CN103717872B - Petrolift - Google Patents

Abstract

There is provided a kind of petrolift (1), for making the fuel pressure boost in high pressure fuel injection system. Described petrolift (1) comprises pump head (7), pumping element (8), framework (12) and cover (3). Pump head (7) has the pumping chamber (7a) being arranged to and receiving the fuel treating supercharging. Pumping element (8) is arranged to the motion in response to driving element (10) and to-and-fro movement, this pumping element (8) partly limits described pumping chamber (7a), thus in use when described pumping element (8) to-and-fro movement, the power transmitted from described driving element (10) is applied to the fuel in described pumping chamber (7a), so that fuel pressure boost. Framework (12) is arranged to and supports described driving element (10) and described pump head (7). Cover (3) is defined for the internal space (5) holding fluid, wherein, described framework (12) at least partially, described driving element (10) at least partially with being accommodated at least partially in described cover (3) of described pumping element (8).

Description

Petrolift

Technical field

The present invention relates to petrolift field. Specifically, the present invention relates to for by the high pressure fuel pump of high-pressure fuel supply to fuel injector. But more specifically nonexclusively, the present invention relates to the shell for this kind of pump.

Background technology

Fuel injection system for modern internal combustion engines (especially adopting the engine of ignition) comprises multiple fuel injector, and described fuel injector is arranged to and the fuel spray of atomization is sent to each combustion chamber to burn.

In order to improve fuel in the in-engine atomization adopting ignition, it is preferable that atomized fuel as much as possible. Spraying of ruel largely improves the efficiency of combustion processes, and this then improves fuel efficiency and reduces the noxious emission of the such as carbon monoxide that combustion processes produces. The most common methods improving atomization is the pressure increasing fuel to be sprayed. Thus, existed the constant demand manufacturing the pump that fuel pressure boost can be made to arrive elevated pressures.

Known high-pressure pump adopts the pumping element of such as steel plunger, and the to-and-fro movement in the guiding hole of snug fit of this steel plunger, drives this plunger by drive shaft. Thus, when drive shaft rotates, its revolving force is passed to plunger, so that plunger to-and-fro movement in guiding hole. Fuel enters the pumping chamber of the end in guiding hole, applies pressurized energy along with reciprocating plunger to pumping chamber afterwards and is pressurized. Then, fuel is forced through transmission valve and enters high pressure rail, is sprayed by fuel injector to be ready to. The parts of pump are supported by shell. DE102008007028 discloses a kind of petrolift comprising panel assembly, and this panel assembly compensates the power between pumping element and driving element.

In order to increase the pressure of the fuel that high pressure fuel pump can provide, it is necessary to will more multi-energy be input in system by the drive shaft rotated, so that plunger applies bigger power to fuel. Thus, when the pressure increase that pump can provide, due to the increase of the physical energy of use in pump, the relative intensity of pump case also increases.

Usually fuel under high pressure pump case is manufactured with cast steel, to provide the intensity needed for stress that withstand high pressures petrolift stands. The pump that can produce the more fuel of high pressure owing to developing, therefore the thickness of outer steel shell also increases, to tolerate the relative increase of stress.

The thickness increasing cast steelpump shell causes pump heavier. Thus, it may also be useful to the fuel efficiency of the vehicle of this pump reduces because it must deliver heavier parts. In addition, along with the thickness of cast steelpump shell increases, the overall dimensions of pump also increases.

Expect the high pressure fuel pump providing weight and size all to reduce. This is specifically relevant to " environmental efficiency " concept vehicle, and wherein, the reduction of vehicle overall weight is the key element raised the efficiency, thus to reduce the environmental influence of vehicle. Additionally, it is desirable to the size of minimumization pump, this is because this kind of pump occupies less space in vehicle.

Therefore, what embodiments of the invention were intended to alleviate at least in part in the problems referred to above is one or more.

Summary of the invention

According to the first aspect of the invention, it is provided that a kind of for making the petrolift of the fuel pressure boost in high pressure fuel injection system. Described petrolift comprises pump head, and this pump head has the pumping chamber being arranged to and receiving the fuel treating supercharging. Described petrolift also comprises and is arranged to the reciprocating pumping element in response to the motion of driving element. This pumping element partly limits described pumping chamber, thus in use when described pumping element to-and-fro movement, the power transmitted from described driving element is applied to the fuel in described pumping chamber, so that fuel pressure boost. Described petrolift also comprises the cover being arranged to the framework supporting described driving element and being defined for the internal space holding fluid. Described framework at least partially, described driving element at least partially with being accommodated at least partially in described cover of described pumping element. Therefore, this arranges provides gentlier, less pump.

Described framework provides the shell of pump together with cover.

Described framework can be arranged to and pump head and driving element are remained on fixed position relative to each other. This kind is arranged and is allowed petrolift correctly to operate. Specifically, very big power is delivered to pump head from driving element, so that by the fuel pressure boost in pump head to very high pressure. Therefore, framework needs to tolerate such power and keeps pump head and driving element to be in fixed position relative to each other, so that pump continues correctly to operate.

Described framework can be become by the material structure that the material that strength ratio structure cover is used is high. Framework is set to support pump head and driving element, and covers and be arranged for accommodation fluid. Thus, only framework must tolerate the very big power being delivered to pump head from driving element. Therefore, cover can be made up of the low material of strength ratio framework, this is because cover only must hold fluid. Alternatively, framework and cover can be manufactured from the same material, and framework can be made thicker than cover, to provide higher intensity. Preferably, framework is made of aluminum, this is because compared with other material, aluminium is relatively firm, and relative low with other material phase specific density.

Can be selected as the material of described framework and cover making these materials for described framework and cover specific function be optimum. Material for framework can be selected as making it have the high strength being enough to support the power being delivered to pump head from driving element. Material for cover can be selected for use in holding fluid.

Described framework can be formed by single-piece. Forming framework by single-piece can make framework firmer, this is because described framework does not have any joint that structure can be caused to weaken. In addition, framework can be formed by single-piece by extrusion process. This kind of extrusion process provides the easy approach manufacturing single-piece framework. In addition, this kind of extrusion process makes the additional feature of such as screw hole easily to be formed in framework.

Described cover can be formed by the material based on plastics. This kind of layout can cause weight saving and be easy to manufacture described cover.

Described framework can be arranged to for petrolift is installed to engine parts. The high stress element of frame supported petrolift. Consequently, it is desirable to install petrolift via the petrolift framework of high strength.

Described petrolift can also comprise the installation device for the framework of petrolift is connected to engine parts. This installation device is provided between framework and engine parts provides the approach firmly connected.

Described shell and installation device can comprise the complementary obstruction feature being arranged to and preventing installation device from rotating relative to shell separately. Such as, cover and installation device can comprise the complementary obstruction feature being arranged to and preventing installation device from rotating relative to cover separately. When petrolift is when operating, very big power is transmitted between drive unit and pump head. These parts applied forces cause the framework of petrolift to attempt motion in response to these power. Therefore, it is favourable for comprising complementary obstruction feature, and complementary obstruction feature is by the rotation stoping framework and install between device, thus contributes to firmly being held in place petrolift.

One in complementary obstruction feature can comprise projection, and another complementary obstruction feature can comprise depression. The obstruction feature of this kind of interlocking is at framework and installs the connection providing firm between device.

Described cover can comprise one or more unitary members, and the neglected loading of returning that this one or more unitary members can comprise the recirculation of auxiliary fluid is put. This one or more unitary members can comprise the fuel inlet that fuel is sent to petrolift. This one or more unitary members can comprise back neglected loading and put and fuel inlet. These parts are integrally formed provide in the enclosure less and be easier to manufacture petrolift.

Driving element can be formed by the multiple parts comprising shaft portion and cam portion. When using the framework formed by single-piece, this kind of layout is favourable. Cam portion can intensity be become by the material structure higher than shaft portion. This is because cam portion bears the major part of the load for making fuel pressure boost being delivered to pump head. This kind arranges the driving element providing manufacturing cost lower, this is because the sturdy material of costliness is only for needing the part of sturdy material.

Pump head can be contained in cover. It is included in cover by pump head to improve the cooling of pump head.

Embodiments of the invention provide the high pressure fuel pump lighter than pump weight known at present. The framework of high strength is set to the high stress portion (such as cam gear and pump head) by supporting pump and bears pumping load, and lightweight cover is set to seal described pump to prevent fuel leaks from pump.

Embodiments of the invention provide the high pressure fuel pump less than known fuel pump. This kind of embodiment adopts support frame and lightweight cover. This cover can relative thin, like this, due to only provide firm frame support instead of provide surround whole pump solid shell, because this reducing the total thickness of shell.

Embodiments of the invention decrease cost and the time of the new pump of prototype. Specifically, framework can be become by extruding metal, and can adopt and be injection molded into shell to construct cover. This kind of technology does not need to construct the slow and expensive supply needed for cast steel shell.

Accompanying drawing explanation

Describing embodiments of the invention now with reference to accompanying drawing by means of only way of example, wherein, identical Reference numeral is used for identical part, and in the accompanying drawings:

Fig. 1 diagram is according to the sectional view of the pump of the first embodiment of the present invention;

Fig. 2 provides the exploded view of the pump of Fig. 1;

The framework of the pump case of the pump of Fig. 3 pictorial image 1;

The cover of the pump of Fig. 4 pictorial image 1;

Fig. 5 provides the exploded view of the assembling device of the pump of Fig. 1;

Fig. 6 provides the exploded view of the assembling device of Fig. 5 from another viewpoint;

Fig. 7 provides Fig. 1 and 2 exploded view of illustrated cam gear; And

Fig. 8 provides the exploded view of substituting cam gear.

Embodiment

First should with reference to Fig. 1 and 2, it provides two substituting views of the pump 1 arranged according to a first embodiment of the present invention. First the operation that should relate generally to describe pump 1 is to describe this pump.

Low-pressure fuel enters pump 1 by the fuel inlet 2 in the cover 3 being integrated into pump 1. Then, fuel controls, through entrance metering valve (IMV) 4a of entrance metering valve (IMV) device 4 being installed on cover 3, entrance metering valve 4a, the flow rate that fuel enters pump 1. Cover 3 forms a part for pump case and limits inner chamber 5, and the pumping of pump 1 and drive element are disposed in inner chamber 5, and inner chamber 5 is filled with fuel. IMV device 4 is partially disposed between fuel inlet 2 and inner chamber 5; Therefore fuel from fuel inlet 2 through IMV4a and enters inner chamber 5.

Fuel in inner chamber 5 is used as the lubricant of the moving parts of petrolift 1, the parts to carry out cooling pump 1 by absorbing the heat of generation in pumping procedure and described fuel also works, thus takes away heat from the pumping parts of pump 1. In order to contribute to this process of cooling, it is provided that the neglected loading of returning of such as venturi arrangement puts 6, is sucked from inner chamber 5 to allow fuel and returns low pressure drain or engine cam case, so that fuel recycle. Therefore, return neglected loading and put the recirculation that 6 contribute to fuel, thus take away, from petrolift 1, the heat that pumping parts produce.

Pumping parts comprise pump head 7, the pumping element of plunger 8 form and drive unit, and this drive unit comprises slave 9 and drive shaft or cam gear 10. Pumping procedure occurs in pump head 7. Therefore, pump head is made up of firm material (such as hardened steel), so that the fuel under high pressure tolerating supercharging in the pumping chamber 7a of pump head 7 and the sizable power being applied on pump head 7 by pumping element 8 to make fuel pressure boost.

The pumping chamber 7a of pump head 7 is disposed in the end of the plunger hole 7b being arranged in pump head 7, and is the chamber of the fuel under high pressure outlet (not shown) comprising low-pressure inlet (not shown) for receiving fuel from the inner chamber 5 limited by cover 3 and outlet valve form. Pumping chamber 7a is partly limited by the pumping head at the first end place at plunger 8. Plunger 8 is arranged to to-and-fro movement so that the pumping head of plunger increases and reduces the volume of pumping chamber 7a. When the volume of pumping chamber reduces, the pressure increase of the fuel in pumping chamber 7a. When the fuel in pumping chamber 7a reaches predetermined pressure, outlet valve is opened to allow fuel under high pressure across and into high pressure rail (not shown), and at this place, fuel is stored to prepare to spray by one or more fuel injector (not shown).

At the 2nd end away from pumping chamber 7a of plunger 8, slave 9 be arranged to cooperate with cam gear 10 taking by the convert rotational motion of cam gear 10 as the to-and-fro movement of plunger 8 in plunger hole 7b.

The shaft portion 10a that cam gear 10 is provided with outside the cover 3 being positioned at pump 1 at least in part, engages with the driving source (not shown) with such as driving gear. The Input Forces that cam gear 10 provides in response to driving gear and rotate. The shaft portion 10a of cam gear 10 is also positioned partially in the inner chamber 5 of cover 3, and has the cam portion 10b in the part being positioned at inner chamber 5 being connected to axle 10a.

Slave 9 comprises roller bearing 9a, and roller bearing 9a and cam 10b is to connecing, so that roller bearing 9a couples with cam 10b with being connected. Roller bearing 9a is supporting in the rolling sleeve 9b that the 2nd end with plunger 8 is connected. When cam 10b rotates, roller bearing 9a rotates in rolling sleeve 9b. The layout limit lateral movement of roller bearing 9a and rolling sleeve 9b is delivered to plunger 8 from cam 10b, the to-and-fro movement of cam 10b is delivered to plunger 8 simultaneously. Spring 11 is held in place between pump head 7 and the spring support 8a being installed on plunger 8, to promote (urge) plunger 8 and connected rolling sleeve 9b to become to contact with cam 10b. Due to spring 11, slave 9 continues to follow the to-and-fro movement of cam 10b.

Slave 9 also comprises cover guide member 9c, around its outer surface being arranged on rolling sleeve 9b, so that the motion of guide rollers cover 9b. Therefore, guide member 9c makes rolling sleeve 9b can move along the axis of plunger 8, thus allows the to-and-fro movement overlapping guide member 9c still to limit its transverse movement. Cam gear 10 be rotated on slave 9 to apply transverse force, and thus overlap guide member 9c and be made up of firm material, so that it is laterally mobile and tolerate the stress relevant to this kind of resistibility to resist this kind.

Such as, although above-mentioned slave 9 being described as the device based on roller bearing, it should be understood that any suitable slave (tappet or other midway drive parts) can be used.

Except cover 3, pump case also comprises framework 12. Framework 12 is set to support various pumping and drive element, specifically stands the pumping parts 7,9,10 of high stress level because of pumping procedure. Thus, framework 12 is arranged to the axle 10a supporting pump head 7, rolling sleeve 9 and cam gear 10. Therefore, framework 12 is made up of relatively firm material (such as aluminium), to tolerate the high stress level in pump 1, this high stress level is specifically caused by the power being delivered to plunger 8 from cam gear 10, being then delivered in the fuel in pump head 7.

In order to the rotation of auxiliary cam device 10 and prevent overload and the abrasion of framework 12, at the some parts place of the supporting cam wheel device 10 of framework 12, lining 13a, 13b are set.

As seen in Figure 2, installing device 14 and be provided with the mounting plate 14a in cover 3 outside, pump 1 is connected to engine by described mounting plate. Install device 14 be connected to framework 12 by cover 3 so that for framework 12 and therefore firmly support for pump 1 provides. Owing to framework 12 and installation device 14 are by cover 3 connection, therefore device 14 are installed and comprise multiple sealing member 14b, 14c, in case fuel passes through cover 3 leakage.

Each parts of pump 1 are discussed in more detail now with reference to each accompanying drawing.

The structure of framework 12 should be discussed with further reference to Fig. 3, and Fig. 3 illustrates the framework 12 of the pump of the first embodiment of the present invention.

Framework 12 is provided with two cam support part 12a, 12b, each cam support part limiting hole 12c, 12d, by described hole 12c, 12d can supporting cam wheel device 10(illustrate in fig 1 and 2), wherein, cam 10b is between two cam support part 12a, 12b. The outside surface that hole 12c, the 12d limited by cam support part 12a, 12b respectively is shaped to the axle 10a with cam gear 10 is complementary. Thus, in this case, hole 12c, 12d are circular, complementary with the cylindrical shape with the axle 10a of cam gear 10. Like this, cam gear 10 can steadily rotate. The size of framework 12 is arranged such that lining one of 13a, 13b can be placed in hole 12c, the 12d limited by each cam support part 12a, 12b, to contribute to the rotation of the axle 10a of cam gear 10. Fuel in the inner chamber 5 limited by the inwall of cover 3 contributes to lubrication framework 12 and lining 13a, 13b, so that the steady rotation of the axle 10a of auxiliary cam device 10 minimum wear. Cam support part 12a, 12b bear most of weight and the stress of cam gear 10. But, the part that device 14 bears the load being applied on the cam support part 12a adjacent with installing device 14 is installed.

Framework 12 is also provided with pump head support section 12e. This part 12e has the hole 12f for holding pump head 7. Specifically, the front surface of pump head 7 protrudes through this hole 12f at least in part. The front surface of pump head 7 comprises the depression partly limiting pumping chamber 7a, and the pumping head of plunger 8 inserts in this depression, thus limits pumping chamber 7a.

Multiple screw hole 12g(only illustrates one in figure 3) it is arranged in the pump head support section 12e of framework 12, by described screw hole, pump head 7 can be connected to framework 12 by screw (not shown). Pump head 7 firmly must be clamped to framework 12, drive in pump head 7 with box lunch plunger 8 thus provide and prevent pump head 7 to be separated with framework 12 during the power promoted away from framework 12 by pump head 7. Alternatively, framework 12 can be arranged to provides at least one bracing member (not shown), and the rear surface of described bracing member and pump head is to connecing thus does not rely on coupling screw and is remained on framework 12 by pump head 7.

Framework 12 is also provided with cover guide member support section 12h(and only illustrates one), it comprises multiple pillar (not shown) of support set guide member 9c.

Cam support part 12a, 12b, pump head support section 12e and cover guide member support section 12h are bonded together by the main structure of framework 12. These part 12a, between 12b, 12e, 12h, especially Structure of need rigidity between cam support part 12a, 12b and pump head support section 12e, enter what the relative movement of pump head 7 realized this is because the supercharging of fuel is the plunger 8 by driving by cam gear 10. Thus, pump head 7 needs relative to the position of cam gear 10 to keep constant, to allow pump 1 correctly to operate.

Hole or breach 12i can be arranged in the main body of framework 12, to reduce the weight of framework 12 when not reducing the relative intensity of framework 12, so that framework 12 firmly can support for the parts standing high stress level of pump provide.

Should be appreciated that, although coming supporting cam wheel support section 12a, 12b, pump head support section 12e and cover guide member support section 12h by the main body of framework 12 in the present embodiment of the present invention, but alternatively, shore supports part can be set between each part of framework 12, described part to be linked together. Use shore supports part can help the weight reducing framework 12 further between multiple parts of framework 12, and the size of framework 12 can be reduced in some arrangements.

In the present example, framework 12 is also provided with attachment hole 12j, 12k, 12l, 12m, is connected to install device 14 by pump 1 for via framework 12. When describe in detail with reference to Fig. 5 and 6 device 14 is installed time, it should hole 12j, 12k, 12l, 12m and their relations with installation device 14 are discussed.

Framework 12 is made by extruded aluminium bar. The execution of extrusion process is quick and cheap. By forming framework 12 via extrusion process, framework 12 can be formed as parts. In other words, framework 12 is become by wall scroll extruding metal, and there thus do not have part to need to be engaged. Contrastingly, casting technique needs two or more parts to be cast, and is joined together after these parts. There is the risk of the joint formation structure reduction at these parts. Thus, extrusion process overcomes these problems.

In addition, owing to squeezing out framework 12, the cutting of framework and the amount of drilling is therefore minimized. Specifically, extrusion process allows some feature forming framework 12 during extrusion process in framework 12, such as hole. Contrastingly, foundry engieering needs to add all features after the casting, therefore causes further structure to weaken.

Although it is to be understood that it is made of aluminum to describe framework 12, but any suitable firm material can be adopted. Specifically, it is possible to use any suitable metal or other material, e.g., composite plastic or the composite plastic being encapsulated in sintering metal. It may be noted that while it is preferred that use extrusion process carrys out tectonic framework 12, but other construction process such as cast can also be adopted.

The cover 3 limiting inner chamber 5 is arranged to and surrounds pumping and the drive element that framework 12 and framework 12 support. In other words, pumping and drive element are disposed in the inner chamber that framework 12 limits at least in part. Therefore, cover 3 provides the anti-fluid leak shell around pumping parts, so that fuel can not leak from inner chamber.

Although figure 1 illustrates all pumpings and drive element that cover 3 surrounds pump 1, it should be understood that cover 3 is arranged to the inner chamber limiting contain fuel, for the object of Cooling and Lubricator. Such as, therefore, the driving of the motion of pump 1 and pumping part (plunger 8, slave 9 and cam gear 10) need this kind of lubrication and cooling. Thus, it should be appreciated that do not need to be enclosed in cover 3 whole pump head 7. Can providing such cover, this cover engages the outer surface of pump head 7 or the front surface of pump head 7. In this case, the front surface of pump head 7 can be connected with the fuel fluid in inner chamber 5, and the sidepiece of pump head 7 can be positioned at cover 3 with whole rear portion at least partially outside. It may be noted that due to the constant fuel stream flowing through pump head, the heat thus produced in pump is taken away by pressurized fuel at least in part, therefore carry out pump head cooling not as cooling important like that to the moving parts of pumping procedure.

As shown in Figure 2, cover 3 to be formed by two part 3a, 3b. Part 3a, 3b are arranged to around the parts assembling being attached to framework 12 and be in framework 12. Then, two part 3a, 3b of plastic lousing can be joined together, so that fluid is sealed within it by two-part cover 3. Can by any method of the combination of anti-fluid leak can be provided to engage described two parts.

Fig. 4 illustrates a half portion 3a of cover 3. Visible in the diagram, cover 3 has multiple inner support pillar 3s. Supporting strut 3s reinforces cover 3, to improve the intensity of cover 3. Thus, it is possible to there is thinner cover 3, enough intensity is still provided the while of. Pillar 3s can also be set to the outside surface with framework 12 to connecing, so that cover 3 firmly is formed around framework 12.

In the present embodiment of the present invention, framework 12 only joins cover 3 to via installation device 14. However, it should be understood that cover 3 can be connected to framework 12 by various mode (the one or more coupling screws such as having and preventing, by adopting, the appropriate seal leaked from cover 3).

Injection molding technology is utilized to form two cover part 3a, 3b by plastics. Thus, hight frequency welding can provide the appropriate combination between two part 3a, 3b. But, other material of such as metal can also be used for cover 3. Such as, it is provided that the framework 12 of aluminium and cover 3. Owing to cover 3 only needs to provide anti-fluid leak, therefore described cover can be formed as much thinner than framework 12. In addition, due to the relative intensity of metal compared with plastics, metal cover 3 can be formed as much thinner than plastic lousing 3. Due to its conductivity, metal cover 3 also can contribute to walking heat from the fuel tape in inner chamber.

Although the inner chamber 5 limited by cover 3 in the present embodiment of the present invention of reference Fig. 1 and 2 discussion is filled with fuel, it should be understood that can provide other fluid in inner chamber 5. Such as, inner chamber can comprise specific cooling/lubricating fluid. In this case, IMV device 4 directly or via accommodation passage can be connected to pump head 7 from fuel inlet 2. In this arrangement, it is possible to cooling fluid inlet (not shown) is set, and return neglected loading and put 6 and will contribute to making cooling fluid recirculation.

Except limiting inner chamber 5, cover 3 also limits the various features of petrolift 1, described in as follows.

Cover 3 comprises IMV connection portion 3b, and it is arranged such that the shell of IMV device 4 can be connected to pump 1. IMV connection portion 3b limiting hole 3c, a part for IMV device 4 can be arranged in this hole 3c, so that IMV4a can be connected to fuel inlet 2. One or more connection hole 3d can be set in cover 3, so that IMV device 4 can be attached on cover, so that IMV device 4 is maintained on pump 1 in place.

Cover 3 also provides time neglected loading being integrally formed to put 6 and the fuel inlet 2 being integrally formed. When utilize injection molding forming method by plastics to construct cover 3 time, it is favourable for being integrated in cover 3 by these parts, this is because described parts are formed as a part for cover 3 in molding process. In addition, it is integrated in cover 3 by these parts to simplify the whole manufacturing processed of petrolift 1 and reduces the size of petrolift 1.

The shell comprising framework 12 and cover 3 is far smaller than known shell. This is because, framework 12 can provide required minimum support structure, and relative thin and light cover 3 can be provided to provide the sealing of anti-fluid leak for pump 1. In a word, this can reduce shell overall size and therefore reduce pump 1 overall size. In addition, it is possible to select the material being used for framework 12 and cover 3, to mate its corresponding function best, this can reduce the weight of shell and the weight of therefore reduction pump 1.

Another advantage of this kind of suprastructure is, with adopt cast steel shell petrolift situation compared with, it is possible to IMV device 4 is placed more near pump head many. This is because, framework 12 can only be arranged in those parts needing support, and cover 3 and can be arranged to closely around this framework 12 so that IMV device 4 can be placed as near pump head 7. Like this, it is possible to reduce whole pump head 7 further.

Although being disposed in cover 3 being hereinbefore described framework 12, it should be understood that framework 12 can be set to make it only be positioned partially in cover 3. Such as, outside the main structure of framework 12 can be arranged on cover 3, wherein sway brace extends through cover 3 to support the high stress element of pump 1. In this case, device 14 is installed and can easily be connected on framework 12, be even integrally formed with framework 12.

Now with reference to Fig. 5 and 6, the installation device 14 shown in Fig. 2 is described more in detail.

Installing device 14 and comprise mounting plate 14a, it is arranged to the parts being connected to engine, with fixing and stable pump 1. Mounting plate 14 is substantitally planar structure, and it has multiple hole or otch to reduce the weight of plate 14a. Mounting plate 14a is provided with multiple screw hole 14d, 14e, 14f for screw (not shown), so that mounting plate is connected to engine. Other screw holes 14g, 14h, 14i, 14j are set, to allow mounting plate 14 by being connected by the screw in the hole in cover 3 and to be connected to framework 12. Thus, a surface of mounting plate 14a is arranged on cover 3 and settles (sitflush) stablely, and is connected to framework 12 by cover 3, so that cover 3 is maintained between mounting plate 14a and framework 12.

Owing to for mounting plate 14a being connected to the screw of framework 12 through cover 3, installing device tightness system it is thus desirable to provide. By providing, the first sealing member 14b and the 2nd sealing member 14c realizes for this, and described sealing member seals the gap on the outside surface of the gap between mounting plate 14a and cover 3 and mounting plate 14a respectively.

First sealing member 14b is in the form of the packing ring between mounting plate 14a and cover 3. Packing ring 14b is arranged to and makes it around all screw holes in cover 3 and those screw holes 14g, 14h, 14i, 14j in mounting plate 14a, thus forms the inner chamber being used for fluid between mounting plate 14a and cover 3. Owing to framework 12 and mounting plate 14a are clamped together by screw, therefore packing ring 14b is clamped between mounting plate 14a and cover 3. Therefore, packing ring 14b provides the sealing of anti-fluid leak between cover 3 and mounting plate 14a. Alternatively, the first sealing member can be provided by multiple packing ring, and each packing ring is set up around single screw hole.

2nd sealing member 14c is the form of RUBBER O shape packing ring, and is disposed on the outside surface of mounting plate 14a. O shape packing ring 14c prevents fuel from leaking from the head of the screw through mounting plate 14a.

In order to stop shell to rotate relative to mounting plate 14a, cover 3 is provided with multiple projection 3m, and multiple projection 3m is set to engage with the multiple complimentary recess 14k in mounting plate 14a. In use, this kind of cover 3 and mounting plate 14a is bonded to and helps stop mounting plate 14a to rotate relative to cover 3. Thus, the obstruction of this feature offer along the radial direction of the axle 10a of cam gear 10 of device 14 is installed, rotates to contribute to preventing installing device 14.

It is to be understood that other projections that the radial obstruction feature being arranged between cover 3 and mounting plate 14a can be included in framework 12, in the rear portion of its projection 3m being projected in cover 3. Thus, framework 12 is by supporting projections 3m and thus for the relative rotation between shell and mounting plate 14 provides addedresistance.

Mounting plate 14a can be squeezed into by aluminium bar. This kind of manufacturing process is cheap and quick. But, it is possible to use any suitable material or manufacturing process.

The structure of the cam gear 10 shown in Fig. 1 and 2 is considered in detail referring now to Fig. 7.

Generally speaking, it is known that drive shaft be configured to by single metal part, and by two-part cast steel shell support, this shell is constructed around drive shaft. But, when using together with extruded aluminium framework or any stationary frame structure, standard drive shaft can not be used.

In the embodiments of the invention shown in Fig. 1 and 2, it is provided that multiple piece cam gear 10. Cam gear 10 comprises three parts: axle 10a, cam 10b and rear bearing axle journal 10c. Axle 10a extends along the length of cam gear 10, and cam 10b and rear bearing axle journal 10c is installed on axle 10a, so that cam gear 10 can be built in fixing framework 12.

Axle 10a is the slim-lined construction with stepped cylindrical shape, and it has multiple cylindrical part, and the diameter of described cylindrical part reduces towards one end of axle 10a. Axle have the first reduced diameter portion being press-fitted on cam 10b on it divide 10aa and axle 10a end its on be press-fitted on rear bearing axle journal 10c adjacent Second bobbin diameter reduce part 10ab. Second bobbin diameter reduces part 10ab and has the diameter dividing 10aa little than the first reduced diameter portion.

In order to be assembled in framework 12 by cam gear 10, first need the gap being inserted through in Fig. 3 by cam 10b between two cam support part 12a, 12b. Then, axle 10a is inserted through framework 12 the first cam support part 12a, through cam 10b and insert in rear bearing axle journal 10c, rear bearing axle journal 10c is arranged to and is supported in the 2nd cam support part 12b of framework 12 by axle 10a.

Fig. 8 illustrates substituting cam gear 100, and it adopts key interference to engage. In the present embodiment of the present invention, cam gear 100 comprises axle 100a, cam 100b, rear bearing axle journal and two joints element (or key) 100d, 100e. Axle 100a and cam 100b is provided with and the depression part 100aa engaging element 100d, 100e joint, 100ba, 100bb(or keyway). Therefore, engage element 100d, 100e as providing the middle interconnecting piece of junction surface or bridge to divide between axle 100a and cam 100b, to contribute to the part preventing cam gear 100 to be relative to each other moved into dislocation. Therefore, the device 100 of Fig. 8 provides drive shaft device 100, and it is firmer than the said apparatus 10 of the press-fit depending on parts.

Should be appreciated that, although having described press-fit and key elastic conjunction device, but can be connected the part of cam gear by any suitable means, described means are such as connected interference (serialinterference), thermal expansion interference, spline interference, or hydraulic pressure is shaping.

Construct cam gear 10,100 from multiple part and make can more cheaply construct cam gear compared with the drive shaft being made up of single-piece. Specifically, cam 10b, 100b can be made up of high tensile steel, because high tensile steel absorbs major part stress, and axle and rear bearing axle journal can be made up of the steel of relatively inexpensive grade.

The cam gear 10 of illustrated embodiment is used as the driving element of pump, for motivating force is delivered to pumping element so that fuel pressure boost in pump head. It is to be understood that other driving element can be contemplated.

Such as, although this document describes and using fixing framework 12 and the cam gear 10 being made up of multiple part, it should be understood that in some cases, it is possible to preferably adopt the driving element comprising single-piece drive shaft and the framework being made up of multiple part.

Having utilized the present invention of linear pumping unit describe, wherein, cam 10b, 100b drive elongated plunger 8 to be driven in pumping chamber 7a. However, it should be understood that the pumping installation of replacement can be used. Such as, it is possible to adopt the driving element comprising rocker-arm pumping arm. In this case, it is possible to supported the drive member of rocker arrangement in the way of similar with the cam gear shown in Fig. 1 by framework.

Describe the above embodiment of the present invention with reference to the single pump 1 with single pump head 7 and single cam gear 10. However, it should be understood that the principle of the present invention can be applied to the pumping system comprising multiple pump head and one or more drive shaft equally.

When not departing from the scope of the present invention being defined by the following claims, other remodeling and amendment it will be apparent to those skilled in the art that. Although for example, it should be understood that described embodiment relates to fuel lubricated formula petrolift, but the present invention can be applied to oil lubricating type pump equally.

Claims (15)

1. one kind for making the petrolift (1) of the fuel pressure boost in high pressure fuel injection system, and described petrolift (1) comprising:

Pump head (7), described pump head has the pumping chamber (7a) being arranged to and receiving the fuel treating supercharging;

Pumping element (8), described pumping element is arranged to the motion in response to driving element (10) and to-and-fro movement, described pumping element (8) partly limits described pumping chamber (7a), make in use when described pumping element (8) to-and-fro movement, the power transmitted from described driving element (10) is applied to the fuel in described pumping chamber (7a), so that described fuel pressure boost;

Framework (12), described framework is arranged to and supports described driving element (10) and described pump head (7); And

Cover (3), described cover is defined for the internal space (5) holding fluid;

Wherein, described framework (12) at least partially, described driving element (10) at least partially and being accommodated at least partially in described cover (3) of described pumping element (8).

2. petrolift according to claim 1 (1), wherein, described framework (12) is arranged to and described pump head (7) and described driving element (10) is remained in fixed position relative to each other, with anchorage force from described driving element (10) to the transmission of described pump head (7).

3. petrolift according to claim 1 and 2 (1), wherein, described framework (12) constructs the high material structure of the material of described cover (3) by strength ratio and becomes.

4. petrolift according to claim 1 and 2 (1), wherein, described framework (12) is formed by single-piece.

5. petrolift according to claim 4 (1), wherein, described framework (12) is formed by single-piece by extrusion process.

6. petrolift according to claim 1 and 2 (1), wherein, described cover (3) is formed by the material based on plastics.

7. petrolift according to claim 1 and 2 (1), wherein, described framework (12) is arranged to be installed on engine parts described petrolift (1).

8. petrolift according to claim 7 (1), also comprises:

Device (14) is installed, is connected to described engine parts for by the described framework (12) of described petrolift (1).

9. petrolift according to claim 8 (1), wherein, each obstruction feature (3m, 14k) including the complementation being arranged to stop described installation device (14) to rotate relative to described cover (3) of described cover (3) and described installation device (14).

10. petrolift according to claim 9 (1), wherein, the one in the obstruction feature of described complementation comprises projection (3m), and the obstruction feature of another complementation comprises depression (14k).

11. petrolifts according to claim 1 and 2 (1), wherein, described cover (3) comprises one or more unitary members (2,6), described parts comprise the recirculation of auxiliary fluid return that neglected loading puts (6) and be sent to by fuel in the fuel inlet (2) of described petrolift (1) one or more.

12. petrolifts according to claim 1 and 2 (1), wherein, described driving element (10) is formed by the multiple parts comprising shaft portion (10a) and cam portion (10b).

13. petrolifts according to claim 12 (1), wherein, described cam portion (10b) is become by the material structure that shaft portion described in strength ratio (10a) is high.

14. petrolifts according to claim 1 and 2 (1), wherein, described pump head (7) is accommodated in described cover (3).

15. petrolifts according to claim 1 and 2 (1), wherein, described framework comprises at least one bearing (12c, 12d, 13a, 13b), and described bearing (12c, 12d, 13a, 13b) is arranged to the described driving element of support (10) and is rotated for relative to bearing (12c, 12d, 13a, 13b).