Wheel hub for a commercial vehicle drive axle

Abstract

The invention relates to a wheel hub (6) for a commercial vehicle drive axle, comprising a hollow section (11) which transitions at a first axial end (12) into a flange section (13) that projects radially outwards relative to the hollow section (11) and is provided for mounting at least one wheel rim (7, 8). The hollow section (11) is provided in the region of the first axial end (12) with centering sections (19) that define a centering outer diameter (21) of the hollow section (11) for centering the at least one wheel rim (7, 8) on the hollow section (11) and are separated from each other circumferentially by intermediate sections (20), each of which is radially recessed relative to the centering sections (19). To reduce the manufacturing effort of the wheel hub (6), the intermediate sections (20) are formed by machining the hollow section (11) between the centering sections (19).

Description

[0001] The invention relates to a wheel hub for a commercial vehicle drive axle, comprising a hollow section which, at a first axial end, merges into a flange section which projects radially outward relative to the hollow section and is provided for fastening at least one wheel rim. The hollow section is provided with centering sections in the region of the first axial end which define a centering outer diameter of the hollow section for centering the at least one wheel rim on the hollow section and are separated from one another in the circumferential direction by intermediate sections which are each radially set back with respect to the centering sections. The invention further relates to a commercial vehicle drive axle with the aforementioned wheel hubs.

[0002] In motor vehicle drive axles, it is common practice to couple drive shafts within each drive axle to associated wheel hubs, each of which serves to attach at least one associated vehicle wheel. In commercial vehicle drive trains, wheel hubs are sometimes also designed as bell-shaped hubs, to which two vehicle wheels can often be attached as twin tires. For this purpose, a bell-shaped hub usually has a hollow section and a flange section, with the vehicle wheel(s) then placed on the hollow section and attached to the flange section. A bell-shaped hub is usually also used to accommodate a wheel hub gear, which can be used to implement an additional transmission ratio in the power flow between the individual drive shaft and the vehicle wheel(s) attached to the bell-shaped hub, and which is often designed as a planetary gear.

[0003] DE 10 2008 014 105 A1 discloses a wheel hub which is designed as a cast part and consists of a hollow section and a flange section. A transition from the hollow section to the flange section is made at one axial end of the hollow section, wherein the flange section protrudes radially outward relative to the hollow section and serves to fasten at least one wheel rim of each vehicle wheel. At the axial end, and thus directly in the region of the transition from the hollow section to the flange section, the hollow section is also equipped with centering sections which define a centering outer diameter of the hollow section. Intermediate sections are formed in the circumferential direction between the centering sections, which separate the centering sections from one another in the circumferential direction and are each radially set back relative to the centering sections.

[0004] Based on the prior art described above, the object of the present invention is to create a wheel hub which is characterized by low manufacturing costs.

[0005] This object is achieved based on the preamble of claim 1 in conjunction with its characterizing features. The dependent claims that follow therefrom each represent advantageous developments of the invention. A drive axle having wheel hubs according to the invention is further the subject of claim 7.

[0006] According to the invention, a wheel hub comprises a hollow section, which at a first axial end transitions into a flange section, which protrudes radially outward relative to the hollow section and is provided for fastening at least one wheel rim. The hollow section is provided at the first axial end with centering sections, which define a centering outer diameter of the hollow section for centering the at least one wheel rim on the hollow section and are separated from one another in the circumferential direction by intermediate sections, each of which is radially recessed relative to the centering sections.

[0007] The wheel hub according to the invention thus has a hollow section and a flange section, which are axially adjacent to one another in that the hollow section merges into the flange section at a first axial end. The flange section projects radially outwards relative to the hollow section and serves to fasten at least one wheel rim to the wheel hub. For this fastening, the flange section, like the hollow section, is designed in particular to be circumferential, wherein the flange section is also preferably provided with fastening points in the form of through-bores, which are designed in particular to be equidistant from one another in the circumferential direction and each serve to pass through a wheel bolt for fastening the at least one wheel rim. The flange section of the wheel hub is thus preferably designed to be screwed to the at least one wheel rim in order to fasten the wheel rim to the wheel hub.

[0008] In the context of the invention, “axial” is to be understood as a parallel course to a rotational axis of the wheel hub, while “radial” in the sense of the invention means a course in the diameter direction with a center point lying on the rotational axis.

[0009] The hollow section of the wheel hub is a hollow body-shaped section of the wheel hub, wherein the hollow section is preferably designed in the shape of a hollow cylinder or hollow cylinder-like.

[0010] In the region of the first axial end, at which the hollow section transitions into the flange section, a centering outer diameter of the hollow section is also defined, wherein this centering outer diameter is intended to center the at least one wheel rim to be attached to the wheel hub on the hollow section and thus also in relation to the flange section. The centering outer diameter is defined via centering sections that are configured at the axial end of the hollow section and separated from one another by intermediate sections located therebetween in the circumferential direction. In this respect, in the region of the first axial end, centering sections and intermediate sections alternate in the circumferential direction of the hollow section.

[0011] The intermediate sections are radially recessed from the centering sections, i.e., they are positioned on an outer diameter of the hollow section that is smaller than the centering outer diameter. This reduces the contact surface at which contact occurs between a wheel rim attached to the flange section and the hollow section, as this contact surface is interrupted circumferentially by the intermediate sections. This also results in a corresponding reduction in the area for corrosion of the wheel rim at the hollow section of the wheel hub, making it easier to remove the wheel rim from the wheel hub.

[0012] In the sense of the invention, the wheel hub is preferably designed in one piece, so that the hollow section and the flange section are sections of one and the same component.

[0013] The invention now encompasses the technical teaching that the intermediate sections are formed by machining the hollow section between the centering sections. In other words, the intermediate sections located circumferentially between the centering sections and radially recessed relative to the centering sections are produced by machining the corresponding areas between the centering sections.

[0014] Such a wheel hub design has the advantage that the radially recessed intermediate sections can be formed with low manufacturing effort, while simultaneously achieving a high degree of precision. This allows for a simple and reliable reduction in the contact area between the wheel rim attached to the flange section and the hollow section. Furthermore, this can easily be performed retrospectively, i.e., on a wheel hub that has already been manufactured and may even have already been in use.

[0015] For the purposes of the invention, "machining" refers to machining of the wheel hub according to the invention in which the intermediate sections of the hollow section are produced by machining, i.e., the intermediate sections are mechanically defined by removing excess material in the form of chips. In this respect, the intermediate sections, which are radially recessed relative to the centering sections, were only manufactured during machining of the wheel hub and were therefore not produced by forming or primary forming.

[0016] According to one embodiment of the invention, the hollow section transitions into a base section at a second axial end opposite the first axial end. The base section extends radially inward from the hollow section and, together with the hollow section, defines an interior space. This gives the wheel hub a pot-like shape, so that it is designed in the manner of a bell-shaped hub.

[0017] In a further development of the aforementioned embodiment, axially projecting webs are formed on the base section on the interior side, each of which is provided for guiding a planetary gear of a planetary gear set. As a result, the wheel hub according to the invention forms at least part of a planet carrier of the planetary gear set, the components of which are preferably accommodated in the interior space delimited by the base section and the hollow section. When the wheel hub according to the invention is used in a commercial vehicle drive axle, a compact design of the commercial vehicle drive axle can be advantageously achieved by integrating a planetary gear set into the wheel hub as a wheel hub transmission, thereby providing an additional transmission ratio for guiding the power flow between a respective drive shaft and the vehicle wheel(s) attached to the wheel hub.Due to the separation of the centering sections of the wheel hub by the intermediate sections in between, it can also be easier to detach a respective wheel rim of the attached vehicle wheel(s) from the wheel hub in the event of corrosion.

[0018] According to one possible embodiment of the invention, an outer diameter of the hollow section is reduced, starting from the centering outer diameter, towards a second axial end opposite the first axial end. This simplifies the sliding of a wheel rim, which is to be fastened to the flange section, onto the wheel hub. When combined with the preceding variant, the reduction of the outer diameter of the hollow section preferably takes place to a diameter at the second axial end that is only slightly smaller than the centering outer diameter. This ensures that the interior is sufficiently dimensioned to accommodate the planetary gear set. The reduction of the outer diameter is implemented in particular linearly, whereby the hollow section has a conical or slightly conical shape. However, the hollow section is particularly preferably designed to be essentially hollow-cylindrical.

[0019] In a further development of the invention, the centering sections and the intermediate sections are configured axially on the hollow section in a region in which the at least one wheel rim is to be placed on the hollow section for attachment to the flange section. This region, in which the centering sections and the intermediate sections are configured alternatingly in the circumferential direction, can be axially directly adjacent to the flange section or can be spaced from the flange section via an axially intermediate region of the hollow section.It is essential that the centering sections and the intermediate sections are formed in the region of the hollow section in which the placement of the at least one wheel rim on the hollow section takes place during attachment to the flange section, i.e. in which the centering of the at least one wheel rim on the hollow section and thus also the contact with the hollow section is carried out.

[0020] One embodiment of the invention is for the wheel hub to be designed as a cast part. This allows for the wheel hub to be manufactured with low manufacturing costs. In particular, after the primary forming of the wheel hub, at least parts of the wheel hub are subjected to machining, preferably an outer side of the hollow section. In any case, after the primary forming of the wheel hub, the hollow section is machined to form the intermediate sections located between the centering sections.

[0021] The invention also relates to a commercial vehicle drive axle having drive shafts, wherein the drive shafts are each coupled to a respective wheel hub according to one or more of the variants described above. The coupling of the respective drive shaft to the respective wheel hub is achieved in particular via a planetary gear set, which functions as a wheel hub transmission or as part of a wheel hub transmission.

[0022] An advantageous embodiment of the invention, which is explained below, is illustrated in the drawings. It shows: Fig. 1 is a sectional view of part of a commercial vehicle drive axle; Fig. 2 a perspective view of a wheel hub of the commercial vehicle drive axle from Fig. 1, according to a preferred embodiment of the invention; and Fig. 3 a sectional view of the wheel hub from Fig. 2.

[0023] Out of Fig. 1 shows a sectional view of part of a commercial vehicle drive axle 1, wherein the commercial vehicle drive axle 1 is shown in the area of ​​a twin tire assembly 2. Drive wheels 3 and 4 of the twin tire assembly 2 can be driven in the commercial vehicle drive axle 1 via an associated drive shaft (not shown here), for which purpose the drive shaft is coupled via an intermediate wheel hub gear 5 to a wheel hub 6, to which the drive wheels 3 and 4 of the twin tire assembly 2 are each attached with associated wheel rims 7 and 8. The wheel hub gear 5 is designed as a planetary gear set, which in Fig. 1, however, is only indicated very schematically. The drive wheels 3 and 4 are attached to the wheel hub 6 by their wheel rims 7 and 8 via screw connections 9, with the wheel rims 7 and 8 being centered on the wheel hub 6 in an area 10.

[0024] The wheel hub 6 is realized according to a preferred embodiment of the invention and is also in the Fig. 2 and Fig. 3. As can be seen here, the wheel hub 6 comprises a hollow section 11, which at a first axial end 12 merges into a circumferential flange section 13 and at a second axial end 14 into a base section 15. The hollow section 11 essentially has a hollow cylindrical shape, against which the flange section 13 protrudes radially outwards. In the flange section 13, a plurality of equidistantly spaced through holes 16 are introduced, through which wheel bolts for implementing the screw connections 9 from Fig. 1 can be passed through.

[0025] On the other hand, the base section 15 extends radially inwards from the hollow section 11 and, together with the hollow section 11, defines an interior space 17 in which, in the installed state of the wheel hub 6, the wheel hub gear 5 is arranged. Fig. 1. Furthermore, the base portion 15 has webs 18 projecting axially into the interior 17, each of which is provided for guiding a respective planetary gear of the wheel hub transmission 5. In this respect, the wheel hub 6 forms at least part of a planetary carrier of the wheel hub transmission 5.

[0026] The area 10, in which the wheel rims 7 and 8 are centered on the wheel hub 6, is provided in the hollow section 11 in the area of ​​the axial end 12 and thus adjacent to the flange section 13. In this area 10, the hollow section 11 is provided with centering sections 19 and intermediate sections 20, which are arranged alternately in the circumferential direction in the area 10. In this respect, two centering sections 19 are separated from each other by an intermediate section 20 each.

[0027] The centering sections 19 define a centering outer diameter 21 of the hollow section 11, wherein this centering outer diameter 21 is Fig.3 is indicated. The intermediate sections 20 are radially recessed from the centering sections 19 and thus have a diameter 22 that is smaller than the centering outer diameter 21. This reduces the respective contact surface of the wheel hub 6 on the hollow section 11 with the wheel rims 7 and 8 centered thereon, whereby in the event of corrosion, the reduced contact surface makes it easier to detach the wheel rims 7 and 8 from the wheel hub 6. Furthermore, starting from the area 10 and thus from the centering outer diameter 21, a reduction in the outer diameter of the hollow section 11 towards the axial end 14 takes place.

[0028] The wheel hub 6 is designed as a cast part, so that the hollow section 11, the flange section 13, and the base section 15 were manufactured using a primary forming process. As a special feature, the intermediate sections 20 between the centering sections 19 were formed by machining the hollow section 11 following the primary forming process, by removing material from the corresponding circumferential sections of the hollow section 11. This allows the corresponding design of the area 10 with the centering sections 19 and the intermediate sections 20 of the wheel hub 6 to be achieved with low manufacturing costs.

[0029] By means of the design according to the invention, a wheel hub can be realized with low manufacturing costs. Reference symbol 1 commercial vehicle drive axle 2 twin tires 3 drive wheel 4 drive wheel 5 wheel hub gears 6 Wheel hub 7 Wheel rim 8 wheel rim 9 screw connections 10 Area 11 Hollow section 12 axial end 13 Flange section 14 axial end 15 floor section 16 through holes 17 Interior 18 bridges 19 centering sections 20 intermediate sections 21 centering outer diameter 22 diameters QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2008 014 105 A1

[0003]

Claims

[1] Wheel hub (6) for a commercial vehicle drive axle (1), comprising a hollow section (11) which, at a first axial end (12), merges into a flange section (13) which projects radially outwards relative to the hollow section (11) and is provided for fastening at least one wheel rim (7, 8), wherein the hollow section (11) is provided in the region of the first axial end (12) with centering sections (19) which define a centering outer diameter (21) of the hollow section (11) for centering the at least one wheel rim (7, 8) on the hollow section (11) and are separated from one another in the circumferential direction by intermediate sections (20) which are each radially set back with respect to the centering sections (19), characterized by that the intermediate sections (20) have been formed by machining the hollow section (11) between the centering sections (19). [2] Wheel hub (6) according to claim 1, characterized bythat the hollow section (11) merges at a second axial end (14) opposite the first axial end (12) into a base section (15) which, starting from the hollow section (11), extends radially inwards and, together with the hollow section (11), delimits an interior space (17). [3] Wheel hub (6) according to claim 2, characterized by that axially projecting webs (18) are formed on the bottom section (15) on the side of the interior space (17), each of which is provided for a guide of a planetary gear of a planetary gear set. [4] Wheel hub (6) according to one of claims 1 to 3, characterized by that an outer diameter of the hollow section (11) reduces from the centering outer diameter (21) to a second axial end (14) opposite the first axial end (12). [5] Wheel hub (6) according to one of the preceding claims, characterized bythat the centering sections (19) and the intermediate sections (20) on the hollow section (11) are configured axially in a region (10) in which the at least one wheel rim (7, 8) is to be placed on the hollow section (11) for fastening to the flange section (13). [6] Wheel hub (6) according to one of the preceding claims, characterized by a version as a cast part. [7] Commercial vehicle drive axle (1), comprising drive shafts, each coupled to an associated wheel hub (6) according to one or more of claims 1 to 6.

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