Abstract:
An external cover of a user device includes: an upper cover; a lower cover; and a hinge connecting the upper and lower covers for pivoting the upper cover and lower cover over a front surface and a rear surface of the user device, wherein the upper cover opens and closes a front surface of the user device and comprises at least two or more folding lines along a longitudinal direction of the upper cover such that the upper cover is divided into at least three supports when folded along each of the at least two or more folding lines, and wherein the lower cover holds the user device on an inside surface, and slip preventing units are provided on at least two end surfaces of an outside surface of the second cover for providing enhanced friction between the second cover and a flat location so that the lower cover maintains a stable state in various holding mode of the lower cover facing the hinge, respectively, so that the lower cover maintains a holding state in various holding modes.

Description:
CLAIM OF PRIORITY 
     This application claims the priority under 35 U.S.C. §119(a) to Korean Application Serial No. 10-2013-0042673, which was filed in the Korean Intellectual Property Office on Apr. 18, 2013, the entire content of which is hereby incorporated by reference in its entirety. 
     BACKGROUND 
     1. Field of the Invention 
     The present disclosure relates to a user device including a smart phone and a tablet PC or other similar devices or other similar devices, and more particularly, to an external cover which can hold a portable user device while protecting an exterior of the user device. 
     2. Description of the Related Art 
     In general, users mount an external cover to a portable user device to protect the user device. The external cover is detachably provided to the user device, and protects a front surface and/or a rear surface of the user device. Since the user device is frequently carried, impacts such as a falls or other contact with objects while being carried may occur, and damage to an outer surface such as a scratches or dents may occurs on an outer surface thereof. Thus, the user device to minimize wear, damage and long term product reliability and appearance needs to be protected by the external cover. 
     In addition, the above-described external cover is recognized as an accessory which has various colors and textures to show a sense of fashion and appealing appearance to display its own personality, and provides a luxurious feeling by using an outer skin of various materials, for example, a leather material having various colors. 
     Especially, since a display of a user device such as a smart phone or a tablet PC is located on a front surface of the user device, the front surface of the user device is protected by the external cover. A generally distributed external cover includes an upper cover and a lower cover, and the upper and lower covers are connected to each other by hinges. The upper cover is rotated to be folded to and unfolded from the front surface of the user device, that is, a display screen of the user device and then may be folded over the back or rear side of the device. However, when the user device is used, it is inconvenient to type on the user device or view a displayed screen. For example, when the user device is typed on, it is convenient to type on the user device in a slightly or shallow angle inclined state, and when the displayed screen is viewed, it is convenient to view the screen in a heavily or more steeply inclined state. In order to solve the inconvenience, a separate portable holder is provided, or a holder is provided in the user device. 
     However, it may be inconvenient for the user to always carry the holder, and the user device in which the holder is provided may be awkward or cumbersome to carry and may-not have an appealing appearance. 
     Thus, the external cover of the user device is configured to perform a holding function, or a separate component is attached to the external cover so that the external cover can be used as a holder of the user device. 
     Covers for user devices having a holding function according to the related art are disclosed in detail in Korean Utility Model Application No. 2012-0007825 and Korean Patent Application No. 2012-0140504. 
     However, the cover of the user device according to the related art is folded for a holding function in various holding modes to support the user device in an inclined state, but includes a separate component, for example, a magnet or a sensor to maintain a folded state. If a magnet is provided in the external cover, for example, a steel plate should be provided. However, since a weight of the steel plate is heavy, it can make it more difficult to carry the external cover. 
     Especially, if the magnet or the steel plate is provided in the external cover to maintain various holding modes, a performance of the user device deteriorates as the magnet can effect various internal components of the user device such as, for example the display. In order to prevent this, a magnetic shielding component should be additionally used, which causes a rise in manufacturing costs and also possibly the weight of the external cover. 
     SUMMARY 
     The present invention provides an external cover of a user device which excludes the use of a magnetic body/a steel plate to achieve light weight. 
     The present invention also provides an external cover of a user device which excludes the use of a magnetic material/a steel plate to prevent deterioration of a performance of the user device and minimize a rise in price and rise in weight. The present invention also provides an external cover of a user device which is conveniently used in a holding mode for viewing the user device, or a typing mode while excluding the use of a magnetic material/a steel plate. 
     The present invention also provides the external cover of the user device which prevents a slip in a holding mode for viewing the user device, or a typing mode to provide a stable holding mode while excluding the use of a magnetic material/a steel plate. 
     In order to solve the above-described problems, there is provided an external cover of a user device, including: an upper cover; a lower cover; and a hinge connecting the upper and lower covers for pivoting the upper cover and lower cover over a front surface and a rear surface of the user device, wherein the upper cover opens and closes a front surface of the user device and comprises at least two or more folding lines along a longitudinal direction of the upper cover such that the upper cover is divided into at least three supports when folded along each of the at least two or more folding lines, and wherein the lower cover holds the user device, and slip preventing units are provided on at least two end surfaces of an outside surface of the second cover for providing enhanced friction between the second cover and a flat location so that the lower cover maintains a stable state in various holding mode of the lower cover facing the hinge, respectively, so that the lower cover maintains a holding state in various holding modes. 
     In accordance with another aspect of the present invention, there is provide an external cover of the user device, including: a first cover; a second cover; and a hinge for connecting the first and second covers for pivoting the upper cover and lower cover over a front surface and a rear surface of the user device, wherein the first cover holds the user device, and slip preventing units are provided on at least the first and second end surfaces of an outside surface of the second cover for providing enhanced friction between the second cover and a flat location so that the lower cover maintains a stable state in various holding mode so that the external cover inclinedly supports the user device in various holding modes, respectively. 
     In accordance with another aspect of the present invention, there is provided an external cover of the user device, including; a first cover; a second cover; and hinges connecting the first and second covers for pivoting the upper cover and lower cover over a front surface and a rear surface of the user device, wherein the first cover opens and closes a front surface of the user device, and comprises the first, second, and third folding lines along a longitudinal direction of the upper cover such that the first cover is divided into first, second, third, and fourth supports when folded along each of the at least two or more folding lines, wherein in a first user holding mode, the second support contacts the floor, the fourth support contacts a portion of the lower cover, the first support supports a portion between the lower cover and the second support horizontally, and the third support vertically supports a portion between the second support and the fourth support, and wherein in a second user holding mode, the first support contacts a portion of the lower cover, the third and fourth support horizontally contacts the floor, and the second support vertically supports a portion between the first support and the third support, and supports the held user device. 
     Other aspects, advantages and salient features of the external cover for user device in accordance with the present invention will become apparent to a person of ordinary skill in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view showing a state in which a user device is held by an external cover according to an embodiment of the present invention, and showing a user holding mode for viewing the user device. 
         FIG. 2  is a perspective view showing a state in which the user device is held by the external cover according to the embodiment of the present invention, and showing a user holding mode for typing on the user device. 
         FIG. 3  is a view showing the external cover of a closed state according to the embodiment of the present invention. 
         FIG. 4  is a view showing the external cover in a fully opened state according to the embodiment of the present invention. 
         FIG. 5  is a plan view showing an upper cover of the external cover according to the embodiment of the present invention. 
         FIG. 6  is a view showing a slip preventing unit mounted to an end of a lower cover of the external cover according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of the present invention will be described herein below with reference to the accompanying drawings to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. In the following description, well-known functions or constructions are not described in detail since they would obscure the understanding of the subject matter of the present invention in unnecessary detail by a person of ordinary skill in the art with unnecessary detail of the well-known functions and structures. 
     Therefore, the terms used herein should be understood based on the descriptions made herein in view of the ordinary level of skill in the art. The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. 
     The following description made with reference to the accompanying drawings is provided to help general understanding of the embodiments of the present invention which is defined by the claims and their equivalents. Although various specific details are included to help understanding of the present invention, they are regarded only as exemplary. Thus, those skilled in the art can variously change and modify the embodiments described herein without departing from the scope of the present invention. Further, a description of known functions and configurations will be omitted for clarity so as to not obscure the invention. 
     A singular form such as ‘a’, ‘an’, and ‘the’ will be construed to include a plurality of referents unless it is defined differently in the context. Thus, for example, ‘a component surface’ includes one or more surfaces. 
     The term ‘substantially’ means that cited characteristics, parameters, or values may not be accurately achieved, and allowable errors, measurement errors, accuracy limits in measurement, deviations, changes, or characteristics may be generated in a degree by which the effects of the present invention are not excluded. 
       FIG. 1  is a perspective view showing a state in which a user device  10  is held by an external cover  20  according to an embodiment of the present invention, and showing a user holding mode for viewing the display screen at a favorable angle for observing media, text and or other viewable display content on the user device.  FIG. 2  is a perspective view showing a state in which the user device  10  is held by the external cover  20  according to the embodiment of the present invention, and showing a user holding mode for facilitating typing on the user device such as in a word processing application or other similar data entry application. As shown in  FIGS. 1 and 2 , the external cover  20  according to the embodiment of the present invention is a cover by which the user device  10  may be held to be carried or otherwise observed in use. Especially, the external cover  20  refers to an external cover which protects an appearance of the held user device and has various colors and high quality materials as an accessory, and refers to an external cover which does not use a separate fixing/maintaining component. In addition, the user device  10  refers to a portable user device of general electronic products, and especially to a miniaturized/light-weighted mobile communication device. 
     The user device  10  may be applied to any one of a mobile phone, a palm-sized PC, a personal communication system (PCS), a personal digital assistant (PDA), a handheld PC (HPC), a smart phone, a wireless local area network (LAN) terminal, a laptop computer, a netbook, a notebook, and a tablet PC. The user device may be a tablet PC or a smart phone in the present embodiment, and the user device is assumed to be a tablet PC, and hereinafter a configuration of the external cover according to the embodiment of the present invention will be described below. 
     A display  100  by which a touch input can be made on a front surface of the user device  10  is disposed on the front surface of the user device  10 , and the display  100  is protected by the external cover  20 . A touch input unit  100  is disposed on the front surface of the user device  10 , and the touch input unit  100  receives and processes a contact, a motion, and a gesture of a finger or a stylus pen. The external cover  20  according to the present embodiment may include a first cover  21  in which the user device  10  is held, a second cover  22  which inclinedly supports the user device  10  while protecting the front surface of the user device  10 , a hinge h rotatably connecting the first and second covers  21  and  22 , and a slip preventing unit  23  (see  FIGS. 3 and 6 ) supporting the user device inclinedly supported in a holding mode. 
     Since the first cover  21  is disposed on a bottom surface of the user device  10 , the first cover  21  will be referred to as a lower cover, and since the second cover  22  is disposed on a top surface to open and close the user device, the second cover  22  will be referred to as an upper cover. The upper cover  22  is rotatably connected to the lower cover  21  by the hinge h to be folded to or unfolded from the top surface (a display unit) of the user device  10 , and serves to perform a holding function together with the lower cover  21  on which the user device  10  is held. In other words, the upper cover can be folded over the top of the display to protect the display, or folded over the bottom surface if the device  10  to provide a surface having a profile that is more easily grasped for holding and carrying. 
     The lower cover  21  is held while facing the user device  10 , and is intentionally held or separated by a stopper  210  provided along a periphery thereof. The stopper  210  is made of a resilient synthetic resin so that the user device  10  can be selectively attached and detached. The resin may include urethane. 
     As shown in  FIGS. 3 to 5 , the upper cover  22  may have at least two folding lines parallel to a hinge axis, and may be divided into at least three supports by the folding lines. The upper cover  22  includes first, second, and third folding lines f 1 , f 2 , and f 3 , and includes first, second, third, and fourth supports  220 ,  222 ,  224 , and  226 . The first folding line f 1  is closest to the hinge h, and the third folding line f 3  is farthest from the hinge h in other words closer to an outer edge  22  of the upper cover. The second folding line f 2  is located between the first and third folding lines f 1  and f 3 . Further, the first support  220  is closest to the hinge h, and the fourth support  226  is farthest from the hinge h. The second and third supports  222  and  224  are sequentially located between the first and fourth supports  220  and  226 . 
     The first, second, third, and fourth supports  220 ,  222 ,  224 , and  226  have substantially rectangle shapes. The second support  222  is widest, and the third and fourth supports  224  and  226  are relatively narrow or small. The first support  220  has an area whose size is between those of areas of the second support  222  and the third support  224 . The first, second, and third folding lines f 1 , f 2 , and f 3  are responsible for a hinge function. Especially, the first, second, and third folding lines f 1 , f 2 , and f 3  provided in the upper cover  22  have recess shapes, respectively, and are formed to be thinner than the other parts so that the upper cover  22  can be rotated along the folding lines. 
     As shown in  FIGS. 1 and 2 , the user device  10  can be held by the lower cover  21  or by the upper cover  22  in various user holding modes.  FIG. 1  shows a holding mode in which the held user device  10  is inclinedly supported at an angle between 60 degrees and 90 degrees, and  FIG. 2  shows a typing mode in which the held user device  10  is inclinedly supported at an angle of 30 degrees or less. The screen can be conveniently viewed when a displayed screen faces a front side of the user in the holding mode, and the typing mode can be conveniently used when the displayed screen is inclinedly held on a floor or a desk in front of a user for example. The holding function in the typing mode or the holding mode can be realized by folding the first, second, and third folding lines f 1 , f 2 , and f 3  provided in the upper cover  22  at different angles and by using the first, second, third and fourth supports  220 ,  222 ,  224 , and  226 . 
     The holding structures of the upper cover  22  in the typing mode and the holding mode will be described below. 
     In the holding mode shown in  FIG. 1 , the first support  220  of the upper cover  22  contacts a portion of a lower surface of the lower cover  21 , and the third and fourth supports  224  and  226  contact the floor or other support structure such as a desk. The second support  222  supports a portion between the first support  220  and the third support  224 . In a more detailed description of an operation of the upper cover  22 , the first support  220  is responsible for a function of supporting the user device  10  as a support when the first folding line f 1  is folded, more particularly, providing the vertical support. The second support  222  is responsible for a function of determining a holding angle when the second folding line f 2  is folded. The third and fourth supports  224  and  226  are responsible for a function of supporting the user device  10  when the second folding line f 2  is folded so that the third and fourth supports  224  and  226  contact the floor and thus provide stability along a horizontal or nearly horizontal plane. The third folding line does not need to be folded. 
     In the typing mode shown in  FIG. 2 , the second support  222  of the upper cover  22  contacts the floor, and the fourth support  226  contacts a portion of the lower cover  21  to provide a second vertical support in addition to support  220  which maintains the user device in the shallow inclined angle. The first support  220  supports a portion between the lower cover  21  and the second support  222 , and the third support  224  supports a portion between the second and fourth supports  222  and  226 . In a detailed description of an operation of the upper cover  22 , the first support  220  is folded along the first folding line f 1 , and determines a typing angle as a first support column. When an angle of the first support column is a right angle or an obtuse angle, a typing structure does not collapse even if the user device  10  is held by the lower cover  21 . If the second support  222  closely contacts the floor, a base surface having a trapezoidal shape is formed when the upper cover  22  of the typing mode is shown in a lateral direction so that the first and third supports  220  and  224  support a weight of the user device  10 . Further, the third support  224  is stood on the floor at a right angle or an obtuse angle as a second support column, and supports the user device  10 . The fourth support  226  is folded along the third folding line f 3 , and is disposed to closely contact a lower surface of the lower cover  21  so that the fourth support  226  supports the user device  10 . 
     A configuration of a slip preventing unit  23  provided in the lower cover  21  will be described below with reference to  FIGS. 3 and 6 . It has been already described that the external cover is configured to be optimized in the typing mode and the holding mode for inclinedly holding the user device  10  with the upper and lower cover  21  and  22 . The slip preventing unit  23  is responsible for a function of preventing a slip in both the two modes. If the user device  10  is held by the lower cover  21 , in either of the two modes ( FIG. 1  or  2 ), the lower cover end  230  contacts the floor (a flat location such as a desk or the ground) to support the user device  10 . The slip preventing unit  23  is located at the lower cover end  230 . A region of the lower cover end  230  includes three end surfaces of first, second, and third end surfaces  213 ,  215 , and  217 , and the first end surface  213  mainly contacts the ground in the holding mode, and the second end surface  215  mainly contacts the ground in the typing mode. Thus, the slip preventing unit  23  extends to first and second portions  232  and  234  covering the first and second end surfaces  213  and  215  to prevent a slip in the two modes, respectively. At least one slip preventing unit  23  may be provided in a longitudinal direction (hinge direction) of the lower cover end  230 . 
     The slip preventing unit  23  may be formed of rubber or silicon whose friction force is excellent, and outer surfaces of the slip preventing units may protrude from the end surfaces  213  and  215  by a predetermined thickness. 
     The scope of the present invention is not limited to the exemplified example, but those skilled in the art can variously modify the embodiment without departing from the scope of the present invention. 
     Although the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. Therefore, the scope of the present invention should not be limited to the above-described embodiments but should be determined by not only the appended claims but also the equivalents thereof.