Indication device

Abstract

To provide a display device with improved flatness of a folding area even after folding / unfolding operation for a long time in the display device.SOLUTION: A display device comprises: a panel assembly including a display panel including a first unfolding area, a second unfolding area, and a folding area between the first unfolding area and the second unfolding area, and a plate arranged under the display panel and including a slit pattern on the folding area; and a middle plate arranged under the plate. The middle plate includes a first middle plate portion on the first unfolding area, a second middle plate portion on the second unfolding area, and a vertical middle plate portion on the folding area.SELECTED DRAWING: Figure 19

Description

[Technical Field]

[0001] The present specification relates to a display device, and more particularly to a display device that can be folded and unfolded. [Background technology]

[0002] Display devices are becoming increasingly smaller to meet consumer purchasing needs. Many manufacturers are working on miniaturizing display devices because this improves design and portability and allows display devices to demonstrate their advanced technological capabilities.

[0003] In particular, recently, a display device that can be folded or, conversely, unfolded has been developed. The display device can be folded or unfolded based on a hinge device. The display device is applied to small display devices such as smartphones, and is also applied to medium-sized display devices such as tablet PCs and laptops. Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by this specification is to provide a display device in which the flatness of the folding region is improved even after a long period of folding / unfolding operations in the display device.

[0005] Another problem to be solved by the present specification is to provide a display device in which a middle plate protruding toward a display panel does not come into physical contact with the display panel, and therefore no additional stress is applied thereto.

[0006] Still another problem to be solved by the present specification is to provide a display device in which wrinkles in the display panel are improved.

[0007] Another problem to be solved by this specification is to provide a display device that can prevent the application of additional stress that may occur when the display panel bends, because the middle plate protruding toward the display panel supports the upper structure.

[0008] The problems of this specification are not limited to those described above, and other technical problems can be inferred from the following embodiments. [Means for solving the problem]

[0009] To solve the above problem, one embodiment of a display device includes a panel assembly including a display panel including a first unfolding area, a second unfolding area, and a folding area between the first unfolding area and the second unfolding area, and a plate disposed below the display panel and including a slit pattern on the folding area; and a middle plate disposed below the plate, wherein the middle plate includes a first middle plate portion on the first unfolding area, a second middle plate portion on the second unfolding area, and a vertical middle plate portion on the folding area.

[0010] Another embodiment of a display device for solving the above problem includes a panel assembly including a display panel including a first unfolding area, a second unfolding area, and a folding area between the first unfolding area and the second unfolding area, and a plate arranged below the display panel, and a middle plate arranged below the plate, wherein the distance between the middle plate and the plate in the folding area is shorter than the distance between the middle plate and the plate in the first unfolding area.

[0011] Specific details of other embodiments are included in the detailed description and drawings. [Effects of the Invention]

[0012] The display device according to the embodiment can improve the flatness of the folding region even when folding / unfolding operations are repeated for a long period of time.

[0013] In the display device according to the embodiment, the middle plate protruding toward the display panel does not come into physical contact with the display panel, so no additional stress is applied, thereby improving durability and lifespan.

[0014] The display device according to the embodiment can reduce wrinkles in the display panel.

[0015] The bonding layer of the display device according to the embodiment may slip during a folding operation. However, since the middle plate can support the upper structure when the display device is unfolded, the bonding layer can easily return to its original position after slipping.

[0016] However, the effects obtained in this specification are not limited to those described above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which this specification pertains from the following description. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 2 is a diagram illustrating an unfolded state of the display device according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing a folded state of the display device according to the first embodiment. [Figure 3] 1 is an exploded perspective view of a display device according to a first embodiment. [Figure 4] 1 is a cross-sectional view of a display device according to a first embodiment. [Figure 5] 5 is a schematic diagram showing how the middle plate, the plate, the display panel, and the cover member of the display device shown in FIG. 4 are fastened to a hinge assembly; FIG. [Figure 6]FIG. 2 is an exploded perspective view of the hinge assembly according to the first embodiment. [Figure 7] FIG. 1 is a perspective view of a hinge assembly according to a first embodiment. [Figure 8] FIG. 8 is an enlarged view of part A in FIG. 7. [Figure 9] FIG. 1 is a plan view of a hinge assembly according to a first embodiment. [Figure 10] FIG. 10 is a cross-sectional view taken along line AA' in FIG. [Figure 11] FIG. 10 is a perspective view showing the hinge assembly in an unfolded state. [Figure 12] FIG. 10 is a perspective view showing the hinge assembly in a folded state. [Figure 13] FIG. 10 is another perspective view showing the hinge assembly in an unfolded state. [Figure 14] FIG. 14 is an enlarged view of a part of FIG. 13. [Figure 15] 1 is a cutaway perspective view showing an unfolded state of a display device according to a first embodiment. FIG. [Figure 16] 1 is a cutaway perspective view showing a folded state of a display device according to a first embodiment. [Figure 17] 5 is a cross-sectional view showing the display device of the first embodiment in FIG. 4 in a folded state. [Figure 18] FIG. 4 is a cross-sectional view showing a modified example of the display device according to the first embodiment. [Figure 19] FIG. 10 is a cross-sectional view of a display device according to a second embodiment. [Figure 20] FIG. 10 is a cross-sectional view showing a folded state of the display device according to the second embodiment. [Figure 21] FIG. 10 is a cross-sectional view showing a modified example of the display device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an embodiment will be described with reference to the drawings.

[0019] The same reference numerals refer to the same elements. In the drawings, the thickness, ratio, and dimensions of elements may be exaggerated for the purpose of effectively explaining the technical content. The scales of elements shown in the drawings may be different from the actual scales for the convenience of explanation, and therefore are not limited to the scales shown in the drawings.

[0020] In this specification, when a component (or region, layer, portion, etc.) is referred to as being "on," "connected to," or "coupled" to another component, it means that it may be directly connected / coupled to the other component, or that a third component may be disposed therebetween.

[0021] "And / or" includes all combinations of one or more that the associated constructs can define.

[0022] Terms such as "first," "second," etc. may be used to describe various components, but the components are not limited by these terms. These terms are used only to distinguish one component from another. For example, a first component may be referred to as a "second component," and similarly, a second component may be referred to as a "first component" without departing from the scope of the present embodiment. A singular expression includes a plural expression unless the context clearly dictates otherwise.

[0023] Terms such as "below," "beneath," "on," and "above" are used to describe the relative relationships of features shown in the drawings. These terms are relative and are described with reference to the orientation shown in the drawings. For example, unless "immediately" or "directly" is used, one or more other parts may be located between two parts. Spatially relative terms such as "below," "beneath," "lower," "above," and "upper" can be used to easily describe the relationship of one element or component to another element or component, as shown. Spatially relative terms should be understood to include different orientations of elements during use or operation, in addition to the orientation shown. For example, if elements shown are inverted, an element described as "below" or "beneath" another element may be positioned "above" the other element. Thus, the exemplary term "below" can encompass both an orientation of below and an orientation of above.

[0024] Terms such as "comprise" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof stated in the specification, and should be understood as not precluding the possible presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0025] The features of the various embodiments of this specification may be partially or wholly combined or combined with each other, and may be technically interlocked and driven in various ways, and each embodiment may be implemented independently of the other or may be implemented together in association with each other.

[0026] The display device of the present specification will be discussed below with reference to the accompanying drawings and embodiments.

[0027] Fig. 1 is a diagram showing an unfolded state of the display device according to the first embodiment, and Fig. 2 is a diagram showing a folded state of the display device according to the first embodiment.

[0028] 1 shows the front, top, bottom, right, left, and back sides of the unfolded display device 10. FIG. 2 shows the front, top, bottom, right, left, and back sides of the folded display device 10.

[0029] Referring to FIG. 1, the display device 10 may include a display panel PNL including a display area DA including a plurality of pixels. A non-display area may be disposed around the display area DA. The non-display area may not include pixels and may be a bezel area. The display panel PNL may include a folding area FA, a first unfolding area NFA1 located on one side of the folding area FA, and a second unfolding area NFA2 located on the other side of the folding area FA. Portions of the first unfolding area NFA1, folding area FA, and second unfolding area NFA2 of the display panel PNL that correspond to the display area DA may display an image.

[0030] The display device 10 includes a hinge assembly 200 that can rotate about a folding axis A1. The hinge assembly 200 may not be substantially visible from the front or rear of the display device 10 in the unfolded state because the hinge assembly 200 is disposed on the rear of the display device 10 and is covered by the cover frame CF.

[0031] The hinge assembly 200 may have a shape that is elongated along the folding axis A1. The hinge assembly 200 may be disposed within a folding area FA. The folding area FA is an area where the display panel PNL is folded by the hinge assembly 200. The first unfolding area NFA1 and the second unfolding area NFA2 are areas symmetrical to each other with respect to the folding area FA. The first unfolding area NFA1 is an area located on one side of the folding axis A1, and the second unfolding area NFA2 is an area located on the other side of the folding axis A1.

[0032] A top frame TF may be disposed on the front surface of the display device 10. The top frame TF may be disposed to cover the edge of the display panel PNL. The front surface of the display device 10 refers to the surface on which an image is displayed by the display panel PNL. Since the display device 10 is folded based on the folding axis A1, the top frame TF may include two top frames TF1 and TF2 that are physically separated from each other. The top frame TF includes a first top frame TF1 disposed on one side of the folding axis A1 and a second top frame TF2 disposed on the other side. The height from the bottom surface of the display device 10 to the top frame TF may be higher than or substantially the same as the height to the display panel PNL. Therefore, the display panel PNL may not be visible when viewed from the side. The first top frame TF1 and the second top frame TF2 are as shown in FIG. 3.

[0033] The sides and rear of the display device 10 may be covered by a cover frame CF. The rear of the display device 10 is the side opposite the front, and the side refers to the surface between the front and rear. Since the display device 10 is folded based on the folding axis A1, the cover frame CF may include two cover frames CF1 and CF2 that are physically separated from each other. The cover frame CF includes a first cover frame CF1 disposed on one side of the folding axis A1 and a second cover frame CF2 disposed on the other side. The first cover frame CF1 and the second cover frame CF2 are as shown in FIG. 3.

[0034] The hinge assembly 200 is disposed near the rear surface of the display device 10 and is disposed along the folding axis A1. The hinge assembly 200 may be disposed so as to be covered by the cover frames CF1 and CF2 in the unfolded state. In the unfolded state, the hinge assembly 200 of the display device 10 may be disposed so as not to be visible from the outside. Alternatively, in the unfolded state, the hinge assembly 200 of the display device 10 may be disposed so as to be only minimally visible from the outside.

[0035] Although not shown, a camera module capable of capturing images may be disposed on the front, back, and / or side of the display device 10. In addition, buttons for controlling functions of the display device 10 and components for performing functions may be disposed on the front, back, and / or side of the display device. For example, a volume button, a power button, a mode switching button, a speaker, a microphone, an antenna, a flash, etc. may be disposed.

[0036] Although not shown, the display device 10 may include a sensor for sensing an operating state or an external environment. For example, the display device 10 may include a gesture sensor, a grip sensor, a color sensor, an infrared sensor, an illuminance sensor, an ultrasonic sensor, an iris recognition sensor, a distance detection sensor, a LiDAR sensor, etc.

[0037] Although not shown, the display device 10 may include a connector for receiving signals from an external device, such as a charging connector, a USB connector, or an earphone jack connector.

[0038] 2, when the display device 10 is folded, the display panel PNL is folded such that the first unfolding area NFA1 and the second unfolding area NFA2 face each other with respect to the folding axis A1. The hinge assembly 200 may be exposed to the outside as the cover frames CF1 and CF2 rotate and fold.

[0039] In the folded state, the display panel PNL is not visible from the outside, and only the cover frames CF1, CF2 and the hinge assembly 200 of the display device 10 are visible from the outside.

[0040] According to various embodiments, the cover frames CF1 and CF2 are not limited to the shapes and combinations shown in FIGS. 1 and 2 and may be embodied with other shapes and combinations of parts. According to one embodiment, the first cover frame CF1 and the second cover frame CF2 may be disposed on both sides of the folding axis A1 and have a shape that is generally symmetrical with respect to the folding axis A1. According to one embodiment, the first cover frame CF1 and the second cover frame CF2 may be disposed asymmetrically with respect to the folding axis A1 and have an asymmetric shape. According to one embodiment, the angle and distance formed between the first cover frame CF1 and the second cover frame CF2 may vary depending on whether the display device 10 is in a folded state, an unfolded state, or an intermediate state. According to one embodiment, each of the first cover frame CF1 and the second cover frame CF2 may be physically separated into a frame that covers only the back side of the display device 10 and a frame that covers only the side side of the display device 10.

[0041] According to various embodiments, the first cover frame CF1 and the second cover frame CF2 may be structurally coupled to form an internal accommodating space, in which the hinge assembly 200 and the display panel PNL may be accommodated.

[0042] According to various embodiments, the internal storage space may accommodate components for driving the display device 10. For example, the internal storage space may accommodate a battery, a control printed circuit board, a flat cable, a flexible printed circuit board, and the like.

[0043] According to various embodiments, the size of the portion of the hinge assembly 200 exposed to the outside may vary depending on the folding angle of the display device 10. For example, when the display device 10 is in a folded state, a large portion of the hinge assembly 200 may be exposed between the first cover frame CF1 and the second cover frame CF2. When the display device 10 is in an unfolded state, the hinge assembly 200 may be substantially covered by the first cover frame CF1 and the second cover frame CF2. When the display device 10 is in an intermediate state between the folded state and the unfolded state, a relatively small portion of the hinge assembly 200 may be exposed between the first cover frame CF1 and the second cover frame CF2.

[0044] According to various embodiments, when the display device 10 is in an unfolded state, the angle formed between the first cover frame CF1 and the second cover frame CF2 may be 180 degrees. Accordingly, the angle formed between the first unfolding area NFA1 and the second unfolding area NFA2 may be 180 degrees. Therefore, the display panel PNL can be in a completely flat state.

[0045] According to various embodiments, when the display device 10 is in an intermediate state between the folded state and the unfolded state, folding may be stopped at that folding angle, which can be called a free stop.

[0046] According to various embodiments, the cover frame CF and the top frame TF may be formed of glass or polymer. The cover frame CF and the top frame TF may be transparent or opaque. For example, the cover frame CF and the top frame TF may be formed of coated or tinted glass, ceramic, polymer, aluminum, stainless steel, magnesium, or combinations thereof.

[0047] Fig. 3 is an exploded perspective view of the display device according to the first embodiment. Fig. 4 is a cross-sectional view of the display device according to the first embodiment. Fig. 5 is a schematic view showing that the middle plate, plate, display panel, and cover member of the display device according to Fig. 4 are fastened to a hinge assembly.

[0048] 3 to 5, in this specification, the direction along the folding axis A1 along which the display device 10 is folded is defined as an axial direction AD. The direction from the first unfolding area NFA1 of the display device 10 through the folding area FA to the second unfolding area NFA2 is defined as a lateral direction SD. The direction in which the display panel PNL of the display device 10 faces is defined as an upper direction UD. The direction opposite to the upper direction UD is defined as a lower direction BD.

[0049] A top frame TF is disposed at the topmost part of the display device 10 in the upward direction UD. The top frame TF includes a first top frame TF1 disposed on one side of the folding axis A1 and a second top frame TF2 disposed on the other side. The top frame TF is disposed to cover the edge of the display panel PNL. The top frame TF can protect the display panel PNL from external impacts. The top frame TF can form a bezel of the display device 10.

[0050] A cover member CG may be disposed under the top frame TF. The cover member CG may be disposed over the display panel PNL. The cover member CG may be made of a glass material such as glass or quartz. However, the cover member CG is not limited thereto, and may be made of a plastic material.

[0051] The cover member CG is disposed on top of the display panel 100, thereby serving to protect the components disposed below the cover member CG from the outside. Meanwhile, since the display device 10 functions as a display device, the cover member CG must be flexible. Therefore, the modulus of the cover member CG is preferably 70 GPa or less, and the thickness is preferably approximately 100 μm or less. However, if the cover member CG is too thin, it will not be able to fulfill its role of protecting the components below the cover member CG. Therefore, the cover member CG preferably has a thickness of at least approximately 20 μm. The cover member CG may be a cover layer formed by chemical strengthening.

[0052] Meanwhile, the cover member CG serves to protect the components disposed below the cover member CG from the outside, but since it is made of a glass material as described above, there is a possibility that the cover member CG may be broken by an external force, generating glass fragments, which may scatter outside the display device 10. In order to prevent scattering of glass fragments due to the breakage of the cover member CG, a film layer, a hard coat layer, etc. may be further disposed on the cover member CG.

[0053] A panel assembly PNLA is disposed on the lower part of the cover member CG. The panel assembly PNLA includes a display panel PNL and a plate PLT. The display panel PNL may include a flexible substrate, a circuit element layer including transistors disposed on the flexible substrate, a light-emitting layer including light-emitting elements disposed on the circuit element layer, a sealing layer disposed on the light-emitting layer, a touch layer disposed on or within the sealing layer, a polarizer for reducing luminous reflectance from the front surface, and a cover glass disposed on the touch layer. The display panel PNL may include a first unfolding area NFA1, a folding area FA, and a second unfolding area NFA2.

[0054] The plate PLT may include various plates disposed below the display panel PNL to support the display panel PNL. For example, the one or more plates may include a back plate for supporting the display panel PNL, a top plate disposed below the back plate and made of SUS material, a bottom plate disposed below the top plate and made of SUS material with a pattern formed on a folding portion, a heat dissipation sheet having a heat dissipation function, a middle plate for covering a plane that is not flattened by various configurations of the hinge assembly, etc.

[0055] As shown in FIGS. 3 to 5, a slit pattern PTN may be formed in the plate PLT. The slit pattern PTN may be formed at a position corresponding to the folding area FA of the display panel PNL. The slit pattern PTN may be a slit-shaped etching portion formed in the plate PLT. The plate PLT is made of a metal such as SUS, but due to the strength of metal, problems may occur when folding or unfolding the plate PLT. The slit pattern PTN can complement the flexibility of the plate PLT. The plate PLT shown in FIG. 3 may be a bottom plate.

[0056] A middle plate MST is disposed below the panel assembly PNLA. The middle plate MST supports components disposed further in the upward direction UD. The hinge assembly 200 and the cover frame CF are disposed in the downward direction BD of the middle plate MST, and their upper surfaces may be uneven. The middle plate MST can flatten the uneven lower surfaces. The middle plate MST may be formed of a material such as plastic, polyimide, or metal to increase the rigidity of the display device 10. For example, the middle plate MST may include, but is not limited to, aluminum or SUS. The middle plate MST may be a pair of middle plates MST.

[0057] The middle plate MST may include a first middle plate portion MSTH1 disposed in the first unfolding area NFA1 and a second middle plate portion MSTH2 disposed in the second unfolding area NFA2.

[0058] The hinge assembly 200 is disposed below the panel assembly PNLA. The hinge assembly 200 is disposed below the folding area FA. The hinge assembly 200 may have an elongated shape along the axial direction AD. The hinge assembly 200 can perform a folding movement in which one side rotates to the other side based on the folding axis A1. The hinge assembly 200 will be described in detail below with reference to FIG. 5, etc.

[0059] A cover frame CF is disposed under the hinge assembly 200. An upper surface of the cover frame CF may be formed with a receiving groove in which a portion of the hinge assembly 200 can be seated. The cover frame CF includes a first cover frame CF1 disposed on one side of the folding axis A1 and a second cover frame CF2 disposed on the other side. The cover frame CF may be a housing that defines the sides and rear of the display device 10. The cover frame CF can protect the display device 10 from external impacts. The cover frame CF can be coupled to the hinge assembly 200. The display device 10 can be folded and unfolded by rotating the cover frames CF1 and CF2.

[0060] Between adjacent members MST, PLT, PNL, CG, connecting members BM1, BM2, BM3 may be further disposed. The first connecting member BM1 may connect the middle plate members MSTH1, MSTH2 and the upper plate PLT in each unfolding area NFA1, NFA2, the second connecting member BM2 may connect the plates PLT, PTN and the upper display panel PNL, and the third connecting member BM3 may connect the display panel PNL and the cover member CG.

[0061] 5, the plate PLT, the middle plate portion MSTH1, and the middle plate portion MSTH2 coupled to each other can be mounted (fixed) to the cover frames CF1 and CF2. The hinge assemblies 200 disposed on the cover frames CF1 and CF2 enable the display device 10 to perform folding and unfolding operations.

[0062] The specific structure and function of the hinge assembly 200 including the hinge support 250 will be described in detail below with reference to FIGS.

[0063] FIG. 6 is an exploded perspective view of the hinge assembly according to the first embodiment. FIG. 7 is a perspective view of the hinge assembly according to the first embodiment. FIG. 8 is an enlarged view of portion A in FIG. 7. FIG. 9 is a plan view of the hinge assembly according to the first embodiment. FIG. 10 is a cross-sectional view taken along line A-A' in FIG. 9. In FIG. 6, in order to show the internal configuration, the gear arm 240 is not shown in the upper left side, and the hinge arm 230 is not shown in the upper right side. In FIG. 8, the second hinge arm 230b is not shown in order to show the pair of bevel gears 241a, 241b.

[0064] 6 to 10, the hinge assembly 200 according to the first embodiment may be composed of a hinge housing 210, a pair of hinge arms 230, and an inner frame 220.

[0065] Although not shown, the hinge assembly 200 of the first embodiment may further include, but is not limited to, a hinge arm upper cover and a hinge arm lower cover that are fastened to the upper and lower portions of the hinge arm 230, respectively. The hinge assembly 200 may include a pair of hinge arms 230 on one side, and the pair of hinge arms 230 may be rotatably connected to each other. That is, the hinge arm 230 may be configured with, but is not limited to, a first hinge arm 230a and a second hinge arm 230b that have a symmetrical structure. The first hinge arm 230a and the second hinge arm 230b may have a symmetrical structure to each other.

[0066] The hinge arm 230 according to the first embodiment is characterized by having a two-axis folding (rotating) structure. That is, if a folding hinge is implemented using a four-axis gear, it may not be possible to manufacture a thin set, or the gears may need to be miniaturized to achieve a thin design, which may result in durability issues. Therefore, the present invention is characterized by a display device (see 10 in FIG. 1) with a new hinge structure that forms a folding trajectory (shown by the dotted line in FIG. 10) based on a two-axis rotation structure. That is, the display device according to the first embodiment is characterized by a display device (see 10 in FIG. 1) with a two-axis folding hinge structure that can fold in an inner direction. Furthermore, the first embodiment is characterized by a display device 10 with a new hinge structure that includes two bevel gears 241 and a link slider structure for inter-axis synchronization (sync) during two-axis rotation. The hinge arm 230 is a two-axis folding lever, also known as a lever wing.

[0067] The bevel gear 241 may be a gear for synchronizing (sinking) the two-axis folding hinge arm 230. Therefore, the bevel gear 241 is also called a sink gear.

[0068] The bevel gear 241 may include a first bevel gear 241a coupled to the first hinge arm 230a and a second bevel gear 241b coupled to the second hinge arm 230b.

[0069] The first bevel gear 241a and the second bevel gear 241b may have a virtual axis different from the rotation axis R_AXIS, which is an actual axis. That is, the first bevel gear 241a and the second bevel gear 241b may have a virtual axis that is substantially perpendicular to the rotation axis R_AXIS.

[0070] The first tooth form portion and the second tooth form portion formed on the first bevel gear 241a and the second bevel gear 241b may be formed only on a part of the circumference, respectively, but are not limited to this.

[0071] The first bevel gear 241a and the second bevel gear 241b may be arranged to mesh with each other. However, without being limited thereto, the first bevel gear 241a and the second bevel gear 241b may be configured to mesh with the first rotary gear and the second rotary gear, respectively, and the first rotary gear and the second rotary gear may be configured to mesh with each other.

[0072] The left and right sync can be maintained through two bevel gears 241, namely, a first bevel gear 241a and a second bevel gear 241b.

[0073] The first bevel gear 241a and the second bevel gear 241b may include second idle gears that mesh with the first idle gears of the first hinge arm 230a and the second hinge arm 230b, respectively, to convert and transmit the rotation of the first hinge arm 230a and the second hinge arm 230b in a vertical direction.

[0074] At this time, the first idle gear and the second idle gear are arranged in a substantially vertical direction, and can convert rotation in a vertical direction. That is, the first bevel gear 241a and the second bevel gear 241b are rotatably fastened to the first idle gears of the first hinge arm 230a and the second hinge arm 230b through the second idle gears, respectively, while the first hinge arm 230a and the second hinge arm 230b are slidably fastened to the first gear arm 240a and the second gear arm 240b, respectively, and can perform folding and unfolding operations of the display device 10 while maintaining left and right synchronization.

[0075] The first gear arm 240a and the second gear arm 240b are provided at their ends with slide pins 242 that protrude toward the first hinge arm 230a and the second hinge arm 230b, respectively. A slide space 239 in which the slide pins 242 can move may be provided in the protrusions 238 of the first hinge arm 230a and the second hinge arm 230b that face the first gear arm 240a and the second gear arm 240b. Therefore, during the folding or unfolding operation of the display device 10, the slide pins 242 move within the slide space 239, and the first gear arm 240a and the second gear arm 240b can rotate in conjunction with the rotation of the first hinge arm 230a and the second hinge arm 230b. This will be described in detail below with reference to FIGS. 13 to 16.

[0076] Meanwhile, the gear arm 240 can be rotatably fastened to the shaft 233 .

[0077] The gear arm 240 is a two-axis folding detent, also called a lever detent.

[0078] That is, the gear arm 240 may include a first gear arm 240a and a second gear arm 240b, and the first hinge arm 230a and the second hinge arm 230b may be coupled to the first gear arm 240a and the second gear arm 240b, respectively, so as to be interlocked with each other.

[0079] The gear arm 240 may have a link structure connected to the two-axis hinge arm 230. That is, the first gear arm 240a and the second gear arm 240b may be connected to the first hinge arm 230a and the second hinge arm 230b, respectively. Therefore, during the folding or unfolding operation of the display device 10, the first hinge arm 230a and the second hinge arm 230b may rotate together due to the rotation of the first gear arm 240a and the second gear arm 240b, and left and right synchronization may be maintained by the first bevel gear 241a and the second bevel gear 241b connected to the first hinge arm 230a and the second hinge arm 230b, respectively.

[0080] In this manner, the first hinge arm 230a and the second hinge arm 230b can be linked to the first gear arm 240a and the second gear arm 240b, respectively.

[0081] The shaft 233 can form a frame for mounting and assembling the cam 245 .

[0082] A compression spring 260 may be provided on the outer surface of the shaft 233 between the gear arm 240 and the cam 245 to generate friction force for the cam 245 .

[0083] Gear arm 240 fastened to the outer surface of shaft 233 may be provided with a second detent 246 for maintaining the folding and unfolding angles of hinge arm 230 and gear arm 240 together with a plurality of cams 245. Therefore, cam 245 may be a configuration for torque for folding and unfolding hinge arm 230. Cam 245 is also called a slide cam.

[0084] Meanwhile, a predetermined hinge housing 210 that houses the inner frame 220, the hinge arm 230, and the gear arm 240 may be provided at the bottom of the hinge assembly 200.

[0085] The hinge housing 210 is an exterior cover of the hinge assembly 200, and has a predetermined length with a space provided inside to accommodate the inner frame 220, the hinge arm 230, and the gear arm 240. The hinge housing 210 is also called a hinge cover.

[0086] The inner frame 220 may be a frame that fixes the inside of the hinge assembly 200. The inner frame 220 may be provided with a plurality of fastening grooves (not shown) and through-grooves (not shown). The inner frame 220 is an exterior cover that houses the pair of first and second bevel gears 241a and 241b, and is also called a housing cover.

[0087] In addition, the hinge housing 210 is formed with a fixing member 211 that faces the fastening groove of the inner frame 220, and a fixing groove (or fixing hole) 212 is formed in the fixing member 211, so that the fixing member 211 can be fastened to the fastening groove by a fastening member such as a screw.

[0088] The hinge housing 210 has a predetermined size, and can accommodate the inner frame 220, the hinge arm 230, and the gear arm 240 within the space of the hinge housing 210.

[0089] On the other hand, the distance between the rotation centers of the pair of shafts 233 may be set to be greater than the distance D between the rotation axes R_AXIS, which are the rotation centers of the pair of hinge arms 230.

[0090] In this case, a pair of imaginary axes passing through the centers of the pair of shafts 233 may serve as central axes for connecting components constituting the hinge housing 210. The imaginary axes may be provided in pairs, and each may correspond to the first cover 110 and the second cover 120.

[0091] There may be an axis height H between the folding portion where the first hinge arm 230a and the second hinge arm 230b contact the display panel 180 and the rotation axis R_AXIS, but this is not limiting.

[0092] Meanwhile, as described above, the first embodiment is characterized in that the "T"-shaped hinge support 250 is disposed between the first gear arm 240a and the second gear arm 240b of the hinge assembly 200. The up / down hinge support 250 ensures a relief structure for realizing the curvature of the display panel 180 when folding, and also supports the first gear arm 240a and the second gear arm 240b, thereby improving impact resistance.

[0093] The hinge support 250 may be disposed within the inner frame 220 between the first gear arm 240a and the second gear arm 240b along the length of the inner frame 220.

[0094] The hinge support 250 may have a "T" shape with its upper end protruding in a direction perpendicular to its length.

[0095] The hinge support 250 may have an empty space inside, but is not limited to this.

[0096] On the other hand, as described above, the present invention is characterized by having not only two bevel gears 241a, 241b but also a link slider structure for inter-axial synchronization during two-axial rotation, which will be described in detail with reference to Figures 10 to 16.

[0097] Fig. 11 is a perspective view showing the hinge assembly in an unfolded state. Fig. 12 is a perspective view showing the hinge assembly in a folded state. Fig. 13 is another perspective view showing the hinge assembly in an unfolded state. Fig. 14 is an enlarged view of a portion of Fig. 13. Fig. 15 is a cutaway perspective view showing the display device according to the first embodiment in an unfolded state. Fig. 16 is a cutaway perspective view showing the display device according to the first embodiment in a folded state.

[0098] 11, 12, 13 and 14 show part of the structure of the hinge assembly with the hinge housing removed for the sake of convenience of explanation.

[0099] 15 and 16 show particular unfolded and folded states of the display device, respectively, with the display panel and bezel cover omitted for ease of explanation.

[0100] 11 and 12 to 15 and 16, a set housing 110 may be disposed below the hinge assembly and set frames 150, 160.

[0101] The set frames 150, 160 may include, but are not limited to, a first support plate 150 on the left side and a second support plate 160 on the right side, and a first frame on the left side and a second frame on the right side.

[0102] The first support plate 150 and the second support plate 160 are provided separately so as to be able to fold independently of each other, and a hinge assembly may be provided between them.

[0103] The display device according to the first embodiment may be implemented using an in-folding method in which the screen is disposed inside when folded.

[0104] In addition, the first and second support plates 150 and 160 of the first embodiment may be disposed in one and the other side areas where folding and unfolding of the display device is performed.

[0105] The hinge assembly may be comprised of a hinge housing 210 , first and second hinge arms 230 a , 230 b , and an inner frame 220 .

[0106] Furthermore, the hinge assembly of the first embodiment may further include a hinge arm upper cover and a hinge arm lower cover fastened to the upper and lower portions of the first and second hinge arms 230a, 230b, but is not limited thereto.

[0107] The hinge assembly includes a pair of hinge arms 230a, 230b, and the hinge arms 230a, 230b may include a first hinge arm 230a and a second hinge arm 230b that are symmetrical to each other.

[0108] The first hinge arm 230a and the second hinge arm 230b according to the first embodiment are characterized by having a two-axis folding (rotating) structure.

[0109] At this time, the first hinge arm 230a and the second hinge arm 230b can fold (rotate) along the folding trajectory of the housing cover rail 235 (see the arrows in FIG. 12).

[0110] That is, a pair of guide pins 234 protruding toward the first and second hinge arms 230a and 230b on the inside may be provided at the upper end of the inner frame 220, and a pair of housing cover rails 235 between which the pair of guide pins 234 are sandwiched may be provided on the first and second hinge arms 230a and 230b facing the pair of guide pins 234, but this is not limited thereto. Therefore, the first and second hinge arms 230a and 230b can fold (rotate) along the folding trajectory of the housing cover rails 235 while being guided by the pair of guide pins 234.

[0111] The first embodiment is characterized by having two bevel gears 241a and 241b and a link slider structure for inter-axis synchronization during biaxial rotation. The thickness of the display device can be minimized by using two bevel gears instead of four general gears. In other words, if the left and right syncs are adjusted using four general gears, the thickness of the hinge assembly may increase due to the thickness of the four vertically arranged gears. Therefore, the first embodiment adjusts the left and right syncs using two bevel gears 241a and 241b, thereby reducing the thickness and weight of the hinge assembly. Furthermore, folding with a smaller R value than conventional folding is possible.

[0112] Specifically, the bevel gear 241 may include a first bevel gear 241a coupled to the first hinge arm 230a and a second bevel gear 241b coupled to the second hinge arm 230b.

[0113] The first bevel gear 241a and the second bevel gear 241b may have a virtual axis different from the rotation axis R_AXIS, which is an actual axis. That is, the first bevel gear 241a and the second bevel gear 241b may have a virtual axis that is substantially perpendicular to the rotation axis R_AXIS.

[0114] The first tooth form portion and the second tooth form portion formed on the first bevel gear 241a and the second bevel gear 241b may be formed only partially with respect to the circumference, but are not limited to this.

[0115] The first bevel gear 241a and the second bevel gear 241b may be arranged to mesh with each other. However, without being limited thereto, the first bevel gear 241a and the second bevel gear 241b may be configured to mesh with the first rotary gear and the second rotary gear, respectively, and the first rotary gear and the second rotary gear may be configured to mesh with each other.

[0116] The first bevel gear 241a and the second bevel gear 241b may include second idle gears 232b that mesh with the first idle gears 232a of the first hinge arm 230a and the second hinge arm 230b, respectively, to convert and transmit the rotation of the first hinge arm 230a and the second hinge arm 230b in a vertical direction (see Figures 13 and 14).

[0117] At this time, the first idle gear 232a and the second idle gear 232b are arranged substantially perpendicular to each other, and can convert rotation in a perpendicular direction. That is, the first bevel gear 241a and the second bevel gear 241b are rotatably connected to the first idle gear 232a of the first hinge arm 230a and the second hinge arm 230b via the second idle gear 232b, respectively, and the first hinge arm 230a and the second hinge arm 230b are slidably connected to the first gear arm 240a and the second gear arm 240b, respectively, and a left-right sync is maintained to perform folding and unfolding operations of the display device.

[0118] That is, when the first hinge arm 230a and the second hinge arm 230b are folded / unfolded in the vertical direction, the first bevel gear 241a and the second bevel gear 241b rotate in the horizontal direction to adjust the sink.

[0119] Meanwhile, the rotation axis R_AXIS of the first hinge arm 230a and the second hinge arm 230b may be different from a pair of imaginary axes B passing through the centers of the pair of shafts 233. That is, the rotation axis R_AXIS along which the first hinge arm 230a and the second hinge arm 230b fold / unfold and the imaginary axis B along which the first gear arm 240a and the second gear arm 240b fold / unfold do not coincide, and they can be linked to each other by being connected by a link slide structure.

[0120] Therefore, the imaginary axis B about which the first gear arm 240a and the second gear arm 240b fold / unfold is the central axis of the shaft 233, and the rotation axis R_AXIS about which the first hinge arm 230a and the second hinge arm 230b fold / unfold is the central axis of the housing cover rail 235. The two different folding / unfolding axes may be connected by a link slide structure to interlock with each other.

[0121] That is, the first embodiment is characterized in that two bevel gears, a first bevel gear 241a and a second bevel gear 241b, are provided for inter-axial synchronization during two-axis rotation, and the first gear arm 240a and the second gear arm 240b are slidably fastened to the first hinge arm 230a and the second hinge arm 230b, respectively.

[0122] That is, the first gear arm 240a and the second gear arm 240b may have slide pins 242 protruding toward the first hinge arm 230a and the second hinge arm 230b at their ends, respectively, and a slide space 239 in which the slide pin 242 can move may be provided in the first hinge arm 230a and the second hinge arm 230b facing the first gear arm 240a and the second gear arm 240b. Therefore, when the display device is folded or unfolded, the slide pin 242 moves within the slide space 239, and the first gear arm 240a and the second gear arm 240b can rotate (or fold / unfold) in conjunction with the rotation (or folding / unfolding) of the first hinge arm 230a and the second hinge arm 230b. In this way, the two-axis hinge operation can be synchronized through the two first bevel gears 241a and second bevel gears 241b and the link slider structure.

[0123] In this case, the slide space 239 may be provided within the side protrusions 238 of the first hinge arm 230a and the second hinge arm 230b, but is not limited to this. Meanwhile, in order to maintain a specific folding angle of the display device during folding and unfolding operations of the display device (see 10 in FIG. 1), a holding force is realized using frictional force between components constituting the hinge.

[0124] That is, the hinge assembly is disposed at a portion of the display device where folding and unfolding are performed, and can facilitate the folding and unfolding of the display device, and can provide a holding force to maintain the display device folded at a specific angle.

[0125] As described above, the display panel may be disposed on one surface of the first support plate 150 and the second support plate 160. The display panel may be one of various display panels such as an organic light-emitting display panel, a liquid crystal display panel, etc. The display panel may also be flexible so that it can be folded and unfolded in accordance with the folding and unfolding of the display device.

[0126] The display device may be folded such that the first support plate 150 and the second support plate 160 form a specific folding angle. That is, although FIG. 15 shows the first support plate 150 and the second support plate 160 fully unfolded, for example, at an angle of 180°, the display device may also be folded at a specific angle. That is, while FIG. 16 shows the first support plate 150 and the second support plate 160 folded, for example, at an angle of 90°, the display device may be folded at a specific angle. In this case, the display panel disposed on the first support plate 150 and the second support plate 160 may also be folded along with the folding of the first support plate 150 and the second support plate 160.

[0127] The display device may be folded at a specific angle as desired by the user, or may be completely folded or unfolded as desired by the user. The display device may be inner-folding (or in-folding), where the display panel is folded or unfolded on the inside, or out-folding, where the display panel is folded or unfolded on the outside.

[0128] The display device can maintain a specific folding angle due to the holding force provided by the hinge assembly. In other words, the first support plate 150 and the second support plate 160 can be fixed in a state in which a specific folding angle is maintained by the hinge assembly. Therefore, the display device can be folded at a specific angle as intended by the user, and can be maintained in the folded state at the specific angle due to the holding force of the hinge assembly.

[0129] In particular, the present invention is characterized in that a specific folding angle of the display device can be maintained by implementing a holding torque and free stop function by applying a cam 245 structure including a compression spring 260.

[0130] Fig. 17 is a cross-sectional view showing a folded state of the display device according to the first embodiment shown in Fig. 4. Fig. 18 is a cross-sectional view showing a modified example of the display device according to the first embodiment.

[0131] 17, the display panel PNL, the cover member CG, the plate PLT, and the middle plate MST may be folded based on a folding area FA. The first middle plate part MSTH1 and the second middle plate part MSTH2 may overlap each other in the thickness direction. The slit pattern PTN may be disposed in the folding area FA.

[0132] In the unfolded state of the display device 10, the folding area FA has a flat shape as shown in FIG. 4, but in the folded state, the folding area FA may be folded and curved as shown in FIG. When the display device 10 repeats folding / unfolding operations over a long period of time, deformation may occur in the folding region FA, which is subject to large deformation. When the unfolding operation is repeated, the folding area FA may bend downward as shown in FIG. 18. More specifically, when the folding area FA is repeatedly folded and unfolded, it undergoes significant deformation, which may cause the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA to bend downward and not return to their original state. Even if the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA are restored, the restoration time may be longer than the predetermined time. In this case, the bent shape (or wrinkled shape) may be visible from the outside, which may cause display defects. Because there is no other support member below the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA, the bent shape (or wrinkled shape) may become more severe over time.

[0133] The display device according to the second embodiment described below is introduced to solve the problem of bending of the folding area FA of the display device according to the first embodiment.

[0134] Fig. 19 is a cross-sectional view of a display device according to a second embodiment. Fig. 20 is a cross-sectional view showing a folded state of the display device according to the second embodiment. Fig. 21 is a cross-sectional view showing a modified example of the display device according to the second embodiment.

[0135] 19 to 21, the middle plate MST_1 of the display device 11 according to the second embodiment differs from the display device 10 according to FIG. 4 in that it can also be arranged in the folding area FA.

[0136] More specifically, the middle plate MST_1 may protrude upward from the folding region FA toward the upper members PNL and PTN. The middle plate MST_1 may further include a vertical middle plate protruding upward from the folding region FA toward the upper members PNL and PTN. The middle plate MST_1 may be formed by etching. However, the middle plate MST_1 may be formed by various methods.

[0137] The distance between middle plate MST_1 and plate PLT (or the distance between middle plate MST_1 and slit pattern PTN) in the folding region FA may be smaller than the distance between middle plate MST_1 and plate PLT in the unfolding regions NFA1 and NFA2. To this end, the vertical middle plate of middle plate MST_1 may further include a third middle plate portion MSTH3 connected to first middle plate portion MSTH1_1 and a fourth middle plate portion MSTH4 connected to second middle plate portion MSTH2_1. The third and fourth middle plate portions MSTH3 and MSTH4 may protrude upward from the surfaces of the first and second middle plate portions MSTH1 and MSTH2, respectively, toward the upper members PNL and PTN. The thicknesses of the third and fourth middle plate portions MSTH3 and MSTH4 may be greater than the thicknesses of the first and second middle plate portions MSTH1 and MSTH2, respectively.

[0138] The surface heights of the third and fourth middle plate portions MSTH3 and MSTH4 may be higher than the surface heights of the first and second middle plate portions MSTH1 and MSTH2, respectively.

[0139] The third and fourth middle plate members MSTH3 and MSTH4 may serve to prevent the cover member CG, the display panel PNL, and the slit pattern PTN in the folding area FA from sagging downward. As described above with reference to FIG. 18, the cover member CG, the display panel PNL, and the slit pattern PTN arranged in the folding area FA may become more warped (or wrinkled) over time if there is no additional support member underneath. However, in the display device 11 according to the second embodiment, the third and fourth middle plate members MSTH3 and MSTH4, which have a higher surface height than the first and second middle plate members MSTH1 and MSTH2, are arranged in the folding area FA, thereby preventing the cover member CG, the display panel PNL, and the slit pattern PTN arranged in the folding area FA from becoming more warped (or wrinkled) over time.

[0140] A protruding height H2 of the third and fourth middle plate portions MSTH3, MSTH4 based on the surface height of the first middle plate portion MSTH1_1 may be smaller than a protruding height H1 of the first coupling member BM1 based on the surface height of the first middle plate portion MSTH1_1. The surface of the first coupling member BM1 may be positioned on the same line as the lower surface of the slit pattern PTN. If the surfaces of the third and fourth middle plate portions MSTH3, MSTH4 are positioned on the same line as the lower surface of the slit pattern PTN and the third and fourth middle plate portions MSTH3, MSTH4 are in direct contact with the slit pattern PTN, physical interference may occur between the slit pattern PTN and the middle plate MST_1 during the folding operation, which may hinder smooth folding.

[0141] In addition, in order for the third and fourth middle plate parts MSTH3 and MSTH4 to prevent bending of the cover member CG, the display panel PNL, and the slit pattern PTN in the folding area FA, it is preferable that the surfaces of the third and fourth middle plate parts MSTH3 and MSTH4 be located between the lower and upper surfaces of the first coupling member BM1. However, without being limited thereto, the surface height of the third and fourth middle plate parts MSTH3 and MSTH4 may be located on the same line as the surface height (or upper surface height) of the first coupling member BM1.

[0142] Furthermore, the third and fourth middle plate parts MSTH3 and MSTH4 are preferably located in the center of the folding area FA to easily prevent the cover member CG, the display panel PNL, and the slit pattern PTN in the folding area FA from bending. Therefore, the first and second middle plate parts MSTH1_1 and MSTH2_1 may extend to the folding area FA. Since the first and second middle plate parts MSTH1_1 and MSTH2_1 extend to the folding area FA and each middle plate part MSTH3 and MSTH4 is connected to the adjacent first and second middle plate parts MSTH1_1 and MSTH2_1, the third and fourth middle plate parts MSTH3 and MSTH4 may be spaced apart from the inner surfaces of the first coupling members BM1 located in the unfolding areas NFA1 and NFA2.

[0143] The third and fourth middle plate portions MSTH3 and MSTH4 of the display device 11 according to the second embodiment may be spaced apart from each other based on a line dividing the folding area FA. The reason for the third and fourth middle plate portions MSTH3 and MSTH4 being spaced apart from each other based on a line dividing the folding area FA is to facilitate the folding operation of the hinge assembly 200 of the display device 10 described above. As described with reference to FIG. 3, the middle plate MST_1 is formed of a material such as plastic, polyimide, or metal to increase the rigidity of the display device 11. Therefore, if the middle plate MST_1 is integrally formed over the unfolding areas NFA1 and NFA2 and the folding area FA, stress on the display device 11 may be increased during the folding operation. Therefore, like the middle plate MST of the display device 10 shown in FIG. 4, the first and third middle plate portions MSTH1_1 and MSTH3 may be physically spaced apart from the second and fourth middle plate portions MSTH2_1 and MSTH4.

[0144] As shown in FIG. 21, when the display device 11 is repeatedly folded and unfolded, the folding area FA may bend downward as shown in FIG.

[0145] To explain in more detail, when the folding area FA is repeatedly folded and unfolded, it undergoes significant deformation, which may cause the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA to sag downward and not return to their original state. Even if the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA are restored, the restoration time may be longer than the predetermined time. In this case, the sagging shape (or wrinkles) may be visible from the outside, which may cause display defects. Furthermore, because there is no other support member below the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA, the sagging shape (or wrinkles) may become more severe over time.

[0146] However, in the display device 11 according to the second embodiment, the third and fourth middle plate members MSTH3 and MSTH4 in the folding area FA are formed to protrude further upward from the surfaces of the first and second middle plate members MSTH1 and MSTH2, respectively, toward the upper members PNL and PTN. This means that even if the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA bend downward due to repeated folding and unfolding, they only bend up to the surfaces of the third and fourth middle plate members MSTH3 and MSTH4 (the third and fourth middle plate members MSTH3 and MSTH4 come into contact with the slit pattern PTN). This reduces the restoration time of the cover member CG, display panel PNL, and slit pattern PTN arranged in the folding area FA.

[0147] Furthermore, it is possible to prevent the bending (or wrinkles) of the folding area FA from being visible from the outside and causing display defects. Also, since the slit pattern PTN bends only up to the surfaces of the third and fourth middle plate portions MSTH3 and MSTH4, it is possible to improve the bending (or wrinkles) phenomenon of the folding area FA.

[0148] In addition, since the middle plate MST_1 is separated from the display panel PNL by the plates PLT and PTN, it is possible to prevent further stress from being applied to the display panel PNL due to the additional formation of the third and fourth middle plate parts MSTH3 and MSTH4.

[0149] The rest of the description has been given above with reference to FIGS. 1 to 18, so detailed description will be omitted.

[0150] The above description and the accompanying drawings merely exemplify the technical concept of the present specification, and various modifications or variations, such as combination, separation, substitution, and alteration of the components, may be made by a person skilled in the art to which the present specification pertains, without departing from the essential characteristics of the present specification. Therefore, the embodiments disclosed in the present specification are intended to illustrate, rather than limit, the technical concept of the present specification, and such embodiments do not limit the scope of the technical concept of the present specification. The scope of protection of the present specification should be interpreted by the following claims, and all technical concepts within the equivalent range should be interpreted as being included in the scope of the present specification. [Explanation of symbols]

[0151] 10:Display device PLT: Plate PTN: Slit pattern MST: Middle plate MSTH1~MSTH4: 1st to 4th middle plates PNL: Display panel CG: Cover material

Claims

1. a panel assembly including: a display panel including a first unfolding area, a second unfolding area, and a folding area between the first unfolding area and the second unfolding area; and a plate disposed below the display panel and including a slit pattern on the folding area; a middle plate disposed below the plate, the middle plate includes a first middle plate portion on the first unfolding region, a second middle plate portion on the second unfolding region, and a vertical middle plate portion on the folding region; The vertical middle plate portion protrudes toward the plate.

2. The display device of claim 1 , wherein the vertical middle plate portion includes a third middle plate portion connected to the first middle plate portion and a fourth middle plate portion connected to the second middle plate portion.

3. The display device of claim 2 , wherein the third middle plate portion and the fourth middle plate portion are spaced apart from each other.

4. The display device according to claim 2 , wherein a distance between the third middle plate portion and the plate is shorter than a distance between the first middle plate portion and the plate.

5. The display device according to claim 2 , wherein a distance between the fourth middle plate portion and the plate is shorter than a distance between the second middle plate portion and the plate.

6. The display device of claim 1 , wherein the first unfolding region and the second unfolding region are folded based on the folding region and overlap each other in a folded state.

7. The display device of claim 6 , wherein in an unfolded state, the slit pattern on the folding region is spaced apart from the vertical middle plate portion.

8. The display device of claim 7 , wherein in the unfolded state, the folding region of the display panel bows downward.

9. The display device of claim 7 , wherein the slit pattern on the folding region directly contacts the vertical middle plate portion.

10. The display device of claim 1 , further comprising an in-folding hinge assembly disposed in the folding region below the panel assembly and including a hinge cover.

11. The display device of claim 10 , further comprising a first frame cover and a second frame cover coupled to the in-folding hinge assembly.

12. the in-folding hinge assembly includes a first hinge arm and a second hinge arm rotatably connected to each other, a first bevel gear and a second bevel gear coupled to the first hinge arm and the second hinge arm in a direction perpendicular to the first hinge arm and the second hinge arm, respectively, and a first gear arm and a second gear arm fastened to interlock with the first hinge arm and the second hinge arm, The display device of claim 10 , wherein the display panel performs folding and unfolding operations around a rotation axis different from the central axes of the first bevel gear and the second bevel gear.

13. the first bevel gear and the second bevel gear are arranged to mesh with each other, The display device of claim 12 , wherein the first bevel gear and the second bevel gear include second idle gears that mesh with first idle gears of the first hinge arm and the second hinge arm, respectively.

14. The display device according to claim 13 , wherein the first idle gear and the second idle gear are disposed perpendicular to each other.

15. a panel assembly including a display panel including a first unfolding area, a second unfolding area, and a folding area between the first unfolding area and the second unfolding area, and a plate disposed below the display panel; a middle plate disposed below the plate, a distance between the middle plate and the plate in the folding region is shorter than a distance between the middle plate and the plate in the first unfolding region; the middle plate includes a first middle plate portion on the first unfolding region, a second middle plate portion on the second unfolding region, and a vertical middle plate portion on the folding region; The vertical middle plate portion protrudes toward the plate.

16. the vertical middle plate portion includes a third middle plate portion connected to the first middle plate portion and a fourth middle plate portion connected to the second middle plate portion; The display device of claim 15 , wherein the third middle plate portion and the fourth middle plate portion are spaced apart from each other.

17. 17. The display device of claim 16, wherein the first unfolding region and the second unfolding region are folded based on the folding region and overlap each other in the folded state, and the slit pattern on the folding region is spaced apart from the vertical middle plate portion in the unfolded state.

18. 18. The display device of claim 17, wherein in the unfolded state, a folding area of ​​the display panel is bent downward, and the slit pattern on the folding area is in direct contact with the vertical middle plate portion.

Images