Patent Application
20250116214
This application claims the benefit of and right of priority under 35 U.S.C. § 119 to German Patent Application no. 10 2023 209 863.6, filed on 10 Oct. 2023, the contents of which are incorporated herein by reference in its entirety.
The invention relates to a device for producing an oil pan, the device comprising a pan underside with a pan bottom and an all-around sidewall which is arranged on the pan bottom to form a leakproof hollow space with the pan bottom, wherein a partition wall is provided in the hollow space that divides the hollow space into a suction space for forming a suction opening and an outflow space for forming an outflow opening for the oil to flow out along an outflow direction, and wherein fluid openings are provided in the partition wall for the oil to flow through from the suction space into the outflow space. In addition, the invention relates to an oil pan arrangement.
Owing to high loads and the demands for long useful life in utility vehicles (50,000 hours), oil pans made of plastic are virtually never used in the commercial vehicle segment. A separate aluminum oil pan is normally developed for each commercial vehicle transmission, which can then only be used for the respective product.
Owing to the high loads in combination with the strict demand for long useful life, it is inevitable that wear and contamination will take place in the drive aggregate.
Accordingly, in powershiftable automatic transmissions and other automatic transmissions, specially designed suction filters and/or pressure filters are used in order to protect the sensitive hydraulic valve systems against dirt and to ensure their proper functioning. These filters are then normally designed and optimized for the specific product and for the fitting space of the oil pan available.
In many cases the filter elements are even integrated in the oil pan.
Such oil pans are known in numerous versions from the prior art. The oil pans serve in particular as reservoir containers of oil, which is required for the lubrication of a drive aggregate. In particular, plastic oil pans are used in the automotive sector, for example, as oil pans in motor vehicles.
From DE 19914607 C2, a plastic oil pan for vehicle motors and transmissions is known, in particular for automatic transmissions, which comprises a pan bottom, an all-round sidewall, an all-round raised portion arranged on the inside of the pan bottom, and means for withstanding external forces, which means are arranged at least on the outside of the pan bottom.
From DE 19735445 A1, an oil pan made of plastic or metal for motors or transmissions or automatic transmissions with integrated suction and/or pressure oil filtration is known, in which the oil filter is arranged in the oil pan.
DE 102008053279 A1 discloses an oil pan made of metal for motors or transmissions, with an oil filter medium arranged in the oil pan, wherein part of the oil pan is the bottom of an oil filter housing and a plastic half-shell forms a cover of the oil filter housing and the oil filter medium is arranged between the oil pan and the plastic half-shell, wherein at its edge the oil pan has metallic rivets and the plastic half-shell has at its edge holes by virtue of which the plastic half-shell is fixed onto the metallic oil pan.
It is thus a purpose of the present invention to indicate an improved device for producing an oil pan, and an oil pan arrangement.
The objective is achieved by a device for producing an oil pan and an oil pan arrangement as disclosed herein.
Additional embodiments and advantageous features will be apparent from the present disclosure, which features can be combined appropriately with one another in order to achieve further advantages.
The objective is achieved by a device for forming an oil pan, the device comprising an oil pan underside with an oil pan bottom and an all-round sidewall which is arranged on the oil pan bottom, for forming a leakproof hollow space with the oil pan bottom, wherein a partition wall is provided in the hollow space that divides the hollow space into a suction space for forming a suction opening and an outflow space for forming an outflow opening for the oil to flow out along an outflow direction, wherein fluid openings are provided in the partition wall for the oil to flow through from the suction space into the outflow space,
wherein a filter element and/or a sieve element is provided, which is integrated in the outflow space for filtering the oil flowing through the outflow space,
and wherein a supporting grid is provided, which is arranged in the outflow direction of the oil above the filter element and/or sieve element, wherein the supporting grid is attached to an inner side of the sidewall for fixing the filter element and/or sieve element between the supporting grid and the oil pan bottom when the oil is flowing out in the outflow direction,
and wherein fixing means are provided on an outside of the sidewall for fixing the oil pan underside to a correspondingly designed wall as the upper side of the oil pan to form the oil pan.
In particular, the length and width of the filter element and/or sieve element are such as to span across the outflow space completely.
In particular, the fluid openings in the partition wall are arranged under the filter element and/or sieve element so that the oil from the suction space flows under the filter element and/or sieve element and from there through the filter element and/or sieve element. During the outflow the filter element and/or sieve element is held against the supporting grid, so that the fluid openings can be arranged slightly under the filter element and/or sieve element in order to ensure that the oil will flow through during operation. It is also possible for the supporting grid to be designed in such manner that the through-flow direction can be reversed, or so that both through-flow directions are possible.
The partition wall can have any desired shape, for example as a rectangle or even an oblique wall, for forming the suction space in triangular form. Moreover, the supporting grid can be in the form of a single-layer stainless steel grid.
The wall is in particular the wall of a housing which is connected to an oil-draining line (suction duct) for conveying the oil through the oil pump to the components or parts that need it.
Particularly in traction machines, to avoid extreme temperatures, an electrically powered oil pump is used. In the electrical drive the pump has the function of lubricating and cooling the traction machines and bearings and gearteeth. However, other functions also are conceivable.
Other than in the oil pumps used in utility vehicles until now, this oil pump is not driven by the traction machine (with a virtually limitless torque), but rather, by a relatively small electric motor. According to the invention, it was recognized that in this way the pump can deliver a volume flow for lubrication and cooling which is fully independent of the rest of the system. Thus, “after-running” of the pump is also possible. That makes for very great flexibility and offers the possibility of volume flow regulation “according to need.” Basically, such an electric oil pump can be used in any application, i.e., as well in conventional transmissions as in other applications. In such cases a suction filter is always needed in order to protect the pump.
By virtue of the invention, now both reliable operation is enabled and a standstill (functional breakdown) of the pump in a very small fitting space is prevented, since dirt particles are filtered out and since all dirt particles larger than a certain size are held back.
Thanks to the design of the device according to the invention as an open oil pan, it can be made as “thin” as possible (in terms of its height), so as not to extend unnecessarily downward (toward the road). During operation this may be the lowest point, which as regards the suction, is an advantage.
According to the invention, the “upper shell of the oil pan” is formed in each case by the corresponding counter-housing (wall) on which the oil pan is mounted. In that way the device with the filter or sieve element can be used as an oil pan in vehicles of the most varied types.
By virtue of the device according to the invention the orientation of attached components such as oil pumps and heat exchangers, which always have to allow for their function and for the fitting space available in the vehicle, is taken into account. Thanks to the device according to the invention the oil pump can be arranged universally in any vehicle, and no longer is any special attention to its orientation needed.
By using the housing as the upper side of the oil pan and also by fixing the filter element and/or the sieve element by means of the supporting grid, no supporting domes or webs or suchlike are required. In that way the supply to the suction duct of the oil pump can be designed completely flexibly in the area of the supporting grid.
Furthermore, by virtue of this design the oil pan can be made as thin as possible in terms of its height.
In addition, flexible installation in any vehicle is enabled. Thus, to form an oil pan the device could even be fitted “upside-down” or vertically.
The suction opening defines the point in the aggregate as a whole where suction takes place. Thanks to the device according to the invention this can now be located at the volumetric center in a simple manner, so as to ensure that sufficient oil is present at all times.
In most cases, in relation to the oil pan the volumetric center is in the lower middle part of the aggregate. Due to the integration of the suction opening in the oil pan this also becomes the “path” from the suction point to the suction duct of the oil pump. Thus, the oil pan functions as a kind of hydraulic channel. By virtue of the design according to the invention as an open oil pan in which the counter-housing forms the upper side of the oil pan, the oil pan can be rotated as desired, all the better to extend from the suction point (suction opening) to the suction duct of the pump in the optimum way. This is particularly advantageous in the case of electrical drives, into which traction machines are built, since thereby a simple duct path from the suction point (suction opening) to the suction duct (outflow opening) of the electric oil pump is realized. By fitting the oil pan underside from outside onto any aggregate, during the useful life of the vehicle the filter element or the oil pan underside can be replaced. In that way all the dirt is always removed automatically form the oil system.
Moreover, the oil pan underside can even be unscrewed in order to clean the filter or sieve element, the flow direction being reversed so that all the dirt is flushed out of the filter or sieve element through the suction opening. Thus, the filter or sieve element can even be re-used. However, it is also possible if requirements are particularly strict to replace the filter or sieve element by a finer grid or tissue.
By using a supporting grid, the filter element and/or sieve element can be fixed in a uniform manner. Thanks to the homogeneous support by the supporting grid the tissue of the filter element and/or sieve element is less encumbered at particular points. By not using housing domes for fixing the filter element and/or sieve element, any negative effect of such housing domes on the flow can be prevented.
In particular, the device according to the invention is notable in that it can be produced more simply, since for example housing domes have to be cast and this is costly.
Furthermore, thanks to such a design of the device the oil pan acts as a channel through the suction space and the outflow space, with a small height and in which the oil is filtered.
As a further feature, the supporting grid can be fixed with interlock to the inside of the sidewall. This enables simple fixing.
In particular, the supporting grid is welded to the inside of the sidewall.
In particular, an all-round weld can be made, so that even if the suction pressure is high the fixing of the supporting grid and hence of the filter and/or sieve element as well is ensured.
As a further feature, the filter and/or sieve element spans across the outflow space completely, so that when flowing out all of the oil passes through the filter and/or sieve element. This means that the length and width of the filter and/or sieve element are matched to the length and width of the outflow space. In that way a large filtration area is created.
By virtue of the flow direction from the suction opening in the oil pan to the transfer point on the wall of the housing of the aggregate concerned, in combination with the relatively large filtration area, it is ensured that a low counter-pressure is produced. Likewise, the flow direction ensures that all particles larger than the specified mesh width of the filter element and/or sieve element are always filtered out by the filter and/or sieve element.
In a further development, the fixing means on the outside of the sidewall comprise holding elements that project in an axial direction, and sleeves which are inserted into the holding elements in a vertical direction so that by virtue of the sleeves the oil pan underside can be fixed to the wall by means of fastening elements. This means that coated metallic sleeves can be inserted or overmolded into the holding elements, which ensure simpler fixing to the aggregate concerned and the compression of the inlaid molded seal during the useful life of the vehicle and while it is in use.
In particular, the fixing means can consist of the projecting holding elements and the sleeves.
Thanks to the sleeves simple screwing-on, is possible without stressing the oil pan with pressure.
In particular, the holding elements and the oil pan underside, the sidewall, and the partition wall can be made integrally as one piece, for example as an injection-molded plastic component. This enables simple production.
In a further development, the sidewall and also the partition wall have a groove and a seal in the direction toward the wall, which seal is fitted into the groove to form a seal. In that way the oil pan underside, is arranged and sealed against the wall, which in this case is the upper side of the oil pan.
In a further feature, honeycomb-like ribs are arranged on the outside of the oil pan bottom. This enables the oil pan to be used in any driving direction, for example without impact by stones resulting in any damage to the oil pan. Thus, in a bus, for example, the oil pan is arranged behind the axle in the driving direction, and in a truck, it is arranged ahead of the axle in the driving direction. Moreover, in that way the oil pan can be arranged “transversely” relative to the driving direction.
In another design feature, the supporting grid can be in the form of a single-layer stainless steel grid. The oil pan can be taken off and, when necessary, the filter element and/or the sieve element can be removed easily or, if the components have been welded on, the flow direction can be reversed so as to remove all the dirt particles from the filter and/or sieve element by flushing them out. The filter and/or sieve elements could then be re-used. However, it is also possible if the requirements are stricter to replace the filter and/or sieve element by a finer tissue.
In a further development, the supporting grid is molded around the filter element on both sides. Thus, a supporting grid is arranged on the upper side and on the lower side so that filtering in both directions is possible. In particular, this enables the flow direction to be reversed in a simple manner.
This is advantageous for cleaning the filter element. Alternatively, corresponding support ribs can be provided in the basic body of the oil pan, i.e., in the outflow space which is then the suction space.
Furthermore, the set objective is achieved by an oil pan arrangement for producing an oil pan in particular in accordance with the above-described device, which comprises an oil pan underside with an oil pan bottom and an all-round sidewall arranged on the oil pan bottom for creating a leakproof hollow space with the oil pan bottom, wherein a partition wall is provided in the hollow space, which divides the hollow space into a suction space to form a suction opening and an outflow space to form an outflow opening for the oil to flow out along an outflow direction, wherein fluid openings are provided in the partition wall for the oil to flow through from the suction space into the outflow space, and wherein
a filter element and/or a sieve element is provided, which is integrated in the outflow space to filter the oil flowing through the outflow space,
and wherein a supporting grid is provided, which is arranged in the outflow direction of the oil above the filter element and/or the sieve element, wherein the supporting grid is attached to an inside of the sidewall for fixing the filter element and/or sieve element between the supporting grid and the oil pan bottom while the oil is flowing out in the outflow direction, and
wherein fastening means are provided on an outside of the sidewall,
and wherein a wall of a housing is provided as the upper side of the oil pan, onto which the oil pan underside is attached by means of the fastening means to form the oil pan and wherein the wall is fluidically connected to an oil drainage line.
In particular, “fluidic” means that the wall is connected with an oil drainage line (suction duct) for conveying the oil to the parts or components that need it.
In this context, the advantages of the device and also its design features can be transferred to the oil pan arrangement.
Furthermore, in a further development, the fastening means comprise holding elements on an outer side of the sidewall that project in an axial direction, as well as sleeves which are inserted in the holding elements in a vertical direction and fastening elements which are inserted through the sleeves, with corresponding receiving openings provided on the wall of the housing, wherein the fastening elements are fixed into the receiving openings to form the oil pan.
Further features and advantages of the present invention emerge from the following description, with reference to the attached figures which show, in a schematic manner:
This comprises an oil pan underside 2. The oil pan underside 2 has an oil pan bottom 3 (
In addition, a partition wall 5 is provided, which divides the hollow space into a suction space 6 for forming a suction opening. From there the oil is drawn in or flows in. This suction opening defines the point in the aggregate as a whole where suction takes place. That point should if possible be at the volumetric center in order to ensure that enough oil is always present and that no air is drawn in.
Depending on the design of the partition wall 5, the suction space 6 can be triangular or even quadrangular or even round (
In most cases the volumetric center, relative to the oil pan, is in the lower middle of the aggregate such as a drive motor, transmission components with an electric oil pump, etc. In the case of electric drives, traction machines are installed, whereby the ducting from the suction point (suction opening) to the suction duct (outflow space 8) of the electric oil pump is relatively difficult to realize. By integrating the suction opening into the oil pan underside 2 this also adopts the role of a “path” from the suction point to the suction duct of the oil pump. In this case the oil pan underside 2 can be rotated as desired in order, in that way, to optimize the flow from the suction point to the suction duct of the pump.
Furthermore, the partition wall 5 divides the hollow space, forming an outflow space 8 for the oil to flow out along an outflow direction. In the partition wall 5 fluid openings 9 are provided for the oil to flow through from the suction space 6 into the outflow space 8, which in particular are arranged in the oil pan bottom 3 and form a duct therewith.
In addition, a filter element 10 is provided, which is integrated in the outflow space 8 in order to filter the oil flowing through from the suction space 6 via the fluid openings 9 into and through the outflow space 8. Preferably, the filter element 10 spans across the entire area (length, width) of the outflow space 8, whereby a large filtering area is created. The fluid openings 9 are preferably located in the partition wall 5 in such manner that during operation the oil flows under the filter element 10.
By virtue of the flow direction from the suction opening of the suction space 6 in the oil pan underside 2 to the transfer point in the housing of the aggregate concerned, in combination with the relatively large filtration area, it is ensured that a low counter-pressure is produced.
Likewise, the flow direction ensures that all particles larger than the specified mesh width of the filter element 10 are always filtered out by the filter element 10. In this version the particles remain in the space between the filter element 10 and the outflow space 8 or oil pan bottom.
Furthermore, a supporting grid 11 is provided, which is arranged opposite the oil pan bottom 3 (
The supporting grid 11 can be welded to the sidewall 4 all the way round. Adhesive bonding or screwing are also possible.
The supporting grid 11 is designed to withstand the maximum suction underpressure that occurs.
For example, the supporting grid 11 can be in the form of a single-layer stainless steel grid or a fabric filter element.
Thanks to the welding, the filter element 10 is not pulled into the suction duct by suction pressure, but instead remains between the supporting grid 11 and the oil pan bottom 3.
If the flow direction is to be reversed, the supporting grid 11 can be molded around the filter element 10 on both sides. Alternatively, appropriate supporting ribs can be provided in the basic body of the oil pan, i.e., in the outflow space 8, which is then the suction space.
In addition, on the outside of the sidewall 4 holding elements 12 that project in an axial direction A are provided. The holding elements 12 are for example in the form of flanges.
In the holding elements 12, coated metallic sleeves 13 are inserted or overmolded in a vertical direction V, for the insertion of screws. In that way fixing to any aggregate and compression of the inlaid shaped seal can be ensured over the useful life of the vehicle and when it is in use.
Thanks to the coated metallic sleeves 13, simple screwing is made possible without imposing any pressure on the oil pan.
In particular, the holding elements 12 and the oil pan underside 2, the sidewall 4, and the partition wall 5 can be made in one piece, for example in the form of an injection-molded plastic component. This enables simple production.
The axial direction A and the vertical direction V are perpendicular to one another.
By means of the screws (not shown) the entire oil pan underside 2 together with the filter element 10 and the supporting grid 11 can be screwed to the wall (not shown) of a housing of an aggregate, such as a motor. In that case the wall is connected to an appropriate oil-draining line (suction duct).
To form a seal between the oil pan underside 2 and the wall, both the sidewall 4 and the partition wall 5 have a groove into which a seal 14 is fitted. Once the oil pan underside 2 has been screwed onto the wall of the housing of the aggregate by way of the coated metallic sleeves 13 in the holding elements 12, a seal is formed so that the filtered, through-flowing oil does not leak out.
By screwing together, an oil pan is produced whose upper part is now formed by the housing of the corresponding aggregate itself.
This means that the upper shell of the oil pan is in each case formed by the corresponding counter-housing to which the oil pan underside 2 is fixed. In that way the oil pan with the filter element 10 can be used in the most diverse vehicles. Thanks to the device 1 according to the invention, the orientation of added components such as an oil pump and heat exchanger, which always have to allow for their function and the fitting space available in the vehicle, is automatically taken into account. Thus, by virtue of the device 1 according to the invention, the oil pumps can be arranged universally in any vehicle and special attention no longer needs to be paid to their orientation.
Since in this case the upper shell of the oil pan is formed by the housing, no supporting dome or webs for supporting are needed in the counter-housing. Thus, the supply to the suction duct of the oil pump can be designed with full flexibility in the area of the supporting grid 11 and also the filter element 10.
By virtue of its open configuration as a separate oil pan underside 2, and since the oil pan upper side is formed by the housing, the oil pan can be made as “thin (in terms of its height)” as possible, so that it does not extend unnecessarily “downward” (toward the road). Thus, it can be the lowest point of the vehicle, which is an advantage as regards the suction.
The filter element 10 is supported by the supporting grid 11 and does not therefore need any further supporting domes or the like on the wall of the housing of the aggregate. Thus, the oil pan could even be fitted upside-down or vertically provided that the guiding of ducts or pipes in the aggregate concerned ensures that oil is present at the suction opening.
Thanks to the fitting of the oil pan underside 2 from the outside to form an oil pan on the aggregate concerned, during the life of the vehicle the filter element 10 can be replaced. Moreover, all the dirt is always removed automatically from the system.
Furthermore, the oil pan underside 2 can even be unscrewed in order to clean the filter element 10, since the flow direction is changed so that all the dirt is flushed out of the filter element 10 through the suction opening of the suction space 6. In that way the filter element 10 can even be re-used. However, if the requirements are stricter the filter element 10 can be replaced by a finer tissue.
Thanks to the homogeneous support by the supporting grid 11, the fabric of the filter element 10 is less encumbered at particular points. By doing without housing domes for fixing the filter element 10, any negative effect of such housing domes on the flow can be avoided.
In particular, the oil pan underside 2 according to the invention is characterized by simpler production since the housing domes on the counter-housing, for example, have to be elaborately cast.
Such an oil pan can act as a duct via the suction space 6 and the outflow space 8, which duct has a low height and in which the oil is filtered.
By virtue of the flow direction from the suction opening in the oil pan to the transfer point in the wall of the housing of the aggregate concerned, in combination with the relatively large filtration area, it is ensured that a low counter-pressure will be produced.
Likewise, the flow direction ensures that all particles larger than the specified mesh width of the filter element 10 are always filtered out by the filter element 10.
The surface of the outside of the oil pan bottom 3 has honeycomb-like ribbing of which, here, some examples of honeycomb-like ribbing 7a, 7b, 7c, 7d are shown. This enables the use of the oil pan underside 2 in all driving directions without, for example, impact by stones resulting in damage to the oil pan bottom 3. Thus, for example, the oil pan in a bus is behind the axle as viewed in the driving direction, whereas in a truck it is in front of the axle as viewed in the driving direction. Thereby, the oil pan can also be positioned “transversely” relative to the driving direction.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 209 863.6 | Oct 2023 | DE | national |
