Electric pump and temperature control system

Abstract

The invention relates to an electric pump (200) for pumping a medium, in particular a liquid, comprising a stator (210) with a stator winding (212) arranged in a dry chamber (202), a rotor (220) arranged in a wet chamber (201), a conveying unit (230) non-rotatably connected to the rotor (220) for drawing in and discharging the medium, and a housing component (240) in thermal contact with components (210, 350) of the pump (200) to be cooled, wherein the housing component (240) at least partially surrounds the stator (210) on a side of the stator (210) facing away from the rotor (220), and wherein the housing component (240) is provided as a deep-drawn component. Furthermore, a temperature control system (300) with such a pump (200) is proposed.

Description

[0001] The present invention relates to an electric pump and a temperature control system, in particular for a vehicle, with such a pump. Background of the invention

[0002] Electric pumps conventionally consist of an electric motor with a stator and a rotor that carries the pump's conveying mechanism. An example of such a pump is in Fig. 1 shown and labelled as 100 in total.

[0003] The rotor 120, together with the pumping unit 130, is arranged in a wet chamber 101 (i.e., a cavity through which the medium to be pumped flows at least temporarily and / or partially or completely), while the stator 110 is typically arranged in a dry chamber 102, i.e., outside the wet chamber 101. The wet chamber 101 is separated from the dry chamber 102 by a substantially hollow cylindrical component 160 (also referred to as a "pot"). These components can conventionally be housed together in a pump casing 140. For example, the pump casing 140 can have a shell 144 that radially encloses the stator 110, a dry-chamber cover 146, and a wet-chamber cover 142.

[0004] The pump housing 140 can conventionally be designed to mount the pump 100 to a higher-level structure, and in particular relative to the components supplied with the medium to be pumped by the pump. The power electronics and / or control electronics 150 that supply the pump can also be housed within the pump housing 140. Typically, the pump housing 140 can also be designed to dissipate heat from the stator 110 and any other components 150. In the comparative example shown here, the dry-space-side cover 146 is equipped with cooling fins, and a thermal interface material 170, for example, thermal paste, is introduced between the components 110 and 150 to be cooled and the cover 146. The dry-space-side cover 146 can, for example, be provided as an aluminum die-cast part in conventional pumps 100 to ensure sufficient cooling efficiency for the electronics 150.Alternatively, conventional pumps can also have water cooling integrated into the lid 146 (not shown here).

[0005] To prevent the medium being pumped from entering the dry chamber 102 or leaking from the wet chamber 101 into the environment, several seals 145 are typically provided, particularly at the connection point between the jacket 144 and the dry-chamber-side cover 146 of the pump housing 140, as well as between the reservoir 160 and the jacket 144 and between the reservoir 160 and the wet-chamber-side cover 142. In the comparative example shown, an inlet 181 and an outlet 185 are integrated into the wet-chamber-side cover 142, through which the medium being pumped can be drawn in and discharged by the pumping unit 130. The components 142, 144, and 146 of the pump housing 140 are each fastened to one another by means of screws 148. Disclosure of the invention

[0006] According to the invention, an electric pump and a temperature control system, particularly for a vehicle, are proposed, comprising such a pump with the features of the independent claims. Advantageous embodiments are the subject of the dependent claims and the following description.

[0007] To improve upon the state of the art, the invention proposes to design a housing component, which is in thermal contact with components of the pump to be cooled, in particular with the stator and / or the power electronics, as a deep-drawn part made from a sheet metal part. Such a design of the housing component allows heat to be efficiently dissipated from the components to be cooled, thus eliminating the need for a conventional pump housing, in particular the housing cover mentioned above designed for cooling the electronics.

[0008] Deep-drawn components offer significant advantages over conventionally used cast parts in terms of manufacturing costs and also in terms of tooling and labor requirements. In particular, deep-drawing tools wear out more slowly than casting tools. Furthermore, after the production of a deep-drawn part, no lengthy cooling time is required; the component can be immediately demolded and further processed.

[0009] In detail, an electric pump for pumping a medium, in particular a liquid, is proposed, which has a stator with a stator winding arranged in a dry room, a rotor arranged in a wet room, a conveying unit connected to the rotor in a rotationally fixed manner for drawing in and discharging the medium, and a housing component designed as a deep-drawn component, wherein the housing component is designed to dissipate heat from the stator and / or from at least one other component of the pump, in particular a power and / or control electronics supplying current to the stator.

[0010] According to at least one embodiment, the housing component is further designed to separate the dry chamber from the wet chamber, at least partially or at least at one point. This allows the housing component to come into contact with the medium pumped by the pump, at least in certain areas, and thus to transfer at least some of the heat dissipated from the stator and / or other components to the medium. This results in particularly efficient cooling of the respective components that are in thermal contact with the housing component.

[0011] The housing component can act as a seal with a canned tube located between the rotor and stator, so that a section of the housing component, together with the canned tube, forms a pot that separates the wet chamber from the dry chamber. This simplifies the manufacturing of the housing component by deep drawing, as the entire separation between the wet and dry chambers does not need to be achieved by the housing component itself. As is known, a canned tube is a tube that separates the rotor and stator or is located in the (air) gap between the rotor and stator.

[0012] According to at least one embodiment, the housing component is further configured to support the stator and to support or dissipate at least a large portion (i.e., more than 50%, preferably more than 75%) or all of the torque acting on the stator. The torque acting on the stator arises, for example, from the fact that a medium conveyed by a pump's conveying mechanism opposes the conveying mechanism with a flow resistance caused by inertia and friction.

[0013] Furthermore, a temperature control system is proposed which includes such a pump and at least one component which is supplied with the medium by the pump, wherein the at least one component is configured to absorb heat from the medium and / or to release heat to the medium.

[0014] According to at least one embodiment, the dry chamber houses electronics that supply and / or control the stator. This allows for particularly short cable runs and an overall compact design. Connections between the electronics and the stator or stator windings can be made, for example, using IDC (insulation displacement contact) or EPT (press-fit technology).

[0015] As previously mentioned, the housing component is specifically designed to transfer heat from the stator and / or (if present in the dry chamber) the electronics to the medium in the wet chamber. This ensures efficient cooling of the thermally relevant components without any additional design effort. In particular, no dedicated cooling is required for the components thermally connected to the medium in the wet chamber via the housing component. Optionally, a thermal interface medium (TIM; e.g., an aluminum-containing thermal paste) can be introduced between the housing component and the stator or electronics to ensure uniform and reliable heat conduction.For example, the housing component can have a material with high specific thermal conductivity at the respective thermal contact points (for example, in the form of heat-conducting profiles made of a second material with a higher thermal conductivity than the first, which are incorporated into a first material of the housing component). This further increases the efficiency of heat transfer.

[0016] According to at least one embodiment, the housing component has a toothed connection for a rotationally fixed connection to the stator. This allows higher torques to be transmitted from the stator via the housing component, thereby increasing the maximum pumping capacity that can be provided by the pump.

[0017] According to at least one embodiment, the housing component has a bearing for supporting a bearing pin for the rotor. The bearing can, for example, provide a fixed clamping for the bearing pin. The rotor, in turn, can be rotatably mounted on the bearing pin, for example by means of one or more rolling or sliding bearings. This allows the housing component to absorb not only the torque from the stator but also loads from the rotor.

[0018] According to at least one embodiment, the housing component has a bearing for supporting a rotor shaft. The bearing can be in the form of a rolling or sliding bearing and can be directly connected to the housing component, e.g., pressed in or bonded by a material connection.

[0019] According to at least one embodiment, the aforementioned temperature control system is connected to the pump via an inlet and an outlet, which may be integrated into a wet-side cover of the pump. In particular, the wet-side cover may support the housing component and be designed to counteract the torque of the stator transmitted through the housing component. The wet-side cover of the pump thus functions as both a fluidic and a mechanical connection between the pump and the rest of the temperature control system. Furthermore, the wet-side cover may be designed for mechanically fixing the pump (e.g., by bolting it to other components of the temperature control system or to a device encompassing the temperature control system).

[0020] According to at least one embodiment, the housing component is pressed and / or screwed and / or positively locked and / or materially bonded to the wet-room-side cover. These are particularly stable and at the same time easy-to-manufacture connections.

[0021] According to at least one embodiment, a seal is arranged between the housing component and the wet-side cover, sealing the wet area against the dry area and / or the pump's surroundings. This ensures the long-term functionality of the pump or the temperature control system with minimal maintenance.

[0022] Alternatively, the housing component can be designed so that no seal is required between the housing component and the wet-side cover, meaning that it acts as a seal with the cover. In particular, the housing component can also be fluid-tightly attached to the aforementioned canned tube and / or fluid-tight to a connector housing that may be used to power the electronics, thus eliminating the need for separate seals, such as O-rings. This further reduces the cost of the pump.

[0023] According to at least one embodiment, the wet-side cover is further designed to at least partially separate the dry chamber from the pump's surroundings. This protects the stator and, if applicable, the electronics located in the dry chamber from external influences (e.g., dust, moisture, mechanical impacts, etc.).

[0024] Regardless of the design of the wet-side cover, a (dry-side) cover may be provided which is attached to the wet-side cover and / or the housing component and separates the dry room from the pump's environment, for example to prevent moisture and / or contaminants (e.g. dust) from entering the dry room.

[0025] Regardless of the specific design of the temperature control system, the medium pumped by the pump can be used to temperature-control a component of the system before being returned to the pump. For this purpose, the temperature control system can, for example, include one or more heat exchangers that transfer heat from the medium to a component being cooled (to heat the component) and / or transfer heat from a component being cooled to the medium (to cool the component). Alternatively or additionally, one or more heat exchangers can be provided that transfer heat from the medium to the surrounding environment of the temperature control system and / or vice versa.

[0026] In at least one embodiment, one or more of such components to be temperature-controlled may be a component of a vehicle, for example a drive unit, in particular an electric one, and / or a traction battery and / or a vehicle cabin and / or a computing unit, e.g. a vehicle control unit.

[0027] Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawing.

[0028] The invention is schematically illustrated in the drawing using exemplary embodiments and is described below with reference to the drawing. Brief description of the drawings Fig. Figure 1 shows a comparative example of an electric pump not in accordance with the invention, in an exploded view and a perspective view. Fig. Figure 2 shows an embodiment of an electric pump, as it can be used in embodiments of the invention, in a schematic side sectional view, and Fig. 3 another embodiment of an electric pump according to the invention. embodiment(s) of the invention

[0029] Fig. 1 has already been described in the introduction.

[0030] In Fig. Figure 2 is an embodiment of an electric pump, as it can be used in embodiments of the invention, shown in a schematic side sectional view and designated overall by 200.

[0031] The pump 200 has a stator 210 with a stator winding 212 in a dry chamber 202. A rotor 220 is arranged inside the stator 210 in a wet chamber 201. The stator 210 and rotor 220 together form an electric motor that drives the pump 200. The rotor 220 can, in particular, have permanent magnets; in other words, the electric motor is, in particular, a permanent magnet motor.

[0032] The wet chamber 201 is separated from the dry chamber 202 by a substantially hollow cylindrical canned tube 260 and a housing component 240 that seals against the canned tube. The housing component 240 is designed to mechanically support the stator 210 and may, in particular, have a toothing 265 that can, for example, engage with corresponding teeth on the stator core.

[0033] Furthermore, a conveyor 230, which is rotationally fixed to the rotor 220, is arranged in the wet room 201. For example, the conveyor 230 can be in the form of a paddle wheel or a turbine. The rotor 220 itself is rotatably mounted relative to the stator 210. In the example shown here, a bearing pin 225 is rigidly fixed or clamped in the housing component 240, with a bearing 227, for example a rolling bearing or a plain bearing, which allows relative rotation between the bearing pin 225 and the rotor 220, being arranged between the rotor 220 and the bearing pin 225.

[0034] The canned tube 260 can, for example, be made partially or completely of a thermoplastic material (for example, using a casting process and / or an additive manufacturing process) and / or can be manufactured using one or more metallic materials, such as aluminum or (stainless) steel (for example, by pressing from a sheet and / or using a casting process and / or an additive manufacturing process). The housing component 240 is provided as a deep-drawn component, for example, from a metal sheet, in particular an aluminum sheet or a steel sheet, in particular a stainless steel sheet, and, in the example shown, projects into the wet chamber 202 with a first heat exchange surface 248. This allows the housing component 240 to transfer heat to the medium flowing through the wet chamber 202. Depending on the material pairing, the housing component 240 can be welded, bonded, or soldered to the canned tube 260, for example.Alternatively, a seal between the slotted tube 260 and the housing component 240 can also be achieved by mechanically clamping the two parts against each other.

[0035] From the in Fig. The pump 200 differs from the conventional pump 100 shown in Figure 1, in particular in that the housing component 240 supporting the stator 210 is in direct contact with the fluid pumped by the pump, and therefore no heat dissipation via the housing cover on the dry-space side (also referred to here as the cover 320) is required. Therefore, conventional designs require a heat sink and thus a structurally and materially complex housing cover 146, whereas designs according to the invention can do without such an external heat sink and can therefore use a significantly less complex housing cover 320.

[0036] The pump 200, as it is in Fig. As shown in 2, is with a lid 142 of the conventional pump 100 made of Fig. 1 essentially identical wet-room-side cover, which is also designated 142, mechanically and fluidically connected and via this wet-room-side cover 142 connected to further components of a respective temperature control system (here designated 300).

[0037] In the example shown, a seal 345, for example an elastomer seal such as an O-ring, is arranged between the slotted tube 360 ​​and a sealing surface of the cover 142 to seal the wet chamber 201 against the environment of the pump 200 and / or against the dry chamber 202. However, as already mentioned, with a suitable design of the housing component 240, this seal 345 can also be omitted, particularly if a section 249 of the housing component 240 (which interacts with the cover 142 instead of the slotted tube 260 as shown here) is manufactured with sufficient precision to fulfill the sealing function. For this purpose, the deep-drawn component 240 can optionally be post-processed, for example by machining (e.g., milling, turning, grinding, honing, etc.) to achieve sufficient surface quality with regard to geometry and / or surface finish (flatness, roughness, etc.).

[0038] Furthermore, in the example shown, a cover 320 is provided, which separates the dry chamber 202 of the pump 200 from the surrounding environment and is mechanically connected to a jacket 144 that surrounds the housing component 240 in this example. In the example shown, a connector housing 250 for the electrical supply of the pump 200 is integrated into the jacket 144. This connector housing is fluid-tightly connected to the housing component 240, thus preventing the ingress of fluids (and therefore also other contaminants such as dust) into the dry chamber 202 from outside the pump 200. In contrast to the example shown, the jacket surrounding the housing component on a side facing away from the stator 210 can be formed integrally, in particular monolithically, with the canned tube 260, which offers advantages with regard to sealing the wet chamber 201 from the dry chamber 202.For example, this one-piece component can be provided as an injection-molded part made from a thermoplastic material.

[0039] In the example shown, in addition to the stator 210, an electronics unit 350 (e.g., in the form of a printed circuit board populated with electronic components) is arranged in the dry chamber 202. This unit supplies the stator 210 with electrical energy and / or controls the stator 210. In the examples shown here, this electronics unit 350 is arranged on an end face of the housing component 240 and is in thermal contact with the housing component 240, so that the housing component 240 can transfer heat from the electronics unit 350 to the medium flowing around the section 248. To improve the efficiency of this heat transfer, a thermally conductive medium 370, for example, a thermal paste containing metallic aluminum, is introduced between the electronics unit 350 and the housing component 240.

[0040] In Fig.Figure 3 shows the embodiment of the electric pump 200 housing component 240, which is designed as a pot-shaped deep-drawn component. The housing component 240 has an axial extension 24, the outer diameter of which is smaller than the outer circumferential wall 244 of the housing component 240, which abuts radially on the outside of the stator 210. The axial extension 24 has a base surface 26, which is circular in this case and is in axial thermal contact with the circuit board 30 of the electronics 350. Radially around this base surface 26, offset at an axial distance, an annular base ring 28 is arranged, which extends radially to the circumferential wall 244 of the housing component 240.The housing component 240 thus has a stepped base 25, with a sufficiently large installation space formed between the annular base ring 28 and the circuit board 30 to accommodate even larger electronic components 31 on the circuit board 30 in relation to the stator 210. The annular base ring 28 preferably extends over the entire radial extent of the stator 210 with the electrical stator winding 212. Thus, the outer circumferential wall 244 is in direct radial thermal contact with the stator base body 21, and the base surface 26 of the axial extension 24 is in direct axial thermal contact with the circuit board 30. Axially opposite the circuit board 30, the base surface 26 forms an inner wall of the wet chamber 201 and is directly exposed to the liquid cooling medium. This effectively cools both the circuit board 30 and the stator base body 21.To form the wet chamber 201, the canned tube 260 is inserted radially inside the axial extension 24 into a bearing seat 20 and sealed liquid-tight against the inner wall of the axial extension 24. The canned tube 260 then extends axially over the entire axial dimension of the stator 210. At the end axially opposite the bottom surface 26, the canned tube 260 has an annular cover surface 249 that radially covers the stator 210. The annular cover surface 249 then transitions axially on the outside of the stator 210 into the shell 144, which then axially overlaps the circumferential wall 244 of the housing component 240 in the region of the stator base body 21. The casing 144 is sealed liquid-tight against the cover 142, so that the stator 210 with the electronics 350 is sealed as a dry room 202 against the wet room 201 of the rotor 220.In the region of the axial extension 24, a bearing receptacle 40 for the rotor 220 is formed radially within the slotted tube 260. For example, a rotor shaft 22 is fixedly fixed in the bearing receptacle 40, with the rotor 220 and the conveyor 230 then rotatably mounted on the rotor shaft 22. In particular, the slotted tube 260 is formed integrally with the bearing receptacle 40, for example, as a plastic injection-molded component. Axial openings 44 are formed between the bearing receptacle 40 and the inner surface of the base surface 26 to allow the cooling medium to flow onto the base surface 26. The base surface 26 of the axial extension 24 is flat over its entire diameter and is in full thermal contact with the electronic circuit board 30.

[0041] Regardless of the specific design of the temperature control system 300, the medium pumped by the pump 200 can be used to temperature-control a component of the temperature control system 300 (not shown separately in the figure) before being returned to the pump 200. For this purpose, the temperature control system 300 can, for example, have one or more heat exchangers (not shown) that transfer heat from the medium to a component to be temperature-controlled (for heating the component) and / or transfer heat from a component to be temperature-controlled to the medium (for cooling the component). Alternatively or additionally, one or more heat exchangers can be provided that transfer heat from the medium to an environment surrounding the temperature control system 300 and / or vice versa.

[0042] In at least one embodiment, one or more of such components to be temperature-controlled may be a component of a vehicle, for example a drive unit, in particular an electric one, and / or a traction battery and / or a vehicle cabin and / or a computing unit, e.g. a vehicle control unit.

Claims

[1] Electric pump (200) for pumping a medium, in particular a liquid, comprising: a stator (210) with a stator winding (212) arranged in a dry room (202), a rotor (220) which is arranged in a wet room (201), a conveyor (230) connected to the rotor (220) in a rotationally fixed manner for drawing in and discharging the medium, and a housing component (240) that is in thermal contact with components (210, 350) of the pump (200) to be cooled, wherein the housing component (240) at least partially surrounds the stator (210) on a side of the stator (210) facing away from the rotor (220), and wherein the housing component (240) is provided as a deep-drawn component. [2] Electric pump (200) according to claim 1, further comprising a canned tube (260) arranged between the stator (210) and the rotor (220) and configured to cooperate with the housing component (240) to separate the dry chamber (202) from the wet chamber (201). [3] Electric pump (200) according to claim 2, wherein the canned tube (260) is formed in one piece, in particular monolithically, with a jacket (144) which at least partially surrounds the housing component (240) on a side facing away from the stator (210), and the jacket (144) extends in particular axially approximately to the center of a stator base body (21) of the stator (210). [4] Electric pump (200) according to one of the preceding claims, wherein the housing component (240) is configured to support the stator (210) and to dissipate a torque acting on the stator (210). [5] Electric pump (200) according to one of the preceding claims, wherein an electronics unit (350) supplying and / or controlling the stator (210) is arranged in the dry room (202), which has an electronic circuit board (30). [6] Electric pump (200) according to one of the preceding claims, wherein the housing component (240) is configured to dissipate heat from the stator (210) and / or, with reference to at least claim 5, the electronics (350) to transfer to the medium in the wet room (201). [7] Electric pump (200) according to one of the preceding claims, wherein the housing component (240) has a toothing (265) for connecting the housing component (240) to the stator (210) in a rotationally fixed manner. [8] Electric pump (200) according to one of the preceding claims, wherein the housing component (240) is made at least partially from a metal sheet, in particular an aluminium sheet and / or a steel sheet and / or a stainless steel sheet, preferably as a pot-shaped component, the bottom (25, 26) of which rests against the electronic circuit board (30). [9] Electric pump (200) according to one of the preceding claims, wherein the housing component (240) has a bearing for supporting a bearing pin (225) for the rotor, wherein in particular the rotor (220) is rotatably mounted on the bearing pin (225). [10] Electric pump (200) according to one of the preceding claims, comprising a wet-room-side cover (142) which is configured to supply the medium to the pump (200) and / or to discharge the medium from the pump (200). [11] Electric pump (200) according to claim 10 with reference to at least claim 4, wherein the wet-room-side cover (142) supports the housing component (240) and is configured to support the torque of the stator (210) derived through the housing component (240). [12] Electric pump (200) according to claim 10 or 11, wherein the housing component (240) is pressed and / or screwed and / or positively connected and / or materially connected to the wet room-side cover (142). [13] Electric pump (200) according to one of the preceding claims, wherein the housing component (240) has an axial extension (24) whose bottom surface (26) is thermally contacted with the electronic circuit board (30), and the electronic circuit board (30) extends radially beyond the outer circumference of the axial extension (24), and in particular a free installation space is formed radially next to the axial extension (24) and in the axial region of the axial extension (24) in which at least one electronic component (31) of the electronic circuit board (30) can be arranged if required. [14] Electric pump (200) according to one of the preceding claims, wherein the inside of the axial extension (24) forms a cylindrical bearing seat (20) for receiving the slotted tube (260), which is in particular sealed against liquids from the bearing seat (20). [15] Electric pump (200) according to one of the preceding claims, wherein the bottom (25) of the housing part (240) has an annular bottom ring (28) around the bottom surface (26) of the axial extension (24), which is arranged axially offset to the bottom surface (26) of the axial extension (24), and in particular the bottom ring (28) extends in the radial direction over the entire radial extent of the stator (210). [16] Electric pump (200) according to one of the preceding claims, wherein a bearing receptacle (40) for the rotor shaft (22) is formed radially within the slotted tube (260) - in particular monolithically with it - and in particular the bearing receptacle (40) projects axially into the axial extension (24). [17] Temperature control system (300) comprising an electric pump (200) according to one of the preceding claims and at least one component which is supplied with the medium by the pump (200), wherein the at least one component is configured to absorb heat from the medium and / or to release heat to the medium.

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