Throttle device for an air supply system

Abstract

Throttle device (10) for an air supply system (100) of an internal combustion engine, comprising an air duct (20) with an inner wall (22) and a throttle valve (30) with an upper valve half (32) and a lower valve half (34), wherein the throttle valve (30) is rotatably mounted for a rotational path (R) between a closed position (S) and an open position (O) at a pivot point (D) which is arranged between the two valve halves (32, 34) in the air duct (20), wherein a sealing device (40) is provided for sealing one of the two valve halves (34) against the inner wall (22) over a part of the rotational path (R) adjacent to the closed position (S), characterized in that the sealing device (40) has a wall wedge (44) which is arranged on the inner wall (22) and which defines the cross-section of the air duct (22) along the part to be sealed. Rotation path (R) reduced,wherein the wall wedge (44) has a sealing surface (44a) with a radius of curvature corresponding to the cross-sectional radius of the air duct (22).

Description

[0001] The present invention relates to a throttle device for an air supply system of an internal combustion engine and an air supply system of an internal combustion engine.

[0002] Throttle devices for air supply systems of internal combustion engines are generally known. They serve to regulate the air supply to the combustion chamber of an internal combustion engine. For this purpose, known throttle devices feature a throttle flap that is rotatably mounted in an air duct. The mounting is provided at a pivot point located between the two flap halves. This allows the throttle flap to be moved between a closed position and an open position along a rotational path. By arranging the pivot point between the two flap halves, a symmetrical opening movement of the throttle flap is achieved in known throttle devices. In this way, each flap half seals off the outside against the inner wall of the air duct in the closed position.When the valve rotates from the closed position toward the open position, the sealing position at the edges of the respective valve half detaches from the inner wall, allowing airflow to pass through the throttle valve on both sides. As the throttle valve continues to move, the two valve halves open symmetrically, resulting in a symmetrical or essentially symmetrical distribution of the airflow around the two valve halves of the throttle valve.

[0003] Furthermore, it is known that generating a vortex inside the combustion chamber of an engine is beneficial in terms of fuel efficiency during combustion within the combustion chamber of the internal combustion engine. For example, it is known to use specially shaped air ducts that generate such swirling. It has also been proposed, for example, in WO 2005 / 047668 A1, that a cross-sectional constriction in the air duct upstream of the throttle valve creates an asymmetrical distribution of the air flow as it passes between the two valve halves.

[0004] However, the disadvantage is that the methods known to date are only partially suitable for generating the desired vortex. In particular, the quantitative expression of such a vortex is not yet sufficient to achieve significant changes in fuel consumption efficiency during combustion in the combustion chamber.

[0005] Further printed prior art in the field of the present invention is known from DE 10 2007 000 079 A1, DE 37 04 717 A1, US 6 971 632 B2 DE 696 04 084 T2 and DE 11 2007 000 631 T5.

[0006] The object of the present invention is to at least partially remedy the disadvantages described above. In particular, the object of the present invention is to provide a throttle device for an air supply system of an internal combustion engine and an air supply system of an internal combustion engine, which allow the generation of a vortex in the combustion chamber of the internal combustion engine in a cost-effective and simple manner.

[0007] The above object is achieved by a throttle device having the features of claim 1 and by an air supply system having the features of claim 8. Further features and details of the invention emerge from the subclaims, the description, and the drawings. Features and details described in connection with the throttle device according to the invention naturally also apply in connection with the air supply system according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0008] A throttle device according to the invention for an air supply system of an internal combustion engine has an air duct with an inner wall. Furthermore, a throttle valve with an upper valve half and a lower valve half is provided. The throttle valve is rotatably mounted on a pivot point for a rotational path between a closed position and an open position. This pivot point is arranged between the two valve halves in the air duct. A throttle device according to the invention is characterized in that a sealing device is provided for sealing one of the two valve halves against the inner wall over a part of the rotational path adjacent to the closed position. A throttle device according to the invention is therefore basically designed in a known manner, namely with two valve halves, wherein the rotatable mounting in the air duct takes place between the two valve halves.This means that the throttle valve according to the invention can preferably be controlled or operated in the same or essentially the same way as is the case with known throttle devices. According to the invention, however, the throttle device is further developed such that a seal against the inner wall is created via the sealing device in a single one of the two valve halves, i.e. only or exclusively one of the two valve halves. Sealing is to be understood as preventing air flow against this sealing device, with sealing meaning preventing air flow by more than 90% in particular. It is therefore not essential to achieve a completely airtight seal, but rather only a technically effective seal, in order to provide a sealing device according to the invention.Furthermore, in the context of the present invention, only a part of the rotation path from the closed position is sealed.

[0009] If a throttle device according to the invention is moved out of the closed position, in contrast to known throttle devices, a fluid path for air flow is only opened up at the other, unsealed flap half. The flap half that is operatively connected to the sealing device remains sealed, so that despite the throttle valve beginning to open, upon leaving the closed position, air flow is released in an asymmetric manner only through one of the two flap halves. Only when the sealing by the sealing device is ended, i.e. the flap half has left the part of the sealing rotation path, can flow around the throttle valve on both sides, so that flow around the throttle valve occurs on both sides, i.e. past both flap halves, although preferably still in an asymmetric manner.

[0010] A throttle device according to the invention creates an asymmetrical flow around the throttle valve after leaving the closed position, i.e., with respect to the effect in the combustion chamber during partial and low-load ranges. In these ranges, an increase in efficiency is particularly advantageous with regard to the consumption characteristics during fuel combustion in the combustion chamber. As the throttle valve moves further, the remaining cross-section of the air duct is released, so that in the full-load range, the sealing device preferably has only a minor influence on the air flow in the air supply system. Accordingly, by simply modifying the device and providing the sealing device, an asymmetrical inflow into the combustion chamber can be achieved by asymmetrically passing through the throttle valve.This asymmetrical flow into the combustion chamber creates the swirl in the desired manner, so that a reduction in consumption in the partial load range can be achieved through lower cycle fluctuations, shorter ignition delay and shorter combustion duration.

[0011] In a throttle device according to the invention, the duct and the throttle valve are preferably round or substantially round. Such a round cross-section preferably enables a substantially semicircular sealing surface of the respective valve half upwards and downwards. For the purposes of the present invention, the closed position is a throttle valve which is perpendicular or substantially perpendicular to the longitudinal axis of the air duct. A deviation of up to 5° from the perpendicular to the longitudinal axis of the air duct is conceivable. This deviation serves in particular to provide leakage air in order to prevent damage to the internal combustion engine when the throttle valve is completely closed. This leakage air can also be sealed by the sealing device in one of the two valve halves.The open position is preferably a position in which the throttle valve is aligned substantially along the longitudinal axis of the air duct. A deviation of up to 5° from the longitudinal axis of the air duct can be tolerated. In this position, the largest possible cross-sectional area of ​​the air duct is made available as a free cross-section, allowing airflow through the throttle valve toward the combustion engine.

[0012] A throttle device according to the invention can be further developed in such a way that the sealing device is designed to seal one of the two valve halves over a portion of the rotational path adjacent to the closed position of less than 30°. This limits the sealing to a portion of the rotational path, particularly with respect to an open position that covers a rotational path of 90° from the closed position, which correlates in particular with the partial load range or the low load range with respect to the operating mode of the internal combustion engine. This ensures that the sealing device is ineffective in the full load range of the internal combustion engine, thus preferably enabling an ideal and complete air supply around the throttle valve into the internal combustion engine.In other words, under full load, the otherwise sealed part of the throttle valve also opens, in particular the lower half of the throttle valve.

[0013] It is further advantageous if, in a throttle device according to the invention, the sealing device has a flap wedge which is arranged on the side of the flap half to be sealed facing away from the air flow. This flap wedge has the greatest thickness at the end of the flap half to be sealed facing the inner wall. This allows a modification of a known throttle device by replacing only the throttle flap. Such a flap wedge serves, via its ramp-like structure, to provide a seal between the flap half to be sealed and the inner wall, despite an incipient rotation from the closed position of the throttle valve. The flap wedge preferably extends completely to the end of this flap half facing the inner wall.Furthermore, the ramp or the flap wedge is preferably designed such that it extends in the direction of the pivot point essentially all the way to the pivot point. This is a particularly simple and cost-effective embodiment that can also be used in particular with existing designs. This embodiment can also be implemented with existing control systems, since no design changes to the throttle valve actuator are necessary. When the throttle valve leaves the closed position, the outer section of the flap wedge moves along the inner wall and thus achieves a seal on this side of the throttle valve despite leaving the closed position. The flap wedge thus forms part of or completely the sealing device in the manner according to the invention.If the throttle valve and the air duct have a round cross-section, this valve wedge is understood as a wedge-shaped cross-section within the meaning of the present invention. Accordingly, this valve wedge extends along a semicircular line defined by the end of the valve half to be sealed facing the inner wall.

[0014] It is also advantageous if, in a throttle device according to the invention, the flap wedge has a curved outer surface facing the inner wall. This has, in particular, a radius of curvature that corresponds or substantially corresponds to the cross-sectional radius of the air duct. This relationship between a curved outer surface of the flap wedge, in particular correlating with the cross-sectional radius of the air duct, enables a particularly tight seal between the flap wedge of the sealing device and the inner wall. The gap that remains between the sealing device and the inner wall after leaving the closed position is thus minimized, thus enhancing the sealing effect.

[0015] A further advantage is achieved in that, in a throttle device according to the invention, the sealing device has a wall wedge arranged on the inner wall and reducing the cross-section of the air duct along the part of the rotation path to be sealed. This embodiment may be an alternative design of the sealing device.

[0016] Of course, a combination with other components and / or embodiments of the sealing device, for example with a flap wedge, is also conceivable. A seal along the part of the rotation path to be sealed is to be understood in such a way that the wall wedge is arranged in a region of the inner wall whose outer surface is directly opposite or preferably even in contact with the end of the flap half to be sealed facing the inner wall. This can be referred to as a direct correlation of the wall wedge with the flap half. In particular, there is no gap, or only a very small gap, between the flap half to be sealed and the sealing surface of the wall wedge defined in this way. For example, this wall wedge is created directly during the manufacture of the air duct, for example by mechanical processing, preferably in the form of a milling step.This has the advantage that little or no intervention in the function and design of the throttle valve is necessary. Rather, by modifying the manufacturing process for the air duct, a throttle device according to the invention can be manufactured particularly cost-effectively. Another advantage is that this wall wedge can be made particularly small in relation to the flow cross-section of the air duct. This means that, particularly in full-load situations, only a small amount of additional resistance or only a small reduction in the free flow cross-section of the air duct is generated by the wall wedge. This means that, despite the mode of operation according to the invention, the full-load range can be designed with only minor restrictions in terms of the achievable power or torque in the partial-load range or low-load range.

[0017] It is furthermore advantageous if, in a throttle device according to the invention, the wall wedge has a sealing surface with a radius of curvature that corresponds or substantially corresponds to the cross-sectional radius of the air duct. Here, the same advantages can be achieved as have already been explained for the corresponding embodiment of the flap wedge. In particular, a gap is reduced during movement over the part of the rotation path to be sealed between this sealing surface of the wall wedge and the end of the flap half facing the inner wall. In addition, the rear side of the wall wedge can be designed to be flow-optimized in the upstream flow direction. In particular, a wedge-shaped design of the wall wedge is provided there, so that vortex formation or turbulent flow regions are reduced or avoided.

[0018] It is also advantageous if, in a throttle device according to the invention, the two flap halves can be moved at least partially independently of one another, with the sealing device being formed at least in section by one of the two flap halves. This embodiment can also be used alternatively or in addition to the embodiments of a throttle device according to the invention described in the preceding paragraphs. The two flap halves can, for example, be moved by two separate servomotors. Thus, separate movement of the two flap halves serves to enable particularly precise control for all load ranges. In this way, the asymmetry of the flow around the throttle valve can be precisely adjusted for each throttle valve position by targeted and specific control of the two flap halves separately from one another.In this embodiment, the sealing device is formed by one of the two valve halves and preferably by a corresponding control device or adjusting device. A major advantage of this variant is that, at full load, the two valve halves are preferably positioned relative to each other in the same way as would be the case with a single-piece throttle valve. This avoids the need for an obstructive component under full load, so that the full power and thus the full torque of the internal combustion engine are available even with a throttle device according to the invention.

[0019] In the throttle device of the embodiment explained in the previous paragraph, it can be advantageous if one of the two flap halves has a driver which, from a predefined rotational position of the other flap half, strikes this other flap half. In other words, the driver forces one flap half to rotate with the other flap half. It is possible for the driver to be arranged on the flap half to be sealed as well as on the flap half that opens first. Of course, more than one driver can also be provided in order to be able to return the flap halves to the sealing position in the manner according to the invention. In this variant, a single actuator can be sufficient to move one of the two flap halves.This movement is transferred to the sealed half of the flap via the driver once the desired release situation has been reached, i.e. after the part of the rotation path to be sealed has been passed.

[0020] A further advantage is achieved when, in a throttle device according to the invention, the flap half to be sealed is the lower flap half of the throttle valve. The lower flap half preferably correlates with a lower valve seat of an intake valve, which can be located at the end of the air supply duct. Further explanation of this will follow later with reference to the air supply system.

[0021] A further subject of the present invention is an air supply system for an internal combustion engine. Such an air supply system is characterized by the provision of at least one throttle device according to the invention. An inlet valve into a combustion chamber of the internal combustion engine is arranged at the end of the air duct downstream of the throttle valve in the flow direction. Accordingly, an air supply system according to the invention provides the same advantages as those explained in detail with reference to the throttle device according to the invention.

[0022] An air supply system according to the invention can be further developed in such a way that the inlet valve has a valve seat that spans a plane at an acute angle to the longitudinal axis of the combustion chamber. The flap half to be sealed borders on the section of the inner wall to which the lower section of the valve seat borders. Top and bottom are defined in particular with reference to a piston that moves along the longitudinal axis and thus along a movement axis within the combustion chamber. In the upper position of the piston, the combustion chamber is particularly small in terms of its volume, and in the lower position it is particularly large. Accordingly, an upper and lower valve seat or an upper and lower section of the valve seat can also be defined.The correlation between the valve half to be sealed and the lower section of the valve seat ensures that, due to the asymmetrical distribution of the air flow in the inventive manner, the air flows through the intake valve primarily through the upper section of the valve seat. Thus, despite a symmetrical design of the intake valve, an asymmetrical inflow into the combustion chamber occurs for the inventive action of the throttle device. This asymmetry of the inflow results in a vortex within the combustion chamber, which, as already described, significantly increases the fuel efficiency of such an internal combustion engine.

[0023] It is also advantageous if, in an air supply system according to the invention, the section of the air duct between the throttle valve and the intake valve has a substantially straight extension. This allows for cost advantages and reduced complexity, particularly with regard to design expenditures. A specially shaped air duct can preferably be dispensed with, since the desired swirl is provided by the throttle device according to the invention.

[0024] Of course, it is also possible for an air supply system according to the invention to have at least a partial curvature in the section of the air duct between the throttle valve and the intake valve. Such a curvature, in the form of a bend in the air duct, increases the asymmetry or swirl inside the combustion chamber. Such a design is particularly advantageous in boxer engines.

[0025] The present invention is explained in more detail with reference to the accompanying drawings. The terms "left," "right," "top," and "bottom" refer to an orientation of the drawings with normally legible reference numerals. They schematically show: Fig. 1 a first embodiment of an air supply system according to the invention, Fig. 2 the embodiment of the Fig. 1 with partially open throttle valve, Fig. 3 the design of the Fig. 1 and Fig. 2 with the throttle fully open, Fig. 4 shows a further embodiment of an air supply system according to the invention, Fig. 5 the embodiment of the Fig. 4 with partially open throttle valve, Fig. 6 the embodiment of the Fig. 4 and Fig. 5 with the throttle fully open, Fig. 7 shows a further embodiment of an air supply system according to the invention, Fig. 8 the embodiment of the Fig. 7 with partially opened throttle valve and Fig. 9 the embodiment of the Fig. 7 and Fig. 8 with the throttle fully open.

[0026] In the Fig. 1 to 3 illustrate a first embodiment of an air supply system 100 according to the invention. This air supply system 100 for an internal combustion engine comprises a throttle device 10. This throttle device 10 is designed with a throttle valve 30 and an air duct 20. The air duct 20 is provided with a substantially rectilinear extension, although curved configurations of the air duct 20 are also conceivable.

[0027] In the design of the Fig. 1 to 3, the throttle device 10 is designed such that a sealing device 40 in the form of a flap wedge 42 is provided. This flap wedge 42 is arranged on the throttle valve 30 on the lower flap half 34. The upper flap half 32 is designed without a sealing device 40. The aforementioned throttle valve 30 is rotatably mounted about a pivot point D in the air duct 20, so that a rotation about this pivot point D of the rotary flap 30 can take place. The individual rotation steps are described, for example, in the following Fig. 2 and Fig. 3 shown.

[0028] The rotation of the throttle valve 30 takes place between a closing position S, as Fig. 1 and an open position O, as shown Fig. 3. The path in between can be called rotation path R and is shown, for example, in Fig. 1. The throttle valve 30, or in this case in particular the lower valve half 34, moves along this path. In particular, the end 34b of the lower valve half 34 moves along the rotation path R.

[0029] This air supply system 100 further includes an inlet valve 110 at the end of the air duct 20. This inlet valve 110 can be sealed by a valve seat 112, thus ensuring the opening and closing of the air supply to the combustion chamber 200. The inlet valve 110 is arranged such that the valve seat 112 defines a plane that is formed at an acute angle to the longitudinal axis L of the combustion chamber 200. This forms a lower section 112a of the valve seat 112 and an upper section 112b of the valve seat 112.

[0030] The operation of this embodiment is briefly explained below. The throttle valve 30 is located in Fig. 1 in the closed position S. If the combustion engine is now started and a partial load or a low load range is desired, the throttle valve moves out of this closed position S along the rotation path R. Over part of the rotation path R, the sealing device 40 acts with the valve wedge 42 in such a way as Fig. 2 shows. This opens a gap between the upper flap half 32 and the inner wall 22 of the air duct 20, while the sealing device 40 in the region of the lower flap half 34 seals this lower flap half 34 against the inner wall 22. An air flow, as shown by the dotted arrow, occurs exclusively or essentially exclusively between the inner wall 22 and the upper flap half 32. Accordingly, this asymmetrical air flow can also flow primarily through the region of the inlet valve 110 into the combustion chamber 200, which is associated with the upper section 112b of the valve seat 112. This creates a vortex in the combustion chamber 200 that rotates essentially counterclockwise.

[0031] If the throttle valve 30 continues to move along the rotation path R until it reaches the open position O, a position as shown in Fig. 3 is reached. In this position, the air flow (dashed arrows) passes both sides of the throttle valve 30, so that an essentially symmetrical inflow via the inlet valve 110 into the combustion chamber 200 takes place and the full or essentially full power is made available.

[0032] The Fig. 4 to 6 show a further embodiment of an air supply system 100 according to the invention. This differs with regard to the embodiment of the Fig. 1 to 3 only by the design of the throttle device 10. Accordingly, with regard to the other components and functions, the design according to the Fig. 1 to 3. In this embodiment of the throttle device 10, a sealing device 40 in the form of a wall wedge 44 is provided. The throttle valve 30 is provided without additional components and moves with the lower valve half 34 along the sealing surface 44a of the wall wedge 44. Thus, as in Fig. 5, even after leaving the closed position S according to Fig. 4 sealing of the lower half of the flap 34 can be carried out, so that an asymmetrical flow around the throttle valve 30 is created, as already described for the Fig. 1 to 3, in particular with regard to Fig. 2 has been explained. Fig. 6 shows the open position O of the throttle valve 30, which in turn preferably correlates with the full load situation of the combustion chamber 200.

[0033] The Fig. 7 to 9 show a further embodiment of an air supply system 100 according to the invention. Here too, there are no distinctions with regard to the combustion chamber and the inlet valve 110, so that reference is also made here to the explanations regarding the Fig. 1 to 3. The sealing device 40 is designed in this embodiment such that the throttle valve 30 has two separately movable valve halves 32 and 34. As part of the sealing device 40, a driver 46 is provided, which drives the lower valve half 34 from a certain opening angle of the upper valve half 32. This situation is in Fig. 8, which correlates, for example, with a partial load range or a low load range during combustion in the combustion chamber 200. Fig. 9 again shows the complete opening of the open position O of the throttle valve 30. The operation and effect of this embodiment is also essentially identical to the embodiment according to the Fig. 1 to 3.

[0034] The above explanation of the embodiments describes the present invention only by way of example. Of course, individual features of the embodiments can be freely combined with one another, provided they are technically feasible, without departing from the scope of the present invention. List of reference symbols 10 Throttle device 20 air duct 22 inner wall 30 Throttle valve 32 upper flap half 34 lower flap half 34a Side of the lower flap half 34b End of the lower flap half 36 Storage 40 Sealing device 42 flap wedge 42a Outer surface of the valve wedge 44 Wall wedge 44a Sealing surface of the wall wedge 46 drivers 100 Air supply system 110 Inlet valve 112 valve seat 112a lower section of the valve seat 112b upper section of the valve seat 200 combustion chamber R rotation path S closing position O Open position L Longitudinal axis of the combustion chamber D Pivot point

Claims

[1] Throttle device (10) for an air supply system (100) of an internal combustion engine, comprising an air duct (20) with an inner wall (22) and a throttle valve (30) with an upper valve half (32) and a lower valve half (34), wherein the throttle valve (30) is rotatably mounted for a rotational path (R) between a closed position (S) and an open position (O) at a pivot point (D) which is arranged between the two valve halves (32, 34) in the air duct (20), wherein a sealing device (40) is provided for sealing one of the two valve halves (34) against the inner wall (22) over a part of the rotational path (R) adjacent to the closed position (S), characterized byin that the sealing device (40) has a wall wedge (44) which is arranged on the inner wall (22) and reduces the cross-section of the air duct (22) along the part of the rotation path (R) to be sealed, wherein the wall wedge (44) has a sealing surface (44a) with a radius of curvature which corresponds to the cross-sectional radius of the air duct (22). [2] Throttle device (10) according to claim 1, characterized by that the sealing device (40) is designed to seal one of the two flap halves (34) over a part of the rotation path (R) of less than 30° adjacent to the closing position (S). [3] Throttle device (10) according to one of the preceding claims, characterized bythat the sealing device (40) has a flap wedge (42) which is arranged on the side (34a) of the flap half (34) to be sealed that faces away from the air flow and has its greatest thickness at the end (34b) of the flap half (34) to be sealed that faces the inner wall (22). [4] Throttle device (10) according to claim 3, characterized by that the flap wedge (42) has a curved outer surface (42a) facing the inner wall (22), which in particular has a radius of curvature which corresponds or substantially corresponds to the cross-sectional radius of the air duct (22). [5] Throttle device (10) according to one of the preceding claims, characterized by that the two flap halves (32, 34) are at least partially movable independently of one another, wherein the sealing device (40) is formed at least in sections by one of the two flap halves (32, 34). [6] Throttle device (10) according to claim 5, characterized by that one of the two flap halves (34) has a driver (46) which strikes against the other flap half (32) from a predefined rotational position of the other flap half (32). [7] Throttle device (10) according to one of the preceding claims, characterized by that the flap half (34) to be sealed is the lower flap half (34) of the throttle valve (30). [8] Air supply system (100) of an internal combustion engine, characterized by that at least one throttle device (10) having the features of one of claims 1 to 7 is provided, wherein an inlet valve (110) in a combustion chamber (200) of the internal combustion engine is arranged at the end of the air duct (20) downstream of the throttle valve (30) in the flow direction. [9] Air supply system (100) according to claim 8, characterized bythat the inlet valve (110) has a valve seat (112) which spans a plane at an acute angle to the longitudinal axis (L) of the combustion chamber (200), wherein the flap half (34) to be sealed adjoins the section of the inner wall (22) to which the lower section (112a) of the valve seat (112) adjoins. [10] Air supply system (100) according to one of claims 8 or 9, characterized by that the section of the air duct (20) between the throttle valve (30) and the inlet valve (440) has a substantially straight extension. [11] Air supply system (10) according to one of claims 8 or 9, characterized by that the section of the air duct (20) between the throttle valve (30) and the inlet valve (110) has at least partially a curvature.

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