In-and-out folding hinge device and foldable smartphone having same

Abstract

The present invention relates to an in-and-out folding hinge device and a smartphone having same, the device preventing a chain from being exposed to the outside such that design quality is improved, minimizing problems caused by external impact, contamination and friction, and enabling smooth and stable folding operation while protecting a display panel of the smartphone. The present invention comprises: an in-and-out hinge connecting a first main body and a second main body such that same are rotatable relative to each other; a plurality of first joints arranged continuously in parallel on an upper portion between the first main body and the second main body, arranged symmetrically with respect to a central portion, and bent in a shape in which the interval therebetween decreases when a display panel is in-folded and the interval therebetween increases when the display panel is out-folded; a plurality of second joints continuously arranged in parallel in a lower portion between the first main body and the second main body, arranged symmetrically with respect to the central portion, and bent in a shape in which the interval therebetween increases when the display panel is in-folded and the interval therebetween decrease when the display panel is out-folded; an upper chain connecting the first main body and the second main body on both sides of the first joints so as to guide bending motions of the first joints while being bent during in-folding and out-folding; a lower chain connecting the first main body and the second main body so as to guide bending motions of the second joints while being bent during in-folding and out-folding; and a chain cover covering and concealing the upper chain exposed on both sides of the display panel.

Description

In-and-out folding hinge device and foldable smartphone equipped with the same

[0001] The present invention relates to a hinge device having an In-and-Out folding structure among the folding methods of a smartphone, and in particular, to an In-and-Out folding hinge device that prevents external exposure of the chain to improve design completeness and minimizes problems caused by external impact, contamination, and friction, as well as protecting the display panel of the smartphone and enabling smooth and stable folding operation, and a foldable smartphone equipped with the same.

[0002] Recently, foldable smartphones have been gaining attention in the smartphone market for their ability to expand display size while maintaining portability. Existing foldable smartphones are broadly categorized into in-folding and out-folding types, each with its own advantages and disadvantages.

[0003] The in-folding method has the advantage of protecting the display by folding the screen inward, but it has the disadvantage of increasing thickness and making the hinge structure more complex. The out-folding method allows for continuous use of a single screen by folding the display outward, and while it enables a thinner design, it has the problem of being vulnerable to external impact.

[0004] Against this backdrop, the In-and-Out folding method is emerging as a new alternative. Designed to allow the smartphone to fold both inward and outward, the In-and-Out folding method maximizes user convenience. In other words, it can be used in either an in-folding or out-folding mode depending on the need, enabling flexible utilization while addressing the shortcomings of existing methods.

[0005] However, conventional folding hinge devices have the following problems. There is a risk that the display panel may be damaged when the hinge is folded, and the durability of the hinge may be reduced, particularly during repeated opening and closing. In some existing hinge structures, internal components such as chains or shafts may be exposed to the outside or protrude beyond the panel, which is aesthetically unpleasing and increases the risk of breakage. Furthermore, in some existing hinge designs, the hinge chain (joint structure) is often exposed on the side of the display substrate, which not only degrades the design but also poses a risk of the chain being subjected to external impact. Additionally, the exposed chain may interfere with the display, thereby reducing the durability of the panel.

[0006] When both in-folding and out-folding are supported simultaneously, the display may be subjected to excessive pressure during the folding process, potentially causing creases or damage. Additionally, if the hinge resistance during folding is too strong or, conversely, too loose, usability may be reduced, and there were issues with smooth opening and closing.

[0007] Accordingly, there was an urgent need for a solution that could improve structural stability and durability, minimize the protrusion of internal parts, prevent the exposure of the chain to enhance design completeness, and effectively protect the display panel while enabling smooth folding operation by providing a new hinge mechanism optimized for the in-and-out folding method.

[0008] Accordingly, the present invention is proposed to resolve the aforementioned conventional problems. The objective of the present invention is to provide an in-and-out folding hinge device and a smartphone equipped with the same, which prevents external exposure of the chain to improve design completeness, minimizes problems caused by external impact, contamination, and friction, and enables smooth and stable folding operation while protecting the display panel of the smartphone.

[0009] To achieve the above-mentioned purpose, an in-and-out folding hinge device according to the technical concept of the present invention comprises: an in-and-out folding hinge device in which a flexible display panel is positioned on the inside during an in-folding operation where it folds upward, and a flexible display panel is positioned on the outside during an out-folding operation where it folds downward; an in-and-out hinge that connects a first main body and a second main body so as to be rotatable with respect to each other; a plurality of first joints that are continuously arranged side by side on the upper part between the first main body and the second main body, arranged in a symmetrical form with respect to the center, and are bent in a form in which the gap between them narrows when the display panel folds inward and widens when the display panel folds outward; and a plurality of second joints that are continuously arranged side by side on the lower part between the first main body and the second main body, arranged in a symmetrical form with respect to the center, and are bent in a form in which the gap between them widens when the display panel folds inward and narrows when the display panel folds outward. The technical configuration features include: an upper chain that connects the first body and the second body on both sides of the first joint and guides the bending motion of the first joints while bending during in-folding and out-folding; a lower chain that connects the first body and the second body and guides the bending motion of the second joints while bending during in-folding and out-folding; and a chain cover that covers and conceals the upper chain exposed on both sides of the display panel.

[0010] Here, the first cover sheet may be characterized by being joined to the chain blocks while covering the plurality of chain blocks constituting the upper chain, and by bending in compliance with the in-folding and out-folding operations of the display panel to provide support for maintaining the spacing and relative position of the chain blocks and reinforcing the binding rigidity of the chain blocks.

[0011] Additionally, it further includes a first outer sheet that is bonded to the outer surface of the first cover sheet and bends together to form an exterior, wherein the first cover sheet is made of a material having a relatively lower elongation rate and a higher elastic modulus compared to the first outer sheet, thereby ensuring structural support and shape stability for the chain blocks during in-folding and out-folding operations, and the first outer sheet may be characterized by having a relatively higher elongation rate and a lower elastic modulus compared to the first cover sheet, and being made of a material with higher dispersibility of dyes or pigments to facilitate color realization.

[0012] In addition, the first joint may be characterized by having a rotation guide groove having a cylindrical inner surface and a rotation guide projection protruding to slide in contact along the inner surface of the rotation guide groove of an adjacent first joint, wherein the rotation guide projection protrudes downward at an angle in the width direction, and the lower surface, which is the contact surface with the upper surface, is formed as a gentle convex curved surface such that the thickness in the vertical direction gradually decreases toward the tip, thereby preventing some of the multiple first joints from protruding or sagging during the in-folding and out-folding operations of the display panel.

[0013] In addition, the upper chain may be characterized by including a plurality of chain blocks arranged continuously in a row and having a first connecting axis formed on the side, and a plurality of first links connecting the first connecting axes of adjacent chain blocks.

[0014] In addition, the first link may include a first mounting groove and a second mounting groove that each rotatably support the first connecting axes of adjacent chain blocks, and the second mounting groove may be formed as an elongated groove that is wider from left to right than the first mounting groove, thereby allowing a change in spacing between adjacent chain blocks.

[0015] In addition, the first connecting shaft of the chain block is formed such that the upper surface has a larger curvature than the lower surface, and the lower surface has a relatively smaller curvature than the upper surface, or a flat surface, so as to reduce the upper and lower thickness of the chain block; the first link includes a first semicircular seating groove that allows rotational displacement of the first connecting shaft, and a second seating groove formed as a semicircular elongated groove that is expanded to the left and right to allow rotational displacement and spacing change of the first connecting shaft; the second seating groove may be characterized by having a stopper formed at its upper end, which has a curved joint structure that restricts the first connecting shaft from rotating in the reverse direction beyond a predetermined range.

[0016] Additionally, the second joint may be characterized by having a second connecting axis in the longitudinal direction formed near both ends through injection molding, and the lower chain may include a plurality of chain plates continuously arranged in a row below the second joint, and a plurality of second links that connect adjacent chain plates and, in that state, connect the second connecting axes of the second joint.

[0017] Additionally, the second link may include a third mounting groove and a fourth mounting groove that respectively rotatably support the second connecting axes of adjacent second links, and the fourth mounting groove may be formed as an elongated groove that is wider from left to right than the third mounting groove, thereby allowing for a change in the separation of adjacent second joints.

[0018] Additionally, the second connecting axis of the second joint may be formed such that the lower surface is a curved surface with a large curvature and the upper surface is a curved surface or flat surface with a relatively smaller curvature compared to the lower surface, thereby reducing the upper and lower thickness of the second joint, and the second link may be characterized by including a third seating groove in the shape of a semicircle that allows rotational displacement of the second connecting axis, and a fourth seating groove formed as a semicircular elongated groove that is expanded to the left and right to allow rotational and movable displacement of the second connecting axis.

[0019] In addition, it may further include a second cover sheet that covers and conceals the plurality of first joints and lower chains, and is joined to the chain plates while covering the plurality of chain plates constituting the lower chains, and is bent in compliance with the in-folding and out-folding movements of the display panel to provide support for maintaining the spacing and relative position of the chain plates and reinforcing the binding rigidity of the chain plates.

[0020] Additionally, it further includes a second outer sheet that is bonded to the outer surface of the second cover sheet and bends together to form an exterior, wherein the second cover sheet is made of a material having a relatively lower elongation rate and a higher elastic modulus compared to the second outer sheet, thereby ensuring structural support and shape stability for the chain plates during in-folding and out-folding operations, and the second outer sheet may be characterized by having a relatively higher elongation rate and a lower elastic modulus compared to the second cover sheet, and being made of a material with higher dispersibility of dyes or pigments to facilitate color realization.

[0021] Meanwhile, the foldable smartphone of the present invention includes the aforementioned in-and-out folding hinge device, and is characterized by the fact that the in-folding and out-folding operations of the flexible display panel are stably performed.

[0022] The present invention relates to a folding hinge device that supports both in-folding and out-folding movements, wherein a first joint and a second joint, respectively positioned at the upper and lower portions, act in opposite directions to maintain a uniform folding curvature. Through this, the display panel can be folded and unfolded smoothly and stably, and structural stability and durability can be ensured even during repetitive folding movements.

[0023] The joints include a rotation guide structure and a stopper, which prevents unnecessary reverse rotation or sagging of the joints during folding and guides them to maintain a constant curvature. Therefore, this can contribute to improving the consistency of folding quality and extending the overall durability of the product.

[0024] In addition, the upper and lower chains are linked with the joints to induce precise movement during the folding process and to maintain a constant spacing and a balanced structure. The links and connecting shafts include long grooves and stopper structures with different left and right widths, allowing for effective control of spacing changes or reverse rotation.

[0025] Meanwhile, the chain and joints are protected from the outside through a cover sheet and an exterior sheet, respectively, and this cover structure ensures impact resistance, stain resistance, and wear resistance. In particular, the metal cover sheet provides structural support, while the flexible synthetic resin exterior sheet is advantageous for enhancing design completeness.

[0026] As a result, the folding hinge device of the present invention increases the reliability of the folding operation, prevents performance degradation due to repeated use, and provides a useful structure applicable to various electronic devices such as foldable smartphones.

[0027] FIG. 1 is an operation diagram showing the in-and-out folding operation of a foldable smartphone equipped with an in-and-out folding hinge device according to an embodiment of the present invention.

[0028] FIG. 2 is a perspective view of an in-and-out folding hinge device according to an embodiment of the present invention.

[0029] FIG. 3 is a perspective view of an in-and-out hinge of an in-and-out folding hinge device according to an embodiment of the present invention.

[0030] FIG. 4 is a partial cutaway view illustrating the configuration of the first joint and upper clip of an in-and-out folding hinge device according to an embodiment of the present invention.

[0031] FIG. 5 is an operation diagram showing an in-and-out folding operation according to the configuration of the first joint and upper clip of an in-and-out folding hinge device according to an embodiment of the present invention.

[0032] FIG. 6 is a partial cutaway view illustrating the configuration of the second joint and lower clip of an in-and-out folding hinge device according to an embodiment of the present invention.

[0033] FIG. 7 is an operation diagram showing the in-and-out folding operation according to the configuration of the second joint and lower clip of the in-and-out folding hinge device according to an embodiment of the present invention.

[0034] FIGS. 8 and 9 are reference drawings for explaining the coupling relationship between the second joint and the second link of an in-and-out folding hinge device according to an embodiment of the present invention.

[0035] FIG. 10 is an operation diagram showing the bending of the upper chain, the lower chain, and the flexible display during the in-and-out folding operation of the in-and-out folding hinge device according to an embodiment of the present invention.

[0036] FIG. 11 is a perspective view of a chain module including an upper chain of an in-and-out folding hinge device according to an embodiment of the present invention.

[0037] FIG. 12 is a partial perspective view for explaining a chain cover of an in-and-out folding hinge device according to an embodiment of the present invention.

[0038] FIG. 13 is a reference perspective view for explaining the joint cover of an in-and-out folding hinge device according to an embodiment of the present invention.

[0039] With reference to the attached drawings, an in-and-out folding hinge device according to embodiments of the present invention and a foldable smartphone equipped therewith will be described in detail. Since the present invention is susceptible to various modifications and may take various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to specific disclosed forms, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the present invention. Similar reference numerals have been used for similar components in the description of each drawing. In the attached drawings, the dimensions of the structures are depicted enlarged from the actual size to ensure clarity of the present invention, or reduced from the actual size to allow for understanding of the schematic configuration.

[0040] Additionally, terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component. Meanwhile, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0041] <Example>

[0042] FIG. 1 is an operation diagram showing the in-and-out folding operation of a foldable smartphone equipped with an in-and-out folding hinge device according to an embodiment of the present invention; FIG. 2 is a perspective view of an in-and-out folding hinge device according to an embodiment of the present invention; FIG. 3 is a perspective view of an in-and-out hinge of an in-and-out folding hinge device according to an embodiment of the present invention; FIG. 4 is a partial cutaway view to explain the configuration of the first joint and upper clip of an in-and-out folding hinge device according to an embodiment of the present invention; FIG. 5 is an operation diagram showing the in-and-out folding operation according to the configuration of the first joint and upper clip of an in-and-out folding hinge device according to an embodiment of the present invention; FIG. 6 is a partial cutaway view to explain the configuration of the second joint and lower clip of an in-and-out folding hinge device according to an embodiment of the present invention; and FIG. 7 is an operation diagram showing the in-and-out folding operation according to the configuration of the second joint and lower clip of an in-and-out folding hinge device according to an embodiment of the present invention.

[0043] As described above, the in-and-out folding hinge device (100) according to an embodiment of the present invention includes an in-and-out hinge (110), a first joint (120), a second joint (130), an upper chain (150a), a lower chain (150b), a first cover sheet (170a) and a first outer sheet (170b), a second cover sheet (180a) and a second outer sheet (180b) as main components, thereby preventing external exposure of the upper chain (150a) and the lower chain (150b) to improve design completeness and minimize problems caused by external impact, contamination, and friction, as well as enabling smooth and stable folding operation while protecting the display panel (300) of the foldable smartphone.

[0044] Hereinafter, an in-and-out folding hinge device (100) according to an embodiment of the present invention will be described in detail, focusing on each of the above components.

[0045] The above in-and-out hinge (110) is a core structure that rotatably connects the first body (200a) and the second body (200b) to each other, and is configured to include a support member (111), a pair of rotating blades (112) having a gear part as shown in FIG. 3, a spring (113), a cam member (114), and an end connecting member (111a).

[0046] The support member (111) is located at the center of the in-and-out hinge (110) and allows the first main body (200a) and the second main body (200b) to be stably connected and to perform rotational movement smoothly. A rotating wing (112) is mounted on the support member (111), and the rotating wing (112) is arranged in a pair including a gear part (112a). These rotating wings (112) are interconnected using a gear structure, and are designed so that when one wing rotates, the opposite wing also moves in the same direction. Through this, the hinge can support both in-folding and out-folding movements.

[0047] A rotation axis of the hinge is formed at one end of the rotating wing (112), thereby allowing the first main body (200a) and the second main body (200b) to rotate smoothly around the hinge. Additionally, end connecting members are arranged at both ends of the rotating wing (112), thereby providing a structurally stable connection. The end connecting members connect the hinge to the main body and assist in preventing the hinge axis from shaking during the folding operation.

[0048] The spring (113) is positioned between the rotating blades (112) and provides a uniform elastic force when the hinge performs in-folding and out-folding movements, thereby enabling smooth rotation. The spring (113) prevents the hinge from moving abruptly or uneven force from being applied during folding, and serves to prevent damage to the display panel (300).

[0049] The cam member (114) functions to adjust the rotation angle during the folding operation in conjunction with the rotating wing (112) and the support member (111). The cam member (114) functions to induce the rotational movement of the hinge in a certain pattern, thereby assisting in the folding operation to be performed with a certain force and angle. Through this, the force applied to the display panel (300) during folding is optimized, and the user can feel a certain resistance when folding.

[0050] This in-and-out hinge (110) causes the first main body (200a) and the second main body (200b) to rotate along a certain trajectory when performing a folding operation, and serves to provide smooth and stable operation during the folding process of the display panel (300). In addition, the combination of the spring (113) and the cam member (114) ensures that the rotation of the hinge proceeds at a uniform speed, thereby preventing damage to the display panel (300) and providing the effect of maintaining structural stability even during long-term use.

[0051] The first joint (120) is arranged continuously in parallel on the upper portion between the first main body (200a) and the second main body (200b), and is arranged in a symmetrical form with respect to the center. A plurality of first joints (120) have a structure in which the spacing between them narrows during the in-folding operation of the display panel (300) and the spacing widens during the out-folding operation. Through this, the display panel (300) can be folded and unfolded smoothly and can operate stably even during repetitive folding operations.

[0052] The first joint (120) includes a rotation guide groove (123) having a cylindrical inner surface and a rotation guide projection (124) protruding to slide in contact with the inner surface of the rotation guide groove (123) of an adjacent first joint (120). The rotation guide projection (124) protrudes downward at an angle in the width direction and forms a gentle convex curved surface in which the thickness in the vertical direction gradually decreases toward the tip, thereby preventing some of the multiple first joints (120) from protruding irregularly or sagging during in-folding and out-folding operations.

[0053] Additionally, a stopper (125) for controlling the rotation angle is provided between each first joint (120). The stopper (125) is made of a curved joint structure and suppresses unnecessary reverse rotation or excessive movement of the joint during in-folding and out-folding operations. This stopper structure maintains a constant folding curvature by appropriately limiting the range of rotation of the joint, and ensures that the folding curve of the display panel (300) is formed stably.

[0054] This structure of the first joint (120) contributes to evenly distributing the load generated during the folding of the display panel (300), reducing structural stress, and improving the consistency of the folding quality. This improves the durability of the display panel (300) and enables balanced folding operation even in a long-term, repetitive use environment.

[0055] The second joint (130) is arranged continuously in parallel at the lower portion between the first main body (200a) and the second main body (200b), and is arranged in a symmetrical form with respect to the center. The plurality of second joints (130) have a structure in which the spacing between them widens during the in-folding operation of the display panel (300) and narrows during the out-folding operation, and this acts in the opposite direction to the first joint (120) placed at the top. Through this structure, the upper and lower joints move complementarily, allowing the overall folding curvature to be maintained uniformly.

[0056] A second connecting shaft (131) in the longitudinal direction is formed near both ends of the second joint (130) through injection molding. The second connecting shaft (131) is connected to a plurality of chain plates included in the lower chain (150b) to enable precise movement and spacing of the second joint (130) during folding operation. At this time, the lower surface of the second connecting shaft (131) is formed as a curved surface with a large curvature, and the upper surface is formed as a curved surface or flat surface with a relatively small curvature, thereby minimizing the vertical thickness of the second joint (130) and reducing interference with the display panel (300).

[0057] The lower chain (150b) is composed of a chain plate that is continuously arranged in a row in conjunction with a plurality of second joints (130), and a plurality of second links (132) that connect the second connecting shafts (131) of adjacent chain plates and second joints (130). The second links (132) include a third mounting groove (133) and a fourth mounting groove (134) that each rotatably support the second connecting shafts (131). At this time, the fourth mounting groove (134) is formed as an elongated groove that is wider from left to right than the third mounting groove (133), so that a change in the distance between the second joints (130) is naturally allowed. In addition, a curved structure that acts as a stopper (135) is formed inside the elongated groove, thereby preventing the second connecting shafts (131) from rotating excessively in the reverse direction and maintaining stable movement.

[0058] This structure maintains a uniform folding angle of the second joint (130) and prevents some joints from unintentionally protruding or sagging during the folding process, thereby improving the structural stability of the display panel (300). Additionally, the lower chain (150b) is integrated as a structure that guides the movement of the second joint (130), and the chain and joint operate in conjunction, providing the effect of functioning as a single continuous structure.

[0059] As a result, the second joint (130) effectively distributes the load during in-folding and out-folding movements and performs the function of preventing damage to the display panel (300) and improving durability by maintaining a constant curvature and spacing.

[0060] The upper chain (150a) connects the first body (200a) and the second body (200b) on both sides of the first joint (120) and serves to guide the bending motion of the first joint (120) as it bends during in-folding and out-folding. The upper chain (150a) adjusts the movement of the first joints (120) and maintains a constant distance during the folding process to ensure uniformity of the overall folding curvature.

[0061] As shown in FIGS. 4 and 5, the upper chain (150a) comprises a plurality of chain blocks (151) arranged in a continuous line and a plurality of first links (153) connecting the first connecting shafts (151a) of adjacent chain blocks (151). The chain blocks (151) are the basic units of the upper chain, and a first connecting shaft (151a) is formed on the side of each chain block and rotatably connected to the first links (153).

[0062] The first connecting shaft (151a) has a semicircular cross-section formed such that the upper surface is a curved surface with a greater curvature than the lower surface, and the lower surface is a curved surface or flat surface with a relatively smaller curvature. This structure is advantageous for reducing the vertical thickness of the chain block (151) and minimizing interference with the display panel (300) during folding operation.

[0063] The first link (153) is a structure that allows for rotation and spacing changes of the first connecting shaft (151a) and includes a first seating groove (153a) and a second seating groove (153b). The second seating groove (153b) is formed as an elongated groove that is wider from left to right than the first seating groove (153a), so that it can flexibly respond to changes in spacing between adjacent chain blocks. In addition, a stopper with a curved joint structure is formed on the upper end of the second seating groove (153b), thereby ensuring stable operation of the joint by limiting the rotation of the first connecting shaft (151a) so that it does not exceed a certain range.

[0064] The upper chain (150a) evenly distributes the load during the folding operation and prevents the first joint (120) from folding at different angles, thereby maintaining consistent folding quality. This contributes to the display panel (300) folding and unfolding smoothly and maintaining structural reliability even during repeated operations.

[0065] Additionally, the upper chain (150a) is combined with the first cover sheet (170a) and the first exterior sheet (170b) to conceal it from the outside. The first cover sheet (170a) is made of stainless steel and is bonded to the chain block (151) to provide structural support, while the first exterior sheet (170b) is made of elastomer or synthetic resin and is flexible and takes charge of the exterior design. This protects the chain structure from external impact, contamination, and friction, and improves the durability of the chain so that stable folding performance can be maintained even during long-term use.

[0066] Consequently, the upper chain (150a) guides the folding curvature of the first joint (120) to be uniform and is a key element that enables the folding and unfolding of the display panel (300) to be smooth and stable.

[0067] As shown in FIGS. 4 and 6, the lower chain (150b) connects the first body (200a) and the second body (200b) on both sides of the second joint (130) and serves to guide the bending motion of the second joint (130) as it bends during in-folding and out-folding. The lower chain (150b) is designed to regulate the movement of the second joints (130) consistently and to ensure structural stability when the folding motion is repeated.

[0068] The lower chain (150b) includes a plurality of chain plates (155) arranged in a continuous line on the lower side of the second joint (130), and a plurality of second links (156) connecting the adjacent chain plates (155) and the second connecting shafts (131) of the second joint (130). The chain plates (155) form the basic structure of the lower chain (150b), and the second connecting shafts (131) are formed on both sides and coupled with the second links (156).

[0069] The second connecting shaft (131) has a semicircular cross-section formed such that the lower surface is a curved surface with a large curvature, and the upper surface is a curved surface or flat surface with a relatively small curvature. This shape reduces the upper and lower thickness of the chain plate (155), thereby reducing interference with the display panel (300) when folded and enabling the entire device to be slimmed down.

[0070] The second link (156) includes a third mounting groove (156a) and a fourth mounting groove (156b) so as to flexibly respond to changes in rotation and spacing of the second connecting shaft (131). The fourth mounting groove (156b) is configured in the shape of an elongated groove that is wider from left to right than the third mounting groove (156a) to respond to changes in spacing between adjacent second joints (130). Additionally, a stopper structure is formed at the top of the fourth mounting groove (156b) to prevent the second connecting shaft (131) from rotating excessively in the reverse direction and to maintain a stable folding operation.

[0071] As illustrated in FIGS. 5 and 7, the lower chain (150b) operates in conjunction with the movement of the second joint (130) to evenly distribute the load throughout the chain during folding and to ensure that the spacing between the second joints (130) remains constant. In particular, the second joint (130) and the lower chain (150b) operate in conjunction as if they were substantially integrated structures, allowing the display panel (300) to be folded and unfolded smoothly.

[0072] As a result, the lower chain (150b) precisely guides the movement of the second joint (130) and provides various functional effects such as maintaining consistency of the folding curvature, minimizing structural interference, and improving durability. This enables the display panel (300) to operate stably without performance degradation even during repeated folding movements.

[0073] The first cover sheet (170a) is structured to cover and conceal the upper chain (150a) exposed on both sides of the display panel (300), and is arranged in a manner that wraps around a plurality of chain blocks (151) constituting the upper chain. The first cover sheet (170a) is made of stainless steel and is bonded to the chain blocks (151) to provide support so that it can stably maintain the spacing and relative position between the chain blocks by bending together during in-folding and out-folding operations. In addition, it reinforces the binding rigidity of the chain blocks to ensure precise movement of the chain during the folding process.

[0074] The first cover sheet (170a) is configured to be attached to the chain support member or to the fixed portions of the first body (200a) and the second body (200b), and a robust connection can be achieved using various methods such as adhesive, mechanical fastening, screw fixing, or welding. This protects the chain structure from being exposed to the outside and prevents damage caused by external impact or friction.

[0075] The first outer sheet (170b) is bonded to the outer surface of the first cover sheet (170a) and bends together to form the exterior. The first outer sheet (170b) is formed of an elastomer or synthetic resin and has a higher elongation rate and a lower elastic modulus than the first cover sheet (170a). Accordingly, it can flexibly deform during the folding motion while ensuring freedom in the exterior design. In addition, it is composed of a material with excellent dispersibility for dyes or pigments, enabling the realization of various colors and contributing to the completeness of the product design and consumer satisfaction.

[0076] The first cover sheet (170a) and the first outer sheet (170b) stably protect the chain from the external environment without interfering with the movement of the upper chain during the folding operation, and allow durability and reliability to be maintained even during repeated folding operations.

[0077] The second cover sheet (180a) is a structure that covers and conceals a plurality of second joints (130) and lower chains (150b) during the in-folding and out-folding operations of the display panel (300), and is formed by being joined to a plurality of chain plates (155) on the lower side of the second joints. The second cover sheet (180a) is made of stainless steel and is bent together with the chain plates (155) while joined, and provides support to maintain the spacing and relative position between the chains during the folding operation. In addition, structural stability is secured by reinforcing the binding rigidity of the chain and joint structures.

[0078] The second cover sheet (180a) is joined to the lower structure of the first body (200a) and the second body (200b) in a left-right divided form and is designed to be firmly fixed by means of adhesive, screw fastening, mechanical connection, or welding. This prevents external exposure of the second joint and lower chain and serves to protect them from external impact or friction.

[0079] The second outer sheet (180b) is a component that is combined with the outer side of the second cover sheet (180a) and is bent together to provide an exterior finish. The second outer sheet (180b) is composed of an elastomer or synthetic resin and is made of a polymer material that has a higher elongation rate and a lower elastic modulus than the second cover sheet (180a) and allows for the realization of various colors. Accordingly, flexible folding movements are possible, while ensuring color harmony and aesthetic unity with the product's exterior.

[0080] The second cover sheet (180a) and the second outer sheet (180b) prevent friction between the second joint (130) and the display panel (300) during folding operation and induce the joint to operate smoothly, thereby providing the effect of improving folding precision. In addition, the joint structure is not exposed to the outside even after repeated folding operations, thereby improving product reliability and durability.

[0081] As described above, the in-and-out folding hinge device (100) of the present invention is designed to support both in-folding and out-folding operations, and the first joint (120), second joint (130), upper chain (150a), lower chain (150b), first cover sheet (170a), first outer sheet (170b), second cover sheet (180a), and second outer sheet (180b) are organically combined to achieve stable and precise folding operation of the display panel (300).

[0082] The first joint (120) and the second joint (130) are positioned at the upper and lower portions of the first main body (200a) and the second main body (200b), respectively, and move complementarily during the folding operation to maintain a constant folding curvature and prevent interference between the joints.

[0083] The upper chain (150a) includes a chain block (151) and a first link (153), and the lower chain (150b) consists of a chain plate (155) and a second link (156). These chains each guide the bending motion of the first joint (120) and the second joint (130), and induce the maintenance of a constant distance during folding.

[0084] The first cover sheet (170a) and the second cover sheet (180a) are made of stainless steel and are bonded to the chain block (151) or chain plate (155), providing structural support and binding rigidity during folding operations. The first outer sheet (170b) and the second outer sheet (180b) are formed of elastomer or synthetic resin, allowing them to be flexibly bent while finishing the exterior, and enabling the realization of various colors, thereby enhancing the aesthetics and completeness of the product.

[0085] The hinge device (100) configured in this way stably protects the display panel (300), maintains durability even during repeated folding processes, and can be applied to various electronic devices including foldable smartphones.

[0086] Although preferred embodiments of the present invention have been described above, the present invention may use various variations, modifications, and equivalents. It is clear that the present invention can be applied in the same way by appropriately modifying the above embodiments. Therefore, the above description does not limit the scope of the present invention, which is defined by the limitations of the following claims.

Claims

1. An in-and-out folding hinge device in which a flexible display panel is positioned on the inside during an in-folding operation where it folds upward, and a flexible display panel is positioned on the outside during an out-folding operation where it folds downward, An in-and-out hinge connecting the first main body and the second main body so as to be rotatable with each other; A plurality of first joints that are arranged continuously side by side on the upper portion between the first main body and the second main body, arranged in a symmetrical form with respect to the center, and are bent such that the gap between them narrows when the display panel is in-folded and the gap between them widens when the display panel is out-folded; A plurality of second joints that are arranged continuously side by side in the lower portion between the first main body and the second main body, arranged symmetrically with respect to the center, and are bent such that the distance between them widens when the display panel is in-folded and the distance between them narrows when the display panel is out-folded; An upper chain that connects the first main body and the second main body on both sides of the first joint and guides the bending movement of the first joints while bending during in-folding and out-folding; A lower chain connecting the first main body and the second main body to guide the bending movement of the second joints while bending during in-folding and out-folding; and An in-and-out folding hinge device characterized by including a first cover sheet that covers and conceals the upper chain exposed on both sides of the display panel.

2. In Paragraph 1, An in-and-out folding hinge device characterized in that the first cover sheet is joined to the chain blocks while covering a plurality of chain blocks constituting the upper chain, and is bent in compliance with the in-folding and out-folding operations of the display panel, thereby providing a supporting force to maintain the spacing and relative position of the chain blocks and reinforcing the binding rigidity of the chain blocks.

3. In Paragraph 2, It further includes a first exterior sheet that is bonded to the outer surface of the first cover sheet and is bent together to form the exterior, and The first cover sheet is made of a material having a relatively lower elongation rate and a higher elastic modulus compared to the first outer sheet, thereby ensuring structural support and shape stability for the chain blocks during in-folding and out-folding operations. An in-and-out folding hinge device characterized in that the first outer sheet has a relatively high elongation rate and a low elastic modulus compared to the first cover sheet, and is made of a material with higher dispersibility of dyes or pigments to facilitate color realization.

4. In Paragraph 1, The first joint is provided with a rotation guide groove having a cylindrical inner surface and a rotation guide projection protruding to slide in contact with the inner surface of the rotation guide groove of an adjacent first joint. An in-and-out folding hinge device characterized in that the above-mentioned rotary guide projection protrudes downward at an angle in the width direction, and the lower surface, which is the contact surface with the upper surface, is formed as a gentle convex curved surface such that the thickness in the vertical direction gradually decreases toward the tip, thereby preventing some of the plurality of first joints from protruding or sagging during the in-folding and out-folding operations of the display panel.

5. In Paragraph 1, An in-and-out folding hinge device characterized by the upper chain comprising a plurality of chain blocks arranged continuously in a row and having a first connecting axis formed on the side, and a plurality of first links connecting the first connecting axes of adjacent chain blocks.

6. In Paragraph 5, The first link above includes a first seating groove and a second seating groove that each rotatably supports the first connecting axes of adjacent chain blocks, and An in-and-out folding hinge device characterized in that the second seating groove is formed as an elongated groove with a wider width from left to right than the first seating groove, allowing for a change in spacing between adjacent chain blocks.

7. In Paragraph 6, The first connecting shaft of the chain block is formed such that the upper surface is a curved surface with a greater curvature than the lower surface, and the lower surface is a curved surface or flat surface with a relatively smaller curvature than the upper surface, thereby allowing the upper and lower thickness of the chain block to be reduced. The first link comprises a first semicircular seating groove that allows rotational displacement of the first connecting shaft, and a second seating groove formed as a semicircular elongated groove that is expanded laterally to allow rotational displacement and spacing changes of the first connecting shaft. An in-and-out folding hinge device characterized in that the second seating groove has a stopper formed at its upper end having a curved coupling structure that restricts the first connecting shaft from rotating in the reverse direction beyond a predetermined range.

8. In Paragraph 1, The second joint has a second longitudinal connecting axis formed near both ends through injection molding, and An in-and-out folding hinge device characterized in that the lower chain comprises a plurality of chain plates arranged in a continuous line below the second joint and a plurality of second links connecting adjacent chain plates and connecting the second connecting axes of the second joint in that state.

9. In Paragraph 8, The second link above includes a third seating groove and a fourth seating groove that respectively rotatably support the second connecting axes of adjacent second links, and An in-and-out folding hinge device characterized in that the fourth seating groove is formed as an elongated groove with a wider width from left to right than the third seating groove, thereby allowing a change in the separation of adjacent second joints.

10. In Paragraph 9, The second connecting axis of the second joint is formed such that the lower surface is a curved surface with a large curvature, and the upper surface is a curved surface or flat surface with a relatively smaller curvature compared to the lower surface, thereby allowing the upper and lower thickness of the second joint to be reduced. An in-and-out folding hinge device characterized in that the second link comprises a third seating groove in the shape of a semicircle that allows rotational displacement of the second connecting shaft, and a fourth seating groove formed as a semicircular elongated groove that is expanded to the left and right to allow rotational displacement and movement displacement of the second connecting shaft.

11. In Paragraph 1, An in-and-out folding hinge device characterized by further including a second cover sheet that covers and conceals the plurality of first joints and lower chains, covers the plurality of chain plates constituting the lower chains, and is joined to the chain plates, and bends in compliance with the in-folding and out-folding operations of the display panel to provide support for maintaining the spacing and relative position of the chain plates and reinforcing the binding rigidity of the chain plates.

12. In Paragraph 11, It further includes a second exterior sheet that is bonded to the outer surface of the second cover sheet and bends together to form the exterior, and The second cover sheet is made of a material having a relatively lower elongation rate and a higher elastic modulus compared to the second outer sheet, thereby ensuring structural support and shape stability for the chain plates during in-folding and out-folding operations. An in-and-out folding hinge device characterized in that the second outer sheet has a relatively high elongation rate and a low elastic modulus compared to the second cover sheet, and is made of a material with higher dispersibility of dyes or pigments to facilitate color realization.

13. Includes an in-and-out folding hinge device according to any one of claims 1 to 12, A foldable smartphone characterized by stable in-folding and out-folding operations of a flexible display panel.

Images