In-wheel motor integrated cooler

Abstract

The application provides a hub motor integrated cooler and belongs to the technical field of cooling devices.The application comprises: a gas-tight container which is opened in the interior of a hub motor, is used for packaging a cooling working medium, has a steam outlet and a liquid return port; a bubble pump which is laid on the inner wall surface of the gas-tight container and is used for driving the cooling working medium to transport to the upper part of the gas-tight container; a motor coil which is laid on the outer wall surface of the gas-tight container close to the outside; and an electric control chip which is arranged on the wall surface of the gas-tight container and has the cooling working medium at the mounting position thereof.The application packages the cooling working medium in the gas-tight container, installs the electric control chip and the motor coil on different surfaces of the gas-tight container to cool, and lays the bubble pump on the inner wall surface of the gas-tight container.The bubble pump drives the gas-liquid two-phase to transport to the high place by using the buoyancy in the rising process of the bubbles, so that the hub motor is uniformly cooled as a whole.

Description

Technical Field

[0001] This invention relates to the field of cooling device technology, and more particularly to an integrated cooler for hub motors. Background Technology

[0002] The main characteristic of in-wheel motor technology for new energy vehicles is the integration of the vehicle's drive motor into the wheel hub. This high level of integration reduces the number of transmission components, offering advantages such as flexible control, high degree of freedom, energy saving, and small footprint. However, a major obstacle to the development of in-wheel motors is the poor heat dissipation and overheating problems resulting from this high integration. Cooling methods for new energy in-wheel motors can be broadly categorized into three types: air cooling, liquid cooling, and phase change cooling.

[0003] However, existing cooling methods for new energy wheel hub motors all suffer from technical problems such as poor cooling effect, low integration, and high equipment weight. Summary of the Invention

[0004] In view of this, to address the technical problems of poor cooling effect and low integration in existing new energy wheel hub motor cooling methods, this invention provides an integrated wheel hub motor cooler. This cooler utilizes a hermetically sealed container designed to fit the shape of the wheel hub motor to encapsulate the cooling medium, achieving efficient cooling of the wheel hub motor (including the electronic control chip and motor coils) through phase change heat transfer of the cooling medium. The working medium boils in the cooler, generating vapor. This vapor is led out through the vent to the condenser, where it condenses into liquid and returns to the cooler through the return port, forming a cycle. A bubble pump is installed on the inner wall of the hermetically sealed container. The bubble pump uses the rising airflow generated by the bubbles to drive the cooling medium upwards, thereby ensuring relatively uniform cooling of the entire wheel hub motor.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] Integrated cooler for in-wheel motors, including:

[0007] An airtight container, located inside the hub motor, is used to encapsulate the cooling medium and has a steam outlet and a liquid return port.

[0008] A bubble pump, which is installed on the inner wall of the airtight container, is used to drive the cooling medium to transport to the upper part of the airtight container.

[0009] The motor coil is laid on the outer wall surface of the airtight container near the outer side;

[0010] An electronic control chip is disposed on the wall of the airtight container and the cooling medium is present at its mounting position.

[0011] Preferably, the bubble pump includes a first bubble pump, which is disposed on the inner wall surface of the airtight container near the outer side.

[0012] Preferably, the electronic control chip is laid on the outer wall surface of the airtight container near the inner side, and the working fluid is indirectly heated and cooled by the wall surface to make it boil, and a high thermal conductivity metal plate is laid on its outer side.

[0013] Preferably, the inner side of the inner wall of the airtight container is provided with a liquid-absorbing core for enhancing boiling heat transfer.

[0014] Preferably, a suction core can be installed on the heated wall surface of the bubble pump. The suction core should be a porous structure with strong liquid absorption capacity, such as foam metal material, sintered metal wire mesh, sintered metal felt, or other materials with micron-scale pores. The capillary phenomenon within the suction core can promote liquid supply towards the height of the heated wall.

[0015] Preferably, a second bubble pump is provided on the inner wall surface near the inner side of the airtight container.

[0016] Preferably, the electronic control chip and the high thermal conductivity metal plate extend to the upper middle part of the airtight container.

[0017] Preferably, the airtight container has an insertion hole for inserting the electronic control chip, and the insertion hole is immersed in the cooling medium.

[0018] Preferably, the amount of the cooling working fluid is 30% to 70% of the height of the airtight container.

[0019] Preferably, the first bubble pump is composed of multiple parallel narrow flow paths.

[0020] Preferably, thermal grease is coated on both sides of the electronic control chip.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The integrated cooler for hub motors provided by this invention utilizes the shape of the hub motor to create an airtight container inside, encapsulating the cooling medium. This allows for efficient cooling through the phase change heat transfer of the cooling medium. Furthermore, by increasing the integration between the hub motor (including the electronic control system) and the cooling system, the overall cooling performance is improved while the total system weight is reduced, resulting in a comprehensive performance enhancement for the hub motor cooling system. The hub motor's electronic control chip and motor coils, among other heat-generating components, are mounted at different locations on the outer surface of the airtight container. Heat is indirectly transferred to the cooling medium through the heat conduction of the container wall, cooling each component individually. A bubble pump is installed on the inner wall of the airtight container. The bubble pump uses the rising airflow generated by the bubbles to drive the cooling medium upwards, thus ensuring relatively uniform cooling of the entire hub motor.

[0023] The integrated cooler for hub motors provided by this invention achieves efficient transport of the cooling medium against gravity by laying a bubble pump on the inner side of the cooler wall and combining it with a porous liquid suction core, which can further improve the cooling effect. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the first type of integrated cooler for hub motors.

[0025] Figure 2 This is a schematic diagram of the structure of the second type of integrated cooler for hub motors;

[0026] Figure 3 This is a schematic diagram of the third type of integrated cooler for hub motors.

[0027] Figure 4 This is a schematic diagram of the fourth type of integrated cooler for hub motors.

[0028] Figure 5 for Figure 4 Sectional view of AA;

[0029] Figure 6 for Figure 4 Sectional view of BB;

[0030] Figure 7 for Figure 4 Another shape for the insertion hole in the cross-sectional view of BB;

[0031] Figure 8 A schematic diagram of the structure of the first or second bubble pump;

[0032] Figure 9 This is a schematic diagram illustrating an improved arrangement of the electronic control chip in this invention;

[0033] In the diagram, 1. Hub motor, 11. Airtight container, 111. Steam outlet, 112. Liquid return port, 113. Cooling medium, 12. Outer wall surface, 121. Outer side of the outer wall surface, 122. Inner side of the outer wall surface, 13. Inner wall surface, 131. Outer side of the inner wall surface, 132. Inner side of the inner wall surface, 2. First bubble pump, 3. Motor coil, 4. Electronic control chip, 5. High thermal conductivity metal plate, 6. Liquid suction core, 7. Second bubble pump, 8. Insertion hole. Detailed Implementation

[0034] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0035] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] This invention addresses the phase change cooling technology of hub motors in new energy vehicles, proposing a highly integrated cooler. Its main cooling targets are two: (1) the hub motor's electronic control chip, such as IGBT chips, SiC chips, and GaN chips; and (2) the motor coil. In this invention, the motor coil is installed on the outer side of the outer wall for cooling. The electronic control chip can be installed at different locations on the cooler, and it is electrically connected to the hub motor via wires. Based on the different installation locations of the electronic control chip, the cooler can be divided into two main types. The first type is the chip-mounted cooler, whose structure is as follows: Figure 1-3 As shown; the second type is the chip insertion type cooler, whose structure is as follows. Figure 4 As shown.

[0038] like Figure 1 As shown, this hub motor integrated cooler, as the most basic integrated cooler, is described below. Figure 2-4 The hub motor integrated cooler shown is in this Figure 1 Further improvements based on the existing foundation.

[0039] like Figure 1 As shown, the integrated cooler for hub motors provided by the present invention includes:

[0040] An airtight container 11 is located inside the hub motor 1 and connected to an external condenser via a pipeline. It is used to encapsulate the cooling medium 113. It has a steam outlet 111 (connected to the condenser to generate steam from boiling and lead it to the condenser) and a liquid return port 112 (connected to the condenser to allow the condensate to flow back to the container 11). The airtight container 11 should have strict airtightness and may be an annular airtight container.

[0041] A bubble pump, installed on the inner wall of the airtight container 11, is used to drive the cooling medium 113 to be transported to the upper part of the airtight container 11. The airtight container 11 has an outer wall surface 12 and an inner wall surface 13.

[0042] The wall surfaces that come into contact with the airtight container 11 and the cooling working medium 11 are collectively referred to as the inner wall surface 13, and the wall surfaces outside the inner wall surface 13 are collectively referred to as the outer wall surface 12.

[0043] The outer side of the inner wall surface 13 is called the outer side 131 of the inner wall surface (the wall surface in contact with the cooling medium 113), and the inner side of the inner wall surface 13 is called the inner side 132 of the inner wall surface (the wall surface in contact with the cooling medium 113).

[0044] The outer side of the outer wall surface 12 is called the outer outer wall surface 121 (corresponding to the outer side 131 of the inner wall surface), and the inner side is called the inner outer wall surface 122 (corresponding to the inner side 132 of the inner wall surface).

[0045] The motor coil 3 is laid on the outer wall 121 of the airtight container 11 near the outer side, preferably installed in close contact;

[0046] The electronic control chip 4 is disposed on the wall of the airtight container 11, and the inner side 132 of the inner wall corresponding to its installation position should have the cooling medium 113. The installation position height is preferably lower than the filling liquid level of the cooling medium to ensure indirect contact with the cooling medium. The electronic control chip 4 can be disposed on the outer wall 122 of the inner side of the airtight container 11 or on the inner side 132 of the inner wall. Since the airtight container 11 is annular, in addition to the outer wall 12 and inner wall 13 mentioned above, its wall also has two annular surfaces on both sides. The electronic control chip 4 can also be disposed on the two annular surfaces on both sides of the airtight container 11. Those skilled in the art can select the installation position of the electronic control chip 4 according to actual needs.

[0047] The integrated cooler for the hub motor provided by this invention has a cooling medium 113 located in the lower half of the airtight container 11 due to gravity. To promote heat transfer in the upper half, a bubble pump is used to transport the cooling medium 113 to the upper part of the container. The bubble pump uses the buoyancy flow generated during the rising of bubbles to drive the cooling medium to a higher position, thereby making the hub motor 113 more uniformly cooled as a whole.

[0048] In this invention, the bubble pump includes a first bubble pump 2, which is disposed on one side of the inner wall surface 13 of the airtight container, preferably disposed on the outer side 131 of the inner wall surface.

[0049] like Figure 1 As shown, in this invention, the electronic control chip 4 is laid on the outer wall surface 122 near the inner side of the airtight container 11, and a high thermal conductivity metal plate 5 with strong thermal conductivity is laid on its outer side. The high thermal conductivity metal plate 5 is preferably a copper plate. This method, in which the electronic control chip 4 is attached to the inner outer wall surface 122, can be named a chip-attached type cooler. An arc-shaped copper pressure plate is added to the electronic control chip 4 as the high thermal conductivity metal plate 5 and presses the electronic control chip 4 tightly. The high thermal conductivity metal plate 5 plays two roles: (1) reducing the contact thermal resistance between the electronic control chip 4 and the cooling surface by applying pressure; (2) becoming a thermal bridge between the heat-generating surface and the cooling surface. By installing the high thermal conductivity metal plate 5, the heat conduction from the electronic control chip 4 to the cooler can be strengthened as a whole, promoting the cooling effect on both sides of the electronic control chip 4. The electronic control chip 4 is preferably a plurality of square flat pieces with a side length of about 1cm to 4cm. Both the front and back surfaces of the electronic control chip 4 are heating surfaces. In order to reduce the contact thermal resistance between the two sides of the electronic control chip 4 and the cooler and the high thermal conductivity metal plate 5, the gap is preferably filled with a filler (thermal grease) with high thermal conductivity to promote heat conduction.

[0050] like Figure 2 As shown, based on the first method, the present invention provides a liquid-absorbing core 6 (preferably a porous structure) for enhancing boiling heat transfer on the inner side 132 of the inner wall of the airtight container 11 as a second improvement, thereby promoting the cooling of the electronic control chip 4. The liquid-absorbing core 6 has a strong liquid-absorbing capacity and also functions to enhance boiling heat transfer and assist the bubble pump (the second bubble pump in the third improvement method) in transporting liquid to higher levels. It can be a material with micron-scale pores, such as foamed metal material, sintered metal mesh, or sintered metal felt.

[0051] like Figure 3As shown, as a third improvement, the present invention, based on the first improvement, provides a second bubble pump 7 on the other side of the inner wall surface 13 of the airtight container 11 to facilitate the supply of coolant to the upper part, thereby cooling the electronic control chip installed at a higher position. The second bubble pump 7 is preferably identical in structure to the first bubble pump 2.

[0052] In this invention, a second bubble pump 7 is provided on the other side of the inner wall surface 13 of the airtight container 11, preferably the second bubble pump 7 is provided on the inner side 132 of the inner wall surface.

[0053] Because a bubble pump is installed on the inner wall, in this improved method, the electronic control chip 4 does not need to be laid to the lower middle part of the airtight container 11, but can be installed at a higher position (above the liquid level of the filling coolant). Specifically, in this invention, the electronic control chip 4 and the high thermal conductivity metal plate 5 extend to the upper middle part of the airtight container 11, so that more electronic control chips 4 can be installed on the inner outer wall 122 (the electronic control chips 4 installed in the upper middle part of the airtight container 11 have no coolant inside at the corresponding position).

[0054] like Figure 4-7 As shown, as a fourth improvement, based on the first method, the present invention provides an insertion hole 8 on the airtight container 11 for inserting the electronic control chip 4. The insertion hole 8 is preferably in an inverted T-shape (e.g., ...). Figure 7 (as shown) or L-shaped (such as) Figure 6 As shown, the insertion hole 8 is immersed in the cooling medium 113. Since the cooling medium 113 has a certain liquid level, the position of the insertion hole 8 cannot be higher than the liquid level of the cooling medium 113. This is equivalent to the insertion hole 8 being immersed in the cooling medium 113.

[0055] In this fourth improvement, to enhance the cooling of the heating surfaces on both sides of the electronic control chip 4, the electronic control chip 4 is not attached to the outer surface of the inner wall. Instead, a narrow insertion hole 8 is made at the bottom of the airtight container 11, and the electronic control chip 4 is inserted into it for cooling. There is no need to use a porous body or a second bubble pump 7 to enhance heat transfer on the inner side of the inner wall. The insertion hole 8 should be immersed in the coolant, and thermal grease is applied between the surface of the electronic control chip 4 and the surface of the insertion hole 8 to enhance heat conduction. Using this structure, both surfaces of the electronic control chip 4 can be efficiently cooled by boiling (a porous surface can be added to enhance boiling heat transfer as needed).

[0056] In addition, the inner outer wall surface 122 still... Figure 1-3 The cooler structure is the same as shown, and the coolant is supplied from bottom to top using the first bubble pump 2.

[0057] In this invention, the filling amount of the cooling medium 113 is 30% to 70% of the height of the airtight container 11. Before filling, the air inside the airtight container 11 is removed by evacuation. The cooling medium 113 can be Novec 7100 (electronic fluorinated liquid), water, or alcohol, etc., selected according to the range of operating temperature and pressure.

[0058] like Figure 8 As shown, in this invention, the first bubble pump 2 is composed of multiple parallel narrow flow paths, and the cross-section of the flow path is preferably rectangular.

[0059] like Figure 8 As shown, in this invention, the second bubble pump 7 is composed of multiple parallel narrow flow paths.

[0060] In this invention, the first bubble pump 2 and the second bubble pump 7 preferably have the same structure, both consisting of multiple parallel narrow flow paths. Their cross-sectional shape is not specified, but a square with a side length of approximately 1 to 3 mm is preferred. To ensure close contact with the heat transfer surface, the first bubble pump 2 and the second bubble pump 7 should have the same radius of curvature as the corresponding wall surface of the airtight container 11 and be pressed tightly together during installation.

[0061] In this invention, thermal grease is coated on both sides of the electronic control chip 4 to enhance heat transfer.

[0062] Figure 9 This is an improved arrangement of the electronic control chip in this invention. To better ensure close contact between the chip and the cooler wall, the electronic control chip can be arranged on the flat wall surface of the cooler, such as two annular flat wall surfaces perpendicular to the outer wall surface 12 and the inner wall surface 13. This improved method still utilizes a high thermal conductivity metal plate to press the electronic control chip against the cooling wall surface, and the performance of the inner wall surface of the cooler where the electronic control chip is arranged can be optimized using methods such as bubble pumps and liquid suction cores.

[0063] The above are merely preferred embodiments of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concept, should be covered within the scope of protection of the present invention.

Claims

1. An integrated cooler for hub motors, characterized in that, include: An airtight container, located inside the hub motor, is used to encapsulate the cooling medium and has a steam outlet and a liquid return port. The airtight container is ring-shaped; A bubble pump, which is installed on the inner wall of the airtight container, is used to drive the cooling medium to transport to the upper part of the airtight container. The motor coil is laid on the outer wall surface of the airtight container near the radial outer side; An electronic control chip is disposed on the wall of the airtight container and the cooling medium is present at its mounting position.

2. The integrated cooler for wheel hub motors according to claim 1, characterized in that, The bubble pump includes a first bubble pump, which is disposed on one side of the inner wall of the airtight container.

3. The integrated cooler for wheel hub motors according to claim 2, characterized in that, A second bubble pump is provided on the other side of the inner wall of the airtight container.

4. The integrated cooler for wheel hub motors according to claim 1, characterized in that, The electronic control chip is laid on the outer wall surface of the airtight container near the radial inner side, and a high thermal conductivity copper plate is laid on its outer side.

5. The integrated cooler for wheel hub motors according to claim 4, characterized in that, The inner wall surface of the airtight container on the radially inner side is covered with a liquid-absorbing core for enhancing boiling heat transfer.

6. The integrated cooler for wheel hub motors according to claim 4, characterized in that, The electronic control chip and the high thermal conductivity copper plate extend to the upper middle part of the airtight container.

7. The integrated cooler for wheel hub motors according to claim 1, characterized in that, The airtight container has an insertion hole for inserting the electronic control chip, and the insertion hole is immersed in the cooling medium.

8. The integrated cooler for wheel hub motors according to claim 1, characterized in that, The amount of cooling medium is 30% to 70% of the height of the airtight container.

9. The integrated cooler for hub motors according to claim 2, characterized in that, The first bubble pump consists of multiple parallel narrow flow paths.

10. The hub motor integrated cooler according to any one of claims 1-9, characterized in that, The two sides of the electronic control chip are coated with thermal grease.

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