DEVICE FOR TRANSMITTING COMPRESSED AIR OR CONTROL AND/OR WORKING PRESSURES IN A CARDAN SHAFT ARRANGEMENT

Abstract

A rotation transmission apparatus for transmitting control and/or working pressures to a fluid channel, which is at least regionally configured or accommodated on or in a shaft, in particular a drive shaft, wherein the rotation transmission apparatus includes a stator assembly, which is arranged such that it is stationary relative to a rotational movement of the shaft and has at least one fluid supply/discharge line, wherein the fluid supply/discharge opens into an annular space which surrounds the shaft at least partially and with which the fluid channel of the shaft is fluidically connected via a branch channel, wherein the annular space is associated with sealing elements, which are arranged and configured in the annular space at least partially such that they seal the annular space from the outside atmosphere when a previously defined or definable overpressure is applied in the annular space.

Claims

1. A rotation transmission apparatus (1) for transmitting control and/or working pressures to a fluid channel (3), which is at least regionally configured or accommodated on or in a shaft (2), wherein the rotation transmission apparatus (1) comprises: a stator assembly (4) which is arranged such that it is stationary relative to a rotational movement of the shaft (2) and has at least one fluid supply/discharge line (5), wherein the fluid supply/discharge (5) opens into an annular space (6) which surrounds the shaft (2) at least partially and with which the fluid channel (3) of the shaft (2) is fluidically connected via a branch channel, wherein the annular space (6) has associated sealing elements (7) which are arranged and configured in the annular space (6) at least partially such that they seal the annular space (6) from the outside atmosphere when a previously defined or definable overpressure is applied in the annular space (6).

2. The rotation transmission apparatus (1) according to claim 1, wherein the sealing elements (7) comprise at least one radial shaft sealing ring having a radially arranged sealing lip or sealing disc, for sealing the annular space (6) as needed.

3. The rotation transmission apparatus (1) according to claim 2, wherein the at least one radial shaft sealing ring (7) comprises an outer region (9) facing the stator assembly (4) and an inner region (10) facing the shaft (2), wherein the radial shaft sealing ring (7) is preferably exchangeable via its outer region (9) and is connected to the stator assembly (4) via a clamping connection.

4. The rotation transmission apparatus (1) according to claim 3, wherein the inner region (10) of the radial shaft sealing ring (7) facing the shaft (2) is configured at least regionally as a sealing lip or sealing disc which extends radially around the shaft (2) and bears or can be made to bear against a sealing sleeve (11) fastened to the shaft (2).

5. The rotation transmission apparatus (1) according to claim 4, wherein the sealing sleeve (11) has a sealing geometry (12), wherein the sealing geometry (12) comprises at least one region which extends radially around the shaft (2) and projects or protrudes in the direction of the annular space (6).

6. The rotation transmission apparatus (1) according to claim 4, wherein the sealing lip or sealing disc (10) is implemented and/or arranged in the annular space (6) such that, when the annular space (6) is unpressurized, it has no contact to the sealing geometry (12) of the sealing sleeve (11) or only bears against the sealing geometry (12) of the sealing sleeve (11) of the shall (2) so lightly that, upon rotation of the shall (2) relative to the stator assembly (4), the sealing sleeve (11) can slide over the sealing lip or sealing disc (10) without resistance or at least substantially without resistance.

7. The rotation transmission apparatus (1) according to claim 4, wherein the sealing lip or sealing disc (10) is implemented and/or arranged in the annular space (6) such that, when overpressure is applied in the annular space (6), it bears against the sealing geometry (12) of the sealing sleeve (11) of the shaft (2) in a sealing manner.

8. The rotation transmission apparatus (1) according to claim 4, wherein the sealing lip or sealing disc (10) is configured such that it returns to its at least substantially contact-free state when a previously set overpressure in the annular space (6) is released again.

9. The rotation transmission apparatus (1) according to claim 4, wherein the sealing sleeve (11) is pushed onto the shaft (2) and is preferably releasably connected to the shaft (2) in the region of the stator assembly (4), wherein sealing elements (17), in the form of at least one O-ring, are preferably provided for sealing the connection between the sealing sleeve (11) and the shaft (2).

10. The rotation transmission apparatus (1) according to claim 1, wherein a rolling bearing assembly (14) is provided, via which the shaft (2) is fastened such that it can rotate relative to the stator assembly (4).

11. The rotation transmission apparatus (1) according to claim 1, wherein the stator assembly (4) comprises a housing (13) which at least partially surrounds the shaft (2) and in which the rolling bearing assembly (14) is at least regionally accommodated.

12. The rotation transmission apparatus (1) according to claim 1, wherein the stator assembly (4) comprises a clamping ring or fastening assembly (15) for releasably or exchangeably fastening the sealing elements (7) to the stator assembly (4).

13. The rotation transmission apparatus (1) according to claim 12, wherein sealing elements (16), in the form of at least one O-ring, are associated with the clamping ring or fastening assembly (15) for sealing the fastening region of the sealing elements (7).

14. A system having a rotation transmission apparatus (1) according to claim 1 and a shaft (2) on which the rotation transmission apparatus (1) is fastened, wherein the shaft (2) is embodied as a drive shaft of a vehicle.

15. A tire pressure adjustment system for at least one wheel of a wheeled vehicle, driven rotationally relative to a vehicle body, having pneumatic tires and comprising at least one drive shall for driving the wheel, wherein a fluid channel (3) is accommodated or configured inside the drive shaft, and wherein at least one rotation transmission apparatus (1) according to claim 1 is provided for supplying and/or discharging a pressurized fluid to or from the fluid channel (3) as needed.

Description

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

[0035] An embodiment of a system having an exemplary embodiment of the rotation transmission apparatus according to the invention is described in further detail below, with reference to the accompanying drawings. The figures show:

[0036] FIG. 1 shows in a schematically and in a lateral view, an exemplary embodiment of the rotation transmission apparatus according to the invention, being fastened on a shaft;

[0037] FIG. 2 show in a schematically and in an isometric longitudinal sectional view, the exemplary embodiment of the rotation transmission apparatus according to the invention according to FIG. 1;

[0038] FIG. 3 shows in a schematically and in a longitudinal sectional view, the exemplary embodiment of the rotation transmission apparatus according to the invention according to FIG. 1; and

[0039] FIG. 4 shows schematically, a detailed view of FIG. 3.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0040] Referring now to the illustrations in FIG. 1 to FIG. 4, an exemplary embodiment of the rotation transmission apparatus 1 according to the invention will first be described, being fastened on a shaft 2, in particular a drive shaft.

[0041] The shaft 2 is, for example, a drive shaft of a wheel drive for a steered and driven vehicle wheel. The drive shaft can have a first gear-side shaft, a universal joint, and a second axle-side shaft. Because such a drive shaft requires the steering axle of the wheel to be as close as possible to the wheel plane so that the steering rolling radius is kept as low as possible, there is a certain space problem with respect to the rotation transmission apparatus 1.

[0042] In particular, it is therefore necessary for such drive shafts for a steered and driven vehicle wheel to provide a particularly compactly designed rotation transmission apparatus 1, which is configured to be as wear-free as possible.

[0043] The rotation transmission apparatus 1, as shown together with the shaft 2 in the drawings, can in particular be part of a tire pressure control system of a motor vehicle.

[0044] The rotation transmission apparatus 1 is fastened on and, in particular, torsionally connected to, the drive shaft 2. Although not shown, the drive shaft 2 can be circumscribed by an axle housing on the vehicle side. The axle housing can, at least regionally, form the housing 13 of a stator assembly 4 of the rotation transmission apparatus 1.

[0045] Although not shown in the drawings, the free portion of the shaft 2, i.e., the wheel-side end region of the shaft 2, can be connected to the wheel unit, which is also not shown in the drawings, via the already mentioned universal joint, and thus functions figuratively to secure one or more wheels on the drive shaft 2 so that they can be driven by the drive shaft 2.

[0046] The rotation transmission apparatus 1 serves to transmit control and/or working pressures to a fluid channel 3 accommodated or formed at least regionally inside the shaft 2. For this purpose, the rotation transmission apparatus 1 comprises a stator assembly 4, which is arranged in a stationary manner relative to a rotational movement of the shaft 2 and has at least one fluid supply/discharge 5.

[0047] As can in particular be seen from the sectional views in FIG. 2 and FIG. 3, the fluid supply/discharge 5 opens into an annular space 6 at least partially or regionally coaxially surrounding the shaft 2.

[0048] The fluid channel 3 of the shaft 2 is also fluidically connected to this coaxially arranged annular space 6, preferably via a branch channel.

[0049] As will be described in more detail below with reference to the detailed view in FIG. 4, sealing elements 7 are associated with the annular space 6, which are arranged and configured at least partially or regionally in the annular space 6 such that they seal the annular space 6 from the outside atmosphere when an in particular previously defined or definable overpressure is applied in the annular space 6.

[0050] The stator assembly 4 of the rotation transmission apparatus 1 comprises a housing 13 which at least partially or regionally surrounds the shaft 2 and in which a rolling bearing assembly 14 is at least regionally accommodated. With the aid of the roller bearing assembly 14, the shaft 2 is rotatably supported relative to the stator assembly 4.

[0051] At least regionally or partially in the housing 13 of the stator assembly 4, a sealing sleeve 11 is provided. Specifically, the sealing sleeve 11 is pushed onto the shaft 2 and is preferably releasably connected to the shaft 2 in the region of the housing 13 of the stator assembly 4. Sealing elements 17 are used in order to seal the connection between the sealing sleeve 11 and the shaft 2. The sealing elements 17 are in particular at least one O-ring.

[0052] The sealing sleeve 11 has a sealing geometry 12 facing in the direction of the annular space 6, against which, at least regionally, the sealing elements 7 arranged in the annular space 6 sealingly abut when an overpressure is applied in the annular space 6.

[0053] For example, the sealing geometry 12 of the sealing sleeve 11 can comprise at least one region running radially around the shaft 2 and projecting or protruding towards the annular space 6, which forms the sealing seat for the sealing elements 7.

[0054] Radial shaft sealing rings are used as sealing elements 7 in the exemplary embodiment shown in the drawings. Each radial shaft sealing ring has an outer region 9 facing the stator assembly 4 and an inner region 10 facing the shaft 2, wherein the inner region 10 facing the shaft 2 serves as a sealing lip or sealing disc. Each radial shaft sealing ring is preferably exchangeable via its outer region 9, and in particular connected to the stator assembly 4 via a clamping connection.

[0055] For this purpose, the stator assembly 4 comprises a clamping ring or fastening assembly 15 for releasably or exchangeably fastening the radial shaft sealing rings (sealing elements 7) to the stator assembly 4 via their outer region 9. Corresponding sealing elements 16, in particular in the form of O-rings, are associated with the clamping ring or fastening assembly 15 for sealing the fastening region of the sealing elements 7.

[0056] The inner regions 10 of the radial shaft sealing rings (sealing elements 7) facing the shaft 2 and configured as sealing lips or sealing discs are configured such that they bear or can be brought to bear against the sealing sleeve 11 fastened to the shaft 2.

[0057] Specifically, the sealing lips or sealing discs 10 of the radial shaft sealing rings (sealing element 7) are implemented and/or arranged in the annular space 6 such that, when the annular space 6 is unpressurized, they have no contact to the sealing geometry 12 of the sealing sleeve 11 or only bears against the sealing geometry 12 of the sealing sleeve 11 of the shall 2 so lightly that, upon rotation of the shaft 2 relative to the stator assembly 4, the sealing sleeve 11 can slide over the sealing lips or sealing discs 10 without resistance or at least substantially without resistance.

[0058] On the other hand, the sealing lips or sealing discs 10 of the radial shaft sealing rings (sealing element 7) are implemented and/or arranged in the annular space 6 such that, when overpressure is applied in the annular space 6, it bears against the sealing geometry 12 of the sealing sleeve 11 of the shaft 2 in a sealing manner.

[0059] Here, it is expedient that the sealing lips or sealing discs 10 are further configured such that they return to their at least substantially contact-free state when a previously set overpressure in the annular space 6 is released again.

[0060] Briefly summarized, the exemplary embodiment of the rotation transmission apparatus 1 according to the invention shown in the drawings can be characterized as follows:

[0061] In order to reduce wear and frictional losses to a minimum during operation of the rotation transmission apparatus 1, the rotation transmission apparatus 1 is configured such that the corresponding seal elements 7 in the annular space 6 engage with or come into contact with the sealing geometry 12 of the sealing sleeve 11 of the rotating drive shaft 2 relative to the stator assembly 4 only for the period of time of transfer of the pressurized medium to the fluid channel 3 formed in the shaft 2.

[0062] The drive shaft 2, which is embodied for example as a hollow or partially hollow shaft, can have any number of channel guides (fluid channels 3). Any fluid channel 3 of drive shaft 2 running parallel to the axis of rotation of drive shaft 2 can have any number of branch channels to the drive shall surface, wherein all branch channels located in the region of the stator assembly 4 “see” the same control pressure.

[0063] The outer contour (topology) of the drive shaft 2 is preferably created such that the drive shaft 2 has sealing portions in the region of transmission relative to the axis of rotation.

[0064] The described exemplary embodiment relates to a single-channel rotary feedthrough, but two-channel rotary feedthroughs with a working channel and a control channel are also conceivable. Similarly, the rotation transmission apparatus 1 can also be realized with more than two channels.

[0065] The description of the invention makes it clear that the rotation transmission apparatus 1 according to the invention is above all also suitable for retrofitting.

[0066] The invention is not limited to the embodiments shown in the drawings, but rather results when all of the features disclosed herein are considered together.