EP3181874B1 - Throttle valve housing for a throttle valve arrangement for a combustion engine - Google Patents

Description

The present invention relates to a throttle body according to the subject-matter of independent claim 1.

Throttle valve assemblies for internal combustion engines have long been known. In the supply air line of an internal combustion engine, such throttle valve arrangements are provided in order to be able to control the amount of air flowing into the engine in a targeted manner, so that it is possible to influence the output power of gasoline engines by adjusting the air-fuel ratio. In the case of diesel engines, throttle valve arrangements in the incoming air stream have a different meaning, namely with regard to adjusting the recirculation rate of exhaust gases. In the exhaust system of internal combustion engines, throttle valve arrangements are frequently used for influencing noise emissions and for influencing the back pressure in the exhaust gas system. Due to the thermal load throttle body are usually made of metal.
Common to the throttle valve assemblies that is influenced by pivoting the throttle valve in the throttle body, the flow cross-section and thus the flow resistance between the inlet and the discharge opening. The inflow opening is used to hold a fluid - usually of fresh air, exhaust gas or a mixture of both - in the throttle body. Accordingly, the fluid escapes via the discharge opening from the throttle body. The flow path between the inflow port and the outflow port is influenced by the throttle valve.
It is readily apparent that a quality feature for throttle assemblies is the degree of tightness achieved in the throttle closed position. Of course, in the production of throttle valve assemblies, this degree of tightness must be reproducible with high accuracy to achieve consistent quality.
Throttle valve arrangements are frequently known from the prior art in which the throttle body is completely uncontoured even in the area of movement of the throttle valve, so that the throttle valve forms a sealing gap in the closed position with the throttle body which, viewed in the direction of flow, thus flows from the inlet opening the flap housing looking to the outflow opening, can be seen. The throttle is then practically perpendicular to the wall of the throttle body. It is also known, in the movement space of the throttle body and that on the wall of the throttle body additional material - for example, in the form of an integrally formed on the wall of the throttle body plate - to install, so that a stop for the throttle valve is formed in its closed position. This is easy, for example, if the throttle body is a circular tube into which then just a slightly smaller pipe or half pipes or pipe segments are introduced as a stop. This is relatively expensive, on the one hand because additional structural elements must be placed in the cramped dimensions of the throttle body and there must be precisely positioned, on the other hand, because a further process step for fixing these structural elements is carried out. Also arises in the assembly of the throttle body and the additional sealing elements again the question of a reliable to be realized tightness (problem of gap formation).

DE4408909A1 discloses a throttle body, wherein the sealing ridge is formed spanfrei in the wall of the throttle body.

DE4329526A1 discloses a method of manufacturing a throttle body wherein the seal bar is made in the throttle body by forming.

The object of the present invention is to provide a throttle body with improved sealing properties, and a corresponding method for producing such a throttle body.

The above-indicated and derived object is achieved in a throttle body according to the subject of independent claim 1. Due to the chip-free design of the sealing web in the wall of the throttle body is made clear that the sealing web is made with the material of the wall and no additional elements for the realization of the sealing web are introduced into the throttle body. Such a throttle body can be prepared by machining the chip-free forming, so for example by applying the high pressure forming or by pressing the wall material of the throttle body into a correspondingly contoured counter-mold with a rigid die (female-male forming).
Such a throttle body is therefore particularly advantageous because not only simple geometries of the movement space of the throttle and simple throttle body geometries can be realized, but virtually any contours can be realized.
It when the throttle body and the sealing web of the throttle body are made of a one-piece pipe part by chip-free forming is particularly advantageous. Circular tubes can also be used to produce non-circular throttle bodies, especially in the area of the movement space of the throttle valve.
In an advantageous embodiment of the throttle body, it is provided that the sealing web is formed in the movement space everywhere where the throttle valve terminates only in the closed position with the throttle body. Thus, the sealing web does not have to be a completely and closed circumferential sealing contour, but instead the sealing web is only formed where it can also unfold a corresponding sealing and stopping action with respect to the throttle valve. It can be provided, for example, that the throttle valve is attached to a shaft which extends centrally through the flow cross-section of the movement space of the throttle body. When pivoting the throttle valve with such a shaft inevitably moves a part of the throttle valve against the flow direction and the other part of the throttle valve in the flow direction.

At the location of the shaft itself, the throttle valve is practically not moved, at least not moved in the sense of a release and a closing of a flow cross-section. Accordingly, in the area of the shaft, the sealing web must not be executed. It can be seen from this example that the sealing web can be formed by a plurality of sealing web segments, which are formed along the sealing contour in and with the throttle body.

According to the invention, the sealing web has a triangular profile with a flow flank, with a sealing flank and with a dome, wherein the flow flank and the sealing flank originate from a respective base level of the throttle body with a foot point and converge in the dome. The dome protrudes furthest into the flow cross section. The sealing flank is formed on the side of the sealing web on which the throttle valve strikes in the closed position. The flow flank is consequently arranged on the other side, ie opposite the sealing flank. Such a geometry of the sealing bar is particularly easy to produce and also gentle to the material. Due to the non-cutting shaping of the wall of the throttle body, a material flow is practically always to effect, which can significantly burden the formed material. The stress is greatest where the largest internal material displacement is effected, since the structure of the material is changed the most there. With a triangular configuration of the sealing web, it is possible to realize a sealing structure with comparatively smooth contours. The triangular profile also has fluidic advantages, since the guided through the throttle body fluid flow is performed continuously and without offset through the edges of the sealing land, so that the influence of the sealing land is fluidically relatively low.
It is particularly preferably provided that in the sealing flank between its base and the dome a flat sealing area is formed. In a tubular throttle body so practically a circumferential sealing surface is realized, which - looking in or opposite to the flow direction of the sealing edge - forms a sealing ring. This is advantageous because it is particularly easy to also just form the parts of the throttle, in the closed position of the throttle valve face the flat sealing region of the sealing edge.

According to the invention, the triangular profile of the sealing web is formed asymmetrically, wherein the sealing edge is steeper than the flow edge. It has proven to be advantageous to let the sealing edge run relatively steep, so with a very large slope in the flow cross section. One reason for this is that the sealing flank is then inclined only very slightly with respect to the flow cross-section and thus with respect to the throttle valve located in the closed position, which is then usually positioned in the flow cross-section, ie perpendicular to the flow direction. If the throttle valve should rest not only with a narrow edge on its outer boundary on the sealing edge of the sealing strip circumferentially, but a better sealing effect is to be achieved, then the throttle should lie flat in the closed position on the sealing edge of the sealing web, so that realizes a circumferential sealing surface becomes. In this area, the throttle must thus form a correspondingly molded counterpart to the sealing edge. The steeper the sealing flank protrudes into the flow cross-section, the less must the throttle flap be bevelled in its sealing edge region, deviating from the pure shape of a flat disk. A disadvantage of the steep profile of the sealing flank in the flow cross-section is that the material load by non-cutting forming, for example by hydroforming, in this area is very high, since with little material, a relatively large deformation must be realized.
Due to the mentioned asymmetrical design of the sealing web, the flow flank extends flatter than the sealing flank, so that significantly more material of the wall of the throttle body is available compared to the sealing flank to form the flow flank from its base to the crest.
Overall, the asymmetrical design of the triangular sealing bar profile results in a comparatively small proportion of the area of the sealing bar - namely that in the region of the flow flank - being subjected to a comparatively small amount is and that a better stiffness than in a symmetrical design is achieved. The chip-free design of the sealing web in the wall of the throttle body allows a precise realization of the angle of attack of the sealing flank and also a precise realization of a flat sealing area, in which case a slightly larger material load is accepted than at the flow flank.
The realization of a provided on the outer periphery of the throttle aperture with a slope corresponding to the slope of the sealing edge is also advantageous because in this way also causes a stiffening of the throttle itself. The inclination of the sealing flank additionally leads to the fact that the sealing surface is increased, in any case with respect to a vertically extending sealing flank, which therefore runs perpendicular to the flow direction.

It is preferably provided that the plane sealing area of the sealing flank is inclined more than 70 °, more preferably more than 75 ° and most preferably about 80 ° with respect to the flow axis of the throttle body.

Accordingly, it is provided in the asymmetrical design of the sealing web that the flow flank is inclined less than 50 °, more preferably less than 40 ° and most preferably about 35 ° relative to the flow axis of the throttle body.

The invention also relates to a method for producing a throttle body for a throttle assembly for an internal combustion engine according to the subject-matter of independent claim 10. The initially derived object is achieved in this method in that a one-piece pipe part is reshaped so that the sealing web is produced in the throttle body by chip-free forming.

According to the invention, the tube part is deformed by pressure effect from the inside to the outside, so that a material flow is brought to the outside in a shaping outer tool, in particular by hydroforming or by moving a rigid inner tool into a rigid outer tool.

Fig. 1

ein erfindungsgemäßes Drosselklappengehäuse in perspektivischer Ansicht,

Fig. 2

ein erfindungsgemäßes Drosselklappengehäuse in Draufsicht mit Dichtstegprofil und Ausnehmung für eine Antriebswelle,

Fig. 3

schematisch das Dichtstegprofil gemäß Fig. 2,

Fig. 4

eine Detailansicht des Dichtsteges im Bereich der Ausnehmung für eine Antriebswelle,

Fig. 5

eine schematische Draufsicht für eine erste Realisierung des Dichtstegs im Bereich der Ausnehmung für eine Antriebswelle und

Fig. 6

eine schematische Draufsicht für eine zweite, alternative Realisierung des Dichtstegs im Bereich der Ausnehmung für eine Antriebswelle.

In particular, the method is carried out so that the above-described subject features of the throttle body are realized.
In particular, there are now a variety of ways to design and further develop the throttle assembly and the method for producing such a throttle assembly. Reference is made to both the claims subordinate to the independent claims and to the following description of preferred embodiments in conjunction with the drawings. In the drawing show

Fig. 1

an inventive throttle body in perspective view,

Fig. 2

an inventive throttle body in plan view with sealing bar profile and recess for a drive shaft,

Fig. 3

schematically the sealing bar profile according to Fig. 2 .

Fig. 4

a detailed view of the sealing web in the region of the recess for a drive shaft,

Fig. 5

a schematic plan view of a first realization of the sealing ridge in the region of the recess for a drive shaft and

Fig. 6

a schematic plan view of a second alternative realization of the sealing ridge in the region of the recess for a drive shaft.

In the Fig. 1 to 5 are shown in varying degrees of detail and with different focuses throttle body 1. Throttle body forms together with the throttle valves installed in them throttle valve assemblies; the throttle valves are not shown here themselves, of particular interest are the throttle body 1.

Throttle body 1 serve to accommodate a pivotally mounted throttle and therefore form the space for movement of the throttle. The throttle body 1 has on a first side an inflow port 2 for receiving a fluid, and the throttle body 1 has on a second side an exhaust port 3 for discharging the throttle body 1 by flowing fluid; characterized the flow direction D is defined.

In the movement space of the throttle body 1, a projecting into the flow cross-section sealing ridge 4 is arranged, which serves as a stop of the throttle valve in the closed position. It is important here that the sealing web 4 is formed without chips in the wall of the throttle body 1. In the embodiments shown here, the throttle body 1 and the sealing web 4 of the throttle body 1 are made of a one-piece pipe part by chip-free forming. The throttle body 1 shown in the figures has been made by hydroforming using a solid but flexible forming medium. As a molding medium, a polyurethane elastomer has been used. The medium is introduced into the blank of the throttle body 1, axially, thus compressed in the flow direction D, whereby the material escapes radially and presses the wall of the blank in an unillustrated outer tool, whereby the end-formed Throttle body 1 is formed, which is shown in the figures. Fluide forming media can also be used.

In the Fig. 1 . 2 and 4 to 6 it can be seen that the sealing web 4 is formed in the movement space where the throttle valve terminates only in the closed position with the throttle body 1; in the region of the shaft opening 5 or around the shaft opening 5, the sealing web 4 is not formed. This results in two nearly semicircular sealing bar segments, which are incoherent and together form the sealing bar 4.

In the FIGS. 2 to 4 , especially in the detail of Fig. 3 is clearly visible that the sealing ridge 4 has a triangular profile with a flow edge 6, with a sealing edge 7 and a dome 8, wherein the flow edge 6 and the sealing edge 7 each originate from a base level G of the throttle body 1 with a base FP and in the dome 8 converge. The base level is formed by the straight course of the wall of the throttle body, starting from which the contouring of the wall by the sealing web 4 begins. The dome 8 is the element which projects furthest into the flow cross section. The sealing flank 7 is formed on the side of the sealing web 4, against which the throttle valve strikes in the closed position.

In the sealing edge 7, a flat sealing region 9 is formed between its base FP and the dome 8. This is particularly advantageous because a correspondingly flat counter surface can be formed without much effort on the throttle, for example in the form of an applied aperture. As a result, a significantly better sealing effect is achieved than if the sealing web 4 and the throttle valve would only seal against one another in a line-shaped contact contour.

The triangular profile of the sealing web 4 is formed asymmetrically, wherein the sealing edge 7 is steeper than the flow edge 6. The planar sealing region 9 is inclined at about 80 ° with respect to the flow axis or the flow direction D, respectively, relative to the base level G of the throttle body 1.

In Fig. 3 is good to see that the sealing edge 7 fußpunktseitig reaches below the base level of the throttle body 1, namely the base level by the distance h below. The reshaped contour runs arcuately in the base level G of the throttle body 1. This "undershooting" of the contour profile causes larger Umformradien can be realized with a smaller material load. In addition, a larger, even sealing area 9 can be realized in this way since the sealing area 9 is widely spaced from the outlet area of the arcuate section at the root FP of the sealing flank 7.

Fig. 3 indicates that the flow edge 6 is inclined about 35 ° relative to the flow axis D of the throttle body 1 and thus with respect to the base level G of the throttle body 1.

In the Fig. 1 . 2 and 4 to 6 in each case at least one circular opening region 5 is shown as a passage point for a drive shaft 10; the shaft 10 is only in the Fig. 5 and 6 shown schematically. When the throttle body 1 is formed by hydroforming, the only defined opening area 5 is still closed; he will be opened afterwards, here by laser cutting.

In the embodiment shown in the figures, the sealing web 4 eccentrically to the opening portion 5, wherein the height of the sealing ridge 4 ramps down to the level of the boundary of the defined opening portion 5. The height of the sealing web 4 is thus already switched off on reaching the border of the opening area 5 to zero. In the Fig. 4 perspective situation is shown in Fig. 5 shown again simplified, wherein the shaft 10 has entered the place of the defined opening area 5. This is necessary in order to be able to recognize the advantageousness of the construction described. Although the height of the sealing web 4 drops in a ramp shape, that is to say along the ramp 11, to the level of the boundary of the defined opening region, it is considered in the flow direction (FIG. Fig. 5 below) realized over the full circumference almost closed sealing ring, also directly on the shaft 10th

An alternative realization is in Fig. 6 shown. Again, the sealing ridge 4 off-center on the circular opening portion 5 as a passage point for the drive shaft 10, the in Fig. 6 has taken the place of the opening area 5. The height of the sealing web 4 remains unchanged up to the boundary of the defined opening area 5 or up to the shaft 10. In Fig. 6 above is indicated that the ramp 11 only in the region of the potential opening 5, here replaced by the shaft 10, drops. Even so, as seen in the flow direction, a closed sealing contour can be realized, but then the boundary of the opening 5 is no longer circular.

reference numeral

1

throttle body

2

inflow

3

outflow

4

sealing land

5

Opening area for shaft

6

flow edge

7

sealing edge

8th

knoll

9

level sealing area

10

wave

11

ramp

Claims (11)

1. Throttle valve housing (1) for a throttle valve arrangement for an internal combustion engine, wherein the throttle valve housing (1) is used to accommodate a pivotally mounted throttle valve and provides movement space for the throttle valve, wherein the the throttle valve housing (1) has an inflow opening (2) on a first side for receiving a fluid and the throttle valve housing (1) has an outflow opening (3) on a second side for dispensing a fluid and wherein at least one sealing piece (4) projecting into the flow cross-section is arranged in the movement space of the throttle valve housing (1) and is used as a stop for the throttle valve housing in the closed position, wherein the sealing piece (4) is formed in the wall of the throttle valve housing (1) in a non-cutting manner, wherein the sealing piece (4) has a triangular profile with a flow edge (6), with a sealing edge (7) and with a tip (8), wherein the flow edge (6) and the sealing edge (7) each originate from a base level G of the throttle valve housing (1) with a base point FP and converge at the tip (8), wherein the tip (8) projects furthest into the flow cross-section and wherein the sealing edge (7) is formed on the side of the sealing piece (4) that the throttle valve strikes in the closed position,
   wherein the triangular profile of the sealing piece (4) is designed asymmetrically
   characterized in
   that the sealing edge (7) reaches below the base level (G) of the throttle valve body (1) at the base point.
2. Throttle valve housing (1) according to claim 1, characterized in that the throttle valve housing (1) and the sealing piece (4) of the throttle valve housing (1) are manufactured from a one-piece tubular part by non-cutting transformation.
3. Throttle valve housing (1) according to claim 1 or 2, characterized in that the sealing piece (4) is formed in the movement space everywhere, where the throttle valve closes with the throttle valve housing (1) in the closed position.
4. Throttle valve housing (1) according to any one of claims 1 to 3, characterized in that a smooth sealing region (9) is formed in the sealing edge (7) between its base point FP and the tip (8).
5. Throttle valve housing (1) according to any one of claims 1 to 4, characterized in that the sealing edge (7) is steeper than the flow edge (6), wherein the smooth sealing region (9) is preferably inclined more than 70°, especially preferably more than 75°, very preferably about 80° relative to the flow axis D or the base level line G of the throttle valve housing (1).
6. Throttle valve housing (1) according to any one of claims 1 to 5, characterized in that the sealing edge (7) forms an arc running into the base level line G of the throttle valve housing (1).
7. Throttle valve housing (1) according to any one of claims 1 to 6, characterized in that the flow edge (6) is preferably inclined less than 50°, especially preferably less than 40°, very preferably about 35° relative to the flow axis D or the base level line G of the throttle valve housing (1).
8. Throttle valve housing (1) according to any one of claims 1 to 7, characterized in that at least one circular opening region (5) is specified as a passage point for an actuator shaft (10) of the throttle valve, wherein the sealing piece (4) runs off-center towards the opening region (5), wherein the height of the sealing piece (4) slopes downward in a ramp-like manner to the level of the edge of the specified opening region (5).
9. Throttle valve housing (1) according to any one of claims 1 to 7, characterized in that at least one circular opening region is specified as a passage point for an actuator shaft (10) of the throttle valve, wherein the sealing piece (4) runs off-center towards the opening region (5), wherein the height of the sealing piece (4) remains unchanged up to the edge of the specified opening region (5) and the height of the sealing piece (4) then slopes downward in a ramp-like manner.
10. Method for producing a throttle valve housing (1) for a throttle valve arrangement for an internal combustion engine, wherein the throttle valve housing (1) is used to accommodate a pivotally mounted throttle valve and provides movement space for the throttle valve, wherein the the throttle valve housing (1) has an inflow opening (2) on a first side for receiving a fluid and the throttle valve housing (1) has an outflow opening (3) on a second side for dispensing a fluid and wherein at least one sealing piece (4) projecting into the flow cross-section is arranged in the movement space of the throttle valve housing (1) and is used as a stop for the throttle valve housing in the closed position,
    characterized in
    that the sealing piece (4) is formed in the wall of the throttle valve housing (1) in a non-cutting manner, wherein the sealing piece (4) has a triangular profile with a flow edge (6), with a sealing edge (7) and with a tip (8), wherein the flow edge (6) and the sealing edge (7) each originate from a base level G of the throttle valve housing (1) with a base point FP and converge at the tip (8), wherein the tip (8) projects furthest into the flow cross-section, wherein the sealing edge (7) is formed on the side of the sealing piece (4) that the throttle valve strikes in the closed position, wherein the triangular profile of the sealing piece (4) is designed asymmetrically, wherein the sealing edge (7) reaches below the base level (G) of the throttle valve body (1) at the base point,
    wherein the throttle valve housing (1) and the sealing piece (4) of the throttle valve housing (1) are manufactured from a one-piece tubular part by non-cutting transformation, namely by transforming the tubular part from the inside to the outside using internal high pressure forming, so that an outward material flow into an external forming tool is caused.
11. Method according to claim 10, characterized in that the tubular part is transformed into a throttle valve housing (1) with a sealing piece (4) according to the characterizing part of any one of claims 3 to 9.

Images