Fresh air system for an internal combustion engine

Abstract

A fresh air system for supplying combustion chambers of an internal combustion engine with fresh air may include a housing, through which at least one fresh air path passes, and a flap mechanism, which includes at least one flap adjustably mounted on the housing. The flap may be rotatably adjustable between a closed position, in which the flap closes off the fresh air path in a fluid-tight manner and an opened position, in which the flap opens the fresh air path for fresh air to flow through. The flap mechanism may include a spring-elastic preload element, which supports itself on the housing and preloads the flap against at least one of the opened position and the closed position.

Claims

1. A fresh air system for supplying combustion chambers of an internal combustion engine with fresh air, comprising: a housing, through which at least one fresh air path passes; a flap mechanism including at least one flap and a pivot shaft rotationally adjustably mounted on the housing, the at least one flap being rotatably adjustable between a closed position, in which the at least one flap closes off the fresh air path in a fluid-tight manner and an opened position, in which the at least one flap opens the fresh air path for fresh air to flow through; and a recess provided on at least one of the pivot shaft and the at least one flap, the recess disposed in a fixed location relative to the at least one of the pivot shaft and the at least one flap; wherein the flap mechanism includes a spring-elastic preload element, the spring-elastic preload element having a first end portion supported on the housing and a second end portion arranged to preload the at least one flap against the opened position or the closed position, and wherein the second end portion is received in the recess.

2. The fresh air system according to claim 1, wherein at least two fresh air paths are provided and the flap mechanism includes at least two flaps associated with a corresponding one of the at least two fresh air paths, in each of which a flap is provided, and wherein the at least two flaps are each attached to the pivot shaft in a rotationally fixed manner.

3. The fresh air system according to claim 1, wherein the spring-elastic preload element is a leaf spring or a coil spring.

4. The fresh air system according to claim 1, wherein the housing includes a pocket-like support region, the pocket-like support region supporting the first end portion of the spring-elastic preload element.

5. The fresh air system according to claim 1, wherein the spring-elastic preload element is arranged between the housing and the at least one of the pivot shaft and the at least one flap such that the spring-elastic preload element acts as a tension spring and a compression spring.

6. The fresh air system according to claim 1, further comprising a holding element arranged rotationally fixed on at least one of the pivot shaft and the at least one flap, the holding element having a substantially hollow-cylindrical structure and including an extension projecting radially with respect to the pivot shaft, wherein the recess receiving the second end portion of the spring-elastic preload element is arranged on the extension.

7. The fresh air system according to claim 1, wherein: the preload element is formed as a leaf spring, and at least the first end portion of the leaf spring is curved.

8. The fresh air system according to claim 1, wherein the flap mechanism further includes an electrically driven actuator arranged drive-connected with the pivot shaft, and wherein the at least one flap via the actuator is pivot-adjustable between the opened position and the closed position.

9. An internal combustion engine, comprising: at least one combustion chamber, a fresh air system fluidically connected to the combustion chamber, the fresh air system including: a housing through which at least one fresh air path passes; and a flap mechanism including at least one flap rotation-adjustably mounted on the housing via a pivot shaft, a recess disposed on at least one of the pivot shaft and the at least one flap, the at least one flap being rotatably adjustable between (i) a closed position, in which the at least one flap closes off the fresh air path in a fluid-tight manner, and (ii) an open position, in which the at least one flap opens the fresh air path for fresh air to flow through; wherein the flap mechanism includes a spring-elastic preload element structured as a leaf spring or a coil spring, the spring-elastic preload element supporting itself on the housing and preloads the flap against at least one of the opened position and the closed position; wherein the spring-elastic preload element includes a first end portion supported on the housing and a second end portion supported in the recess disposed on the at least one of the pivot shaft and the at least one flap for preloading the at least one flap.

10. The internal combustion engine according to claim 9, wherein at least four fresh air paths are provided and each path includes an associated flap, and wherein the respective flaps are attached to the pivot shaft.

11. The internal combustion engine according to claim 9, wherein the housing includes a pocket-shaped support region for supporting the first end portion of the preload element.

12. The internal combustion engine according to claim 9, wherein the preload element is arranged between the housing and at least one of the pivot shaft and the at least one flap such that the preload element acts as a tension spring and a compression spring.

13. The internal combustion engine according to claim 9, wherein the preload element is structured as the coil spring and the first end portion is arranged opposite to the second end portion.

14. The internal combustion engine according to claim 13, wherein the preload element is formed as a leaf spring, and wherein at least the first end portion is curved.

15. The internal combustion engine according to claim 9, further comprising a holding element coupled to at least one of the pivot shaft and the at least one flap, wherein the holding element includes a radially projecting extension and the recess is arranged in the extension, wherein the second end portion of the preload element is received in the recess.

16. The internal combustion engine according to claim 9, wherein the flap mechanism includes an electrical actuator drive-connected with the pivot shaft, wherein the actuator pivotally adjust the at least one flap between the opened position and the closed position.

17. A fresh air system for supplying fresh air to an internal combustion engine, comprising: a housing through which at least one fresh air path extends; a flap mechanism including at least one flap rotation-adjustably mounted on the housing via a pivot shaft, the at least one flap being rotatably adjustable between (i) a closed position, in which the at least one flap closes off the fresh air path in a fluid-tight manner, and (ii) an open position, in which the at least one flap opens the fresh air path for fresh air to flow through; a holding element coupled to at least one of the pivot shaft and the at least one flap, the holding element having a hollow-cylindrical structure and including a radially projecting extension, the extension provided with a recess; and an electrical actuator drive-connected with the pivot shaft to pivotally adjust the at least one flap between the opened position and the closed position; wherein the flap mechanism includes a spring-elastic preload element to preload the at least one flap against one of the open position and the closed position, the spring-elastic preload element having a first end portion supported on the housing and a second end portion received within the recess arranged in the extension.

18. The fresh air system according to claim 17, wherein the housing includes a pocket-shaped support region, and wherein the first end portion of the spring-elastic preload element is arranged in the pocket-shaped support region of the housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) It shows, in each case schematically

(2) FIG. 1a/b part views each of a fresh air system according to the invention,

(3) FIG. 2 a flap mechanism of the fresh air system with four flaps,

(4) FIG. 3a/b examples of a preload element formed as a leaf spring,

(5) FIG. 4/5 the flap mechanism without/with a leaf spring mounted on the pivot shaft, in each case in a cross section,

(6) FIG. 6 a schematic representation of the flap mechanism as part of a tension spring arrangement,

(7) FIG. 7 a schematic representation of the flap mechanism as part of a compression spring arrangement.

DETAILED DESCRIPTION

(8) FIGS. 1a and 1b illustrate a part view of a fresh air system 1 according to the invention, which shows the flap mechanism 3 arranged in an adequately dimensioned housing 2 of the fresh air system 1. FIG. 2 shows said flap mechanism 3 in a separate representation. The same comprises in the example scenario of FIG. 2 four flaps 5 fastened on a common pivot shaft 4 in a rotationally fixed manner (the flaps 5 are not shown in the representation of FIGS. 1a and 1b).

(9) The four flaps 5 are each arranged in a fresh air path (not shown) of the fresh air system 1, so that the four fresh air paths are closed off in a fluid-tight manner by the flaps 5 by rotating the pivot shaft 4, which is mounted on the housing 2 in a rotatably adjustable manner, into a closed position of the flaps 5. In an opened position by contrast the flaps 5 open the fresh air paths for fresh air to flow through so that it can be admitted into combustion chambers fluidically connected downstream of the fresh air system 1. Obviously, the flaps 5 can also be positioned in an intermediate position between said opened and closed position.

(10) The flap mechanism 3 is now equipped with a spring-elastic preload element 6 in the form of a leaf spring 7 which supports itself on the housing 2, preloading the flaps 5 either against their opened or the closed position. FIG. 1a shows the leaf spring 7 in a position which is assigned to an opened position of the flaps 5, while FIG. 1b by contrast shows leaf spring 7 in a position which corresponds to closed position of the flaps 5.

(11) FIGS. 3a and 3b show rough schematic examples of possible geometrical designs of the leaf spring 7 which for example can be formed as a flat metal strip. Such a leaf spring 7 comprises a first end portion 8 for supporting on the housing 2 of the fresh air system 1 and a second end portion 9 for supporting on the pivot shaft 4.

(12) In the example of FIG. 3a, the first end portion 8 of the leaf spring 7 is designed curved. Such a quality of the leaf spring allows keeping the installation space required for installing the leaf spring 7 in the housing 2 of the fresh air system 1 relatively small. A curved design of the leaf spring 7 however is not limited to its first end portion 8 only: in the example of FIG. 3b for example the entire leaf spring 7 except for the second end portion 9 is designed curved.

(13) In order to now keep the installation space required for fastening the leaf spring 7 on the housing as small as possible it is advisable to form a support region 10 designed pocket-like on the housing 2, which is schematically shown in the FIGS. 1a/1b. On the housing walls of such a pocket the first end portion 8 of the leaf spring 7 can then support itself.

(14) Mechanically stable fastening of the preload element 8 formed as a leaf spring 7 in the exemplary scenario canalso in the event that another spring 5, for example an already mentioned coil spring is usedbe achieved in that on the pivot shaft 4 a holding element 14 is provided, in which the recess 11 is arranged. As shown in the figures, the holding element 14 can be designed as a separate component and be fastened to the pivot shaft 4 in a rotationally fixed manner. Alternatively to this however it is also conceivable to integrally mould the holding element 14 on the pivot shaft 4 (not shown). In a further version the recess 11 can also be provided directly on the pivot shaft 4 (not shown).

(15) In a further version of the example, which in FIG. 2 is exemplarily shown only for a single flap 5 in dashed representation for the sake of clarity, the preload element 6, for example in the form of the already mentioned leaf spring 7, can also support itself on the flap 5. For this purpose, a recess 11 which was already discussed above in connection with the pivot shaft 4 can also be provided on the flap 5. Analogously to the above example, the recess 11 can be directly provided in the flap 5 or as shown in dashed representation in FIG. 2 be provided in a holding element 14, which is explained above in connection with the pivot shaft 4 and shown in the FIGS. 1a and 1b. If the recess 11be it directly or indirectly in said holding element 14is provided in the flap 5, it proves to be advantageous to arrange the recess in the region of the flap 5 in which the same or the pivot shaft 4 is mounted on the housing 2. This region is exemplarily marked in FIG. 2 for a single flap 5 with the reference number 15.

(16) In all cases, the second end portion 9 of the leaf spring 7 can be inserted in the recess 11 for supporting on the pivot shaft 4 or on the flap 5. In order to be able to provide the recess 11 with a particularly large recess depth for the stable fixing of the leaf spring 7, an extension 12 is provided on the holding element 14 of substantially hollow-cylindrical form, in which in turn said recess 11 is arranged.

(17) For illustration, FIG. 5 shows the flap mechanism 3 with leaf spring 7 inserted in the recess 11. For durably fixing the leaf spring 7 in the recess 11 the person skilled in the art has a plurality of options, conceivable for example are fastening by means of screwing, clipping or injection overmoulding. Simple inserting of the second end portion 9 into the recess 11 is also easily conceivable.

(18) Depending on the manner in which the preload element 6 is arranged between pivot shaft 4 and housing 2 a tension spring arrangement (schematically shown in FIG. 6) or compression spring arrangement (schematically shown in FIG. 7) can prove to be as a particularly advantageous form of realisation in terms of design. In the case of the tension spring arrangement shown in FIG. 6 the preload element 6 is subjected to tensile loading starting out from a starting position shown in FIG. 6 by rotating the pivot shaft 4 or the flap 5 in the direction of rotation D and transferred into a state which is elongated with respect to the starting position. In the case of the compression spring arrangement shown in FIG. 7, a pivot movement of the pivot shaft 4 in pivot direction D by contrast results in a compression of the preload element 6, so that the same is subjected to compression loading. In both cases, the preload force generated by the preload element 6 and acting on the pivot shaft 4 or the flap 5 is increased. Depending on the installation situation in the fresh air system 1, realisation as tension or compression spring arrangement can prove to be advantageous.

(19) For the control movement of the pivot shaft 4 and the at least one flap 5 attached thereon the flap mechanism 3 is preferably equipped with an in particular electrically driven actuator that is drive-connected to the pivot shaft 4, which actuator is roughly schematically shown in FIG. 2 and marked with the reference number 13.