Patent ID: 12204375

DETAILED DESCRIPTION

Exemplary embodiments are described in greater detail below with reference to the accompanying drawings.

In the following description, like drawing reference numerals are used for like elements, even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of the exemplary embodiments. However, it is apparent that the exemplary embodiments can be practiced without those specifically defined matters. Also, well-known functions or constructions are not described in detail because they would obscure the description with unnecessary detail.

As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

The exemplary embodiments now will be described more fully hereinafter with reference to the accompanying drawings. In the drawings, like reference numerals denote like elements, and sizes or thicknesses of elements may be exaggerated for clarity.

FIG.1is a perspective view illustrating an outer appearance of an electronic device100that is foldable, according to an exemplary embodiment.FIG.2is a side view illustrating an unfolded state of the electronic device100ofFIG.2.FIG.3is a side view illustrating a folded state of the electronic device100according to an exemplary embodiment.

Referring toFIGS.1,2, and3, the electronic device100includes first and second bodies1and2, a flexible display element4, and a hinge unit3. The flexible display element4is supported by the first body1and the second body2. For example, the flexible display element4may be adhered to the first body1and the second body2by using an adhesive member such as an adhesive or a double-sided tape. The hinge unit3is disposed between the first and second bodies1and2, and foldably connects the first and second bodies1and2.

The electronic device100may be a portable mobile device such as a communication terminal, a game console, a multimedia player, a portable computer, or an imaging device. The electronic device100may be any of other devices including the first body1that performs a main function and allows a first portion4aof the flexible display element4to be coupled thereto and the second body2that allows a second portion4bof the flexible display element4to be coupled thereto and is foldably connected to the first body1by using the hinge unit3.

A processing unit and an input/output unit for performing a function according to the use of the electronic device100may be provided in or on the first and second bodies1and2. For example, according to an exemplary embodiment, when the electronic device100is a multimedia player that may provide an image and an audio file, the processing unit may include an image/sound information processing unit. Alternatively, when the electronic device100is a communication terminal, the processing unit may include a communication module. The input/output unit may include an image/sound input/output unit and a manipulation unit for user manipulation. The manipulation unit may include a touch panel that is integrated into the flexible display element4and/or, a button, a microphone, and/or a camera that is integrated into either one of the first or second bodies.

The flexible display element4may be divided into the first portion4athat is coupled to the first body1, the second portion4bthat is coupled to the second body2, and a third portion4cthat is disposed between the first body1and the second body2. The third portion4cof the flexible display element4may not be fixed to the hinge unit3. As the third portion4cof the flexible display element4is bent, the electronic device100may be folded as shown inFIG.3. In a folded state in which the electronic device100is folded, the hinge unit3is disposed outside the flexible display element4, to form a curved portion3ahaving a predetermined curvature as shown inFIG.3. In this folded state, because the hinge unit3cannot be bent any further, the third portion4cof the flexible display element4may be protected from being bent sharply beyond the predetermined curvature.

FIG.4is a cross-sectional view of a hinge unit3, illustrating an unfolded state of an electronic device, according to an exemplary embodiment. Referring toFIG.4, the hinge unit3includes a support member310that is soft, and a plurality of slit members320each including a fixed end321that is supported by the support member310and a free end322that extends from the fixed end321. The support member310may be formed of an elastomer such as a rubber that may be freely bent and has flexibility. Each of the plurality of slit members320may have a rod shape that extends in a width direction W (seeFIG.1) of the flexible display element4. According to another exemplary embodiment, the plurality of slit members320may each have a pillar shape with similar dimensions in the W direction as in the L direction. Alternatively, the plurality of slit members320may include slit members with different shapes in the W direction, for example, some may be rod shaped while others may be pillar shapes while others may have other shapes in the W direction.

A cross-sectional view along the L direction as shown in, for example,FIG.4or5, of each of the slit members320may be, for example, a quadrangular shape. The plurality of slit members320are arranged in a longitudinal direction L (seeFIG.1) of the flexible display element4to be spaced apart from each other. When a pitch between the plurality of slit members320is P and a thickness of each of the slit members320is T, an initial interval Gi between two adjacent slit members320is P-T.

According to another exemplary embodiment, the plurality of slit members320may each have a trapezoidal shape, and more specifically an isosceles trapezoid shape, when viewed from a cross-sectional view along the L direction. Particularly, at the free end of the plurality of slit members the distance between each slit member may still be spaced apart by the interval Gi. However, at the fixed end of the plurality of slit members the distance may be reduced such that that the slits meet at a point. Further, the open space defined by the interval Gi portion when in an unfolded state will completely disappear by being filled with the the plurality of slit members due to their trapezoidal shape which would indicate and coincide with an electronic device being in a completely folded state. Further, the shape of the plurality of slit members in cross section may be a number of other shapes such as a conical frustum, a hemisphere, an elliptical cone, a parabolic cone, or any combination thereof.

The slit member320is formed of a material that is harder than that of the support member310. For example, the slit member320may be formed of plastic, metal, or ceramic. For example, the hinge unit3including the plurality of slit members320whose fixed ends321are supported by the support member310may be manufactured by arranging the plurality of slit members320in a mold at predetermined pitches P to make the slit members320spaced apart from each other and injecting an elastomer that is a material of the support member310into the mold. Both end portions of the support member310in the longitudinal direction L may be fixed to the first and second bodies1and2. Also, both end portions of the support member310may be supported by holders and the holders may be fixed to the first and second bodies1and2. According to another exemplary embodiment, the support member and plurality of slit members may be formed from the same flexible material.

In the unfolded state ofFIG.4, the support member310has a linear shape, and an interval between the free ends322of the plurality of slit members320and an interval between the fixed ends321of the plurality of slit members320are the same as the initial interval Gi.

FIG.5is a cross-sectional view of the hinge unit3, illustrating a partially folded state where the electronic device100is folded at a predetermined angle, according to an exemplary embodiment. Referring toFIG.5, the support member310has an arc shape having a curvature. A radius of curvature of an inner circumferential surface312of the support member310is less than a radius of curvature of an outer circumferential surface311of the support member310. Because the support member310is a soft member, the plurality of slit members320are centered around a center C of the support member310having the arc shape, the free ends322of the plurality of slit members320are moved closer to each other, and thus an interval G2is less than the initial interval Gi.

FIG.6is a cross-sectional view of the hinge unit3, illustrating a completely folded state where the electronic device100is completely folded, according to an exemplary embodiment.

Referring toFIG.6, the free ends322of the plurality of slit members320contact each other, and thus the hinge unit3forms the curved portion3ahaving a predetermined radius of curvature r. The radius of curvature r of the curved portion3athat is formed by the hinge unit3is determined by the thickness T (seeFIG.4) of each of the plurality of slit members320, the pitch P (seeFIG.4) between the slit members320, and the number of the slit members320. In this completely folded state, even when the hinge unit3tries to be further bent, because the free ends322of the plurality of slit members320that are each formed of a hard material contact each other, the hinge unit3will not bent any further. In this completely folded state, because the flexible display element4is disposed inside the hinge unit3, the flexible display element4may be protected by the hinge unit3from being sharply bent.

FIG.7is a cross-sectional view of the hinge unit3when the electronic device100is folded in a direction opposite to a folding direction. Referring toFIG.7, because the support member310is a soft member, the hinge unit3may be bent in the direction opposite to the folding direction. When the electronic device100is folded such that the flexible display element4is disposed outside the hinge unit3, because the flexible display element4is coupled to the first and second bodies1and2and thus a length of the flexible display element4is not increased, a tensile force may be applied to the flexible display element4and thus the flexible display element4may be separated from the first and second bodies1and2or the flexible display element4may be damaged. Referring toFIGS.5and6, when the hinge unit3is bent in the folding direction, the free ends322of the plurality of slit members321are moved closer to each other. That is, an interval between the free ends322of the plurality of slit members320is less than the initial interval Gi. In contrast, when the hinge unit3is bent in the direction opposite to the folding direction as shown inFIG.7, the free ends322of the plurality of slit members320are moved farther away from each other. That is, an interval Go between the free ends322of the plurality of slit members320is greater than the initial interval Gi. Hence, the hinge unit3may be prevented from being bent in the direction opposite to the folding direction by restricting the free ends322of the plurality of slit members320from being moved farther away from each other. For example, the hinge unit3may be prevented from being bent in the direction opposite to the folding direction by limiting an interval between the free ends322of the plurality of slit members320not to be greater than an interval in the unfolded state, that is, the initial interval Gi.

According to one exemplary embodiment, a second plurality of slit members, which may serve as gap-widening prevention members, may be provided in order to avoid bending in the opposite direction which would create an interval of Go between the free ends of the first plurality of slit members which could possibly damage or disconnected the flexible display element. Particularly, the second plurality of slit members may be provided such that their fixed ends are attached on a lower surface opposite the upper surface upon which the first plurality of slit members is attached. Further, the second plurality of slit members free ends extend downward in the opposite direction as the first plurality of slit members. The interval between each slit member of the second plurality of slit members may be set such that the opposite bending is either avoided entirely, by making the interval near zero, or restricted to an acceptable bending shape by adjusting the interval and shape of the second plurality of slit members similar to the adjustment made to the first plurality of slit members.

According to another exemplary embodiment,FIG.8is a plan view illustrating the hinge unit3that may limit a bending direction, according to an exemplary embodiment. Referring toFIG.8, the hinge unit3further includes gap-widening prevention members330that prevent the free ends322of the plurality of slit members320from moving farther away from each other that the interval provided in an unfolded state. The plurality of gap-widening prevention members330may be arranged in a zigzag fashion to connect adjacent slit members320. According to another exemplary embodiment, the gap-widening prevention members330may be, for example, clip members that each surround outer surfaces of two adjacent slit members320-1and320-2. Holders340are disposed on both end portions of the support member310in the longitudinal direction L, support the support member310, and are coupled to the first and second bodies1and2.

FIG.9is an exploded perspective view illustrating an example where each of the gap-widening prevention members330and the slit members320-1and320-2are coupled to each other. Referring toFIGS.8and9, the gap-widening prevention member330includes wing portions331and332that prevent the free ends322of the slit members320-1and320-2from being moved farther away from each other, and a connection portion333that connects the wing portions331and332. Recesses320-1band320-2bthat are recessed inward from outer surfaces320-1aand320-2aare respectively formed in the slit members320-1and320-2, and the wing portions331and332are respectively inserted into the recesses320-1band320-2b. The recesses320-1band320-2bare recessed downward from the free ends322of the slit members320-1and320-2. An outer interval Gw of the wing portions331and332may be equal to or less than a sum of the initial interval Gi and thicknesses of the slit members320-1and320-2. In this configuration, the initial interval Gi is not affected by thicknesses of the wing portions331and332. However, the present exemplary embodiment is not limited thereto, and the wing portions331and332may be supported by outer surfaces320-1aand320-2aof the slit members320-1and320-2as marked by dashed lines ofFIG.8, and the wing portions331and332may be disposed in the initial interval Gi between the slit members320. In this case, the initial interval Gi, the pitch P between the slit members320, and the number of the slit members320may be appropriately determined in consideration of the radius of curvature r in the folded state.

A coupling unit to which the gap-widening prevention member330is coupled is provided in the slit members320-1and320-2. The coupling unit may include slots320-1eand320-2ethat are formed in barrier walls320-1dand320-2dbetween the recesses320-1band320-2band inner surfaces320-1cand320-2cof the slit members320-1and320-2. The connection portion333may be inserted into the slots320-1eand320-2e. A separation prevention unit may be provided in the slots320-1eand320-2eto prevent the connection portion333that is inserted into the slots320-1eand320-2efrom being separated from the slots320-1eand320-2e.FIG.10is a side view illustrating the separation prevention unit according to an exemplary embodiment.

Further, referring toFIGS.9and10, the separation prevention unit may include, for example, protrusions320-1fand320-2fthat protrude inward from both side walls of the slots320-1eand320-2e. A width W1of each of the slots320-1eand320-2eis greater than a width W3of the connection portion333, and an interval W2between each of the protrusions320-1fand320-2fis less than the width W3of the connection portion333. The interval W2between each of the protrusions320-1fand320-2fis set so as to allow the connection portion333to pass therethrough when a predetermined force is applied downward to the connection portion333that is placed over the slots320-1eand320-2e. For example, when the slit members320-1and320-2are formed of a material that is softer than that of the gap-widening prevention member330, the interval W2between each of the protrusions320-1fand320-2fmay be slightly increased due to a force for pressing downward the connection portion333and thus the connection portion333may pass through the protrusions320-1fand320-2f.

FIG.11is a cross-sectional view illustrating a state where the hinge unit3is bent in the folding direction, and the free ends322of the slit members320-1and320-2are moved closer to each other. Referring toFIG.11, the free ends322of the slit members320-1and320-2may be freely inclined in order to be moved closer to each other. To this end, a gap may be formed between the connection portion333and the slots320-1eand320-2e. Because the width W1of each of the slots320-1eand320-2eis greater than the width W3of the connection portion333, the connection portion333may be moved in a width direction of each of the slots320-1eand320-2ein each of the slots320-1eand320-2e. Also, a depth from each of the protrusions320-1fand320-2fto each of bottoms320-1gand320-2gof the slots320-1eand320-2eis determined such that after passing through the protrusions320-1fand320-2f, the connection portion333may be moved vertically (in an insertion direction) between the protrusions320-1fand320-2fand the bottoms320-1gand320-2g. Accordingly, when the hinge unit3is bent in the folding direction, the free ends322of the slit members320-1and320-2may be naturally inclined to be moved closer to each other.

Although two protrusions320-1fand320-2fare formed in each of the slots320-1eand320-2einFIGS.9and10, the present exemplary embodiment is not limited thereto. For example, one protrusion320-1for320-2fthat protrudes inward from one side wall of the slot320-1eor320-2emay be formed. In this case, the interval W2is an interval between the protrusion320-1for320-2fand an internal surface of the slot320-1eor320-2ethat faces the protrusion320-1for320-2f.

FIG.12is a cross-sectional view illustrating an unfolded state of the hinge unit3that may limit the bending direction ofFIGS.8through11, according to an exemplary embodiment.FIG.13is a cross-sectional view illustrating a folded state of the hinge unit3that may limit the bending direction ofFIGS.8through11, according to an exemplary embodiment. Referring toFIG.12, in the unfolded state of the hinge unit3, the initial interval Gi between the slit members320is maintained. In this state, even when a force F1is applied to the hinge unit3to move the free ends322of the slit members320farther away from each other, because the free ends322of the slit members320are restricted from being moved away from each other due to the gap-widening prevention members330, the hinge unit3is not bent. Accordingly, a tensile force may be prevented from being applied to the flexible display element4, and thus the flexible display element4may be prevented from being damaged or the flexible display element4and the first and second bodies1and2may be prevented from being de-coupled from each other.

When the free ends322of the slit members320are moved closer to each other, the free ends322of the slit members320are not restricted by the gap-widening prevention members330. Hence, when a force F2that is the opposite to a force F1is applied to the hinge unit3, the free ends322of the slit members320may be moved closer to each other, and the hinge unit3may be bent, to form the curved portion3ahaving a predetermined curvature as shown inFIG.13.

FIG.14is a plan view illustrating the hinge unit3that may limit the bending direction, according to another exemplary embodiment.FIG.15is an exploded perspective view illustrating the hinge unit3ofFIG.14, according to an exemplary embodiment. InFIGS.14and15, the gap-widening prevention members330are integrally formed with the slit members320. Referring toFIGS.14and15, a wing portion334is disposed on an end portion of the connection portion333that extends toward the slit member320-2from the inner surface320-1cof the slit member320-1. The recess320-2bin which the wing portion334is received, the slot320-2einto which the connection portion333is inserted, and the protrusion320-2fthat prevents the connection portion333from being separated from the slot320-2eare provided in the slit member320-2that is disposed adjacent to the slit member320-1. The connection portion333, the recess320-1b, the slot320-1e, and the protrusion320-1fthat prevents the connection portion from being separated from the slot320-1eare provided in a slit member that is disposed adjacent to the slit member320-1to be opposite to the slit member320-2. Also, the connection portion333and the wing portion332that are coupled to another adjacent slit member are provided in the slit member320-2.

In this configuration, the bending direction of the hinge unit3may be limited in the same manner as that described with reference toFIGS.8through13. Also, because the gap-widening prevention members330are integrally formed with the slit members320, the number of parts may be reduced, material costs may be reduced, the number of assembly processes may be reduced, and thus manufacturing costs may be reduced.

The gap-widening prevention members330are not limited toFIGS.8through15. For example, the gap-widening prevention members330may include wires.FIG.16is a perspective view illustrating the hinge unit3that may limit the bending direction, according to another exemplary embodiment. Referring toFIG.16, projections320-1hand320-2hare disposed on the outer surfaces320-1aand320-2aof the slit members320-1and320-2. The projections320-1hand320-2hmay extend downward after being bent in a “¬” shape from the free ends322of the slit members320-1and320-2. The projections320-1hand320-2hare connected to each other by using a wire330′. The wire330′ includes two looping portions331′ and332′ and a connection wire333′ that connects the looping portions331′ and332′. When the looping portions331′ and332′ that are disposed on both sides of the wire330′ are caught by the projections320-1hand320-2h, the free ends332of the slit members320-1and320-2may be restricted from being moved farther away from each other. Alternatively, the gap-widening prevention members may be implemented by using a second plurality of slit members as described above.

Referring toFIGS.2and3, the flexible display element4has no flexibility in length, a total length in the unfolded state ofFIG.2and a total length in the folded state ofFIG.3have to be substantially the same. However, because the first and second bodies1and2and the hinge unit3are disposed outside the flexible display element4in the folded state, a sum of lengths of outer walls of the hinge unit3and the first and second bodies1and2in the folded state has to be greater than a sum of lengths in the unfolded state. Because the first body1and the second body2are not flexible in general, a difference between the lengths of the outer walls in the unfolded state and the folded state may be compensated for by allowing the support member310of the hinge unit3to be formed of a flexible material having elasticity.

Alternatively, the difference between the lengths of the outer walls in the unfolded state and the folded state may be compensated for by allowing the hinge unit3and at least one of the first and second bodies1and2to be slid in the longitudinal direction L of the flexible display element4.FIG.17is an exploded perspective view illustrating the electronic device100in which the hinge unit3and the first and second bodies1and2are slidably connected to each other, according to an exemplary embodiment.FIG.18is a cross-sectional view taken along a line A-A′ ofFIG.17.FIG.19is a cross-sectional view taken along a line B-B′ ofFIG.17.

Referring toFIG.17, the first body1includes a first housing11that forms a portion of an outer appearance, and a first support plate12that is disposed on the first housing11and allows the first portion4aof the flexible display element4to be coupled thereto. The second body2includes a second housing21that forms another portion of the outer appearance, and a second support plate22that is disposed on the second housing21and allows the second portion4bof the flexible display element4to be coupled thereto. The hinge unit3is slidably coupled to each of the first and second housings11and21. The hinge unit3may include the support member310and the slit members320, or may include the support member310, the slit members320, and the gap-widening prevention members330.

Referring toFIGS.17and18, the support member310is supported by one pair of holders340that are disposed on both sides in the longitudinal direction L. Guide rails341that extend in the longitudinal direction L are disposed on the one pair of holders340. Sliding grooves13and23into which the guide rails341are slidably inserted are formed in the first and second bodies1and2. For example, portions12-1and22-1of the first and second support plates12and22may be spaced apart from inner surfaces of the first and second housings11and21, and the sliding grooves13and23may be formed between the inner surfaces of the first and second housings11and21and the portions12-1and22-1of the first and second support plates12and22.

Restriction units that restrict a sliding distance between the hinge unit3and the first and second bodies1and2may be further provided in order to prevent the first and second bodies1and2from being separated in the longitudinal direction L from the hinge unit3. Referring toFIGS.17and19, the restriction units may include, for example, stoppers342that are provided on the one pair of holders340and projecting ridges14and24that are disposed on the first and second bodies1and2and catch the stoppers342. The stoppers342may protrude upward from edges of the holders340. The projecting ridges14and24may protrude downward from the first and second support plates12and22.

In this configuration, when the hinge unit3is folded, because the first and second bodies1and2are guided through the guide rails341and the sliding grooves13and23and are slid in the longitudinal direction L, lengths of outer walls may be increased. Hence, the electronic device100may be folded using a small force as shown inFIG.3. Also, when the hinge unit3is completely folded, because the stoppers342are caught by the projecting ridges14and24, the first and second bodies1and2and the hinge unit3may be prevented from being separated from each other.

A structure in which the first and second bodies1and2and the hinge unit3are slidably connected to each other has been described. However, the present exemplary embodiment is not limited thereto, and the hinge unit3and any one of the first and second bodies1and2may be slidably connected to each other. However, when the first and second bodies1and2and the hinge unit3are slidably connected to each other, because lengths of outer walls of the hinge unit3and the first and second bodies1and2are more naturally increased, the electronic device100may be more naturally folded as shown inFIG.3.

The electronic device100may be stopped at a predetermined position between the unfolded state (seeFIG.2) and the completely folded state (seeFIG.3) as shown inFIG.20. That is, an unfolding angle AG between the first and second bodies1and2may be adjusted by slidably connecting the first and second bodies1and2and the hinge unit3and enabling the electronic device100to be temporarily stopped at a predetermined position during the sliding. The number of the predetermined position(s) at which the electronic device100is stopped may be one, or two or more. In this configuration, usability may be improved by using a user interface (UI) and a screen suitable for the unfolding angle AG. For example, the first portion4athat is supported by the first body1that is erected in the flexible display element4may be driven as an image display unit that displays an image, and the second portion4bthat is supported by the second body2that is laid down in the flexible display element4may be driven as an input unit that allows a key input.

FIG.21is an exploded perspective view illustrating the electronic device100in which the first and second bodies1and2and the hinge unit3are slidably connected to each other and the unfolding angle AG of the first and second bodies1and2may be adjusted, according to another exemplary embodiment.FIGS.22and23are respectively a perspective view and an exploded perspective view illustrating a sliding frame6and a sliding plate7, according to an exemplary embodiment. Referring toFIGS.21,22, and23, the sliding frame6, and the sliding plate7that is slidably coupled to the sliding frame6are illustrated. The sliding frame6is coupled to the first and second bodies1and2. For example, the sliding frame6may be coupled to each of the first and second support plates12and22. The sliding plate7is coupled to the hinge unit3. For example, the support member310may be supported by the one pair of holders340that are disposed on both sides in the longitudinal direction L, and the sliding plate7may be coupled to each of the holders340.

Guide rails71that extend in the longitudinal direction L are provided on both side portions of the sliding plate7. Guide grooves63into which the guide rails71are slidably inserted are formed in the sliding frame6. For example, the sliding frame6may include a first member61that has “[” shape portions62formed on both side portions of the first member61, and second members64that are disposed on the “[” shape portions62and include the guide grooves63. The second members64may be formed of a material having lubricating properties that may reduce contact resistance with the guide rails71. Examples of the material having lubricating properties may include an engineering plastic such as polyacetal, an oil-containing plastic, and a sintered metal. When the sliding plate7is slid relative to the sliding frame6, the first and second bodies1and2and the hinge unit3may be slidably coupled to each other.

Restriction units that restrict a sliding distance between the first and second bodies1and2and the hinge unit3are provided in order to prevent the first and second bodies1and2from being separated in the longitudinal direction L from the hinge unit3. For example, the restriction units may include stoppers72that are disposed on one end portion in a sliding direction of the sliding plate7(that is, the end portion opposite to a portion of the sliding plate7that is connected to the hinge unit3) and are caught by an end portion of the sliding frame6in the longitudinal direction L. The stoppers72may protrude outward from, for example, an edge of the sliding plate7in a width direction (perpendicular to the sliding direction).

The unfolding angle AG between the first and second bodies1and2may be adjusted as shown inFIG.20by enabling the sliding plate7to be stopped at a predetermined position while being slid relative to the sliding frame6. An unfolding angle adjustment unit that adjusts the unfolding angle AG between the first and second bodies1and2may include an angle adjustment slot65that is cut in the sliding direction, that is, the longitudinal direction L, of the flexible display element4and is formed in the sliding frame6, and an angle adjustment post73that is disposed on the sliding plate7and is inserted into the angle adjustment slot65. The angle adjustment slot65includes a plurality of locking portions65-1,65-2, and65-3that lock the angle adjustment post73, and concave portions65aand65bthat are disposed between the plurality of locking portions65-1,65-2, and65-3and have a slot width less than that of the plurality of locking portions65-1,65-2, and65-3. For example, the angle adjustment slot65may be formed of a material having elasticity, and may be disposed on an elastic member650that is coupled to the sliding frame6. Examples of the material having elasticity may include an engineering plastic such as polyacetal and an elastic metal such as a leaf spring.

In this configuration, when the angle adjustment post73is located at the first locking portion65-1, the sliding plate7is stopped and locked at a first position. The first position corresponds to the unfolded state (first state) of the first and second bodies1and2ofFIG.2. In the unfolded state, when the hinge unit3is slid relative to the first and second bodies1and2and lengths of outer walls of the hinge unit3and the first and second bodies1and2are increased, the hinge unit3is bent outward as shown inFIG.24. Accordingly, the third portion4cof the flexible display element4is not supported by the hinge unit3and a space between the third portion4cof the flexible display element4and the hinge unit3is widened. In this state, when a pressing force is applied to, for example, the third portion4cof the flexible display element4, the flexible display element4may be damaged. Also, when a touch panel function is added to the flexible display element4, a touch sensitivity of the third portion4cmay be degraded. In the present exemplary embodiment, in order for the angle adjustment post73to be moved from the first locking portion65-1to the second locking portion65-2, the angle adjustment post73has to pass through the concave portion65a. To this end, a force great enough for the angle adjustment post73to widen the concave portion65ahas to be applied to the first and second bodies1and2. Hence, unless the force is applied, the hinge unit3may not be slid relative to the first and second bodies1and2, the first and second bodies1and2may be maintained in the unfolded state ofFIG.2, and the flexible display element4may be stably supported by the hinge unit3.

When the angle adjustment post73is located at the third locking portion65-3, the sliding plate7is stopped and locked at a third position. The third position corresponds to the completely folded state (third state) of the first and second bodies1and2ofFIG.3.

Also, when the angle adjustment post73is located at the second locking unit65-2, the sliding plate7is stopped and locked at a second position. The second position corresponds to a state (second state) in which the first body1and the second body2form the unfolding angle AG as marked by a solid line ofFIG.20.

In this configuration, the first and second bodies1and2may be locked in the completely unfolded state, the completely folded state, and the state in which the unfolding angle AG is formed between the completely unfolded state and the completely folded state.

Although there is only one position between the completely folded state and the unfolded state, the present exemplary embodiment is not limited thereto. The first and second bodies1and2may be locked at two or more unfolding angles AG by locating a plurality of the second locking portions65-2between the first and second locking portions65-1and65-3.

According to an electronic device of the one or more exemplary embodiments, a flexible display element may be protected from being overly bent in a folding process. Because folding is allowed only in one direction, the flexible display element and the electronic device may be prevented from being damaged due to folding in the opposite direction. Because a hinge unit and two bodies are slidably connected to each other, natural (or easy) folding is possible. An unfolding angle between the two bodies may be adjusted by locking the hinge unit during sliding. Because the hinge unit is locked to prevent it from sliding relative to the two bodies in a completely unfolded state, the flexible display element may be stably supported in a state where the two bodies are completely unfolded.

While exemplary embodiments have been described with respect to a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope as disclosed herein. Accordingly, the scope should be limited only by the attached claims.