Oil filter for a liquid cooling system with a predetermined breaking point and a liquid cooling system having this point

Abstract

In various embodiments, an oil filter (1) is provided for a liquid cooling system, wherein the oil filter (1) has a housing which has a predetermined breaking point (5). Furthermore, a cooling circuit system is provided, in particular for an electric vehicle, which includes the oil filter (1).

Description

[0001] The present invention relates to an oil filter for a liquid cooling system with a predetermined breaking point and a cooling system comprising this.

[0002] Electric vehicles use synchronous or asynchronous motors as drive motors instead of combustion engines. The energy required for this is supplied by traction batteries, which, due to their size and weight, are usually located in the vehicle floor between the axles. Since the electric motors currently installed in electric vehicles are slowly approaching the power range of one megawatt, an efficient cooling concept is essential for both the electric motor and the traction battery that powers it.

[0003] To maintain a traction battery within its optimal temperature range, regardless of the driving performance and even at high ambient temperatures, thus enabling greater driving ranges due to more efficient battery operation, liquid cooling systems have proven effective. This fundamental principle is well-established in the art. Various implementations exist, ranging from dissipating waste heat via liquid-filled cooling elements attached to the outside of the battery cell modules to the novel approach of immersion cooling, where the battery cells and their electrical connections are directly surrounded by a coolant. This method allows for particularly effective dissipation of the released waste heat.

[0004] Regardless of the specific implementation of liquid cooling, a relatively large quantity (approximately 50 liters or more) of low-viscosity oil with very low conductivity (also known as thermal insulation fluid) circulates in a liquid cooling system in an electric vehicle. The oil circuit is extensive within the vehicle and typically includes an oil filter to keep the cooling oil circulating in the cooling system clean. The oil filter must be replaced during an oil change. Furthermore, removing the oil filter may be necessary during vehicle repairs, for example, when removing the front axle to disconnect the electrical wiring behind it. In such cases, the oil filter is also replaced afterward.

[0005] To avoid having to drain all the oil, a shut-off device is usually provided in either the inlet and / or outlet of the oil filter to isolate it from the cooling circuit. However, even after closing at least one of these shut-off devices, residual oil may still remain in the lines connected to the oil filter, sometimes even under pressure. When disconnecting couplings from the oil filter, oil can flow out uncontrollably, posing a risk of contamination. This highly penetrating, low-viscosity oil can spread throughout the vehicle, onto the tools used, and potentially even in the workshop. This results in contamination, compromises workplace safety, and necessitates time-consuming and costly cleanup.

[0006] In this context, German patent application DE 102019210057 A discloses an accumulator with a housing in which accumulator cells are accommodated, and wherein the internal volume is at least partially filled with a liquid fluid (6) during operation. A plug is provided on the housing for draining the fluid from the internal volume, which is intended to simplify maintenance of the accumulator.

[0007] An oil-cooled battery with a drain valve is also known from printed document DE 102020205930 A1.

[0008] Publication CN 206864570 U discloses a battery protection device comprising a battery box and a drain valve.

[0009] In light of the aforementioned prior art, the object of the present invention can be seen as providing an oil filter whose replacement can at least partially avoid the problems described above.

[0010] This problem is solved by means of the subject matter of the independent claims. Further preferred embodiments are found in the dependent claims.

[0011] The present invention is based on the finding that the aforementioned problems can be at least partially solved by providing a predetermined breaking point on the oil filter housing. By selectively opening the oil filter housing, preferably on its underside, the cooling oil can flow out of the cooling circuit in a controlled manner. An oil collection device can be installed directly below the extraction point.

[0012] The present invention further takes advantage of the fact that, unlike, for example, a drain plug, the predetermined breaking point according to the invention does not entail any additional costs for the oil filter, since it is disposed of after removal anyway.

[0013] According to the invention, an oil filter for a liquid cooling system is provided, wherein the oil filter has a housing with a predetermined breaking point. The predetermined breaking point can be implemented in various ways, which are described in more detail below. It is important that the predetermined breaking point is designed to allow the oil to drain from the oil filter. The predetermined breaking point can be opened with a suitable tool, e.g., by punching it with a center punch. After the oil contained in the filter and its connecting pipes has been drained, the filter can be safely removed.

[0014] According to further embodiments of the oil filter, the predetermined breaking point can have a thinner wall than the surrounding housing part. This allows the filter housing to be easily opened via the predetermined breaking point.

[0015] According to further embodiments of the oil filter, the predetermined breaking point can have a contour with a wall thickness that is less than the wall thickness of the housing part surrounding the contour. This allows a defined opening area to be created when the oil filter housing is opened.

[0016] According to further embodiments of the oil filter, an opening element can be arranged at the predetermined breaking point. This opening element can help to apply force to the predetermined point in order to detach it from the surrounding housing or at least break it open.

[0017] The opening element may have a projection extending outwards from the housing. This projection may be a pin, over which a torque can be applied to the predetermined breaking point using pliers, causing it to break open and allowing the oil to drain in a controlled manner.

[0018] The opening element can further have an opening tab, which can represent a particularly flat form of the opening element. The opening tab can allow a moment to be applied to the predetermined breaking point, causing it to break in a predetermined area and thus opening the housing (e.g. similar to a beverage can with an opening tab).

[0019] According to further embodiments of the oil filter, the predetermined breaking point can be located in an area between two fastenings of the housing to its surroundings.

[0020] According to further embodiments of the oil filter, the predetermined breaking point can be located on the underside of the filter. This minimizes the amount of oil remaining in the oil filter after the predetermined breaking point is opened, as the oil will accumulate in the lower part of the oil filter due to gravity.

[0021] According to the invention, a cooling circuit system is further provided, in particular for an electric vehicle, comprising an oil filter according to one of the embodiments described above. The cooling circuit system may otherwise have a structure known from the prior art and thus, in particular, further components such as a pump, a heat exchanger, and a piping system.

[0022] According to further embodiments of the cooling circuit system, a shut-off valve can be installed upstream of a first connection, such as the inlet connection of the oil filter. Furthermore, a second connection, such as the outlet connection of the filter, can be connected to a flexible hose. The flexible hose can be made of elastomer and can assist in the installation of the oil filter. The flexible hose allows the filter to be moved in at least one direction, such as axially, thus simplifying the removal of quick-release couplings from the filter.

[0023] The features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0024] Further advantages and embodiments of the invention will become apparent from the following description of exemplary embodiments and the accompanying drawings. Fig. Figure 1 shows an embodiment of the oil filter according to the invention. Fig. 2A and Fig. Figure 2B shows an exemplary embodiment of the predetermined breaking point on an oil filter according to the invention.

[0025] In Fig. Figure 1 illustrates an embodiment of the oil filter 1 according to the invention. The oil filter 1 is part of a liquid cooling system, which includes an arrangement of lines 4 and other parts that are not relevant from the perspective of the invention and are therefore not shown. Fig. 1 are not shown. A shut-off valve 2 is located at one connection of the oil filter 1, e.g. in the inlet path. The second connection, e.g. the outlet path, is connected to the piping system 4 of the liquid cooling system by means of a flexible hose 3.

[0026] The oil filter 1 according to the invention is characterized by having a predetermined breaking point 5. In the example shown, this is arranged on the underside of the oil filter 1. In addition, the predetermined breaking point 5 is arranged between the fastenings 6 of the oil filter 6 on its surroundings (here, for example, the vehicle body).

[0027] In the Fig. 2A and Fig. 2B and Fig. Figure 2B illustrates an exemplary embodiment of the predetermined breaking point 5 on an oil filter 1 according to the invention. The predetermined breaking point is designed in the form of a plunger, which has a base 51 and a projection 52 arranged thereon. The base 51 can have a contour along which the housing is designed with a reduced material thickness to simplify the opening of the predetermined breaking point 5. The projection 52 can have the form of a pin. The base 51 of the predetermined breaking point 5 defines an opening surface through which the cooling oil 7 flows out after the predetermined breaking point 5 is ruptured.

[0028] As in Fig. As shown in Figure 2B, a torque D (e.g., using pliers) can be applied to the base 51 via the projection 52 to detach it from the housing of the oil filter 1. The oil 7 that then flows out in a controlled manner can be collected by means of an oil collection device, which can be positioned or attached directly below the extraction point. QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] DE 102019210057 A

[0006] DE 102020205930 A1

[0007] CN 206864570 U

[0008]

Claims

[1] Oil filter (1) for a liquid cooling system, wherein the oil filter (1) has a housing which has a predetermined breaking point (5). [2] Oil filter (1) according to claim 1, wherein the predetermined breaking point (5) has a lesser wall thickness than a housing part surrounding it. [3] Oil filter (1) according to claim 2, wherein the predetermined breaking point (5) has a contour which has a lesser wall thickness than the housing part surrounding it. [4] Oil filter (1) according to one of claims 1 to 3, wherein an opening element (52) is arranged at the predetermined breaking point (5). [5] Oil filter (1) according to claim 4, wherein the opening element (52) is a projection extending outwards from the housing. [6] Oil filter (1) according to claim 4, wherein the opening element is an opening tab attached to the predetermined breaking point (5). [7] Oil filter (1) according to any one of claims 1 to 6, wherein the predetermined breaking point (5) is arranged in an area between two fastenings (6) of the housing to its surroundings. [8] Oil filter according to any one of claims 1 to 7, wherein the predetermined breaking point is arranged on an underside of the filter. [9] Liquid cooling system, in particular for an electric vehicle, comprising: an oil filter (1) according to any one of the preceding claims. [10] Cooling circuit according to claim 9, wherein a shut-off valve (2) is connected upstream of a first connection of the oil filter (1) and a second connection of the oil filter (1) is connected to a flexible hose (3).

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