Patent Description:
Terminals may be generally classified as mobile/portable terminals or stationary terminals. Mobile terminals may also be classified as handheld terminals or vehicle mounted terminals.

A display device is equipped with functions of receiving, processing and displaying user-viewable images. The display device, for example, receives broadcasting selected by a user from broadcast signals broadcasted by a broadcasting station, splits video signals from the received signals, and displays the split video signals on a display.

Recently, owing to the developments of broadcast and network technologies, functions of a display device have been considerably diversified and performance of the device has been improved correspondingly. Namely, the display device has been developed so as to provide a user with various contents as well as simply broadcasted contents. For example, the display device can provide game play, listening to music, Internet shopping, user-customized information and the like using various applications as well as programs received from broadcasting stations. In order to perform such extended functions, the display device is basically connected to other devices or a network using various communication protocols and can provide ubiquitous computing environments to a user. Namely, the display device has been evolved into a smart device that enables connectivity to a network and ubiquitous computing.

Recently, a flexible display having sufficient elasticity to enable big deformation has been developed. The flexible display may be deformed to be rolled. A mobile terminal receives the rolled flexible display and may protrude the display to the outside of its body at a desired size. Therefore, the mobile terminal can have a more compact size in accordance with a use of the flexible display. Also, as the mobile terminal includes such a rollable display, the mobile terminal can be referred to as a rollable mobile terminal.

In order to use the rollable mobile terminal, a user can eject the display from a body of the mobile terminal and at the same time the display can be extended to a size desired by the user. However, the display may be extended to various directions by the user, and relative alignment or arrangement of the display for the user may be varied depending on the extended direction. Therefore, in order to allow the user to view intended contents or screen, the mobile terminal needs to align contents or screen on the display in consideration of the varied display or relative alignment of the user. Moreover, the mobile terminal additionally needs to adjust the aligned contents in consideration of the extended direction and alignment.

<CIT> discloses a slidable display capable of expanding a screen. The display includes a roller at an end of a bottom cover, which is movable relative to a top cover. The display rolls around the roller and is supported by the top cover and/or the bottom cover in different states.

<CIT> discloses a sliding mechanism used for a portable electronic device with two or more housings.

<CIT> discloses a display including a plurality of support slats as a support mechanism moving around a chain wheel.

<CIT> discloses a mobile terminal unit by which a pullout display to be pulled out from a body is utilized efficiently. The mobile terminal includes two rollers that are at the same housing and configured to maintain the tension of the display.

<CIT> discloses a mobile device including housing parts that slide-engage relative to each other to extend and retract the device. The mobile device includes a plurality of rollers that are placed at the same housing and configured for maintaining the tension of the display.

Accordingly, an object of the present invention is to address the above-noted and other problems and provide a roll-slide mobile terminal capable of improving durability of a flexible display unit as a point where the flexible display unit is folded is limited to a specific position.

Another object of the present invention is to provide a roll-slide mobile terminal including a support structure of a flexible display unit, in which the flexible display unit may stably be supported when it is extended.

A further object of the present invention is to provide a roll-slide mobile terminal including a drive unit configured to guide the movements of a frame and a flexible display unit in communication which can prevent a corrugation generated in the flexible display unit separated from the frame, when the roll-slide mobile terminal is transited from a second state to a first state.

A sill further object of the present invention is to provide a roll-slide mobile terminal that prevents a flexible display unit from being damaged by external impact at a side where the flexible display is folded.

A roll-slide mobile terminal according to the present invention is set forth in claim <NUM>. Preferred embodiments of the present invention are provided in dependent claims.

The area of the front surface of the roll-slide mobile terminal that is occupied by the flexible display unit may be larger in the second state than the first state.

The first frame may comprise an edge portion to which one end of the flexible display unit is coupled; and a middle portion in which the drive unit is provided.

The second frame may comprise a flat portion provided on a front surface of the middle portion; and a bending portion provided in the second direction of the flat portion and configured to be partially located on a rear surface of the middle portion even when bending.

The bending portion may comprise a plurality of support bars extended in a third direction that is perpendicular to the first direction and arranged in parallel with the second direction.

The bending portion may slide along a rail formed in the first frame.

The roll-slide mobile terminal further comprises a second roller coupled to the first frame and having the bending portion rolled there around.

The first frame may comprise a gap formed between the edge portion and the middle portion, with the bending portion penetrating there through.

The drive unit may comprise a first drive unit arranged in a rear surface of the middle portion and configured to guide the first and second direction movements of the second frame.

The drive unit may comprise a first control bar having a center rotatably coupled to the first frame; a first slide slot extended from one end of the bending portion in a third direction that is perpendicular to the first direction and configured to insert a first slide projection, that is projected from one end of the first control bar, therein; and a second slide slot extended from the flat portion in the third direction and configured to insert a second slide projection, that is projected from the other end of the first control bar, therein.

The first drive unit may further comprise a third slide slot formed in the first frame in an arc shape with respect the center of the first control bar, and the second slide projection may be coupled to the second slide slot through the third slide slot.

The roll-slide mobile terminal may further comprise a securing slot extended from the first-direction end of the third slide slot in a third direction, wherein the second slide projection is located in the securing slot in the second state.

The second drive unit may comprise a second drive unit provided in a front surface of the middle portion and configured to guide the first and second direction movements of the third frame.

The second drive unit may comprise a fourth slide slot extended in a third direction that is perpendicular to the first direction and formed in the third frame; and a second control bar having one end rotataly coupled to the middle portion and a third slide projection projected from the other end, and the third slide projection may be inserted in the fourth slide slot to slide.

The second drive unit may further comprise an elastic unit having one end fixed to the first or second frame and the other end connected with the second control bar or the third frame, and the elastic unit may provide a predetermined elasticity to pull the third frame in the second direction when the roll-slide mobile terminal is transited from the second state to the first state.

The first frame may further comprise a rear portion configured to cover a rear surface of the bending portion.

The roll-slide mobile terminal may further comprise a third roller provided adjacent to the first roller in the second direction and configured to support the flexible display unit located on the rear surface of the roll-slide mobile terminal.

The flexible display unit may comprise a display panel; and a back plate configured to support a rear surface of the display panel and coupled to the first frame and the third frame.

Since the roll-slide mobile terminal of the present invention does not limit a point where the flexible display unit is folded to a specific position, durability of the flexible display unit may be improved. Also, since the flexible display unit may stably be supported when it is extended, it is possible to minimize difficulty in a touch input. Also, the flexible display unit from may be prevented from being damaged by external impact at a side where the flexible display is folded.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by illustration only, since various changes and modifications within the scope of the invention defined by the claims will become apparent to those skilled in the art from this detailed description.

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings, which are given by illustration only, and thus are not limitative of the present invention, and wherein:.

Description will now be given in detail according to exemplary embodiments disclosed herein, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components may be provided with the same reference numbers, and description thereof will not be repeated. In general, a suffix such as "module" and "unit" may be used to refer to elements or components. Use of such a suffix herein is merely intended to facilitate description of the specification, and the suffix itself is not intended to give any special meaning or function. The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings.

When an element is referred to as being "connected with" another element, the element can be directly connected with the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly connected with" another element, there are no intervening elements present.

The mobile terminal <NUM> is shown having components such as a wireless communication unit <NUM>, an input unit <NUM>, a sensing unit <NUM>, an output unit <NUM>, an interface unit <NUM>, a memory <NUM>, a controller <NUM>, and a power supply unit <NUM>. Implementing all of the illustrated components in The Fig. 1A is not a requirement, and that greater or fewer components may alternatively be implemented.

The mobile communication module <NUM> can transmit and/or receive wireless signals to and from one or more network entities. Typical examples of a network entity include a base station, an external mobile terminal, a server, and the like. Such network entities form part of a mobile communication network, which is constructed according to technical standards or communication methods for mobile communications (for example, Global System for Mobile Communication (GSM), Code Division Multi Access (CDMA), CDMA2000 (Code Division Multi Access <NUM>), EV-DO (Enhanced Voice-Data Optimized or Enhanced Voice-Data Only), Wideband CDMA (WCDMA), High Speed Downlink Packet access (HSDPA), HSUPA (High Speed Uplink Packet Access), Long Term Evolution (LTE) , LTE-A (Long Term Evolution-Advanced), and the like).

Examples of such wireless Internet access include Wireless LAN (WLAN), Wireless Fidelity (Wi-Fi), Wi-Fi Direct, Digital Living Network Alliance (DLNA), Wireless Broadband (WiBro), Worldwide Interoperability for Microwave Access (WiMAX), High Speed Downlink Packet Access (HSDPA), HSUPA (High Speed Uplink Packet Access), Long Term Evolution (LTE), LTE-A (Long Term Evolution-Advanced), and the like.

In some embodiments, when the wireless Internet access is implemented according to, for example, WiBro, HSDPA, HSUPA, GSM, CDMA, WCDMA, LTE, LTE-A and the like, as part of a mobile communication network, the wireless Internet module <NUM> performs such wireless Internet access.

Suitable technologies for implementing such short-range communications include BLUETOOTHTM, Radio Frequency IDentification (RFID), Infrared Data Association (IrDA), Ultra-WideBand (UWB), ZigBee, Near Field Communication (NFC), Wireless-Fidelity (Wi-Fi), Wi-Fi Direct, Wireless USB (Wireless Universal Serial Bus), and the like.

Cameras <NUM> may process image frames of still pictures or video obtained by image sensors in a video or image capture mode. The processed image frames can be displayed on the display unit <NUM> or stored in memory <NUM>. In some cases, the cameras <NUM> may be arranged in a matrix configuration to permit a plurality of images having various angles or focal points to be input to the mobile terminal <NUM>. As another example, the cameras <NUM> may be located in a stereoscopic arrangement to acquire left and right images for implementing a stereoscopic image.

Further, the virtual key or the visual key may be displayed on the touch screen in various shapes, for example, graphic, text, icon, video, or a combination thereof.

The sensing unit <NUM> is typically implemented using one or more sensors configured to sense internal information of the mobile terminal, the surrounding environment of the mobile terminal, user information, and the like. For example,, the sensing unit <NUM> may alternatively or additionally include other types of sensors or devices, such as a proximity sensor <NUM> and an illumination sensor <NUM>, a touch sensor, an acceleration sensor, a magnetic sensor, a G-sensor, a gyroscope sensor, a motion sensor, an RGB sensor, an infrared (IR) sensor, a finger scan sensor, a ultrasonic sensor, an optical sensor (for example, camera <NUM>), a microphone <NUM>, a battery gauge, an environment sensor (for example, a barometer, a hygrometer, a thermometer, a radiation detection sensor, a thermal sensor, and a gas sensor, among others), and a chemical sensor (for example, an electronic nose, a health care sensor, a biometric sensor, and the like), to name a few. The mobile terminal <NUM> may be configured to utilize information obtained from sensing unit <NUM>, and in particular, information obtained from one or more sensors of the sensing unit <NUM>, and combinations thereof.

The controller <NUM> typically functions to control overall operation of the mobile terminal <NUM>, in addition to the operations associated with the application programs. The controller <NUM> can provide or process information or functions appropriate for a user by processing signals, data, information and the like, which are input or output, or activating application programs stored in the memory <NUM>.

To drive the application programs stored in the memory <NUM>, the controller <NUM> can be implemented to control a predetermined number of the components mentioned above in reference with FIG. Moreover, the controller <NUM> can be implemented to combinedly operate two or more of the components provided in the mobile terminal <NUM> to drive the application programs.

Next, <FIG> is a perspective view illustrating a first state and a second state when a roll-slide mobile terminal according to an embodiment of the present invention is viewed at one side, and <FIG> is a rear view illustrating a first state and a second state of a roll-slide mobile terminal according to an embodiment of the present invention. In particular, <FIG> and <FIG> illustrate a first state of the roll-slide mobile terminal <NUM> according to one embodiment of the present invention, and <FIG> and <FIG> illustrate a second state of a roll-slide mobile terminal <NUM> according to one embodiment of the present invention.

As shown, the roll-slide mobile terminal <NUM> of the first state has a size smaller than that of the roll-slide mobile terminal <NUM> of the second state in a first direction. In the roll-slide mobile terminal <NUM> of the second state, the size of the first direction is extended and a size of a display unit <NUM> arranged on a front surface becomes greater than the first state. In addition, a direction along which the roll-slide mobile terminal <NUM> is extended is referred to as a first direction, a direction along which the roll-slide mobile terminal <NUM> is contracted to be shifted from the second state to the first state is referred to as a second direction, and a direction vertical to the second direction is referred to as a third direction.

In a first state of the roll-slide mobile terminal <NUM> according to an embodiment of the present invention like a bar-type mobile terminal, a screen is expanded and changed into a second state. In the second state, the area of the display unit <NUM> arranged in the front surface is expanded in a first direction and the area of the display unit arranged in the rear surface as shown in <FIG> is reduced. In other words, the display unit located in the rear surface in the first state is moved towards the front surface in the second state. For easy and convenient description sake, the area of the display unit <NUM> that is located in the front surface of the roll-slide mobile terminal <NUM> is defined as the first area and the area located in the rear surface of the roll-slide mobile terminal <NUM> is defined as the second area. The first area and the second can be changed based on the current state of the roll-slide mobile terminal <NUM>.

In this way, a flexible display unit <NUM> which is bent may be used as the display unit such that the position of the display unit can be varied. In more detail, the flexible display means a display, which is manufactured on a thin and flexible substrate capable of being curved, bent, folded, twisted or rolled like a paper, and is lightweight and robust not to be easily broken while maintaining characteristics of the existing flat panel display.

Also, an electronic paper is based on a display technique to which a feature of a general ink is applied, and is different from the existing flat panel display in that it uses reflective light. The electronic paper can change information by using electrophoresis that uses a twist ball or capsule.

When the flexible display unit <NUM> is not deformed (for example, the state that the flexible display unit <NUM> has an infinite curvature radius, hereinafter, referred to as base state), a display area of the flexible display unit <NUM> becomes a plane. In a state (for example, the state having a finite curvature radius, hereinafter, referred to as a deformation state) deformed by an external force from the base state, the display area has a curved surface. As shown, information displayed in the deformation state may be visual information output to the curved surface. This visual information is implemented as luminescence of unit sub-pixels arranged in a matrix arrangement is controlled independently. The unit sub-pixel means a minimum unit for implementing one color.

In addition, the flexible display unit <NUM> can be arranged in a bent state (for example, the state bent in a vertical or horizontal direction) not a flat state in the base state. In this instance, if an external force is applied to the flexible display unit <NUM>, the flexible display unit <NUM> can be deformed in a flat state (or less bent state) or a more bent state.

Further, the flexible display unit <NUM> may implement a flexible touch screen in combination with a touch sensor. If a touch is performed for a flexible touch screen, the controller <NUM> can perform a control corresponding to such a touch input. The flexible touch screen may be configured to sense a touch input even in the deformation state as well as the base state.

In addition, the touch sensor senses a touch (or touch input) applied to the touch screen by using at least one of various touch modes such as a resistive film mode, a capacitance mode, an infrared mode, an ultrasonic mode, and a magnetic field mode. As an example, the touch sensor can be configured to convert a change of a pressure applied to a specific portion of the touch screen or a change of capacitance occurring in the specific portion to an electric input signal. The touch sensor can also be configured to allow a touch target, which performs a touch on the touch screen, to detect a touch position, a touch area, a touch pressure and touch capacitance on the touch sensor.

Further, the roll-slide mobile terminal <NUM> according to this modified embodiment may include a deformation sensing mechanism capable of sensing deformation of the flexible display unit <NUM>. The deformation sensing mechanism may be included in the sensing unit <NUM>.

The deformation sensing mechanism may be provided in the flexible display unit <NUM> or a case <NUM> to sense information related to deformation of the flexible display unit <NUM>. In this instance, the information related to deformation may include a direction of the flexible display unit <NUM> which is modified, a modified level, a modified position, a modified time and restored acceleration of the deformed flexible display unit <NUM>. In addition, the information related to deformation may include various kinds of information to be sensed by bending of the flexible display unit <NUM>.

Also, the controller <NUM> can modify information displayed on the flexible display unit <NUM> or generate a control signal for controlling functions of the roll-slide mobile terminal <NUM>, based on the information related to deformation of the flexible display unit <NUM> sensed by the deformation sensing means. State deformation of the flexible display unit <NUM> is not limited to deformation caused by an external force. For example, when the flexible display unit <NUM> has the first state, the first state can be modified to the second state by a command of a user or an application. In this way, in order that the flexible display unit <NUM> is modified without external force, the flexible display unit <NUM> may include a driving unit.

In addition, the flexible display unit <NUM> may be bent <NUM> degrees. Some area of the flexible display unit <NUM> may also be positioned on the front surface and the other area may be positioned on the rear surface of the roll-slide mobile terminal <NUM>. The overall area of the flexible display unit <NUM> is fixed such that the extent of the area located in the rear surface (the second area) may decrease if the extent of the area located in the front surface (the first area) increases.

Next, <FIG> is an exploded perspective view of the roll-slide mobile terminal 100viewed in a front direction, and <FIG> is an exploded perspective view of the roll-slide mobile terminal 100viewed in a rear direction. As shown in <FIG> and <FIG>, the roll-slide mobile terminal <NUM> includes a first frame <NUM>; a second frame <NUM> that can slide with respect to the first frame <NUM>; and a third frame <NUM> that can slide in a first direction with respect to the second frame <NUM>.

The first frame <NUM> is provided as a basic frame of the roll-slide mobile terminal <NUM>. One end of the flexible display unit <NUM> is coupled to the first frame <NUM> and a drive unit configured to guide the sliding movement of the second and third frames <NUM> and <NUM> is coupled to the first frame <NUM>. As shown in <FIG>, the first frame <NUM> may include an edge portion <NUM> provided in a predetermined edge area of the mobile terminal; and a middle portion <NUM> formed in a plate shape. The middle portion <NUM> and the edge portion <NUM> may be integrally formed with each other or coupled to each other by an auxiliary member. The edge portion <NUM> may be provided in a second-direction end of the roll-slide mobile terminal <NUM> and the middle portion <NUM> may form a flat plate. The edge portion <NUM> may be exposed outside and the middle portion <NUM> may be covered by flexible display unit <NUM> and the second frame <NUM> not to be exposed outside.

As shown in <FIG>, the first frame <NUM> may also include a side portion <NUM> defining a lateral surface of the mobile terminal <NUM>. The interface unit, the user input unit and a USIM card inserting slot may be arranged in the side portion <NUM>. An antenna can also be realized by using the side portion <NUM>.

Further, the second frame <NUM> is coupled to the first frame <NUM> and slides in the first or second direction. As shown, the second frame <NUM> may include a flat portion <NUM> provided in a front surface of the middle portion <NUM> of the first frame; and a bending portion <NUM> that is bendable at the flat portion <NUM> in the second direction. The bending portion <NUM> may be insertedly bendable towards a rear surface of the middle portion <NUM>.

Next, <FIG> is a cross-sectional view taken along line A-A of <FIG>, and <FIG> is a cross-sectional view taken along line B-B of <FIG>. The bending portion <NUM> may be movable from the front surface towards the rear surface or vice versa based on the current state of the mobile terminal <NUM>. Accordingly, the bending portion <NUM> occupies a large area on the rear surface of the middle portion <NUM> in the first state and a large area on the front surface of the middle portion <NUM> in the second state. The flat portion <NUM> may be always located on the front surface of the middle portion <NUM> and the bending portion <NUM> may be located on the front or rear surface of the middle portion <NUM> based on the state of the mobile terminal.

The bending portion <NUM> may be configured of a plurality of support bars 1022a (see <FIG>) extended in a third direction that is perpendicular to the first direction. The support bars 1022a may have a predetermined thickness or be bent to enhance the strength. The support bars may also be partially rolled in a ring shape and a hinge pin may be inserted in a rolled area to couple each two neighboring support bars 1022a. Each support bar 1022a may be rotatable with respect to its neighboring support bar and the hinge pin such that an angle between each two neighboring support bars 1022a is variable. Accordingly, the bending portion <NUM> can be bent to overlap with the front surface and the rear surface.

A slide portion <NUM> may be further provided in one end of the bending portion <NUM> to guide the sliding movement of the bending portion <NUM>. A slide slot <NUM>, to which one end 211b of a first control bar of the first drive unit which will be described later is coupled, is formed in the slide portion <NUM> such that the slide portion <NUM> can guide the sliding movement of the second frame <NUM>.

The slide portion <NUM> may be one end of the bending portion such that it may move in the reverse direction, compared with the moving direction of the flat portion <NUM>. When the first state is changed into the second state in the roll-slide mobile terminal <NUM>, the flat portion <NUM> moves in the first direction and the slide portion <NUM> moves in the second direction. At this time, the bending portion <NUM> may occupy a larger area on the front surface of the middle portion <NUM>.

In addition, the flexible display unit <NUM> may have one end coupled to the first frame <NUM> and be extended in the first direction that is the reverse direction of the bending portion <NUM> provided in the second frame <NUM>. The flexible display unit <NUM> can be bent with rolling a first roller <NUM> coupled to the flat portion <NUM> and then extended towards the rear surface of the flat portion <NUM>. The other end of the flexible display unit <NUM> is located on the rear surface of the flat portion <NUM> and coupled to the third frame <NUM> so as to slide in the first and second directions.

Referring to <FIG> and <FIG>, the third frame <NUM> and the flexible display unit <NUM> may be located on the front surface of the middle portion <NUM> of the first frame <NUM> and the rear surface of the flat portion of the second frame <NUM>, respectively. The slide portion <NUM> located in the end of the bending portion <NUM> may be located on the rear surface of the middle portion <NUM>.

Referring to <FIG>, the layer structure in the first state may be configured of the first area of the flexible display unit <NUM>. The flat portion <NUM>, the second area and the third frame <NUM> of the flexible display unit <NUM>, the middle portion <NUM> of the first frame, the bending portion <NUM>, the slide portion <NUM> and the rear portion <NUM> of the first frame defining the rear surface that is located in the most backward direction from the front surface.

Referring to <FIG>, one end of the flexible display unit <NUM> coupled to the middle portion <NUM> and the edge portion <NUM> of the first frame <NUM>, the rear portion <NUM> and the second roller <NUM> having the bending portion <NUM> rolled there around are located on the left side shown in the drawing in the second state. The flat portion <NUM> of the second frame, the first roller <NUM> and the third roller <NUM>, and the third frame <NUM> move to right side.

The flexible display unit <NUM> may include a display panel 151b configured to output an image; and a back plate 151c configured to support a rear surface of the display panel 151b.

The display panel 151b may be a flexible image display device (e.g., OLED). The back plate 151c may be provided in the rear surface of the display p0anel 151b and a metal plate that is bendable together with the display panel 151b when it is bending, with a predetermined strength enough to support the display panel 151b.

Further, the back plate 151c and the display panel 151b may be bonded to each other, using an adhesive material. Examples of the adhesive material may include a double-sided tape (e.g., OCA) that is extendible in a preset range such as a foam material. Accordingly, the adhesive material may offset a slip phenomenon that might be caused by a difference between the curvature radius of the back plate 151c and that of the display panel 151b.

A groove may also be formed in a surface of the bending area of the back plate 151c in the third direction to naturally facilitate the bending, when the flexible display panel <NUM> is bending. In addition, the bending portion <NUM> and the flexible display unit <NUM> are rolled in the reverse directions. When the current state of the roll-slide mobile terminal is changed into the first state or second state, the slide portion <NUM> located in the end of the bending portion <NUM> and the third frame <NUM> located in the end of the flexible display unit <NUM> moves in the reverse directions. Specifically, when the first state is changed into the second state, the third frame <NUM> moves in the first direction and occupy a larger area of the front surface of the flexible display panel <NUM> provided in the mobile terminal <NUM>.

A first roller <NUM> may be further provided in the second frame <NUM> and configured to have the flexible display unit <NUM> rolled there around. Also, a second roller <NUM> may be further provided in the first frame <NUM> and have the bending portion <NUM> rolled there around. As shown in <FIG>, the second roller <NUM> may be located in a gap <NUM> formed between the edge portion <NUM> and the middle portion <NUM> and rotatably coupled to the first frame <NUM>. The first roller <NUM> and the second roller <NUM> may also be rotated in the reverse directions. When the second area of the flexible display unit <NUM> is moved in the first direction, the end of the bending portion <NUM> also moves in the reverse direction (the second direction).

Further, the bending portion <NUM> is advantageous so as to provide a structure that supports the expanded first area when the current state of the roll-slide mobile terminal <NUM> is changed into the second state. Unless the bending portion <NUM> is provided as shown in <FIG>, an empty space might be generated in the rear surface of the first area of the flexible display unit <NUM> supported by the second frame <NUM> moving in the first direction and the empty space might cause corrugation in the flexible display unit <NUM>.

Even if a support structure is provided in the rear surface of the second frame <NUM>, the empty space as large as the thickness of the second frame <NUM> might be generated to cause deflection in the display unit. accordingly, as shown in <FIG>, the second frame <NUM> may be configured to keep the height of one surface, that contacts with the rear surface of the flexible display unit <NUM>, equal to the heights of the flat portion <NUM> and the bending portions <NUM> such that in the second state, the bending portion <NUM> can support the first area supported by the flat portion <NUM> in the first state.

In addition, the bending portion <NUM> may be movable along a rail <NUM> formed in the first frame <NUM>. As shown in <FIG>, the rail <NUM> may be provided in both sides of the middle portion <NUM> provided in the first frame <NUM> and have a corresponding width to the thickness of the bending portion <NUM>, with a groove shape extended in the first direction. The rail <NUM> may be formed in an inner surface of the side portion defining the lateral surface of the first frame <NUM>. The rail <NUM> may be configured to guide the first-direction movement of the bending portion <NUM> so as to prevent the deflection of the bending portion <NUM>.

The first frame <NUM> may further include a rear portion <NUM> defining an external design of the rear surface as shown in <FIG>. The rear portion <NUM> may form the external rear design of the roll-slide mobile terminal <NUM> and cover the drive unit and the bending portion <NUM> of the second frame <NUM> not to expose the drive unit to the rear surface in the first state.

The drive unit may include a first drive unit <NUM> configured to guide the sliding movement of the third frame <NUM> coupled to the other end of the flexible display unit <NUM>; and a second drive unit <NUM> configured to guide the sliding movement of the bending portion <NUM>. The first and second drive units may be arranged in both sides of the first frame <NUM> to realize the reverse-direction movements with respect to the first frame <NUM> coupled thereto. The first drive unit <NUM> may be arranged in a front surface of the first frame and the second drive unit <NUM> may be arranged in a rear surface of the first frame <NUM>. Accordingly, the third frame <NUM> coupled to the first drive unit <NUM> may be located on the front surface of the first frame <NUM> and one end of the bending portion <NUM> may be located on the rear surface of the first frame <NUM>.

To locate the other end of the flexible display unit <NUM> on the front surface of the first frame <NUM>, the distance between the first and second areas of the flexible display unit <NUM> has to be narrow. In other words, to space the first and second areas a distance as far as the thickness of the flat portion <NUM> of the second frame <NUM>, the curvature of the bending flexible display unit <NUM> has to be very small disadvantageously. As the curvature of the bending flexible display unit <NUM> is getting smaller, the stress applied to the flexible display unit <NUM> is getting larger enough to heighten the possibility of damage to the flexible display unit <NUM>.

Accordingly, the roll-slide mobile terminal <NUM> may further include a third roller <NUM> configured to support the second area to bend towards the front surface so as to narrow the distance between the first area and the second area even though the flexible display unit <NUM> is bending along a gentle curve.

A roll cover <NUM> may be further provided to cover the third roller <NUM> and allow the user to pull the second frame <NUM> in the first direction. The roll cover <NUM> shown in <FIG> may define the rear portion <NUM> of the first frame <NUM> and the rear surface of the roll-slide mobile terminal <NUM>. It is shown in the drawing that the roller cover <NUM> is located on the rear surface of the roll-slide mobile terminal <NUM> but the roll cover may be extended even to the lateral surface to protect the curved area of the flexible display unit <NUM> rolled around the first roller <NUM>.

When the roll-slide mobile terminal <NUM> is transited from the first state into the second state, the flat portion <NUM> of the second frame <NUM> is moving in the first direction and the slide portion <NUM> of the second frame <NUM> is moving in the second direction. The flat portion <NUM> located on the front surface of the middle portion <NUM> of the first frame <NUM> and the slide portion <NUM> located on the rear surface of the middle portion <NUM> of the first frame <NUM> may move the same distance in the reverse directions, respectively. The first <NUM> may be provided to synchronize the moving distance of the flat portion <NUM> and the moving distance of the slide portion so as to perform such symmetric movement stably. The first drive unit <NUM> may be configured to guide the flat portion <NUM> and the slide portion <NUM> to move the same distances in the reverse directions, respectively.

Next, <FIG> is a diagram illustrating the first drive unit <NUM> provided in the roll-slide mobile terminal <NUM>. In particular, <FIG> is a sectional diagram along C-C of <FIG> and <FIG> is a sectional diagram along D-D of <FIG> as a view illustrating a state where only the rear portion <NUM> of the first frame <NUM> is removed from a state viewing the rear surface of the mobile terminal <NUM> of <FIG>. In the first state, the first drive unit <NUM> is hidden by the bending portion <NUM> of the second frame <NUM> and is shown as a dotted line.

The first drive unit <NUM> includes a first control bar <NUM> provided in a rear surface of the middle portion <NUM> provided in the first frame <NUM>. The first control bar <NUM> has a center 211a rotatably coupled to a center of the middle portion <NUM> of the first frame <NUM>. One end 211b of the first control bar is coupled to the slide portion <NUM> of the second frame <NUM> and the other end 211c is coupled to the flat portion <NUM>. When the first state is transited into the second state in the mobile terminal <NUM>, the flat portion <NUM> is moving from the front surface of the middle portion <NUM> in the first direction and the slide portion <NUM> is moving from the rear surface of the middle portion <NUM> in the second direction. In other words, the moving directions of the flat portion <NUM> and the slide portion <NUM> are reverse such that the first controller bar <NUM> is rotatable on the center 211a rotatably coupled to the middle portion <NUM>.

In the control bar <NUM>, a distance from the coupled center 211a to the end 211b may be equal to a distance from the coupled center 211a to the other end 211c. The end 211b and the other end 211c of the control bar <NUM> moves in arcs when the first control bar <NUM> is rotated such that the third-direction positions of the ends are changed based on the angle of the first control bar <NUM>. To compensate a difference between the rotational movement and the linear movement, a first slide slot <NUM> may be extended in the third direction from the slide portion <NUM> to which the end of the first control bar is coupled and a second slide slot <NUM> may be extended in the third direction from the flat portion <NUM> to which the other end 211c of the first control bar is coupled.

In addition, the first slide slot <NUM> is coupled to the first control bar <NUM> towards the front surface and the second slide slot <NUM> is coupled thereto towards the rear surface. The first slide slot <NUM> and the second slide slot <NUM> may be as long as a distance where the first control bar <NUM> moves in the third direction when the first state is transited into the second state.

As the flat portion <NUM> is directed to the front surface of the middle frame, a third slide slot <NUM> may be formed in the middle potion <NUM> in an arc shape as shown in <FIG>, so as to couple the flat portion <NUM> and the first control bar <NUM> to each other. The other end 211c of the first control bar may be inserted in the second slide slot <NUM> of the flat portion <NUM> through the third slide slot <NUM>.

The third slide slot <NUM> may further include a securing slot 225a (see <FIG>) extended from the area, where the other end 211c of the first control bar is located in the second state, in the third direction as shown in <FIG>. The securing slot 225a restricts the rotation of the first control bar <NUM> to secure the second state transited by the user pulling the second frame <NUM> in the first direction. A ribbon-shaped groove <NUM> may be formed in the middle portion <NUM> to guide the rotation of the first control bar <NUM> as shown in <FIG>.

Next, <FIG> is a diagram illustrating the second drive unit <NUM> provided in the roll-slide mobile terminal <NUM>. While the flat portion <NUM> of the second frame <NUM> is moving in the first direction, the first area of the flexible display unit <NUM> is expanded and the third frame <NUM> to which the other end of the flexible display unit <NUM> is coupled is moving in the first direction. The second drive unit <NUM> may be configured to guide the first-direction movement of the third frame <NUM>. The second drive unit may include a second control bar <NUM> and a fourth slide slot <NUM>.

In particular, <FIG> is a sectional diagram along E-E of <FIG> and <FIG> is a sectional diagram along F-F illustrating only a member located towards the front surface of the middle portion <NUM>. One end 221a of the second control bar is rotatably coupled to the middle portion <NUM> and the other end 221b thereof is coupled to the fourth slide slot <NUM> formed in the third frame <NUM>. When the second control bar <NUM> is rotated on the end 221a coupled to the middle portion <NUM>, the other end 221b is moving in arcs. During the moving of the other end 221b of the second control bar, only the first and second direction moving may affect the third frame <NUM> and the third direction moving may use the fourth slide slot <NUM> extended in the third direction for the offsetting of the movement. When a state of <FIG> is transited to a state of <FIG> or vice versa in the second control bar <NUM>, the other end 221b is moving along the fourth slide slot <NUM> formed in the third frame <NUM>.

When the first state is transited into the second state, the user pulls the second control bar in a direction where the first and second frames <NUM> and <NUM> are spaced apart and the flat portion <NUM> of the second frame <NUM> moves in the first direction, while the slide portion <NUM> and the third frame <NUM> moves in the second direction and the first direction, respectively. At this time, the state shown in <FIG> is naturally transited into <FIG> state in the second control bar <NUM>.

In contrast, when user pushes the second frame <NUM> to the first frame <NUM>. In other words, pushing the second frame <NUM> in the second direction, the second area of the flexible display unit <NUM> has to be wide and the third frame <NUM> has to move in the second direction accordingly. When the flat portion <NUM> of the second frame <NUM> moves in the second direction, the first control bar <NUM> is rotated as shown in <FIG> from a state shown in <FIG>. At this time, the other 3end 211c of the first control bar is rotated in the second direction to pull the other end 221b of the second control bar.

Specifically, the force used in pulling the second control bar <NUM> in the second direction is needed to move it in the direction where the second area of the flexible display unit <NUM> is getting wide when the first state is transited to the second state. The sliding movement of the third frame <NUM> could be facilitated by using electric power of a motor. However, one embodiment of the present invention may provide an elastic unit <NUM> configured to support the rotational movement of the second control bar <NUM>, without the motor.

As shown in <FIG>, the elastic unit according to the embodiment may be a coil spring <NUM> having one end 225a coupled to the first frame <NUM> and the other end 225b coupled to the second control bar <NUM>. To make the coil spring tensile, a predetermined force is needed and a tensile spring may be used for that tensile. When the user pulls the second frame <NUM> in the first direction to transit the first state into the second state, the third frame <NUM> also moves in the first direction and the coil spring is lengthened to be given tension.

Once the first control bar <NUM> is secured to the securing slot 214a mentioned above, the second state is secured and the coil spring <NUM> is secured in a state of being tensioned. When the user transits the second state into the first state of the roll-slide mobile terminal <NUM> by pushing the second frame <NUM> in the second direction, the first control bar <NUM> is separated from the securing slot 214a and rotated along the third slide slot <NUM>. Hence, the second control bar <NUM> is rotated by the elasticity of the elastic unit <NUM> as shown in <FIG> and FIG. <NUM> (c) to move the third frame <NUM> in the second direction.

Next, <FIG> and <FIG> are diagrams illustrating another embodiment of the second drive unit <NUM> provided in the roll-slide mobile terminal <NUM>. The elastic unit <NUM> of the second drive unit <NUM> may be configured to apply an elastic force to rotate the second control bar <NUM> when the mobile terminal is switched from the second state into the first state.

Rather than the above-noted coil spring <NUM>, a torsion spring <NUM> may be used as shown in <FIG>. The torsion spring <NUM> may have one metal fan-shaped end 225a and the other end 225b that form a preset angle, with a coil wounded around the spring between the ends, and be configured to provide a predetermined elasticity applied to restore the angle between the ends in a preset angle. The ends of the torsion spring <NUM> are arranged at a preset angle in the first state of the mobile terminal <NUM>. One end is coupled to the first frame <NUM> and the other end is coupled to the second control bar <NUM>. When the user pushes the second frame <NUM> in the second direction in the second state of the mobile terminal, the first control bar <NUM> is released from the securing slot 214a and the second control bar <NUM> is rotated by the elasticity of the torsion spring <NUM>. After that, the third frame <NUM> is moved in the second direction and the roll-slide mobile terminal <NUM> is transited into the first state as shown in <FIG>.

<FIG> shows one embodiment using a compound spring <NUM>. The elastic unit <NUM> is not limited to the specific types such as the coil spring <NUM> or the torsion spring <NUM> but it may be diverse types. As shown in <FIG>, one end the other end of the elastic unit <NUM> may be coupled to the second frame <NUM> and the third frame <NUM>, respectively, as shown in <FIG>. In other words, the elastic unit <NUM> may be the member configured to provide a predetermined force for moving the third frame <NUM> with respect to the second frame <NUM> or the first frame <NUM> in the second direction such that one end 225a thereof may be coupled to the first frame <NUM> or the second frame <NUM> and the other end 225b thereof may be coupled to the second control bar <NUM> or the third frame <NUM>.

As described above, since the roll-slide mobile terminal of the present invention does not limit a point where the flexible display unit <NUM> is folded to a specific position, the durability of the flexible display unit <NUM> is improved. Also, since the flexible display unit <NUM> can stably be supported when it is extended, it is possible to minimize the difficulty in a touch input. Further, the flexible display unit <NUM> can be prevented from being damaged by external impact at the side where the flexible display unit <NUM> is folded.

Claim 1:
A roll-slide mobile terminal comprising:
a first frame (<NUM>);
a second frame (<NUM>) configured to slide with respect to the first frame (<NUM>) in a first direction along which the roll-slide mobile terminal is extended or a second direction opposite the first direction;
a first roller (<NUM>) provided in a first end of the second frame (<NUM>) in the first direction;
a second roller (<NUM>) provided at the first frame (<NUM>);
a third frame (<NUM>) provided in a rear surface of the second frame (<NUM>);
a flexible display unit (<NUM>) rolled around the first roller and having a first end fixed to the first frame (<NUM>) and a second end coupled to the third frame (<NUM>) and placed on the rear surface; and
a drive unit (<NUM>, <NUM>) configured to guide a sliding movement of the second frame (<NUM>) with respect to the first frame (<NUM>) in the first direction to transition the roll-slide mobile terminal from a first state to a second state , and to guide a sliding movement of the second frame (<NUM>) with respect to the first frame (<NUM>) in the second direction to transition the roll-slide mobile terminal from the second state to the first state,
wherein the second frame (<NUM>) comprises:
a flat portion (<NUM>) on a rear surface of the flexible display unit; and
a bending portion (<NUM>) rolled around the second roller (<NUM>) and having a front bending portion located in the second direction of the flat portion and a rear bending portion, and
wherein the third frame (<NUM>) is configured to slide with respect to the flat portion (<NUM>) of the second frame (<NUM>) in the first direction when the flat portion (<NUM>) of the second frame (<NUM>) moves in the first direction and the rear bending portion moves in the second direction.