CN210068342U

CN210068342U - Gas fuel injection system

Info

Publication number: CN210068342U
Application number: CN201920564877.1U
Authority: CN
Inventors: 张建明; 姬广存
Original assignee: Yingjia Power Technology Wuxi Co Ltd
Current assignee: Yingjia Power Technology Wuxi Co Ltd
Priority date: 2019-04-24
Filing date: 2019-04-24
Publication date: 2020-02-14
Anticipated expiration: 2029-04-24

Abstract

The utility model belongs to the technical field of internal-combustion engine fuel injection system, concretely relates to gas fuel injection system. This gaseous fuel injection system, including sprayer, oil tank, two three-way valves, hydraulic pressure rail and gas rail, the through-hole and the gas rail intercommunication of intercommunication on the gas pocket on the sprayer passes through the midbody, and the needle valve control chamber that the sprayer is located the valve body passes through the inlet port and the two three-way valve intercommunication of intercommunication on the midbody, two three-way valves and oil tank and hydraulic pressure rail intercommunication, gas rail and hydraulic pressure rail are through balanced valve and air supply intercommunication respectively. The beneficial effects are as follows: the heat efficiency is high, the fuel consumption is low, and the requirements of higher and higher emission standards can be met; the compressed natural gas can be accurately sprayed at regular time, quantitatively and repeatedly; the structure is simple, the processing is convenient, and the production cost is reduced; the storage of the liquefied natural gas can greatly increase the endurance mileage of the vehicle, and provides favorable conditions for the popularization of the natural gas engine.

Description

Gas fuel injection system

Technical Field

The utility model belongs to the technical field of internal-combustion engine fuel injection system, concretely relates to gas fuel injection system.

Background

In a conventional vehicle power system, liquid fuels such as gasoline and diesel oil are mostly used as combustion media, and natural gas is partially used as fuel.

The latest high pressure common rail injection technology is adopted for diesel internal combustion engines, and the injected diesel oil is directly injected into a combustion chamber of the engine to be combusted in a state of tiny particles, the tiny particles cannot be completely combusted, and partial PM particles are discharged to the air. Diesel internal combustion engines also emit large amounts of environmentally polluting gases such as NOx, COx, SOx, etc. during combustion. In order to reduce the emission of pollutant gases and PM particles, a plurality of post-treatment modes such as DOC, SCR, DPF and the like are required, the structure is complex, and the cost is high. The emission standard of the national six is realized, the limit of the emission of the diesel engine is reached, and the diesel engine is difficult to meet the requirement of higher emission standard. And the diesel oil is a non-renewable resource, and the sustainable supply of energy cannot be ensured.

In the gasoline internal combustion engine, high-pressure direct injection cannot be performed during combustion, only low-pressure combustion can be performed after premixing fuel and air, the compression ratio is low, the thermal efficiency is low, and a large amount of environmentally polluting gases such as NOx, COx, SOx, and the like and PM particles are emitted along with the combustion of gasoline, thereby polluting the environment. Gasoline is also a non-renewable resource and cannot ensure the sustainable supply of energy.

A small amount of natural gas internal combustion engines existing in the market are all injected through air passages, ignition devices are adopted at air inlet manifolds to ignite natural gas, the compression ratio of the engine is low, the heat efficiency is low, the natural gas enters an air cylinder along with air, the natural gas enters gaps of the air cylinder in the compression process, the natural gas (CH 4) in the gaps cannot be burnt and is directly discharged, and air pollution can be caused.

With the development of science and technology, a direct injection technology of a natural gas internal combustion engine is developed at present, compressed natural gas is injected near a top dead center of compression when the internal combustion engine works, and the natural gas is ignited by an ignition device to perform combustion work. The compressed natural gas direct injection technology has high compression ratio, high heat efficiency and low fuel consumption, and can meet the requirements of power and energy consumption. The main component of natural gas is methane (CH 4), and the products of combustion are mainly carbon dioxide and water, thus greatly reducing the emission of NOx, COx, SOx and other gases polluting the environment and PM particles. The natural gas can be prepared in an artificial mode, is renewable resources, and can ensure sustainable supply of energy. The development of the compressed natural gas direct injection technology draws attention from all countries in the world. The german group of public age has begun to develop the technology of direct injection of compressed natural gas, and by 2025, about 2000 CNG gas filling stations are built in germany, so that the supply amount is increased to be available for millions of compressed natural gas vehicles.

At present, natural gas direct injection internal combustion engines in the market are still in the research and development test stage, and a mature technical route is not formed. The natural gas injection system has a complex structural design and high production cost, and the injection system has large fluctuation when controlling the injection amount of the compressed natural gas. Gaseous fuel needs to occupy great volume when the storage, when being applied to vehicle power, often faces the short problem of continuation of the journey mileage, if store gaseous fuel with the liquefaction form, the volume that occupies when will significantly reduce storing increases the continuation of the journey mileage of vehicle.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a remedy prior art's defect, provide a fuel consumption is low, processing convenient gas fuel injection system.

The utility model discloses a realize through following technical scheme:

the utility model provides a gaseous fuel injection system, includes sprayer, oil tank, two three-way valves, hydraulic pressure and shares rail and gas rail, the through-hole and the gas rail intercommunication of intercommunication on the gas pocket on the sprayer passes through the midbody, and the needle valve control chamber that the sprayer is located the valve body passes through the inlet port and the two three-way valve intercommunication of intercommunication on the midbody, two three-way valves and oil tank and hydraulic pressure share rail intercommunication, gas rail and hydraulic pressure share rail communicate with the air supply through balanced valve respectively.

Further, a high-pressure pump and a booster pump are communicated between the oil tank and the hydraulic common rail.

Further, the gas source includes liquefied natural gas and compressed natural gas.

Further, the liquefied natural gas is stored to the LNG tank, the LNG tank is communicated with the vaporizer through the low-temperature pump and the stop valve and the pressure release valve, and the vaporizer is communicated with the balance valve through the buffer.

Further, the LNG tank is provided with a vent valve, the LNG tank and the vaporizer are communicated with a supercharger, a one-way valve is arranged on a pipeline communicated with the supercharger, and a pressure converter is arranged on a pipeline communicated with the vaporizer.

Further, the CNG jar is through CNG jar storage, CNG jar through balanced valve respectively with hydraulic pressure common rail and gas rail intercommunication.

The utility model has the advantages that: the gas fuel injection system is a direct injection technology of compressed natural gas, the compression ratio of an engine is high, the heat efficiency is high, the fuel consumption is low, and the requirements of higher and higher emission standards can be met; the gas fuel injection system controls the opening and closing of the needle valve through the two-position three-way valve, so that the injection time and the injection quantity of the natural gas are controlled, and the compressed natural gas can be accurately injected at regular time, quantitatively and for multiple times; the common rail injection technology is continued, the structure is simple, the processing is convenient, and the production cost is reduced; the storage of the liquefied natural gas can greatly increase the endurance mileage of the vehicle, and provides favorable conditions for the popularization of the natural gas engine.

Drawings

The present invention will be further described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of the operation of a liquefied natural gas fuel injection system according to the present invention;

figure 2 is the utility model discloses a compressed natural gas's gaseous fuel injection system working principle diagram.

In the figure, a 001 injector, a valve body 1, a needle valve 2, a middle body 3, a needle valve spring 4, an injection cavity 5, a gas hole 6, a needle valve control cavity 7, an oil inlet hole 8, a fuel tank 9, a spray hole 10, a two-position three-way valve 11, a first channel 12, a second channel 13, a third channel 14, a booster pump 15, a high-pressure pump 16, a hydraulic common rail 17, a gas rail 18, a balance valve 19, a buffer 20, a vaporizer 21, a pressure converter 22, a pressure relief valve 23, a stop valve 24, a supercharger 25, a low-temperature pump 26, a check valve 27, an LNG tank 28, a bleed valve 29 and a CNG tank.

Detailed Description

Fig. 1 and 2 show an embodiment of the present invention. The utility model discloses a gaseous fuel injection system, including sprayer 001, oil tank 9, two three-way valve 11, hydraulic pressure rail 17 and gas rail 18, through-hole and the gas rail 18 intercommunication of intercommunication on the gas pocket 6 on the sprayer 001 passes through midbody 3, and the needle valve control chamber 7 that sprayer 001 is located on valve body 1 communicates with two three-way valve 11 through the inlet port 8 of intercommunication on midbody 3, two three-way valve 11 and oil tank 9 and hydraulic pressure rail 17 intercommunication, gas rail 18 and hydraulic pressure rail 17 communicate with the air supply through balanced valve 19 respectively.

Further, a high-pressure pump 16 and a booster pump 15 are communicated between the oil tank 9 and the common rail 17.

Further, the liquefied natural gas is stored in the LNG tank 28, the LNG tank 28 is communicated with the vaporizer 21 through the shutoff valve 24 and the relief valve 23 by the cryogenic pump 26, and the vaporizer 21 is communicated with the equilibrium valve 19 by the buffer 20.

Further, a release valve 29 is arranged on the LNG tank 28, a booster 25 is communicated between the LNG tank 28 and the vaporizer 21, a check valve 27 is arranged on a pipeline through which the LNG tank 28 is communicated with the booster 25, and a pressure converter 22 is arranged on a pipeline through which the booster 25 is communicated with the vaporizer 21.

Further, the compressed natural gas is stored by a CNG tank 30, and the CNG tank 30 is communicated with the hydraulic common rail 17 and the gas rail 18 through a balance valve 19, respectively.

The utility model discloses a gaseous fuel injection system sets up cryopump 26, pumps the liquefied natural gas in LNG jar 28, carries to vaporizer 21, and in vaporizer 21, liquefied natural gas converts the CNG into, stores in buffer 20.

In the gas fuel injection system, a booster 25 is provided, and the compressed natural gas in the vaporizer 21 is converted by the pressure converter 22 and then introduced into the booster 25. When the pressure in the LNG tank 28 is low, the compressed natural gas in the pressure booster 25 pushes the check valve 27 to open, and the compressed natural gas enters the LNG tank 28 to boost the pressure of the LNG tank 28. When the pressure in the LNG tank 28 is excessive, the purge valve 29 is opened to reduce the pressure in the LNG tank 28.

In the gas fuel injection system, a shutoff valve 24 and a relief valve 23 are provided between a cryopump 26 and a carburetor 21, and the shutoff valve 24 is closed when the engine stops operating. When the pressure in the line is excessive, the pressure relief valve 23 opens. When the liquefied natural gas between the shutoff valve 24 and the vaporizer 21 is vaporized while the shutoff valve 24 is closed, the vaporized high-pressure gas is discharged from the relief valve 23.

In the gas fuel injection system, a balance valve 19 is arranged, and compressed natural gas and hydraulic oil in the hydraulic common rail 17 are both introduced into the balance valve 19, so that the compressed natural gas and the hydraulic oil are stabilized within a specified pressure difference range, and the accuracy of compressed natural gas injection control is ensured.

In the gas fuel injection system, the liquid in the oil tank 9 may be diesel oil, engine oil, hydraulic oil or other liquid with controllable pressure, and for convenience, the liquid is described as hydraulic oil. The hydraulic oil in the oil tank 9 is pressurized by a booster pump 15 and then delivered to a high-pressure pump 16, and the pressurized hydraulic oil is pumped to a hydraulic common rail 17.

When the engine works, the cryogenic pump 26 pumps out the liquefied natural gas from the LNG tank 28, the liquefied natural gas is gasified by the gasifier 21, the buffer 20 is stable, the balance valve 19 is balanced, and then the compressed natural gas is delivered to the gas rail 18 and is delivered to the injection cavity 5 in the injector 001 through the pipeline and the gas hole 6. The booster pump 15 pumps the hydraulic oil out of the oil tank 9, the hydraulic oil is pressurized by the high-pressure pump 16 and then is conveyed to the hydraulic common rail 17, and the hydraulic oil is conveyed to the needle valve control cavity 7 through the pipeline, the two-position three-way valve 11 and the oil inlet 8. When the two-position three-way valve 11 is powered off, the first channel 12 is connected with the third channel 14, the resultant force of the hydraulic pressure at the upper end of the needle valve 2 and the spring force of the needle valve spring 4 is larger than the air pressure at the lower end of the needle valve 2, and the needle valve 2 is tightly pressed on the sealing conical surface in the valve body 1. When the two-position three-way valve 11 is electrified, the first channel 12 is communicated with the second channel 13, hydraulic oil in the needle valve control cavity 7 flows into the oil tank 9, the pressure in the needle valve control cavity 7 is rapidly reduced, when the resultant force of the upper hydraulic pressure of the needle valve 2 and the spring force is smaller than the lower air pressure of the needle valve 2, the needle valve 2 moves upwards, the injection cavity 5 is communicated with the injection hole 10, compressed natural gas is injected into an engine combustion chamber through the injection hole 10, and after the compressed natural gas is ignited by the ignition device, the engine combusts to do work. When the two-position three-way valve 11 is powered off, the first channel 12 is connected with the third channel 14, the hydraulic pressure in the needle valve control cavity 7 is rapidly increased, the resultant force of the hydraulic pressure at the upper end of the needle valve 2 and the spring force is larger than the pneumatic pressure at the lower end of the needle valve 2, the needle valve 2 moves downwards until the needle valve 2 is tightly pressed on the sealing conical surface in the valve body 1, the injection cavity 5 is isolated from the injection hole 10, and the compressed natural gas stops being injected.

The utility model relates to an among the gas fuel injection system, the natural gas not only can be stored with the liquefied natural gas mode, can also be stored with the CNG mode. The compressed natural gas is stored in the CNG tank 30, and when the engine is operated, the compressed natural gas in the CNG tank 30 is balanced by the balance valve 19 and then delivered to the gas rail 18, and the operation principle of the injection system is the same as the above description.

The present invention is not limited to the above embodiments, and any person should learn to make under the teaching of the present invention and the present invention has the same or similar technical solution, and all fall into the protection scope of the present invention.

The technology, shape and construction parts which are not described in detail in the present invention are all known technology.

Claims

1. The utility model provides a gaseous fuel injection system, includes sprayer, oil tank, two three-way valves, hydraulic pressure and shares rail and gas rail, its characterized in that, through-hole and the gas rail intercommunication of intercommunication on the gas pocket on the sprayer passes through the midbody, and the needle valve control chamber that the sprayer is located the valve body passes through the inlet port and the two three-way valve intercommunication of intercommunication on the midbody, two three-way valves and oil tank and hydraulic pressure share rail intercommunication, gas rail and hydraulic pressure share rail communicate with the air supply through balanced valve respectively.

2. A gaseous fuel injection system according to claim 1, wherein: and a high-pressure pump and a booster pump are communicated between the oil tank and the hydraulic common rail.

3. A gaseous fuel injection system according to claim 1, wherein: the gas source includes liquefied natural gas and compressed natural gas.

4. A gaseous fuel injection system according to claim 3, wherein: the liquefied natural gas is stored in the LNG tank, the LNG tank is communicated with the vaporizer through the low-temperature pump and the stop valve and the pressure release valve, and the vaporizer is communicated with the balance valve through the buffer.

5. A gaseous fuel injection system according to claim 4, wherein: the LNG tank is provided with a vent valve, the LNG tank and the vaporizer are communicated with each other through a supercharger, a one-way valve is arranged on a pipeline through which the LNG tank is communicated with the supercharger, and a pressure converter is arranged on a pipeline through which the supercharger is communicated with the vaporizer.

6. A gaseous fuel injection system according to claim 3, wherein: the CNG tank is communicated with the hydraulic common rail and the gas rail through the balance valve.