CN109184986A

CN109184986A - The variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic

Info

Publication number: CN109184986A
Application number: CN201810834620.3A
Authority: CN
Inventors: 范立云; 白云
Original assignee: Harbin Engineering University
Current assignee: Harbin Engineering University
Priority date: 2018-07-26
Filing date: 2018-07-26
Publication date: 2019-01-11
Anticipated expiration: 2038-07-26
Also published as: CN109184986B

Abstract

The purpose of the present invention is to provide the pressure accumulation type electric control fuel oil jet systems that fuel injection characteristic can be changed, including common rail pipe, high-pressure oil pipe, high-pressure oil pump, filter, fuel tank, oil return pipe and fuel injector.The present invention uses two-stage electromagnetic valve arrangement, controls the pressurization area of three-level piston, different pressure ratios can be effectively realized, so that fuel injection characteristic is more flexible；Pressure accumulation chamber can slowing oil injection when caused pressure oscillation, be conducive to the accurate control to distributive value, it is remarkably improved especially for the control precision of small oil mass, the pressure stabilization function of pressure accumulation chamber reduces the size of common rail pipe, so that the service life of common rail pipe extends；AND DEWATERING FOR ORIFICE STRUCTURE is provided in pressure accumulation chamber simultaneously, the throttle orifice of different pore size is drilled on orifice plate, play the role of throttling and filtering to the fuel oil for flowing to fuel injector high-pressure oil pipe from pressure accumulation chamber, to reduce the pressure oscillation of fuel injector intermediate fuel oil, circulating fuel injection quantity fluctuation is reduced, high-pressure common-rail fuel system multi-injection process is more accurately controlled.

Description

The variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic

Technical field

The present invention relates to a kind of diesel engines, specifically diesel fuel system.

Background technique

Diesel fuel injection system is the core component of diesel engine, and the quality of diesel engine combustion quality is largely The upper performance depending on fuel injection system.The guideline for organizing diesel engine ideal combustion process is to inhibit initiation combustion, is added Fast mid-term burning, reduction after-burning, high after wanting first low this requires the injection rate of electric-controlled fuel injector, end oil spout is quick, oil spout Duration is moderate, but for existing electric control fuel oil jet system, realizes that above-mentioned course of injection can greatly increase control Difficulty.

Electromagnetic control type fuel injector applied to Electronic Control for Fuel Injection System of Diesel Engine is responded compared to positive injector Faster, injection characteristics are flexibly controllable for speed, also more accurate to the control of distributive value.Although electromagnetic control type fuel injector is to diesel oil The emission performance of machine makes moderate progress, but there is also some shortcomings: fuel injector generallys use the form of single channel oil inlet, and needle-valve is taken a seat Response speed is slow, and the equilibrium relation due to passing in and out oilhole aperture, it is desirable to it is more difficult to further increase response characteristic；Two two The dynamic recirculating oil quantity of the form of port valve is larger, influences fuel utilization ratio；Axial gap between needle-valve and control plunger causes to spray There is static leakage fuel oil in oily device；Under big oil mass spray regime, under the uniformity and stability of each cylinder injection process Drop etc..

Summary of the invention

The purpose of the present invention is to provide be able to achieve to control pressure ratio flexibly to reach the fuel injection characteristic of different jeting effects Variable pressure accumulation type electric control fuel oil jet system.

The object of the present invention is achieved like this:

The variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic of the present invention, it is characterized in that: including fuel injector, common rail Pipe, high-pressure oil pipe, fuel tank, high-pressure oil pump, oil return pipe；

The fuel injector includes oil injector body, pressure accumulation cavity wall, pressurization control valve portion, three-level piston component, Injection Control Valve portion, needle-valve portion, pressurization control valve portion and three-level piston are mounted in oil injector body from top to bottom, Injection Control valve portion Divide and needle-valve portion is arranged in from top to bottom in the tight cap of nozzle, tight cap of spraying nozzle is fixed below oil injector body, and pressure accumulation cavity wall is fixed Pressure accumulation chamber and high-pressure oil passage are set in supercharger control valve upper, pressure accumulation cavity wall, and pressure accumulation chamber is connected to high-pressure oil passage；

The pressurization control valve portion includes supercharger control valve upper valve base, supercharger control valve centre valve seat, dual-coil electromagnetic valve limit Position orifice plate, charged piston limit orifice plate, supercharger control valve valve rod, level-one armature, second level armature, bacterium shape sleeve, supercharger control valve Valve seat, dual-coil electromagnetic valve limit orifice plate and charged piston limit orifice plate are arranged from top to bottom among upper valve base, supercharger control valve, are pressurized The head of control valve valve rod, which is located at, limits the supercharger control valve valve chamber that orifice plate and charged piston limit orifice plate are constituted by dual-coil electromagnetic valve In, external is bacterium shape sleeve, and second level armature, the middle part installation of supercharger control valve valve rod are installed in the tail portion of supercharger control valve valve rod Level-one armature, second level armature are located among supercharger control valve in valve seat, and level-one armature is located in dual-coil electromagnetic valve limit orifice plate, pressurization Two-stage electromagnetic iron coil is wound in control valve upper valve base, winds level-one electromagnet coil, pressurization among supercharger control valve in valve seat Supercharger control valve valve rod reset spring, pressurization control are set between control valve valve rod tail portion and supercharger control valve upper valve base above it The part that valve valve rod processed is located at below level-one armature is cased with level-one armature fixed spring, the extension of bacterium shape sleeve and lower section Charged piston, which limits, is arranged bacterium shape sleeve spring between orifice plate, the head of supercharger control valve valve rod is machined with T-type way to cycle oil, T Type way to cycle oil includes the vertical access communicated and cross walkway, and dual-coil electromagnetic valve limits setting pressurization throttle orifice, second level on orifice plate Pressure Increasing Oil-Line, charged piston, which limits, is arranged level-one Pressure Increasing Oil-Line and low pressure oil leak hole on orifice plate, pressurization throttle orifice, two-stage supercharging oil Road, level-one Pressure Increasing Oil-Line are connected to supercharger control valve valve chamber with low pressure oil leak hole, are pressurized the other end connection high pressure oil of throttle orifice Road, low pressure oil leak hole are connected to fuel tank；

The three-level piston component includes charged piston, piston return spring, and charged piston is three-level stepped cylinder structure, It is respectively from top to bottom the first-third cylinder, and diameter successively decreases, the first cylinder and the charged piston above it limit between orifice plate Form plunger shaft, plunger shaft limits the hole in orifice plate by charged piston and is connected to high-pressure oil passage, the first cylinder and the second cylinder and Level-one booster cavity is formed between oil injector body, and two-stage supercharging chamber is formed between the second cylinder and third cylinder and oil injector body, the Three-level booster cavity is formed between three cylinders and oil injector body below, and piston return spring, level-one are installed in three-level booster cavity Booster cavity is connected to level-one Pressure Increasing Oil-Line, and two-stage supercharging chamber is connected to two-stage supercharging oil circuit, and three-level booster cavity is connected to high by check valve Pressure oil road, three-level booster cavity lower part are provided with Pressure Increasing Oil-Line；

The Injection Control valve portion includes injector control valve upper valve base, injector control valve limit orifice plate, intermediate orifice plate, spray Oil control valve valve rod, armature, injector control valve upper valve base, injector control valve limit orifice plate and intermediate orifice plate are arranged from top to bottom, The setting of injector control valve valve rod limits in orifice plate in injector control valve, and armature is installed on the top of injector control valve valve rod, armature with Injector control valve valve rod return spring, injector control valve valve rod return spring are installed between the injector control valve upper valve base above it Electromagnet coil is wound in external injector control valve upper valve base, and low pressure oil leak hole, oil spout control are set in injector control valve valve rod Valve limit orifice plate processed and intermediate orifice plate constitute injector control valve valve chamber, and injector control valve stem lower portion includes tapered protrusion, oil spout Control valve, which limits, is arranged injector control valve in-line on orifice plate, injector control valve in-line connection high-pressure oil passage, on intermediate orifice plate Oil inlet metering-orifice is set, and oil inlet metering-orifice is connected to injector control valve valve chamber；

The needle-valve portion includes needle-valve limit orifice plate, nozzle, needle-valve limit orifice plate and during nozzle is arranged in from top to bottom Between below orifice plate, fluid power compensating piston epicoele in-line, non-return passage are set in intermediate orifice plate, non-return is installed in non-return passage Valve, fluid power compensating piston epicoele in-line are connected to high-pressure oil passage, and non-return passage is connected to oil inlet metering-orifice, is arranged in needle-valve limit orifice plate Fluid power compensating piston, control chamber oil circuit are cased with fluid power compensating piston reset spring, fluid power compensating piston outside fluid power compensating piston The upper end of reset spring is withstood on fluid power compensating piston, and the lower end of fluid power compensating piston reset spring withstands on the limit of needle-valve below On the orifice plate of position, the fluid power compensating piston epicoele communicated with fluid power compensating piston epicoele in-line is formed above fluid power compensating piston, Fluid power compensating piston reset spring present position is fluid power compensating piston cavity of resorption, fluid power compensating piston lower end and needle-valve below It limits and forms fluid power compensating piston draining chamber, control chamber oil communication oil inlet metering-orifice between orifice plate；Needle-valve, needle-valve are installed in nozzle Top is cased with needle-valve reset spring, and the upper end of needle-valve reset spring is withstood on needle-valve limit orifice plate, the lower end of needle-valve reset spring It withstands on needle-valve, needle-valve reset spring present position is control chamber, and control chamber is connected to control chamber oil circuit, oil holding slot is arranged in nozzle In-line, forms oil holding slot between needle-valve and nozzle, nozzle bottom is arranged spray orifice, oil holding slot in-line be respectively communicated with oil holding slot and Pressure Increasing Oil-Line, fluid power compensating piston cavity of resorption are connected to the non-return passage below check-valves, fluid power by fluid power compensating piston in-line Compensating piston cavity of resorption is connected to control chamber by fluid power compensating piston vent line；

Fuel inlet above the pressure accumulation cavity wall of fuel injector is connected to the hydraulic oil outlet of common rail pipe, fuel tank by high-pressure oil pipe The hydraulic oil inlet of common rail pipe is connected to by filter, high-pressure oil pump, the low pressure oil return opening of fuel injector is connected to fuel tank, the number of fuel injector It measures consistent with the number of cylinders of diesel engine.

The present invention may also include:

1, the fuel injector, under no boost mode, pressurization control valve portion no power, check valve is opened；Work as Injection Control When valve portion is powered, electromagnet attracts armature, and armature drives injector control valve valve rod to move upwards by conical surface seal and to beat Low pressure oil leak hole is opened, the fuel oil in control chamber enters electromagnetism valve chamber by the low pressure oil leak hole in injector control valve valve rod, then It is returned in low-pressure reservoir by the low pressure oil way being arranged in electromagnetism valve chamber, fluid power compensating piston moves downward, and check-valves closes It closes, fluid power compensating piston is by the fuel-displaced road direction control chamber repairing of fluid power compensating piston, when the pressure and needle valve spring in control chamber The resultant force that is formed of elastic force when being less than the upward hydraulic coupling of fuel oil in oil holding slot, needle-valve is lifted up, and spray orifice is opened；When oil spout control When valve portion processed powers off, injector control valve valve rod is taken a seat under the elastic force effect of injector control valve valve rod return spring, will be low High-pressure oil passage is opened while pressing draining bore closure, check-valves is opened, and control chamber passes through under oil inlet metering-orifice and fluid power compensating piston Chamber builds pressure again, when the resultant force that the elastic force of pressure and needle valve spring in control chamber is formed is greater than the liquid that fuel oil is upward in oil holding slot When pressure, needle-valve drops back into one's seat.

2, the fuel injector, under low pressure charging mode, the level-one electromagnet coil power of pressurization control valve portion, level-one electromagnetism Iron attracts level-one armature, and level-one armature drives supercharger control valve valve rod to move upward to level-one electromagnet spacing place；Bacterium shape sleeve As supercharger control valve valve rod is lifted up under the action of bacterium shape sleeve spring power, low pressure oil leak hole is opened, until by bacterium Conical surface seal above shape sleeve.Fuel oil in level-one booster cavity flows through low pressure oil leak hole by level-one Pressure Increasing Oil-Line and returns to low pressure In fuel tank, charged piston is moved downward, the closed check valve at the oil inlet of three-level booster cavity；Subsequent Injection Control valve portion is logical Electricity, electromagnet attract armature, and armature drives injector control valve valve rod to move upwards by conical surface seal and to open low pressure draining Hole, the fuel oil in control chamber are flowed back in low-pressure reservoir by low pressure oil leak hole, and fluid power compensating piston moves downward, and check-valves closes It closes, fluid power compensating piston is by the fuel-displaced road direction control chamber repairing of fluid power compensating piston, when the conjunction of control cavity pressure and needle valve spring When power is less than that fuel oil is to the hydraulic coupling of needle-valve in oil holding slot, needle-valve is lifted up, and spray orifice is opened；When Injection Control valve portion powers off When, injector control valve valve rod is taken a seat under the elastic force effect of injector control valve valve rod return spring, by low pressure draining bore closure While open high-pressure oil passage, check-valves is opened, and control chamber builds pressure by oil inlet metering-orifice and fluid power compensating piston cavity of resorption again, when When the resultant force that the elastic force of pressure and needle valve spring in control chamber is formed is greater than the upward hydraulic coupling of fuel oil in oil holding slot, needle-valve weight Newly take a seat；When the power-off of pressurization control valve portion, spring-force driven dual of the supercharger control valve valve rod in supercharger control valve reset spring Lower drive bacterium shape sleeve is taken a seat together, and the conical surface seal of bacterium shape sleeve upper end is opened while by low pressure draining bore closure, high Compression ignition oil reenters level-one booster cavity by level-one Pressure Increasing Oil-Line, and charged piston is back up into initial position, and check valve is again It opens, fuel oil is entered in three-level booster cavity by check valve and enters back into oil holding slot.

3, the fuel injector, under high pressure-charging mode, the level-one electromagnet coil power of pressurization control valve portion first, level-one Electromagnet attracts level-one armature, and level-one armature drives supercharger control valve valve rod to move upward to level-one electromagnet spacing place；Bacterium shape Sleeve under the action of bacterium shape sleeve spring power as supercharger control valve valve rod is lifted up, until by the cone above bacterium shape sleeve Low pressure oil leak hole is opened while face seals；The fuel oil in level-one booster cavity flows through low pressure draining by level-one Pressure Increasing Oil-Line at this time Hole returns in low-pressure reservoir, and then the two-stage electromagnetic iron coil of pressurization control valve portion is powered, and two-stage electromagnetic iron attracts second level rank Iron, then second level armature drives supercharger control valve valve rod to be detached from level-one armature and continues up at second level limiting position of armature；Increase Pressure control valve valve rod is detached from the continuation of bacterium shape sleeve and up moves, and T-type way to cycle oil is opened, the intracavitary fuel oil of two-stage supercharging passes through The T-type way to cycle oil that two-stage supercharging oil circuit passes through again in bacterium shape sleeve is flow back into low-pressure reservoir, and charged piston moves downward, and three Closed check valve at the oil inlet of grade booster cavity；Then injector control valve partial current, electromagnet attract armature, and armature drives Injection Control valve rod moves upwards by conical surface seal and to open low pressure oil leak hole, and the fuel oil in control chamber passes through low pressure draining Hole is flowed back in low-pressure reservoir, and fluid power compensating piston moves downward, closure of check ring, and fluid power compensating piston passes through fluid power compensating piston Fuel-displaced road direction control chamber repairing, when the resultant force of control cavity pressure and needle valve spring is less than in oil holding slot fuel oil to the hydraulic coupling of needle-valve When, needle-valve is lifted up, spray orifice oil spout；When the power-off of Injection Control valve portion, injector control valve valve rod is in injector control valve valve It takes a seat under the elastic force effect of bar return spring, high-pressure oil passage is opened while by low pressure draining bore closure, check-valves is opened, control Chamber processed builds pressure by oil inlet metering-orifice and fluid power compensating piston cavity of resorption again, when the elastic force shape of pressure and needle valve spring in control chamber At resultant force be greater than the upward hydraulic coupling of fuel oil in oil holding slot when, needle-valve drops back into one's seat；When the power-off of pressurization control valve portion, increase Pressure control valve valve rod drives bacterium shape sleeve to take a seat together under the spring-force driven dual of supercharger control valve reset spring, first returns T-type Oily access transverse direction oil circuit is closed, and the conical surface seal of bacterium shape sleeve upper end is then opened while by low pressure draining bore closure, high Compression ignition oil reenters level-one booster cavity and two-stage supercharging chamber by level-one Pressure Increasing Oil-Line and two-stage supercharging oil circuit, charged piston to On return to initial position, check valve is again turned on, and fuel oil is entered in three-level booster cavity by check valve and enters back into oil holding slot.

4, at three rib type parts at supercharger control valve valve rod and bacterium shape sleeve cooperation, bacterium shape sleeve lining length is longer than trigone Type partial-length.

Present invention has an advantage that the pressure-accumulating type electronic control fuel injection device that 1, fuel injection characteristic of the invention can be changed uses three-level step The charged piston of circular table changes pressure ratio by way of changing pressure application surface product, makes the fuel pressure in oil holding slot It can be adjusted according to actual condition, effectively improve the flexibility of oil spout, diesel engine is enable to better meet sternly The emission regulation demands of lattice, the effective economy and dynamic property for improving diesel engine；2, the supercharger control valve energy that the present invention uses It is enough to realize multistage positioning, it realizes that the on-off of a plurality of Pressure Increasing Oil-Line is controllable, so as to adjust the high pressure oil active area of charged piston, protects Demonstrate,prove the flexible control of electric-controlled fuel injector pressure ratio；3, the low pressure oil leak hole in injector control valve valve rod is connected with electromagnetism valve chamber, Fuel oil in control chamber also plays the effect of cooling solenoid valve by the oil return of low pressure oil leak hole, can increase solenoid valve The stability of work, in addition the low pressure oil leak hole in control valve valve rod reduces the quality of injector control valve valve rod, makes oil spout control Response valve processed is accelerated；4, pressure accumulation chamber 18 can slowing oil injection when caused pressure oscillation, be conducive to the accurate of distributive value Control, is remarkably improved especially for the control precision of small oil mass.Requirement of the common rail pipe to material is advantageously reduced simultaneously, is mentioned Its high service life.It is provided with AND DEWATERING FOR ORIFICE STRUCTURE in pressure accumulation chamber 18, to from pressure accumulation chamber 18 flows to the fuel oil of fuel injector high-pressure oil pipe To the effect of throttling and filtering, to reduce the pressure oscillation of fuel injector intermediate fuel oil, circulating fuel injection quantity fluctuation is reduced, further more Accurately control high-pressure common-rail fuel system multi-injection process；5, fluid power compensating piston can be during control chamber oil return It can play the role of the repairing into control chamber, slow down control chamber oil pressure decrease speed, play bypass during control chamber builds pressure Control chamber voltage built-up rate is accelerated in the effect of oil circuit, so that rule anxious after first delaying is presented in fuel injection characteristic curve.

Detailed description of the invention

Fig. 1 is the structural diagram of the present invention；

Fig. 2 is fuel injector schematic diagram；

Fig. 3 is supercharger control valve partial schematic diagram；

Fig. 4 is three-level piston component schematic diagram；

Fig. 5 is injector control valve partial schematic diagram；

Fig. 6 is needle-valve portion schematic diagram；

Fig. 7 is fluid power compensating piston partial schematic diagram.

Specific embodiment

It illustrates with reference to the accompanying drawing and the present invention is described in more detail:

In conjunction with Fig. 1-7, the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic of the present invention, including common rail pipe 9, high pressure Oil pipe 7, high-pressure oil pump 1, filter 3, fuel tank 4, oil return pipe 2 and fuel injector 6 are constituted, 9 right end of common rail pipe respectively with high-pressure oil pump 1, filter 3 is connected to fuel tank 4, multiple hydraulic oil outlets 8 is provided on common rail pipe 9, the number of hydraulic oil outlet 8 is according to internal combustion engine gas The number of cylinder determines that hydraulic oil outlet 8 is connected by the fuel inlet 20 being provided on high-pressure oil pipe 7 and fuel injector, and oil spout The low pressure oil return opening 5 being provided on device is connected to fuel tank 4 by oil return pipe 2.Fuel injector 6 is controlled by fastening cap 10, pressure accumulation cavity wall 11, pressurization Valve portion 12, three-level piston component 13, Injection Control valve portion 14, needle-valve portion 15, oil injector body 17, pressure accumulation chamber 18 and filter processed Wave hole plate 19 forms.The pressurization control valve portion 12 is mainly by two-stage electromagnetic iron coil 21 and second level armature 22, level-one electricity Magnet coil 23 and level-one armature 24, charged piston limit orifice plate 28, bacterium shape sleeve 31, bacterium shape sleeve spring 30, dual-coil electromagnetic valve Limit 37 groups of orifice plate 34, supercharger control valve valve rod 36, level-one armature fixed spring 35 and supercharger control valve valve rod reset spring Be provided with T-type way to cycle oil 26 at, 36 head of supercharger control valve valve rod, 31 sets of bacterium shape sleeve on 36 head of supercharger control valve valve rod, The lateral oil circuit of T-type way to cycle oil 26, the longitudinal oil circuit of T-type way to cycle oil 26 and low pressure oil leak hole are cut off and opened by relative motion 29 are connected, and supercharger control valve valve chamber 32 is communicated with level-one Pressure Increasing Oil-Line 27, two-stage supercharging oil circuit 25 and pressurization throttle orifice 33, bacterium Shape sleeve 31 is located in supercharger control valve valve chamber 32.Three-level piston component 13 mainly includes charged piston 44, piston return spring 41 and check valve 43, charged piston 44 is three-level step frustum cone structure, and charged piston 44 and oil injector body 17 constitute level-one and increase Pressure chamber 38, two-stage supercharging chamber 39 and three-level booster cavity 40, level-one booster cavity 38 are connected with level-one Pressure Increasing Oil-Line 27, two-stage supercharging Chamber 39 is connected with two-stage supercharging oil circuit 25, and three-level booster cavity 40 is connected with oil holding slot 60, and passes through check valve 43 and high pressure Oil circuit is connected.Be machined with low pressure oil leak hole 48 in injector control valve valve rod 47, be connected with electromagnetism valve chamber, electromagnetism valve chamber with it is low Pressure oil case 4 is connected.Needle-valve portion 15 includes check-valves 63, fluid power compensating piston 64, fluid power compensating piston spring 68, control chamber 55, oil holding slot 60, spray orifice 59, needle-valve 57 and needle-valve reset spring 56.Fluid power compensating piston part 62 is mounted on needle-valve portion 15 Top, needle-valve limit orifice plate 61 in be equipped with fluid power compensating piston epicoele 70, fluid power compensating piston cavity of resorption 69 and fluid power compensation live Draining chamber 67 is filled in, 70 top of fluid power compensating piston epicoele is provided with to be connected to high-pressure oil passage, and fluid power compensating piston cavity of resorption 69 is distinguished It is connected to fluid power compensating piston in-line 65 and fluid power compensating piston vent line 66, is equipped in fluid power compensating piston in-line 65 Check-valves 63.

Fig. 1 is the pressure accumulation type electric control fuel oil jet system overall structure diagram that fuel injection characteristic of the present invention can be changed, including altogether Rail pipe 9, high-pressure oil pipe 7, high-pressure oil pump 1, filter 3, fuel tank 4, oil return pipe 2 and fuel injector 6.9 right end of common rail pipe passes through difference Be connected to high-pressure oil pump 1, filter 3 and fuel tank 4, be provided with multiple hydraulic oil outlets 8 on common rail pipe 9, hydraulic oil outlet 8 it is several Determine that hydraulic oil outlet 8 passes through 20 phase of fuel inlet being provided on high-pressure oil pipe 7 and fuel injector 6 according to the number of cylinder of internal-combustion engine Connection, and the low pressure oil return opening 5 being provided on fuel injector is connected to fuel tank 4 by oil return pipe 2.

Fig. 2 is the overall structure of fuel injector 6, mainly by fastening cap 10, pressure accumulation cavity wall 11, pressurization control valve portion 12, three Grade piston component 13, Injection Control valve portion 14, needle-valve portion 15, oil injector body 17 and filtering orifice plate 19 form.Fastening cap 10, which are linked closely pressurization control valve portion 12 by screw thread, is fixed on oil injector body 17, and pressure accumulation cavity wall 11 passes through screw thread for oil spout control Valve portion 14 processed, which is pressed together and linked closely with needle-valve portion 15, to be fixed on oil injector body 17, and fastening cap 10 will be stored by screw thread It presses chamber 18 to close, while being machined with fuel feed hole 23 on fastening cap 10 for high pressure oil to be introduced into pressure accumulation chamber 18.The tight cap 16 of nozzle Injection Control valve portion 14 and needle-valve portion 15 are pressed together and linked closely by screw thread and is fixed on oil injector body 17.

Fig. 3 is the pressurization control valve portion 12 of fuel injector 6, and pressurization control valve portion 12 mainly includes two-stage electromagnetic iron coil 21, two-stage electromagnetic valve 22, level-one electromagnet coil 23, level-one armature 24, charged piston limit orifice plate 28, bacterium shape sleeve 31, bacterium Shape sleeve spring 30, dual-coil electromagnetic valve limit orifice plate 34, supercharger control valve valve rod 36, level-one armature fixed spring 35 and pressurization control Valve valve rod reset spring 37 processed.Level-one electromagnet coil 23 is superimposed placement with two-stage electromagnetic iron coil 21, wherein two-stage electromagnetic iron Coil 21 is located at the top of level-one electromagnet coil 23.Dual-coil electromagnetic valve limits orifice plate 34 and charged piston limit orifice plate 28 forms and increases Pressure control valve valve chamber 32, dual-coil electromagnetic valve limit and are machined with pressurization throttle orifice 33 and two-stage supercharging oil circuit 25 on orifice plate 34, pressurization section One end of discharge orifice 33 and two-stage supercharging oil circuit 25 is all connected with supercharger control valve valve chamber 32, pressurization 33 other end of throttle orifice and height Pressure oil road is connected, and high pressure oil is introduced supercharger control valve valve chamber 32.Low pressure draining is machined on charged piston limit orifice plate 34 Hole 29 and level-one Pressure Increasing Oil-Line 27, low pressure oil leak hole 29 and level-one Pressure Increasing Oil-Line 27 are all connected with supercharger control valve valve chamber 32, Low pressure oil leak hole 29 is connected to low-pressure reservoir 4.Bacterium shape sleeve 31 is placed in supercharger control valve valve chamber 32, and bacterium shape sleeve 31 passes through For 30 pressing sleeve of bacterium shape sleeve spring on the head of supercharger control valve valve rod 36, supercharger control valve valve rod 36 can be in bacterium shape sleeve 31 It slides up and down.36 head of supercharger control valve valve rod is machined with T-type way to cycle oil 26, the vertical access of T-type way to cycle oil 26 and bacterium The access of shape sleeve 31 is connected, when bacterium shape sleeve 31 is pressed on supercharger control valve valve rod 36, the cross of T-type way to cycle oil 26 It is to close to access, when supercharger control valve valve rod 36 is moved up with respect to bacterium shape sleeve 31, T-type way to cycle oil 26 is opened. Supercharger control valve valve rod 36 and bacterium shape sleeve 31 are pressed on charged piston limit orifice plate by supercharger control valve valve rod reset spring 37 On 28, and low pressure oil leak hole 29 is closed.Supercharger control valve valve rod 36 passes through hole among level-one electromagnet coil 23 and double Solenoid valve limits orifice plate 34, is placed with level-one armature 24 between level-one electromagnet coil 23 and dual-coil electromagnetic valve limit orifice plate 34, Supercharger control valve valve rod 36 passes through 24 center of level-one armature, and level-one armature 24 is fixed on supercharger control valve by level-one armature spring 35 On valve rod 36, magneticaction of the level-one armature 24 by level-one electromagnet coil 23, when level-one armature 24 is attracted, pressurization control Valve valve rod 36 processed can be detached from level-one armature 24 and move upwards.Second level armature 22 is placed in 36 top of supercharger control valve valve rod, and It is connect with supercharger control valve valve rod 36, second level armature 22 can be by the electromagnetic force of two-stage electromagnetic iron coil 21.

Fig. 4 show the structural schematic diagram of the three-level piston component 13 of fuel injector 6, including charged piston 44, oil injector body 17, piston return spring 41 and check valve 43.Charged piston 44 is a three-level stepped cylinder structure, with charged piston limit hole Plate 28 collectively forms plunger shaft 45, and high pressure oil is passed through plunger shaft 45 by the hole opened on piston limit orifice plate 28.Charged piston 44 Level-one booster cavity 38, two-stage supercharging chamber 39 and three-level booster cavity 40 are collectively formed with oil injector body 17, wherein level-one booster cavity 38 It is connected respectively with level-one Pressure Increasing Oil-Line 27 and two-stage supercharging oil circuit 25 with two-stage supercharging chamber 39, in supercharger control valve valve chamber 32 High pressure oil respectively enters level-one booster cavity 36 and two-stage supercharging chamber 37 by level-one Pressure Increasing Oil-Line 27 and two-stage supercharging oil circuit 25.Three Grade booster cavity 40 is connected by check valve 43 with high-pressure oil passage, piston return spring 41 is placed in three-level booster cavity 40, together When 40 lower part of three-level booster cavity be also provided with Pressure Increasing Oil-Line 42, the oil in three-level booster cavity 40 is introduced into oil holding slot by Pressure Increasing Oil-Line 42 60。

Fig. 5 show the structural schematic diagram of the Injection Control valve portion 14 of fuel injector 6, including electromagnet 43, Injection Control Valve valve rod 47, armature 52, injector control valve valve rod return spring 54 and injector control valve limit orifice plate 53.Injector control valve limit Orifice plate 53 and intermediate orifice plate 50 collectively form injector control valve valve chamber 49, and 47 lower end of injector control valve valve rod is a bacterium shape knot Structure is located in injector control valve valve chamber 49.Low pressure oil leak hole 48, injector control valve valve are machined among injector control valve valve rod 47 Injector control valve valve rod 47 is pressed on intermediate orifice plate 50 by bar return spring 54, and low pressure oil leak hole 48 is closed.Injection Control It is provided with high-pressure oil passage in valve limit orifice plate 53 and is also provided with oil inlet quantity towards injector control valve valve chamber 49, while on needle-valve limit orifice plate Hole 51,51 one end of oil inlet metering-orifice are connected to injector control valve valve chamber 49, and the other end is connected to control chamber 55, and high pressure oil is introduced into In control chamber 55.

Fig. 6 show the structural schematic diagram of the needle-valve portion 15 of fuel injector 6, including needle-valve 57, needle valve spring 56, fluid power are mended Repay piston portion 62 and nozzle 58.Fluid power compensating piston part 62 is as shown in fig. 7, comprises fluid power compensating piston 64 and fluid power compensation Piston spring 68.Fluid power compensating piston part 62 is located in needle-valve limit orifice plate 61, forms fluid power with needle-valve limit orifice plate 61 and mends Piston cavity of resorption 69 and fluid power compensating piston draining chamber 67 are repaid, while forming fluid power compensating piston epicoele 70, needle with intermediate orifice plate 50 Valve spring 56 is located in fluid power compensating piston cavity of resorption 69.Fluid power compensating piston epicoele 70 is connected with high-pressure oil passage, and fluid power is mended Piston cavity of resorption 69 is repaid respectively by fluid power compensating piston in-line 65 and fluid power compensating piston vent line 66 and injector control valve valve Chamber 49 is connected with control chamber 55, is wherein provided with check-valves 63 in fluid power compensating piston in-line 65.Nozzle 58 and needle-valve limit Position orifice plate 61 constitutes control chamber 55 and oil holding slot 60, needle valve spring 56 are located in control chamber 55.58 lower end of nozzle is provided with spray orifice 59, When the resultant force of the pressure initiation in 56 elastic force of needle valve spring and control chamber 55 is greater than the pressure that oil holding slot 60 applies needle-valve 57, Needle-valve 57, which is taken a seat, closes spray orifice 59；When needle-valve 57 lifts, spray orifice 59 is connected to oil holding slot 60, commencement of fuel injection.

The draw fuel from fuel tank 4 of high-pressure oil pump 1 is provided with filter 3 between high-pressure oil pump 1 and fuel tank 4, and fuel oil passes through Filter 3 is filtered.Then fuel oil is transported to common rail pipe 9, and multiple hydraulic oil outlets 8, each hydraulic oil are provided on common rail pipe 9 Outlet 8 is all connected by high-pressure oil pipe 7 with fuel injector 6, and high pressure fuel is transported to the fuel inlet 20 of fuel injector.Fuel oil from Fuel inlet 20 enters pressure accumulation chamber 18, and filtering orifice plate is horizontally arranged in pressure accumulation chamber 18, and pressure accumulation chamber 18 is located at fuel injector 6 The top is connected with fuel inlet and lower section high-pressure oil passage respectively, and high-pressure oil passage draws one at dual-coil electromagnetic valve limit orifice plate 34 Branch is entered in supercharger control valve valve chamber 32 by being pressurized throttle orifice 33, is divided into two using supercharger control valve valve chamber 32 Road, enters level-one booster cavity 38 by level-one Pressure Increasing Oil-Line 27 all the way, and another way enters second level by two-stage supercharging oil circuit 25 Booster cavity 39.Fuel oil continues to draw a branch at charged piston limit orifice plate 28 down, this branch leads to plunger shaft 45. Fuel oil is divided into two-way in the continuation of oil injector body 17 down and wherein: continuing to limit orifice plate 53 by injector control valve down all the way In high-pressure oil passage enter injector control valve valve chamber 49, then control chamber 55 is entered by oil inlet metering-orifice 51；Another way passes through list It enters in three-level booster cavity 40 to valve 43, is entered in oil holding slot 60 by Pressure Increasing Oil-Line 42 still further below.Plunger shaft 45 at this time Interior hydraulic coupling is less than level-one booster cavity 38, two-stage supercharging chamber 39 and hydraulic coupling and piston return bullet in three-level booster cavity 40 The resultant force that the elastic force of spring 41 is formed, charged piston 44 is in extreme higher position, therefore the fuel oil in three-level booster cavity 40 is not pressurized. The resultant force that the pressure in oil holding slot 60 and needle valve spring 56 are formed simultaneously is greater than the pressure in control chamber 55, and needle-valve 57 is fallen at this time Seat.According to the difference of injection process, fuel injector 6 can be divided into three kinds of different operating modes: without boost mode, low pressure charging mode and High pressure-charging mode.

When fuel injector 6 works under no boost mode, 12 no power of pressurization control valve portion, due to three-level piston at this time The pressure balance of each acting surface, check valve 43 is opened, therefore the fuel pressure in three-level booster cavity 40 does not increase, oil holding slot Fuel pressure in 60 is equal to the pressure of check valve another side.When Injection Control valve portion 14 is powered, electromagnet 46 attracts rank Iron 52, armature 52 drive injector control valve valve rod 47 to move upwards by conical surface seal and to open low pressure oil leak hole 48, control Fuel oil in chamber 55 enters electromagnetism valve chamber by the low pressure oil leak hole 48 in injector control valve valve rod 47, using setting in electricity Low pressure oil way in magnet valve chamber returns in low-pressure reservoir 4, thus the pressure reduction in control chamber 55, while fluid power compensating piston The pressure of fluid power compensating piston cavity of resorption 69 decreases in part 62, and the pressure of fluid power compensating piston epicoele 70 is compensated greater than fluid power The resultant force that the elastic force of 69 pressure of piston cavity of resorption and fluid power compensating piston spring 67 is formed, fluid power compensating piston 64 is transported downwards at this time Dynamic, check-valves 63 is closed, and fluid power compensating piston 64, to 55 repairing of control chamber, makes control chamber by fluid power compensating piston vent line 66 55 pressure decrease speeds slow down.When the resultant force that the elastic force of pressure and needle valve spring 56 in control chamber 55 is formed is less than oil holding slot 60 When the upward hydraulic coupling of interior fuel oil, needle-valve 57 is lifted up, and spray orifice 59 is opened, 6 commencement of fuel injection of fuel injector.When Injection Control valve portion When points 14 power-off, injector control valve valve rod 47 is taken a seat under the elastic force effect of injector control valve valve rod return spring 54, will be low Pressure oil leak hole 48 opens high-pressure oil passage while closing, check-valves 63 is opened, and control chamber 55 is mended by oil inlet metering-orifice 51 and fluid power It repays piston cavity of resorption 69 and builds pressure again, when the resultant force that the elastic force of pressure and needle valve spring 56 in control chamber 55 is formed is greater than oil holding slot In 60 when the upward hydraulic coupling of fuel oil, needle-valve 57 drops back into one's seat, and fuel injector 6 stops oil spout.

When fuel injector 6 works under low pressure charging mode, the level-one electromagnet coil 23 of pressurization control valve portion 12 is powered, Level-one electromagnet attracts level-one armature 24, and level-one armature 24 drives supercharger control valve valve rod 36 to move upward to level-one electromagnet limit At position.Bacterium shape sleeve 31, as supercharger control valve valve rod 36 is lifted up, is incited somebody to action under the action of bacterium shape 30 spring force of sleeve spring Low pressure oil leak hole 29 is opened, until by the conical surface seal of the top of bacterium shape sleeve 31.Fuel oil in level-one booster cavity 38 passes through level-one Pressure Increasing Oil-Line 27 flows through low pressure oil leak hole 29 and returns in low-pressure reservoir 4, at this time the pressure reduction in level-one booster cavity 38, plunger shaft Pressure in 45 is greater than level-one booster cavity 38, two-stage supercharging chamber 39 and pressure and piston return spring 41 in three-level booster cavity 40 The sum of elastic force, charged piston 44 moves downward, and the check valve 43 at the oil inlet of three-level booster cavity 40 is closed, three-level booster cavity Fuel pressure in 40, which is pressurized, to be increased, and then the fuel pressure in oil holding slot 60 is caused to increase.Subsequent 3 part of injector control valve is logical Electricity, electromagnet 46 attract armature 52, and armature 52 drives injector control valve valve rod 47 to move upwards by conical surface seal and to open Low pressure oil leak hole 48, the fuel oil in control chamber 55 are flowed back in low-pressure reservoir 4 by low pressure oil leak hole 48.At this time in control chamber 55 Pressure reduction, while the pressure of fluid power compensating piston cavity of resorption 69 decreases in fluid power compensating piston part 62, fluid power compensation is lived The pressure of chamber 70 is greater than the resultant force of the elastic force formation of 69 pressure of fluid power compensating piston cavity of resorption and fluid power compensating piston spring 67 beyond the Great Wall, Fluid power compensating piston 64 moves downward at this time, and check-valves 63 is closed, and fluid power compensating piston 64 passes through fluid power compensating piston vent line 66, to 55 repairing of control chamber, slow down 55 pressure decrease speed of control chamber.It is contained when its pressure and the resultant force of needle valve spring 56 are less than When fuel oil is to the hydraulic coupling of needle-valve 57 in oil groove 60, needle-valve 57 is lifted up, and spray orifice 59 is opened, 6 commencement of fuel injection of fuel injector.Work as spray When oil control valve part 14 powers off, injector control valve valve rod 47 is acted in the elastic force of injector control valve valve rod return spring 54 and being fallen Seat opens high-pressure oil passage while closing low pressure oil leak hole 48, and check-valves is opened, and control chamber 55 passes through 51 He of oil inlet metering-orifice Fluid power compensating piston cavity of resorption 69 builds pressure again, when the resultant force that the elastic force of pressure and needle valve spring 56 in control chamber 55 is formed is greater than In oil holding slot 60 when the upward hydraulic coupling of fuel oil, needle-valve 57 drops back into one's seat, and fuel injector 6 stops oil spout.When pressurization control valve portion When 12 power-off, supercharger control valve valve rod 36 drives bacterium shape sleeve 31 1 under the spring-force driven dual of supercharger control valve reset spring 37 It rises and takes a seat, the conical surface seal of 31 upper end of bacterium shape sleeve is opened while closing low pressure oil leak hole 29, high pressure fuel passes through one Grade Pressure Increasing Oil-Line 27 reenters level-one booster cavity 38, and the pressure in plunger shaft 45 is less than level-one booster cavity 38 at this time, second level increases The sum of the elastic force of the pressure and piston return spring 41 in chamber 39 and three-level booster cavity 40 is pressed, charged piston 44 is back up into initial Position.Pressure reduction in three-level booster cavity 40, check valve 43 are again turned on, and fuel oil enters three-level pressurization by check valve 43 Oil holding slot 60 is entered back into chamber 41.

When fuel injector 6 works under high pressure-charging mode, the level-one electromagnet coil 23 of pressurization control valve portion 12 first It is powered, level-one electromagnet attracts level-one armature 24, and level-one armature 24 drives supercharger control valve valve rod 36 to move upward to level-one electricity Magnet spacing place.Bacterium shape sleeve 31 is under the action of bacterium shape 30 spring force of sleeve spring as supercharger control valve valve rod 36 is lifted upwards It rises, opens low pressure oil leak hole 29 while by the conical surface seal of the top of bacterium shape sleeve 31.At this time in level-one booster cavity 38 Fuel oil flows through low pressure oil leak hole 29 by level-one Pressure Increasing Oil-Line 27 and returns in low-pressure reservoir 4,38 pressure reduction of level-one booster cavity.So The two-stage electromagnetic iron coil 21 of pressurization control valve portion 12 is powered afterwards, and two-stage electromagnetic iron attracts second level armature 22, and then second level is held in the mouth Iron 22 drives supercharger control valve valve rod 36 to be detached from level-one armature 24 and continues up at second level limiting position of armature.Pressurization control at this time Valve valve rod 36 processed is detached from the continuation of bacterium shape sleeve 31 and up moves, and T-type way to cycle oil 26 is opened, the fuel oil in two-stage supercharging chamber 39 It is flow back into low-pressure reservoir 4 by the T-type way to cycle oil 26 in bacterium shape sleeve 31 again by two-stage supercharging oil circuit 25, two-stage supercharging 39 pressure of chamber also declines.The pressure in plunger shaft 45 is greater than level-one booster cavity 38, two-stage supercharging chamber 39 and three-level and increases at this time The resultant force for pressing the elastic force of pressure and charged piston return spring 41 in chamber 40 to be formed, charged piston 44 move downward, and three-level increases The check valve 43 at the oil inlet of chamber 40 is pressed to close, the fuel pressure in three-level booster cavity 40 increases, and then leads to oil holding slot 60 Interior fuel pressure increases.Then Injection Control valve portion 14 is powered, and electromagnet 46 attracts armature 52, and armature 52 drives oil spout control Valve rod 47 processed moves upwards by conical surface seal and to open low pressure oil leak hole 48, and the fuel oil in control chamber 55 passes through low pressure draining Hole 48 is flowed back in low-pressure reservoir 4.Pressure reduction in control chamber 55 at this time, while fluid power compensates in fluid power compensating piston part 62 The pressure of piston cavity of resorption 69 decreases, the pressure of fluid power compensating piston epicoele 70 be greater than 69 pressure of fluid power compensating piston cavity of resorption with The resultant force that the elastic force of fluid power compensating piston spring 67 is formed, fluid power compensating piston 64 moves downward at this time, and check-valves 63 is closed, liquid Force compensating piston 64, to 55 repairing of control chamber, subtracts 55 pressure decrease speed of control chamber by fluid power compensating piston vent line 66 It is slow.When the resultant force of its pressure and needle valve spring 56 is less than the hydraulic coupling of fuel oil in oil holding slot 60 to 57 valve of needle, needle-valve 57 is upward It lifts, spray orifice 59 is opened, 6 commencement of fuel injection of fuel injector.When Injection Control valve portion 14 powers off, injector control valve valve rod 47 is spraying It takes a seat under the elastic force effect of oil control valve valve rod return spring 54, opens high pressure oil while closing low pressure oil leak hole 48 Road, check-valves 63 are opened, and control chamber 55 builds the newly-built pressure of ballast by oil inlet metering-orifice 51 and fluid power compensating piston cavity of resorption 69 again, when When the resultant force that the elastic force of pressure and needle valve spring 56 in control chamber 55 is formed is greater than the upward hydraulic coupling of fuel oil in oil holding slot 60, Needle-valve 57 drops back into one's seat, and fuel injector 6 stops oil spout.When pressurization control valve portion 12 powers off, supercharger control valve valve rod 36 is increasing Bacterium shape sleeve 30 is driven to take a seat together under the spring-force driven dual of pressure control valve reset spring 37, laterally by T-type way to cycle oil 26 first Oil circuit is closed, and the conical surface seal of 31 upper end of bacterium shape sleeve, high pressure fuel are then opened while closing low pressure oil leak hole 29 Level-one booster cavity 38 and two-stage supercharging chamber 39 are reentered by level-one Pressure Increasing Oil-Line 27 and two-stage supercharging oil circuit 25, at this time piston Pressure in chamber 45 is less than level-one booster cavity 38, two-stage supercharging chamber 39 and pressure and charged piston return in three-level booster cavity 40 The sum of the elastic force of spring 41, charged piston 44 is back up into initial position.Pressure reduction in three-level booster cavity 40, check valve 43 It is again turned on, fuel oil enters in three-level booster cavity 40 by check valve 43 and enters back into oil holding slot 60.

By the course of work of fuel injector it is found that the present invention passes through the movement sound for changing supercharger control valve during the work time It answers, it can be achieved that different pressure ratios makes fuel injector can be realized more flexible injection characteristics to reach different injection pressures. Present invention employs the injector control valves of electromagnetic type simultaneously, and which further improves the response speed of fuel injector and control essences Degree, make multi-injection working method is implemented as possibility.Effectively increase the dynamic property of diesel engine and the economy of fuel oil.? Way to cycle oil is set in injector control valve valve rod, oil return circuit is arranged in injector control valve, cooling solenoid valve is played Effect improves the reliability of the present invention at work.Pressure accumulation chamber can effectively extenuate caused pressure oscillation when fuel oil injection, Be conducive to the accurate control to distributive value, the pressure stabilization function of pressure accumulation chamber can be such that the size of common rail for diesel engine pipe reduces, this is advantageous In reducing requirement of the common rail pipe to material, its service life is improved.Meanwhile it being provided with AND DEWATERING FOR ORIFICE STRUCTURE in pressure accumulation chamber, on orifice plate It is drilled with the throttle orifice of different pore size, plays the role of throttling and filtering to the fuel oil for flowing to fuel injector high-pressure oil pipe from pressure accumulation chamber, To reduce the pressure oscillation of fuel injector intermediate fuel oil, circulating fuel injection quantity fluctuation is reduced, further more accurate control high-pressure common rail Fuel system multi-injection process.The repairing in control chamber pressure release of the fluid power compensating piston structure of use, plays two-way when building pressure The effect of oil inlet improves oil spout performance so that fuel injection characteristic realizes characteristic anxious after first delaying.

Claims

1. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic, it is characterized in that: including fuel injector, common rail pipe, high pressure oil Pipe, fuel tank, high-pressure oil pump, oil return pipe；

The fuel injector includes oil injector body, pressure accumulation cavity wall, pressurization control valve portion, three-level piston component, Injection Control valve portion Point, needle-valve portion, pressurization control valve portion and three-level piston be mounted in oil injector body from top to bottom, Injection Control valve portion and Needle-valve portion is arranged in from top to bottom in the tight cap of nozzle, and tight cap of spraying nozzle is fixed below oil injector body, and pressure accumulation cavity wall is fixed on increasing Pressure control valve upper, pressure accumulation chamber and high-pressure oil passage are arranged in pressure accumulation cavity wall, and pressure accumulation chamber is connected to high-pressure oil passage；

The pressurization control valve portion includes supercharger control valve upper valve base, supercharger control valve centre valve seat, dual-coil electromagnetic valve limit hole Plate, charged piston limit orifice plate, supercharger control valve valve rod, level-one armature, second level armature, bacterium shape sleeve, supercharger control valve upper valve Valve seat, dual-coil electromagnetic valve limit orifice plate and charged piston limit orifice plate are arranged from top to bottom among seat, supercharger control valve, pressurization control The head of valve valve rod is located to be limited in the supercharger control valve valve chamber that orifice plate and charged piston limit orifice plate are constituted by dual-coil electromagnetic valve, Outside is bacterium shape sleeve, and second level armature is installed in the tail portion of supercharger control valve valve rod, and level-one is installed at the middle part of supercharger control valve valve rod Armature, second level armature are located among supercharger control valve in valve seat, and level-one armature is located in dual-coil electromagnetic valve limit orifice plate, pressurization control Two-stage electromagnetic iron coil is wound in valve upper valve base, winds level-one electromagnet coil, pressurization control among supercharger control valve in valve seat Supercharger control valve valve rod reset spring, supercharger control valve are set between valve valve rod tail portion and supercharger control valve upper valve base above it The part that valve rod is located at below level-one armature is cased with level-one armature fixed spring, the extension of bacterium shape sleeve and the pressurization of lower section Bacterium shape sleeve spring is set between piston limit orifice plate, and the head of supercharger control valve valve rod is machined with T-type way to cycle oil, and T-type returns Oily access includes the vertical access communicated and cross walkway, and dual-coil electromagnetic valve limits setting pressurization throttle orifice, two-stage supercharging on orifice plate Oil circuit, charged piston, which limits, is arranged level-one Pressure Increasing Oil-Line and low pressure oil leak hole on orifice plate, pressurization throttle orifice, two-stage supercharging oil circuit, Level-one Pressure Increasing Oil-Line is connected to supercharger control valve valve chamber with low pressure oil leak hole, is pressurized the other end connection high-pressure oil passage of throttle orifice, Low pressure oil leak hole is connected to fuel tank；

The three-level piston component includes charged piston, piston return spring, and charged piston is three-level stepped cylinder structure, from upper And lower is respectively the first-third cylinder, and diameter successively decreases, the first cylinder and the charged piston above it are limited and are formed between orifice plate Plunger shaft, plunger shaft limit the hole in orifice plate by charged piston and are connected to high-pressure oil passage, the first cylinder and the second cylinder and oil spout Level-one booster cavity is formed between body, and two-stage supercharging chamber, third column are formed between the second cylinder and third cylinder and oil injector body Three-level booster cavity is formed between body and oil injector body below, and piston return spring, level-one pressurization are installed in three-level booster cavity Chamber is connected to level-one Pressure Increasing Oil-Line, and two-stage supercharging chamber is connected to two-stage supercharging oil circuit, and three-level booster cavity is connected to high pressure oil by check valve Road, three-level booster cavity lower part are provided with Pressure Increasing Oil-Line；

The Injection Control valve portion includes injector control valve upper valve base, injector control valve limit orifice plate, intermediate orifice plate, oil spout control Valve valve rod processed, armature, injector control valve upper valve base, injector control valve limit orifice plate and intermediate orifice plate are arranged from top to bottom, oil spout The setting of control valve valve rod limits in orifice plate in injector control valve, and armature is installed on the top of injector control valve valve rod, armature with thereon Injector control valve valve rod return spring is installed, outside injector control valve valve rod return spring between the injector control valve upper valve base of side Injector control valve upper valve base in wind electromagnet coil, low pressure oil leak hole, injector control valve are set in injector control valve valve rod It limits orifice plate and intermediate orifice plate constitutes injector control valve valve chamber, injector control valve stem lower portion includes tapered protrusion, Injection Control Valve, which limits, is arranged injector control valve in-line on orifice plate, injector control valve in-line is connected to high-pressure oil passage, is arranged on intermediate orifice plate Oil inlet metering-orifice, oil inlet metering-orifice are connected to injector control valve valve chamber；

The needle-valve portion includes needle-valve limit orifice plate, nozzle, and interstitial hole is arranged in needle-valve limit orifice plate and nozzle from top to bottom Below plate, fluid power compensating piston epicoele in-line, non-return passage are set in intermediate orifice plate, check-valves, liquid are installed in non-return passage Force compensating piston upper chamber in-line is connected to high-pressure oil passage, and non-return passage is connected to oil inlet metering-orifice, fluid power is arranged in needle-valve limit orifice plate Compensating piston, control chamber oil circuit, fluid power compensating piston reset spring is cased with outside fluid power compensating piston, and fluid power compensating piston resets The upper end of spring is withstood on fluid power compensating piston, and the lower end of fluid power compensating piston reset spring withstands on needle-valve limit hole below On plate, the fluid power compensating piston epicoele communicated with fluid power compensating piston epicoele in-line, fluid power are formed above fluid power compensating piston Compensating piston reset spring present position is fluid power compensating piston cavity of resorption, and fluid power compensating piston lower end is limited with needle-valve below Fluid power compensating piston draining chamber, control chamber oil communication oil inlet metering-orifice are formed between orifice plate；Needle-valve, needle-valve top are installed in nozzle It is cased with needle-valve reset spring, the upper end of needle-valve reset spring is withstood on needle-valve limit orifice plate, and the lower end of needle-valve reset spring is withstood on On needle-valve, needle-valve reset spring present position is control chamber, and control chamber is connected to control chamber oil circuit, oil holding slot oil inlet is arranged in nozzle Road forms oil holding slot between needle-valve and nozzle, spray orifice is arranged in nozzle bottom, and oil holding slot in-line is respectively communicated with oil holding slot and pressurization Oil circuit, fluid power compensating piston cavity of resorption are connected to the non-return passage below check-valves, fluid power compensation by fluid power compensating piston in-line Piston cavity of resorption is connected to control chamber by fluid power compensating piston vent line；

Fuel inlet above the pressure accumulation cavity wall of fuel injector is connected to the hydraulic oil outlet of common rail pipe by high-pressure oil pipe, and fuel tank passes through The hydraulic oil inlet of filter, high-pressure oil pump connection common rail pipe, the low pressure oil return opening of fuel injector are connected to fuel tank, the quantity of fuel injector with The number of cylinders of diesel engine is consistent.

2. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 1, it is characterized in that: the spray Oily device, under no boost mode, pressurization control valve portion no power, check valve is opened；When injector control valve partial current, electromagnetism Iron attracts armature, and armature drives injector control valve valve rod to move upwards by conical surface seal and to open low pressure oil leak hole, controls Intracavitary fuel oil enters electromagnetism valve chamber by the low pressure oil leak hole in injector control valve valve rod, using setting in electromagnetism valve chamber In low pressure oil way back in low-pressure reservoir, fluid power compensating piston moves downward, closure of check ring, and fluid power compensating piston passes through The fuel-displaced road direction control chamber repairing of fluid power compensating piston, when the resultant force that the elastic force of pressure and needle valve spring in control chamber is formed is less than In oil holding slot when the upward hydraulic coupling of fuel oil, needle-valve is lifted up, and spray orifice is opened；When the power-off of Injection Control valve portion, oil spout Control valve valve rod is taken a seat under the elastic force effect of injector control valve valve rod return spring, is beaten while by low pressure draining bore closure High-pressure oil passage is opened, check-valves is opened, and control chamber builds pressure by oil inlet metering-orifice and fluid power compensating piston cavity of resorption again, when in control chamber Pressure and the resultant force that is formed of elastic force of needle valve spring when being greater than the upward hydraulic coupling of fuel oil in oil holding slot, needle-valve drops back into one's seat.

3. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 1 or 2, it is characterized in that: institute State fuel injector, under low pressure charging mode, the level-one electromagnet coil power of pressurization control valve portion, level-one electromagnet attracts level-one rank Iron, level-one armature drive supercharger control valve valve rod to move upward to level-one electromagnet spacing place；Bacterium shape sleeve is in bacterium shape sleeve bullet As supercharger control valve valve rod is lifted up under the action of spring force, low pressure oil leak hole is opened, above by bacterium shape sleeve Conical surface seal.Fuel oil in level-one booster cavity flows through low pressure oil leak hole by level-one Pressure Increasing Oil-Line and returns in low-pressure reservoir, pressurization Piston moves downward, the closed check valve at the oil inlet of three-level booster cavity；Subsequent injector control valve partial current, electromagnet are inhaled Draw armature, armature drives injector control valve valve rod to move upwards to by conical surface seal and open low pressure oil leak hole, in control chamber Fuel oil flowed back in low-pressure reservoir by low pressure oil leak hole, fluid power compensating piston moves downward, closure of check ring, fluid power compensation live Plug is by the fuel-displaced road direction control chamber repairing of fluid power compensating piston, when the resultant force of control cavity pressure and needle valve spring is less than in oil holding slot When fuel oil is to the hydraulic coupling of needle-valve, needle-valve is lifted up, and spray orifice is opened；When the power-off of Injection Control valve portion, injector control valve Valve rod is taken a seat under the elastic force effect of injector control valve valve rod return spring, opens high pressure while by low pressure draining bore closure Oil circuit, check-valves are opened, and control chamber builds pressure by oil inlet metering-orifice and fluid power compensating piston cavity of resorption again, when the pressure in control chamber When being greater than the upward hydraulic coupling of fuel oil in oil holding slot with the resultant force that the elastic force of needle valve spring is formed, needle-valve drops back into one's seat；Work as pressurization When controlling valve portion power-off, supercharger control valve valve rod drives bacterium shape sleeve under the spring-force driven dual of supercharger control valve reset spring It takes a seat together, the conical surface seal of bacterium shape sleeve upper end is opened while by low pressure draining bore closure, high pressure fuel passes through level-one Pressure Increasing Oil-Line reenters level-one booster cavity, and charged piston is again turned on back up into initial position, check valve, and fuel oil passes through list It is entered in three-level booster cavity to valve and enters back into oil holding slot.

4. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 1 or 2, it is characterized in that: institute State fuel injector, under high pressure-charging mode, the level-one electromagnet coil power of pressurization control valve portion, level-one electromagnet attract one first Grade armature, level-one armature drive supercharger control valve valve rod to move upward to level-one electromagnet spacing place；Bacterium shape sleeve is in bacterium shape set It is lifted up under the action of cylinder spring force with supercharger control valve valve rod, while by conical surface seal above bacterium shape sleeve Open low pressure oil leak hole；The fuel oil in level-one booster cavity flows through low pressure oil leak hole by level-one Pressure Increasing Oil-Line and returns to low pressure oil at this time In case, then the two-stage electromagnetic iron coil of pressurization control valve portion is powered, and two-stage electromagnetic iron attracts second level armature, and then second level is held in the mouth Iron drives supercharger control valve valve rod to be detached from level-one armature and continues up at second level limiting position of armature；Supercharger control valve valve rod is de- It is up moved from the continuation of bacterium shape sleeve, T-type way to cycle oil is opened, the intracavitary fuel oil of two-stage supercharging passes through two-stage supercharging oil circuit again It is flow back into low-pressure reservoir by the T-type way to cycle oil in bacterium shape sleeve, charged piston moves downward, the oil inlet of three-level booster cavity Closed check valve at mouthful；Then injector control valve partial current, electromagnet attract armature, armature drive Injection Control valve rod to To by conical surface seal and open low pressure oil leak hole, the fuel oil in control chamber flows back to low-pressure reservoir by low pressure oil leak hole for upper movement Interior, fluid power compensating piston moves downward, closure of check ring, and fluid power compensating piston passes through the fuel-displaced road direction control chamber of fluid power compensating piston Repairing, when the resultant force for controlling cavity pressure and needle valve spring is less than the hydraulic coupling of fuel oil in oil holding slot to needle-valve, needle-valve is lifted upwards It rises, spray orifice oil spout；When the power-off of Injection Control valve portion, bullet of the injector control valve valve rod in injector control valve valve rod return spring It takes a seat under power effect, high-pressure oil passage is opened while by low pressure draining bore closure, check-valves is opened, and control chamber passes through oil inlet quantity Hole and fluid power compensating piston cavity of resorption build pressure again, contain when the resultant force that the elastic force of pressure and needle valve spring in control chamber is formed is greater than In oil groove when the upward hydraulic coupling of fuel oil, needle-valve drops back into one's seat；When the power-off of pressurization control valve portion, supercharger control valve valve rod exists Bacterium shape sleeve is driven to take a seat together under the spring-force driven dual of supercharger control valve reset spring, first by T-type way to cycle oil transverse direction oil circuit It closes, the conical surface seal of bacterium shape sleeve upper end is then opened while by low pressure draining bore closure, high pressure fuel passes through level-one Pressure Increasing Oil-Line and two-stage supercharging oil circuit reenter level-one booster cavity and two-stage supercharging chamber, and charged piston is back up into initial bit It sets, check valve is again turned on, and fuel oil is entered in three-level booster cavity by check valve and enters back into oil holding slot.

5. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 3, it is characterized in that: the spray Oily device, under high pressure-charging mode, the level-one electromagnet coil power of pressurization control valve portion, level-one electromagnet attract level-one rank first Iron, level-one armature drive supercharger control valve valve rod to move upward to level-one electromagnet spacing place；Bacterium shape sleeve is in bacterium shape sleeve bullet As supercharger control valve valve rod is lifted up under the action of spring force, opened while by conical surface seal above bacterium shape sleeve Low pressure oil leak hole；The fuel oil in level-one booster cavity flows through low pressure oil leak hole by level-one Pressure Increasing Oil-Line and returns to low-pressure reservoir at this time Interior, then the two-stage electromagnetic iron coil of pressurization control valve portion is powered, and two-stage electromagnetic iron attracts second level armature, then second level armature It drives supercharger control valve valve rod to be detached from level-one armature to continue up at second level limiting position of armature；Supercharger control valve valve rod is detached from The continuation of bacterium shape sleeve up moves, and T-type way to cycle oil is opened, and the intracavitary fuel oil of two-stage supercharging is led to again by two-stage supercharging oil circuit The T-type way to cycle oil crossed in bacterium shape sleeve is flow back into low-pressure reservoir, and charged piston moves downward, the oil inlet of three-level booster cavity The closed check valve at place；Then injector control valve partial current, electromagnet attract armature, and armature drives Injection Control valve rod upward To by conical surface seal and open low pressure oil leak hole, the fuel oil in control chamber flows back to low-pressure reservoir by low pressure oil leak hole for movement Interior, fluid power compensating piston moves downward, closure of check ring, and fluid power compensating piston passes through the fuel-displaced road direction control chamber of fluid power compensating piston Repairing, when the resultant force for controlling cavity pressure and needle valve spring is less than the hydraulic coupling of fuel oil in oil holding slot to needle-valve, needle-valve is lifted upwards It rises, spray orifice oil spout；When the power-off of Injection Control valve portion, bullet of the injector control valve valve rod in injector control valve valve rod return spring It takes a seat under power effect, high-pressure oil passage is opened while by low pressure draining bore closure, check-valves is opened, and control chamber passes through oil inlet quantity Hole and fluid power compensating piston cavity of resorption build pressure again, contain when the resultant force that the elastic force of pressure and needle valve spring in control chamber is formed is greater than In oil groove when the upward hydraulic coupling of fuel oil, needle-valve drops back into one's seat；When the power-off of pressurization control valve portion, supercharger control valve valve rod exists Bacterium shape sleeve is driven to take a seat together under the spring-force driven dual of supercharger control valve reset spring, first by T-type way to cycle oil transverse direction oil circuit It closes, the conical surface seal of bacterium shape sleeve upper end is then opened while by low pressure draining bore closure, high pressure fuel passes through level-one Pressure Increasing Oil-Line and two-stage supercharging oil circuit reenter level-one booster cavity and two-stage supercharging chamber, and charged piston is back up into initial bit It sets, check valve is again turned on, and fuel oil is entered in three-level booster cavity by check valve and enters back into oil holding slot.

6. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 1 or 2, it is characterized in that: increasing At three rib type parts at pressure control valve valve rod and the sleeve cooperation of bacterium shape, bacterium shape sleeve lining length is longer than three rib type partial-lengths.

7. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 3, it is characterized in that: pressurization control At three rib type parts at valve valve rod processed and the sleeve cooperation of bacterium shape, bacterium shape sleeve lining length is longer than three rib type partial-lengths.

8. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 4, it is characterized in that: pressurization control At three rib type parts at valve valve rod processed and the sleeve cooperation of bacterium shape, bacterium shape sleeve lining length is longer than three rib type partial-lengths.

9. the variable pressure accumulation type electric control fuel oil jet system of fuel injection characteristic according to claim 5, it is characterized in that: pressurization control At three rib type parts at valve valve rod processed and the sleeve cooperation of bacterium shape, bacterium shape sleeve lining length is longer than three rib type partial-lengths.