Display device

A display device includes a display part including a display panel for displaying an image, a roller part configured to wind or unwind the display part, and a tape spring configured to move the display part in an upward and/or downward direction in conjunction with an operation of the roller part, and the roller part includes: a motor; a tape spring drum configured to accommodate the motor and connected to the motor, the tape spring drum being configured such that one end of the tape spring is fixed to the tape spring drum, and the tape spring drum winds or unwinds the tape spring; a tape spring casing configured to accommodate the tape spring drum and the tape spring; and a plurality of roll drums connected to two opposite sides of the motor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Korean Patent Application No. 10-2021-0192892 filed on Dec. 30, 2021 in the Korean Intellectual Property Office, the entire contents of which are hereby incorporated herein by reference.

BACKGROUND

Technical Field

The present disclosure relates to a display device, and more particularly, to a rollable display device capable of displaying images in a rolled configuration of the display device.

Description of the Related Art

Display devices are known for use as a monitor of a computer, a TV set, a mobile phone, and the like, and include an organic light-emitting display (OLED) configured to autonomously emit light, and a liquid crystal display (LCD) with a separate light source.

The range of application of display devices is being diversified from the examples above to personal mobile devices, and studies are being conducted on display devices having wide display areas with reduced volumes and weights.

In addition, recently, rollable display devices have attracted attention as a next-generation display device.

BRIEF SUMMARY

In an embodiment, a rollable display device includes display parts, lines, and the like on a substrate made of a flexible plastic material having flexibility and thus may display images even in a case in which the rollable display device is rolled up.

In one or more embodiments of the present disclosure, a display device is provided to improve spatial utilization by minimizing a volume of a roller part.

In one or more embodiments of the present disclosure, a display device is provided that is capable of overcoming challenges associated with a position of a display changing when the display part is wound or unwound.

In one or more embodiments of the present disclosure, a display device is provided that is capable of minimizing a space utilized for winding and unwinding operations.

Embodiments of the present disclosure are not limited to the above-mentioned embodiments, and other embodiments which are not mentioned above can be clearly understood by those skilled in the art from the following description.

According to an embodiment of the present disclosure, a display device includes: a display including a display panel configured to display an image; a roller configured to wind or unwind the display; and a tape spring configured to move the display in an upward/downward direction in conjunction with an operation of the roller, the roller including: a motor; a tape spring drum configured to accommodate the motor and connected to the motor, the tape spring drum being configured such that one end of the tape spring is fixed to the tape spring drum, and the tape spring drum winds or unwinds the tape spring; a tape spring casing configured to accommodate the tape spring drum and the tape spring; and a plurality of roll drums connected to two opposite sides of the motor.

Other detailed matters of the example embodiments are included in the detailed description with reference to the accompanying drawings.

According to the present disclosure, the roller, which winds or unwinds the display, and the motor, which operates the roller, are disposed in the same space. Therefore, it is possible to minimize a space required to operate the display device.

According to the present disclosure, it is possible to reduce a slip of the winding/unwinding roller and a slip of the display part caused by a difference in rotational speed between the winding/unwinding roller and the display part of the display device.

The benefits and advantages according to the present disclosure are not limited to the contents above, and additional benefits and advantages are included in the following description.

DETAILED DESCRIPTION

A size and a thickness of each component illustrated in the drawing may be illustrated for convenience of description, and the present disclosure is not necessarily limited to the size and the thickness of the component illustrated.

Hereinafter, a stretchable display device according to example embodiments of the present disclosure will be described in detail with reference to accompanying drawings.

Rollable Display Device

A rollable display device refers to a display device capable of displaying images even in a case in which the rollable display device is rolled up. The rollable display device may have higher flexibility than a general display device in the related art. A shape and configuration of the rollable display device may be freely changed depending on whether the rollable display device is in use, or not. Specifically, when the rollable display device is not in use, the rollable display device may be rolled up and stored with a reduced volume. On the contrary, when the rollable display device is in use, the rolled-up rollable display device may be unrolled again and used.

FIGS.1A and1Bare perspective views of a display device100according to an embodiment of the present disclosure.

First, referring toFIGS.1A and1B, the display device100includes a display part DP (which may also be referred to herein as a display DP or a display assembly DP) and a housing part HP (which may also be referred to herein as a housing HP or a housing assembly HP).

The display part DP is configured to display images to a user. For example, display elements and circuits, lines, and components for operating the display elements may be disposed on the display part DP. In this case, because the display device100according to an embodiment of the present disclosure is a rollable display device100, the display part DP may be configured to be wound or unwound. For example, the display part DP may include a display panel having flexibility so as to be wound or unwound, and a plurality of back bars. The display part DP will be described below in more detail with reference toFIGS.2to4B.

The housing part HP is a casing capable of accommodating the display part DP. The display part DP may be wound and accommodated in the housing part HP, as best shown inFIG.1B. The display part DP may be unwound and disposed outside the housing part HP, as best shown inFIG.1A. Movement of the display part DP into and out of the housing part HP is generally represented by arrow A inFIG.1A.

The housing part HP has an opening portion HPO through which the display part DP may move into and out of the housing part HP. The display part DP may move in an upward/downward direction while passing through the opening portion HPO of the housing part HP.

Meanwhile, the display part DP of the display device100may switch from a fully unwound state to a fully wound state or switch from the fully wound state to the fully unwound state. In an embodiment, the display part DP can also be arranged in a position between the fully unwound and fully wound states.

FIG.1Aillustrates the display part DP of the display device100in the fully unwound state. The fully unwound state is a state in which the display part DP of the display device100is disposed completely outside the housing part HP. That is, the fully unwound state may be defined as a state in which the display part DP is maximally unwound and disposed outside the housing part HP by a maximum amount in which the display part DP cannot be unwound any further in order to allow a user to see the image on the display device100.

FIG.1Billustrates the display part DP of the display device100in the fully wound state. The fully wound state is a state in which the display part DP of the display device100is accommodated in the housing part HP and cannot be wound any further. The configuration of the display part DP inside the housing part HP is advantageous in terms of an external appearance when the user does not see the image on the display device100. Therefore, the fully wound state may be defined as a state in which the display part DP is wound and fully accommodated in the housing part HP. In addition, in the fully wound state, the volume of the display device100decreases, and the display device100may be more easily stored and transported.

Display Part

FIG.2is a front elevational view of the display part DP of the display device100.FIG.3is a rear elevational view of the display part DP of the display device100. Referring toFIGS.2and3, the display part DP of the display device100includes a plurality of back bars110, a display panel120, a flexible film130(which may include one or more flexible films130), and a printed circuit board140.

The display panel120is a panel configured to display images to a user. The display panel120may include a display element configured to display images, a driving element configured to operate the display element, and lines configured to transmit various types of signals to the display element and the driving element.

The display panel120may include different display elements depending on the type of the display panel120. For example, in a case in which the display panel120is an organic light-emitting display panel, the display element may be an organic light-emitting element including an anode, an organic light-emitting layer, and a cathode. For example, in a case in which the display panel120is a liquid crystal display panel, the display element may be a liquid crystal display element. In addition, in a case in which the display panel120is a light-emitting display panel including an LED, the display element may be the LED. Hereinafter, the assumption is made that the display panel120is an organic light-emitting display panel. However, the display panel120is not limited to the organic light-emitting display panel. In addition, since the display device100is a rollable display device, the display panel120may be implemented as a flexible display panel so as to be wound around or unwound from the roller part, as described further below.

Referring toFIG.2, the display panel120includes a display area AA and a non-display area NA.

The display area AA is an area of the display panel120in which images are displayed. The display area AA may include a plurality of pixels, a plurality of subpixels constituting the plurality of pixels, and a drive circuit configured to operate the plurality of subpixels. The plurality of subpixels may be minimum units constituting the display area AA. The display element may be disposed in each of the plurality of subpixels. For example, the plurality of subpixels may each include the light-emitting element, such as the anode, a light-emitting part, and a cathode. However, the present disclosure is not limited thereto. In addition, the circuit(s) configured to operate the plurality of subpixels may include driving elements, lines, and the like. For example, the circuit(s) may include, but are not limited to, a thin-film transistor, a storage capacitor, a gate line, a data line, and the like.

The non-display area NA is an area in which no image is displayed. The non-display area NA surrounds an outer periphery of the display area AA. Various lines and circuits for operating the organic light-emitting element (or some other type of display element) in the display area AA are disposed in the non-display area NA. For example, the non-display area NA may include, but is not limited to, link lines for transmitting signals to the plurality of subpixels and the circuit in the display area AA. The non-display area NA may include a drive IC such as a gate driver IC and a data driver IC.

The flexible film130is a film having various types of components disposed on a flexible base film (i.e., a base film having flexibility). The flexible film130may have ductility. A partial region of the flexible film130, together with a ductile area MA, may be wound around or unwound from the roller part. The flexible film130may supply signals to the plurality of subpixels and the circuit in the display area AA. The flexible film130may be electrically connected to the display panel120. The flexible film130is disposed at one end of the non-display area NA of the display panel120, such as at a bottom end of the non-display area NA of the display panel120in a non-limiting example, and supplies a power voltage, a data voltage, and the like to the plurality of subpixels and the circuit in the display area AA. The number of flexible films130illustrated inFIG.2is an example, and the number of flexible films130may be changed and selected in accordance with design. However, the present disclosure is not limited thereto.

Meanwhile, for example, the drive IC such as the gate driver IC and the data driver IC may also be disposed on the flexible film130. The drive IC is a component configured to process data for displaying the image and process a driving signal for processing the data. The drive IC may be disposed in ways such as a chip-on-glass (COG) method, a chip-on-film (COF) method, and a tape carrier package (TCP) method depending on how the drive IC is mounted. However, for the convenience of description, the disclosure will proceed with a non-limiting example in which the drive IC is mounted on the flexible film130by the chip-on-film method. However, the present disclosure is not limited thereto.

The printed circuit board140is disposed at one end of the flexible film130, such as at a bottom end of the flexible film130in a non-limiting example, and connected to the flexible film130. The printed circuit board140is a component for supplying a signal to a drive IC. The printed circuit board140supplies various signals such as driving signal and data signals to the drive IC. Various types of components may be disposed on the printed circuit board140. For example, a timing controller, a power source unit (which may also be referred to as a power source), and the like may be disposed on the printed circuit board140.FIG.2illustrates one printed circuit board140. However, the number of printed circuit boards140may be changed and selected in accordance with design. The present disclosure is not limited thereto.

Meanwhile, although not illustrated inFIG.2, an additional printed circuit board connected to the printed circuit board140may be further disposed. For example, the printed circuit board140may be called a source printed circuit board (“source PCB” or “S-PCB”) on which a data drive part is mounted. The additional printed circuit board connected to the printed circuit board140may be called a control printed circuit board (“control PCB” or “C-PCB”) on which the timing controller and the like are mounted. The additional printed circuit board may be disposed in the roller part. The additional printed circuit board may be provided outside the roller part and disposed inside the housing part HP.

Referring toFIG.3, the plurality of back bars110may be disposed on the rear surface of the display panel120. The plurality of back bars110may support the display panel120. When the display panel120is wound around or unwound from the roller part, the back bars110may support the display panel120and inhibit the display panel120from being scratched and damaged. In other words, the back bars110may provide a supporting or supportive force for the display panel120. The plurality of back bars110may be referred to as an apron. The plurality of back bars110may be made of a plastic material. However, the present disclosure is not limited thereto. Meanwhile, the plurality of back bars110may be attached by a separate bonding layer or a foam tape, among other fasteners and fastening techniques.

FIGS.2and3illustrate that the plurality of back bars110are disposed on the rear surface of the display panel120. In an embodiment, a back cover having a plurality of opening portions may be additionally disposed between the display panel120and the plurality of back bars110. In addition, only the back cover may be used without the plurality of back bars110in some embodiments.

Coupling Structure Between Display Part, Roller Part, and Tape Spring

FIG.4Ais a front perspective view of the display device100uncoupled or separated from the housing part HP.FIG.4Bis a rear perspective view of the display device100uncoupled or separate from the housing part HP.FIGS.4A and4Bprovide additional detail of a coupling structure between the display part DP, a roller part150(which may also be referred to herein as a roller150), and a tape spring161of the display device100according to one or more embodiments of the present disclosure.

Referring toFIGS.4A and4B, the display device100according to embodiments of the present disclosure includes the tape spring161and a head bar162.

Referring toFIGS.4A and4B, the display part DP is connected to the roller part150, and the roller part150is configured to wind or unwind the display part DP. The tape spring161may move the display part DP in the upward and/or downward direction in conjunction with the operation of the roller part150. A specific method of operating the roller part150will be described with reference toFIGS.10A and10B, but the present disclosure is not limited thereto.

The tape spring161is disposed on a rear surface102of the display part DP. An upper end161U of the tape spring161is fixed to an upper end120U of the display panel120. A lower end161L of the tape spring161is fixed to the roller part150. Therefore, the tape spring161, together with the display part DP and display panel120, may be wound around, or unwound from, the roller part150and move the display part DP in the upward and/or downward direction in conjunction with the operation of the roller part150.

The tape spring161may be a bistable reeled composite (“BRC”) member, among other possibilities. The tape spring161may be wound or unwound in a column direction, i.e., a longitudinal or vertical direction of the tape spring161while being rolled or unrolled in a row direction, i.e., a width or horizontal direction of the tape spring161. When the tape spring161is kept unrolled (flat) in the row direction, the tape spring161is wound in the column direction. On the contrary, when the tape spring161is kept rolled in the row direction, the tape spring161has rigidity in the column direction and thus is unrolled in the longitudinal direction. In an embodiment, the tape spring161is pre-stressed and/or has elastic properties such that a shape of the tape spring161changes as the tape spring161is wound or unwound from the roller part150. More specifically, when the tape spring161is wound about the roller part150, the tape spring161flattens in a row direction (i.e., left to right in the orientation ofFIGS.4A and4B) to evenly wrap around the roller part150in the flat configuration. As the tape spring161is unwound from the roller part150, the tape spring161has a tendency to roll up into a rigid round tube structure, as shown at the upper end161U of the tape spring161. In this unrolled configuration, the tube structure of the tape spring161provides rigidity and support to the display part DP, and may in some instances assist with maintaining the display part DP in a flat configuration for viewing of images on the display panel120of the display part DP without distortion.

In this case, the rigidity of the tape spring161in the column direction is related to a degree to which the tape spring161is rolled in the row direction. That is, the degree to which the tape spring161is rolled in the row direction may be appropriately selected depending on the rigidity in the column direction that is suitable for the display part DP.

In the display device100according to the embodiment of the present disclosure, the tape spring161is unrolled or rolled in the row direction, such that the tape spring161may be wound or unwound in the column direction. Specifically, when the roller part150performs the winding operation, the tape spring161, together with the display panel120, may be wound in the column direction around the roller part150. When the roller part150performs the unwinding operation, the tape spring161, together with the display panel120, may be unwound in the column direction from the roller part150(i.e., the column direction and row direction shown inFIG.2andFIG.3).

In addition, when the roller part150performs the unwinding operation, the tape spring161, which is unwound in the column direction, may have rigidity in the column direction, thereby restricting swaying and torsion of the unwound display panel120. Therefore, the unwound display panel120may be kept flat by the rigidity of the tape spring161absent other external forces.

The head bar162may be disposed at an uppermost end of the display part DP. The head bar162is disposed to fix the display part DP and the upper end161U of the tape spring161. The head bar162may cover only a part of a surface of the display part DP adjacent to an edge of the uppermost end of the display part DP so as not to cover the image displayed on a front surface of the display part DP in some embodiments. For example, the display part DP and the head bar162may be fixed by a screw or other fastener, but the present disclosure is not limited thereto.

As shown inFIG.4Aand described in more detail elsewhere, the flexible film130and the printed circuit board are also configured to be wound and unwound about the roller part150.

Hereinafter, a specific configuration of the roller part150will be described with reference toFIGS.5to8B.

Configuration of Roller Part

FIG.5is an exploded perspective view of the display device100absent the housing part HP in one or more embodiments.FIG.6Ais an exploded perspective view illustrating a motor, a tape spring drum, a tape spring casing, and a tape spring guide of the roller part150of the display device100according to one or more embodiments of the present disclosure.FIG.6Bis a perspective view of an assembled state of the motor, the tape spring drum, the tape spring casing, and the tape spring guide of the roller part150of the display device100according to at least some embodiments of the present disclosure.FIG.7Ais an exploded perspective view illustrating a base plate and a roll drum of the roller part150of the display device100according to one or more embodiments of the present disclosure.FIG.7Bis a perspective view illustrating an assembled state of the base plate and the roll drum of the roller part150of the display device100according to some embodiments of the present disclosure.FIG.8Ais a perspective view illustrating a spiral spring disposed in the roller part150of the display device100according to one or more embodiments of the present disclosure.FIG.8Bis a perspective view of the roller part150of the display device100according to one or more embodiments of the present disclosure.

As will be explained in more detail with reference toFIGS.5to8B, the roller part150may include a motor151, a tape spring drum152, a tape spring casing153, a plurality of roll drums154, a base plate155, and a tape spring guide156.

Beginning withFIGS.5to6B, the motor151may be disposed at a central portion of the roller part150that is an innermost side of the roller part150. In other words, the motor151may be an internal center of the roller part150with the other features of the roller part150arranged around, and to the outside of, the motor151. The motor151may rotate the roller part150clockwise or counterclockwise. In an embodiment, the motor151is an electric motor operable to provide rotational force to rotate the roller part150. The motor151may therefore be connected to a separate external power source or a power source integrated with the display device100, such as an embedded battery, to supply the motor151with power.

Referring toFIGS.5and6A, the tape spring drum152may have a generally cylindrical shape. The tape spring drum152is connected to the motor151while also accommodating the motor151inside an axial bore152A of the tape spring drum152. Specifically, as illustrated inFIG.6A, the tape spring drum152may be connected to the motor151by a motor fixture151F disposed on one side surface152F (i.e., a first side surface152F) of the tape spring drum152and configured to cover the motor151. The motor fixture151F may be disposed to fix the motor151to the tape spring drum152. Therefore, the tape spring drum152may be rotated clockwise or counterclockwise by an operation of the motor151. In an embodiment, the motor fixture151F is provided in a form factor of a circular plate with holes151H for receiving fasteners151R to couple the tape spring drum152to the motor151. The plate may have a size and arrangement that overlaps both a portion of the motor151and a portion of the tape spring drum152to facilitate the coupling. Further, the holes151H may be arranged around a central hole151C through the motor fixture151F that accommodates a drive151D of the motor151(i.e., the drive151D passes through the central hole151C) and enables the drive151D to interface with other aspects of the motor part151, as explained further elsewhere.

One end of the tape spring161, such as the lower end161L shown inFIG.5, is fixed to the tape spring drum152. When the tape spring drum152is rotated clockwise or counterclockwise by the motor151, the tape spring161may be wound around or unwound from the tape spring drum152via the coupling between the lower end161L of the tape spring161and the tape spring drum152. That is, the tape spring drum152may be configured to wind or unwind the tape spring161.

Meanwhile, a tape spring drum extension portion152E having a shape extending outward may be disposed at the other side surface152S (i.e., a second side surface152S opposite to the first side surface152F) of the tape spring drum152. That is, as illustrated inFIGS.6A and6B, the tape spring drum extension portion152E may be disposed to protrude outward from the other side surface152S of the tape spring drum152. In an embodiment, the tape spring drum152and tape spring drum extension portion152E have different diameters to in a step down or step up configuration. In a non-limiting example, and as shown inFIG.5, the tape spring drum152may have a diameter that is greater than a diameter of the tape spring drum extension portion152E. Further, a spiral spring170may be disposed on the tape spring drum extension portion152E (FIG.5). Therefore, when the spiral spring is wound or unwound, the spiral spring170may maintain the display part DP in a flat state while applying tension to the display part DP. In this case, a specific configuration of the spiral spring170will be described below with reference toFIGS.8A to9C.

The tape spring casing153may be configured to accommodate the tape spring drum152and the tape spring161. Specifically, the tape spring casing153may be disposed to surround an outer peripheral surface1520of the tape spring drum152. Further, the tape spring casing153may have a shape that enables the tape spring161to be wound around or unwound from the tape spring drum152. For example, as illustrated inFIGS.5and6A, the tape spring casing153may have a cylindrical shape having a C-shaped cross-section in order to provide a cylindrical outer surface for winding the tape spring161while also providing an aperture153A so that the tape spring161can pass through the aperture153A for attachment to the tape spring drum162accommodated in the tape spring casing153. The tape spring casing153may also have a different shape that is at least partially opened so that the tape spring161may pass through the tape spring casing153. However, the present disclosure is not limited thereto.

The tape spring casing153may be configured so as not to be rotated by the operation of the motor151. For example, the tape spring casing153may be fixed inside the housing part HP. Therefore, the tape spring casing153may not rotate even though the tape spring drum152accommodated in the tape spring casing153is rotated by the operation of the motor151. As a result, the tape spring casing153may be fixed and static, while also providing for rotational motion of the tape spring drum152inside the tape spring casing153via motor151to wind and unwind the tape spring161about the tape spring drum152.

Referring toFIGS.5to6B, a plurality of tape spring casing sides153S may be disposed at two opposite sides of the tape spring casing153. The tape spring casing sides153S may cover side surfaces of the tape spring drum152and the motor151accommodated in the tape spring casing153. Therefore, the plurality of tape spring casing sides153S may be configured such that the motor151and the tape spring drum152are more stably accommodated in the tape spring casing153. In this case, as illustrated inFIGS.5to6B, the tape spring casing153and the plurality of tape spring casing sides153S may be configured to be separable. However, the tape spring casing153and the plurality of tape spring casing sides153S may be integrated as a single, unitary component. The present disclosure is not limited thereto. In an embodiment, the roller part150includes two tape spring casing sides153S corresponding to opposite sides of the roller part150that may be different from each other. In the orientation ofFIG.6AandFIG.6B, the left tape spring casing side153S may be generally closed, except for a central hole153C1accommodating the drive151D of the motor151and enabling rotational motion of the drive151D relative to the left tape spring casing side153S. The right tape spring casing side153S may have a central hole153C2accommodating the tape spring drum extension portion152E. As a result, a diameter of the hole153C1of the left tape spring casing side153S is less than a diameter of the hole153C2of the right tape spring casing side153S. Each of the tape spring casing sides153S may also include a protrusion153P, that may assist with securing the roller part150inside the housing part HP. The tape spring casing sides153S may also have the same configuration, or some other arrangement, in some embodiments.

Meanwhile, referring toFIGS.5to6B, a tape spring guide156(which may also be referred to herein as a guide156or guide element156) may be further disposed on the tape spring casing153. The tape spring guide156may be connected to the tape spring casing153at a position corresponding to the position of the tape spring161accommodated in the tape spring casing153. In an embodiment, the tape spring guide156is received in a tape spring guide slot156S (FIG.6A) in the tape spring casing153. The tape spring guide156includes an extension156E and a tip156T coupled to, or integrally formed with, with the extension156E. The extension156E may have a square or rectangular cross-sectional shape that is normal or perpendicular to a lower end face153E of the tape spring casing153that includes the tape spring guide slot156S. As a result, the extension156E generally extends away from the tape spring casing153in a direction perpendicular to the end face153E. The tip156T of the tape spring guide156is positioned normal or perpendicular to the extension153E and has a different shape than the extension156E. More specifically, the tip156T includes an outer surface including a flat and planar portion156T1that is similar to the outer surfaces of the extension156E, except that the flat and planar portion156T1may have a greater width than surfaces of the extension156E. The outer surface of the tip156T further includes a curved portion156T2that may correspond to a curvature of the tape spring161in the unwound configuration. The flat and planar portion156T1may assist with accommodating the tape spring guide156inside the housing part HP, while the curved portion156T2may face the tape spring161and assist with guiding the tape spring161, as described further with reference toFIG.8AandFIG.8B. Therefore, the tape spring guide156may guide an operation of winding or unwinding the tape spring161accommodated in the tape spring casing153.

Referring toFIG.6A, a plurality of first bearings BR1may be disposed between the two opposite sides of the tape spring drum152and the plurality of tape spring casing sides153S. The plurality of first bearings BR1may support the two opposite sides of the tape spring drum152so that the tape spring drum152may rotate relative to the tape spring casing153. In an embodiment, the first bearings BR1are implemented as rings that reduce a coefficient of friction to support rotation of the tape spring drum152relative to the tape spring casing153. The first bearings BR1may include ball bearings, rollers, wheels, and the like.

Referring toFIG.5, a plurality of second bearings BR2may be disposed outside the plurality of tape spring casing sides153S. The plurality of second bearings BR2may support the plurality of roll drums154so that the plurality of roll drums154described further below may rotate relative to the tape spring casing153. The second bearings BR2may be the same as, or different from, the first bearings BR1. In an embodiment, the number and arrangement of the first and second bearings BR1, BR2are selected based on design factors.

The plurality of roll drums154are disposed outside the plurality of second bearings BR2, which are disposed outside the plurality of tape spring casing sides153S.

Referring toFIGS.7A and7B, the roll drums154may have a cylindrical shape as a whole, but a part of the roll drum154may have a flat surface. That is, a portion154F of an outer peripheral surface154P of the roll drum154is flat, and the remaining portion of the outer peripheral surface is curved. In an embodiment, and as illustrated inFIGS.5and7A, the plurality of roll drums154may each include the roll drum154having a cylindrical shape, and roll drum sides154S configured to cover side surfaces of the roll drum154and accommodate the second bearings BR2. However, the roll drum154and the roll drum sides154S may be integrated as a single, unitary, integral component in some embodiments. The present disclosure is not limited thereto.

The plurality of roll drums154may be connected to the motor151. For example, the plurality of roll drums154may be connected directly to the motor151. Alternatively, the plurality of roll drums154may accommodate the motor151and be connected indirectly to the motor151by being connected to the tape spring drum152, which is configured to be rotated by the motor151. However, the method of connecting the plurality of roll drums154and the motor151may be variously changed in accordance with design and the present disclosure is not limited to the above non-limiting examples.

The plurality of roll drums154are connected to the motor151, such that the plurality of roll drums154may be rotated clockwise or counterclockwise by the operation of the motor151. In this case, the tape spring drum152and the plurality of roll drums154, which accommodate the motor151and are rotated by the operation of the motor151, may rotate in the same direction when the motor151operates. That is, the roll drums154, which is configured to rotate in the same direction as the tape spring drum152, may also be configured to rotate relative to the tape spring casing153, which is held fixed in some embodiments.

Meanwhile, referring toFIGS.5and7A, the plurality of second bearings BR2in the roller part150may include a total of four second bearings BR2respectively disposed at the two opposite sides of each of the plurality of roll drums154. Therefore, the plurality of second bearings BR2may support the two opposite sides of the plurality of roll drums154so that the plurality of roll drums154may rotate relative to the tape spring casing153.

Referring toFIGS.7A and7B, the base plate155may be connected to the plurality of roll drums154and include a planar portion, such as opposing flat and planar major surfaces155F where “major” means the largest surface area of any surface of the base plate155. Specifically, the base plate155may be disposed on the flat portion154F of the outer peripheral surface154P of each of the plurality of roll drums154.

The printed circuit board140of the display part DP may be disposed on the planar portion155F of the base plate155. Therefore, when the roller part150performs the winding or unwinding operation, the planar portion of the base plate155may support the printed circuit board140in a flat shape among the components of the display part DP wound around the roller part150.

Referring toFIGS.8A and8B, the spiral spring170may be disposed on the tape spring drum extension portion152E. Specifically, one end171(i.e., a first send171) of the spiral spring170is connected to the roll drum154, and the other end172(i.e., a second end172) of the spiral spring170is connected to the tape spring drum152. That is, the spiral spring170may be disposed in a space between the roll drum154and the tape spring drum extension portion152E. For example, one end171of the spiral spring170may be connected to the roll drum154by being inserted into an opening portion formed in the roll drum154. The other end172of the spiral spring170may be connected to the tape spring drum extension portion152E by being inserted into an opening portion formed in the tape spring drum extension portion152E. In an embodiment, the ends171,172of the spiral spring170are implemented as a bent tab with a “C”-shaped cross section that are inserted into corresponding slits or channels152C in the roll drum154and the tape spring drum extension portion152E to couple the spiral spring170to the roll drum154and the tape spring drum extension portion152E. However, the present disclosure is not limited thereto and other configurations are possible, including the use of various fasteners, tapes, adhesives, and the like.

The spiral spring170is a spiral member having an elastic force. The spiral spring170may apply a force in a winding direction of the roller part150by using tension of the spring. That is, the elastic force accumulated in the spiral spring170may increase when the display part DP is wound. Therefore, when the display part DP is fully unwound, the tension is released and applied to the display part DP, such that the display part DP may be kept flat. Further, the display part DP may be more easily wound.

FIG.8Billustrates the assembled roller part150with the roller drums154coupled to opposite sides of the tape spring casing153and the base plate155coupled to the flat portions154F of the roller drums154and extending across the tape spring casing153. In an embodiment, the base plate155provides additional rigidity to the roller part155and also enables uniform rolling of the roller part150, in addition to the features and benefits described above. The tape spring casing153may be held static or stationary by the housing part HP while the remaining portions of the roller part150rotate to wind or unwind the display part DP about the roller part150, and also to wind and unwind the tape spring161about the tape spring drum152.

Hereinafter, a specific operation of the spiral spring170will be described with reference toFIGS.9A to9C.

Operation of Spiral Spring

FIGS.9A to9Care cross-sectional views illustrating an operation of the spiral spring170during a winding or unwinding operation of the roller part150of the display device100. For the convenience of description,FIGS.9A to9Cillustrate only the spiral spring170, the tape spring drum extension portion152E, and the roll drum154of the roller part150among the components of the display device100.

Referring toFIGS.9A to9C, in the display device100, both the roll drum154connected to one end171of the spiral spring170and the tape spring drum extension portion152E connected to the other end172of the spiral spring170are configured to rotate. That is, both one end171and the other end172of the spiral spring170are configured to be rotatable. Therefore, energy stored in the spiral spring170may be maintained at a predetermined level. Further, it is possible to compensate for a difference in slip between the display part DP and the roller part150without causing damage to the display part DP.

Referring toFIG.9A, in the display device100according to at least one embodiment, a central axis171X through the one end171of the spiral spring170may be disposed on the same line as, or aligned with and parallel to, a central axis172X through the other end172of the spiral spring170.

Referring toFIG.9B, when the roll drum154rotates counterclockwise by 90 degrees, the one end171of the spiral spring170may rotate counterclockwise by 90 degrees, and the other end172of the spiral spring170may rotate counterclockwise by about 45 degrees due to the difference in diameter between the roll drum154and the tape spring drum extension portion152E. The one end171of the spiral spring170connected to the roll drum154may rotate together with the roll drum154. The other end172of the spiral spring170connected to the tape spring drum extension portion152E may rotate as the energy stored in the spiral spring170increases to a predetermined level associated with rotation of the tape spring drum extension portion152E, or higher. Specifically, when the roll drum154and the one end171of the spiral spring170begin to rotate, the spiral spring170may be further wound around the tape spring drum extension portion152E, and the energy stored in the spiral spring170may therefore gradually increase. The spiral spring170is characterized by returning back to the original state when the spiral spring170is deformed by an external force. Therefore, when the spiral spring170is deformed as the one end171of the spiral spring170is rotated by an external force applied to the roll drum154, the other end172of the spiral spring170may rotate in the same direction as the one end171of the spiral spring170so that the spiral spring170returns to the original state, i.e., the state illustrated inFIG.9Ain which the central axis171X of one end171of the spiral spring170and the central axis172X of the other end172of the spiral spring170are disposed on the same line.

In an embodiment, the other end172of the spiral spring170may not rotate simultaneously together with the one end171of the spiral spring170. However, the other end172of the spiral spring170may rotate when the energy stored in the spiral spring170increases to a predetermined level or higher. Specifically, the other end172of the spiral spring170is fixed to the tape spring drum extension portion152E, and a predetermined force is utilized to rotate the tape spring drum extension portion152E. Therefore, the other end172of the spiral spring170and the tape spring drum extension portion152E may rotate after additional energy capable of rotating the tape spring drum extension portion152E is stored in the spiral spring170by rotation of the one end171.

Referring toFIG.9C, when the roll drum154rotates by an additional 90 degrees counterclockwise, the one end171of the spiral spring170may further rotate by 90 degrees counterclockwise, and the other end172of the spiral spring170may rotate counterclockwise while maintaining an angle at a predetermined level with respect to the one end171of the spiral spring170. There may be a difference of about 45 degrees between the central axis171X of one end171of the spiral spring170connected to the roll drum154and the central axis172X of the other end172of the spiral spring170connected to the tape spring drum extension portion152E in some embodiments. The difference may also be about 45 degrees (i.e., between 42 degrees and 48 degrees) or more or less than 45 degrees, such as any value between and including 25 degrees to 65 degrees, among others. Even though the one end171of the spiral spring170and the roll drum154continuously rotate, a difference in angle is maintained at a predetermined level between the central axis171X of the one end171of the spiral spring170and the central axis172X of the other end172of the spiral spring170. Therefore, the energy stored in the spiral spring170may be maintained at a predetermined level that is associated with a difference between the central axis171X and the central axis172X being approximately 45 degrees in some embodiments. In the display device100according to at least some embodiments of the present disclosure, the tape spring drum extension portion152E and the roll drum154are rotatably connected, and both the one end171and the other end172of the spiral spring170are configured to be rotatable. Therefore, it is possible to maintain a tensile force of the spiral spring170at a level that may compensate for a slip of the display part DP and a slip of the roller part150without damaging the display part DP. In other words, the stored energy in the spiral spring170during rotation of the roller part150is maintained throughout rotation of the roller part150in order to maintain a tensile force in the spiral spring170that compensates for a slip of the display part DP and a slip of the roller part150during operation.

Winding and Unwinding Operations of Roller Part

FIGS.10A and10Bare cross-sectional views illustrating the winding and unwinding operations of the roller part150of the display device100according to one or more embodiments of the present disclosure. For the convenience of description,FIGS.10A and10Billustrate only the motor151, the tape spring drum152, the tape spring casing153, and the tape spring guide156among the components of the roller part150.

Referring toFIGS.10A and10B, in the display device100according to the present disclosure, when the roller part150performs the winding or unwinding operation, the display part DP may be wound around or unwound from the outer peripheral surface of the roller part150, and the tape spring161connected to the head bar162may be disposed to be accommodated in the roller part150, or to extend from the roller part150, respectively.

First, referring toFIG.10A, the tape spring161may be accommodated in the roller part150when the roller part150is wound. Specifically, the tape spring161may be accommodated between the tape spring drum152, which is rotated by the motor151, and the tape spring casing153that is fixed in the housing part HP so as not to rotate in the display device100. In an embodiment, the tape spring161may be connected to the tape spring drum152and wound around the outer peripheral surface1520of the tape spring drum152.

Further, the display part DP, which is connected to the tape spring161by the head bar162, may be wound around an outer peripheral surface150P of the roller part150. That is, the display part DP may be disposed along an outer peripheral surface1530of the tape spring casing153of the roller part150. Although not illustrated inFIG.10A, the display part DP may be connected to the plurality of roll drums154disposed at the two opposite sides of the tape spring casing153, connected to the motor151disposed in the tape spring casing153, and configured to rotate. Therefore, even though the tape spring casing153is fixedly disposed so as not to rotate in the display device100, the display part DP may be wound along the outer peripheral surface of the tape spring casing153by the rotation of the plurality of roll drums154.

Next, referring toFIG.10B, the tape spring161may be extended from the inside of the roller part150when the roller part150performs the unwinding operation. Specifically, the tape spring161may be unwound from the tape spring drum152by the rotation of the tape spring drum152. In this case, the tape spring161may be unwound from the tape spring drum152and unrolled in the width direction by the tape spring guide156while maintaining rigidity in the upward/downward direction.

As a result, the head bar162connected to the upper end of the tape spring161may move in the upward direction. The display part DP connected to the head bar162may also move in the upward direction, with the weight of the head bar162and the display part DP being supported, at least in part, by the tape spring161. Therefore, the display part DP may be unwound from the outer peripheral surface1530of the tape spring casing153of the roller part150.

Meanwhile, referring toFIGS.10A and10B, the display part DP may have a length and the roller part150may have a circumference such that roller part150rotates once to fully wind the display part DP along the outer peripheral surface of the roller part150. In other words, the length of the display part DP corresponds to a circumference of the roller part150in an embodiment. Such an arrangement is also preferable to prevent interference between the base plate155and the protrusions153P of the tape spring casing sides153S. In an embodiment, the protrusions153P prevent over rotation of the roller part150through contact with the base plate155. Therefore, the display part DP may more stably move downward or upward relative to the roller part150when the roller part150performs the winding or unwinding operation.

In the display device100according to embodiments of the present disclosure, the roller part150, which winds or unwinds the display part DP, and the motor151, which operates the tape spring170that moves the display part DP in the upward/downward direction, are disposed in the same space. In other words, the motor151is internal the tape spring casing153of the roller part150, and the tape spring170is positioned inside roller drums154coupled to the tape spring casing153to reduce the space occupied by the roller part150. Therefore, it is possible to minimize an operational space of the display device100.

In a display device in the related art, a motor is provided to operate a lifting part for moving a display part in an upward/downward direction, a roller part is provided to wind or unwind the display part, and the motor and the roller part are separately disposed. That is, when a shaft of the motor rotates, the lifting part moves in the upward/downward direction, such that the display part connected to the lifting part is wound around or unwound from the roller part. Therefore, in the display device in the related art, separate spaces in which the motor and the roller part are respectively disposed are required. For this reason, there are problems in that it is difficult to ensure spatial utilization of the display device, and an overall volume of the display device increases.

Therefore, in the display device100according to embodiments of the present disclosure, the tape spring161may be applied as a lifting part for moving the display part DP in the upward and/or downward direction, and the tape spring161may also be accommodated in the roller part150to reduce space. The display part DP is wound around or unwound from the outer peripheral surface150P of the roller part150that accommodates the motor151and is rotated by the motor151. Therefore, the motor151is configured to move the tape spring161in the upward and/or downward direction and is accommodated in the roller part150and rotated together with the roller part150, such that the motor151and the roller part150may be integrated. Therefore, in the display device100according to embodiments of the present disclosure, the roller part150, which winds or unwinds the display part DP, and the motor151, which operates the tape spring161that moves the display part DP in the upward and/or downward direction, are disposed in the same space. Therefore, it is possible to minimize an operational space for the display device100and improve the spatial utilization of the display device100.

FIG.11Ais a perspective view of a roller part of a display device1100according to an embodiment of the present disclosure.FIG.11Bis a cross-sectional view of the roller part of the display device1100according to the present disclosure. The display device1100illustrated inFIGS.11A and11Bmay be substantially identical in configuration to the display device100illustrated inFIGS.1A to10B, except as otherwise provided below. Therefore, repeated descriptions of the identical components will be omitted.

Referring toFIGS.11A and11B, the roller part150may further include a guide member GM.

In the display device1100according to embodiments of the present disclosure, the guide member GM is further disposed between the tape spring drum152and the tape spring casing153, such that the tape spring161may be more stably wound or unwound.

Specifically, the guide member GM may be disposed between the tape spring drum152and the tape spring casing153and configured to guide the tape spring161. The guide member GM may be additionally disposed on a part of the outer peripheral surface1520of the tape spring drum152and mitigate a rapid change in shape that occurs when the tape spring161, which is disposed between the tape spring drum152and the tape spring casing153, is unwound. In an embodiment, and referring toFIG.11B, an outer surface of the guide member GM is formed as a curved surface, and a curvature of the curved outer surface of the guide member GM may be different from a curvature of the outer peripheral surface1520of the tape spring drum152. Therefore, the guide member GM may assist with gradually forming the curved shape of the tape spring161when the tape spring161is unwound. Therefore, in the display device1100according to an embodiment of the present disclosure, the guide member GM is further disposed between the tape spring drum152and the tape spring casing153, such that the tape spring161may be more stably wound or unwound, and the display device1100may be more stably operated.

Additional features related to the disclosure herein are described in U.S. patent application Ser. No. 17/977,868 filed on Oct. 31, 2022 in the U.S. Patent Office, titled: Display Device, with a claim of priority to Korean Patent Application No. 10-2021-0193484 filed on Dec. 30, 2021, in the Korean Intellectual Property Office; the entire contents of which are incorporated herein by reference.

The example embodiments of the present disclosure can also be described and/or summarized as follows.

According to one or more embodiments of the present disclosure, a display device includes: a display including a display panel configured to display an image; a roller configured to wind or unwind the display; and a tape spring configured to move the display part in an upward direction or a downward direction in conjunction with the roller, wherein the roller includes a motor; a tape spring drum accommodating the motor and connected to the motor, a first end of the tape spring being fixed to the tape spring drum, and the tape spring drum configured to wind or unwind the tape spring; a tape spring casing accommodating the tape spring drum and the tape spring; and a plurality of roll drums connected to opposite sides of the motor.

The roller part may further comprise a tape spring guide connected to the tape spring casing, the tape spring guide configured to guide a winding or unwinding operation of the tape spring, the tape spring accommodated in the tape spring casing.

The display device may further comprise a printed circuit board connected to the display and configured to supply a signal to the display.

The roller part may further comprise a base plate connected to the plurality of roll drums, the base plate having a planar portion for supporting the printed circuit board, and wherein the printed circuit board may be disposed on the planar portion of the base plate.

The display has a length that rotates once along an outer peripheral surface of the roller in response to the display being wound.

The roller part may further comprise a guide member disposed between the tape spring drum and the tape spring casing, the guide member configured to guide the tape spring.

An outer surface of the guide member is a curved surface, and a curvature of the curved surface is different from a curvature of an outer peripheral surface of the tape spring drum.

The roller part may further comprise a spiral spring having an elastic force, wherein a first end of the spiral spring is connected to one of the plurality of roll drums and a second end of the spiral spring is connected to the tape spring drum.

The tape spring drum may comprise an extension portion extending from an inside of the tape spring casing to an outside of the tape spring casing, and the second end of the spiral spring is connected to the extension portion of the tape spring drum.

The tape spring is configured to accumulate elastic force in response to the display being wound.

The roller part may further comprise a plurality of first bearings disposed at two opposite sides of the tape spring drum, the plurality of first bearings configured to support the tape spring drum and enable rotation of the tape spring drum relative to the tape spring casing.

The roller part may further comprise a plurality of second bearings disposed at two opposite sides of each of the plurality of roll drums and configured to support two opposite sides of each of the roll drums and enable rotational motion of the plurality of roll drums relative to the tape spring casing.

The roller part may further comprise a motor fixture connected to the tape spring drum and configured to cover the motor disposed in the tape spring drum.

According to one or more embodiments of the present disclosure, a display device includes: a display configured to display an image; a tape spring coupled to the display; and a roller configured to wind or unwind the display and the tape spring, the roller including a motor, a tape spring drum accommodating the motor and connected to the motor, the tape spring drum configured to wind or unwind the tape spring, a tape spring casing accommodating the tape spring drum and the tape spring, and a plurality of roll drums connected to opposite sides of the motor.

The roller may further includes a spiral spring coupled to one of the plurality of roll drums and the tape spring drum, the spiral spring configured to accumulate elastic force in response to the display being wound about the roller.

The roller may further include a base plate coupled to a flat portion of the plurality of roll drums, the base plate having at least one planar surface.

The display device may further comprise a printed circuit board coupled to the display, the printed circuit board disposed on the at least one planar surface of the base plate.

The display may have a length that corresponds to a circumference of the roller.

According to one or more embodiments of the present disclosure, a display device includes: a roller configured to wind or unwind a display and a tape spring coupled to the display, the roller including a tape spring casing, a tape spring drum configured to wind or unwind the tape spring, at least a portion of the tape spring drum being internal to the tape spring casing, a motor connected to the tape spring drum, at least a portion of the motor being internal to the tape spring drum, and a roll drum connected to the motor.

The roller may further include a guide element having at least one curved surface configured to guide a curved surface of the tape spring.

The roller may further include a spiral spring coupled to the roll drum and the tape spring drum, the spiral spring configured to accumulate elastic force as a result of a difference in diameter between the roll drum and the tape spring drum.

The roller may have a flat portion and the display device may further comprise a printed circuit board coupled to the display, the printed circuit board disposed on the flat portion of the roller.

In one more embodiments of the present disclosure, a display device includes: a display configured to display an image; a tape spring coupled to the display; and a roller configured to wind or unwind the display and the tape spring, the roller including a motor, a tape spring drum accommodating the motor and connected to the motor, the tape spring drum configured to wind or unwind the tape spring, a tape spring casing accommodating the tape spring drum and the tape spring, and a plurality of roll drums connected to opposite sides of the motor.

The roller may further include a spiral spring coupled to one of the plurality of roll drums and the tape spring drum, the spiral spring configured to accumulate elastic force in response to the display being wound about the roller.

The roller may further include a base plate coupled to a flat portion of the plurality of roll drums, the base plate having at least one planar surface, the display device further comprising a printed circuit board coupled to the display, the printed circuit board disposed on the at least one planar surface of the base plate.

The display may have a length that corresponds to a circumference of the roller.

In one or more embodiments of the present disclosure, a display device includes: a roller configured to wind or unwind a display and a tape spring coupled to the display, the roller including a tape spring casing, a tape spring drum configured to wind or unwind the tape spring, at least a portion of the tape spring drum being internal to the tape spring casing, a motor connected to the tape spring drum, at least a portion of the motor being internal to the tape spring drum, and a roll drum connected to the motor.

The roller may further include a guide element having at least one curved surface configured to guide a curved surface of the tape spring.

The roller may further include a spiral spring coupled to the roll drum and the tape spring drum, the spiral spring configured to accumulate elastic force as a result of a difference in diameter between the roll drum and the tape spring drum.

The roller may have a flat portion, the display device further comprising a printed circuit board coupled to the display, the printed circuit board disposed on the flat portion of the roller.