The model utility content
The purpose of the utility model is that under the situation that does not increase the sparger diameter, to make diameter be that 14mm and above sparger can bear 1800bar and above allowable pressure.
For this reason, the utility model provides a kind of fuel injector of internal-combustion engine, comprising: ejector body, and portion is formed with the spring receiving hole that holds spring within it, and said ejector body has first longitudinal axis, and said spring receiving hole has second longitudinal axis; The nozzle body that links to each other with ejector body, portion accommodates needle-valve within it, and said nozzle body has the 3rd longitudinal axis; Be formed at the high pressure oil pipeline in the said ejector body; Said second longitudinal axis is put towards that lateral deviation that deviates from said high pressure oil pipeline with respect to said first longitudinal axis, and with needle-valve that nozzle body contacts on be partly with anti-scuff coating at least.
According to a preferred embodiment, all have anti-scuff coating at the two ends of the needle-valve that contacts with nozzle body.
According to a preferred embodiment, between ejector body and nozzle body, be provided with spacer element, be formed with on said ejector body and the surface that said spacer element contacts and be used to collect the letdown tank that leads to said spring receiving hole of revealing fuel.
According to a preferred embodiment, in the plane perpendicular to said first longitudinal axis, said letdown tank has approximate cross-like cross-section.
According to a preferred embodiment, said first longitudinal axis and said the 3rd longitudinal axis be conllinear substantially.
According to a preferred embodiment, said fuel injector has one or more spouts.
According to a preferred embodiment, said fuel injector is the fuel injector that is used for non-common rail system.
According to a preferred embodiment, said fuel injector is that external diameter is 14mm and above MFI Mechanical Fuel Injection device.
According to a preferred embodiment, said high pressure oil pipeline comprises the straightway that is communicated with petrolift that is formed in the ejector body, is formed at the oblique line section that is communicated with needle-valve in the nozzle body.
According to a preferred embodiment, said fuel injector also is included in the filter that is located at the high pressure oil pipeline upper reaches in the said ejector body.
According to the sparger of the utility model, concrete diameter is the sparger of 14mm and above (like 17mm), and through adopting eccentric spring structure, the on high-tension side wall thickness of sparger increases, and makes sparger can bear 1800bar or higher pressure, has satisfied requirement.
Through on sealing surfaces, adopting approximate cross seal groove structure; Make before the edge that arrives matching surface, to be directed into seal groove structure after the fuel leak bear high pressure, realized under the prerequisite that does not increase mounting torque, amount of leakage being reduced to the purpose in the acceptable scope.
According to the sparger of the utility model, through with the end of the contacted needle-valve of nozzle body on application of coatings, reduced the friction factor of the contact surface between nozzle body and the needle-valve, thereby reduced mechanical wear, prolong the working life of sparger.
Embodiment
Preferred embodiment according to the utility model is described with reference to the drawings below.It should be noted that accompanying drawing only is used for illustrating the principle of the utility model, so possibly not draw in proportion.
Fuel injector according to the utility model can be the sparger that in non-common rail system, uses.
Fuel injector 100 according to the preferred embodiment of the utility model is as shown in Figure 1, and Fig. 2 is the enlarged view of broken circle part among Fig. 1.
Fuel injector 100 comprises two major components: ejector body 2 and the nozzle body 18 that is being kept by ejector body 2.Usually, nozzle body 18 by means of link for example retention nut 14 be connected securely on the ejector body 2, and be separated with spacer element 16 between between nozzle body 18 and the ejector body 2.
Be formed with the pressure chamber 9 of ccontaining fuel under high pressure in the nozzle body 18, and holding needle-valve 20.
Identical with traditional fuel injector, be installed in cylinder head according to the fuel injector 100 of the utility model, ejector body 2 has threaded end 11, is used for being connected with the pump of fueling.
On this threaded end 11, be provided with fuel inlet hole 1, said fuel inlet hole 1 is passed by the longitudinal axis X1 of ejector body 2, and extends at angle in the ejector body 2 with the longitudinal axis X1 of ejector body 2.
Be provided with filter 3 in the space in fuel inlet hole 1 extends to ejector body 2.Filter 3 makes that the large particle in the fuel is stopped, can not flow through sparger and is injected in the firing chamber of internal-combustion engine.
In ejector body 2, be provided with the high-pressure oil passage cardinal principle straightway 4 of cardinal principle along the longitudinal direction extension of ejector body 2; Said high-pressure oil passage cardinal principle straightway 4 quilts are from the amesiality setting of the longitudinal axis of ejector body 2; Thereby a side that is provided with said cardinal principle straightway 4 is called as the high pressure side, and an opposite side is called as low voltage side.
High-pressure oil passage straightway 4 substantially passes through hole 40 extensions in the spacer element 16 that is formed between nozzle body 18 and the ejector body 2.
The high-pressure oil passage tilting section 8 that is formed in the nozzle body 18 is communicated with high-pressure oil passage cardinal principle straightway 4 through through hole 40, and directly is communicated with the pressure chamber 9 of nozzle body 18.
Therefore, the fuel that pump is supplied with gets into the pressure chamber 9 of nozzle bodies 18 through the filtration of filter 3 through high-pressure oil passage cardinal principle straightway 4, through hole 40, high-pressure oil passage tilting section 8.
Nozzle body 18 has longitudinal axis X2, and in the sparger 100 according to the utility model, the longitudinal axis X2 of nozzle body 18 and the longitudinal axis X1 of ejector body 2 be conllinear substantially.
Nozzle body 18 has spout 10, and spout 10 can be a plurality of.
In ejector body 2, be formed with the spring receiving hole 15 of end sealing, the other end of spring receiving hole 15 is open facing to spacer element 16.
In ejector body 2, extend substantially the throat 13 that extends along the longitudinal axis X1 of ejector body 2 at the closed end of spring receiving hole 15, and the hole 12 that passage 13 is communicated with the outside.
Spring 6 is placed in the spring receiving hole 15, and an end is resisted against on the pad 5 of the closed end that is positioned over spring receiving hole 15, and the other end is resisted against on the spacer element 16 through spring seat 7.
Spring seat 7 comprises and extends to cylindrical portion 30, the disc portion 32 that is connected with cylindrical portion 30 in the spring 6 and be positioned at disc portion 32 and curved portion 33 cylindrical portion 30 opposite sides.Spring 6 is resisted against on the disc portion 32 of spring seat 7 in cylindrical portion 30 1 sides, and the curved portion 33 of spring seat 7 is passed the through hole that is formed on the corresponding section in the spacer element 16 and acted on the needle-valve 20.
Behind the pressure chamber 9 of the fuel entering nozzle body 18 that pump is supplied with; Rising along with the fuel pressure in the pressure chamber 9; Needle-valve 20 is being resisted the pre-compression force of spring 6 and is being raise, thus needle-valve 20 unlatchings, and fuel under high pressure is ejected in the firing chamber with very high kinetic energy through spout 10.Subsequently, the fuel pressure in the pressure chamber 9 reduces.Needle-valve 20 moves down under the pressure effect of spring 6, thereby needle-valve 20 is closed to spray and stopped.So, accomplished the circulation that sparger sprays.When fuel pressure raises and needle-valve 20 when being opened once more once more, next spraying cycle begins immediately.
Alternatively, can adjust the pre-compression force of spring 6 through the adjustment copper packing that uses different-thickness.
In order to make this diameter is that the sparger of 14mm and above (like 17mm) can bear 1800bar or higher high side pressure; Those skilled in the art are easy to expect increasing the wall thickness of sparger; Yet; Because the space of ejector body 2 is limited, so thereby adopted the eccentric mode that spring receiving hole 15 increases the high pressure side wall thickness that is provided with according to the sparger of the utility model.
Shown in the enlarged view among Fig. 2, the longitudinal axis X3 of the spring receiving hole 15 of putting spring 6 is from the longitudinal axis X1 of ejector body 2, and just from the longitudinal axis X2 of nozzle body 18, biasing one is apart from e.
Like this, the longitudinal axis X3 of bias spring receiving hole 15 makes that ejector body 2 is L1 at the wall thickness of high pressure one side, is L2 at the wall thickness of low pressure one side, and as shown in fig. 1, wall thickness L1 is greater than wall thickness L2.With the longitudinal axis X1 of the longitudinal axis X3 of spring receiving hole 15 and ejector body 2 and therefore compare with the sparger of the longitudinal axis X2 conllinear of nozzle body 18, so the sparger 100 of structure can bear higher pressure because the high pressure side wall thickness increases.
Employing makes the mode of the longitudinal axis X3 of spring receiving hole 15 from the longitudinal axis X1 biasing of ejector body 2; Reached the effect that increases sparger high pressure side wall thickness, made that diameter is that the sparger of 14mm and above (like 17mm) can bear 1800bar or higher pressure.Simultaneously, sparger still can be complementary with the cylinder head of same size.
Those skilled in the art will readily appreciate that along with the rising of sparger fuel pressure, for example up to 1800bar or higher, fuel leak becomes the problem that can not be ignored.So, to the also corresponding raising of the seal request between the matching surface of the member that matches in the sparger 100, for example between the matching surface of nozzle body 18 and spacer element 16, the perhaps sealing between the matching surface of spacer element 16 and ejector body 2.
Normally, the mounting torque through retention nut 14 can satisfy the sealing between these matching surfaces.Yet the fuel pressure that sparger 100 bears has raise, and the mounting torque of retention nut 14 can not unrestrictedly increase, and mounting torque too conference destroys nozzle body.
For with the limit leakage between these matching surfaces in acceptable scope, adopt the sealed surface texture of letdown tank according to the sparger of the utility model 100 with approximate cross cross section, concrete with reference to figure 3-4.
The enlarged view at A-A place has been shown among Fig. 3; Fig. 3 A and Fig. 3 B are Y and Z enlarged views partly among Fig. 3; Fig. 4 is the sectional drawing along A-A; Be clearly shown the letdown tank 22 of the approximate cross cross section that on the sealing surfaces of ejector body 2, forms, letdown tank 22 is communicated with spring receiving hole 15 fluids.Positioning hole when in addition, the 23 expression ejector body 2 of the reference mark among Fig. 4 are installed.
High-pressure oil passage straightway 4 substantially is directed in the letdown tank 21 that is formed on the ejector body 2 before at the edge that arrives ejector body 2 at the fuel of revealing on the surface between ejector body 2 and the spacer element 16.
Equally, the fuel of revealing between the matching surface of nozzle body 18 and spacer element 16 was directed into letdown tank 22 before the arrival edge is leaked to sparger 100 outsides, get into low pressure recycle then.
Through the design of the letdown tank on the above-mentioned sealing surfaces, make the fuel of revealing before the edge that arrives injector body 2, be collected in the letdown tank, be issued to the amount of leakage purpose of fuel limitation in the situation of the mounting torque that does not increase retention nut 14.
Further; Employing is according to eccentric spring receiving hole 15 structures of the sparger 100 of the utility model; Since the axis X 3 of the spring 6 of a side effect of spring seat 7 with at the axis X 2 of the needle-valve 20 of the opposite side effect of spring seat 7 conllinear not, so may between needle-valve 20 and nozzle body 18, produce lateral force.This has increased between the end 25 of nozzle body 18 and needle-valve 20 and the mechanical wear between the end 26 of nozzle body 18 and needle-valve 20.
Sparger 100 according to the utility model has solved the problem that reduces above-mentioned mechanical wear.Fig. 5 shows the longitudinal sectional drawing of nozzle segment, and Fig. 6 is the view of needle-valve 20 parts of Fig. 5.
Particularly, on the end of needle-valve 20 25 and end 26, have anti-scuff coating respectively.Preferably, coating is metal-free carbon property material, for example C2.1.In one embodiment, said coating is a diamond-like coating.
Coating can be applied on the end 25 or end 26 of needle-valve 20, also can be applied to simultaneously on the outer surface of end 25 and end 26 of needle-valve 20.Can further reduce the mechanical wear of needle-valve 20 like this.
On needle-valve 20, form coating, when reducing mechanical wear, also play the effect of the respective surfaces hardness that improves needle-valve 20.
Coating can be applied on the target surface through any suitable spraying coating process, for example hot-spraying technique etc.
Preferably, the thickness of coating should be even as far as possible, reduces mechanical wear with the friction factor that reduces matching surface better.Usually, the thickness of coating is not more than 2 microns, and preferably, the thickness of coating is between the 0.5-1.7 micron.
Sparger according to the utility model; Concrete diameter is the sparger of 14mm and above (like 17mm); For example external diameter is 14mm and above MFI Mechanical Fuel Injection device; Through adopting eccentric spring structure, the on high-tension side wall thickness of sparger increases, and makes sparger can bear 1800bar or higher pressure.
In addition; Through on sealing surfaces, adopting approximate cross seal groove structure; Make before the edge that arrives matching surface, to be directed into seal groove structure after the fuel leak bear high pressure, realized under the prerequisite that does not increase mounting torque, amount of leakage being reduced to the purpose in the acceptable scope.
At last; According to the sparger of the utility model, through with the end of nozzle body 18 contacted needle-valves and end on application of coatings, reduced the friction factor of the contact surface between nozzle body and the needle-valve; Thereby reduced mechanical wear, increase the working life of sparger.
Preferred implementation according to the utility model is described above, and those skilled in the art should be appreciated that foregoing description only is exemplary, is not intended to limit the present invention.It is 14mm and above sparger that the above-mentioned characteristic of the utility model not only is applied to diameter, also is applicable to the sparger of other type, for example, has the sparger of two or more adjustment springs, has the sparger of a plurality of spouts, or the like.Again for example, be used to guide the shape of the letdown tank of revealing fuel to be not limited to above-mentioned approximate cross brilliance door, but the shape of letdown tank and the degree of depth can change according to concrete application.Under the prerequisite of spirit that does not depart from the utility model and scope, can carry out various modifications and variation to the foregoing description.