Patent Description:
An inductor is one of components commonly used in a circuit. The inductor generates a specific amount of heat in a working process. Especially for a power inductor, when a relatively high current flows through an inductor winding of the inductor, a relatively large amount of heat is generated. If the heat is accumulated near an inductor coil of the inductor winding for a long time and cannot be effectively dissipated, working stability of the inductor is affected. An existing inductor usually uses a potting process in which an inductor winding is disposed in a housing, a thermally conductive packaging material is potted inside, heat generated by the inductor winding is transferred to the housing through the thermally conductive packaging material, and then the heat is dissipated through the housing. In an existing solution, a same thermally conductive packaging material is usually injected into the housing. To achieve better heat dissipation effect, a thermally conductive packaging material with a relatively good heat-conducting property needs to be potted in the housing. The thermally conductive packaging material with a relatively good heat-conducting property is usually at relatively high costs, and consequently there are relatively high manufacturing costs for the inductor. In addition, a material with relatively high heat dissipation performance usually has relatively high density, resulting in a relatively great increase in an overall weight of a system. The <CIT> refers to encapsulated electrical components in a housing with an insulating resin involves adding only a small amount of foaming agent to obtain layers of different density. The <CIT> refers to a heat dissipation type transformer and inductor. The <CIT> refers to a reactor device. The <CIT> refers to a reactor embedment device. <CIT> discloses a coil component for an electric vehicle having mold portions having electrical insulation, to cover two coils individually, in which a modulus of elasticity of a secondary mold portion is less than a modulus of elasticity of a primary mold portion.

This application provides an inductor with relatively good heat dissipation effect, relatively low <NUM> manufacturing costs, and a relatively light weight.

According to the present invention there is provided an inductor according to present claim <NUM>. The inductor includes an inductor winding, a housing, and a thermally conductive packaging material. The inductor winding is disposed in the housing. The thermally conductive packaging material is potted in the housing to fill a gap between the inductor winding and the housing. The thermally conductive packaging material includes a first packaging layer and a second packaging layer, and a coefficient of thermal conductivity of the first packaging layer is greater than a coefficient of thermal conductivity of the second packaging layer. The housing includes a heat dissipation wall and a packaging wall, and the first packaging layer is closer to the heat dissipation wall than the second packaging layer.

The housing includes the heat dissipation wall and the packaging wall, and the heat dissipation wall has better heat dissipation effect than the packaging wall. Therefore, most of heat generated by the inductor winding is dissipated through the heat dissipation wall, and less heat is dissipated through the packaging wall. A material whose coefficient of thermal conductivity is greater than that of the second packaging layer is used for the first packaging layer close to the heat dissipation wall with a relatively large heat dissipation coefficient, so that it can be ensured that most of the heat generated by the inductor winding can be quickly transmitted to the housing through the first packaging layer with good heat-conducting effect, to ensure relatively good heat dissipation for the inductor. In addition, a part of a region that is in the housing and that is far away from the heat dissipation wall is filled with the second packaging layer with relatively poor heat-conducting effect, to reduce costs and a weight of the thermally conductive packaging material, in other words, to reduce manufacturing costs and a weight of the inductor.

In an implementation, the inductor winding includes a magnetic core and an inductor coil wound around the magnetic core, and a gap between the inductor coil and the heat dissipation wall is filled with at least a part of the first packaging layer. A part that generates heat and that is of the inductor is mainly the inductor coil of the inductor winding. Therefore, the first packaging layer with relatively high heat dissipation efficiency is disposed between the inductor coil and the heat dissipation wall, so that the heat generated by the inductor winding can be directly transmitted to the heat dissipation wall through the first packaging layer with relatively high heat dissipation efficiency, to ensure that the inductor has relatively high heat dissipation efficiency.

According to the present invention, the inductor winding includes a magnetic core and an inductor coil, the magnetic core includes a winding region, the inductor coil is wound around the winding region of the magnetic core, the first packaging layer includes a first packaging region and a second packaging region, the first packaging region is located between the inductor coil and the heat dissipation wall, the second packaging region is located between the winding region and the heat dissipation wall, and a coefficient of thermal conductivity of the first packaging region is greater than a coefficient of thermal conductivity of the second packaging region. Usually, a region in which the inductor winding generates heat is a position of the inductor coil, and usually no heat is generated at a position of the magnetic core. A thermally conductive packaging material whose coefficient of thermal conductivity is greater than that of the second packaging region corresponding to the position of the magnetic core is used for the first packaging region corresponding to the position of the inductor coil, so that the manufacturing costs and the weight of the inductor can be further reduced when it is met that the inductor has relatively good heat-conducting effect.

In an implementation, the first packaging region includes a first packaging sub-region and a second packaging sub-region, the inductor coil includes a first part and a second part, the first part is closer to the winding region than the second part, the first packaging sub-region is located between the first part and the heat dissipation wall, the second packaging sub-region is located between the second part and the heat dissipation wall, and a coefficient of thermal conductivity of the first packaging sub-region is greater than a coefficient of thermal conductivity of the second packaging sub-region. Usually, it is more difficult to dissipate heat of the first part that is of the inductor coil and that is close to the winding region of the magnetic core than that of the second part far away from the winding region of the magnetic core. In this implementation, a thermally conductive packaging material whose coefficient of thermal conductivity is greater than that of the second packaging sub-region located between the second part and the heat dissipation wall is used for the first packaging sub-region located between the first part and the heat dissipation wall, so that the manufacturing costs and the weight of the inductor can be further reduced when it is met that the inductor has relatively good heat-conducting effect.

In an implementation, a heat dissipation structure is disposed on the heat dissipation wall, and the heat dissipation structure is configured to dissipate heat, so that the heat dissipation wall has better heat dissipation effect than the packaging wall. Alternatively, a heat dissipation coefficient of the heat dissipation wall is greater than a heat dissipation coefficient of the packaging wall, so that the heat dissipation wall has better heat dissipation effect than the packaging wall.

In an implementation, the heat dissipation structure includes a plurality of heat dissipation fins disposed at intervals, and the plurality of heat dissipation fins are protruded on the heat dissipation wall. The heat dissipation fins are disposed on the heat dissipation wall, so that the heat dissipation wall can be improved, to improve heat dissipation efficiency.

In an implementation, the heat dissipation wall includes an inner surface facing the inside of the housing and an outer surface facing away from the inside of the housing, and the heat dissipation fins are protruded on the inner surface and/or the outer surface. The heat dissipation fins are protruded on the inner surface, so that a contact area between the heat dissipation wall and the thermally conductive packaging material can be increased, to improve efficiency of transmitting, to the heat dissipation wall, heat transmitted in the thermally conductive packaging material. The heat dissipation fins are protruded on the outer surface, so that a contact area for heat exchange between the heat dissipation wall and the outside can be increased, to improve heat dissipation efficiency of the heat dissipation wall, so as to improve heat dissipation efficiency of the inductor.

In an implementation, the heat dissipation structure includes an air cooling pipe, and the air cooling pipe is disposed on the heat dissipation wall, and is located on a side that is of the heat dissipation wall and that is far away from the inside of the housing. The air cooling pipe is disposed, so that efficiency of heat exchange between the heat dissipation wall and the outside can be improved, to improve the heat dissipation efficiency of the inductor.

The air cooling pipe includes an air intake vent and an air exhaust vent that are disposed opposite to each other, and a fan is disposed at the air intake vent, to increase a flow speed of cooling gas in the air cooling pipe and improve heat dissipation effect of the air cooling pipe.

In an implementation, the thermal conductive packing material includes one or more of thermally conductive silica gel, thermally conductive silicone grease, thermally conductive quartz sand, or a mixed thermally conductive material.

In an implementation, the housing is a metal housing, so that the housing can have relatively good heat dissipation effect. In an implementation, the metal housing can further shield external electromagnetic interference, so that the inductor has a better working environment. In an implementation, the housing is a metal aluminum housing.

In an implementation, the inductor coil is formed by winding a flat copper wire. When there is same efficiency of the inductor, there is a same size for the copper wire of the inductor coil. In comparison with a case in which a round copper wire is used, there is higher winding efficiency and a simpler manufacturing manner when the flat copper wire is used. In addition, the flat copper wire of the same size generates a smaller amount of heat than the copper wire, and therefore there is a reduction in heat generated by the inductor.

According to a second aspect, this application further provides an electronic device. The electronic device includes the foregoing inductor. The inductor has good heat dissipation effect, and therefore use of the electronic device including the inductor is not affected due to a heat dissipation problem of the inductor. In addition, the inductor in this application has relatively low manufacturing costs and a relatively light weight, and therefore the electronic device including the inductor has relatively low manufacturing costs and a lighter weight.

The implementations of this application are described below in detail with reference to the accompanying drawings in the implementations of this application.

This application provides an inductor. As a component commonly used in a circuit, the inductor can be used in devices such as an inverter and a transformer, and is configured to: convert electric energy into magnetic energy, store the magnetic energy, release the magnetic energy in an appropriate case, and convert the magnetic energy into electric energy, in other words, implement a function of electromagnetic conversion, implement a function of allowing a direct current to pass through and blocking an alternating current, or implement a function of avoiding an abrupt change in a current flowing through the inductor.

<FIG> is a cross-sectional schematic diagram of an inductor <NUM> not forming part of the present invention. In this implementation, the inductor <NUM> includes an inductor winding <NUM>, a housing <NUM>, and a thermally conductive packaging material <NUM>. The inductor winding <NUM> is disposed in the housing <NUM>, and the thermally conductive packaging material <NUM> is potted in the housing <NUM> to fill a gap between the inductor winding <NUM> and the housing <NUM>. Specifically, when the inductor <NUM> is manufactured, the inductor winding <NUM> is first disposed in the housing <NUM>, and then the thermally conductive packaging material <NUM> is potted in the housing <NUM>, so that the thermally conductive packaging material <NUM> fills the gap between the inductor winding <NUM> and the housing <NUM> and a gap in the inductor winding <NUM>. The thermally conductive packaging material <NUM> is thermally conductive, and can transmit heat generated by the inductor winding <NUM> to each surface of the housing <NUM>. After being transmitted to each surface of the housing <NUM>, the heat is dissipated through the surface of the housing <NUM>. Heat on each surface of the housing <NUM> may be dissipated in various cooling manners such as air cooling and water cooling, to implement heat dissipation for the inductor <NUM>. Heat of the inductor <NUM> is transmitted to the housing <NUM>, and then heat exchange is performed with the outside through the housing <NUM>, to implement heat dissipation for the inductor <NUM>. In this application, the thermally conductive packaging material <NUM> may be one or more of thermally conductive silica gel, thermally conductive silicone grease, thermally conductive quartz sand, or another type of thermally conductive material. Preferably, the thermally conductive packaging material <NUM> is thermally conductive silica gel, and the thermally conductive silica gel may solidify after being potted in the housing <NUM>, to maintain stable positioning of the inductor winding <NUM> in the housing <NUM>.

In this implementation, the thermally conductive packaging material <NUM> is potted in the housing <NUM> under a vacuum condition, or the thermally conductive packaging material <NUM> is potted in the housing <NUM> and then vacuum pumping is performed in the housing <NUM>. In this way, air bubbles that may be generated when the thermally conductive packaging material <NUM> is potted in the housing <NUM> can be reduced or eliminated, to prevent the air bubbles from affecting heat-conducting effect of the thermally conductive packaging material <NUM>.

<FIG> is a schematic diagram of a principle of the inductor winding <NUM>. The inductor winding <NUM> is a main heat generation component in the inductor <NUM>. The inductor <NUM> includes a magnetic core <NUM> and an inductor coil <NUM>. The magnetic core <NUM> includes a winding region, and the inductor coil <NUM> is wound around the winding region of the magnetic core <NUM>. In this implementation, the magnetic core <NUM> includes a first part <NUM> and a second part <NUM> that are disposed opposite to each other, and a third part <NUM> and a fourth part <NUM> that are connected between the first part <NUM> and the second part <NUM>, and the third part <NUM> and the fourth part <NUM> are disposed opposite to each other. The coil is wound around the third part <NUM> and the fourth part <NUM>. In other words, the third part <NUM> and the fourth part <NUM> of the magnetic core <NUM> in this implementation are winding regions. The coil on the magnetic core <NUM> is formed by winding a metal wire, and is used to transmit a current. In this implementation, the coil is obtained by winding a metal copper wire. When a direct current passes through the inductor coil <NUM>, only a fixed magnetic line of force is present around the inductor coil <NUM>, which does not change with time. However, when an alternating current passes through the inductor coil <NUM>, the inductor coil <NUM> generates inductance to avoid a current change in an alternating current circuit. The magnetic core <NUM> is made of a magnetic material such as a magnetic powder core or a ferrite, and can bind a magnetic field more closely around an inductor element, to increase the inductance generated by the inductor coil <NUM>. In this implementation, coils wound around the third part <NUM> and the fourth part <NUM> are head-to-tail connected, and the current can be transmitted through the coil wound around the third part <NUM> to the coil wound around the fourth part <NUM>. In addition, a winding direction of the coil wound around the third part <NUM> is opposite to a winding direction of the coil wound around the fourth part <NUM>, in other words, a flow direction of the current on the coil wound around the third part <NUM> is opposite to a flow direction of the current on the coil wound around the fourth part <NUM> (as shown by arrows on the coils in the figure), so that magnetic fluxes generated by the two coils can be added, to increase inductance of the inductor <NUM>. A direction of a magnetic flux generated by the inductor <NUM> is shown by an arrow located on the magnetic core <NUM> in the figure.

A cross section of the metal wire wound to form the inductor coil <NUM> may be in various shapes, for example, may be a thin round metal wire or a flat metal wire. <FIG> is a schematic diagram of a structure of the inductor winding <NUM> according to an implementation of this application. In this implementation, the inductor coil <NUM> is formed by winding a flat copper wire. When there is same efficiency of the inductor <NUM>, there is a same size for the copper wire of the inductor coil <NUM>. In comparison with a case in which a round copper wire is used, there is higher winding efficiency and a simpler manufacturing manner when the flat copper wire is used. In addition, the flat copper wire of the same size generates a smaller amount of heat than the copper wire, and therefore there is a reduction in heat generated by the inductor <NUM>.

Referring to <FIG> again, in an implementation, the housing <NUM> is made of a metal material. The metal material has a relatively good heat-conducting property and relatively high strength, can quickly dissipate heat, and can further achieve relatively good protection effect for the inductor winding <NUM> disposed in the metal material. In an implementation, the metal housing <NUM> further has an electromagnetic shielding function, and can shield external electromagnetic interference, so that the inductor <NUM> has a better working environment. In this implementation, the housing <NUM> is a metal aluminum housing. Metal aluminum has a relatively large coefficient of thermal conductivity, can quickly conduct heat, and therefore can effectively dissipate heat generated by the inductor <NUM>.

The housing <NUM> includes a heat dissipation wall <NUM> and a packaging wall <NUM>. The heat dissipation wall <NUM> and the packaging wall <NUM> form an accommodation cavity. Both the inductor winding <NUM> and the thermally conductive packaging material <NUM> are accommodated in the accommodation cavity of the housing <NUM>. Specifically, in this implementation, the housing <NUM> is a cubic housing, and includes one heat dissipation wall <NUM> and five packaging walls <NUM>. The heat dissipation wall <NUM> forms a bottom support of the inductor <NUM>, and the heat dissipation wall <NUM> and the packaging walls <NUM> are connected to form a cubic housing. It may be understood that in another implementation of this application, there may be a plurality of heat dissipation walls <NUM>, in other words, there may be two or more heat dissipation walls <NUM>. Alternatively, in an implementation, the housing <NUM> may be a housing in various other shapes such as a cylindrical shape and a prismatic shape.

The heat dissipation wall <NUM> has better heat dissipation effect than the packaging wall <NUM>, and a larger amount of heat is dissipated through the heat dissipation wall <NUM> than through the packaging wall <NUM>. In an implementation, most of heat dissipated by the inductor <NUM> is dissipated through the heat dissipation wall <NUM>. In this implementation of this application, a heat dissipation structure is disposed on the heat dissipation wall <NUM>, so that heat on the heat dissipation wall <NUM> can be dissipated as quickly as possible, and a larger amount of heat can be dissipated through the heat dissipation wall <NUM> than through the packaging wall <NUM>. In this implementation, the heat dissipation structure is a plurality of heat dissipation fins <NUM> that are disposed at intervals and that are protruded on the heat dissipation wall <NUM>. The heat dissipation fins <NUM> are disposed on the heat dissipation wall <NUM>, so that a contact area for heat exchange between the heat dissipation wall <NUM> and the outside can be increased, to improve heat dissipation efficiency. Specifically, the heat dissipation wall <NUM> includes an inner surface <NUM> facing the inside of the housing <NUM> and an outer surface <NUM> facing away from the inside of the housing <NUM>. The heat dissipation fins <NUM> are protruded on the inner surface <NUM> and/or the outer surface <NUM>, in other words, the heat dissipation fins <NUM> may be protruded on the inner surface <NUM> or the outer surface <NUM>, or the heat dissipation fins <NUM> are protruded on both the inner surface <NUM> and the outer surface <NUM>. In this implementation, the heat dissipation fins <NUM> are protruded on the outer surface <NUM>, so that a contact area for heat exchange between the heat dissipation wall <NUM> and the outside can be increased, to improve heat dissipation efficiency of the housing <NUM>, so as to improve heat dissipation efficiency of the inductor <NUM>. <FIG> is a cross-sectional schematic diagram of an inductor <NUM> not forming part of the present invention. In this implementation, the heat dissipation fins <NUM> are protruded on both the inner surface <NUM> and the outer surface <NUM> of the heat dissipation wall <NUM>. The heat dissipation fins <NUM> are protruded on the inner surface <NUM>, so that a contact area between the heat dissipation wall <NUM> and the thermally conductive packaging material <NUM> can be increased, to improve efficiency of transmitting heat transmitted in the thermally conductive packaging material <NUM> to the heat dissipation wall <NUM>. The heat dissipation fins <NUM> are protruded on the outer surface <NUM>, so that a contact area for heat exchange between the heat dissipation wall <NUM> and the outside is increased, to improve heat dissipation efficiency of the heat dissipation wall <NUM>, so as to improve heat dissipation efficiency of the inductor <NUM>. Therefore, in this implementation, the heat dissipation fins <NUM> can quickly transmit and dissipate the heat generated by the inductor winding <NUM>, to improve the heat dissipation efficiency of the inductor <NUM>.

It may be understood that in an implementation, either or each of the inner surface <NUM> and the outer surface <NUM> of the heat dissipation wall <NUM> may be an uneven surface, for example, a sawtooth surface or a wavy surface. The inner surface <NUM> of the heat dissipation wall <NUM> is an uneven surface, so that the contact area between the heat dissipation wall <NUM> and the thermally conductive packaging material <NUM> can be increased, and the heat transmitted in the thermally conductive packaging material <NUM> is quickly transmitted to the heat dissipation wall <NUM>. The outer surface <NUM> of the heat dissipation wall <NUM> is an uneven surface, so that the contact area for heat exchange between the heat dissipation wall <NUM> and the outside can be increased, to ensure that heat transmitted to the heat dissipation wall <NUM> is quickly dissipated.

In another implementation of this application, the heat dissipation wall <NUM> of the housing <NUM> may be made of a material whose heat dissipation coefficient is greater than that of the packaging wall <NUM>, so that the heat dissipation wall <NUM> has better heat dissipation effect than the packaging wall <NUM>, and a larger amount of heat is dissipated through the heat dissipation wall <NUM> than through the packaging wall <NUM>.

<FIG> is a cross-sectional schematic diagram of an inductor <NUM> not forming part of the present invention. A difference between the inductor <NUM> in this implementation and the inductor <NUM> shown in <FIG> lies in that the heat dissipation structure further includes an air cooling pipe <NUM>, and the air cooling pipe <NUM> is disposed on the outer surface <NUM> of the heat dissipation wall <NUM>. In an optional implementation, the air cooling pipe <NUM> is disposed as a tubular structure, and includes an air intake vent <NUM> and an air exhaust vent <NUM> that are disposed opposite to each other. Cooling air enters through the air intake vent <NUM>, flows through the air cooling pipe <NUM>, performs heat exchange with the heat dissipation wall <NUM>, and then exits through the air exhaust vent <NUM>. In an implementation, a fan <NUM> is disposed at the air intake vent <NUM>, to improve flow efficiency of air in the air cooling pipe <NUM>, so that efficiency of performing heat exchange between the air in the air cooling pipe <NUM> and the heat dissipation wall <NUM> is improved, to improve the heat dissipation efficiency of the inductor <NUM>. In an implementation, a negative pressure fan is disposed at the air exhaust vent <NUM>, and is configured to quickly draw out the air in the air cooling pipe <NUM>, to further promote flow of the air in the air cooling pipe <NUM>. In this implementation, the heat dissipation fins <NUM> protruded on the heat dissipation wall <NUM> are located in the air cooling pipe <NUM>. The heat dissipation fins <NUM> are used to increase a contact area between the heat dissipation wall <NUM> and the air in the air cooling pipe <NUM>, to improve the heat dissipation efficiency of the inductor <NUM>. There is a gap between the heat dissipation fins <NUM> and an inner wall of the air cooling pipe <NUM>. Alternatively, in an implementation, a hole is disposed on the heat dissipation fin <NUM>, to ensure that the air in the air cooling pipe <NUM> can flow more quickly. It may be understood that in another implementation of this application, the heat dissipation structure may include only the air cooling pipe <NUM> but no heat dissipation fins <NUM>. Alternatively, in an implementation, the air cooling pipe <NUM> may be replaced with a water cooling pipe. The water cooling pipe includes a water inlet and a water outlet that are disposed to each other. Cooling liquid flows in from the water inlet of the water cooling pipe, flows through the water cooling pipe, performs heat exchange with the heat dissipation wall <NUM>, and then flows out from the water outlet, to improve the heat dissipation efficiency of the heat dissipation wall <NUM>.

Referring to <FIG> again, in this implementation, the thermally conductive packaging material <NUM> includes a first packaging layer <NUM> and a second packaging layer <NUM>. A coefficient of thermal conductivity of the first packaging layer <NUM> is greater than a coefficient of thermal conductivity of the second packaging layer <NUM>. The first packaging layer <NUM> is closer to the heat dissipation wall <NUM> than the second packaging layer <NUM>. Usually, a larger heat dissipation coefficient of the thermally conductive packaging material <NUM> indicates higher costs of the thermally conductive packaging material <NUM> and a heavier weight. For example, thermally conductive silica gel is a type of silica gel formed after a specific conductive filler is added based on silicone rubber. For the thermally conductive packaging material <NUM> of a thermally conductive silica gel type, a conductive filler added to common thermally conductive silica gel is aluminum trioxide or the like, and a conductive filler added to highly thermally conductive silica gel is a thermally conductive material such as boron nitride. The highly thermally conductive silica gel has higher manufacturing costs than the common thermally conductive silica gel, and has a heavier weight than the common thermally conductive silica gel. In this application, the housing <NUM> includes the heat dissipation wall <NUM> and the packaging wall <NUM>, and the heat dissipation wall <NUM> has better heat dissipation effect than the packaging wall <NUM>. Therefore, most of heat generated by the inductor winding <NUM> is dissipated through the heat dissipation wall <NUM>, and less heat is dissipated through the packaging wall <NUM>. A material whose coefficient of thermal conductivity is greater than that of the second packaging layer <NUM> is used for the first packaging layer <NUM> close to the heat dissipation wall <NUM> with a relatively large heat dissipation coefficient, so that it can be ensured that most of the heat generated by the inductor winding <NUM> can be quickly transmitted to the housing through the first packaging layer <NUM> with good heat-conducting effect, to ensure relatively good heat dissipation for the inductor <NUM>. In addition, a part of a region that is in the housing <NUM> and that is far away from the heat dissipation wall <NUM> is filled with the second packaging layer <NUM> with relatively poor heat-conducting effect, to reduce costs and a weight of the thermally conductive packaging material <NUM>, in other words, to reduce manufacturing costs and a weight of the inductor <NUM>. It may be understood that in another implementation of this application, the thermally conductive packaging material <NUM> may further include more packaging layers, for example, may further include a third packaging layer and a fourth packaging layer. Different packaging layers may have different coefficients of thermal conductivity, so that the costs and the weight of the thermally conductive packaging material <NUM> are reduced when it is met that the inductor <NUM> has relatively good heat-conducting effect.

In an implementation, a gap between the inductor coil <NUM> and the heat dissipation wall <NUM> is filled with at least a part of the first packaging layer <NUM>. The gap between the inductor coil <NUM> and the heat dissipation wall <NUM> refers to space between a surface that is of the inductor coil <NUM> and that is closest to the heat dissipation wall <NUM> and the heat dissipation wall <NUM>. A part that generates heat and that is of the inductor <NUM> is mainly the inductor coil <NUM> of the inductor winding <NUM>. Therefore, the first packaging layer <NUM> is disposed between the inductor coil <NUM> and the heat dissipation wall <NUM>, so that the heat generated by the inductor winding <NUM> can be directly transmitted to the heat dissipation wall <NUM> through the first packaging layer <NUM>. The first packaging layer <NUM> has relatively high heat dissipation efficiency, and therefore the heat generated by the inductor winding <NUM> can be efficiently transmitted to the housing <NUM>, to ensure that the inductor <NUM> can have relatively high heat dissipation efficiency.

In the inductor <NUM> in an implementation, the coil <NUM> of the inductor winding <NUM> is a structure that mainly generates heat, and the magnetic core <NUM> generates less heat. Therefore, a thermally conductive packaging material at a corresponding position of the coil <NUM> may have a larger coefficient of thermal conductivity than a thermally conductive packaging material at a corresponding position of the magnetic core <NUM>, so that the manufacturing costs of the inductor <NUM> and the weight of the inductor <NUM> are further reduced when the heat generated by the inductor winding <NUM> is dissipated as quickly as possible. <FIG> is a cross-sectional schematic diagram of an inductor <NUM> according to an embodiment of the present invention. A difference between this implementation and the implementation shown in <FIG> lies in that the first packaging layer <NUM> includes a first packaging region <NUM> and a second packaging region <NUM>. The first packaging region <NUM> is located between the inductor coil <NUM> and the heat dissipation wall <NUM>. The second packaging region <NUM> is located between the winding region of the magnetic core <NUM> and the heat dissipation wall <NUM>. In other words, an orthographic projection of the first packaging region <NUM> on the heat dissipation wall <NUM> covers an orthographic projection of the inductor coil <NUM> on the heat dissipation wall <NUM>, and an orthographic projection of the second packaging region <NUM> on the heat dissipation wall <NUM> covers an orthographic projection of the winding region of the magnetic core <NUM> on the heat dissipation wall <NUM>. In this implementation, a coefficient of thermal conductivity of the first packaging region <NUM> is greater than a coefficient of thermal conductivity of the second packaging region <NUM>, in other words, a thermally conductive packaging material <NUM> whose coefficient of thermal conductivity is less than that of a thermally conductive packaging material <NUM> of the first packaging region <NUM> is used for the second packaging region <NUM>. In this implementation, a thermally conductive packaging material <NUM> whose coefficient of thermal conductivity is greater than that of the second packaging region <NUM> corresponding to the position of the magnetic core <NUM> is used for the first packaging region <NUM> corresponding to the position of the inductor coil <NUM>, in other words, different thermally conductive packaging materials <NUM> are correspondingly used for different corresponding positions of the inductor winding <NUM>, so that the manufacturing costs and the weight of the inductor <NUM> can be further reduced when it is met that the inductor <NUM> has relatively good heat-conducting effect.

It may be understood that in the inductor <NUM> in another implementation of this application not forming part of the present invention, the magnetic core <NUM> of the inductor winding <NUM> generates more heat than the coil <NUM>. In this implementation, the coefficient of thermal conductivity of the thermally conductive packaging material at the corresponding position of the coil <NUM> is less than the coefficient of thermal conductivity of the thermally conductive packaging material at the corresponding position of the magnetic core <NUM>, so that the manufacturing costs of the inductor <NUM> and the weight of the inductor <NUM> can be further reduced when the heat generated by the inductor winding <NUM> is dissipated as quickly as possible.

<FIG> is a schematic diagram of a structure of an inductor <NUM> according to another embodiment of the present invention. A difference between this implementation and the implementation shown in <FIG> lies in that the first packaging region <NUM> includes a first packaging sub-region <NUM> and a second packaging sub-region <NUM>. A coefficient of thermal conductivity of the first packaging sub-region <NUM> is greater than a coefficient of thermal conductivity of the second packaging sub-region <NUM>, in other words, a coefficient of thermal conductivity of a thermally conductive packaging material <NUM> used for the second packaging sub-region <NUM> is less than a coefficient of thermal conductivity of a thermally conductive packaging material <NUM> used for the first packaging sub-region <NUM>. The inductor coil <NUM> includes a first part <NUM> and a second part <NUM>, and the first part <NUM> is closer to the winding region of the magnetic core <NUM> than the second part <NUM>. It should be noted that the first part <NUM> and the second part <NUM> are two parts that are obtained through division for ease of description, but are not two structures that actually exist. The first packaging sub-region <NUM> is located between the first part <NUM> and the heat dissipation wall <NUM>, and the second packaging sub-region <NUM> is located between the second part <NUM> and the heat dissipation wall <NUM>. Usually, it is more difficult to dissipate heat of the first part <NUM> that is of the inductor coil <NUM> and that is close to the winding region of the magnetic core <NUM> than that of the second part <NUM> far away from the winding region of the magnetic core <NUM>. In this implementation, a thermally conductive packaging material whose coefficient of thermal conductivity is greater than that of the second packaging sub-region <NUM> located between the second part <NUM> and the heat dissipation wall <NUM> is used for the first packaging sub-region <NUM> located between the first part <NUM> and the heat dissipation wall <NUM>. In this way, when heat at all positions of the inductor coil <NUM> can be relatively quickly dissipated, a same thermally conductive packaging material <NUM> with a large coefficient of thermal conductivity does not need to be used at all the positions, so that the manufacturing costs and the weight of the inductor <NUM> can be further reduced when it is met that the inductor <NUM> has relatively good heat-conducting effect.

In this application, thermally conductive packaging materials <NUM> with different coefficients of thermal conductivity are potted at different positions in the housing <NUM>, so that the heat generated by the inductor winding <NUM> in the housing <NUM> can be quickly transmitted to the housing <NUM>, to ensure that when the inductor <NUM> can efficiently dissipate heat, the costs and the weight of the thermally conductive packaging material <NUM> are reduced, and the manufacturing costs and the weight of the inductor <NUM> are reduced.

This application further provides an electronic device. The electronic device includes said inductor <NUM>. Specifically, the electronic device may be an electronic device such as an inverter or a transformer. The inductor has good heat dissipation effect, and therefore use of the electronic device including the inductor is not affected due to a heat dissipation problem of the inductor. In addition, the inductor in this application has relatively low manufacturing costs and a relatively light weight, and therefore the electronic device including the inductor has relatively low manufacturing costs and a lighter weight.

Claim 1:
An inductor (<NUM>), comprising an inductor winding (<NUM>), a housing (<NUM>), and a thermally conductive packaging material (<NUM>), wherein the inductor winding (<NUM>) is disposed in the housing (<NUM>); the thermally conductive packaging material (<NUM>) is potted in the housing (<NUM>) to fill a gap between the inductor winding (<NUM>) and the housing (<NUM>); the thermally conductive packaging material (<NUM>) comprises a first packaging layer (<NUM>) and a second packaging layer (<NUM>), and a coefficient of thermal conductivity of the first packaging layer (<NUM>) is greater than a coefficient of thermal conductivity of the second packaging layer (<NUM>); and the housing (<NUM>) comprises a heat dissipation wall (<NUM>) and a packaging wall (<NUM>), and the first packaging layer (<NUM>) is closer to the heat dissipation wall (<NUM>) than the second packaging layer (<NUM>), wherein the inductor winding (<NUM>) comprises a magnetic core (<NUM>) and an inductor coil (<NUM>), the magnetic core (<NUM>) comprises a winding region, the inductor coil (<NUM>) is wound around the winding region of the magnetic core (<NUM>),
characterised in that the heat dissipation wall (<NUM>) has a better heat dissipation effect than the packaging wall (<NUM>),
the first packaging layer (<NUM>) includes a first packaging region (<NUM>) and a second packaging region (<NUM>), the first packaging region (<NUM>) is located between the inductor coil (<NUM>) and the heat dissipation wall (<NUM>), the second packaging region (<NUM>) is located between the winding region and the heat dissipation wall (<NUM>), and a coefficient of thermal conductivity of the first packaging region (<NUM>) is greater than a coefficient of thermal conductivity of the second packaging region (<NUM>).