CN212151189U

CN212151189U - Display device

Info

Publication number: CN212151189U
Application number: CN202020382794.3U
Authority: CN
Inventors: 赵振宇; 唐泽达; 李屹
Original assignee: Appotronics Corp Ltd
Current assignee: Shenzhen Appotronics Corp Ltd
Priority date: 2020-03-23
Filing date: 2020-03-23
Publication date: 2020-12-15
Anticipated expiration: 2030-03-23
Also published as: WO2021190062A1

Abstract

The application discloses display device, this display device includes: the screen body is used for winding/unwinding the screen body; the lifting part is connected with the scroll body through the screen body so as to unreel the screen body from the scroll body; the power part is used for providing power to enable the scroll body to wind the screen body; the lifting part and the power part have a rotation speed difference so as to enable the screen body to generate tension in the winding/unwinding process; when the screen body unreels, the rotational speed of lift portion is greater than the rotational speed of power portion, when the screen body rolling, the rotational speed of power portion is greater than the rotational speed of lift portion. The power part comprises a driving part and a tension control part, the tension control part can actively control the torque between the driving part and the scroll body according to the difference of the tension of the screen body in the winding/unwinding process, so that the stable and controllable winding/unwinding of the screen body is realized, and the service life of the display device can be prolonged.

Description

Display device

Technical Field

The present application relates to the field of display device technology, and in particular, to a display device.

Background

The lifting screen is a product which utilizes the characteristic that the flexible screen can be curled and adopts a certain mechanical device to enable the screen to be unfolded or rolled as required, and has the characteristics of attractive appearance and small occupied space. Generally, the lifting screen needs to be lifted, so that the screen is ensured to have proper tension when being unfolded and certain stability is kept, and the lifting screen has important significance for products.

The inventor of the present application has found in long-term research and development that most of the common flexible screens on the market today are passive tensioning designs, i.e. a spring (torsion spring or coil spring) is used to provide the tensioning force. The lifting screen has large tension fluctuation in the unfolding/rolling process, and has adverse effects on the actual effect and the structural life.

SUMMERY OF THE UTILITY MODEL

The technical problem that this application mainly solved provides a display device, can make the screen body tensile force steady controllable when rolling/expansion, promotes display device's life.

In order to solve the technical problem, the application adopts a technical scheme that: provided is a display device including: the screen body is used for winding/unwinding the screen body; the lifting part is connected with the scroll body through the screen and is used for unreeling the screen body from the scroll body; the power part is connected with the scroll body to provide power to enable the scroll body to wind the screen body; the lifting part and the power part have a rotation speed difference so that the screen body generates tension in the winding/unwinding process to keep the flatness of the screen; in the screen body unreeling process, the rotating speed of the lifting portion is greater than that of the power portion, and in the screen body reeling process, the rotating speed of the power portion is greater than that of the lifting portion.

The power part comprises a driving part and a tension control part, the driving part is connected to the reel body through the tension control part to drive the reel body to reel the screen body, and the tension control part is used for actively controlling torque between the driving part and the reel body, so that stable reeling/unreeling of the screen body is realized.

Wherein the tension control unit generates a torque between the driving unit and the spool body by means of a frictional force.

Wherein, the tip of spool body is provided with the friction plate, and tension control portion includes: the shaft core is connected with the driving part; the first pressing piece and the second pressing piece are arranged on the shaft core at intervals along the axial direction of the shaft core;

the friction plate is located between the first pressing piece and the second pressing piece.

Wherein, axle core, first compressing tightly piece and second compressing tightly piece coaxial setting.

The tension control part further comprises a compression nut, and the compression nut is located on one side of the first compression sheet and used for adjusting the compression force between the first compression sheet and the friction plate, and between the second compression sheet and the friction plate.

The first pressing piece and the second pressing piece are identical in shape.

Wherein, the tension control part generates torque between the driving part and the reel body in an electromagnetic mode.

Wherein, the tension control part enables torque to be generated between the driving part and the reel body in a magnetic powder mode.

The power part comprises a first power part and a second power part, the first power part comprises a first driving part and a first tension control part, the first driving part is connected with the first tension control part and is positioned at the first end of the reel body, the second power part comprises a second driving part and a second tension control part, and the second driving part is connected with the second tension control part and is positioned at the second end of the reel body.

The display device further comprises a support, and the scroll body is fixed on the support and can rotate around the central shaft of the scroll body.

The beneficial effects of the embodiment of the application are that: different from the prior art, in the display device of the application, the lifting part and the power part have a rotation speed difference, so that the screen body generates tension in the winding/unwinding process to keep the flatness of the screen; in the unwinding process of the screen body, the rotating speed of the lifting part is greater than that of the power part, and in the winding process of the screen body, the rotating speed of the power part is greater than that of the lifting part; meanwhile, the tension control part is connected with the scroll body and the driving part to actively control the torque between the driving part and the scroll body, so that the tension is stable and controllable when the screen body is rolled/unfolded, and the screen body can have better holding force when in a static state; in addition, the tensioning force of the screen body can be conveniently adjusted, and the screen has good adaptability.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of a display device provided in the present application;

FIG. 2 is an enlarged partial view of box A of FIG. 1;

fig. 3 is a schematic structural diagram of a first embodiment of a tension control portion in a display device provided in the present application;

FIG. 4 is a cross-sectional view of the tension control portion of FIG. 3;

fig. 5 is a schematic structural diagram of a second embodiment of a tension control portion in a display device provided in the present application;

fig. 6 is a schematic structural diagram of a third embodiment of a tension control portion in a display device provided in the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part 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.

At present, most of lifting screens in the market mainly adopt passive reels, and are mainly suitable for screens made of materials with higher flexibility. The passive tensioning design generally adopts a spring to provide tensioning force, and the tensioning force of the spring is in direct proportion to the deformation amount, so that the tensioning force of the screen is different when the passive lifting screen moves to different positions in the unfolding/rolling process, and the stability of the unfolding/rolling process of the screen cannot be ensured; and the screen may have large tension fluctuation in the process of unfolding/rolling, which has adverse effect on the service life of the screen.

In order to enable the force of the screen in the unfolding/rolling process to be kept controllable and stable, the application provides the display device, the active control type scroll is adopted to control the screen tension, and the display device can be suitable for screens with hard materials and large tension.

As shown in fig. 1 and fig. 2, fig. 1 is a schematic structural diagram of an embodiment of a display device provided in the present application, and fig. 2 is a partially enlarged view of a frame a in fig. 1, the display device including: a screen body 1, a scroll body 2, a lifting part (not shown), and a power part (not shown).

The screen body 1 is the screen main part that has the display function, for the realization to the rolling of screen body 1 with unreel, screen body 1 is flexible structure. One end of the screen body 1 is fixed on the scroll body 2, and the scroll body 2 is used for winding/unwinding the screen body 1. Optionally, the display device further comprises a support 7, and the reel body 2 is fixed to the support 7. Preferably, the reel body 2 can be fixed by the supports 7 at both ends and can rotate around the central axis of the reel body 2 to realize winding/unwinding of the screen body 1.

The screen body 1 is connected to the lift portion, and the lift portion can control screen body 1 certainly unreel in the spool body 2, and the power of lift portion turns into the moment of torsion of spool body 2 through the tensile force of screen body 1. Because the speed that the lifting part drives the reel body to rotate is not uniform, the tensioning force borne by the screen body 1 is not uniform. In order to enable the screen body 1 to be stably and uniformly tensioned when being wound/unwound and to realize uniform winding or unwinding, the display device of the embodiment further includes a power unit (not shown in the figure).

The power part is connected with the winding shaft body to provide power to enable the winding shaft body to wind the screen body 1, and the power part and the lifting part have a rotating speed difference to enable the screen body to generate tension in the winding/unwinding process so as to keep the flatness of the screen; in the screen body unreeling process, the rotating speed of the lifting portion is greater than that of the power portion, and in the screen body reeling process, the rotating speed of the power portion is greater than that of the lifting portion.

Specifically, the power portion includes a driving portion 3 and a tension control portion 4, wherein the driving portion 3 is connected to the reel body 2 through the tension control portion 4 to drive the reel body 2 to reel the screen body, and the tension control portion 4 is used for actively controlling the torque between the driving portion 3 and the reel body 2 to control the tension of the screen body 1, thereby realizing the smooth reeling/unreeling of the screen body 1.

In this embodiment, because the speed that the screen body 1 was expanded under the drive of lift portion is not at the uniform velocity, and the rotational speed of power portion is generally invariable, consequently, there is the rotational speed difference between the drive division 3 of power portion and the spool body 2 that is driven by the lift portion, and the purpose of tension control portion 4 design is exactly when drive division 3 with the lift portion produces the rotational speed difference, can active control produce invariable moment of torsion to spool body 2 to make the tensioning force that screen body 1 received steady, promote display device's life. In addition, the tension control unit 4 can also avoid the rotation lock of the driving unit 3 to reduce the damage to the driving unit 3.

Specifically, the driving portion 3 may include a motor and an output shaft, the motor may be directly connected to the output shaft or connected to the output shaft through a coupling or other transmission mechanism, and the output shaft is connected to the tension control portion 4 to generate a constant torque to the winding shaft body 2 through the tension control portion 4, so that the torque between the driving portion 3 and the winding shaft body 2 is controllable. In other embodiments, the driving portion 3 may also be driven by a transmission device such as a gear or a belt from an external power mechanism.

In this embodiment, the tension control portion 4 can actively control the torque between the driving portion 3 and the scroll body 2 in a friction manner according to the difference of the tension of the screen body 1 in the winding/unwinding process. The torque control is carried out through the friction force, the cost is low, the method is simple and convenient, and extra current input is not needed. Referring to fig. 3 and 4 again, fig. 3 is a schematic structural diagram of a first embodiment of a tension control portion 4 in a display device provided by the present application, fig. 4 is a cross-sectional view of the tension control portion 4 in fig. 3, and the tension control portion 4 includes: the axle core 41, the first pressing piece 42 and the second pressing piece 43.

Specifically, the shaft core 41 is connected to an output shaft (not shown) of the driving portion 3, and the shaft core 41 can be rotated by the output shaft of the driving portion 3. The first pressing piece 42 and the second pressing piece 43 are provided on the shaft core 41 at intervals in the axial direction of the shaft core 41. The spool body 2 is provided with a friction plate 21, the friction plate 21 is positioned at the end of the spool body 2, and the friction plate 21 is positioned between the first pressing piece 42 and the second pressing piece 43. The first pressing piece 42 and the second pressing piece 43 are used to clamp the friction plate 21 from both sides. In order to make the force applied to the friction plate 21 more uniform, the shaft core 41, the first pressing piece 42, and the second pressing piece 43 may be coaxially disposed.

The driving part 3 of the power part can drive the first pressing piece 42 and the second pressing piece 43 on the shaft core 41 to rotate at a first rotating speed, the lifting part enables the reel body 2 to rotate at a second rotating speed, when the first rotating speed is different from the second rotating speed, namely, when a rotating speed difference exists between the first pressing piece 42 and the second pressing piece 43 and the friction plate 21, a sliding friction force can be generated between the first pressing piece 42 and the second pressing piece 43 and the friction plate 21, the sliding friction force can generate a torque on the reel body, and therefore the effect of actively controlling the tensioning force of the screen body 1 is achieved. The sliding friction force can be actively controlled according to the difference of the tension when the screen body 1 is rolled/unreeled, so that the torque between the driving part 3 and the reel body 2 can be controlled, and the screen body 1 can be rolled/unreeled stably.

The magnitude of this sliding friction determines the magnitude of the torque to which the spool body 2 is subjected. Because screen body 1 is at rolling/unreel in-process, this slip frictional force size is invariable, and consequently the moment of torsion that the spool body 2 received is invariable to make screen body 1's tensile force steady even.

The magnitude of the sliding friction force depends on the pressing force between the first pressing piece 42 and the second pressing piece 43 and the friction plate 21 and the friction coefficient between their contact surfaces, regardless of the rotation speed. The torque to the reel body 2 can be controlled by adjusting the pressing force between the first and second

pressing pieces

42 and 43 and the friction plate 21 or adjusting the friction coefficient between their contact surfaces to control the tension of the screen body 1.

Alternatively, the pressing force between the first and second

pressing pieces

42 and 43 and the friction plate 21 may be adjusted by the pressing nut 44. A pressing nut 44 is provided at one side of the first pressing piece 42, and the pressing force between the first and second

pressing pieces

42 and 43 and the friction plate 21 is adjusted by adjusting the pressing nut 44. Among them, the pressing nuts 44 may be provided in 2 numbers and symmetrically provided along the shaft core 41 to make the pressing force distribution more uniform. In other embodiments, the number of compression nuts 44 may be selected based on the application.

In this embodiment, the pressing force between the first and second

pressing pieces

42 and 43 and the friction plate 21 can be easily adjusted by the pressing nut 44 to adjust the magnitude of the sliding friction, thereby controlling the tension of the screen body 1.

In other embodiments, materials with different friction coefficients may be attached to the contact surfaces of the first pressing piece 42 and the second pressing piece 43 and the friction plate 21 to change the friction coefficients between the first pressing piece 42 and the friction plate 21 and the second pressing piece 43, so as to change the magnitude of the sliding friction force to control the tension of the screen body 1.

Alternatively, the first pressing piece 42 and the second pressing piece 43 may be respectively disposed around the shaft core 41, and the shape of the first pressing piece 42 and the shape of the second pressing piece 43 may be the same, so that the force applied to the sliding friction plate 21 is more uniform. In other embodiments, the shapes of the first and second

pressing pieces

42 and 43 may also be different.

The working principle of the embodiment is as follows: one end of the screen body 1 is fixed on the scroll body 2 and can be rolled on the scroll body 2. In the screen body unreeling process, the rotating speed of the lifting portion is greater than that of the power portion, and in the screen body reeling process, the rotating speed of the power portion is greater than that of the lifting portion.

Specifically, when the screen body 1 is to be unreeled, the screen body 1 is driven by the lifting part to be outwards unfolded, and the reel body 2 is driven by the screen body 1 to rotate therewith. The driving portion 3 controlling the power portion rotates at a lower rotation speed than the reel body 2, and alternatively, the driving portion 3 may not rotate or reversely rotate so that there is a difference in rotation speed between the driving portion 3 and the reel body 2. Because, there is the difference in rotational speed in the both sides of tension control portion 4, the spool body 2 can rotate only to overcome preset moment of torsion, the size of this preset moment of torsion depends on the sliding friction power between first holding-down piece 42 and second holding-down piece 43 and the friction plate 21, because this sliding friction power is invariable, consequently preset moment of torsion is also invariable, be promptly at screen body 1 in the expansion process, can active control tension control portion 4, make the tensioning force that screen body 1 received steady controllable, can promote display device's life-span. Since the 2 positions of the reel body are fixed after being unfolded to the fixed position, the reel body 2 can be rotated unless external force overcomes the preset torque, so that the screen body 1 also has better holding power under the static state, the oscillation phenomenon can be reduced, and the display effect of the display device can be improved.

When the screen body 1 needs to be rolled up, the output shaft of the driving part 3 of the power part is controlled to be rolled up at a movement speed higher than that of the lifting part, at the moment, the two ends of the tension control part 4 also generate a rotation speed difference, and due to the existence of the rotation speed difference, sliding friction force generates stable torque to the scroll body 2 so as to roll up the screen body 1, namely, the screen body 1 can be actively controlled to be rolled up at the same torque all the time, the rolling process is stable, the screen body can be guaranteed to be rolled up on the scroll body 2 all the time, and the volume of the display device after being rolled up can be reduced.

The driving part 3 and the tension controlling part 4 may be located only at one end of the spool body 2 to save the production cost. In other embodiments, in order to make the stress of the screen body 1 more uniform, the driving part 3 and the tension control part 4 of the power part may be arranged in pairs, and the driving part 3 and the tension control part 4 arranged in pairs are respectively located at two ends of the reel body 2. Specifically, the power part includes a first power part and a second power part, the first power part includes a first driving part and a first tension control part, the first driving part is connected with the first tension control part and is located at a first end of the reel body, the second power part includes a second driving part and a second tension control part, and the second driving part is connected with the second tension control part and is located at a second end of the reel body. The first driving part and the first tension control part are symmetrically arranged with the second driving part and the second tension control part along the center parting line of the scroll body 2, so that the stress of the screen body 1 in the winding/unwinding process is more uniform.

In summary, in the display device provided in this embodiment, the tension control portion 4 adopts a friction control manner to generate a torque between the driving portion 3 and the scroll body 2, so that the tension applied to the screen body 1 during winding and unwinding is stable and controllable, which is beneficial to improving the service life of the display device; and the tension of the screen body 1 is convenient to adjust, and the adaptability to the screen body 1 is improved. In addition, in the display device, after the screen body 1 is unfolded, the spool body 2 can rotate only by overcoming the preset torque, so that the screen body 1 has better holding force in a static state, the oscillation phenomenon is reduced, and the display effect of the display device can be improved.

The present application further provides a display device of a second embodiment, different from the first embodiment, in which the tension control portion in this embodiment controls the torque between the driving portion and the reel body in an electromagnetic force manner, and this manner can conveniently adjust the torque applied to the reel body by controlling the magnitude of the current, so that the display device has stronger adaptability. Specifically, as shown in fig. 5, fig. 5 is a schematic structural diagram of a second embodiment of a tension control portion in a display device of the present application, and the tension control portion of the present embodiment includes: stator 51, rotor 54, magnet 53, elastic member 52, and cover plate 55.

Specifically, the stator 51 is connected to the spool body, i.e., the spool body can rotate the stator 51. The stator 51 is provided with a first inductor 56, and the first inductor 56 is capable of generating a first magnetic attraction force when energized. The cover plate 55 is fixed to the stator 51, and optionally, the cover plate 55 may be fixed to the stator 51 by bolts 57. In other embodiments, the cover plate 55 may also be fixed to the stator 51 by a connecting rod.

The rotor 54 is located between the stator 51 and the cover plate 55, and is disposed adjacent to the cover plate 55; the rotor 54 is connected to a driving part, the rotor 54 can be rotated by the driving part, and when the driving part and the elevating part rotate at different speeds, the rotor 54 rotates at a different speed from the cover plate 55, and sliding friction can be generated between the rotor 54 and the cover plate 55. The sliding friction force can generate a torque to the spool body, and thus the magnitude of the torque received by the spool body can be controlled by controlling the sliding friction force between the rotor 54 and the cover plate 55, thereby controlling the tension of the screen body.

In the present embodiment, the magnitude of the sliding friction is related to the pressing force between the cover plate 55 and the rotor 54 and the friction coefficient between their contact surfaces. The amount of torque to which the spool body is subjected can be adjusted by controlling the pressing force between the cover plate 55 and the rotor 54 and the coefficient of friction therebetween.

In the present embodiment, the pressing force between the cover plate 55 and the rotor 54 is changed by controlling the movement of the magnet 53 by controlling the magnitude of the current supplied to the first induction coil 56. Specifically, the magnet 53 is located between the stator 51 and the rotor 54, and is fixed to the stator 51 by the elastic member 52. When the first induction coil 56 is not energized, the magnet 53 abuts on the rotor 54 under the pressure of the elastic member 52, and presses the rotor 54 and the cover plate 55 together. When the first inductor 56 is energized, the first inductor 56 generates a first magnetic attraction force to enable the magnet 53 to move between the stator 51 and the rotor 54, thereby changing the pressing force between the rotor 54 and the cover plate 55. Specifically, the magnet 53 is movable in a direction away from the rotor 54 by the first magnetic attraction force, thereby changing the pressing force between the rotor 54 and the cover plate 55. The moving amplitude of the magnet 53 is related to the magnitude of the first magnetic attraction force, that is, the magnitude of the current passing through the first inductance coil 56, so that the pressing force between the cover 55 and the rotor 54 can be changed by only changing the magnitude of the current passing through the first inductance coil 56, thereby controlling the tension of the screen body.

In this embodiment, the torque between the driving portion and the reel body can be actively adjusted only by adjusting the magnitude of the current in the first inductance coil 56, and the adjustment method is simpler and is convenient to operate.

Alternatively, the elastic member 52 may be a spring. In other embodiments, the elastic member 52 may be a rubber member. In order to de-energize the magnet 53 for immediate demagnetization, the magnet 53 may be soft iron or silicon steel.

The structure of other components of the display device in this embodiment is the same as that in the first embodiment, and therefore, the description thereof is omitted.

Different from the first embodiment, in the tension control portion of the present embodiment, the winding shaft body drives the stator 51 to rotate, the driving portion drives the rotor 54 to rotate, and a rotation speed difference is generated between the stator 51 and the rotor 54, so that a sliding friction force is generated between the cover plate 55 fixed on the stator 51 and the rotor 54 to generate a constant torque to the winding shaft body, thereby stabilizing the tension of the screen body. The embodiment utilizes the electromagnetic force to initiatively adjust the size of the moment of torsion that the spool body received to control the tension of screen body, the moment of torsion of the spool body can be adjusted more conveniently to this embodiment, thereby the tensile force of screen body can be controlled more conveniently, make display device have stronger adaptability.

The present application further provides a display device of a third embodiment, which is different from the first embodiment in that the tension control portion controls the torque between the driving portion and the reel body by using magnetic powder. As shown in fig. 6, fig. 6 is a schematic structural diagram of a third embodiment of the tension control portion of the present application, and in this embodiment, the tension control portion includes an inner rotor 62, an outer rotor 61, and magnetic particles 64.

In this embodiment, the outer rotor 61 is connected with the driving portion, and the inner rotor 62 is connected with the spool body, and the driving portion can drive the outer rotor 61 to rotate promptly, and the spool body can drive the inner rotor 62 to rotate. The outer rotor 61 surrounds the inner rotor 62, the outer rotor 61 and the inner rotor 62 form an accommodating space, and the magnetic powder 64 is located in the accommodating space.

The outer rotor 61 is provided with a second inductance coil 63, the second inductance coil 63 can generate a second magnetic attraction force when being electrified, and the magnetic powder 64 can be arranged along the magnetic flux direction under the action of the second magnetic attraction force to form a magnetic powder chain so as to connect the inner rotor 62 and the outer rotor 61 through the magnetic powder chain, so that the inner rotor 62 and the outer rotor 61 have corresponding connection force when a rotation speed difference exists between the inner rotor 62 and the outer rotor 61. The second inductor 63 may be disposed inside the outer rotor 61 or outside the outer rotor 61, as long as the second inductor 63 can generate the second magnetic attraction force attracting the magnetic powder 64 after being energized.

When there is a difference in rotational speed between the inner rotor 62 and the outer rotor 61, the connection force of the magnetic powder chains enables the reel body 2 to generate a corresponding torque, i.e., the magnitude of the torque applied to the reel body 2 is related to the connection force of the magnetic powder chains. Therefore, the maximum torque which can be transmitted by the inner rotor 62 and the outer rotor 61 can be changed by adjusting the magnitude of the electrified current to change the connection force of the formed magnetic powder chains, so that the tension control of the screen body is realized.

When the second inductance coil 63 is not energized, the magnetic powder 64 can slide freely, the inner rotor 62 and the outer rotor 61 are not connected, and the inner rotor 62 and the outer rotor 61 can idle.

Different from the first embodiment, in the tension control portion of this embodiment, the reel body can drive inner rotor 62 to rotate, the drive portion drives outer rotor 61 to rotate, and be provided with magnetic powder 64 between inner rotor 62 and outer rotor 61, magnetic powder 64 receives the effect of second magnetism and can form certain connecting force between inner rotor 62 and outer rotor 61, when there is the difference in rotational speed between inner rotor 62 and the outer rotor 61, this connecting force can produce the moment of torsion to the reel, when connecting force is unchangeable, the moment of torsion that the reel body received is invariable also, thereby make the tension of screen body stable. And this embodiment utilizes magnetic 64 to come the initiative to adjust the size of the moment of torsion that the spool body received to come the tensile force of control screen body, the simple structure of the tension control portion of this embodiment, and can very conveniently adjust the moment of torsion of spool body, thereby can conveniently control the tensile force of screen, make display device have stronger adaptability.

The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.

Claims

1. A display device, characterized in that the display device comprises:

a screen body, a display screen and a display screen,

the reel body is used for reeling/unreeling the screen body;

the lifting part is connected with the scroll body through the screen body and is used for unreeling the screen body from the scroll body;

the power part is connected with the scroll body to provide power to enable the scroll body to wind the screen body;

the lifting part and the power part have a rotation speed difference so that the screen body generates tension in the winding/unwinding process to keep the flatness of the screen;

in the screen body unreeling process, the rotating speed of the lifting portion is greater than that of the power portion, and in the screen body reeling process, the rotating speed of the power portion is greater than that of the lifting portion.

2. The display device according to claim 1, wherein the power part comprises a driving part and a tension control part, the driving part is connected to the reel body through the tension control part to drive the reel body to reel the screen body, and the tension control part is configured to actively control a torque between the driving part and the reel body, so as to realize smooth reeling/unreeling of the screen body.

3. The display device according to claim 2, wherein the tension control portion generates a torque between the driving portion and the reel body by means of a frictional force.

4. The display device according to claim 3, wherein a friction plate is provided at an end of the reel body, and the tension control portion includes:

a shaft core connected to the driving part;

the first pressing piece and the second pressing piece are arranged on the shaft core at intervals along the axial direction of the shaft core;

5. The display device according to claim 4, wherein the shaft core, the first pressing piece, and the second pressing piece are coaxially disposed.

6. The display device according to claim 5, wherein the tension control portion further comprises a compression nut located at one side of the first pressing piece for adjusting a pressing force between the first and second pressing pieces and the friction plate.

7. The display device according to claim 4, wherein the first pressing piece and the second pressing piece are identical in shape.

8. The display device according to claim 2, wherein the tension control portion electromagnetically generates a torque between the driving portion and the reel body.

9. The display device according to claim 2, wherein the tension control portion generates torque between the driving portion and the reel body by means of magnetic powder.

10. The display device according to claim 2, wherein the power unit includes a first power unit and a second power unit, the first power unit includes a first driving unit and a first tension control unit, the first driving unit is connected to the first tension control unit and is located at a first end of the reel body, the second power unit includes a second driving unit and a second tension control unit, and the second driving unit is connected to the second tension control unit and is located at a second end of the reel body.

11. The display device according to claim 1, further comprising a support, wherein the reel body is fixed to the support and is rotatable about a central axis of the reel body.