CN206722944U - A kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback - Google Patents

Abstract

The purpose of this utility model is to provide a kind of pressure accumulation orifice-plate type electric-controlled fuel injector with hydraulic feedback, including injector head, oil injector body, current limliting valve module, electromagnetic valve component, needle valve assembly, etc. part.Pressure accumulation chamber is provided with oil injector body, is connected with main fuel feed hole with current limliting valve module, when ensureing big pulsewidth oil spout, the stabilization of each cylinder injection process.Current limliting valve module is arranged on below pressure accumulation chamber, avoids the abnormal progress for continuing oil spout.The addition of electromagnetic valve component internal feedback oil circuit, slow down the unlatching of needle-valve, accelerate taking a seat for needle-valve.And the two-way oil-feed in the orifice throttle hole, annular side oil circuit in needle valve assembly, further speed up building for control chamber and pressed through journey, the response speed that needle-valve is taken a seat greatly improved.The AND DEWATERING FOR ORIFICE STRUCTURE of processing, effectively reduces the dynamic recirculating oil quantity in injection process in needle valve assembly, the characteristics of realizing On Fluctuations oil return.Nozzle segment internal hydraulic pressure balances, is poor without static pressure, realizes function of the fuel injector without static leakage.

Description

A kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback

Technical field

The utility model relates to a kind of engine fueling injection equipment, specifically high-pressure common rail oil injection device.

Background technology

Start progressively to use high speed electromagnetic valve type fuel injector in the market to adapt to newest Abgasgesetz.It is this automatically controlled The characteristics of fuel injector protrudes is the electric signal control high-speed electromagnetic valve using ECU output, to realize flexible oil spout rule Rule.It is high using the fuel injector of high-speed electromagnetic valve, its faster system response, control accuracy, there is the ability of multi-injection.But this electricity Controlling fuel injector, there is also area for improvement：In injection process, high pressure fuel always be present and flow through into and out of oily throttle orifice. This partial high pressure fuel oil is pressurizeed by oil pump, is but returned directly to fuel tank without acting, dynamic recirculating oil quantity is big, causes energy to damage Lose.Meanwhile in order to reduce the discharge of nitrogen oxides, it is desirable to the instantaneous injection rate of injection process is controlled, reduces injection The injection rate at initial stage.At the end of course of injection, fuel injector must rapid oil-break, i.e. needle-valve response of taking a seat is fast, to reduce The forming amount of grain thing.Therefore requirement of the diesel emission to fuel injector is that its injection process can form unlatching at initial stage slowly and terminate to close Close fast Fuel Injection Rate Shaping.

In addition, the accurate control of multi-injection fuel injection characteristic is the sharpest edges of diesel engine high-pressure co-rail electronic control injection system And key technology.In high pressure co-rail system multi-injection, surge pressure fluctuation caused by injection directly influences multi-injection reason Think the realization of fuel injection characteristic, and then influence the performance of diesel engine.

The content of the invention

The purpose of this utility model is to provide in multi-injection, can guarantee that fuel pressure fluctuation is small, while can realize On Fluctuations oil return, needle-valve quick response and a kind of resonance orifice-plate type electronic control injection with hydraulic feedback without static leakage function Device.

What the purpose of this utility model was realized in：

A kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback of the utility model, it is characterized in that：Including injector head, Oil injector body, current limliting valve module, electromagnetic valve component, needle valve assembly, descending high-pressure oil passage, injector head are arranged on oil injector body Side, injector head inside set main fuel feed hole, set pressure accumulation chamber inside oil injector body, main fuel feed hole communicates with pressure accumulation chamber, current limliting Valve module is arranged in pressure accumulation chamber, and electromagnetic valve component, needle valve assembly are installed in oil injector body lower end successively, and tight cap is located at solenoid valve block Outside part, needle valve assembly, the mode that the upper end of tight cap is connected through a screw thread is connected with oil injector body bottom；

The current limliting valve module includes limit spring seat, current limliting piston, ball valve return spring holder, support and control sliding block, limit Position spring base, current limliting piston, ball valve return spring holder are arranged from top to bottom, and damping is installed between limit spring seat and current limliting piston Spring, support and control sliding block are arranged in ball valve return spring holder, set between the upper end of support and control sliding block and current limliting piston Mounting ball valve back-moving spring between ball valve, the lower end of support and control sliding block and ball valve return spring holder below, current limliting piston In piston blind hole and metering hole are set, axial central through hole is set in support and control sliding block, set in ball valve return spring holder humorous Shaken through hole and resonance throttle orifice, and transition oil pocket, piston blind hole are set between ball valve return spring holder and oil injector body below Connection pressure accumulation chamber and metering hole, metering hole are connected or disconnected under the control of ball valve with axial central through hole, and resonant through holes are harmonious The throttle orifice that shakes connects axial central through hole and transition oil pocket；

The electromagnetic valve component includes electromagnet, coil, armature, balance valve rod, valve seat, intermediate mass, is wound on electromagnet Coil, electromagnet top set magnetic valve return spring holder, armature, armature and magnetic valve return spring holder are set below electromagnet Between set magnetic valve back-moving spring, balance valve rod be located in valve seat, balance valve rod upper end be connected with armature, intermediate mass setting Below valve seat, formation balance valve-rod cavity between bottom, valve seat and the intermediate mass of valve rod is balanced, oil return is set in intermediate mass Hole, middle oil circuit, lower shape fuel feed hole, feedback oil circuit, middle oil circuit, feedback oil circuit are respectively communicated with balance valve-rod cavity, and spill port exists Balance and connect or disconnect with middle oil circuit and fuel tank under the control of valve rod；

The needle valve assembly includes needle-valve stop collar, orifice plate, needle-valve body, nozzle, and needle-valve stop collar is located in nozzle, orifice plate In needle-valve stop collar, the upper part of needle-valve body is located in needle-valve stop collar, and the lower part of needle-valve body is located in nozzle, orifice plate Form control chamber between needle-valve body, providing holes sheet reset spring in control chamber, bossing, lug boss are set in the middle part of needle-valve body Divide and needle-valve back-moving spring is set between the needle-valve stop collar above it, formed respectively between the upper surface of orifice plate and intermediate mass low Mouth, high-pressure mouth are pressed, throttle orifice is set in orifice plate, throttle orifice is respectively communicated with low pressure port and control chamber, the orifice plate needle-valve outside with it Side oil circuit is formed between stop collar, oil holding slot is formed between needle-valve body and nozzle, nozzle-end sets spray orifice；

Middle oil communication low pressure port, descending fuel feed hole connect high-pressure mouth, the upper end connection bridging oil of descending high-pressure oil passage Chamber, oil holding slot is connected through oil injector body, valve seat, intermediate mass, nozzle, descending fuel feed hole and feedback oil circuit are respectively communicated with lower horizontal high voltage Oil circuit.

The utility model can also include：

1st, during spray orifice oil spout, the fuel pressure of transition oil pocket declines, current limliting piston, ball valve, support and control sliding block it is overall to Bottom offset, and ball valve is not landed on ball valve return spring holder, metering hole communicates with axial central through hole；When the combustion of spray orifice outflow When oil quality exceedes threshold value, current limliting piston compresses ball valve and it is seated at ball valve return spring holder, metering hole and axial centre Through hole disconnects；When spray orifice stops oil spout, in the presence of ball valve back-moving spring, current limliting piston, ball valve and support and control sliding block are whole Body returns to initial position.

2nd, during coil electricity, balance valve rod moves upwards, and spill port and fuel tank are connected state, and the fuel oil in control chamber leads to Oil circuit and spill port oil return to fuel tank, needle-valve body are lifted up among crossing, and spray orifice opens oil spout；After coil blackout, valve rod is balanced Move downward, be crushed on intermediate mass upper surface in the effect of magnetic valve back-moving spring, spill port disconnects with fuel tank, while descending Fuel oil in high-pressure oil passage enters low pressure port by feeding back oil circuit through balance valve-rod cavity, middle oil circuit all the way, and another way is under Traveling oilhole enters high-pressure mouth, and orifice plate overcomes the elastic force of orifice plate back-moving spring to move downward, the fuel oil in low pressure port and high-pressure mouth Control chamber is entered by throttle orifice, side oil circuit, needle-valve body is taken a seat.

3rd, the diameter in the middle part of resonance throttle orifice is less than the diameter at its both ends, and less than the diameter of resonant through holes, resonance throttling Hole is consistent with the total length of resonant through holes axial direction.

Advantage of the present utility model is：The utility model employs the structure of orifice plate built in control chamber.This orifice plate Structure can significantly decrease the dynamic recirculating oil quantity of injection process intermediate fuel oil, significantly reduce energy loss, improve system Economy.The utility model employs pressure accumulation cavity configuration, can substantially improve the pressure oscillation of whole injection system, particularly Interfering with each other when can reduce each fuel injector oil spout.Current limliting valve module is employed in the utility model structure, is effectively avoided The generation of the abnormal conditions such as abnormal injection, and in current limliting valve module resonance structure is added, reduce fuel pressure Fluctuation, the reliability of fuel economy and fuel injector work is improved while the injection process for ensureing normal table.This practicality It is new that valve rod is balanced to adjust the switch of oil return circuit by solenoid valve control, be advantageous to improve response speed and the control of needle-valve Precision, there is provided flexible fuel injection characteristic, effectively improve the discharge stability and economy of diesel engine.Electromagnetic valve component Hydraulic feedback oil circuit is added inside intermediate mass, it has connected high-pressure oil passage and middle oil circuit so that needle-valve is opened slowly same When system can also be made to build pressure is rapid, improve the seating velocity of needle-valve, control fuel injector can quickly terminate oil spout.Spray nozzle part Divide internal hydraulic pressure balance, be poor without static pressure, realize function of the fuel injector without static leakage.

Brief description of the drawings

Fig. 1 is structural representation of the present utility model；

Fig. 2 is current limliting valve module schematic diagram；

Fig. 3 is electromagnetic valve component schematic diagram；

Fig. 4 is needle valve assembly schematic diagram；

Fig. 5 is A-A views.

Embodiment

Illustrate below in conjunction with the accompanying drawings and the utility model is described in more detail：

With reference to Fig. 1-5, the utility model include injector head 1, current limliting valve module 3, electromagnetic valve component 5, needle valve assembly 6, Tight cap 9, oil injector body 10.Injector head 1 by screw thread be connected and is arranged on oil injector body 10, and by being placed on Sealing ring 2 on oil injector body 10 is sealed.Main fuel feed hole 12 is set in injector head 1, and with the storage in oil injector body 10 Pressure chamber 11 connects.The lower section of pressure accumulation chamber 11 is provided with current limliting valve module 3.Current limliting valve module 3 is arranged on inside oil injector body 10, and its is main Structure includes back-up ring 13, damping spring 14, ball valve 16, support and control sliding block 17, ball valve back-moving spring 22, ball valve back-moving spring Seat 23, current limliting piston 24, limit spring seat 26.Wherein, metering hole 15 and piston blind hole 25 are processed on current limliting piston 24, axle Processed to central through hole 18 on support and control sliding block 17, this ensure that fuel oil can smoothly flow to lower section oil circuit.Fuel injector The lower section of body 10 is sequentially provided with electromagnetic valve component 5, needle valve assembly 6, and assembly connection is carried out by tight cap 9.Electromagnetic valve component 5 is mainly tied Structure include magnetic valve return spring holder 27, coil 28, armature 29, valve seat 30, intermediate mass 34, balance valve rod 36, electromagnet 37, Magnetic valve back-moving spring 38.Armature 29 and the balance combination of valve rod 36 are arranged on inside valve seat 30.Feed back oil circuit 31, spill port 31, Descending fuel feed hole 32, middle oil circuit 34 etc. are processed inside intermediate mass 35.The primary structure of needle valve assembly 6 positioned at fuel injector bottom Including orifice plate 40, orifice plate back-moving spring 41, needle-valve stop collar 42, needle-valve body 43, nozzle 44, needle-valve back-moving spring 45.Intermediate mass 35 form control chamber 46 with needle-valve stop collar 42 and needle-valve body 43.Orifice plate 40 is positioned in control chamber 46.Needle-valve body 43 is arranged on In nozzle 44, the upper end of needle-valve body 43 for being cased with needle-valve back-moving spring 45 is arranged in needle chamber, needle-valve body 43 and nozzle 44 it Between set oil holding slot 8.

Fig. 1 is a kind of overall structure diagram of the resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback of the utility model, Pressure accumulation chamber 11 is provided with oil injector body 10, pressure accumulation chamber 11 is connected with the main fuel feed hole 12 on injector head 1.In current limliting piston 24 The metering hole 15 that oil pocket passes sequentially through piston blind hole 25 and is opened in thereon is connected with pressure accumulation chamber 11.Injector head 1 and fuel injector Body 10 is assembled by threaded line, and sealing ring 2 is sealed the two.When the high pressure fuel that conveying is come in passes through main fuel feed hole When inside 12 entrance fuel injectors, current limliting valve module 3 can be passed through downwards by the fuel oil in pressure accumulation chamber 11.Fuel oil is from current limliting valve module Descending high-pressure oil passage 4, which is flowed through, after 3 outflows enters control chamber 46 and oil holding slot 8.The lower section of oil injector body 10 has been sequentially arranged magnetic valve Component 5, needle valve assembly 6.In electromagnetic valve component 5, armature 29 is controlled by electromagnetic force and balances lifting and falling for valve rod 36 Seat.When coil 28 is powered, balance valve rod 36 is lifted up, and spill port 32 is opened, and the intermediate fuel oil of control chamber 46 flows through throttling successively Hole 47 and middle oil circuit 34, pass through the draining of spill port 32.Therefore the fuel pressure of control chamber 46 declines, with pressure shape in oil holding slot 8 Into fuel oil pressure difference so that needle-valve body 43 lifts, fuel injection beginning.During being somebody's turn to do, needle-valve stop collar 42 plays limitation needle-valve body 43 The effect of displacement.When coil 28 powers off, when balance valve rod 36 is taken a seat downwards, spill port 32 is closed, and a part of fuel oil passes through feedback Oil circuit 31 flows through balance valve rod 36, middle oil circuit 34 is entering the throttle orifice 47 in needle valve assembly 6；Another part fuel oil passes through Descending fuel feed hole 33 enters the high-pressure mouth 39 of side downstream, and high-pressure mouth 39 forms an annular oil in the rear surface of intermediate mass 35 Groove, surround circular low pressure port 49.Because the oil-feed for feeding back oil circuit 31 causes the oil pressure of circular low pressure port 49 to raise, annular oil groove Pressure difference is formed with oil pressure in control chamber 46 so that orifice plate 40 overcomes orifice plate to answer with the oil pressure of the high pressure fuel in circular low pressure port 49 The spring force of position spring 41 moves downward, and opens the side oil circuit 48 of orifice plate 40.Flow through middle oil circuit 33 and descending fuel feed hole 32 high pressure fuel quickly enters control chamber 46 by annular side oil circuit 48 and the two-way of throttle orifice 47, and quickly establishes oil pressure, So that needle-valve body 43 is taken a seat, so as to terminate injection process.Needle-valve body 43 is arranged on inside nozzle 44, and by needle-valve back-moving spring 45 Compress.Nozzle 44 and electromagnetic valve component 5 are all arranged on inside tight cap 9, and are fastened by oil injector body 10 and threaded line.Needle-valve body 43 internal hydraulic pressures balance, are poor without static pressure, realize function of the fuel injector without static leakage.

Fig. 2 is the utility model flow-limiting valve components structural representation.It by back-up ring 13, damping spring 14, ball valve 16, Support and control sliding block 17, ball valve return spring holder 23, current limliting piston 24, limit spring seat 26 etc. form.Current limliting valve module 3 passes through Pressure accumulation chamber 11 is arranged on inside oil injector body 10.Back-up ring 13 not only serves position-limiting action, Er Qieyu to overall current limliting valve module 3 Limit spring seat 26 is coordinated, on the one hand the spring base as damping spring 14, on the other hand limits current limliting piston 24 Maximum displacement.Under the effect of the initial tension of spring of damping spring 14 and ball valve back-moving spring 22, ball valve 16 is the same as current limliting piston 24 Lower surface and the upper surface of support and control sliding block 17 coordinate.Spring masterpiece of the ball valve return spring holder 23 in ball valve back-moving spring 22 Under, bottom is pressed in, the face of taking a seat of ball valve 16 is formed at its top variable cross-section.High pressure fuel is entered by pressure accumulation chamber 11 to be limited The piston blind hole 25 in piston 24 is flowed, flows through the axial central through hole 18 that metering hole 15 enters support and control sliding block 17.By axle Enter transition oil pocket 20 by resonant through holes 19 and resonance throttle orifice 21 to the fuel oil that central through hole 18 flows out.Processed by setting Resonant through holes 19 and resonance throttle orifice 21, reduce the amplitude of the fuel pressure wave by holes.In addition, the resonance throttling of processing Have that a sector hole footpath is smaller compared with resonant through holes 19 in hole 21, therefore restriction effect is stronger, result in the fuel flow rate flowed through from holes It is different so that the fuel pressure wave of script same-phase generates phase difference, is cancelled out each other after two bursts of fuel pressure wave superpositions, and then So that pressure oscillation greatly reduces.Lead to lower section oil circuit from the fuel oil that transition oil pocket 20 flows out by descending high-pressure oil passage 4.Work as spray During oily device normal work, spray orifice 9 sprays fuel oil so that the fuel pressure in transition oil pocket 25 declines.Because metering hole 15 is to combustion The throttling action of oil so that the fuel pressure rise in the piston blind hole 25 and pressure accumulation chamber 11 in current limliting piston 24, with bridging oil The fuel pressure of chamber 20 forms pressure difference, therefore current limliting piston 24, ball valve 16 and the three of support and control sliding block 17 are overall to bottom offset, this Certain compensation just has been carried out to the fuel oil of fuel injector injection, but not has caused ball valve 16 to be landed in ball valve return spring holder 23 On.When oil spout is stopped, as fuel oil flows through metering hole 15, the pressure difference of the upper and lower surface of current limliting piston 24 can be gradually reduced, In the presence of ball valve back-moving spring 22, current limliting piston 24, ball valve 16 and the three of support and control sliding block 17 return to initial bit again Put.When the continual injection fuel oil of spray orifice 7, the fuel oil quality of outflow exceedes threshold value so that abnormal work shape occurs in fuel injector During state, the oil pressure of the lower section transition oil pocket 20 of current limliting piston 24 declines rapidly, forms pressure difference up and down, causes current limliting piston 24 to compress Ball valve 16 is landed on ball valve return spring holder 23, prevents fuel oil to continue to circulate.Due to having cut off fuel delivery, fuel injector stops Only work, the occurrence of this just reduces abnormal injection to a certain extent, improve fuel economy and fuel injector work Stability.

Fig. 3 is the utility model electromagnetic valve component part-structure schematic diagram.It is by magnetic valve return spring holder 27, coil 28th, armature 29, valve seat 30, intermediate mass 35, balance valve rod 36, electromagnet 37, magnetic valve back-moving spring 38 etc. are formed.Magnetic valve is answered Position spring base 27, coil 28, electromagnet 37 and magnetic valve back-moving spring 38 are built in oil injector body 10, and wherein magnetic valve resets Spring base 27 is by screw threads for fastening in magnetic valve top.Magnetic valve back-moving spring 38 is in magnetic valve return spring holder 27 and armature 29 therebetween, and armature 29 and balance valve rod 36 are arranged on inside the valve seat 30 of the lower section of oil injector body 10.Intermediate mass 35 is in valve The lower section of seat 30.When fuel injector commencement of fuel injection, coil 28 is powered, and forms magnetic loop with armature 29 and electromagnet 37, produces electromagnetism Power, balance valve rod 36 is attracted to move up, the spill port 32 in intermediate mass 35 is opened.At this moment, the fuel oil in control chamber 46 is successively By middle oil circuit 34 and the oil return of spill port 32 to fuel tank, due to the throttling action of middle oil circuit 34, the internal combustion oil pressure of control chamber 46 Power declines more slowly, and the upper surface of needle-valve body 43, which is pressurized, to be reduced, and pressure difference is formed with the fuel pressure in oil holding slot 8.Under differential pressure action, Needle-valve body 43 slowly lifts upwards, and spray orifice 7 opens oil spout.When fuel injector stops oil spout, coil 28 powers off, due to the He of armature 29 Balance valve rod 36 is closely as one, therefore the initial tension of spring effect that they are jointly subjected to magnetic valve back-moving spring 38 is transported downwards It is dynamic, and be pressed on the upper surface of intermediate mass 35, and blocked spill port 32.At the same time, there is two-way oil-feed in intermediate mass 35, Be all the way by feed back oil circuit 31 flow through middle oil circuit 34 enter lower section needle valve assembly；Another way is by descending fuel feed hole 33 Into lower section oil circuit.In whole injection process, there is high pressure fuel to enter top oil pocket by feeding back oil circuit 31 always, reduce control The oil pressure fall off rate of chamber 46 processed so that the pressure drop at oil spout initial stage of control chamber 46, which diminishes, to slow down, and reduces the production of nitrogen oxides It is raw；And in end of injection, voltage built-up rate of the normal single fuel feed hole to control chamber 46 is improved, improves the speed of taking a seat of needle-valve Degree, and optimize needle-valve response speed.

Fig. 4 is the utility model needle valve assembly part-structure schematic diagram.The primary structure of needle valve assembly 5 includes orifice plate 40, hole Sheet reset spring 41, needle-valve stop collar 42, needle-valve body 43, nozzle 44, needle-valve back-moving spring 45.Before fuel injection beginning, whole control Chamber 46 processed is to be in hydrodynamic equilibrium state, is each filled with high pressure fuel.And orifice plate 40 is due to by the spring pre-tightening of orifice plate back-moving spring 41 The effect of power is jacked up, and blocks high-pressure mouth 39.When coil 28 is powered, after the balance valve rod 36 of magnetic valve lifts, spill port 32 Open.Fuel oil in control chamber 46 flows through throttle orifice 47 and the progress oil return of middle oil circuit 34 on orifice plate 40 successively.With control The fuel pressure of chamber 46 declines, and needle-valve body 43 overcomes the initial tension of spring of needle-valve back-moving spring 45 to be lifted up, commencement of fuel injection. In injection process, the presence of throttle orifice 47 make it that the fuel pressure in control chamber 46 is higher than the fuel pressure in middle oil circuit 34, Fuel pressure in the annular oil groove for making a concerted effort to be enough to overcome high-pressure mouth 39 to be formed of its pressure difference value and spring force, so, Orifice plate 40 is pressed on the lower surface of intermediate mass 35 always, has blocked the annular oil groove that descending fuel feed hole 33 enters side downstream, The entrance of high pressure fuel is prevented, effectively reduces the high pressure fuel amount that low-pressure reservoir is flowed back in injection process.When coil 28 Power-off, after the balance valve rod 36 of magnetic valve is taken a seat, spill port 32 is plugged.Oil circuit 31 is fed back due to existing, by feeding back oil circuit 31 high pressure fuels entered cause the oil pressure of middle oil circuit 34 to rise until orifice plate 40 is opened.The inner high voltage fuel oil of high-pressure mouth 39 is the same as control Fuel pressure in chamber 46 processed forms pressure difference so that orifice plate 40 overcomes the initial tension of spring of orifice plate back-moving spring 41, under orifice plate 40 Move and open, at the same time, the peripheral circular side oil circuit 48 of orifice plate 40 is opened.High pressure fuel flows through descending fuel feed hole 33 all the way, and one Road flows through feedback oil circuit 31, middle oil circuit 34 successively, finally all enters control by throttle orifice 47 and the two-way of annular side oil circuit 48 Chamber 46 processed, oil pressure is quickly established in control chamber 46, and needle-valve is taken a seat rapidly, and oil spout stops.

Fig. 5 is the section A-A enlarged drawing of needle-valve body 43.Its arcwall face can be very good to play guide effect.

From the above-mentioned course of work, a kind of spray of the pressure accumulation orifice-plate type electric-controlled fuel injector with hydraulic feedback of the utility model During oil, the structure of orifice plate 40 that is built in needle valve assembly 6 substantially reduces the dynamic recirculating oil quantity in injection process, ensures The characteristics of On Fluctuations oil returns.Pass through the internal feedback oil circuit 31 of electromagnetic valve component 5 and the two-way oil-feed of descending fuel feed hole 33 and pin The two-way oil-feed of the throttle orifice 47, annular side oil circuit 48 of the orifice plate 40 of valve module 6, greatly improved building for control chamber 46 and presses through Journey, improve the response speed that needle-valve is taken a seat.In addition, oil injector body 10 built with current limliting valve module 3, effectively prevent different The lasting progress of normal oil spout state, wherein, the addition of resonance structure effectively reduces fuel pressure fluctuation, ensure that the course of work Stability and fuel economy.Whole injection process uses solenoid valve control, utilizes fortune of the electromagnetic force with acting balancing valve bar 36 It is dynamic, realize to injection process fast response time, control accuracy is high, the requirement of variable fuel injection characteristic.The utility model is applied to When on common rail system, under big oil mass spray regime, common rail pressure fluctuation can be effectively reduced using the structure of pressure accumulation chamber 11, so as to Reduce the uniformity of each cylinder injection process and stability declines the generation of phenomenon.

Claims (5)

1. a kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback, it is characterized in that：Including injector head, oil injector body, limit Valve module, electromagnetic valve component, needle valve assembly, descending high-pressure oil passage are flowed, injector head is arranged on above oil injector body, injector head Inside sets main fuel feed hole, sets pressure accumulation chamber inside oil injector body, main fuel feed hole is communicated with pressure accumulation chamber, and current limliting valve module is arranged on In pressure accumulation chamber, electromagnetic valve component, needle valve assembly are installed in oil injector body lower end successively, and tight cap is located at electromagnetic valve component, needle valve assembly Outside, the mode that the upper end of tight cap is connected through a screw thread are connected with oil injector body bottom；

The current limliting valve module includes limit spring seat, current limliting piston, ball valve return spring holder, support and control sliding block, spacing bullet Spring abutment, current limliting piston, ball valve return spring holder are arranged from top to bottom, and damping bullet is installed between limit spring seat and current limliting piston Spring, support and control sliding block are arranged in ball valve return spring holder, and ball is set between the upper end of support and control sliding block and current limliting piston Mounting ball valve back-moving spring between valve, the lower end of support and control sliding block and ball valve return spring holder below, in current limliting piston Piston blind hole and metering hole are set, axial central through hole is set in support and control sliding block, resonance is set in ball valve return spring holder Transition oil pocket is set between through hole and resonance throttle orifice, ball valve return spring holder and oil injector body below, and piston blind hole connects Logical pressure accumulation chamber and metering hole, metering hole are connected or disconnected under the control of ball valve with axial central through hole, resonant through holes and resonance Throttle orifice connects axial central through hole and transition oil pocket；

The electromagnetic valve component includes electromagnet, coil, armature, balance valve rod, valve seat, intermediate mass, wound around coil on electromagnet, Magnetic valve return spring holder is set above electromagnet, armature is set below electromagnet, between armature and magnetic valve return spring holder Magnetic valve back-moving spring is set, and balance valve rod is located in valve seat, and balance valve rod upper end is connected with armature, and intermediate mass is arranged on valve Seat lower section, balance and balance valve-rod cavity formed between bottom, valve seat and the intermediate mass of valve rod, set in intermediate mass spill port, Middle oil circuit, lower shape fuel feed hole, feedback oil circuit, middle oil circuit, feedback oil circuit are respectively communicated with balance valve-rod cavity, and spill port is balancing Connect or disconnect with middle oil circuit and fuel tank under the control of valve rod；

The needle valve assembly includes needle-valve stop collar, orifice plate, needle-valve body, nozzle, and needle-valve stop collar is located in nozzle, and orifice plate is located at In needle-valve stop collar, the upper part of needle-valve body is located in needle-valve stop collar, and the lower part of needle-valve body is located in nozzle, orifice plate and pin Form control chamber between valve body, providing holes sheet reset spring in control chamber sets bossing in the middle part of needle-valve body, bossing with Needle-valve back-moving spring is set between the needle-valve stop collar above it, low pressure is formed respectively between the upper surface of orifice plate and intermediate mass Mouthful, high-pressure mouth, throttle orifice is set in orifice plate, and throttle orifice is respectively communicated with low pressure port and control chamber, and orifice plate limits with its outside needle-valve Side oil circuit is formed between the set of position, oil holding slot is formed between needle-valve body and nozzle, nozzle-end sets spray orifice；

Middle oil communication low pressure port, descending fuel feed hole connect high-pressure mouth, the upper end connection transition oil pocket of descending high-pressure oil passage, warp Oil injector body, valve seat, intermediate mass, nozzle connection oil holding slot, descending fuel feed hole and feedback oil circuit are respectively communicated with descending high-pressure oil passage.

2. a kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback according to claim 1, it is characterized in that：Spray orifice sprays When oily, the fuel pressure of transition oil pocket declines, and current limliting piston, ball valve, support and control sliding block are overall to bottom offset, and ball valve does not fall On ball valve return spring holder, metering hole communicates seat with axial central through hole；When the fuel oil quality of spray orifice outflow exceedes threshold value, Current limliting piston compresses ball valve and it is seated at ball valve return spring holder, and metering hole disconnects with axial central through hole；Spray orifice stops During oil spout, in the presence of ball valve back-moving spring, current limliting piston, ball valve and support and control sliding block integrally return to initial position.

3. a kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback according to claim 1 or 2, it is characterized in that：Line When circle is powered, balance valve rod moves upwards, and spill port and fuel tank be connected state, the fuel oil in control chamber by middle oil circuit with Spill port oil return to fuel tank, needle-valve body is lifted up, and spray orifice opens oil spout；After coil blackout, balance valve rod resets in magnetic valve The effect of spring moves downward, and is crushed on intermediate mass upper surface, and spill port disconnects with fuel tank, while in descending high-pressure oil passage Fuel oil enters low pressure port by feeding back oil circuit through balance valve-rod cavity, middle oil circuit all the way, and another way is entered by descending fuel feed hole High-pressure mouth, orifice plate overcome the elastic force of orifice plate back-moving spring to move downward, and the fuel oil in low pressure port and high-pressure mouth passes through throttle orifice, side Face oil circuit enters control chamber, and needle-valve body is taken a seat.

4. a kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback according to claim 1 or 2, it is characterized in that：It is humorous The diameter to shake in the middle part of throttle orifice is less than the diameter at its both ends, and less than the diameter of resonant through holes, resonance throttle orifice and resonant through holes The total length of axial direction is consistent.

5. a kind of resonance orifice-plate type electric-controlled fuel injector with hydraulic feedback according to claim 3, it is characterized in that：Resonant section Diameter in the middle part of discharge orifice is less than the diameter at its both ends, and less than the diameter of resonant through holes, resonance throttle orifice and resonant through holes axial direction Total length it is consistent.