Rotating shaft mechanism and foldable electronic device

Abstract

Disclosed are a rotating shaft mechanism and a foldable electronic device. The rotating shaft mechanism comprises a base (10), a support plate (70), a first swing arm (61), a second swing arm (62), and a synchronization gear (40). The synchronization gear comprises a first gear (41), a second gear (42), a third gear (43) and a fourth gear (44) which are sequentially arranged in the width direction of the base. The first gear comprises a first tooth portion (4111). The second gear comprises a second tooth portion (4211) and a third tooth portion (4212) sequentially arranged in the circumferential direction of the second gear. The radius of an addendum circle of the second tooth portion is greater than the radius of an addendum circle of the first tooth portion. The support plate is arranged on the side of the synchronization gear facing away from the base and is fixedly connected to the base, and the support plate covers the synchronization gear in the thickness direction of the base. The rotating shaft mechanism has a small size, thereby achieving the lightness and thinness of the foldable electronic device.

Description

Rotating shaft mechanism and foldable electronic device

[0001] The present application claims priority to the Chinese patent application No. 202411093715.6, filed on August 9, 2024, and entitled "Rotating shaft mechanism and foldable electronic device", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of electronic products, and in particular to a rotating shaft mechanism and a foldable electronic device. BACKGROUND

[0003] With the development of technology, the appearance (ID) form of electronic devices (such as mobile phones, tablet computers, etc.) has a trend from a straight phone to a folding phone. The folding phone has a large screen in the open state, fully meeting the visual experience of consumers, and has a small volume in the closed state, being convenient to carry. The folding phone generally needs to be provided with a synchronous structure to realize the synchronous rotation of the structures on both sides of the rotating shaft. However, the synchronous structure in the prior art occupies a large space, which is not conducive to the thinning of the electronic device. SUMMARY

[0004] The present application provides a rotating shaft mechanism and a foldable electronic device, which can reduce the space occupied by the synchronous structure in the rotating shaft mechanism, and is conducive to the thinning of the electronic device.

[0005] In a first aspect, the present application provides a rotating shaft mechanism. The rotating shaft mechanism is applied to a foldable electronic device. The foldable electronic device includes a first housing, a second housing, and a display screen. The rotating shaft mechanism is installed between the first housing and the second housing, and is fixedly connected with the first housing and the second housing. The display screen is installed on the first housing, the second housing, and the rotating shaft mechanism. The bendable part of the display screen is arranged opposite to the rotating shaft mechanism. The first housing and the second housing are relatively rotated through the rotating shaft mechanism, drive the bendable part of the display screen to bend, and make the display screen fold.

[0006] The rotating shaft mechanism includes a base, a support plate, a first rotating component, a second rotating component, and a synchronous component. The first rotating component and the second rotating component are respectively located on opposite sides of the base in the width direction, and are rotatably connected with the base. The first rotating component includes a first fixed frame, a first main swing arm, and a first door plate. One end of the first main swing arm is rotatably connected with the base, and the other end is rotatably connected with the first fixed frame. The first door plate is arranged in layers with the first fixed frame, and is rotatably connected with the first fixed frame and rotatably and slidably connected with the first main swing arm. The first fixed frame is fixedly connected with the first housing.

[0007] When the first shell rotates relative to the base, the first fixed frame is driven to rotate relative to the base, thereby driving the first main swing arm and the first door plate to rotate relative to the base, and causing the first main swing arm to rotate relative to the first fixed frame, and causing the first door plate to rotate relative to the first fixed frame and to rotate and slide relative to the first main swing arm, thereby realizing unfolding or folding of the first rotating assembly relative to the base.

[0008] The second rotating assembly comprises a second fixed frame, a second main swing arm and a second door plate. One end of the second main swing arm is rotationally connected with the base, and the other end is rotationally connected with the second fixed frame. The second door plate is arranged in layers with the second fixed frame and is rotationally connected with the second fixed frame and rotationally and slidingly connected with the second main swing arm. The second fixed frame is fixedly connected with the second shell.

[0009] When the second shell rotates relative to the base, the second fixed frame is driven to rotate relative to the base, thereby driving the second main swing arm and the second door plate to rotate relative to the base, and causing the second main swing arm to rotate relative to the second fixed frame, and causing the second door plate to rotate relative to the second fixed frame and to rotate and slide relative to the second main swing arm, thereby realizing unfolding or folding of the second rotating assembly relative to the base, so as to switch the rotating shaft mechanism between the unfolded state and the folded state.

[0010] The synchronous assembly comprises a first swing arm, a second swing arm and a synchronous gear. The synchronous gear comprises a first gear, a second gear, a third gear and a fourth gear. The first gear, the second gear, the third gear and the fourth gear are sequentially mounted on the base along the width direction of the base and are sequentially engaged.

[0011] The first swing arm and the second swing arm are respectively arranged on opposite sides of the base along the width direction of the base, and the first swing arm is fixedly connected with the first gear, and the second swing arm is fixedly connected with the fourth gear. One end of the first swing arm away from the first gear is slidingly connected with the first fixed frame, and one end of the second swing arm away from the fourth gear is slidingly connected with the second fixed frame.

[0012] When the first rotating assembly rotates relative to the base, the first fixed frame drives the first swing arm to rotate relative to the base, thereby causing the first swing arm to drive the second swing arm to rotate relative to the base through the synchronous gear, so as to drive the second rotating assembly to rotate relative to the base, thereby realizing synchronous rotation of the first rotating assembly and the second rotating assembly, that is, realizing synchronous rotation of the rotating shaft mechanism and the foldable electronic device.

[0013] The first gear comprises a first tooth portion. The second gear comprises a second tooth portion and a third tooth portion, which are sequentially arranged along the circumference of the second gear. The radius of the addendum circle of the second tooth portion is greater than the radius of the addendum circle of the first tooth portion. The first tooth portion is engaged with the second tooth portion, the third tooth portion is engaged with the third gear, the third gear is engaged with the fourth gear. When the first swing arm rotates relative to the base, the first gear is driven to rotate, the first tooth portion of the first gear drives the second tooth portion to rotate, so that the second gear rotates, the third tooth portion of the second gear drives the third gear to rotate, the third gear drives the fourth gear to rotate, and the fourth gear drives the second swing arm to rotate. The rotation directions of the first gear and the third gear are the same, the rotation direction of the second gear is the same as that of the fourth gear, and the rotation direction of the first gear is opposite to that of the second gear.

[0014] The support plate is arranged on the side of the synchronous gear away from the base and is fixedly connected with the base. The support plate covers the synchronous gear in the thickness direction of the base.

[0015] In the embodiments of the present application, the radius of the addendum circle of the second tooth portion of the second gear is greater than the radius of the addendum circle of the first tooth portion of the first gear, so that the angle of rotation of the second gear during the rotation of the rotating shaft mechanism can be reduced, that is, the rotation angle of the second tooth portion can be reduced, so that the required avoiding space of the second tooth portion during the rotation can be reduced, and the utilization rate of the space around the second tooth portion can be improved to avoid interference between the second tooth portion and the support plate and improve the structural stability of the support plate. Moreover, when the thickness of the rotating shaft mechanism meets the requirements, the thickness of the position on the support plate opposite to the second tooth portion can be increased to improve the strength of the support plate and the supporting effect of the support plate on the display screen, so that the display screen has better display effect.

[0016] Meanwhile, in the present application, the radius of the addendum circle of the second tooth portion of the second gear is greater than the radius of the addendum circle of the first tooth portion of the first gear, so that the angle of rotation of the second tooth portion during the rotation of the rotating shaft mechanism can be reduced, so that the support plate can be arranged to cover the synchronous gear in the thickness direction of the base, and a hollow portion does not need to be arranged on the support plate at the position corresponding to the second tooth portion to avoid the second tooth portion, so that the structural strength of the support plate can be further improved, and the second tooth portion can also avoid pressing the display screen to cause extrusion to the display screen, so that the flatness of the display screen and the display effect of the display screen can be further improved, and the service life of the display screen can be improved.

[0017] In a possible implementation, the surface of the support plate away from the synchronous gear is provided with an avoiding groove, and the orthogonal projection of the avoiding groove in the thickness direction of the base at least partially coincides with the second gear.

[0018] The display screen is mounted on the rotating shaft mechanism near one side of the support plate, and the display screen is at least partially arranged opposite to the support plate. When the rotating shaft mechanism is in the folded state, the display screen is bent towards the direction of the avoiding groove. The avoiding groove plays an avoiding role for the display screen, so that the display screen can be prevented from being squeezed by the support plate, and the display effect of the display screen can be improved, and the service life of the display screen can be improved.

[0019] In the embodiment, the radius of the addendum circle of the second tooth part of the second gear is greater than the radius of the addendum circle of the first tooth part of the first gear, so as to improve the utilization rate of the space around the second tooth part, and the thickness of the area of the support plate provided with the avoiding groove can be increased, so that the structural strength of the support plate can be further increased.

[0020] In a possible implementation, at least one meshing tooth of the second tooth part towards the support plate is a half tooth. When the rotating shaft mechanism is in the unfolded state, the second tooth part faces the support plate. In the embodiment, the meshing tooth of the second tooth part near the support plate is set as a half tooth, so that interference between the second tooth part and the support plate can be avoided, and the stability of the support plate and the smoothness and stability of the synchronous gear rotation can be improved.

[0021] In a possible implementation, the pitch circle diameter of the second tooth part is different from the pitch circle diameter of the third tooth part. In an implementation, the pitch circle diameter of the third tooth part is smaller than the pitch circle diameter of the third tooth part. That is, the distance from the axis of the second gear to the third tooth part is smaller than the distance from the axis of the second gear to the second tooth part. In this way, the size of the second gear can be reduced, so that the center distance between the second gear and the third gear can be reduced, and the width of the synchronous gear in the width direction of the base can be reduced, so that the width of the rotating shaft mechanism can be reduced, that is, the thickness of the rotating shaft mechanism in the folded state can be reduced. Moreover, by reducing the pitch circle diameter of the third tooth part, the size of the second gear can be reduced, so that the width of the synchronous gear can be reduced, more space can be provided for the support plate and the shaft cover, so that the thickness of the support plate or the shaft cover can be designed to be larger, and the strength of the support plate and the shaft cover can be improved, so that the strength of the rotating shaft mechanism and the foldable electronic device can be improved.

[0022] In other embodiments, the pitch circle diameter of the second tooth part can also be smaller than or equal to the pitch circle diameter of the third tooth part.

[0023] In the embodiment, by adjusting the pitch circle diameter of the second tooth part and the pitch circle diameter of the third tooth part, the position of the axis of the second gear can be adjusted, so that the size of the second gear can be adjusted, the distance between the second gear and the third gear can be adjusted, and the width of the synchronous gear can be adjusted, so that the overall design of the synchronous gear has greater flexibility, and the actual space requirement can be adjusted.

[0024] In a possible implementation, the first gear further comprises a fourth tooth portion coaxially arranged with the first tooth portion and fixedly connected. The meshing teeth of the fourth tooth portion are at least partially misaligned with the meshing teeth of the first tooth portion along the axial direction of the first gear. The second gear further comprises a fifth tooth portion coaxially arranged with the second tooth portion and fixedly connected. The meshing teeth of the fifth tooth portion are at least partially misaligned with the meshing teeth of the second tooth portion along the axial direction of the second gear. The fifth tooth portion meshes with the fourth tooth portion.

[0025] In this embodiment, the first tooth portion and the fourth tooth portion of the first gear are misaligned, and the second tooth portion and the fifth tooth portion of the second gear are misaligned, so that the coincidence degree of the first gear and the second gear is increased, the transmission stability between the first gear and the second gear is improved, and the transmission stability of the rotating shaft mechanism is further improved.

[0026] In a possible implementation, the phase difference between the first tooth portion and the fourth tooth portion is greater than 0 and less than or equal to 1, and the phase difference between the second tooth portion and the fifth tooth portion is greater than 0 and less than or equal to 1.

[0027] When the first gear rotates relative to the second gear, the fourth tooth portion meshes with the fifth tooth portion at the same time when the first tooth portion meshes with the second tooth portion. That is, when the first tooth portion and the second tooth portion are meshing and have not disengaged from the second tooth portion, the fourth tooth portion meshes with the fifth tooth portion; when the fourth tooth portion and the fifth tooth portion are meshing and have not disengaged from the fifth tooth portion, the first tooth portion again meshes with the second tooth portion, so that the first tooth portion and the second tooth portion, and the fourth tooth portion and the fifth tooth portion are all meshing during the process in which the first gear drives the second gear to rotate, so that the coincidence degree of the synchronous gear is improved, and the transmission stability between the first gear and the second gear is improved. In this embodiment, the coincidence degree between the first gear and the second gear is greater than 1. For example, the coincidence degree between the first gear and the second gear is 1.2.

[0028] In a possible implementation, the fourth gear comprises a sixth tooth portion, the third gear comprises a seventh tooth portion and an eighth tooth portion, and the seventh tooth portion and the eighth tooth portion are sequentially arranged along the circumferential direction of the third gear. The radius of the addendum circle of the eighth tooth portion is greater than the radius of the addendum circle of the sixth tooth portion. The eighth tooth portion meshes with the sixth tooth portion, and the seventh tooth portion meshes with the third tooth portion.

[0029] When the first gear drives the second gear to rotate, the third tooth portion of the second gear drives the seventh tooth portion to rotate, thereby driving the third gear to rotate. The eighth tooth portion of the third gear drives the sixth tooth portion to rotate, thereby driving the fourth gear to rotate.

[0030] In the embodiment, the radius of the addendum circle of the eighth tooth portion is greater than the radius of the addendum circle of the sixth tooth portion, so that the angle of rotation of the eighth tooth portion, i.e. the angle of rotation of the third gear, can be reduced, thereby reducing the required clearance space of the third gear during rotation, and further improving the utilization of the space around the third gear. In this way, interference between the third gear and the support plate can be avoided, the structural stability of the support plate is improved, and the thickness of the position of the support plate opposite to the third gear can be increased, and at the same time, the hollow part corresponding to the third gear on the support plate is not required, and the structural strength of the support plate can be further improved.

[0031] In a possible implementation, the pitch circle diameter of the seventh tooth portion is different from the pitch circle diameter of the eighth tooth portion. In an implementation, the pitch circle diameter of the seventh tooth portion is smaller than the pitch circle diameter of the eighth tooth portion. That is, the distance from the axis of the third gear to the seventh tooth portion is smaller than the distance from the axis of the third gear to the eighth tooth portion. In this way, the size of the third gear can be reduced, thereby further reducing the center distance between the third gear and the second gear, and reducing the width of the synchronous gear in the width direction of the base, and further reducing the width of the rotating shaft mechanism, i.e. reducing the thickness of the rotating shaft mechanism in the folded state. Moreover, by reducing the pitch circle diameter of the seventh tooth portion, the size of the third gear can be reduced, thereby reducing the width of the synchronous gear, providing more space for the support plate and the shaft cover, so that the thickness of the support plate or the shaft cover can be designed to be larger, and further improving the strength of the support plate and the shaft cover, thereby improving the strength of the rotating shaft mechanism and the foldable electronic device.

[0032] In other embodiments, the pitch circle diameter of the seventh tooth portion can also be greater than or equal to the pitch circle diameter of the eighth tooth portion.

[0033] In the embodiment, by adjusting the pitch circle diameter of the eighth tooth portion and the pitch circle diameter of the seventh tooth portion, the position of the axis of the third gear can be adjusted, thereby adjusting the distance between the second gear and the third gear, and further adjusting the width of the synchronous gear, so that the overall design of the synchronous gear has greater flexibility, and can be adjusted according to the actual space requirement.

[0034] In an implementation, the size of the base in the width direction is 7.0mm-8.6mm. That is, the thickness of the rotating shaft mechanism in the folded state is 7.0mm-8.6mm.

[0035] In a possible implementation, the synchronous gear includes a plurality of gear sets, and the plurality of gear sets are sequentially arranged along the length direction of the base. Each gear set includes four gears sequentially engaged along the width direction of the base, and the orthographic projections of the meshing teeth of at least two gear sets along the length direction of the base are arranged in a staggered manner.

[0036] In the embodiment, by arranging multiple gear sets and staggering at least two gear sets, the coincidence degree between the two adjacent gears can be increased, thereby improving the transmission stability between the synchronous gears, and further improving the transmission stability of the rotating shaft mechanism.

[0037] In a possible implementation, the first door plate is arranged in a stacked manner with the first fixed frame, and the first door plate is rotationally connected with the first fixed frame and rotationally and slidingly connected with the first swing arm and the first main swing arm. The second door plate is arranged in a stacked manner with the second fixed frame, and the second door plate is rotationally connected with the second fixed frame and rotationally and slidingly connected with the second swing arm and the second main swing arm.

[0038] When the rotating shaft mechanism is in the unfolded state, the first door plate and the second door plate are located on opposite sides of the base in the width direction, and the top surface of the first door plate, the top surface of the second door plate, and the top surface of the support plate are flush. The display screen is mounted on the same side of the first door plate, the second door plate, and the support plate. The first door plate, the second door plate, and the support plate jointly support the display screen, thereby improving the flatness of the display screen and enabling the display screen to have better display effect.

[0039] When the rotating shaft mechanism is rotated from the unfolded state to the folded state, the first fixed frame and the second fixed frame are rotated toward each other, driving the first door plate and the second door plate to rotate toward each other, thereby driving the display screen to bend.

[0040] When the rotating shaft mechanism is in the folded state, the first door plate and the second door plate are arranged oppositely, and the distance between the first door plate and the second door plate gradually increases in the direction of approaching the support plate, thereby forming a water-drop-shaped accommodating space between the first door plate, the second door plate, and the support plate. The bendable part of the display screen is located in the accommodating space, and the bendable part is bent toward the avoiding groove of the support plate. In this way, the display screen can be prevented from being squeezed when the rotating shaft mechanism is in the folded state, the service life of the display screen is improved, and the display screen can be prevented from having creases, thereby improving the user experience.

[0041] In a second aspect, the application provides a foldable electronic device. The foldable electronic device includes a first housing, a second housing, a display screen, and the rotating shaft mechanism described above. The rotating shaft mechanism is connected between the first housing and the second housing, and the first swing arm is connected with the first housing, and the second swing arm is connected with the second housing. The display screen is mounted on the first housing, the second housing, and the rotating shaft mechanism, and at least part of the display screen is arranged oppositely with the support plate.

[0042] In summary, in the embodiments of the present application, by setting the radius of the addendum circle of the second tooth part of the second gear to be greater than the radius of the addendum circle of the first tooth part of the first gear, the angle of rotation of the second gear during rotation of the rotating shaft mechanism can be reduced, that is, the rotation angle of the second tooth part can be reduced, so that the required clearance space of the second tooth part during rotation can be reduced, and the utilization rate of the space around the second tooth part can be improved to avoid interference between the second tooth part and the support plate, and the structural stability of the support plate can be improved. Moreover, when the thickness of the rotating shaft mechanism meets the requirements, the thickness of the position on the support plate opposite to the second tooth part can be increased to improve the strength of the support plate and the supporting effect of the support plate on the display screen, so that the display screen has better display effect.

[0043] Meanwhile, in the present application, by setting the radius of the addendum circle of the second tooth part of the second gear to be greater than the radius of the addendum circle of the first tooth part of the first gear, the angle of rotation of the second tooth part during rotation of the rotating shaft mechanism can be reduced, that is, the rotation angle of the second tooth part can be reduced, so that the required clearance space of the second tooth part during rotation can be reduced, and the utilization rate of the space around the second tooth part can be improved to avoid interference between the second tooth part and the support plate, and the structural stability of the support plate can be improved. Moreover, when the thickness of the rotating shaft mechanism meets the requirements, the thickness of the position on the support plate opposite to the second tooth part can be increased to improve the strength of the support plate and the supporting effect of the support plate on the display screen, so that the display screen has better display effect. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background art, the drawings required to be used in the embodiments of the present application or the background art will be described below.

[0045] FIG. 1 is a structural schematic diagram of a foldable electronic device in a first state according to an embodiment of the present application;

[0046] FIG. 2 is a structural schematic diagram of a foldable electronic device in a second state according to an embodiment of the present application;

[0047] FIG. 3 is a structural schematic diagram of a foldable electronic device in a third state according to an embodiment of the present application;

[0048] FIG. 4 is an exploded structural schematic diagram of the foldable electronic device shown in FIG. 3;

[0049] FIG. 5 is a structural schematic diagram of a rotating shaft mechanism in the foldable electronic device shown in FIG. 4;

[0050] FIG. 6 is an exploded structural schematic diagram of the rotating shaft mechanism shown in FIG. 5;

[0051] FIG. 7 is a structural schematic diagram of a base in the rotating shaft mechanism shown in FIG. 6;

[0052] Fig. 8 is a structural schematic diagram of the first fixed frame and the second fixed frame in the rotating shaft mechanism shown in Fig. 6;

[0053] Fig. 9 is a structural schematic diagram of the first main swing arm and the second main swing arm in the rotating shaft mechanism shown in Fig. 6;

[0054] Fig. 10 is a partial structural schematic diagram of the rotating structure shown in Fig. 5;

[0055] Fig. 11 is a sectional structural schematic diagram of the rotating shaft mechanism shown in Fig. 5;

[0056] Fig. 12 is a sectional structural schematic diagram of the rotating shaft mechanism shown in Fig. 11 in a folded state;

[0057] Fig. 13 is a partial exploded structural schematic diagram of a synchronization assembly in the rotating shaft mechanism shown in Fig. 6;

[0058] Fig. 14 is a partial exploded structural schematic diagram of the synchronization assembly shown in Fig. 13;

[0059] Fig. 15 is a partial exploded structural schematic diagram of the synchronization assembly shown in Fig. 13;

[0060] Fig. 16 is a partial structural schematic diagram of the rotating shaft mechanism shown in Fig. 13;

[0061] Fig. 17 is a partial structural schematic diagram of a rotating shaft mechanism provided by another embodiment of the present application;

[0062] Fig. 18 is a partial structural schematic diagram of a synchronization gear shown in Fig. 16;

[0063] Fig. 19 is a partial structural schematic diagram of the synchronization gear shown in Fig. 16;

[0064] Fig. 20 is a partial exploded structural schematic diagram of the synchronization assembly shown in Fig. 13;

[0065] Fig. 21 is a structural schematic diagram of the first swing arm and the second swing arm in the synchronization assembly shown in Fig. 13;

[0066] Fig. 22 is a partial structural schematic diagram of the rotating shaft mechanism shown in Fig. 5;

[0067] Fig. 23 is a sectional structural schematic diagram of the rotating shaft mechanism shown in Fig. 5;

[0068] Fig. 24 is another sectional structural schematic diagram of the rotating shaft mechanism shown in Fig. 5;

[0069] Fig. 25 is a sectional structural schematic diagram of the rotating shaft mechanism shown in Fig. 24 in a folded state;

[0070] Fig. 26 is a structural schematic diagram of a support plate in the rotating shaft mechanism shown in Fig. 5;

[0071] Fig. 27 is a partial structural schematic diagram of the rotating shaft mechanism shown in Fig. 5;

[0072] FIG. 28 is a partially exploded structural schematic diagram of the hinge mechanism shown in FIG. 5;

[0073] FIG. 29 is a partially structural schematic diagram of the first door plate and the second door plate in the hinge mechanism shown in FIG. 28;

[0074] FIG. 30 is a cross-sectional structural schematic diagram of the hinge mechanism shown in FIG. 5;

[0075] FIG. 31 is a structural schematic diagram of the hinge mechanism shown in FIG. 30 in a folded state. DETAILED DESCRIPTION

[0076] The embodiments of the present application will be described below with reference to the accompanying drawings.

[0077] Please refer to FIG. 1 to FIG. 3, FIG. 1 is a structural schematic diagram of a foldable electronic device 500 in a first state according to an embodiment of the present application, FIG. 2 is a structural schematic diagram of the foldable electronic device 500 in a second state according to an embodiment of the present application, and FIG. 3 is a structural schematic diagram of the foldable electronic device 500 in a third state according to an embodiment of the present application.

[0078] For the convenience of description, the width direction of the foldable electronic device 500 is defined as the X direction, the length direction of the foldable electronic device 500 is defined as the Y direction, and the thickness direction of the foldable electronic device 500 is defined as the Z direction. The X direction, the Y direction and the Z direction are perpendicular to each other.

[0079] The foldable electronic device 500 includes, but is not limited to, a cellphone, a notebook computer, a tablet personal computer, a laptop computer, a personal digital assistant, a wearable device, or a mobile device, etc. In the embodiments of the present application, the foldable electronic device 500 is taken as an example of a cellphone.

[0080] The foldable electronic device 500 shown in FIG. 1 is in a folded state, the foldable electronic device 500 shown in FIG. 2 is in a half unfolded state, and the foldable electronic device 500 shown in FIG. 3 is in an unfolded state. The unfolding angle a of the foldable electronic device 500 shown in FIG. 2 is 90 degrees, and the unfolding angle β of the foldable electronic device 500 shown in FIG. 3 is 180 degrees.

[0081] It should be noted that the angles illustrated in the embodiments of the present application are allowed to have a little deviation. For example, the unfolded angle a of the foldable electronic device 500 shown in FIG. 2 is 90 degrees, which means that a can be 90 degrees, or approximately 90 degrees, such as 80 degrees, 85 degrees, 95 degrees or 0 degrees, etc. The unfolded angle β of the foldable electronic device 500 shown in FIG. 3 is 180 degrees, which means that β can be 180 degrees, or approximately 180 degrees, such as 170 degrees, 175 degrees, 185 degrees and 190 degrees, etc. The angles illustrated in the following embodiments can be understood in the same way.

[0082] The foldable electronic device 500 illustrated in the embodiments of the present application is an electronic device that can be folded once. In some other embodiments, the foldable electronic device 500 can also be an electronic device that can be folded multiple times (more than twice). At this time, the foldable electronic device 500 can include multiple parts, and adjacent two parts can be relatively close to be folded to the foldable electronic device 500 in a folded state, and adjacent two parts can be relatively far away to be unfolded to the foldable electronic device 500 in an unfolded state.

[0083] Referring to FIG. 4, FIG. 4 is an exploded structural schematic diagram of the foldable electronic device 500 shown in FIG. 3.

[0084] The foldable electronic device 500 comprises the folding device 200 and the display screen 300, and the display screen 300 is installed on the folding device 200. The display screen 300 comprises a display surface 310 and a mounting surface 320, and the display surface 310 and the mounting surface 320 are oppositely arranged. The display surface 310 is used for displaying text, images, videos and the like. The display screen 300 comprises a first part 330, a second part 340 and a bendable part 350. The bendable part 350 is located between the first part 330 and the second part 340, and the bendable part 350 can bend around a direction with the Y direction as an axis. The first part 330, the second part 340 and the bendable part 350 jointly constitute the display screen 300. In the embodiment, the display screen 300 adopts a flexible display screen, for example, an organic light-emitting diode (OLED) display screen, an active-matrix organic light-emitting diode (AMOLED) display screen, a mini organic light-emitting diode display screen, a micro organic light-emitting diode display screen, a micro organic light-emitting diode display screen or a quantum dot light emitting diode (QLED) display screen.

[0085] The folding device 200 comprises a first housing 210, a second housing 220 and a hinge mechanism 100. The hinge mechanism 100 is located between the first housing 210 and the second housing 220, and is fixedly connected with the first housing 210 and the second housing 220, so as to realize the rotational connection between the first housing 210 and the second housing 220. The display screen 300 is installed on the folding device 200, and the mounting surface 320 is fixedly connected with the folding device 200. Specifically, the first housing 210 bears the first part 330 of the display screen 300, and the second housing 220 bears the second part 340. In other words, the first part 330 is installed on the first housing 210, and the second part 340 is installed on the second housing 220. The hinge mechanism 100 is oppositely arranged with the bendable part 350. The first housing 210 and the second housing 220 can be relatively rotated through the hinge mechanism 100, so that the folding device 200 is switched between the folded state and the unfolded state.

[0086] In combination with FIG. 1, the first shell 210 and the second shell 220 rotate towards each other by the rotating shaft mechanism 100 to drive the display screen 300 to bend, so that the foldable electronic device 500 is folded. When the foldable electronic device 500 is in the folded state, the bendable part 350 of the display screen 300 is bent, and the first part 330 and the second part 340 are oppositely arranged. At this time, the display screen 300 is located between the first shell 210 and the second shell 220, which can greatly reduce the probability of damage to the display screen 300 and effectively protect the display screen 300.

[0087] In combination with FIG. 2 and FIG. 4, the first shell 210 and the second shell 220 rotate away from each other by the rotating shaft mechanism 100 to drive the display screen 300 to unfold, so that the foldable electronic device 500 is unfolded to a half-unfolded state. When the foldable electronic device 500 is in the half-unfolded state, the included angle between the first shell 210 and the second shell 220 is α, the first part 330 and the second part 340 are oppositely unfolded, and the bendable part 350 is unfolded. At this time, the included angle between the first part 330 and the second part 340 is α. In this embodiment, α is 90 degrees. In other embodiments, α can also be about 90 degrees, and can also be 80 degrees, 85 degrees, 95 degrees or 0 degrees, etc.

[0088] In combination with FIG. 3 and FIG. 4, the first shell 210 and the second shell 220 continue to rotate away from each other by the rotating shaft mechanism 100 to drive the display screen 300 to further unfold, until the foldable electronic device 500 is unfolded to an unfolded state. When the foldable electronic device 500 is in the unfolded state, the included angle between the first shell 210 and the second shell 220 is β. The bendable part 350 is unfolded, and the first part 330 and the second part 340 are oppositely unfolded. At this time, the included angle between the first part 330, the second part 340 and the bendable part 350 is β, and the display screen 300 has a large display area, realizing large-screen display of the foldable electronic device 500 and improving the user experience. In this embodiment, β is 180 degrees. In other embodiments, β can also be about 180 degrees, and can also be 170 degrees, 175 degrees, 185 degrees and 190 degrees, etc.

[0089] It should be noted that the included angle α and the included angle β are the included angles between the first shell 210 and the second shell 220, which are only used to distinguish the angles between the first shell 210 and the second shell 220 in different states of the foldable electronic device 500. Among them, the included angle α refers to the angle between the first shell 210 and the second shell 220 when the foldable electronic device 500 is in the half-unfolded state; the included angle β refers to the angle between the first shell 210 and the second shell 220 when the foldable electronic device 500 is in the unfolded state.

[0090] Please refer to FIG. 5 and FIG. 6, FIG. 5 is a structural schematic diagram of the hinge mechanism 100 in the foldable electronic device 500 shown in FIG. 4, and FIG. 6 is an exploded structural schematic diagram of the hinge mechanism 100 shown in FIG. 5.

[0091] The hinge mechanism 100 comprises a base 10, a first rotating assembly 101, a second rotating assembly 102, a synchronous assembly 1 and a support plate 70. The first rotating assembly 101 and the second rotating assembly 102 are respectively located on opposite sides of the base 10 in the width direction and are rotationally connected with the base 10. The first rotating assembly 101 comprises a first fixed frame 21, a first main swing arm 31 and a first door plate 81. One end of the first main swing arm 31 is rotationally connected with the base 10, and the other end is rotationally connected with the first fixed frame 21. The first door plate 81 is stacked with the first fixed frame 21 and is rotationally connected with the first fixed frame 21 and rotationally and slidingly connected with the first main swing arm 31.

[0092] The first fixed frame 21 is fixedly connected with a first housing 210. When the first housing 210 rotates relative to the base 10, the first fixed frame 21 is driven to rotate relative to the base 10, thereby driving the first main swing arm 31 and the first door plate 81 to rotate relative to the base 10, and driving the first main swing arm 31 to rotate relative to the first fixed frame 21, and driving the first door plate 81 to rotate relative to the first fixed frame 21 and to rotate and slide relative to the first main swing arm 31, thereby realizing the unfolding or folding of the first rotating assembly 101 relative to the base 10.

[0093] The second rotating assembly 102 comprises a second fixed frame 22, a second main swing arm 32 and a second door plate 82. One end of the second main swing arm 32 is rotationally connected with the base 10, and the other end is rotationally connected with the second fixed frame 22. The second door plate 82 is stacked with the second fixed frame 22 and is rotationally connected with the second fixed frame 22 and rotationally and slidingly connected with the second main swing arm 32.

[0094] The second fixed frame 22 is fixedly connected with a second housing 220. When the second housing 220 rotates relative to the base 10, the second fixed frame 22 is driven to rotate relative to the base 10, thereby driving the second main swing arm 32 and the second door plate 82 to rotate relative to the base 10, and driving the second main swing arm 32 to rotate relative to the second fixed frame 22, and driving the second door plate 82 to rotate relative to the second fixed frame 22 and to rotate and slide relative to the second main swing arm 32, thereby realizing the unfolding or folding of the second rotating assembly 102 relative to the base 10, so as to realize the switching of the hinge mechanism 100 between the unfolded state and the folded state.

[0095] The synchronous assembly 1 comprises a first swing arm 61, a second swing arm 62, a synchronous gear 40 and a damping member 50. The synchronous gear 40 and the damping member 50 are both mounted on the base 10. The first swing arm 61 and the second swing arm 62 are respectively connected to opposite sides of the synchronous gear 40 in the width direction and are hingedly connected to the damping member 50. The first swing arm 61 is arranged in the length direction (Y direction) of the base 10 apart from the first main swing arm 31, and the first swing arm 61 is slidingly connected to the first fixed frame 21 and is rotatably and slidingly connected to the first door plate 81. The second swing arm 62 is arranged in the length direction of the base 10 apart from the second main swing arm 32, and the second swing arm 62 is slidingly connected to the second fixed frame 22 and is rotatably and slidingly connected to the second door plate 82.

[0096] When the first rotating assembly 101 rotates relative to the base 10, the first swing arm 61 is driven to rotate relative to the base 10, so that the first swing arm 61 drives the second swing arm 62 to rotate relative to the base 10 through the synchronous gear 40, so as to drive the second rotating assembly 102 to rotate relative to the base 10, thereby realizing the synchronous rotation of the first rotating assembly 101 and the second rotating assembly 102, that is, realizing the synchronous rotation of the first housing 210 and the second housing 220 of the foldable electronic device 500. At the same time, when the first swing arm 61 and the second swing arm 62 rotate relative to the base 10, the damping member 50 is repeatedly pressed, so that the damping member 50 generates an elastic force, which is in turn applied to the first swing arm 61 and the second swing arm 62, thereby providing a damping force for the rotation of the first swing arm 61 and the second swing arm 62, and further providing a damping force for the rotation of the rotating shaft mechanism 100 and providing a damping feeling for the user.

[0097] The support plate 70 is mounted on the top surface of the base 10 and covers the synchronous gear 40. The display screen 300 is mounted on one side of the rotating shaft mechanism 100 in the thickness direction, and the bendable part 350 is arranged opposite to the first door plate 81, the second door plate 82 and the support plate 70. When the first rotating assembly 101 and the second rotating assembly 102 rotate relative to the base 10, the bendable part 350 of the display screen 300 is driven to flatten or bend, so as to switch the foldable electronic device 500 between the unfolded state and the folded state.

[0098] It should be noted that the rotating shaft mechanism 100 comprises a plurality of rotating structures. The plurality of rotating structures are arranged in the Y direction apart from each other on the base 10. In this embodiment, each rotating structure comprises a first fixed frame 21, a second fixed frame 22, a first main swing arm 31, a second main swing arm 32 and a synchronous assembly 1.

[0099] In this embodiment, there are three rotating structures. The three rotating structures are respectively a first rotating structure, a second rotating structure, and a third rotating structure. The first rotating structure, the second rotating structure, and the third rotating structure are arranged in sequence along the Y direction. Among them, the first rotating structure is located on the positive direction side of the Y axis of the base 10, and the third rotating structure is located on the negative direction side of the Y axis of the base 10. The second rotating structure is located between the first rotating structure and the second rotating structure to enhance the stability of the entire rotating shaft mechanism 100. In other embodiments, the rotating structure can also be one, two, or more than four. The number of the above rotating structures can be adjusted according to actual conditions, and the number of the rotating structures is not specifically limited here.

[0100] In this embodiment, the first fixed frame 21, the second fixed frame 22, the first main swing arm 31, the second main swing arm 32, and the synchronization assembly 1 in the first rotating structure and the third rotating structure are all one. The first fixed frame 21, the second fixed frame 22, and the synchronization assembly 1 in the second rotating structure are all one, and the first main swing arm 31 and the second main swing arm 32 are both two. In other embodiments, each group of rotating structures can also include multiple first main swing arms 31, or / and multiple second main swing arms 32, or / and multiple synchronization assemblies 1. Alternatively, under the premise that the entire rotating shaft mechanism 100 includes at least one synchronization assembly 1, some rotating structures in multiple rotating structures can not include a synchronization assembly 1.

[0101] Among them, the first fixed frame 21 of the multiple groups of rotating structures can be a split structure, that is, a separate structural member, and is not fixed to each other. Alternatively, the first fixed frame 21 of the multiple groups of rotating structures can be connected to each other, or partially connected. The second fixed frame 22 of the multiple groups of rotating structures can be a split structure, or can be connected or partially connected to each other.

[0102] As shown in FIG. 6, the rotating shaft mechanism 100 further includes a damping assembly 90. The damping assembly 90 includes an elastic structure 93, a first damping swing arm 91, and a second damping swing arm 92. The elastic structure 93 is installed on the base 10, the first damping swing arm 91 and the second damping swing arm 92 are connected with the elastic structure 93, and are respectively located on opposite sides of the width direction of the base 10. The first damping swing arm 91 is in sliding connection with the first fixed frame 21, and is in rotating and sliding connection with the first door panel 81. The second damping swing arm 92 is in sliding connection with the second fixed frame 22, and is in rotating and sliding connection with the second door panel 82.

[0103] When the rotating shaft mechanism 100 rotates, the first damping swing arm 91 and the second damping swing arm 92 rotate relative to the base 10 and abut against the elastic structure 93, so that the elastic structure 93 generates an elastic force, which in turn acts on the first damping swing arm 91 and the second damping swing arm 92, and then acts on the first rotating assembly 101 and the second rotating assembly 102, thereby providing a damping force for the rotating shaft mechanism 100 and the foldable electronic device 500, and providing a user with a damping feeling.

[0104] In the embodiment, the damping assembly 90 is one. In other embodiments, the damping assembly 90 can also be multiple, and the multiple damping assemblies 90 are arranged along the Y direction.

[0105] Please refer to FIG. 7, which is a structural schematic diagram of the base 10 in the rotating shaft mechanism 100 shown in FIG. 6.

[0106] The base 10 is a long strip structure. The length direction of the base 10 is parallel to the Y direction, the width direction is parallel to the X direction, and the thickness direction is parallel to the Z direction. The base 10 includes a bottom plate 16, a first end plate 17, and a second end plate (not marked in the figure). The bottom plate 16 is a long strip. The first end plate 17 and the second end plate 103 are respectively connected to the opposite sides of the length direction of the bottom plate 16 and enclose the bottom plate 16 to form a receiving space 18. The opening of the receiving space 18 faces the positive direction of the Z axis. The bottom plate 16 is provided with a first rotating groove 11 and a second rotating groove 12. The first rotating groove 11 and the second rotating groove 12 are both arranged along the X direction. The first rotating groove 11 and the second rotating groove 12 are both arc-shaped grooves and are curved towards the bottom surface direction of the base 10. In the embodiment, the first rotating groove 11 and the second rotating groove 12 are oppositely arranged along the X direction and are mirror-symmetric structures. In other embodiments, the first rotating groove 11 and the second rotating groove 12 can also be staggered along the X direction and are center-symmetric structures. It can be understood that the first rotating groove 11 and the second rotating groove 12 are both part of the receiving space 18.

[0107] The base 10 further comprises a first sliding rail 13 and a second sliding rail 14. The first sliding rail 13 is located in the receiving space 18 and connected with the bottom plate 16. The first sliding rail 13 has an arc structure. In the embodiment, there are two first sliding rails 13. The two first sliding rails 13 are respectively arranged on opposite sides of the first sliding rail 13 in the Y direction. Moreover, the axis of the first sliding rail 13 coincides or approximately coincides with the axis of the first rotating groove 11. The first rotating groove 11 and the first sliding rail 13 are both used for mounting the first main swing arm 31, and the first main swing arm 31 can slide along the first rotating groove 11 and the first sliding rail 13. Here, the "sliding of the first main swing arm 31 along the first rotating groove 11 and the first sliding rail 13" can be understood as the rotation of the first main swing arm 31 around the axis of the first rotating groove 11 and the axis of the first sliding rail 13. In the embodiment, by arranging the first sliding rail 13 on both sides of the first rotating groove 11, the stability of the rotation of the first main swing arm 31 relative to the base 10 can be improved.

[0108] In the embodiment, there are two second sliding rails 14. The two first sliding rails 13 are both connected with the bottom plate 16 and respectively arranged on opposite sides of the first sliding rail 13 in the Y direction. The second sliding rail 14 has an arc structure. The axis of the second sliding rail 14 coincides or approximately coincides with the axis of the second rotating groove 12. The second rotating groove 12 and the second sliding rail 14 are both used for mounting the second main swing arm 32, and the second main swing arm 32 can slide along the second rotating groove 12 and the second sliding rail 14. Here, the "sliding of the second main swing arm 32 along the second rotating groove 12 and the second sliding rail 14" can be understood as the rotation of the second main swing arm 32 around the axis of the second rotating groove 12 and the axis of the second sliding rail 14. In the embodiment, by arranging the second sliding rail 14 on both sides of the second rotating groove 12, the stability of the rotation of the second main swing arm 32 relative to the base 10 can be improved.

[0109] The base 10 further comprises a mounting groove 15. The mounting groove 15 is arranged in the Y direction and spaced apart from the first rotating groove 11. The mounting groove 15 can be understood as a part of the receiving space 18. The mounting groove 15 is used for mounting the synchronous gear 40 in the synchronous assembly 1.

[0110] It should be noted that only the structure of the base 10 in the positive direction of the Y axis is shown in FIG. 7, and the structure of the base 10 in the negative direction of the Y axis is the same as or similar to the structure of the base 10 in the positive direction of the Y axis, and the structure of the base 10 in the negative direction of the Y axis can be appropriately adjusted according to the structures of the second rotating structure, the third rotating structure and the damping assembly 90.

[0111] Please refer to FIG. 8, which is a structural schematic diagram of the first fixed frame 21 and the second fixed frame 22 in the rotating shaft mechanism 100 shown in FIG. 6.

[0112] The first fixed frame 21 is in a long strip structure. In the embodiment, the cross section of the first fixed frame 21 along the XZ plane is wedge-shaped, and the thickness of the first fixed frame 21 gradually decreases towards the base 10. The first fixed frame 21 is provided with a first sliding groove 211, a second sliding groove 212 and a third sliding groove 213. The first sliding groove 211 is a linear groove and is arranged along the width direction of the first fixed frame 21. The first sliding groove 211 is used for sliding connection with the first swing arm 61 of the synchronous assembly 1. In the embodiment, the first sliding groove 211 includes two sub-grooves. The two sub-grooves are arranged at intervals along the length direction (Y direction) of the first fixed frame 21. A first avoiding groove 214 is arranged between the two sub-grooves. The first avoiding groove 214 penetrates the first fixed frame 21 along the thickness direction of the first fixed frame 21. The first avoiding groove 214 is used for avoiding the first door plate 81.

[0113] The second sliding groove 212 is arranged at an interval along the Y direction from the first sliding groove 211. The second sliding groove 212 is arranged on the side of the first fixed frame 21 facing the base 10. The second sliding groove 212 is an arc-shaped groove. The second sliding groove 212 is arranged along the thickness direction of the first fixed frame 21. From the two ends of the extension direction of the second sliding groove 212 to the center direction of the second sliding groove 212, the second sliding groove 212 bends towards the positive direction of the X axis, that is, bends towards the direction away from the first fixed frame 21. That is to say, the center of curvature of the second sliding groove 212 is located on the side of the second sliding groove 212 close to the first fixed frame 21. In the embodiment, the second sliding groove 212 is two. The two second sliding grooves 212 are arranged at intervals along the Y direction. In other embodiments, the second sliding groove 212 can also be one, three or more. The second sliding groove 212 is used for connection with the first main swing arm 31, and the first main swing arm 31 can slide along the second sliding groove 212 to realize rotational connection with the first fixed frame 21. It can be understood that the first main swing arm 31 slides along the first sliding groove 211, which can be regarded as the first main swing arm 31 rotating around the center of curvature of the first sliding groove 211.

[0114] The third sliding groove 213 is arranged at an interval along the Y direction from the first sliding groove 211 and the second sliding groove 212. The third sliding groove 213 is an arc-shaped groove. The third sliding groove 213 is arranged along the width direction of the first fixed frame 21. From the two ends of the extension direction of the third sliding groove 213 to the center direction of the third sliding groove 213, the third sliding groove 213 bends towards the negative direction of the Z axis. In the embodiment, the third sliding groove 213 is two. The two third sliding grooves 213 are respectively arranged at opposite ends of the length direction of the first fixed frame 21. In other embodiments, the third sliding groove 213 can also be one, three or more. The third sliding groove 213 is used for connection with the first door plate 81, and the first door plate 81 can slide along the third sliding groove 213 to realize rotational connection with the first fixed frame 21. It can be understood that the first door plate 81 slides along the third sliding groove 213, which can be regarded as the first door plate 81 rotating around the center of curvature of the third sliding groove 213.

[0115] The second fixing frame 22 is mirror-symmetrical with the first fixing frame 21. The second fixing frame 22 is provided with a fourth sliding groove 221, a fifth sliding groove 222 and a sixth sliding groove 223. The fourth sliding groove 221 is arranged along the width direction of the second fixing frame 22. The fourth sliding groove 221 is used for sliding connection with the second swing arm 62 of the synchronous assembly 1. The second avoiding groove 224 is arranged between two sub-slots of the fourth sliding groove 221. The second avoiding groove 224 penetrates the second fixing frame 22 along the thickness direction of the second fixing frame 22. The second avoiding groove 224 is used for avoiding the second door plate 82.

[0116] The fifth sliding groove 222 is arranged along the Y direction and is spaced apart from the fourth sliding groove 221. The fifth sliding groove 222 is arranged on the side of the second fixing frame 22 facing the base 10. The fifth sliding groove 222 is an arc-shaped groove. The fifth sliding groove 222 is arranged along the thickness direction of the second fixing frame 22. From the two ends of the extension direction of the fifth sliding groove 222 to the center direction of the fifth sliding groove 222, the fifth sliding groove 222 is curved towards the positive direction of the X axis, that is, curved towards the direction away from the second fixing frame 22. In the embodiment, the fifth sliding groove 222 is two. The two fifth sliding grooves 222 are arranged along the Y direction and are spaced apart. The fifth sliding groove 222 is used for connecting with the second main swing arm 32, and the second main swing arm 32 can slide along the fifth sliding groove 222 to realize the rotational connection with the second fixing frame 22. It can be understood that the second main swing arm 32 slides along the fourth sliding groove 221, which can be regarded as the rotation of the second main swing arm 32 around the curvature center of the fourth sliding groove 221.

[0117] The sixth sliding groove 223 is arranged along the Y direction and is spaced apart from the fourth sliding groove 221 and the fifth sliding groove 222. The sixth sliding groove 223 is an arc-shaped groove. The sixth sliding groove 223 is arranged along the width direction of the second fixing frame 22. From the two ends of the extension direction of the sixth sliding groove 223 to the center direction of the sixth sliding groove 223, the sixth sliding groove 223 is curved towards the negative direction of the Z axis. In the embodiment, the sixth sliding groove 223 is two. The two sixth sliding grooves 223 are respectively arranged at the opposite ends of the length direction of the second fixing frame 22. The sixth sliding groove 223 is used for connecting with the second door plate 82, and the second door plate 82 can slide along the sixth sliding groove 223 to realize the rotational connection with the second fixing frame 22. It can be understood that the second door plate 82 slides along the sixth sliding groove 223, which can be regarded as the rotation of the second door plate 82 around the curvature center of the sixth sliding groove 223.

[0118] Please refer to FIG. 9, which is a structural schematic diagram of the first main swing arm 31 and the second main swing arm 32 in the rotating shaft mechanism 100 shown in FIG. 6.

[0119] The first main swing arm 31 comprises a first rotating body 311, a first arc-shaped block 312 and a first swing body 313. The first swing body 313 and the first rotating body 311 are sequentially connected along the length direction of the first main swing arm 31. When the rotating shaft mechanism 100 is in the unfolded state, the length direction of the first main swing arm 31 is parallel or substantially parallel to the X direction. The bottom surface of the first rotating body 311 is arc-shaped. The structure of the first rotating body 311 is matched with the structure of the first rotating groove 11. The first rotating body 311 can slide along the first rotating groove 11 to realize the rotating connection between the first main swing arm 31 and the base 10. In the embodiment, the first arc-shaped block 312 is two. The two first arc-shaped blocks 312 are respectively connected to the opposite sides of the first rotating body 311 in the Y direction. The cross sections of the two first arc-shaped blocks 312 are arc-shaped. The two first arc-shaped blocks are respectively arranged in one-to-one correspondence with the two first sliding rails 13 arranged on the base 10. The first arc-shaped block 312 is arranged on the first sliding rail 13, and the first arc-shaped block 312 can slide along the first sliding rail 13 to improve the rotating stability of the first main swing arm 31 relative to the base 10.

[0120] The first main swing arm 31 further comprises a first sliding block 314. The first sliding block 314 is connected to one end of the first swing body 313 away from the first rotating body 311. The first sliding block 314 is arranged along the thickness direction of the first main swing arm 31, that is, along the Z direction. In the embodiment, the cross section of the first sliding block 314 is arc-shaped. The axis of the first sliding block 314 is located on the side of the first sliding block 314 away from the first main swing arm 31. Along the direction from the two ends of the first sliding block 314 to the center of the first sliding block 314, the first sliding block 314 is curved towards the first rotating body 311. In the embodiment, the first sliding block 314 is two. The two first sliding blocks 314 are arranged in the width direction of the first main swing arm 31, that is, in the Y direction. In other embodiments, the first sliding block 314 can also be one or three or more. The first sliding block 314 is arranged in the first fixed frame 21 to realize the rotating connection between the first main swing arm 31 and the first fixed frame 21.

[0121] The first swing body 313 is provided with a first shaft hole 315. The first shaft hole 315 is arranged away from the first sliding block 314 and the first rotating body 311. The axial direction of the first shaft hole 315 is consistent with the width direction of the first main swing arm 31, that is, parallel to the Y direction. The first shaft hole 315 is arranged in the first door panel 81 to realize the rotating and sliding connection.

[0122] The second main swing arm 32 is mirror-symmetrical with the first main swing arm 31. The second main swing arm 32 comprises a second rotating body 321, a second arc-shaped block 322 and a second swing body 323. The second swing body 323 and the second rotating body 321 are sequentially connected along the length direction of the second main swing arm 32. The structure of the second rotating body 321 is adapted to the structure of the second rotating groove 12. The second rotating body 321 can slide along the second rotating groove 12 to realize the rotating connection between the second main swing arm 32 and the base 10. In the embodiment, the second arc-shaped block 322 is two. The two second arc-shaped blocks 322 are respectively connected to the opposite sides of the second rotating body 321 in the Y direction. The cross sections of the two second arc-shaped blocks 322 are both arc-shaped. The two second arc-shaped blocks 322 are respectively arranged in the two second sliding rails 14 of the base 10. The second arc-shaped block 322 is arranged in the second sliding rail 14, and the second arc-shaped block 322 can slide along the second sliding rail 14 to improve the rotating stability of the second main swing arm 32 relative to the base 10.

[0123] The second main swing arm 32 further comprises a second sliding block 324. The second sliding block 324 is connected to one end of the second swing body 323 away from the second rotating body 321. The second sliding block 324 is arranged along the thickness direction of the second main swing arm 32, that is, along the Z direction. In the embodiment, the cross section of the second sliding block 324 is arc-shaped. The axis of the second sliding block 324 is located on the side of the second sliding block 324 away from the second main swing arm 32. Along the direction from the two ends of the second sliding block 324 to the center of the second sliding block 324, the second sliding block 324 is curved towards the second rotating body 321. In the embodiment, the second sliding block 324 is two. The two second sliding blocks 324 are arranged in the width direction of the second main swing arm 32, that is, in the Y direction. In other embodiments, the second sliding block 324 can also be one or three or more. The second sliding block 324 is arranged in the second fixed frame 22 to realize the rotating connection between the second main swing arm 32 and the second fixed frame 22.

[0124] The second swing body 323 is provided with a second shaft hole 325. The second shaft hole 325 is arranged away from the second sliding block 324 and the second rotating body 321. The axis direction of the second shaft hole 325 is consistent with the width direction of the second main swing arm 32, that is, parallel to the Y direction. The second shaft hole 325 is arranged in the second door plate 82 to realize the rotating and sliding connection between the second main swing arm 32 and the second door plate 82.

[0125] Please refer to FIG. 10 and FIG. 11. FIG. 10 is a partial structure diagram of the rotating structure shown in FIG. 5, and FIG. 11 is a cross-sectional structure diagram of the rotating shaft mechanism 100 shown in FIG. 5.

[0126] The first fixed frame 21 and the first main swing arm 31 are arranged on the side of the base 10 in the negative direction of the X axis. The first fixed frame 21 is fixedly connected with the first shell 210. The first rotating body 311 of the first main swing arm 31 is installed in the first rotating groove 11. The first rotating surface faces the bottom wall of the first rotating groove 11, and the first arc-shaped block 312 is installed in the first arc-shaped groove. The back surface (the surface facing the negative direction of the Z axis) of the first arc-shaped block 312 is opposite to and in contact with the groove bottom wall surface of the first arc-shaped groove. The first fixed frame 21 is connected to one end of the first main swing arm 31 away from the base 10. The first sliding block 314 is arranged in the second sliding groove 212.

[0127] When the first shell 210 rotates relative to the base 10, the first fixed frame 21 is driven to rotate relative to the base 10, thereby driving the first main swing arm 31 to rotate relative to the base 10, and driving the first rotating body 311 to slide along the first rotating groove 11 in an arc shape, the first arc-shaped block 312 to slide along the first arc-shaped groove in an arc shape, and the first sliding block 314 to slide along the second sliding groove 212 in an arc shape.

[0128] The second fixed frame 22 and the second main swing arm 32 are arranged on the side of the base 10 in the positive direction of the X axis. The second fixed frame 22 is fixedly connected with the second shell 220. The second rotating body 321 of the second main swing arm 32 is installed in the second rotating groove 12. The second rotating surface faces the bottom wall of the second rotating groove 12, and the second arc-shaped block 322 is installed in the second arc-shaped groove. The back surface (the surface facing the negative direction of the Z axis) of the second arc-shaped block 322 is opposite to and in contact with the groove bottom wall surface of the second arc-shaped groove. The second fixed frame 22 is connected to one end of the second main swing arm 32 away from the base 10. The second sliding block 324 is arranged in the second sliding groove 212.

[0129] When the second shell 220 rotates relative to the base 10, the second fixed frame 22 is driven to rotate relative to the base 10, thereby driving the second main swing arm 32 to rotate relative to the base 10, and driving the second rotating body 321 to slide along the second rotating groove 12 in an arc shape, the second arc-shaped block 322 to slide along the second arc-shaped groove in an arc shape, and the second sliding block 324 to slide along the fifth sliding groove 222 in an arc shape.

[0130] The rotating directions of the first main swing arm 31 and the second main swing arm 32 are opposite. For example, when the rotating shaft mechanism 100 is switched from the unfolded state to the folded state, the first main swing arm 31 rotates in the clockwise direction, and the second main swing arm 32 rotates in the counterclockwise direction. When the rotating shaft mechanism 100 is switched from the folded state to the unfolded state, the first main swing arm 31 rotates in the counterclockwise direction, and the second main swing arm 32 rotates in the clockwise direction.

[0131] As shown in FIG. 11, when the rotating shaft mechanism 100 is in the unfolded state, the first fixed frame 21 and the second fixed frame 22 are unfolded relative to each other, and the first main swing arm 31 and the second main swing arm 32 are unfolded relative to each other. The included angle between the first fixed frame 21 and the second fixed frame 22 is 180 degrees or substantially 180 degrees, and the included angle between the first main swing arm 31 and the second main swing arm 32 is 180 degrees or substantially 180 degrees.

[0132] Please refer to FIG. 12, which is a sectional structure diagram of the rotating shaft mechanism 100 in the folded state.

[0133] When the rotating shaft mechanism 100 is rotated from the unfolded state to the folded state, the first fixed frame 21 and the second fixed frame 22 are rotated towards the direction of approaching each other. That is, the first fixed frame 21 is rotated in the clockwise direction, and the second fixed frame 22 is rotated in the counterclockwise direction. When the first fixed frame 21 is rotated in the clockwise direction, the first main swing arm 31 is driven to rotate in the clockwise direction, and the first rotating body 311 is slid along the first rotating groove 11 towards the direction of moving away from the first rotating groove 11, the first arc-shaped block 312 is slid along the first arc-shaped groove towards the direction of moving away from the first arc-shaped groove, and at the same time, the first sliding block 314 is slid along the third sliding groove 213 towards the inside of the third sliding groove 213.

[0134] When the second fixed frame 22 is rotated in the counterclockwise direction, the second main swing arm 32 is driven to rotate in the counterclockwise direction, and the second rotating body 321 is slid along the second rotating groove 12 towards the direction of moving away from the second rotating groove 12, the second arc-shaped block 322 is slid along the second arc-shaped groove towards the direction of moving away from the second arc-shaped groove, and at the same time, the second sliding block 324 is slid along the sixth sliding groove 223 towards the inside of the sixth sliding groove 223, thereby making the rotating shaft mechanism 100 in the folded state.

[0135] As shown in FIG. 12, when the rotating shaft mechanism 100 is in the folded state, the first fixed frame 21 and the second fixed frame 22 are folded relative to each other, and the first main swing arm 31 and the second main swing arm 32 are folded relative to each other. Specifically, the first fixed frame 21 and the second fixed frame 22 are arranged relative to each other and parallel to each other along the width direction of the base 10. The first main swing arm 31 and the second main swing arm 32 are arranged relative to each other along the width direction of the base 10, and the first main swing arm 31 and the second main swing arm 32 are parallel or substantially parallel.

[0136] During the process of rotating the rotating shaft mechanism 100 from the folded state to the unfolded state, the first fixed frame 21 and the second fixed frame 22 are rotated towards the direction of moving away from each other. The first fixed frame 21 is rotated in the counterclockwise direction, driving the first main swing arm 31 to rotate in the counterclockwise direction, and making the first rotating body 311 slide towards the inside of the first rotating groove 11, and the second arc-shaped block 322 slide towards the inside of the first arc-shaped groove, and at the same time, the first sliding block 314 is slid along the third sliding groove 213 towards the direction of moving away from the third sliding groove 213.

[0137] The second fixed frame 22 rotates in the clockwise direction, drives the second main swing arm 32 to rotate in the clockwise direction, and makes the second rotating body 321 slide towards the second rotating groove 12, and the second arc-shaped groove slides towards the second arc-shaped groove. At the same time, the second sliding block 324 slides along the sixth sliding groove 223 towards the direction away from the sixth sliding groove 223, so that the rotating shaft mechanism 100 is in the unfolded state.

[0138] Please refer to FIG. 13, which is a partially exploded structural schematic diagram of the synchronous assembly 1 in the rotating shaft mechanism 100 shown in FIG. 6.

[0139] The synchronous assembly 1 includes a first swing arm 61, a second swing arm 62, a synchronous gear 40, and a damping member 50. The first swing arm 61 and the second swing arm 62 are respectively connected to opposite sides of the synchronous gear 40 in the width direction. When the first swing arm 61 rotates, it drives the synchronous gear 40 to rotate, and the synchronous gear 40 drives the second swing arm 62 to rotate, thereby realizing the synchronous rotation of the first swing arm 61 and the second swing arm 62. At the same time, the first swing arm 61 and the second swing arm 62 are also hinged to the damping member 50. When the first swing arm 61 and the second swing arm 62 rotate, they abut against the damping member 50, so that the damping member 50 generates a damping force.

[0140] Please refer to FIG. 14, which is a partially exploded structural schematic diagram of the synchronous assembly 1 shown in FIG. 13.

[0141] The synchronous assembly 1 further includes a first fixed seat 45 and a second fixed seat 46. The first fixed seat 45 is provided with four first mounting holes 451. The four first mounting holes 451 are sequentially and spacedly arranged along the length direction of the first fixed seat 45, and penetrate the first fixed seat 45 along the thickness direction of the first fixed seat 45. The length direction of the first fixed seat 45 is parallel to the width direction of the base 10, that is, parallel to the X direction. The thickness direction of the first fixed seat 45 is parallel to the length direction of the base 10, that is, parallel to the Y direction. It can be understood that the axial direction of the first mounting hole 451 is parallel to the Y direction. The second fixed seat 46 is provided with four second mounting holes 461. The four second mounting holes 461 all penetrate the second fixed seat 46 along the Y direction. The four second mounting holes 461 are sequentially and spacedly arranged along the X direction. The first fixed seat 45 and the second fixed seat 46 are both installed in the mounting groove 15 of the base 10, and are fixedly connected with the base 10. The first fixed seat 45 and the second fixed seat 46 are spacedly arranged along the Y direction, and the four first mounting holes 451 and the four second mounting holes 461 are oppositely arranged one by one.

[0142] The synchronous assembly 1 further comprises rotating rods 47. In the embodiment, there are four rotating rods 47. The four rotating rods 47 are respectively a first rotating rod 471, a second rotating rod 472, a third rotating rod 473 and a fourth rotating rod 474. The first rotating rod 471 comprises a first flat shaft segment 4711. The outer circumferential surface of the first flat shaft segment 4711 comprises a flat surface portion and an arc surface portion (not labeled in the figure). The outer circumferential surface refers to a surface around an axis. It can be understood that the cross section of the first flat shaft segment 4711 perpendicular to the axis has an arc edge and a straight edge. The fourth rotating rod 474 comprises a second flat shaft segment 4741. The outer circumferential surface of the second flat shaft segment 4741 comprises a flat surface portion and an arc surface portion.

[0143] The first rotating rod 471, the second rotating rod 472, the third rotating rod 473 and the fourth rotating rod 474 are parallel to the Y direction in the axial direction, and the first rotating rod 471, the second rotating rod 472, the third rotating rod 473 and the fourth rotating rod 474 are sequentially and spaced apart in the X direction. The four rotating rods 47 are respectively installed in the four first mounting holes 451 and the corresponding second rotating holes 624, and can rotate relative to the first fixed seat 45 and the second fixed seat 46. That is, one rotating rod 47 is installed in the first mounting hole 451 and the corresponding second mounting hole 461. In the embodiment, the length of the first rotating rod 471 and the length of the fourth rotating rod 474 are both greater than the length of the second rotating rod 472 and the length of the third rotating rod 473. The first rotating rod 471 and the fourth rotating rod 474 penetrate through the second fixed seat 46, and the first flat shaft segment 4711 and the second flat shaft segment 4741 extend away from the second fixed seat 46 and are used for mounting the damping member 50. At the same time, the first flat shaft segment 4711 is used for fixedly connecting with the first swing arm 61, and the second flat shaft segment 4741 is used for fixedly connecting with the second swing arm 62.

[0144] The synchronous gear 40 comprises a first gear 41, a second gear 42, a third gear 43 and a fourth gear 44. The synchronous gear 40 is installed on the rotating rod 47 and located between the first fixed seat 45 and the second fixed seat 46. The first gear 41 is sleeved on the outer circumference of the first rotating rod 471 and fixedly connected with the first rotating rod 471. The second gear 42 is sleeved on the outer circumference of the second rotating rod 472 and fixedly connected with the second rotating rod 472. The third gear 43 is sleeved on the outer circumference of the third rotating rod 473 and fixedly connected with the third rotating rod 473. The fourth gear 44 is sleeved on the outer circumference of the fourth rotating rod 474 and fixedly connected with the fourth rotating rod 474.

[0145] The first gear 41, the second gear 42, the third gear 43 and the fourth gear 44 are arranged in sequence along the X direction and are in meshing sequence. That is, the first gear 41 is in meshing with the second gear 42, the second gear 42 is in meshing with the third gear 43, and the third gear 43 is in meshing with the fourth gear 44. When the first rotating rod 471 rotates relative to the base 10, the first gear 41 is driven to rotate, thereby driving the second gear 42 to rotate, the second gear 42 drives the third gear 43 to rotate, the third gear 43 drives the fourth gear 44 to rotate, and the fourth rotating rod 474 is driven to rotate relative to the base 10, thereby realizing the simultaneous rotation of the first gear 41, the second gear 42, the third gear 43 and the fourth gear 44, and realizing the synchronous rotation of the first rotating rod 471 and the fourth rotating rod 474. Among them, the rotation direction of the first gear 41 is the same as that of the third gear 43, the rotation direction of the second gear 42 is the same as that of the fourth gear 44, and the rotation direction of the first gear 41 is opposite to that of the fourth gear 44. The rotation directions of the first rotating rod 471 and the fourth rotating rod 474 are opposite.

[0146] Please refer to FIG. 15 and FIG. 16, FIG. 15 is a partially exploded structural schematic diagram of the synchronous assembly 1 shown in FIG. 13, and FIG. 16 is a partially structural schematic diagram of the rotating shaft mechanism 100 shown in FIG. 13.

[0147] The first gear 41 comprises a plurality of gear segments. In the embodiment, the first gear 41 comprises two gear segments. The two gear segments are respectively a first gear segment 411 and a second gear segment 412. The first gear segment 411 and the second gear segment 412 are arranged in sequence along the axial direction of the first gear 41, that is, in sequence along the Y direction. The first gear segment 411 comprises a first tooth portion 4111. The first tooth portion 4111 comprises a plurality of meshing teeth arranged in sequence along the circumferential direction of the first gear segment 411, and a groove is arranged between every two adjacent meshing teeth. In the embodiment, part of the outer circumferential surface of the first gear segment 411 is provided with meshing teeth, and part of the outer circumferential surface of the first gear segment 411 is not provided with meshing teeth, which is a circular arc surface. In this way, the strength of the first gear 41 can be improved. In other embodiments, the first tooth portion 4111 can also surround one circle of the first gear segment 411. That is, the outer circumferential surface of the first gear segment 411 is provided with the first tooth portion 4111. For example, the first tooth portion 4111 comprises three meshing teeth. Alternatively, the first tooth portion can also comprise two, four or more meshing teeth.

[0148] The second tooth segment 412 comprises a fourth tooth portion 4121. The fourth tooth portion 4121 comprises a plurality of meshing teeth arranged at intervals in the circumferential direction of the second tooth segment 412, and a groove is arranged between every two adjacent meshing teeth. In this embodiment, the outer circumferential surface of part of the second tooth segment 412 is provided with meshing teeth, and the outer circumferential surface of part of the second tooth segment 412 is not provided with meshing teeth, i.e. is a circular arc surface. In this way, the strength of the second gear 42 can be improved. In other embodiments, the fourth tooth portion 4121 can also surround one turn of the second tooth segment 412. That is, the outer circumferential surface of the second tooth segment 412 is provided with the fourth tooth portion 4121. For example, the fourth tooth portion 4121 comprises three meshing teeth. Alternatively, the fourth tooth portion 4121 can also comprise two, four or more meshing teeth.

[0149] The first tooth portion 4111 and the fourth tooth portion 4121 are arranged at intervals. That is, the meshing teeth of the first tooth portion 4111 and the meshing teeth of the fourth tooth portion 4121 are arranged at least partially at intervals in the axial direction of the first gear 41, i.e. in the Y direction. That is, the projection of the meshing teeth of the first tooth portion 4111 in the axial direction of the first gear 41 is at least partially located between the projections of the meshing teeth of two adjacent fourth tooth portions 4121. In this embodiment, the first tooth portion 4111 and the fourth tooth portion 4121 have a phase difference. That is, the projection of the meshing teeth of the first tooth portion 4111 in the Y direction is located between the projections of the meshing teeth of two adjacent fourth tooth portions 4121. It can be understood that, after the first tooth segment 411 is rotated by a phase angle about the axial direction thereof, the projection of the meshing teeth of the first tooth portion 4111 and the projection of the meshing teeth of the fourth tooth portion 4121 coincide or partially coincide in the axial direction of the first gear 41. For example, when the number of teeth of the first tooth portion 4111 and the number of teeth of the fourth tooth portion 4121 are the same, and the size and shape of the meshing teeth are the same, after the first tooth segment 411 is rotated by a phase angle about the axial direction thereof, the projection of the meshing teeth of the first tooth portion 4111 and the projection of the meshing teeth of the fourth tooth portion 4121 coincide completely in the axial direction of the first gear 41. When the first tooth portion 4111 has two meshing teeth and the fourth tooth portion 4121 has three meshing teeth, after the first tooth segment 411 is rotated by a phase angle about the axial direction thereof, the projections of the two meshing teeth of the first tooth portion 4111 and the projections of two meshing teeth of the fourth tooth portion 4121 coincide completely in the axial direction of the first gear 41.

[0150] For example, one phase angle of the first gear 41 is 22.5°. That is, after the first tooth segment 411 is rotated by 22.5° about the axial direction thereof, the projection of the first tooth portion 4111 and the projection of the fourth tooth portion 4121 coincide or partially coincide in the axial direction of the first gear 41.

[0151] It should be noted that the phase angle refers to the angle of a phase, that is, the angle of rotation of a gear when the tooth tip of one gear is in contact with the tooth tip of another gear. For example, the phase angle between the first tooth segment 411 and the second tooth segment 421 refers to the angle of rotation of the first tooth segment 411 when the first tooth of the first tooth segment 411 is in contact with the second gear 42 and the second tooth of the first tooth segment 411 is in contact with the second gear 42.

[0152] In another embodiment, as shown in FIG. 17, the phase difference between the first tooth segment 411 and the fourth tooth segment 412 can also be less than one. For example, the phase difference between the first tooth segment 411 and the fourth tooth segment 412 is half a phase angle. That is, after rotating the first tooth segment 411 around its axis by half a phase angle, the orthographic projection of the tooth of the first tooth segment 411 and the orthographic projection of the tooth of the fourth tooth segment 412 overlap or partially overlap along the axis of the first gear 41. For example, the angle between the tooth of the first tooth segment 411 and the tooth of the fourth tooth segment 412 is 11.25°. That is, after rotating the first tooth segment 411 around its axis by 11.25°, the orthographic projection of the tooth of the first tooth segment 411 and the orthographic projection of the tooth of the fourth tooth segment 412 overlap or partially overlap along the axis of the first gear 41.

[0153] In other embodiments, the phase difference between the first tooth segment 411 and the fourth tooth segment 412 can also be 0.3 times or 0.2 times a phase angle. Here, the phase difference between the first tooth segment 411 and the fourth tooth segment 412 is not specifically limited as long as the phase difference between the first tooth segment 411 and the fourth tooth segment 412 is greater than 0 and less than or equal to 1.

[0154] Please continue to refer to FIG. 15 and FIG. 16, the second gear 42 includes a plurality of tooth segments. In this embodiment, the second gear 42 includes two tooth segments. The two tooth segments are a third tooth segment 421 and a fourth tooth segment 422. The third tooth segment 421 and the fourth tooth segment 422 are sequentially arranged along the Y direction.

[0155] The third tooth segment 421 includes a second tooth segment 4211 and a third tooth segment 4212. The second tooth segment 4211 and the third tooth segment 4212 are spaced apart along the circumference of the third tooth segment 421, and the second tooth segment 4211 is used to engage with the first tooth segment 411, and the third tooth segment 4212 is used to engage with the third gear 43. The second tooth segment 4211 includes a plurality of teeth spaced apart along the circumference of the second gear 42. In this embodiment, the second tooth segment 4211 includes three teeth. In other embodiments, the second tooth segment 4211 can include two or four or more teeth. The third tooth segment 4212 includes a plurality of teeth spaced apart along the circumference of the second gear 42. In this embodiment, the third tooth segment 4212 includes two teeth. In other embodiments, the third tooth segment 4212 can include three or more teeth.

[0156] The fourth tooth segment 422 comprises a fifth tooth portion 4221 and a ninth tooth portion 4222. The fifth tooth portion 4221 and the ninth tooth portion 4222 are spaced apart along the circumference of the fourth tooth segment 422, and the fifth tooth portion 4221 is configured to engage with the fourth tooth portion 4121, and the ninth tooth portion 4222 is configured to engage with the third gear 43. The fifth tooth portion 4221 comprises a plurality of teeth spaced apart along the circumference of the second gear 42. In the embodiment, the fifth tooth portion 4221 comprises three teeth. The ninth tooth portion 4222 comprises a plurality of teeth spaced apart along the circumference of the second gear 42. In the embodiment, the ninth tooth portion 4222 comprises two teeth.

[0157] The second tooth portion 4211 and the fifth tooth portion 4221 are misaligned. Along the axial direction of the second gear 42, the teeth of the second tooth portion 4211 and the teeth of the fifth tooth portion 4221 are at least partially misaligned. That is, the projection of the teeth of the second tooth portion 4211 along the axial direction of the second gear 42 is at least partially located between the projections of the teeth of two adjacent fifth tooth portions 4221. In the embodiment, the second tooth portion 4211 and the fifth tooth portion 4221 have a phase difference. That is, the projection of the teeth of the second tooth portion 4211 along the Y direction is located between the projections of the teeth of two adjacent fifth tooth portions 4221. It can be understood that after the third tooth segment 421 is rotated by a phase angle about the axial direction, the projection of the teeth of the second tooth portion 4211 along the axial direction of the third gear 43 coincides or partially coincides with the projection of the teeth of the fifth tooth portion 4221.

[0158] As shown in FIGS. 13 and 16, the first tooth portion 4111 engages with the second tooth portion 4211, and the fourth tooth portion 4121 engages with the fifth tooth portion 4221. When the first rotating rod 471 rotates relative to the base 10, the first gear 41 is driven to rotate, and the second gear 42 is driven to rotate by the first gear 41. During the process that the first gear 41 drives the second gear 42 to rotate, the fourth tooth portion 4121 engages with the fifth tooth portion 4221 when the first tooth portion 4111 is engaging with the second tooth portion 4211 and has not disengaged from the second tooth portion 4211; and the first tooth portion 4111 engages with the second tooth portion 4211 again when the fourth tooth portion 4121 is engaging with the fifth tooth portion 4221 and has not disengaged from the fifth tooth portion 4221. That is, during the process that the first gear 41 drives the second gear 42 to rotate, the first tooth portion 4111 and the second tooth portion 4211, and the fourth tooth portion 4121 and the fifth tooth portion 4221 are engaged, so as to improve the coincidence degree of the synchronous gear 40 and the transmission stability between the first gear 41 and the second gear 42. In the embodiment, the coincidence degree between the first gear 41 and the second gear 42 is greater than 1. For example, the coincidence degree between the first gear 41 and the second gear 42 is 1.2.

[0159] It should be noted that the coincidence degree of the gear refers to the ratio of the actual meshing line to the normal pitch. The coincidence degree greater than 1 is the condition that the gear can continuously mesh. The coincidence degree represents the ratio of the frequency of the simultaneous meshing of two teeth and the meshing of one tooth in the meshing process. The higher the frequency of the simultaneous meshing of two teeth, the higher the coincidence degree, the better the synchronization performance of the synchronous gear, the smaller the load on a single tooth, the more stable the structure of the meshing tooth of the gear, the gear is less likely to bend, and the noise in the rotation process of the gear is smaller. Moreover, the greater the coincidence degree of the gear, the higher the transmission efficiency and stability of the gear. The calculation formula of the end face coincidence degree of the external gear is:

[0160] wherein z1 and z2 are the number of teeth of the gear, α a1 and α a2 are the addendum circle pressure angles, and α' is the end face division circle meshing angle.

[0161] In this embodiment, by setting the first tooth part 4111 and the fourth tooth part 4121 to be staggered, and setting the second tooth part 4211 and the fifth tooth part 4221 to be staggered, the number of simultaneously meshing gears can be increased, thereby the coincidence degree of the first gear 41 and the second gear 42 can be increased, and the transmission stability between the first gear 41 and the second gear 42 can be improved. At the same time, the load on a single meshing tooth can be reduced, the structure of the meshing tooth of the gear is more stable, the gear is less likely to bend, and the noise in the rotation process of the first gear 41 and the second gear 42 can be reduced. Moreover, when the coincidence degree meets the requirements, the size of the first gear 41 and the second gear 42 can be reduced, thereby the thickness of the rotating shaft mechanism 100 and the foldable electronic device 500 can be reduced, which is beneficial to realize the thinning of the foldable electronic device 500. For example, the radius of the addendum circle of the first gear 41 and the second gear 42 is less than or equal to 2 mm.

[0162] Please refer to FIG. 18, which is a partial structure diagram of the synchronous gear 40 shown in FIG. 16.

[0163] In this embodiment, the radius of the addendum circle of the second tooth part 4211 is greater than the radius of the addendum circle of the first tooth part 4111. The addendum circle refers to the circle where the addendum end is located, and the radius of the addendum circle refers to the distance from the addendum end to the rotation center. As shown in FIG. 16, the radius of the addendum circle of the first tooth part 4111 is R1, and the radius of the addendum circle of the second tooth part 4211 is R2. R2 is greater than R1. It should be noted that when the rotation distance of the gear is the same, the greater the radius of the addendum circle, the smaller the rotation angle of the corresponding tooth part. The rotation distance of the gear refers to the arc length passed by the addendum in the rotation process of the gear.

[0164] It can be understood that the linear speed of the second tooth portion 4211 is the same as the linear speed of the first tooth portion 4111, that is, the distance of rotation of the second tooth portion 4211 is the same as the distance of rotation of the first tooth portion 4111 in the same time. When the first gear 41 and the second gear 42 rotate simultaneously, the angle of rotation of the second tooth portion 4211 is smaller than the angle of rotation of the first tooth portion 4111. That is, the angle of rotation of the second gear 42 is smaller than the angle of rotation of the first gear 41. For example, when the rotation shaft mechanism 100 rotates from the unfolded state to the folded state, the angle of rotation of the first gear 41 is 90 degrees, and the angle of rotation of the second gear 42 is smaller than 90 degrees. In this way, the required avoiding space of the second tooth portion 4211 in the rotation process is smaller than the required avoiding space of the first tooth portion 4111 in the rotation process, so as to improve the utilization rate of the space around the second tooth portion 4211.

[0165] Since the third tooth segment 421 and the fourth tooth segment 422 are coaxially arranged, the angle of rotation of the third tooth segment 421 is the same as the angle of rotation of the fourth tooth segment 422, and the angle of rotation of the third tooth segment 421 and the fourth tooth segment 422 is the angle of rotation of the second gear 42. In the embodiment, the radius of the addendum circle of the first tooth portion 4111 is the same as the radius of the addendum circle of the fourth tooth portion 4121, and the radius of the addendum circle of the second tooth portion 4211 is the same as the radius of the addendum circle of the fifth tooth portion 4221, so as to ensure the smoothness of the transmission of the first gear 41 and the second gear 42. Therefore, the radius of the addendum circle of the fifth tooth portion 4221 is greater than the radius of the addendum circle of the fourth tooth portion 4121. When the first gear 41 and the second gear 42 rotate simultaneously, the angle of rotation of the fifth tooth portion 4221 is smaller than the angle of rotation of the fourth tooth portion 4121, so as to reduce the required avoiding space of the fifth tooth portion 4221 in the rotation process, and further improve the utilization rate of the space around the fifth tooth portion 4221, that is, the utilization rate of the space around the second gear 42.

[0166] Please refer to FIG. 19, which is a schematic diagram of part of the synchronous gear 40 shown in FIG. 16.

[0167] In the embodiment, the pitch circle diameter of the third tooth portion 4212 in the third tooth segment 421 is smaller than the pitch circle diameter of the second tooth portion 4211, and the pitch circle diameter of the ninth tooth portion 4222 in the fourth tooth segment 422 is smaller than the pitch circle diameter of the fifth tooth portion 4221. As shown in FIG. 17, the pitch circle diameter of the second tooth portion 4211 is D1, and the pitch circle diameter of the third tooth portion 4212 is D2. D2 is smaller than D1. That is, the distance from the axis of the second gear 42 to the third tooth portion 4212 is smaller than the distance from the axis of the second gear 42 to the second tooth portion 4211. In this way, the size of the second gear 42 can be reduced, so that the center distance between the second gear 42 and the third gear 43 can be reduced, and the size of the synchronization gear 40 in the X direction and the Z direction can be reduced, and thus the size of the rotating shaft mechanism 100 in the X direction and the Z direction can be reduced, that is, the thickness of the foldable electronic device 500 in the folded state can be reduced. The pitch circle diameter is the reference diameter of the gear, and the pitch circle diameter is positively correlated with the addendum circle radius.

[0168] In other embodiments, the pitch circle diameter of the third tooth portion 4212 can also be greater than or equal to the pitch circle diameter of the second tooth portion 4211. The pitch circle diameter of the ninth tooth portion 4222 can also be greater than or equal to the pitch circle diameter of the fifth tooth portion 4221.

[0169] In the embodiment, by adjusting the pitch circle diameters of the third tooth portion 4212 and the ninth tooth portion 4222, the position of the axis of the second gear 42 can be adjusted, and the size of the second gear 42 can be adjusted, so that the distance between the second gear 42 and the third gear 43 can be adjusted, to adjust the size occupied by the synchronization gear 40 in the X direction and the Z direction, so that the overall design of the synchronization assembly 1 has greater flexibility, and can be adjusted according to actual space requirements. For example, by reducing the pitch circle diameters of the third tooth portion 4212 and the ninth tooth portion 4222, the size of the second gear 42 can be reduced, so that the space occupied by the synchronization gear 40 in the X direction and the Z direction can be reduced, to provide more space for the support plate 70 and the base 10, so that a hollow portion does not need to be provided on the support plate 70 to avoid the second gear 42, and the thickness of the support plate 70 or the shaft cover can also be designed to be larger, and thus the strength of the support plate 70 and the shaft cover can be improved, to improve the strength of the rotating shaft mechanism 100 and the foldable electronic device 500.

[0170] Please continue to refer to FIG. 15 and FIG. 16, the third gear 43 comprises a plurality of tooth segments. In this embodiment, the third gear 43 comprises two tooth segments. The two tooth segments are respectively a fifth tooth segment 431 and a sixth tooth segment 432. The fifth tooth segment 431 and the sixth tooth segment 432 are sequentially arranged along the Y direction. The fifth tooth segment 431 comprises a seventh tooth portion 4311 and an eighth tooth portion 4312. The seventh tooth portion 4311 and the eighth tooth portion 4312 are arranged along the circumference of the fifth tooth segment 431 at intervals, and the seventh tooth portion 4311 is used for meshing with the third tooth portion 4212, and the eighth tooth portion 4312 is used for meshing with the fourth gear 44. Among them, the seventh tooth portion 4311 comprises a plurality of meshing teeth arranged along the circumference of the fifth tooth segment 431 at intervals. The eighth tooth portion 4312 comprises a plurality of meshing teeth arranged along the circumference of the fifth tooth segment 431 at intervals.

[0171] The sixth tooth segment 432 comprises a tenth tooth portion 4321 and an eleventh tooth portion 4322. The tenth tooth portion 4321 and the eleventh tooth portion 4322 are arranged along the circumference of the sixth tooth segment 432 at intervals, and the tenth tooth portion 4321 is used for meshing with the ninth tooth portion 4222, and the eleventh tooth portion 4322 is used for meshing with the fourth gear 44. The tenth tooth portion 4321 comprises a plurality of meshing teeth arranged along the circumference of the sixth tooth segment 432 at intervals. The eleventh tooth portion 4322 comprises a plurality of meshing teeth arranged along the circumference of the sixth tooth segment 432 at intervals.

[0172] As shown in FIG. 13 and FIG. 16, the third gear 43 is arranged on the side of the second gear 42 away from the first gear 41, the seventh tooth portion 4311 meshes with the third tooth portion 4212, and the tenth tooth portion 4321 meshes with the ninth tooth portion 4222. When the first rotating rod 471 rotates relative to the base 10, it drives the first gear 41 to rotate, the first gear 41 drives the second gear 42 to rotate, and the second gear 42 drives the third gear 43 to rotate.

[0173] In this embodiment, the third tooth portion 4212 and the ninth tooth portion 4222 in the second gear 42 are arranged at intervals, and the seventh tooth portion 4311 and the tenth tooth portion 4321 in the third gear 43 are arranged at intervals. The phase difference between the third tooth portion 4212 and the ninth tooth portion 4222 can be one or less than one. The phase difference between the seventh tooth portion 4311 and the tenth tooth portion 4321 can be one or less than one. The phase difference between the third tooth portion 4212 and the ninth tooth portion 4222 can be the same as or different from the phase difference between the first tooth portion 4111 and the fourth tooth portion 4121. The phase difference between the seventh tooth portion 4311 and the tenth tooth portion 4321 can be the same as or different from the phase difference between the second tooth portion 4211 and the fifth tooth portion 4221.

[0174] When the third tooth portion 4212 is engaged with the seventh tooth portion 4311 and not disengaged from the seventh tooth portion 4311, the ninth tooth portion 4222 is engaged with the tenth tooth portion 4321; when the ninth tooth portion 4222 is engaged with the tenth tooth portion 4321 and not disengaged from the tenth tooth portion 4321, the third tooth portion 4212 is engaged with the seventh tooth portion 4311 again. That is, during the rotation of the second gear 42, the third tooth portion 4212 and the seventh tooth portion 4311 are engaged, and the ninth tooth portion 4222 and the tenth tooth portion 4321 are engaged, so that the coincidence degree of the synchronous gear 40 can be improved, and the transmission stability between the second gear 42 and the third gear 43 can be improved. In the embodiment, the coincidence degree between the second gear 42 and the third gear 43 is greater than 1. For example, the coincidence degree between the second gear 42 and the third gear 43 is 1.2.

[0175] In the embodiment, the diameter of the pitch circle of the seventh tooth portion 4311 in the fifth tooth segment 431 is less than the diameter of the pitch circle of the eighth tooth portion 4312, and the diameter of the pitch circle of the tenth tooth portion 4321 in the sixth tooth segment 432 is less than the diameter of the pitch circle of the fifth tooth portion 4221. That is, the distance from the axis of the third gear 43 to the seventh tooth portion 4311 is less than the distance from the axis of the third gear 43 to the eighth tooth portion 4312. In this way, the center distance between the third gear 43 and the second gear 42 can be further reduced, so that the size of the synchronous gear 40 in the X direction can be further reduced, and the size of the rotating shaft mechanism 100 in the X direction can be reduced, that is, the thickness of the foldable electronic device 500 in the folded state can be reduced.

[0176] In other embodiments, the diameter of the pitch circle of the seventh tooth portion 4311 can be greater than or equal to the diameter of the pitch circle of the eighth tooth portion 4312. The diameter of the pitch circle of the tenth tooth portion 4321 can be greater than or equal to the diameter of the pitch circle of the eleventh tooth portion 4322.

[0177] In the embodiment, the position of the axis of the third gear 43 can be adjusted by adjusting the diameters of the pitch circles of the seventh tooth portion 4311 and the tenth tooth portion 4321, that is, the gear of the third gear 43 can be adjusted, so that the size of the synchronous gear 40 in the X direction can be adjusted, and the overall design of the synchronous assembly 1 has greater flexibility, and can be adjusted according to actual space requirements.

[0178] It can be understood that, in the embodiment, the center distance between the two adjacent gears can be adjusted by adjusting the pitch circle diameter of the third tooth portion 4212 and the ninth tooth portion 4222, or by adjusting the pitch circle diameter of the seventh tooth portion 4311 and the tenth tooth portion 4321, or by adjusting the pitch circle diameter of the third tooth portion 4212, the ninth tooth portion 4222, the seventh tooth portion 4311 and the tenth tooth portion 4321 at the same time, so that the size occupied by the synchronous gear 40 in the X direction can be adjusted, and then the size of the base 10 in the width direction can be reduced, which is beneficial to realize the thinning of the rotating shaft mechanism 100 and the foldable electronic equipment 500. For example, in the embodiment, the size of the base 10 in the X direction is 7.0mm-8.6mm, that is, the thickness of the rotating shaft mechanism 100 in the folded state is 7.0mm-8.6mm.

[0179] Meanwhile, in the embodiment, the center distance between the two adjacent gears is adjustable, so that the overall design of the synchronous assembly 1 has greater flexibility, thereby providing more design space for the structure around the synchronous gear 40, such as the support plate 70, the base 10, etc.

[0180] Please continue to refer to FIGS. 15 and 16, the fourth gear 44 includes a plurality of tooth segments. In the embodiment, the fourth gear 44 includes two tooth segments. The two tooth segments are a seventh tooth segment 441 and an eighth tooth segment 442. The seventh tooth segment 441 and the eighth tooth segment 442 are sequentially arranged along the Y direction. The seventh tooth segment 441 includes a sixth tooth portion 4411. The sixth tooth portion 4411 includes a plurality of meshing teeth arranged at intervals along the circumferential direction of the seventh tooth segment 441. The eighth tooth segment 442 includes a plurality of twelfth tooth portions 4421 arranged at intervals along the circumferential direction of the eighth tooth segment 442. The specific structure of the fourth gear 44 can refer to the description of the first gear 41, which will not be repeated here.

[0181] The fourth gear 44 is arranged on the side of the third gear 43 away from the second gear 42, the sixth tooth portion 4411 is engaged with the eighth tooth portion 4312, and the twelfth tooth portion 4421 is engaged with the eleventh tooth portion 4322. When the first rotating rod 471 rotates relative to the base 10, the first gear 41 is driven to rotate, the second gear 42 is driven to rotate by the first gear 41, the third gear 43 is driven to rotate by the second gear 42, and the fourth gear 44 is driven to rotate by the third gear 43, thereby driving the fourth rotating rod 474 to rotate. Alternatively, when the fourth rotating rod 474 rotates relative to the base 10, the fourth gear 44 is driven to rotate, the third gear 43 is driven to rotate by the fourth gear 44, the second gear 42 is driven to rotate by the third gear 43, and the first gear 41 is driven to rotate by the second gear 42, thereby driving the first rotating rod 471 to rotate.

[0182] In the embodiment, the eighth tooth portion 4312 and the eleventh tooth portion 4322 of the third gear 43 are misaligned, and the sixth tooth portion 4411 and the twelfth tooth portion 4421 of the fourth gear 44 are misaligned. During the relative rotation of the third gear 43 and the fourth gear 44, when the eighth tooth portion 4312 is engaged with the sixth tooth portion 4411 and has not disengaged from the sixth tooth portion 4411, the eleventh tooth portion 4322 is engaged with the twelfth tooth portion 4421; when the eleventh tooth portion 4322 is engaged with the twelfth tooth portion 4421 and has not disengaged from the twelfth tooth portion 4421, the eighth tooth portion 4312 is engaged with the sixth tooth portion 4411 again. That is, during the relative rotation of the third gear 43 and the fourth gear 44, the eighth tooth portion 4312 and the sixth tooth portion 4411 are engaged, and the eleventh tooth portion 4322 and the twelfth tooth portion 4421 are engaged, so that the coincidence degree of the synchronous gear 40 can be improved, and the transmission stability between the third gear 43 and the fourth gear 44 can be improved. In the embodiment, the coincidence degree between the third gear 43 and the fourth gear 44 is greater than 1. For example, the coincidence degree between the third gear 43 and the fourth gear 44 is 1.2.

[0183] In the embodiment, the radius of the addendum circle of the eighth tooth portion 4312 is greater than the radius of the addendum circle of the sixth tooth portion 4411, and the radius of the addendum circle of the eleventh tooth portion 4322 is greater than the radius of the addendum circle of the twelfth tooth portion 4421. When the third gear 43 and the fourth gear 44 rotate simultaneously, the angle of rotation of the eighth tooth portion 4312 is less than the angle of rotation of the sixth tooth portion 4411, and the angle of rotation of the eleventh tooth portion 4322 is less than the angle of rotation of the twelfth tooth portion 4421, that is, the angle of rotation of the third gear 43 is less than the angle of rotation of the fourth gear 44, so that the required avoidance space of the eighth tooth portion 4312 and the eleventh tooth portion 4322 during rotation can be reduced, and the utilization rate of the space around the eighth tooth portion 4312 and the eleventh tooth portion 4322, that is, the utilization rate of the space around the third gear 43, can be improved.

[0184] It should be noted that the four tooth portions engaged in sequence along the X direction can be regarded as a gear set. The synchronous gear 40 includes multiple gear sets. Here, "multiple" refers to two or three or more. In the embodiment, the synchronous gear 40 includes two gear sets. The two gear sets are a first gear set 401 and a second gear set 402. The first gear set 401 includes the first tooth portion 411, the third tooth portion 421, the fifth tooth portion 431, and the seventh tooth portion 441. The second gear set 402 includes the second tooth portion 412, the fourth tooth portion 422, the sixth tooth portion 432, and the eighth tooth portion 442. The first gear set 401 and the second gear set 402 are misaligned, that is, the tooth of the first gear set 401 is at least partially misaligned with the tooth of the second gear set 402 in the orthogonal projection along the Y direction.

[0185] In other embodiments, the synchronization gear 40 can also include three, four or more groups of gears to further improve the coincidence degree of the synchronization gear 40, thereby further improving the transmission continuity and stability of the synchronization gear 40. At least two groups of gears in the multiple groups of gears are arranged with a phase difference, or any two groups of gears can be arranged with a phase difference. The phase difference between the two groups of gears arranged with a phase difference is greater than 0 and less than or equal to 1, which can be designed according to the parameters of the gears.

[0186] Referring to FIG. 20, FIG. 20 is a partially exploded structural schematic view of the synchronization assembly 1 shown in FIG. 13.

[0187] The damping member 50 includes a third fixed seat 51, a hinged seat 52 and an elastic member 53. The hinged seat 52 is provided with two third mounting holes 523. The two third mounting holes 523 penetrate the hinged seat 52 along the thickness direction of the hinged seat 52, that is, along the Y direction. The hinged seat 52 is provided with a first concave-convex wheel 521 and a second concave-convex wheel 522. The first concave-convex wheel 521 and the second concave-convex wheel 522 are arranged on the same side of the hinged seat 52 and surround the two third mounting holes 523, respectively.

[0188] The hinged seat 52 is mounted on the first rotating rod 471 and the fourth rotating rod 474 and can move along the Y direction relative to the first rotating rod 471 and the fourth rotating rod 474. The hinged seat 52 is located on the side of the second fixed seat 46 away from the synchronization gear 40 and is spaced apart from the second fixed seat 46 along the Y direction, and the first concave-convex wheel 521 and the second concave-convex wheel 522 face the second fixed seat 46. Specifically, the first rotating rod 471 and the fourth rotating rod 474 are respectively arranged in the two third mounting holes 523 of the hinged seat 52.

[0189] The third fixed seat 51 is spaced apart from the hinged seat 52 along the Y direction and is located on the side of the hinged seat 52 away from the synchronization gear 40. The third fixed seat 51 is fixedly connected with the first rotating rod 471 and the fourth rotating rod 474. Specifically, the third fixed seat 51 is provided with two mounting holes, and the first rotating rod 471 and the fourth rotating rod 474 are respectively arranged in the two mounting holes of the third fixed seat 51.

[0190] The elastic member 53 is arranged between the hinged seat 52 and the third fixed seat 51, and the elastic compression direction of the elastic member 53 is parallel or substantially parallel to the Y direction. Along the length direction of the elastic member 53, one end of the elastic member 53 is abutted or fixedly connected with the hinged seat 52, and the other end is abutted or fixedly connected with the third fixed seat 51.

[0191] In this embodiment, the elastic member 53 is a coil spring. There can be one or multiple coil springs. When there are multiple coil springs, one of the coil springs is sleeved on the outer periphery of the first rotating rod 471, and another coil spring is sleeved on the outer periphery of the fourth rotating rod 474. In order to further enhance the elastic restoring force of the elastic member 53, a coil spring can be additionally arranged between the two coil springs. For example, a fixed shaft can be arranged between the third fixed seat 51 and the hinged seat 52, and the coil spring arranged in the middle is sleeved on the outer periphery of the fixed shaft, so as to realize the installation of the coil spring arranged in the middle. In other embodiments, in order to further enhance the elastic restoring force of the elastic member 53, two or even three or more springs can be additionally arranged between the two coil springs.

[0192] In an embodiment, the elastic member 53 can also be a flat spring with a snake-shaped structure, so as to reduce the size of the elastic member 53 in the Z direction. Alternatively, the elastic member 53 can also be other elastic structures 93. Here, the structure and material of the elastic member 53 are not specifically limited, as long as the elastic member 53 can provide an elastic force in the Y direction.

[0193] Please refer to FIG. 14 and FIG. 21, which is a structural schematic diagram of the first swing arm 61 and the second swing arm 62 in the synchronization assembly 1 shown in FIG. 13.

[0194] The first swing arm 61 comprises a first rotating part 611, a first sliding part 612 and a first sliding shaft 613. The first rotating part 611 and the first sliding part 612 are connected along the length direction of the first swing arm 61. When the rotating shaft mechanism 100 is in the unfolded state, the length direction of the first swing arm 61 is parallel or substantially parallel to the X direction. The first rotating part 611 is provided with a first rotating hole 614. The axis direction of the first rotating hole 614 is parallel to the width direction of the first swing arm 61, that is, parallel to the Y direction. The inner surface of the first rotating hole 614 comprises a planar part and an arc surface part. The planar part and the arc surface part are connected along the circumferential direction of the first rotating hole 614. Moreover, the shape of the first rotating hole 614 is adapted to the shape of the first flat shaft segment 4711. Here, “adapted” means that the outer contour of the first rotating hole 614 is consistent with the outer contour of the first flat shaft segment 4711, and when the first flat shaft segment 4711 is installed in the first rotating hole 614, the fixed connection between the first flat shaft segment 4711 and the first swing arm 61 can be realized. The side surface of the first rotating part 611 is provided with a third concave-convex wheel 615. The third concave-convex wheel 615 is arranged around the outer periphery of the first rotating hole 614, and is used for hinging with the first concave-convex wheel 521 of the damping member 50.

[0195] The first sliding part 612 is used for sliding connection with the first fixed frame 21. The first sliding part 612 is in a plate structure. In the embodiment, the first sliding part 612 comprises two sub sliding bodies. The two sub sliding bodies are arranged in the Y direction. The first sliding shaft 613 is connected to the side surface of the first sliding part 612, and the extension direction of the first sliding shaft 613 is parallel to the Y direction. In the embodiment, the first sliding shaft 613 is two. The two first sliding shafts 613 are respectively connected to the side surfaces of the two sub sliding bodies and are located in the gap between the two sub sliding bodies. The first sliding shaft 613 is used for rotating and sliding connection with the first door plate 81.

[0196] The second swing arm 62 is a mirror image symmetric structure with the first swing arm 61. The second swing arm 62 comprises a second rotating part 621, a second sliding part 622 and a second sliding shaft 623. The second rotating part 621 and the second sliding part 622 are connected along the length direction of the second swing arm 62. The second rotating part 621 is provided with a second rotating hole 624. The axis direction of the second rotating hole 624 is parallel to the Y direction. The shape of the second rotating hole 624 is matched with the shape of the second flat shaft section 4741. The second rotating hole 624 is used for mounting the second flat shaft section 4741, so that the second swing arm 62 is fixedly connected with the fourth rotating rod 474. The side surface of the second rotating part 621 is provided with a fourth concave-convex wheel 625. The fourth concave-convex wheel 625 is arranged around the outer periphery of the second rotating hole 624 and is used for hinged connection with the second concave-convex wheel 522 of the damping part 50.

[0197] The second sliding part 622 is used for sliding connection with the second fixed frame 22. In the embodiment, the second sliding part 622 comprises two sub sliding bodies. The two sub sliding bodies are arranged in the Y direction. The second sliding shaft 623 is connected to the side surface of the second sliding part 622, and the extension direction of the second sliding shaft 623 is parallel to the Y direction. In the embodiment, the second sliding shaft 623 is two. The two second sliding shafts 623 are respectively connected to the side surfaces of the two sub sliding bodies of the second sliding part 622 and are located in the gap between the two sub sliding bodies. The second sliding shaft 623 is used for rotating and sliding connection with the second door plate 82.

[0198] Please combine FIG. 22 and FIG. 23. FIG. 22 is a partial structure schematic diagram of the rotating shaft mechanism 100 shown in FIG. 5, and FIG. 23 is a sectional structure schematic diagram of the rotating shaft mechanism 100 shown in FIG. 5.

[0199] The synchronous assembly 1 is arranged on the base 10. The first fixing seat 45, the second fixing seat 46, the rotating rod 47, the synchronous gear 40 and the damping member 50 are located in the mounting groove 15. The first fixing seat 45, the second fixing seat 46 and the third fixing seat 51 are fixedly connected with the base 10. The axial direction of the rotating rod 47 and the axial direction of the synchronous gear 40 are parallel to the Y direction, and the rotating rod 47 and the synchronous gear 40 can rotate relative to the first fixing seat 45 and the second fixing seat 46, thereby rotating relative to the base 10. The first swing arm 61 is located on the negative side of the X axis of the base 10 and is arranged in the Y direction away from the first main swing arm 31. The first swing arm 61 is sleeved on the outer periphery of the first rotating rod 471 and is fixedly connected with the first rotating rod 471 and is located between the second fixing seat 46 and the hinge seat 52.

[0200] The first rotating part 611 is sleeved on the outer periphery of the first flat shaft section 4711 and is fixedly connected with the first flat shaft section 4711. The first flat shaft section 4711 is located in the first rotating hole 614, the planar part of the first flat shaft section 4711 is arranged opposite to the planar part of the first rotating hole 614, and the arc surface part of the first flat shaft section 4711 is arranged opposite to the arc surface part of the first rotating hole 614. In this way, the fixed connection between the first swing arm 61 and the first rotating rod 471 can be achieved without additional fixed elements, and the structure of the rotating shaft mechanism 100 can be simplified. The third concave-convex wheel 615 faces the first concave-convex wheel 521 and is hingedly connected with the first concave-convex wheel 521.

[0201] The first sliding part 612 is arranged in the first sliding groove 211 of the first fixing frame 21 and can slide along the first sliding groove 211. Specifically, the two sub-sliding bodies of the first sliding part 612 are arranged in the two sub-slots of the first sliding groove 211, and each sub-sliding body can slide along the corresponding sub-slot. The first sliding shaft 613 is arranged corresponding to the first avoiding groove 214 and is used for rotating and sliding connection with the first door plate 81. For example, the first sliding shaft 613 is located in the first avoiding groove 214 or partially located in the first avoiding groove 214. Alternatively, the first sliding shaft 613 can be located outside the first avoiding groove 214 and arranged opposite to the first avoiding groove 214.

[0202] The second swing arm 62 is located on the positive direction of the X axis of the base 10 and is spaced apart from the second main swing arm 32 along the Y direction. The second swing arm 62 is sleeved on the outer periphery of the fourth rotating rod 474 and is fixedly connected with the fourth rotating rod 474 and is located between the second fixed seat 46 and the hinged seat 52. Specifically, the second flat shaft section 4741 is located in the second rotating hole 624, the flat surface part of the second flat shaft section 4741 is oppositely arranged with the flat surface part of the second rotating hole 624, and the arc surface part of the second flat shaft section 4741 is oppositely arranged with the arc surface part of the second rotating hole 624. The fourth concave-convex wheel 625 faces the second concave-convex wheel 522 and is hinged with the second concave-convex wheel 522. The second sliding part 622 is arranged in the fourth sliding groove 221 of the second fixed frame 22 and can slide along the fourth sliding groove 221. The second sliding shaft 623 is correspondingly arranged with the second avoiding groove 224.

[0203] Please refer to FIG. 24 and FIG. 25, FIG. 24 is another sectional structure schematic diagram of the rotating shaft mechanism 100 shown in FIG. 5, and FIG. 25 is a sectional structure schematic diagram of the rotating shaft mechanism 100 shown in FIG. 24 in a folded state.

[0204] When the rotating shaft mechanism 100 is in an unfolded state, the first fixed frame 21 and the second fixed frame 22 are unfolded relative to each other, and the first swing arm 61 and the second swing arm 62 are unfolded relative to each other. The included angle between the first swing arm 61 and the second swing arm 62 is substantially 180°. When the rotating shaft mechanism 100 is in a folded state, the first fixed frame 21 and the second fixed frame 22 are folded relative to each other, and the first swing arm 61 and the second swing arm 62 are folded relative to each other. The first swing arm 61 and the second swing arm 62 are parallel or substantially parallel.

[0205] During the process that the rotating shaft mechanism 100 rotates from the unfolded state to the folded state, the first fixed frame 21 and the second fixed frame 22 rotate towards the direction of relatively close. That is, the first fixed frame 21 rotates in the clockwise direction, and the second fixed frame 22 rotates in the counterclockwise direction. When the first fixed frame 21 rotates in the clockwise direction, the first sliding part 612 drives the first swing arm 61 to rotate in the clockwise direction, and the second sliding part 622 slides along the first sliding groove 211. When the first swing arm 61 rotates in the clockwise direction, the first rotating part 611 drives the first rotating rod 471 to rotate in the clockwise direction, so as to drive the first gear 41 to rotate in the clockwise direction, and the first gear 41 drives the second gear 42 to rotate in the counterclockwise direction, the second gear 42 drives the third gear 43 to rotate in the clockwise direction, and the third gear 43 drives the fourth gear 44 to rotate in the counterclockwise direction. When the fourth gear 44 rotates in the counterclockwise direction, the fourth rotating rod 474 rotates in the counterclockwise direction, so as to drive the second swing arm 62 to rotate in the counterclockwise direction through the second rotating part 621. When the second swing arm 62 rotates in the counterclockwise direction, the second fixed frame 22 rotates in the counterclockwise direction, and the second sliding part 622 slides along the fourth sliding groove 221, so as to realize the synchronous rotation of the first swing arm 61 and the second swing arm 62, and the synchronous rotation of the first fixed frame 21 and the second fixed frame 22, that is, the synchronous rotation of the rotating shaft mechanism 100 and the foldable electronic device 500.

[0206] During the process that the rotating shaft mechanism 100 rotates from the folded state to the unfolded state, the first fixed frame 21 and the second fixed frame 22 rotate towards the direction of relatively far away. That is, the first fixed frame 21 rotates in the counterclockwise direction, and the second fixed frame 22 rotates in the clockwise direction. When the first fixed frame 21 rotates in the counterclockwise direction, the first sliding part 612 drives the first swing arm 61 to rotate in the counterclockwise direction. When the first swing arm 61 rotates in the counterclockwise direction, the first rotating part 611 drives the first rotating rod 471 and the first gear 41 to rotate in the counterclockwise direction, so as to drive the second gear 42 to rotate in the clockwise direction, the second gear 42 drives the third gear 43 to rotate in the counterclockwise direction, and the third gear 43 drives the fourth gear 44 to rotate in the clockwise direction. When the fourth gear 44 rotates in the clockwise direction, the fourth rotating rod 474 rotates in the clockwise direction, so as to drive the second swing arm 62 to rotate in the clockwise direction, and then drive the second fixed frame 22 to rotate in the clockwise direction, so as to realize the synchronous rotation of the rotating shaft mechanism 100 and the foldable electronic device 500.

[0207] Meanwhile, in the rotating process of the rotating shaft mechanism 100, the first swing arm 61 and the second swing arm 62 rotate relative to the base 10, the third cam wheel 615 repeatedly presses the first cam wheel 521, and the fourth cam wheel 625 repeatedly presses the second cam wheel 522, so as to make the hinged seat 52 reciprocate along the Y direction, and repeatedly press the elastic member 53, so as to compress the elastic member 53 and generate an elastic restoring force. The elastic restoring force acts on the hinged seat 52 in turn, and the hinged seat 52 applies a damping force to the rotation of the first swing arm 61 through the first cam wheel 521, so as to apply a damping force to the rotation of the first fixed frame 21. Moreover, the hinged seat 52 applies a damping force to the second swing arm 62 through the second cam wheel 522, so as to apply a damping force to the rotation of the second fixed frame 22, and further provide a damping force for the rotation of the rotating shaft mechanism 100 and the rotation of the foldable electronic device 500, so as to realize the hovering of the foldable electronic device 500, and improve the damping feeling for the user, so as to improve the user experience.

[0208] Please refer to FIG. 26, which is a structural schematic diagram of the support plate 70 in the rotating shaft mechanism 100 shown in FIG. 5.

[0209] The support plate 70 is a long strip-shaped plate body. The support plate 70 comprises a first surface 71 and a second surface 72. The first surface 71 and the second surface 72 are oppositely arranged along the thickness direction of the support plate 70. The first surface 71 is provided with an avoiding groove 73. The avoiding groove 73 is located in the middle region of the first surface 71 in the X direction, and extends along the Y direction. The avoiding groove 73 is arc-shaped along the XZ direction cross section, and curves towards the second surface 72. That is, from the opposite two ends to the center direction in the X direction, the distance between the groove bottom wall of the avoiding groove 73 and the second surface 72 gradually decreases. The avoiding groove 73 is used for avoiding the bendable part 350 of the display screen 300.

[0210] The support plate 70 is further provided with a first through groove 74, a second through groove 75, a first notch 76 and a second notch 77. The first through groove 74 and the second through groove 75 penetrate through the first surface 71 and the second surface 72 along the Z direction. The first through groove 74 and the second through groove 75 are arranged side by side along the X direction, and the first through groove 74 is used for avoiding the first main swing arm 31, and the second through groove 75 is used for avoiding the second main swing arm 32.

[0211] The first notch 76 is arranged in the Y direction and spaced apart from the first through groove 74. The first notch 76 is used for avoiding the first swing arm 61. The second notch 77 is arranged in the Y direction and spaced apart from the second through groove 75, and is opposite to and spaced apart from the first notch 76 in the X direction. The second notch 77 is used for avoiding the second swing arm 62.

[0212] Please refer to FIG. 27, which is a partial structural schematic diagram of the rotating shaft mechanism 100 shown in FIG. 5.

[0213] The support plate 70 is stacked with the base 10 along the Z direction and is fixedly connected with the base 10. The second surface 72 of the support plate 70 faces the base 10. The first rotating part 611 of the first swing arm 61 is exposed by the first notch 76, and the second rotating part 621 of the second swing arm 62 is exposed by the second notch 77. When the rotating shaft mechanism 100 is in the unfolded state, the end of the first main swing arm 31 away from the first fixed frame 21 is exposed by the first through slot 74, and the end of the second main swing arm 32 away from the second fixed frame 22 is exposed by the second through slot 75, so as to avoid the first main swing arm 31 and the second main swing arm 32 abutting against the support plate 70 during rotation, thereby improving the connection stability of the support plate 70 and the base 10. For example, the support plate 70 and the base 10 are fixedly connected by bolts. Alternatively, the support plate 70 can also be fixedly connected with the base 10 by clamping, welding, bonding or other ways.

[0214] The mounting groove 15 is formed between the support plate 70 and the base 10. The synchronous gear 40 and the damping part 50 are located in the mounting groove 15, and the support plate 70 covers the synchronous gear 40. That is, the orthogonal projection of the support plate 70 along the Z direction completely covers the synchronous gear 40. It can be understood that the base 10, the synchronous gear 40 and the support plate 70 are sequentially stacked along the Z direction. Among them, the second gear 42 and the third gear 43 in the synchronous gear 40 are oppositely arranged with the avoiding groove 73 of the support plate 70. The orthogonal projection of the groove bottom wall of the avoiding groove 73 along the Z direction at least partially covers the second gear 42 and the third gear 43. That is, the third gear 43 and the second gear 42 are located on the side of the Z axis negative direction of the avoiding groove 73.

[0215] The display screen 300 is installed on the side of the rotating shaft mechanism 100 close to the support plate 70, and the bendable part 350 of the display screen 300 is oppositely arranged with the support plate 70. When the rotating shaft mechanism 100 is in the unfolded state, the support plate 70 plays a supporting role for the bendable part 350. When the rotating shaft mechanism 100 is in the folded state, the bendable part 350 bends towards the direction of the avoiding groove 73. The avoiding groove 73 plays an avoiding role for the display screen 300, so as to avoid the support plate 70 from pressing the display screen 300, thereby improving the display effect of the display screen 300 and prolonging the service life of the display screen 300.

[0216] Please combine Figure 24 and Figure 25, during the process of rotating the rotating shaft mechanism 100 from the folded state to the unfolded state, the second gear 42 rotates in the clockwise direction, the second tooth part 4211 and the fifth tooth part 4221 rotate towards the direction close to the support plate 70; the third gear 43 rotates in the counterclockwise direction, the eighth tooth part 4312 and the eleventh tooth part 4322 rotate towards the direction close to the support plate 70. When the rotating shaft mechanism 100 is in the unfolded state, the second tooth part 4211 and the fifth tooth part 4221 of the second gear 42 are towards the support plate 70, and the eighth tooth part 4312 and the eleventh tooth part 4322 of the third gear 43 are towards the support plate 70.

[0217] In the embodiment of the present application, by setting the radius of the addendum circle of the second tooth part 4211 of the second gear 42 to be greater than the radius of the addendum circle of the first tooth part 4111 of the first gear 41, the rotation angle of the second tooth part 4211 during rotation of the rotating shaft mechanism 100 can be reduced, thereby the required avoidance space of the second tooth part 4211 during rotation can be reduced, and the utilization rate of the space around the second tooth part 4211 can be improved to avoid interference between the second tooth part 4211 and the support plate 70, and the structural stability of the support plate 70 is improved. Moreover, when the thickness of the rotating shaft mechanism 100 meets the requirements, the thickness of the position on the support plate 70 opposite to the second tooth part 4211 can be increased, that is, the thickness of the narrow neck area of the support plate 70 can be increased, thereby the strength of the support plate 70 can be improved, and the supporting effect of the support plate 70 on the display screen 300 is improved, so that the display screen 300 has better display effect. It should be noted that the "narrow neck area of the support plate 70" is the area of the support plate 70 provided with the avoidance groove 73.

[0218] At the same time, since the required avoidance space of the second tooth part 4211 during rotation is smaller, it is not necessary to set a hollow part on the support plate 70 corresponding to the third gear 43 to avoid the second tooth part 4211, that is, it is not necessary to set a hole on the support plate 70 corresponding to the synchronous gear 40, so that the support plate 70 can be set to completely cover the synchronous gear 40 in the Z direction. In this way, the structural strength of the support plate 70 can be improved, and the second tooth part 4211 can be prevented from abutting against the display screen 300 to cause extrusion to the display screen 300, and the display screen 300 can be prevented from being directly contacted with the synchronous gear 40 when the display screen 300 is contacted with a stylus or a sharp object, so that the display screen 300 is not damaged, the reliability of the display screen 300 is improved, the supporting effect of the support plate 70 on the display screen 300 is improved, the flatness of the display screen 300 and the display effect of the display screen 300 are further improved, and the service life of the display screen 300 is improved.

[0219] Similarly, in the embodiment of the present application, by setting the radius of the addendum circle of the fifth tooth part 4221 of the second gear 42 to be greater than the radius of the addendum circle of the fourth tooth part 4121 of the first gear 41, the rotation angle of the fifth tooth part 4221 during rotation of the rotating shaft mechanism 100 can be reduced, so that the required avoidance space of the fifth tooth part 4221 during rotation can be reduced, and the utilization rate of the space around the fifth tooth part 4221 can be improved. In this way, interference between the fifth tooth part 4221 and the support plate 70 can be avoided, the structural stability of the support plate 70 can be improved, and the thickness of the position on the support plate 70 opposite to the fifth tooth part 4221 can be increased, so that a hollow part corresponding to the fifth tooth part 4221 on the support plate 70 is not required, and the structural strength of the support plate 70 can be further improved.

[0220] In the embodiment of the present application, by setting the radius of the addendum circle of the eighth tooth part 4312 of the third gear 43 to be greater than the radius of the addendum circle of the sixth tooth part 4411 of the fourth gear 44, and setting the radius of the addendum circle of the eleventh tooth part 4322 to be greater than the radius of the addendum circle of the twelfth tooth part 4421, the rotation angle of the third gear 43 can be reduced, that is, the rotation angles of the eighth tooth part 4312 and the eleventh tooth part 4322 can be reduced, so that the required avoidance space of the third gear 43 during rotation can be reduced, and the utilization rate of the space around the third gear 43 can be improved. In this way, interference between the third gear 43 and the support plate 70 can be avoided, the structural stability of the support plate 70 can be improved, and the thickness of the position on the support plate 70 opposite to the third gear 43 can be increased, so that a hollow part corresponding to the third gear 43 on the support plate 70 is not required, and the structural strength of the support plate 70 can be further improved.

[0221] It can be understood that, in the embodiment of the present application, by setting the radius of the addendum circle of the tooth part of the second gear 42 engaged with the first gear 41 to be greater than the radius of the addendum circle of the tooth part of the first gear 41, and by setting the radius of the addendum circle of the tooth part of the third gear 43 engaged with the fourth gear 44 to be greater than the radius of the addendum circle of the tooth part of the fourth gear 44, the required avoidance space of the second gear 42 and the third gear 43 during rotation can be reduced, so that the utilization rate of the space around the second gear 42 and the third gear 43 can be reduced, and more space can be provided for the support plate 70. In this way, interference between the synchronous gear 40 and the support plate 70 can be avoided, a hollow part can be avoided on the support plate 70 to avoid the synchronous gear 40, and the thickness of the support plate 70 in the narrow neck area can be increased, so that the strength of the support plate 70 can be improved, the structural stability of the rotating shaft mechanism 100 and the foldable electronic device 500 can be improved, and the display effect and service life of the display screen 300 can be improved.

[0222] Exemplarily, the thickness of the rotating shaft mechanism 100 at the thinnest position is 2.0mm-2.6mm. The thinnest position is the position where the avoiding groove 73 is arranged. That is to say, the dimension of the rotating shaft mechanism 100 along the Z direction at the position corresponding to the avoiding groove 73 is 2.0mm-2.6mm.

[0223] As shown in FIG. 24, when the rotating shaft mechanism 100 is in the unfolded state, the second tooth part 4211 and the fifth tooth part 4221 in the second gear 42 are towards the support plate 70, and the eighth tooth part 4312 and the eleventh tooth part 4322 in the third gear 43 are towards the support plate 70. The third tooth part 4212 and the ninth tooth part 4222 in the second gear 42 are towards the base 10, and the seventh tooth part 4311 and the tenth tooth part 4321 in the third gear 43 are towards the base 10.

[0224] In an embodiment, the meshing teeth of the second tooth part 4211 close to the support plate 70 are half teeth, so as to avoid interference between the second tooth part 4211 and the support plate 70, thereby improving the stability of the support plate 70, and the smoothness and stability of the synchronous gear 40 rotating. Exemplarily, one of the meshing teeth of the second tooth part 4211 close to the third tooth part 4212 is a half tooth. Alternatively, both of the meshing teeth of the second tooth part 4211 close to the third tooth part 4212 can be half teeth. The half tooth is obtained by cutting the top part of a complete meshing tooth. The height of the half tooth is smaller than that of the complete meshing tooth. Similarly, one or more meshing teeth of the fifth tooth part 4221 close to the support plate 70 can also be half teeth, so as to avoid interference between the fifth tooth part 4221 and the support plate 70. One or more meshing teeth of the eighth tooth part 4312 in the third gear 43 close to the support plate 70 can be half teeth, so as to avoid interference between the eighth tooth part 4312 and the support plate 70. One or more meshing teeth of the eleventh tooth part 4322 in the third gear 43 close to the support plate 70 can be half teeth, so as to avoid interference between the eleventh tooth part 4322 and the support plate 70.

[0225] In an embodiment, the meshing teeth of the eighth tooth part 4312 of the third gear 43 close to the support plate 70 are half teeth, and the meshing teeth of the eleventh tooth part 4322 close to the support plate 70 are half teeth, so as to avoid interference between the third gear 43 and the support plate 70, thereby improving the stability of the support plate 70, and the smoothness of the third gear 43 rotating.

[0226] In an embodiment, the meshing teeth of the seventh tooth part 4311 towards the base 10, and the meshing teeth of the tenth tooth part 4321 towards the base 10 are half teeth, so as to avoid interference between the meshing teeth in the third gear 43 and the base 10.

[0227] In one embodiment, the teeth of the third tooth portion 4212 facing the base 10 and the teeth of the ninth tooth portion 4222 facing the base 10 are half teeth, so that interference between the teeth of the second gear 42 and the base 10 can be avoided.

[0228] Referring to FIGS. 28 and 29, FIG. 28 is a partially exploded structural schematic view of the rotating shaft mechanism 100 shown in FIG. 5, and FIG. 29 is a partially structural schematic view of the first door panel 81 and the second door panel 82 in the rotating shaft mechanism 100 shown in FIG. 28.

[0229] The first door panel 81 and the second door panel 82 are both long strip-shaped panel bodies. The back surface of the first door panel 81 is provided with first guide sliding blocks 811. The first guide sliding blocks 811 are arc-shaped sliding blocks and extend away from the first door panel 81. The shape of the first guide sliding blocks 811 matches the structure of the third sliding grooves 213 on the first fixed frame 21. Here, “match” means that the first guide sliding blocks 811 can be installed in the third sliding grooves 213 and slide along the third sliding grooves 213. There are a plurality of first guide sliding blocks 811. The plurality of first guide sliding blocks 811 are arranged at intervals along the length direction of the first door panel 81. The plurality of first guide sliding blocks 811 are arranged in one-to-one correspondence with the plurality of third sliding grooves 213. The back surface of the first door panel 81 is further provided with a first guide groove 812 and a second guide groove 813. The first guide groove 812 is a strip-shaped groove. The first guide groove 812 is used to be rotatably and slidably connected with the first main swing arm 31. The second guide groove 813 is an arc-shaped groove. The structure of the second guide groove 813 matches the first sliding shaft 613 of the first swing arm 61, and the first sliding shaft 613 can rotate and slide along the second guide groove 813 relative to the first door panel 81.

[0230] The second door panel 82 is mirror-symmetrically structured with the first door panel 81. The back surface of the second door panel 82 is provided with arc-shaped second guide sliding blocks 821. The second guide sliding blocks 821 are used to be installed in the sixth sliding grooves 223 of the second fixed frame 22 and can slide and rotate along the sixth sliding grooves 223. The back surface of the second door panel 82 is further provided with a third guide groove 822 and a fourth guide groove 823. The third guide groove 822 is used to be rotatably and slidably connected with the second main swing arm 32. The fourth guide groove 823 is an arc-shaped groove. The structure of the fourth guide groove 823 matches the second sliding shaft 623 of the second swing arm 62, and the second sliding shaft 623 can rotate and slide along the fourth guide groove 823 relative to the second door panel 82.

[0231] Please refer to Fig. 23, the first door plate 81 is stacked with the first fixed frame 21, and the first main swing arm 31 and the first swing arm 61 are both located between the first door plate 81 and the first fixed frame 21. The back of the first door plate 81 faces the first fixed frame 21. The first guide sliding block 811 is installed in the third sliding groove 213 and can slide along the third sliding groove 213. The first sliding shaft 613 of the first swing arm 61 is installed in the second guide groove 813 and can rotate and slide along the second guide groove 813. The hinge mechanism 100 further comprises a first hinge shaft 83. The first hinge shaft 83 is installed in the first shaft hole 315 of the first main swing arm 31 and is fixedly connected with the first main swing arm 31. The first hinge shaft 83 is installed in the first guide groove 812 of the first door plate 81 and can slide along the first guide groove 812 and rotate around the axis of the first hinge shaft 83.

[0232] The second door plate 82 is stacked with the second fixed frame 22, and the second main swing arm 32 and the second swing arm 62 are both located between the second door plate 82 and the second fixed frame 22. The back of the second door plate 82 faces the second fixed frame 22. The second guide sliding block 821 is installed in the sixth sliding groove 223 and can slide along the sixth sliding groove 223. The second sliding shaft 623 of the second swing arm 62 is installed in the fourth guide groove 823 and can rotate and slide along the fourth guide groove 823. The hinge mechanism 100 further comprises a second hinge shaft 84. The second hinge shaft 84 is installed in the second shaft hole 325 of the second main swing arm 32 and is fixedly connected with the second main swing arm 32. The second hinge shaft 84 is installed in the third guide groove 822 of the second door plate 82 and can slide along the third guide groove 822 and rotate around the axis of the second hinge shaft 84.

[0233] Please refer to Fig. 30 and Fig. 31, Fig. 30 is a sectional structure schematic diagram of the hinge mechanism 100 shown in Fig. 5, and Fig. 31 is a structure schematic diagram of the hinge mechanism 100 shown in Fig. 30 in a folded state. In Fig. 31, part of the structure of the display screen 300 is shown.

[0234] The display screen 300 is installed on the same side of the first door plate 81, the second door plate 82 and the support plate 70, that is, the display screen 300 is installed on the positive direction side of the Z axis of the hinge mechanism 100. The bendable part 350 is arranged opposite to the first door plate 81, the second door plate 82 and the support plate 70. When the hinge mechanism 100 is in an unfolded state, the first door plate 81 and the second door plate 82 are unfolded relative to each other and are located on opposite sides of the base 10 in the X direction. The top surface of the first door plate 81, the top surface of the second door plate 82 and the top surface of the support plate 70 are substantially in the same plane, that is, the top surface of the first door plate 81, the top surface of the second door plate 82 and the top surface of the support plate 70 are flush or substantially flush and jointly support the bendable part 350, so as to improve the flatness of the display screen 300 and make the display screen 300 have better display effect.

[0235] When the foldable electronic device 500 is rotated from the unfolded state to the folded state, the first housing 210 and the second housing 220 are rotated toward each other, and the first fixing frame 21 and the second fixing frame 22 are driven to rotate toward each other. When the first fixing frame 21 rotates relative to the base 10, the first door plate 81, the first main swing arm 31, and the first swing arm 61 are driven to rotate relative to the base 10, and the first guide sliding block 811 of the first door plate 81 slides along the third sliding groove 213, the first rotating shaft 83 slides and rotates along the first guide groove 812, and the first sliding shaft 613 slides and rotates along the second guide groove 813.

[0236] When the second fixing frame 22 rotates relative to the base 10, the second door plate 82, the second main swing arm 32, and the second swing arm 62 are driven to rotate relative to the base 10, and the second guide sliding block 821 of the second door plate 82 slides along the sixth sliding groove 223, the second rotating shaft 84 slides and rotates along the third guide groove 822, and the second sliding shaft 623 slides and rotates along the fourth guide groove 823.

[0237] As shown in FIG. 31, in the folded state, the first fixing frame 21 and the second fixing frame 22 are parallel and oppositely arranged along the X direction. The first door plate 81 and the second door plate 82 are oppositely arranged along the width direction of the base 10, and the first door plate 81 and the second door plate 82 are arranged at an angle. That is, the angle between the first door plate 81 and the second door plate 82 is greater than 0 degrees. Towards the base 10, the distance between the first door plate 81 and the second door plate 82 gradually increases, thereby forming a water droplet-shaped accommodation space between the first door plate 81, the second door plate 82, and the support plate 70. The bendable portion 350 of the display screen 300 is located in the accommodation space, and the bendable portion 350 is bent towards the avoiding groove 73 of the support plate 70.

[0238] In this embodiment, by rotatingly connecting the first door plate 81 and the first fixing frame 21, and slidingly connecting the first door plate 81 and the first main swing arm 31 and the first swing arm 61, and slidingly connecting the first door plate 81 and the first swing arm 61, and rotatingly connecting the second door plate 82 and the second fixing frame 22, and slidingly connecting the second door plate 82 and the second main swing arm 32 and the second swing arm 62, when the rotating shaft mechanism 100 rotates, the first door plate 81 can rotate relative to the first fixing frame 21, and the second door plate 82 can rotate relative to the second fixing frame 22, so that the angle between the first door plate 81 and the second door plate 82 can be adjusted, which is conducive to forming a water droplet-shaped accommodation space when the rotating shaft mechanism 100 is in the folded state, to adapt to the bending of the display screen 300, so that the display screen 300 can be prevented from being squeezed when the rotating shaft mechanism 100 is in the folded state, thereby prolonging the service life of the display screen 300, and also can reduce or even avoid the display screen 300 from having a crease, thereby improving the user's experience.

[0239] And, in the embodiment, the arc-shaped avoiding groove 73 is arranged on the support plate 70 to avoid the bendable part 350, so that the support plate 70 can avoid extruding the display screen 300, the display screen 300 can further reduce or avoid the creases, and the service life of the display screen 300 is improved.

[0240] The above are only some embodiments and implementation manners of the present application, and the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A rotating shaft mechanism, characterized in that, The base, the support plate, the first swing arm, the second swing arm and the synchronous gear are included. The synchronous gear includes a first gear, a second gear, a third gear and a fourth gear; the first gear includes a first tooth part, the second gear includes a second tooth part and a third tooth part, the second tooth part and the third tooth part are sequentially arranged along the circumference of the second gear, and the radius of the addendum circle of the second tooth part is greater than the radius of the addendum circle of the first tooth part; The first gear, the second gear, the third gear and the fourth gear are sequentially mounted on the base along the width direction of the base, the first tooth part is engaged with the second tooth part, the third tooth part is engaged with the third gear, and the third gear is engaged with the fourth gear; The support plate is arranged on the side of the synchronous gear away from the base and is fixedly connected with the base, and the support plate covers the synchronous gear in the thickness direction of the base; The first swing arm and the second swing arm are respectively arranged on opposite sides of the base in the width direction, and the first swing arm is fixedly connected with the first gear, and the second swing arm is fixedly connected with the fourth gear. The surface of the support plate away from the synchronous gear is provided with a relief groove, and the orthographic projection of the relief groove along the thickness direction of the base at least partially coincides with the second gear.

2. The rotation shaft mechanism according to claim 1, wherein The pitch circle diameter of the second tooth part is different from the pitch circle diameter of the third tooth part.

3. The rotation shaft mechanism according to claim 1, wherein The pitch circle diameter of the third tooth part is less than the pitch circle diameter of the second tooth part.

4. The rotation shaft mechanism according to claim 3, wherein The first gear further includes a fourth tooth part, the fourth tooth part is coaxially arranged with the first tooth part and is fixedly connected, and the meshing teeth of the fourth tooth part are at least partially misaligned with the meshing teeth of the first tooth part along the axial direction of the first gear; 5. The rotation shaft mechanism according to any one of claims 1 to 4, characterized in that, The second gear further includes a fifth tooth part, the fifth tooth part is coaxially arranged with the second tooth part and is fixedly connected, and the meshing teeth of the fifth tooth part are at least partially misaligned with the meshing teeth of the second tooth part along the axial direction of the second gear; the fifth tooth part is engaged with the fourth tooth part. The phase difference between the first tooth part and the fourth tooth part is greater than 0 and less than or equal to 1, and the phase difference between the second tooth part and the fifth tooth part is greater than 0 and less than or equal to 1.

6. The rotation shaft mechanism according to claim 5, wherein When the first gear rotates relative to the second gear, the first tooth part and the second tooth part are engaged at the same time, and the fourth tooth part and the fifth tooth part are engaged.

7. The rotation axis mechanism according to claim 6, wherein The synchronous gear includes a plurality of gear sets, and the plurality of gear sets are sequentially arranged along the length direction of the base; each gear set includes four gears sequentially engaged along the width direction of the base; and the meshing teeth of at least two gear sets are misaligned in the orthographic projection along the length direction of the base.

8. The rotation shaft mechanism according to claim 5, wherein At least one meshing tooth of the second tooth part towards the support plate is a half tooth.

9. The rotation shaft mechanism according to claim 5, wherein The fourth gear includes a sixth tooth part, the third gear includes a seventh tooth part and an eighth tooth part, and the seventh tooth part and the eighth tooth part are sequentially arranged along the circumference of the third gear; the radius of the addendum circle of the eighth tooth part is greater than the radius of the addendum circle of the sixth tooth part; the eighth tooth part is engaged with the sixth tooth part, and the seventh tooth part is engaged with the third tooth part.

10. The rotation shaft mechanism according to claim 5, wherein ​ 11. The rotation shaft mechanism according to claim 5, wherein The rotating shaft mechanism further comprises a first fixed frame and a second fixed frame, the first fixed frame is located on the same side of the base in the width direction, and the first fixed frame is slidably connected to the end of the first swing arm away from the base; the second fixed frame is located on the same side of the base in the width direction, and the second fixed frame is slidably connected to the end of the second swing arm away from the base.

12. The rotation mechanism according to claim 11, wherein The rotating shaft mechanism further comprises a first main swing arm and a second main swing arm, the first main swing arm is arranged in the length direction of the base and is spaced apart from the first swing arm, the first main swing arm is rotatably connected to the base and is rotatably connected to the first fixed frame; The second main swing arm is arranged in the length direction of the base and is spaced apart from the second swing arm, the second main swing arm is rotatably connected to the base and is rotatably connected to the second fixed frame.

13. The rotation mechanism according to claim 12, wherein The rotating shaft mechanism further comprises a first door plate and a second door plate; the first door plate is arranged in layers with the first fixed frame, and the first door plate is rotatably connected to the first fixed frame, and is rotatably and slidably connected to the first swing arm and the first main swing arm; the second door plate is arranged in layers with the second fixed frame, and the second door plate is rotatably connected to the second fixed frame, and is rotatably and slidably connected to the second swing arm and the second main swing arm; When the rotating shaft mechanism is in the folded state, the first door plate and the second door plate are oppositely arranged, and the distance between the first door plate and the second door plate gradually increases in the direction close to the support plate; When the rotating shaft mechanism is in the unfolded state, the first door plate and the second door plate are respectively located on opposite sides of the base in the width direction, and the top surface of the first door plate, the top surface of the second door plate and the top surface of the support plate are flush.

14. A foldable electronic device, characterized by The rotating shaft mechanism comprises a first shell, a second shell, a display screen and a rotating shaft mechanism according to any one of claims 1 to 13, the rotating shaft mechanism is connected between the first shell and the second shell, and the first swing arm is connected to the first shell and the second swing arm is connected to the second shell; The display screen is mounted on the first shell, the second shell and the rotating shaft mechanism, and the display screen is at least partially arranged opposite to the support plate.

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