CN118959198A - Controllable sprayer based on double-valve control injection strategy - Google Patents

Abstract

The invention aims to provide an injector with controllable injection strategy based on double-valve control, and belongs to the field of engine fuel devices. The invention can be used as a dual fuel injector for injecting zero carbon fuel and diesel oil, and also can be used as a variable injection rule injector for injecting diesel oil only; the device comprises a first electromagnetic valve, a second electromagnetic valve, a first fuel inlet, a second fuel inlet, a first control oil cavity, a second control oil cavity, an inner needle valve body, an outer needle valve body, an inner spray hole and an outer spray hole; when the fuel injector is used as a dual fuel injector, zero carbon fuel enters from a first fuel inlet, and diesel oil enters through a second fuel inlet; when only diesel oil is injected, both the first fuel inlet and the second fuel inlet are communicated with diesel oil. The two electromagnetic valves are used for respectively controlling the opening and closing of the inner needle valve body and the outer needle valve body, so that the purposes of realizing the injection of the zero-carbon fuel and the diesel oil on one injector and the changeable diesel oil injection rule are achieved, and the carbon emission reduction and the performance improvement of the power-assisted engine can be effectively realized.

Description

Controllable sprayer based on double-valve control injection strategy

Technical Field

The invention relates to an engine, in particular to an engine fuel device.

Background

The mode of reducing carbon emission of the engine power system can be realized by widely using zero carbon fuel or improving the dynamic property, economy and emission of the existing power system such as a diesel engine and the like.

For zero-carbon fuels such as green methanol, green ammonia and the like, the aim of greatly reducing the carbon emission of the engine can be fulfilled; however, these fuels often suffer from low activity and slow flame propagation speed, so that a dual direct injection zero-carbon fuel and diesel fuel mode is generally adopted, the zero-carbon fuel is ignited by using diesel fuel, and the carbon emission of the engine is reduced by improving the substitution rate of the zero-carbon fuel.

At present, two ways of directly spraying zero-carbon fuel and diesel oil can be realized, one way is to install two injectors on a cylinder cover to respectively spray the two fuels, however, the way not only occupies the space of the cylinder cover and is difficult to process, but also because the diesel injector does not work for a long time, the nozzle cannot be fully cooled by the fuel oil and is easy to overheat and damage; the other is to spray two kinds of fuels through one injector, which can save space and cool the nozzle effectively, but the existing integrated injector is complex in oil path and difficult to process, and the electromagnetic valve increases more energy consumption of the whole injector or has single injection strategy and cannot be flexibly controlled.

The performance of diesel engines is often improved by requiring variable injection rates of injectors, which are typically achieved by varying the fuel pressure of existing injectors, which not only have a slow response speed but also tend to increase the size of the injectors to a greater extent, reducing the overall engine performance.

Disclosure of Invention

The invention aims to provide an ejector which can reduce carbon emission of an engine power system and is controllable based on a double-valve control injection strategy.

The purpose of the invention is realized in the following way:

The invention discloses an injector with controllable injection strategy based on double-valve control, which is characterized in that: the injector comprises an injector body, a first middle block, a second middle block, a third middle block, a metering orifice plate and an outer needle valve sleeve which are arranged from top to bottom, wherein the injector body, the first middle block, the second middle block, the third middle block, the metering orifice plate and the outer needle valve sleeve are fixed together through an external fastening sleeve, a first fuel inlet is arranged on injection gas, a second oil outlet device is arranged in the first middle block and the second middle block, a first oil outlet device is arranged in the second middle block and the third middle block, a second fuel inlet is arranged on the metering orifice plate, an outer needle valve body is arranged in the outer needle valve sleeve, and an inner needle valve body is arranged in the outer needle valve body.

The invention may further include:

1. the second oil outlet device comprises a second electromagnetic valve, a second armature, a second valve rod and a second ball valve, wherein a second armature reset spring is arranged in the second electromagnetic valve, the bottom end of the second armature reset spring is propped against the second armature, two ends of the second valve rod are respectively positioned in the second armature and a second middle block, the second armature is fixed with the second valve rod, the second ball valve is connected to the lower part of the second valve rod, and a second oil outlet orifice is arranged in the second middle block below the second ball valve.

2. The oil outlet device comprises an electromagnetic valve, an armature, a valve rod and a ball valve, wherein an armature reset spring is arranged in the electromagnetic valve, the bottom end of the armature reset spring is propped against the armature, two ends of the valve rod are respectively positioned in an armature and a third middle block, the armature is fixed with the valve rod, the lower part of the valve rod is connected with the ball valve, and an oil outlet orifice is arranged in a thirteenth middle block below the ball valve.

3. An inner needle valve reset spring and a plug are arranged in the metering orifice plate, the upper end and the lower end of the inner needle valve reset spring are respectively provided with a third intermediate block and a plug, the top of the inner needle valve body is positioned below the plug, the outer needle valve is sleeved outside the inner needle valve body, the two ends of the outer needle valve reset spring are respectively provided with the metering orifice plate and the outer needle valve body, the middle part of the inner needle valve body is provided with a middle fuel channel which is communicated with a second fuel inlet, a first control oil cavity is formed between the metering orifice plate and the outer needle valve body below the metering orifice plate, the position of the inner needle valve reset spring forms a second control oil cavity, a first oil inlet orifice and a second oil inlet orifice are respectively arranged in the metering orifice plate, the first oil inlet orifice is respectively communicated with the second fuel inlet and the first control oil cavity, and the second oil inlet orifice is respectively communicated with the second fuel inlet and the second control oil cavity; the first oil outlet orifice is communicated with the first control oil cavity, and the second oil outlet orifice is communicated with the second control oil cavity.

4. An outer needle valve sleeve and an outer needle valve body are arranged between the outer needle valve sleeve and the outer needle valve body, an inner needle valve pressure chamber is formed between the outer needle valve body and the inner needle valve body, the inner needle valve pressure chamber is communicated with an intermediate fuel channel, the outer needle valve pressure chamber is communicated with a first fuel inlet, an inner needle valve seat matched with the inner needle valve body is arranged at the bottom of the outer needle valve body, inner spray holes are arranged on the inner needle valve seat, and outer spray holes are arranged at the bottom of the outer needle valve sleeve.

5. The injection gas is internally provided with an accumulation cavity, a first fuel inlet is communicated with the accumulation cavity, and a sealing cap is arranged at the top of the accumulation cavity.

6. The total aperture of the inner spray hole is smaller than that of the outer spray hole, namely the inner spray hole is used for micro-injection of fuel, and the outer spray hole is used for mass injection.

7. The first fuel inlet is filled with zero carbon fuel so as to enter an accumulation cavity and an outer needle valve pressure chamber, the second fuel inlet is filled with diesel oil, one path of the fuel enters a first control oil cavity through a first oil inlet orifice, the other path of the fuel enters a second control oil cavity through a second oil inlet orifice, the other path of the fuel enters an inner needle valve pressure chamber through an intermediate fuel channel, an inner needle valve body is pressed on an inner needle valve seat by downward diesel oil hydraulic pressure in the second control oil cavity and elastic force of an inner needle valve return spring, and an outer needle valve body is pressed on an outer needle valve sleeve by downward diesel oil hydraulic pressure in the first control oil cavity and elastic force of the outer needle valve return spring;

Diesel oil is used as a pilot fuel to carry out micro injection through an inner jet orifice, and zero carbon fuel is used as a main fuel to carry out mass injection through an outer jet orifice; if the diesel oil is injected, the second electromagnetic valve is electrified, the second armature iron drives the second valve rod to move upwards, the second ball valve is opened, the diesel oil in the second control oil cavity flows out through the second oil outlet orifice to release pressure, and when the upward hydraulic pressure of the diesel oil in the inner needle valve pressure chamber is greater than the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the inner needle valve return spring, the inner needle valve is opened to inject the diesel oil; if the zero carbon fuel is to be injected, the first electromagnetic valve is electrified, the first armature iron drives the first valve rod to move upwards, the first ball valve is opened, diesel oil in the first control oil cavity flows out through the first oil outlet orifice to release pressure, and when the outer needle valve body is subjected to the fact that the upward hydraulic pressure of the low carbon fuel in the outer needle valve pressure chamber is greater than the downward hydraulic pressure of the diesel oil in the first control oil cavity and the elastic force of the outer needle valve body reset spring, the outer needle valve body is opened to inject the low carbon fuel.

8. The first fuel channel and the second fuel channel are communicated with diesel oil, and the diesel oil entering from the first fuel channel immediately enters the outer needle valve pressure chamber; the diesel oil entering from the second fuel channel enters the first control oil cavity through the first oil inlet orifice, enters the second control oil cavity through the second oil inlet orifice, enters the inner needle valve pressure chamber through the middle fuel channel, and is pressed on the inner needle valve seat by downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the inner needle valve return spring, and the outer needle valve body is pressed on the outer needle valve sleeve by downward hydraulic pressure of the diesel oil in the first control oil cavity and the elastic force of the outer needle valve return spring;

When the micro-injection mode is adopted, a second electromagnetic valve is electrified, a second armature iron drives a second valve rod to move upwards, a second ball valve is opened, diesel oil in a second control oil cavity flows out through a second oil outlet orifice to release pressure, and when the upward hydraulic pressure of the diesel oil in an inner needle valve pressure chamber is greater than the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of an inner needle valve return spring, the inner needle valve is opened to perform micro-injection of the diesel oil; when the medium oil injection mode is adopted, the first electromagnetic valve is electrified, the first armature iron drives the first valve rod to move upwards, the first ball valve is opened, diesel oil in the first control oil cavity flows out through the first oil outlet orifice to release pressure, and when the outer needle valve body is subjected to the upward hydraulic pressure of the diesel oil in the outer needle valve pressure chamber and is larger than the downward hydraulic pressure of the diesel oil in the first control oil cavity and the elastic force of the outer needle valve body reset spring, the outer needle valve body is opened to perform medium oil injection of the diesel oil; when a large oil injection mode is adopted, the first electromagnetic valve and the second electromagnetic valve are electrified at the same time, the inner needle valve body and the outer needle valve body are both opened to perform large oil injection of diesel oil, and the opening modes of the inner needle valve body and the outer needle valve body are respectively the same as the micro injection and medium oil injection processes; when the boot-type injection mode is adopted, the second electromagnetic valve is electrified, the inner needle valve body is opened to perform micro injection of diesel oil, the first electromagnetic valve is electrified, the outer needle valve body is opened to perform mass injection of diesel oil, and the detailed opening modes of the inner needle valve body and the outer needle valve body are respectively the same as those of the micro injection and the medium oil injection.

The invention has the advantages that:

1. the injector provided by the invention can be used as an integrated dual-fuel injector for injecting zero-carbon fuel and diesel oil, and also can be used as a variable injection rule injector for injecting diesel oil, has wide application, is provided with only two electromagnetic valves, is simple to process, occupies small space and is easy to realize.

2. The invention controls the sealing and opening of the first oil outlet orifice and the second oil outlet orifice through the first electromagnetic valve and the second electromagnetic valve respectively, thereby controlling the opening and closing of the outer needle valve body and the inner needle valve body respectively; thus, when the integrated dual-fuel injector is used for injecting the zero-carbon fuel and the diesel, the aim of independently controlling the injection processes of the zero-carbon fuel and the diesel on one injector can be realized; four injection modes of a micro-injection mode, a medium oil injection mode, a large oil injection mode and a boot-type injection mode can be realized when the variable injection law injector is used for injecting diesel oil; that is, the injector can meet the injection requirements of a plurality of advanced combustion modes in a diesel engine and a dual-fuel engine, and can effectively improve the carbon emission reduction and performance of the booster engine.

3. When the integrated dual-fuel injector is used for injecting the zero-carbon fuel and the diesel oil, the two electromagnetic valves still use the diesel oil as control oil, cavitation erosion at the ball valve can be effectively reduced, and one injector is used for injecting the zero-carbon fuel and the diesel oil, so that the problem that the two injectors are difficult to be arranged on a cylinder cover is effectively solved.

Drawings

FIG. 1 is a schematic diagram of the structure of the present invention;

FIG. 2 is a schematic view of a part of the structures of the first control oil chamber and the second control oil chamber;

fig. 3 is a schematic view of a part of the structures at the inner needle valve body and the outer needle valve body.

Reference numerals in the drawings: a sealing cap 1; a fuel inlet No. 2; middle block number 3; middle block number two 4; a third middle block 5; a metering orifice plate 6; a first electromagnetic valve 7; a first armature 8; a valve rod number one 9; a ball valve number one 10; a first oil outlet orifice 11; a solenoid valve 12; a second armature 13; a valve stem number two 14; a second ball valve 15; a second oil outlet orifice 16; a fuel inlet 17; a first oil inlet orifice 18; a first control oil chamber 19; an intermediate fuel passage 20; a plug 21; a second oil inlet orifice 22; a second control oil chamber 23; an inner needle valve body 24; an inner needle return spring 25; an outer needle valve body 26; an outer needle return spring 27; an outer needle sheath 28; an outer needle valve pressure chamber 29; an inner needle pressure chamber 30; an inner needle valve seat 31; an inner nozzle 32; an outer nozzle 33; a fastening sleeve 34; injector body 35.

Detailed Description

The invention is described in more detail below, by way of example, with reference to the accompanying drawings:

Referring to fig. 1 to 3, the present invention includes a first fuel inlet 2, a first solenoid valve 7, a first oil outlet orifice 11, a second solenoid valve 12, a second oil outlet orifice 16, a second fuel inlet 17, a first oil inlet orifice 18, a first control oil chamber 19, an intermediate fuel passage 20, a plug 21, a second oil inlet orifice 22, a second control oil chamber, an inner needle valve body 24, an inner needle return spring 25, an outer needle valve body 26, an outer needle return spring 27, an outer needle sleeve 28, an outer needle pressure chamber 29, an inner needle pressure chamber 30, an inner needle valve seat 31, an inner nozzle hole 32, an outer nozzle hole 33, a fastening sleeve 34, and an injector body 35; the sealing cap 1 is positioned at the uppermost end of the injector and encloses a pressure accumulation cavity with the injector body 35, a first-size middle block 3 is arranged below the injector body 35, a second-size electromagnetic valve 12 is arranged on the first-size middle block 3, a second-size armature 13 and a second-size oil outlet orifice 16 are respectively arranged below the second-size electromagnetic valve 12, the second-size middle block 4 is positioned below the first-size middle block 3, the first-size electromagnetic valve 7 is positioned on the second-size middle block 4, a first-size armature 8, a first-size valve rod 9, a first-size ball valve 10 and a first-size oil outlet orifice 11 are respectively arranged below the first-size electromagnetic valve 7, a third-size middle block 5 and a measuring orifice plate 6 are respectively arranged below the second-size middle block 4, a second-size control oil cavity is positioned between the third-size middle block 5 and the measuring orifice plate 6, an outer needle sleeve 28, an outer needle return spring 27 and an outer needle valve body 26 are respectively arranged below the measuring orifice plate 6, an inner pressure chamber 30 is arranged between the inner needle valve body 24 and the outer needle valve body 26, an inner orifice 32 is arranged at the lower end of the inner pressure chamber 30, an outer pressure chamber 29 is arranged between the outer needle valve body 26 and the outer needle valve sleeve 28, an outer pressure chamber 29 is respectively arranged between the outer needle valve body 26 and the needle valve sleeve 28, an outer pressure chamber 29 is arranged at the lower end of the needle valve chamber is the needle valve chamber and the needle valve body is respectively, and the outer pressure chamber is arranged at the inner pressure chamber is the needle pressure chamber and the needle valve chamber is respectively, and the needle valve chamber is respectively and the needle valve body is 20 and the pressure chamber is respectively and the needle valve chamber is respectively and the pressure chamber is 20 and the pressure chamber is respectively and is compressed by the pressure and is 20.

As can be seen from fig. 2, the fuel entering from the second fuel passage can enter the first control oil chamber 19 and the second control oil chamber through the first oil inlet orifice 18 and the second oil inlet orifice 22, respectively, and the plug 21 is provided to prevent the fuel in the second control oil chamber from entering the intermediate fuel passage 20.

As can be seen from fig. 3, the total aperture of the inner nozzle hole 32 is smaller than the total aperture of the outer nozzle hole 33, i.e., the inner nozzle hole 32 is used for micro-injection of fuel.

The invention can be used as an integrated dual fuel injector for injecting zero carbon fuel and diesel oil, and also can be used as a variable injection rule injector for injecting diesel oil.

When the present invention is used as an integrated dual fuel injector for injecting zero carbon fuel and diesel fuel, the zero carbon fuel enters the accumulator chamber from the fuel inlet No. 2 and then flows into the outer needle valve pressure chamber 29; diesel oil enters the injector through the second fuel inlet 17, one of the diesel oil enters the first control oil cavity 19 through the first oil inlet orifice 18, the other of the diesel oil enters the second control oil cavity through the second oil inlet orifice 22, the other of the diesel oil enters the inner needle valve body 24 through the middle fuel channel 20 and enters the inner needle valve pressure chamber 30, the inner needle valve body 24 is pressed on the inner needle valve seat 31 by downward hydraulic pressure of diesel oil in the second control oil cavity and elastic force of the inner needle valve return spring 25, and the outer needle valve body 26 is pressed on the outer needle valve sleeve 28 by downward hydraulic pressure of diesel oil in the first control oil cavity 19 and elastic force of the outer needle valve return spring 27, so that no fuel is injected at this time.

When the integrated dual fuel injector is used for injecting the zero-carbon fuel and the diesel, the diesel is used as a pilot fuel to be subjected to micro injection through the inner spray hole 32, the zero-carbon fuel is used as a main fuel to be subjected to mass injection through the outer spray hole 33, and the pressure fluctuation of the low-carbon fuel can be reduced to a great extent by the pressure accumulation cavity; if diesel oil needs to be injected, the second electromagnetic valve 12 is electrified, the second armature 13 drives the second valve rod 14 to move upwards, the second ball valve 15 is opened, diesel oil in the second control oil cavity flows out through the second oil outlet orifice 16 to release pressure, and when the upward hydraulic pressure of the diesel oil in the inner needle valve body 24 is greater than the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the reset spring of the inner needle valve body 24, the inner needle valve body 24 is opened to inject the diesel oil; if the zero carbon fuel needs to be injected, the first electromagnetic valve 7 is electrified, the first armature 8 drives the first valve rod 9 to move upwards, the first ball valve 10 is opened, diesel oil in the first control oil cavity 19 flows out through the first oil outlet orifice 11 to release pressure, and when the outer needle valve 26 is subjected to the upward hydraulic pressure of the low carbon fuel in the outer needle valve pressure chamber 29 to be greater than the downward hydraulic pressure of the diesel oil in the first control oil cavity 19 and the elastic force of the reset spring of the outer needle valve 26, the outer needle valve 26 is opened to inject the low carbon fuel; the injection timing and the injection duration of the diesel oil and the low-carbon fuel are not mutually influenced, the diesel oil can be injected together with the low-carbon fuel, the diesel oil can also be injected before or after the low-carbon fuel, and the injection strategy can be flexibly adjusted according to the actual engine operation condition.

When the invention is used as a variable injection rule injector for injecting diesel oil, the first fuel channel and the second fuel channel are both communicated with diesel oil, and the diesel oil entering from the first fuel channel immediately enters the outer needle valve pressure chamber 29; the diesel oil entering from the second fuel passage enters the first control oil cavity 19 through the first oil inlet orifice 18, enters the second control oil cavity through the second oil inlet orifice 22, enters the inner needle valve pressure chamber 30 through the middle fuel passage 20, the inner needle valve body 24 is pressed on the inner needle valve seat 31 by the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the inner needle return spring 25, and the outer needle valve body 26 is pressed on the outer needle valve sleeve 28 by the downward hydraulic pressure of the diesel oil in the first control oil cavity 19 and the elastic force of the outer needle return spring 27.

When the invention is used as a variable injection rule injector for injecting diesel oil, a micro injection mode, a medium oil injection mode, a large oil injection mode and a boot injection mode of the diesel oil can be realized; when the micro-injection mode is adopted, the second electromagnetic valve 12 is electrified, the second armature 13 drives the second valve rod 14 to move upwards, the second ball valve 15 is opened, diesel oil in the second control oil cavity flows out through the second oil outlet orifice 16 to release pressure, and when the internal needle valve body 24 receives that the upward hydraulic pressure of the diesel oil in the internal needle valve pressure chamber 30 is greater than the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the reset spring of the internal needle valve body 24, the internal needle valve body 24 is opened to perform micro-injection of the diesel oil; when the medium oil injection mode is adopted, the first electromagnetic valve 7 is electrified, the first armature 8 drives the first valve rod 9 to move upwards, the first ball valve 10 is opened, diesel oil in the first control oil cavity 19 flows out through the first oil outlet orifice 11 to release pressure, and when the outer needle valve body 26 receives that the upward hydraulic pressure of the diesel oil in the outer needle valve pressure chamber 29 is greater than the downward hydraulic pressure of the diesel oil in the first control oil cavity 19 and the elastic force of the reset spring of the outer needle valve body 26, the outer needle valve body 26 is opened to perform medium oil injection of the diesel oil; when the large oil injection mode is adopted, the first electromagnetic valve 7 and the second electromagnetic valve 12 are electrified at the same time, the inner needle valve body 24 and the outer needle valve body 26 are both opened to perform large oil injection of diesel oil, and the detailed working process of opening the inner needle valve body 24 and the outer needle valve body 26 is similar to the micro injection and medium oil injection processes respectively; when the boot injection mode is adopted, the second electromagnetic valve 12 is electrified, the inner needle valve body 24 is opened to perform micro injection, the first electromagnetic valve 7 is electrified, the outer needle valve body 26 is opened to perform mass injection, and the detailed working processes of opening the inner needle valve body 24 and the outer needle valve body 26 are respectively similar to the micro injection and medium oil injection processes.

Claims (9)

1. An injector with controllable injection strategy based on double valve control is characterized in that: the injector comprises an injector body, a first middle block, a second middle block, a third middle block, a metering orifice plate and an outer needle valve sleeve which are arranged from top to bottom, wherein the injector body, the first middle block, the second middle block, the third middle block, the metering orifice plate and the outer needle valve sleeve are fixed together through an external fastening sleeve, a first fuel inlet is arranged on injection gas, a second oil outlet device is arranged in the first middle block and the second middle block, a first oil outlet device is arranged in the second middle block and the third middle block, a second fuel inlet is arranged on the metering orifice plate, an outer needle valve body is arranged in the outer needle valve sleeve, and an inner needle valve body is arranged in the outer needle valve body.

2. A dual valve control injection strategy based controllable injector according to claim 1, characterized by: the second oil outlet device comprises a second electromagnetic valve, a second armature, a second valve rod and a second ball valve, wherein a second armature reset spring is arranged in the second electromagnetic valve, the bottom end of the second armature reset spring is propped against the second armature, two ends of the second valve rod are respectively positioned in the second armature and a second middle block, the second armature is fixed with the second valve rod, the second ball valve is connected to the lower part of the second valve rod, and a second oil outlet orifice is arranged in the second middle block below the second ball valve.

3. A dual valve control injection strategy based controllable injector according to claim 2, characterized by: the oil outlet device comprises an electromagnetic valve, an armature, a valve rod and a ball valve, wherein an armature reset spring is arranged in the electromagnetic valve, the bottom end of the armature reset spring is propped against the armature, two ends of the valve rod are respectively positioned in an armature and a third middle block, the armature is fixed with the valve rod, the lower part of the valve rod is connected with the ball valve, and an oil outlet orifice is arranged in a thirteenth middle block below the ball valve.

4. A dual valve control injection strategy based controllable injector according to claim 3, characterized by: an inner needle valve reset spring and a plug are arranged in the metering orifice plate, the upper end and the lower end of the inner needle valve reset spring are respectively provided with a third intermediate block and a plug, the top of the inner needle valve body is positioned below the plug, the outer needle valve is sleeved outside the inner needle valve body, the two ends of the outer needle valve reset spring are respectively provided with the metering orifice plate and the outer needle valve body, the middle part of the inner needle valve body is provided with a middle fuel channel which is communicated with a second fuel inlet, a first control oil cavity is formed between the metering orifice plate and the outer needle valve body below the metering orifice plate, the position of the inner needle valve reset spring forms a second control oil cavity, a first oil inlet orifice and a second oil inlet orifice are respectively arranged in the metering orifice plate, the first oil inlet orifice is respectively communicated with the second fuel inlet and the first control oil cavity, and the second oil inlet orifice is respectively communicated with the second fuel inlet and the second control oil cavity; the first oil outlet orifice is communicated with the first control oil cavity, and the second oil outlet orifice is communicated with the second control oil cavity.

5. A dual valve control injection strategy based controllable injector according to claim 1, characterized by: an outer needle valve sleeve and an outer needle valve body are arranged between the outer needle valve sleeve and the outer needle valve body, an inner needle valve pressure chamber is formed between the outer needle valve body and the inner needle valve body, the inner needle valve pressure chamber is communicated with an intermediate fuel channel, the outer needle valve pressure chamber is communicated with a first fuel inlet, an inner needle valve seat matched with the inner needle valve body is arranged at the bottom of the outer needle valve body, inner spray holes are arranged on the inner needle valve seat, and outer spray holes are arranged at the bottom of the outer needle valve sleeve.

6. A dual valve control injection strategy based controllable injector according to claim 1, characterized by: the injection gas is internally provided with an accumulation cavity, a first fuel inlet is communicated with the accumulation cavity, and a sealing cap is arranged at the top of the accumulation cavity.

7. The dual valve control injection strategy controllable injector of claim 5, wherein: the total aperture of the inner spray hole is smaller than that of the outer spray hole, namely the inner spray hole is used for micro-injection of fuel, and the outer spray hole is used for mass injection.

8. A dual valve control injection strategy based controllable injector according to claim 1, characterized by: the first fuel inlet is filled with zero carbon fuel so as to enter an accumulation cavity and an outer needle valve pressure chamber, the second fuel inlet is filled with diesel oil, one path of the fuel enters a first control oil cavity through a first oil inlet orifice, the other path of the fuel enters a second control oil cavity through a second oil inlet orifice, the other path of the fuel enters an inner needle valve pressure chamber through an intermediate fuel channel, an inner needle valve body is pressed on an inner needle valve seat by downward diesel oil hydraulic pressure in the second control oil cavity and elastic force of an inner needle valve return spring, and an outer needle valve body is pressed on an outer needle valve sleeve by downward diesel oil hydraulic pressure in the first control oil cavity and elastic force of the outer needle valve return spring;

Diesel oil is used as a pilot fuel to carry out micro injection through an inner jet orifice, and zero carbon fuel is used as a main fuel to carry out mass injection through an outer jet orifice; if the diesel oil is injected, the second electromagnetic valve is electrified, the second armature iron drives the second valve rod to move upwards, the second ball valve is opened, the diesel oil in the second control oil cavity flows out through the second oil outlet orifice to release pressure, and when the upward hydraulic pressure of the diesel oil in the inner needle valve pressure chamber is greater than the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the inner needle valve return spring, the inner needle valve is opened to inject the diesel oil; if the zero carbon fuel is to be injected, the first electromagnetic valve is electrified, the first armature iron drives the first valve rod to move upwards, the first ball valve is opened, diesel oil in the first control oil cavity flows out through the first oil outlet orifice to release pressure, and when the outer needle valve body is subjected to the fact that the upward hydraulic pressure of the low carbon fuel in the outer needle valve pressure chamber is greater than the downward hydraulic pressure of the diesel oil in the first control oil cavity and the elastic force of the outer needle valve body reset spring, the outer needle valve body is opened to inject the low carbon fuel.

9. A dual valve control injection strategy based controllable injector according to claim 1, characterized by: the first fuel channel and the second fuel channel are communicated with diesel oil, and the diesel oil entering from the first fuel channel immediately enters the outer needle valve pressure chamber; the diesel oil entering from the second fuel channel enters the first control oil cavity through the first oil inlet orifice, enters the second control oil cavity through the second oil inlet orifice, enters the inner needle valve pressure chamber through the middle fuel channel, and is pressed on the inner needle valve seat by downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of the inner needle valve return spring, and the outer needle valve body is pressed on the outer needle valve sleeve by downward hydraulic pressure of the diesel oil in the first control oil cavity and the elastic force of the outer needle valve return spring;

When the micro-injection mode is adopted, a second electromagnetic valve is electrified, a second armature iron drives a second valve rod to move upwards, a second ball valve is opened, diesel oil in a second control oil cavity flows out through a second oil outlet orifice to release pressure, and when the upward hydraulic pressure of the diesel oil in an inner needle valve pressure chamber is greater than the downward hydraulic pressure of the diesel oil in the second control oil cavity and the elastic force of an inner needle valve return spring, the inner needle valve is opened to perform micro-injection of the diesel oil; when the medium oil injection mode is adopted, the first electromagnetic valve is electrified, the first armature iron drives the first valve rod to move upwards, the first ball valve is opened, diesel oil in the first control oil cavity flows out through the first oil outlet orifice to release pressure, and when the outer needle valve body is subjected to the upward hydraulic pressure of the diesel oil in the outer needle valve pressure chamber and is larger than the downward hydraulic pressure of the diesel oil in the first control oil cavity and the elastic force of the outer needle valve body reset spring, the outer needle valve body is opened to perform medium oil injection of the diesel oil; when a large oil injection mode is adopted, the first electromagnetic valve and the second electromagnetic valve are electrified at the same time, the inner needle valve body and the outer needle valve body are both opened to perform large oil injection of diesel oil, and the opening modes of the inner needle valve body and the outer needle valve body are respectively the same as the micro injection and medium oil injection processes; when the boot-type injection mode is adopted, the second electromagnetic valve is electrified, the inner needle valve body is opened to perform micro injection of diesel oil, the first electromagnetic valve is electrified, the outer needle valve body is opened to perform mass injection of diesel oil, and the detailed opening modes of the inner needle valve body and the outer needle valve body are respectively the same as those of the micro injection and the medium oil injection.