Pressure-static collaborative atomization high-frequency response electronic control fuel injector
By combining pressure-electrostatic synergistic atomization, the high-frequency response electronically controlled fuel injector solves the problem of fuel atomization under high injection pressure, achieving efficient fuel atomization and safety. It is suitable for high-pressure environments and low-flow conditions in engine combustion chambers.
Patent Information
- Application Number
- CN202520669597.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-10
- Publication Date
- 2026-01-16
- Estimated Expiration
- 2035-04-10
AI Technical Summary
Existing fuel injectors cannot effectively atomize fuel under high injection pressure, and electrostatic atomization technology has poor charging effect under high flow conditions, which cannot meet the fuel atomization requirements of the engine system.
The high-frequency response electronically controlled fuel injector employs pressure-electrostatic synergistic atomization, combining mechanical pressure and electrostatic force. Through a high-voltage charging module and a ratchet needle electrode design, it achieves efficient fuel atomization and prevents charge leakage through an insulating structure, thereby improving fuel charging efficiency and the frequency response characteristics of the injector.
It achieves high-quality fuel atomization under high pressure, improves combustion efficiency and fuel economy, ensures the safety and metering accuracy of the injector, and is suitable for high-pressure environments and low-flow conditions in engine combustion chambers.
Smart Images
Figure CN223806221U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to fuel injector technical field, concretely relates to a pressure-electrostatic collaborative atomization high frequency response electric control fuel injector. BACKGROUND
[0002] Fuel injector is an important component in engine system, and its atomization quality of liquid fuel directly affects fuel combustion efficiency, engine performance and combustion pollutant generation characteristics. The existing atomization technology includes pressure atomization, electrostatic atomization and ultrasonic atomization etc., and engine fuel injector is mainly based on pressure atomization principle. Actually, electrostatic atomization technology has the advantages of smaller atomized droplet size, better droplet dispersibility and controllability, and uniform droplet size distribution etc. A small part of previous researches on the application of electrostatic atomization technology in engine fuel injector, but is limited by two problems: first, most of the researches do not involve fuel electrostatic atomization under high injection pressure, because the actual engine combustion chamber is a high pressure environment, if the fuel injection pressure is low, the fuel cannot be effectively injected into the combustion chamber, so the research on fuel electrostatic atomization under medium and low pressure deviates from the actual engine working condition; second, some researches show that in order to realize fuel electrostatic atomization under high injection pressure, the volume of the charging cavity must be very small, so as to ensure that the fuel has good charge-to-mass ratio, that is, the existing technology cannot guarantee the charging effect under large flow fuel condition, and the fuel supply is limited, which leads to the fact that the electrostatic atomization technology under high injection pressure cannot support the main fuel atomization of engine system. In addition, the existing researches do not design the structure of electrostatic atomization fuel injector under high injection pressure on the basis of electric control fuel injector. SUMMARY
[0003] In view of the technical problems existing in the prior art, the utility model aims at providing a pressure-electrostatic collaborative atomization high frequency response electric control fuel injector, which has good atomization performance and safety, and is suitable for the high pressure environment of actual engine combustion chamber and small flow fuel working condition.
[0004] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme:
[0005] A pressure-electrostatic collaborative atomization high frequency response electric control fuel injector, comprising an oil inlet mechanism, an electromagnetic mechanism, a transmission mechanism, a shell, a high-voltage charging module and a receiving valve, the shell has a mounting chamber, an oil inlet, an electricity inlet and an oil outlet, the oil inlet mechanism is arranged at the oil inlet, the electromagnetic mechanism is arranged in the mounting chamber, one end of the electromagnetic mechanism is connected with the oil inlet mechanism, and the electromagnetic mechanism is used to drive the receiving valve to open; the transmission mechanism is connected with the receiving valve and used to drive the receiving valve to close, the receiving valve is arranged at the oil outlet, and the ratchet needle electrode of the high-voltage charging module is arranged towards the outlet of the receiving valve; the second wire harness plug of the high-voltage charging module and the first wire harness plug of the electromagnetic mechanism are both arranged at the electricity inlet.
[0006] As a kind of preferred, oil inlet mechanism includes oil inlet pipe, fuel filter screen and first sealing ring, part of oil inlet pipe is inserted into oil inlet, electromagnetic mechanism is docked with the part of oil inlet pipe inserted into oil inlet, first sealing ring is arranged between the part of oil inlet pipe outside oil inlet and oil inlet, fuel filter screen is arranged in oil inlet pipe.
[0007] As a kind of preferred, electromagnetic mechanism includes iron core, wire holder, electromagnetic coil, first wire harness plug, sleeve, second sealing ring and magnetic shield sleeve;Wire holder is arranged in installation chamber, electromagnetic coil is wound on wire holder, iron core penetrates electromagnetic coil, one end of iron core is docked with oil inlet mechanism, iron core is sleeved on the outside of transmission mechanism;First wire harness plug is arranged in power inlet, electromagnetic coil is connected with first wire harness plug through wire, electromagnetic coil is also used to be connected with ECU control unit in generator system;Magnetic shield sleeve is installed at the bottom of wire holder, second sealing ring is arranged between magnetic shield sleeve and wire holder, sleeve is fixed in installation chamber, sleeve is interference fit with wire holder and magnetic shield sleeve.
[0008] As a kind of preferred, transmission mechanism includes pressure regulating elastic pin and return spring, pressure regulating elastic pin is inserted into iron core and fixed, one end of return spring is fixed at the end of pressure regulating elastic pin, the other end of return spring is connected with receiving valve.
[0009] As a kind of preferred, high-voltage charging module includes high-voltage charging cavity, terminal, ratchet needle electrode, primary insulation protection sheet and second wire harness plug, insulation oil cavity is arranged in shell, insulation oil cavity is fixed below magnetic shield sleeve, high-voltage charging cavity is arranged below insulation oil cavity, primary insulation protection sheet is fixed in high-voltage charging cavity, terminal is arranged in the side wall of high-voltage charging cavity and below primary insulation protection sheet;Second wire harness plug is arranged in power inlet, one end of terminal is connected with second wire harness plug through wire, the other end of terminal is connected with ratchet needle electrode, ratchet needle electrode is arranged in high-voltage charging cavity.
[0010] As a kind of preferred, high-voltage charging cavity is variable-diameter structure.
[0011] As a kind of preferred, the receiving valve includes valve seat, receiving armature and needle valve body, valve seat is arranged at oil outlet, valve seat is wrapped in the outside of high-pressure charged cavity, the bottom of valve seat is provided with hollow spherical fuel spray head;Insulating oil cavity inner gap fits limit baffle, and there is gap between limit baffle and the bottom end of iron core;Receiving armature includes first cylinder and second cylinder, first cylinder is fixed at the bottom of reset spring, second cylinder is fixed at the bottom of first cylinder, the outer diameter of second cylinder is less than the outer diameter of first cylinder, the outer diameter of first cylinder is same with the outer diameter of limit baffle, the top of first cylinder is fixedly connected with limit baffle, the part of first cylinder with larger outer diameter than second cylinder is provided with oil passage, the bottom of second cylinder is provided with connecting hole, needle valve body is fixedly connected with connecting hole, needle valve body is matched with oil outlet to open and close hollow spherical fuel spray head;Wherein, the surface of hollow spherical fuel spray head has multiple conical spray holes.
[0012] As a kind of preferred, two-stage insulation protection sheet is fixed in insulating oil cavity, and the two-stage insulation protection sheet is located below receiving armature.
[0013] As a kind of preferred, the prong type needle electrode has multiple prong type branches, and the prong type branches have pointed ends pointing to the hollow spherical fuel spray head.
[0014] As a kind of preferred, the surface of needle valve body is provided with insulation coating.
[0015] Overall, the utility model has the following advantages:
[0016] (1) the utility model provides a kind of high-frequency response electric control oil atomizer of pressure-electrostatic collaborative atomization, so that electrostatic atomization technology can be applied in high-pressure environment in engine combustion chamber.For the atomization of small flow pilot fuel in engine dual-fuel combustion mode, the technical matching degree is higher, the atomization quality of electrostatic atomization technology is good, and the fuel can have good charging effect.
[0017] (2) The pressure-electrostatic synergistic atomization high-frequency response electric control fuel injector of the utility model in work, liquid fuel is broken into tiny droplets under the synergistic effect of mechanical pressure and electrostatic force. Specifically, pressure atomization is to spray high-pressure fuel into the combustion chamber through a nozzle with extremely small aperture, thereby realizing the atomization of liquid fuel. The high-pressure condition enables the fuel droplets to obtain greater initial kinetic energy, which is compatible with the high-pressure environment of the combustion chamber in the engine system and ensures that the droplets have a greater penetration distance in the combustion chamber. Electrostatic atomization carries the same charge on the fuel droplets. When the Rayleigh limit is reached, the internal electric field force of the fuel overcomes the liquid surface tension, causing the liquid fuel to break into a large number of tiny droplets with the same charge. The droplets disperse under the action of the Coulomb repulsive force. The principle is that the droplet charging limit is proportional to the droplet radius. The smaller the droplet, the smaller the amount of charge required for breaking, and under the same electrostatic condition, a better atomization effect can be achieved. Based on the traditional pressure atomization that causes the droplets to break once, electrostatic atomization can cause the droplets to break twice, obtaining a fuel droplet group with smaller particle size, better uniformity, and dispersion, significantly improving the fuel atomization quality, thereby promoting the gasification process of the liquid fuel, ensuring the combustion efficiency of the fuel, and improving the fuel economy.
[0018] (3) The pressure-electrostatic synergistic atomization high-frequency response electric control fuel injector of the utility model adopts a closed contact corona charging structure to charge the fuel through contact charging and corona charging. A high-voltage charging cavity made of high-strength insulating material and a first-level insulating protective sheet establish a nearly closed charging structure, a ratchet-shaped needle electrode is designed to generate as many discharge tips as possible to intensify corona discharge. In addition, the overall shape of the designed ratchet-shaped needle electrode is similar to that of the high-voltage charging cavity, and the ratchet-shaped branch tips are close to and point towards the fuel injection hole, further optimizing the electric field distribution in the charging cavity and improving the fuel charging efficiency.
[0019] (4) The pressure-electrostatic synergistic atomization high-frequency response electric control fuel injector of the utility model sets two levels of insulation protection in the insulating oil cavity to reduce charge diffusion through the first and second insulation protective sheets, and covers an insulating coating on the surface of the needle valve body to prevent the needle valve body from guiding the charge to the transmission mechanism and electromagnetic mechanism, preventing problems such as magnetization of the electromagnetic transmission mechanism and inaction caused by charge leakage, and enhancing safety.
[0020] (5) The pressure-electrostatic synergistic atomization high-frequency response electric control fuel injector of the utility model separates the iron core and the armature by setting a magnetic isolation sleeve at the bottom of the online frame and using a limiting stop ring made of high-strength non-magnetic material, which ensures that the fuel injector can effectively avoid the phenomenon of lagging seat of the receiving valve caused by hysteresis effect when the electric excitation signal rapidly decreases, thereby improving the frequency response characteristics and fuel injection accuracy of the electric control fuel injector. BRIEF DESCRIPTION OF DRAWINGS
[0021] Fig. 1 It is a sectional view of a pressure-electrostatic synergistic atomization high-frequency response electric control fuel injector;
[0022] Fig. 2 It is a local schematic view of the electric charging cavity of the fuel injector;
[0023] Wherein: 1, fuel filter screen; 2, oil inlet pipe; 3, first sealing ring; 4, shell; 5, iron core; 6, pressure regulating elastic pin; 7, wire holder; 8, electromagnetic coil; 9, return spring; 10, second sealing ring; 11, magnetic isolation sleeve; 12, sleeve; 13, insulating oil cavity; 14, limit check ring; 15, receiving armature; 16, needle valve body; 17, two-stage insulation protection sheet; 18, one-stage insulation protection sheet; 19, valve seat; 20, high-voltage electric charging cavity; 21, wiring terminal; 22, ratchet needle electrode; 23, first wire harness plug; 24, second wire harness plug. DETAILED DESCRIPTION
[0024] The utility model will be further explained in detail in combination with specific embodiments.
[0025] In combination Figs. 1-2 , the utility model provides a pressure-electrostatic synergistic atomization high-frequency response electric control fuel injector, including oil inlet mechanism, electromagnetic mechanism, transmission mechanism, shell, high-voltage electric charging module and receiving valve, the shell has installation chamber, oil inlet, electricity inlet and oil outlet, and oil inlet mechanism is arranged at oil inlet, and electromagnetic mechanism is arranged in installation chamber, and one end of electromagnetic mechanism is docked with oil inlet mechanism, and electromagnetic mechanism is used to drive receiving valve to open, transmission mechanism is connected with receiving valve and is used to drive receiving valve to close, and receiving valve is arranged at oil outlet, and the ratchet needle electrode of high-voltage electric charging module is arranged towards the outlet of receiving valve, and the second wire harness plug of high-voltage electric charging module and the first wire harness plug of electromagnetic mechanism are all arranged at electricity inlet.
[0026] Specifically, the shell 4 has a through hole along the central axis thereof, and the two ends of the through hole are an oil inlet and an oil outlet, respectively, and the installation chamber is connected downstream of the oil inlet, and the oil inlet mechanism, the electromagnetic mechanism, the high-voltage electric charging module and the receiving valve are sequentially arranged in the through hole from top to bottom; the side wall of the shell is provided with an electricity inlet.
[0027] The oil inlet mechanism includes an oil inlet pipe 2, a fuel filter screen 1 and a first sealing ring 3; the lower half of the oil inlet pipe 2 is fixed in the oil inlet, the upper surface of the first sealing ring 3 is in full contact with the part of the oil inlet pipe 2 located outside the shell, and the lower surface is pressed against the upper end surface of the shell 4 (the end surface at the oil inlet), and the fuel filter screen 1 is welded in the oil inlet pipe 2.
[0028] The electromagnetic mechanism comprises a core 5, a wire frame 7, an electromagnetic coil 8, a first wire harness plug 23, a sleeve 12, a second sealing ring 10 and a magnetic shield 11. The upper end of the core 5 is connected to the bottom of the oil inlet pipe 2, and the whole is installed in the installation chamber and penetrates the electromagnetic coil 8 wound on the wire frame 7. The electromagnetic coil 8 is connected with the first wire harness plug 23 and the ECU control unit in the engine system through wires in sequence. The magnetic shield 11 is installed at the bottom of the wire frame 7, and the second sealing ring 10 is arranged between the two to play a sealing role. The sleeve 12 is fixed in the shell 4 and is in interference fit with the lower half of the wire frame 7 and the magnetic shield 11 to play a positioning and secondary sealing role. The core is provided with an axial hole penetrating the length direction thereof.
[0029] The transmission mechanism comprises a pressure regulating elastic pin 6 and a return spring 9. The return spring 9 in the transmission mechanism is welded at the bottom of the pressure regulating elastic pin 6. The position of the pressure regulating elastic pin 6 can be adjusted to change the initial deformation length of the return spring 9, so as to change the pressure of the needle valve body 16 on the valve seat 19 (when the fuel injector stops spraying, the needle valve body tightly abuts against the nozzle part of the valve seat). The pressure regulating elastic pin 6 after the spring pressure is adjusted is welded or in interference fit in the axial hole of the core 5.
[0030] The installation area between the installation chamber and the oil outlet has an insulating oil cavity 13. The installation area of the insulating oil cavity 13 is provided with the insulating oil cavity 13. The limiting baffle 14 is a hollow cylinder made of high-strength non-magnetic material and is in clearance fit in the insulating oil cavity 13. The upper end surface of the limiting baffle 14 is kept a certain distance from the bottom end of the core 5.
[0031] The high-voltage charging module comprises a high-voltage charging cavity 20, a wiring terminal 21, a ratchet needle electrode 22, a first insulation protection sheet 18 and a second wire harness plug 24. The high-voltage charging cavity 20 is arranged below the insulating oil cavity 13. The first insulation protection sheet is fixed in the high-voltage charging cavity. The wiring terminal is arranged on the side wall of the high-voltage charging cavity and is located below the first insulation protection sheet. The second wire harness plug is arranged at the power inlet. One end of the wiring terminal is connected with the second wire harness plug through wires. The other end of the wiring terminal is connected with the ratchet needle electrode. The ratchet needle electrode is arranged in the high-voltage charging cavity.
[0032] The bearing valve comprises a valve seat 19, a bearing armature 15 and a needle valve body 16. The valve seat is arranged at the oil outlet. The valve seat 19 made of high-temperature-resistant metal material integrally wraps the high-voltage charging cavity 20. The bottom end of the valve seat 19 is an integrated hollow spherical fuel nozzle. A plurality of conical injection holes are opened on the surface of the nozzle. At the moment when the fuel injector stops spraying, the bottom tip of the needle valve body 16 tightly abuts against the injection hole to prevent fuel leakage.
[0033] The insulating oil cavity 13 is fixed at the lower part of the magnetic shield 11 and is connected with the high-voltage charging cavity at the bottom surface. The upper part of the bearing valve is arranged in the insulating oil cavity 13, and the lower part is arranged in the high-voltage charging cavity.
[0034] The shaft of the bearing armature 15 is welded at the bottom of the return spring 9; the bearing armature 15 is a spliced variable-diameter cylinder, specifically, the bearing armature includes a first cylinder and a second cylinder, the first cylinder is fixed at the bottom of the return spring, the second cylinder is fixed at the bottom of the first cylinder, the outer diameter of the second cylinder is smaller than that of the first cylinder, the diameter d1 of the first cylinder is the same as the outer diameter of the limiting check ring 14, and the upper end surface is tightly fixed with the bottom surface of the limiting check ring 14; the diameter d2 of the second cylinder is slightly smaller than d1, and a plurality of narrow oil holes are evenly arranged in the range of d1-d2 on the first cylinder to ensure that the fuel enters the insulating oil cavity 13; a connecting hole is arranged at the bottom of the second cylinder, and the needle valve body 16 is welded to the upper end of the connecting hole, and the surface of the needle valve body 16 is covered with an insulating coating to prevent the magnetization of the transmission mechanism and the inaccuracy of the fuel injection caused by the leakage of the high-voltage charged module.
[0035] The insulating oil cavity 13 and the high-voltage charged cavity are both variable-diameter structures made of high-temperature and high-pressure resistant insulating materials, that is, both have a large-diameter section, a variable-diameter section and a small-diameter section, the first-level and second-level insulation protection sheets 18 and 17 are respectively fixed in front of the variable-diameter sections inside the high-voltage charged cavity 20 and the insulating oil cavity 13; the first-level and second-level insulation protection sheets are both circular ring structures made of high-strength insulating materials, the outer diameters of the two are matched with the sizes of the installation positions, and the inner diameters of the two are the same and slightly larger than the diameter of the variable-diameter section of the needle valve body 16, thereby forming a narrow fuel passage, reducing the loss of electric charge and enhancing safety.
[0036] The wiring terminal is arranged below the first-level insulation protection sheet 18 and is fixed to the side wall of the high-voltage charged cavity 20, one end of the wiring terminal is connected to the second wire harness plug 24 through a wire, and the high-voltage generator controlled by the ECU control unit in the engine system provides high-voltage static electricity; the other end is connected to the ratchet needle electrode 22 arranged in the high-voltage charged cavity 20, and a plurality of ratchet needle electrodes 22 are evenly distributed on the same height cross section inside the high-voltage charged cavity 20. The ratchet needle electrode 22 has a plurality of ratchet branches, the tips of the ratchet branches are close to and point to the injection holes of the hollow spherical fuel spray head at the bottom of the valve seat 19, so as to ensure that the fuel near the hollow spherical fuel spray head has a high charge density, improve the oil mass ratio, and further reduce the loss of electric charge.
[0037] The working principle is as follows:
[0038] The electromagnetic coil 8 is connected to the first wire harness plug 23 and the ECU control unit in the engine system through wires in sequence, and the frequency and on-off of the electric excitation signal are controlled by the ECU control unit, thereby controlling the precise fuel injection of the high-voltage static fuel injector. When there is no electric excitation signal in the electromagnetic coil 8 (no fuel injection time), the tip of the bottom of the needle valve body 16 tightly abuts against the conical injection hole under the pressure of the return spring 9, preventing the high-voltage charged fuel in the high-voltage charged cavity 20 from being injected into the engine combustion chamber.
[0039] When the electromagnetic coil receives the electric excitation signal, the electromagnetic coil generates a magnetic field, the iron core 5 further enhances the magnetic field intensity, the receiving armature 15 is attracted upward by the electromagnetic force, the limiting stop ring 14 and the needle valve body 16 move upward with the receiving armature 15, until the top of the limiting stop ring 14 abuts against the bottom end of the iron core 5. At this time, the high-pressure charged fuel in the high-pressure charged cavity 20 is communicated with the engine combustion chamber through the injection hole of the valve seat 19, and the fuel is injected into the combustion chamber under the action of oil pressure. At the same time, the fuel is atomized into tiny droplets under the dual action of pressure and electrostatic force, and the liquid droplets with the same charge are further dispersed in the combustion chamber under the action of the Coulomb repulsive force.
[0040] When the electric excitation signal stops, since the limiting stop ring 14 and the magnetic shielding sleeve 11 are made of non-magnetic materials, the magnetic field of the electromagnetic coil 8 disappears rapidly, the receiving armature 15 and the limiting stop ring 14 are quickly separated from the iron core 5 under the action of the spring force of the return spring 9, and the state that the needle valve body 16 tightly abuts against the injection port of the valve seat 19 is restored, the magnetic hysteresis effect is effectively avoided, the action precision of the receiving valve is improved, and the normal work of the fuel injector is ensured.
[0041] The above embodiment is the preferred embodiment of the utility model, but the embodiment of the utility model is not limited by the above embodiment, any change, modification, replacement, combination, simplification made without departing from the spirit and principle of the utility model should be an equivalent replacement mode, and all are included in the protection scope of the utility model.
Claims
1. A pressure-electrostatic synergistic atomizing high frequency response electronically controlled fuel injector, characterized in that: The oil inlet mechanism, the electromagnetic mechanism, the transmission mechanism, the shell, the high-voltage charging module and the receiving valve are included.
2. A pressure-electrostatic synergic atomizing high frequency response electronically controlled fuel injector according to claim 1, characterized in that: The oil inlet mechanism includes an oil inlet pipe, a fuel filter screen and a first sealing ring, part of the oil inlet pipe is inserted into the oil inlet port, the electromagnetic mechanism is connected with the part of the oil inlet pipe inserted into the oil inlet port, the first sealing ring is arranged between the part of the oil inlet pipe outside the oil inlet port and the oil inlet port, and the fuel filter screen is arranged in the oil inlet pipe.
3. A pressure-electrostatic synergic atomizing high frequency response electronically controlled fuel injector according to claim 1, characterized in that: The electromagnetic mechanism includes a core, a wire holder, an electromagnetic coil, a first wire harness plug, a sleeve, a second sealing ring and a magnetic shield sleeve.
4. A pressure-electrostatic synergic atomizing high frequency response electronically controlled fuel injector according to claim 3, characterized in that: The transmission mechanism includes a pressure regulating elastic pin and a return spring, the pressure regulating elastic pin is inserted into the core and fixed, one end of the return spring is fixed to the end of the pressure regulating elastic pin, and the other end of the return spring is connected with the receiving valve.
5. A pressure-electrostatic synergic atomizing high frequency response electronically controlled fuel injector according to claim 3, characterized in that: The high-voltage charging module includes a high-voltage charging cavity, a wiring terminal, a ratchet needle electrode, a primary insulation protection sheet and a second wire harness plug, an insulation oil cavity is arranged in the shell, the insulation oil cavity is fixed below the magnetic shield sleeve, the high-voltage charging cavity is arranged below the insulation oil cavity, the primary insulation protection sheet is fixed in the high-voltage charging cavity, the wiring terminal is arranged on the side wall of the high-voltage charging cavity and below the primary insulation protection sheet, and the second wire harness plug is arranged in the power inlet port.
6. A pressure-electrostatic synergic atomizing high frequency response electronically controlled fuel injector according to claim 5, characterized in that: The high-voltage charging cavity has a variable diameter structure.
7. A pressure-electrostatic synergistic atomizing high frequency response electronically controlled fuel injector according to claim 5, characterized in that: The valve includes a valve seat, a valve arm and a needle valve body, the valve seat is arranged at the oil outlet, the valve seat is wrapped outside the high-pressure charged cavity, the bottom of the valve seat is provided with a hollow spherical fuel injection head; a limiting ring is arranged in the insulating oil cavity in a clearance fit, and a gap is formed between the limiting ring and the bottom end of the iron core; the valve arm includes a first cylinder and a second cylinder, the first cylinder is fixed at the bottom of the reset spring, the second cylinder is fixed at the bottom of the first cylinder, the outer diameter of the second cylinder is smaller than that of the first cylinder, the outer diameter of the first cylinder is the same as that of the limiting ring, the top of the first cylinder is fixedly connected with the limiting ring, the part of the first cylinder with a larger outer diameter than the second cylinder is provided with an oil passage, the bottom of the second cylinder is provided with a connecting hole, and the needle valve body is fixedly connected with the connecting hole, the needle valve body is matched with the oil outlet to open and close the hollow spherical fuel injection head; wherein the surface of the hollow spherical fuel injection head is provided with a plurality of conical injection holes.
8. A pressure-electrostatic synergic atomizing high frequency response electronically controlled fuel injector according to claim 7, characterized in that: A secondary insulation protection sheet is fixed in the insulating oil cavity and located below the valve arm.
9. A pressure-electrostatic synergistic atomizing high frequency response electronically controlled fuel injector according to claim 7, characterized in that: The prong type needle electrode has a plurality of prong type branches, and the prong type branches have pointed ends pointing to the hollow spherical fuel injection head.
10. A pressure-electrostatic synergistic atomizing high frequency response electronically controlled fuel injector according to claim 7, characterized in that: The surface of the needle valve body is provided with an insulating coating.