Gear unit with a housing part with a driving shaft
The gearbox design with an annular gap and integrated cooling pipes addresses thermal power losses by enhancing turbulence and positioning cooling medium flow close to the heat source, achieving efficient heat dissipation with minimal space requirements.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SEW EURODRIVE GMBH & CO KG
- Filing Date
- 2025-11-17
- Publication Date
- 2026-07-02
AI Technical Summary
Existing gearboxes suffer from thermal power losses during operation, and existing cooling solutions do not effectively address these losses while maintaining a compact design.
A gearbox design featuring a housing part with an annular gap between a ring-shaped bearing receptacle and a cover plate, incorporating projections to enhance turbulence and a cooling medium flow, with integrated cooling pipes positioned close to the heat source, allowing efficient heat dissipation.
The design achieves efficient heat dissipation with minimal installation space, reducing thermal resistance and maintaining a compact gearbox form factor.
Smart Images
Figure EP2025083303_02072026_PF_FP_ABST
Abstract
Description
[0001] Gearbox with a housing part with an incoming shaft
[0002] Description:
[0003] The invention relates to a gearbox with a housing part with an input shaft.
[0004] It is known that gearboxes exhibit thermal power losses during operation.
[0005] From CN 1 10805689 A, a gearbox is known as the closest prior art.
[0006] A liquid-cooled housing part is known from CN 1 13669436 A.
[0007] A planetary gear is known from CN 1 19906 194 A.
[0008] A cooling device for planetary gear transmissions is known from DE 1298819 A.
[0009] A branch gearbox with a cooling jacket is known from DE 3331 038 A1.
[0010] The invention is therefore based on the objective of further developing a compact gearbox.
[0011] According to the invention, the problem is solved in the transmission according to the features specified in claim 1.
[0012] Important features of the invention are that the gearbox is provided with a housing part and with a driving shaft, wherein an annular gap through which a cooling medium flows is formed between the housing part, in particular between a ring-shaped, in particular hollow cylindrical bearing receptacle formed on the housing part, and a cover plate of the gearbox, which radially surrounds one or the hollow cylindrical bearing receptacle formed on the housing part.
[0013] in particular wherein a bearing of the driving shaft is received in the bearing housing
[0014] in particular wherein the bearing receptacle is a hollow cylindrically shaped area of the housing part.
[0015] ISI \ EIDOPAT 17.11.2025 An advantage of this is that efficient heat dissipation of the housing part can be achieved. In particular, the cover part can be provided in the axial area that is covered by the bearing in the axial direction.
[0016] In an advantageous embodiment, projections are formed on the housing part, particularly on the bearing receptacle, which are spaced apart from one another in the circumferential direction, in particular uniformly spaced from one another, and project radially outwards from the bearing receptacle towards the cover plate, in particular projecting through the annular gap. It is advantageous that the projections make the cooling medium flow more turbulent and thus enable a lower thermal resistance.
[0017] In an advantageous embodiment, the cover plate rests on the raised sections. It is advantageous that the annular gap is located between the bearing receptacle of the housing part and the cover plate.
[0018] In an advantageous embodiment, the cover plate is bonded to the raised sections by a material bond, in particular by welding. The advantage here is that a secure and durable connection can be used.
[0019] In an advantageous embodiment, the longest extension of each elevation is formed and / or aligned in a direction transverse to the flow direction and / or in an axial direction, in particular parallel to the direction of rotation.
[0020] In particular, the flow direction, especially the main flow direction, of the cooling medium is essentially oriented circumferentially. It is advantageous that the protrusions are perpendicular to the flow direction and thus cause effective turbulence of the cooling medium flow.
[0021] In an advantageous embodiment, the axial width of the respective projection is smaller than the axial width of the annular gap. This is advantageous because the cooling medium flow still has sufficient clearance to flow circumferentially. In an advantageous embodiment, the annular gap is bounded and / or covered radially outwards by a cover plate.
[0022] In particular, the cover plate consists of flat areas with bending edges between them. An advantage of this design is that heat is radiated to the surroundings even through the thin cover plate, and the additional installation space required for the cooling system is extremely minimal. Specifically, only a radial allowance is necessary, equal to the radial width of the protrusions and the cover plate. However, the cover plate follows the protrusions, which all have the same radial width, and is therefore curved or made of flat individual surface pieces arranged at angles to each other.
[0023] In an advantageous embodiment, the annular gap, in the circumferential angle region not covered by the cover plate, is arranged in an annular groove section integrated into the housing part, which radially surrounds the bearing receptacle in this circumferential angle region. It is advantageous that the annular gap is limited radially outwards either by a cover plate or by the housing part itself. A two-piece design of the cover plate is also included.
[0024] In an advantageous embodiment, a flange area is formed on the drive side of the housing part, in which annular grooves arranged concentrically to each other and concentrically to the axis of rotation of the driving shaft are machined.
[0025] wherein semicircular ring tubes are accommodated in the ring grooves.
[0026] An advantage of this design is the compact design of the gearbox, as the cooling pipe system is integrated within the gearbox and requires little installation space. In particular, the cooling pipe system is integrated into the input-side flange area. Since the rapidly rotating input shaft generates a high temperature and therefore a high heat flow, efficient heat dissipation can be achieved according to the invention. This is because the cooling pipe system is positioned as close as possible to the bearing arrangement for the input shaft, which acts as a heat source.
[0027] In an advantageous embodiment, connecting parts and a connection part are arranged on the flange area of the housing part, in particular wherein the connecting parts and the connection part are each pressed against the flange area by means of screws screwed into threaded bores of the flange area,
[0028] In particular, the screws protrude through the connecting parts and the terminal part. It is advantageous that fastening to the input-side end face is possible.
[0029] In an advantageous embodiment, each of the connecting parts connects a semicircular annular tube to a neighboring annular tube arranged radially inside it in a first circumferential half. It is advantageous that the cooling medium flow first meanders through the semicircular annular tubes from radially outside to radially inside in the first circumferential half, and then meanders through the semicircular annular tubes from radially inside to radially outside in the remaining circumferential half.
[0030] In an advantageous embodiment, each of the connecting parts connects a semicircular annular tube in the other circumferential half to a neighboring annular tube arranged radially inside that annular tube. It is advantageous that the cooling medium flow first meanders through the semicircular annular tubes from radially outside to radially inside in the first circumferential half, and then meanders through the semicircular annular tubes from radially inside to radially outside in the remaining circumferential half.
[0031] In an advantageous embodiment, the connecting part connects a first channel formed in the housing part to a first opening of a first, radially outermost, semi-annular ring tube. The advantage here is that a simple and cost-effective connection can be achieved.
[0032] In an advantageous embodiment, the connecting part links a second channel formed in the housing part to a first opening of a second, radially outermost, semi-annular ring tube. The advantage here is that a simple and cost-effective connection can be achieved.
[0033] In an advantageous embodiment, the radially innermost ring tube is designed as a solid ring tube and is connected to the radially innermost connecting part. The advantage here is that a simple, cost-effective connection can be achieved. In an advantageous embodiment, spacers are arranged radially between the ring tubes.
[0034] In particular, those that are pressed against the flange area by screws screwed into threaded holes in the flange area. An advantage of this method is that the spacing is easily ensured.
[0035] In a preferred design, the first channel leads to an inlet connection and the second channel to an outlet connection. The advantage here is that the inlet and outlet of the cooling medium are very compact, thus saving installation space. In particular, the cooling medium also flows directly through the housing component and thus absorbs heat directly from it.
[0036] In an advantageous embodiment, the first channel extends in the axial direction, in particular parallel to the axis of rotation of the driving shaft, and through the housing part, specifically projecting through the flange area that extends radially from the housing part. An advantage of this is that heat is transferred directly from the housing part into the cooling medium.
[0037] In an advantageous embodiment, the second channel extends axially, in particular parallel to the axis of rotation of the driving shaft, and projects through the housing part, especially through the flange area projecting radially from the housing part. An advantage of this is that heat is transferred directly from the housing part into the cooling medium.
[0038] In an advantageous embodiment, the flange area has a continuous bearing bore through which the driving shaft protrudes,
[0039] where a bearing of the driving shaft is accommodated in the bearing bore. An advantage of this design is that the inner ring of the bearing is mounted on the driving shaft, while the outer ring of the bearing is accommodated in the bearing bore. This allows the heat loss from the bearing to flow directly into the flange area.
[0040] In an advantageous embodiment, each annular tube is designed as a lamellar annular tube, in particular wherein continuous lamellae project radially from the tube in the circumferential direction and / or wherein the lamellae are uniformly spaced apart from one another. It is advantageous that the lowest possible thermal resistance between the lamellar annular tube and the housing part can be achieved. Furthermore, preferably, the respective annular tube is encased in a thermally conductive potting compound and provided in the respective annular groove.
[0041] Further advantages arise from the dependent claims. The invention is not limited to the combination of features of the claims. For those skilled in the art, further meaningful combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent, in particular from the problem statement and / or the problem arising from a comparison with the prior art. The invention will now be explained in more detail with reference to schematic illustrations:
[0042] Figure 1 shows a gearbox with an additional, in particular optional, cooling arrangement in oblique view.
[0043] Figure 2 shows this gearbox open on the input side.
[0044] Figure 3 shows an exploded oblique view of the additional, in particular optional, cooling pipe arrangement located on the input side of the gearbox.
[0045] Figure 4 shows an exploded view of a cooling arrangement of the gearbox according to the invention.
[0046] Figure 5 shows the cooling arrangement of the gearbox according to the invention in an oblique view.
[0047] As shown in the figures, the gearbox has a housing part 1 which provides a flange area 7 on the input side of the gearbox and which accommodates a bearing of the input shaft of the gearbox.
[0048] On its side facing away from the flange area 7, the housing part 1 is connected to a bearing flange 4, which accommodates a bearing of the driving shaft, in particular a hollow shaft.
[0049] Preferably, the gearbox is designed as a coaxial gearbox, in particular a planetary gearbox.
[0050] As shown in Figure 2, the flange area 7 has concentrically arranged annular grooves 22.
[0051] A connecting part 20 and connecting parts 21 are arranged radially one behind the other. The connecting part 20 is arranged radially outside the connecting parts 21. Semi-ring-shaped ring tubes 30 are received in the annular grooves 22, and their circumferential end regions are each connected to a respective connecting part 21.
[0052] Each connecting part 21 connects a first of the semicircular ring tubes 30 with a second semicircular ring tube 30 arranged radially inside the first, which is arranged in the same circumferential angle range as the first.
[0053] In the remaining circumferential angle range i arranged outside this circumferential angle range, each connecting part 21 also connects a third of the semicircular ring tubes 30 with a fourth, radially inside the third semicircular ring tube 30, which is arranged in the same circumferential angle range as the third.
[0054] A supply connection 2 enables the supply of a cooling medium through a channel formed in the housing part 1 to the connection part 20.
[0055] The connecting part 20 is connected to the two radially outermost ring tubes 30, which are connected diametrically opposite the connecting part 20 to a first connecting part.
[0056] In this way, the cooling medium, in particular water or oil, flows through the radially outermost annular tube 30 in the first circumferential angle range and then successively through the further radially inner annular tubes with alternating flow directions, in particular circumferential or counter-circular, until the radially innermost annular tube 30, which is designed as a solid ring and thus returns the cooling medium from radially inner to radially outer through the semicircular annular tubes in the other circumferential angle range to the outermost semicircular annular tube 30, from where it is diverted by the connection part 20 through a channel formed in the housing part 1 to the outlet connection 3.
[0057] In summary, the cooling medium flows through the semi-annular ring tubes 30 in the first circumferential half, successively from the radial outside to the radial inside, until it reaches the essentially full-ring, radially innermost ring tube 30. From there, it flows through the other circumferential half, successively from the radial inside to the radial outside. This method of heat dissipation from the flange area 7 achieves efficient heat dissipation from the driving side. It is important to note that the bearing of the driving shaft and a shaft seal located next to this bearing act as two significant sources of heat loss.
[0058] The axial direction is aligned parallel to the axis of rotation of the driving shaft, and the radial direction is relative to this axis of rotation of the driving shaft. Similarly, the circumferential direction is relative to the axis of rotation of the rotor shaft.
[0059] As shown in Figure 4 and Figure 5, a cooling arrangement according to the invention is implemented on the housing part.
[0060] The cooling medium flows through an annular gap, on the radial inside of which radially directed protrusions 40 are arranged, which generate turbulence in the cooling medium and thus a more efficient heat transfer from the housing part to the cooling medium.
[0061] The elevations 40 are spaced apart from each other in the circumferential direction and are formed on a hollow cylindrical bearing receptacle, from which they each project in a radially outward direction.
[0062] A cover plate 41 defines the radial outer boundary of the annular gap. The cover plate 41 has circumferentially arranged regions, each with a bending edge between them. These regions are preferably planar or preferably have at least one planar section. The regions 41 and 41 have a non-zero angle with their nearest adjacent region and are therefore not parallel.
[0063] The cover plate 41 rests on the projections 40 and thus defines and limits the space for the cooling medium. Preferably, the cover plate 41 is welded to the projections 40.
[0064] A supply connection 2 is arranged on the housing part, which is connected to the space for the cooling medium via a channel formed in the housing part 7.
[0065] An outlet connection 3 is arranged on the housing part, which is connected to the space for the cooling medium 3 via a channel formed in the housing part 7. Thus, the heat dissipation of the gearbox via the two cooling arrangements is possible – either simultaneously or alternatively.
[0066] In the area not covered in the circumferential direction by the cover plate 41, the annular gap is realized as an annular groove of the housing part, with the radial outside of the hollow cylindrical bearing receptacle acting as the radial inside of the annular gap.
[0067] In further embodiments according to the invention, a plastic injection molded part is used instead of the cover plate 22 and is glued to the protrusions 40 instead of
[0068] welded. Reference list
[0069] 1 housing part
[0070] 2 Supply connection
[0071] 3. Outlet connection
[0072] 4 bearing flange
[0073] 5 Supply line connection
[0074] 6. Outlet connection
[0075] 7 Flange area
[0076] 20 Connection part
[0077] 21 Connecting part
[0078] 22 Ring groove
[0079] 30 ring tube
[0080] 31 spacers
[0081] 40 Survey
[0082] 41 Cover plate
Claims
Patent claims:
1. Gearbox with a housing part and with an input shaft, characterized by the fact that an annular gap through which a cooling medium flows is formed between the housing part, in particular between a ring-shaped, especially hollow cylindrical bearing receptacle formed on the housing part, and a cover plate of the gearbox, which radially surrounds one or the hollow cylindrical bearing receptacle formed on the housing part, in particular wherein a bearing of the driving shaft is received in the bearing housing 2. Gearbox according to claim 1, in particular wherein the bearing receptacle is a hollow cylindrically shaped area of the housing part. characterized by the fact that on the housing part, in particular on the bearing receptacle, projections are formed which are spaced apart from each other in the circumferential direction, in particular are spaced evenly apart from each other, and project radially outwards from the bearing receptacle towards the cover plate, in particular projecting through the annular gap, and / or that the cover plate rests on the raised areas and / or that the cover plate is bonded to the raised areas by a material connection, in particular by welding.
3. Transmission according to any of the preceding claims, characterized by the fact that the longest extent of the respective elevation is formed in a direction transverse to the flow direction and / or in an axial direction, in particular parallel to the direction of rotation, in particular wherein the flow direction, especially the main flow direction, of the cooling medium is essentially oriented in the circumferential direction.
4. Transmission according to any of the preceding claims, characterized by the fact that the axial width of the respective elevation is smaller than the axial width of the annular gap.
5. Transmission according to any of the preceding claims, characterized by the fact that the annular gap is bounded and / or covered radially outwards by a cover plate. - 14 - 6. Transmission according to any of the preceding claims, characterized by the fact that The cover plate consists of flat areas with bending edges arranged between them.
7. Gearbox according to any of the preceding claims, characterized by the fact that The annular gap in the circumferential angle range which is not covered by the cover plate is arranged in an annular groove section incorporated into the housing part, which radially surrounds the bearing receptacle in the circumferential angle range.
8. Gearbox according to any of the preceding claims, characterized by the fact that a flange area is formed on the drive side of the housing part, in which annular grooves arranged concentrically to each other and concentrically to the axis of rotation of the driving shaft are machined, wherein semicircular ring tubes are accommodated in the ring grooves, in particular wherein connecting parts and a connection part are arranged on the flange area of the housing part, in particular wherein the connecting parts and the connecting part are each pressed against the flange area by means of screws screwed into threaded holes in the flange area, especially where the screws protrude through the connecting parts and the connecting part.- 15- 9. Gearbox according to any of the preceding claims, characterized by the fact that Each of the connecting parts connects a semicircular ring tube in a first circumferential half with a next adjacent ring tube arranged radially inside this ring tube. and / or that Each of the connecting parts connects a semicircular ring tube in the other circumferential half to a neighboring ring tube arranged radially inside this ring tube. and / or that the connecting part connects a first channel formed in the housing part with a first opening of a first, radially outermost, semi-ring-shaped annular tube.
10. Gearbox according to any of the preceding claims, characterized by the fact that The connecting part connects a second channel formed in the housing part with a first opening of a second, radially outermost, semi-ring-shaped annular tube.
11. Gearbox according to any of the preceding claims, characterized by the fact that The radially innermost ring tube is designed as a solid ring tube and is connected to the radially innermost connecting part.
12. Gearbox according to any of the preceding claims, characterized by the fact that Spacers are arranged radially between the ring tubes. in particular those which are pressed against the flange area by screws screwed into threaded holes in the flange area.- 16- 13. Gearbox according to any of the preceding claims, characterized by the fact that the first channel leads into an inlet connection (5) and the second channel into an outlet connection (6).
14. Gearbox according to any of the preceding claims, characterized by the fact that the first channel extends in the axial direction, in particular parallel to the axis of rotation of the driving shaft, and projects through the housing part, in particular through the flange area projecting radially from the housing part, and / or that the second channel extends in the axial direction, in particular parallel to the axis of rotation of the driving shaft, and projects through the housing part, in particular through the flange area projecting radially from the housing part. and / or that the flange area has a continuous bearing bore through which the driving shaft protrudes, wherein a bearing of the driving shaft is received in the bearing bore.
15. Gearbox according to any of the preceding claims, characterized by the fact that Each ring tube is designed as a lamellar ring tube, in particular wherein continuous lamellae project radially from the tube in the circumferential direction and / or wherein the lamellae are evenly spaced apart from each other on the tube.