Patent Publication Number: US-2023164935-A1

Title: LED Display Device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority to Chinese patent application No. 202111400095.2, filed to the China National Intellectual Property Administration on Nov. 19, 2021, the disclosure of which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The disclosure relates to a technical field of light-emitting diode (LED) display, in particular to an LED display device. 
     BACKGROUND 
     Light-emitting diode (LED) display devices are electronic display screens composed of LED dot matrices. The forms of display contents on the screen, for example, texts, animations, pictures and videos are timely switched by turning on and off red and green lamp beads, and the display control of assemblies is implemented by means of modular structures. The LED display device includes an LED display screen, a control system and a power source system. The LED display screens are composed of LED dot matrices to emit light. The control system switches the display contents on the screens by adjusting and controlling the on/off state of areas. The power source system is used to convert input voltages and currents to satisfy the requirements of the display screen. The LED display screen can switch different forms of various information presentation modes, and can be used indoors and outdoors, with incomparable advantages over other display screens. Featuring high brightness intensity, low power consumption, low voltage requirement, small size, convenient use, long service life, stable impact resistance, and strong resistance to external interference, the LED display screen develops rapidly and has been widely applied in various fields. 
     The LED display devices in the related art are all formed by splicing LED display screens. Since stress deformation will be resulted from the gravity and long-term use, the gravity of the upper-layer LED display screens acts on the lower-layer LED display screens to press the lower-layer LED display screens. In this case, when the lower-layer LED display screens are required to be repaired and replaced, it will be difficult to take out the lower-layer LED display screens under pressure from the gravity. 
     In the prior art, when the LED display screens are in the front-maintained mode, if a certain lower-layer LED display screen is required to be repaired and replaced, all the upper-layer LED display screens above the LED display screen are required to be detached, resulting in difficult repair. 
     SUMMARY 
     The main objective of the disclosure is to provide a light-emitting diode (LED) display device, so as to solve the problem that in the prior art, when a certain LED display screen at a lower layer is required to be repaired and replaced, all upper-layer LED display screens above the LED display screen are required to be detached, resulting in difficult repair. 
     In order to realize the above objective, the disclosure provides an LED display device. The LED display device includes: a support; a plurality of display assemblies mounted on a front side of the support, wherein the plurality of display assemblies are arranged in an array on the support, each display assembly is slidably arranged in an upper-lower direction, and each display assembly includes a frame and an LED display screen detachably arranged on a front side of the frame; and a plurality of gas bags, wherein each gas bag is arranged between the frames of two display assemblies adjacent to each other in the upper-lower direction, each gas bag has an expanded state and a flat state, when the gas bag is in the flat state, two adjacent display assemblies located above and below the gas bag cooperate with each other in a contact manner, and when the gas bag is switched from the flat state to the expanded state, the frame above the gas bag may be driven to slide upwards, such that a detachment gap is formed between the two adjacent display assemblies located above and below the gas bag. 
     In some embodiments, each gas bag includes a flat gas bag body and a gas nozzle arranged on the gas bag body, first accommodation recesses for accommodating the gas bag body are provided on the frames of the two adjacent display assemblies located above and below, and the gas nozzle passes through the frames. 
     In some embodiments, the LED display device further includes a gas source device for supplying gas to the plurality of gas bags, the gas source device includes a gas pump and/or an inflator, the gas source device further includes a plurality of first gas channels in communication with the gas pump and/or the inflator, the plurality of first gas channels are connected in parallel, the plurality of first gas channels are in communication with the plurality of gas bags in a one-to-one correspondence manner, and a first gate valve is arranged on each of the first gas channels. 
     In some embodiments, the gas source device further includes an overflow gas channel in communication with any one of the first gas channels, and an overflow valve is arranged on the overflow gas channel. 
     In some embodiments, the gas source device includes the gas pump and the inflator, the gas pump and the inflator are connected in parallel, the plurality of first gas channels converge at a junction, the junction is in communication with the gas pump by a second gas channel, a first one-way valve is arranged on the second gas channel, a third gas channel is arranged between an inlet of the first one-way valve and the inflator, a second one-way valve is arranged on the third gas channel, a fourth gas channel is arranged between the junction and an outlet of the first one-way valve, and a second gate valve is arranged on the fourth gas channel. 
     In some embodiments, the LED display device further includes a plurality of longitudinal rods arranged at intervals and a plurality of horizontal rods arranged at intervals, the longitudinal rods and the horizontal rods are arranged in a staggered manner, every two adjacent longitudinal rods pass through one frame, every two adjacent horizontal rods pass through one frame, and a movement gap in the upper-lower direction is formed between a through hole of each frame allowing the horizontal rods to pass through and a corresponding horizontal rods. 
     In some embodiments, a chute is provided on one frame of two adjacent frames located left and right, and a slide block matching the chute in an inserted manner is arranged on the other frame. 
     In some embodiments, a second accommodation recess for accommodating a ball is provided on a back side of each frame, and a portion of the ball protruding out of an opening of the second accommodation recess cooperates with a surface of the support in a contact manner. 
     In some embodiments, a pair of limiting members located on an upper side and a lower side of the ball is arranged on the frame, and the limiting members are detachably located in the second accommodation recess. 
     In some embodiments, the LED display device further includes a plurality of fasteners penetrating through the support, one corresponding frame is adjustably mounted on the support by each fastener, an avoiding hole allowing the fasteners to pass through are provided on the support, an aperture of the avoiding hole is greater than an outer diameter of each fastener, connecting holes tightly connected to the fasteners are provided on the frames, the LED display device further includes a plurality of damping members, the plurality of damping members and the plurality of fasteners are arranged in a one-to-one correspondence manner, and the damping members are located between the avoiding holes and heads of the fasteners, such that the fasteners may swing up and down in the avoiding holes when the frames slide up and down. 
     In some embodiments, the fasteners include screw heads and screw rods connected with the screw heads, the connecting holes are screw holes connected with the screw rods, the avoiding holes include elongated hole sections for avoiding the screw rods, and reamed hole sections for accommodating the screw heads, each reamed hole section has an aperture greater than a maximum value of apertures of the elongated hole sections, step surfaces are formed between the reamed hole sections and the elongated hole sections, the damping members include springs sleeving the screw rods, and the springs are located between the screw heads and the step surfaces. 
     By employing the technical solution of the disclosure, the LED display device includes: a support, a plurality of display assemblies and a plurality of gas bags. The plurality of display assemblies are mounted on a front side of the support. The plurality of display assemblies are arranged in an array on the support. Each display assembly is slidably arranged in an upper-lower direction. Each display assembly includes a frame and an LED display screen detachably arranged on a front side of the frame. Each gas bag is arranged between the frames of two display assemblies adjacent to each other in the upper-lower direction, and each gas bag has an expanded state and a flat state. In the disclosure, when the gas bag is in the flat state, two adjacent display assemblies located above and below the gas bag cooperate with each other in a contact manner. When a lower LED display screen is required to be replaced, the gas bag above the LED display screen required to be repaired is switched from the flat state to the expanded state, and the frame above the gas bag may be driven to slide upwards, such that a detachment gap is formed between the two adjacent display assemblies located above and below the gas bag. In this way, the LED display screen above the lower LED display screen required to be repaired is slightly lifted, such that the LED display screen required to be maintained is not pressed by the upper LED display screen, the lower LED display screen required to be maintained may be easily taken down from the corresponding frame and taken out from the plurality of display assemblies. Therefore, the LED display screen required to be maintained is easy to repair. Furthermore, in the situation that a plurality of LED display screens are arranged above an LED display screen required to be maintained, the lower LED display screen to be maintained may be easily replaced and repaired, and front maintenance is convenient. Therefore, the technical solution of the disclosure may solve the problem that in the prior art, when a certain LED display screen at a lower layer is required to be repaired and replaced, all upper-layer LED display screens above the LED display screen are required to be detached, resulting in difficult repair. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings of the description, which constitutes a part of the disclosure, are used to provide further understanding of the disclosure, and illustrative embodiments of the disclosure and the description thereof are used to explain the disclosure, which are not intended to unduly limit the disclosure. In the accompanying drawings: 
         FIG.  1    shows a solid schematic structural diagram of an embodiment of a light-emitting diode (LED) display device according to the disclosure; 
         FIG.  2    shows a solid schematic structural diagram in the situation that an upper LED display assembly of the LED display device in  FIG.  1    is lifted by a gas bag; 
         FIG.  3    shows a solid schematic structural diagram in the situation that a lower LED display screen of the LED display device in  FIG.  1    is taken out; 
         FIG.  4    shows a solid schematic structural diagram from another angle of the LED display device in  FIG.  1   ; 
         FIG.  5    shows a schematic diagram of a gas source device of the LED display device in  FIG.  1   ; 
         FIG.  6    shows a solid schematic structural diagram of a front side of a mounting box of the LED display device in  FIG.  1   ; 
         FIG.  7    shows a solid schematic structural diagram of a back side of a mounting box of the LED display device in  FIG.  1   ; 
         FIG.  8    shows an exploded schematic structural diagram of the LED display device in  FIG.  1   ; 
         FIG.  9    shows an enlarged schematic diagram of a position A of the LED display device in  FIG.  8   ; 
         FIG.  10    shows a solid schematic structural diagram in the situation that the LED display device in  FIG.  4    is partially cut; 
         FIG.  11    shows an enlarged schematic diagram of a position B of the LED display device in  FIG.  10   ; 
         FIG.  12    shows an enlarged schematic diagram of a position C of the LED display device in  FIG.  10   ; 
         FIG.  13    shows an enlarged schematic diagram of a position D of the LED display device in  FIG.  11   ; 
         FIG.  14    shows a solid schematic structural diagram of fasteners and damping members of the LED display device in  FIG.  1   ; 
         FIG.  15    shows a solid schematic structural diagram of a gas bag of the LED display device in  FIG.  1   ; 
         FIG.  16    shows a schematic front view of the LED display device in  FIG.  1    with a plurality of LED display screens detached; and 
         FIG.  17    shows a solid schematic structural diagram of a frame of the LED display device in  FIG.  1   . 
     
    
    
     The above accompanying drawings include the following reference numerals: 
       10 : support;  11 : avoiding hole;  111 : elongated hole section;  112 : reamed hole section;  20 : display assembly;  21 : frame;  211 : first accommodation recess;  212 : second accommodation recess;  213 : connecting hole;  22 : LED display screen;  30 : gas bag;  31 : gas bag body;  32 : gas nozzle;  40 : gas source device;  41 : gas pump;  42 : inflator;  431 : first gas channel;  432 : second gas channel;  433 : third gas channel;  434 : fourth gas channel;  44 : first gate valve;  45 : overflow valve;  46 : first one-way valve;  47 : second one-way valve;  48 : second gate valve;  51 : longitudinal rod;  52 : horizontal rod;  61 : chute;  62 : slide block;  63 : ball;  64 : limiting member;  71 : fastener;  711 : screw head;  712 : screw rod;  72 : damping member;  73 : washer;  80 : mounting box;  81 : gas inlet;  82 : gas outlet;  83 : inflating port; and  84 : gas pump switch. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The technical solutions of the embodiments of the disclosure will be clearly and completely described below in combination with the accompanying drawings in the embodiments of the disclosure. Apparently, the described embodiments are merely part rather than all of the embodiments of the disclosure. The following description of at least one illustrative embodiment is merely illustrative in nature and in no way serves as any limitation of the disclosure and application or uses thereof. On the basis of the embodiments of the disclosure, all other embodiments obtained by those of ordinary skill in the art without making inventive efforts all fall within the protection scope of the disclosure. 
     It should be noted that the terms used herein are merely for describing the specific implementations and are not intended to limit the illustrative implementations according to the disclosure. As used herein, a singular form is intended to include a plural form as well, unless the context clearly dictates otherwise, and in addition, it should be understood that the terms “contain” and/or “include”, when used in the description, specify the presence of features, steps, operations, devices, assemblies, and/or combinations thereof. 
     Unless specifically stated otherwise, relative arrangements, numerical expressions and values of the assemblies and steps stated in these embodiments do not limit the scope of the disclosure. Moreover, it should be understood that the sizes of the various parts shown in the accompanying drawings are not drawn according to an actual scale for ease of description. Technique, methods and devices known to those of ordinary skill in the related art may not be discussed in detail, but should be considered as a part of the authorized description where appropriate. In all examples shown and discussed herein, any specific value should be interpreted as merely illustrative and not as limiting. Thus, other examples of the illustrative embodiments can have different values. It should be noted that similar numerals and letters denote similar items in the following accompanying drawings, and therefore, once a certain item is defined in one figure, it is not required to be further discussed in the subsequent figures. 
     As shown in  FIGS.  1 - 5   , a light-emitting diode (LED) display device in the embodiment includes: a support  10 , a plurality of display assemblies  20  and a plurality of gas bags  30 . The plurality of display assemblies  20  are mounted on a front side of the support  10 . The plurality of display assemblies  20  are arranged in an array on the support  10 . Each display assembly  20  is slidably arranged in an upper-lower direction. Each display assembly  20  includes a frame  21  and an LED display screen  22  detachably arranged on a front side of the frame  21 . Each gas bag  30  is arranged between the frames  21  of two display assemblies  20  adjacent to each other in the upper-lower direction, and each gas  30  bag has an expanded state and a flat state. In the embodiment, when the gas bag  30  is in the flat state, two adjacent display assemblies  20  located above and below the gas bag  30  cooperate with each other in a contact manner, and when the gas bag  30  is switched from the flat state to the expanded state, the frame  21  above the gas bag  30  may be driven to slide upwards, such that a detachment gap is formed between the two adjacent display assemblies  20  located above and below the gas bag  30 . 
     By applying the technical solution of the embodiment, when the gas bag  30  is in the flat state, the two adjacent display assemblies  20  located above and below the gas bag  30  cooperate with each other in a contact manner. When a lower LED display screen  22  is required to be replaced, the gas bag  30  above the LED display screen  22  required to be repaired is switched from the flat state to the expanded state, and the frame  21  above the gas bag  30  may be driven to slide upwards, such that a detachment gap is formed between the two adjacent display assemblies  20  located above and below the gas bag  30 . In this way, the LED display screen  22  above the lower LED display screen  22  required to be repaired is slightly lifted, such that the LED display screen  22  required to be maintained is not pressed by the upper LED display screen, the lower LED display screen  22  required to be maintained may be easily taken down from the corresponding frame  21  and taken out from the plurality of display assemblies  20 . Therefore, the LED display screen  22  required to be maintained is easy to repair. Further, in the situation that a plurality of LED display screens  22  are arranged above an LED display screen  22  required to be maintained, the lower LED display screen  22  required to be maintained may be easily replaced and repaired, an enough repair space for operation of engineering personnel is not required to be reserved at a back portion of the LED display device, and front maintenance is convenient. Moreover, repair cost may be reduced, repair efficiency may be improved, and the purpose of independently repairing a broken LED display screen  22  may be realized. Therefore, the technical solution of the embodiment may solve the problem that in the prior art, when a certain LED display screen at a lower layer is required to be repaired and replaced, all upper-layer LED display screens above the LED display screen are required to be detached, resulting in difficult repair. 
     It should be noted that the above expanded state corresponds to a state of the gas bag  30  that is inflated, and the above flat state corresponds to a state of the gas bag  30  that is deflated or gasless. 
     As shown in  FIGS.  10 ,  12  and  15   , each gas bag  30  includes a flat gas bag body  31  and a gas nozzle  32  arranged on the gas bag body  31 . When the gas bag  30  is in the expanded state, the flat gas bag body  31  is attached to an upper surface and a lower surface of corresponding adjacent frames  21  located above and below, such that the gas bag  30  may stably lift the upper frame  21  and prevent the frame  21  from falling. Moreover, compared with a spherical or elliptical gas bag, the flat gas bag body  31  is narrower and longer, and occupies less space. When the gas bag  30  is in the flat state, in order to prevent the frames  21  of the two adjacent display assemblies  20  located above and below from pressing the gas bag  30  to damage the gas bag  30 , first accommodation recesses  211  for accommodating the gas bag body  31  are provided on the frames  21  of the two adjacent display assemblies  20  located above and below, and the gas nozzle  32  passes through the frames  21 . 
     As shown in  FIGS.  1 - 5   , the LED display device further includes a gas source device  40  for supplying gas to the plurality of gas bags  30 . The gas source device  40  includes a gas pump  41  and an inflator  42 , the gas source device  40  further includes a plurality of first gas channels  431  in communication with the gas pump  41  and the inflator  42 , the plurality of first gas channels  431  are connected in parallel, the plurality of first gas channels  431  are in communication with the plurality of gas bags  30  in a one-to-one correspondence manner, and a first gate valve  44  is arranged on each of the first gas channels  431 . The gas pump  41  inflates the plurality of gas bags  30  by the plurality of first gas channels  431 , the plurality of gas bags and the plurality of first gas channels being arranged in a one-to-one correspondence manner. Each first gate valve  44  may connect or disconnect a corresponding first gas channel  431 . For a lower LED display screen  22  required to be maintained, the gas bag  30  above the frame  21  corresponding to the LED display screen  22  is required to be inflated, and at this time, all the other first gate valves  44  may be closed, and only the first gate valve  44  of the gas bag  30  corresponding to the LED display screen  22  required to be maintained is opened. If there is no power source for supplying power to the gas pump  41  due to environmental restrictions, inflation may be manually carried out by the inflator  42  without affecting repair. The first gate valve  44  may be a manual valve or an electric valve. The first gate valve  44  is preferably a ball valve. The gas source device  40  in the embodiment uses air as a conductive medium, which is environment-friendly and pollution-free. The LED display device in the embodiment uses pneumatic transmission, which effectively reduces the number of mechanisms and parts for mechanical transmission, and may reduce cost. 
     Certainly, in embodiments not shown in the figures, the gas source device may only include a gas pump, and the gas source device further include a plurality of first gas channels in communication with the gas pump. The gas source device may only include an inflator, and the gas source device further include a plurality of first gas channels in communication with the inflator. 
     As shown in  FIG.  5   , the gas source device  40  further includes an overflow gas channel in communication with any one of the first gas channels  431 , and an overflow valve  45  is arranged on the overflow gas channel. Through the arrangement of the overflow valve  45 , a preset constant gas pressure is provided to the gas source device  40 , so as to guarantee that the pressure is in a safe range, and guarantee safety of the gas pump, each first gas channel  431  and each gas bag  30 . 
     As shown in  FIG.  5   , the gas source device  40  includes a gas pump  41  and an inflator  42 . The gas pump  41  and the inflator  42  are connected in parallel, the plurality of first gas channels  431  converge at a junction, the junction is in communication with the gas pump  41  by a second gas channel  432 , and a first one-way valve  46  is arranged on the second gas channel  432 . Through the arrangement of the first one-way valve  46 , gas in the second gas channel  432  is prevented from flowing back. A third gas channel  433  is arranged between an inlet of the first one-way valve  46  and the inflator  42 , and a second one-way valve  47  is arranged on the third gas channel  433 . Through the arrangement of the second one-way valve  47 , gas in the third gas channel  433  is prevented from flowing back. A fourth gas channel  434  is arranged between the junction and an outlet of the first one-way valve  46 , and a second gate valve  48  is arranged on the fourth gas channel  434 . Through the arrangement of the second gate valve  48 , gas in the second gas channel  432  and the first gas channel  431  may be conveniently discharged after the LED display device is front-maintained. The second gate valve  48  may be a manual valve or an electric valve. The second gate valve  48  is preferably a ball valve. 
     As shown in  FIGS.  4 - 7   , the gas source device  40  in the embodiment further includes a mounting box  80  located below the support  10 , the above overflow gas channel, overflow valve  45 , second gas channel  432 , first one-way valve  46 , fourth gas channel  434 , and second one-way valve  47  are all mounted in the mounting box  80 . A gas inlet  81 , a gas outlet  82 , an inflating port  83  and a gas pump switch  84  are provided on the mounting box  80  at intervals. The second gas channel  432  is in communication with the gas inlet  81 , the fourth gas channel  434  is in communication with the gas outlet  82 , and the third gas channel  433  is in communication with the inflating port  83 . The gas pump  41  is located outside the mounting box  80 , and the gas pump  41  is connected to the gas pump switch  84 . Through the arrangement of the mounting box  80 , the gas source device  40  is more compact in structure, and convenient to carry and operate. The second gate valve  48  and the plurality of first gate valves  44  are mounted on the mounting box  80  at intervals, the second gate valve  48  is normally in a closed state, and the plurality of first gate valves  44  are normally in a closed state. 
     It should be noted that three “▪” between two first gate valves  44  in  FIG.  5    are ellipses, indicating that several first gate valves  44  are omitted. Three “▪” between two gas bags  30  in  FIG.  5    are ellipses, indicating that several gas bags  30  are omitted. 
     As shown in  FIGS.  8 - 11   , the LED display device further includes a plurality of longitudinal rods  51  arranged at intervals and a plurality of horizontal rods  52  arranged at intervals. The longitudinal rods  51  and the horizontal rods  52  are arranged in a staggered manner, there is a distance between the longitudinal rods  51  and the horizontal rods  52  in a front-back direction of support  10 , every two adjacent longitudinal rods  51  pass through one frame  21 , and every two adjacent horizontal rods  52  pass through one frame  21 . In this way, a plurality of display assemblies  20  are assembled together by the plurality of longitudinal rods  51  and the plurality of horizontal rods  52  that are arranged in a staggered manner. A movement gap in the upper-lower direction is provided between through holes of each frame  21  allowing the horizontal rods  52  to pass through and the corresponding horizontal rods  52 . Each longitudinal rod  51  pass through a plurality of display assemblies  20  arranged in a row in an up-down direction of support  10 , and each horizontal rod  52  pass through a plurality of display assemblies  20  arranged in a row in a left-right direction of support  10 . Each through hole of each frame  21  allowing the horizontal rod  52  to pass through may be a round hole or an elliptical hole having an aperture greater than an outer diameter of the horizontal rod  52 , or may be an elongated hole having a minimum aperture greater than an outer diameter of the horizontal rod  52 . The above movement gap has a diameter of 1 mm-3 mm. 
     As shown in  FIGS.  8 - 11   , first external threads are provided on portions of two ends of each longitudinal rod  51  protruding out of an upper surface and a lower surface of each of the plurality of LED display assemblies respectively, and the LED display device further includes first nuts connected to the first external threads. Second external threads are provided on portions of two ends of each horizontal rod  52  protruding out of a left surface and a right surface of each of the plurality of LED display assemblies respectively, and the LED display device further includes second nuts connected to the second external threads. When a lower LED display screen  22  is required to be repaired and replaced, the first nuts on the longitudinal rods  51  on two sides of a row where the LED display screen  22  required to be repaired is located is required to be unscrewed first, such that each frame  21  of the row where the LED display screen  22  required to be repaired is located may be loosened, and when the gas bag  30  above the LED display screen  22  required to be repaired is switched from the flat state to the expanded state, the frame  21  above the gas bag  30  may be driven to slide upwards. 
     As shown in  FIGS.  8 ,  9 ,  16  and  17   , a chute  61  is provided on one frame  21  of two adjacent frames  21  located left and right, and a slide block  62  matching the chute  61  in an inserted manner is arranged on the other frame  21  of two adjacent frames  21 . In this way, through matching between the chute  61  and the slide block  62 , one frame  21  of two adjacent frames  21  located left and right may slide upwards relative to the other frame  21 . Preferably, one chute  61  and one slide block  62  are arranged on a left side and a right side of one frame  21  for the convenience of processing and forming. In this way, the LED display device is simple in structure, and easy to mount and operate. 
     As shown in  FIGS.  9  and  13   , a second accommodation recess  212  for accommodating a ball  63  is provided on a back side of each frame  21 , and a portion of each ball  63  protruding out of an opening of the second accommodation recess  212  matches a surface of the support  10  in a contact manner. Since contact between the ball  63  and the surface of the support  10  is point-to-surface contact, a friction coefficient is small. When a gas bag  30  above a LED display screen  22  required to be repaired is switched from the flat state to the expanded state, only a small support force is required to be provided by the gas bag  30  to lift the frame  21  above the gas bag  30 , such that all the frames  21  above the gas bag  30  may slide upwards, which is easy and labor-saving. It should be noted that more than half of the ball  63  is located in the second accommodation recess  212 , so as to prevent the ball  63  from being separated from the second accommodation recess  212  from a back side of the corresponding frame  21 . 
     As shown in  FIGS.  11  and  13   , a pair of limiting members  64  located on an upper side and a lower side of the ball  63  is arranged on each frame  21 , and the limiting members  64  are detachably located in the second accommodation recess  212 . The pair of limiting members  64  limit the upper side and the lower side of the ball  63  respectively, and the ball  63  is only allowed to roll in the second accommodation recess  212 , such that when the frame  21  slides upwards or downwards, the ball  63  is prevented from moving upwards or downwards, and a working position of the ball  63  in the second accommodation recess  212  is prevented from changing. Specifically, there are two balls  63  arranged in the second accommodation recess  212  at an interval in the upper-lower direction on each frame  21 . In this way, the frame  21  may stably slide upwards conveniently. The limiting members  64  in the embodiment are preferably bolts, and heads of the bolts are located in the second accommodation recesses  212 , so as to prevent the situation that the heads of the bolts are in contact with the surface of the support  10 , so as to interfere with the surface of the support. 
     Specifically, as shown in  FIGS.  9 - 12  and  17   , each frame  21  includes a top beam and a bottom beam that may be oppositely spliced, and a first side beam and a second side beam that may be spliced between the top beam and the bottom beam, the top beam, the bottom beam, the first side beam and the second side beam defining a rectangular structure. The chutes  61  and the slide blocks  62  are arranged on the first side beams and the second side beams, and the chutes  61  on the first side beams are located outside the frames  21 , and the slide blocks  62  on the second side beams are located outside the frames  21 . Second accommodation recesses  212  are provided on the first side beams and the second side beams, and in order to conveniently mount the balls  63  in the second accommodation recesses  212 , two ends of the second accommodation recess  212  on each first side beam extend to an upper surface and a lower surface of the first side beam respectively, and two ends of the second accommodation recess  212  on each second side beam extend to an upper surface and a lower surface of the second side beam respectively. 
     As shown in  FIGS.  10 - 14   , the LED display device further includes a plurality of fasteners  71  penetrating the support  10 . One corresponding frame  21  is adjustably mounted on the support  10  by each fastener  71 . In order to create a movement space for the fastener  71  in an upper-lower direction, avoiding holes  11  allowing the fasteners  71  to pass through are provided on the support  10 , and each avoiding hole  11  has an aperture greater than an outer diameter of each fastener  71 . Through the provision of the avoiding holes  11 , the fasteners  71  may slide up and down with the frames  21  when the frames  21  slide up and down. Connecting holes  213  tightly connected to the fasteners  71  are provided on the frames  21 , and the LED display device further includes a plurality of damping members  72 , the damping members  72  and the fasteners  71  are arranged in a one-to-one correspondence manner, and the damping members  72  are located between the avoiding holes  11  and heads of the fasteners  71 , such that the fasteners  71  may swing up and down in the avoiding holes  11  when the frames  21  slide up and down. Through the arrangement of the damping members  72 , the heads of the fasteners  71  may be conveniently pressed on the support  10 , such that the fasteners  71  are tightly connected in the connecting holes  213 , and the frames  21  are adjustably fixed on the support  10 . 
     As shown in  FIGS.  13  and  14   , the fasteners  71  include screw heads  711  and screw rods  712  connected to the screw heads  711 . The connecting holes  213  are screw holes connected to the screw rods  712 , the avoiding holes  11  include elongated hole sections  111  for avoiding the screw rods  712  and reamed hole sections  112  for accommodating the screw heads  711 , and each reamed hole section  112  has an aperture greater than a maximum value of apertures of the elongated hole sections  111 . Through the arrangement of the elongated hole sections  111 , the avoiding holes  11  may conveniently avoid the screw rods  712 , such that the screw rods  712  may swing up and down in the avoiding holes  11  when the frames  21  slide up and down. Step surfaces are formed between the reamed hole sections  112  and the elongated hole sections  111 , the damping members  72  include springs sleeving the screw rods  712 , and the springs are located between the screw heads  711  and the step surfaces. The screw heads  711  and the step surfaces limit the springs, such that the springs may always apply elastic forces to the fasteners  71 . With the elastic forces of the springs, the gaps between the balls  63  and the support  10  may be eliminated, such that the balls  63  are tightly pressed on the surface of the support  10  in a front-back direction of the support  10 . In this way, in the situation that the frames  21  are fixed on the support  10  by the fasteners  71 , when the gas bag  30  above the LED display screen  22  required to be repaired is switched from the flat state to the expanded state, the gas bag  30  may also lift the frame  21  above the gas bag  30 , such that all the frames  21  above the gas bag  30  may slide upwards. 
     As shown in  FIGS.  13  and  14   , in the embodiment, the LED display device further includes washers  73  sleeving the fasteners  71 , and the washers  73  are located between the screw heads  711  and the springs. In this way, through the arrangement of the washers  73 , pressing forces applied to the springs by the fasteners  71  may be increased, such t-ZQShat adjustable fixation by the fasteners  71  is more reliable. 
     In the description of the disclosure, it should be understood that orientation or positional relations indicated by orientation words such as “front, back, upper, lower, left and right”, “horizontal, vertical, perpendicular to and parallel with”, and “top and bottom” are generally based on orientation or positional relations shown in the accompanying drawings, and are merely for the convenience of describing the disclosure and simplifying the description. Unless otherwise stated, these orientation words do not indicate or imply that devices or elements indicated thereby must have specific orientations or be constructed and operated in specific orientations, and therefore cannot be construed as limiting the protection scope of the disclosure. Orientation words “inside and outside” refer to an inside and an outside relative to an outline of each component. 
     For ease of description, spatial relative terms such as “on”, “above”, “on an upper surface” and “upper” can be used herein to describe spatial positional relations of one device or feature with other devices or features as shown in the figures. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientations of the devices described in the figures. For example, if the device in the figures is inverted, the device described as “above” or “on” other devices or structures would then be positioned “below” or “under” the other devices or structures. Thus, the illustrative term “above” can include two orientations of “above” and “below.” The device can also be positioned in other different ways (being rotated by 90 degrees or being positioned at other orientations), and the spatial relative description used herein is interpreted accordingly. 
     In addition, it should be noted that the use of the terms “first”, “second”, etc. to define parts is merely for convenience of distinguishing corresponding parts. Unless otherwise stated, the above words do not have special meanings, and therefore cannot be understood as limiting the protection scope of the disclosure. 
     What is described above is merely preferred embodiments of the disclosure, and is not used to limit the disclosure, and for those skilled in the art, the disclosure can be variously modified and changed. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the disclosure should fall within the protection scope of the disclosure.