Patent Description:
Embodiments of this application relate to the field of terminal technologies, and in particular, to a vapor chamber and an electronic device.

With the continuous improvement of electronic integration technologies, electronic devices are developing in the direction of miniaturization, lightening, and thinning, and the integration degree of electronic components in the electronic devices is increasingly high. In this way, the power consumption of electronic components is increasing, more heat is generated, and the heat is concentrated and difficult to be dissipated. Excessive heat will cause the temperatures of the electronic devices to rise, thereby affecting the performance and the life of the electronic devices.

To resolve the heat dissipation problem of the electronic device, a heat pipe (Heat Pipe, HP) is usually arranged in a middle frame of the electronic device, and a cavity for containing liquid media such as water or liquid ammonia is defined inside the heat pipe. The liquid medium transfers the heat generated by the electronic device from one end of the heat pipe to an other end of the heat pipe and releases the heat by its own phase change, so that the temperature of the electronic device can be reduced.

However, because the cavity for storing the liquid medium is provided inside the heat pipe, limited by this structure, the thickness value of the heat pipe is relatively large, which is not conducive to realization of a light and thin electronic device.

<CIT> discloses a thermal management system.

Embodiments of this application provide a heat equalizing plate (also referred to as "vapor chamber" in the present document) in an electronic device, which can resolve the problem in the related art that it is difficult to realize a light and thin electronic device due to a relatively great thickness of a heat pipe for heat dissipation.

A first aspect of the embodiments of this application provides a vapor chamber applied to an electronic device, including: a plurality of graphite sheets made of a graphite material or a graphene material, where the plurality of graphite sheets are arranged in a stacked manner, and a connection layer is arranged between two adjacent graphite sheets.

The vapor chamber provided in the embodiments of this application is formed by arranging a plurality of graphite sheets in a stacked manner, and a thermal conductivity coefficient of the material of the vapor chamber is high, so that the vapor chamber has a good heat conduction performance; because there is no need to define a cavity inside the vapor chamber, the vapor chamber can have a relatively small thickness value; and under the premise that the heat dissipation performance of the vapor chamber is basically the same as the heat dissipation performance of a heat pipe, the thickness of the vapor chamber can be less than the thickness of the heat pipe. In this way, when a vapor chamber is used to replace a heat pipe to assist an electronic component of an electronic device in dissipating heat, the thickness of the electronic device can also be correspondingly reduced, thereby facilitating the realization of a light and thin electronic device.

In a possible implementation, the connection layer is an adhesive layer, where two adjacent graphite sheets are bonded by the adhesive layer; or when a quantity of graphite sheets is greater than two, a plurality of connection layers are arranged, some of the plurality of connection layers are adhesive layers, and the remaining of the plurality of connection layers are metal bonding layers.

In a possible implementation, the adhesive layer is a double-sided adhesive layer made of a double-sided adhesive material; or the adhesive layer is a thermally conductive gel layer made of thermally conductive gel.

Thicknesses of at least two of the plurality of graphite sheets are different.

A thickness of each part of the vapor chamber is the same.

The vapor chamber includes at least two graphite sheets with uneven thicknesses, and the at least two graphite sheets with uneven thicknesses are adjacent to each other.

The vapor chamber includes at least one graphite sheet with an uneven thickness.

In a possible implementation, the plurality of graphite sheets includes at least a first graphite sheet and a second graphite sheet, both the first graphite sheet and the second graphite sheet are outermost layers of the vapor chamber in a stacked arrangement direction, a surface of the first graphite sheet facing away from the second graphite sheet is provided with bonding glue, and a surface of the second graphite sheet facing away from the first graphite sheet is provided with a polyethylene terephthalate PET film.

An example provides an electronic device, including: a middle frame, a display screen, a circuit board, a heating element, a heat conduction element, and the vapor chamber provided in this application, where the display screen and the circuit board are respectively arranged on two sides of the middle frame in a thickness direction of the electronic device, the heating element is arranged on the circuit board, the heating element is in contact with the middle frame through the heat conduction element, the middle frame is provided with a groove, and the vapor chamber is mounted in the groove.

A thickness of the vapor chamber is not greater than a depth of the groove; and an orthographic projection of the heat conduction element on the display screen is located within an orthographic projection of the vapor chamber on the display screen.

There are a plurality of heating elements, and a shape of the vapor chamber is adapted to a shape constructed by the plurality of heating elements.

The vapor chamber includes a rectangular plate body and a heat conduction plate body, and the heating elements all exactly face the heat conduction plate body; in a width direction of the electronic device, a minimum value of distances between first side edges of all the heating elements and a same side edge of the heat conduction plate body is a first distance, and a minimum value of distances between second side edges of all the heating elements and a same side edge of the heat conduction plate body is a second distance; in a direction of the electronic device, a minimum value of distances between third side edges of all the heating elements and a same side edge of the heat conduction plate body is a third distance, and a minimum value of distances between fourth side edges of all the heating elements and a same side edge of the heat conduction plate body is a fourth distance; and the first distance, the second distance, the third distance, and the fourth distance are all positive numbers.

The first distance is equal to the second distance, and the third distance is equal to the fourth distance.

The electronic device further includes a battery, where the battery is located on a side of the middle frame facing away from the display screen, the battery and the circuit board are spaced apart in a length direction of the middle frame, and a part of the battery is opposite to a part of the vapor chamber.

The electronic device further includes a first heat dissipation portion, where the first heat dissipation portion is located between the display screen and the vapor chamber, and the orthographic projection of the vapor chamber on the display screen is located within an orthographic projection of the first heat dissipation portion on the display screen.

The electronic device further includes a second heat dissipation portion mounted on the middle frame, where the second heat dissipation portion is located between the middle frame and the display screen, and the second heat dissipation portion and the first heat dissipation portion are spaced apart in the length direction of the middle frame.

The electronic device further includes a rear cover and a third heat dissipation portion, where the rear cover is arranged on a side of the circuit board facing away from the middle frame, and the third heat dissipation portion is arranged between the circuit board and the rear cover.

The first heat dissipation portion, the second heat dissipation portion, and the third heat dissipation portion are any one of graphite sheets, copper foil, aluminum foil, vapor chambers, or heat pipes.

The electronic device provided in the embodiments of this application includes a vapor chamber. The vapor chamber is formed by arranging a plurality of graphite sheets in a stacked manner, and a thermal conductivity coefficient of the material of the vapor chamber is high, so that the vapor chamber has a good heat conduction performance; because there is no need to define a cavity inside the vapor chamber, the vapor chamber can have a relatively small thickness value; and under the premise that the heat dissipation performance of the vapor chamber is basically the same as the heat dissipation performance of a heat pipe, the thickness of the vapor chamber can be less than the thickness of the heat pipe. In this way, when a vapor chamber is used to replace a heat pipe to assist an electronic component of an electronic device in dissipating heat, the thickness of the electronic device can also be correspondingly reduced, thereby facilitating the realization of a light and thin electronic device.

Furthermore, there may be provided an electronic device, including: a middle frame, a display screen, a circuit board, a heating element, a heat conduction element, and the vapor chamber provided in the first aspect of the embodiments of this application, where the display screen and the circuit board are respectively arranged on two sides of the middle frame in a thickness direction of the electronic device, the heating element is arranged on the circuit board, the vapor chamber is arranged between the middle frame and the circuit board, and the heating element is in contact with the vapor chamber through the heat conduction element.

To improve the performance of an electronic device 100a, an increasing number of electronic components 61a with high power consumption are integrated on the electronic device 100a. These electronic components 61a will generate a lot of heat during working, and the heat is concentrated in the electronic device 100a and difficult to be dissipated, causing the temperature of the electronic device 100a to rise. Therefore, how to overcome the temperature rise is a problem to be urgently resolved for the electronic device 100a.

Some examples in the related art provide a heat pipe 50a. As shown in <FIG>, the heat pipe 50a is arranged on a middle frame 20a of the electronic device 100a, and the heat pipe 50a has a cavity inside. The cavity is filled with a liquid medium such as water or liquid nitrogen. One end of the heat pipe 50a is an evaporation end, and an other end of the heat pipe 50a is a condensation end. The heat dissipation principle of the electronic device 100a with the heat pipe 50a is generally as follows: The heat generated by the electronic components 61a on the electronic device 100a is transferred to the evaporation end of the heat pipe 50a; the liquid medium inside the evaporation end of the heat pipe 50a absorbs the heat and then evaporates to form vapor; the vapor diffuses to the condensation end of the heat pipe 50a and releases heat; and the vapor that has released the heat re-condenses into a liquid when it is cooled and flows back to the evaporation end. The process is repeated, so that the heat generated by the electronic components 61a is dissipated to the environment in which the heat pipe 50a is located, thereby achieving cooling.

Another example in the related art provides a vapor chamber (Vapor Chamber, VC). The vapor chamber is arranged on the middle frame 20a of the electronic device 100a, and the vapor chamber is also provided with a cavity for containing liquid media such as water or liquid ammonia inside. The heat dissipation principle of the vapor chamber is similar to the heat dissipation principle of the heat pipe 50a, which will not be described herein again. The difference between the vapor chamber and the heat pipe 50a is that the liquid medium in the vapor chamber flows along a plane, and a heat conduction area of the vapor chamber is larger than a heat conduction area of the heat pipe 50a, so that the heat dissipation efficiency of the vapor chamber is higher.

It can be seen that each of the heat pipe 50a and the vapor chamber is provided with a cavity for a liquid medium to flow inside, and the heat transfer and heat dissipation are realized by a phase change of the liquid medium. However, both the thickness of the heat pipe 50a and the thickness the vapor chamber cannot be excessively small due to the cavity formed inside. For example, the minimum thickness of the heat pipe 50a can only reach <NUM> at present, and the minimum thickness of the vapor chamber can only reach <NUM> at present, which causes the electronic device 100a that mainly uses the heat pipe 50a or the vapor chamber to conduct the heat of the electronic components 61a to be difficult to be light and thin. In addition, the manufacturing processes of the heat pipe 50a and the vapor chamber are complex, and the manufacturing costs thereof are high, which further leads to a relatively high cost of the electronic device 100a having the heat pipe 50a and/or the vapor chamber. In addition, it can also be understood that both the heat pipe 50a and the vapor chamber need to be configured to have an evaporation end and a condensation end, the heat conduction path of the heat pipe 50a is linear, and the heat conduction path of the vapor chamber extends in one direction. Both the heat pipe 50a and the vapor chamber are difficult to be constructed in an arc shape or other irregular shapes, and consequently it is difficult for the heat pipe 50a to be adapted to heating elements arranged in various manners.

In view of the foregoing problem, the designer of this application attempted to design a vapor chamber to conduct heat of an electronic device. The vapor chamber is made of a material with a high thermal conductivity coefficient, and the vapor chamber has a large heat conduction area. In this way, the vapor chamber can have good heat dissipation performance. Subsequently, the designer of this application found that the graphite material has a high thermal conductivity coefficient, and then conceived of using a plurality of graphite sheets to construct the vapor chamber. In this way, when the heat dissipation performance of the vapor chamber can be kept equivalent to the heat dissipation performance of the heat pipe, the thickness of the vapor chamber can be less than the thickness of the heat pipe, so that the electronic device with a vapor chamber can be lighter and thinner.

The following describes implementations provided in the embodiments of this application in detail:.

An example provides an electronic device <NUM>. The electronic device <NUM> may include, but not limited to, a mobile phone, a tablet computer, a notebook computer, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a handheld computer, an interphone, a netbook, a POS machine, a personal digital assistant (personal digital assistant, PDA), a wearable device, a virtual reality device, or another mobile or fixed terminal with a battery <NUM>.

<FIG> is a cross-sectional view of an electronic device <NUM> taken in a direction of a reference line L-L in <FIG> according to this example. Referring to <FIG> and <FIG>, in this example, the electronic device <NUM> includes a display screen <NUM>, a middle frame <NUM>, a circuit board <NUM>, a heating element <NUM> and a heat conduction element, and the middle frame <NUM> can be used to carry the display screen <NUM> and the circuit board <NUM>. The display screen <NUM> and the circuit board <NUM> are respectively arranged on two sides of the middle frame <NUM> in a thickness direction of the electronic device <NUM>, the heating element <NUM> is arranged on the circuit board <NUM>, and the heating element <NUM> is in contact with the middle frame <NUM> through the heat conduction element. It should be noted that, in the accompanying drawings of the embodiments of this application, directions of an X-axis, a Y-axis, and a Z-axis respectively represent a width direction, a length direction, and a thickness direction of the electronic device <NUM>.

In <FIG>, the middle frame <NUM> may specifically include a middle plate <NUM> and a frame <NUM> connected to a circumferential edge of the middle plate <NUM>. The frame <NUM> protrudes toward a side at which the display screen <NUM> is located. The middle plate <NUM> and the frame <NUM> jointly form an accommodating space.

As an electronic component of the electronic device <NUM>, the heating element <NUM> may be one or more of a power amplifier, an application processor (Central Processing Unit, CPU), a power management chip (Power Management IC, PMIC), a universal flash storage (Universal Flash Storage, UFS), a charging chip, an external baseband, and an image processing chip (Image Signal Processor, ISP). The power amplifier herein may be a <NUM> PA and a <NUM> PA.

When the electronic device <NUM> has the foregoing several heating elements <NUM>, the electronic device <NUM> can realize more functions. In this case, a plurality of heating elements <NUM> are arranged. The plurality of heating elements <NUM> may all be arranged on a first surface of the circuit board <NUM>, or the plurality of heating elements <NUM> are respectively arranged on the first surface and a second surface of the circuit board <NUM> (for example, as shown in <FIG>). Herein, the first surface refers to a surface of the circuit board <NUM> facing the display screen <NUM>, and on the contrary, the second surface refers to a surface of the circuit board <NUM> facing away from the display screen <NUM>.

For example, the electronic device <NUM> may have three heating elements <NUM>: a CPU, a PMIC, and a <NUM> PA. In this case, the layout of the three heating elements <NUM> includes, but is not limited to, the following possible situations: In the first situation, the CPU, the PMIC, and the <NUM> PA are all arranged on the first surface of the circuit board <NUM>; in the second situation, the CPU and the PMIC are arranged on the first surface of the circuit board <NUM>, and the <NUM> PA is arranged on the second surface of the circuit board <NUM>; and in the third case, the CPU is arranged on the first surface of the circuit board <NUM>, and the PMIC and the <NUM> PA are arranged on the second surface of the circuit board <NUM>. It can be seen that, when a plurality of heating elements <NUM> are arranged, one or more heating elements <NUM> may be mounted on the first surface of the circuit board <NUM>.

Specifically, the electronic device <NUM> further includes a shielding cover <NUM>. The shielding cover <NUM> is connected to the circuit board <NUM>, and the shielding cover <NUM> and the circuit board <NUM> jointly form a shielding space. The heating element <NUM> is accommodated in the shielding space. In this way, the shielding cover <NUM> can prevent the heating element <NUM> from being interfered by an external electromagnetic field. If both the first surface and the second surface of the circuit board <NUM> are provided with heating elements <NUM>, correspondingly, both the first surface and the second surface of the circuit board <NUM> may be connected to a shielding cover <NUM>. It is to be noted that, the shielding cover <NUM> may be a heat conduction element. In this case, the heating element <NUM> transfers heat to the circuit board <NUM>, then the circuit board <NUM> conducts the heat to the shielding cover <NUM> connected to the circuit board <NUM>, and subsequently the shielding cover <NUM> transfers the heat to the middle frame <NUM>. The shielding cover <NUM> may be a metal shielding cover made of a metal material, and the metal shielding cover <NUM> has a strong heat conduction capability.

In some examples, as shown in <FIG>, the heat conduction element may further include thermally conductive gel <NUM>, and the heating element <NUM> transfers heat to the middle frame <NUM> through the thermally conductive gel <NUM>. Specifically, for a heating element <NUM> located on the first surface, the heating element <NUM> and the shielding cover <NUM> are connected by the thermally conductive gel <NUM>, and the shielding cover <NUM> and the middle frame <NUM> are connected by the thermally conductive gel <NUM>, and some heat generated by the heating element <NUM> can be conducted to the middle frame <NUM> through the thermally conductive gel <NUM>. In addition, when a plurality of heating elements <NUM> are arranged on the circuit board <NUM>, there is thermally conductive gel between each heating element and the shielding cover <NUM>.

The electronic device <NUM> further includes a vapor chamber <NUM>. The vapor chamber <NUM> is configured to assist the electronic device <NUM> in heat dissipation.

As shown in <FIG>, the vapor chamber <NUM> may be mainly formed by a plurality of graphite sheets <NUM>. The graphite sheets <NUM> may be made of a graphite material, or may be made of a graphene material. Both graphite and graphene have advantages such as low density and relatively high thermal conductivity, so that vapor chamber <NUM> has relatively good heat conduction performance. Specifically, the thermal conductivity coefficient of graphene is as high as <NUM> W/m*K.

The plurality of graphite sheets <NUM> in the vapor chamber <NUM> are arranged in a stacked manner in one direction, and two adjacent graphite sheets <NUM> are connected by a connection layer, so that the plurality of graphite sheets <NUM> form a whole. It may be understood that in the direction in which the graphite sheets <NUM> are arranged in a stacked manner, the plurality of graphite sheets <NUM> includes at least a first graphite sheet and a second graphite sheet. Both the first graphite sheet and the second graphite sheet are outermost layers of the vapor chamber <NUM>. In addition, when the vapor chamber <NUM> is mounted on the electronic device <NUM>, a surface of the first graphite sheet facing away from the second graphite sheet is in contact with the electronic device <NUM>.

For example, in <FIG>, when there are two graphite sheets <NUM>, the vapor chamber <NUM> includes a first graphite sheet and a second graphite sheet, and the first graphite sheet and the second graphite sheet are adjacent to each other. In this case, the vapor chamber <NUM> has only one connection layer.

In another example, as shown in <FIG>, when there are at least three graphite sheets <NUM>, the vapor chamber <NUM> includes a first graphite sheet, a second graphite sheet, and at least one intermediate graphite sheet, and the intermediate graphite sheet is located between the first graphite sheet and the second graphite sheet. In this case, the vapor chamber <NUM> has a plurality of connection layers. The quantity of connection layers is less than the quantity of graphite sheets <NUM>, and a difference between the quantity of connection layers and the quantity of graphite sheets <NUM> is one. Specifically, if the vapor chamber <NUM> has three graphite sheets <NUM>, the vapor chamber <NUM> includes a first graphite sheet, a second graphite sheet, and an intermediate graphite sheet, and there is a connection layer between the intermediate graphite sheet and each of the first graphite sheet and the second graphite sheet. If the vapor chamber <NUM> has four graphite sheets <NUM>, the vapor chamber <NUM> includes a first graphite sheet, a second graphite sheet, and two intermediate graphite sheets, a connection layer is arranged between each of the first graphite sheet and the second graphite sheet and an adjacent intermediate graphite sheet, and a connection layer is arranged between the two intermediate graphite sheets. The rest is deduced by analogy.

Referring to <FIG> and <FIG>, the middle plate <NUM> of the middle frame <NUM> is provided with a second groove <NUM>, and the vapor chamber <NUM> is mounted in the groove <NUM>. It may be understood that when the vapor chamber <NUM> is mounted in the groove <NUM>, the first graphite sheet of the vapor chamber <NUM> is in contact with a bottom wall of the groove <NUM>. When bonding glue is provided on a surface of the first graphite sheet facing away from the second graphite sheet, the vapor chamber <NUM> is bonded to the middle frame <NUM>.

An exemplary heat dissipation principle of the electronic device <NUM> provided in this embodiment is as follows: When the electronic device <NUM> is working, heat generated by the heating element <NUM> is transferred to the middle frame <NUM> through the thermally conductive gel <NUM>, and then the middle frame <NUM> transfers the heat to the vapor chamber <NUM> arranged on the middle frame <NUM>, so that the heat is dissipated in the accommodating space instead of gathering in the shielding space, which helps to avoid overheating of the heating element <NUM> due to incapability to dissipate the heat, thereby helping to resolve the problems of performance reduction and life shortening of the heating element <NUM> due to an excessive temperature rise.

An exemplary working principle of the vapor chamber <NUM> applied to the electronic device <NUM> is as follows: An electronic component on the electronic device <NUM> transfers heat to the first graphite sheet of the vapor chamber <NUM>, and then the heat is transferred to a graphite sheet <NUM> adjacent to the first graphite sheet, until the heat is transferred to the second graphite sheet, so that the heat is dissipated to the environment in which the vapor chamber <NUM> is located inside the electronic device <NUM>, which helps to prevent the heat generated by the electronic component from being concentrated and causing an excessive temperature rise thereof, thereby realizing heat dissipation.

The vapor chamber <NUM> provided in this embodiment is formed by arranging a plurality of graphite sheets <NUM> in a stacked manner, and a thermal conductivity coefficient of the material of the vapor chamber <NUM> is high, so that the vapor chamber <NUM> has a good heat conduction performance; and because there is no need to define a cavity inside the vapor chamber <NUM>, the vapor chamber <NUM> can have a relatively small thickness value. It is found through simulation experiments that when the quantity and the thicknesses of graphite sheets <NUM> in the vapor chamber <NUM> are designed under the premise that the heat dissipation performance of the vapor chamber <NUM> is basically the same as the heat dissipation performance of a heat pipe, the thickness of the vapor chamber <NUM> can be less than the thickness of the heat pipe. In this way, when the vapor chamber <NUM> is used to replace a heat pipe to assist an electronic component of the electronic device <NUM> in dissipating heat, the thickness of the electronic device <NUM> can also be correspondingly reduced, thereby facilitating the realization of a light and thin electronic device.

It can also be found through simulation experiments that if the quantity and the thicknesses of graphite sheets <NUM> in the vapor chamber <NUM> are properly designed, when the heat dissipation performance of the vapor chamber <NUM> can reach <NUM>% to <NUM>% of the heat dissipation performance of the vapor chamber, due to the low cost of the graphite material, the manufacturing cost of the vapor chamber <NUM> is much lower than the cost of the vapor chamber. That is, the vapor chamber <NUM> has a cost advantage when compared with the vapor chamber in the related art, thereby helps to reduce the cost of the electronic device <NUM> to which the vapor chamber <NUM> is applied.

In addition, when the vapor chamber <NUM> is formed by a single graphite sheet, the thickness of the single graphite sheet needs to be configured to be relatively great, so that the vapor chamber <NUM> can have good heat dissipation performance. In this case, because the graphite sheet <NUM> is manufactured through a sintering process, it is difficult to sinter the single graphite sheet with a relatively thickness, resulting in poor performance of the graphite sheet <NUM>. In this embodiment, by setting the vapor chamber <NUM> as a plurality of graphite sheets <NUM> arranged in a stacked manner, under the premise that the heat conduction performance of the vapor chamber <NUM> is basically the same, the thickness of each of the plurality of graphite sheets <NUM> may be designed to be less than the thickness of the single graphite sheet, so that the sintering difficulty of each graphite sheet <NUM> is reduced, and the manufacturing thereof is less difficult.

Still referring to <FIG> and <FIG>, in some embodiments, the connection layer may be an adhesive layer <NUM>. In this embodiment, regardless of whether the vapor chamber <NUM> includes two graphite sheets <NUM> or at least three graphite sheets <NUM>, any two adjacent graphite sheets <NUM> may be bonded together by an adhesive layer <NUM>, and the connection manner is simple. Specifically, the material of the adhesive layer <NUM> may be double-sided adhesive, and in this case, the adhesive layer <NUM> is a double-sided adhesive layer. Alternatively, the material of the adhesive layer <NUM> may be thermally conductive gel, and in this case, the adhesive layer <NUM> is a thermally conductive gel layer. When the adhesive layer <NUM> is a thermally conductive gel layer made of thermally conductive gel, compared with the double-sided adhesive layer, the thermally conductive gel layer not only plays the role of bonding, but also can transfer heat, so that the heat can be quickly transferred from the first graphite sheet to the second graphite sheet, thereby helping to improve the heat conduction capability of the vapor chamber <NUM>.

In an alternative embodiment, the connection layer may alternatively include an adhesive layer and a metal bonding layer. This embodiment is applicable to a situation in which the vapor chamber <NUM> includes at least three graphite sheets <NUM>. In this case, the vapor chamber <NUM> has a plurality of connection layers, and at least one of the plurality of connection layers is an adhesive layer, and the other connection layers are metal bonding layers. In other words, at least two adjacent graphite sheets <NUM> in the plurality of graphite sheets <NUM> may be connected by a metal bonding layer, and the remaining graphite sheets <NUM> in the plurality of graphite sheets <NUM> may be connected by an adhesive layer. Based on this arrangement, the metal bonding layer has a strong heat conduction capability because the material thereof is metal, so that the metal bonding layer can quickly conduct received heat, and then the vapor chamber <NUM> can quickly absorb the heat and transfer the heat to the surrounding environment, thereby helping to improve the heat dissipation effect. The metal bonding layer may be a copper foil layer <NUM> or an aluminum foil layer.

In the example shown in <FIG>, the vapor chamber <NUM> includes a first graphite sheet, an intermediate graphite sheet, and a second graphite sheet arranged sequentially from bottom to top. In this example, there is a connection layer between the first graphite sheet and the intermediate graphite sheet, and there is also a connection layer between the second graphite sheet and the intermediate graphite sheet. One of the two connection layers is an adhesive layer, and the other is a copper foil layer <NUM> or an aluminum foil layer.

When the vapor chamber <NUM> has four graphite sheets <NUM>, the vapor chamber <NUM> includes a first graphite sheet, a second graphite sheet, and two intermediate graphite sheets, and the vapor chamber <NUM> has three connection layers. For example, one of the three connection layers may be an adhesive layer, and the other two connection layers may be metal bonding layers. Specifically, if the connection layer between the first graphite sheet and an intermediate graphite sheet is an adhesive layer, then the connection layer between two adjacent intermediate graphite sheets and the connection layer between the second graphite sheet and an intermediate graphite sheet are metal bonding layers. Alternatively, one of the three connection layers may be a metal bonding layer, and the other two connection layers may be adhesive layers.

In addition, in the examples shown in <FIG> and <FIG>, bonding glue may be provided on a surface of the first graphite sheet facing away from the second graphite sheet, so that the first graphite sheet is bonded to the electronic device <NUM> through the bonding glue, to cause the vapor chamber <NUM> to be bonded to the electronic device <NUM>. A polyethylene terephthalate PET film <NUM> may be provided on a surface of the second graphite sheet facing away from the first graphite sheet. In this way, the polyethylene terephthalate PET film <NUM> can protect the second graphite sheet, to prevent slags from falling off the second graphite sheet. Based on this, when the vapor chamber <NUM> is applied to the electronic device <NUM>, the polyethylene terephthalate PET film <NUM> can prevent slags from falling off the second graphite sheet and avoid electric leakage in the electronic device <NUM>, so as to play the role of insulation.

The thicknesses of the graphite sheet <NUM>, the connection layer, the bonding glue, and the polyethylene terephthalate PET film <NUM> are properly designed, so that under the premise that the heat dissipation performance of the vapor chamber <NUM> is equivalent to the heat dissipation performance of the heat pipe, the minimum thickness of the vapor chamber <NUM> can be less than the minimum thickness of the heat pipe. The thickness of the connection layer may be between <NUM> and <NUM>. Similarly, the thicknesses of the bonding glue and the polyethylene terephthalate PET film <NUM> may also be between <NUM> and <NUM>.

For example, in this embodiment, the thickness of each graphite sheet <NUM> ranges from <NUM> to <NUM>. For example, the thickness of each graphite sheet <NUM> may be <NUM>, or the thickness of each graphite sheet <NUM> may be <NUM>, <NUM>, or <NUM>.

Thicknesses of at least two of the plurality of graphite sheets <NUM> are different. That is, the thicknesses of the plurality of graphite sheets <NUM> forming the vapor chamber <NUM> are partially or completely different.

The thicknesses of the plurality of graphite sheets <NUM> forming the vapor chamber <NUM> are partially different. For example, when the vapor chamber <NUM> includes three graphite sheets <NUM>, any two of the three graphite sheets <NUM> have a same thickness, and the remaining one of the three graphite sheets <NUM> has a thickness different from the thickness of the other two graphite sheets.

The thicknesses of the plurality of graphite sheets <NUM> forming the vapor chamber <NUM> are completely different. For example, in <FIG>, the vapor chamber <NUM> includes three graphite sheets <NUM>, and the three graphite sheets <NUM> are respectively a first graphite sheet, an intermediate graphite sheet, and a second graphite sheet from bottom to top. The thickness of second graphite sheet is h, the thickness of the intermediate graphite sheet is H1, and the thickness of the first graphite sheet is H2, where h, H1, and H2 all range from <NUM> to <NUM>. The magnitude relationship between h, H1, and H2 may be H2<H1<h, then the thickness of each graphite sheet <NUM> increases sequentially from bottom to top; or the magnitude relationship may be h<H1<H2, then the thickness of each graphite sheet <NUM> decreases sequentially from bottom to top; or the magnitude relationship may be H2<h<H1, then the thickness of the intermediate graphite sheet is the greatest. Examples are not given one by one again in this embodiment.

By adjusting the thickness of each graphite sheet <NUM>, the thickness of the vapor chamber <NUM> can be adjusted flexibly, so that the thickness of the vapor chamber <NUM> can be increased as much as possible based on that the thickness of the vapor chamber <NUM> does not exceed the thickness of the heat pipe, thereby helping to improve the heat dissipation performance of the vapor chamber <NUM>.

Through a proper design, the thickness of the vapor chamber <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>. In this case, when the thickness of the vapor chamber <NUM> reaches an optimal thickness value, the electronic device <NUM> to which the vapor chamber <NUM> is applied can also have a preferable thickness. It is to be noted that, the quantity of graphite sheets <NUM> needs to be properly set according to the thickness of each graphite sheet <NUM> and the total thickness of the vapor chamber <NUM>. For example, when the thickness of each graphite sheet <NUM> is the minimum thickness value (that is, <NUM>), the vapor chamber <NUM> can include at most five graphite sheets <NUM>, to prevent the thickness of the vapor chamber <NUM> from exceeding <NUM>. In addition, when the thickness of one graphite sheet <NUM> in the vapor chamber <NUM> is the maximum thickness value (that is, <NUM>), the thicknesses of the remaining graphite sheets <NUM> of the vapor chamber <NUM> are less than <NUM>, and the thickness of the vapor chamber <NUM> exceeds <NUM>.

In addition, the vapor chamber <NUM> is be constructed as that the thickness of each part is a uniform value. That is, each part of the vapor chamber <NUM> has a same thickness, so that the surface of the vapor chamber <NUM> is formed as a flat surface. Referring to <FIG>, at least two of the plurality of graphite sheets <NUM> forming the vapor chamber <NUM> have uneven thicknesses, and the at least two graphite sheets <NUM> with uneven thicknesses are adjacent to each other, provided that the total thickness of parts of the vapor chamber <NUM> is the same.

Specifically, an example in which the vapor chamber <NUM> has two graphite sheets <NUM> is used. The vapor chamber <NUM> includes a first graphite sheet and a second graphite sheet. The first graphite sheet may include a first part and a second part, and a thickness of the first part is less than a thickness of the second part. The second graphite sheet may include a third part and a fourth part, and a thickness of the third part is greater than a thickness of the fourth part. In addition, when the first graphite sheet is connected to the second graphite sheet, the third part exactly faces the first part, the fourth part exactly faces the second part, and a sum of the thicknesses of the third part and the first part is equal to a sum of the thicknesses of the fourth part and the second part, so that the thickness of the vapor chamber <NUM> formed by the two graphite sheets <NUM> is even. In this embodiment, both the first graphite sheet and the second graphite sheet are in a step shape.

In the following examples not covered by the scope of the claims, the vapor chamber <NUM> may alternatively be constructed as that the thickness value of each part is not uniform. That is, each part of the vapor chamber <NUM> has a different thickness.

In a possible example, referring to <FIG>, the vapor chamber <NUM> has at least one graphite sheet <NUM> with an uneven thickness. For example, in the example shown in <FIG>, the vapor chamber <NUM> includes a first graphite sheet and a second graphite sheet that are sequentially arranged in a stacked manner from bottom to top. The thickness of the second graphite sheet is even, and the thickness of the first graphite sheet is uneven, so that the thickness of the vapor chamber <NUM> formed by the first graphite sheet and the second graphite sheet is uneven.

In another possible example, referring to <FIG>, the vapor chamber <NUM> includes a first region and a second region, and the thickness of the first region is different from the thickness of the second region. In addition, the quantity of graphite sheets <NUM> at the first region is different from the quantity of graphite sheets at the second region. For example, in the example shown in <FIG>, the vapor chamber <NUM> includes a first graphite sheet and a second graphite sheet that are sequentially arranged in a stacked manner from bottom to top. In a thickness direction of the vapor chamber, a cross-sectional area of the first graphite sheet is smaller than a cross-sectional area of the second graphite sheet, and the first graphite sheet is designed as that an orthographic projection thereof on the middle plate <NUM> partially overlaps with an orthographic projection of the second graphite sheet on the middle plate <NUM>, so that the vapor chamber <NUM> has two layers of graphite sheets at a region at which the first graphite sheet and the second graphite sheet overlap, and has only one layer of graphite sheet at a region at which the first graphite sheet and the second graphite sheet do not overlap, thereby realizing different thicknesses of at least two parts of the vapor chamber <NUM>. It is to be noted that, in this embodiment, the thickness of each graphite sheet <NUM> forming the vapor chamber <NUM> is even.

Certainly, the vapor chamber <NUM> may also include a plurality of regions with different thicknesses, and the quantities of graphite sheets at the plurality of regions are different, so that the thicknesses of plurality of parts of the vapor chamber <NUM> are different.

It may be understood that when the vapor chamber <NUM> includes at least three graphite sheets <NUM>, the vapor chamber <NUM> includes a first graphite sheet, an intermediate graphite sheet, and a second graphite sheet that are sequentially arranged in a stacked manner from bottom to top. The first graphite sheet or the second graphite sheet is configured to overlap with only a partial region of the intermediate graphite sheet. In other words, by designing any one of the outermost graphite sheets <NUM> of the vapor chamber <NUM> to have a cross-sectional area smaller than a cross-sectional area of the intermediate graphite sheet, the vapor chamber <NUM> has two regions with different thicknesses, thereby realizing an uneven thickness of the vapor chamber <NUM>. In addition, this arrangement can also maintain good stability of the entire vapor chamber <NUM>.

A surface of the display screen <NUM> facing the middle plate <NUM> is connected to a plurality of pieces of foam <NUM>, and thicknesses of the plurality of pieces of foam <NUM> may be the same or different. Therefore, by designing the vapor chamber <NUM> to be equal in thickness, the thickness of the vapor chamber <NUM> can be adapted to the thickness of the foam <NUM>, then the vapor chamber <NUM> is in contact with a surface of each of the plurality of pieces of foam <NUM> facing away from the display screen <NUM>, and then a contact area between the vapor chamber <NUM> and the foam <NUM> can be maximized, thereby helping to ensure good stability of the display screen <NUM>.

Specifically, in <FIG>, a surface of the display screen <NUM> facing the middle plate <NUM> is connected to a plurality of pieces of foam <NUM>, and the plurality of pieces of foam <NUM> have a same thickness. Correspondingly, the thickness of each part of the vapor chamber <NUM> is the same. In this way, the surfaces of the plurality of pieces of foam <NUM> facing the vapor chamber <NUM> are flat surfaces, and the surface of the vapor chamber <NUM> facing the display screen <NUM> is also a flat surface.

In <FIG>, the surface of the display screen <NUM> facing the middle plate <NUM> is connected to first foam 11a and second foam 11b, and a thickness of the first foam 11a is less than a thickness of the second foam 11b. Correspondingly, a thickness of a part on the vapor chamber <NUM> opposite to the first foam 11a is greater than a thickness of a part on the vapor chamber <NUM> opposite to the second foam 11b.

In some examples, the thickness of the vapor chamber <NUM> is not greater than a depth of the groove <NUM>. That is, the thickness of the vapor chamber <NUM> is less than the depth of the groove <NUM>, or the thickness of the vapor chamber <NUM> is the same as the depth of the groove <NUM>. In this case, the surface of the vapor chamber <NUM> facing away from the circuit board <NUM> and the surface of the middle plate <NUM> facing away from the circuit board <NUM> are coplanar. With such a design, the vapor chamber <NUM> does not extend from the groove <NUM> into the accommodating space, which helps to prevent a part of the vapor chamber <NUM> from occupying the accommodating space and resulting in reduction of the accommodating space. Therefore, the accommodating space can be configured to accommodate more or larger electronic components or components.

The display screen <NUM> has a front surface and a back surface. The front surface is a surface of the display screen <NUM> facing a user, and the back surface is a surface of the display screen <NUM> facing away from the user. Referring to <FIG>, in some embodiments of this application, orthographic projections of the heat conduction element and the heating element <NUM> on the back surface of the display screen <NUM> in a direction perpendicular to the middle plate <NUM> fall within an orthographic projection of the vapor chamber <NUM> on the back surface of the display screen <NUM>. That is, the heating element <NUM> and the vapor chamber <NUM> are oppositely located on two sides of the middle frame <NUM>. With such a design, when the middle frame <NUM> transfers heat emitted by the heating element <NUM> to the vapor chamber <NUM>, a heat transfer path between the middle frame <NUM> and the vapor chamber <NUM> is the shortest, so that the heat generated by the heating element <NUM> can be quickly transferred to the vapor chamber <NUM>, thereby helping to improve the cooling rate of the heating element <NUM>.

The shapes of the groove <NUM> and the vapor chamber <NUM> are not limited. For example, both the groove <NUM> and the vapor chamber <NUM> may be rectangular. Preferably, when a plurality of heating elements <NUM> are arranged on the first surface of the circuit board <NUM>, the shape of the vapor chamber <NUM> is properly designed according to the layout manner of the plurality of heating elements <NUM>, so that orthographic projections of the plurality of heating elements <NUM> arranged on the first surface of the circuit board <NUM> on the back surface of the display screen <NUM> can all be within the orthographic projection of the vapor chamber <NUM> on the back surface of the display screen <NUM>.

In some examples, the vapor chamber <NUM> may include a rectangular plate body <NUM> and a heat conduction plate body <NUM>. The shape of the heat conduction plate body <NUM> is adapted to the shape constructed by the heating elements <NUM> arranged on the first surface of the circuit board <NUM>, so that projections of the heating elements <NUM> on the vapor chamber <NUM> are all located on the heat conduction plate body <NUM>. Based on this arrangement, a heat transfer path between each heating element <NUM> arranged on the first surface of the circuit board <NUM> and the vapor chamber <NUM> can be the shortest, so that the heat generated by these heating elements <NUM> can all be quickly conducted to the vapor chamber <NUM>, thereby making the heating element <NUM> dissipate heat quickly. In addition, compared with directly arranging a vapor chamber <NUM> with a relatively large size, the vapor chamber <NUM> in this embodiment is provided with a heat conduction plate body <NUM> adapted to the heating elements <NUM>. On the basis of corresponding to these heating elements <NUM>, the size of the vapor chamber <NUM> can be reduced as much as possible, and then the size of the groove <NUM> can also be made as small as possible, so as to help to prevent the groove <NUM> from being excessively large and causing insufficient structural strength of the middle frame <NUM>, thereby ensuring that the middle frame <NUM> can stably carry components such as the circuit board <NUM> and the display screen <NUM>.

For example, as shown in <FIG>, two heating elements <NUM> are arranged on the first surface of the circuit board <NUM>. The two heating elements <NUM> are spaced apart in a length direction of the electronic device <NUM>, where one heating element <NUM> is located in the middle of the circuit board <NUM>, and the other heating element <NUM> is located on a right side of the circuit board <NUM>. Correspondingly, the heat conduction plate body <NUM> is rectangular, and the rectangular heat conduction plate body <NUM> has a part protruding out of the rectangular plate body <NUM> of the vapor chamber <NUM>, to exactly face the heating element <NUM> on the right side of the circuit board <NUM>.

In another example, as shown in <FIG>, three heating elements <NUM> are arranged on the first surface of the circuit board <NUM>. The three heating elements <NUM> are spaced apart in a width direction of the electronic device <NUM>, and the heating element <NUM> in the middle is located above the other two the heating elements <NUM>. Correspondingly, the heat conduction plate body <NUM> is convex, so that the protruding part at the middle and upper end of the heat conduction plate body <NUM> exactly faces the heating element <NUM> in the middle, and the protruding parts on two sides of the heat conduction plate body <NUM> exactly face the other two heating elements <NUM> respectively. Certainly, in other embodiments of this application, the vapor chamber <NUM> may alternatively be in other shapes, which will not be listed herein.

It is to be noted that the relative positional relationship between the heating elements <NUM> and the heat conduction plate body <NUM> is that: all the heating elements <NUM> exactly face the heat conduction plate body, a minimum value of distances between first side edges of all the heating elements <NUM> and a same side edge of the heat conduction plate body <NUM> is a first distance a, and a minimum value of distances between second side edges of all the heating elements <NUM> and a same side edge of the heat conduction plate body <NUM> is a second distance b. The first side and the second side are opposite sides of the heating element <NUM> in the width direction of the electronic device <NUM>. That is, the first side may be the left side of the heating element <NUM>, and on the contrary, the second side is the right side of the heating element <NUM>; or the first side may be the right side of the heating element <NUM>, and on the contrary, the second side is the left side of the heating element <NUM>.

In addition, a minimum value of distances between third side edges of all the heating elements <NUM> and a same side edge of the heat conduction plate body <NUM> is a third distance c, and a minimum value of distances between fourth side edges of all the heating elements <NUM> and a same side edge of the heat conduction plate body <NUM> is a fourth distance d. The third side and the fourth side are opposite sides of the heating element <NUM> in the length and width direction of the electronic device <NUM>. That is, the third side may be the upper side of the heating element <NUM>, and on the contrary, the fourth side is the lower side of the heating element <NUM>; or the third side may be the lower side of the heating element <NUM>, and on the contrary, the fourth side is the upper side of the heating element <NUM>.

In addition, a, b, c, and d are all greater than <NUM>. That is, the first distance, the second distance, the third distance, and the fourth distance are all positive numbers, so that the projection of the heating element <NUM> on the heat conduction plate body <NUM> is completely in the middle of the heat conduction plate body <NUM>.

That is, the heat conduction plate body <NUM> is configured as that a left side edge thereof exceeds the leftmost side edge of all heating elements <NUM>, and the excess distance is a first distance a; a right side edge of the heat conduction plate body <NUM> exceeds the rightmost side edge of all heating elements <NUM>, and the excess distance is a second distance b; an upper side edge of the heat conduction plate body <NUM> exceeds the uppermost side edge of all heating elements <NUM>, and the excess distance is a third distance c; and a lower side edge of the heat conduction plate body <NUM> exceeds the lowermost side edge of all heating elements <NUM>, and the excess distance is a fourth distance d.

Based on this arrangement, the projection of the heating element <NUM> on the heat conduction plate body <NUM> is completely located in the middle of the heat conduction plate body <NUM>, and the heat conduction range of the heat conduction plate body <NUM> can completely cover the surroundings of the heating element <NUM>, so that the heat generated by the heating element <NUM> can all be dissipated from the surroundings and transferred to the heat conduction plate body <NUM>, thereby facilitating heat dissipation of the electronic device <NUM>.

An example in which the first side is the left side of the heating element <NUM>, and the third side is the upper side of the heating element <NUM> is used for illustration below.

In <FIG>, when one heating element <NUM> is arranged on the first surface of the circuit board <NUM>, a distance between a left edge of the heating element <NUM> and a left edge of the heat conduction plate body <NUM> is a first distance a, a distance between a right edge of the heating element <NUM> and a right edge of the heat conduction plate body <NUM> is a second distance b, a distance between an upper edge of the heating element <NUM> and an upper edge of the heat conduction plate body <NUM> is a third distance c, and a distance between a lower edge of the heating element <NUM> and a lower edge of the heat conduction plate body <NUM> is a fourth distance d.

In <FIG>, when two heating elements <NUM> are arranged on the first surface of the circuit board <NUM>, a distance between a left edge of the more left one of the two heating elements <NUM> and a left edge of the heat conduction plate body <NUM> is a first distance a, a distance between a right edge of the more right one of the two heating elements <NUM> and a right edge of the heat conduction plate body <NUM> is a second distance b, a distance between an upper edge of the upper one of the two heating elements <NUM> and an upper edge of the heat conduction plate body <NUM> is a third distance c, and a distance between a lower edge of the lower one of the two heating elements <NUM> and a lower edge of the heat conduction plate body <NUM> is a fourth distance d.

In <FIG>, when three heating elements <NUM> are arranged on the first surface of the circuit board <NUM>, a distance between a left edge of the leftmost one of the three heating elements <NUM> and a left edge of the heat conduction plate body <NUM> is a first distance a, a distance between a right edge of the rightmost one of the three heating elements <NUM> and a right edge of the heat conduction plate body <NUM> is a second distance b, a distance between an upper edge of the uppermost one of the three heating elements <NUM> and an upper edge of the heat conduction plate body <NUM> is a third distance c, and a distance between a lower edge of the lowermost one of the three heating elements <NUM> and a lower edge of the heat conduction plate body <NUM> is a fourth distance d.

Values of the first distance a, the second distance b, the third distance c, and the fourth distance d are not limited. In some examples, the first distance a and the second distance b may be equal or may not be equal. When the first distance a and the second distance b are equal, the distance by which the left edge of the heat conduction plate body <NUM> exceeds the left edge of the heating element <NUM> located on the leftmost side is equal to the distance by which the right edge of the heat conduction plate body <NUM> exceeds the right edge of the heating element <NUM> located on the rightmost side, thereby making the heat dissipation relatively even. Similarly, the third distance c and the fourth distance d may be equal or may not be equal. When the third distance c and the fourth distance d are equal, the distance by which the upper edge of the heat conduction plate body <NUM> exceeds the upper edge of the heating element <NUM> located on the uppermost side is equal to the distance by which the lower edge of the heat conduction plate body <NUM> exceeds the lower edge of the heating element <NUM> located on the lowermost side, thereby making the heat dissipation relatively even.

Certainly, when the first distance a is the same as the second distance b, and the third distance c is the same as the fourth distance d, the first distance a and the third distance c may also be equal. In this embodiment, the distances by which the heat conduction plate body <NUM> exceeds the surrounding edges of the heating element <NUM> are the same, so that the ranges of heat transfer from the surroundings of the heating element <NUM> to the vapor chamber <NUM> are basically the same, thereby facilitating even heat dissipation.

Specifically, both the first distance a and the second distance b may be greater than or equal to <NUM> and less than or equal to <NUM>, and the third distance c and the fourth distance d may also be greater than or equal to <NUM> and less than or equal to <NUM>.

The size of the rectangular plate body <NUM> of the vapor chamber <NUM> may be properly designed according to the size of the groove. For example, a width W' of the rectangular plate body <NUM> of the vapor chamber <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>, and a length L' of the rectangular plate body <NUM> of the vapor chamber <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>.

With reference to the first distance a, the second distance b, the width value range of the rectangular plate body <NUM>, and the layout of the heating element, a width W of the entire vapor chamber <NUM> may be designed to be greater than or equal to <NUM> and less than or equal to <NUM>; and with reference to the third distance c, the fourth distance d, the length value range of the rectangular plate body <NUM>, and the layout of the heating element, a length L of the entire vapor chamber <NUM> may be designed to be greater than or equal to <NUM> and less than or equal to <NUM>.

Still referring to <FIG> and <FIG>, the electronic device <NUM> may further include a battery <NUM>. The battery <NUM> is also one of the electronic components of the electronic device <NUM>, and is configured to supply power for the display screen <NUM>, the heating element <NUM>, and the like. The battery <NUM> is arranged on the side of the middle frame <NUM> facing away from the display screen <NUM>, and the battery <NUM> and the circuit board <NUM> are spaced apart in the length direction of the middle frame <NUM>. It is to be further noted that the circuit board <NUM> is arranged close to the top of the middle frame <NUM>, to facilitate communication between the <NUM> PA and/or <NUM> PA on the circuit board <NUM> and a base station.

A part of the battery <NUM> and a part of the vapor chamber <NUM> are oppositely arranged on two sides of the middle frame <NUM>. Therefore, the distance between the battery <NUM> and the vapor chamber <NUM> is relatively short, then a relatively short heat conduction path can be formed between the battery <NUM> and the vapor chamber <NUM>, and some heat dissipated by the battery <NUM> during working can be quickly transferred to the vapor chamber <NUM> through the middle frame <NUM>, thereby helping to resolve the problem of overheating of the electronic device <NUM> due to an excessively rapid temperature rise of the battery <NUM>. It can be easily seen from this embodiment that because the vapor chamber <NUM> is not opposite to the entire battery <NUM>, the vapor chamber <NUM> is arranged close to the top of the middle frame <NUM>, and the bottom of the vapor chamber <NUM> does not extend to the bottom of the middle frame <NUM>.

It may also be understood that in this embodiment, there are the following possible examples for the formation manner of the groove <NUM>: In an example, the groove <NUM> is a blind hole, that is, the depth of the entire groove <NUM> is less than the thickness of the middle plate <NUM>. In this way, the surface of the vapor chamber <NUM> facing away from the display screen <NUM> is completely in contact with the bottom wall of the groove <NUM>, and the vapor chamber <NUM> is completely separated from the battery <NUM> or the circuit board <NUM> by the middle frame <NUM>.

In another example, as shown in <FIG>, an opening is provided on the middle plate <NUM> of the middle frame <NUM>, and an inner side wall of the opening is provided with an overlap edge <NUM> protruding into the opening. The overlap edge <NUM> and the middle frame <NUM> jointly form the groove <NUM>. In this way, a part of the surface of the vapor chamber <NUM> facing away from the display screen <NUM> is in contact with the bottom wall of the groove <NUM>, and the middle frame <NUM> does not completely separate the vapor chamber <NUM> from the battery <NUM> or the circuit board <NUM>, provided that the heating element <NUM> can be in contact with the middle frame <NUM> through the heat conduction element.

The overlap edge <NUM> may be connected to the entire circumferential inner side wall of the opening. Alternatively, as shown in <FIG>, a partial circumferential inner side wall of the opening is provided with an overlap edge <NUM> in a protrusion manner. In other words, a notch is formed on the overlap edge <NUM>, so that a through hole is formed on the middle plate <NUM> of the middle frame <NUM>. Specifically, in the example shown in <FIG>, the notch is provided close to the bottom of the groove <NUM>, so that a through hole is formed at a part of the vapor chamber <NUM> corresponding to the battery <NUM> on the middle frame <NUM>, then the part of the vapor chamber <NUM> opposite to the battery <NUM> is not separated by the middle frame <NUM>. Therefore, both a part of the heat of the battery <NUM> and a part of the heat of the vapor chamber <NUM> can be dissipated in the through hole, thereby facilitating quick heat dissipation of the battery <NUM> and the vapor chamber <NUM>. In the example shown in <FIG> and <FIG>, the notch is provided close to the top of the groove <NUM>, so that a through hole is provided at a part of the vapor chamber <NUM> corresponding to the circuit board <NUM> on the middle frame <NUM>, then the vapor chamber <NUM> and the circuit board <NUM> are not completely separated by the middle frame <NUM>. Therefore, a part of the heat of the heating element <NUM> and the vapor chamber <NUM> can be dissipated in the through hole, thereby facilitating quick heat dissipation of the heating element <NUM> and the vapor chamber <NUM>.

Based on the foregoing embodiments, referring to <FIG>, the electronic device <NUM> further includes a heat sink <NUM>, and the heat sink <NUM> is configured to assist other electronic components on the electronic device <NUM> in dissipating heat, so as to further improve the heat dissipation performance of the electronic device <NUM>, thereby helping to reduce the possibility of overheating of the electronic device <NUM>.

<FIG> is a cross-sectional view of another electronic device <NUM> taken in a direction of a reference line L-L in <FIG> according to this embodiment. Referring to <FIG>, and <FIG>, the heat sink <NUM> may include a first heat dissipation portion <NUM> mounted on the middle frame <NUM>, and the first heat dissipation portion <NUM> is also arranged between the vapor chamber <NUM> and the display screen <NUM>. With such a design, when the electronic device <NUM> is working, the vapor chamber <NUM> receives the heat transferred by the heating element <NUM> and/or the battery <NUM> and conducts the heat to the first heat dissipation portion <NUM>, then the first heat dissipation portion <NUM> can help the vapor chamber <NUM> dissipate the heat, thereby improving the heat dissipation efficiency of the vapor chamber <NUM>, and further improving the heat dissipation performance of the electronic device <NUM>.

When the thickness of the vapor chamber <NUM> is less than the depth of the groove <NUM>, there is a gap between the vapor chamber <NUM> and the first heat dissipation portion <NUM>. In this example, the first heat dissipation portion <NUM> may be bonded to the middle frame <NUM>.

When the depth of the groove <NUM> is the same as the thickness of the vapor chamber <NUM>, the first heat dissipation portion <NUM> is in conflict with the vapor chamber <NUM> and the middle plate <NUM> of the middle frame <NUM>, and the middle frame <NUM> can stably support the first heat dissipation portion <NUM>. Compared with existence of the gap between the first heat dissipation portion <NUM> and the vapor chamber <NUM>, in this embodiment, the vapor chamber <NUM> can directly transfer heat to the first heat dissipation portion <NUM>, and the heat transfer efficiency is high. The first heat dissipation portion <NUM> may be connected to the vapor chamber <NUM> and the middle frame <NUM> in a bonding manner.

Still referring to <FIG> and <FIG>, in the thickness direction of the middle plate <NUM>, the orthographic projection of the vapor chamber <NUM> on the back surface of the display screen <NUM> is located within the orthographic projection of the first heat dissipation portion <NUM> on the back surface of the display screen <NUM>. That is, the first heat dissipation portion <NUM> can completely cover the vapor chamber <NUM>, then the heat on the vapor chamber <NUM> can be transferred to the first heat dissipation portion <NUM> as much as possible, so that the electronic device <NUM> has good heat dissipation performance.

In a possible implementation, the structure of the first heat dissipation portion <NUM> may be the same as the structure of the vapor chamber <NUM>. That is, the first heat dissipation portion <NUM> may also include a plurality of graphite sheets <NUM> arranged in a stacked manner. Certainly, the first heat dissipation portion <NUM> may also be any one of a single graphite sheet, copper foil, aluminum foil, a vapor chamber, or a heat pipe in the related art, which is not limited in this embodiment.

Further, the heat sink <NUM> may further include a second heat dissipation portion <NUM> mounted on the middle plate <NUM> of the middle frame <NUM>, where the second heat dissipation portion <NUM> is located between the middle frame <NUM> and the display screen <NUM>, and the second heat dissipation portion <NUM> and the first heat dissipation portion <NUM> are spaced apart in the length direction of the middle frame <NUM>, so that the second heat dissipation portion <NUM> and the first heat dissipation portion <NUM> are side by side. By arranging the second heat dissipation portion <NUM>, the middle frame <NUM> can transfer the heat generated by the battery <NUM> and/or the heating element <NUM> to the second heat dissipation portion <NUM>, so that the middle frame <NUM> can quickly dissipate heat and cool down.

Similar to the first heat dissipation portion <NUM>, the second heat dissipation portion <NUM> may be formed by a single graphite sheet, or may be formed by a plurality of graphite sheets <NUM>, or may be any one of copper foil, aluminum foil, a vapor chamber, or a heat pipe in the related art.

The electronic device <NUM> may further include a rear cover <NUM>, and the rear cover <NUM> is arranged on a side of the middle frame <NUM> facing away from the display screen <NUM>. Both the circuit board <NUM> and the battery <NUM> are arranged between the middle frame <NUM> and the rear cover <NUM>, and the rear cover <NUM> can protect the battery <NUM> and the circuit board <NUM>. Based on this, the heat sink <NUM> may further include a third heat dissipation portion <NUM>, and the third heat dissipation portion <NUM> is arranged between the battery <NUM> and the rear cover <NUM>. With such a design, when the electronic device <NUM> is working, a part of the heat generated by the battery <NUM> can be transferred to the third heat dissipation portion <NUM>, and then the third heat dissipation portion <NUM> conducts the received heat to the rear cover <NUM>, so that the battery <NUM> can dissipate heat and cool down.

With reference to the foregoing description and <FIG>, when a heating element <NUM> is arranged on the second surface of the circuit board <NUM>, a shielding cover <NUM> is arranged on the second surface of the circuit board <NUM>. The shielding cover <NUM> and the second surface of the circuit board <NUM> jointly define a shielding space for accommodating the heating element <NUM>. The heating element <NUM> arranged on the second surface is connected to the shielding cover <NUM> through thermally conductive gel <NUM>, and thermally conductive gel <NUM> is also provided between the shielding cover <NUM> and the third heat dissipation portion <NUM>. In this way, the heat generated by the heating element <NUM> arranged on the second surface can be conducted to the third heat dissipation portion <NUM> through the thermally conductive gel <NUM>, then the third heat dissipation portion <NUM> transfers the heat to the rear cover <NUM>, and the rear cover <NUM> emits the heat and dissipates the heat in the external environment, so that the heating element <NUM> arranged on the second surface can dissipate heat, thereby preventing the performance of the heating element <NUM> arranged on the second surface from being affected due to heat accumulation. In general, by arranging the third heat dissipation portion <NUM>, the heat generated by the battery <NUM> and the heating element <NUM> arranged on the second surface can be evenly transferred to the rear cover <NUM>.

The third heat dissipation portion <NUM> may be connected to the rear cover <NUM> in a bonding manner. For the structure of the third heat dissipation portion <NUM>, reference may be made to the structure of the first heat dissipation portion <NUM>. That is, the third heat dissipation portion <NUM> may be a single graphite sheet, or may be any one of copper foil, aluminum foil, a vapor chamber, or a heat pipe in the related art.

In addition, as shown in <FIG>, a vapor chamber <NUM> may also be provided between the circuit board <NUM> and the third heat dissipation portion <NUM>. Specifically, the shielding cover <NUM> is in contact with the vapor chamber <NUM> through the thermally conductive gel <NUM>. In this embodiment, the heat generated by the heating element <NUM> arranged on the second surface can be transferred to the vapor chamber <NUM> first, and then the vapor chamber <NUM> conducts the heat to the third heat dissipation portion <NUM> and the rear cover <NUM>. It can be seen that the vapor chamber <NUM> arranged between the circuit board <NUM> and the rear cover <NUM> can assist the heating element <NUM> in heat conduction, so that the heating element <NUM> can dissipate heat as soon as possible, thereby helping to improve the heat dissipation performance of the electronic device <NUM>.

Referring to <FIG>, an example further provides an electronic device <NUM>. The electronic device <NUM> also includes a display screen <NUM>, a middle frame <NUM>, a circuit board <NUM>, a heating element <NUM>, a heat conduction element, and a vapor chamber <NUM>. Different from example <NUM>, in this example the vapor chamber <NUM> is arranged between the middle frame <NUM> and the circuit board <NUM>, and the heating element <NUM> is in contact with the vapor chamber through the heat conduction element.

An exemplary heat dissipation principle of the electronic device <NUM> provided in this example is as follows: When the electronic device <NUM> is working, the heat generated by the heating element <NUM> is transferred to the vapor chamber <NUM> through the thermally conductive gel <NUM>, then the vapor chamber <NUM> transfers the heat to the middle frame <NUM> in contact with the vapor chamber, and subsequently the middle frame <NUM> is in contact with the external environment to dissipate the heat in the external environment, thereby helping to avoid the problems of performance reduction and life shortening of the heating element <NUM> due to an excessive temperature rise.

The structure of the vapor chamber <NUM> in this example is the same as the structure of the vapor chamber in Example <NUM>, and details will not be described herein again.

In the description of the embodiments of this application, it is to be noted that, unless otherwise explicitly specified and defined, the terms "mount", "connect", and "connection" should be understood in a broadest sense, for example, fixed connection, indirect connection by a medium, or internal communication between two elements or an interaction relationship between the two elements. A person of ordinary skill in the art may understand the specific meanings of the foregoing terms in the embodiments of this application according to specific situations.

In the embodiments of this application, orientation or location relationships do not indicate or imply that the mentioned apparatus or element needs to have a particular orientation, or needs to be constructed and operated in a particular orientation, and therefore cannot be construed as a limitation on the embodiments of this application. In the description of the embodiments of this application, unless otherwise exactly and specifically specified, "a plurality of" means two or more than two.

The terms such as "first", "second", "third", and "fourth" (if any) in the specification and claims of the embodiments of this application and in the accompanying drawings are used for distinguishing between similar objects and not necessarily used for describing any particular order or sequence. It may be understood that the data termed in such a way is interchangeable in proper circumstances, so that the embodiments of this application described herein, for example, can be implemented in other orders than the order illustrated or described herein. In addition, the terms "include", "contain" and any other variants mean to cover the non-exclusive inclusion, for example, a process, method, system, product, or device that includes a list of steps or units is not necessarily limited to those expressly listed steps or units, but may include other steps or units not expressly listed or inherent to such a process, method, system, product, or device.

Claim 1:
A heat-equalizing plate (<NUM>), suitable to be applied to an electronic device (<NUM>), and comprising a plurality of graphite sheets (<NUM>) made of a graphite material or a graphene material, wherein the plurality of graphite sheets are arranged in a stacked manner, and a connection layer (<NUM>) is arranged between two adjacent graphite sheets,
wherein thicknesses of at least two of the plurality of graphite sheets are different, wherein the heat-equalizing plate comprises at least two graphite sheets with uneven thicknesses, and characterised in that the at least two graphite sheets with uneven thicknesses are adjacent to each other such that a thickness of each part of the heat-equalizing plate is the same.