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

With rapid development of terminal device technologies, an electronic device with only one display cannot meet a requirement of a user in different scenarios. Therefore, an electronic device with two screens, such as a dual screen mobile phone, is proposed in a related technology.

Currently, a dual screen mobile phone is usually provided with a middle frame, a first display, and a second display, and the first display and the second display are respectively disposed on two sides of the middle frame. The dual screen mobile phone further includes electronic elements such as a mainboard, a speaker, and a battery. The electronic elements such as the mainboard, the speaker, and the battery are all built in between the first display and the second display, and both the first display and the second display are electrically connected to the mainboard. Specifically, a flexible printed circuit board (Flexible Printed Circuit board; FPC) is disposed on the first display. The flexible printed circuit board is wound around a surface that is of the mainboard and that faces the second display, and is electrically connected to the surface that is of the mainboard and that faces the second display. In addition, the second display is also connected to the surface that is of the mainboard and that faces the second display.

However, in the foregoing dual screen mobile phone, when the first display is faulty and needs to be repaired or replaced, the second display, the mainboard, and components located between the mainboard and the second display all need to be detached. A detachment process is complex, and the electronic elements such as the second display and the mainboard may be easily damaged in the detachment process. This results in high detachment costs.

<CIT> relates to a mobile terminal which includes a screen, a front case, a main board and a connector; a flexible circuit board is connected to the screen and the flexible circuit board is connected to the main board through the connector.

Furthermore, the front case is provided with a through hole at a position corresponding to the connector. The flexible circuit board is connected to the main board through the through hole.

<CIT> relates to a flexible circuit board that is used in a multi-screen display device. The multi-screen display device is provided with a primary display screen and at least one secondary display screen. The flexible circuit board includes a circuit board main body, connector extending ends arranged at the edge of the circuit board main body, binding end extending ends of the auxiliary display screens and binding ends of the main display screen, circuit structures of all the display screens of the multi-screen display equipment are integrated on the circuit board main body, the connector extending ends are in one-to-one correspondence with the display screens, and the binding end extending ends are in one-to-one correspondence with the auxiliary display screens.

Embodiments of this application provide an electronic device, so as to resolve problems of a complex detachment process and high detachment costs of a first display of a dual screen mobile phone in the conventional technology.

The present invention provides an electronic device, including a middle frame, a first display, a second display, a mainboard, a first flexible printed circuit board, and a second flexible printed circuit board.

A middle frame includes a middle plate and a frame connected to a circumferential edge of the middle plate, where an opening is disposed on the middle plate.

A first display and a second display are respectively disposed on two sides of the middle plate, and the mainboard is mounted on the middle plate and faces the opening.

One end of the first flexible printed circuit board is connected to a surface that is of the first display and that faces the middle plate, and the other end of the first flexible printed circuit board extends between the first display and the mainboard and is electrically connected to a surface that is of the mainboard and that faces the first display.

One end of the second flexible printed circuit board is connected to a surface that is of the second display and that faces the middle plate, and the other end of the second flexible printed circuit board extends between the second display and the mainboard and is electrically connected to a surface that is of the mainboard and that faces the second display.

The electronic device provided in this embodiment of this application includes two displays, namely the first display and the second display, and the mainboard located between the two displays. The first flexible printed circuit board on the first display is electrically connected to the surface that is of the mainboard and that faces the first display, and the second flexible printed circuit board on the second display is electrically connected to the surface that is of the mainboard and that faces the second display. That is, neither of the two flexible printed circuit boards is wound around two sides of the mainboard. In this way, when the first display needs to be repaired or replaced due to crack, scraping, poor contact, or another reason, the first display may be directly pulled to move away from a direction of the mainboard, and components such as the second display and the mainboard do not need to be detached, and a detachment process is simple. In addition, this prevents electronic elements such as the mainboard and the second display from being damaged due to collision or scraping in the detachment process, thereby avoiding high repair costs. In a possible implementation, the electronic device further includes a locking bracket disposed between the mainboard and the first display, where the locking bracket is detachably connected to the middle frame, and the locking bracket is in contact with a surface that is of the first flexible printed circuit board and that faces the first display.

In a possible implementation, a first mounting base and a second mounting base protrude from the middle plate, the first mounting base and the second mounting base are disposed on two sides opposite to the opening, and two ends of the locking bracket are detachably connected to the first mounting base and the second mounting base, respectively.

In a possible implementation, each of the first mounting base and the second mounting base, and the middle plate form an integrated component by using an integrated molding process.

In a possible implementation, the first flexible printed circuit board is connected to the surface that is of the mainboard and that faces the first display by using a connector, the connector includes a male socket and a female socket, the male socket is disposed on a surface that is of the first flexible printed circuit board and that faces the mainboard, and the female socket is disposed on the surface that is of the mainboard and that faces the first display, and the female socket is inserted into the male socket; and a clamping gap is jointly defined between the locking bracket and the mainboard, and the first flexible printed circuit board and the connector are clamped in the clamping gap.

In a possible implementation, the electronic device further includes a cover plate disposed between the mainboard and the second display, where the cover plate covers on the mainboard.

In a possible implementation, the first flexible printed circuit board includes a bent segment and a connection segment that are connected, one end that is of the bent segment and that is away from the connection segment is connected to the first display, and the connection segment is electrically connected to the surface that is of the mainboard and that faces the first display.

In a possible implementation, both the bent segment and the connection segment are located between the mainboard and the first display.

In a possible implementation, the electronic device further includes a functional component, where the functional component and the mainboard are located on a same side of the middle plate, the functional component and the mainboard are disposed side by side along a length direction of the electronic device, and the bent segment and a part of connection segment are disposed between the functional component and the first display.

In a possible implementation, the mainboard and the second display are located on a same side of the middle plate, the functional component faces the opening, a protruding portion is disposed on a surface that is of the functional component and that faces the first display, the protruding portion extends from the opening to a side that is of the middle plate and that faces the first display, a surface that is of the functional component and that faces the first display and the protruding portion jointly define a step surface, the step surface and the first display are jointly enclosed into an avoidance groove, and the bent segment is disposed in the avoidance groove.

In a possible implementation, the bent segment is located on a side that is of the protruding portion and that is away from the mainboard, the connection segment extends from a position between the protruding portion and the first display to a position between the mainboard and the first display, and a surface that is of the connection segment and that faces the mainboard is attached to the protruding portion.

In a possible implementation, the first flexible printed circuit board includes a fastening segment, the fastening segment is connected to a surface that is of the first display and that faces the mainboard, and the fastening segment is connected to the one end that is of the bent segment and that is away from the connection segment.

In a possible implementation, the functional component is a camera, or the functional component is a speaker.

In a possible implementation, the bent segment is arc-shaped, or the bent segment has a bent angle. In a possible implementation, the electronic device further includes a battery, where the battery and the mainboard are disposed on a same side of the middle plate, and the battery is electrically connected to the mainboard.

In a possible implementation, the electronic device further includes a rear cover, where the rear cover and the second display are located on a same side of the middle plate; and the battery is disposed between the back cover and the first display, or the battery is disposed between the first display and the second display.

In a possible implementation, the first display is a flexible display that can be folded, the middle frame includes a first structural member, a rotating assembly, and a second structural member, and the first structural member is rotatably connected to the second structural member by using the rotating assembly.

To meet differentiated needs of users, an electronic device with two screens has emerged. <FIG> schematically shows a breakdown structure of a dual screen mobile phone in a related technology; and <FIG> schematically shows a cross-sectional structure of a dual screen mobile phone in a related technology. Referring to <FIG>, the dual screen mobile phone provided in the related technology includes a middle frame 10a, a first display 20a, and a second display 30a. The first display 20a and the second display 30a are respectively disposed on two sides of the middle frame 10a, and both the first display 20a and the second display 30a can be used to display an image. The mobile phone further includes electronic elements such as a mainboard 40a and a speaker 90a. The mainboard 40a and the speaker 90a are located between the first display 20a and the second display 30a, and the mainboard 40a and the speaker 90a are disposed side by side along a length direction of the mobile phone. A surface that is of the first display 20a and that faces the mainboard 40a is connected to a flexible printed circuit board 21a, and the flexible printed circuit board 21a is wound from a side that is of the mainboard 40a and that faces the first display 20a, from between the mainboard 40a and the speaker 90a, to a side that is of the mainboard 40a and that is away from the first display 20a, and is electrically connected to a surface that is of the mainboard 40a and that faces the second display 30a. In addition, the second display 30a is also electrically connected to the surface that is of the mainboard 40a and that faces the second display 30a. That is, the first display 20a and the second display 30a are electrically connected to a same surface of the mainboard 40a, and the flexible printed circuit board 21a surrounds a part of the mainboard 40a from a side of the mainboard 40a.

A mounting process of the dual screen mobile phone is as follows: The first display 20a is mounted on a side of the middle frame 10a, and then the mainboard 40a is mounted on a side that is of the first display 20a and that faces the middle frame 10a, so that the flexible printed circuit board 21a on the first display 20a is wound around a side that is of the mainboard 40a and that is away from the first display 20a for connection, and the speaker 90a is mounted on a side that is of the first display 20a and that faces the middle frame 10a, and then a second display 30a is mounted on the other side of the middle frame 10a.

However, when the first display 20a of the foregoing dual screen mobile phone is faulty and needs to be repaired or replaced, the second display 30a and the speaker 90a first need to be sequentially detached, and then a connection relationship between the mainboard 40a and the flexible printed circuit board 21a needs to be released, and the mainboard 40a needs to be detached, and then the first display 20a needs to be detached. In general, in the related technology, components located on a side that is of the first display 20a and that faces the middle frame 10a need to be detached from the dual screen mobile phone before the first display 20a can be removed. In this way, a detachment process is cumbersome; in addition, in the detachment process, electronic elements such as the second display 30a, the mainboard 40a, and the speaker 90a may be easily scraped or damaged because of a collision, and consequently, electronic elements such as the second display 30a, the mainboard 40a, and the speaker 90a also need to be replaced, and repair costs are high, and when the electronic elements are assembled after repair, precision of cooperation between the electronic elements cannot be easily ensured.

After careful research, researchers have found that a main reason for a complex detachment process in the related technology is that, when the flexible printed circuit board on the first display is wound around two sides of the mainboard and directly pulls the first display along a direction away from the mainboard, the flexible printed circuit board drives the mainboard to move, and a mounting position of the mainboard and a connection relationship between the mainboard and the second display are affected. Therefore, components that are located on a side that is of the first display and that faces the middle frame need to be detached before the first display can be removed. Based on this, the researchers have thought that both the first display and the second display are designed to be connected to a surface that is opposite to the mainboard, so that no flexible printed circuit board is wound around two sides of the mainboard. In this way, when the electronic elements such as the mainboard, the speaker, and the second display are not detached, the first display can be moved directly along a direction away from the mainboard, so that the first display can be directly detached, a detachment process is simplified, and the electronic elements such as the mainboard and the second display can be prevented from being damaged during detachment. The following describes in detail an implementation of an electronic device provided in this embodiment of this application.

<FIG> and <FIG> schematically show a structure of a foldable dual screen mobile phone in an unfolded state. Referring to <FIG> and <FIG>, an embodiment of this application provides an electronic device <NUM> with two screens, which may include, but is not limited to, a foldable fixed terminal or mobile terminal such as a mobile phone, a tablet computer, a notebook computer, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a handheld computer, a touch TV, a walkie-talkie, a netbook, a POS terminal, a personal digital assistant (personal digital assistant, PDA), a wearable device, or a virtual reality device. In this embodiment of this application, an example in which the electronic device <NUM> is a mobile phone is used for description. The electronic device <NUM> includes a middle frame <NUM>, a first display <NUM>, and a second display <NUM>. The middle frame <NUM> is configured to carry the first display <NUM> and the second display <NUM>. The middle frame <NUM> includes a middle plate <NUM> (as shown in the following <FIG>) and a frame <NUM> (as shown in the following <FIG>), and the frame <NUM> is connected to an entire circumferential edge of the middle plate <NUM>. The middle plate <NUM> may be a metal middle plate <NUM> made of a metal material such as aluminum or magnesium. The first display <NUM> and the second display <NUM> are respectively disposed on two sides of the metal middle plate <NUM>, and are connected to the metal middle plate <NUM> in a manner such as bonding.

Each of the first display <NUM> and the second display <NUM> may be an organic light-emitting diode (Organic Light-Emitting Diode, OLED) display or a liquid crystal display (Liquid Crystal Display, LCD). Alternatively, in some embodiments, one of the first display <NUM> and the second display <NUM> may be the OLED display or the LCD, the other of the first display <NUM> and the second display <NUM> may be an E-Ink ink screen, the OLED display or the LCD has high resolution, and the E-Ink ink screen has low reflectivity. Therefore, the user may use the OLED display or the LCD to view an image and read by using the E-Ink ink screen, to avoid damage to eyesight due to use of the OLED display or the LCD for reading for a long time.

Sizes of the first display <NUM> and the second display <NUM> may be the same or may be different. For example, a size of the second display <NUM> may be smaller than a size of the first display <NUM>, and the first display <NUM> and the second display <NUM> can switch to display, to implement switching of the size of the screen. In this way, when the power of the electronic device <NUM> is relatively low, the user may use the second display <NUM> to reduce power consumption of the electronic device <NUM>.

The first display <NUM> and the second display <NUM> each may be a flexible display that can be folded, and the middle frame <NUM> may also be folded, so that the electronic device <NUM> can be folded. <FIG> schematically shows a structure of a foldable mobile phone in a semi-folded state. As shown in <FIG>, the middle frame <NUM> includes a first structural member <NUM>, a second structural member <NUM>, and a rotating assembly <NUM> disposed between the first structural member <NUM> and the second structural member <NUM>. Both the first structural member <NUM> and the second structural member <NUM> are rotatably connected to the rotating assembly <NUM>, so that the first structural member <NUM> and the second structural member <NUM> can rotate relative to the rotating assembly <NUM>. In this embodiment of this application, the first structural member <NUM> may be a first middle frame, and the second structural member <NUM> may be a second middle frame. Therefore, the first structural member <NUM> and the second structural member <NUM> each may include a middle plate <NUM> and a frame <NUM>.

<FIG> schematically shows a structure of a foldable mobile phone in a folded state. In the example shown in <FIG>, the first display <NUM> is a flexible display, a size of the second display <NUM> is smaller than that of the first display <NUM>, and the first structural member <NUM> and the second structural member <NUM> can rotate toward each other to be stacked on each other. In this case, the first display <NUM> can be bent and attached between the first structural member <NUM> and the second structural member <NUM>, the second display <NUM> is exposed outside to display an image, and the mobile phone is in a folded state (for example, as shown in <FIG>). The first structural member <NUM> and the second structural member <NUM> may further rotate away from each other from a stacked state to a state in which the first structural member <NUM> and the second structural member <NUM> are on a same plane. In this case, the first display <NUM> unfolds, and the mobile phone is in an unfolded state (for example, as shown in <FIG>).

With reference to the foregoing description, it may be learned that the dual screen electronic device <NUM> provided in this embodiment may be an electronic device <NUM> that cannot be folded, or may be an electronic device <NUM> that can be folded.

<FIG> schematically shows a breakdown structure of an electronic device <NUM> according to an embodiment. Referring to <FIG>, the electronic device <NUM> further includes a mainboard <NUM>. The mainboard <NUM> is mounted on the middle plate <NUM>, and is disposed in parallel with the first display <NUM> and the second display <NUM>. The mainboard <NUM> may be disposed on a side that is of the middle plate <NUM> and that faces the first display <NUM>, or may be disposed on a side that is of the middle plate <NUM> and that faces the second display <NUM>. The mainboard <NUM> may be a circuit board made of a flexible material, or may be a rigid printed circuit board (Printed Circuit Board; PCB). An electronic element <NUM> is disposed on the mainboard <NUM>, and the electronic element <NUM> may be any one or more of a power amplifier, a central processing unit (Central Processing Unit; CPU), a power management integrated circuit (Power Management IC; PMIC), a universal flash storage (Universal Flash Storage; UFS), and an image signal processor (Image Signal Processor; ISP).

The mainboard <NUM> is a double-sided board. The mainboard <NUM> has a first surface <NUM> and a second surface <NUM> that are disposed facing away from each other, and electronic elements <NUM> may be disposed on both the first surface <NUM> and the second surface <NUM>. The first surface <NUM> refers to a surface that is of the mainboard <NUM> and that faces the first display <NUM>. On the contrary, the second surface <NUM> refers to a surface that is of the mainboard <NUM> and that faces the second display <NUM>. The mainboard <NUM> is electrically connected to both the first display <NUM> and the second display <NUM>, to supply power to the first display <NUM> and the second display <NUM>. A specific implementation is as follows: A first flexible printed circuit board <NUM> is disposed on a non-display surface of the first display <NUM>, and the other end that is of the first flexible printed circuit board <NUM> and that is away from the first display <NUM> extends between the first display <NUM> and the mainboard <NUM>, and is electrically connected to the first surface <NUM> of the mainboard <NUM>; and a second flexible printed circuit board <NUM> is disposed on a non-display surface of the second display <NUM>, and the other end that is of the second flexible printed circuit board <NUM> and that is away from the second display <NUM> extends between the second display <NUM> and the mainboard <NUM>, and is electrically connected to the second surface <NUM> of the mainboard <NUM>. The non-display surface of the first display <NUM> refers to a surface that is of the first display <NUM> and that faces the mainboard <NUM> and that is away from the outside, and the non-display surface of the second display <NUM> refers to a surface that is of the second display <NUM> and that faces the mainboard <NUM> and that faces the outside. The first flexible printed circuit board <NUM> and the second flexible printed circuit board <NUM> each is a printed circuit board made of a flexible insulation material, has relatively high flexibility, and can be freely bent, wound, and folded, so that the first flexible printed circuit board <NUM> can be bent and extend between the first display <NUM> and the mainboard <NUM>, and the second flexible printed circuit board <NUM> can be bent and extend between the second display <NUM> and the mainboard <NUM>.

<FIG> schematically shows a three-dimensional structure of a middle frame <NUM>. It should be noted that, as shown in <FIG>, an opening <NUM> is disposed on the middle plate <NUM>, and a part of the mainboard <NUM> directly faces the opening <NUM>, to ensure that the first flexible printed circuit board <NUM> and the second flexible printed circuit board <NUM> that are located on two sides of the middle plate <NUM> can be connected to the mainboard <NUM>. Specifically, when the mainboard <NUM> is disposed on a side that is of the middle plate <NUM> and that faces the first display <NUM>, the second flexible printed circuit board <NUM> can extend into the opening <NUM> to connect the second surface <NUM> of the mainboard <NUM>. Similarly, referring to <FIG> and <FIG>, when the mainboard <NUM> is disposed on a side that is of the middle plate <NUM> and that faces the second display <NUM>, the first flexible printed circuit board <NUM> can extend into the opening <NUM> to connect the first surface <NUM> of the mainboard <NUM>. <FIG> schematically shows a schematic sectional view of an electronic device <NUM> taken along a direction L-L in <FIG>; and <FIG> schematically shows a schematic sectional view of a breakdown structure of an electronic device <NUM> taken along a direction L-L in <FIG>. A shape of the opening <NUM> is not limited. The opening <NUM> may be in a regular shape such as a circular shape, a square, a rectangle, or a rounded rectangle, or may be in another irregular shape.

It may be learned from the foregoing description that, in this embodiment, both the first flexible printed circuit board <NUM> and the second flexible printed circuit board <NUM> of the electronic device <NUM> are connected to a surface that is opposite to the mainboard <NUM>, and neither of the first flexible printed circuit board <NUM> and the second flexible printed circuit board <NUM> is wound around two sides of the mainboard <NUM>. In this way, when the first display <NUM> needs to be repaired or replaced due to crack, scraping, poor contact, or another reason, an example of the detachment process of the first display <NUM> may be as follows: A connection relationship between the first display <NUM> and the middle frame <NUM> is released, the first display <NUM> is moved in a positive direction (a direction shown by a solid arrow in <FIG>) of the electronic device <NUM> to move away from the mainboard <NUM>, the first flexible printed circuit board <NUM> extends with movement of the first display <NUM>; and a connection relationship between the flexible printed circuit board <NUM> and the mainboard <NUM> is released, so that the first display <NUM> is detached from the mainboard <NUM>. The positive direction of the electronic device <NUM> refers to a direction that is of the first display <NUM> and that faces the user when the electronic device <NUM> is in an unfolded state. On the contrary, a reverse direction of the electronic device <NUM> (a direction shown by a dashed arrow in <FIG>) refers to a direction that is of the second display <NUM> and that faces the user when the electronic device <NUM> is in an unfolded state. On the contrary, after repair of the first display <NUM> is completed, a process of reassembling the first display <NUM> on the middle frame <NUM> is as follows: The first display <NUM> is moved to a side of the middle frame <NUM>, the first flexible printed circuit board <NUM> is connected to the first surface <NUM> of the mainboard <NUM>, and then the first display <NUM> is connected to the middle frame <NUM>.

It may be understood that no second flexible printed circuit board <NUM> is wound around two sides of the mainboard <NUM>. Therefore, when the second display <NUM> needs to be repaired or replaced due to crack, scraping, poor contact, or another reason, the second display <NUM> can be directly detached from the reverse direction of the electronic device <NUM>. Certainly, for the electronic device <NUM> provided in this embodiment, first, the second display <NUM> and the mainboard <NUM> may be sequentially detached and then the first display <NUM> is detached.

In conclusion, for the electronic device <NUM> provided in this embodiment, the first display <NUM> can be directly detached from the positive direction of the electronic device <NUM>. In this way, when the first display <NUM> is faulty and needs to be replaced or repaired, if the first display <NUM> is directly detached from a positive direction of the electronic device <NUM>, components such as the second display <NUM> and the mainboard <NUM> do not need to be detached, and a detachment process is simple; in addition, this prevents electronic elements such as the mainboard <NUM> and the second display <NUM> from being damaged due to collision or scraping in the detachment process, thereby avoiding high repair costs. In addition, after repair of the first display <NUM> is completed, only the first display <NUM> needs to be reassembled, and the mainboard <NUM> and the second display <NUM> do not need to be reassembled, and a reassembly process is simple. In addition, because only a few components need to be reassembled, this reduces a possibility that mounting precision between reassembled components is reduced, and there is no need to comprehensively detect a function of the reassembled electronic device <NUM>.

<FIG> schematically shows a three-dimensional structure of the first flexible printed circuit board <NUM>. In the foregoing embodiment, the first flexible printed circuit board <NUM> may include at least a bent segment <NUM> and a connection segment <NUM> that are connected. One end that is of the bent segment <NUM> and that is away from the connection segment <NUM> is connected to a non-display surface of the first display <NUM>, the connection segment <NUM> extends between the first display <NUM> and the mainboard <NUM>, and the connection segment <NUM> is connected to the first surface <NUM> of the mainboard <NUM>. The bent segment <NUM> and a surface that is of the first display <NUM> and that faces the mainboard <NUM> may be connected in a bonding manner. A bent shape of the bent segment <NUM> is not limited. For example, the bent segment <NUM> may have a bent angle (not shown in the figure), that is, the bent segment <NUM> is in a bent line shape, or in the example shown in <FIG>, the bent segment <NUM> may also be arc-shaped, and the bent segment <NUM> in the arc shape does not have a sharp angle, so as to avoid stress concentration at the bent angle of the bent segment <NUM>. It may be understood that at least one bend may be formed on the bent segment <NUM>. That is, in some embodiments, the bent segment <NUM> may have a plurality of bends, and bent shapes and bent angles of the plurality of bends may be the same or different.

It should be noted herein that because the first flexible printed circuit board <NUM> has a bent segment <NUM>, the bent segment <NUM> can be bent and extend, so that a redundant part is formed on the first flexible printed circuit board <NUM>, and the redundant part can extend and be bent. Therefore, in a process of detaching the first display <NUM>, when the first display <NUM> is moved in a positive direction of the electronic device <NUM> to move away from the mainboard <NUM>, the bent segment <NUM> can extend with movement of the first display <NUM>, so that a pulling force of the first display <NUM> on the first flexible printed circuit board <NUM> directly acts on a connection point between the connection segment <NUM> and the mainboard <NUM>, thereby preventing the mainboard <NUM> from being pulled when the first display <NUM> is detached.

A structure of the second flexible printed circuit board <NUM> may be the same as a structure of the first flexible printed circuit board <NUM>. That is, for the structure of the second flexible printed circuit board <NUM>, refer to the structure of the first flexible printed circuit board <NUM>. In <FIG> and <FIG>, the second flexible printed circuit board <NUM> may also include a mounting segment <NUM> and a bent segment <NUM> that are connected. One end that is of the bent segment <NUM> and that is away from the mounting segment <NUM> is connected to a non-display surface of the second display <NUM>, and one end that is of the mounting segment <NUM> and that is away from the bent segment <NUM> is connected to a second surface <NUM> of the mainboard <NUM>. Therefore, when the second display <NUM> is detached, a redundant part of the second flexible printed circuit board <NUM> can extend, to prevent the mainboard <NUM> from being pulled by the second flexible printed circuit board <NUM> when the second display <NUM> is detached.

In some embodiments, as shown in <FIG>, the first flexible printed circuit board <NUM> may further include a fastening segment <NUM>, where the fastening segment <NUM> is fastened to a non-display surface of the first display <NUM>, and the fastening segment <NUM> is connected to one end that is of the bent segment <NUM> and that is away from the connection segment <NUM>. By disposing the fastening segment <NUM>, a connection portion between the first flexible printed circuit board <NUM> and the first display <NUM> is added, so that the first flexible printed circuit board <NUM> can be mounted more reliably. The fastening segment <NUM> may be configured to extend along any direction, provided that the fastening segment <NUM> can be connected to one end of the bent segment <NUM>. For example, the fastening segment <NUM> may extend along a length direction of the electronic device <NUM> to connect the mainboard <NUM>, or the fastening segment <NUM> may extend along a width direction of the electronic device <NUM> to connect the mainboard <NUM>. The fastening segment <NUM> and the connection segment <NUM> may be located on a same side of the bent segment <NUM>, or the fastening segment <NUM> and the connection segment <NUM> may be respectively disposed on two sides of the bent segment <NUM>.

As shown in <FIG> and <FIG>, the electronic device <NUM> may further include a functional component <NUM>. The functional component <NUM> is mounted on the middle plate <NUM>, the functional component <NUM> and the mainboard <NUM> are disposed on a same side of the middle plate <NUM>, and the functional component <NUM> and the mainboard <NUM> are disposed side by side along the length direction of the electronic device <NUM>. The functional component <NUM> may be a speaker, and the electronic device <NUM> has a sound generation function. Alternatively, the functional component <NUM> may be a camera, and the electronic device <NUM> has a photographing function. In a process of assembling the electronic device <NUM>, there may be no mounting sequence between the functional component <NUM> and the mainboard <NUM>. The functional component <NUM> may be mounted on the middle plate <NUM> after the mainboard <NUM> is mounted on the middle plate <NUM>; or the functional component <NUM> may be mounted on the middle plate <NUM> before the mainboard <NUM> is mounted on the middle plate <NUM>.

A thickness of the middle plate <NUM> may be the same everywhere, or thicknesses of at least two positions of the middle plate <NUM> may be different. In the example shown in <FIG>, thicknesses of all parts of the middle plate <NUM> are not completely the same, so that a first recess <NUM> is formed on the middle plate <NUM>. Both the mainboard <NUM> and the functional component <NUM> are mounted in the first recess <NUM>, and a projection of the first recess <NUM> on the middle plate <NUM> is slightly larger than projections of the mainboard <NUM> and the functional component <NUM> on the middle plate <NUM>, so that a size of the first recess <NUM> can match sizes of the mainboard <NUM> and the functional component <NUM> that are disposed side by side. Therefore, mounting positions of the mainboard <NUM> and the functional component <NUM> can be identified accurately.

When the mainboard <NUM> and the first display <NUM> are disposed on a same surface that is of the middle plate <NUM>, a first recess <NUM> is formed on a surface that is of the middle plate <NUM> and that faces the first display <NUM>, and the functional component <NUM> is correspondingly disposed on a side that is of the middle plate <NUM> and that faces the first display <NUM>. In this embodiment, the opening <NUM> may be aligned with only a part that is of the mainboard <NUM> and that is connected to the first flexible printed circuit board <NUM>, to reduce a size of the opening <NUM> as much as possible, thereby ensuring that the middle frame <NUM> has relatively high strength to stably carry the mainboard <NUM> and the functional component <NUM>.

When the mainboard <NUM> and the second display <NUM> are disposed on a same side of the middle plate <NUM>, a first recess <NUM> is formed on a surface that is of the middle plate <NUM> and that faces the second display <NUM>, and the functional component <NUM> is correspondingly disposed on a side that is of the middle plate <NUM> and that faces the second display <NUM>. In this embodiment, as shown in <FIG> and <FIG>, the opening <NUM> may alternatively be aligned with the functional component <NUM>. In this case, a protruding portion <NUM> may protrude from a surface that is of the functional component <NUM> and that faces the first display <NUM>, and the protruding portion <NUM> may extend from the opening <NUM> to a side that is of the middle plate <NUM> and that faces the first display <NUM>, and the first display <NUM> can directly or indirectly support the protruding portion <NUM> to provide support for the functional component <NUM>. In this example, if the opening <NUM> is a rectangle or a rounded rectangle, and the opening <NUM> extends along a length direction of the electronic device <NUM>, compared with the circular opening <NUM>, the opening <NUM> can be as small as possible while being aligned with the functional component <NUM> and the mainboard <NUM>, thereby ensuring that the middle frame <NUM> has a relatively high strength to stably carry the mainboard <NUM> and the functional component <NUM>. It may be understood that, when the opening <NUM> is aligned with both the mainboard <NUM> and the functional component <NUM>, the connection segment <NUM> of the first flexible printed circuit board <NUM> may completely face the opening <NUM>.

Regardless of whether the mainboard <NUM> and the functional component <NUM> are disposed on a side that is of the mainboard <NUM> and that faces the first display <NUM> or a side that is of the mainboard <NUM> and that is away from the first display <NUM>, a positional relationship between the first flexible printed circuit board <NUM> and the first display <NUM> and the mainboard <NUM> may be as follows:
In a first case, as shown in <FIG>, the entire first flexible printed circuit board <NUM> may be disposed between the first display <NUM> and the mainboard <NUM>. <FIG> schematically shows another cross-sectional structure of an electronic device <NUM> along a direction L-L in <FIG>. In this case, if the first flexible printed circuit board <NUM> includes only the connection segment <NUM> and the bent segment <NUM>, both the connection segment <NUM> and the bent segment <NUM> are located between the first display <NUM> and the mainboard <NUM>. If the first flexible printed circuit board <NUM> further includes a fastening segment <NUM>, the connection segment <NUM>, the bent segment <NUM>, and the fastening segment <NUM> are all located between the first display <NUM> and the mainboard <NUM>. In this case, the functional component <NUM> may be in direct contact with a non-display surface of the first display <NUM>, and the functional component <NUM> and the first display <NUM> support each other.

In a second case, as shown in <FIG>, when the first flexible printed circuit board <NUM> further includes a fastening segment <NUM>, and the fastening segment <NUM> and the connection segment <NUM> are located on different sides of the bent segment <NUM>, the connection segment <NUM> and the bent segment <NUM> may be located between the first display <NUM> and the mainboard <NUM>, and the fastening segment <NUM> may extend between the functional component <NUM> and the first display <NUM>. In this case, the functional component <NUM> may abut on a surface that is of the fastening segment <NUM> and that faces the mainboard <NUM>. <FIG> schematically shows still another cross-sectional structure of an electronic device <NUM> along a direction L-L in <FIG>.

In a third case, as shown in <FIG>, parts of the bent segment <NUM> and the connection segment <NUM> are disposed between the functional component <NUM> and the first display <NUM>, and the other part of the connection segment <NUM> is disposed between the first display <NUM> and the mainboard <NUM>. In this way, the first flexible printed circuit board <NUM> is not limited between the mainboard <NUM> and the first display <NUM>, and can extend in a larger space.

In this example, when the first flexible printed circuit board <NUM> further includes a fastening segment <NUM>, if the fastening segment <NUM> and the connection segment <NUM> are located on different sides of the bent segment <NUM>, the fastening segment <NUM> may extend between the functional component <NUM> and the first display <NUM>. Referring to <FIG>, if the fastening segment <NUM> and the connection segment <NUM> are located on a same side of the bent segment <NUM>, a part of the fastening segment <NUM> may be located between the mainboard <NUM> and the first display <NUM>, and the other part of the fastening segment <NUM> may be located between the functional component <NUM> and the first display <NUM>.

A part of the functional component <NUM> may be further configured to be jointly enclosed, with the first display <NUM>, into an avoidance groove <NUM> for accommodating the bent segment <NUM>, to prevent interference between the bent segment <NUM> and the functional component <NUM>. In the example shown in <FIG>, the functional component <NUM> is provided with a protruding portion <NUM>. A surface that is of the functional component <NUM> and that faces the first display <NUM> and the protruding portion <NUM> may jointly define a step surface. The step surface and the first display <NUM> are jointly enclosed into an avoidance groove <NUM>, and the avoidance groove <NUM> is formed on the other side that is of the protruding portion <NUM> and that is away from the mainboard <NUM>. In this case, the connection segment <NUM> extends between the mainboard <NUM> and the first display <NUM>, from the protruding portion <NUM> and the first display <NUM>, and the protruding portion <NUM> of the functional component <NUM> abuts on a surface that is of the connection segment <NUM> and that is away from the first display <NUM>. In addition, if the first flexible printed circuit board <NUM> further includes a fastening segment <NUM>, and the fastening segment <NUM> and the connection segment <NUM> are located on a same side of the bent segment <NUM>, the fastening segment <NUM> is connected to a non-display surface of the first display <NUM>, and the connection segment <NUM> and the fastening segment <NUM> are sandwiched between the functional component <NUM> and the first display <NUM>.

Certainly, in another embodiment, the avoidance groove <NUM> may alternatively be disposed on a side that is of the functional component <NUM> and that is close to the mainboard <NUM>, so that the avoidance groove <NUM> can be connected to a space between the mainboard <NUM> and the first display <NUM>. In this case, the functional component <NUM> may be directly in contact with a non-display surface of the first display <NUM>.

<FIG> schematically shows a three-dimensional structure of a locking bracket <NUM>. In some examples of this application, referring to <FIG> and <FIG>, the electronic device <NUM> may further include a locking bracket <NUM>, where the locking bracket <NUM> is disposed between the mainboard <NUM> and the first display <NUM>, the locking bracket <NUM> is detachably connected to the middle frame <NUM>, and is in contact with a surface that is of the connection segment <NUM> and that is away from the mainboard <NUM>. In this way, the locking bracket <NUM> can press the connection segment <NUM>, to prevent the first flexible printed circuit board <NUM> from loosening from the mainboard <NUM>.

An extension direction of the locking bracket <NUM> is perpendicular to an extension direction of the connection segment <NUM>, so that the connection segment <NUM> can be attached to the locking bracket <NUM>, and then can be pressed by the fastened bracket <NUM>. <FIG> schematically shows breakdown structures of a locking bracket <NUM> and a middle frame <NUM>. Referring to <FIG> and <FIG>, an example in which the opening <NUM> is a rectangle is used for description. The rectangular opening <NUM> extends along a length direction of the electronic device <NUM>. Correspondingly, the locking bracket <NUM> may extend along a width direction of the electronic device <NUM>, and two ends of the locking bracket <NUM> extend to two sides of the opening <NUM>, so that the locking bracket <NUM> crosses the opening <NUM>, and a part of the locking bracket <NUM> can face the opening <NUM>, and then the locking bracket <NUM> can face a part that is of the mainboard <NUM> and that is connected to the first flexible printed circuit board <NUM>. In this design, one end that is of the connection segment <NUM> and that is away from the bent segment <NUM> may extend to the opening <NUM>, and may be inserted between the mainboard <NUM> and the locking bracket <NUM>.

For example, the first flexible printed circuit board <NUM> may be connected to the mainboard <NUM> by using the connector <NUM>. The connector <NUM> may be, for example, a board-to-board connector <NUM> (board to board; BTB). The connector <NUM> includes a male socket <NUM> and a female socket <NUM> (as shown in the following <FIG>). The male socket <NUM> is disposed on a non-display surface of the first flexible printed circuit board <NUM>, the female socket <NUM> is disposed on a first surface <NUM> of the mainboard <NUM>, and the female socket <NUM> may be inserted into the male socket <NUM>, so that the first flexible printed circuit board <NUM> is electrically connected to the mainboard <NUM>. Specifically, a clamping gap may be defined between the locking bracket <NUM> and the mainboard <NUM>, and the first flexible printed circuit board <NUM>, the male socket <NUM>, and the female socket <NUM> are clamped in the clamping gap. In this way, a joint between the first flexible printed circuit board <NUM> and the mainboard <NUM> may be clamped in the clamping gap, to prevent the male socket <NUM> of the connector <NUM> from being separated from the female socket <NUM>, so that a connection between the first flexible printed circuit board <NUM> and the mainboard <NUM> is more reliable.

Herein, when the mainboard <NUM> and the second display <NUM> are located on a same side, the locking bracket <NUM> may be connected to a surface that is of the middle plate <NUM> and that faces the first display <NUM>, so that the locking bracket <NUM> is located on a side that is of the middle plate <NUM> and that faces the first display <NUM>.

Alternatively, as shown in <FIG>, a first mounting base <NUM> and a second mounting base <NUM> protrude from a surface that is of the middle plate <NUM> and that faces the second display <NUM>, and projections of the first mounting base <NUM> and the second mounting base <NUM> on the middle plate <NUM> are located in the opening <NUM>. In addition, the locking bracket <NUM> may be accommodated in the opening <NUM>, and two ends of the locking bracket <NUM> are detachably connected to the first mounting base <NUM> and the second mounting base <NUM>, respectively. Therefore, compared with a manner in which the locking bracket <NUM> is connected to the surface that is of the middle plate <NUM> and that faces the first display <NUM>, the locking bracket <NUM> in this embodiment can mounted in the opening <NUM>, to avoid a relatively large gap between the first display <NUM> and the middle plate <NUM> because the locking bracket <NUM> protrudes from the surface of the middle plate <NUM>, thereby improving utilization of the space. The first mounting base <NUM> may be a plate-like structure, or may be a block-like structure. This is not limited in this embodiment.

The locking bracket <NUM> may be a flat plate-like structure. Alternatively, as shown in <FIG>, the locking bracket <NUM> may include a first plate body <NUM>, a second plate body <NUM>, and a middle plate body <NUM> located between the first plate body <NUM> and the second plate body <NUM>. Two ends of the middle plate body <NUM> are respectively connected to the first plate body <NUM> and the second plate body <NUM>, and a surface of the middle plate body <NUM> is different from surfaces of the first plate body <NUM> and the second plate body <NUM>, so that a groove is formed on a surface that is of the locking bracket <NUM> and that faces the mainboard <NUM>. In this way, on a basis that the locking bracket <NUM> is mounted in the opening <NUM>, a clamping gap can be enlarged as much as possible, so that the connector <NUM> and the connection segment <NUM> can be clamped in the clamping gap.

With reference to the foregoing description, it is easy to understand that when the mainboard <NUM> and the first display <NUM> are located on a same side, the first mounting base <NUM> and the second mounting base <NUM> protrude from a surface that is of the middle plate <NUM> and that faces the first display <NUM>, and two ends of the locking bracket <NUM> are connected to the first mounting base <NUM> and the second mounting base <NUM>.

In some embodiments, each of the first mounting base <NUM> and the second mounting base <NUM>, and the middle plate <NUM> may form an integrated component by using an integrated molding process. Therefore, steps of assembling the first mounting base <NUM> and the second mounting base <NUM> may be omitted, thereby improving assembly efficiency. In addition, strength of the middle plate <NUM> may be improved without increasing costs.

A manner of detachable connection between the locking bracket <NUM> and the middle frame <NUM> is not limited to a screw connection, or may be a connection manner such as clamping. Referring to <FIG>, <FIG>, for example, a screw hole <NUM> is disposed on each of the first mounting base <NUM> and the second mounting base <NUM>, and through holes <NUM> are disposed on two ends of the locking bracket <NUM>. A screw hole <NUM> of the first mounting base <NUM> is coaxial with a through hole <NUM> of one end of the locking bracket <NUM>, and a screw hole <NUM> of the second mounting base <NUM> is coaxial with a through hole <NUM> of the other end of the locking bracket <NUM>. A screw may be connected to the screw hole <NUM> after passing through the through hole <NUM>, so that the locking bracket <NUM> is connected to the first mounting base <NUM> by using the screw.

Alternatively, the second flexible printed circuit board <NUM> may be electrically connected to the second surface <NUM> of the mainboard <NUM> by using the connector <NUM>. Specifically, a female socket <NUM> is disposed on the second surface <NUM> of the mainboard <NUM>, and a male socket <NUM> that can be inserted into the female socket <NUM> is disposed on a surface that is of the second flexible printed circuit board <NUM> and that faces the mainboard <NUM>, so that the second flexible printed circuit board <NUM> is electrically connected to the mainboard <NUM>.

Still referring to <FIG>, <FIG>, <FIG>, when the mainboard <NUM> and the second display <NUM> are disposed on a same side of the middle plate <NUM>, the electronic device <NUM> may further include a cover plate <NUM>, where the cover plate <NUM> is disposed between the mainboard <NUM> and the second display <NUM>, and the cover plate <NUM> presses the second surface <NUM> of the mainboard <NUM>. With such arrangement, the cover plate <NUM> can prevent the mainboard <NUM> from abutting on the second display <NUM>, to ensure that the second display <NUM> and the middle frame <NUM> are reliably connected. In addition, the cover <NUM> can press a joint between the second display <NUM> and the mainboard <NUM>, to prevent loosening of the connector <NUM> between the second display <NUM> and the mainboard <NUM>, so that a connection between the second flexible printed circuit board <NUM> and the mainboard <NUM> is more reliable. It should be noted that, in this embodiment, referring to the following <FIG> and <FIG>, the mounting segment <NUM> of the second flexible printed circuit board <NUM> can extend from a gap between the frame <NUM> and the cover plate <NUM> into the mainboard <NUM> and the cover plate <NUM>, to connect the mainboard <NUM>. In this case, the second flexible printed circuit board <NUM> surrounds an edge of a side of the cover plate <NUM>. In an alternative embodiment, a via hole (not shown in the figure) may further be disposed on the cover plate <NUM>, and a mounting segment <NUM> of the second flexible printed circuit board <NUM> may extend between the mainboard <NUM> and the cover plate <NUM> through the via hole.

Referring to <FIG>, <FIG>, and <FIG>, on the basis of any one of the foregoing embodiments, the electronic device <NUM> may further include a rear cover <NUM>, and the rear cover <NUM> is disposed on a side that is of the middle plate <NUM> and that faces the second display <NUM>. When the electronic device <NUM> cannot be folded, the rear cover <NUM> may be mounted on the other side of the middle frame <NUM>, and the second display <NUM> may be mounted on the rear cover <NUM>. In this case, a size of the second display <NUM> may be smaller than a size of the first display <NUM>. When the electronic device <NUM> can be folded, the middle frame <NUM> may include, for example, a first structural member <NUM> and a second structural member <NUM>, and the second display <NUM> and the rear cover <NUM> may be mounted on the first structural member <NUM> and the second structural member <NUM>, respectively. When the electronic device <NUM> is in an unfolded state, the first structural member <NUM> and the second structural member <NUM> can rotate to a same plane, and correspondingly, the rear cover <NUM> and the second display <NUM> are also located on a same plane.

As shown in <FIG> and <FIG>, the electronic device <NUM> may further include a battery <NUM>. The battery <NUM> and the mainboard <NUM> are disposed on a same side of the middle plate <NUM>, and the battery <NUM> is electrically connected to the mainboard <NUM> to supply power to the mainboard <NUM>. In <FIG>, thicknesses of all parts of the middle plate <NUM> are not completely the same, so that a first recess <NUM> is formed on the middle plate <NUM>, and a second recess <NUM> is also formed on the middle plate <NUM>, where the battery <NUM> is mounted in the second recess <NUM>. When the middle frame <NUM> includes the first structural member <NUM> and the second structural member <NUM>, the second recess <NUM> may be formed on the first structural member <NUM>. Correspondingly, similar to the mainboard <NUM>, the battery <NUM> is also disposed between the second display <NUM> and the first display <NUM>. Alternatively, the second recess <NUM> may be formed on the second structural member <NUM>. Correspondingly, the battery <NUM> is disposed between the first display <NUM> and the rear cover <NUM>. In this case, the rear cover <NUM> may also be referred to as a cover of the battery <NUM>.

<FIG> schematically show a detachment process of a first display <NUM> of an electronic device <NUM>. In the foregoing embodiment, when the first display <NUM> needs to be repaired or replaced due to crack, scraping, poor contact, or another reason, another example of the detachment process of the first display <NUM> may be as follows:
As shown in <FIG>, the electronic device <NUM> is first provided, and the first display <NUM> faces a direction in which the user is located, to facilitate subsequent detachment.

As shown in <FIG>, a connection relationship between the first display <NUM> and the middle frame <NUM> is released, and the first display <NUM> is moved in a positive direction of the electronic device <NUM> to move away from the mainboard <NUM>. In this process, the first flexible printed circuit board <NUM> has a redundant part, and the redundant part can extend with movement of the first display <NUM>, to alleviate a pulling force on the first flexible printed circuit board <NUM>, thereby preventing the mainboard <NUM> from being pulled.

As shown in <FIG>, screws connecting the locking bracket <NUM> to both the first mounting base <NUM> and the second mounting base <NUM> are tightened, so that the locking bracket <NUM> is detached.

As shown in <FIG>, a force is exerted on the connection segment <NUM> of the first flexible printed circuit board <NUM>, so that the male socket <NUM> of the connector <NUM> is released from the female socket <NUM>, and then the first flexible printed circuit board <NUM> is disengaged from the mainboard <NUM>, so that the first display <NUM> is detached.

It may be understood that, after repair of the first display <NUM> is completed, an assembly sequence of a reassembly process of the first display <NUM> may be reverse to a detachment process of the first display <NUM>. Specifically, an example of the reassembly process of the first display <NUM> is as follows: First, the male socket <NUM> on the first flexible printed circuit board <NUM> is buckled with the female socket <NUM> on the mainboard <NUM>, and the male socket <NUM> and the female socket <NUM> jointly form the connector <NUM>, so that the first flexible printed circuit board <NUM> is connected to the mainboard <NUM>; then the locking bracket <NUM> is detachably connected to the middle frame <NUM>, so that a joint between the first flexible printed circuit board <NUM> and the mainboard <NUM> is pressed by the locking bracket <NUM>; then the first display <NUM> is moved to make the first display <NUM> opposite to the middle plate <NUM>; and then the first display <NUM> is connected to the middle plate <NUM>, to complete reassembly of the first display <NUM>.

The following describes an assembly process of an electronic device <NUM> provided in embodiments of this application.

<FIG> schematically show an assembly process of an electronic device <NUM>. An example in which the mainboard <NUM> and the second display <NUM> are located on a same side of the middle plate <NUM> is used. An example of the assembly process of the electronic device <NUM> provided in this embodiment is as follows:
As shown in <FIG>, first, the locking bracket <NUM> is connected to the middle frame <NUM>, and then the first display <NUM> is moved to a side of the middle frame <NUM>, so that the first display <NUM> is opposite to the middle plate <NUM>, and one end that is of the connection segment <NUM> and that is away from the bent segment <NUM> is attached to the locking bracket <NUM>; and the mainboard <NUM> is moved to a side that is of the first display <NUM> and that faces the middle frame <NUM>, so that a preset included angle θ exists between the first surface <NUM> of the mainboard <NUM> and a surface that is of the middle plate <NUM> and that is away from the first display <NUM>; and then, as shown in <FIG> and <FIG>, the mainboard <NUM> is rotated until the mainboard <NUM> is in contact with the middle plate <NUM>. In this case, a part that is of the mainboard <NUM> and that corresponds to the first display <NUM> is aligned with the opening <NUM>, and the female socket <NUM> on the mainboard <NUM> is buckled with the male socket <NUM> on the connection segment <NUM>, so that the mainboard <NUM> is connected to the first display <NUM>. Herein, a preset angle may be greater than or equal to <NUM> degrees and less than or equal to <NUM> degrees. When the preset angle is <NUM> degrees, the mainboard <NUM> is first erected vertically during mounting.

As shown in <FIG>, the functional component <NUM> is mounted in the first recess <NUM>, and the battery <NUM> is mounted in the second recess <NUM>; and then the second display <NUM> is moved to the other side of the middle frame <NUM>, so that the mounting segment <NUM> of the second flexible printed circuit board <NUM> is connected to the second surface <NUM> of the mainboard <NUM>. Because the second flexible printed circuit board <NUM> also has a redundant part, the second flexible printed circuit board <NUM> can extend to enable the second display <NUM> to be inclined to the middle plate <NUM>, and a space can be provided between the second display <NUM> and the middle plate <NUM>, so that another part can perform a mounting operation in the space.

As shown in <FIG>, the cover plate <NUM> is mounted on a side that is of the mainboard <NUM> and that is away from the first display <NUM>, so that the cover plate <NUM> covers on the mainboard <NUM>; then the second display <NUM> is moved to make the second display <NUM> face the middle plate <NUM>; and then the second display <NUM> is connected to the middle plate <NUM>, to complete mounting of the electronic device <NUM>.

In the descriptions of embodiments of this application, it should be noted that unless otherwise specified and defined explicitly, the terms "mount", "connected to" and "connect" should be understood in a broad sense, and for example, may be a fixed connection or an indirect connection by using an intermediate medium, or may be internal communication between two elements or an interaction relationship between two elements. A person of ordinary skill in the art can understand specific meanings of the foregoing terms in embodiments of this application based on a specific situation.

The device or element referred to in or implied in embodiments of this specification needs to have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on embodiments of this specification. In the descriptions of embodiments of this application, "a plurality of" means two or more, unless otherwise specifically defined.

In the specification of embodiments, claims, and accompanying drawings of this application, the terms "first", "second", "third", "fourth", and the like (if existent) are intended to distinguish between similar objects but do not necessarily indicate a specific order or sequence. It should be understood that the data termed in such a way is interchangeable in proper circumstances, so that embodiments described herein can be implemented in orders except the order illustrated or described herein. In addition, the terms "include" and "have", and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, a method, a system, a product, or a device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or are inherent to the process, method, product, or device.

The term "a plurality of" in this specification refers to two or more. The term "and/or" in this specification describes only an association relationship for describing associated objects and represents that three relationships can exist. For example, "A and/or B" can represent the following three cases: Only A exists, both A and B exist, and only B exists. In addition, the character "/" in this specification usually indicates an "or" relationship between the associated objects. In a formula, the character "/" indicates that the associated objects are in a "division" relationship.

Claim 1:
An electronic device (<NUM>), comprising:
a middle frame (<NUM>), comprising a middle plate (<NUM>) and a frame (<NUM>) connected to a circumferential edge of the middle plate (<NUM>), wherein an opening (<NUM>) is disposed on the middle plate (<NUM>);
a first display (<NUM>) and a second display (<NUM>), respectively disposed on two sides of the middle plate (<NUM>);
a mainboard (<NUM>), mounted on the middle plate (<NUM>) and facing the opening (<NUM>);
a first flexible printed circuit board (<NUM>), wherein one end of the first flexible printed circuit board (<NUM>) is connected to a surface that is of the first display (<NUM>) and that faces the middle plate (<NUM>), and the other end of the first flexible printed circuit board (<NUM>) extends between the first display (<NUM>) and the mainboard (<NUM>) and is electrically connected to a surface that is of the mainboard (<NUM>) and that faces the first display (<NUM>); and
a second flexible printed circuit board (<NUM>), wherein one end of the second flexible printed circuit board (<NUM>) is connected to a surface that is of the second display (<NUM>) and that faces the middle plate (<NUM>), and the other end of the second flexible printed circuit board (<NUM>) extends between the second display (<NUM>) and the mainboard (<NUM>) and is electrically connected to a surface that is of the mainboard (<NUM>) and that faces the second display (<NUM>).