Patent Publication Number: US-2021168947-A1

Title: Display device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority of Chinese Patent Application No. 201911222953.1, filed on Dec. 3, 2019, the content of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure generally relates to the field of display technology and, more particularly, relates to a display device. 
     BACKGROUND 
     With the development of flexible screens, various folding display devices have emerged. The folding of the flexible screen may be implemented by a hinge. For example, the flexible screen may be attached to a support plate with the hinge. When folding the flexible screen by expanding and contracting the hinge, the flexible screen and the hinge are separated from each other to certain extent without tight attachment. As a result, creases may be formed in the flexible screen and the performance of the flexible screen may be undesirable. 
     SUMMARY 
     One aspect of the present disclosure provides a display device. The display device includes a flexible screen, including a first main body, a second main body, and a third main body, where the third main body, between the first main body and the second main body, is connected to each of the first main body and the second main body. The display device further includes a support structure, including a first support portion and a second support portion, where the first support portion is configured to support the first main body, and the second support portion is configured to support the second main body. The display device further includes a foldable structure, where the foldable structure overlaps the third main body; the first support portion and the second support portion are connected to each other through the foldable structure; a working state of the display device includes a folding state, and the first main body overlaps the second main body in the folding state; and during a folding process of the display device, at least a portion of the foldable structure is in contact with the third main body and configured to roll relative to the third main body. 
     Other aspects of the present disclosure can be understood by those skilled in the art in light of the description, the claims, and the drawings of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following drawings are merely examples for illustrative purposes according to various disclosed embodiments and are not intended to limit the scope of the present disclosure. Drawings incorporated in the specification and forming a part of the specification demonstrate embodiments of the present disclosure and, together with the specification, describe the principles of the present disclosure. 
         FIG. 1  illustrates a structural schematic of an existing flexible display device in a folding state; 
         FIG. 2  illustrates a stereoscopic view of a display device in an unfolded state according to the embodiments of the present disclosure; 
         FIG. 3  illustrates a side view of a display device in a folding state according to the embodiments of the present disclosure; 
         FIG. 4  illustrates a side view of a display device in an unfolded state according to the embodiments of the present disclosure; 
         FIG. 5  illustrates another side view of a display device in an unfolded state according to the embodiments of the present disclosure; 
         FIG. 6  illustrates a schematic of a display device in an unfolded state T 1  according to the embodiments of the present disclosure; 
         FIG. 7  illustrates a schematic of a display device in a folding state T 2  according to the embodiments of the present disclosure; 
         FIG. 8  illustrates a schematic of a display device in a folded state T 3  according to the embodiments of the present disclosure; 
         FIG. 9  illustrates a schematic of a display device in an unfolded state T 1  according to the embodiments of the present disclosure; 
         FIG. 10  illustrates an exploded structural schematic of a display device according to the embodiments of the present disclosure; 
         FIG. 11  illustrates a structural schematic of the display device shown in  FIG. 11 ; 
         FIG. 12  illustrates a partial cross-sectional view of the display device shown in  FIG. 11  along a direction M 1 -M 2 ; 
         FIG. 13  illustrates a partial cross-sectional view of the display device shown in  FIG. 11  along a direction N 1 -N 2 ; 
         FIG. 14  illustrates a schematic of a relative positional relationship between an attaching portion and a first main body in a display device according to the embodiments of the present disclosure; 
         FIG. 15  illustrates an enlarged view of a region S in  FIG. 8 ; and 
         FIG. 16  illustrates another schematic of a foldable structure in a display device according to the embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The “first”, “second” and the like in the specification and claims of the present disclosure and the above-mentioned drawings may be used to distinguish different objects and may not be used to describe specific orders. Furthermore, the term “include” and any variations thereof may be intended to cover non-exclusive inclusion. For example, a process, a method, a system, a product, or a device containing a series of steps or units may not be limited to the listed steps or units, but also may optionally include steps or units which are not listed, or also optionally include other steps or units inherent to the process, the method, the product, or the device. 
     Reference to “embodiment” herein may indicate that a particular feature, a structure, or a characteristic described in connection with the embodiment may be included in at least one embodiment of the present disclosure. The appearances of such phrase in various places in the specification may not be necessarily all referring to a same embodiment, nor an independent or alternative embodiment that are mutually exclusive with other embodiments. It should be clearly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments. 
     The term “and/or” in the specification may merely be an association relationship describing associated objects, which may indicate that three relationships may exist. For example, A and/or B may indicate that there are three cases including A alone, A and B, and B alone. In addition, the character “/” in the specification, unless otherwise specified, may indicate an “or” relationship of related objects. 
     It should be understood that the preferred embodiments described below may merely be used to illustrate and explain the present disclosure and may not be intended to limit the present disclosure. And in the case of no conflict, the embodiments in the present disclosure and the features in the embodiments may be combined with each other. In addition, the shapes and sizes of each component in the drawings do not reflect actual proportions, and the purpose may merely be illustrating the present disclosure. 
     In order to better understand the above-mentioned technical solutions, the technical solutions of the present disclosure may be described in detail through the drawings and specific embodiments hereinafter. It should be understood that the embodiments of the present disclosure and specific features in the embodiments are detailed descriptions of the technical solutions of the present disclosure, rather than limiting the technical solutions of the present disclosure. In the case of no conflict, the embodiments of the present disclosure and the technical features in the embodiments may be combined with each other. 
       FIG. 1  illustrates a structural schematic of an existing flexible display device in a folding state. For example, a flexible screen  1  may be attached to a support plate  3  disposed with a hinge  2 . When the flexible screen  1  is folded, the hinge  2  may expand and contract, thus the flexible screen  1  and the hinge  2  may be separated from each other to certain extent without tight attachment. As a result, creases may be formed in the flexible screen, and the performance of the flexible screen may be undesirable. 
     The embodiments of the present disclosure provide a display device, as shown in  FIG. 2  to  FIG. 4 .  FIG. 2  illustrates a stereoscopic view of the display device in an unfolded (e.g., unbent) state according to the embodiments of the present disclosure.  FIG. 3  illustrates a side view of a display device in the folding state according to the embodiments of the present disclosure.  FIG. 4  illustrates a side view of the display device in the unfolded state according to the embodiments of the present disclosure. In an implementation process, the display device may be any product or component having a display function, such as a mobile phone (shown in  FIG. 2 ), a tablet computer, a television, a display, a notebook computer, a digital phone frame, a navigator, a watch, and the like. 
     In the embodiments of the present disclosure, as shown in  FIG. 2  to  FIG. 4 , the display device may include a flexible screen  10 , and the flexible screen  10  may include a first main body  101 , a second main body  102 , and a third main body  103 . The third main body  103  between the first main body  101  and the second main body  102 , may be connected to each of the first main body  101  and the second main body  102 . In an implementation process, the first main body  101 , and the second main body  102 , and the third main body  103  may be obtained by dividing a complete flexible screen, as shown in  FIG. 2 . In practical applications, the areas occupied by the first main body  101 , the second main body  102 , and the third main body  103  on the flexible screen  10  may be other circumstances, which may not be limited herein according to the embodiments of the present disclosure. Furthermore, the first main body  101 , the second main body  102 , and the third main body  103  may respectively correspond to independent flexible screens. 
     In the embodiments of the present disclosure, the display device may further include a support structure  20 , and the support structure  20  may include a first support portion  201  and a second support portion  202 . The first support portion  201  may be configured to support the first main body  101 , and the second support portion  202  may be configured to support the second main body  102 . In an implementation process, the first support portion  201  may be attached to the first main body  101 , and the second support portion  202  may be attached to the second main body  102 . In such way, in the process of folding the first main body  101  relative to the second main body  102 , the first support portion  201  may be relatively folded relative to the second support portion  202 , thereby implementing the movement synchronization of the main bodies and corresponding support portions. 
     In the embodiments of the present disclosure, the display device may further include a foldable structure  30 . The foldable structure  30  may overlap the third main body  103 . The first support portion  201  and the second support portion  202  may be connected through the foldable structure  30 . A working state of the display device includes a folding state, and the first main body  201  overlaps the second main body  202  in the folding state. During a folding process of the display device, the first support portion  201  may be folded relative to the second support portion  202  through the foldable structure  30 , and at least a portion of the foldable structure  30  may be in contact with the third main body  103  and also roll relative to the third main body  103 . In an implementation process, the foldable structure  30 , the first support portion  201 , and the second support portion  202  may be on a same side of the flexible screen  10 ; the foldable structure  30  may be disposed in a region corresponding to the region of the third main body  103 ; and the foldable structure  30  may overlap the third main body  103 . In addition, the foldable structure  30  may be connected to the first support portion  201  and the second support portion  202 , respectively. Therefore, when any support portion is folded, folding of the corresponding main body may be driven by the foldable structure  30 , thereby improving the performance of the flexible screen  10 . 
     Furthermore, during the folding process of the display device, the first support portion  201  may be folded relative to the second support portion  202  through the foldable structure  30 , and at least a portion of the foldable structure  30  may be in contact with the third main body  103  and also roll relative to the third main body  103 . That is, in the process of folding the first main body  101  and the second main body  102  of the flexible screen  10 , the first support portion  201  and the second support portion  202  may be simultaneously folded with corresponding main bodies through the foldable structure  30 . In addition, during the complete folding process, at least a portion of the foldable structure  30  may be in contact with the third main body  103  and also roll relative to the third main body  103 , that is, the friction between contact portions of the foldable structure  30  and the third main body  103  may be rolling friction, and the interaction force between the contact portions may be relatively small. Therefore, the foldable structure  30  may be ensured to protect the third main body  103  while supporting the third main body  103 . At least a portion of the foldable structure  30  may always be in contact with the third main body  103  and also roll relative to the third main body  103  during the complete folding process, thus the flexible screen  10  may be effectively protected while avoiding the creases of the flexible screen  10 . 
     In the embodiments of the present disclosure, the first main body  101  may be slidably connected to the first support portion  201 , and the second main body  102  may be fixedly connected to the second support portion  202 . In such way, during the folding process of the first main body  101  relative to the second main body  102 , the first main body  101  may slide relative to the first support portion  201 , thereby ensuring folding flexibility between the first main body  101  and the second main body  102  during the folding process of the flexible screen  10 , reducing tensile stress received by the flexible screen  10  during the folding process, and improving the performance of the display device. 
     In the embodiments of the present disclosure,  FIG. 5  illustrates a side view of the display device in the unfolded state according to the embodiments of the present disclosure. For example, the foldable structure  30  may include an axle  301  and an axle sleeve  302  surrounding the axle  301 . The first support portion  201  and the second portion  202  may be connected through the axle  301 . During the folding process of the display device, at least a portion of the axle sleeve  302  may be in contact with the third main body  103  and also roll relative to the third main body  103 . In such way, when the first main body  101  is folded relative to the second main body  102 , at least a portion of the axle sleeve  302  may always be in contact with the third main body  103  and also roll relative to the third main body  103 , thereby effectively supporting the third main body  103  by the axle sleeve  302 . Furthermore, the friction between the axle sleeve  302  and the third main body  103  may be rolling friction due to the rolling of the axle sleeve  302 , thereby effectively protecting the third main body  103 , improving the service life of the flexible screen  10 , and improving the performance of the display device. 
     In an implementation process, the connection manners between the first support portion  201  and the second support portion  202  may be various. Any one of the first support portion  201  and the second support portion  202  may be fixedly connected to the axle  301 , and the other support portion may be rotatably connected to the axle  301 . In an implementation process, the second support portion  202  may be fixedly connected to the axle  301 , and the first support portion  201  may be rotatably connected to the axle  301 . Both the first support portion  201  and the second support portion  202  may also be connected to the axle  301 . Therefore, while the relative rotation between the first support portion  201  and the second support portion  202  may be implemented through the axle  301 , the flexible rotation between the first main body  101  and the second main body  102  may be implemented, thereby ensuring the folding flexibility between the first main body  101  and the second main body  102 . Obviously, in practical applications, the connection manners between the first support portion  201 , the second support portion  202 , and the axle  301  may also be selected according to application scenarios, which may not be limited herein according to the embodiments of the present disclosure. 
     In the embodiments of the present disclosure, the axle  301  and the axle sleeve  302  may be sleeved together through a clearance fit. That is, for the fit manner, the outer diameter of the axle  301  is less than the outer diameter of the axle sleeve  301 , and a clearance is between the axle  301  and the axle sleeve  302 . In such way, during the folding process of the first main body  101  relative to the second main body  102 , the axle sleeve  302  may roll freely relative to the axle  301 , thereby ensuring the relative rolling between the axle sleeve  302  and the third main body  103 , and protecting the flexible screen  10  from damage during the folding process. 
     In the embodiments of the present disclosure, the axle  301  may be made of a material including at least one of stainless steel, chromium carbide, high manganese steel, tungsten carbide, alumina ceramic, and nylon; and/or the axle sleeve  302  may be made of a material including at least one of stainless steel, chromium carbide, high manganese steel, tungsten carbide, alumina ceramic, and nylon. 
     In an implementation process, the materials of the axle  301  and the axle sleeve  302  may be the same or different. When the axle  301  is made of a material including at least one of stainless steel, chromium carbide, high manganese steel, tungsten carbide, alumina ceramic, and nylon, the axle  301  may be a structure with high hardness and desirable abrasion resistance, thereby increasing the folding number of the foldable structure  30 , and improving the service life of the display device while ensuring the performance of the foldable structure  30 . Furthermore, when the axle sleeve  302  is made of a material including at least one of stainless steel, chromium carbide, high manganese steel, tungsten carbide, alumina ceramic, and nylon, the axle sleeve  302  may be a structure with high hardness and desirable abrasion resistance, thereby increasing the folding number of the foldable structure  30  is used, and improving the service life of the display device while ensuring the performance of the foldable structure  30 . In addition, in practical applications, the materials corresponding to the axle  301  and the axle sleeve  302  may also be selected according to application scenarios of the foldable structure  30 , which may not be limited herein according to the embodiments of the present disclosure. 
     In the embodiments of the present disclosure, as shown in  FIG. 6  to  FIG. 8 ,  FIG. 6  illustrates a schematic of the display device in an unfolded state T 1 ;  FIG. 7  illustrates a schematic of the display device in a folding state T 2 ; and  FIG. 8  illustrates a schematic of the display device in a folded (e.g., close) state T 3 . In an implementation process, the first support portion  201  may include a support element  2011  and a sliding element  2012 . The sliding element  2012  may be fixedly connected to first main body  101  and slidably connected to the support element  2011 . When the first support portion  201  is folded relative to the second support portion  202  through the foldable structure  30 , the sliding element  2012  may slide relative to the support element  2011  along a first direction, where the first direction may be a direction perpendicular to the folding axis where the first main body  101  is folded relative to the second main body  102 . 
     In an implementation process, when the first main body  101  is folded relative to the second main body  102 , the first main body  101  may drive the sliding element  2012  to slide relative to the support element  2011 , thereby ensuring the folding performance of the flexible screen  10 . For example, when the first support portion  201  is folded relative to the second support portion  202  through the foldable structure  30 , the sliding element  2012  may slide relative to the support element  2011  along the first direction, where the first direction may be a direction perpendicular to the folding axis where the first main body  101  is folded relative to the second main body  102 . In practical applications, the folding axis may be an extending direction along the central axis of the axle  301  or may be an extending direction along the central axis of the axle sleeve  302 . The first direction may be a direction shown by an arrow X in  FIG. 7 . With reference to  FIGS. 6-8 , for example, when the flexible screen  10  is folded from the unfolded state T 1  where an included angle between the first main body  101  and the second main body  102  is 180° to the folded state T 3  where an included angle between the first main body  101  and the second main body  102  is 0°, the sliding element  2012  may slide relative to the support element  2011  along the direction shown by the arrow X. For example, when the display device is at the unfolded state T 1  shown in  FIG. 6 , a distance between the end of the sliding element  2012  close to the foldable structure  30  and the axle sleeve  302  may be d 1 ; when the display device is folded from the unfolded state T 1  shown in  FIG. 6  to the folding state T 2  shown in  FIG. 7 , a distance between the end of the sliding element  2012  close to the foldable structure  30  and the axle sleeve  302  may be d 2 ; when the display device is folded from the folding state T 2  shown in  FIG. 7  to the folded state T 3  shown in  FIG. 8 , a distance between the end of the sliding element  2012  close to the foldable structure  30  and the axle sleeve  302  may be d 3 , where d 1 &gt;d 2 &gt;d 3 . In an implementation process, the folding performance of the display device may be ensured by the slide connection of the sliding element  2012  relative to the support element  2011 . In an implementation process, if the flexible screen  10  is folded from the folded state T 3  where the included angle between the first main body  101  and the second main body  102  is 0° to the unfolded state T 1  where the included angle between the first main body  101  and the second main body  102  is 180°, that is, if the display device is folded from the folded state T 3  shown in  FIG. 8  to the unfolded state T 1  shown in  FIG. 6 , at this point, the first direction may be a direction opposite to the X direction shown in  FIG. 7 . In the embodiments of the present disclosure, the folded state T 3  where the included angle between the first main body  101  and the second main body  102  is 0° may mainly, unless otherwise specified, refer to that the flexible screen  10  is flipped out. 
     In the embodiments of the present disclosure,  FIG. 9  illustrates another schematic of the display device in the unfolded state Ti. For example, the first support portion  201  may include an elastic element  2013  which is configured to provide an elastic force to the sliding element  2012 . That is, when the first support portion  201  is folded relative to the second support portion  202  through the foldable structure  30 , the elastic element  2013  may provide the elastic force to the sliding element  2012 . In such way, during the folding process of the flexible screen  10  from the folded state where the included angle between the first main body  101  and the second main body  102  is 0° to the unfolded state where the included angle between the first main body  101  and the second main body  102  is 180°, the elastic force provided by the elastic element  2013  may stretch the flexible screen  10 , and the third main body (e.g., the third main body  103  as shown in  FIG. 5 ) and the foldable structure  30  may not be detached and arched, thereby effectively avoiding the creases during the folding process of the flexible screen  10 , and improving the performance of the display device. Furthermore, the elastic element  2013  may be a spring in an implementation process. 
     In the embodiments of the present disclosure, as shown in  FIG. 10  and  FIG. 11 ,  FIG. 10  illustrates an exploded structural schematic of a display device, and  FIG. 11  illustrates a structural schematic of elements of the display device assembled together along the first direction X in  FIG. 10 . For example, the sliding element  2012  may include an attaching portion  20121  and a plurality of protruding portions  20122 ; the protruding portions  20122  may be fixedly connected to the attaching portion  20121  which may be a plate shape; the attaching portion  20121  may be attached to the first main body  101 ; and the protruding portions  20122  may be disposed at a side of the attaching portion  20121  away from the first main body  101 .  FIG. 10  is a structural schematic of the sliding element  2012  including two protruding portions  20122 . In an implementation process, the attaching portion  20121  and the protruding portions  20122  may be formed into a single piece and may also be a structure which is separately formed and be connected together. The attaching portion  20121  may be a plate shape, thereby effectively ensuring the sufficient attachment of the attaching portion  20121  and the first main body  101  and also ensuring the synchronous movement between the sliding element  2012  and the first main body  101 . Meanwhile, the attaching portion  20121  may provide a desirable support to the first main body  101 , which may improve the performance of the display device. 
     Referring to  FIG. 10  and  FIG. 11 , the first support portion  201  may include a plurality of fixing rods  2014  extending along the first direction X, and the fixing rods  2014  and the protruding portions  20122  may be slidably connected to each other. In an implementation process, the sliding path of the protruding portions  20122  may be limited through the plurality of fixing rods  2014  on the first support portion  201 , thereby implementing the control of the sliding path of the sliding element  2012  and improving the folding performance of the display device. Each protruding portion  20122  may be sleeved on a corresponding fixing rod  2014 , that is, the number of the protruding portions  20122  may be the same as the number of the fixing rods  2014 . As shown in  FIG. 10  and  FIG. 11 , the first support portion  201  may include  2  fixing rods  2014  and  2  protruding portions  20122 . 
     Referring to  FIG. 10  and  FIG. 11 , the connection manner between the support element  2011 , the second support portion  202 , and the axle  301  may be the following: a through hole may be disposed at the support element  2011 ; a through hole may be disposed at the second support portion  202 ; after the axle sleeve  302  is sleeved on the axle  301 , two ends of the axle  301  may sequentially pass through the through holes of the support element  2011  and the second support portion  202 , thereby implementing the connection between the support element  2011  and the second support portion  202  through the combination of the axle  301  and the through holes, and also implementing the desirable support to the flexible screen  10 . In another embodiment, one of the support element  2011  and the second support portion  202  may be disposed with a through hole, and the other one of the support element  2011  and the second support portion  202  may be disposed with a non-through opening; and the axle  301  may pass through the through hole and be inserted into the non-through opening. 
     In the embodiments of the present disclosure, the elastic element  2013  may be between the protruding portion  20122  and the foldable structure  30 . When the first main body  101  is folded relative to the second main body  102 , the elastic element  2013  between the protruding portion  20122  and the foldable structure  30  may apply an elastic force to the protruding portion  20122  along a direction away from the foldable structure  30 . Since one end of the flexible screen  10  is fixed on the second support portion  202  and the other end of the flexible screen  10  is fixed on the sliding element  2012 , the elastic force applied by the elastic element  2013  may ensure the flexible screen  10  to be at a stretched state, thereby improving the performance of the display device. 
     In an implementation process, as shown in  FIG. 11 , when the first support portion  201  is folded to the included angle of 0° relative to the second support portion  202  through the axle  301 , the first support portion  201  may be accommodated into a trench of the second support portion  202 , thereby improving the structural stability of the flexible screen  10 . 
     In the embodiments of the present disclosure, as shown in  FIGS. 10-13 ,  FIG. 12  illustrates a partial cross-sectional view along the extending direction of the fixing rod  2014  in  FIG. 11  (i.e., a direction shown by M 1 -M 2  in  FIG. 11 ); and  FIG. 13  illustrates a partial cross-sectional view along the protruding portion  20122 , and also along a direction perpendicular to the extending direction of the fixing rod  2014  (i.e., a direction shown by N 1 -N 2  in  FIG. 11 ). 
     In the embodiments of the present disclosure,  FIG. 14  illustrates a schematic of a relative positional relationship between the attaching portion  20121  and the first main body  101  in the display device. For example, the length of the attaching portion  20121  along a second direction may be greater than or equal to the length of the first main body  101  along the second direction. In such way, the first support portion  201  may be completely attached to the attaching portion  20121  of the first main body  101  through the attaching portion  20121 , and also may effectively support the first main body  101 , thereby improving the performance of the display device. In addition, the length of the attaching portion  20121  along the first direction may be less than the length of the first main body  101  along the first direction. The second direction may be in parallel with the plane of the first main body  101 ; the second direction may be perpendicular to the first direction; and the first direction may be a direction perpendicular to the folding axis where the first main body  101  is folded relative to the second main body  102 . In such way, when the first main body  101  is folded relative to the second main body  102 , sufficient space may be reserved for the attaching portion  20121 , thus the sliding element  2012  may not collide with the foldable structure  30  when the sliding element  2012  slides relative to the support element  2011 , thereby ensuring the folding performance of the display device and improving the service life of the display device. In addition, when the first main body  101  is completely attached to the second main body  102  (i.e., the display device is in a closed state), the attaching portion  20121  may be as close to the foldable structure  30  as possible, thereby ensuring the sufficient support of the first support portion  201  to the first main body  101  and also ensuring the performance of the display device. As shown in  FIG. 14 , the first direction may be the direction perpendicular to the extending direction of the central axis of the axle  301 , such as the direction shown by the arrow X, and the second direction may be a direction perpendicular to the first direction, such as the direction shown by the arrow Y. For example, when the length of the attaching portion  20121  along the direction Y is a, the length of the main body  101  along the direction Y is b, the length of the attaching portion  20121  along the direction X is c, and the length of the main body  101  along the direction X is d, a≥b, and c&lt;d. As shown in  FIG. 14 , a&gt;b and c&lt;d. For example, the relative positional relationship between the attaching portion  20121  and the first main body  101  along the direction X may be that a side  20121 ′ of the attaching portion  20121  facing away from the foldable structure  30  may be disposed as coplanar with a side  101 ′ of the first main body  101  facing away from the foldable structure  30 . At this point, the distance between a side of the attaching portion  20121 , adjacent to the foldable structure  30 , and the foldable structure  30  may be greater than or equal to a preset distance; and the preset distance may be a maximum distance between the attaching portion  20121  and the foldable structure  30  when the flexible screen  10  is at the unfolded state T 1 , thereby ensuring the free folding of the flexible screen  10 . 
     In the embodiments of the present disclosure, as shown in  FIGS. 10-13 , a through hole  201220  may be disposed at the protruding portion  20122  and pass through the protruding portion  20122  along the first direction (the direction shown by the arrow X), and the fixing rod  2014  may pass through the through hole  201220  of the protruding portion  20122 . That is, the fixing pod  2014  may pass through the through hole  201220  at the protruding portion  20122  of the sliding element  2012 , thereby ensuring the free sliding of the sliding element  2012  on the fixing rod  2014 . In addition, the elastic element  2013  may be sleeved on the fixing rod  2014 ; the elastic element  2013  may always be between a first support element  20111  and the protruding portion  20122  along the first direction X under the block action of the first support element  20111  and the protruding portion  20122 ; and the elastic element  2013  may undergo tensile deformation or compression deformation along the first direction X, and the fixing rod  2014  may restrict the elastic element  2013  from deforming in other directions. Therefore, the relative sliding between the sliding element  2012  and the support element  2011  may be controlled through the elastic element  2013 , the control of the folding degree of the first support portion  201  relative to the second support portion  202  may be implemented through the foldable structure  30 , and the effective control of the folding degree of the first main body  101  relative to the second main body  102  may be further implemented, thereby improving the performance of the display device. 
     In the embodiments of the present disclosure, the configuration of the elastic element  2013  on the first support portion  201  may have the following two cases but may not be limited to the following two cases according to the embodiments of the present disclosure. The first configuration is that the elastic element  2013  may include a first end  20131  and a second end  20132  opposite to each other along the first direction (the direction shown by the arrow X), the first end  20131  may be fixedly connected to the support element  2011 , and the second end  20132  may be fixedly connected to the protruding portion  20122 . In such way, when the first main body  101  is folded relative to the second main body  102 , the elastic element  2013  may have a certain control on the folding degree between the first main body  101  and the second main body  102 , thereby ensuring the flexible screen  10  from being damaged due to folding, and also improving the performance of the display device. 
     In the embodiments of the present disclosure, the second configuration of the elastic element  2013  on the first support portion  201  is that the elastic element  2013  may include the first end  20131  and the second end  20132  opposite to each other along the first direction X, and both the first end  20131  and the second end  20132  may be free ends. In such way, it may not be necessary to fix the two ends of the elastic element  2013 , which may simplify the manufacturing process of the display device and reduce the design cost of the display device; meanwhile, the control of the folding degree between the first main body  10  and the second main body  20  may be implemented, thereby improving the performance of the display device. In an implementation process, when the included angle between the first main body  101  and the second main body  102  is 180°, the length of the elastic element  2013  may be less than or equal to the original length of the elastic element  2013  in a free state. For example, when the included angle between the first main body  101  and the second main body  102  is 180°, if the length of the elastic element  2013  is A and the original length of the elastic element  2013  in a free state is B, then A≤B. At this point, the included angle between the first main body  101  and the second main body  102  is 180° and the elastic element  2013  may sufficiently ensure the stretch of the flexible screen  10 , thereby effectively avoiding the creases of the flexible screen  10  and improving the performance of the display device. Furthermore, the configuration of the elastic element  2013  may be designed according to actual application scenarios, which may not be limited herein according to the embodiments of the present disclosure. 
     In the embodiments of the present disclosure, as shown in  FIGS. 10-13 , the support element  2011  may have a hollowed-out region L, and the fixing rod  2014  may be at the hollowed-out region L; a side surface of the support element  2011  adjacent to the first main body  101  may be in sliding contact with a surface of the attaching portion  20121  away from the first main body  101 ; and under the action of the support force providing by the support element  2011 , the attaching portion  20121  may smoothly slide along the first direction relative to the support element  2011 . In such way, during the process that the first main body  101  drives the attaching portion to fold relative to the second main body  102 , the sliding element  2012  may slide freely relative to the support element  2011  in the hollowed-out region L, thereby improving the performance of the display device. 
     In the embodiments of the present disclosure, the fixing rod  2014  may be connected to the support element  2011  by any of an interference fit, a thread fit, or a snap fit, where the interference fit, the thread fit, and the snap fit may be used to implement the connection between the fixing rod  2014  and the support element  2011  using the manners in the existing technology. For example, the interference fit is a tight fit, and the axle diameter of the fixing rod  2014  is larger than the diameter of the support element  2011  which is matched with and connected to the fixing rod  2014 . During the connecting process, the interference fit may be performed by pushing the fixing rod  2014  into the support element  2011  using a special tool; or using the characteristics of the thermal expansion and contraction, the hole corresponding to the support element  2011  may be heated, then the support element  2011  may quickly fit onto the fixing rod  2014  while the hole diameter is enlarged, and the support element  2011  and the fixing rod  2014  may be tightly fitted after cooling and shrinking. For the thread fit, that is, the fit of internal and external threaded parts, the parameters such as the thread form, specification, and pitch of the support element  2011  may be required to be equal to the corresponding parameters of the fixing rod  2014 . For example, the internal and external threads of the support element  2011  and the fixing rod  2014  may all be triangular threads, trapezoidal threads, and the like. The sizes of the internal and external threads of the support element  2011  and the fixing rod  2014  may be the same and may not be relatively large or small. In addition, the pitches of the internal thread and the external thread of the support element  2011  and the fixing rod  2014  may be the same and may not be that one pitch is coarse, and another pitch is fine. Obviously, the fixed connection between the support element  2011  and the fixing rod  2014  may be implemented by other manners according to actual application scenarios, which may not be limited herein according to the embodiments of the present disclosure. 
     In the embodiments of the present disclosure, still in  FIG. 10  and  FIG. 11 , the support element  2011  may include the first support element  20111  and a second support element  20112 ; the first support element  20111  and the second support element  20112  may be mated with each other along the first direction (the direction shown by the arrow X); and one end  20141  of the fixing rod  2014  may be in contact with the first support element  20111 , and the other end  20142  of the fixing rod  2014  may be in contact with the second support element  20112 . In an implementation process, after disposing the fixing rod  2014 , the elastic element  2013 , and the sliding element  2012  on the first support element  20111 , the second support element  20112  and the first support element  20111  may then be mated together, thereby ensuring the structural stability of the support element  2011  and facilitating the effective installation of the sliding element  2012  on the fixing rod  2014 ; meanwhile, the hollowed-out region L may be formed at the support element  2011 . In an implementation process, the first support element  20111  and the second support element  20112  may be mated and fixed together by correspondingly disposing a fixing hole and a fixing column at the mated portion of the first support element  20111  and the second support element  20112  (i.e., sides of the two support elements) and also by correspondingly disposing fixing structures such as bolts or rivets. Obviously, the first support element  20111  and the second support element  20112  may be mated together using other fixing manners, which may not be limited herein according to the embodiments of the present disclosure. 
     In the embodiments of the present disclosure, when the included angle between the first main body  101  and the second main body  102  is 0°, a minimum distance between the sliding element  2012  and the foldable structure  30  is a first distance, and 0 mm≤the first distance≤H mm, where 0≤H≤0.5. In an implementation process,  FIG. 15  illustrates an enlarged view of a region S (area shown by a dashed box) in  FIG. 8  when the included angle between the first main body  101  and the second main body  102  is 0°, where H may be 0.5. When the included angle between the first main body  101  and the second main body  102  is 0°, that is, when the first main body  101  and the second main body  102  are nearly completely attached together, the sliding element  2012  may be close to the foldable structure  30  and also may not be in contact with the foldable structure  30  or may nearly be in contact with the foldable structure  30 , but there is no interaction between the sliding element  2012  and the foldable structure  30 . Therefore, the effective support of the sliding element  2012  to the first main body  101  in such state may be implemented, the performance of the display device may be improved while effectively protecting the flexible screen  10 . In an implementation process, the numerical range of H may be a range determined by manufacturing errors. Obviously, the actual numerical value of H may be determined according to actual application scenarios, which may not be limited herein according to the embodiments of the present disclosure. 
     In the embodiments of the present disclosure, still in  FIG. 8  and  FIG. 15 , when the included angle between the first main body  101  and the second main body  102  is 0°, the first main body  101  may overlap the second main body  102 , and the support structure  20  may be between the first main body  101  and the second main body  102 . Therefore, the effective support for the first main body  101  and the second main body  102  may be respectively implemented through the support structure  20 , and the structural stability of the display device when the included angle between the first main body  101  and the second main body  102  is 0° may be ensured, which may improve the performance of the display device. 
     In the embodiments of the present disclosure,  FIG. 16  illustrates another schematic of the foldable structure  30  in the display device. The foldable structure  30  may further include at least one damping element  303 . The damping element  303  may include a third end  3031  and a fourth end  3032  opposite to each other. The third end  3031  may be connected to the axle  301 , and the fourth end  3032  may be connected to the first support portion  201  or the second support portion  202 . In an implementation process, the damping element  303  may be a damping axle or a damping hinger. In such way, when the first main body  101  is folded relative to the second main body  102 , the rotation force of the foldable structure  30  may be attenuated to a certain extent through at least one damping element  303 , thereby effectively limiting the folding degree between the first main body  101  and the second main body  102  to a certain extent. That is, the control of the folding speed between the first main body  101  and the second main body  102  may be implemented, thereby ensuring that the flexible screen  10  is protected from being damaged during the folding process. The quantity of damping elements  303  in FIG.  16  is 1. Obviously, the corresponding quantity of damping elements and damping elements with different structures may also be selected according to the requirement of actual application scenarios, which may not be limited herein according to the embodiments of the present disclosure. 
     From the above-mentioned embodiments, it can be noted that the display device provided by the present disclosure may achieve at least the following beneficial effects. 
     The embodiments of the present disclosure provide the display device. During the folding process of the display device, the first support portion, configured to support the first main body, may be folded relative to the second support portion, configured to support the second main body, through the foldable structure which overlaps the third main body; and at least a portion of the foldable structure may be in contact with the third main body and also roll relative to the third main body during the complete folding process. That is, at least a portion of the foldable structure may always be in contact with the third main body and also roll relative to the third main body when the first main body is folded relative to the second main body. On the one hand, the foldable structure may be configured to support the third main body during the folding process of the flexible screen. On the other hand, the friction between the foldable structure and the third main body may be rolling friction, and the flexible screen is prevented from being damaged during the complete folding process, thereby preventing the flexible screen from causing creases and effectively protecting the flexible screen. 
     Although the embodiments of the present disclosure have been described, those skilled in the art may make other changes and modifications to the embodiments of the present disclosure once the basic inventive concepts are known. Therefore, the appended claims may be intended to include the embodiments of the present disclosure and also all changes and modifications that fall within the scope of the disclosure. 
     Obviously, those skilled in the art may make various modifications and variations to the disclosure without departing from the spirit and scope of this application. In such way, if the modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalent technologies, the disclosure may also intend to include such modifications and variations.