift H1 of the injection valve is 0.3 mm-0.35 mm, and the H1 can be adjusted by selecting lift adjusting assemblies 5 with different axial lengths. The lift adjusting assembly 5 is arranged, so that the lift of the long needle valve 4 can be flexibly adjusted, the processing requirements on other parts are reduced, and the processing and labor cost is reduced.

Preferably, the lift adjusting assembly 5 includes a preload adjusting washer 51, a pressure adjusting spring 52 and a lift adjusting sleeve 53, the preload adjusting washer 51 abuts against the supporting ring 42, the pressure adjusting spring 52 is sleeved outside the supporting section 41, and the lift adjusting sleeve 53 is sleeved outside the pressure adjusting spring 52. One end of the pressure adjusting spring 52 abuts against the first end surface 21 of the valve housing 2, and the other end presses the preload adjusting washer 51 against the support ring 42 of the long needle valve 4. Further preferably, the inner diameter of the lift adjusting sleeve 53 is smaller than the outer diameter of the pretightening force adjusting gasket 51; the outer diameter of the lift adjusting sleeve 53 is larger than that of the preload adjusting washer 51 and smaller than that of the first end surface 21. The outer diameter of the lift adjusting sleeve 53 is prevented from being too large to throttle high-pressure oil inlet.

Preferably, the axial length of the lift adjusting sleeve 53 is 10 mm-11 mm, and the lift adjusting sleeve 53 has a size selectable series with an adjusting gradient of 0.02 mm. According to design requirements, the lift adjusting sleeve 53 can be divided into a plurality of size gradients, and the lift adjusting sleeves 53 with different sizes are selected according to the sizes of the injector body 1, the valve sleeve 2, the long needle valve 4 and the needle valve body 3 with different processing deviations, so that different needle valve lifts can be adjusted. The calculation process for selecting the size of the lift adjustment sleeve 53 is as follows:

as shown in fig. 2 and 3, the dimension of the lift adjusting sleeve 53 is set to H4, and the lift H1 of the long needle valve 4 is selected for the height dimension of H4, and the following critical dimensions need to be measured in the calculation and selection process: the distance H2 between the end faces of the two ends of the injector body 1 and the thickness H7 of the pretightening force adjusting gasket 51; assuming that the valve housing 2, the long needle valve 4 and the needle valve body 3 are assembled into a three-piece member, and the dimension H8 between the second end surface 32 and the third end surface 26 when the three-piece member is in a compressed state (i.e., the long needle valve 4 cannot slide up and down), assuming that the valve housing 2, the long needle valve 4 and the needle valve body 3 are assembled into a three-piece member, and the dimension H3 between the first end surface 21 and the support ring 42 when the three-piece member is in a compressed state (i.e., the long needle valve 4 cannot slide up and down), the height gradient H4 of the lift adjustment sleeve 53 can be determined according to the above dimensions:

when the lift adjusting assembly 5 is not arranged, the lift of the long needle valve 4 is H2-H8;

after the lift adjustment assembly 5 is provided, the dimension H4 of the lift adjustment sleeve 53 is H3+ H2-H8-H7-H1. Wherein, H1 should be 0.3-0.35 mm, preferably, during processing, H4 can be selected by taking 0.02mm as an adjusting gradient, and the size is ensured to be 10-11 mm.

Preferably, the long needle valve 4 has an integrated structure including a long needle valve head 44, a sealing cylindrical section 45, a support section 41, a support ring 42, a connecting section 46, a guide section 47 and a sealing section 43, which are connected in sequence. The long needle valve 4 of the integrated structure reduces the number of moving parts and improves the response speed of the needle valve movement. Matching parts are matched between the sealing cylindrical surface section 45 and the first accommodating cavity 25, and the matching gap is 0.003-0.012 mm; the guide section 47 is matched with the second accommodating cavity 33 through a matching part, and the matching clearance is 0.002-0.015 mm; the long needle valve 4 is immersed in the high-pressure fuel in the high-pressure chamber 11 except for the sealing cylindrical section 45 and the guide section 47. Therefore, the clearances between the long needle valve 4 and the valve housing 2 and between the long needle valve 4 and the needle valve body 3 are extremely small, and the high-pressure fuel is not enough to deliver enough fuel to the two end parts of the long needle valve 4 through the two clearances, thereby ensuring that the injection valve has no static leakage. The matching parts of the long needle valve 4 and the first accommodating cavity 25 and the matching parts of the long needle valve 4 and the second accommodating cavity 33 are simple in structure, effective support is provided for continuous and stable oil injection quantity of the injection valve, the long needle valve can be realized by using smaller cost in machining, and the long needle valve has higher economical efficiency. The clamping stagnation of the matching parts in the installation and working processes can be avoided by controlling the two matching gaps.

Further, the control chamber 22 includes an arc-shaped section 221 and a sink 222, the arc-shaped section 221 is connected with the sink 222, and the sink 222 is communicated with the oil return hole 24. The arc surface of the long needle valve head 44 periodically abuts the arc-shaped section 221 when the long needle valve 4 slides in the first accommodation chamber 25. The arc-shaped section 221 is abutted against the arc surface of the long needle valve head 44, so that energy loss caused by dynamic fuel leakage can be effectively reduced.

Further, the guide section 47 has a spiral oil inlet groove 471, and the high pressure chamber 11 communicates with the injection hole 31 through the spiral oil inlet groove 471. Preferably, the spiral oil inlet groove 471 is formed on the outer surface of the guide section 47 and penetrates both ends of the guide section 47 to form a 180-degree spiral. Through spiral oil feed groove 471, make things convenient for high-pressure fuel to get into the tip of long needle valve 4 from high-pressure chamber 11, avoided setting up oil feed way and flourishing oil groove in the inside of needle valve body 3, and the needle valve body 3 fracture risk that leads to from this.

Further, the injection valve further includes a control valve assembly 6, and the control valve assembly 6 is configured to control opening and closing of the oil return hole 24. The control valve assembly 6 includes an armature rod 61, an armature plate 62, a control valve seat 63, a ball seat 64, a ball 65, a damping washer 66 and a damping spring 67. A control valve seat hole is formed in the center of the control valve seat 63, and the armature rod 61 extends into the valve seat hole and can axially move along the valve seat hole, so that the armature sheet 62 is driven to axially move; the armature rod 61 presses the ball seat 64 and the sealing small ball 65 on the sealing conical surface at the upper part of the valve housing 2 to block the oil return hole 24 and ensure the high-pressure sealing of the control cavity 22. The control valve seat 63 is provided with a first oil return passage 631 and a second oil return passage 632, and when the sealing ball 65 opens the oil return hole 24, the high-pressure fuel in the control chamber 22 flows through the oil return hole 24 and flows into the external oil return line through the first oil return passage 631 and the second oil return passage 632. The damping washer 66 and damping spring 67 provide further cushioning as the armature rod 61 drives the armature plate 62 down and against the ball 65.

The operation of the injection valve is as follows: in an initial state, the small ball 65 blocks the oil return hole 24, the control cavity 22 is filled with high-pressure fuel oil, and the long needle valve 4 is positioned at the bottom dead center and blocks the spray hole 31; when the electromagnet is electrified, the armature rod 61 drives the armature sheet 62 and the ball seat 64 to move upwards, the small ball 65 lifts and opens the oil return hole 24, the high-pressure fuel in the control cavity 22 sequentially passes through the oil return hole 24, the oil return channel I631 and the oil return channel II 632 and flows into an external oil return pipeline, the pressure in the control cavity 22 rapidly drops, the acting force acting on the needle valve head 44 is reduced, the long needle valve 4 moves upwards from the bottom dead center, when the long needle valve 4 moves upwards to the state that the lift adjusting sleeve 53 is in contact with the first end face 21 of the valve sleeve 2, the upward movement is stopped, and the upper dead center is reached, and at the moment, the lift of the long needle valve 4 is H1; high-pressure fuel enters the spray hole 31 of the needle valve body 3 through the spiral fuel inlet groove 471 and starts to spray fuel; when the work is finished, the electromagnet is powered off, the armature rod 61 drives the armature sheet 62 and the ball seat 64 to move downwards, the small ball 65 is pressed on the sealing conical surface of the valve sleeve 2 and blocks the oil return hole 24, and the high-pressure sealing of the control cavity 22 is ensured; at this time, high-pressure fuel enters the control chamber 22 through the oil inlet hole 23 of the valve housing 2, the long needle valve 4 moves downward under the pressure of the control chamber 22 and the pre-tightening force of the pressure adjusting spring 52, and the movement is stopped when the sealing section 43 of the long needle valve 4 contacts the nozzle hole 31 of the needle valve body 3, thereby completing a fuel injection process.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, adaptations and substitutions will occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An injection valve, comprising:

an injector body (1) having a high-pressure chamber (11) for containing fuel;

a valve housing (2) closing off one end of the high-pressure chamber (11), the valve housing (2) having a first receiving chamber (25); said valve housing (2) having a first end surface (21) located in said high pressure chamber (11);

the needle valve body (3) is used for plugging the other end of the high-pressure cavity (11), and the needle valve body (3) is provided with a second accommodating cavity (33); one end of the needle valve body (3) far away from the valve sleeve (2) is provided with a spray hole (31);

the long needle valve (4) is slidably mounted in the first accommodating cavity (25) and the second accommodating cavity (33) and forms a control cavity (22) with the valve sleeve (2); the long needle valve (4) is provided with a supporting section (41) and a sealing section (43), and a supporting ring (42) is arranged on the supporting section (41); the sealing section (43) can periodically block the spray hole (31) along with the sliding of the long needle valve (4); and

the lift adjusting assembly (5) is detachably sleeved outside the supporting section (41), and the lift adjusting assembly (5) is positioned between the first end surface (21) and the supporting ring (42); when the sealing section (43) blocks the spray hole (31), a distance H1 is reserved between one end of the lift adjusting assembly (5) far away from the support ring (42) and the first end face (21).

2. The injection valve of claim 1 wherein said H1 is between 0.3mm and 0.35 mm.

3. The injection valve according to claim 1, wherein the lift adjustment assembly (5) comprises a preload adjustment gasket (51), a pressure adjustment spring (52) and a lift adjustment sleeve (53), the preload adjustment gasket (51) abuts against the support ring (42), the pressure adjustment spring (52) is sleeved outside the support section (41), and the lift adjustment sleeve (53) is sleeved outside the pressure adjustment spring (52).

4. The injection valve as claimed in claim 3, characterized in that the axial length of the lift adjustment sleeve (53) is 10mm to 11 mm.

5. The injection valve as claimed in claim 3, characterized in that the lift adjustment sleeve (53) has an inner diameter which is smaller than the outer diameter of the pretension adjusting washer (51); the outer diameter of the lift adjusting sleeve (53) is larger than that of the pretightening force adjusting gasket (51) and smaller than that of the first end surface (21).

6. The injection valve according to claim 1, wherein the long needle valve (4) has an integral structure including a long needle valve head (44), a sealing cylindrical section (45), the support section (41), the support ring (42), a connecting section (46), a guide section (47), and the sealing section (43) connected in sequence; the sealing cylindrical surface section (45) is matched with the first accommodating cavity (25) by a matching part; the guide section (47) and the second accommodating cavity (33) are also matched by a matching part.

7. The injection valve according to claim 6, wherein the control chamber (22) has an oil inlet hole (23) and an oil return hole (24), and the high pressure chamber (11) communicates with the control chamber (22) through the oil inlet hole (23); the control cavity (22) is communicated with an external oil return pipeline through the oil return hole (24).

8. The injection valve according to claim 7, wherein the control chamber (22) comprises an arc-shaped section (221) and a sink (222), the arc-shaped section (221) is connected with the sink (222), and the sink (222) is communicated with the oil return hole (24); when the long needle valve (4) slides in the first accommodating cavity (25), the arc surface of the head part (44) of the long needle valve is periodically abutted to the arc section (221).

9. The injection valve according to claim 6, wherein the guide section (47) has a spiral oil feed groove (471), and the high pressure chamber (11) communicates with the injection hole (31) through the spiral oil feed groove (471).

10. An injection valve according to claim 7, characterized in that it further comprises a control valve assembly (6), said control valve assembly (6) being configured to control the opening and closing of said oil return hole (24).