fuel injector

Abstract

This invention discloses a fuel injector, including an electromagnet, a moving component, and a limiting component. The moving component includes a valve stem, a attracted component, and a valve core. The limiting component includes a first limiting part, a second limiting part, a first elastic part, and a magnetic component located between the first and second limiting parts. The moving component can move between a first position, a second position, and a third position. When in the first position, the electromagnet is de-energized, the attracted component separates from the magnetic component, and the valve core abuts against the valve seat. When in the second position, the electromagnet and the magnetic component have the same magnetism, the magnetic component abuts against the second limiting part, the attracted component abuts against the magnetic component, and the valve core and valve seat have a first gap. When in the third position, the electromagnet and the magnetic component have opposite magnetism, the magnetic component abuts against the first limiting part, the attracted component abuts against the magnetic component, and the valve core and valve seat have a second gap. The second gap is larger than the first gap. This allows for adjustment of the fuel injection quantity of the fuel injector.

Description

Technical Field

[0001] This invention belongs to the field of vehicle fuel injection technology, and specifically relates to a fuel injector. Background Technology

[0002] The engine is the primary power unit of a vehicle. Fuel injected into the cylinders by the injectors mixes with air drawn in from the intake system, resulting in a vigorous combustion reaction. The generated high-temperature, high-pressure gases push the piston up and down, ultimately converting this into rotational mechanical energy output via the crankshaft and connecting rod mechanism. The fuel injection characteristics of the injectors have a crucial impact on the quality of the air-fuel mixture, which in turn directly affects the completeness of gasoline combustion, thus influencing the engine's fuel consumption and emissions. In recent years, to achieve energy conservation and emission reduction, various new engine combustion technologies have been continuously developed, including stratified lean combustion technology. Stratified lean combustion uses excess air to ensure complete fuel combustion, thus possessing significant fuel-saving potential.

[0003] To ensure reliable ignition of the lean air-fuel mixture, a small amount of fuel needs to be injected at the end of the compression stroke to maintain a suitable mixture concentration near the spark plug. However, fuel injected late in the compression stroke has a short atomization time, leading to incomplete combustion. Therefore, the smaller the injection quantity, the better, while ensuring successful ignition. Simultaneously, the injector must meet the fuel injection requirements for the engine's maximum power output, thus requiring a certain injector flow rate. Under current technological conditions, it is difficult to meet the demands of stratified lean combustion, high power output, and the minimal fuel injection at top dead center of the compression stroke using a single injector, while using two or more injectors increases costs and complicates layout. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that in the prior art, it is difficult to meet the requirements of high power and large fuel injection volume in stratified lean combustion and extremely small fuel injection volume at the top dead center of compression using a single injector, while using two or more injectors will lead to increased costs and difficulties in arrangement.

[0005] To address the aforementioned technical problems, this invention discloses a fuel injector, comprising a housing and a valve seat; wherein, a fuel passage is provided inside the housing, one end of the housing has a fuel inlet communicating with the fuel passage, and the other end of the housing is connected to and fixed relative to one end of the valve seat; the valve seat has a cavity inside, one end of the cavity is connected to and communicates with the end of the fuel passage away from the fuel inlet, and the other end of the valve seat has a fuel nozzle communicating with the cavity; the fuel injector further includes: an electromagnet, a moving component, and a limiting component; wherein,

[0006] The electromagnet is located inside the housing and outside the fuel passage, while the limiting component and the moving component are located inside the fuel passage.

[0007] The movable assembly includes a valve stem, an actuated component disposed at a first end of the valve stem, and a valve core disposed at a second end of the valve stem; the movable assembly is movable relative to the fuel passage between a first position, a second position, and a third position.

[0008] The limiting assembly includes a first limiting part, a second limiting part, a first elastic part, and a magnetic component. The first and second limiting parts are fixed to the fuel passage and are spaced apart from the fuel inlet towards the fuel outlet nozzle. The magnetic component is disposed between the first and second limiting parts and is slidably connected to the fuel passage. The first elastic part is disposed on the side of the attracted component near the fuel inlet and penetrates the magnetic component, with both ends of the first elastic part abutting against the attracted component and the inner wall of the fuel passage, respectively.

[0009] The electromagnet is positioned on the side of the first limiting portion away from the second limiting portion; the attracted component is a component that can be attracted by a magnetic component and by an electromagnet that has been magnetized; and...

[0010] When the moving component is in the first position, the electromagnet is de-energized, the attracted component separates from the magnetic component under the elastic force of the first elastic part, and the valve core abuts against the valve seat.

[0011] When the moving component is in the second position, the electromagnet is energized with a reverse current. The electromagnet and the magnetic component have the same magnetism. The magnetic component abuts against the second limiting part, and the attracted component abuts against the magnetic component. There is a first gap between the valve core and the valve seat.

[0012] When the moving component is in the third position, the electromagnet is energized with a positive current. The electromagnet and the magnetic component have different magnetic properties. The magnetic component abuts against the first limiting part, and the attracted component abuts against the magnetic component. There is a second gap between the valve core and the valve seat. The second gap is larger than the first gap.

[0013] Using the above technical solution, the injector has a compact structure and minimal change in external dimensions. By controlling the energizing direction of the electromagnet to generate magnetism that is different from or the same as that of the magnetic component, and combining this with the limiting component to adjust the lift of the moving component, the moving component is positioned in different locations, thereby changing the gap between the valve core and the valve seat. This achieves the function of changing the injection quantity by altering the internal flow cross-section of the injector, thus producing two different injection quantities. In this way, a single injector can meet the needs of stratified lean-burn high-power high-volume injection and minimal injection quantity at compression top dead center, reducing costs compared to the usual use of two injectors to achieve the same function.

[0014] When the electromagnet is de-energized, the attracted component separates from the magnetic component under the pressure of the first elastic part, allowing the valve core to abut against the valve seat. There is no gap between the valve core and the valve seat, and the injector does not inject fuel. When the electromagnet is energized with a reverse current, the magnetic polarity of the electromagnet is the same as that of the magnetic component. The magnetic component abuts against the second limiting part under the pressure of electromagnetic repulsion, while the attracted component overcomes the pressure of the first elastic part under the electromagnetic attraction, abutting against the magnetic component. This creates a smaller first gap between the valve core and the valve seat, resulting in a smaller lift of the moving component and a smaller injector flow rate, thus meeting the minimum fuel injection volume required at the top dead center of compression. When the electromagnet is energized with a forward current, the magnetic polarity of the electromagnet is opposite to that of the magnetic component. The magnetic component abuts against the first limiting part under the electromagnetic attraction, while the attracted component also overcomes the pressure of the first elastic part under the electromagnetic attraction, abutting against the magnetic component. This creates a larger second gap between the valve core and the valve seat, resulting in a larger lift of the moving component and a larger injector flow rate, thus meeting the maximum fuel injection volume required for the engine's maximum power. When the injector is turned on normally, its injection quantity is proportional to the injection pulse width. However, due to the different flow coefficients generated by the direction of electromagnet energization, the injection quantity is greater under the same injection pulse width under forward current than under reverse current.

[0015] According to another specific embodiment of the present invention, the fuel injector disclosed in the embodiment of the present invention further includes a second elastic part in the limiting component. The second elastic part is disposed on the side of the magnetic component near the fuel inlet and is located on the outer periphery of the first elastic part, and penetrates through the first limiting part. The two ends of the second elastic part abut against the magnetic component and the inner wall of the fuel passage, respectively. When the moving component is in the first position, the magnetic component abuts against the second limiting part under the elastic force of the second elastic part.

[0016] By adopting the above technical solution, by setting a second elastic part, when the electromagnet is de-energized, the magnetic component abuts against the second limiting part under the elastic force of the second elastic part; when the electromagnet is supplied with reverse current, the magnetic component firmly abuts against the second limiting part under the electromagnetic repulsion force and the elastic force of the second elastic part; the second elastic part is set on the side of the magnetic component near the oil inlet and passes through the first limiting part, when the electromagnet is supplied with forward current, the magnetic component smoothly abuts against the first limiting part under the electromagnetic attraction force and the elastic reverse force of the second elastic part.

[0017] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has a magnetic component that is a movable retaining ring made of permanent magnet material.

[0018] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has a first limiting part as a first limiting ring and a second limiting part as a second limiting ring; and the inner diameters of the first limiting ring and the second limiting ring are both larger than the inner diameter of the movable retaining ring.

[0019] Using the above technical solution, both the first and second limiting parts are configured as limiting rings. The inner diameters of both the first and second limiting rings are larger than the inner diameter of the movable retaining ring, ensuring that the movable retaining ring can only slide between the first and second limiting rings. Furthermore, when the movable retaining ring abuts against the first or second limiting ring, it ensures that the force around the movable retaining ring is uniform, thereby reducing the problem of shortened service life due to uneven force distribution.

[0020] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has an armature as the attracted component, the cross-section of the attracted component is circular, and the diameter of the attracted component is smaller than the inner diameter of the second limiting ring, so that the attracted component can pass through the second limiting ring; the diameter of the attracted component is larger than the inner diameter of the movable retaining ring.

[0021] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has a first elastic part as a first spring and a second elastic part as a second spring.

[0022] Using the above technical solution, both the first elastic part and the second elastic part are springs. The spring has a simple structure and can generate sufficient elastic force to ensure that when the electromagnet is de-energized, the attracted part can separate from the magnetic part under the pressure of the first spring, and the magnetic part can abut against the second limiting part under the pressure of the second spring.

[0023] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention includes an electromagnet comprising a connector and an electromagnetic coil; wherein the connector is electrically connected to the electromagnetic coil, and the electromagnetic coil is disposed on the outer periphery of the fuel passage.

[0024] With the above technical solution, the electromagnetic coil is set on the outer periphery of the fuel passage. When the electromagnetic coil is energized, the generated magnetic force is evenly distributed, and the moving component can move more smoothly relative to the fuel passage.

[0025] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has a spherical valve core and a spherical cavity in the valve seat that is adapted to the valve core.

[0026] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has an O-ring provided on the outer periphery of one end of the housing.

[0027] Using the above technical solution, an oil inlet is provided at one end of the housing. An O-ring is provided at the oil inlet to ensure the sealing of the injector, prevent fuel leakage, and ensure safety.

[0028] According to another specific embodiment of the present invention, the injector disclosed in the embodiment of the present invention has a sealing ring provided on the outer periphery of the housing near the valve seat.

[0029] Using the above technical solution, a sealing ring is provided on the outer periphery of the end of the housing near the valve seat for sealing the gas inside the engine cylinder with the outside.

[0030] The beneficial effects of this invention are:

[0031] This invention provides a fuel injector that adjusts the lift of a moving component by controlling the energizing direction of an electromagnet and combining it with a limiting component. This allows the moving component to be in different positions, thereby changing the gap between the valve core and the valve seat. In other words, it achieves the function of changing the fuel injection quantity by altering the internal flow cross-section of the injector. The electromagnet generates magnetism that is opposite to or the same as that of the magnetic component when current is applied in both directions, adjusting the lift of the magnetic component and the attracted component, thus producing two different fuel injection quantities. This allows a single injector to meet the needs of stratified lean-burn high-power high-volume fuel injection and minimal fuel injection at compression top dead center, reducing costs compared to the common practice of using two injectors to achieve the same function.

[0032] When the electromagnet is de-energized, the attracted component separates from the magnetic component under the pressure of the first elastic part, ensuring that the valve core and valve seat are in contact without gap, and the injector does not inject fuel. When the electromagnet is energized with a reverse current, the magnetic polarity of the electromagnet is the same as that of the magnetic component. The magnetic component abuts against the second limiting part under the pressure of electromagnetic repulsion, while the attracted component overcomes the pressure of the first elastic part under the electromagnetic attraction, abutting against the magnetic component. This results in a smaller first gap between the valve core and valve seat, meaning the moving component has a smaller lift and the injector flow rate, thus meeting the minimum fuel injection volume required at the top dead center of the engine compression stroke. When the electromagnet is energized with a forward current, the magnetic polarity of the electromagnet is opposite to that of the magnetic component. The magnetic component abuts against the first limiting part under the electromagnetic attraction, while the attracted component also overcomes the pressure of the first elastic part under the electromagnetic attraction, abutting against the magnetic component. This results in a larger second gap between the valve core and valve seat, meaning the moving component has a larger lift and the injector flow rate, thus meeting the maximum fuel injection volume required for the engine's maximum power. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the internal structure of the moving component of the injector in the first position according to an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the internal structure of the moving component of the injector in the second position according to an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the internal structure of the moving component of the injector in the third position according to an embodiment of the present invention.

[0036] Explanation of reference numerals in the attached figures:

[0037] 100: Housing; 110: Fuel passage; 120: Fuel inlet;

[0038] 200: Valve seat; 210: Cavity; 220: Oil nozzle;

[0039] 300: Electromagnet; 310: Connector; 320: Electromagnetic coil;

[0040] 400: Moving component; 410: Valve stem; 420: Actuated component; 430: Valve core;

[0041] 500: Limiting component; 510: First limiting part; 520: Second limiting part; 530: First elastic part; 540: Magnetic component; 550: Second elastic part;

[0042] 600: O-ring seal;

[0043] 700: Sealing ring. Detailed Implementation

[0044] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a deep understanding of the invention, many specific details will be included in the following description. The invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0045] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0046] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of the invention is usually placed in during use. They are only for the convenience of describing the present invention and 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 limiting the present invention.

[0047] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0048] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" 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 embodiment based on the specific circumstances.

[0049] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0050] This invention discloses an injector, such as... Figure 1 As shown, the device includes a housing 100 and a valve seat 200. The housing 100 has a fuel passage 110 inside, and one end of the housing 100 has an inlet 120 communicating with the fuel passage 110. The other end of the housing 100 is connected to and fixed relative to one end of the valve seat 200. The valve seat 200 has a cavity 210 inside, and one end of the cavity 210 is connected to and communicates with the end of the fuel passage 110 away from the inlet 120. The other end of the valve seat 200 has an outlet nozzle 220 communicating with the cavity 210.

[0051] In this embodiment, the fixed connection between the other end of the housing 100 and one end of the valve seat 200 includes, but is not limited to, welding, threaded connection, and integral molding. This embodiment does not impose specific limitations on these methods, and those skilled in the art can choose according to actual needs. The fuel passage 110 can be a cylindrical passage, a square-column passage, or a passage of other shapes. This embodiment does not impose specific limitations on these methods. Fuel enters from the fuel inlet 120 of the fuel injector, flows through the fuel passage 110, and is sprayed out from the fuel nozzle 220.

[0052] like Figure 1 As shown, the fuel injector also includes: an electromagnet 300, a moving component 400, and a limiting component 500; wherein, the electromagnet 300 is disposed inside the housing 100 and outside the fuel passage 110, and the limiting component 500 and the moving component 400 are disposed inside the fuel passage 110.

[0053] like Figure 1As shown, the movable assembly 400 includes a valve stem 410, a suction member 420 disposed at a first end of the valve stem 410, and a valve core 430 disposed at a second end of the valve stem 410, wherein the shape of the valve core 430 is adapted to the inner cavity shape of the valve seat 200. The movable assembly 400 is movable relative to the fuel passage 110 between a first position, a second position, and a third position. In this embodiment, the first end of the valve stem 410 is closer to the fuel inlet 120 than the second end.

[0054] like Figure 1 As shown, the limiting component 500 includes a first limiting portion 510, a second limiting portion 520, a first elastic portion 530, and a magnetic component 540. The first limiting portion 510 and the second limiting portion 520 are fixed to the fuel passage 110 and are spaced apart from the fuel inlet 120 towards the fuel outlet nozzle 220. In this embodiment, the first limiting portion 510 and the second limiting portion 520 are fixed to the fuel passage 110 by means including, but not limited to, welding and integral molding. The magnetic component 540 is disposed between the first limiting portion 510 and the second limiting portion 520 and is slidably connected to the fuel passage 110. The first limiting portion 510 and the second limiting portion 520 can limit the magnetic component 540 to slide only between the first limiting portion 510 and the second limiting portion 520.

[0055] like Figure 1 As shown, the first elastic portion 530 is disposed on the side of the attracted component 420 near the oil inlet 120 and penetrates the magnetic component 540. Both ends of the first elastic portion 530 abut against the inner walls of the attracted component 420 and the fuel passage 110, respectively. In this embodiment, the first elastic portion 530 includes, but is not limited to, a spring or a spring sheet. The electromagnet 300 is disposed on the side of the first limiting portion 510 away from the second limiting portion 520. The attracted component 420 is a non-magnetic component that can be attracted by the magnetic component 540 and the electromagnet 300. In this embodiment, the attracted component 420 can be a metal component. For example, it can be an iron component, a copper component, an alloy component, or an armature; this embodiment does not impose specific limitations on this.

[0056] And, as Figure 1 As shown, when the moving component 400 is in the first position, the electromagnet 300 is de-energized, the attracted component 420 is separated from the magnetic component 540 under the elastic force of the first elastic part 530, and the valve core 430 abuts against the valve seat 200.

[0057] like Figure 2As shown, when the moving component 400 is in the second position, the electromagnet 300 is supplied with a reverse current. The electromagnet 300 and the magnetic component 540 have the same magnetism. The magnetic component 540 abuts against the second limiting part 520, and the attracted component 420 abuts against the magnetic component 540. A first gap exists between the valve core 430 and the valve seat 200. It should be noted that in this embodiment, the first gap is small, and at this time, the injector has a small flow rate.

[0058] like Figure 3 As shown, when the moving component 400 is in the third position, the electromagnet 300 is supplied with a positive current. The electromagnet 300 and the magnetic component 540 have different magnetic properties. The magnetic component 540 abuts against the first limiting part 510, and the attracted component 420 abuts against the magnetic component 540. There is a second gap between the valve core 430 and the valve seat 200; the second gap is larger than the first gap. It should be noted that in this embodiment, the first gap is larger, and at this time, the injector has a large flow rate.

[0059] like Figure 1 and Figure 2 As shown, when the injector changes from a closed state to a low-flow state, the moving component 400 moves from a first position to a second position, and the electromagnet 300 changes from being de-energized to having a reverse current. The electromagnet 300 generates a magnetic force with the same polarity as the magnetic component 540. Under the electromagnetic repulsion of the electromagnet 300, the magnetic component 540 moves away from the electromagnet 300 until it abuts against the second limiting part 520. At the same time, the attracted component 420 moves from the position separated from the magnetic component 540, and under the electromagnetic attraction of the electromagnet 300, moves towards the electromagnet 300, i.e., as... Figure 1 As shown, it moves vertically upwards until it abuts against the magnetic component 540, simultaneously driving the valve core 430 to move as shown. Figure 1 It is moved upward in the vertical direction as shown to a position where it has a first gap with the valve seat 200.

[0060] like Figure 2 and Figure 3 As shown, when the injector changes from a low-flow state to a high-flow state, the moving component 400 moves from the second position to the third position, and the electromagnet 300 changes from being energized with reverse current to being energized with forward current. The electromagnet 300 generates a magnetic force with a polarity opposite to that of the magnetic component 540. Under the electromagnetic attraction of the electromagnet 300, the magnetic component 540 moves towards the electromagnet 300, i.e., as... Figure 3 As shown, it moves vertically upwards until it abuts against the first limiting part 510. Simultaneously, the attracted component 420 continues to move closer to the electromagnet 300 under the electromagnetic attraction of the electromagnet 300. Figure 3 As shown, it moves vertically upwards until it abuts against the magnetic component 540, simultaneously driving the valve core 430 to move as shown. Figure 3The magnetic component 540 moves upward in the vertical direction to a position where it has a second gap with the valve seat 200. In this embodiment, the size of the second gap can be determined based on the moving distance of the magnetic component 540 from the position abutting against the second limiting part 520 to the position abutting against the first limiting part 510 and the size of the first gap.

[0061] By employing the above technical solution, the lift of the moving component 400 is adjusted by controlling the energizing direction of the electromagnet 300 and combining it with the limiting component 500, so that the moving component 400 is in different positions, thereby changing the gap between the valve core 430 and the valve seat 200. That is, by changing the internal flow cross section of the injector, the fuel injection quantity is adjusted. The magnetic polarity generated by the electromagnet 300 passing current in both positive and negative directions is opposite to or the same as the magnetic polarity of the magnetic component 540, adjusting the lift of the magnetic component 540 and the attracted component 420, thereby producing two different fuel injection quantities.

[0062] When the electromagnet 300 is de-energized, the attracted component 420 separates from the magnetic component 540 under the pressure of the first elastic part 530, so that the valve core 430 abuts against the valve seat 200 without gap, and the injector does not spray oil.

[0063] When the electromagnet 300 is supplied with a reverse current, the magnetic polarity generated by the electromagnet 300 is the same as that of the magnetic component 540. Under the pressure of the electromagnetic repulsion force, the magnetic component 540 abuts against the second limiting part 520. At the same time, the attracted part 420 overcomes the pressure of the first elastic part 530 and abuts against the magnetic component 540 under the electromagnetic attraction force, so that there is a small first gap between the valve core 430 and the valve seat 200. That is, at this time, the lifting of the moving component 400 is small and the fuel injector flow is small, so as to meet the requirement of the minimum fuel injection amount at the top dead center of the engine compression.

[0064] When a positive current is applied to the electromagnet 300, the magnetic polarity generated by the electromagnet 300 is different from that of the magnetic component 540. The magnetic component 540 abuts against the first limiting part 510 under the electromagnetic attraction. At the same time, the attracted part 420 also overcomes the pressure of the first elastic part 530 and abuts against the magnetic component 540 under the electromagnetic attraction, so that there is a larger second gap between the valve core 430 and the valve seat 200. That is, at this time, the moving component 400 has a large lift and the injector flow is large, thereby meeting the large fuel injection volume requirement of the engine's maximum power.

[0065] In one specific implementation, such as Figure 1As shown, the limiting component 500 also includes a second elastic part 550. The second elastic part 550 is disposed on the side of the magnetic component 540 near the oil inlet 120 and is located on the outer periphery of the first elastic part 530, and passes through the first limiting part 510. The two ends of the second elastic part 550 abut against the inner wall of the magnetic component 540 and the fuel passage 110, respectively. When the moving component 400 is in the first position, under the elastic force of the second elastic part 550, the magnetic component 540 abuts against the second limiting part 520.

[0066] like Figure 1 and Figure 2 As shown, when the injector changes from a closed state to a low-flow state, the electromagnet 300 changes from being de-energized to having a reverse current, and the magnetic component 540 remains in contact with the second limiting part 520. In this embodiment, the size of the first gap can be determined based on the movement distance between the attracted component 420 and the position where it moves from a position separated from the magnetic component 540 to a position where it abuts the magnetic component 540.

[0067] By employing the above technical solution, and by providing the second elastic part 550, when the electromagnet 300 is de-energized, the magnetic component 540 abuts against the second limiting part 520 under the elastic force of the second elastic part 550; when the electromagnet 300 is supplied with a reverse current, the magnetic component 540 can firmly abut against the second limiting part 520 under the electromagnetic repulsion force and the elastic force of the second elastic part 550. The second elastic part 550 is located on the side of the magnetic component 540 near the oil inlet 120 and extends through the first limiting part 510. When the electromagnet 300 is supplied with a forward current, the magnetic component 540 can smoothly abut against the first limiting part 510 under the electromagnetic attraction force and the elastic reverse force of the second elastic part 550.

[0068] In one embodiment, the magnetic component 540 is a movable retaining ring made of permanent magnet material.

[0069] In one specific embodiment, the first limiting part 510 is a first limiting ring, and the second limiting part 520 is a second limiting ring; and the inner diameters of both the first and second limiting rings are larger than the inner diameter of the movable retaining ring. This ensures that the movable retaining ring can only slide between the first and second limiting rings. Furthermore, when the movable retaining ring abuts against the first or second limiting ring, it ensures that the force around the movable retaining ring is uniform, thereby reducing the problem of shortened service life of the movable retaining ring due to uneven force distribution.

[0070] In one specific embodiment, the attracted component 420 is an armature, the cross-section of the attracted component 420 is circular, and the diameter of the attracted component 420 is smaller than the inner diameter of the second limiting ring so that the attracted component 420 can pass through the second limiting ring. The diameter of the attracted component 420 is larger than the inner diameter of the movable retaining ring so as to limit the movement distance of the attracted component 420 relative to the fuel passage 110.

[0071] In one specific implementation, such as Figure 1 As shown, the first elastic part 530 is a first spring, and the second elastic part 550 is a second spring.

[0072] Using the above technical solution, both the first elastic part 530 and the second elastic part 550 are springs. The spring structure is simple and can generate sufficient elastic force to ensure that when the electromagnet 300 is de-energized, the attracted part 420 can separate from the magnetic part 540 under the pressure of the first spring, and the magnetic part 540 can abut against the second limiting part 520 under the pressure of the second spring.

[0073] In one specific implementation, such as Figure 1 As shown, the electromagnet 300 includes a connector 310 and an electromagnetic coil 320; wherein the connector 310 is electrically connected to the electromagnetic coil 320, and the electromagnetic coil 320 is disposed on the outer periphery of the fuel passage 110.

[0074] Using the above technical solution, the electromagnetic coil 320 is disposed on the outer periphery of the fuel passage 110. When the electromagnetic coil 320 is energized, the generated magnetic force is evenly distributed, and the moving component 400 can move more smoothly relative to the fuel passage 110.

[0075] In one specific implementation, such as Figure 1 As shown, the valve core 430 is spherical, and the cavity 210 of the valve seat 200 is a spherical cavity adapted to the valve core 430.

[0076] In one specific embodiment, an O-ring 600 is provided on the outer periphery of one end of the housing 100.

[0077] Using the above technical solution, an oil inlet 120 is provided at one end of the housing 100. An O-ring 600 is provided near the oil inlet 120 to ensure the sealing of the injector, prevent fuel leakage, and ensure safety.

[0078] In one specific embodiment, a sealing ring 700 is provided on the outer periphery of the end of the housing 100 near the valve seat 200.

[0079] Using the above technical solution, a sealing ring 700 is provided on the outer periphery of the end of the housing 100 near the valve seat 200 for sealing the gas inside the engine cylinder with the outside.

[0080] The beneficial effects of this invention are:

[0081] This invention provides a fuel injector that adjusts the lift of a moving component by controlling the energizing direction of an electromagnet and combining it with a limiting component. This allows the moving component to be in different positions, thereby changing the gap between the valve core and the valve seat. In other words, by changing the internal flow cross-section of the injector, the function of changing the fuel injection quantity is achieved. The electromagnet generates magnetism that is opposite or the same as that of the magnetic component when current is applied in both directions, thus adjusting the lift of the magnetic component and the attracted component, thereby producing two different fuel injection quantities. In this way, a single injector can meet the needs of stratified lean-burn high-power high-volume fuel injection and minimal fuel injection at compression top dead center, reducing costs compared to the usual use of two injectors to achieve the same function.

[0082] When the electromagnet is de-energized, the attracted component separates from the magnetic component under the pressure of the first elastic part, causing the valve core to abut against the valve seat, and the injector stops injecting fuel. When the electromagnet is energized with a reverse current, the magnetic polarity of the electromagnet is the same as that of the magnetic component. The magnetic component abuts against the second limiting part under the pressure of electromagnetic repulsion, while the attracted component overcomes the pressure of the first elastic part under the electromagnetic attraction, abutting against the magnetic component. This results in a smaller first gap between the valve core and the valve seat, meaning the moving component has a smaller lift and the injector flow rate, thus meeting the minimum fuel injection volume required at the top dead center of the engine compression stroke. When the electromagnet is energized with a forward current, the magnetic polarity of the electromagnet is opposite to that of the magnetic component. The magnetic component abuts against the first limiting part under the electromagnetic attraction, while the attracted component also overcomes the pressure of the first elastic part under the electromagnetic attraction, abutting against the magnetic component. This results in a larger second gap between the valve core and the valve seat, meaning the moving component has a larger lift and the injector flow rate, thus meeting the maximum fuel injection volume required for the engine's maximum power.

[0083] While the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the invention to these descriptions. Various changes in form and detail can be made by those skilled in the art, including several simple deductions or substitutions, without departing from the spirit and scope of the invention.

Claims

1. An injector, comprising a housing and a valve seat; wherein, The housing has a fuel passage inside, one end of the housing has an inlet communicating with the fuel passage, and the other end of the housing is connected to and fixed to one end of the valve seat. The valve seat has a cavity inside, one end of the cavity is connected to and communicates with the end of the fuel passage away from the inlet, and the other end of the valve seat has an outlet nozzle communicating with the cavity. The injector further includes: an electromagnet, a moving component, and a limiting component. The electromagnet is disposed inside the housing and outside the fuel passage, while the limiting component and the moving component are disposed inside the fuel passage; The movable assembly includes a valve stem, a suction-activated component disposed at a first end of the valve stem, and a valve core disposed at a second end of the valve stem; the movable assembly is movable relative to the fuel passage between a first position, a second position, and a third position; The limiting component includes a first limiting part, a second limiting part, a first elastic part, and a magnetic component; the first limiting part and the second limiting part are fixed on the fuel passage and are spaced apart from the fuel inlet towards the fuel outlet nozzle; the magnetic component is disposed between the first limiting part and the second limiting part and is slidably connected to the fuel passage; the first elastic part is disposed on the side of the attracted component near the fuel inlet and penetrates the magnetic component, and both ends of the first elastic part abut against the attracted component and the inner wall of the fuel passage, respectively; The electromagnet is located on the side of the first limiting portion away from the second limiting portion; the attracted component is a component that can be attracted by the magnetic component and the electromagnet that is magnetized; and... When the moving component is in the first position, the electromagnet is de-energized, the attracted component separates from the magnetic component under the elastic force of the first elastic part, and the valve core abuts against the valve seat; When the moving component is in the second position, the electromagnet is energized with a reverse current. The electromagnet and the magnetic component have the same magnetism. The magnetic component abuts against the second limiting part. The attracted component abuts against the magnetic component. There is a first gap between the valve core and the valve seat. When the moving component is in the third position, the electromagnet is energized with a positive current. The electromagnet and the magnetic component have different magnetic properties. The magnetic component abuts against the first limiting part. The attracted component abuts against the magnetic component. There is a second gap between the valve core and the valve seat. The second gap is larger than the first gap.

2. The injector as described in claim 1, characterized in that, The limiting component further includes a second elastic part, which is disposed on the side of the magnetic component near the oil inlet and located on the outer periphery of the first elastic part, and penetrates the first limiting part. The two ends of the second elastic part abut against the inner wall of the magnetic component and the fuel passage, respectively. When the moving component is in the first position, the magnetic component abuts against the second limiting part under the elastic force of the second elastic part.

3. The injector as described in claim 2, characterized in that, The magnetic component is a movable retaining ring made of permanent magnet material.

4. The injector as described in claim 3, characterized in that, The first limiting part is a first limiting ring, and the second limiting part is a second limiting ring; and the inner diameters of the first limiting ring and the second limiting ring are both larger than the inner diameter of the movable retaining ring.

5. The injector as described in claim 4, characterized in that, The attracted component uses an armature, the cross-section of the attracted component is circular, and the diameter of the attracted component is smaller than the inner diameter of the second limiting ring, so that the attracted component can pass through the second limiting ring; the diameter of the attracted component is larger than the inner diameter of the movable retaining ring.

6. The injector as described in claim 5, characterized in that, The first elastic part is a first spring, and the second elastic part is a second spring.

7. The injector as claimed in claim 6, characterized in that, The electromagnet includes a connector and an electromagnetic coil; wherein the connector is electrically connected to the electromagnetic coil, and the electromagnetic coil is disposed on the outer periphery of the fuel passage.

8. The injector as claimed in claim 7, characterized in that, The valve core is spherical, and the cavity of the valve seat is a spherical cavity adapted to the valve core.

9. The injector according to any one of claims 1-8, characterized in that, An O-ring is provided on the outer periphery of one end of the housing.

10. The injector according to any one of claims 1-8, characterized in that, A sealing ring is provided on the outer periphery of the end of the housing near the valve seat.

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