CN114141151B

CN114141151B - Display device

Info

Publication number: CN114141151B
Application number: CN202111640094.5A
Authority: CN
Inventors: 周永红; 周鹏飞; 张崇; 祝尚杰; 谷朋浩; 许琳琳; 王新宇; 王博
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2021-07-07
Filing date: 2021-12-29
Publication date: 2023-11-10
Anticipated expiration: 2041-12-29
Also published as: CN113345334A; CN114141151A

Abstract

A display device relates to the technical field of display, and comprises a flexible display module and a middle frame assembly arranged on one side of the flexible display module, which is away from a display side; the middle frame assembly comprises a first frame body, a second frame body and a transmission assembly connected between the first frame body and the second frame body; the transmission assembly is arranged such that the second frame body can rotate relative to the first frame body to switch between a first folded state and a first flattened state; the transmission assembly is further arranged to drive the second frame to move in a direction approaching to the first frame in the process that the second frame rotates to the first folding state along the first direction; the surface of the flexible display module set, which is far away from the display side, is fixed on the first frame body and the second frame body. The display device disclosed by the embodiment of the disclosure can reduce the size of the frame.

Description

Display device

The present application claims priority from the chinese patent office, application No. 202110768304. X, chinese patent application entitled "a center assembly and display device" filed 7/2021, the contents of which are understood to be incorporated herein by reference.

Technical Field

The embodiment of the disclosure relates to the technical field of display, in particular to a display device.

Background

The foldable display device generally comprises a flexible display module and a middle frame assembly arranged on the back side of the flexible display module, wherein the length dimension of the middle frame assembly is unchanged, the flexible display module can generate a certain slippage when the display device is folded (inwards folded or outwards folded), and in order to cover the slippage of the flexible display module, the frame dimension of the display device can be larger, so that the narrow frame design cannot be realized.

Disclosure of Invention

The embodiment of the disclosure provides a display device, which comprises a flexible display module and a middle frame assembly arranged on one side of the flexible display module, which is away from a display side; the middle frame assembly comprises a first frame body, a second frame body and a transmission assembly connected between the first frame body and the second frame body; the transmission assembly is arranged such that the second frame body can rotate relative to the first frame body to switch between a first folded state and a first flattened state; the transmission assembly is further arranged to drive the second frame to move in a direction approaching to the first frame in the process that the second frame rotates to the first folding state along the first direction; the surface of the flexible display module set, which is far away from the display side, is fixed on the first frame body and the second frame body.

Optionally, the transmission assembly is further configured to drive the second frame to move in a direction away from the first frame in a process of rotating the second frame in a direction opposite to the first direction to the first flattened state.

Optionally, the transmission assembly includes a rotation shaft rotatably disposed on the first frame and a sliding member connected to the rotation shaft;

the sliding piece is provided with a sliding groove, the second frame body is provided with a sliding part, and the sliding part is arranged in the sliding groove in a sliding manner and slides along the sliding groove in the rotation process of the second frame body.

Optionally, the sliding piece comprises a first sliding piece and a second sliding piece, wherein the first sliding piece is fixedly connected with one end of the rotating shaft, and the second sliding piece is fixedly connected with the other end of the rotating shaft;

the sliding part comprises a first sliding part in sliding fit with the first sliding part and a second sliding part in sliding fit with the second sliding part.

Optionally, the second frame body includes a first side and a second side perpendicular to the axial direction of the rotating shaft and opposite to each other, the first side is provided with the first sliding portion, and the second side is provided with the second sliding portion.

Optionally, the transmission assembly further comprises a connecting member connected between the first frame and the second frame;

the connecting piece is arranged to be capable of being stuck to the rotating shaft for bending in the process of rotating the second frame body along the first direction, pulls the second frame body to move along the sliding groove in the direction close to the first frame body, and is arranged to be capable of being flattened and pushing the second frame body to move along the sliding groove in the direction far away from the first frame body in the process of rotating the second frame body along the opposite direction of the first direction.

Optionally, the connecting piece is a chain or a metal sheet, one end of the connecting piece is fixed on the first frame body, and the other end of the connecting piece is fixed on the second frame body.

Optionally, a first fixing groove is formed in the first frame body, a second fixing groove is formed in the second frame body, one end of the connecting piece is fixed in the first fixing groove, and the other end of the connecting piece is fixed in the second fixing groove.

Optionally, the connector is one or more; in the first flattened state, the extending direction of the connecting member is perpendicular to the axial direction of the rotating shaft.

Optionally, the connecting piece is a plurality of, and two adjacent connecting pieces are connected through the supporting layer, in the second framework rotation in-process the supporting layer can with the connecting piece is buckled together.

Optionally, the connecting member includes an elastic metal sheet, and a first protective layer and a second protective layer provided on opposite surfaces of the elastic metal sheet; one end of the connecting piece is fixed on the first frame body, and the other end of the connecting piece is fixed on the second frame body.

Optionally, the elastic metal sheet is made of stainless steel, aluminum alloy, titanium alloy or liquid metal memory alloy, the first protection layer is made of polyimide or polyethylene terephthalate, and the second protection layer is made of polyimide or polyethylene terephthalate.

Optionally, the connecting piece comprises a plurality of stacked elastic metal sheets, and two adjacent elastic metal sheets are bonded through an adhesive layer; one end of the connecting piece is fixed on the first frame body, and the other end of the connecting piece is fixed on the second frame body.

Optionally, the transmission assembly further includes a spring, the spring is disposed in the chute, and the spring is pressed by the sliding portion to elastically deform during rotation of the second frame along the first direction, and pushes the sliding portion to slide along the chute by self elastic force during rotation of the second frame along a direction opposite to the first direction.

Optionally, the transmission assembly further comprises a spring, the spring comprises a first spring part sleeved on the rotating shaft, a first folding leg is arranged at one end of the first spring part, a second folding leg is arranged at the other end of the first spring part, the first folding leg is fixed on the first frame, and the second folding leg is fixed on the second frame;

the first spring portion has a torsional force in the first folded state and is in a natural state in the first flattened state.

Optionally, the spring further comprises a second spring part, and a first end of the second spring part is connected with the second folding leg;

the second spring part is sleeved on a positioning column arranged on the second frame body, the second end of the second spring part is abutted against the second frame body, and the axial direction of the positioning column is perpendicular to the axial direction of the rotating shaft;

the second spring portion is in a compressed state in the first flattened state.

Optionally, a clamping groove is formed at one end of the sliding groove far away from the first frame body, the sliding part can slide into the clamping groove when the second frame body rotates to the first flattened state along the reverse direction of the first direction, and the sliding part can slide out of the clamping groove and slide along the sliding groove in the process that the second frame body rotates from the first flattened state along the first direction.

Optionally, the transmission assembly further includes a first gear disposed on the rotating shaft, a second gear disposed on the sliding member, a transmission belt sleeved on the first gear and the second gear, and a rack disposed on the second frame and meshed with the second gear.

Optionally, the transmission assembly further includes a first gear disposed on the rotating shaft, a second gear disposed on the sliding member, a transmission belt sleeved on the first gear and the second gear, a third gear coaxially disposed with the second gear, and a rack disposed on the second frame and meshed with the third gear.

Optionally, the first frame body is provided with a first magnetic piece, and the second frame body is provided with a second magnetic piece;

in the first folded state, the first frame body and the second frame body are locked through magnetic attraction between the first magnetic piece and the second magnetic piece.

Optionally, the middle frame assembly further includes a third frame rotationally connected to an end of the first frame away from the second frame and capable of being switched between a second folded state and a second flattened state; the surface of the flexible display module set, which is far away from the display side, is also fixed on the third frame body.

Optionally, the third frame is configured to be rotatable relative to the first frame in the first direction to the second folded state and rotatable in a direction opposite to the first direction to the second flattened state.

According to the display device, the second frame body of the middle frame assembly can move towards the direction close to the first frame body in the process of rotating to the folding state, so that the display device of the embodiment of the disclosure can reduce the size of the middle frame assembly in the process of folding outwards (bending outwards to the side away from the display side) through the second frame body, the tension can not be generated on the flexible display module in the process of folding outwards, and compared with the design scheme that the length size of the middle frame assembly of some foldable display devices is fixed, the display device of the embodiment of the disclosure can reduce the frame size of the display device.

Drawings

The accompanying drawings are included to provide a further understanding of the disclosed embodiments and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain, without limitation, the disclosed embodiments. The shapes and sizes of the components in the drawings do not reflect true proportions, and are intended to illustrate the present disclosure only.

Fig. 1 is a schematic view of a display device according to some exemplary embodiments in a folded state;

FIG. 2 is a schematic front view of the display device of FIG. 1 in a flattened state;

FIG. 3 is a schematic front view of the display device of FIG. 1 in a folded state;

FIG. 4 is a schematic front view of the display device of FIG. 1 in an folded-out state;

FIG. 5 is a schematic rear view of the display device of FIG. 1 in an folded-out state;

FIG. 6 is a schematic view of the display device of FIG. 1 in a flattened state;

FIG. 7 is a schematic front view of the display device of FIG. 6 in a folded state;

FIG. 8 is a schematic view of the structure of a center frame assembly of a display device in a flattened state according to some example embodiments;

FIG. 9 is a partial schematic view of the middle frame assembly of FIG. 8;

FIG. 10 is a partial schematic view of the middle frame assembly of FIG. 8 in a collapsed condition;

FIG. 11 is a schematic view of a partial exploded construction of the center frame assembly of FIG. 9;

FIG. 12 is a schematic view of a partially enlarged structure of FIG. 11;

FIG. 13 is a partial schematic view of a middle frame assembly of a display device according to other exemplary embodiments;

FIG. 14 is a partial schematic structural view of a middle frame assembly of a display device according to still other exemplary embodiments;

FIG. 15 is a partial schematic view of the middle frame assembly of FIG. 14 at the spring;

FIG. 16 is a partial structural schematic view of a middle frame assembly of a display device of still other exemplary embodiments;

FIG. 17 is a schematic view of a partial side elevational view of the center frame assembly of FIG. 16 in an outwardly folded condition;

FIG. 18 is a schematic cross-sectional view of a connector of the center frame assembly of FIG. 16 in some exemplary embodiments;

FIG. 19 is a schematic plan view of the resilient metal sheet of FIG. 18 in some exemplary embodiments;

FIG. 20 is a schematic cross-sectional view of a connector of the center frame assembly of FIG. 16 in further exemplary embodiments;

FIG. 21 is a partial schematic structural view of a middle frame assembly of a display device of still other exemplary embodiments;

FIG. 22 is a schematic structural view of a second slide of the center frame assembly of FIG. 21 in some exemplary embodiments;

FIG. 23 is a schematic front view of the second slider of FIG. 22;

fig. 24 is a partial structural schematic view of a middle frame assembly of a display device according to still other exemplary embodiments.

The reference numerals are:

10. the first frame body, 11, the first fixing groove, 20, the second frame body, 21, the first side edge, 22, the second side edge, 221, the second sliding part, 23, the second fixing groove, 231, the fixing hole, 232, the limit groove, 24, the positioning column, 25, the spring, 251, the first spring part, 252, the second spring part, 2511, the first folding leg, 2512, the second folding leg, 26, the spring, 30, the third frame body, 41, the rotating shaft, 42, the sliding member, 43, the connecting member, 431, the fixing column, 432, the limit part, 433, the fixing part, 434, the elastic sheet metal, 435, the first protective layer, 436, the second protective layer, 437, the adhesive layer, 44, the supporting layer, 421, the first sliding member, 422, the second sliding member, 4221, the second sliding groove, 4222, the second fixing hole, 4223, the second clamping groove, 4341, the through hole, 50, the flexible display module, 51, the end edge of the flexible display module, 501, the first bending region, 502, the second bending region, 61, the first gear, 62, the second gear, the third gear, the third gear, the belt, the gear, the transmission belt, the gear, and the transmission belt 65.

Detailed Description

It will be understood by those skilled in the art that modifications and equivalents may be made to the disclosed embodiments without departing from the spirit and scope of the disclosed embodiments, which are intended to be encompassed by the scope of the claims of the present disclosure.

As shown in fig. 1 to 5, fig. 1 is a schematic structural diagram of a display device in a folded state of some exemplary embodiments, fig. 2 is a schematic structural diagram of a front view of the display device in a flattened state of fig. 1, fig. 3 is a schematic structural diagram of a front view of the display device in a folded state of fig. 1, fig. 4 is a schematic structural diagram of a front view of the display device in an folded state of fig. 1, and fig. 5 is a schematic structural diagram of a rear view of the display device in an folded state of fig. 1. The display device is a foldable display device capable of being folded in three, and comprises a flexible display module 50 and a middle frame assembly, wherein the middle frame assembly is arranged on one side, deviating from the display side, of the flexible display module 50, and the middle frame assembly can support and fix the flexible display module 50. The display device may further include a rear cover disposed on a side of the middle frame assembly facing away from the flexible display module 50.

As shown in fig. 1 to 5, the flexible display module 50 may include two bending regions, namely a first bending region 501 and a second bending region 502, and the flexible display module 50 may be folded outwards through the first bending region 501 and folded inwards (towards the display side) through the second bending region 502. The middle frame assembly may include a first frame 10, a second frame 20 rotatably connected to one end of the first frame 10, and a third frame 30 rotatably connected to the other end of the first frame 10, where the second frame 20 rotates relative to the first frame 10 to enable the flexible display module 50 to fold outwards through the first bending region 501, and the third frame 30 rotates relative to the first frame 10 to enable the flexible display module 50 to fold inwards through the second bending region 502. The second frame 20 and the third frame 30 can each be independently unfolded and folded. In the display device of fig. 1, the second frame 20 and the third frame 30 are both in a folded state, in the display device of fig. 2, the second frame 20 and the third frame 30 are both in a flattened state, fig. 3 is a schematic front view structure of the display device when the second frame 20 and the third frame 30 are both in a folded state, fig. 4 is a schematic front view structure of the display device when the second frame 20 is in a folded state and the third frame 30 is in a flattened state, and fig. 5 is a schematic rear view structure of the display device when the second frame 20 is in a folded state and the third frame 30 is in a flattened state. The lengths of the first frame 10 and the third frame 30 may be substantially the same, and the length of the second frame 20 may be less than the length of the first frame 10, for example, the length of the second frame 20 may be less than half the length of the first frame 10. The rear cover may include a first cover provided on the first frame 10, a second cover provided on the second frame 20, and a third cover provided on the third frame 30. The display device of this embodiment is in under the complete folding state, and the majority of flexible display module assembly 50 is in the infolding state, can protect the screen better, and the partly of flexible display module assembly 50 is in the infolding state and can show, can carry out man-machine interaction better like this, improves user experience.

Some foldable display devices, the length dimension of the middle frame component is unchanged, the flexible display module of the display device generates a certain slippage (the end edge of the flexible display module is displaced in the direction perpendicular to the bending axis in a folded state compared with the flattened state) when the display device is folded (inwards folded or outwards folded), the length dimension of the middle frame component is larger in order to enable the flexible display module to be located in the frame of the middle frame component in the folded state and the flattened state, and the frame dimension of the display device is larger in order to cover the slippage of the flexible display module, so that the narrow frame design cannot be realized. As shown in fig. 6 and 7, fig. 6 is a schematic structural diagram of the display device in fig. 1 in a flattened state in some technologies, fig. 7 is a schematic front view of the display device in fig. 6 in a folded state, in the display device in fig. 6, the second frame 20 and the third frame 30 are both in a flattened state, the surfaces of the flexible display module 50 facing away from the display side may be fixed on the first frame 10 and the third frame 30 and may not be fixed with the second frame 20, and the end edge 51 of the flexible display module 50 is closer to the end edge of the second frame 20; in the display device of fig. 7, the second frame 20 and the third frame 30 are both in a folded state, the second frame 20 rotates to realize the outward folding of the flexible display module 50, and the third frame 30 rotates to realize the inward folding of the flexible display module 50, because the surface of the flexible display module 50 facing away from the display side is not fixed with the second frame 20, the end edge 51 of the flexible display module 50 is gradually far away from the end edge of the second frame 20 in the outward folding process of the first bending region 501 of the flexible display module 50, which can be understood as the tendency that the flexible display module 50 contracts in the direction close to the first frame 10, the distance between the end edge 51 of the flexible display module 50 and the end edge of the second frame 20 is the largest at the end of the outward folding process, i.e., the flexible display module 50 generates a certain slippage in the outward folding process (the slippage is about equal to half of the circumference of the rotation axis between the first frame 10 and the second frame 20 in some examples), and the size of the second frame 20 in fig. 6 cannot be changed, so that the size of the flexible display module 50 can be positioned in the folded state and the frame 50 can be designed to be narrower, and the size of the frame assembly cannot be designed to be narrower.

The embodiment of the disclosure provides a display device, which comprises a flexible display module and a middle frame assembly arranged on one side, deviating from a display side, of the flexible display module. As shown in fig. 8 to 10, fig. 8 is a schematic structural view of a middle frame assembly of a display device according to some exemplary embodiments in a flattened state, fig. 9 is a schematic partial structural view of the middle frame assembly of fig. 8, and fig. 10 is a schematic partial structural view of the middle frame assembly of fig. 8 in a folded state, the middle frame assembly including a first frame 10, a second frame 20, and a transmission assembly connected between the first frame 10 and the second frame 20; the transmission assembly is arranged such that the second frame 20 is rotatable relative to the first frame 10 to switch between a first folded state and a first flattened state; the transmission assembly is further arranged to move the second frame 20 in a direction approaching the first frame 10 during rotation of the second frame 20 in a first direction (illustratively clockwise, shown by the arrow-headed arc in fig. 9) to the first folded state. The surface of the flexible display module facing away from the display side is fixed on the first frame 10 and the second frame 20.

According to the display device disclosed by the embodiment of the disclosure, the second frame body 20 of the middle frame assembly can move towards the direction close to the first frame body 10 in the process of rotating to the folding state, so that the display device disclosed by the embodiment of the disclosure can reduce the size of the middle frame assembly in the process of folding outwards (bending towards one side deviating from the display side) through the second frame body 20, and can not pull the flexible display module in the process of folding outwards, and compared with the design scheme that the length size of the middle frame assembly of some foldable display devices is fixed, the display device disclosed by the embodiment of the disclosure can reduce the frame size of the display device.

In some exemplary embodiments, as shown in fig. 8 to 10, the transmission assembly is further configured to drive the second frame 20 to move away from the first frame 10 during rotation of the second frame 20 in a direction opposite to the first direction (illustratively, counterclockwise) to the first flattened state. Thus, an external force is not generated on the flexible display module 50 in the flattening process of the second frame body 20, so that the display device is ensured not to generate additional acting force on the flexible display module 50 in the folding process and the flattening process, and the display effect of the flexible display module 50 is ensured.

In some exemplary embodiments, as shown in fig. 8 to 10, the transmission assembly may include a rotation shaft 41 rotatably provided on the first frame 10, a slider 42 connected to the rotation shaft 41, and a connection member 43 connected between the first frame 10 and the second frame 20; the sliding piece 42 is provided with a sliding groove, the second frame 20 is provided with a sliding part, and the sliding part is slidably arranged in the sliding groove and can slide along the sliding groove in the rotation process of the second frame 20; the connecting piece 43 is configured to be capable of being attached to the rotating shaft 41 to bend during rotation of the second frame 20 in a first direction, and to pull the second frame 20 to move along the sliding chute in a direction approaching the first frame 10, and is configured to be capable of being flattened and pushing the second frame 20 to move along the sliding chute in a direction away from the first frame 10 during rotation of the second frame 20 in a direction opposite to the first direction.

In one example of the present embodiment, as shown in fig. 8 and 9, the rotation shaft 41 may be rotatably disposed at one end of the first frame 10, and two ends of the rotation shaft 41 may protrude from corresponding sides of the first frame 10. Illustratively, the first frame 10 may include a first frame and a second frame disposed opposite and parallel to each other, and a fixing plate connected between the first frame and the second frame, wherein one ends of the first frame and the second frame, which are close to the second frame 20, protrude from the fixing plate, and the protruding portions of the first frame and the second frame are provided with a shaft hole. The two ends of the rotating shaft 41 may be respectively provided with a journal, and the journals at the two ends of the rotating shaft 41 are respectively rotatably disposed in the two shaft holes and may extend out of the two shaft holes. The diameter of the rotation shaft 41 may be smaller than the thickness of the first frame 10.

In an example of the present embodiment, as shown in fig. 8 to 11, fig. 11 is a schematic view of a partial explosion structure of the middle frame assembly of fig. 9, the sliding member 42 may include a first sliding member 421 and a second sliding member 422, the first sliding member 421 is fixedly connected to one end of the rotating shaft 41, and the second sliding member 422 is fixedly connected to the other end of the rotating shaft 41; the sliding part may include a first sliding part slidably engaged with the first sliding part 421 and a second sliding part 221 slidably engaged with the second sliding part 422 (shown in fig. 11). For example, the first sliding member 421 may have a plate structure, one end of the first sliding member 421 may be provided with a first fixing hole, a journal of one end of the rotating shaft 41 may be connected with the first fixing hole in an interference fit manner, a side of the first sliding member 421 facing the second frame 20 may be provided with a first sliding groove, and the first sliding portion is slidably disposed in the first sliding groove; the second sliding member 422 may be in a plate structure, one end of the second sliding member 422 may be provided with a second fixing hole 4222, a journal at the other end of the rotating shaft 41 may be connected with the second fixing hole 4222 in an interference fit manner, a side surface of the second sliding member 422 facing the second frame 20 may be provided with a second sliding groove 4221, and the second sliding portion 221 is slidably disposed in the second sliding groove 4221, so that the rotating shaft 41 rotates to drive the first sliding member 421 and the second sliding member 422 to synchronously rotate, so that the second frame 20 rotates smoothly relative to the first frame 10. In this embodiment, when the second frame 20 rotates in the first direction to the first folded state, the distance between the second frame 20 and the rotation shaft 41 (or the first frame 10) may reach a minimum value.

In one example of the present embodiment, as shown in fig. 11, the second frame 20 may have a plate-like structure, and the second frame 20 may include a first side 21 and a second side 22 perpendicular to and opposite to the axial direction of the rotation shaft 41, the first side 21 may be provided with the first sliding portion, and the second side 22 may be provided with the second sliding portion 221. Illustratively, the first sliding portion and the second sliding portion 221 may each include one or more columnar structures, such as a cylinder or an elliptical cylinder structure, an axial direction of which may be parallel to an axial direction of the rotation shaft 41, and the first sliding portion and the second sliding portion 221 may be symmetrically disposed at both sides of the second frame 20. The first sliding portion and the second sliding portion 221 are respectively provided with a plurality of columnar structures, so that the second frame 20 can be prevented from sagging due to dead weight, the first side edge 21 and the first sliding member 421, and the second side edge 22 and the second sliding member 422 are ensured to be in a parallel state all the time, and the first sliding portion and the second sliding portion 221 slide smoothly in the first sliding groove and the second sliding groove 4221 respectively.

In some exemplary embodiments, as shown in fig. 8 and 9, the connecting member 43 may be a chain, a metal sheet, or a strip structure made of other elastic materials. The chain may include a plurality of links, adjacent links being connectable by a chain shaft. The metal sheet has certain elasticity so as to adapt to bending requirements and can be restored to a flattened state, and the material of the metal sheet can be high-elastic steel or liquid metal memory alloy, such as stainless steel, aluminum alloy or titanium alloy, and the like. One end of the connecting member 43 is fixed to the first frame 10, and the other end is fixed to the second frame 20.

In an example of this embodiment, as shown in fig. 11 and 12, fig. 12 is a schematic view of a partial enlarged structure of fig. 11, the first frame 10 may be provided with a first fixing groove 11, the second frame 20 may be provided with a second fixing groove 23, and one end of the connecting member 43 is fixed in the first fixing groove 11, and the other end is fixed in the second fixing groove 23. Illustratively, the first fixing groove 11 may be provided at a side of the fixing plate near the rotation shaft 41, and the second fixing groove 23 may be provided at a side of the second frame 20 near the rotation shaft 41. The two ends of the connecting piece 43 may be provided with fixing posts 431, and the groove walls of the first fixing groove 11 and the second fixing groove 23 may be provided with fixing holes 231 in plug-in fit with the fixing posts 431, so that the two ends of the connecting piece 43 are respectively fixedly connected with the first fixing groove 11 and the second fixing groove 23. The two opposite groove walls of the second fixing groove 23 may also be provided with a limiting groove 232, two sides of the connecting piece 43 fixed at one end of the second fixing groove 23 may also be provided with limiting portions 432, and the two limiting portions 432 may be respectively clamped in the two limiting grooves 232, so as to prevent the connecting piece 43 from shaking.

In one example of the present embodiment, as shown in fig. 8 to 10, the connection member 43 may be one or more (two in the present example); in the first flattened state, the extending direction of the connecting piece 43 is perpendicular to the axial direction of the rotation shaft 41. When the number of the connecting members 43 is plural, the plurality of connecting members 43 may be disposed at intervals and parallel to each other.

In some exemplary embodiments, as shown in fig. 13, a plurality of the connecting members 43 may be provided, two adjacent connecting members 43 may be connected by a supporting layer 44, and the supporting layer 44 may be folded together with the connecting members 43 (for example, may be folded together with the connecting members 43 by being attached to the rotating shaft 41) during the rotation of the second frame 20. Illustratively, the supporting layer 44 may be made of a flexible material, and the supporting layer 44 may be of a unitary structure, or may include a plurality of supporting bars, one end of each supporting bar being connected to one of the adjacent two connecting members 43, and the other end being connected to the other of the adjacent two connecting members 43, and a length direction of each supporting bar may be parallel to an axial direction of the rotating shaft 41. The support layer 44 may be disposed at a gap between the first and second frames 10 and 20, and may be configured to support the flexible display module 50 when the second frame 20 is in the first flattened state. The thickness of the support layer 44 may be the same as the thickness of the connection member 43.

In some exemplary embodiments, as shown in fig. 14, fig. 14 is a schematic partial structural view of a middle frame assembly of some exemplary embodiments, where the transmission assembly may further include a spring 25, where the spring 25 includes a first spring portion (may be a torsion spring) 251 sleeved on the rotation shaft 41, one end of the first spring portion 251 is provided with a first folding leg 2511, the other end is provided with a second folding leg 2512, the first folding leg 2511 is fixed on the first frame 10, and the second folding leg 2512 is fixed on the second frame 20; the first spring part 251 has a torsion force in the first folded state, and the first spring part 251 is in a natural state in the first flattened state. Illustratively, during the process of rotating the second frame 20 in the first direction to the first folded state, the first spring portion 251 may be gradually twisted and generate a torsion force, in the first folded state, the torsion force of the first spring portion 251 may be the greatest, and during the process of rotating the second frame 20 in the opposite direction to the first flattened state, the torsion force of the first spring portion 251 may push the second frame 20 to be quickly rotated to the first flattened state, so as to realize quick deployment.

In one example of the present embodiment, as shown in fig. 14, the spring 25 may further include a second spring portion (may be a compression spring) 252, where a first end of the second spring portion 252 is connected to the second leg 2512; the second spring portion 252 is sleeved on a positioning column 24 provided on the second frame 20, and a second end of the second spring portion 252 abuts against the second frame 20, and an axial direction of the positioning column 24 is perpendicular to an axial direction of the rotating shaft 41; the second spring portion 252 is in a compressed state in the first flattened state. In an exemplary manner, during the process of rotating the second frame 20 in the first direction to the first folded state, the second frame 20 gradually moves towards the direction approaching the first frame 10, the second spring 252 may be gradually compressed, the compression amount of the second spring 252 may be the greatest in the first folded state, during the process of rotating the second frame 20 in the opposite direction to the first flattened state, the second frame 20 gradually moves away from the first frame 10, the elastic force of the second spring 252 may push the second frame 20 to move rapidly away from the first frame 10, and in the first flattened state, the second spring 252 is still in the compressed state, so that the second frame 20 may be tensioned by using the elastic force of the second spring 252 in the first flattened state, which is beneficial to flattening the flexible display module fixed on the middle frame assembly, and reducing the crease.

As shown in fig. 15, for example, fig. 15 is a schematic view of a partial structure of the middle frame assembly of fig. 14 at a spring, a side surface (which may be a surface facing away from the flexible display module) of the second frame 20 may be provided with a groove, the groove may extend to an end of the second frame 20 near the first frame 10, the groove may be provided with the positioning post 24 therein, one end of the positioning post 24 may be fixed on a wall of the groove, and the other end extends toward an end of the second frame 20 near the first frame 10. The second spring portion 252 is sleeved on the positioning post 24, and a second end of the second spring portion 252 abuts against a wall of the groove. The springs 25 may be provided in one or more.

In some exemplary embodiments, as shown in fig. 16 and 17, fig. 16 is a partial schematic structural view of a middle frame assembly of still other exemplary embodiments, and fig. 17 is a partial schematic side view of the middle frame assembly of fig. 16 in a folded-out state, the connection member 43 may be provided as one and in a sheet-like structure, and is provided at a gap between the first frame body 10 and the second frame body 20. One end of the connecting member 43 is fixed to the first frame 10, and the other end is fixed to the second frame 20. Illustratively, the connecting member 43 may be fixed to the first and second frames 10 and 20 by means of glue, screws, rivets, or the like, and in the example of fig. 16, both ends of the connecting member 43 are fixed to the first and second frames 10 and 20 by means of glue and form fixing portions 433. During the rotation of the second frame 20 in the first direction, the connecting piece 43 can be attached to the rotating shaft 41 to bend (as shown in fig. 17), and pull the second frame 20 to move along the chute in a direction approaching to the first frame 10; during the rotation of the second frame 20 in the opposite direction to the first direction, the connecting piece 43 can be flattened (as shown in fig. 16) and push the second frame 20 to move along the chute in a direction away from the first frame 10.

In some exemplary embodiments, as shown in fig. 18, fig. 18 is a schematic cross-sectional structure of a connection member of the middle frame assembly of fig. 16 in some exemplary embodiments, the connection member 43 may include a resilient metal sheet 434, and a first protective layer 435 and a second protective layer 436 disposed on opposite surfaces of the resilient metal sheet 434.

Illustratively, the material of the elastic metal sheet 434 may be stainless steel, aluminum alloy, titanium alloy, liquid metal memory alloy, etc., the material of the first protective layer 435 may be Polyimide (PI) or polyethylene terephthalate (PET), etc., and the material of the second protective layer 436 may be Polyimide (PI) or polyethylene terephthalate (PET), etc. The first protective layer 435 and the second protective layer 436 may be adhered to the elastic metal sheet 434 by an adhesive, and the first protective layer 435 and the second protective layer 436 may provide a tensile force to protect the elastic metal sheet 434 during bending of the connection member 43.

Illustratively, as shown in fig. 19, fig. 19 is a schematic plan view of the resilient metal sheet of fig. 18 in some exemplary embodiments, the resilient metal sheet 434 may have a thickness of 0.02mm to 0.5mm. The elastic metal piece 434 may be provided with a plurality of through holes 4341 to improve bending performance, and the plurality of through holes 4341 may be provided at a middle region of the elastic metal piece 434 in a direction perpendicular to the rotation axis (i.e., in the Y direction in fig. 19). The sizes of the plurality of through holes 4341 may be the same or different, for example, each through hole 4341 may be elongated, the length direction of each through hole 4341 may be parallel to the rotation axis direction (i.e., the X direction in fig. 19), the plurality of through holes 4341 may be arranged in a plurality of rows, the row direction is the direction (X direction) parallel to the rotation axis direction, the plurality of through holes 4341 are arranged in each row, and the through holes 4341 in two adjacent rows may be staggered. The length a of each through hole 4341 may be 3mm to 10mm, the width d of each through hole 4341 may be 0.1mm to 0.6mm, the pitch b of two adjacent through holes 4341 in the row direction may be 0.1mm to 0.6mm, and the distance c between two adjacent rows of through holes 4341 is 0.1mm to 0.6mm. The region (i.e., the open area) of the elastic metal sheet 434 where the plurality of through holes 4341 are provided may include a middle area and transition areas located at both sides of the middle area, and the through holes 4341 of the transition areas may be the same or different in shape and size from the through holes 4341 of the middle area. The width of the middle area is e, the width of the transition areas at two sides is f, and may be set to e=3.14×r, where R is the bending outer diameter of the elastic metal piece 434 when the second frame body is in the first folded state, f=1 mm to 5mm, and the width of the middle area may enable the elastic metal piece 434 to have good bending performance, and the transition areas at two sides may play a role in transition, so that the strength of the elastic metal piece 434 gradually transits from the open area to the non-open area, and the edge stress concentration of the elastic metal piece 434 is prevented.

In some exemplary embodiments, as shown in fig. 20, fig. 20 is a schematic cross-sectional structure of a connector of the middle frame assembly of fig. 16 in other exemplary embodiments, the connector 43 may include a plurality of elastic metal sheets 434 stacked, and two adjacent elastic metal sheets 434 are adhered by an adhesive layer 437. In the example of fig. 20, the elastic metal pieces 434 are provided in three, and in other embodiments, the elastic metal pieces 434 may be provided in two or more. The elastic metal piece 434 may be made of stainless steel, aluminum alloy, titanium alloy or liquid metal memory alloy, and the adhesive layer 437 may be made of a material with low elastic modulus, and has good elastic deformability, such as Optically Clear Adhesive (OCA). The connecting member 43 of this example is stacked with a plurality of elastic metal sheets 434, and can have good elasticity and strength.

In some exemplary embodiments, as shown in fig. 21, fig. 21 is a schematic partial structure of a middle frame assembly of still other exemplary embodiments, the transmission assembly may further include a spring 26, the spring 26 may be disposed in the sliding groove of the sliding member 42, the spring 26 may be elastically deformed by being pressed by the sliding portion during rotation of the second frame 20 in the first direction, and the spring 26 may push the sliding portion to slide along the sliding groove by using its own elastic force during rotation of the second frame 20 in the opposite direction to the first direction. Thus, by providing the spring 26, the second frame 20 can be quickly switched from the first folded state to the first flattened state, and quick flattening can be achieved.

In some exemplary embodiments, as shown in fig. 21, the slider 42 may include a first slider 421 and a second slider 422, and the slider may include a first slider portion slidably engaged with a first sliding groove of the first slider 421 and a second slider portion slidably engaged with a second sliding groove of the second slider 422. The first sliding member 421 and the second sliding member 422, and the first sliding portion and the second sliding portion may be disposed in the same manner as in the previous embodiment. The springs may be disposed in both the first chute and the second chute.

In an example of the present embodiment, taking the second slider 422 as an example, the spring 26 may be disposed in the second chute of the second slider 422, and the spring 26 is elastically deformed by being pressed by the second sliding portion during the rotation of the second frame 20 in the first direction, and pushes the second sliding portion to slide along the second chute by its own elastic force during the rotation of the second frame 20 in the opposite direction to the first direction. For example, the spring 26 may be a compression spring, and one end of the spring 26 may be fixed to an end of the second sliding groove of the second sliding member 422 near the first frame 10. In the first flattened state, the spring 26 may have an elastic force, and the other end of the spring 26 may abut against the second sliding portion, and may abut against an end of the second chute, which is far from the first frame 10.

In some exemplary embodiments, an end of the sliding groove of the sliding member, which is far away from the first frame body, may be provided with a clamping groove, the sliding portion may slide into the clamping groove when the second frame body rotates to the first flattened state in the opposite direction of the first direction, and the sliding portion may slide out of the clamping groove and slide along the sliding groove when the second frame body rotates from the first flattened state in the first direction. Therefore, in the first flattening state, the sliding part is matched with the clamping groove, so that the locking rotating shaft can be realized, the whole flexible display module of the foldable display device with the middle frame assembly is in a flattening state, and stamping is reduced.

Taking the second sliding member as an example, as shown in fig. 22 and 23, fig. 22 is a schematic structural view of the second sliding member of the middle frame assembly of fig. 21 in some exemplary embodiments, fig. 23 is a schematic front view of the second sliding member of fig. 22, the second sliding member 422 may be in a plate structure, one end of the second sliding member 422 may be provided with a second fixing hole 4222 in interference fit connection with an end of the rotating shaft 41, a side of the second sliding member 422 facing the second frame 20 is provided with a second sliding groove 4221, the second sliding portion is slidably disposed in the second sliding groove 4221, and an end of the second sliding groove 4221 away from the first frame may be provided with a second clamping groove 4223. The second sliding portion may slide into the second locking groove 4223 when the second frame 20 rotates in the opposite direction to the first flattened state, and may slide out of the second locking groove 4223 and along the second sliding groove 4221 when the second frame 20 rotates in the first direction from the first flattened state. Illustratively, the second clamping groove 4223 may be a concave groove with an arc surface shape, the second sliding portion may be a cylindrical protrusion, and an end surface of the cylindrical protrusion matched with the second clamping groove 4223 may be an arc surface structure so as to be beneficial to being matched with the second clamping groove 4223. Similarly, a first clamping groove can be formed in the first sliding groove of the first sliding piece.

In some exemplary embodiments, as shown in fig. 24, fig. 24 is a partial structural schematic diagram of a middle frame assembly of other exemplary embodiments, the middle frame assembly including a first frame 10, a second frame 20, and a transmission assembly connected between the first frame 10 and the second frame 20.

The transmission assembly may include a rotation shaft 41 rotatably provided on the first frame 10, a slider 42 connected to the rotation shaft 41, and a rack and pinion mechanism; the sliding piece 42 is provided with a sliding groove, the second frame 20 is provided with a sliding part, and the sliding part is slidably arranged in the sliding groove and can slide along the sliding groove in the rotation process of the second frame 20; the rack and pinion mechanism is configured to drive the second frame 20 to move along the chute in a direction approaching the first frame 10 during rotation of the second frame 20 in a first direction (illustratively, clockwise) to the first folded state, and is configured to drive the second frame 20 to move along the chute in a direction away from the first frame 10 during rotation of the second frame 20 in a direction opposite to the first direction (illustratively, counterclockwise) to the first flattened state.

In this embodiment, the rotation shaft 41 and the slider 42 may be disposed in the same manner as in the embodiment of fig. 8 to 10.

In some exemplary embodiments, the rack and pinion mechanism may include a first gear provided on the rotation shaft, a second gear provided on the slider, a belt provided on the first gear and the second gear, and a rack provided on the second frame and engaged with the second gear. In this way, in the process of rotating the second frame body along the first direction, the rotating shaft and the first gear can be driven to synchronously rotate by the sliding piece, the first gear drives the second gear to rotate by the driving belt, and the second gear can drive the second frame body to move towards the direction close to the first frame body by being meshed with the rack; in the process of rotating the second frame body in the opposite direction of the first direction, the second gear can drive the second frame body to move in the direction away from the first frame body through being meshed with the rack. In other examples, one or more gear trains may be provided between the second gear and the rack.

In other exemplary embodiments, as shown in fig. 24, the rack and pinion mechanism may include a first gear 61 provided on the rotation shaft 41, a second gear 62 provided on the slider 42, a belt 65 fitted over the first gear 61 and the second gear 62, a third gear 63 coaxially provided with the second gear 62, and a rack gear 64 provided on the second frame 20 and engaged with the third gear 63.

Illustratively, the sliding member 42 may include a first sliding member 421 and a second sliding member 422, wherein the first sliding member 421 is fixedly connected to one end of the rotating shaft 41, and the second sliding member 422 is fixedly connected to the other end of the rotating shaft 41; the sliding part includes a first sliding part slidably engaged with the first sliding part 421 and a second sliding part slidably engaged with the second sliding part 422. The second frame 20 may include a first side 21 and a second side 22 perpendicular to and opposite to the axial direction of the rotation shaft 41, the first side 21 may be provided with the first sliding portion, and the second side 22 may be provided with the second sliding portion.

Illustratively, the rack and pinion mechanisms may be provided in two, and two rack and pinion mechanisms may be provided at both end positions of the rotation shaft 41, respectively. Taking the rack and pinion mechanism at one end of the rotating shaft 41 where the first sliding member 421 is located as an example, one end of the first sliding member 421 and the first gear 61 are both fixed at the first end of the rotating shaft 41, the first sliding member 421 and the first gear 61 are both located outside the first frame 10, the first gear 61 may be disposed on one side of the first sliding member 421 away from the first frame 10, and the first sliding member 421, the first gear 61 and the rotating shaft 41 may rotate synchronously. The second gear 62 and the third gear 63 are coaxially connected through a connecting shaft, the connecting shaft is rotationally arranged at the other end of the first sliding member 421, the second gear 62 is located at one side, far away from the second frame body 20, of the first sliding member 421, the third gear 63 is located at the first side face of the second frame body 20, a rack 64 is arranged on the first side face of the second frame body 20, the rack 64 is meshed with the third gear 63, a frame of the first side edge 21 of the second frame body 20 can be provided with an avoidance groove, the connecting shaft can be located in the avoidance groove, and the avoidance groove is formed in the way that the connecting shaft can be avoided in the sliding process of the second frame body 20 along the first sliding member 421. The first side 21 of the second frame 20 is provided with a first sliding portion, and the first sliding portion is slidably disposed in the chute of the first slider 421. The first gear 61 and the second gear 62 are driven by a belt. In this way, in the process of rotating the second frame 20 along the first direction, the sliding member 42 may drive the rotation shaft 41 and the first gear 61 to rotate synchronously, the first gear 61 drives the second gear 62 to rotate through the driving belt 65, the second gear 62 drives the third gear 63 to rotate synchronously, and the third gear 63, by meshing with the rack 64, may drive the second frame 20 to move in a direction approaching to the first frame 10; during the rotation of the second frame 20 in the opposite direction of the first direction, the third gear 63, by engaging with the rack 64, can drive the second frame 20 to move in a direction away from the first frame 10.

In some exemplary embodiments, the first frame may have a first magnetic member thereon, and the second frame may have a second magnetic member thereon; in the first folded state, the first frame body and the second frame body are locked through magnetic attraction between the first magnetic piece and the second magnetic piece. In this way, the first frame and the second frame can be secured in the first folded state. For example, the first magnetic member may be disposed on a side of the first frame, and the second magnetic member may be disposed on a side of the second frame, the first magnetic member corresponding to the second magnetic member in position in the first folded state.

In some exemplary embodiments, as shown in fig. 1 to 5, the middle frame assembly may further include a third frame 30 rotatably connected to an end of the first frame 10 remote from the second frame 20, and switchable between a second folded state and a second flattened state; the surface of the flexible display module 50 facing away from the display side may also be fixed to the third frame 30.

In one example of the present embodiment, as shown in fig. 1 to 5, the third frame 30 is provided to be rotatable in the first direction (illustratively, clockwise) to the second folded state with respect to the first frame 10, and to be rotatable in the opposite direction (illustratively, counterclockwise) to the first direction to the second flattened state. Illustratively, when the second frame 20 rotates in the first direction to the first folded state relative to the first frame 10, the flexible display module 50 can be folded outwards through the first bending region 501, and when the third frame 30 rotates in the first direction to the second folded state relative to the first frame 10, the flexible display module 50 can be folded inwards through the second bending region 502. In the display device of this example, the first bending region 501 of the flexible display module 50 may be folded outwards, and the second bending region 502 may be folded inwards, that is, the display device of this example may be folded in an S-shape. In this example, the lengths of the first frame 10 and the third frame 30 may be substantially the same, and the length of the second frame 20 may be less than the length of the first frame 10, such as the length of the second frame 20 may be less than half the length of the first frame 10. In other embodiments, the lengths of the first, second, and third frames may be substantially the same.

In some exemplary embodiments, the middle frame assembly may further include a fourth frame rotatably coupled to an end of the second frame remote from the first frame and switchable between a third folded state and a third flattened state. The fourth frame may be provided rotatably in the third folded state in a direction opposite to the first direction (illustratively, counterclockwise) with respect to the second frame, and rotatably in the first direction (illustratively, clockwise) to the third flattened state. Correspondingly, the flexible display module assembly further comprises a third bending area, and when the fourth frame body rotates to the third folding state along the opposite direction of the first direction relative to the second frame body, the flexible display module assembly can be folded inwards through the third bending area. In the display device of this example, the first bending region of the flexible display module may be folded outwards, and the second bending region and the third bending region may be folded inwards, i.e. the display device of this example may be folded in a W shape.

In some exemplary embodiments, the flexible display module may include a display panel, a polarizer and a cover plate sequentially stacked on a display side of the display panel, a back film attached on a surface of the display panel facing away from the display side, a support layer provided on a side of the back film facing away from the display panel, and a circuit board bonded to the display panel. The cover plate and the polaroid can be bonded by a first bonding layer, the polaroid and the display panel can be bonded by a second bonding layer, and the first bonding layer and the second bonding layer can be Optically Clear Adhesive (OCA). In other embodiments, the polarizer may be omitted, and an anti-reflection layer may be provided on the display panel instead of the polarizer. The circuit board may be a flexible circuit board (FPC) and may be located at a side of the display panel facing away from the display side (the FPC may be bent to a side of the display panel facing away from the display side, or the binding area of the display panel may be bent to a side of the display panel facing away from the display side), and the circuit board may be further configured to be connected with an external circuit to provide a driving signal to the display panel.

Illustratively, the supporting layer may include a metal layer, and the metal layer may be made of stainless steel or copper, for example, the metal layer may be made of stainless steel with a thickness ranging from 0.03mm to 0.05mm, the stainless steel with a thickness ranging from thinner to better flexibility, and a portion of the metal layer corresponding to the bending region of the flexible display module may not be provided with an opening; alternatively, the metal layer may be stainless steel with a thickness greater than 0.05mm (for example, a thickness of 0.15 mm), and the stainless steel with a thickness range is thicker, and in order to improve bending performance, a portion of the metal layer corresponding to the bending region of the flexible display module may be provided with a plurality of openings. The supporting layer may further include a buffer layer disposed at a side of the supporting layer facing the display panel to improve a buffer performance, and the buffer layer may include any one or more of a foam layer, a polyethylene terephthalate (PET) layer, and a Polyimide (PI) layer. Alternatively, the supporting layer may include any one or more of a glass fiber composite material and a carbon fiber composite material (such as carbon fiber reinforced plastic, CFRP), for example, may include a carbon fiber composite material, and the carbon fiber composite material may have a three-layer structure, and the total thickness may be about 30um to 300um, the thickness of the middle layer may be 100um to 150um, and the thickness of the upper layer and the lower layer may be 20um to 50um; the part of the supporting layer corresponding to the bending area of the flexible display module can be provided with a plurality of openings, so that bending performance can be improved.

Illustratively, the material of the cover plate may include one or more plastics such as Polyimide (PI), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyvinylidene chloride, polyvinylidene fluoride (PVDF), polystyrene, ethylene vinyl alcohol copolymer, polyethersulfone (PES), polyetherimide (PEI), polyphenylene sulfide (PPS), polyacrylate, triacetyl cellulose (TAC), cellulose Acetate Propionate (CAP), and the like. The cover plate can be made of glass, the thickness of the thin glass can be 10-200 um, such as ultrathin glass (UTG) with the thickness of 10-50 um (30 um), and the cover plate made of the thin glass can simultaneously meet the flexible folding property, the optical property and the impact resistance. To increase the performance of the cover plate, such as impact resistance, ball drop test performance, etc., the cover plate may be a one-layer structure or a multi-layer laminate structure, for example, the cover plate may be any one of a single CPI (transparent polyimide) layer, two CPI layers, CPI/PET laminate, PET/UTG laminate, PET/UTG/PET laminate.

The display panel may be a flexible Organic Light Emitting Diode (OLED) display panel, and the display panel may include a driving structure layer, a light emitting structure layer, a packaging structure layer, and a touch structure layer sequentially stacked on a flexible substrate. The material of the flexible substrate may include any one or more of polystyrene, polyvinyl alcohol, polymethyl methacrylate, polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose triacetate, and cellulose acetate propionate. The material of the flexible substrate may include a glass fiber composite material, a carbon fiber composite material, or the like. The driving structure layer includes a plurality of pixel driving circuits, and the pixel driving circuits may include a plurality of thin film transistors (T) and storage capacitors (C), and may have a structure of 3T1C, 4T1C, 5T2C, 6T1C, or 7T 1C. The light emitting structure layer may include a plurality of OLED light emitting devices, and illustratively, the light emitting structure layer may include a first electrode layer, a pixel defining layer, a light emitting function layer, and a second electrode layer, the first electrode layer includes a plurality of first electrodes disposed on the driving structure layer, each first electrode is connected with one of the pixel driving circuits, the pixel defining layer is disposed on a side of the plurality of first electrodes away from the substrate and is provided with a plurality of pixel openings, each pixel opening exposes a surface of a corresponding one of the first electrodes away from the substrate, the light emitting function layer and the second electrode layer are sequentially stacked on a side of the plurality of first electrodes and the pixel defining layer away from the substrate, and each first electrode, the light emitting function layer, and the second electrode layer are sequentially stacked and form one OLED light emitting device. The packaging structure layer can comprise a first inorganic packaging layer, an organic packaging layer and a second inorganic packaging layer which are sequentially stacked, the materials of the first inorganic packaging layer and the second inorganic packaging layer can comprise one or more of silicon nitride, silicon oxide and silicon oxynitride, and the materials of the organic packaging layer can comprise organic resin. The touch control structure layer can adopt a mutual capacitance type structure or a self-capacitance type structure and can be directly formed on the surface, far away from the substrate, of the packaging structure layer; the mutual capacitance structure comprises a driving (Tx) electrode and an induction (Rx) electrode, and the touch control structure layer can comprise two metal layers; the self-contained structure can adopt a single-layer metal to form the touch electrode.

The display device of the embodiment of the disclosure may be: any product or component with display function such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like.

In the drawings, the size of constituent elements, thicknesses of layers, or regions may be exaggerated for clarity. Accordingly, embodiments of the present disclosure are not necessarily limited to this dimension, and the shape and size of each component in the drawings do not reflect the true scale. Furthermore, the figures schematically illustrate some examples, and embodiments of the present disclosure are not limited to the shapes or values illustrated in the figures.

In the description herein, "parallel" refers to a state in which two straight lines form an angle of-10 ° or more and 10 ° or less, and thus includes a state in which the angle is-5 ° or more and 5 ° or less. The term "perpendicular" refers to a state in which the angle formed by two straight lines is 80 ° or more and 100 ° or less, and thus includes a state in which the angle is 85 ° or more and 95 ° or less.

In the description herein, the positional or positional relationship indicated by the terms "upper", "lower", "left", "right", "top", "inner", "outer", "axial", "four corners", and the like are based on the positional or positional relationship shown in the drawings, and are merely for convenience in describing the embodiments of the present disclosure, and are not indicative or implying that the structure referred to has a specific orientation, is configured and operated in a specific orientation, and thus is not to be construed as limiting the present disclosure.

In the description herein, unless explicitly stated and limited otherwise, the terms "connected," "fixedly connected," "mounted," "assembled" and "mounted" are to be construed broadly, and may be, for example, fixedly connected, or detachably connected, or integrally connected; the terms "mounted," "connected," "fixedly connected," and "coupled" may be directly connected, indirectly connected through intervening media, or in communication between two elements. The meaning of the above terms in the embodiments of the present disclosure may be understood by those of ordinary skill in the art as appropriate.

Claims

1. A display device, characterized in that: the display device comprises a flexible display module and a middle frame assembly arranged on one side of the flexible display module, which is away from a display side;

the middle frame assembly comprises a first frame body, a second frame body and a transmission assembly connected between the first frame body and the second frame body;

the transmission assembly is arranged such that the second frame body can rotate relative to the first frame body to switch between a first folded state and a first flattened state;

the transmission assembly is further arranged to drive the second frame to move in a direction approaching to the first frame in the process that the second frame rotates to the first folding state along the first direction;

The transmission assembly is further arranged to drive the second frame to move in a direction away from the first frame in the process that the second frame rotates in the opposite direction of the first direction to the first flattening state;

the transmission assembly comprises a rotating shaft rotatably arranged on the first frame body and a sliding piece connected with the rotating shaft; the sliding piece is provided with a sliding groove, the second frame body is provided with a sliding part, and the sliding part is arranged in the sliding groove in a sliding manner and slides along the sliding groove in the rotating process of the second frame body;

the transmission assembly further comprises a connecting piece connected between the first frame body and the second frame body; the connecting piece is arranged to be capable of being stuck to the rotating shaft for bending in the process of rotating the second frame body along the first direction, pulls the second frame body to move along the sliding groove in the direction close to the first frame body, and is arranged to be capable of being flattened and pushing the second frame body to move along the sliding groove in the direction far away from the first frame body in the process of rotating the second frame body along the opposite direction of the first direction;

the surface of the flexible display module set, which is far away from the display side, is fixed on the first frame body and the second frame body.

2. The display device according to claim 1, wherein: the sliding piece comprises a first sliding piece and a second sliding piece, the first sliding piece is fixedly connected with one end of the rotating shaft, and the second sliding piece is fixedly connected with the other end of the rotating shaft;

3. The display device according to claim 2, wherein: the second frame body comprises a first side edge and a second side edge which are perpendicular to the axial direction of the rotating shaft and are opposite to each other, the first side edge is provided with the first sliding part, and the second side edge is provided with the second sliding part.

4. The display device according to claim 1, wherein: the connecting piece is a chain or a metal sheet, one end of the connecting piece is fixed on the first frame body, and the other end of the connecting piece is fixed on the second frame body.

5. The display device according to claim 4, wherein: the first frame body is provided with a first fixing groove, the second frame body is provided with a second fixing groove, one end of the connecting piece is fixed in the first fixing groove, and the other end of the connecting piece is fixed in the second fixing groove.

6. The display device according to claim 4, wherein: the number of the connecting pieces is one or more; in the first flattened state, the extending direction of the connecting member is perpendicular to the axial direction of the rotating shaft.

7. The display device according to claim 6, wherein: the connecting pieces are multiple, two adjacent connecting pieces are connected through the supporting layer, and the supporting layer can be bent together with the connecting pieces in the rotation process of the second frame body.

8. The display device according to claim 1, wherein: the connecting piece comprises an elastic metal sheet, and a first protective layer and a second protective layer which are arranged on two opposite surfaces of the elastic metal sheet; one end of the connecting piece is fixed on the first frame body, and the other end of the connecting piece is fixed on the second frame body.

9. The display device according to claim 8, wherein: the elastic metal sheet is made of stainless steel, aluminum alloy, titanium alloy or liquid metal memory alloy, the first protective layer is made of polyimide or polyethylene terephthalate, and the second protective layer is made of polyimide or polyethylene terephthalate.

10. The display device according to claim 1, wherein: the connecting piece comprises a plurality of overlapped elastic metal sheets, and two adjacent elastic metal sheets are bonded through an adhesive layer; one end of the connecting piece is fixed on the first frame body, and the other end of the connecting piece is fixed on the second frame body.

11. The display device according to claim 1, wherein: the transmission assembly further comprises a spring, the spring is arranged in the sliding groove, the spring is extruded by the sliding part to elastically deform in the process of rotating the second frame body along the first direction, and the spring pushes the sliding part to slide along the sliding groove by utilizing self elasticity in the process of rotating the second frame body along the opposite direction of the first direction.

12. The display device according to claim 1, wherein: the transmission assembly further comprises a spring, the spring comprises a first spring part sleeved on the rotating shaft, a first folding leg is arranged at one end of the first spring part, a second folding leg is arranged at the other end of the first spring part, the first folding leg is fixed on the first frame body, and the second folding leg is fixed on the second frame body;

13. The display device according to claim 12, wherein: the spring further comprises a second spring part, and the first end of the second spring part is connected with the second folding leg;

14. The display device according to claim 1, wherein: one end of the sliding groove, which is far away from the first frame body, is provided with a clamping groove, the sliding part can slide into the clamping groove when the second frame body rotates to a first flattening state along the reverse direction of the first direction, and the sliding part can slide out of the clamping groove and slide along the sliding groove in the rotating process of the second frame body from the first flattening state along the first direction.

15. A display device as claimed in any one of claims 1 to 3, characterized in that: the transmission assembly further comprises a first gear arranged on the rotating shaft, a second gear arranged on the sliding piece, a transmission belt sleeved on the first gear and the second gear, and a rack arranged on the second frame body and meshed with the second gear.

16. A display device as claimed in any one of claims 1 to 3, characterized in that: the transmission assembly further comprises a first gear arranged on the rotating shaft, a second gear arranged on the sliding piece, a transmission belt sleeved on the first gear and the second gear, a third gear coaxially arranged with the second gear, and a rack arranged on the second frame body and meshed with the third gear.

17. A display device as claimed in any one of claims 1 to 3, characterized in that: the first frame body is provided with a first magnetic piece, and the second frame body is provided with a second magnetic piece;

18. A display device as claimed in any one of claims 1 to 3, characterized in that: the middle frame assembly further comprises a third frame body which is rotatably connected to one end, far away from the second frame body, of the first frame body and can be switched between a second folded state and a second flattened state; the surface of the flexible display module set, which is far away from the display side, is also fixed on the third frame body.

19. The display device of claim 18, wherein: the third frame is configured to be rotatable relative to the first frame in the first direction to the second folded state and rotatable in a direction opposite to the first direction to the second flattened state.