Air control device with bearing point

Abstract

Bearing point (11) for the rotatable mounting of a shaft (8) on a support structure (13) about an axis of rotation (7), - with a bearing opening (14) formed in the supporting structure (13), into which the shaft (8) projects or through which the shaft (8) projects, - with an annular seal (15) arranged coaxially to the axis of rotation (7) for sealing the bearing opening (14) - wherein the bearing opening (14) has a cylindrical inner bearing surface (30) arranged coaxially to the axis of rotation (7) on its inner circumference, - wherein the shaft (8) has a cylindrical outer bearing surface (31) arranged coaxially to the axis of rotation (7) on its outer circumference, - wherein the outer storage area (31) is in full contact with the inner storage area (30), - wherein the seal (15) is designed as a labyrinth seal, which has at least one annular rib (16) and at least one annular groove (17) into which the rib (16) projects axially, - wherein an inner sealing gap (18) and an outer sealing gap (19) are formed radially between two outwardly facing outer walls (20, 22) of the rib (16) and two mutually facing inner walls (21, 23) of the groove (17), each of which is annular in shape and arranged coaxially to the axis of rotation (7), characterized in that - that an internal radial clearance (24) of the internal sealing gap (18) between the inner wall (21) of the respective groove (17) and the outer wall (20) of the respective rib (16) is smaller than an axial distance (26) between a groove base (27) and an end wall (28) of the rib (16), and / or - that an external radial clearance (25) of the external sealing gap (19) between the inner wall (23) of the respective groove (17) and the outer wall (22) of the respective rib (16) is smaller than an axial distance (26) between a groove base (27) and an end wall (28) of the rib (16).

Description

[0001] The present invention relates to a bearing for rotatably mounting a shaft on a support structure about an axis of rotation, comprising the features of the preamble of claim 1. The invention further relates to an air control device for an air conditioning system equipped with such a bearing, comprising the features of the preamble of claim 6. The present invention further relates to an air conditioning system for a vehicle for climate-controlling a vehicle interior, which is equipped with such an air control device.

[0002] From EP 0 925 969 B1, an air control device for an air conditioning system is known, comprising a housing for forming at least one duct for guiding an airflow and at least one flap for controlling the airflow in the duct, wherein the flap is rotatably arranged in the housing about a pivot axis for opening and closing the duct. The flap has a shaft from which at least one blade projects. The shaft is rotatably mounted about the pivot axis at at least one of its longitudinal ends by means of a bearing on a wall of the housing, which serves as a support structure. The bearing formed here includes a bearing opening in the support structure through which the shaft projects. Furthermore, the bearing is equipped with an annular seal arranged coaxially to the pivot axis for sealing the bearing opening.In the known bearing arrangement, the seal is formed by an annular sealing gap arranged coaxially to the axis of rotation. This gap is radially formed between a cylindrical inner wall, fixed to the shaft and arranged annularly, circumferentially, and a cylindrical outer wall, arranged on the supporting structure. Furthermore, the bearing opening of the bearing arrangement has a cylindrical inner bearing surface arranged coaxially to the axis of rotation on its inner circumference, while the shaft has a cylindrical outer bearing surface arranged coaxially to the axis of rotation on its outer circumference, which bears against the inner bearing surface in a flat manner. In the known bearing arrangement, the seal is axially spaced from an axial section of the shaft in which the outer bearing surface interacts with the inner bearing surface to support the shaft.

[0003] Other air control devices with bearing points are known from US 2008 / 0 176 502 A1, AT 149 893 B, DE 671 566 A, DE 698 33 474 T2, DE 11 2012 002 939 T5, DE 691 00 274 ​​T2, WO 2006 / 037567 A1, EP 2 072 297 A1 and DE 10 2007 026 620 B4.

[0004] The present invention addresses the problem of providing an improved embodiment for a bearing of the type mentioned above or for an air control device equipped with at least one such bearing, which is characterized in particular by increased sealing in the area of ​​the bearing. Furthermore, an axially compact design in the area of ​​the bearing is desired.

[0005] According to the invention, this problem is solved by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0006] The invention is based on the general concept of designing the seal as a labyrinth seal, wherein the labyrinth seal comprises at least one annular rib and at least one annular groove, the respective rib projecting axially into the respective groove. Each rib has two outer walls that face away from each other in the radial direction and each form a closed ring around the circumference, preferably being cylindrical. The groove, in turn, has two inner walls that face each other radially and also form a closed ring around the circumference, preferably being cylindrical.The respective rib and groove are aligned with each other in terms of their radial dimensions such that the inner wall, located inwards relative to the axis of rotation, forms an inner sealing gap with the outer wall, also located inwards relative to the axis of rotation, while simultaneously the inner wall, located outwards relative to the axis of rotation, forms an outer sealing gap with the outer wall, also located outwards relative to the axis of rotation. The respective sealing gap extends in an annular shape and is coaxial with the axis of rotation. Furthermore, the respective sealing gap is formed radially between the corresponding inner wall and the corresponding outer wall and extends in the axial direction, depending on the axial overlap between the rib and the groove.

[0007] By using a labyrinth seal with at least two concentric sealing gaps, the effectiveness of the shaft seal against the supporting structure can be significantly improved. A further advantage is that such a labyrinth seal operates virtually maintenance-free. In particular, lubrication is unnecessary.

[0008] According to the invention, the internal radial clearance between the inner wall of the respective groove (located inwards with respect to the axis of rotation) and the outer wall of the respective rib (located inwards with respect to the axis of rotation) is smaller than the axial distance between the groove base and the end wall of the rib. Additionally or alternatively, the external radial clearance between the inner wall of the respective groove (located outwards with respect to the axis of rotation) and the outer wall of the respective rib (located outwards with respect to the axis of rotation) can be smaller than the axial distance between the groove base and the end wall of the rib. These relationships exist at least at ambient temperature. These relationships enable a simple design of the labyrinth seal, since precise axial positioning between the shaft and the supporting structure is not required to achieve the desired sealing effect.This requires only a near-coaxial positioning of the shaft within the bearing opening, so that each rib can engage axially in its respective groove to form the two radial sealing gaps. The radial clearance for each sealing gap is smaller, preferably at least 10 times smaller, than the rib or groove width measured in the radial direction.

[0009] According to another advantageous embodiment, the respective rib can engage axially in the respective groove in an axial section of the shaft, with the outer bearing surface interacting radially with the inner bearing surface to rotatably mount the shaft on the support structure. Thus, the labyrinth seal is located immediately radially adjacent to the bearing opening, resulting in a comparatively compact bearing design in the axial direction and consequently requiring little installation space.

[0010] In another advantageous embodiment, at least one such rib can be formed on the shaft, in particular on an annular step of the shaft, and is then expediently arranged radially spaced from the outer bearing surface. The corresponding groove is then formed on the support structure and arranged radially spaced from the bearing opening. This also results in an extremely compact design in the axial direction for the respective bearing location.

[0011] An air control device according to the invention is characterized in that at least one flap for controlling an airflow has a shaft which is rotatably mounted about an axis of rotation on a wall of the housing serving as a support structure, with at least one bearing point of the type described above. This also improves the sealing of the air control device in the area of ​​the bearing points.

[0012] According to an advantageous embodiment, the respective flap can have at least two wings that project from the shaft at different circumferential sections. A flap with exactly two wings can also be called a butterfly flap. Such a flap is particularly characterized by the fact that only comparatively low torques are required to adjust the flap.

[0013] According to an advantageous embodiment, at least two flaps can be of different sizes radially to the axis of rotation. This makes the flap asymmetrical, which is advantageous for certain applications. In particular, this makes it easier to position the shaft in an edge region of the respective channel.

[0014] In another advantageous embodiment, the flap may have exactly two wings that enclose a wing angle other than 180° in the circumferential direction. This design also supports complex installation situations, particularly in conjunction with an eccentric arrangement of the flap relative to the duct.

[0015] In another advantageous embodiment, the shaft can be arranged at a distance from a longitudinal center axis of the channel. This results in reduced flow resistance for the flap when it is open.

[0016] In another advantageous embodiment, at least one such flap in the housing can serve to adjust the mixing ratio between recirculated air and fresh air. Additionally or alternatively, at least one such flap can serve to adjust the mixing ratio between warm air and cold air. Additionally or alternatively, at least one such flap in the housing can serve to adjust the volume flow rate for the airflow in the respective duct. Thus, each flap within the housing performs different functions.

[0017] An air conditioning system according to the invention, which serves to air-condition a vehicle interior in a vehicle, is equipped with an air control device of the type described above.

[0018] Further important features and advantages of the invention will become apparent from the dependent claims, the drawings and the associated description of the figures based on the drawings.

[0019] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0020] Preferred embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein identical reference numerals refer to identical or similar or functionally identical components.

[0021] They show, schematically, Fig. 1 A highly simplified sectional view of an air conditioning system in the area of ​​an air control device, Fig. 2 an isometric view of a flap in the area of ​​a bearing point, Fig. 3 an isometric view of a housing of the air control device in the area of ​​the bearing point, Fig. 4 a sectional view of the storage site, Fig. 5 an enlarged detail IV from Fig. 4.

[0022] Accordingly Fig. 1 comprises an air conditioning system 1, with the aid of which a vehicle interior of a vehicle, preferably a road vehicle, can be air-conditioned, and at least one air control device 2. The air control device 2 has a housing 3, which is shown here open and which serves to form at least one channel 4, which in turn serves to guide an airflow 5, indicated by an arrow. The air control device 2 is further equipped with at least one flap 6, which serves to control the airflow 5 in the channel 4 and which is rotatably arranged in the housing 3 about a pivot axis 7. Depending on its rotational position, the flap 6 can open and close the channel 4. Furthermore, any number of intermediate positions between the open position and the closed position are generally possible.

[0023] The flap 6 has a wave 8, from which at least one wing 9 projects. In the example of the Fig. Two wings 9 extend from the shaft 8. The shaft 8 is rotatably mounted on the housing 3 about the axis of rotation 7 at at least one of its longitudinal ends 10 by means of a bearing 11. The bearing 11 is formed in a wall 12 of the housing 3, which serves as a support structure 13 for this purpose. Advantageously, the flap 6 is mounted on the housing 3 at both longitudinal ends 10 of the shaft 8 by means of such a bearing 11.

[0024] According to the Fig. 2 to 5 each comprise a bearing point 11, which serves to rotatably support the shaft 8 on the support structure 13 about the axis of rotation 7, and a bearing opening 14 formed in the support structure 13. As mentioned, the support structure 13 is formed here by a section of the wall 12 of the housing 3. In the assembled state, which is in the Fig. 4 and Fig. As shown in Figure 5, the shaft 8 projects axially into the bearing opening 14 and ends within the bearing opening 14. However, an embodiment in which the shaft 8 extends through the bearing opening 14 is also conceivable.

[0025] The bearing 11 is also equipped with a labyrinth seal 15, which is arranged coaxially to the axis of rotation 7, extends in an annular shape, and serves to seal the bearing opening 14. For this purpose, the labyrinth seal 15 has at least one annular rib 16 and at least one annular groove 17. In the assembled state, the rib 16 engages axially in the groove 17. The axial direction is defined by the longitudinal direction of the axis of rotation 7. In the example shown here, the labyrinth seal 15 has only one rib 16 and only one groove 17. In other embodiments, several ribs 16 with several complementary grooves 17 can also be provided. Furthermore, in this example, the rib 16 is formed on the shaft 8, in particular, it is formed integrally with it. In contrast, the groove 17 is formed in the support structure 13.In principle, however, a reverse design is also conceivable, in which the groove 17 is formed on the shaft 8, while the rib 16 is located on the support structure 13. The embodiment shown here, in which the rib 16 is located on the shaft 8, is particularly compact.

[0026] The labyrinth seal 15 is characterized in the assembled state of the bearing point 11 according to the Fig. 4 and Fig. 5 is formed by two sealing gaps, namely an inner sealing gap 18, which is arranged inside with respect to the axis of rotation 7, and an outer sealing gap 19, which is arranged outside with respect to the axis of rotation 7. The two sealing gaps 18, 19 are arranged coaxially to each other and coaxially to the axis of rotation 7, with the inner sealing gap 18 extending within the radius of the outer sealing gap 19. The inner sealing gap 18 is according to Fig. The outer sealing gap 19 is formed radially between an outer wall 20 of the rib 16, arranged inwards with respect to the axis of rotation 7, and an inner wall 21 of the groove 17, also arranged inwards with respect to the axis of rotation 7. The outer sealing gap 19, on the other hand, is formed radially between an outer wall 22 of the rib 16, arranged outwards with respect to the axis of rotation 7, and an inner wall 23 of the groove 17, also arranged outwards with respect to the axis of rotation 7. The radial direction refers to the axis of rotation 7, to which it is perpendicular.

[0027] In the area of ​​axial overlap between rib 16 and groove 17, which corresponds to the axial penetration depth of rib 16 into groove 17, the sealing gaps 18, 19 extend axially, giving each sealing gap 18, 19 a corresponding axial gap length. The greater this axial gap length, the more effectively the respective sealing gap 18, 19 seals. Furthermore, radial play within each sealing gap 18, 19 also contributes to the sealing effect. The inner sealing gap 18 has an inner radial play 24, while the outer sealing gap 19 has an outer radial play 25. The inner radial clearance 24 is radially located between the inner wall 21 and the outer wall 20 and is expediently smaller than an axial distance 26 that exists between a groove base 27 of the groove 17 and an axial end wall 28 of the rib 16.The outer radial clearance 25 is located radially between the outer wall 22 and the inner wall 23 and is also smaller than the axial distance 26. The smaller the radial clearance 24, 25, the greater the sealing effect. In this example, the respective radial clearance 24, 25 is significantly smaller, e.g., at least 20 times smaller, than a radially measured width 36 of the rib 16 or a radially measured width 37 of the groove 17.

[0028] How in particular the Fig. 4 and Fig. As can be seen from Figure 5, the labyrinth seal 15 is formed in an axial section 29 of the shaft 8, in which the shaft 8 engages in the bearing opening 14 and in which the shaft 8 is supported on the support structure 13. For this purpose, the bearing opening 14 has a cylindrical inner bearing surface 30 arranged coaxially to the axis of rotation 7 on its inner circumference, while the shaft 8 has a cylindrical outer bearing surface 31 arranged coaxially to the axis of rotation 7 on its outer circumference. The outer bearing surface 31 bears directly and radially against the inner bearing surface 30. The interaction of the inner bearing surface 30 with the outer bearing surface 31 for the rotatable bearing of the shaft 8 on the support structure 13 takes place in the aforementioned axial section 29, in which the labyrinth seal 15 is also arranged, but radially offset from the bearing surfaces 30, 31. In particular, the engagement of the rib 16 in the associated groove 17 takes place in the aforementioned axial section 29, but radially offset from the bearing opening 14.To form the rib 16, the shaft 8 can be equipped with an annular step 32. The rib 16 is arranged radially spaced from the outer bearing surface 31 on the shaft 8. The groove 17 is arranged radially spaced from the bearing opening 14 on the support structure 13.

[0029] In the example of the Fig. 4 and Fig. 5 is a radial distance 38 between the outer bearing surface 31 and the inner outer wall 20 of the rib 16 approximately equal to the radial distance between the two outer walls 20, 22 of the rib 16, which corresponds to the rib width 36.

[0030] How in particular the Fig. 1 and Fig. As can be seen from Figure 2, the flap 6 in the example has exactly two wings 9, which project from the shaft 8 at different circumferential sections. In the case of the Fig. In the embodiment shown in Figure 2, the two wings 9 are of different sizes in the radial direction with respect to the axis of rotation 7. Fig. 2. The left wing 9 has a significantly larger dimension in the radial direction than the right wing 9. Furthermore, the flaps 6 of the Fig. 1 and Fig. 2 provided that the two wings 9 enclose a wing angle 33 in the circumferential direction which is different from 180°.

[0031] At the in Fig. In the embodiment shown in Figure 1, the shaft 8 is arranged in the channel 4 in the region of a longitudinal center axis 34. In contrast, Figure 1 shows... Fig. 3 An embodiment in which the shaft 8 or the axis of rotation 7 is arranged at a distance from the longitudinal center axis 34 of the channel 4. This results in an eccentric or off-center arrangement for the respective flap 6 with respect to the channel 4.

[0032] In housing 3, the respective flap 6 serves, for example, to adjust the mixing ratio between recirculated air and fresh air. Similarly, such a flap 6 in housing 3 can serve to adjust the mixing ratio between warm air and cold air. Furthermore, such a flap 6 in housing 3 can serve to adjust the volume flow for the airflow 5.

[0033] How to Fig. 1, Fig. 2, Fig. 4 and Fig.As can be seen from Figure 5, the shaft 8 is configured as a hollow shaft, at least in the region of its respective longitudinal end 10, so that it has an opening 35 open at its end face. The opening 35 serves advantageously for the axial insertion of a drive element, which is not shown here. By shaping the inner circumference of the opening 35 in a non-circular shape, torque transmission between the respective drive element and the shaft 8 can be achieved. The respective drive element can engage with the shaft 8, in particular through the bearing opening 14. Thus, the torque transmission takes place at the bearing point 11, which is advantageous for the mechanical load on the flap 6.

Claims

[1] Bearing point (11) for the rotatable mounting of a shaft (8) on a support structure (13) about a rotation axis (7), - with a bearing opening (14) formed in the support structure (13) into which the shaft (8) projects or through which the shaft (8) projects, - with an annular seal (15) arranged coaxially to the axis of rotation (7) for sealing the bearing opening (14) - wherein the bearing opening (14) has on its inner circumference a cylindrical inner bearing surface (30) arranged coaxially to the axis of rotation (7), - wherein the shaft (8) has on its outer circumference a cylindrical outer bearing surface (31) arranged coaxially to the axis of rotation (7), - wherein the outer bearing surface (31) lies flat against the inner bearing surface (30), - wherein the seal (15) is designed as a labyrinth seal having at least one annular rib (16) and at least one annular groove (17) into which the rib (16) projects axially, - wherein an inner sealing gap (18) and an outer sealing gap (19) are formed radially between two mutually remote outer walls (20, 22) of the rib (16) and two mutually facing inner walls (21, 23) of the groove (17), each of which is annular and arranged coaxially to the axis of rotation (7), characterized by , - that an inner radial play (24) of the inner sealing gap (18) between the inner wall (21) of the respective groove (17) and the outer wall (20) of the respective rib (16) is smaller than an axial distance (26) between a groove base (27) and an end wall (28) of the rib (16), and / or - that an outer radial play (25) of the outer sealing gap (19) between the inner wall (23) of the respective groove (17) and the outer wall (22) of the respective rib (16) is smaller than an axial distance (26) between a groove base (27) and an end wall (28) of the rib (16). [2] Bearing point (11) according to claim 1, characterized by that the respective rib (16) engages axially in the respective groove (17) in an axial section (29) of the shaft (8), in which the outer bearing surface (31) cooperates radially with the inner bearing surface (30). [3] Bearing point (11) according to claim 1 or 2, characterized by , - that at least one such rib (16) is formed on the shaft (8), - that at least one such groove (17) is formed on the support structure (13). [4] Air control device (2) for an air conditioning system (1) - with a housing (3) for forming at least one channel (4) for guiding an air flow (5), - with at least one flap (6) for controlling the air flow (5) in the duct (4), which is arranged in the housing (3) so as to be rotatable about an axis of rotation (7) for opening and closing the duct (4), - wherein the flap (6) has a shaft (8) from which at least one wing (9) protrudes, - wherein the shaft (8) is rotatably mounted at at least one of its longitudinal ends (10) by means of a bearing point (11) on a wall (12) of the housing (3) serving as a supporting structure (13) about the axis of rotation (7), characterized by that the bearing point (11) is designed according to one of claims 1 to 3. [5] Air control device (2) according to claim 4, characterized by that the flap (6) has at least two wings (9) which protrude from the shaft (8) at different circumferential sections thereof. [6] Air control device (2) according to claim 5, characterized by that the wings (9) are of different sizes radially to the axis of rotation (7). [7] Air control device (2) according to claim 5 or 6, characterized by that the flap (6) has exactly two wings (9) which enclose a wing angle (33) in the circumferential direction which is different from 180°. [8] Air control device (2) according to one of claims 4 to 7 characterized by that the shaft (8) is arranged in the channel (4) at a distance from a longitudinal central axis (34) of the channel (4). [9] Air control device (2) according to one of claims 4 to 8, characterized by that at least one such flap (6) in the housing (3) serves to adjust a mixing ratio between recirculated air and fresh air. [10] Air control device (2) according to one of claims 4 to 9, characterized by that at least one such flap (6) in the housing (3) serves to adjust a mixing ratio between warm air and cold air. [11] Air control device (2) according to one of claims 4 to 10, characterized bythat at least one such flap (6) in the housing (3) serves to adjust a volume flow of the air flow (5) in the respective duct (4). [12] Air conditioning system (1) for a vehicle for air conditioning a vehicle interior, with at least one air control device (2) according to one of claims 6 to 11.

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