Control valve structure and dual-fuel injector assembly

Abstract

The utility model belongs to the technical field of ejectors, and particularly discloses a control valve structure which comprises an ejector body provided with a control cavity. The valve seat assembly is arranged in the ejector body and comprises a valve seat and an armature, the valve seat is provided with a valve seat hole, and the armature slides along the valve seat hole; the valve seat is provided with an oil containing groove communicated with the valve seat hole, fuel enters the control cavity through the oil containing groove, and a conical surface structure is arranged between the oil containing groove and the control cavity. The metering valve is arranged below the valve seat and provided with a first oil channel, along with lifting or falling of the armature, the conical surface structure closes or opens a circulation channel of the oil containing groove and the control cavity, and meanwhile the armature opens or closes the circulation channel of the first oil channel and the control cavity. According to the control valve structure, fuel oil flows out of the control cavity quickly, and therefore the opening time of the needle valve is shortened. The utility model further discloses a dual-fuel injector assembly.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of injector, concretely relates to a control valve structure and dual fuel injector assembly. BACKGROUND

[0002] The main function of the fuel injector is to inject fuel into the combustion chamber to control the combustion process. How to complete the fuel injection action in a very short time is the goal that the industry personnel have been striving for.

[0003] In 2020, our company submitted a Chinese invention patent, public number CN111535964B, a common rail fuel injector with fast switching function. When fuel injection, the electromagnetic control valve is powered on, the armature is attracted upward by the electromagnetic control valve, the armature shaft is lifted upward, the upper part of the steel ball loses support, the high-pressure fuel in the oil outlet measuring hole lifts the steel ball, the oil outlet measuring hole is opened, and the fuel is discharged outward through the oil outlet measuring hole. Because the fuel discharged from the oil outlet measuring hole is greater than the fuel entering from the oil inlet measuring hole and the oil inlet adjusting hole, the fuel pressure in the control valve sleeve decreases rapidly, the needle valve is lifted by the high-pressure fuel at the lower part, and the nozzle is opened. During this process, as the needle valve goes up, the lower section of the guide area gradually blocks the oil inlet adjusting hole until the oil inlet adjusting hole is completely closed, so that the amount of fuel entering the control valve sleeve gradually decreases, which further increases the difference between the amount of fuel flowing out of the oil outlet measuring hole and the amount of fuel entering the control valve sleeve. Correspondingly, the fuel pressure difference between the upper end and the lower end of the needle valve also increases, so that the needle valve can quickly go up, the nozzle quickly reaches the maximum opening state, and a large amount of fuel is quickly injected and burned.

[0004] In use, it is found that the following problems still exist: when the electromagnetic valve is powered on for fuel injection, the amount of fuel entering the control valve sleeve is gradually reduced, and fuel still enters the control chamber, the pressure in the control chamber decreases slowly, and the needle valve opens for a long time, which is not conducive to improving the response performance. Utility model content

[0005] The utility model aims at providing a control valve structure, fuel quickly flows out of the control chamber, thereby reducing the opening time of the needle valve.

[0006] The utility model aims at realizing the technical scheme, and specifically provides a control valve structure, which comprises:

[0007] The injector body is provided with a control chamber;

[0008] The valve seat assembly is arranged in the injector body and comprises a valve seat and an armature, and the valve seat is provided with a valve seat hole; the valve seat is provided with an oil holding groove in communication with the valve seat hole, fuel enters the control chamber through the oil holding groove, and a conical surface structure is arranged between the oil holding groove and the control chamber;

[0009] The metering valve is arranged below the valve seat and is provided with a first oil channel,

[0010] With the lifting or falling of the armature along the valve seat hole, the conical surface structure closes or opens the flow passage between the oil groove and the control chamber, and the armature opens or closes the flow passage between the first oil channel and the control chamber.

[0011] Preferably, the conical surface structure comprises a conical surface arranged on the armature and a seat surface arranged on the valve seat and matched with the conical surface, and the seat surface and the conical surface are preset with an angle.

[0012] Preferably, the angle is 0.5°.

[0013] Preferably, the injector body is provided with an oil return channel, and the upper end surface of the valve seat hole is provided with a first groove in communication with the oil return channel; the first groove and the oil groove are in communication.

[0014] Preferably, a buffer groove is arranged in the flow passage between the oil groove and the control chamber.

[0015] Preferably, the end surface of the metering valve is provided with a first metering hole and a second metering hole, the first metering hole is in communication with the control chamber and the buffer groove, and the second metering hole is in communication with the first oil channel.

[0016] Preferably, the first metering hole is provided with a second oil channel in the control chamber, and the diameter of the second oil channel is greater than that of the first metering hole.

[0017] Preferably, the lower end surface of the armature is provided with a second groove.

[0018] Due to the adoption of the above technical scheme, the utility model has the following advantages:

[0019] The control valve structure of the utility model, by setting the conical surface structure, with the lifting or falling action of the armature to dynamically close or open the flow passage of the fuel from the oil groove to the control chamber, at the same time, with the lifting or falling action of the armature, the armature dynamically opens or closes the flow passage of the control chamber to the first oil channel. When the armature is lifted, the high-pressure fuel no longer enters the control chamber due to the conical surface structure, so that the pressure in the control chamber can be rapidly reduced, the opening time of the needle valve is shortened, and the response performance of the injector is improved. The armature is immersed in the oil groove, which lubricates the outer surface of the armature, and the heat generated by the sliding of the armature in the valve seat hole is taken away by the flowing fuel, thereby achieving the effect of cooling.

[0020] Another object of the utility model is to provide a dual-fuel injector assembly, which can control the fuel control valve and the gas control valve respectively according to the application scene, so as to spray fuel or gas.

[0021] The purpose of this utility model is achieved through such a technical solution, specifically providing a dual-fuel injector assembly, including a control valve structure, which has two sets, namely a fuel control valve and a gas control valve, and also includes a solenoid valve assembly and a needle valve assembly.

[0022] Preferably, the metering valve of the fuel control valve and the metering valve of the gas control valve are integrally formed.

[0023] Due to the adoption of the above technical solution, this utility model has the following advantages: the injector can inject fuel oil or gas, improve the application scenarios, and can quickly start the injection time. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of this utility model, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0025] Figure 1 This is a schematic diagram of the structure of a control valve according to the present invention;

[0026] Figure 2 This is a schematic diagram of the valve seat assembly.

[0027] Figure 3 This is an enlarged schematic diagram of the conical structure (enlarged at point A);

[0028] Figure 4 This is a schematic diagram of the injector body;

[0029] Figure 5 This is a schematic diagram of the dual-fuel injector assembly.

[0030] Figure label:

[0031] 1-Injector body, 11-Control chamber, 12-Return oil passage,

[0032] 2-Valve seat assembly, 21-Valve seat, 211-Valve seat bore, 212-Oil reservoir, 213-Buffer groove, 214-First groove, 22-Armature, 221-Second groove, 23-Fuel inlet passage

[0033] 3-Metering valve, 31-First oil passage, 32-Second metering orifice, 33-First metering orifice, 34-Second oil passage

[0034] 4-Cone structure, 41-Cone surface, 42-Seat surface,

[0035] 5-Fuel control valve, 6-Gas control valve

[0036] 7-Solenoid valve assembly, 71-Solenoid valve seat, 72-Solenoid valve spring,

[0037] 8 - needle valve assembly, 81 - needle valve seat, 82 - needle valve body, 83 - needle valve spring. DETAILED DESCRIPTION

[0038] Referring to Figure 1 , Figure 2 and Figure 4 , a control valve structure includes an injector body 1, a valve seat assembly 2, and a metering valve 3.

[0039] The injector body 1 is provided with a control cavity 11; the valve seat assembly 2 is arranged in the injector body 1 and comprises a valve seat 21 and an armature 22, the valve seat 21 is provided with a valve seat hole 211, and the armature 22 slides along the valve seat hole 211; the valve seat 21 is provided with an oil pool 212 in communication with the valve seat hole 211, fuel enters the control cavity 11 through the oil pool 212, and a conical surface structure 4 is arranged between the oil pool 212 and the control cavity 11; a metering valve 3 is arranged below the valve seat 21, the metering valve 3 is provided with a first oil channel 31, and with the lifting or falling of the armature 22, the conical surface structure 4 closes or opens the flow channel between the oil pool 212 and the control cavity 11, and at the same time, the armature 22 opens or closes the flow channel between the first oil channel 31 and the control cavity 11. Specifically, the valve seat 21 is provided with a fuel inlet channel 23, fuel enters the fuel inlet channel 23 at high pressure, and the fuel enters the oil pool 212 through the fuel inlet channel 23 and then enters the control cavity 11. When the armature 22 is lifted, the conical surface structure 4 closes the flow channel between the oil pool 212 and the control cavity 11, the fuel in the oil pool 212 cannot enter the control cavity 11, and due to the lifting of the armature 22, the end surface of the armature 22 is separated from the end surface of the metering valve 3, the first oil channel 31 is in communication with the control cavity 11, the fuel in the control cavity 11 flows out through the first oil channel 31, at this time, the needle valve overcomes the pressure of the control cavity 11, the needle valve is lifted, and oil injection starts. When the armature 22 is seated, the end surface of the armature 22 is tightly attached to the end surface of the metering valve 3, the first oil channel 31 is closed with the control cavity 11, at this time, the conical surface structure 4 opens the flow channel between the oil pool 212 and the control cavity 11, there is a flow gap, fuel enters the control cavity 11 through the oil pool 212, the pressure difference between the control cavity 11 and the needle valve is reduced, the needle valve falls, and oil injection stops. When the armature 22 is lifted, the high-pressure fuel does not enter the control cavity 11 due to the conical surface structure 4, which can rapidly reduce the pressure in the control cavity 11, shorten the opening time of the needle valve, and improve the response performance of the injector. In the prior art, the armature seals the control cavity, and the control cavity is a high-pressure cavity. The armature is subjected to upward hydraulic pressure and downward spring force, and due to F=PS, the higher the pressure of the fuel, the greater the hydraulic pressure on the armature, and the higher the required spring force, which can seal the fuel. The higher the spring force, the greater the required electromagnetic force, because when the electromagnetic force overcomes the spring force, the armature can be lifted. The armature 22 seals the first oil channel 31 of the low-pressure oil channel, so the spring force for sealing low-pressure oil is smaller than that for sealing high-pressure oil, the required electromagnetic force is smaller, the electromagnetic force is positively related to the size of the electromagnetic valve assembly, which plays an important role in the miniaturization of the electromagnetic valve, and facilitates the miniaturization of the injector.

[0040] See Figure 2 and Figure 3Further, the conical surface structure 4 comprises a conical surface 41 arranged on the armature 22 and a seat surface 42 arranged on the valve seat 21 and matched with the conical surface 41, and the seat surface 42 and the conical surface 41 are preset with an angle. Specifically, the conical surface angle of the armature 22 is smaller than the seat surface angle of the valve seat 21, the angle of the whole conical surface of the armature 22 is 89°, the angle of the whole seat surface of the valve seat 21 is 90°, the preset angle is 0.5°, if the preset angle is greater than 0.5°, the sliding length of the seat surface 42 and the conical surface 41 is relatively long, if the preset angle is less than 0.5°, the flow gap is relatively small, the preset angle is 0.5°, which can improve the response performance of the injector, when the armature 22 moves upward, the seat surface 42 and the conical surface 41 form a linear seal at the port, at this time, the high-pressure fuel in the oil groove 212 cannot enter the control chamber 11, and the high-pressure fuel in the control chamber 11 flows out through the low-pressure first oil channel 31, the pressure in the control chamber 11 decreases, the needle valve is lifted upward, and then the fuel injection is started. The conical surface structure 4 dynamically closes or opens the flow channel with the movement of the armature 22, and plays a role in controlling whether the high-pressure fuel in the oil groove 212 can enter the control chamber 11, thereby improving the response performance of the injector.

[0041] Please refer to Figure 1 , Figure 2 and Figure 5 , further, the injector body 1 is provided with a return oil channel 12, and the upper end surface of the valve seat hole 211 is provided with a first groove 214 in communication with the return oil channel 12; the first groove 214 and the oil groove 212 are in communication. Specifically, the return oil channel 12 is a low-pressure oil channel, the armature 22 is matched with the upper end surface of the valve seat hole 211 in a small gap, and the armature 22 slides up and down in the valve seat hole 211, and the small gap matching has a guiding effect on the sliding of the armature 22. The oil groove 212 is a high-pressure groove, part of the fuel entering from the fuel inlet channel 23 flows into the first groove 214 from the oil groove 212 through the gap, and then flows out from the return oil channel 12. The fuel flows outside the armature 22, and in the flow process, the fuel carries away the heat generated by the friction of the armature 22 in the sliding process in the valve seat hole 211, which has a cooling effect on the fast-moving armature. At the same time, it has a lubricating effect on the lifting or falling movement of the armature 22, reducing the wear of the armature 22 and the valve seat hole 211.

[0042] Please refer to Figure 1 and Figure 2 , further, a buffer groove 213 is arranged in the flow channel between the oil groove 212 and the control chamber 11. The buffer groove 213 buffers the flow stress of the high-pressure fuel and delays the fatigue damage of the flow channel by the high-pressure fuel.

[0043] Please refer to Figure 1 and Figure 2, further, the end surface of the metering valve 3 is provided with a first metering hole 33 and a second metering hole 32, the first metering hole 33 is in communication with the control cavity 11 and the buffer groove 213, and the second metering hole 32 is in communication with the first oil channel 31. Specifically, one end of the first metering hole 33 is in communication with the control cavity 11, and the other end is in communication with the buffer groove 213. The first metering hole 33 and the second metering hole 32 are parallel to each other. When the armature 22 is lifted, the first metering hole 31 and the second metering hole 32 are in communication, and the fuel in the control cavity 11 flows out through the first metering hole 33, the second metering hole 32 and the first oil channel 31. When the armature 22 falls, the second oil channel 32 is closed in communication with the control cavity 11.

[0044] Please refer to Figure 1 and Figure 2 , further, the first metering hole 33 is provided with a second oil channel 34 in the control cavity 11, and the diameter of the second oil channel 34 is greater than that of the first metering hole 33. With this structure, when high-pressure fuel enters the control cavity 11 from the first metering hole 33 or flows from the control cavity 11 to the second metering hole 32, the second oil channel 34 has a buffering effect on the flow stress of high-pressure fuel, delaying the fatigue damage of high-pressure fuel to the metering valve 3 and improving the service life of the metering valve 3.

[0045] Please refer to Figure 1 and Figure 2 , further, the lower end surface of the armature 22 is provided with a second groove 221. The second groove 221 is arranged to reduce the contact area between the lower end surface of the armature 22 and the metering valve 3. Under the condition that the armature 22 is fixed by pressure, reducing the area can increase the pressure per unit area, that is, the pressure of the armature 22 on the metering valve 3 increases, the sealing effect is good, and fuel is not easy to leak. Preferably, the second groove 221 is arranged directly above the second metering hole 32. When the armature 22 is lifted and the fuel in the control cavity 11 flows to the second metering hole 32, the second groove 221 has a buffering effect on the flow stress of fuel from the control cavity 11, delaying the fatigue damage of high-pressure fuel to the metering valve 3 and improving the service life of the metering valve 3.

[0046] Please refer to Figure 4 and Figure 5The double-fuel injector assembly comprises a control valve structure, the control valve structure is provided with two groups of fuel control valves 5 and gas control valves 6, and further comprises an electromagnetic valve assembly 7 and a needle valve assembly 8. Specifically, the electromagnetic valve assembly 7 is provided with two groups of electromagnetic valves corresponding to the fuel control valves 5 and the gas control valves 6 respectively, the electromagnetic valve assembly 7 comprises an electromagnetic valve seat 71 and an electromagnetic valve spring 72, the electromagnetic valve seat 71 is arranged in the injector body 1, the electromagnetic valve spring 72 is arranged in the electromagnetic valve seat 71, one end of the electromagnetic valve spring 72 is in abutment with the electromagnetic valve seat 71, and the other end is in pressure connection with the valve seat assembly 2. The needle valve assembly 8 comprises a needle valve seat 81, a needle valve body 82 and a needle valve spring 83, the needle valve seat 81 is arranged in the injector body 1, the needle valve body 82 and the needle valve spring 83 are arranged in the needle valve seat 81, one end of the needle valve spring 83 is in abutment with the outer surface of the control cavity, and the other end is in abutment with the needle valve body 82.

[0047] The basic working principle of the double-fuel injector assembly is similar to that of the prior art, and the working principle is illustrated by taking the fuel injection control principle as an example: one part of the high-pressure fuel enters the oil tank 212 through the fuel oil channel 23, and then enters the control cavity 11 through the buffer groove 213, the first metering hole 33 and the second oil channel 34. When the electromagnetic valve seat 71 is electrified, the armature 22 lifts up against the pressure of the electromagnetic valve spring 72, the two tapered surfaces of the tapered surface structure 4 have an angle deviation, and the fuel in the oil tank 212 cannot enter the control cavity 11 after being in contact with the line seal. In addition, the first oil channel 31 is in communication with the control cavity 11 due to the lifting of the armature 22, the fuel in the control cavity 11 flows out through the second oil channel 34, the first metering hole 33, the second metering hole 32 and the first oil channel 31, at this time, the pressure difference of the control cavity 11 to the needle valve body 82 overcomes the elastic force of the needle valve spring 83, the needle valve body 82 lifts up, and oil injection starts. When the electromagnetic valve seat 71 is de-energized, the armature 22 falls down, the first oil channel 31 is closed in communication with the control cavity 11, at this time, the tapered surface structure 4 has a communication gap, the fuel enters the control cavity 11, the pressure difference between the control cavity 11 and the needle valve body 82 is reduced, the spring force of the needle valve spring 83 overcomes the hydraulic pressure of the control cavity 11, the needle valve body 82 falls down, and oil injection stops. Similarly, the gas injection control principle is the same.

[0048] Please refer to Figure 1 Further, the metering valve of the fuel control valve 5 and the metering valve of the gas control valve 6 are integrally formed, which is convenient for processing and manufacturing and saves costs.

[0049] The control valve structure and the dual fuel injector assembly, the taper surface structure 4 is arranged in the control valve structure, and the flow channel of fuel from the oil tank 212 to the control cavity 11 is dynamically closed or opened along with the lifting or falling action of the armature 22, simultaneously, the flow channel of the control cavity 11 to the first oil channel 31 is dynamically opened or closed along with the lifting or falling action of the armature 22, when the armature 22 is lifted, the high-pressure fuel does not enter the control cavity 11 due to the taper surface structure 4, the pressure in the control cavity 11 can be rapidly reduced, the needle valve opening time is shortened, and the response performance of the injector is improved. The second oil channel, the second groove 221 and the buffer groove 213 are arranged, the flow stress of the high-pressure fuel has a buffering effect, fatigue damage of the high-pressure fuel to the metering valve 3 and the valve seat 21 is delayed, and the service life of the injector is improved. The first groove 214 in communication with the oil return channel 12 is arranged on the upper end surface of the valve seat hole 211, and the armature 22 moving at high speed also has the effects of cooling, guiding and lubricating. The armature 22 seals the first oil channel 31 of the oil channel, the required electromagnetic force is small, the miniaturization of the electromagnetic valve is important, and the miniaturization of the injector is facilitated.

[0050] The above specific embodiments are used to further explain the purpose, technical scheme and beneficial effects of the utility model, and it should be understood that the above description is only a specific implementation method of the utility model, and is not used to limit the utility model, and any modification, equivalent replacement and improvement within the main idea of the utility model should be included in the protection scope of the utility model.

Claims

1. A control valve structure characterized by comprising: The utility model relates to a control valve structure of fuel injection system, including: The injector body (1) is equipped with control cavity (11); Valve seat assembly (2) is arranged in the injector body (1), including valve seat (21) and armature (22), valve seat (21) is equipped with valve seat hole (211), valve seat (21) is equipped with with oil groove (212) with valve seat hole (211) intercommunication, fuel enters control cavity (11) through with oil groove (212), and with oil groove (212) and control cavity (11) are equipped with taper structure (4) between; Metering valve (3) is arranged below valve seat (21) and is equipped with first oil channel (31); With the lifting or falling of armature (22) along valve seat hole (211), taper structure (4) closes or opens the flow passage of with oil groove (212) and control cavity (11), and simultaneously armature (22) opens or closes the flow passage of first oil channel (31) and control cavity (11).

2. The control valve structure according to claim 1, characterized by Taper structure (4) includes taper (41) arranged on armature (22) and seat surface (42) arranged on valve seat (21) and matched with taper (41), and seat surface (42) and taper (41) are preset an angle.

3. The control valve structure according to claim 2, characterized by The angle is 0.5 °.

4. A control valve arrangement according to claim 1, 2 or 3, characterised in that, The injector body (1) is equipped with oil return channel (12), and the upper end surface of valve seat hole (211) is equipped with first groove (214) communicated with oil return channel (12);First groove (214) and with oil groove (212) are communicated.

5. The control valve structure according to claim 1, 2 or 3, characterized by Buffer groove (213) is arranged in the flow passage of with oil groove (212) and control cavity (11).

6. The control valve structure according to claim 5, characterized by The end surface of metering valve (3) is equipped with first metering hole (33) and second metering hole (32), first metering hole (33) is communicated with control cavity (11) and buffer groove (213), and second metering hole (32) is communicated with first oil channel (31).

7. The control valve structure according to claim 6, characterized by First metering hole (33) and control cavity (11) are equipped with second oil channel (34), and the diameter of second oil channel (34) is greater than the diameter of first metering hole (33).

8. A control valve structure according to claim 1, 2, 3, 6 or 7, characterised in that The lower end surface of armature (22) is equipped with second groove (221).

9. A dual fuel injector assembly characterized by, The utility model relates to a control valve structure of fuel injection system, including:

10. The dual fuel injector assembly of claim 9, wherein, The metering valve of fuel control valve (5) and the metering valve of gas control valve (6) are integrally formed.

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