A dual fuel injector, an engine and a control method of a dual fuel injector

Abstract

The application relates to the engine technical field, and particularly discloses a dual-fuel injector, an engine and a control method of the dual-fuel injector, which comprises a fuel supply channel, a gas supply channel and a fuel injection part. The fuel supply channel is used for conveying fuel, the gas supply channel is used for conveying gas, the fuel injection part is used for being communicated with a combustion chamber, the fuel injection part can be selectively communicated with the fuel supply channel, and the fuel injection part can also be selectively communicated with the gas supply channel, so that the fuel and the gas are both injected into the combustion chamber through the fuel injection part. When the gas passes through the fuel injection part, the fuel in the fuel injection part can be flushed to be brought into the combustion chamber to improve the fuel utilization rate of the fuel, the fuel injection part is prevented from storing fuel and carbonizing, the thermal efficiency and the emission of the engine are ensured, and in addition, the gas and the fuel are both injected into the combustion chamber through the fuel injection part, the atomization effect and the ignition effect of diesel oil can be ensured.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and in particular to a dual-fuel injector, an engine, and a control method for the dual-fuel injector. Background Technology

[0002] Existing engines may use a single fuel or a dual fuel. Taking a dual-fuel engine as an example, the fuel supply method of a dual-fuel engine is to directly inject gas (such as natural gas) into the combustion chamber through a dual-fuel injector, and use a ignition amount of liquid fuel (such as diesel) to trigger the combustion of the gaseous fuel, thereby driving the engine to run. This can effectively improve the engine's power, economy and emissions.

[0003] Existing dual-fuel injectors, such as the one disclosed in the earlier patent application CN202020447532.0, include an injector body, a jet needle valve, and an injection valve needle. The injector body has a first injection section (for injecting natural gas) and a second injection section (for injecting diesel fuel). The jet needle valve is used to close or open the first injection section, and the injection valve needle is used to close or open the second injection section. This injector has the following problems:

[0004] 1) Diesel and natural gas injections are independent of each other. Due to the current level of injection technology, the injection rail pressure of diesel is relatively low. In order to avoid diesel being injected onto the bottom surface of the cylinder head, the injector extends into the combustion chamber in a larger size. At high temperatures, diesel is prone to coking and carbon deposits. After the engine has been running for a long time, the holes of the second injection section become blocked, resulting in poor combustion, thermal efficiency and emissions deterioration.

[0005] 2) The two-row design with the first and second injection sections spaced apart results in a large distance between the natural gas and the diesel flame after it is injected. Furthermore, due to the low injection rail pressure of the diesel, the atomization effect of the diesel is poor, which leads to a poor ignition effect.

[0006] Therefore, there is an urgent need for a dual-fuel injector and engine to solve the above problems. Summary of the Invention

[0007] The purpose of this invention is to provide a dual-fuel injector, an engine, and a control method for the dual-fuel injector, in order to solve the problem that carbon deposits easily form in the nozzles of existing dual-fuel injectors, affecting engine performance.

[0008] In a first aspect, the present invention provides a dual-fuel injector, the dual-fuel injector comprising:

[0009] The dual-fuel injector includes a fuel supply channel and a gas supply channel, wherein the fuel supply channel is used to transport fuel and the gas supply channel is used to transport gas. The dual-fuel injector further includes a fuel injection section, which is connected to a combustion chamber. The fuel injection section is selectively connected to the fuel supply channel and also selectively connected to the gas supply channel.

[0010] As a preferred technical solution for a dual-fuel injector, the fuel injection section includes a flow stabilizing chamber and a fuel injection orifice. The flow stabilizing chamber can selectively communicate with the fuel supply channel and can also selectively communicate with the gas supply channel. The flow stabilizing chamber is connected to one end of the fuel injection orifice, and the other end of the fuel injection orifice is used to communicate with the combustion chamber.

[0011] As a preferred technical solution for a dual-fuel injector, the flow stabilizing chamber includes a first flow stabilizing chamber, a second flow stabilizing chamber, and an injection hole connecting the first flow stabilizing chamber and the second flow stabilizing chamber. The first flow stabilizing chamber is selectively connected to the fuel supply channel, and the second flow stabilizing chamber is selectively connected to the gas supply channel. The second flow stabilizing chamber surrounds the outer periphery of the first flow stabilizing chamber, and the centerline of the second flow stabilizing chamber coincides with the centerline of the first flow stabilizing chamber.

[0012] As a preferred technical solution for a dual-fuel injector, the injection port is horizontally opened and located above the fuel injection port.

[0013] As a preferred technical solution for a dual-fuel injector, the dual-fuel injector includes a plurality of fuel injection holes, which are uniformly distributed along the circumference of the second flow stabilizing cavity;

[0014] The flow stabilizing cavity includes a plurality of injection holes, which are evenly distributed along the circumference of the first flow stabilizing cavity.

[0015] As a preferred technical solution for a dual-fuel injector, the injection holes are located near the top of the second flow stabilizing chamber and far from the bottom of the second flow stabilizing chamber, and the coverage of the fuel injected by the multiple injection holes can cover the entire cavity wall of the second flow stabilizing chamber.

[0016] As a preferred technical solution for a dual-fuel injector, the dual-fuel injector includes a first valve body, a second valve body, and a housing. The second valve body is slidably disposed within the housing, and the first valve body is slidably disposed within the second valve body. The inner surfaces of the second valve body and the housing form a gas supply channel, and the first valve body and the second valve body form a fuel supply channel.

[0017] The first flow stabilizing chamber is disposed in the second valve body, and the first flow stabilizing chamber and the fuel supply channel are connected through the first opening. The first valve body can slide relative to the second valve body and has a first open position and a first closed position. When the first valve body is in the first closed position, the first valve body closes the first opening. When the first valve body is in the first open position, the first valve body opens the first opening.

[0018] The second flow stabilizing chamber is disposed in the outer shell, and the second flow stabilizing chamber and the gas supply channel are connected through the second opening. The second valve body can slide relative to the outer shell and has a second open position and a second closed position. When the second valve body is in the second closed position, the second valve body closes the second opening; when the second valve body is in the second open position, the second valve body opens the second opening.

[0019] As a preferred technical solution for dual-fuel injectors, the bottom surface of the cylinder head is located between the fuel injection hole and the oil injection hole.

[0020] The dual-fuel injector provided by this invention has at least the following beneficial effects:

[0021] This dual-fuel injector includes a fuel supply passage, a gas supply passage, and a fuel injection section. The fuel supply passage delivers fuel, the gas supply passage delivers gas, and the fuel injection section communicates with the combustion chamber. The fuel injection section can selectively communicate with both the fuel and gas supply passages. In this dual-fuel injector, both fuel and gas are injected into the combustion chamber through the fuel injection section. When the gas passes through the fuel injection section, it flushes the fuel within, carrying it into the combustion chamber for combustion, improving fuel utilization, preventing fuel residue in the fuel injection section, and thus preventing fuel carbonization within the fuel injection section, ensuring engine thermal efficiency and emissions. Furthermore, the simultaneous injection of both fuel and gas into the combustion chamber through the fuel injection section ensures effective atomization and ignition of the diesel fuel.

[0022] Secondly, the present invention provides an engine including a dual-fuel injector as described in any of the above embodiments. The engine further includes a cylinder block, a cylinder head, and a piston. The piston is slidably located within the cylinder block, and the cylinder head covers the cylinder block. When the piston reaches top dead center, a combustion chamber is formed between the top surface of the piston and the bottom surface of the cylinder head. The dual-fuel injector passes through the cylinder head, and the bottom end of the dual-fuel injector extends into the combustion chamber. The fuel injection portion communicates with the combustion chamber.

[0023] The engine provided by this invention has at least the following beneficial effects:

[0024] The engine includes the aforementioned dual-fuel injector, a cylinder block, a cylinder head, and a piston. The piston slides within the cylinder block, and the cylinder head covers the cylinder block. When the piston reaches top dead center, a combustion chamber is formed between the top surface of the piston and the bottom surface of the cylinder head. The dual-fuel injector passes through the cylinder head, with its bottom end extending into the combustion chamber, and the fuel injection section communicates with the combustion chamber. This engine employs the aforementioned dual-fuel injector, which effectively prevents fuel carbonization and coking, ensuring the reliability and stability of engine operation.

[0025] Thirdly, the present invention provides a control method for a dual-fuel injector, implemented by a dual-fuel injector in any of the above-mentioned schemes. The control method for the dual-fuel injector includes a fuel priority injection control method, a gas priority injection method, and a dual-fuel synchronous injection control method.

[0026] The fuel priority injection control method includes: first connecting the fuel supply channel to the fuel injection unit and disconnecting the gas supply channel from the fuel injection unit, with the fuel injection unit injecting fuel into the combustion chamber; then disconnecting the fuel supply channel from the fuel injection unit and connecting the gas supply channel to the fuel injection unit, with the fuel injection unit injecting gas into the combustion chamber.

[0027] The gas priority injection control method includes: first disconnecting the fuel supply channel from the fuel injection unit and connecting the gas supply channel to the fuel injection unit, with the fuel injection unit injecting gas into the combustion chamber; then connecting the fuel supply channel to the fuel injection unit and disconnecting the gas supply channel from the fuel injection unit, with the fuel injection unit injecting fuel into the combustion chamber.

[0028] The dual-fuel synchronous injection control method includes: first connecting the fuel supply channel to the fuel injection unit and the gas supply channel to the fuel injection unit, wherein the fuel injection unit simultaneously injects gas and fuel into the combustion chamber; then disconnecting the fuel supply channel from the fuel injection unit and the gas supply channel from the fuel injection unit.

[0029] The control method for dual-fuel injectors provided by this invention has at least the following beneficial effects:

[0030] The control methods for this dual-fuel injector include fuel-priority injection control, gas-priority injection control, and dual-fuel synchronous injection control. In the fuel-priority injection control method, fuel is injected before gas. Some of the first-injected fuel remains in the fuel injection nozzle. The subsequently injected gas flushes this remaining fuel into the combustion chamber, preventing carbonization and coking, and improving fuel utilization. In the gas-priority injection method, gas is injected before fuel. Some of the first-injected gas remains in the fuel injection nozzle. The subsequently injected fuel carries this remaining fuel into the combustion chamber, improving gas utilization. In the synchronous injection control method, fuel and gas are injected simultaneously. Because the gas injection rail pressure is greater than the fuel injection rail pressure, the fuel entering the fuel injection nozzle shares the gas injection rail pressure, resulting in more complete atomization after being injected into the combustion chamber. Furthermore, fuel and gas are injected into the combustion chamber simultaneously from the same fuel injection orifice, achieving optimal fuel ignition. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the first structure of the dual-fuel injector in an embodiment of the present invention (the first valve body is located in the first closed position, and the second valve body is located in the second closed position);

[0032] Figure 2 This is a schematic diagram of the second structure of the dual-fuel injector in an embodiment of the present invention (the first valve body is located in the first open position, and the second valve body is located in the second closed position);

[0033] Figure 3 This is a schematic diagram of the third structure of the dual-fuel injector in an embodiment of the present invention (the first valve body is located in the first closed position, and the second valve body is located in the second open position);

[0034] Figure 4 This is a schematic diagram of the fourth structure of the dual-fuel injector in an embodiment of the present invention (the first valve body is located in the first open position, and the second valve body is located in the second open position).

[0035] In the picture:

[0036] 1. Fuel oil supply channel; 2. Gas supply channel;

[0037] 3. Fuel injection section; 31. Fuel injection orifice; 32. Flow stabilizing chamber; 321. First flow stabilizing chamber; 322. Second flow stabilizing chamber; 323. Fuel injection orifice;

[0038] 4. First opening; 5. Second opening;

[0039] 10. First valve body; 20. Second valve body; 30. Outer shell. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] Existing injectors include an injector body, a jet needle valve, and an injection valve needle. The injector body has a first injection section and a second injection section. The jet needle valve is used to close or open the first injection section, and the injection valve needle is used to close or open the second injection section. In this injector, diesel and natural gas injections are independent. Due to current injection technology limitations, the diesel injection rail pressure is relatively low. Furthermore, to avoid diesel being injected onto the bottom surface of the cylinder head, the injector extends a relatively large area into the combustion chamber. At high temperatures, diesel is prone to coking and carbon deposits. After prolonged engine operation, this can cause blockage of the second injection section's orifices, resulting in poor combustion, deteriorating thermal efficiency, and emissions. Additionally, the two-row design with the first and second injection sections spaced apart results in a larger distance between the natural gas and diesel flame after injection. Furthermore, due to the lower diesel injection rail pressure, diesel atomization is poor, leading to poor ignition.

[0045] In response, this embodiment provides a dual-fuel injector to solve the above-mentioned problems.

[0046] Please refer to Figures 1 to 4 This dual-fuel injector includes a fuel supply passage 1, a gas supply passage 2, and a fuel injection section 3. The fuel supply passage 1 delivers fuel (such as diesel), the gas supply passage 2 delivers gas (such as natural gas), and the fuel injection section 3 communicates with the combustion chamber. The fuel injection section 3 can selectively communicate with the fuel supply passage 1 and also selectively communicate with the gas supply passage 2. With this configuration, both fuel and gas are injected into the combustion chamber through the fuel injection section 3. When the gas passes through the fuel injection section 3, it flushes the fuel within, carrying it into the combustion chamber for combustion, improving fuel utilization, preventing fuel accumulation in the fuel injection section 3, and thus preventing fuel carbonization within the fuel injection section 3, ensuring engine thermal efficiency and emissions. Furthermore, since both gas and fuel are injected into the combustion chamber through the fuel injection section 3 without any gaps, it ensures effective atomization and ignition of the diesel fuel.

[0047] It should be noted that natural gas does not coke at high temperatures, and therefore will not cause carbon buildup inside the fuel injection section 3.

[0048] Optionally, the fuel injection unit 3 includes a flow stabilizing chamber 32 and a fuel injection orifice 31. The flow stabilizing chamber 32 can be selectively connected to the fuel supply channel 1 and also selectively connected to the gas supply channel 2. One end of the flow stabilizing chamber 32 is connected to the fuel injection orifice 31, and the other end of the fuel injection orifice 31 is used to connect to the combustion chamber. After the fuel and gas enter the flow stabilizing chamber 32, the flow rate of the fuel and gas entering the fuel injection orifice 31 can be stabilized by the flow stabilizing chamber 32, thereby ensuring that the fuel and gas are injected into the combustion chamber at a stable flow rate, ensuring complete combustion. In addition, by stabilizing the flow rate of the gas through the flow stabilizing chamber 32, it can be ensured that the gas flushes the fuel in the fuel injection orifice 31 at a stable flow rate, ensuring a stable flushing effect.

[0049] Optionally, the flow stabilizing chamber 32 includes a first flow stabilizing chamber 321, a second flow stabilizing chamber 322, and an injection port 323 connecting the first flow stabilizing chamber 321 and the second flow stabilizing chamber 322. The first flow stabilizing chamber 321 is selectively connected to the fuel supply channel 1, and the second flow stabilizing chamber 322 is selectively connected to the gas supply channel 2. The second flow stabilizing chamber 322 surrounds the outer periphery of the first flow stabilizing chamber 321, and the center line of the second flow stabilizing chamber 322 coincides with the center line of the first flow stabilizing chamber 321. This configuration serves several purposes. First, after the fuel is stabilized in the first flow stabilizing chamber 321, it enters the second flow stabilizing chamber 322 at a stable flow rate, where it is further stabilized to ensure a stable flow. Second, the first flow stabilizing chamber 321 isolates the fuel, preventing combustion gases from mixing into the fuel supply channel 1. Third, when fuel is injected into the combustion chamber, if fuel is injected before combustion gases, the combustion gases can flush the fuel in the second flow stabilizing chamber 322 and the fuel injection orifice 31, preventing carbonization and coking of the fuel in these areas. If fuel is injected after combustion gases, the fuel can carry the combustion gases remaining in the second flow stabilizing chamber 322 into the combustion chamber, ensuring efficient fuel utilization. When fuel and combustion gases are injected simultaneously, the fuel entering the second flow stabilizing chamber 322 mixes thoroughly with the combustion gases, improving the uniformity of the mixture and thus enhancing the ignition effect.

[0050] It should be noted that when fuel is injected into the combustion chamber, if the fuel is injected after the gas, the gas injected in the second injection can flush the fuel remaining in the second flow stabilizing chamber 322 and the fuel injection hole 31 from the previous injection, thus preventing the fuel from carbonizing and coking in the second flow stabilizing chamber 322 and the fuel injection hole 31. Similarly, if the fuel is injected before the gas, the fuel injected in the second injection can carry the gas remaining in the second flow stabilizing chamber 322 and the fuel injection hole 31 from the previous injection into the combustion chamber.

[0051] In addition, the injection rail pressure of the gas is greater than that of the fuel injection rail. When fuel and gas are injected simultaneously, the fuel enters the second flow stabilizing chamber 322 and shares the injection pressure of the gas, thereby improving the atomization effect and the ignition effect.

[0052] Optionally, the flow stabilizing chamber 32 includes a plurality of injection holes 323, which are evenly distributed circumferentially along the first flow stabilizing chamber 321. This ensures that fuel is evenly injected into the second flow stabilizing chamber 322. In this embodiment, the first flow stabilizing chamber 321 is hemispherical.

[0053] Optionally, the dual-fuel injector includes multiple fuel injection holes 31, which are evenly distributed circumferentially along the second flow stabilizing chamber 322 to ensure that the fuel gas and fuel oil are evenly injected into the combustion chamber. In this embodiment, the second flow stabilizing chamber 322 is hemispherical.

[0054] Optionally, the bottom surface of the cylinder head is located between the fuel injection port 31 and the fuel injection port 323. The bottom surface of the cylinder head is as follows: Figure 1 As shown in S, the distance between the bottom surface of the cylinder head and the bottom end of the fuel injection hole 31 is H. Compared with the existing dual-fuel injector, which requires the injection parts for injecting fuel and gas to be arranged in the combustion chamber at the same time, in this embodiment, since both fuel and gas are injected into the combustion chamber through the same gas injection hole, the value of H can be effectively reduced compared with the existing technology. This reduces the contact area between the dual-fuel injector and the high-temperature gas in the combustion chamber, lowers the temperature of the dual-fuel injector, and prevents the fuel from carbonizing and coking in the dual-fuel injector.

[0055] Optionally, the fuel injection port 323 is horizontally positioned and located above the fuel injection port 31. With this configuration, after the fuel enters the second flow stabilizing chamber 322, the combustion gas in the second flow stabilizing chamber 322 can be carried into the combustion chamber from top to bottom.

[0056] Optionally, the fuel injection port 31 is inclined downward, that is, the injection direction of the fuel injection port 31 is set at an angle to the vertical plane. Specifically, the angle between the injection direction of the fuel injection port 31 and the vertical plane can be determined by the shape of the combustion chamber.

[0057] Optionally, the fuel injection holes 323 are located near the top of the second flow stabilizing chamber 322 and far from its bottom, and the fuel injected by the multiple fuel injection holes 323 can cover the entire wall of the second flow stabilizing chamber 322. This arrangement ensures that after the fuel enters the second flow stabilizing chamber 322, it can carry the combustion gas from top to bottom into the combustion chamber, thus significantly improving the combustion efficiency of the combustion gas.

[0058] Optionally, the dual-fuel injector includes a first valve body 10, a second valve body 20, and a housing 30. The second valve body 20 is slidably disposed within the housing 30, and the first valve body 10 is slidably disposed within the second valve body 20. A gas supply channel 2 is formed between the inner surfaces of the second valve body 20 and the housing 30, and a fuel supply channel 1 is formed between the first valve body 10 and the second valve body 20.

[0059] The first flow stabilizing chamber 321 is disposed in the second valve body 20, and the first flow stabilizing chamber 321 and the fuel supply channel 1 are connected through the first opening 4. The first valve body 10 can slide relative to the second valve body 20 and has a first open position and a first closed position, such as... Figure 1 and Figure 3 As shown, when the first valve body 10 is in the first closed position, the first valve body 10 closes the first opening 4, at which time the fuel supply channel 1 cannot supply fuel to the first flow stabilizing chamber 321; as Figure 2 and Figure 4 As shown, when the first valve body 10 is in the first open position, the first valve body 10 opens the first opening 4, at which time the fuel supplied by the fuel supply channel 1 can enter the first flow stabilizing chamber 321 through the first opening 4. Specifically, in this embodiment, when the first valve body 10 is in the first closed position, the first valve body 10 partially extends into the first flow stabilizing chamber 321 and is sealed against the edge of the first opening 4, thereby separating the fuel supply channel 1 and the first flow stabilizing chamber 321.

[0060] The second flow stabilizing chamber 322 is disposed on the outer casing 30, and the second flow stabilizing chamber 322 and the gas supply channel 2 are connected through the second opening 5. The second valve body 20 can slide relative to the outer casing 30 and has a second open position and a second closed position, such as... Figure 1 and Figure 2 As shown, when the second valve body 20 is in the second closed position, the second valve body 20 closes the second opening 5, and at this time, the gas supplied by the gas supply channel 2 cannot enter the second flow stabilizing chamber 322 through the second opening 5; as Figure 3 and Figure 4 As shown, when the second valve body 20 is in the second open position, the second valve body 20 opens the second opening 5, at which time the gas supplied by the gas supply channel 2 can enter the second flow stabilizing chamber 322 through the second opening 5. Specifically, in this embodiment, when the second valve body 20 is in the second closed position, the second valve body 20 partially extends into the second flow stabilizing chamber 322 and is sealed against the edge of the second opening 5, thereby separating the gas supply channel 2 and the second flow stabilizing chamber 322.

[0061] Optionally, when the second valve body 20 opens the second opening 5, the fuel injection hole 323 is flush with the top of the second flow stabilizing chamber 322 to ensure the fuel's carrying effect on the combustion gas in the second flow stabilizing chamber 322.

[0062] This embodiment also provides an engine including the aforementioned dual-fuel injector. The engine further includes a cylinder block, a cylinder head, and a piston. The piston slides within the cylinder block, and the cylinder head covers the cylinder block. When the piston reaches top dead center (TDC), a combustion chamber is formed between the top surface of the piston and the bottom surface of the cylinder head. The dual-fuel injector passes through the cylinder head, with its bottom end extending into the combustion chamber. The fuel injection section 3 communicates with the combustion chamber. The position where the piston reaches its highest point within the cylinder block is called TDC, at which point the piston's top surface is furthest from the crankshaft's rotation center. This engine, employing the aforementioned dual-fuel injector, effectively avoids fuel carbonization and coking in the dual-fuel injector, ensuring the engine's reliability and stability.

[0063] This embodiment also provides a control method for a dual-fuel injector, which is implemented using the aforementioned dual-fuel injector.

[0064] Specifically, the control methods for dual-fuel injectors include fuel-priority injection control method, gas-priority injection method, and dual-fuel synchronous injection control method.

[0065] The fuel priority injection control method includes: first, connecting the fuel supply channel 1 to the fuel injection unit 3, and disconnecting the gas supply channel 2 from the fuel injection unit 3; the fuel injection unit 3 then injects fuel into the combustion chamber; then, disconnecting the fuel supply channel 1 from the fuel injection unit 3, and connecting the gas supply channel 2 to the fuel injection unit 3; the fuel injection unit 3 then injects gas into the combustion chamber. For details, please refer to... Figure 1 Before fuel needs to be injected into the combustion chamber, the first valve body 10 is in the first closed position and the second valve body 20 is in the second closed position. At this time, both the fuel supply passage 1 and the gas supply passage 2 are disconnected from the fuel injection unit 3; then refer to Figure 2 This switches the first valve body 10 to the first open position, while the second valve body 20 remains in the second closed position. Only the fuel supply passage 1 and the fuel injection section 3 are connected. The fuel supplied by the fuel supply passage 1 enters the first flow stabilizing chamber 321 through the first opening 4, then enters the second flow stabilizing chamber 322 through the injection hole 323, and is then injected into the combustion chamber through the fuel injection hole 31. After the fuel injection time is reached, then... Figure 3 This switches the first valve body 10 to the first closed position and the second valve body 20 to the second open position, with only the gas supply channel 2 and the fuel injection section 3 connected. The gas supplied by the gas supply channel 2 enters the second flow stabilizing chamber 322 through the second opening 5, and is then injected into the combustion chamber through the fuel injection hole 31. When the gas injection time is reached, please refer to... Figure 1The first valve body 10 remains in the first closed position, while the second valve body 20 switches to the second closed position. In this fuel priority injection control method, some of the fuel injected first will remain in the wall of the second flow stabilizing chamber 322 and the fuel injection hole 31. The fuel injected later can flush the fuel remaining in the wall of the second flow stabilizing chamber 322 and the fuel injection hole 31 into the combustion chamber to avoid fuel carbonization and coking, and improve fuel utilization. In two adjacent injection processes, the fuel injected later can carry the fuel remaining in the second flow stabilizing chamber 322 and the fuel injection hole 31 after the first injection into the combustion chamber to improve fuel utilization.

[0066] The gas priority injection control method includes: first, disconnecting the fuel supply channel 1 from the fuel injection unit 3, and connecting the gas supply channel 2 to the fuel injection unit 3, with the fuel injection unit 3 injecting gas into the combustion chamber; then, connecting the fuel supply channel 1 to the fuel injection unit 3, and disconnecting the gas supply channel 2 from the fuel injection unit 3, with the fuel injection unit 3 injecting fuel into the combustion chamber. For details, please refer to... Figure 1 Before fuel needs to be injected into the combustion chamber, the first valve body 10 is in the first closed position and the second valve body 20 is in the second closed position. At this time, both the fuel supply passage 1 and the gas supply passage 2 are disconnected from the fuel injection unit 3; then refer to Figure 3 Only the gas supply channel 2 and the fuel injection section 3 are connected. The gas supplied by the gas supply channel 2 enters the second flow stabilizing chamber 322 through the second opening 5, and is then injected into the combustion chamber through the fuel injection hole 31. When the gas injection time is reached, then... Figure 2 This switches the first valve body 10 to the first open position and the second valve body 20 to the second closed position, with only the fuel supply passage 1 and the fuel injection section 3 connected. Fuel supplied by the fuel supply passage 1 enters the first flow stabilizing chamber 321 through the first opening 4, then enters the second flow stabilizing chamber 322 through the injection hole 323, and is then injected into the combustion chamber through the fuel injection hole 31. After the fuel injection time is reached, refer to... Figure 1 This switches the first valve body 10 to the first closed position, while the second valve body 20 remains in the second closed position. In the gas priority injection control method, some of the gas injected first will remain in the second flow stabilizing chamber 322 and the fuel injection hole 31. The fuel injected later can carry the fuel remaining in the second flow stabilizing chamber 322 and the fuel injection hole 31 into the combustion chamber to improve the utilization rate of the gas. In two adjacent injection processes, the gas injected later can flush the fuel remaining in the second flow stabilizing chamber 322 and the fuel injection hole 31 after the first injection into the combustion chamber to avoid fuel carbonization and coking.

[0067] The dual-fuel synchronous injection control method includes: first, connecting the fuel supply channel 1 to the fuel injection unit 3, and connecting the gas supply channel 2 to the fuel injection unit 3; the fuel injection unit 3 simultaneously injects gas and fuel into the combustion chamber; then, disconnecting the fuel supply channel 1 from the fuel injection unit 3, and disconnecting the gas supply channel 2 from the fuel injection unit 3. For details, please refer to... Figure 1 Before fuel needs to be injected into the combustion chamber, the first valve body 10 is in the first closed position and the second valve body 20 is in the second closed position. At this time, both the fuel supply passage 1 and the gas supply passage 2 are disconnected from the fuel injection unit 3; then refer to Figure 4 Both the fuel supply channel 1 and the gas supply channel 2 are connected to the fuel injection unit 3. Fuel supplied by the fuel supply channel 1 enters the first flow stabilizing chamber 321 through the first opening 4, and then enters the second flow stabilizing chamber 322 through the injection hole 323. Gas supplied by the gas supply channel 2 enters the second flow stabilizing chamber 322 through the second opening 5. The gas and fuel are fully mixed in the second flow stabilizing chamber 322 and are jointly injected into the combustion chamber through the fuel injection hole 31. Because the gas injection rail pressure is greater than the fuel injection rail pressure, the fuel entering the second flow stabilizing chamber 322 shares the gas injection rail pressure, resulting in more complete atomization after being injected into the combustion chamber. Furthermore, the fuel and gas are simultaneously injected into the combustion chamber from the same fuel injection hole 31, achieving optimal ignition effect. When the injection time for both gas and fuel is reached, refer to... Figure 1 This causes the first valve body 10 to switch to the first closed position and the second valve body 20 to switch to the second closed position, thus disconnecting the fuel supply channel 1 and the gas supply channel 2 from the fuel injection unit 3.

[0068] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A dual-fuel injector, comprising a fuel supply passage (1) and a gas supply passage (2), wherein the fuel supply passage (1) is used to deliver fuel, and the gas supply passage (2) is used to deliver gas, characterized in that, The dual-fuel injector also includes a fuel injection section (3), which is used to communicate with the combustion chamber. The fuel injection section (3) can selectively communicate with the fuel supply channel (1) and can also selectively communicate with the gas supply channel (2). The fuel injection unit (3) includes a flow stabilizing chamber (32) and a fuel injection hole (31). The flow stabilizing chamber (32) can be selectively connected to the fuel supply channel (1) and can also be selectively connected to the gas supply channel (2). One end of the flow stabilizing chamber (32) is connected to the fuel injection hole (31), and the other end of the fuel injection hole (31) is used to connect to the combustion chamber. The flow stabilizing chamber (32) includes a first flow stabilizing chamber (321), a second flow stabilizing chamber (322), and an injection port (323) connecting the first flow stabilizing chamber (321) and the second flow stabilizing chamber (322). The first flow stabilizing chamber (321) is selectively connected to the fuel supply channel (1), and the second flow stabilizing chamber (322) is selectively connected to the gas supply channel (2). The second flow stabilizing chamber (322) surrounds the outer periphery of the first flow stabilizing chamber (321), and the centerline of the second flow stabilizing chamber (322) coincides with the centerline of the first flow stabilizing chamber (321). The fuel injection hole (323) is horizontally opened and is located above the fuel injection hole (31); The flow stabilizing cavity (32) includes a plurality of oil injection holes (323), which are evenly distributed along the circumference of the first flow stabilizing cavity (321); The fuel injection hole (323) is close to the top of the second flow stabilizing cavity (322) and far from the bottom of the second flow stabilizing cavity (322), and the fuel injected by the plurality of fuel injection holes (323) can cover the entire cavity wall of the second flow stabilizing cavity (322).

2. The dual-fuel injector according to claim 1, characterized in that, The dual-fuel injector includes a plurality of fuel injection holes (31), which are uniformly distributed circumferentially along the second flow stabilizing chamber (322).

3. The dual-fuel injector according to claim 1, characterized in that, The dual-fuel injector includes a first valve body (10), a second valve body (20), and a housing (30). The second valve body (20) is slidably disposed within the housing (30), and the first valve body (10) is slidably disposed within the second valve body (20). The inner surfaces of the second valve body (20) and the housing (30) form the gas supply channel (2), and the first valve body (10) and the second valve body (20) form the fuel supply channel (1). The first flow stabilizing chamber (321) is disposed on the second valve body (20), and the first flow stabilizing chamber (321) and the fuel supply channel (1) are connected through the first opening (4). The first valve body (10) can slide relative to the second valve body (20) and has a first open position and a first closed position. When the first valve body (10) is in the first closed position, the first valve body (10) closes the first opening (4). When the first valve body (10) is in the first open position, the first valve body (10) opens the first opening (4). The second flow stabilizing chamber (322) is disposed on the outer shell (30), and the second flow stabilizing chamber (322) and the gas supply channel (2) are connected through the second opening (5). The second valve body (20) can slide relative to the outer shell (30) and has a second open position and a second closed position. When the second valve body (20) is in the second closed position, the second valve body (20) closes the second opening (5); when the second valve body (20) is in the second open position, the second valve body (20) opens the second opening (5).

4. The dual-fuel injector according to any one of claims 1-3, characterized in that, The bottom surface of the cylinder head is located between the fuel injection port (31) and the fuel injection port (323).

5. An engine, characterized in that, The engine includes the dual-fuel injector as described in any one of claims 1-4, and further includes a cylinder block, a cylinder head, and a piston. The piston is slidably located within the cylinder block, and the cylinder head covers the cylinder block. When the piston reaches top dead center, a combustion chamber is formed between the top surface of the piston and the bottom surface of the cylinder head. The dual-fuel injector passes through the cylinder head, and the bottom end of the dual-fuel injector extends into the combustion chamber. The fuel injection section (3) communicates with the combustion chamber.

6. A control method for a dual-fuel injector, characterized in that, The dual-fuel injector described in any one of claims 1-4 is used to implement a dual-fuel injector, wherein the control method of the dual-fuel injector includes a fuel priority injection control method, a gas priority injection control method, and a dual-fuel synchronous injection control method. The fuel priority injection control method includes: first connecting the fuel supply channel (1) to the fuel injection unit (3) and disconnecting the gas supply channel (2) from the fuel injection unit (3), the fuel injection unit (3) injecting fuel into the combustion chamber; then disconnecting the fuel supply channel (1) from the fuel injection unit (3) and connecting the gas supply channel (2) to the fuel injection unit (3), the fuel injection unit (3) injecting gas into the combustion chamber; The gas priority injection control method includes: first disconnecting the fuel supply channel (1) from the fuel injection unit (3) and connecting the gas supply channel (2) to the fuel injection unit (3), with the fuel injection unit (3) injecting gas into the combustion chamber; then connecting the fuel supply channel (1) to the fuel injection unit (3) and disconnecting the gas supply channel (2) from the fuel injection unit (3), with the fuel injection unit (3) injecting fuel into the combustion chamber. The dual-fuel synchronous injection control method includes: first connecting the fuel supply channel (1) to the fuel injection unit (3) and connecting the gas supply channel (2) to the fuel injection unit (3), wherein the fuel injection unit (3) simultaneously injects gas and fuel into the combustion chamber; then disconnecting the fuel supply channel (1) from the fuel injection unit (3) and disconnecting the gas supply channel (2) from the fuel injection unit (3).

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