Folding device, folding shell and electronic equipment

Abstract

The invention provides a folding device which comprises a base and a rotating mechanism, the rotating mechanism comprises a rotating piece and a connecting piece, one end of the rotating piece is rotationally connected to the base, the end, away from the base, of the rotating piece is rotationally connected to the connecting piece, the rotating piece is provided with a hollow structure, and the hollow structure is arranged on the base. The hollow structure can enable the rotating piece to elastically deform when the rotating piece is subjected to external force; the hollow structure can enable the rotating piece to elastically deform to absorb energy when the rotating piece is subjected to external force, so that the connection reliability of the rotating piece and the connecting piece is improved, and the reliability of the folding device is improved. The invention further provides a folding shell provided with the folding device and electronic equipment.

Description

Technical Field

[0001] The present invention relates to the field of flexible screen supports, and particularly to a folding device for supporting a flexible screen, a folding housing provided with the folding device, and an electronic device provided with the folding housing. Background Art

[0002] At present, folding electronic products with bendable flexible display screens are becoming increasingly popular among people. The bendable flexible display screens of folding electronic products in the prior art generally use folding devices for support. In order to make folding electronic products thinner and lighter, the size of the folding devices is also becoming smaller and smaller. However, existing folding devices generally adopt a rigid design, that is, the rotating mechanism of the folding device has no elasticity. Therefore, when a folding electronic product falls, the impact energy brought by the whole machine is relatively large, and it is easy to damage the rotating mechanism. Summary of the Invention

[0003] The present application provides a folding device, a folding housing provided with the folding device, and an electronic device provided with the folding housing.

[0004] A folding device provided by the present application includes a base and a rotating mechanism. The rotating mechanism includes a rotating member and a connecting member. One end of the rotating member is rotatably connected to the base, and the end of the rotating member away from the base is rotatably connected to the connecting member. The rotating member is provided with a hollow structure, and the hollow structure enables the rotating member to elastically deform when subjected to an external force.

[0005] The present application further provides a folding housing, which includes a folding device and two frames. The rotating mechanism includes a rotating member and a connecting member. One end of the rotating member is rotatably connected to the base, and the end of the rotating member away from the base is rotatably connected to the connecting member. The rotating member is provided with a hollow structure, and the hollow structure enables the rotating member to elastically deform when subjected to an external force. The folding device is located between the two frames. The folding device includes a base and a rotating mechanism, and the two frames are respectively connected to opposite sides of the folding device.

[0006] The present application further provides an electronic device, which includes a flexible screen and a folding housing. The folding housing includes a folding device and two frames. The rotating mechanism includes a rotating member and a connecting member. One end of the rotating member is rotatably connected to the base, and the end of the rotating member away from the base is rotatably connected to the connecting member. The rotating member is provided with a hollow structure, and the hollow structure enables the rotating member to elastically deform when subjected to an external force. The folding device is located between the two frames. The folding device includes a base and a rotating mechanism, and the two frames are respectively connected to opposite sides of the folding device. The flexible screen is disposed on the folding housing.

[0007] The rotating member of the folding device of the electronic device of the present application is provided with a hollow structure, and the hollow structure enables the rotating member to elastically deform and absorb energy when subjected to an external force, so as to improve the connection reliability between the rotating member and the connecting member, and improve the reliability of the folding device. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the implementation manners will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0009] Figure 1 is a three-dimensional structural schematic diagram of an electronic device in one embodiment of the present application;

[0010] Figure 2 is Figure 1 a three-dimensional structural exploded schematic diagram of the folding housing and the flexible screen of the electronic device in;

[0011] Figure 3 is Figure 2 a three-dimensional structural exploded schematic diagram of the folding housing in;

[0012] Figure 4 is Figure 3 a three-dimensional structural schematic diagram of the folding device in;

[0013] Figure 5 is Figure 4 a three-dimensional structural exploded schematic diagram of the folding device in;

[0014] Figure 6 is Figure 5 a three-dimensional structural schematic diagram of another perspective of the folding device in;

[0015] Figure 7 is Figure 5 a three-dimensional structural schematic diagram of one of the folding assisting components in;

[0016] Figure 8 is Figure 7 a three-dimensional structural schematic diagram of another perspective of the folding assisting component in;

[0017] Figure 9 is Figure 7 a three-dimensional structural exploded schematic diagram of the folding assisting component in;

[0018] Figure 10 is Figure 8 a three-dimensional structural exploded schematic diagram of the folding assisting component in;

[0019] Figure 11 isFigure 9 Schematic diagram of the further three-dimensional structure of the base and the rotating mechanism in

[0020] Figure 12 is Figure 11 Enlarged three-dimensional structure diagram of the rotating part in

[0021] Figure 13 is Figure 12 One of the three-dimensional sectional views of the rotating part in

[0022] Figure 14 is Figure 9 Enlarged diagram of the linkage mechanism and the limit mechanism in

[0023] Figure 15 is Figure 10 Enlarged diagram of the linkage mechanism and the limit mechanism in

[0024] Figure 16 is Figure 14 Schematic diagram of the exploded three-dimensional structure of the linkage mechanism and the limit mechanism in

[0025] Figure 17 is Figure 15 Schematic diagram of the exploded three-dimensional structure of the linkage mechanism and the limit mechanism in

[0026] Figure 18 is Figure 7 One of the three-dimensional sectional views of the folding assistance component in

[0027] Figure 19 is Figure 7 Another three-dimensional sectional view of the folding assistance component in

[0028] Figure 20 is Figure 7 Another three-dimensional sectional view of the folding assistance component in

[0029] Figure 21 is Figure 1 Schematic diagram of the three-dimensional structure of the electronic device in the folded state in

[0030] Figure 22 is Figure 21 Schematic diagram of the three-dimensional structure of the folding assistance component in the folded state in

[0031] Figure 23 is Figure 22 Schematic diagram of the three-dimensional structure of the folding assistance component from another perspective in

[0032] Figure 24 is Figure 22 One of the three-dimensional sectional views of the folding assistance component in

[0033] Figure 25 is Figure 24Cross-sectional view of the folding assembly in;

[0034] Figure 26 is Figure 22 Another perspective sectional view of the folding assembly in;

[0035] Figure 27 is Figure 22 Another perspective sectional view of the folding assembly in.

[0036] Main reference numeral description:

[0037] 100, Electronic device; 20, Folding housing; 21, Frame; 211, Front; 212, Back; 214, Side; 215, End face; 216, Positioning groove; 217, Mounting part; 30, Flexible screen; 31, Bendable area; 33, Non-bendable area; 50, Folding device; 51, Folding assist component; 52, Bendable mechanism; 521, Middle support member; 5210, First support plate; 5211, Back; 5212, First connection area; 523, Side support member; 5230, Second support plate; 5231, Back; 5232, Second connection area; 5233, First connection part; 5234, Rotation groove; 5236, Second connection part; 5237, Adjustment groove; 5237a, First positioning section; 5237b, Second positioning section; 528, Back cover; 5282, Connection part; 5284, Connection column; 54, Base; 540, Receiving groove; 541, First housing; 5412, Positioning column; 5414, First receiving groove; 542, Arc groove; 543, Positioning hole; 544, Second housing; 5442, Positioning hole; 5444, Second receiving groove; 545, Shaft hole; 546, Connection hole; 547, Fixing hole; 55, Rotating mechanism; 550, Rotating part; 5504, First connection cylinder; 551, Rotating shaft; 552, First rotating part; 5522, Arc track; 553, Second rotating part; 5531, Lug; 554, Hollow structure; 5541, First hollow groove; 5542, Second hollow groove; 5544, Third hollow groove; 5546, Fourth hollow groove; 555, Connecting piece; 5550, First guide chute; 5551, Second guide chute; 5552, Receiving groove; 5556, Rotating track; 556, Second connection cylinder; 557, Connection part; 56, Linkage mechanism; 561, Rotating shaft; 5610, Shaft body; 5612, Connection cap; 5613, Positioning part; 5616, Card slot; 562, First link member; 5620, First guide rail; 5632, Second sleeve; 5633, Second link; 5634, Second shaft hole; 5638, Second adjustment shaft; 5622, First sleeve; 5623, First link; 5624, First shaft hole; 5626, First limiting surface; 5627, Second limiting surface; 563, Second link member; 5630, Second guide rail; 564, Gear assembly; 5642, Synchronous gear; 5643, First driving gear; 5644, Rotating shaft; 5645, Second driving gear; 5646, Gear ring; 565, Fixing piece; 5652, First guide hole; 5654, First shaft hole; 5656, Positioning part; 5657, Positioning rod; 5765, Second guide hole; 57, Limiting mechanism; 572, Pushing member; 5720, First cam; 5720a, First protruding part; 5720b, First recessed part; 5722, Second cam; 5722a, Second protruding part; 5722b, Second recessed part; 573, Holding member; 5730, Third cam;5732, connecting part; 5734, third protruding part; 5735, third recessed part; 5736, second shaft hole; 575, elastic part; 576, positioning part; 5761, sliding part; 5763, positioning part; 5765, second guiding slide hole; 5766, avoidance hole; 5768, first anti-sliding part; 577, friction assembly; 5770, first friction part; 5772, first positioning hole; 5774, second anti-sliding part; 5775, second friction part; 5776, second positioning hole; 5778, fourth anti-sliding part; 5779, buckle; 578, gasket; 5782, through hole; 5784, third anti-sliding part.; Detailed implementation manners

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0039] In addition, the descriptions of the following embodiments refer to the attached drawings for exemplifying specific embodiments in which the present application can be implemented. The directional terms mentioned in the present application, such as "upper", "lower", "front", "rear", "left", "right", "inner", "outer", "side", etc., only refer to the directions of the attached drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the present application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present application.

[0040] In the description of the present application, it should be noted that, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "set on..." should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0041] Please refer to Figures 1 to 8, the electronic device 100 in one embodiment of the present invention includes a folding housing 20 and a flexible screen 30 disposed on the folding housing 20. The folding housing 20 includes two frames 21 and a folding device 50 disposed between the two frames 21. The two frames 21 are respectively connected to opposite sides of the folding device 50, and the flexible screen 30 is disposed on the front surfaces of the two frames 21 and the folding device 50. The flexible screen 30 includes a bendable region 31 corresponding to the folding device 50 and two non-bendable regions 33 connected to opposite sides of the bendable region 31. The folding device 50 is used to support the bendable region 31 of the flexible screen 30, and the flexible screen 30 can be bent or flattened along with the folding device 50. The bendable region 31 can be bent into a U shape, a water droplet shape, or other shapes. In this embodiment, the bendable region 31 can be bent into a water droplet shape. The folding device 50 includes a folding assistance component 51 and a bendable mechanism 52 connected to the folding assistance component 51. The folding assistance component 51 includes a base 54, a rotation mechanism 55, a linkage mechanism 56, and a limit mechanism 57; the rotation mechanism 55 includes a rotating member 550 and a connecting member 555. One end of the rotating member 550 is rotatably connected to the base 54, and the opposite end of the rotating member 550 is rotatably connected to the connecting member 555 through a rotating shaft 551. The rotating member 550 is provided with a hollow structure 554, which enables the rotating member 550 to elastically deform when subjected to an external force, so as to absorb the impact energy of the external force, improve the connection reliability between the rotating member 550 and the connecting member 555, and thus improve the reliability of the folding device 50 and the electronic device 100. In this embodiment, rotation mechanisms 55 are respectively provided on opposite sides of the base 54. One end of the rotating member 550 of one rotation mechanism 55, which is away from the corresponding connecting member 555, is rotatably connected to one side of the base 54, and one end of the rotating member 550 of the other rotation mechanism 55, which is away from the corresponding connecting member 555, is rotatably connected to the opposite side of the base 54.The linkage mechanism 56 includes a pair of rotatable shafts 561 spaced parallel to each other, a first link member 562, a second link member 563, and a gear assembly 564. The pair of rotatable shafts 561 are rotatably connected to one end of the base 54. The first link member 562 is connected to one of the rotatable shafts 561, the second link member 563 is connected to the other rotatable shaft 561, the gear assembly 564 is disposed between the first link member 562 and the second link member 563, and the first link member 562 and the second link member 563 are slidably connected to the two rotating mechanisms 55 respectively. The gear assembly 564 includes a synchronous gear 5642, a first driving gear 5643, and a second driving gear 5645. The first driving gear 5643 is disposed on the first link member 562 and meshes with the synchronous gear 5642, and the second driving gear 5645 is disposed on the second link member 563 and meshes with the synchronous gear 5642. The limiting mechanism 57 includes a pushing member 572, a holding member 573, an elastic member 575, a positioning member 576 connected to the pair of rotatable shafts 561, and a friction assembly 577 disposed on the first link member 562. The pushing member 572, the holding member 573, the elastic member 575, the positioning member 576, and the friction assembly 577 are sleeved on the rotatable shaft 561, and the opposite ends of the elastic member 575 are elastically abutted against the holding member 573 and the positioning member 576 respectively. When the first link member 562 and / or the second link member 563 rotate about the axis of the corresponding rotatable shaft 561, the first driving gear 5643 and / or the second driving gear 5645 drive the synchronous gear 5642 to rotate, so that the first link member 562 and the second link member 563 rotate synchronously relative to the base 54, so as to realize the synchronous rotation of the two rotating mechanisms 55 relative to the base 54. That is, when one of the rotating mechanisms 55 or both rotating mechanisms 55 rotate relative to the base 54, the first link member 562 and the second link member 563 rotate along the axis of the two rotatable shafts 561 respectively, so that the pushing member 572 rotates relative to the holding member 573, and the frictional torque between the pushing member 572 and the holding member 573, as well as the frictional resistance of the friction assembly 577, position the first link member 562, the second link member 563, and the two rotating mechanisms 55 relative to the base 54.

[0042] The folding assistance assembly 51 is disposed on the back of the foldable mechanism 52. The foldable mechanism 52 folds or unfolds along with the folding assistance assembly 51. The frictional torque between the pushing member 572 and the holding member 573, as well as the frictional resistance of the friction assembly 577, position the foldable mechanism 52 during the folding or unfolding process, so as to position the two frames 21 relative to the base 54 at a specific angle, so that the electronic device 100 has a hovering effect.

[0043] Such as Figures 3 - 6As shown, the number of the folding assisting components 51 on the back of the foldable mechanism 52 is at least one. In this embodiment, the number of the folding assisting components 51 is three. Two of the folding assisting components 51 are respectively arranged at two opposite ends on the back of the foldable mechanism 52, and the other folding assisting component 51 is arranged in the middle of the back of the foldable mechanism 52. In other embodiments, the number of the folding assisting components 51 is two, and the two folding assisting components 51 are respectively arranged at two opposite ends on the back of the foldable mechanism 52.

[0044] In this embodiment, the "front face" refers to the face with the same light-emitting surface orientation as that of the flexible screen 30, and the "back face" refers to the face with the light-emitting surface orientation opposite to that of the flexible screen 30. The "specific angle" refers to the angle between the front faces of the two frames 21 within the range of 0 degrees to 180 degrees. The electronic device 100 is, for example, but not limited to, a mobile phone, a tablet computer, a display, a liquid crystal panel, an OLED panel, a television, a smart watch, a VR head-mounted display, an in-vehicle display, or any other product and component with a display function. The "connection" in the description of the embodiments of the present invention includes both direct connection and indirect connection. For example, the connection between A and B includes the direct connection between A and B or the connection through a third element C or more other elements. The connection also includes two cases of integrated connection and non-integrated connection. The integrated connection means that A and B are integrally formed and connected, and the non-integrated connection means that A and B are non-integrally formed and connected.

[0045] A hollow structure 554 is provided on the rotating member 550 of the folding device 50 of the electronic device 100 of the present invention, so that the rotating member 550 can elastically deform and absorb energy when subjected to an external force, improving the connection reliability between the rotating member 550 and the connecting member 555, and improving the reliability of the folding device 50 and the electronic device 100. When folding or unfolding, one of the rotating mechanisms 55 drives the first link member 562 to rotate around the corresponding rotating shaft 561, and the other rotating mechanism 55 drives the second link member 563 to rotate around the corresponding rotating shaft 561. The pushing members 572 on the first link member 562 and the pushing members 572 on the second link member 563 respectively rotate relative to the holding member 573, so that the frictional torque between the pushing member 572 and the holding member 573, and at the same time, the friction assembly 577 also has a frictional resistance, so that the first link member 562, the second link member 563 and the rotating mechanism 55 are positioned relative to the base 54, so as to position the foldable mechanism 52, realize the relative positioning of the two frames 21 to a specific angle, and realize a better hovering effect of the electronic device 100.

[0046] As Figure 2 and Figure 3As shown, the housing 21 includes a front surface 211, a back surface 212, opposite side surfaces 214, and opposite end surfaces 215. A positioning groove 216 is provided on the side of the front surface 211 close to the folding device 50. The opposite ends of the positioning groove 216 extend respectively close to the two side surfaces 214, and one side of the positioning groove 216 penetrates through the end surface 215 facing the folding device 50; mounting portions 217 are provided at the opposite ends and the middle of the housing 21 at the positioning groove 216. Optionally, functional modules such as a battery, a PCB assembly, a speaker, a receiver, and keys are provided inside the housing 21.

[0047] As Figures 4 - 6 As shown, the bendable mechanism 52 includes a middle support member 521 and two side support members 523 connected to opposite sides of the middle support member 521. One side support member 523 is movably connected to three rotating mechanisms 55 and three first link members 562 on one side of the folding device 50, and the other side support member 523 is movably connected to three rotating mechanisms 55 and three first link members 562 on the opposite side of the folding device 50; the back surface of the flexible screen 30 is attached to the front surfaces of the middle support member 521 and the side support members 523. One rotating mechanism 55 rotates relative to the base 54, and drives the other rotating mechanism 55 to rotate synchronously relative to the base 54 through the linkage mechanism 56, so as to realize the synchronous unfolding or synchronous bending of the bendable mechanism 52. During the folding or unfolding of the folding device 50, the two rotating mechanisms 55 of each folding assist assembly 51 rotate synchronously relative to the base 54 respectively, the first link member 562 and the second link member 563 rotate synchronously relative to the base 54 respectively, and at the same time the first link member 562 and the second link member 563 slide relative to the two rotating mechanisms 55 respectively. The first driving gear 5643 on the first link member 562 and the second driving gear 5645 on the second link member 563 rotate respectively around the axes of the two rotating shafts 561, so as to rotate the synchronous gear 5642; the frictional torque between the pushing member 572 and the holding member 573 and the frictional resistance of the friction assembly 577 can position the side support member 523 relative to the middle support member 521, so as to position the two housings 21 relative to each other at a specific angle.

[0048] The middle support member 521 includes a strip-shaped first support plate 5210 and a back cover 528 connected to the back surface of the first support plate 5210. The first support plate 5210 includes a front surface and a back surface 5211 facing away from the front surface. A first connection area 5212 for positioning on the front surface of the folding assist assembly 51 is provided on the back surface 5211 of the first support plate 5210. In this embodiment, first connection areas 5212 are respectively provided at opposite ends of the back surface 5211 of the first support plate 5210. Opposite ends of each first support plate 5210 are respectively connected to two adjacent folding assist assemblies 51. Each side support member 523 includes a strip-shaped second support plate 5230 and a second connection area 5232 provided on the back surface 5231 of the second support plate 5230. In this embodiment, two second connection areas 5232 are provided on the back surface 5231 of the second support plate 5230, and the two second connection areas 5232 are located at opposite ends of the back surface 5231 of the second support plate 5230. Each second connection area 5232 includes a pair of first connection portions 5233 and a second connection portion 5236 spaced apart from each other. The first connection portions 5233 are provided on the side away from the middle support member 521, and the second connection portion 5236 is provided between the pair of first connection portions 5233. A pair of arc-shaped rotation grooves 5234 are provided on each pair of first connection portions 5233, and the axis lines of the pair of rotation grooves 5234 are collinear. An arc-shaped adjustment groove 5237 is provided on the second connection portion 5236, and the middle of the adjustment groove 5237 bends toward the side away from the second support plate 5230. The adjustment groove 5237 includes a first positioning section 5237a and a second positioning section 5237b at its opposite ends, and the first positioning section 5237a is closer to the middle support member 521 than the second positioning section 5237b. The back cover 528 is a strip-shaped frame, and connection portions 5282 are respectively provided at opposite ends and the middle of the front surface of the back cover 528. The bases 54 of the three folding assist assemblies 51 are respectively connected to the three connection portions 5282 of the back cover 528, and the connection portions 5282 include a plurality of connection columns 5284.

[0049] Please also refer to Figures 7 - 13, the rotating member 550 includes a first rotating portion 552, a second rotating portion 553, and a connecting portion 557 connected between the first rotating portion 552 and the second rotating portion 553. The first rotating portion 552 is provided at the first end of the rotating member 550, and the second rotating portion 553 is provided at the opposite second end of the rotating member 550. The first rotating portion 552 is rotatably connected to the base 54 through the cooperation of an arc rail and an arc groove. The axis line of the arc groove is collinear with the rotation axis line between the rotating member 550 and the base 54. The arc groove is provided in one of the base 54 and the first rotating portion 552, and the arc rail is provided in the other of the base 54 and the first rotating portion 552. In this embodiment, receiving grooves 540 are respectively provided on the opposite sides of the front surface of the base 54 for respectively receiving the first rotating portions 552 of the two rotating members 550. Arc grooves 542 are respectively provided on the two inner side surfaces of the receiving groove 540 of the base 54 opposite to each other. The two arc grooves 542 on the same side of the base 54 are coaxial. The opposite ends of the arc groove 542 respectively penetrate through the front surface of the base 54. Arc rails 5522 are respectively provided on the opposite end surfaces of the first rotating portion 552. The two arc rails 5522 are coaxial. When the first rotating portion 552 is received in the corresponding receiving groove 540, the two arc rails 5522 are respectively rotatably received in the two arc grooves 542.

[0050] Optionally, the hollow structure 554 includes a first hollow groove 5541 provided on the first rotating portion 552. The length direction of the first hollow groove 5541 is parallel to the axial direction of the arc rail 5522. When the rotating member 550 is subjected to an external force impact, the first rotating portion 552 can elastically deform to absorb energy, reduce the impact on the rotating shaft 551 and the connecting member 555, so as to enhance the connection reliability between the rotating member 550 and the connecting member 555, and at the same time enhance the reliability of the folding device 50 and the electronic device 100. Specifically, a plurality of first hollow grooves 5541 are provided in the middle of the first rotating portion 552, and the length direction of each first hollow groove 5541 is parallel to the axial direction of the arc rail 5522. The plurality of first hollow grooves 5541 can make the first rotating portion 552 elastically deform more easily. When the first rotating portion 552 is subjected to an external force impact, it can elastically deform to absorb the energy of the external force impact, can avoid the damage of the folding device 50, so as to improve the reliability of the folding device 50, and facilitate the installation of the first rotating portion 552 and the connecting member 555. Specifically, the plurality of first hollow grooves 5541 are arranged along the direction perpendicular to the axis of the arc rail 5522. The opposite ends of each first hollow groove 5541 are respectively close to the opposite ends of the first rotating portion 552, and the opposite sides of each first hollow groove 5541 respectively penetrate through the opposite side surfaces of the first rotating portion 552. Preferably, the plurality of first hollow grooves 5541 are arranged at equal intervals along the direction perpendicular to the axial direction of the arc rail 5522.

[0051] Optionally, the second rotating part 553 is rotatably connected to the connecting part 555 through the rotating shaft 551. The connecting part 557 is connected between the first rotating part 552 and the second rotating part 553. The hollow structure 554 further includes a second hollow groove 5542 provided on the connecting part 557. The second hollow groove 5542 can enable the connecting part 557 to deform when subjected to an external impact and absorb the energy of the external impact, avoiding damage to the folding device 50 and improving the reliability of the folding device 50. Specifically, a plurality of second hollow grooves 5542 spaced apart from each other are provided in the middle of the connecting part 557. The length direction of each second hollow groove 5542 is parallel to the length direction of the first hollow groove 5541, and the plurality of second hollow grooves 5542 are arranged along the axis direction perpendicular to the arc track 5522. Further, the plurality of second hollow grooves 5542 are evenly spaced along the axis direction perpendicular to the arc track 5522. The opposite sides of the second hollow groove 5542 respectively penetrate through the opposite side surfaces of the connecting part 557. The opposite ends of the second hollow groove 5542 are respectively close to the opposite ends of the connecting part 557, and the length of the second hollow groove 5542 is less than or equal to the length of the first hollow groove 5541.

[0052] Optionally, the hollow structure 554 further includes a third hollow groove 5544 provided on the connecting part 557. A third hollow groove 5544 is provided between every two adjacent second hollow grooves 5542. The opposite ends of the third hollow groove 5544 are respectively close to the opposite ends of the connecting part 557. The opposite sides of the third hollow groove 5544 respectively penetrate through the opposite side surfaces of the connecting part 557. The length direction of the third hollow groove 5544 is parallel to the length direction of the second hollow groove 5542, and the length of the third hollow groove 5544 is greater than the length of the second hollow groove 5542. Further, the plurality of third hollow grooves 5544 are arranged along the axis direction perpendicular to the arc track 5522.

[0053] Optionally, the hollow structure 554 further includes fourth hollow grooves 5546 provided on the opposite end surfaces of the connecting part. A fourth hollow groove 5546 is provided between every two adjacent third hollow grooves 5544. The length direction of the fourth hollow groove 5546 is parallel to the length direction of the third hollow groove 5544.

[0054] Optionally, the rotating member 550 can be made by 3D printing to form a first hollow groove 5541, a second hollow groove 5542, a third hollow groove 5544 and a fourth hollow groove 5546 on the rotating member 550, realizing the hollowing of the rotating member 550, so that the rotating member 550 can elastically deform when impacted by an external force and absorb the impact energy. The base 54 includes a first body 541 and a second body 544 connected to the first body 541; specifically, the first body 541 and the second body 544 are snap-connected through the cooperation of a positioning post and a positioning hole. The positioning post is provided on one of the first body 541 and the second body 544, and the positioning hole is provided on the other of the first body 541 and the second body 544; in this embodiment, a positioning post 5412 is provided on the side of the first body 541 facing the second body 544, and a positioning hole 5442 is provided on the side of the second body 544 facing the first body 541; on the front side of the first body 541 near the second body 544, first receiving grooves 5414 are respectively provided at opposite ends, and on the front side of the second body 544 near the first body 541, second receiving grooves 5444 are respectively provided at opposite ends; when the first body 541 is connected to the second body 544, the first receiving groove 5414 and the second receiving groove 5444 on the same side of the base 54 enclose a receiving groove 540. An arc groove 542 is provided at the end face of each first receiving groove 5414 of the first body 541, and the axes of the two arc grooves 542 are spaced parallel; an arc groove 542 is provided at the end face of each second receiving groove 5444 of the second body 544, and the axes of the two arc grooves 542 are spaced parallel. A positioning hole 543 is provided on the front surface of the base 54, and the locking member passes through the positioning hole 543 and is locked to the back cover so that the base 54 is fixedly connected to the back cover. On the end face of the base 54 facing the linkage mechanism 56, two shaft holes 545, two connection holes 546 and a fixing hole 547 are provided. The two shaft holes 545 are located on opposite sides of the base 54, the two connection holes 546 are located between the two shaft holes 545, and the fixing hole 547 is located between the two connection holes 546. The axis lines of the two shaft holes 545 and the two connection holes 546 are parallel to the rotation axis line between the rotating member 550 and the base 54. Specifically, the two shaft holes 545, the two connection holes 546 and the fixing hole 547 are respectively provided on the end face of the second body 544 facing away from the first body 541.

[0055] In some embodiments, the arc groove 542 on the base 54 and the arc track 5522 on the first rotating part 552 can be interchanged. Specifically, arc tracks are respectively provided on the two inner side surfaces of the receiving groove 540 of the base 54 that are opposite to each other, and the two arc tracks on the same side of the base 54 share the same axis line; arc grooves are respectively provided on the opposite sides of the first rotating part 552, and the two arc grooves share the same axis line; when the first rotating part 552 is received in the corresponding receiving groove 540, the two arc tracks can be rotatably received in the two arc grooves respectively.

[0056] One end of the second rotating part 553 away from the first rotating part 552 is rotatably connected to the corresponding connecting part 555 through a rotating shaft 551 at the first end of the connecting part 555. One ends of the first connecting rod 562 and the second connecting rod 563 away from the base 54 are respectively slidably connected to the second ends of the two connecting parts 555. Specifically, the second rotating part 553 is provided with a lug 5531 at the end away from the first rotating part 552, and the first end of the connecting part 555 is provided with a receiving groove 5552. The lug 5531 is rotatably received in the receiving groove 5552. The rotating part 550 further includes a first connecting cylinder 5504 away from the base 54. Specifically, the first connecting cylinder 5504 is provided at the end of the lug 5531 facing away from the first rotating part 552. The connecting part 555 includes a second connecting cylinder 556 provided at its first end. The receiving groove 5552 penetrates the second connecting cylinder 556 along the radial direction of the second connecting cylinder 556. The first connecting cylinder 5504 and the second connecting cylinder 556 are mutually embedded so that the first connecting cylinder 5504 and the second connecting cylinder 556 are coaxial. The rotating shaft 551 penetrates the inner cavities of the first connecting cylinder 5504 and the second connecting cylinder 556.

[0057] As Figures 6 - 10 shown, one end of the first connecting rod 562 away from the base 54 is slidably connected to one end of the corresponding connecting part 555 through the cooperation of a first guide chute and a first guide rail. The first guide chute extends along a direction perpendicular to the rotation axis of the rotating part 550 and the base 54. The first guide chute is provided on one of the first connecting rod 562 and the corresponding connecting part 555, and the first guide rail is provided on the other of the first connecting rod 562 and the corresponding connecting part 555. In this embodiment, the second end of the connecting part 555 on one side of the base 54 is provided with a first guide chute 5550, and the first connecting rod 562 is provided with a first guide rail 5620 slidably penetrating the first guide chute 5550. One end of the second connecting rod 563 away from the base 54 is slidably connected to one end of the corresponding connecting part 555 through the cooperation of a second guide chute and a second guide rail. The second guide chute extends along a direction perpendicular to the rotation axis of the rotating part 550 and the base 54. The second guide chute is provided on one of the second connecting rod 563 and the corresponding connecting part 555, and the second guide rail is provided on the other of the second connecting rod 563 and the corresponding connecting part 555. The second end of the connecting part 555 on the opposite side of the base 54 is provided with a second guide chute 5551, and the second connecting rod 563 is provided with a second guide rail 5630 slidably penetrating the second guide chute 5551.

[0058] As Figures 3 - 8As shown, the connecting member 555 is rotatably connected to the corresponding side support member 523 through the cooperation of a rotating groove and a rotating rail. The rotating groove is provided on one of the side support member 523 and the connecting member 555, and the rotating rail is provided on the other of the side support member 523 and the connecting member 555. In this embodiment, rotating rails 5556 are respectively provided at opposite ends of the connecting member 555, and the two rotating rails 5556 are respectively rotatably received in two rotating grooves 5234, so that the side support member 523 is rotatably connected to the connecting member 555.

[0059] In some embodiments, rotating grooves are respectively provided at opposite ends of the connecting member 555, and the side support member 523 is provided with rotating rails corresponding to the rotating grooves of the connecting member 555. The rotating rails are rotatably received in the corresponding rotating grooves, so that the side support member 523 is rotatably connected to the connecting member 555.

[0060] Please refer to Figures 7 - 10 and Figures 14 - 17 , the rotating shaft 561 includes a shaft body 5610 and a connecting cap 5612 located at one end of the shaft body 5610. A positioning portion 5613 is provided near the connecting cap 5612 of the shaft body 5610. One rotating shaft 561 is fixedly connected to the first link member 562 through its positioning portion 5613, and the other rotating shaft 561 is fixedly connected to the second link member 563 through its positioning portion 5613. In this embodiment, the positioning portion 5613 is a positioning groove provided on the outer wall of the shaft body 5610 and extending along the axial direction of the shaft body 5610. The connecting cap 5612 is used for rotatably connecting to the base 54; a clamping groove 5616 is provided at the end of the shaft body 5610 away from the connecting cap 5612, and the clamping groove 5616 is located on the outer peripheral wall of the shaft body 5610 and surrounds the shaft body 5610 in a circumferential direction.

[0061] The first connecting rod 562 further includes a first sleeve 5622 and a first connecting rod 5623. The first connecting rod 5623 is connected to the outer peripheral wall of the first sleeve 5622. The first sleeve 5622 can be sleeved on the positioning portion 5613 of the shaft body 5610. Specifically, the first sleeve 5622 has a non-circular first shaft hole 5624. After the rotating shaft 561 is inserted into the first shaft hole 5624 of the first sleeve 5622, the first sleeve 5622 can be positioned on the positioning portion 5613. The first sleeve 5622 and the rotating shaft 561 can rotate together along the axis of the rotating shaft 561. The first driving gear 5643 is arranged on the outer peripheral wall of the first sleeve 5622. The first driving gear 5643 is located on the side of the first sleeve 5622 away from the first connecting rod 5623, and the axis center line of the first driving gear 5643 is colinear with the axis center line of the first sleeve 5622. In this embodiment, the rotation angle of the teeth of the first driving gear 5643 arranged along the circumference of the first sleeve 5622 is 180 degrees. The first connecting rod 562 and the corresponding side support member 523 are movably connected through the adjustment groove and the first adjustment shaft, and the axis of the first adjustment shaft is parallel to the axis of the rotating shaft 561; the adjustment groove is provided in one of the side support member 523 and the first connecting rod 562, and the first adjustment shaft is provided in the other of the side support member 523 and the first connecting rod 562. In this embodiment, the side support member 523 is provided with an adjustment groove, and the first adjustment shaft 5628 is provided at one end of the first connecting rod 5623 of the first connecting rod 562 away from the rotating shaft 561, and the first adjustment shaft 5628 is rotatably and slidably penetrated in the adjustment groove. The first guide rails 5620 are respectively protruded on the opposite sides of the first connecting rod 5623, and the first guide rails 5620 extend along the length direction of the first connecting rod 5623.

[0062] The second link member 563 further includes a second sleeve 5632 and a second link 5633. The second link 5633 is connected to the outer peripheral wall of the second sleeve 5632, and the second sleeve 5632 can be sleeved on the positioning portion 5613 of the shaft body 5610. Specifically, the second sleeve 5632 has a non-circular second shaft hole 5634. After the rotating shaft 561 is inserted into the second shaft hole 5634, the second sleeve 5632 is positioned on the positioning portion 5613. The second driving gear 5645 is provided on the side of the second sleeve 5632 away from the second link 5633, and the axis line of the second driving gear 5645 is collinear with the axis line of the second sleeve 5632. In this embodiment, the rotation angle of the teeth of the second driving gear 5645 arranged along the circumferential direction of the second sleeve 5632 is 180 degrees. The second link member 563 and the corresponding side support member 523 are movably connected through the cooperation of the adjustment groove and the second adjustment shaft. The axis line of the second adjustment shaft is parallel to the axis line direction of the rotating shaft 561; the adjustment groove is provided on one of the side support member 523 and the second link member 563, and the second adjustment shaft is provided on the other of the side support member 523 and the second link member 563. In this embodiment, the side support member 523 is provided with an adjustment groove, and one end of the second link 5633 away from the rotating shaft 561 is provided with a second adjustment shaft 5638. The second adjustment shaft 5638 is rotatably and slidably inserted into the adjustment groove. Second guide rails 5630 are respectively convexly provided on opposite sides of the second link 5633, and the second guide rails 5630 extend along the length direction of the second link 5633.

[0063] The pushing member 572 includes a first cam 5720 and a second cam 5722. The first cam 5720 is provided at one end of the first sleeve 5622, and the second cam 5722 is provided at one end of the second sleeve 5632. The first cam 5720 and the first sleeve 5622 share the same axis, and the second cam 5722 and the second sleeve 5632 share the same axis. The first cam 5720 is provided at the end of the first sleeve 5622 away from the first driving gear 5643, and the second cam 5722 is provided at the end of the second sleeve 5632 away from the second driving gear 5645. The first cam 5720 and the second cam 5722 are on the same side. Optionally, the first cam 5720 includes a circular sleeve and a concave-convex surface. The sleeve is connected to the end of the first sleeve 5622, and the sleeve and the first sleeve 5622 share the same axis. The concave-convex surface is provided at one end of the sleeve facing away from the first sleeve 5622. The concave-convex surface includes a first protruding portion 5720a and a first recessed portion 5720b, and the first protruding portion 5720a and the first recessed portion 5720b are arranged at intervals in sequence along the circumferential direction of the sleeve. The number of the first protruding portions 5720a and the number of the first recessed portions 5720b can be set as required. For example, the first cam 5720 can include one first protruding portion 5720a and one first recessed portion 5720b, two first protruding portions 5720a and two first recessed portions 5720b, three first protruding portions 5720a and three first recessed portions 5720b, or four first protruding portions 5720a and four first recessed portions 5720b, etc. Optionally, the second cam 5722 includes a circular sleeve and a concave-convex surface. The sleeve is connected to the end of the second sleeve 5632, and the sleeve and the second sleeve 5632 share the same axis. The concave-convex surface is provided at one end of the sleeve facing away from the second sleeve 5632. The concave-convex surface includes a second protruding portion 5722a and a second recessed portion 5722b, and the second protruding portion 5722a and the second recessed portion 5722b are arranged at intervals in sequence along the circumferential direction of the sleeve. The number of the second protruding portions 5722a and the number of the second recessed portions 5722b can be set as required. For example, the second cam 5722 can include one second protruding portion 5722a and one second recessed portion 5722b, two second protruding portions 5722a and two second recessed portions 5722b, three second protruding portions 5722a and three second recessed portions 5722b, or four second protruding portions 5722a and four second recessed portions 5722b, etc.

[0064] The synchronous gear 5642 includes a rotating shaft 5644 and a gear ring 5646. The gear ring 5646 is fixedly sleeved on the rotating shaft 5644, and the opposite ends of the rotating shaft 5644 respectively extend out of the opposite ends of the gear ring 5646. In this embodiment, the gear assembly 564 includes a pair of mutually meshing synchronous gears 5642, wherein one synchronous gear 5642 meshes with the first driving gear 5643, and the other synchronous gear 5642 meshes with the second driving gear 5645. The diameter of the pitch circle of the gear ring 5646 is smaller than the diameters of the pitch circles of the first driving gear 5643 and the second driving gear 5645, and the number of teeth around the synchronous gear 5642 in one circle is less than the number of teeth around the first driving gear 5643 and the second driving gear 5645 in one circle. Under a certain width and height space of the rotating shaft 561, the diameters of the pitch circles of the first driving gear 5643 and the second driving gear 5645 are increased by the two synchronous gears 5642 arranged between the two rotating shafts 561, so that the outer diameters of the first cam 5720 and the second cam 5722 can be increased.

[0065] The linkage mechanism 56 further includes a fixing member 565 which is connected to one end of two rotating shafts 561, and a positioning member 576 which is connected to the opposite ends of the two rotating shafts 561; the fixing member 565 is a rectangular positioning piece, and the opposite ends of the fixing member 565 are respectively provided with first sliding guide holes 5652, and the opposite ends of the positioning member 576 are respectively provided with second sliding guide holes 5765. The shaft bodies 5610 of the two rotating shafts 561 are respectively inserted through the two first sliding guide holes 5652 and the two second sliding guide holes 5765. The rotating shaft 561 can rotate in the first sliding guide hole 5652 and the second sliding guide hole 5765, and the fixing member 565 and the positioning member 576 can only slide along the axial direction of the two rotating shafts 561. Two spaced first shaft holes 5654 are provided between the two first sliding guide holes 5652 in the middle of the fixing member 565, and the axis line of the first sliding guide hole 5652 is parallel to the axis line of the first shaft hole 5654. A positioning portion 5656 is provided on the side of the fixing member 565 facing the first link member 562. The first link member 562 includes a first limiting surface 5626 and a second limiting surface 5627; when the first link member 562 and the second link member 563 are in a folded state relative to the base 54, the positioning portion 5656 abuts against the first limiting surface 5626; when the first link member 562 and the second link member 563 are in a flattened state relative to the base 54, the positioning portion 5656 abuts against the second limiting surface 5627. Specifically, a notch is provided around the shaft hole 5624 at the end of the first sleeve 5622 away from the pushing member 572, and the first limiting surface 5626 and the second limiting surface 5627 are respectively the opposite end faces of the notch. The first limiting surface 5626 is farther from the guide rail 5620 than the second limiting surface 5627; the positioning portion 5656 is a positioning block. A positioning rod 5657 is provided on the side of the fixing member 565 away from the positioning portion 5656, and the positioning rod 5657 is used for positioning on the base 54. The opposite end faces of the fixing member 565 are set as arc surfaces.

[0066] Please refer to Figures 16 - 17, the abutting member 573 includes two third cams 5730 and a connecting bar 5732. The two third cams 5730 are located at opposite ends of the abutting member 573, and the connecting bar 5732 is connected between the two third cams 5730. The two third cams 5730 are respectively slidably sleeved on a pair of rotating shafts 561, and the two third cams 5730 are respectively rotatably engaged with the first cam 5720 and the second cam 5722. The rotating shaft 561 can rotate relative to the abutting member 573, and the abutting member 573 can slide along the axial direction of the rotating shaft 561. Specifically, the third cam 5730 includes a circular sleeve and a concave-convex surface provided at one end of the sleeve. The concave-convex surface includes a third protrusion 5734 and a third recess 5735, and the third protrusion 5734 and the third recess 5735 are arranged at intervals in sequence along the circumferential direction of the sleeve. The number of the first recesses 5720b and the number of the first protrusions 5720a on the first cam 5720 are the same as the number of the third protrusions 5734 and the number of the third recesses 5735 on one of the third cams 5730, so that the first protrusion 5720a cooperates with the third recess 5735, and the third protrusion 5734 cooperates with the first recess 5720b. The number of the second recesses 5722b and the number of the second protrusions 5722a on the second cam 5722 are the same as the number of the third protrusions 5734 and the number of the third recesses 5735 on the other third cam 5730, so that the second protrusion 5722a cooperates with the third recess 5735, and the third protrusion 5734 cooperates with the second recess 5722b. The abutting member 573 is provided with a second shaft hole 5736. Specifically, the connecting bar 5732 is provided with two second shaft holes 5736, and the axis line of the second shaft hole 5736 is parallel to the axis line of the third cam 5730. The opposite ends of the rotating shaft 5644 of the synchronous gear 5642 are respectively inserted into the first shaft hole 5654 and the second shaft hole 5736. In this embodiment, the elastic member 575 includes a spring sleeved on each rotating shaft 561.

[0067] Please refer to Figures 16 - 17 , the positioning member 576 includes a sliding portion 5761 slidably connected to a pair of rotating shafts 561 and a positioning portion 5763 connected to the sliding portion 5761. The positioning portion 5763 is located between the pair of rotating shafts 561. Specifically, the sliding portion 5761 is a rectangular sliding piece, and the positioning portion 5763 is a positioning block provided in the middle of the sliding piece. The opposite ends of the sliding piece are respectively provided with second guide holes 5765. Optionally, the opposite ends of the sliding portion 5761 are respectively provided as arc surfaces. Optionally, two avoidance holes 5766 are provided on the side of the positioning portion 5763 facing the synchronous gear 5642, and one end of the rotating shaft 5644 of the synchronous gear 5642 can be respectively inserted into the two avoidance holes 5766 of the positioning portion 5763.

[0068] As Figure 16 andFigure 17 As shown, the friction assembly 577 of the limit mechanism 57 includes a gasket 578, a friction member, and a buckle 5779. The gasket 578 is slidably sleeved on a pair of rotating shafts 561. The friction member is sleeved on the rotating shaft 561. The friction member is clamped between the gasket 578 and the positioning member 576. The friction member can rotate together with the rotating shaft 561. There is a frictional resistance between the friction member and the positioning member 576. Specifically, the friction assembly 577 includes a pair of first friction members 5770 and a pair of second friction members 5775. The pair of first friction members 5770 and the pair of second friction members 5775 are respectively sleeved on two rotating shafts 561. A pair of buckles 5779 are respectively clamped in the card slots 5616 of a pair of rotating shafts 561. The pair of first friction members 5770 are clamped by the gasket 578 and the positioning member 576. The pair of second friction members 5775 are clamped by the gasket 578 and a pair of buckles 5779. When the rotating shaft 561 rotates relative to the base 54, the first friction member 5770 and the second friction member 5775 rotate with the rotating shaft 561. There is a frictional resistance between the first friction member 5770 and the positioning member 576 and the gasket 578. There is a frictional resistance between the second friction member 5775 and the gasket 578. The buckle 5779 can be, but is not limited to, a C-shaped buckle or a U-shaped buckle, etc. The buckle 5779 is used to be clamped in the card slot 5616 of the rotating shaft 561.

[0069] Specifically, a first positioning hole 5772 is opened in the middle of the first friction member 5770. The first friction member 5770 is fixedly connected to the rotating shaft 561 through the first positioning hole 5772. A second anti-slip portion 5774 is provided on the side surface of the first friction member 5770 facing the positioning member 567 and / or a second anti-slip portion 5774 is provided on the side surface of the first friction member 5770 facing away from the positioning member 576. In this embodiment, second anti-slip portions 5774 are respectively provided on the opposite side surfaces of the first friction member 5770. The second anti-slip portion 5774 can be, but is not limited to, a rough surface, a damping layer, a plurality of small protrusions or a plurality of small concave convex portions, holes or rough surfaces provided on the first friction member 5770. Specifically, a plurality of small holes are respectively provided on the opposite side surfaces of the first friction member 5770. These small holes can increase the frictional resistance of the first friction member 5770. In this embodiment, a first anti-slip portion 5768 is provided on the side surface of the positioning member 576 facing the first friction member 5770, and a second anti-slip portion 5774 is provided on the side surface of the first friction member 5770 facing the positioning member 576. Optionally, the first anti-slip portion 5768 on the positioning member 576 can be omitted, and only the second anti-slip portion 5774 on the side surface of the first friction member 5770 facing the positioning member 576 is retained; or the second anti-slip portion 5774 on the side surface of the first friction member 5770 facing the positioning member 576 can be omitted, and only the first anti-slip portion 5768 on the positioning member 576 is retained.

[0070] ​The spacer 578 is slidably sleeved on a pair of rotating shafts 561, and the first friction member 5770 is between the spacer 578 and the positioning member 576; when the first friction member 5770 rotates with the rotating shaft 561, there is frictional resistance between the first friction member 5770 and the positioning member 576, and between the first friction member 5770 and the spacer 578. Specifically, the spacer 578 is a strip-shaped plate, and the opposite ends of the spacer 578 are respectively provided with arc surfaces. The side surface of the spacer 578 facing the first friction member 5770 is provided with a third anti-slip portion 5784. In this embodiment, through holes 5782 are respectively provided at the opposite ends of the spacer 578, and third anti-slip portions 5784 are respectively provided around each through hole 5782 on the opposite side surfaces of the spacer 578. The third anti-slip portion 5784 can be, but is not limited to, a convex portion, a hole or a rough surface provided on the spacer 578, etc. In this embodiment, the third anti-slip portion 5784 is a plurality of holes provided around each through hole 5782 on the opposite side surfaces of the spacer 578. In this embodiment, the side surface of the spacer 578 facing the first friction member 5770 is provided with a third anti-slip portion 5784, and the side surface of the first friction member 5770 facing the spacer 578 is provided with a second anti-slip portion 5774. Optionally, the third anti-slip portion 5784 on the side surface of the spacer 578 facing the first friction member 5770 can be omitted, and only the second anti-slip portion 5774 on the side surface of the first friction member 5770 facing the spacer 578 is retained; or the second anti-slip portion 5774 on the side surface of the first friction member 5770 facing the spacer 578 can be omitted, and only the third anti-slip portion 5784 on the side surface of the spacer 578 facing the first friction member 5770 is retained.

[0071] The spacer 578 abuts against the second friction member 5775. When the second friction member 5775 rotates with the rotating shaft 561, there is a frictional resistance between the second friction member 5775 and the spacer 578. Specifically, a second positioning hole 5776 is formed in the middle of the second friction member 5775. The second friction member 5775 is fixedly connected to the rotating shaft 561 through the second positioning hole 5776. A third anti-slip portion 5784 is provided on the side of the spacer 578 facing the second friction member 5775, and / or a fourth anti-slip portion 5778 is provided on the side of the second friction member 5775 facing the spacer 578. In this embodiment, the fourth anti-slip portions 5778 are respectively provided on the opposite sides of the second friction member 5775. The fourth anti-slip portion 5778 can be, but is not limited to, a convex portion, a hole, a rough surface, etc. provided on the second friction member 5775. In this embodiment, a plurality of holes are respectively provided on the opposite sides of the second friction member 5775, and these holes can increase the frictional resistance of the second friction member 5775. In this embodiment, a third anti-slip portion 5784 is provided on the side of the spacer 578 facing the second friction member 5775, and a fourth anti-slip portion 5778 is provided on the side of the second friction member 5775 facing the spacer 578. Optionally, the third anti-slip portion 5784 on the side of the spacer 578 facing the second friction member 5775 can be omitted, and only the fourth anti-slip portion 5778 on the side of the second friction member 5775 facing the spacer 578 is retained; or the fourth anti-slip portion 5778 on the side of the second friction member 5775 facing the spacer 578 can be omitted, and only the third anti-slip portion 5784 on the side of the spacer 578 facing the second friction member 5775 is retained.

[0072] Please refer to Figures 14 - 17, when assembling the linkage mechanism 56 and the limiting mechanism 57, insert the end portions of the two rotating shafts 561 away from the connecting caps 5612 into the two first guiding slide holes 5652 of the fixing member 565 respectively until the fixing member 565 abuts against the connecting caps 5612; mesh the two synchronous gears 5642 with each other and place them between the two first link members 562, and the two synchronous gears 5642 mesh with the first driving gear 5643 and the second driving gear 5645 respectively; insert the end portions of the two rotating shafts 561 away from the connecting caps 5612 into the first sleeve 5622 and the second sleeve 5632 respectively, and insert the end portions of the two rotating shafts 5644 of the gear assembly 564 close to the fixing member 565 into the two first shaft holes 5654 of the fixing member 565 respectively, and the positioning portions 5656 of the fixing member 565 are received in the notches of the corresponding first sleeves 5622; at this time, each first cam 5720 and the corresponding first driving gear 5643 share the rotating shaft 561, and each second cam 5722 and the corresponding second driving gear 5645 share the rotating shaft 561; each positioning portion 5656 is located between the corresponding first limiting surface 5626 and the second limiting surface 5627. Sleeve the abutting member 573 on the two rotating shafts 561 so that the two third cams 5730 of the abutting member 573 can be rotatably engaged with the first cam 5720 and the second cam 5722 respectively; specifically, insert the end portions of the two rotating shafts 561 provided with the card slots 5616 into the inner cavities of the two third cams 5730 of the abutting member 573 respectively, and insert the two rotating shafts 5644 into the two second shaft holes 5736 of the abutting member 573 respectively, and the two rotating shafts 5644 pass through the corresponding second shaft holes 5736 respectively; sleeve the two elastic members 575 on the two rotating shafts 561 respectively, sleeve the positioning member 576 on the two rotating shafts 561 so that the two rotating shafts 5644 are inserted into the positioning member 576 respectively, and the two elastic members 575 are clamped between the abutting member 573 and the positioning member 576; sleeve two of the first friction members 5770 on the two rotating shafts 561 respectively, sleeve the gasket 578 on the two rotating shafts 561, and then sleeve the other two second friction members 5775 on the two rotating shafts 561 respectively. At this time, the gasket 578 is located between the first friction member 5770 and the second friction member 5775, and the card slot 5616 of each rotating shaft 561 exposes the side surface of the corresponding second friction member 5775 away from the positioning member 576; then snap the two fasteners 5779 onto the card slots 5616 of the two rotating shafts 561 respectively. At this time, the two fasteners 5779 abut against the side surfaces of the two second friction members 5775 away from the positioning member 576 respectively, and the elastic members 575 are in a compressed state.

[0073] When the linkage mechanism 56 is bent from the fully flattened state, the first link member 562 is bent relative to the abutting member 573 toward the second link member 563. The first link member 562 rotates along the axis line of the corresponding rotating shaft 561 to drive the corresponding rotating shaft 561, the first driving gear 5643, and the corresponding pushing member 572 to rotate along the axis line of the rotating shaft 561. The rotating shaft 561 rotates within the corresponding second guiding hole 5765 of the positioning member 576, the corresponding first guiding hole 5652 of the fixing member 565, and the through hole 5782 of the gasket 578. The rotating first driving gear 5643 drives the second driving gear 5645 to rotate through the synchronous gear 5642. The rotation of the second driving gear 5645 drives the corresponding rotating shaft 561, the second sleeve 5632, and the second link 5633 to rotate, so that the first link member 562 and the second link member 563 of the linkage mechanism 56 approach each other synchronously. At the same time, the pushing members 572 on the first link member 562 and the pushing members 572 on the second link member 563 rotate relative to the abutting member 573 respectively, so that the first cam 5720 and the second cam 5722 respectively rotate and push the two third cams 5730. The abutting member 573 slides axially along the rotating shaft 561 to squeeze the elastic member 575. The elastic member 575 elastically pushes the positioning member 576, so that the first friction member 5770 is clamped between the gasket 578 and the positioning member 576, and the second friction member 5775 is clamped between the gasket 578 and the buckle 5779. And the first friction member 5770 and the second friction member 5775 rotate relative to the positioning member 576 and the gasket 578 along with the corresponding rotating shaft 561. During the above process, the axial forces on the first cam 5720, the corresponding third cam 5730, the corresponding first friction member 5770, and the corresponding second friction member 5775 sleeved on one of the rotating shafts 561 are equal to the elastic force of the elastic member 575; the axial forces on the second cam 5722, the corresponding third cam 5730, the corresponding first friction member 5770, and the corresponding second friction member 5775 sleeved on the other rotating shaft 561 are equal to the elastic force of the elastic member 575; the frictional torques between the first cam 5720 and the third cam 5730, between the second cam 5722 and the third cam 5730, and / or the frictional resistance of the first friction member 5770, as well as the frictional resistance of the second friction member 5775, can limit the first link member 562 and the second link member 563 at a specific angle between 180 degrees and 0 degrees. When the angle between the first link member 562 and the second link member 563 is 180 degrees, the linkage mechanism 56 is in a fully flattened state. When the angle between the first link member 562 and the second link member 563 is 0 degrees, the linkage mechanism 56 is in a fully bent state.

[0074] In other usage modes, the first link member 562 and the second link member 563 can be rotated together in opposite directions. The first link member 562 and the second link member 563 rotate respectively along the axis lines of the corresponding rotating shafts 561, so as to drive a pair of rotating shafts 561, the first driving gear 5643, the second driving gear 5645 and two pushing members 572 to rotate respectively along the axis lines of the pair of rotating shafts 561; the first driving gear 5643 and the second driving gear 5645 drive two synchronous gears 5642 to rotate together, so that the first link member 562 and the second link member 563 of the linkage mechanism 56 approach each other synchronously; at the same time, the pushing members 572 on the first link member 562 and the second link member 563 rotate relative to the abutting member 573, so that the first cam 5720 and the second cam 5722 respectively rotate and push two third cams 5730 of the abutting member 573. The abutting member 573 slides axially along the rotating shaft 561 to squeeze the elastic member 575. The elastic member 575 elastically abuts against the positioning member 576 to clamp the first friction member 5770 and the second friction member 5775, and the first friction member 5770 and the second friction member 5775 rotate relative to the positioning member 576 and the gasket 578 along with the corresponding rotating shaft 561.

[0075] When the linkage mechanism 56 is deployed from the fully bent state, the first link member 562 is deployed away from the second link member 563 relative to the abutting member 573. The first link member 562 rotates along the axis line of the corresponding rotating shaft 561 to drive the corresponding rotating shaft 561, the first driving gear 5643 and the corresponding pushing member 572 to rotate along the axis line of the rotating shaft 561. The rotating shaft 561 rotates in the first guiding slide hole 5652 corresponding to the fixing member 565, the second guiding slide hole 5765 corresponding to the positioning member 576, and the corresponding through hole 5782. The rotating first driving gear 5643 drives the second driving gear 5645 to rotate through the synchronous gear 5642. The rotation of the second driving gear 5645 drives the corresponding rotating shaft 561, the second sleeve 5632, the corresponding pushing member 572 and the second link member 5625 to rotate, so that the first link member 562 and the second link member 563 of the linkage mechanism 56 move away from each other synchronously. At the same time, the pushing members 572 on the first link member 562 and the second link member 563 rotate relative to the abutting member 573 respectively, so that the first cam 5720 and the second cam 5722 respectively rotate and push the two third cams 5730. The elastic member 575 elastically abuts between the abutting member 573 and the positioning member 576, so that the positioning member 576 slides axially along the rotating shaft 561. The first friction member 5770 is clamped between the gasket 578 and the positioning member 576, and the second friction member 5775 is clamped between the gasket 578 and the buckle 5779. The first friction member 5770 and the second friction member 5775 rotate relative to the gasket 578 and the positioning member 576 along with the corresponding rotating shaft 561. In the above process, the axial forces on the first cam 5720, the third cam 5730, the first friction member 5770 and the second friction member 5775 on one of the rotating shafts 561 are equal to the elastic force of the elastic member 575; the axial forces on the second cam 5722, the third cam 5730, the first friction member 5770 and the second friction member 5775 on the other rotating shaft 561 are equal to the elastic force of the elastic member 575; the frictional torque between the first cam 5720 and the third cam 5730, the frictional torque between the second cam 5722 and the third cam 5730, and the frictional resistance of the first friction member 5770 and the second friction member 5775 can limit the angle between the first link member 562 and the second link member 563 between 0 degrees and 180 degrees.

[0076] In other usage modes, the first link member 562 and the second link member 563 can be rotated together in directions away from each other. The first link member 562 and the second link member 563 rotate respectively along the axis lines of a pair of rotating shafts 561 to drive the pair of rotating shafts 561, the first driving gear 5643, the second driving gear 5645, and the two pushing members 572 to rotate respectively along the axis lines of the corresponding rotating shafts 561. The first driving gear 5643 and the second driving gear 5645 drive the two synchronizing gears 5642 to rotate together, so that the first link member 562 and the second link member 563 of the linkage mechanism 56 move away from each other and flatten. At the same time, the pushing members 572 on the first link member 562 and the pushing members 572 of the second link member 563 rotate relative to the holding members 573 respectively, so that the first cam 5720 and the second cam 5722 rotate and push the two third cams 5730 respectively. The holding member 573 slides axially along the rotating shaft 561 to squeeze the elastic member 575. The elastic member 575 elastically pushes the positioning member 576 so that the first friction member 5770 is clamped between the gasket 578 and the positioning member 576, and the second friction member 5775 is clamped between the gasket 578 and the buckle 5779. Moreover, the first friction member 5770 and the second friction member 5775 rotate relative to the positioning member 576 and the gasket 578 along the corresponding rotating shaft 561.

[0077] As Figures 7 - 11 and Figures 18 - 20, when assembling the folding assisting component 51, place the two first connecting cylinders 5504 of one rotating member 550 in the two receiving grooves 5552 of one connecting member 555, and place the two first connecting cylinders 5504 of the other rotating member 550 in the two receiving grooves 5552 of the other connecting member 555; pass the rotating shaft 551 through the inner cavities of the corresponding first connecting cylinders 5504 and the inner cavities of the corresponding second connecting cylinders 556, so that the rotating members 550 are respectively rotatably connected to the connecting members 555; place the first rotating portions 552 of one rotating member 550 in the receiving groove 540 on one side of the base 54, and place the first rotating portions 552 of the other rotating member 550 in the receiving groove 540 on the relatively opposite side of the base 54, so that the two arc tracks 5522 of each first rotating portion 552 are respectively rotatably received in the two arc grooves 542 of the base 54, and the positioning posts 5412 are snapped into the positioning holes 5442. Since the rotating member 550 is provided with a hollow structure 554, the principle of compressibility of the hollow structure 554 can be utilized to achieve the purpose of non - grading and clearance elimination in the assembly of the rotating member 550 and the connecting member 555 and the assembly of the rotating member 550 and the base 54, that is, the assembly clearance between the rotating member 550 and other components can be eliminated, and the weight of the rotating member 550 can be reduced, thereby reducing the overall weight of the folding device 50; place the combination of the linkage mechanism 56 and the limiting mechanism 57 between the two connecting members 555, slidably insert the first guide sliding rails 5620 of the first link member 562 into the first guide sliding grooves 5550 of one connecting member 555 respectively, and slidably insert the second guide sliding rails 5630 of the second link member 563 into the second guide sliding grooves 5551 of the other connecting member 555 respectively, so that the two connecting caps 5612, the two rotating shafts 5644 and the positioning rod 5657 are respectively inserted into the two shaft holes 545, the two connecting holes 546 and the fixing holes 547.

[0078] As Figures 3 - 8As shown, when assembling the folding assisting assembly 51 to the bendable mechanism 52, place the three folding assisting assemblies 51 on the three connecting parts 5282 of the back cover 528 respectively, place the first support plate 5210 on the base 54, and lock the fastener through the connecting hole on the first support plate 5210 and the positioning hole 543 on the base 54 to the corresponding connecting post; place the two side support members 523 on the opposite sides of the base 54, rotatably receive the two rotating rails 5556 of each connecting member 555 in the corresponding pair of rotating slots 5234 respectively, and pass the adjusting shaft 5628 of the first link member 562 through the corresponding adjusting slot 5237; make the first support plate 5210 located between the two side support members 523, and connect the two first connecting regions 5212 to the adjacent two folding assisting assemblies 51 respectively. Then connect the back cover 528 to the back surface of the first support plate 5210. The axis of rotation between the rotating member 550 and the base 54 is parallel to the axis of the rotating shaft 561, and the axis of rotation between the rotating member 550 and the connecting member 555 is parallel to the axis of the rotating shaft 561. When the two side support members 523 are in a fully flattened state, the adjusting shaft 5628 is positioned at the second positioning section 5237b of the corresponding adjusting slot 5237, and the positioning portion 5656 abuts against the second limiting surface, so that the folding device 50 is kept in a fully flattened state, and the front surfaces of the two side support members 523 and the middle support member 521 are coplanar, preventing the side support members 523 from being bent back relative to the middle support member 521. When the two side support members 523 are in a fully bent state, the adjusting shaft 5628 is positioned at the first positioning section 5237a of the corresponding adjusting slot 5237, and the positioning portion 5656 abuts against the first limiting surface, so that the folding device 50 is kept in a fully bent state, and the front surfaces of the two side support members 523 and the middle support member 521 enclose a water droplet shape, preventing the side support members 523 from being further bent relative to the middle support member 521.

[0079] Please refer to Figures 1 - 3 as well. Place the assembled folding device 50 between the two frames 21, and fixedly connect the connecting members 555 on the opposite sides of the folding device 50 to the two frames 21 respectively. At this time, the front surfaces of the two frames 21, the front surface of the middle support member 521 and the front surfaces of the two side support members 523 are coplanar. The back surface of the flexible screen 30 is connected to the front surfaces of the two frames 21 and the front surface of the folding device 50, the bendable area 31 faces the folding device 50, and the two non-bendable areas 33 face the bendable mechanisms on the front surfaces of the two frames 21 respectively.

[0080] Please refer to Figure 1 and Figures 21 to 27, when bending the electronic device 100, a bending force is applied to at least one of the two frames 21 of the electronic device 100, so that the rotating mechanism 55 connected to the two frames 21 rotates in a direction approaching each other, and the folding device 50 is bent through the two folding assisting components 51, and the foldable area 31 is bent along with the foldable mechanism 52. Specifically, if a bending force is applied to one of the frames 21, the one frame 21 drives the corresponding rotating mechanism 55 to rotate relative to the base 54 toward the side close to the flexible screen 30; so as to drive the first link member 562 or the second link member 563 to rotate relative to the base 54 toward the side close to the flexible screen 30 along the axis of the corresponding rotating shaft 561. At the same time, the first guide rail 5620 of the first link member 562 or the second guide rail 5630 of the second link member 563 slides in the first guide groove 5550 or the second guide groove 5551 of the corresponding connecting member 555, and the first sleeve 5622, the rotating shaft 561, the first driving gear 5643 and the pushing member 572 of the first link member 562 rotate along the axis of the corresponding rotating shaft 561. The rotating first driving gear 5643 drives another first driving gear 5643 to rotate through the synchronous gear 5642 gear assembly. The rotation of the second driving gear 5645 drives the corresponding rotating shaft 561, the second sleeve 5632, the pushing member 572 and the second link 5633 to rotate, so that the first link member 562 and the second link member 563 of the linkage mechanism 56 approach each other synchronously; at the same time, the first cam 5720 and the second cam 5722 respectively rotate and push the two third cams 5730, and the holding member 573 slides along the axial direction of the rotating shaft 561 to squeeze the elastic member 575. The elastic member 575 elastically pushes the positioning member 576 so that the first friction member 5770 is clamped between the gasket 578 and the positioning member 576 and the first friction member 5770 is clamped between the gasket 578 and the buckle 5779, and the first friction member 5770 and the second friction member 5775 rotate relative to the gasket 578 and the positioning member 576 along with the corresponding rotating shaft 561. During the bending process of the linkage mechanism 56, the first rotating portion 552 of the rotating member 550 rotates relative to the base 54 through the cooperation of the arc track and the corresponding arc groove, and the second rotating portion 553 of the rotating member 550 is rotatably connected to the corresponding connecting member 555 along the corresponding rotating shaft 551. The adjusting shaft 5628 rotates and slides from the second positioning section 5237b to the first positioning section 5237a in the corresponding adjusting groove 5237. The first link member 562 and the second link member 563 respectively rotate along the axis of the corresponding rotating shaft 561 and approach each other, so as to realize the mutual approach of the two side support members 523, make the folding device 50 in a bent state, and the foldable area 31 of the flexible screen 30 is bent along with the folding device 50 until the fronts of the two non-foldable areas 33 of the flexible screen 30 are mutually attached, and the foldable area 31 is bent into a water droplet shape, thus realizing the seamless folding of the electronic device 100.

[0081] During the bending process of the electronic device 100, the sum of the frictional torques between the first cam 5720 and the third cam 5730, the frictional torques between the second cam 5722 and the third cam 5730, the frictional resistance of the first friction member 5770, the frictional resistance of the second friction member 5775, and the frictional resistance between the rotating shaft 5644 can limit the rebound of the flexible screen 30, so that the side support member 523 is positioned at a specific angle relative to the middle support member 521, and the two frames 21 can be limited at a specific angle between 180 degrees and 0 degrees. When the two frames 21 are bent and limited at 0 degrees, that is, the two non-bending regions 33 of the flexible screen 30 are parallel to each other; the bendable region 31 of the flexible screen 30 is bent into a water droplet shape, reducing the duty ratio of the bendable region 31 after bending, so as to reduce the overall thickness of the electronic device 100.

[0082] In other bending methods of the electronic device 100, a bending force can also be applied to the two frames 21 at the same time. The two frames 21 respectively drive the two side support members 523 to rotate toward the side close to the flexible screen 30, and the folding device 50 is used to realize the bending of the electronic device 100.

[0083] When the electronic device 100 needs to be flattened, pull out one of the frames 21 outward, so that the two rotating mechanisms 55 connected to the two frames 21 rotate in a direction away from each other. Specifically, an outward pulling force is applied to one of the frames 21 of the electronic device 100, and the one frame 21 drives the corresponding rotating mechanism 55 to rotate relative to the base 54 to the side away from the flexible screen 30, so that the guide rail 5620 of the first link member 562 or the guide rail 5630 of the second link member 563 slides in the first guide groove 5550 or the second guide groove 5551 of the corresponding connecting member 555. The first sleeve 5622, the rotating shaft 561, the first driving gear 5643 and the pushing member 572 of the first link member 562 rotate along the axis of the corresponding rotating shaft 561. The rotating first driving gear 5643 drives the second driving gear 5645 to rotate through the synchronous gear 5642 gear assembly. The rotation of the second driving gear 5645 drives the corresponding rotating shaft 561, the second sleeve 5632, the pushing member 572 and the second link 5633 to rotate along the axis of the corresponding rotating shaft 561. The second guide rail 5630 of the second link member 563 slides in the guide groove 5550 of the corresponding connecting member 555, so that the first link member 562 and the second link member 563 of the linkage mechanism 56 move away from each other synchronously; at the same time, the first cam 5720 and the second cam 5722 rotate and push the two third cams 5730. The elastic member 575 elastically abuts between the positioning member 576 and the abutting member 573, so that the positioning member 576 slides along the axial direction of the rotating shaft 561. The first friction member 5770 is clamped between the gasket 578 and the positioning member 576, and the second friction member 5775 is clamped between the gasket 578 and the buckle 5779. The first friction member 5770 and the second friction member 5775 rotate relative to the gasket 578 and the positioning member 576 along with the corresponding rotating shaft 561; during the bending process of the linkage mechanism 56, the first rotating part 552 of the rotating member 550 rotates relative to the base 54, and the second rotating part 553 of the rotating member 550 is rotatably connected to the corresponding connecting member 555. The adjusting shaft 5628 rotates and slides in the corresponding adjusting groove 5237. The first link member 562 and the second link member 563 rotate along the axis of the corresponding rotating shaft 561 and move away from each other respectively, so as to realize the mutual separation of the two side support members 523, so that the folding device 50 is unfolded, and the foldable area 31 of the flexible screen 30 is unfolded along with the folding device 50 until the flexible screen 30 is flattened.

[0084] During the flattening process of the electronic device 100, the frictional torques between the first cam 5720 and the second cam 5722 and the two third cams 5730 respectively, the frictional torques of the first friction member 5770 and the second friction member 5775, and the frictional resistance between the rotating shaft 5644 can limit the rebound of the flexible screen 30, so that the side support member 523 is positioned at a specific angle relative to the middle support member 521, and the two frames 21 can be limited at a specific angle between 0 degrees and 180 degrees.

[0085] In other bending methods of the electronic device 100, a force that pulls the two frames 21 outward can also be applied simultaneously. The two frames 21 drive the rotating mechanisms 55 on the opposite sides of the base 54 to rotate away from each other respectively, so as to drive the first link member 562 and the second link member 563 on the opposite sides of the base 54 to rotate away from each other, causing the two side support members 523 to rotate towards the side away from the flexible screen 30, and the electronic device 100 can be unfolded through the folding device 50.

[0086] The folding device 50 of the electronic device 100 of the present invention realizes synchronous bending or unfolding through the folding assistance component 51. Since the elastic member 575 can provide a large axial force, a large frictional torque exists between the first cam 5720 and the third cam 5730, and a large frictional torque exists between the second cam 5722 and the third cam 5730. At the same time, the first friction member 5770 and the second friction member 5775 also have a large frictional resistance. Therefore, the electronic device 100 can be stably limited at a specific angle between 0 degrees and 180 degrees during bending, realizing the hovering function of the whole machine. Secondly, the rotating member 550 is provided with a hollow structure 554, so that the rotating member 550 can elastically deform. When the electronic device 100 drops, the elastic deformation of the rotating member 550 under external impact can absorb the dropping energy of the electronic device 100, avoiding damage to the folding device 50 and improving the reliability of the folding device 50 and the electronic device 100.

[0087] The above is the implementation manner of the embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the embodiments of the present invention, several improvements and retouches can be made, and these improvements and retouches are also regarded as the protection scope of the present invention.

Claims

1. A folding device, characterized in that, The folding device includes: a base; and a rotating mechanism, the rotating mechanism includes a rotating member and a connecting member, one end of the rotating member is rotatably connected to the base, the end of the rotating member away from the base is rotatably connected to the connecting member, and the rotating member is provided with a hollow structure, and the hollow structure enables the rotating member to elastically deform when subjected to an external force.

2. The folding device according to claim 1, characterized in that, The rotating member includes a first rotating portion, and the first rotating portion is rotatably connected to the base through the cooperation of an arc rail and an arc groove. The hollow structure includes a first hollow groove provided on the first rotating portion, and the length direction of the first hollow groove is parallel to the axial direction of the arc rail.

3. The folding device according to claim 2, characterized in that, A plurality of the first hollow grooves are arranged in the middle of the first rotating portion along a direction perpendicular to the axis of the arc rail. Opposite ends of each first hollow groove are respectively close to opposite ends of the first rotating portion, and opposite sides of each first hollow groove respectively penetrate opposite side surfaces of the first rotating portion.

4. The folding device according to claim 2, characterized in that, The rotating member further includes a second rotating portion and a connecting portion. The second rotating portion is rotatably connected to the connecting member, and the connecting portion is connected between the first rotating portion and the second rotating portion. The hollow structure further includes a second hollow groove provided on the connecting portion.

5. The folding device according to claim 4, characterized in that, A plurality of second hollow grooves spaced from each other are arranged in the middle of the connecting portion. The length direction of each second hollow groove is parallel to the length direction of the first hollow groove, and the plurality of second hollow grooves are arranged along a direction perpendicular to the axis of the arc rail.

6. The folding device according to claim 5, characterized in that, Opposite sides of the second hollow groove respectively penetrate opposite side surfaces of the connecting portion, and the length of the second hollow groove is less than or equal to the length of the first hollow groove.

7. The folding device according to claim 5, characterized in that, The hollow structure further includes a third hollow groove provided on the connecting portion. The third hollow groove is provided between every two adjacent second hollow grooves. Opposite ends of the third hollow groove are respectively close to opposite ends of the connecting portion. Opposite sides of the third hollow groove respectively penetrate opposite sides of the connecting portion. The length direction of the third hollow groove is parallel to the length direction of the second hollow groove, and the length of the third hollow groove is greater than the length of the second hollow groove.

8. The folding device according to claim 5, characterized in that, The hollow structure further includes fourth hollow grooves provided on opposite end surfaces of the connecting portion. The fourth hollow groove is provided between every two adjacent third hollow grooves, and the length direction of the fourth hollow groove is parallel to the length direction of the third hollow groove.

9. A folding housing, characterized in that, The folding housing includes the folding device according to any one of claims 1-8 and two frames. The folding device is located between the two frames, and the two frames are respectively connected to opposite sides of the folding device.

10. An electronic device, characterized in that, The electronic device includes a flexible screen and the folding housing according to claim 9, and the flexible screen is disposed on the folding housing.

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