CN210799707U

CN210799707U - Hinge mechanism, folding display device and communication equipment

Info

Publication number: CN210799707U
Application number: CN201920905678.2U
Authority: CN
Inventors: 陈小硕; 刘明生; 陆苏; 刘建军; 陈进; 刘昌白
Original assignee: Shenzhen Everwin Precision Technology Co Ltd
Current assignee: Shenzhen Everwin Precision Technology Co Ltd
Priority date: 2019-06-14
Filing date: 2019-06-14
Publication date: 2020-06-19
Anticipated expiration: 2029-06-14

Abstract

A hinge mechanism comprises a first folding plate, a second folding plate, a back cover, a sliding block, a transmission rod and a transmission assembly, wherein the sliding block is respectively limited on the first folding plate and the second folding plate in a sliding mode, the transmission rod is rotatably hinged with one end of the sliding block, the transmission assembly is fixedly hinged with the transmission rod and comprises a pair of first shaft bodies, at least one pair of second shaft bodies arranged between the first shaft bodies, at least four gears which are sleeved on the first shaft bodies and the second shaft bodies and are meshed with each other, and a first clamping plate and a second clamping plate which are sleeved on the first shaft bodies and the second shaft bodies and are positioned at two ends of the four gears; the application also provides a folding display device and communication equipment.

Description

Hinge mechanism, folding display device and communication equipment

Technical Field

The present disclosure relates to the field of communications electronics, and more particularly, to a hinge mechanism, a foldable display device and a communication apparatus.

Background

With the development of the folding screen technology, the folding screen mobile phone has become a hot spot technology. Although the folding screen can be bent, the 180-degree bending cannot be realized, and the bent part still needs to keep a certain R angle, otherwise the screen can be damaged. The existing folding mode is divided into inward folding and outward folding, namely the screen is positioned at the inner side or the outer side after being folded, for example, Mate X issued by Huawei is outward folding, but the outward folding has the problems that the screen is in an exposed state and is easily scratched by a hard object, and the folding screen is fragile.

At present, each mobile phone manufacturer applies for a folding mechanism, but most of the mobile phone manufacturers have complex structures and too many components, and the R angle folding of the folding screen is realized through a folding plate and a complex hinge mechanism, so that the folding screen is protected from being damaged. However, the complexity of the mechanism and assembly causes instability in folding and is prone to error.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is desirable to provide a hinge mechanism, a foldable display device and a communication apparatus, wherein the hinge mechanism can enable the foldable display device to be folded uniformly to protect a relatively fragile foldable screen, and the hinge mechanism has a simple structure and good stability.

In order to solve the above technical problems, the present application provides a hinge mechanism, which comprises a first folding plate, a second folding plate, a back cover, a sliding block respectively sliding and limited on the first folding plate and the second folding plate, a transmission rod rotatably hinged with one end of the sliding block, and a transmission assembly fixedly hinged with the transmission rod, the transmission assembly comprises a pair of first shaft bodies, at least a pair of second shaft bodies arranged between the first shaft bodies, at least four gears which are sleeved on the first shaft bodies and the second shaft bodies and are mutually meshed, and a first clamping plate and a second clamping plate which are sleeved on the first shaft bodies and the second shaft bodies and are positioned at two ends of the four gears, the transmission rod is fixedly hinged with two first shaft bodies positioned at the outer side, the first shaft bodies are fixed with gears on the first shaft bodies and can not rotate, the second shaft body and the gear on the second shaft body can rotate relatively, and two ends of the first shaft body and the second shaft body are fixed on the back cover.

Preferably, a plurality of shaft holes with the circle centers positioned on the same straight line are correspondingly arranged on the first clamping plate and the second clamping plate, the first shaft body and the second shaft body are sleeved in the shaft holes, the second shaft body is arranged between the two first shaft bodies side by side, the second shaft body comprises four or six or eight, and each second shaft body is provided with a gear which is meshed with each other.

Preferably, the transmission assembly further comprises a third clamping plate and a spring clamped between the second clamping plate and the second clamping plate, the spring is sleeved outside the first shaft body, the spring provides elastic force to the second clamping plate and transmits the elastic force to the gear, the gear is prevented from being clamped by the first clamping plate and the second clamping plate and cannot rotate, and the second clamping plate is not fixed to the first shaft body and the second shaft body.

Preferably, the first folding plate and the second folding plate are provided with sliding groove mechanisms corresponding to the sliding blocks, each sliding groove mechanism comprises two convex blocks arranged in parallel, a sliding groove arranged between the two convex blocks and a limiting groove arranged at the bottom of one side of the sliding groove on the convex block, and the sliding blocks are limited in the sliding grooves in a sliding mode.

Preferably, the sliding block comprises a base, a limiting strip and a hinged end, wherein the limiting strip is protruded from two lateral sides of the base and extends to be limited in the limiting groove, the hinged end is arranged at one end of the base, and the hinged end is hinged to one end of the transmission rod.

Preferably, the back cover includes the caping, certainly first, the second lid side that form is extended to the caping both sides reaches through the back cover cavity that the caping encloses with two lid sides and establish, back cover cavity is equipped with at least a pair of first support wall on length direction, the both ends of first, second shaft body are spacing in on a pair of first support wall.

Preferably, the first and second cover sides of the back cover are correspondingly provided with a first avoiding groove between the first supporting walls, the transmission rod crosses the first avoiding groove, and the first avoiding groove provides a rotating space for the transmission rod.

Preferably, the transmission assembly further comprises a fourth clamping plate and a damping block clamped between the fourth clamping plate and the third clamping plate, the damping block is divided into two groups to clamp the first shaft body and the second shaft body respectively, and the damping block is fixed with the second shaft body and elastically clamped with the first shaft body.

In order to solve the technical problem, the application further provides a folding display device, which comprises the hinge mechanism and is attached to the folding screen on one side of the back cover, wherein the first folding plate and the second folding plate deviate from the folding screen.

In order to solve the above technical problem, the present application further provides a communication device, which includes the above foldable display device.

This application hinge mechanisms can connect first, second folded sheet, makes expansion or folding of first, second folded sheet pass through hinge mechanisms's drive assembly realizes, through setting up a pair of first axis body and at least a pair of second axis body, first, second axis body side by side and the cover are equipped with the gear of mutual interlock, and the transmission through a plurality of gears reduces the radius of gear.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application.

Fig. 1 is a perspective view of a communication device of the present application;

fig. 2 is an exploded perspective view of the communication device of the present application;

FIG. 3 is a perspective view of a foldable display device according to the present application;

FIG. 4 is a perspective view of a back cover of the foldable display device of the present application;

FIG. 5 is a perspective view of a folding plate and a lifting plate of the foldable display device of the present application;

FIG. 6 is a perspective view of the hinge mechanism and lift mechanism of the present application mounted to the back cover;

FIG. 7 is a perspective view of the hinge mechanism and lift mechanism of the present application assembled to the folding plate;

FIG. 8 is a perspective view of the hinge mechanism of the present application;

FIG. 9 is a perspective view of the slider and shaft of the hinge mechanism of the present application;

FIG. 10 is a perspective view of a drive assembly of the hinge mechanism of the present application;

FIG. 11 is an exploded perspective view of the drive assembly of the hinge mechanism of the present application;

FIG. 12 is a front view of the damper blade of the drive assembly of the hinge mechanism of the present application;

FIG. 13 is a cross-sectional view taken along line A-A of FIG. 10;

FIG. 14 is an exploded perspective view of the lift mechanism of the present application;

FIG. 15 is a perspective view of a lifting member of the present lift mechanism;

FIG. 16 is a perspective view of a rotating arm of the present lift mechanism;

FIG. 17 is a perspective view of the foldable display device of the present application in a folded state;

FIG. 18 is a view of the hinge mechanism and lift mechanism of the present application in conjunction with the back cover in a folded position;

fig. 19 is a transverse cross-sectional view of the foldable display device of fig. 17 in a folded state.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail and completely with reference to the following specific embodiments of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 1 to 3, the communication device of the present application includes first and

second folding plates

11 and 12, a lifting plate 50 located between the first and

second folding plates

11 and 12, a hinge mechanism 40 and a lifting mechanism 60 fixed to outer sides of the first and

second folding plates

11 and 12, a back cover 20 installed on outer sides of the first and

second folding plates

11 and 12 and connected to the hinge mechanism 40 and the lifting mechanism 60, first and

second housings

31 and 32, and a folding screen 80 attached to inner sides of the first and second folding plates 11 and 12 (as shown in fig. 19).

As shown in fig. 4 and fig. 6, the back cover 20 includes a cover top 21, first and

second cover sides

22 and 23 extending from two sides of the cover top 21, and a back cover cavity 24 enclosed by the cover top 21 and the two

cover sides

22 and 23. The outer surfaces of the cap top 21 and the first and

second cap sides

22, 23 form an arc-shaped outer surface. The back cover cavity 24 is sequentially provided with a pair of first supporting walls 251, two pairs of second supporting walls 261 and a pair of first supporting walls 251 in the length direction. In a specific implementation, at least one pair of first supporting walls 251 or one pair of second supporting walls 261 is provided, and a plurality of shaft holes are provided on the first supporting walls 251 and the second supporting walls 261. A gap is formed between the pair of first support walls 251 for mounting the hinge mechanism 40, and a gap is formed between the pair of second support walls 261 for mounting the elevating mechanism 60.

First avoiding grooves 253 are respectively formed in the two

cover sides

22 and 23 located between the pair of first supporting walls 251, and subsidence portions 254 are respectively formed on the two sides of the

cover sides

22 and 23 located in the first avoiding grooves 253 in a recessed manner. A second avoiding groove 263 is arranged between a pair of second supporting walls 261 corresponding to the

cover sides

22 and 23, respectively, and the second avoiding grooves 263 of the two

cover sides

22 and 23 are arranged in a staggered manner, that is, the two second avoiding grooves 263 are respectively close to one of the second supporting walls 261.

As shown in fig. 2, fig. 5 and fig. 7, the lifting plate 50 is disposed between the first and

second folding plates

11, 12, and the ends of the first and

second folding plates

11, 12 extend to form an extending portion 15 surrounding the lifting plate 50. The first and

second folding plates

11, 12 are provided with a sliding slot mechanism 13 at a position corresponding to the hinge mechanism 40, and the sliding slot mechanism 13 includes two parallel protrusions 131, a sliding slot 133 disposed between the two protrusions 131, and a limiting slot 134 disposed at the bottom of one side of the sliding slot 133 of the protrusion 131. And the positions of the first folding plate 11 and the second folding plate 12 corresponding to the lifting mechanism 60 are provided with a limiting mechanism 14. The limiting mechanism 14 includes two limiting pieces 141 formed by protruding and extending from the surfaces of the first or

second folding plates

11, 12, an accommodating space 143 between the two limiting pieces 141, a connecting piece 142 connected to the two limiting pieces 141 at a side away from the lifting plate 50, and an arc-shaped groove 144 opened on the two limiting pieces 141. The arc-shaped grooves 144 of the two limiting pieces 141 are symmetrically arranged, and the arc-shaped grooves 144 extend to the surface of the first or

second folding plate

11, 12 at the side close to the lifting plate 50. The connecting piece 142 helps to reinforce the strength of the two stopper pieces 141. The two limiting mechanisms 14 correspond to the two second avoiding grooves 263 of the back cover 20, respectively.

As shown in fig. 7 to 13, the hinge mechanism 40 includes a sliding block 41, a transmission assembly 43, and a transmission rod 42 rotatably hinged to the sliding block 41 and the transmission assembly, respectively. The sliding block 41 is fitted in the sliding groove 133 between the two protrusions 13, and the sliding block 41 includes a base 411, a limiting strip 412 protruding from two lateral sides of the base 411 and formed to be limited in the limiting groove 134, and a hinge end 413 disposed at one end of the base 411. The transmission rod 42 includes a rod 421 and two

hinged ends

423 and 424 disposed at two ends of the rod 421. The rod 421 is substantially an arc-shaped bent structure, and an arc-shaped avoiding portion 422 is formed on one side of the rod 421 facing the lifting plate 50, and the arrangement of the arc-shaped avoiding portion 422 is helpful to increase the space width between the two rods 421, so that the inner folding screen 80 (as shown in fig. 19) can be folded with a larger R, thereby reducing the technical difficulty requirement on the folding screen 80.

The transmission assembly 43 includes a pair of first shafts 44, a pair of second shafts 45 disposed between the pair of first shafts 44, first to

fourth splints

481, 482, 483, 484 sequentially sleeved on the first and

second shafts

44, 45, four gears 46 sleeved on the first and

second shafts

44, 45 and clamped between the first and

second splints

481, 482, a spring 49 sleeved on the first shafts 44 and clamped between the second and

third splints

482, 483, and a damping block 47 clamped on the first shafts 44 and the second shafts 45 and disposed between the third and

fourth splints

483, 484. A fastener 485 fixed to the second shaft body 45 is provided on the outer side of the first and

fourth jaws

481, 484 to prevent the first and

fourth jaws

481, 484 from falling off the first or

second shaft body

44, 45. The first and

second shaft bodies

44, 45 are respectively provided with a

first end portion

441, 451 and a

second end portion

444, 454, the first and

second shaft bodies

44, 45 are provided with a

gear mounting portion

442, 452 corresponding to the sleeving position of the gear 46, the gear mounting portion 442 of the first shaft body 44 is irregular, preferably square, and when the gear 46 is sleeved on the first shaft body 44, the gear 46 and the first shaft body 44 are relatively fixed and can not rotate; the gear mounting portion 452 of the second shaft body 45 is circular, and when the gear 46 is sleeved on the gear mounting portion 452, the gear 46 can rotate around the second shaft body 45.

Referring to fig. 12 and 13, the damping blocks 47 are divided into two groups, each group holding a first shaft 44 and a second shaft 45. Each damping block 47 includes a block 471 and a first engaging groove 472 and a second engaging groove 473 formed at two ends of the block 471. The first engaging groove 472 is engaged with the first shaft 44, the second engaging groove 473 is engaged with the second shaft 45, and the damping

block mounting portions

443, 453 are disposed at positions of the first and

second shaft

44, 45 corresponding to the damping block 47. The damping block mounting portion 443 of the first shaft 44 is a circular structure, and the damping block mounting portion 453 of the second shaft 45 is provided with at least two clamping planes. The first engaging groove 472 is rotatable with respect to the first shaft 44, and the second engaging groove 473 is fixed and non-rotatable with respect to the second shaft 45. A plurality of concave portions 474 are disposed in the first engaging groove 472, that is, the first engaging groove 472 is substantially square, a radius of an inscribed circle of the first engaging groove 472 is smaller than a radius of the damping block mounting portion 443 of the first shaft 44, and when the first engaging groove 472 rotates around the damping block mounting portion 443 of the first shaft 44, an elastic friction force is provided, so that a positioning force at any position is realized.

The first and second ends 441, 451 of the first shaft 44 and the second shaft 45 of the hinge mechanism 40 are respectively positioned on the two first supporting walls 251 of the back cover 20. The driving lever 42 rotates across the first avoiding groove 253 of the back cover 20. The hinged ends 423 of the transmission rod 42 at one side of the first and

second folding plates

11, 12 are hinged to the inner sides of the first ends 441 of the two first shaft bodies 44, respectively, and the hinged ends 423 of the transmission rod 42 and the first shaft bodies 44 are fixed to each other and are not rotatable.

When the hinge mechanism 40 of the present application is operated, the first and

second folding plates

11 and 12 are folded or unfolded to drive the sliding block 41 to move in the sliding slot 133, and thus the driving rod 42 rotates to drive the first shaft 44 to rotate, the rotation of the first shaft 44 rotates the gear 46 thereon and transmits the gear 46 to the second shaft 45 to rotate, and the first engaging slot 472 of the damping block 47 provides an elastic force to the first shaft 44 to block the rotation of the first shaft 44, so as to position any position in the rotating process. The spring 49 provides elastic force to press the gear 46 and the damping block 47 from being locked in rotation.

The first shaft body 44 and the second shaft body 45 are arranged in parallel, and the diameter of the gear 46 can be reduced through the meshing transmission of four gears 46, so that the thickness of the hinge mechanism 40 is thinner; thus, a meshing transmission of 6 or 8 gears, preferably 4 gears, can be provided depending on the situation.

In practical implementation, if the thickness of the hinge mechanism 40 is not considered, the second shaft 45 of the hinge mechanism 40 may be omitted, and only two first shaft bodies 44 are provided, and the two gears 46 on the two first shaft bodies 44 are engaged for transmission.

The hinge mechanism 40 of the present application can connect the first and

second folding plates

11, 12, so that the first and

second folding plates

11, 12 can be unfolded or folded by the transmission assembly 43 of the hinge mechanism 40, and the damping blocks 47 respectively engage the first and

second shaft bodies

44, 45 to provide the first shaft body 44 with resistance against rotation, thereby realizing folding at any position of the foldable display device.

As shown in fig. 14 to 16, the lifting mechanism 60 includes a base 61 having a first rotating shaft 612 at two longitudinal ends, a lifting member 63 coupled to the first rotating shaft 612, a driving wheel 64 linked with the lifting member 63, and a transmission member 66 linked with the driving wheel 64. The bottom of the base 61 is fixed integrally with the elevating plate 50. The lifting member 63 includes a strip 631, a first gear 633 arranged on one side of one end of the strip 631 in the transverse direction, and a strip hole 632 formed in one end of the strip 631, which is far away from the first gear 633, wherein the strip hole 632 is sleeved on the first rotating shaft 612 on the outer side of the base 61 in the transverse direction. The transmission wheel 64 includes a second rotation shaft 641, and second and

third gears

643, 642 provided at one end of the second rotation shaft 641 and having different radii, wherein the second and

third gears

643, 642 and the second rotation shaft 641 are integrally formed, the radius of the second gear 643 is smaller than the radius of the third gear 642, and the second gear 643 meshes with the first gear 633. The transmission member 66 includes a main body portion 661, first and second coupling ends 663, 664 formed at both ends of the main body portion 661, and a fourth gear 665 formed laterally outside the second coupling end 664. The main body portion 661 has an arc-shaped bent structure in conformity with the driving rod 42 of the hinge mechanism 40, and an arc-shaped space 662 in conformity with the arc-shaped space 422 of the driving rod 42 is formed inside the main body portion 661. The fourth gear 665 is meshed with the third gear 642. The lifting mechanism 60 further includes a third shaft 65 passing through a shaft hole (not numbered) of the fourth gear 665 of the transmission member 66, and the third shaft 65 is further inserted into a shaft hole (not numbered) of the first gear 633 of the lifting member 63. A fourth rotating shaft 67 transversely penetrates through the first connecting end 664 of the transmission member 66, and the fourth rotating shaft 67 is fixed in the arc-shaped channel 144 of the limiting mechanism 14 of the first folding plate 11 and the second folding plate 12 and can rotate around the arc-shaped channel 144. The ends of the second rotating shaft 641 and the third rotating shaft 65 far from the base 61 are respectively fixed on a pair of second supporting walls 261 of the back cover 20. The lifting piece 63, the transmission wheel 64 and the transmission piece 66 are symmetrically arranged on two sides of the base 61.

The transmission member 66 spans two second avoiding grooves 263 which are relatively staggered between the second supporting walls 261 of the back cover 20.

Referring to fig. 6, 18 and 19, the lifting mechanism 60 operates according to the following principle:

when the first and

second folding plates

11, 12 are unfolded, the transmission member 66 rotates around the arc-shaped channel 144 of the limiting mechanism 14, the fourth gear 665 on the transmission member 66 drives the third gear 642 of the transmission wheel 64 to rotate, the second gear 643 integrated with the third gear 642 drives the first gear 633 of the lifting member 63 to rotate, the rotation of the first gear 633 enables the lifting member 63 to stand until the first rotating shaft 612 is located at the bottom of the strip-shaped hole 632, and the lifting member 63 continues to ascend and the base 61 ascends due to the continuous rotation, and finally the lifting plate 50 is driven to ascend, that is, the lifting plate 50 moves to ascend in a direction away from the back cover 20. When fully unfolded, the lifting plate 50 is raised to be flush with the first and

second folding plates

11, 12 to support the folding screen 80 in the unfolded state.

Conversely, when the first and

second folding plates

11, 12 are folded, the lifting plate 50 is lowered and moved toward the back cover 20 to avoid the folding area 82 of the folding screen 80 to prevent the folding screen 80 from being pressed.

The arc-shaped channel 144 on the limiting mechanism 14 controls the rotation path of the transmission member 66 to conform to the optimal folding path of the folding screen 80, and the lifting members 63, the transmission wheels 64 and the transmission member 66 are disposed at two longitudinal sides of the base 61, which are point-symmetric, so that the first and

second folding plates

11, 12 can be folded or unfolded at a uniform speed, that is, either side of the first and

second folding plates

11, 12 can be folded or unfolded at a certain angle, and the other side can also be folded or unfolded at the same angle by the lifting mechanism 60.

The lifting mechanism 60 of this application is still through the mode that sets up lifter plate 50, when folding, makes lifter plate 50 returns back lid 20 one side in order to dodge folding screen 80, and when expanding, lifter plate 50 rise to with first,

second folding plate

11, 12 parallel and level are in order to support folding screen 80, the problem of being destroyed easily by the weak change of the inside and outside cambered surface length that the folding in-process of expanding of folding screen 80 caused has been solved to the perfection.

As shown in fig. 17 to 19, after the foldable display device of the present application is folded, the space required by the folding or unfolding process is provided for the foldable screen 80 by the supplementary support and avoidance of the lifting plate 50. After the folding screen 80 is folded, the driving rod 42 of the hinge mechanism 40 and the driving member 66 of the lifting mechanism 60 form an arc-shaped space 662 at opposite inner sides thereof, so as to increase the space between the pair of driving rods 42 and the pair of driving members 66, and the folding screen is folded to be folded into a droplet-shaped structure 82 in the folding area between the driving rod 42 and the driving member 66, and the portions between the first and

second folding plates

11, 12 are completely attached to form the attaching portion 81. The setting of water droplet column structure 82 can increase the R angle of folding screen 80 reduces the technical degree of difficulty of folding screen 80, cooperates lifter plate 50 can accomplish when folding display device is folding completely, and the thickness of folding display device 80's back of the body lid 20 one side is unanimous with the open end, and the condition that one side is thick, one side is thin can not appear.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A hinge mechanism is characterized by comprising a first folding plate, a second folding plate, a back cover, a sliding block, a transmission rod and a transmission component, wherein the sliding block is respectively limited on the first folding plate and the second folding plate in a sliding way, the transmission rod is rotatably hinged with one end of the sliding block, the transmission component is fixedly hinged with the transmission rod, the transmission assembly comprises a pair of first shaft bodies, at least a pair of second shaft bodies arranged between the first shaft bodies, at least four gears which are sleeved on the first shaft bodies and the second shaft bodies and are mutually meshed, and a first clamping plate and a second clamping plate which are sleeved on the first shaft bodies and the second shaft bodies and are positioned at two ends of the four gears, the transmission rod is fixedly hinged with two first shaft bodies positioned at the outer side, the first shaft bodies are fixed with gears on the first shaft bodies and can not rotate, the second shaft body and the gear on the second shaft body can rotate relatively, and two ends of the first shaft body and the second shaft body are fixed on the back cover.

2. The hinge mechanism according to claim 1, wherein the first and second clamping plates are correspondingly provided with a plurality of shaft holes having centers of circles in the same straight line, the first and second shaft bodies are sleeved in the shaft holes, the second shaft body is arranged between the two first shaft bodies side by side, the second shaft body comprises four or six or eight, and each second shaft body is provided with gears engaged with each other.

3. The hinge mechanism as claimed in claim 2, wherein the transmission assembly further includes a third clamping plate and a spring clamped between the second clamping plate and the second clamping plate, the spring is sleeved outside the first shaft, the spring provides a resilient force to the second clamping plate and transmits the resilient force to the gear, so as to prevent the gear from being clamped by the first and second clamping plates and from rotating, and the second clamping plate is not fixed to the first and second shaft.

4. The hinge mechanism according to claim 3, wherein the first and second folding plates are provided with a sliding slot mechanism at a position corresponding to the sliding block, the sliding slot mechanism comprises two protrusions arranged side by side, a sliding slot opened between the two protrusions, and a limiting slot opened at the bottom of the protrusion at one side of the sliding slot, and the sliding block is slidably limited in the sliding slot.

5. The hinge mechanism as claimed in claim 4, wherein the slider includes a base, a limiting strip protruding from two lateral sides of the base to be limited in the limiting groove, and a hinge end provided at one end of the base, and the hinge end is hinged to one end of the driving rod.

6. The hinge mechanism according to claim 5, wherein the back cover includes a cover top, a first cover side and a second cover side extending from two sides of the cover top, and a back cover cavity defined by the cover top and the two cover sides, the back cover cavity has at least a pair of first supporting walls in a length direction, and two ends of the first and second shaft bodies are retained on the pair of first supporting walls.

7. The hinge mechanism as claimed in claim 6, wherein the first and second cover sides of the back cover are formed with first space-avoiding grooves between the first support walls, the driving rod crosses the first space-avoiding grooves, and the first space-avoiding grooves provide a rotation space for the driving rod.

8. The hinge mechanism as claimed in claim 3, wherein the transmission assembly further comprises a fourth clamping plate and a damping block clamped between the fourth clamping plate and the third clamping plate, the damping block is divided into two groups to clamp the first shaft and the second shaft respectively, and the damping block is fixed to the second shaft and elastically clamped to the first shaft.

9. A foldable display device comprising a hinge mechanism according to any one of claims 1 to 8 and a foldable screen attached to the first and second foldable panels on the side facing away from the back cover.

10. A communication apparatus comprising the foldable display device according to claim 9.