A magnetic phone back holder with display screen

By integrating magnetic fixation and an electronic display screen into the phone holder, and combining NFC, Bluetooth, and WIFI technologies, the problem of the traditional phone holder's single function is solved. It achieves stable fixation of the display screen and diversified content updates, as well as flexible rotation and convenient adjustment of the holder, thus improving the user experience.

CN224289862UActive Publication Date: 2026-05-26SHENZHEN SHUANGCHENG BAIFENG TECHNOLOGY CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
SHENZHEN SHUANGCHENG BAIFENG TECHNOLOGY CO LTD
Filing Date
2025-07-24
Publication Date
2026-05-26

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Abstract

This utility model relates to the field of mobile phone back clip holder technology, and discloses a magnetic mobile phone back clip holder with a display screen, comprising a mobile phone back shell, a magnetic ring holder, and a holder rotating component. The back of the mobile phone back shell is magnetically engaged with the magnetic component. The inner side of the fixed magnetic ring has a centrally located magnetic ring, and a positioning block is provided on the outer side of the back. The magnetic ring engages with the back of the mobile phone back shell through magnetic engagement. The back of the magnetic ring holder has a positioning groove, and the fixed magnetic ring is located on its back. The back of the magnetic ring is inside the back of the magnetic ring holder. The positioning groove and the positioning block engage to achieve a stable connection. The magnetic ring holder has an internal electronic display screen. The positioning post on the back of the fixed ring is inserted into the positioning hole, so that the front end of the electronic display screen is tightly attached to the back of the fixed ring. The fixed ring and the magnetic ring holder can be used to replace the electronic display screen. The inner wall of the holder rotating component has an annular rotating protrusion. The holder rotating component is sleeved with the magnetic ring holder. The friction groove engages with the friction block, allowing it to stay stably at any angle. The holder ring can be stored in it or rotated out to serve as a holder.
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Description

Technical Field

[0001] This utility model relates to the field of mobile phone back clip holder technology, specifically a magnetic mobile phone back clip holder with a display screen. Background Technology

[0002] A phone back cover holder is an accessory that is installed on the back of a phone to support it and also serves as a decoration. An electronic swivel display is a replaceable decorative component with integrated display functionality, allowing users to personalize their phones by displaying different content. In daily use, users need a phone back cover holder to provide stable support for watching videos and other operations, while also wanting to decorate their phones and express their individuality with the diverse display content of an electronic swivel display. Therefore, combining an electronic swivel display with a phone back cover holder satisfies users' dual needs for functionality and decoration, making it of significant practical value.

[0003] Traditional phone holder technology, whether magnetic or other types, primarily focuses on supporting and securing the phone, resulting in limited functionality and a lack of innovation. Currently, there is no precedent for incorporating electronic display screens—which offer multiple transmission technologies and flexible content updates—into phone holders. This technological gap prevents traditional phone holders from meeting users' personalized needs. Users wishing to display personalized content must rely on the phone's own screen or static stickers; the former occupies phone screen space, while the latter cannot be dynamically updated. Furthermore, simple data interaction between the holder and the phone is impossible, significantly limiting the phone holder's functional expansion. Therefore, we propose a magnetic phone back sticker holder with an integrated display screen. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a magnetic mobile phone back sticker holder with a display screen, which solves the aforementioned problems.

[0005] To achieve the above-mentioned objectives, this utility model provides the following technical solution: a magnetic mobile phone back sticker holder with a display screen, comprising:

[0006] The mobile phone back cover, magnetic ring bracket, electronic swivel display screen body and bracket rotating part are provided. The magnetic ring bracket has a fixed ring inside. The electronic swivel display screen body is provided between the magnetic ring bracket and the fixed ring. The bracket rotating part is sleeved on the magnetic ring bracket. The front end of the bracket rotating part is hinged with a bracket ring.

[0007] A magnetic suction assembly is provided on the back of the magnetic ring bracket. The magnetic suction assembly includes a fixed magnetic ring and a magnetic suction ring. The magnetic suction ring is located on the back of the fixed magnetic ring. The back of the mobile phone back cover is magnetically engaged with the magnetic suction assembly.

[0008] Preferably, the display screen used in the electronic barbell display body includes, but is not limited to, e-ink screen, TFT LCD screen and OLED display screen.

[0009] Preferably, the fixed magnetic ring has a magnetic suction ring inside, which is located at the center of the fixed magnetic ring. The back of the fixed magnetic ring has multiple positioning blocks that are symmetrical about the central axis and are T-shaped. The positioning blocks are located on the outside of the fixed magnetic ring. The fixed magnetic ring is magnetically engaged with the magnetic suction ring and is located on the back of the mobile phone back cover.

[0010] Preferably, the back of the magnetic ring bracket is provided with multiple T-shaped positioning grooves that are symmetrical about the central axis. The fixing magnetic ring is disposed on the back of the magnetic ring bracket, and the back of the magnetic suction ring is disposed inside the back of the magnetic ring bracket. The positioning grooves are engaged with the positioning blocks.

[0011] Preferably, the front end of the magnetic ring bracket has an annular mounting groove, and the outer side of the mounting groove has multiple annular positioning holes. The mounting groove contains an electronic vibrator display screen. The back of the fixing ring has multiple annularly distributed positioning posts, which are inserted into the positioning holes. The front end of the electronic vibrator display screen is in close contact with the back of the fixing ring.

[0012] Preferably, the inner side of the outer cylindrical surface of the magnetic ring bracket is provided with a plurality of semi-circular friction blocks, and the inner cylindrical surface of the bracket rotating part is provided with a circular rotating protrusion, and the inner wall of the rotating protrusion is provided with a plurality of semi-circular friction grooves.

[0013] Preferably, the bracket rotating component is sleeved on the magnetic ring bracket and rotates in cooperation, and the rotating convex ring is disposed on the inner side of the outer cylindrical surface of the magnetic ring bracket, and the friction groove is in frictional cooperation with the friction block.

[0014] Preferably, the front end of the bracket rotating component has an annular bracket storage groove, one side of the front end of the bracket rotating component has a double hinge lug, and one side of the bracket ring has a single hinge lug, wherein the single hinge lug and the double hinge lug are hinged together by a rotating shaft, and the bracket ring is located inside the bracket storage groove.

[0015] Compared with the prior art, this utility model provides a magnetic mobile phone back sticker holder with a display screen, which has the following advantages:

[0016] This magnetic phone back mount holder with a display screen offers dual protection for stability through the cooperation of the magnetic components and the phone back cover. The magnetic ring on the mounting magnetic ring magnetically attracts the phone back cover, while multiple T-shaped positioning blocks mechanically limit the movement of the magnetic ring against the corresponding structure of the phone back cover, providing a solid foundation for the entire holder system. The magnetic ring holder engages with the positioning blocks of the magnetic ring through the positioning groove on the back, further enhanced by the magnetic ring's auxiliary fixation, strengthening the connection between the magnetic ring holder and the magnetic ring. This effectively prevents relative displacement during use and improves the overall structural reliability. For electronic display screens, its installation and use advantages are significant. The mounting groove of the magnetic ring holder provides precise placement space for the display screen, and the positioning pins of the fixing ring, once inserted into the positioning holes, firmly secure the electronic display screen. The design ensures stability during use, preventing shaking from affecting the display effect. The electronic stick display supports various screen types, including e-ink, TFT LCD, and OLED displays. Combined with NFC, Bluetooth, and Wi-Fi transmission technologies, it facilitates content updates and interactive control, greatly enriching the display's functionality and usage scenarios. Regarding stand adjustment and ease of use, the rotating part and magnetic ring stand work together through friction blocks and grooves, allowing the rotating part to rotate flexibly and stay stably at any angle. This allows users to adjust the phone's orientation according to their needs, finding a comfortable angle for watching videos or making video calls. The hinged design of the stand ring and rotating part, combined with the stand storage slot, allows the ring to be stored away when not in use, saving space and avoiding taking up extra room. When in use, it unfolds to stably support the phone. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model;

[0018] Figure 2 This is a schematic diagram showing the structural breakdown of this utility model;

[0019] Figure 3 This is a schematic diagram of the connection structure between the bracket rotating component and the bracket ring of this utility model;

[0020] Figure 4 This is a schematic diagram of the magnetic ring support structure of this utility model;

[0021] Figure 5 This is a schematic diagram of the magnetic ring support structure of this utility model;

[0022] Figure 6 This is a schematic diagram of the fixed magnetic ring structure of this utility model.

[0023] In the diagram: 1. Phone back cover; 2. Fixing magnetic ring; 3. Magnetic ring bracket; 4. Electronic bar display screen; 5. Fixing ring; 6. Bracket rotating part; 7. Bracket ring; 8. Bracket storage slot; 9. Rotating convex ring; 10. Friction groove; 11. Friction block; 12. Positioning hole; 13. Mounting groove; 14. Positioning groove; 15. Positioning block; 16. Magnetic ring. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Please see Figure 1-6 A magnetic phone back holder with a display screen, comprising:

[0026] The mobile phone back cover 1, magnetic ring bracket 3, electronic bar display screen body 4 and bracket rotating part 6 are provided. A fixing ring 5 is provided inside the magnetic ring bracket 3. The electronic bar display screen body 4 is provided between the magnetic ring bracket 3 and the fixing ring 5. The bracket rotating part 6 is sleeved on the magnetic ring bracket 3. A bracket ring 7 is hinged to one side of the front end of the bracket rotating part 6.

[0027] A magnetic suction assembly is provided on the back of the magnetic ring bracket 3. The magnetic suction assembly includes a fixed magnetic ring 2 and a magnetic ring 16. The magnetic ring 16 is provided on the back of the fixed magnetic ring 2. The back of the mobile phone back cover 1 is magnetically engaged with the magnetic suction assembly.

[0028] Furthermore, the electronic barbell display body 4 uses displays including but not limited to e-ink screens, TFT LCD screens, and OLED screens. The transmission method of the electronic barbell display body 4 is more convenient, integrating NFC, Bluetooth, and WIFI technologies. When using NFC technology, the electronic barbell display body with a built-in NFC chip can establish a communication link within a short distance by bringing it close to devices such as mobile phones and using NFC magnetic field induction. This allows for the rapid transmission of personalized patterns, simple interactive commands, and other data, enabling the updating of decorative content or triggering specific interactions, such as transmitting custom DIY pattern data to the display screen.

[0029] Using Bluetooth technology, the electronic bar display can be paired and connected with terminals such as mobile phones, enabling more flexible and long-distance data transmission than NFC. In addition to transmitting decorative content, it can also transmit control commands, such as sending commands from a mobile APP to make the display switch themes and adjust brightness.

[0030] When the electronic bar display is connected to a Wi-Fi network, it has the ability to interact with external network data. Users can control and transfer data through a dedicated application on their mobile devices, making it more convenient and diverse to update the decorative content and control the functions of the electronic bar display.

[0031] Furthermore, a magnetic ring 16 is provided inside the fixed magnetic ring 2. The magnetic ring 16 is located at the center of the fixed magnetic ring 2. Multiple T-shaped positioning blocks 15 with central axis symmetry are provided on the back of the fixed magnetic ring 2. The positioning blocks 15 are located on the outside of the fixed magnetic ring 2. The fixed magnetic ring 2 is magnetically engaged with the magnetic ring 16 and is set on the back of the mobile phone back cover 1. Through the magnetic engagement of the magnetic ring 16 and the setting of the positioning blocks 15, the fixed magnetic ring 2 can be stably installed on the back of the mobile phone back cover 1, providing a basic fixation for the connection of other components.

[0032] Furthermore, the back of the magnetic ring bracket 3 is provided with multiple T-shaped positioning grooves 14 that are symmetrical about the central axis. The fixed magnetic ring 2 is set on the back of the magnetic ring bracket 3, and the back of the magnetic suction ring 16 is set inside the back of the magnetic ring bracket 3. The positioning grooves 14 and the positioning blocks 15 are engaged to achieve a stable connection between the magnetic ring bracket 3 and the fixed magnetic ring 2, prevent relative displacement between the two, and enhance the overall structural stability.

[0033] Furthermore, the front end of the magnetic ring bracket 3 has an annular mounting groove 13, and the outer side of the mounting groove 13 has multiple annular positioning holes 12. The electronic swivel display screen body 4 is installed inside the mounting groove 13. The back of the fixing ring 5 has multiple annularly distributed positioning posts, which are inserted into the positioning holes 12. The front end of the electronic swivel display screen body 4 is close to the back of the fixing ring 5, which stably fixes the electronic swivel display screen body 4 in the magnetic ring bracket 3, ensuring the stability of the electronic swivel display screen body 4 and facilitating its replacement.

[0034] Furthermore, the inner side of the outer cylindrical surface of the magnetic ring bracket 3 is provided with multiple semi-circular friction blocks 11, and the inner cylindrical surface of the bracket rotating part 6 is provided with a circular rotating protrusion 9. The inner wall of the rotating protrusion 9 is provided with multiple semi-circular friction grooves 10, which provide a structural basis for the rotational cooperation of the two and ensure the stability of the rotation process.

[0035] Furthermore, the bracket rotating part 6 is sleeved on the magnetic ring bracket 3 and rotates in cooperation, and the rotating convex ring 9 is set on the inner side of the outer cylindrical surface of the magnetic ring bracket 3. The friction groove 10 and the friction block 11 are in frictional cooperation, so as to realize the flexible rotation of the bracket rotating part 6, so that it can stay stably at any angle and facilitate the adjustment of direction.

[0036] Furthermore, the front end of the bracket rotating part 6 is provided with a ring-shaped bracket storage groove 8. One side of the front end of the bracket rotating part 6 is provided with a double hinge ear, and one side of the bracket ring 7 is provided with a single hinge ear. The single hinge ear and the double hinge ear are hinged together by a rotating shaft. The bracket ring 7 is set inside the bracket storage groove 8, so as to realize the storage and unfolding of the bracket ring 7. It saves space when not in use and can be used as a stand to stably support the mobile phone when in use.

[0037] Structural Description:

[0038] Phone back cover 1: It is the basic protective component of the phone. The back of the phone magnetically engages with the magnetic component, providing the mounting base for the entire stand system and serving as the carrier for connecting the stand and the phone.

[0039] Fixed magnetic ring 2: There is a T-shaped positioning block 15 on the back, and a magnetic ring 16 is provided inside. It cooperates with the back cover of the mobile phone 1 through magnetic attraction and positioning block to provide stable support for other components.

[0040] Magnetic ring bracket 3: The back has a positioning groove 14 that engages with the positioning block 15 that fixes the magnetic ring 2, and the front has an installation groove 13 for mounting the electronic bar display screen body 4. It is the core of the connection between various components.

[0041] Electronic barbell display screen 4: placed in the mounting slot 13, supports multiple display screen types, integrates NFC and other transmission technologies, can display personalized content and interact with devices;

[0042] Fixing ring 5: The back has a positioning post that inserts into the positioning hole 12, and the front end is close to the electronic bar display screen body 4, which is stably fixed in the magnetic ring bracket 3 for easy replacement;

[0043] Rotating component 6: It is sleeved on the magnetic ring bracket 3 and has a rotating protrusion 9 on its inner wall. It cooperates with the friction block 11 to achieve flexible rotation and can stay at any angle.

[0044] Stand ring 7: One side single hinge ear is hinged to the double hinge ear of the stand rotating part 6, which can be stored in the stand storage slot 8 and can stably support the mobile phone when unfolded;

[0045] Support storage slot 8: Located inside the front end of the support rotating part 6, it is ring-shaped and used to store the support ring 7, saving space when not in use;

[0046] Rotating convex ring 9: It is circular in shape on the inner cylindrical surface of the bracket rotating part 6, and has a friction groove 10 on the inner wall, which provides a structural basis for rotating cooperation with the magnetic ring bracket 3.

[0047] Friction groove 10: It is formed on the inner wall of the rotating convex ring 9 and is semi-circular in shape. It is in frictional engagement with the friction block 11 to ensure the stable rotation of the bracket rotating part 6.

[0048] Friction block 11: It is located on the inner side of the outer cylindrical surface of the magnetic ring bracket 3, and is semi-circular in shape. It cooperates with the friction groove 10 so that the bracket rotating part 6 can be stably stopped at any angle.

[0049] Positioning holes 12: are arranged in a ring on the outside of the mounting groove 13, for the positioning pins of the fixing ring 5 to be inserted, so as to realize the connection between the fixing ring 5 and the magnetic ring bracket 3;

[0050] Mounting slot 13: Inside the front end of the magnetic ring bracket 3, it is ring-shaped and used to place the electronic bar display screen body 4, providing it with installation space;

[0051] Positioning groove 14: Located on the back of the magnetic ring bracket 3, it is T-shaped and symmetrical about the central axis, and engages with the positioning block 15 to achieve a stable connection between the magnetic ring bracket 3 and the fixed magnetic ring 2.

[0052] Positioning block 15: Located on the outer side of the back of the fixed magnetic ring 2, it is T-shaped and symmetrical about the central axis, and engages with the positioning groove 14 to prevent the fixed magnetic ring 2 from shifting from the magnetic ring bracket 3;

[0053] Magnetic ring 16: Located at the center of the fixed magnetic ring 2, its back is magnetically engaged with the back cover of the mobile phone, enhancing the connection stability between the fixed magnetic ring 2 and the back cover of the mobile phone.

[0054] Working principle: First, the overall magnetic fixing structure works in synergy. The phone back cover 1 serves as the basic supporting component, and its back surface magnetically engages with the magnetic assembly. The magnetic assembly includes a fixing magnetic ring 2 and a magnetic ring 16. The magnetic ring 16 is located at the center of the fixing magnetic ring 2. The back surface of the fixing magnetic ring 2 has multiple T-shaped positioning blocks 15 symmetrical about the central axis, distributed on the outer side. When the fixing magnetic ring 2 is installed on the back of the phone back cover 1, the magnetic attraction force of the magnetic ring 16 and the mechanical limiting force of the positioning blocks 15 work together to stably attach the fixing magnetic ring 2 to the phone back cover 1, providing a stable foundation. The connection between the magnetic ring bracket 3 and the fixing magnetic ring 2 relies on the snap-fit ​​connection between the positioning groove 14 and the positioning block 15. The magnetic ring bracket 3 has multiple T-shaped positioning grooves 14 symmetrical about its central axis on its back. When the magnetic ring 2 is installed on the back of the magnetic ring bracket 3, the positioning block 15 is precisely engaged with the positioning groove 14. At the same time, the magnetic ring 16 is embedded inside the back of the magnetic ring bracket 3. This double fixing method prevents relative displacement between the two and enhances the overall structural stability. The installation and fixing of the electronic swivel display screen 4 relies on the cooperation of the mounting groove 13 and the fixing ring 5. The front end of the magnetic ring bracket 3 has an annular mounting groove 13 inside and multiple annular positioning holes 12 on the outside. The electronic swivel display screen 4 is placed in the mounting groove 13, and the multiple positioning posts on the back of the fixing ring 5 are inserted into the positioning holes 12, with its back tightly against the electronic swivel. The front end of the display body 4 is firmly fixed inside the magnetic ring bracket 3, ensuring both stability and ease of replacement. The electronic barbell display body 4 can use an e-ink screen, TFT LCD screen, or OLED screen, and data transmission is achieved through NFC, Bluetooth, and WIFI technologies. NFC technology supports fast short-range transmission of personalized patterns and simple commands; Bluetooth technology enables flexible connections over longer distances, allowing the transmission of decorative content and control commands; WIFI connectivity provides network interaction capabilities, allowing users to remotely update content and control functions via a mobile app. The bracket rotation adjustment function is achieved through a friction structure, and the inner side of the outer cylindrical surface of the magnetic ring bracket 3 has multiple semi-circular arcs. The rotating ring 9 on the inner wall of the bracket rotating component 6 has a corresponding semi-circular friction groove 10. When the bracket rotating component 6 is sleeved on the magnetic ring bracket 3, the friction groove 10 and the friction block 11 fit tightly together, forming stable friction damping, so that the bracket rotating component 6 can rotate flexibly and stay at any angle. The storage and support functions of the bracket ring 7 are accomplished by a hinge structure. The front end of the bracket rotating component 6 is provided with a circular bracket storage groove 8. The double hinge ear on one side of its front end is hinged to the single hinge ear of the bracket ring 7 through a rotating shaft. When not in use, the bracket ring 7 can be stored in the bracket storage groove 8 to save space; when in use, the bracket ring 7 can be unfolded to serve as a support structure to stably place the mobile phone.

[0055] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A magnetic mobile phone back holder with a display screen, characterized in that, include: The mobile phone back cover (1), magnetic ring bracket (3), electronic bar display screen body (4) and bracket rotating part (6) are provided. The magnetic ring bracket (3) has a fixed ring (5) inside. The electronic bar display screen body (4) is provided between the magnetic ring bracket (3) and the fixed ring (5). The bracket rotating part (6) is sleeved on the magnetic ring bracket (3). The bracket ring (7) is hinged to one side of the front end of the bracket rotating part (6). A magnetic suction assembly is provided on the back of the magnetic ring bracket (3). The magnetic suction assembly includes a fixed magnetic ring (2) and a magnetic suction ring (16). The magnetic suction ring (16) is provided on the back of the fixed magnetic ring (2). The back of the mobile phone back cover (1) is magnetically engaged with the magnetic suction assembly.

2. A magnetic mobile phone back holder with a display screen according to claim 1, characterized in that, The display screen used in the electronic barbell display body (4) includes, but is not limited to, e-ink screen, TFT LCD screen and OLED display screen.

3. A magnetic mobile phone back sticker holder with a display screen according to claim 1, characterized in that, The fixed magnetic ring (2) is provided with a magnetic suction ring (16) inside. The magnetic suction ring (16) is located at the center of the fixed magnetic ring (2). The back of the fixed magnetic ring (2) is provided with a plurality of positioning blocks (15) that are symmetrical about the central axis and are T-shaped. The positioning blocks (15) are located on the outside of the fixed magnetic ring (2). The fixed magnetic ring (2) is magnetically engaged with the magnetic suction ring (16) and is located on the back of the mobile phone back cover (1).

4. A magnetic mobile phone back bracket with a display screen according to claim 1, characterized in that, The magnetic ring bracket (3) has multiple T-shaped positioning grooves (14) that are symmetrical about the central axis on the back. The fixed magnetic ring (2) is set on the back of the magnetic ring bracket (3). The back of the magnetic suction ring (16) is set inside the back of the magnetic ring bracket (3). The positioning grooves (14) are engaged with the positioning block (15).

5. A magnetic mobile phone back bracket with a display screen according to claim 4, characterized in that, The front end of the magnetic ring bracket (3) is provided with a ring-shaped mounting groove (13), and a plurality of annular positioning holes (12) are provided on the outside of the mounting groove (13). An electronic swivel display screen body (4) is provided inside the mounting groove (13). A plurality of annularly distributed positioning posts are provided on the back of the fixing ring (5). The positioning posts are inserted into the positioning holes (12). The front end of the electronic swivel display screen body (4) is close to the back of the fixing ring (5).

6. A magnetic mobile phone back bracket with a display screen according to claim 1, characterized in that, The magnetic ring bracket (3) has multiple semi-circular friction blocks (11) on the inner side of its outer cylindrical surface. The inner cylindrical surface of the bracket rotating part (6) has a circular rotating convex ring (9). The inner wall of the rotating convex ring (9) has multiple semi-circular friction grooves (10).

7. A magnetic mobile phone back bracket with a display screen according to claim 6, characterized in that, The bracket rotating part (6) is sleeved on the magnetic ring bracket (3) and rotates in cooperation, and the rotating convex ring (9) is set on the inner side of the outer cylindrical surface of the magnetic ring bracket (3), and the friction groove (10) is in frictional cooperation with the friction block (11).

8. A magnetic mobile phone back bracket with a display screen according to claim 7, characterized in that, The front end of the bracket rotating part (6) is provided with a ring-shaped bracket storage groove (8). The front end of the bracket rotating part (6) is provided with a double hinge ear on one side, and the bracket ring (7) is provided with a single hinge ear on one side. The single hinge ear and the double hinge ear are hinged together by a rotating shaft, and the bracket ring (7) is located inside the bracket storage groove (8).