Heat dissipation structure and electronic apparatus

Abstract

This application provides a heat dissipation structure and an electronic device. The heat dissipation structure may include a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, and the magnetic device may be located between the circuit board and the heat sink. The magnetic device may include a magnetic core and a film-wrapped cable, the magnetic core includes a stopper and a central magnetic cylinder that are fastened together, the film-wrapped cable is wound around the central magnetic cylinder, and the film-wrapped cable is electrically connected to the circuit board. In the heat dissipation structure, a thermally conductive film may be disposed on at least a part of a side surface of the stopper. In this way, temperature uniformity of the magnetic device can be effectively improved, so that a problem of a local high temperature of the magnetic device is resolved. In addition, the thermally conductive medium may be disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device. In this case, heat generated by the magnetic device may be conducted to the thermally conductive medium and then transferred to the heat sink for heat dissipation. This can effectively improve heat dissipation efficiency of the heat dissipation structure, so that performance of an electronic device in which the heat dissipation structure is disposed is improved.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Chinese Patent Application No. 202211362569.3, filed with the China National Intellectual Property Administration on November 2, 2022 and entitled "HEAT DISSIPATION STRUCTURE AND ELECTRONIC DEVICE", which is incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] This application relates to the field of heat dissipation technologies, and in particular, to a heat dissipation structure and an electronic device.BACKGROUND

[0003] With development of electronic technologies, density of power devices in electronic devices continuously increases, and layouts of power devices on circuit boards become increasingly compact. As a result, heat flux density on the circuit boards also increases. If no good heat dissipation measure is taken, application scenarios of the power devices are limited, and product performance of the electronic devices is also limited.

[0004] Magnetic devices, such as an inductor and a transformer, are used as examples, and the magnetic devices are important devices for implementing power conversion. These magnetic devices may usually each include a magnetic core and a copper wire wound around the magnetic core. However, an insulation film is usually added to the copper wire, to implement insulation of the copper wire. In this case, an overall thickness of the copper wire wrapped around the magnetic core is large. As a result, a heat dissipation path from the magnetic core to a heat sink is long. In addition, because a thermal conductivity coefficient of a magnetic material is low, it is very difficult for heat generated at the magnetic core to spread outward. As a result, in a windless scenario, a temperature difference between an inner layer and an outer layer of the copper wire of the magnetic device is large, and heat dissipation at the magnetic core usually becomes a bottleneck of heat dissipation of these magnetic devices.SUMMARY

[0005] This application provides a heat dissipation structure and an electronic device, to improve heat dissipation efficiency of the heat dissipation structure, so that performance of the electronic device is improved.

[0006] According to a first aspect, this application provides a heat dissipation structure, where the heat dissipation structure may include a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, and the magnetic device may be located between the circuit board and the heat sink. The magnetic device may include a magnetic core and a film-wrapped cable, the magnetic core includes a stopper and a central magnetic cylinder that are fastened together, the film-wrapped cable is wound around the central magnetic cylinder, and the film-wrapped cable is electrically connected to the circuit board. In the heat dissipation structure, a thermally conductive film may be disposed on at least a part of a side surface of the stopper. The thermally conductive film is disposed on the side surface of the stopper. In this way, temperature uniformity of the magnetic device can be effectively improved, so that a problem of a local high temperature of the magnetic device can be resolved. This reduces an over-temperature risk of the magnetic core. In addition, the thermally conductive medium may be disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device. In this case, heat generated by the magnetic device may be conducted to the thermally conductive medium, and then transferred to the heat sink for heat dissipation, so that heat dissipation efficiency of the heat dissipation structure can be effectively improved.

[0007] In a possible implementation of this application, in addition to the side surface of the stopper, a thermally conductive film may be further disposed on a surface of the central magnetic cylinder, and the film-wrapped cable is in thermal contact with the thermally conductive film. In this way, heat generated by the film-wrapped cable and the central magnetic cylinder may be conducted to the thermally conductive film, so that temperature uniformity of the magnetic device can be further improved.

[0008] In addition, when the thermally conductive film is disposed between the central magnetic cylinder and the film-wrapped cable, the film-wrapped cable and the thermally conductive film may be further wound around the central magnetic cylinder alternately. This may help increase a contact area between the film-wrapped cable and the thermally conductive film. In this way, temperature uniformity at the central magnetic cylinder can be improved, and heat dissipation efficiency of the heat dissipation structure can be effectively improved.

[0009] In this application, a specific type of the thermally conductive medium is not limited, and the thermally conductive medium may be, for example, a thermally conductive adhesive. The thermally conductive adhesive is filled between the magnetic device and the heat sink, so that the thermally conductive adhesive wraps at least a part of the thermally conductive film. This facilitates heat conduction between the thermally conductive film and the thermally conductive adhesive. It may be understood that, the thermally conductive film is disposed on the magnetic core, so that temperature uniformity of the magnetic core can be improved. In this way, heat dissipation efficiency of the heat dissipation structure can be improved, and usage of the thermally conductive adhesive can be effectively reduced, so that costs of the heat dissipation structure can be reduced.

[0010] When the thermally conductive adhesive wraps at least a part of the thermally conductive film, the thermally conductive adhesive may further wrap at least a part of the magnetic core and at least a part of the film-wrapped cable. This helps improve temperature uniformity of the magnetic device.

[0011] In a possible implementation of this application, a thermally conductive film may be further disposed on a surface that is of the stopper and that faces the heat sink. In this way, an area of the thermally conductive film disposed on the magnetic core can be effectively increased, so that an objective of improving temperature uniformity of the magnetic core can be achieved.

[0012] In this application, a specific type of the thermally conductive film is not limited, and the thermally conductive film may be, for example, a metal thin film with good thermal conductivity performance, such as copper foil. Alternatively, the thermally conductive film may be a non-metallic thin film with good thermal conductivity performance, such as a graphite film.

[0013] According to a second aspect, this application further provides a heat dissipation structure, where the heat dissipation structure may include a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, and the magnetic device may be located between the circuit board and the heat sink. The magnetic device may include a magnetic core and a film-wrapped cable, the magnetic core includes a stopper and a central magnetic cylinder that are fastened together, the film-wrapped cable is wound around the central magnetic cylinder, and the film-wrapped cable is electrically connected to the circuit board. In the heat dissipation structure, a thermally conductive film may be disposed on at least a part of a surface of the central magnetic cylinder. The thermally conductive film is disposed on the surface of the central magnetic cylinder. In this way, temperature uniformity of the magnetic device can be effectively improved, so that a problem of a local high temperature of the magnetic device can be resolved. This reduces an over-temperature risk of the magnetic core. In addition, the thermally conductive medium may be disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device. In this case, heat generated by the magnetic device may be conducted to the thermally conductive medium, and then transferred to the heat sink for heat dissipation, so that heat dissipation efficiency of the heat dissipation structure can be effectively improved.

[0014] In addition, when the thermally conductive film is disposed between the central magnetic cylinder and the film-wrapped cable, the film-wrapped cable and the thermally conductive film may be further wound around the central magnetic cylinder alternately. This may help increase a contact area between the film-wrapped cable and the thermally conductive film. In this way, temperature uniformity at the central magnetic cylinder can be improved, and heat dissipation efficiency of the heat dissipation structure can be effectively improved.

[0015] According to a third aspect, this application further provides a heat dissipation structure, where the heat dissipation structure may include a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, and the magnetic device may be located between the circuit board and the heat sink. The magnetic device may include a magnetic core and a film-wrapped cable, the magnetic core includes a stopper and a central magnetic cylinder that are fastened together, the film-wrapped cable is wound around the central magnetic cylinder, and the film-wrapped cable is electrically connected to the circuit board. In the heat dissipation structure, a thermally conductive film is disposed between the film-wrapped cable and the central magnetic cylinder, and the film-wrapped cable and the thermally conductive film are wound around the central magnetic cylinder alternately. The film-wrapped cable and the thermally conductive film are wound around the central magnetic cylinder alternately, so that a contact area between the thermally conductive film and the film-wrapped cable is large. In this way, temperature uniformity of the magnetic device can be effectively improved, so that a problem of a local high temperature of the magnetic device can be resolved. This reduces an over-temperature risk of the magnetic core. In addition, the thermally conductive medium may be disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device. In this case, heat generated by the magnetic device may be conducted to the thermally conductive medium, and then transferred to the heat sink for heat dissipation, so that heat dissipation efficiency of the heat dissipation structure can be effectively improved.

[0016] According to a fourth aspect, this application further provides an electronic device, where the electronic device may include a housing and the heat dissipation structure according to the first aspect, and the heat dissipation structure may be disposed in the housing. The heat dissipation structure of the electronic device has good heat dissipation performance, so that performance of the electronic device can be improved. This helps improve product competitiveness of the electronic device.BRIEF DESCRIPTION OF DRAWINGS

[0017] FIG. 1 is a diagram of a structure of a layout of a magnetic device according to this application; FIG. 2 is a diagram of an existing heat dissipation structure of a magnetic device according to this application; FIG. 3 is a diagram of another existing heat dissipation structure of a magnetic device according to this application; FIG. 4 is a diagram of a structure of a heat dissipation structure according to an embodiment of this application; FIG. 5 is a diagram of a partial structure of a magnetic device in FIG. 4; FIG. 6 is a sectional view of a heat dissipation structure according to another embodiment of this application; FIG. 7 is a sectional view of a heat dissipation structure according to another embodiment of this application; FIG. 8 is a diagram of a partial structure of a magnetic device in FIG. 7; FIG. 9 is a sectional view of a heat dissipation structure according to another embodiment of this application; and FIG. 10 is a diagram of a partial structure of a magnetic device in FIG. 9. Reference numerals:

[0018] 1: magnetic device; 101: magnetic core; 1011: stopper; 1012: central magnetic cylinder; 1013: thermally conductive film; 102: film-wrapped cable; 103: thermally conductive medium; 103a: thermally conductive pad; 103b: thermally conductive adhesive; 104: magnetic air gap; 2: circuit board; 3: heat sink. DESCRIPTION OF EMBODIMENTS

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following further describes embodiments of this application in detail with reference to the accompanying drawings. Reference to "an embodiment", "some embodiments", or the like described in this specification indicates that one or more embodiments of this application include a specific feature, structure, or characteristic described with reference to embodiments. Therefore, statements such as "in an embodiment", "in some embodiments", "in some other embodiments", and "in other embodiments" that appear at different places in this specification do not necessarily mean referring to a same embodiment. Instead, the statements mean "one or more but not all of embodiments", unless otherwise specifically emphasized in another manner. In addition, terms such as "first" and "second" in this specification are merely used for distinction in description, and should not be understood as an indication or implication of relative importance or an indication or implication of a sequence.

[0020] For ease of understanding a heat dissipation structure provided in embodiments of this application, the following first describes an application scenario of the heat dissipation structure. The heat dissipation structure may be used in, but is not limited to, a magnetic device that is configured to implement power conversion, such as an inductor and a transformer. The magnetic device may usually include a magnetic core and a film-wrapped cable, and the film-wrapped cable is wound around the magnetic core. The film-wrapped cable may be a cable with a copper wire in the middle and an insulation film wrapped around the cable.

[0021] FIG. 1 is a diagram of a structure of a layout of a magnetic device according to an embodiment of this application. The magnetic device 1 may be usually disposed on a circuit board 2, and is electrically connected to the circuit board 2. For example, the circuit board 2 may be a printed circuit board (printed circuit board, PCB), so that the circuit board 2 can stably carry the magnetic device 1. As power density of an electronic device increases, a layout of the circuit board 2 becomes increasingly compact. As a result, heat flux density of the circuit board 2 becomes increasingly high. A good heat dissipation measure helps implement a function of the magnetic device 1, so that performance of the electronic device can be effectively improved, and product competitiveness can be improved.

[0022] Currently, there are some solutions for heat dissipation of the magnetic device 1. FIG. 2 is a diagram of an existing heat dissipation structure of a magnetic device 1 according to an embodiment of this application. In the heat dissipation structure, the magnetic device 1 may be located between a circuit board 2 and a heat sink 3, and the magnetic device 1 is attached to the heat sink 3 through a thermally conductive pad 103a. The thermally conductive pad 103a has good thermal conductivity performance and can absorb assembly tolerance. A process of the heat dissipation solution is simple, and costs are low. However, because thermal conductivity coefficients of a magnetic core 101 and a film-wrapped cable 102 of the magnetic device 1 are low, along a direction from the circuit board 2 to the heat sink 3, a temperature difference of the magnetic device 1 is large. This is mainly reflected in a fact that a temperature of a part that is of the magnetic device 1 and that is close to the circuit board 2 is greater than a temperature of a part that is of the magnetic device 1 and that is close to the heat sink 3. In this case, heat dissipation is only performed by using one side, and as a result, a heat dissipation capability of the magnetic device 1 is poor.

[0023] To reduce the temperature difference of the magnetic device 1, reference may be made to FIG. 3. FIG. 3 is a diagram of another existing heat dissipation structure of a magnetic device 1 according to an embodiment of this application. In the heat dissipation structure, a thermally conductive adhesive 103b is filled in gaps between a film-wrapped cable 102 and a magnetic core 101 of the magnetic device 1 and between the magnetic device 1 and a heat sink 3, so that temperature uniformity of the magnetic device 1 is improved, and thermal resistance between the magnetic device 1 and the heat sink 3 can be effectively reduced. In this way, a heat dissipation requirement of the magnetic device 1 is met. However, a thermal conductivity coefficient of the thermally conductive adhesive 103b is not high, and in an application scenario with high heat consumption, a temperature difference of the magnetic device 1 is still large. In this case, a circuit board 2 is still prone to an over-temperature problem.

[0024] A heat dissipation structure provided in this application is intended to resolve the foregoing problem. According to the heat dissipation structure, a thermally conductive film is added to a magnetic device, to improve overall temperature uniformity of the magnetic device, so that heat dissipation efficiency of the magnetic device is improved. This helps improve product performance of an electronic device in which the heat dissipation structure is used. The following further describes this application in detail with reference to the accompanying drawings and specific embodiments.

[0025] FIG. 4 is a diagram of a structure of a heat dissipation structure according to an embodiment of this application. The heat dissipation structure may include a circuit board 2, a magnetic device 1, and a heat sink 3. The circuit board 2 may be a PCB, the magnetic device 1 is electrically connected to the circuit board 2, and the magnetic device 1 is located between the circuit board 2 and the heat sink 3. The magnetic device 1 may include a magnetic core 101 and a film-wrapped cable 102. In this application, the magnetic core 101 is a structure formed by a magnetic material. For example, the magnetic core 101 may be a magnetic metal oxide structure formed by sintering various iron oxide mixtures.

[0026] FIG. 5 is a diagram of a partial structure of the magnetic device 1 in FIG. 4. In this application, the magnetic core 101 may include a stopper 1011 and a central magnetic cylinder 1012, and the stopper 1011 and the central magnetic cylinder 1012 are fastened together. In this application, shapes and sizes of the stopper 1011 and the central magnetic cylinder 1012 are not limited. Shapes of the stopper 1011 and the central magnetic cylinder 1012 may be the same or different, and sizes of the stopper 1011 and the central magnetic cylinder 1012 may be the same or different. This is not specifically limited in this application. For example, the stopper 1011 may be of a cylindrical structure, the central magnetic cylinder 1012 may also be of a cylindrical structure, and a radius of a cross section circle of the stopper 1011 is greater than a radius of a cross section circle of the central magnetic cylinder 1012. In addition, along a direction perpendicular to the stopper 1011 and the central magnetic cylinder 1012, a cross-sectional shape of the magnetic core 101 may be but is not limited to a T shape. The stopper 1011 and the central magnetic cylinder 1012 may be of structures with cross sections of a regular shape, such as cylindrical structures, or may be of some possible structures with cross sections of an irregular shape. This is not specifically limited in this application.

[0027] In a possible embodiment, the magnetic core 101 may be of an integrally formed structure. In other words, the central magnetic cylinder 1012 and the stopper 1011 are formed by using one process. In this way, a structure of the magnetic core 101 can be stable, and a molding process of the magnetic core 101 can be simplified. In some other possible embodiments, the central magnetic cylinder 1012 and the stopper 1011 may alternatively be of two separately formed structures, and are fastened together in a manner of sintering or the like.

[0028] The film-wrapped cable 102 may be wound around the central magnetic cylinder 1012, and the stopper 1011 of the magnetic core 101 may limit and stop the film-wrapped cable 102, to limit a position at which the film-wrapped cable 102 is disposed on the magnetic core 101, and prevent the film-wrapped cable 102 from falling off from the magnetic core 101. In this application, a cross-sectional area of the stopper 1011 may be greater than a cross-sectional area of the central magnetic cylinder 1012, so that the stopper 1011 can limit the film-wrapped cable 102. In addition, each magnetic core 101 may be wound by one or at least two film-wrapped cables 102. This may be set based on a specific application scenario, and is not limited herein.

[0029] It may be understood that, after the film-wrapped cable 102 is wound around the magnetic core 101, two cable heads of each film-wrapped cable 102 may be used as interfaces of a power device, to be electrically connected to the circuit board 2. In addition, the power device and the circuit board 2 can be fastened together through connection between the two cable heads of each film-wrapped cable 102 and the circuit board 2. In this case, the power device and the circuit board 2 can be fastened together without disposing an additional structure, so that an overall structure of the heat dissipation structure can be simplified.

[0030] In this application, to improve temperature uniformity of the heat dissipation structure, a thermally conductive film 1013 may be disposed on a surface of the magnetic core 101. The thermally conductive film 1013 may be in direct contact with the surface of the magnetic core 101, or a thermally conductive material may be filled between the thermally conductive film 1013 and the surface of the magnetic core 101, so that the thermally conductive film 1013 is in indirect contact with the surface of the magnetic core 101.

[0031] Still refer to FIG. 4 and FIG. 5. In embodiments shown in FIG. 4 and FIG. 5, during specific disposing of the thermally conductive film 1013 on the magnetic core 101, the thermally conductive film 1013 may be disposed on the stopper 1011 of the magnetic core 101, for example, may be disposed on at least a part of a side surface of the stopper 1011. The side surface of the stopper 1011 is a surface that is of the stopper 1011 and that faces away from the central magnetic cylinder 1012. The thermally conductive film 1013 is disposed on the side surface of the stopper 1011, so that the thermally conductive film 1013 is disposed conveniently.

[0032] In this application, a specific material of the thermally conductive film 1013 is not limited. For example, the thermally conductive film 1013 may be a metal thin film with good thermal conductivity performance, such as copper foil, or may be a non-metallic thin film with good thermal conductivity performance, such as a graphite film. In addition, in a possible embodiment of this application, the thermally conductive film 1013 may be disposed on the entire side surface of the stopper 1011, so that temperature uniformity of the magnetic device 1 is better. In some other possible embodiments of this application, the thermally conductive film 1013 may alternatively be disposed on a part of the side surface of the stopper 1011. For example, along a direction from the heat sink 3 to the circuit board 2, continuous sheet-shaped thermally conductive films 1013 may be disposed on a part of the side surface of the stopper 1011. Alternatively, the thermally conductive film 1013 may be disposed as a strip structure, and the strip-shaped thermally conductive film 1013 may extend along the direction from the heat sink 3 to the circuit board 2. In addition, there may alternatively be a plurality of strip-shaped thermally conductive films 1013, and the plurality of strip-shaped thermally conductive films 1013 are arranged side by side at intervals. The thermally conductive film 1013 is disposed on a part of the side surface of the stopper 1011. In this way, a temperature uniformity requirement of the magnetic device 1 can be met, and usage of the thermally conductive film 1013 can be reduced, so that costs of the heat dissipation structure are reduced.

[0033] Still refer to FIG. 4 and FIG. 5. In this application, in addition to the side surface of the stopper 1011, a thermally conductive film 1013 may be further disposed on a top surface of the stopper 1011. The top surface of the stopper 1011 may be a surface that is of the stopper 1011 and that faces the heat sink 3. During specific disposing of the thermally conductive film 1013 on the top surface of the stopper 1011, in a possible embodiment of this application, the thermally conductive film 1013 may be disposed on the entire top surface of the stopper 1011, to effectively improve temperature uniformity of the magnetic core 101. In some other possible embodiments of this application, the thermally conductive film 1013 may alternatively be disposed on a part of the top surface of the stopper 1011. In this case, the thermally conductive film 1013 may be in a sheet shape, a strip shape, or the like. This is not specifically limited in this application. In this way, temperature uniformity of the magnetic core 101 can be improved, and usage of the thermally conductive film 1013 can be reduced, so that costs of the heat dissipation structure are reduced.

[0034] It may be understood that, in this application, types of the thermally conductive films 1013 disposed on the side surface and the top surface of the stopper 1011 may be the same or may be different. In addition, the thermally conductive films 1013 disposed on the side surface and the top surface of the stopper 1011 may be connected, or may not be connected. This is not specifically limited in this application.

[0035] A thermally conductive medium 103 may be further disposed in the heat dissipation structure, so that heat generated at the magnetic core 101 can be conducted to the heat sink 3. The thermally conductive medium 103 may be disposed between the magnetic device 1 and the heat sink 3, and the thermally conductive medium 103 is in thermal contact with the heat sink 3 and at least a part of the magnetic device 1. A specific type of the thermally conductive medium 103 is not limited in this application, provided that the thermally conductive medium 103 has good thermal conductivity performance. For example, in the heat dissipation structure provided in the embodiment shown in FIG. 4 of this application, the thermally conductive medium 103 may be a thermally conductive adhesive 103b, and the thermally conductive adhesive 103b may be filled in a gap between the magnetic device 1 and the heat sink 3, so that the thermally conductive adhesive 103b wraps at least a part of the magnetic core 101, at least a part of the thermally conductive film 1013, and at least a part of the film-wrapped cable 102, and can implement bonding between the entire magnetic device 1 and a surface of the heat sink 3.

[0036] The heat dissipation structure provided in this embodiment of this application is used, so that heat generated by the magnetic device 1 can be conducted to the thermally conductive adhesive 103b through the thermally conductive film 1013, and then conducted to the heat sink 3 through the thermally conductive adhesive 103b for heat dissipation. Because the thermally conductive film 1013 has good thermal conductivity performance, thermal conductivity efficiency of the magnetic device 1 can be effectively improved by using the heat dissipation structure. In addition, the thermally conductive adhesive 103b is filled between the magnetic device 1 and the heat sink 3, so that thermal resistance between the magnetic device 1 and the heat sink 3 can be effectively reduced, and a heat dissipation requirement of the magnetic device 1 can be met.

[0037] It may be understood that, in this application, a filling amount of the thermally conductive adhesive 103b in the heat dissipation structure is not limited, and may be specifically adjusted based on a structure of the magnetic device 1, the heat dissipation requirement of the magnetic device 1, space between the magnetic device 1 and the heat sink 3, and the like, provided that heat generated by the magnetic device 1 can be transferred to the heat sink 3 for heat dissipation after being conducted to the thermally conductive adhesive 103b. In addition, the thermally conductive film 1013 is disposed on the magnetic core 101, so that temperature uniformity of the magnetic core 101 can be improved. In this way, usage of the thermally conductive adhesive 103b can be effectively reduced, so that costs of the heat dissipation structure can be reduced.

[0038] In a possible embodiment of this application, the thermally conductive medium 103 may alternatively be a thermally conductive pad 103a. During specific implementation, refer to FIG. 6. FIG. 6 is a diagram of a structure of a heat dissipation structure according to another embodiment of this application. The thermally conductive pad 103a may be disposed between the magnetic device 1 and the heat sink 3, and the thermally conductive pad 103a is attached to the heat sink 3 and at least a part of the magnetic device 1. In this embodiment, the thermally conductive film 1013 disposed on the stopper 1011 of the magnetic core 101, especially the thermally conductive film 1013 disposed on the side surface of the stopper 1011, may be in thermal contact with the thermally conductive pad 103a, so that heat generated by the magnetic device 1 can be conducted to the thermally conductive pad 103a through the thermally conductive film 1013, and then conducted to the heat sink 3 through the thermally conductive pad 103a for heat dissipation, to improve heat dissipation efficiency of the magnetic device 1.

[0039] It can be learned from the description of the foregoing embodiment that, the thermally conductive film 1013 with good thermal conductivity performance is disposed on the surface of the magnetic core 101, so that temperature uniformity of the magnetic device 1 can be effectively improved. This helps implement heat dissipation of the magnetic device 1. Based on this, in addition to the stopper 1011 of the magnetic core 101, the thermally conductive film 1013 may be further disposed on another part of the magnetic core 101. FIG. 7 is a sectional view of a heat dissipation structure according to another possible embodiment of this application. FIG. 8 is a diagram of a partial structure of the magnetic device 1 in FIG. 7. In this embodiment, the thermally conductive film 1013 may be disposed on at least a part of a surface of the central magnetic cylinder 1012. A material of the thermally conductive film 1013 may be, but is not limited to, a metal thin film with good thermal conductivity performance, such as copper foil, or may be a non-metallic thin film with good thermal conductivity performance, such as a graphite film. It should be noted that, when the thermally conductive film 1013 is a metal thin film, the thermally conductive film 1013 should be disposed away from a magnetic air gap 104 of the magnetic device 1, so that the magnetic device 1 can operate normally.

[0040] In the embodiment shown in FIG. 7 and FIG. 8, a thermally conductive film 1013 may be disposed on the entire surface of the central magnetic cylinder 1012, so that temperature uniformity of the magnetic device 1 is better. In some other possible embodiments of this application, a thermally conductive film 1013 may alternatively be disposed on a part of the surface of the central magnetic cylinder 1012. For example, along an axial direction of the central magnetic cylinder 1012, continuous strip-shaped thermally conductive films 1013 may be disposed on a part of the surface of the central magnetic cylinder 1012, and the strip-shaped thermally conductive films 1013 may be disposed along a circumferential direction of the central magnetic cylinder 1012.

[0041] It may be understood that, during specific disposing of the heat dissipation structure shown in FIG. 7 and FIG. 8, the thermally conductive film 1013 may be first formed on the surface of the central magnetic cylinder 1012, and then the film-wrapped cable 102 is wound around the central magnetic cylinder 1012. In this case, the film-wrapped cable 102 may also be in thermal contact with the thermally conductive film 1013, so that heat generated at the film-wrapped cable 102 can also be conducted to the thermally conductive film 1013.

[0042] Still refer to FIG. 7. The thermally conductive medium 103 may be further disposed between the magnetic device 1 and the heat sink 3, and the thermally conductive medium 103 may be, for example, the thermally conductive adhesive 103b. For a specific disposing manner of the thermally conductive adhesive 103b, refer to the embodiment shown in FIG. 4. For example, the thermally conductive adhesive 103b is in thermal contact with the heat sink 3 and at least a part of the magnetic device 1. Details are not described herein again. In addition, the thermally conductive medium 103 may alternatively be the thermally conductive pad 103a, and may be specifically disposed with reference to the embodiment shown in FIG. 6. Details are not described herein again.

[0043] The heat dissipation structure provided in the embodiment shown in FIG. 7 and FIG. 8 is used, so that temperature uniformity at the central magnetic cylinder 1012 can be effectively improved, and heat generated by the magnetic device 1 can be conducted to the thermally conductive adhesive 103b through the thermally conductive film 1013, and then conducted to the heat sink 3 through the thermally conductive adhesive 103b for heat dissipation. This can effectively improve heat dissipation efficiency of the heat dissipation structure. In addition, the thermally conductive film 1013 is disposed on the central magnetic cylinder 1012, so that temperature uniformity of the magnetic core 101 can be improved. In this way, usage of the thermally conductive adhesive 103b can be effectively reduced, so that costs of the heat dissipation structure can be reduced. In addition, the heat dissipation structure provided in this embodiment is used. This may help reduce a local high temperature of the magnetic device 1, for example, a temperature of a side that is of the magnetic device 1 and that is close to the circuit board 2, so that an over-temperature risk at the circuit board 2 can be reduced.

[0044] It may be understood that, in some possible embodiments of this application, the thermally conductive film 1013 may alternatively be disposed on the surfaces of both the stopper 1011 and the central magnetic cylinder 1012 of the magnetic core 101. The thermally conductive film 1013 on the surface of the stopper 1011 may be disposed with reference to the embodiment shown in FIG. 4, and the thermally conductive film 1013 on the surface of the central magnetic cylinder 1012 may be disposed with reference to the embodiment shown in FIG. 7. Details are not described herein again. The thermally conductive film 1013 is disposed on both the stopper 1011 and the central magnetic cylinder 1012 of the magnetic core 101, so that temperature uniformity of the magnetic core 101 can be effectively improved. This can help improve heat dissipation efficiency of the entire magnetic device 1.

[0045] In addition, because the film-wrapped cable 102 may usually include a metal wire, and in a working process of the magnetic device 1, the metal wire in the film-wrapped cable 102 may be used as a current flow channel, a large amount of heat is generated. Based on this, heat generated by the film-wrapped cable 102 may be quickly exported, to improve heat dissipation efficiency of the magnetic device 1. During specific implementation, refer to FIG. 9 and FIG. 10. FIG. 9 is a sectional view of a heat dissipation structure according to another possible embodiment of this application. FIG. 10 is a diagram of a partial structure of the magnetic device 1 in FIG. 9. In this embodiment, the film-wrapped cable 102 and the thermally conductive film 1013 are wound around the central magnetic cylinder 1012 alternately. There may be a plurality of specific implementations. For example, along the circumferential direction of the central magnetic cylinder 1012, one turn of the thermally conductive film 1013 may be first wound, and then one turn of the film-wrapped cable 102 is wound, where the thermally conductive film 1013 may be located between the film-wrapped cable 102 and the central magnetic cylinder 1012, and then the foregoing winding sequence is repeated until winding of the thermally conductive film 1013 and the film-wrapped cable 102 is completed on the entire central magnetic cylinder 1012. In some other possible embodiments of this application, alternatively, one turn of the film-wrapped cable 102 may be first wound on the central magnetic cylinder 1012, and then the thermally conductive film 1013 is wound. A winding sequence of the film-wrapped cable 102 and the thermally conductive film 1013 is not limited in this application.

[0046] Still refer to FIG. 9. The thermally conductive medium 103 may be further disposed between the magnetic device 1 and the heat sink 3, and the thermally conductive medium 103 may be, for example, the thermally conductive adhesive 103b. For a specific disposing manner of the thermally conductive adhesive 103b, refer to the embodiment shown in FIG. 4. For example, the thermally conductive adhesive 103b is in thermal contact with the heat sink 3 and at least a part of the magnetic device 1. Details are not described herein again. In addition, the thermally conductive medium 103 may alternatively be the thermally conductive pad 103a, and may be specifically disposed with reference to the embodiment shown in FIG. 6. Details are not described herein again.

[0047] The heat dissipation structure provided in the embodiment shown in FIG. 9 and FIG. 10 is used, so that both the central magnetic cylinder 1012 and the film-wrapped cable 102 can be in contact with the thermally conductive film 1013. In addition, because the thermally conductive film 1013 and the film-wrapped cable 102 are wound around the central magnetic cylinder 1012 alternately, a contact area between the film-wrapped cable 102 and the thermally conductive film 1013 can be effectively increased. In this way, temperature uniformity at the central magnetic cylinder 1012 can be effectively improved, and heat generated by the central magnetic cylinder 1012 and the film-wrapped cable 102 can be conducted to the thermally conductive adhesive 103b through the thermally conductive film 1013, and then conducted to the heat sink 3 through the thermally conductive adhesive 103b for heat dissipation. This can effectively improve heat dissipation efficiency of the heat dissipation structure. In addition, the thermally conductive film 1013 is disposed on the central magnetic cylinder 1012, so that temperature uniformity of the magnetic core 101 can be improved. In this way, usage of the thermally conductive adhesive 103b can be effectively reduced, so that costs of the heat dissipation structure can be reduced. In addition, the heat dissipation structure provided in this embodiment is used. This may help reduce a local high temperature of the magnetic device 1, for example, a temperature of a side that is of the magnetic device 1 and that is close to the circuit board 2, so that an over-temperature risk at the circuit board 2 can be reduced.

[0048] In some possible embodiments of this application, when the film-wrapped cable 102 and the thermally conductive film 1013 are wound around the central magnetic cylinder 1012 alternately, the thermally conductive film 1013 may be further disposed on the surface of the stopper 1011 and / or the surface of the central magnetic cylinder 1012 of the magnetic core 101. The thermally conductive film 1013 on the surface of the stopper 1011 may be disposed with reference to the embodiment shown in FIG. 4, and the thermally conductive film 1013 on the surface of the central magnetic cylinder 1012 may be disposed with reference to the embodiment shown in FIG. 7. Details are not described herein again. In this way, temperature uniformity of the magnetic core 101 can be effectively improved. This can help improve heat dissipation efficiency of the entire magnetic device 1. In addition, temperature uniformity of the magnetic core 101 is improved, so that an over-temperature risk of the magnetic core 101 can be effectively reduced, to improve working reliability of the magnetic device 1. Over-temperature of the magnetic core 101 is a phenomenon of an out-of-control temperature that occurs after the magnetic core 101 is magnetically saturated at a high temperature.

[0049] The heat dissipation module provided in the foregoing embodiments of this application may be used in various possible electronic devices. A specific type of the electronic device is not limited in this application. For example, the electronic device may be a power supply device such as a charging pile or an inverter, or may be a communication device such as a server or a memory, or may be another electronic device such as a vehicle or a home device. In addition to the heat dissipation structure, the electronic device may include a housing, and the heat dissipation structure may be disposed in the housing. The heat dissipation structure of the electronic device has good heat dissipation performance, and power density of the heat dissipation structure is high. In this way, performance of the electronic device can be improved. In addition, the heat dissipation structure provided in the foregoing embodiment of this application is used, so that a quantity of devices disposed on the circuit board 2 per unit area can be large. This helps implement a miniaturization design of the heat dissipation structure, so that a miniaturization design of the electronic device can be implemented.

[0050] It is clear that a person skilled in the art can make various modifications and variations to this application without departing from the scope of this application. This application is intended to cover these modifications and variations of this application provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.

Claims

1. A heat dissipation structure, comprising a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, wherein the magnetic device is located between the circuit board and the heat sink; the magnetic device comprises a magnetic core and a film-wrapped cable, the magnetic core comprises a stopper and a central magnetic cylinder, the stopper and the central magnetic cylinder are fastened together, the film-wrapped cable is wound around the central magnetic cylinder, and the film-wrapped cable is electrically connected to the circuit board; a thermally conductive film is disposed on at least a part of a side surface of the stopper, and the side surface is a surface that is of the stopper and that faces away from the central magnetic cylinder; and the thermally conductive medium is disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device.

2. The heat dissipation structure according to claim 1, wherein the thermally conductive film is disposed on at least a part of a surface of the central magnetic cylinder, and the film-wrapped cable is in thermal contact with the thermally conductive film.

3. The heat dissipation structure according to claim 1 or 2, wherein the thermally conductive film is disposed between the film-wrapped cable and the central magnetic cylinder, and the film-wrapped cable and the thermally conductive film are wound around the central magnetic cylinder alternately.

4. The heat dissipation structure according to any one of claims 1 to 3, wherein the thermally conductive medium is a thermally conductive adhesive, and the thermally conductive adhesive wraps at least a part of the thermally conductive film.

5. The heat dissipation structure according to claim 4, wherein the thermally conductive adhesive wraps at least a part of the magnetic core and at least a part of the film-wrapped cable.

6. The heat dissipation structure according to any one of claims 1 to 5, wherein the thermally conductive film is disposed on a surface that is of the stopper and that faces the heat sink.

7. The heat dissipation structure according to any one of claims 1 to 6, wherein the thermally conductive film is copper foil or a graphite film.

8. A heat dissipation structure, comprising a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, wherein the magnetic device is located between the circuit board and the heat sink; the magnetic device comprises a magnetic core and a film-wrapped cable, the magnetic core comprises a stopper and a central magnetic cylinder, the stopper and the central magnetic cylinder are fastened together, and the thermally conductive film is disposed on at least a part of a surface of the central magnetic cylinder; and the film-wrapped cable is wound around the central magnetic cylinder, and the film-wrapped cable is in thermal contact with the thermally conductive film; and the thermally conductive medium is disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device.

9. The heat dissipation structure according to claim 8, wherein the thermally conductive film is disposed between the film-wrapped cable and the central magnetic cylinder, and the film-wrapped cable and the thermally conductive film are wound around the central magnetic cylinder alternately.

10. A heat dissipation structure, comprising a circuit board, a magnetic device, a heat sink, and a thermally conductive medium, wherein the magnetic device is located between the circuit board and the heat sink; the magnetic device comprises a magnetic core and a film-wrapped cable, the magnetic core comprises a stopper and a central magnetic cylinder, the stopper and the central magnetic cylinder are fastened together, a thermally conductive film is disposed between the film-wrapped cable and the central magnetic cylinder, and the film-wrapped cable and the thermally conductive film are wound around the central magnetic cylinder alternately; and the thermally conductive medium is disposed between the magnetic device and the heat sink, and the thermally conductive medium is in thermal contact with the heat sink and at least a part of the magnetic device.

11. An electronic device, comprising a housing and the heat dissipation structure according to any one of claims 1 to 10, wherein the heat dissipation structure is disposed in the housing.

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