GEARBOX HOUSING WITH DRILLED OIL HOLLOW

Description

[0001] The invention relates to a gearbox housing with at least several side walls, wherein at least one of the side walls has one or more housing openings for receiving a bearing, and wherein a ribbed structure is formed on the inner side of a side wall, tapering vertically above a housing opening in a funnel shape towards the housing opening. Spray oil or lubricating oil is collected via the ribbed structure in order to supply it, for example, to a bearing of gearbox components housed in the gearbox housing.

[0002] The collection and fluid flow of splashed or lubricating oil within a gearbox housing is typically achieved via relatively complex cast-in oil guide ribs and / or oil collection pockets. These oil guide ribs primarily serve the described oil flow purpose and not any stiffening or reinforcement of the housing structure itself. There is a constant need to improve gearbox housings with regard to the collection and fluid flow of splashed or lubricating oil, while also considering the aspect of stiffening and reinforcing the housing structure. CN 104048022 B shows a gearbox housing with a U-shaped rib structure on the lower flank, where an undercut is cast to create a collection basin. To allow the oil collecting there to flow to the bearing, a bore is drilled vertically upwards from the bearing seat, enabling communication between the bore and the collection basin.US Patent 3,785,458 shows a bearing lubrication system using a bearing cap and an oil bore. DE 10 2021 002928 A1 shows a gearbox housing with a horizontal bore in one side wall. An oil collection basin is provided on the inside of the housing. The collection basin extends deeper than the bore in the vertical direction. EP 3,499 091 A1 shows a gearbox housing in which a gear is rotatably mounted via a bearing. The bearing is supplied with lubricating oil via an oil channel. CN 112 065 875 A shows a gearbox housing with an internal, funnel-shaped ribbed structure. The ribbed structure terminates in a through-hole at the highest point of a bearing mounting opening. Oil collected by the ribbed structure can pass through this through-hole to the bearing mounting opening.

[0003] The object of the invention is to demonstrate measures that enable an improvement in the collection and guidance of splashing oil or lubricating oil with regard to the stiffening and reinforcement of the housing structure.

[0004] The problem is solved by a gearbox housing having the features of claim 1. Preferred embodiments are specified in the dependent claims and the following description, each of which, individually or in combination, can represent an aspect of the invention. When a feature is presented in combination with another feature, this serves only to simplify the presentation of the invention and is in no way intended to imply that this feature cannot also be a further development of the invention without the other feature.

[0005] One embodiment relates to a gearbox housing comprising several side walls, wherein at least one of the side walls has one or more housing openings for receiving a bearing, wherein a rib structure tapering vertically above a housing opening in the direction of the housing opening is formed on an inner side of a side wall, wherein a collecting trough is provided into which the tapering rib structure opens and which is formed by a bore passing through the side wall.

[0006] In a typical operating situation, the side walls are oriented vertically. This means that a perpendicular direction, aligned with the plane of the side wall openings, is a horizontal direction. Two horizontally opposing side walls may be provided, each with a funnel-shaped rib structure above its respective opening. The side walls may rest on a base. Footrests may be provided, primarily formed by the base, but extending into the side walls.

[0007] The gearbox housing can accommodate spur gears and / or bevel gears via corresponding shafts. The shafts can be rotatably mounted in bearings located in the housing openings. These housing openings are advantageously designed as round bores. For example, rolling bearings can be used as bearings.

[0008] The gearbox housing can be partially or predominantly made with thin walls, whereby the resulting loss of stiffness is at least compensated for by the rib structure on the inner sides of the side walls. An additional rib structure or ribbing can also be provided to further contribute to the stiffness of the gearbox housing.

[0009] The ribbed structure is formed by a protrusion that rises above the main surface. In a simple embodiment, the ribbed structure can consist of just two ribs tapering vertically downwards towards each other. This funnel-shaped ribbed structure can also be described as V-shaped. It is not essential that the V-shape tapers to a point at the bottom; the lower portion of the ribbed structure can also be rounded. Even a U-shape would be conceivable for certain applications. The ribbed structure allows for the targeted collection of splashed oil and its subsequent delivery to the bearings.

[0010] The collection trough opens essentially vertically upwards. A surface of the collection trough can have the same surface finish as a surface of the bore within the side wall. Preferably, the surface finish of the collection trough and the bore has a significantly lower surface roughness than the adjacent ribbed structure and the inner surface of the side wall. The collected lubricating oil can be gathered outside the side wall via the collection trough and the bore passing through the side wall, and then selectively fed from the outside to the bearing located there.

[0011] According to the invention, the bore, with a section located on the inside of the side wall, forms the collecting trough. This means that the collecting trough is part of the bore. Preferably, the collecting trough is at least partially bounded vertically downwards by the rib structure not encompassed by the bore. This eliminates the need for an undercut in the casting process, as the undercut required for the collecting trough is created by the bore, which leaves the rib structure untouched in an area vertically below and axially extending from the bore.

[0012] In a preferred embodiment, the bore penetrates the side wall in a direction perpendicular to a main plane of the side wall. This is particularly advantageous from a manufacturing perspective, as other bores, for example for screw holes, are also positioned perpendicular to the wall. Therefore, the same tool can be used for both.

[0013] In a preferred embodiment, the collection trough has an undercut when viewed from a perpendicular direction towards the side wall. This prevents the collected splash oil, at least to a large extent, from overflowing into the interior of the gearbox housing.

[0014] In a preferred embodiment, the vertical depth of the collecting trough is between 1 / 3 and 2 / 3 of the bore diameter. This advantageously ensures that the bore can be set within certain tolerances when passing through the side wall. It is particularly preferred if the vertical depth is between 2 / 5 and 3 / 5 of the diameter. From a functional point of view, it is especially preferred if the vertical depth of the collecting trough is half the bore diameter.

[0015] In a further preferred embodiment, the housing opening and the bore are covered by a housing side cover. This side cover creates a secondary volume relative to the actual housing volume. This secondary volume can be used to store oil before it can flow back through the bearing, thus lubricating and cooling it.

[0016] The gearbox housing has a mounting cover, the inner wall of which, in a preferred embodiment, is convex outwards from an inner volume of the gearbox housing. This advantageously ensures that lubricating oil sprayed onto the inner wall of the mounting cover runs towards one of the side walls, where it is collected by the funnel-shaped rib structure on the side walls. In particular, the curvature of the inner wall is designed to run in a vertical plane perpendicular to the side wall.

[0017] The problem is further solved by a method for manufacturing one of the described gearbox housing configurations, in which the funnel-shaped tapered rib structure on the inner side of a side wall is cast without undercuts using a casting process, viewed from a perpendicular direction. The collecting trough is created by drilling a hole in the side wall in a vertically lower region of the rib structure. An advantage of this method is that the rib structure on the inner side of the side wall is cast without undercuts. This facilitates and simplifies the casting process, as no undercutting cores are required and these do not subsequently need to be removed from the undercuts.

[0018] In a preferred embodiment of the method, the bore is positioned from an outer side of the side wall inwards, with the bore centered at the vertical height of a base point of the rib structure. In this context, "centering" refers to the bore's central axis. The base point of the rib structure is formed by the transition from the vertical side wall to the bulge forming the rib structure. Advantageously, this transition lies at the lowest vertical point. The bore is thus positioned with its central axis such that the central axis lies essentially at this base point, or transition between the side wall and the rib structure, and extends substantially half the bore diameter further into the rib structure, while extending half the bore diameter vertically above the rib structure, and thus remaining separate from it.When determining which proportion of the bore diameter runs within the rib structure and which corresponding complementary proportion is free from the rib structure, a deviation from the equal distribution is possible, as described above.

[0019] The problem is further solved by an industrial application comprising a drive means which is connected to a gearbox in a torque-transmitting manner, wherein the gearbox is coupled to a mechanical application in a torque-transmitting manner, and wherein the gearbox is designed with a gearbox housing as described above.

[0020] Furthermore, the task is solved by a data agglomeration with data packages summarized in a common file or distributed across different files to represent the three-dimensional shape design and / or the interactions of a gearbox with a gearbox housing as previously described, wherein the data packages are prepared to enable, when processed by a data processing device, the manufacture of the gearbox housing, in particular by 3D printing using a 3D printer, and / or a simulation of the functionality of the gearbox housing.

[0021] The invention is explained below by way of example with reference to the accompanying drawings and preferred embodiments, wherein the features shown below can represent an aspect of the invention, either individually or in combination. The drawings show: Fig. 1 : a gearbox housing in a vertical section; Fig. 2: another vertical section of the gearbox housing after Figure 1 ; Fig. 3 : a detailing of a rib structure of the gearbox housing according to Figure 1 ; Fig. 4 : a perspective view of the gearbox housing after Figure 1 and Fig. 5 : a basic representation of an industrial application.

[0022] The Figure 1 Figure 1 shows a gearbox housing 10 in a vertical section. The image depicts an inner surface 18 of a side wall 12 of the gearbox housing 10. On the horizontally opposite side, which is not visible due to the section, another side wall is provided. The gearbox housing 10 also includes a base 36 and a cover designed as a removable mounting cover 30. Several round housing openings 14 are provided in the side wall 12 for receiving components located in the Figure 1The gearbox housing 10, which is not shown, can accommodate, for example, a bevel gear drive or a spur gear drive with its corresponding components in a ready-to-use state. Furthermore, the gearbox housing contains a volume of lubricating oil, which provides lubrication for both the meshing gears and the bearings 16 (see [reference]). Figure 2 Lubrication can occur when at least one of the rotating gears immerses in the lubricating oil held in an oil sump at the bottom of the gearbox housing 10, thereby transferring the lubricating oil to the meshing gear(s). As the gears rotate, the lubricating oil is flung off them, so that it condenses as splash oil on the inner walls of the gearbox housing 10 and, following gravity, runs down into the oil sump.

[0023] In the Figure 1It can be seen that the inner surface 18 of the side wall 12 has a structure designed as multiple ribs 20. The rib structure 20 is formed by a projection that stands out from a main surface. In the simplest embodiment, only one rib structure 20 is formed on the inner surface 18 of the side wall 12, which in turn is formed by two ribs 281, 282 that taper vertically downwards towards each other. The funnel-shaped rib structure 20 tapers vertically downwards in an approximately V-shape, whereby the ribs 281, 282 do not necessarily have to meet at a sharp point at the bottom. A short horizontal connecting area between the ribs 281, 282 can also be provided. In all conceivable embodiments, the funnel-shaped rib structure 20 terminates in a collecting trough 22. The collecting trough 22 serves to collect oil.In particular, oil collects in the collection trough 22, running down the side wall 12 within the ribbed structure 20 from above. The ribbed structure 20 and the collection trough 22 are positioned approximately centrally above the housing opening 14 of the side wall 12.

[0024] The Figure 2 shows one opposite Figure 1A vertical section through the gearbox housing 10, rotated by 90°, is shown, with the right side wall not depicted. The left side wall 12 is visible, with a bearing 16 accommodated in the housing opening 14. In this case, the bearing 16 comprises a tapered roller bearing, which will not be discussed in detail here. Other bearing types may also be used. The housing opening 14 is closed with a housing side cover 26, which may, for example, be held against the side wall 18 by circumferential screws. Within the housing side cover 26, a secondary volume 38 is formed opposite the side wall 12, and this secondary volume 38 is open to the bearing 16 located in the housing opening 14. The vertical section of the Figure 2The bore 24 is positioned such that it runs centrally through the ribbed structure 20 located above the housing opening 14 and the collecting basin 22. A bore 24 is also visible, which passes through the side wall 12 and forms the collecting basin 22 in the lower region of the ribbed structure 20. On the outside of the side wall 12, the bore 24 opens within the secondary volume 38 enclosed by the housing side cover 26. The collecting basin 22 formed by the bore 24 inside the gearbox housing 10 is connected to the secondary volume 38 via the further course of the bore 24 within the side wall 12. Lubricating oil that collects in the collecting basin 22 can therefore reach the secondary volume 38 via the further course of the bore 24 in the side wall 12. From the secondary volume 38, the lubricating oil can flow into and through the bearing 16.

[0025] The mounting cover 30 of the gearbox housing 10 is shaped such that an inner wall 32 of the mounting cover 30 is convex outwards from an inner volume of the gearbox housing 10. The curvature 34 of the inner wall 32 runs in a vertically oriented section plane perpendicular to the side wall 12, as shown in the Figure 2 has been laid.

[0026] The Figure 3Figure 1 shows a detailed view of the rib structure 20 and the bore 24 passing through the side wall 12, forming the collecting trough 22 on the inside. The bore 24 extends horizontally through the side wall 12. This is easy to achieve from a manufacturing perspective, as most machining steps on the gearbox housing 12 are performed in mutually orthogonal directions anyway. Viewed from a perpendicular direction onto the side wall 12, the collecting trough 22 has an undercut. This undercut, however, is not a result of the casting process, for example, by the use of a corresponding casting core, but rather is the result of the drilling process of bore 24, which was carried out from the outside inwards through the side wall 12 and in which the lower part of the rib structure 20 was not completely penetrated. The diameter of bore 24 is shown in the figure 1. Figure 3The diameter DB is denoted by the diameter of the collection trough 22. Similarly, the vertical depth TM of the collection trough 22 extends from the bottom of the collection trough 22 to the height of the undercutting rib structure 20. In this case, the ratio of the diameter DB of the bore 24 to the depth TM of the collection trough 22 is such that the depth TM is essentially half the diameter DB. It has already been described that this ratio can also be adjusted if this is advantageous for a particular application.

[0027] In the Figure 4 A gearbox housing 10 is shown in perspective view. The front housing side cover 26 and the mounting cover 30 are hidden. Above the right housing opening 14, the bore 24 can be seen, which forms the collecting trough 22 in the base of the rib structure 20 on the inside of the side wall 12.

[0028] One embodiment of an industrial application 40 is in Fig. 5 The industrial application 40 comprises a drive element 42, which is designed, for example, as an electric motor, an internal combustion engine, or a hydraulic motor. The drive element 42 is coupled to a gearbox 44 for torque transmission, which in turn is connected to a mechanical application 46. The drive element 42 is designed to deliver drive power, which is supplied to the gearbox 44 via a power shaft 48. The gearbox 44 converts the incoming drive power, taking into account friction losses, into speed and torque, and transmits the output power via a power shaft 50 to the mechanical application 46. Reference symbol list

[0029] 10 Gearbox housing 12 Side wall 14 Housing opening 16 Bearing 18 Inside 20 Rib structure 22 Collector trough 24 Bore 26 Housing side cover 28 Rib 30 Mounting cover 32 Inner wall 34 Curvature 36 Bottom 38 Secondary volume 40 Industrial application 42 Drive mechanism 44 Gearbox 46 Mechanical application 48 Power shaft 50 Power shaft

Claims

1. Transmission housing (10) comprising a plurality of side walls (12), wherein at least one of the side walls (12) has one or more housing openings (14) for accommodating a bearing (16), wherein a rib structure (20) which tapers in a funnel shape vertically above one of the housing openings (14) in the direction of the housing opening (14) is formed on an inner side (18) of one of the side walls (12), wherein a collecting pan (22) is provided into which the rib structure (20) which tapers in a funnel shape opens, characterized in that the collecting pan (22) is formed by a drill hole (24) traversing the side wall (12) and the drill hole (24) forms the collecting pan (22) with a portion situated on the inner side (18) of the side wall (12).

2. Transmission housing (10) according to Claim 1, characterized in that the collecting pan (22) is delimited at least partially by the rib structure (20) not included by the drill hole (24).

3. Transmission housing (10) according to one of Claims 1 to 2, characterized in that the drill hole (24) traverses the side wall (12) in a direction perpendicular to a main plane of the side wall (12).

4. Transmission housing (10) according to one of Claims 1 to 3, characterized in that the collecting pan (22) has an undercut (52), considered from a direction perpendicular to the side wall (12), and the undercut (52) is formed by a part of the rib structure (20) not included by the drill hole (24).

5. Transmission housing (10) according to one of Claims 1 to 4, characterized in that a vertical depth (TM) of the collecting pan (22) is between 1 / 3 and 2 / 3 of a diameter (DB) of the drill hole (24).

6. Transmission housing (10) according to Claim 5, characterized in that the vertical depth (TM) is between 2 / 5 and 3 / 5, preferably ½, of the diameter (DB).

7. Transmission housing (10) according to one of Claims 1 to 6, characterized in that the housing opening (14) and the drill hole (24) are covered by a housing side cover (26).

8. Transmission housing (10) according to one of Claims 1 to 7, characterized in that the rib structure (20) is formed by at least two ribs (281, 282) which taper vertically downwards towards each other.

9. Transmission housing (10) according to one of Claims 1 to 8, characterized in that a mounting cover (30) is provided, the inner wall (32) of which is bulged outwards starting from an internal volume of the transmission housing (10).

10. Transmission housing (10) according to Claim 9, characterized in that the bulge (34) of the inner wall (32) extends within a vertical plane of section extending perpendicular to the side wall (12).

11. Transmission housing (10) according to one of Claims 1 to 10, characterized in that two side walls (12) situated horizontally opposite each other are provided with rib structures (20) which taper in a funnel shape above a respective housing opening (14) in the direction of the housing opening (14).

12. Method for producing a transmission housing (10) according to one of Claims 1 to 11, in which the rib structure (20) which tapers in a funnel shape is cast, via a casting process, with no undercuts on an inner side (18) of a side wall (12), considered from a direction perpendicular to the side wall (12), and characterized in that the collecting pan (22) is produced by making the drill hole (24) in the side wall (12) in a vertically lower region of the rib structure (20).

13. Method according to Claim 12, in which the drill hole (24) is made inwards from an outer side of the side wall (12), wherein a centre of the drill hole (24) lies at the vertical height of a foot of the rib structure (20).

14. Industrial application (40) comprising a drive means (42) which is connected in a torque-transmitting fashion to a transmission (44), wherein the transmission (44) is coupled in a torque-transmitting fashion to a mechanical application (46), characterized in that the transmission (44) is formed with a transmission housing (10) according to one of Claims 1 to 11.