Oil suction device and motor vehicle

Abstract

Oil intake device for an oil circuit designed for cooling an electric drive motor of a motor vehicle, wherein the oil intake device is a housing with - an intake opening, - an interior space through which oil flows, and - a mounting interface for an oil supply line, and includes a sieve device with a sieve for filtering the oil flowing through the intake opening, wherein the sieve device is arranged inside the housing, wherein the sieve has a curved surface to increase the surface area.

Description

[0001] The invention relates to an oil intake device for an oil circuit designed for cooling an electric drive motor of a motor vehicle, wherein the oil intake device has a housing with an intake opening, an interior space through which oil can flow and a mounting interface for an oil guide line, and a filter device with a filter for filtering the oil flowing through the intake opening.

[0002] The electric drive unit, particularly the electric motor, of modern electric vehicles requires intensive cooling, which is often achieved by means of a dedicated oil circuit. To supply oil from a reservoir or oil tank for cooling, the oil circuit includes an oil intake device, specifically an oil intake manifold, located within the reservoir or tank. The oil intake manifold typically comprises either a metallic upper and lower section, which must be positively connected, or a plastic-based upper and lower section, which must be welded together, as well as a flat filter screen located within an interior formed by the connected or welded upper and lower sections.This type of oil intake manifold is usually very large to provide a sufficient filter surface area, complex to manufacture, and also limited in terms of positioning flexibility within the oil tank. The filter serves primarily to filter out unwanted particles such as abrasion particles.

[0003] Other designs have proposed extending the flat sieve over the appropriately sized intake opening or housing it in an attachment that fits onto the intake opening. Another suggestion was to provide a kind of sieve basket around the outside of the intake opening. This achieves a larger sieve area, but it also requires an additional component, which significantly increases the size of the oil intake device and makes it more difficult to achieve the desired effect of drawing oil even when the oil level in the collection tank is low.

[0004] From EP 3 278 857 A1, a sieve is known that is arranged in the interior of an injection pipe, wherein a reducing agent is injected into a fuel tank of a motor vehicle via an injection port. In internal combustion engines of conventional motor vehicles, a urea SRC system is used, which reduces the nitrogen oxides in the exhaust gases by means of a suitable reducing agent. The sieve comprises a cylindrical sieve body, wherein the front end section of the sieve is triangular or trapezoidal.

[0005] CN210714591U describes an oil nozzle and an oil delivery device, wherein the oil nozzle is arranged in an oil line and comprises an oil nozzle body and a filter element. The filter element is positioned parallel to the flow direction of the oil within the oil line and has a conical or cylindrical shape.

[0006] The invention is based on the objective of providing a small and handy, in particular easy-to-manufacture oil suction device for use in a motor vehicle, which can nevertheless provide a high sieve size.

[0007] To solve this problem, an oil intake device according to the invention of the type mentioned at the outset is provided, in which the sieve device is arranged in the interior of the housing, wherein the sieve has a curved surface to increase the surface area.

[0008] This design offers the advantage that, due to the curved surface of the sieve, it can be made significantly larger relative to the external dimensions of the oil intake device than would be possible with a sieve with a flat surface. Consequently, the curved surface of the sieve allows for a correspondingly smaller oil intake device, resulting in lower production costs. At the same time, the interior space of the oil intake device housing is optimally utilized without requiring an increase in housing size or additional components, or even a reduction in the size of the housing. Furthermore, the smaller size of the oil intake device also leads to a reduction in weight. Another advantage of this oil intake device is that the intake opening can be positioned more effectively at the lowest point of the housing, ensuring air-free oil extraction from the oil tank.By choosing the housing shape, which also defines the overall external shape, a more flexible design of the receiving housing is achieved, in which the oil intake device no longer necessarily has to be positioned in a specific location.

[0009] According to a preferred embodiment of the invention, the sieve can have a conical, frustoconical, and / or cylindrical shape. It is also conceivable that the sieve has a combination of two or three shapes. For example, one end of the sieve can be cylindrical, followed by a frustoconical sieve section. An advantage of these embodiments is that the curved surface of the sieve increases the surface area, allowing the sieve, and thus the entire oil intake device, to be made smaller without adversely affecting the filtering performance. Conical and cylindrical shapes offer an excellent way to provide large sieve areas while requiring minimal space within the housing.In addition, a sieve surface that is closed at least along the circumference can be provided in a simple way, which, if positioned appropriately, allows the interior to be divided into an intake area on the intake opening side and a transfer area on the interface side, thus ensuring that the oil is filtered overall.

[0010] According to a further development of the invention, the longitudinal axis of the sieve can be arranged transversely to the intake direction of the intake opening, and in particular perpendicular to it, within the housing. This offers the advantage that the oil encounters a large sieve surface, thereby ensuring thorough filtration of the oil. The longitudinal axis is understood here to be the axis of rotational symmetry of the corresponding cylindrical, conical, and / or truncated conical shape.

[0011] Furthermore, the surface of the sieve can have a corrugated shape. This design serves to further increase the surface area of ​​the sieve, particularly when a cylindrical, conical, or truncated conical shape is chosen, although other design variations are also possible. For example, the surface of the sieve can also have a serrated shape, which increases the surface area in a similar way to the corrugated shape.

[0012] Generally, it can be provided that the sieve has a sieve area of ​​500 to 1500 mm². 2 , for example 1000 or 1050 mm 2, is provided. The housing can be kept small, for example with a maximum dimension of three to six centimeters. The mesh size of the sieve can be, for example, in the range of 0.1 to 0.5 mm, or 0.25 to 0.35 mm. The thickness of the sieve can be, for example, 0.05 to 0.3 mm, or more specifically, 0.1 to 0.15 mm. The sieve can be made of steel and / or wire mesh.

[0013] Furthermore, the housing can have at least two housing sections, wherein a first housing section comprises the mounting interface for the oil supply line and a second housing section adjoining the first housing section comprises a receiving space for the filter device. In a preferred embodiment, both the first and second housing sections have a cylindrical cross-section and are, in particular, arranged concentrically against each other, forming a common cavity. With a rotationally symmetrical shape of the filter and a concentric arrangement, the filter can be positioned centrally or eccentrically.

[0014] Additionally, a third housing section, preferably also having a cylindrical cross-section, can be arranged adjacent to the second housing section, preferably transversely to the longitudinal axis of the cylindrical shape of the first and second housing sections. The third housing section can include the intake opening. It should be noted that in not all embodiments does the oil intake device in an oil tank need to be arranged such that the intake opening is directly connected to the oil tank. If the oil intake device is positioned higher in the oil tank, the intake opening can be "extended," so to speak, via a pipe or hose whose opposite opening is located at the bottom of the oil tank. Preferably, however, the third housing section itself can be designed such that, despite the planned arrangement of the first and second housing sections, the intake opening can be positioned as close as possible to the bottom of the oil tank.

[0015] The oil is drawn from the oil tank through the intake opening of the third housing section. It enters the second housing section and encounters the filter unit. Here, the oil is filtered, removing contaminant particles, and then flows into the discharge area within the second housing section. From there, the filtered oil flows through the first housing section into the oil supply line, which is attached to the first housing section via the mounting interface. This allows the oil to ultimately reach the electric drive motor via the oil circuit.

[0016] According to a further development of the invention, the transition from the first housing section to the second housing section can have a step, with a mounting element of the sieve assembly being placed on the step. To form the step that marks the transition from the first housing section to the second housing section, the inner diameter of the second housing section, which is particularly cylindrical, can be dimensioned larger than the inner diameter of the first housing section, which is particularly cylindrical at least in the area adjoining the second housing section. The inner diameter of the second housing section can be the same size as the diameter of the sieve assembly so that the latter can be inserted precisely into the second housing section. The sieve assembly can have a mounting element, preferably annular, at one end, which rests on the step between the first and second housing sections.The mounting element can preferably be designed as a sealing element, thus sealing the filter assembly in the second housing section so that the oil flow passes completely through the filter. In this way, the filter assembly advantageously provides the corresponding seal as an integrated component. The mounting element can be made of a soft plastic and, for example, be designed like an O-ring. Alternatively or additionally, a separate sealant can be used on the stage, or the stage itself can be designed to provide a seal.

[0017] Furthermore, the housing can have an insertion opening in a wall of the second housing section, the insertion opening being closed by a sealing element of the filter assembly. The insertion opening is preferably located opposite the step and thus the transition to the first housing section. If the filter assembly is not yet inserted into the housing of the oil suction device, the housing thus has three openings. An advantage of this insertion opening is that the filter assembly can be inserted easily and conveniently by the user and, if necessary, removed and replaced. The sealing element, which, like the mounting element, can also be designed as a sealant, advantageously closes the housing when the filter assembly is inserted. Therefore, a simple, two-part design of the oil suction device is conceivable, which is cost-effective to provide and manufacture.

[0018] In a further preferred embodiment of the invention, an insertion frame enclosing the sieve can be arranged in the receiving space to hold the sieve assembly. An advantage of this holding frame is that it provides stability to the sieve assembly, thereby preventing, for example, the wire mesh of the sieve from bending when the sieve assembly is inserted into the second housing section of the oil suction device. Furthermore, it improves handling, for example, when assembling the oil suction device.

[0019] The insertion frame can advantageously encompass the mounting element, the locking element, and at least one retaining rib connecting them. This provides a user-friendly and stable component whose insertion frame already includes all the necessary means for interaction with the housing as a further component. In a preferred embodiment, the inner wall of the second housing section, which is particularly cylindrical, has a groove extending from the step to the insertion opening. This groove can be designed such that at least one retaining rib of the sieve assembly can be inserted into it, creating a positive fit between the housing and the sieve assembly.Preferably, the sieve assembly has two retaining ribs arranged opposite and parallel to each other, so that these can be inserted into two grooves that also extend opposite and parallel to each other along the inner wall of the second housing section between the stage and the insertion opening. This arrangement offers the advantage that the sieve assembly can be mounted in the housing in a rotationally fixed manner, which in particular also keeps at least one retaining rib out of the oil flow path. Furthermore, the grooves and retaining ribs can serve as a guide for inserting the sieve assembly into the housing of the oil intake device.

[0020] Furthermore, the second housing section and the sieve assembly can have cooperating fastening means for securing the sieve assembly, wherein the fastening means can, in particular, include snap-fit ​​and / or clip fasteners. The fastening means can, for example, be attached, at least partially, to the locking element of the sieve assembly and the insertion opening of the second housing section. For instance, the insertion opening can have a groove into which a projection of the locking element can be inserted, so that the locking element is positively connected to the insertion opening. Alternatively or additionally, corresponding fastening means on the mounting element of the sieve assembly and the step in the housing are also conceivable.In the specific embodiments described above, the sieve device can therefore be inserted into the receiving space, in particular by means of the retaining ribs and their associated grooves, until the mounting element sits on the step, the closing element closes the insertion opening and at the same time the fastening means engage with each other to connect the sieve device and the housing.

[0021] The housing can be made of a plastic, particularly a glass fiber reinforced plastic. This design offers the advantage that the housing can be manufactured as a single, cohesive component using a cost-effective injection molding process, thus eliminating the need for a complex welding process in which an upper part of the housing has to be welded to a lower part. A further advantage is that the housing can consist of several different plastic components if required.

[0022] The invention further relates to a motor vehicle comprising an electric drive motor and an oil circuit for cooling the electric drive motor, wherein the oil circuit includes at least one oil intake device according to the invention. All embodiments relating to the oil intake device according to the invention can be transferred analogously to the motor vehicle according to the invention and vice versa, so that the advantages already mentioned can also be obtained with the motor vehicle. In particular, the oil circuit can have an oil tank from which oil is drawn for transport in the circuit by means of the oil intake device. The use of an oil circuit for an electric drive motor of a motor vehicle has the advantage that the oil can serve for both lubrication and cooling.

[0023] Further advantages and details of the present invention will become apparent from the exemplary embodiments described below and from the drawings. These show: Fig. 1 a schematic representation of a sieve device according to the invention, which has a mounting element, a frustoconical sieve, two retaining ribs and a closing element, Fig. 2 a schematic representation of a housing comprising a first, second and third housing section, Fig. 3 a sectional view parallel to the longitudinal axis, of the first and second housing sections through the housing and the sieve device inserted into the second housing section, Fig. 4 a sectional view perpendicular to the longitudinal axis of the first and second housing sections, through the housing and the sieve device inserted into the second housing section, viewed from the insertion opening, and Fig. 5 a schematic representation of a motor vehicle according to the invention.

[0024] Fig. Figure 1 shows a sieve device 1 and Fig. 2 a housing 16 for an oil intake device 2 according to the invention (see Fig. 3 and Fig. 4) in a motor vehicle 25 (see Fig. 5), wherein the oil drawn in by the oil intake device 2 is used for cooling and lubricating an electric drive motor 26. The oil intake device 2 is therefore installed in an oil tank 27 of an oil circuit 28.

[0025] The sieve assembly 1 has a cylindrical shape, with one end of the cylinder 3 comprising an annular mounting element 4 and the other end a lid-shaped closure element 5. The outer edge 6 of the annular mounting element 4 can rest on the step 7 formed at the transition from a first housing section 8 to a second housing section 9. One end of a sieve 11 is attached to the edge 10 of the annular mounting element 4 facing the closure element 5. The opening of the sieve 11 is the same size as the inner opening of the annular mounting element 4 to which it is attached. The other end of the sieve 11 is attached to the lid-shaped closure element 5. The sieve 11 is shaped as a truncated cone 12, such that it tapers from the mounting element 4 to the point where it is attached to the closure element 5.This creates a space between the wall of the second housing section 9 and the sieve 11, in which the sieve 11, with its enlarged sieve area due to its shape, can be surrounded by water and any filtered-out particles can collect. Alternatively, the sieve 11 can also be cylindrical or completely conical, or have a combination of such shapes. It can also have a corrugated surface to further increase the sieve area.

[0026] The locking element 5 has a projection 13 that fits into a corresponding groove 14 of an insertion opening 15 in the housing 16 in a form-fitting manner. The groove 14 and the projection 13 form fastening means for holding the sieve assembly 1 and act, for example, as a locking or clip mechanism when the sieve assembly 1 is inserted. Two opposing, parallel retaining ribs 17 are arranged between the mounting element 4 and the locking element 5. The mounting element 4, the locking element 5, and the retaining ribs 17 arranged between them together form an insertion frame 23 for the sieve 11, which encloses it.

[0027] Fig. Figure 2 shows the housing 16 for the oil intake device 2 according to the invention, wherein the housing 16 comprises the first housing section 8, the second housing section 9, and a third housing section 18, all of which are at least substantially cylindrical and hollow. The first housing section 8 has a discharge opening through which the drawn-in oil can be conveyed. Furthermore, the first housing section 8 has a groove 19 on its outer surface, which serves as a mounting interface for an oil supply line, in particular a hose with a clamp. The second housing section 9 has a receiving chamber 20, which is designed to precisely accommodate the filter device 1. The second housing section 9 rests against the first housing section 8 along a longitudinal axis 21 common with the first housing section 8.On the opposite side of stage 7 to the first housing section 8, the insertion opening 15 is arranged in the second housing section 9, which serves to insert the sieve unit 1 into the housing 16. The insertion opening 15 has the annular groove 14 into which the corresponding projection 13 of the locking element 5 can be inserted, so that the sieve unit 1 can be positively connected to the housing 16. The third housing section 18 has an intake opening 24 and lies transversely to the common longitudinal axis 21 of the first and second housing sections 8, 9 against the second housing section 9.

[0028] Fig. Figure 3 shows a sectional view along the longitudinal axis 21 of the housing 16, showing the sieve assembly 1 inserted into the housing 16. The housing 16 and the sieve assembly 1 fitted therein together form the oil intake device 2. The sieve assembly 1 was inserted precisely into the receiving chamber 20 of the second housing section 9 via the insertion opening 15. The mounting element 4 of the sieve assembly 1 rests against the step 7, which separates the first housing section 8 from the second housing section 9. To form the step 7 adjacent to the second housing section 9, the second housing section 9 has a larger inner diameter than the first housing section 8. The mounting element 4 can rest against the step 7 and seal the sieve assembly 1 against the step 7.Alternatively or additionally, the mounting element 4 can also have fastening means, in particular snap-fit ​​and clip-fit ​​fasteners, which connect the sieve assembly 1 to the housing 16 via the mounting element 4. The closure element 5 is connected to the second housing section 9 via a snap-fit ​​connection 13, 14 at the insertion opening 15. The sieve assembly 1 is inserted into the receiving space 20 of the second housing section 9 such that the sieve is arranged transversely relative to the third housing section 18, in particular perpendicular to the intake direction, with the longitudinal axis of the truncated cone 12, which here corresponds to the longitudinal axis 21 due to the central insertion.

[0029] Fig. Figure 4 shows a sectional view perpendicular to the longitudinal axis 21 of the housing 16, depicting the sieve assembly 1 inserted into the housing 16, as seen from the insertion opening 15. The retaining ribs 17, which are arranged between the mounting element 4 and the closing element 5 and are opposite each other, are inserted into grooves 22 provided for the retaining ribs 17. These grooves extend along the inner wall of the second housing section 9 between the step 7 and the insertion opening 15, thus ensuring that the sieve assembly 1 is also rotationally fixed to the housing 16. The grooves 22, corresponding to their receiving function for the retaining ribs 17, are also located opposite and parallel to each other on the inner wall of the second housing section 9.

[0030] With a sieve area of ​​1050 mm 2For example, housing 16 can have dimensions of 25 x 30 x 41 mm. In a comparative example, a flat sieve placed over the intake opening has a smaller sieve area of ​​700 mm². 2 However, a larger housing with dimensions of 48 x 35 x 32 mm is required.

[0031] In the Fig. In the assembled embodiment of the oil intake device 2, shown in a sectional view 3, the oil is drawn from the oil tank 27 via the intake opening 24 of the third housing section 18 and then strikes the sieve 11 perpendicularly, allowing it to be washed around. This filter removes impurities and other particles from the oil. The oil then flows along the longitudinal axis 21 of the first and second housing sections 8, 9 to the opening of the first housing section 8, to which an oil supply line is attached. From there, the oil can be routed through the cooling circuit, for example, for an electric drive motor 26.

[0032] Fig.Figure 5 shows the schematic arrangement of the oil tank 27, the oil circuit 28, and the electric drive motor 26 within the motor vehicle 25. The oil is drawn from the oil tank 27 via the oil intake device 2, through which it is conveyed in the oil circuit 28 and finally reaches the electric drive motor 26 via lines 29, which is cooled and lubricated by the flowing oil. The oil is then returned from the electric drive motor 26 to the oil tank 27 via further lines 29. For the sake of clarity, other components of the oil circuit 28, such as heat exchangers, pumps, and the like, are not shown. 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] EP 3 278 857 A1

[0004] CN 210714591U

[0005]

Claims

[1] Oil intake device (2) for an oil circuit (28) designed for cooling an electric drive motor (26) of a motor vehicle (25), wherein the oil intake device (2) comprises a housing (16) with - an intake opening (24), - an interior space through which oil flows, and - a mounting interface for an oil supply line, and a filter device (1) with a filter (11) for filtering the oil flowing through the intake opening (24), characterized by , that the sieve device (1) is arranged inside the housing (16), wherein the sieve (11) has a curved surface to increase the surface area. [2] Oil intake device (2) according to claim 1, characterized by , that the sieve (11) has a conical, frustoconical and / or cylindrical shape. [3] Oil intake direction (2) according to claim 2, characterized by, that the longitudinal axis (21) of the sieve (11) is arranged transversely to an intake direction of the intake opening (24), in particular perpendicular to it, in the housing (16). [4] Oil intake device (2) according to any one of the preceding claims, characterized by , that the surface of the sieve (11) has a corrugated shape. [5] Oil intake direction (2) according to any one of the preceding claims, characterized by , that the housing (16) has at least two housing sections (8, 9), wherein a first housing section (8) includes the mounting interface for the oil guide line and a second housing section (9), adjoining the first housing section (8), includes a receiving space (20) for the sieve device (1). [6] Oil intake device (2) according to claim 5, characterized by, that the transition from the first housing section (8) to the second housing section (9) has a step (7), wherein a mounting element (4) of the sieve device (1) is mounted on the step (7). [7] Oil intake device (2) according to claim 5 or 6, characterized by , that the housing (16) has an insertion opening (15) in a wall of the second housing section (9), wherein the insertion opening (15) is closed by a closing element (5) of the sieve device (1). [8] Oil intake device (2) according to any one of claims 5 to 7, characterized by , that an insertion frame (23) surrounding the sieve (11) is arranged in the receiving space (20) to hold the sieve device (1). [9] Oil intake device (2) according to claim 6, 7 and 8, characterized by , that the insertion frame (23) comprises the mounting element (4), the locking element (5) and at least one retaining rib (17) connecting them. [10] Oil intake device (2) according to any one of claims 5 to 9, characterized by , that the second housing section (9) and the sieve assembly (1) have cooperating fastening means for fastening the sieve assembly (1). [11] Oil intake device (2) according to claim 10, characterized by that the fasteners include snap-fit ​​and / or clip fasteners. [12] Oil intake device (2) according to any one of the preceding claims, characterized by , that the housing (16) is made of a plastic, in particular a glass fiber reinforced plastic. [13] Motor vehicle (25) comprising an electric drive motor (26) and an oil circuit (28) for cooling the electric drive motor (26), wherein the oil circuit (28) comprises at least one oil intake device (2) according to any one of claims 1 to 12.

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