EP1051566B1 - Butterfly valve body - Google Patents

Description

The invention relates to a throttle valve assembly with a throttle valve housing made of plastic according to the features of the preamble of Claim 1.

Throttle body of throttle body are usually made of die-cast aluminum. However, this has the Disadvantage that an elaborate and careful post-processing is required is, with the fact that such a throttle body are heavy and have poor corrosion resistance.

Therefore, it has already been considered to remove the throttle body Manufacture plastic by injection molding. Such throttle body made of plastic have the advantage that they are lighter in weight have compared to aluminum housings that the manufacturing material is cheaper and also that in the molded during the injection molding process Openings inserts, for example for storage, are pressed can, so that postprocessing is no longer necessary at all is or can be significantly minimized.

However, throttle body made of plastic have the Disadvantage on that during and after the injection molding process can shrink and warp after removal from the mold. The same applies to the effects of temperature and force, especially since such throttle valve bodies are arranged in the engine compartment of vehicles, where they are very large Are subject to temperature fluctuations. For example, is the drive motor of the vehicle is not in operation and there is little Outside temperature, very low temperatures are reached (for example around freezing or even below); on the other hand, at Operation of the internal combustion engine a very high temperature (in particular reached over 100 ° C). Therefore, it comes especially because of this strong temperature fluctuations to disadvantageous deformations in the swivel area the throttle valve, so that the high leakage air requirements, especially in the idle position of the throttle valve and around these around, cannot be met. This is precisely the area but especially important as it has a huge impact on fuel consumption and also affects the exhaust gas quality. Therefore it is special it is important that the intake wall of the throttle valve connector at the conditions mentioned as well over a long time, in particular maintains its dimensional accuracy for several years.

Therefore, it has already been proposed in DE 43 34 180 A1 that in the throttle body made of plastic is an annular Insert part is embedded transversely to the intake duct, this insert part has angled tabs through which the throttle valve shaft protrudes and the tabs each with a tab surface facing away from the throttle valve on one of the throttle valve end faces of the Storage facilities. First of all, this ring-shaped insert has due to its geometric design, the disadvantage that it is expensive in the production, especially in a series production of Throttle body, is.

The main disadvantage, however, is that the annular insert after the injection molding process is completely surrounded by plastic, so that the throttle valve is again a large area in its swivel range plastic inner contour of the intake wall. Due to the high requirements with regard to environmental protection (exhaust gas quality) and fuel consumption is still required Dimensional accuracy, even if it has already been improved somewhat, not given, so that the plastic Deform suction wall despite ring-shaped insert, pull together or can expand, so that the high Leakage air requirements are still not met.

It is also known from FR-A-2 762 374, in the amount of Storage of the throttle valve to arrange an insert. This Insert can for example be made of metal and has at least one on its outer and / or inner wall cylindrical section. This ring-shaped insert is also very good because of its geometric design costly to manufacture. Furthermore, more Elements of the throttle body in which the insert surrounding plastic can be attached. This also means this throttle body the necessary dimensional accuracy of Components not given to each other.

The invention is therefore based on the object Throttle body further improve, so that the posed Requirements regarding the exhaust gas quality of the Fuel consumption, but also in terms of an even response of the internal combustion engine to accelerating, be fulfilled. The advantages of a plastic throttle body are said to be not be abandoned.

This object is due to the features of claim 1 solved.

According to the invention it is provided that at least in a partial swivel range a metal cylinder in the throttle valve Line section is provided.

Due to the stability of a metal cylinder, the throttle valve at least in the relevant partial swivel range always a precisely defined and dimensionally stable inner wall is presented, which changes even with temperature fluctuations and over for a long period of time or in negligible Changed way so that the required dimensional accuracy given is. The metal cylinder can be in the injection mold be inserted and then extrusion-coated with plastic that its inner wall remains free, so that the Throttle valve is presented with a metallic surface. alternative it is also possible to first the throttle body made of plastic and then the metal cylinder use. The metal cylinder is also conceivable to manufacture from several parts, for example two Halves in the plane in which the throttle valve shaft is located, can collide. You could also think the inner wall of the metal cylinder with a thin Protective layer (for example made of the same plastic) which also contains the throttle valve housing) whose thicknesses have no influence on the dimensional accuracy. A such protective layer effectively prevents the deposition of disruptive particles on the inner wall. Furthermore, the Metal cylinder also for holding further elements of the throttle valve body such as for holding a throttle potentiometer or a drive motor. Other elements of the throttle valve assembly can also Shafts for a gearbox over which the throttle valve shaft from is driven by an electric motor. Holes can also be used be provided in the metal cylinder on which the other elements, such as a carrier plate of the Throttle potentiometer, after the manufacture of the throttle body be screwed on. The metal cylinder can also Stops, for example for a final position of the Have throttle valve or the throttle valve.

In a further development of the invention, the metal cylinder is in Flow direction below and / or above the throttle valve supporting throttle valve shaft provided. Just that Area around the plane in which the throttle valve shaft is arranged is particularly important as this is the area acts in which the idle speed with the throttle valve is set. Therefore, it is particularly in this area good dimensional accuracy is required with the metal cylinder is achieved. In addition, the metal cylinder but also over a larger swiveling range Throttle valve and possibly extend beyond.

In a development of the invention, the metal cylinder is Recording designed for the throttle shaft bearings. A further increased strength is thereby achieved the manufacturing process is also simplified. It can First the metal cylinder is made, which then with the bearings for the throttle valve and then is encapsulated with plastic. Another advantage is in it to see that in the same shape and the throttle body different metal cylinders (especially with different ones Longitudinal extension and / or different Diameter) can be used, whereby the variety of parts, in particular the number of shapes for the throttle body, can be reduced.

In a development of the invention, the metal cylinder has a Inner contour to achieve a specifiable characteristic for the Volume throughput depending on the pivoting of the Throttle valve open. By manufacturing a corresponding metal cylinder, for example made of die-cast aluminum or magnesium, (including other materials and manufacturing processes are possible) and one that may become necessary Finishing is through the inner contour of the metal cylinder a characteristic curve for the volume flow through the Line section achievable, which depends on the Swiveling of the throttle valve adjusts. Thus, for Example of an inner contour cause that in the closed position the throttle valve has no or almost no volume throughput through the line section. The one end position which was previously referred to as the closed position, must Do not necessarily completely close the line section, but it can be with this End position also act as a minimum position at which a defined Leakage air flows through the line section. With increasing pivoting the throttle from the closed position respectively The minimum throughput takes the volume throughput as a function of inner contour used further until another end position, in particular represents a complete opening of the line section, is achieved.

In summary it can be said that the advantages of the invention a plastic throttle body (like low weight and low material costs), but the one Throttle body made of plastic disadvantages as not sufficient dimensional accuracy is eliminated by using the metal cylinder be so that the desired characteristic even with temperature fluctuations and securely adjustable over a long period (several years) is and will be maintained.

The throttle valve assembly according to the invention can be a act so-called coupled system, in which the throttle valve about connecting elements such as Bowden cables or the like with a Accelerator pedal is connected to the power request. It is the same with such Systems conceivable, in addition in some areas (especially in Idle range) via an actuator (especially an electric motor) superimposed control (especially idle control). The throttle body is also found in so-called drive-bywire systems Application where the performance requirement (for Example of operating an accelerator pedal) converted into electrical signals is, the signals are fed to a control unit, which in turn controls an actuator which then at least in the throttle valve Dependence of the performance requirement and, if necessary, further parameters established.

The present invention is based on the example of a throttle valve assembly explained, this field of application is regarded as preferred; however, the present invention is not based on this embodiment limited, but can also in a corresponding manner, if necessary under first name minor modifications, in other areas of application be used.

Figur 1:

einen Drosselklappenstutzen in dreidimensionaler Schnittdarstellung,

Figur 2:

den Drosselklappenstutzen gemäß Figur 1 im Querschnitt mit abgenommenem Deckel,

Figur 3:

den Drosselklappenstutzen gemäß Figur 1 im Querschnitt mit aufgesetztem Deckel,

Figur 4:

den Drosselklappenstutzen im Längsschnitt gemäß Figur 1,

Figur 5:

den Drosselklappenstutzen gemäß Figur 1 in geschnittener, dreidimensionaler Ansicht,

Figur 6:

den Drosselklappenstutzen im Schnitt in einer abgewandelten Ausführung gegenüber Figur 1,

Figur 7:

den Drosselklappenstutzen im Längsschnitt gemäß Figur 1, mit einem Metallzylinder mit Innenkontur.

Show it:

Figure 1:

a throttle valve connector in a three-dimensional sectional view,

Figure 2:

the cross-section of the throttle valve according to FIG. 1 with the cover removed,

Figure 3:

the cross-section of the throttle valve according to FIG. 1 with the cover attached,

Figure 4:

the throttle valve neck in longitudinal section according to Figure 1,

Figure 5:

1 in a cut, three-dimensional view,

Figure 6:

the throttle body in section in a modified version compared to Figure 1,

Figure 7:

the throttle body in longitudinal section according to Figure 1, with a metal cylinder with an inner contour.

Figure 1 shows a throttle valve 1 in a three-dimensional sectional view. Such throttle body are used for the injection device an internal combustion engine, in particular for a vehicle, air or supply a fuel-air mixture. For this purpose the Throttle body 1 a throttle body 2 on that Plastic, especially in an injection molding process, is produced. In this throttle valve housing 2 there is a line section 3, the air or the injection device, not shown the fuel-air mixture is supplied. For setting the to be fed Volume is on a throttle valve shaft 4, a throttle valve 5 arranged, the rotation of the throttle valve shaft 4 also Throttle valve 5 is pivoted and the cross section in the line section 3 more or less enlarged or reduced and thus regulates the volume throughput.

In a simple embodiment of the throttle body 1 is one end the throttle valve shaft 4, for example, connected to a rope pulley, this pulley in turn via a Bowden cable with an adjusting device for a performance request, the Adjustment device is, for example, the accelerator pedal of a vehicle, so that by operating this adjustment device by the driver The throttle valve 5 from a position of minimal opening, in particular a closed position, up to a position of maximum opening can be brought to the power output of the internal combustion engine to be able to adjust.

The throttle valve connector 1 shown in FIG. 1 is such a throttle body, in which the throttle valve 5 either in a partial area, for example the idle area, by one Actuator, otherwise via the accelerator pedal, is adjustable or at which the throttle valve 5 over the entire adjustment range by an actuator is adjustable. With these so-called "E-Gas" or "Drive-bywire" systems the performance requirement is, for example, by depressing of the accelerator pedal converted into an electrical signal, wherein this signal is fed to a control unit, which is then a control signal generated for the actuator. That is, with these systems mentioned there is no mechanical connection between the setpoint specification (Accelerator pedal) and the throttle valve 5.

Therefore, the throttle body 2 of the throttle body 1 a gear housing 6 and a drive housing 7, wherein in preferred Embodiment, the throttle valve housing 2, the transmission housing 6 and the drive housing 7 form an integral unit and be produced in the same manufacturing process. It is also conceivable such an arrangement in which individual housings are assembled can be. In the drive housing 7 is designed as an actuator Electric motor (not shown in Figure 1) housed the one Reduction gear (also not shown in Figure 1) on the throttle valve shaft 4 acts, so that by driving the electric motor Throttle valve 5 is pivoted. The control of the electric motor takes place via a plug 8 arranged in the gear housing 6, wherein the throttle valve connector 1 via the connector 8 with a control unit connected is. A feedback is also provided via the connector 8 the respective position of the throttle valve 5 to the control unit, wherein this control unit by comparing the target value (accelerator pedal) with the Actual value for the position of the throttle valve 5 controls the electric motor until the difference between the setpoint and actual value is zero. The actual position the throttle valve 5 can, in particular, by a corresponding sensor a so-called throttle valve potentiometer, in which the Wiper of the potentiometer is connected to the throttle valve shaft 4, be recorded.

The gear housing 6 including the drive housing 7 is from closed a housing cover 9. The design and assembly of the housing cover 9 is described in more detail in Figures 2 and 3.

The throttle body 1 is usually in a suction system Internal combustion engine is arranged and assembled as a module, for which the in Figure 1 shown throttle body 1 has a flange 10 with which he has a suction line, not shown, with an intake air filter can be connected or connected directly to this intake air filter is. For fastening the throttle valve connector 1 to the injection device with the side facing away from the flange 10 are bores 11 provided with which the throttle valve body 1 sealing to the injector can be screwed on. The type of attachment is only by way of example and not essential to the invention.

Furthermore, the three-dimensional sectional view of the throttle valve assembly 1 a dashed metal cylinder 12 in the line section 3 arranged. The outer peripheral surface of the metal cylinder 12 is completely made of the plastic of the throttle valve housing 2 surround, the metal inner wall of the metal cylinder itself over the pivoting range of the throttle valve 5, possibly something less or a little more than this pivoting range. Various Embodiments of the metal cylinder 12 are in the following Figures recognizable.

Figure 2 shows the throttle valve 1 according to Figure 1 in section removed housing cover 9. Very good in this cross section Location of the metal cylinder 12 recognizable, the one piece in simple form Is tube that has bushings 13 for the throttle valve shaft 4. The inner wall of the metal cylinder 12 can be machined with a contour, by predetermined characteristics for the volume throughput through the line section 3 depending on the position of the throttle valve 5 to be able to. FIG. 2 shows an embodiment of the metal cylinder 12 shown, in which the metal cylinder 12 in the region of the bushings 13 each has an extension 14, these extensions 14 bearings 15, 19th for throttle valve shaft 4. This increases the ease of installation, since after the overmolding of the metal cylinder 12 with Plastic for molding the entire throttle body 2 also the bearings for the throttle valve shaft 4 are already available. The Throttle valve shaft 4 ends - when viewing FIG. 2 on the left Side - in a room 16, in which, for example, so-called return springs and emergency springs can be accommodated. The return spring causes the throttle valve shaft 4 to be preloaded in the closing direction, so that the actuator works against the force of this return spring. A so-called emergency running spring causes that in the event of actuator failure Throttle valve 5 is brought into a defined position, which is usually is slightly above the idle speed. Alternatively or in addition can also the throttle valve shaft 4 beyond the space 16 from the Throttle body 2 protrude, then at this end Throttle valve shaft 4, for example, a pulley is mounted, the is connected to an accelerator pedal via a Bowden cable, with which a mechanical setpoint is implemented. That facing away from room 16 End of the extension 14 (the end face) of which can be received other elements such as the attachment of a carrier plate of the throttle valve potentiometer can be used. Likewise, the End face of this extension 14 or further extensions, the end faces protrude into the gear housing 6 to accommodate further elements, such as stub shafts for gears or tooth segments of the not shown transmission, are used.

The throttle valve housing 2 also points in the direction of the housing cover 9 shows a circumferential flattening 17 with a circumferential web of the housing cover 9 corresponds. So far it was so that the housing cover 9 by screwing or by means of clip connections with the interposition of a seal with the throttle body 2 was connected. This meant a lot of effort there in the manufacture of the mold for the throttle body 2 and the housing cover 9 corresponding training can be provided had. In addition, the presence of the seal meant another Component and associated the insertion of the seal another Installation step, which is currently happening in the series production of throttle body turned out to be disadvantageous. Due to the all-round flattening 17 on the throttle valve housing 2 and the circumferential web 18 on the housing cover 9 (or vice versa) already during manufacture for the shape of the throttle body 2 and the housing cover 9 can be provided from plastic, is first achieved that after putting on the housing cover 9 a defined Position on the throttle body 2, if necessary under a slight Game is achieved.

Figure 3 shows the throttle valve assembly 1 according to Figure 1 in cross section with the housing cover 9 attached. The web 18 now lies all around the flat 17, which both overlap. To this area this overlap is now directed all around a laser beam 20 which is aligned and dimensioned in terms of its intensity so that the two facing surfaces of the flat 17 and the web 18 warm up and begin to melt. This will fuse at this point, the throttle valve housing 2 with the housing cover 9, so that the gear housing located under the housing cover 9 6 and the drive housing 7 are sealed. There is no need to insert and mount a seal. The housing cover 9 is non-detachably connected to the throttle valve housing 2 means that it cannot move off without destroying the components involved the throttle body 2 are solved. This has besides the absolute Tightness still has the advantage that all components in this room are arranged, are protected from manipulation. This is particularly so then advantageous if covered in the throttle valve housing 2 an electronic control unit housed by the housing cover 9 is.

The housing cover 9 shown in FIG. 3 also has a counter bearing 21 with which the drive shaft of the electric motor, not shown, is mounted is. Likewise, the throttle valve shaft can also be used by means of a counter bearing 22 4 be counter-positioned.

Figure 4 shows the throttle body 1 in longitudinal section according to the Figure 1. It can be seen here that the metal cylinder 12 as a simple cylinder is formed, the outer peripheral surface and at least part of the end faces surrounded by the plastic of the throttle valve housing 2 is. The inward facing inner wall of the metal cylinder 12 is straightforward, but can also be specified for implementation Characteristic curves for volume throughput must be contoured. Such configurations are shown for example in FIG. In Figure 4 is the throttle valve 5 shown in its closed position and can be turned by twisting clockwise to an open position with a rotation of about 90 ° (i.e. up to one when viewed 4 roughly vertical position) corresponds to the full load position.

FIG. 5 shows the throttle valve connector 1 according to FIG. 1 in a sectioned, three-dimensional view, again the arrangement of the metal cylinder 12 is visible in the throttle valve housing 2. Likewise One can see a possibility of mounting the throttle valve 5 on the Throttle valve shaft 4. The throttle valve shaft 4 has a slot, into which the throttle valve 5 can be inserted, the throttle valve 5 after alignment in their target position on the throttle valve shaft 4 immovable is fixed. This can be done, for example, with pins or screws done by the throttle valve shaft 4 and the throttle valve 5 can be inserted. Alternatively, the throttle valve 5 can also in the Slot caulked with the throttle valve shaft 4 or glued.

Figure 6 shows the throttle valve connector 1 in section in a modified Version compared to Figure 1, wherein it can be seen that the metal cylinder 12 not only the extensions 14 for receiving the bearings 15, 19 for the throttle valve shaft 4, but also a bearing plate 23 includes one end of the actuator designed as an electric motor receives. This increases strength, with another advantage It should be mentioned that one over the end shield 23 during operation of the Electric motor generates heat loss on the inner wall of the metal cylinder 12 is performed, at which point the heat loss through the air flowing through the line section 3 (or the fuel / air mixture) is dissipated. The bearing plate 23 also improved the thermal properties of the throttle valve body 1.

FIG. 7 shows the throttle valve connector 1 in longitudinal section according to FIG. 1, here the metal cylinder 12 is shown with an inner contour. In the FIG. 7 clearly shows that the metal cylinder 12 in the plastic throttle body is used or is surrounded by the plastic such that the metal cylinder 12th is held securely in the throttle body 2 while the inner wall of the metal cylinder 12 is not covered by plastic, that is metallic properties are retained. The throttle valve 5 is by rotating the throttle valve shaft 4 - when looking at Figure 7 in Clockwise - in a pivoting direction 24 from that shown in Figure 7 Minimum position in which the line section 3 is completely or almost is completely closed, pivotable. The line section 3 Air flowing through (or the fuel-air mixture) has a direction of flow 24. By pivoting the throttle valve 5 in the pivoting direction 24 becomes the line section 3 with increasing pivoting opened further so that through an inner contour 26 of the metal cylinder 12th a characteristic curve of the volume flowing through the line section 3 in Depending on the opening angle of the throttle valve 5 is adjustable. Through different inner contours 26 with different metal cylinders 12 can be realized while maintaining a standardized Throttle body 2 in a simple way different, Characteristic curves adapted to the respective internal combustion engine type will be realized. The inner contour 26 of the metal cylinder shown in FIG. 7 12 is above and below the throttle valve shaft 4 symmetrical, in the swivel direction 24, starting from that in FIG. 7 Minimum position (or also zero position) of the throttle valve 5 shown the inner contour 26 initially has a straight cylindrical section, which is followed by an arcuate section.

The aim should be that in the transition area between the inner wall the line section 3 and the inner wall of the metal cylinder 12 there is no paragraph to avoid turbulence in the air or Avoid fuel air mixture in the flow direction 25.

However, it should be noted that the inner contour shown in Figure 7 26 of the metal cylinder 12 is only exemplary and any other Contours (also above and below the level of the throttle valve shaft 4 asymmetrical contours) during manufacturing and / or processing of the metal cylinder 12 can be achieved.

LIST OF REFERENCE NUMBERS

1.

throttle body

Second

throttle body

Third

line section

4th

throttle shaft

5th

throttle

6th

gearbox

7th

drive housing

8th.

plug

9th

housing cover

10th

flange

11th

drilling

12th

metal cylinder

13th

execution

14th

extension

15th

camp

16th

room

17th

flattening

18th

web

19th

camp

20th

laser beam

21st

thrust bearing

22nd

thrust bearing

23rd

end shield

24th

pan direction

25th

flow direction

26th

inner contour

Claims (5)

1. Butterfly valve connector piece (1), comprising a butterfly valve housing (2) made of plastic, a butterfly valve (5) being pivotably mounted in a line section (3) of the butterfly valve housing (2), and an annular insertion part being provided in the line section (3), at least in a partial pivoting range of the butterfly valve (5), characterized in that the insertion part is embodied as a metal cylinder (12) and is designed to hold further elements of the butterfly valve connector piece (1).
2. Butterfly valve connector piece (1) according to Claim 1, characterized in that the metal cylinder (12) is inserted into the plastic of the butterfly valve housing (2), the metal inner wall of the metal cylinder (12) being exposed in the region of the line section (3).
3. Butterfly valve connector piece (1) according to Claim 1 or 2, characterized in that the metal cylinder (12) is provided in a flow direction (25) below and/or above a butterfly valve shaft (4) which is fitted with the butterfly valve (5).
4. Butterfly valve connector piece (1) according to one of Claims 1 to 3, characterized in that the metal cylinder (12) is designed to be the holder for the bearings (15, 19) of the butterfly valve shaft (4).
5. Butterfly valve connector piece (1) according to one of the preceding claims, characterized in that the metal cylinder (12) has an inner contour (26) in order to obtain a predefinable characteristic curve for the volume throughput rate through the line section (3) as a function of the pivoting of the butterfly valve (5).

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