Cooling module for a gearbox and modular system for gearbox cooling devices

Abstract

Cooling module (29) for a gearbox (40), wherein the cooling module (29) comprises a cast part (30) in which a space (34) for flowing coolant, in particular air or water, is provided, wherein cooling fins (32) and / or cooling fingers directed into the interior of the gearbox are attached to the casting (30), wherein the outer edge of the cooling fins (32) and / or the ends of the cooling fingers follow the shape of a rotating part (45) or several rotating parts (45, 46) of the gear (40), wherein the cooling module (29) can close an opening (47) in the gear housing (41) of the gear (40), the edge of which opening defines a minimum area through which the cooling fins (32) and / or cooling fingers protrude into the interior of the gear (40), so that two spatial areas are present, namely the first spatial area (34) for a flowing coolant and a second spatial area located inside the gearbox for the contact of the cooling fins (32) or cooling fingers with lubricating oil flowing in the gearbox housing (41), characterized by that the cooling fins (32) and / or cooling fingers are hollow to accommodate a coolant.

Description

[0001] The invention relates to a cooling module for a transmission and a modular system for transmission cooling devices.

[0002] From DE 40 29 641 A1 a housing of a gear change transmission is known in which a cover is designed as an oil / air heat exchanger.

[0003] From EP 0 853 225 A2 a cooler for the oil in the housing of a gearbox is known, in which the housing of a heat exchanger can be inserted as a cover into an opening of the gearbox housing, wherein the wall of the heat exchanger housing facing the interior of the gearbox housing forms the heat exchanger plate.

[0004] From DE 10 2004 022 863 A1 a gearbox and a modular system of gearboxes are known in which a cover of the gearbox housing has outwardly projecting cooling fingers, which are referred to there as a cooling device.

[0005] The invention is based on the object of developing a transmission in such a way that the transmission cooling is improved.

[0006] According to the invention, the object is achieved in the cooling module for a transmission according to the features specified in claim 1 and in the modular system for transmission cooling devices according to the features specified in claim 3.

[0007] Features of the invention in the cooling module for a transmission are that the shape of the cooling module facing the transmission interior follows the shape of one or more rotating parts of the transmission. This is advantageous in that an improvement in heat dissipation from the transmission interior can be provided by means of an enlarged surface in the spatial area of ​​the oil flow between the part or parts and the surface in the spatial area of ​​the oil flow between the part or parts and the housing. This allows for better utilization of the interior of the transmission by a cooling device. This is because the oil flow within the transmission can be directed past the surface of the cooling module that is enlarged by the shape projecting into the transmission interior. This allows a smaller distance between the heat source and the cooling module surface, and heat transfer is improved. Furthermore, the oil flow is more effectively utilized.This is because the majority of the oil flow is now conductive in such a way that it comes into contact with the surface for heat dissipation. In particular, the formation can advantageously be brought so close to the gearing components that only insignificant portions of the oil flow are lost for heat dissipation to the cooling module. Furthermore, a lubricant with a higher viscosity than oil, such as lubricating grease or grease, can be used. Such a lubricant adheres at least partially to the gearing component as long as the temperature of the transmission is low. Using the invention, the formations brought closer can still come into contact with this lubricant portion.

[0008] According to the invention, the cooling module comprises a cast part, wherein a space for flowing coolant, in particular oil, air, or water, is provided in the cast part, and wherein cooling fins and / or cooling fingers directed into the interior of the transmission are attached to the cast part, in particular formed integrally with the cast part or welded to the cast part. The cooling module thus has a thickness that varies in the longitudinal direction of the cast part. It is advantageous that two separate space areas can be provided: a first for a flowing coolant, for example, air, water, or oil, and a second, located inside the transmission, for the contact of cooling fins or cooling fingers with oil flowing in the transmission housing, i.e., lubricating oil. Thus, a thick metal part can advantageously be provided as a cast part, whereby the cooling module is robust against mechanical stresses.Another advantage is that the separation of the two compartments provides redundant protection against mixing of coolant and lubricating oil. Even if a seal in the coolant compartment were to leak, the coolant would not be able to enter the gearbox interior, but would flow outside the gearbox interior, which is sealed off by the cast part.

[0009] In an advantageous embodiment, the shape of the cooling module facing the interior of the gearbox follows the shape of a rotating part or several rotating parts of the gearbox in such a way that heat can be transported away from the spatial area, in particular substantially from the entire spatial area, of the oil flow between the part or parts and the housing. Thus, to improve heat dissipation from the oil to the gearbox environment, heat can advantageously be absorbed by the shape in spatial areas of the oil flow. Following the shape of a rotating part of the gearbox is particularly advantageously achieved if a concentric circle or a concentric ellipse with small eccentricity can be drawn around the rotating part, which has points in common with the mathematically idealized surface of the shape, but which does not intersect the mathematical interior of the shape.The shape of the recess, and thus also the following of the shape of the rotating part, is advantageously designed such that the lubricant or oil flow generated by the rotating part for heat dissipation can be brought into contact with the surface of the recess as completely as possible. The flow resistance for the flow should be kept low.

[0010] In a further advantageous embodiment, the shape of the formation is selected such that, on the one hand, the gears or toothed parts, for example cyclo disks or eccentric disks, of the gearbox for the various gear ratios with which the gearbox can be equipped, are not hindered in their intended movement by the formation, and on the other hand, the formation follows as closely as possible, at least partially, the area swept over by the rotating parts, in particular the gears, in order to be able to easily absorb oil thrown off by the rotating parts, in particular the gears. It is advantageous in this case that the distance of the formation to one or more rotating parts is as small as possible. The minimum distance of the formation to the rotating parts is mainly determined by the manufacturing tolerances of the gearbox housing and the cooling module.For gearboxes with low power transmission, the distance from the rotating parts can also be advantageously selected to ensure that the gearbox's efficiency is not significantly reduced by friction between the oil and the rotating parts, which is particularly common during start-up at low temperatures due to oil clogging. This is advantageous because a series of gearboxes, whose variants differ only in the selection of gear ratios, can be equipped with a uniform cooling module.

[0011] In a further advantageous embodiment, the interface for the tightly sealing connection of the cooling module to the gearbox comprises a seal, wherein in particular the formation projects through the minimal surface bordered by the seal into the interior of the gearbox. The minimal surface bordered by the seal serves to separate the interior and exterior of the gearbox housing with respect to the opening belonging to the interface. The minimal surface is created by reducing the seal to an idealized closed line that runs around and thus describes the opening, and by inserting a section of a soap bubble into the line, the edge of which is formed by the closed line and which is otherwise left to itself. The cooling module can therefore generally be used to close off a recess, in particular an opening, in the gearbox housing, the edge of which delimits a minimal surface through which the formation projects into the interior of the gearbox.Thus, the interior of the gearbox, which is adjacent to the interface, is advantageously used by the cooling module to absorb heat.

[0012] In a further advantageous embodiment, the formation comprises ribs which in particular have slot-shaped interruptions, wherein the outer edge of the ribs follows the shape of one or more rotating parts of the transmission. The ribs thus advantageously form surfaces which, on the one hand, guide the oil flow and, on the other hand, absorb heat from the oil flow. The spacing of the ribs from one another can advantageously be selected to be minimal, depending on the viscosity of the lubricating oil, such that the oil flows in the spaces between the ribs with low flow resistance. The spacing of the ribs and the thickness of the ribs are particularly advantageously determined by the intended manufacturing process.

[0013] In a further advantageous embodiment, the formation comprises a plurality of fingers, wherein the ends of the fingers lie on an imaginary, mathematical line or surface that follows the shape of one or more rotating parts of the transmission. By designing the formation as fingers, which preferably have a round cross-section transverse to their longitudinal direction, it is advantageously achieved compared to the design as ribs that flowing, splashing, or centrifuged oil can be absorbed from more than one direction. This further improves the heat transfer from the oil to the cooling module, particularly when the transmission is used in a less favorable position in which the oil flow does not follow the direction of the ribs due to the position.The distance between the fingers can be advantageously selected according to the viscosity of the lubricating oil so that the oil flows in the spaces between the ribs with little flow resistance.

[0014] According to the invention, the fins and / or fingers are hollow to accommodate a coolant, particularly water. The advantage here is that, by placing a suitably shaped cover, the fins form channels through which a coolant, such as water, flows particularly close to the oil flow, thus further improving heat dissipation to the environment.

[0015] In a further advantageous embodiment, the shape of a rotating part of the transmission follows at least one imaginary circular arc, wherein in particular the radius of the circular arc is determined by the radius of the rotating part, and / or the shape extends into areas adjacent to the side surfaces of gears of the transmission. This advantageously allows for particularly effective absorption of the oil flow and particularly good utilization of the transmission's interior space.

[0016] In a further advantageous embodiment, the cooling module is made of aluminum, steel, copper, or a metallic alloy, in particular by die casting or sand casting, and / or the molding is integrally connected to the cooling module, in particular by bonding or welding. This advantageously allows for cost-effective, uncomplicated production of the cooling module.

[0017] In a further advantageous embodiment, the shape of the cross-sectional area of ​​the fingers, i.e., the cut surface transverse to the longitudinal direction of the fingers, is based on the symmetry of the arrangement of the fingers on the cooling module, wherein the fingers are manufactured in particular by a machining process, in particular milling. This advantageously enables cost-effective, simple production of the ribs with little effort. Depending on the type of symmetry, i.e., the number of discrete rotational symmetry, which, in the case of idealized, hypothetical infinite extension, transforms the arrangement grid for the fingers into itself, triangular, quadrangular, or polygonal cross-sections can advantageously be provided.

[0018] In a further advantageous embodiment, the cooling module for a gearbox can be placed onto the gearbox housing as a cover for closing an opening in the gearbox housing, wherein the cooling module is designed as a cast part and has a groove on its outer side. The cooling module can be provided particularly advantageously for closing the assembly opening through which the toothed parts can be introduced into the interior of the gearbox during gearbox assembly. The cast part has connection devices for a cooling circuit, and the ends of the groove are connected to the connection devices. The groove can advantageously be designed in a meandering manner. This allows for an external cooling circuit for water or another coolant to be provided, which can be safely separated from the gearbox interior. The safe separation is based on the cooling circuit being closed off to the outside using means that are different and spatially separate from the means for closing off the gearbox interior.This is particularly advantageous because it is essential to prevent water from entering the gearbox interior and mixing with oil.

[0019] In a further advantageous embodiment, the bottom of the groove has elevations, in particular cushion-shaped and / or wave-shaped and / or regularly spaced elevations. The elevations cause a change in the groove depth in the direction of the groove, i.e. along the groove. The advantage here is that the elevations force a turbulent flow of the coolant even at relatively low flow velocities, at which the coolant would flow laminarly, especially without elevations. As a result, the coolant flow has a more uniform temperature distribution than would be the case with laminar flow. Thus, improved heat dissipation can be achieved with the same coolant throughput. This saves coolant and energy and consequently costs.

[0020] In a further advantageous embodiment, the transmission housing comprises a housing interface for closing an opening with a cover, wherein the cooling module has an external connection interface on its side facing away from the transmission, wherein the external connection interface and the housing interface are of the same type, in particular identical, and in particular have the same shape. By designing and using interfaces for mechanical connection, a large number of cooling devices can be assembled from a small number of individual parts. This advantageously saves storage and construction costs. The term interface is generally understood here to mean a list of features and / or means which are provided correspondingly on two parts and / or between two parts in order to ensure that these parts are joined and / or connected in a defined manner.

[0021] In a further advantageous embodiment, the housing interface and the external connection interface each comprise sealing means. Thus, the function of a tight connection is advantageously integrated into the connection interface. The sealing means serve to seal the interior of the gearbox housing against dust, dirt, water, and possibly air, shield the area surrounding the gearbox from oil, and possibly prevent the leakage of coolant, in particular the mixing of coolant with oil inside the gearbox housing. These sealing means are preferably designed as O-rings or elastomer surfaces or adhesive bonds.

[0022] In a further advantageous embodiment, the cooling module has an inner connection interface on its side facing the transmission, wherein the inner connection interface and the outer connection interface are of the same type, in particular identical, and in particular have the same shape. This advantageously simplifies processing steps during the production of the cooling modules.

[0023] In a further advantageous embodiment, the cooling module is made of aluminum or steel or a metallic alloy, for example, stainless steel, in particular by die casting or sand casting, and / or the molding is integrally connected to the cooling module, in particular by gluing or welding. It is advantageous in this case to use materials that allow for simple and cost-effective production in accordance with the requirements. These requirements include, in particular, mechanical stability with respect to the loads to which the gearbox is exposed during operation, weight, thermal resilience at temperatures of 100°C and higher, and chemical resistance to the coolant.

[0024] Features of the invention in the transmission with a cooling device are that the transmission housing has an opening that can be closed with a cover, wherein the cooling device comprises a cooling module, and wherein the cooling module is spatially arranged between the housing and the cover and closes the opening. The advantage here is that a cooling device can be retrofitted to a transmission simply, flexibly and cost-effectively, wherein in particular the cover of the opening to which the cooling device is attached is reused on the cooling device. This saves costs during retrofitting. In particular, a separate area on the transmission housing for attaching a cooling device is advantageously dispensable, since an opening that can be closed with a cover is provided on the transmission housing anyway, for example for assembly or maintenance purposes, and can be used according to the invention.

[0025] Features of the invention in the modular system for transmission cooling devices are that the modular system comprises modules and covers, each of which can be placed onto a housing interface of a transmission housing to close an opening, wherein the modules and covers have an inner connection interface that fits onto the housing interface of the opening of the transmission housing, and the modules have an outer connection interface, wherein the outer connection interface and the housing interface are of similar type, in particular identical, and in particular have the same shape. The described design of the parts of the modular system with matching interfaces advantageously results in a wide range of possible combinations and thus a wide variety of cooling device variants while at the same time requiring a small number of individual parts.In addition, a simple and flexible retrofitting of a gearbox without a cooler or with an inadequately dimensioned cooler is possible easily and cost-effectively.

[0026] Another advantage is that an opening already provided on the gearbox housing can be utilized. Monobloc gearbox housings, i.e., those made from a single casting, are particularly suitable, as such housings have an opening for inserting the gears or gear components inside. The size of the opening is determined at least by the size of the largest gear component intended for installation.

[0027] In an advantageous embodiment, the outer and inner connecting interfaces each comprise at least one drilling pattern and / or sealing means and / or formations for sealing and / or centering means. It is therefore advantageous that the connection of the interfaces can be provided by means of screws and / or clamping elements and / or locking connecting elements and / or that the connection of all modules and covers selected for a transmission cooling device can be established with the same set of fastening means, such as screws, rivets or clamping elements. The use of screws and / or clamping elements advantageously ensures that the connections can be released quickly. The drilling patterns and / or the formations for sealing, such as tongue and groove systems, and / or the centering means advantageously enable quick and error-free installation.

[0028] In a further advantageous embodiment, the outer and inner connection interfaces are designed in a similar manner, in particular identically. This advantageously reduces the number of different manufacturing steps. Furthermore, a high degree of variation within the series can be achieved with a small number of parts.

[0029] In a further advantageous embodiment, at least one cover is made of steel or a metallic alloy, for example, stainless steel, and / or is provided with a corrosion-resistant and / or coolant-resistant coating. This is advantageous because a cost-effective cover is provided in the modular system, for example, for use on a transmission housing without a cooling device. The corrosion-resistant and / or coolant-resistant coating also advantageously allows the cover to be brought into contact with a coolant circuit without being damaged by chemical reactions. The cover is advantageously coated with a corrosion-protective paint or an elastomer.

[0030] In a further advantageous embodiment, the corrosion- and / or coolant-resistant coating has a sealant at at least one of the connection interfaces. Advantageously, the coating and sealant can be applied in a single operation. The sealants advantageously comprise linear or surface-formed seals and / or tongue-and-groove systems.

[0031] In a further advantageous embodiment, at least one module has a groove on its outward-facing side, wherein means are provided in particular for connecting the groove to a cooling circuit, wherein the cooling circuit is arranged in the transmission housing or outside the transmission housing, and wherein the coolant is oil, water, or another coolant. The cooling device can thus be easily connected to a cooling circuit, in particular while maintaining the tight closure of the transmission housing. A particular advantage here is that a connection for the cooling circuit can already be provided in the module, thus eliminating the need for a modified cover with such connection devices.

[0032] In a further advantageous embodiment, at least one module has a recess on its inward-facing side that follows the shape of one or more rotating parts of the transmission. This advantageously allows the interior of the transmission housing to be used for cooling, and allows oil thrown or flowing away from rotating parts to be captured by the cooling device, in particular the recess, thereby allowing heat to be extracted from the oil.

[0033] In a further advantageous embodiment, the transmission cooling devices can be used in a series of transmissions that differ in terms of their respective gear ratios due to the selection of the gears provided. This advantageously combines the advantages of a modular system for transmission cooling devices with the advantages of a modular system for transmissions – in which, in particular, parts of the transmission housing, for example, the housing interface, are designed identically in all variants, while the geared parts used to achieve different gear ratios and / or torque deflection angles differ.

[0034] In a further advantageous embodiment, at least one cover has a protrusion, in particular ribs and / or fingers, on its outward-facing side. This advantageously allows for a passive cooling device to be formed within the modular system, i.e., one that can be operated in particular without a coolant circuit. Alternatively, air cooling can also be provided, in which air driven by a fan flows past the outward-facing protrusion.

[0035] According to the invention, the kit comprises at least one cooling module according to the invention. The advantage here is that the advantages of the cooling modules according to the invention can be utilized in the cooling devices that can be formed with the kit.

[0036] In a further advantageous embodiment, at least one module has a hollow shape on its inward-facing side, and at least one cover has a shape corresponding to the hollow profile on its inward-facing side, so that the shape of the cover fits at least partially into the hollow shape of the module. Advantageously, the hollow shape of the module and the shape of the cover can form a channel through which coolant can be conducted, allowing the coolant to be brought particularly close to the spatial regions in which the oil to be cooled flows.

[0037] In a further advantageous embodiment, the kit includes an air guiding device that allows air from a fan to be directed over the transmission cooling device. This is advantageous because a fan, for example, a passive fan arranged on an input shaft, can be used with parts of the kit for the cooling device.

[0038] In one design of the series, at least one passive cooling module with fins and / or fins on the inside and outside is made in one piece, i.e. from a single casting.

[0039] Features of the invention in the series of gearboxes are that the series comprises variants which differ in the different gears and / or toothed parts used, in particular with regard to the gear ratio, wherein a gearbox cooling device is provided, the cooling module of which follows the shape of a toothed part in a first variant in the series, in particular within the framework of the manufacturing tolerances, and approximately follows the shape of a toothed part in a second variant in the series.The advantage here is that the variety of parts in the modular system that defines the gearbox series can be reduced, since cooling modules designed for one variant of the series, whose structural dimensions, particularly with regard to the ribs or fingers protruding into the interior of the gearbox, can be provided for other variants in which they do not fit optimally, since significant cooling effects can therefore also be achieved for these, even though the shapes of the rotating parts in these other variants only approximately follow and with deviations due to the different types of gearing. A gearbox in this series is generally understood to be a device for deflecting or transmitting torque. Gears are arranged in a gearbox, with meshing gears forming a gear stage. The gear stages used determine the overall gear ratio.The gears provided for the gear stages at a given gear ratio are collectively referred to as a gear set. This series of gears is advantageously characterized by the fact that different gear sets can be provided for one gear housing, creating transmission variants with different gear ratios. The series is advantageously designed so that the parts of the cooling device fit different gear sets, with one cooling module better following the shape of one gear set than the shape of another.

[0040] The invention will now be explained in more detail with the aid of illustrations:

[0041] It shows Fig. 1a an embodiment of a cooling module, Fig. 1b the embodiment of Fig. 1a, seen from below, Fig. 1c a longitudinal section through the embodiment of Fig. 1a, Fig. 1d a cross section through the embodiment of Fig. 1a, Fig. 2a a second embodiment of a cooling module, Fig. 2b the embodiment of Fig. 2a, seen from below, Fig. 2c a longitudinal section through the embodiment of Fig. 2a, Fig. 3a a cross section and Fig. 3b a longitudinal section through an embodiment of a cooling module according to the invention, Fig. 4a the inventive use on a gearbox of a cooling module from the modular system according to the invention, Fig. 4b the inventive use of a further cooling module from the modular system according to the invention, Fig. 4c the inventive use of a further cooling module from the modular system according to the invention, Fig. 4d the inventive use of a further cooling module from the modular system according to the invention, Fig. 5a the gearbox with cooling module Fig. 4d in assembled form, Fig. 5b a longitudinal section through the gearbox with cooling module from Fig. 5a, Fig. 6 a side view and a cross section of the cooling module from Fig. 4b in assembled form, Fig. 7 a cross-section of the cooling module Fig. 4c in assembled form.

[0042] Fig. Figure 1a shows an embodiment of a first cooling module. The first cooling module 1 consists of a module plate 2, on the underside of which a recess is provided, which is designed as a plurality of parallel catching ribs 3.

[0043] In Fig. Figure 1b shows the first cooling module from below. The parallel ribs 3 have a thickness that tapers away from the module plate 2. The ribs 3 are congruent with each other and are made of aluminum from a single casting, particularly by sand casting or die casting.

[0044] In another embodiment, the catch ribs 3 are manufactured separately from flat aluminum material and then connected by welding to the module plate 2, which is also made of aluminum.

[0045] In a further embodiment, the catching ribs 3 and the module plate 2 are made of a metallic alloy, for example of steel or copper or of alloys of both.

[0046] In the Fig. A meandering coolant groove 9 is provided on the top side of the module plate 2 shown in Figure 1a. The bottom of this coolant groove 9 has groove bottom elevations 12.

[0047] On one short side of the module plate 2, two connection openings 10 are provided, each of which opens into a groove end 11 of the coolant groove 9.

[0048] Fig. Figure 1c shows a longitudinal section through the first cooling module 1. The section plane intersects the side surface of a retaining rib 3 approximately at mid-height. The retaining rib 3 has three circular indentations 4, 5, and 6, which are separated from one another by the circular intersection points 7 and 8. The radii of the circular indentations 4, 5, and 6 and the depth of their indentation into the retaining rib 3 are determined by the structural and geometric conditions at the location of use of the first cooling module on a transmission, in particular by the radius and position of the gears of the transmission. The three-part design shown advantageously ensures that the cooling module can be used for different gear sets in the same transmission housing.

[0049] In other embodiments, two or fewer or more than three circular bulges are provided, which are divided by circular intersection points.

[0050] In other embodiments, slot-shaped interruptions are provided on the catch ribs 3, extending away from the module plate 2.

[0051] Fig. 1c also shows a section of the coolant groove 9 with the groove bottom elevations 12. These groove bottom elevations 12 are designed as rounded, cushion-shaped steps, with the steps being arranged at equal intervals on the groove bottom.

[0052] In other embodiments, the groove bottom is wave-shaped and / or the elevations are arranged at regular or irregular intervals, or the groove bottom is flat and thus designed without elevations.

[0053] The groove bottom elevations cause a liquid flowing in the coolant groove 9, such as a coolant, to assume a turbulent flow behavior and thus have good mixing, particularly with regard to the temperature distribution in the liquid.

[0054] A passage 17 connects the Fig. 1c with the adjacent section of the coolant groove 9.

[0055] Fig. Figure 1d shows a cross-section through the first cooling module 1, on which a gear cover 49 is mounted. By placing the gear cover, the coolant groove 9 forms a closed, meandering channel through which coolant can flow and which is connected to the outside only via the connection openings 10.

[0056] The catching ribs 3 define collecting spaces 14 through which oil flung from the gear stages or gearwheels can be collected when the cooling module is used according to the invention on a transmission. The spacing of the catching ribs from one another is advantageously selected such that the collecting spaces 14 formed by the catching ribs 3 each have a cross-section approximately as large as the cross-section of a catching rib 3. The inclination of the side surfaces of the catching ribs 3 relative to the module plate 2, the thickness of the catching ribs, and the spacing between the catching ribs are advantageously selected according to the specifications of the manufacturing process, such as sand casting or die casting.

[0057] In further embodiments according to the invention, the distance between the ribs is smaller or larger than the thickness of the catching ribs.

[0058] Fig. Figure 2a shows another embodiment of a second cooling module. The second cooling module 19 consists of a module plate 2, which has a recess in the form of catch fingers 20 on its underside.

[0059] The module plate 2 has a coolant groove 9 and connection openings 10 and is identical in construction to the module plate of Fig. 1a to 1d. This enables cost-effective production of cooling modules in various variants, with catching ribs and / or with catching fingers.

[0060] The second cooling module 19 is manufactured using the aluminum casting process.

[0061] Fig. 2b shows the underside of the second cooling module 19. The catching fingers 20 are arranged in parallel longitudinal and transverse rows so that continuous, parallel lanes are formed in at least two directions.

[0062] In other embodiments, the catching fingers are arranged in other regular or irregular patterns.

[0063] The catching fingers 20 define collecting areas 21 through which, when the second cooling module is used according to the invention on a transmission, oil thrown away from its gear stages or gearwheels in various directions, in particular diagonally or perpendicularly to one another, can be collected. This is advantageous compared to the embodiment according to Fig. 1a, in which the collecting areas 14 characterize a single direction.

[0064] The catching fingers 20 have a round cross-section in relation to their length and they taper towards their end.

[0065] In other embodiments, the catch fingers have a polygonal cross-section, particularly a triangle or quadrilateral. The shape of the cross-sectional area is advantageously based on the symmetry of the arrangement of the catch fingers on the module plate. Thus, the catch fingers can be manufactured from a single block together with the module plate using simple, inexpensive separation processes.

[0066] Fig. 2c shows a longitudinal section through the Fig. 2a. The ends of the catching fingers 20 form an envelope in the longitudinal direction of the second cooling module 19, which describes three circular indentations. These circular indentations merge into one another at imaginary circular intersection points 22, 23. The radii of the circular indentations and the depth of their indentation into the plane spanned by the catching fingers are determined by the structural and geometric conditions at the location where the second cooling module is used on a transmission, in particular by the radius and position of the rotating parts of the transmission, such as gears, cyclo disks, eccentric disks, or the like.

[0067] In other embodiments, two or fewer or more than three circular bulges are provided, which are divided by circular intersection points.

[0068] Fig. 3a shows a cross section and Fig. 3b a longitudinal section along the section AA through an embodiment of a third cooling module according to the invention.

[0069] The third cooling module 29 consists of a module lower part 30 and a module upper part 31. The module lower part 30 comprises a plate and hollow ribs 32 running parallel to one another, in which corresponding solid ribs 33 of the module upper part 31 are arranged when the module upper part 31 is placed on the module lower part 30 in the manner shown.

[0070] The longitudinal profile of the hollow ribs 32 according to Fig. 3b describes an envelope corresponding to that of the catching ribs of the first cooling module 1 from Fig. 1c is similar.

[0071] The hollow ribs 32 and the solid ribs 33 form in the assembled position, as in Fig. 3b, each has a coolant channel 34. These coolant channels 34 are connected via passages 35 to form a meandering coolant channel in two directions. The ends of the meandering coolant channel open to the outside via two connection openings 36.

[0072] Fig. 4a shows an inventive use of a first cooling module according to Fig. 1a to 1d in a gearbox 40, which comprises a housing 41 in monobloc construction, i.e., made from a single cast, with an opening 47. Gears 45 are arranged on shafts in the housing 41. These gears 45 are accessible via the opening 47 for the purpose of assembly, inspection, maintenance, or oil replacement. In particular, the opening is dimensioned such that the largest gear or toothed part provided can be passed through it. Thus, the gearbox in which the cooling module 1 is used advantageously determines the structural dimensions of the opening 47 and thus of the cooling module 1. The length of the opening 47 is approximately 30 cm in the exemplary embodiment described here. In other exemplary embodiments, this length is between 5 cm and 2 m.

[0073] In Fig. 4a, a shaft is further mounted as input shaft 42 via a bearing in the housing 41, a cover 43 covers the end of the output shaft of the gearbox, which is led out of the housing 41 on the rear side, not shown.

[0074] In a first variant, the opening 47 can be closed with a housing cover 49, which is fastened by screws 52 that are screwed into threaded holes 57. In the fastened position, the housing cover 49 rests flat on the housing flange surface 51. Sealing means (not shown) are provided between the housing flange surface 51 and the housing cover 49, which seal the interior of the housing 41 to the inside and outside, so that no oil can escape and no external contaminants can enter the oil. The seal is advantageously achieved by means of a metal adhesive, for example Loctite®, which is applied to the flange surfaces.

[0075] In other embodiments, the seal is provided by an O-ring or paper gasket running around the flange surface. Such a seal can be improved by a tongue-and-groove system provided on the flange surfaces.

[0076] In a second variant, as exemplified in Fig. 4a - to improve the cooling of the transmission 40, a first cooling module 1 can be provided according to the invention between the housing flange surface 51 and the housing cover 49. For this purpose, the underside of the module plate 2 of the cooling module 1 is placed onto the housing flange surface 51. The module plate 2 has drilled holes 58 whose arrangement and diameter match the threaded holes 57. Thus, the housing cover 49, together with the first cooling module 1, can be fastened to the transmission housing 41 via the screws 52 by inserting the screws 52 through the drilled holes 58 and screwing them into the threaded holes 57. A module flange surface 53 is provided on the upper side of the module plate 2, which, together with the housing cover 49, forms a tight seal for the interior of the transmission housing 41. The necessary sealing means are not shown for the sake of simplicity. Likewise, the underside of the module plate 2 with the housing flange surface 51 forms a tight seal of the interior.

[0077] By placing the housing cover 49 in place, the coolant groove 9 in the module plate 2 is sealed off from the outside in such a way that coolant, for example a cooling liquid such as water or oil, can flow in the channel thus formed without leaking out. The sealing means required for this are not shown for the sake of simplicity. They are preferably provided on the surface of the module plate 2, but can also be provided at least partially on the underside of the housing cover 49. Coolant flows from a coolant circuit into the coolant groove 9 through a first connection coupling 55, and coolant flows from the coolant groove 9 back into the coolant circuit through a second connection coupling 55.

[0078] The housing cover 49 is advantageously made of aluminum. In further embodiments according to the invention, the housing cover is made of steel or stainless steel and / or has a corrosion-resistant and / or coolant-resistant coating, for example a paint or a plastic coating, at least on its side facing the coolant groove. In a further embodiment according to the invention, the plastic coating additionally seals the connection between the housing cover and the cooling module.

[0079] It is particularly advantageous when Fig. 4a, that even in the event of a leak in the coolant lines or in the event of a leak in the seal between the housing cover 49 and the module plate 2, no coolant can enter the interior of the housing 41.

[0080] In the mounted position, the catching ribs 3 of the first cooling module 1 protrude through the imaginary boundary surface of the housing interior spanned by the opening 47, i.e. in particular by the housing flange surface 51, into the interior of the housing 41.

[0081] In the assembled position of the first cooling module 1, the longitudinal profile of the catching ribs 3 follows the shape of the gears 45, for which circular indentations are formed in the catching ribs 3. The number and shape of these circular indentations are selected such that, on the one hand, the gears for the various gear ratios with which the housing 41 can be equipped are not hindered in their intended movement by the catching ribs 3, and on the other hand, the catching ribs 3 follow as closely as possible, at least partially, the area swept by the gears in order to be able to easily absorb oil thrown off by the gears. The spacing of the catching ribs is selected, with particular consideration given to the viscosity of the oil, such that the gears are not noticeably slowed down in their intended movement by oil located between the catching ribs and the gears.

[0082] A three-part design of the catching ribs 3 in the manner shown has proven to be advantageous. Fig. 1c, other embodiments of the retaining ribs 3 are also encompassed by the invention. For example, the retaining ribs 3 can be provided to project laterally into the area of ​​the housing interior to the left of the opening 47, thereby better covering, in particular, the gear on the input shaft 42.

[0083] In a further embodiment, the cooling fins are unevenly formed and partially extend into areas next to gear 45.

[0084] In assembled position, as in Fig. As illustrated in Figure 4a, the first cooling module 1 collects oil flung away by the gears 45 via its collecting ribs 3. The collecting ribs 3 are aligned such that they collect as much oil as possible in the collecting areas 14 formed by them and the side surfaces of the collecting ribs 3 are covered with oil as completely as possible. This oil transfers heat to the collecting ribs 3 while flowing back into the oil sump of the gearbox 40. The heat absorbed by the collecting ribs 3 is transported via the collecting ribs 3 to the module plate 2, where it is transferred to a coolant flowing in the coolant groove 9. A cooling circuit that continuously exchanges the coolant is connected via the connecting couplings 55. Groove bottom elevations in the coolant groove 9 cause turbulent flow of the coolant, whereby particularly good heat dissipation by the coolant is achieved even at slow flow speeds.

[0085] With bath lubrication in the gearbox, rotation of the gearing and friction generate an oil flow that is directed through the collecting areas 14. Heat is transferred to the collecting ribs 3.

[0086] With splash lubrication in the gearbox, the rotation of the geared parts causes oil to be thrown into the collecting areas 14. With forced circulation lubrication, oil can be directed into the collecting areas 14. The lubrication used depends on the gearbox design, i.e., the orientation of the gearbox housing relative to the direction of gravity in the assembled state. The cooling module can be used advantageously in all designs.

[0087] In this way, the cooling of the transmission 40 can be advantageously improved by the subsequent installation of a first cooling module 1.

[0088] Fig. Figure 4b shows the use of another embodiment of a passive cooling module. A passive cooling module 60 is tightly mounted on the housing flange surface 51 of the gearbox 40.

[0089] The passive cooling module 60 has parallel catching ribs 3 on its underside, which, as in Fig. 4a protrude into the interior of the gear housing 41.

[0090] On its upper side, the passive cooling module 60 has parallel cooling fins 62. The cooling fins 62 are advantageously designed to be congruent with one another.

[0091] Advantageously, the passive cooling module 60 can be designed in two parts, consisting of an upper part with cooling fins 62 and a lower part with catching fins 3. Such a design shows Fig. 6, on the left in side view and on the right in cross-section. The upper and lower parts are connected to each other at a contact surface 110. In further embodiments, the contact surface is additionally coated with a thermally conductive paste.

[0092] In further embodiments, the passive cooling module 60 is made in one piece, i.e. in particular from a single casting.

[0093] When the gearbox 40 is used as intended, the catching ribs 3 absorb oil thrown off the gears 45, thereby transporting heat from the gearbox 40 to the catching ribs 3. The latter conduct the heat via the body of the passive cooling module 60 to the cooling ribs 62, which ultimately dissipate the heat to the environment, for example, air.

[0094] The advantage of this embodiment is that a coolant circuit can be dispensed with and the cooling of the transmission 40 can still be improved.

[0095] Fig. 4c shows another example of use of a cooling module according to the invention. Instead of the housing cover 49 in Fig. 4a, a first module cover 70 is placed on the first cooling module 1, which has parallel cooling fins 62 on its upper side.

[0096] Such a cooling module with module cover shows Fig. 7 in cross-section. The contact surface 111, which connects the first module cover 70 to the first cooling module 1, has sealing means (not shown) for sealing the coolant groove 9 to the outside.

[0097] The intended use of the first cooling module 1 is as follows: Fig. 4a. The cooling performance is further enhanced by the cooling fins 62 provided on the module cover, through which heat can be dissipated to the environment. Safety is also increased because emergency cooling can be achieved via the cooling fins 62 even in the event of a coolant circuit failure.

[0098] Fig. 4d shows another example of the use of a cooling module on a bevel gear.

[0099] In contrast to Fig. 4a, an oil module 80 is placed on the housing flange surface 51, followed by a coolant module 82, and a second module cover 84. This placement creates a tight connection. The oil module 80, coolant module 82, and second module cover 84 each have corresponding boreholes 58 through which screws 52 can be passed to connect the modules 80, 82 and the cover 84 to the housing 41. The screws engage in threaded holes 57. Each screw 52 advantageously connects all modules 80, 82 and the cover 84 to the housing 41 equally.

[0100] The oil module 80 differs from the first cooling module 1 according to Fig. 1a and Fig. 4a in that instead of the connection couplings 55, blind plugs 86 are provided which close the connection openings 10, and that in addition, on the underside of the module plate 2 holes are provided which open into the groove ends 11 via the closed connection openings 10.

[0101] These additional holes fit onto connecting pieces 88 provided on the housing flange surface 51 when the oil module 80 is mounted. These connecting pieces 88 are each designed as a rolled-up tube in the cover flange. Thus, oil circulated through piping by a pump inside the housing 41 can be conducted through the oil module 80, particularly through its coolant groove. This allows heat from the oil to be transferred to the cooling device in a particularly advantageous manner, especially when the oil level in the gear housing 41 is low or when the output-side gear 45 rotates slowly due to a large overall transmission ratio.

[0102] The piping is formed by pipes running inside and outside the housing, through which oil is pumped, for example as a pressure circulation lubrication system, in particular for gear or bearing lubrication.

[0103] The pump can be provided as a shaft pump or as an electrically driven pump, which is preferably attached to the outside of the gear housing 41.

[0104] The piping and / or pump also have oil filters.

[0105] In a further embodiment, the piping comprises a nozzle through which oil is directed or sprayed onto the catching ribs 3 by the pressure circulation lubrication.

[0106] In a further embodiment, the connecting pieces 88 are designed as boreholes which have additional sealing means.

[0107] The coolant module 80 in Fig. 4d differs from the first cooling module 1 according to Fig. 1a and Fig. 4a in that the catching ribs 3 are not provided. After installation on the oil module 80, a coolant circuit can be connected via connecting couplings, through which heat can be removed from the oil module 80.

[0108] The second module cover 84 in Fig. 4d has cooling fingers 89 on its upper side, arranged in longitudinal and transverse rows. Heat can be dissipated from the coolant module 82 to the environment, particularly to the air, via the cooling fingers 89.

[0109] The bevel gear in Fig. 4d has an input shaft on one end face, the input side 90, on which a fan 91 is mounted. The air moved by the fan 91 is partially directed by an air guide device 92 onto the cooling fingers 89 of the second module cover 84, thereby achieving a further increase in cooling performance on the gearbox.

[0110] In a further embodiment, no fan is provided. Compared to the first module cover 70 of Fig. 6, the cooling fingers 89 allow air to flow convectively in more than one direction. Thus, depending on the orientation of the gearbox in space—the design—improved heat dissipation can be achieved, even without a fan.

[0111] Fig. 5a shows the device according to Fig. 4d in assembled form.

[0112] Fig. 5b shows a longitudinal section through a section of the Fig. 5a. The longitudinal profile of the catching ribs 3, with its circular curvature 4, follows the shape of the gear 45. The circular curvatures 5, 6 are designed such that a single longitudinal profile provides sufficient space for various gears 46, while still allowing for easy absorption of flung oil. A distance of approximately 5 mm between the catching ribs and the gears has proven particularly advantageous for absorbing the oil; however, smaller clearances are also conceivable within the manufacturing tolerances.

[0113] Oil module 80, coolant module 82, and second module cover 84 form an oil channel 100 and a coolant channel 102. Oil is pumped through pipes 95 via the pressure lubrication pump through oil channel 100. Coolant is pumped from a cooling circuit through coolant channel 102 via connecting couplings 55. A fan 91 directs air over the cooling fingers 89 via an air guide device 92.

[0114] The device according to Fig. 4d, Fig. 5a and Fig. 5b thus forms a plurality of paths by which heat can be transported from the transmission to the environment: from gear wheels 45, 46 via thrown-away oil on catching ribs 3 and further to the oil module 80; from the oil sump via pipes 95 to the oil module 80; from the oil module 80 to the coolant module 82; from the coolant module 82 via the coolant in the coolant channel 102 to the coolant circuit; from the coolant module 82 via the second module cover 84 to the ambient air.

[0115] This allows for particularly high cooling performance for the gearbox.

[0116] In a further embodiment, a first module cover 70 is provided instead of the second module cover 84.

[0117] In a further embodiment, the housing cover 49 is provided instead of the second module cover 84. In this case, at least the air guiding device 92 can be omitted.

[0118] The Fig. 4a to 4d show exemplary embodiments of cooling devices which can be particularly advantageously assembled from a modular system.

[0119] In particular, the opening 47 is designed as an interface for connecting to the various cooling modules or modules or covers.

[0120] This allows for a wide range of additional cooling performance levels using a small number of components. By combining the various individual features of the described embodiments, further embodiments are created that are also encompassed by the invention.

[0121] The following properties are advantageous: i) A plurality of gears have an identically designed opening 47. ii) The base plates of the modules with meandering grooves are identical in design. iii) The base plates of the modules without groove or cover, including in particular the housing cover of the opening, are designed identically. iv) All base plates have the same hole pattern so that they can be connected to each other and to the gearbox housing. v) All base plates have matching sealants. vi) The surfaces of the base plates each form an interface, including at least a drilling pattern, sealing recesses, and centering elements. The interfaces are designed to match each other, allowing the various modules and covers to be combined effectively.

[0122] The design of the interface thus advantageously enables a multitude of possible combinations.

[0123] In particular, the housing cover, which is mounted on the opening of a gearbox without a cooling device according to the invention, can be used to cover the coolant groove in a module additionally used to improve cooling.

[0124] The described modular system for cooling devices on gearboxes has the particularly advantageous effect of allowing a gearbox to be easily and cost-effectively retrofitted with a cooling device, whereby the additional cooling capacity can be increased in stages and thus adapted particularly suitably. List of reference symbols 1 first cooling module 2 module plate 3 catching ribs 4, 5, 6 circular vault 7, 8 Circle intersection 9 Coolant groove 10 Connection opening 11 groove end 12 Groove bottom elevation 14 Collection area 17 Passage 19 second cooling module 20 catching fingers 21 Reception area 22, 23 Circle intersection 29 third cooling module 30 module base 31 Module top 32 hollow rib 33 full rib 34 Coolant channel 35 passage 36 connection opening 40 gearboxes 41 Gearbox housing 42 driving shaft 43 Cover 45, 46 gear 47 Opening 49 Housing cover 51 Housing flange surface 52 screw 53 Module flange area 55 connection coupling 57 threaded hole 60 passive cooling module 62 cooling fins 70 first module cover 80 oil module 82 Coolant module 84 second module cover 86 blind plugs 88 connecting piece 89 cold fingers 90 Input side 91 fans 92 Air guiding device 95 pipe 100 oil channel 102 Coolant channel 110, 111 contact surface

Claims

[1] Cooling module (29) for a gearbox (40), wherein the cooling module (29) comprises a cast part (30) in which a space (34) for flowing coolant, in particular air or water, is provided, wherein cooling fins (32) and / or cooling fingers directed into the interior of the gearbox are attached to the casting (30), wherein the outer edge of the cooling fins (32) and / or the ends of the cooling fingers follow the shape of a rotating part (45) or several rotating parts (45, 46) of the gear (40), wherein the cooling module (29) can close an opening (47) in the gear housing (41) of the gear (40), the edge of which opening defines a minimum area through which the cooling fins (32) and / or cooling fingers protrude into the interior of the gear (40), so that two spatial areas are present, namely the first spatial area (34) for a flowing coolant and a second spatial area located inside the gearbox for the contact of the cooling fins (32) or cooling fingers with lubricating oil flowing in the gearbox housing (41), characterized by , that the cooling fins (32) and / or cooling fingers are hollow to accommodate a coolant. [2] Cooling module (29) according to claim 1, characterized by that the cooling fins (32) and / or cooling fingers are formed integrally with the casting (30). [3] Modular system for gearbox cooling devices, comprising modules (1, 19, 29, 60, 80, 82) and covers (49, 70, 84), wherein the kit comprises at least one cooling module (29) according to one of the preceding claims 1 to 2, wherein the modules (1, 19, 29, 60, 80, 82) and covers (49, 70, 84) can each be placed on a housing interface of a gear housing (41) for closing an opening (47), wherein the modules (1, 19, 29, 60, 80, 82) and cover (49, 70, 84) have an internal connection interface which fits onto the housing interface of the opening (47) of the gear housing (41), wherein the modules (1, 19, 80, 82) have an external connection interface, wherein the external connection interface and the housing interface are of the same design. [4] Modular system for transmission cooling devices according to claim 3, characterized by , that the outer and inner connection interface each comprises at least one drilling pattern and / or sealing means and / or formations for sealing and / or centering means, wherein the connection of the interfaces is effected by means of screws and / or clamping elements and / or locking connecting elements and / or the connection of all modules and covers selected for a transmission cooling device is effected with the same set of fastening means (52). [5] Modular system for transmission cooling devices according to at least one of the preceding claims 3 to 4, characterized by , that the gear cooling devices can be used in a series of gearboxes which differ in terms of their respective gear ratios due to the selection of the gears provided, and / or that at least one cover (70, 84) has cooling fins and / or cooling fingers (89) on its outwardly directed side. [6] Modular system for transmission cooling devices according to at least one of the preceding claims 3 to 5, characterized bythat the kit comprises an air guiding device (92) with which air from a fan (91) can be guided over the transmission cooling device.

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