Abstract:
There is provided an opening and closing device including a base; a movable member that is moved between a retracted position and a forward position by making linear movement and rotational movement with respect to the base; and a locking system for locking the movable member at the retracted position, wherein locking of the movable member by the locking system is released by rotationally moving the movable member, and thereby the linear movement of the movable member is allowed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application is a continuation application filed under 35 U.S.C. 111(a) claiming benefit under 35 U.S.C. 120 and 365(c) of PCT International Application No. PCT/JP2014/072417 filed on Aug. 27, 2014 and designating the U.S, the entire contents of which are hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an opening and closing device, and an electronic device. 
         [0004]    2. Description of the Related Art 
         [0005]    Digital cameras, camcorders and mobile phones are known in the art as electronic devices that are configured such that a liquid crystal display or the like is embedded into a device main body to confirm captured images. Further, an electronic device is provided that is configured such that an opening and closing device for opening and closing a display unit is provided in a device main body, and the display unit can be opened and closed with respect to the device main body, so that a liquid crystal display can be viewed from various angles. 
         [0006]    Recently, taking a self portrait photograph by using an electronic device (so called “selfie”), such as a digital camera, is becoming popular. In such a case, in a state in which the display unit is accommodated in the rear surface of the device main body, a photographer who is located in front of the device main body may not view the liquid crystal display. 
         [0007]    For this reason, an opening and closing device and an electronic device are provided that are configured such that, even if a photographer is located in front of the device main body, the display unit can be moved to a position at which the liquid crystal display can be viewed (Patent Document 1). 
       Patent Document 1: Japanese Unexamined Patent Publication No. 2006-138959 
       [0008]    The display unit that includes the liquid crystal display has, however, a relatively large thickness. Thus, with a configuration in which the display unit is pivoted around a rotational shaft with respect to the device main body, a corner portion of the display unit that is disposed at aside that is closer to the rotational shaft and a corner portion of the device main body that is disposed at a side that is closer to the rotational shaft come into contact with each other with the rotation. 
         [0009]    One of illustrative objects of an embodiment of the present invention is to provide an opening and closing device and an electronic device that can be downsized and with which operability can be enhanced. 
       SUMMARY OF THE INVENTION 
       [0010]    According to an aspect of the present invention, there are provided a base; a movable member that is moved between a retracted position and a forward position by making linear movement and rotational movement with respect to the base; and a locking system for locking the movable member at the retracted position, wherein locking of the movable member by the locking system is released by rotationally moving the movable member, and thereby the linear movement of the movable member is allowed. 
         [0011]    According to the aspect of the present invention, downsizing and enhancement of the operability can be achieved. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is an exploded perspective view of an opening and closing device according to an embodiment of the present invention; 
           [0013]      FIG. 2A  is a perspective view of the opening and closing device according to the embodiment of the present invention that is in a closed state; 
           [0014]      FIG. 2B  is a perspective view of an electronic device according to the embodiment of the present invention that is in a closed state; 
           [0015]      FIG. 3A  is a perspective view of the opening and closing device according to the embodiment of the present invention that is in an opened state; 
           [0016]      FIG. 3B  is a perspective view of the electronic device according to the embodiment of the present invention that is in an opened state; 
           [0017]      FIG. 4A  is a side view (version 1) illustrating operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0018]      FIG. 4B  is a side view (version 2) illustrating the operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0019]      FIG. 4C  is a side view (version 3) illustrating the operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0020]      FIG. 4D  is a side view (version 4) illustrating the operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0021]      FIG. 4E  is a side view (version 5) illustrating the operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0022]      FIG. 4F  is a side view (version 6) illustrating the operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0023]      FIG. 4G  is a side view (version 7) illustrating the operations of the opening and closing device and the electronic device according to the embodiment of the present invention; 
           [0024]      FIG. 5  is a diagram enlarging and showing a moving/locking system; and 
           [0025]      FIG. 6  is a perspective view of the opening and closing device according to a modified example. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    Next, a non-limiting exemplary embodiment of the present invention is explained by referring to the accompanying drawings. 
         [0027]    Note that, in all the accompanying drawings, the same or corresponding reference numerals are attached to the same or corresponding members or components, and thereby duplicate explanations are omitted. Further, the drawings are not intended to show relative ratios between members or components, except as indicated otherwise. Accordingly, specific dimensions can be determined by a person ordinarily skilled in the art in light of the following non-limiting embodiment. 
         [0028]    Further, the embodiment explained below is an example, and does not limit the invention. All the features that are described in the embodiment and their combinations may not be essential to the present invention. 
         [0029]      FIGS. 1 to 3  are diagrams illustrating an opening and closing device  10  according to the embodiment and an electronic device  1  that uses the opening and closing device  10 .  FIG. 1  is an exploded perspective view of the opening and closing device  10 .  FIG. 2A  is a perspective view showing the opening and closing device  10  in a closed state, and  FIG. 2B  is a perspective view of the electronic device  1  that is provided with the opening and closing device  10  in the closed state. Further,  FIG. 3A  is a perspective view showing the opening and closing device  10  in an opened state, and  FIG. 3B  is a perspective view showing the electronic device  1  in the opened state. Note that definitions of the opened state and the closed state are described below. 
         [0030]    The opening and closing device  10  according to the embodiment is provided in the electronic device  1 , such as shown in  FIGS. 2B and 3B , and the opening and closing device  10  is for moving a display unit  3 , so that the display unit  3  can be opened and closed with respect to a device main body  2 . 
         [0031]    Note that, in the embodiment, a digital camera is exemplified and explained as the electronic device  1 . However, application of the present invention is not limited to the digital camera, and the present invention can be broadly applied to various types of electronic devices, such as a camcorder, a cellular phone, and so forth. 
         [0032]    First, the electronic device  1  is explained. 
         [0033]    The electronic device  1  may include, for example, the device main body  2 ; the display unit  3 ; and the opening and closing device  10  that is for opening and closing the display unit  3  with respect to the device main body  2 . 
         [0034]    A display unit accommodating portion  4  is provided at a rear surface side of the device main body  2 . As shown in  FIG. 2B , in the closed state, the display unit  3  can be accommodated in the display unit accommodating portion  4 . 
         [0035]    Further, an image capturing lens (not shown) for taking a photograph is provided at a front surface side of the device main body  2 . Additionally, inside the device main body  2 , various types of electronic components are disposed that are for executing an image capturing process. 
         [0036]    A display device, such as a liquid crystal display  5 , is integrally embedded in the display unit  3 . An image that is captured by the image capturing lens can be displayed on the liquid crystal display  5  that is provided in the display unit  3 . Thus, a photographer can confirm, by the liquid crystal display  5 , a screen that is to be captured. 
         [0037]    During taking of a general photograph, the display unit  3  is accommodated in the display unit accommodating portion  4  of the device main body  2 , as shown in  FIG. 2B . Note that, in the following explanation, a state of the electronic device  1  and a state of the opening and closing device  10  in which the display unit  3  is accommodated in the display unit accommodating unit  4  are referred to as closed states. 
         [0038]    Recently, taking a self portrait photograph by an electronic device (so called “selfie”), is becoming popular, and the electronic device  1  has a configuration corresponding to this. Specifically, the display unit  3  is configured such that it can be rotated with respect to the device main body  2  in the directions that are indicated by arrows A 1  and A 2  in  FIG. 2B  by the opening and closing device  10 . 
         [0039]      FIGS. 3B and 4F  indicate a state in which the display unit  3  is opened with respect to the device main body  2 . In this state, both the image capturing lens and the liquid crystal display  5  that are provided in the device main body  2  are positioned at the front surface side. Namely, the position of the liquid crystal display  5  at the opened state is inverted with respect to the position of the liquid crystal display  5  in the closed state. 
         [0040]    Consequently, a photographer can take a photograph while confirming himself/herself by the liquid crystal display  5  (i.e., a so-called “selfie” can be taken). Note that, in the following explanation, an opened state is said to be a state in which the display unit  3  is opened to a position at which a self portrait photograph can be taken. 
         [0041]    Next, the opening and closing device  10  is explained. 
         [0042]    As shown in  FIG. 1 , the opening and closing device  10  may include bases  11 L and  11 R; an arm plate  20 ; moving/locking systems  25 L and  25 R; a rotation plate  30 ; springs  40 L and  40 R; hinge systems  50 L and  50 R, and so forth. 
         [0043]    Note that, in each of the figures that is used for the explanation, for elements that are symmetrically arranged in the left and right directions (the X 1  and X 2  directions in the figure), an element that is located at a right side (the side in the X 1  direction) is indicated by attaching a symbol “R,” and an element that is located at a left side (the side in the X 2  direction) is indicated by attaching a symbol “L.” 
         [0044]    The bases  11 L and  11 R are formed of metal plates by press forming. The bases  11 L and  11 R have configurations such that fastening portions  12 L and  12 R and upright portions  13 L and  13 R are integrally formed, respectively. The fastening portions  12 L and  12 R are fastened to the device main body  2 . 
         [0045]    Note that, in the embodiment, a configuration is shown such that the bases  11 L and  11 R are separated from the device main body  2 . However, the bases  11 L and  11 R can be integrated with the device main body  2 . For a case of such a configuration, the bases  11 L and  11 R may be formed together with the device main body  2  by a resin. 
         [0046]    The upright portion  13 L is provided with a pin fixing hole  14 L and a pin fixing hole  15 L, and the upright portion  13 R is provided with a pin fixing hole  14 R and a pin fixing hole  15 R. First slide pins  60 L and  60 R are fixed to the pin fixing holes  14 L and  14 R, respectively. Second slide pins  61 L and  61 R are fixed to the pin fixing holes  15 L and  15 R, respectively. 
         [0047]    At this time, the first slide pins  60 L and the second slide pins  61 L are fixed so that they protrude toward inside from the base  11 L, and the first slide pins  60 R and the second slide pins  61 R are fixed so that they protrude toward inside from the base  11 R. Further, the first slide pin  60 L and the second slide pin  61 L are disposed so that they are separated in a longitudinal direction of an arm portion  23 L, and the first slide pin  60 R and the second slide pin  61 R are disposed so that they are separated in a longitudinal direction of an arm portion  23 R. 
         [0048]    An arm plate  20  is configured such that it can be moved linearly and rotationally with respect to the bases  11 L and  11 R. Namely, the arm plate  20  is configured such that it can be moved linearly in the longitudinal direction of the bases  11 L and  11 R (the direction of the arrows Y 1  and Y 2  in the figure), and at the same time, the arm plate  20  is configured such that it can be moved rotationally around the second slide pins  61 L and  61 R (in the following explanation, the linear movement may be referred to as a slide). 
         [0049]    The arm plate  20  is formed of a metal plate by press forming, and the arm plate  20  is integrally formed with a main portion  21 , the arm portions  23 L and  23 R, and so forth. 
         [0050]    The base main portion  21  has a substantially rectangular shape. The arm portions  23 L and  23 R are formed at respective end portions of the main portion  21  (both end portions in the directions of the arrows X 1  and X 2  in the figure). The arm portions  23 L and  23 R are bent at a right angle with respect to the base main portion  21 . Thus, the arm portions  23 L and  23 R protrude with respect to the base main portion  21 . 
         [0051]    The arm portion  23 L may include a pin fixing hole  22 L; a shaft hole  24 L; an L-shaped hole  26 L; a long hole  28 L; a fixing hole  29 L, and so forth. The arm portion  23 R may include a pin fixing hole  22 R; a shaft hole  24 R; an L-shaped hole  26 R; a long hole  29 R; a fixing hole  29 L, and so forth. 
         [0052]    The pin fixing holes  22 L and  22 R are formed at respective ends of the arm portions  23 L and  23 R (the end portions in the direction of the arrow Y 2 ). A spring pin  36 L is fixed to the pin fixing hole  22 L, and one end portion of a spring  40 L is connected to the spring pin  36 L. A spring pin  36 R is fixed to the pin fixing hole  22 R, and one end portion of a spring  40 R is connected to the spring pin  36 R. 
         [0053]    The shaft holes  24 L and  24 R are formed at the other end portions (the end portions in the direction of the arrow Y 1  in the figure) of the arm portions  23 L and  23 R, respectively. The rotation plate  30  is attached to the shaft holes  24 L and  24 R through the hinge systems  50 L and  50 R, respectively. 
         [0054]    The L-shaped hole  26 L and the long hole  28 L are formed so that they are arranged between the pin fixing hole  22 L and the shaft hole  24 L. The L-shaped hole  26 R and the long hole  28 R are formed so that they are arranged between the pin fixing hole  22 R and the shaft hole  24 R. The L-shaped hole  26 L and the long hole  28 L are formed to be elongated in the longitudinal direction of the arm portion  23 L. The L-shaped hole  26 R and the long hole  28 R are formed to be elongated in the longitudinal direction of the arm portion  23 R. 
         [0055]    The L-shaped hole  26 L may include a long hole portion  26 - 1 L and a locking portion  26 - 2 L. The L-shaped hole  26 R may include a long hole portion  26 - 1 R and a locking portion  26 - 2 R. The long hole portion  26 - 1 L is formed to be extended in the longitudinal direction of the arm portion  23 L (the direction of the arrows Y 1  and Y 2  in the figure). The long hole portion  26 - 1 R is formed to be extended in the longitudinal direction of the arm portion  23 R (the direction of the arrows Y 1  and Y 2  in the figure). Further, the locking portion  26 - 2 L is formed at an end portion of the long hole portion  26 - 1 L (the end portion at the side of the direction of the arrow Y 1  in the figure) such that the locking portion  26 - 2 L extends in a direction (the direction of the arrow Z 1  in the figure) that is substantially perpendicular to the longitudinal direction of the arm portion  23 L. The locking portion  26 - 2 R is formed at an end portion of the long hole portion  26 - 1 R (the end portion at the side of the direction of the arrow Y 1  in the figure) such that the locking portion  26 - 2 R extends in a direction (the direction of the arrow Z 1  in the figure) that is substantially perpendicular to the longitudinal direction of the arm portion  23 R. Note that specific shapes of the locking portions  26 - 2 L and  26 - 2 R are described below. 
         [0056]    The fixing holes  29 L and  29 R are holes for attaching slide guides  35 L and  35 R to the arm portions  23 L and  23 R, respectively. Bosses  39 L and  39 R (the boss  39 R is not shown in the figure) are formed in the slide guides  35 L and  35 R, respectively. The slide guides  35 L and  35 R can be attached to the arm portions  23 L and  23 R by fitting the bosses  39 L and  39 R into the fixing holes  29 L and  29 R, respectively. 
         [0057]    The slide guide  35 L is disposed between the base  11 L and the arm portion  23 L. The slide guide  35 R is disposed between the base  11 R and the arm portion  23 R. The slide guides  35 L and  35 R can be formed of a material having a favorable slippage, such as a fluorine-based resin. 
         [0058]    Further, in the slide guide  35 L, an L-shaped hole  37 L and a long hole  38 L are formed that have shapes corresponding to the L-shaped hole  26 L and the long hole  28 L that are formed in the arm portion  23 L. In the slide guide  35 R, an L-shaped hole  37 R and a long hole  38 R are formed that have shapes corresponding to the L-shaped hole  26 R and the long hole  28 R that are formed in the arm portion  23 R. 
         [0059]    The arm plate  20  that is configured as described above is attached to the bases  11 L and  11 R. In a state in which the arm plate  20  is attached to the bases  11 L and  11 R, the slide guide  35 L is disposed between the base  11 L and the arm portion  23 L, and the slide guide  35 R is disposed between the base  11 R and the arm portion  23 R. Thus, the arm plate  20  can be smoothly slid with respect to the bases  11 L and  11 R. 
         [0060]    Further, in the state in which the arm plate  20  is attached to the bases  11 L and  11 R, the first slide pin  60 L passes through the L-shaped hole  37 L and the L-shaped hole  26 L, and the first slide pin  60 R passes through the L-shaped hole  37 R and the L-shaped hole  26 R. Thus, the first slide pins  60 L and  60 R protrude toward inside the arm portions  23 L and  23 R, respectively. 
         [0061]    Furthermore, in the state in which the arm plate  20  is attached to the bases  11 L and  11 R, the second slide pin  61 L passes through the long hole  38 L and the long hole  28 L, and the second slide pin  61 R passes through the long hole  38 R and the long hole  28 R. 
         [0062]    The first slide pin  60 L can be relatively moved within the L-shape hole  26 L and the L-shape hole  37 L, and the first slide pin  60 R can be relatively moved within the L-shape hole  26 R and the L-shape hole  37 R. Similarly, the second slide pin  61 L can be relatively moved within the long hole  38 L and the long hole  28 L, and the second slide pin  61 R can be relatively moved within the long hole  38 R and the long hole  28 R. 
         [0063]    As described above, the one end portion of the spring  40 L is connected to the spring pin  36 L that is fixed to the arm portion  23 L, and the one end portion of the spring  40 R is connected to the spring pin  36 R that is fixed to the arm portion  23 R. Further, the other end portion of the spring  40 L is connected to the first slide pin  60 L that protrudes toward inside the arm portion  23 L, and the other end portion of the spring  40 R is connected to the first slide pin  60 R that protrudes toward inside the arm portion  23 R. 
         [0064]    Namely, the springs  40 L and  40 R are disposed between the bases  11 L and  11 R and the arm plate  20 . The springs  40 L and  40 R are for elastically biasing the arm plate  20  with respect to the bases  11 L and  11 R, so that the arm plate  20  can be moved toward a proceeding position. 
         [0065]    In the embodiment, coil springs are used as the springs  40 L and  40 R, and their disposed positions are close to the arm portions  23 L and  23 R, respectively. As described below, the rotation plate  30  is disposed between the pair of the arm portions  23 L and  23 R. However, the coil springs do not interfere with the rotation plate  30  because the coil springs are small. 
         [0066]    Note that, in the embodiment, the coil springs are used for elastically biasing the arm plate  20 . However, another elastic member (e.g., a torsion spring) may be used. 
         [0067]    Next, the rotation plate  30  is explained. 
         [0068]    The rotation plate  30  is formed of a metal plate by press forming. The rotation plate  30  may include a main portion  31 ; bent portions  32 ; attachment arms  33 L and  33 R, and so forth. The display unit  3  of the electronic device  1  is attached to the rotation plate  30 . Thus, the display unit  3  can move together with the rotation plate  30 . 
         [0069]    The slide main portion  31  has a substantially rectangular shape, and its outer peripheral four edges are bent at almost the right angle, and thereby the bent portions  32  are formed. The liquid crystal display  5  that is provided in the display unit  3  is attached to inside the bent portions  32 . 
         [0070]    The attachment arms  33 L and  33 R are integrally formed in the main portion  31  at both end portions of the rotation plate  30  in the direction of the arrow Y 1  in the figure. The attachment arm  33 L is rotatably connected to, by using the hinge system  50 L, the shaft hole  24 L that is provided in the arm  23 L, and the attachment arm  33 R is rotatably connected to, by using the hinge system  50 R, the shaft hole  24 R that is provided in the arm  23 R. 
         [0071]    The hinge systems  50 L and  50 R are for connecting the rotation plate  30  to the arm plate  20 , so that the rotation plate  30  can be rotated in the directions of the arrows A 1  and A 2  in the figure. The hinge system  50 L may include a hinge pin  51 L; a spacer  52 L; a click plate  53 L, and so forth. The hinge system  50 R may include a hinge pin  51 R; a spacer  52 R; a click plate  53 R, and so forth. 
         [0072]    Next, the moving/locking systems  25 L and  25 R are explained. 
         [0073]    The moving/locking systems  25 L and  25 R can function as a moving system for sliding (linearly moving) and rotationally moving the arm plate  20  with respect to the bases  11 L and  11 R. Additionally, the moving/locking systems  25 L and  25 R can function as a locking system for locking the arm plate  20  at a closed position. 
         [0074]    The moving/locking system  25 L may include the L-shaped hole  26 L; the long hole  28 L; the first slide pin  60 L; the second slide pin  61 L; the spring  40 L, and so forth. The moving/locking system  25 R may include the L-shaped hole  26 R; the long hole  28 R; the first slide pin  60 R; the second slide pin  61 R; the spring  40 R, and so forth. 
         [0075]    As described above, the first slide pin  60 L is configured such that it can be moved relatively and within the L-shaped hole  26 L and the L-shaped hole  37 L, and the first slide pin  60 R is configured such that it can be moved relatively and within the L-shaped hole  26 R and the L-shaped hole  37 R. Further, the second slide pin  61 L is configured such that it can be moved relatively and within the long hole  28 L and the long hole  38 L, and the second slide pin  61 R is configured such that it can be moved relatively and within the long hole  28 R and the long hole  38 R. 
         [0076]    Thus, in a state in which the arm plate  20  is attached to the bases  11 L and  11 R, the arm plate  20  can be slid with respect to the bases  11 L and  11 R in the longitudinal direction of the arm portions  23 L and  23 R by moving the first slide pins  60 L and  60 R with respect to the long hole portions  26 - 1 L and  26 - 1 R of the L-shaped holes  26 L and  26 R while the first slide pins  60 L and  60 R are guided by the long hole portions  26 - 1 L and  26 - 1 R of the L-shaped holes  26 L and  26 R, respectively, and by moving the second slide pins  61 L and  61 R with respect to the long holes  28 L and  28 R (the long holes  38 L and  38 R) while the second slide pins  61 L and  61 R are guided by the long holes  28 L and  28 R (the long holes  38 L and  38 R), respectively. 
         [0077]      FIG. 5  is a diagram enlarging and showing the moving/locking systems  25 L and  25 R. As shown in  FIG. 5 , the first slide pins  60 L and  60 R are inserted into the L-shaped holes  26 L and  26 R, respectively, and the second slide pins  61 L and  61 R are inserted into the long holes  28 L and  28 R, respectively. 
         [0078]    While the display unit  3  of the electronic device  1  is in the closed state, the first slide pins  60 L and  60 R are positioned within the locking portions  26 - 2 L and  26 - 2 R of the L-shaped holes  26 L and  26 R, respectively, and the slide pins  60 L and  60 R are locked by the locking portions  26 - 2 L and  26 - 2 R, respectively. Thus, even if the arm plate  20  is biased by the springs  40 L and  40 R, and thereby the arm plate  20  is to be slid with respect to the bases  11 L and  11 R, the slide can be restricted by the locking of the first slide pins  60 L and  60 R by the locking portions  26 - 2 L and  26 - 2 R. 
         [0079]    Note that, in the following explanation, the state in which the first slide pins  60 L and  60 R of the moving/locking systems  25 L and  25 R are locked by the locking portions  26 - 2 L and  26 - 2 R, respectively, is referred to as a locked state. Additionally, the position of the arm plate  20  in the locked state is referred to as a retracted position. 
         [0080]    The locking portions  26 - 2 L and  26 - 2 R are formed in a direction that is substantially perpendicular to the longitudinal direction of the arm portions  23 L and  23 R. Thus, the first slide pins  60 L and  60 R can be relatively moved within ranges (the ranges that are indicated by the arrow W in  FIG. 5 ) in which the locking portions  26 - 2 L and  26 - 2 R are formed. 
         [0081]    As the first slide pins  60 L and  60 R move within the locking portions  26 - 2 L and  26 - 2 R, respectively, the arm plate  20  is rotated with respect to the bases  11 L and  11 R while using the second slide pins  61 L and  61 R as an axis of rotation. The locking portions  26 - 2 L and  26 - 2 R have arc shapes that correspond to the trajectories of the first slide pins  60 L and  60 R. 
         [0082]    As the first slide pins  60 L and  60 R relatively move within the locking portions  26 - 2 L and  26 - 2 R in the direction that is indicated by the arrow B 2  in  FIG. 5 , respectively, and the first slide pins  60 L and  60 R reach the long hole portions  26 - 1 L and  26 - 1 R, respectively, the locking of the first slide pins  60 L and  60 R by the locking portions  26 - 2 L and  26 - 2 R is released. Consequently, the first slide pins  60 L and  60 R are in a state in which the first slide pins  60 L and  60 R can be slid within the long hole portions  26 - 1 L and  26 - 1 R, respectively. 
         [0083]    Consequently, the arm plate  20  is in a state in which the arm plate  20  can be slid (can be linearly moved) with respect to the bases  11 L and  11 R, and the arm plate  20  slides while being biased by the springs  40 L and  40 R. At this time, the rotation plate  30  also slides in the direction of the arrow Y 1  in the figure together with the arm plate  20  because the rotation plate  30  is attached to the arm plate  20  through the hinge systems  50 L and  50 R. 
         [0084]    The slide of the arm plate  20  is stopped as the first slide pins  60 L and  60 R contact the end portions of the L-shaped holes  26 L and  26 R in the direction of the arrow Y 2  in the figure, respectively, and the second slide pins  61 L and  61 R contact the end portions of the long holes  28 L and  28 R in the direction of the arrow Y 2  in the figure, respectively. Hereinafter, the position of the arm plate  20  in the stopped state is referred to as a forward position. 
         [0085]    While the arm plate  20  is slid, the second slide pins  61 L and  61 R, which can be a center of the rotation of the arm plate  20  with respect to the bases  11 L and  11 R, move along the long holes  28 L and  28 R, respectively. In this manner, in the embodiment, the second slide pins  61 L and  61 R, which can be the center of the rotation of the arm plate  20 , can be moved and rotated with respect to the long holes  28 L and  28 R, and can be slid (linearly moved) with respect to the long holes  28 L and  28 R, respectively. 
         [0086]    The rotation plate  30  is configured such that it can be rotated regardless of the position of the arm plate  20 . During the closed state of the electronic device  1  and the opening and closing device  10 , as the rotation plate  30  is rotated in the direction that is indicated by the arrow A 2  in the figure, the rotation plate  30  is superposed on the arm plate  20  (cf.  FIG. 2A ). Hereinafter, the position where the rotation plate  30  is superposed on the arm plate  20  is referred to as a closed position. 
         [0087]    In contrast, as the rotation plate  30  is rotated in the direction that is indicated by the arrow A 1  in the figure, a state of the electronic device  1  and the opening and closing device  10  becomes the opened state. In the opened state, the rotation plate  30  is inverted with respect to the closed position, and the rotation plate  30  is substantially parallel with the bases  11 L and  11 R. Hereinafter, the position of the rotation plate  30  at which the rotation plate  30  is parallel with the bases  11 L and  11 R is referred to as an opened position. 
         [0088]    Next, the operation of the electronic device  1  and the opening and closing device  10  having the above-described configuration is explained by referring to  FIGS. 4A-4G . 
         [0089]    Note that, in  FIGS. 4A-4G , the operation of the electronic device  1  and the opening and closing device  10  on the left side is shown. The explanation and depiction of the right side are omitted because the operation of the electronic device  1  and the opening and closing device  10  on the right side is the same as that of the left side. 
         [0090]    Note that, in  FIGS. 4A-4G , for convenience of the explanation, the shapes of the electronic device  1  and the opening and closing device  10  are depicted to be partially different from the shapes that are shown in  FIGS. 1-3 . However, the shapes are substantially the same. 
         [0091]      FIGS. 2A ,  2 B, and  4 A show the electronic device  1  and the opening and closing device  10  in the closed state. In the closed state, the arm plate  20  is positioned at the retracted position by sliding in the direction of the arrow Y 2  in the figure, and the rotation plate  30  is positioned at the closed position by rotating in the direction of the arrow A 2 . 
         [0092]    Further, in the closed state, the first slide pins  60 L and  60 R of the moving/locking systems  25 L and  25 R are locked at the locking portions  26 - 2 L and  26 - 2 R, respectively. Thus, regardless of the biasing force of the springs  40 L and  40 R, the retracted position of the arm plate  20  is maintained. 
         [0093]    In order to cause the above-described closed state of the electronic device  1  and the opening and closing device  10  to be transitioned to the opened state, the display unit  3  can be rotated in the direction of the arrow A 1  in the figure.  FIG. 4B  shows a state in which the display unit  3  is rotated in the direction of the arrow A 1  in the figure by a slight amount. 
         [0094]    By rotating the display unit  3 , the rotation plate  30  to which the display unit  3  is attached is rotated, with respect to the arm plate  20 , around the hinge systems  50 L and  50 R. 
         [0095]    Now, as shown in the figures by the arrows, the end portion of the device main body  2  and the end portion of the display unit  3  at the side at which the hinge systems  50 L and  50 R are provided are denoted by P 1  and P 2 , respectively. By rotating the display unit  3 , the corner portion P 1  of the device main body  2  contacts the corner portion P 2  of the display unit  3 . The contact position is denoted by the arrow D in  FIGS. 4B-4E . 
         [0096]    By further rotating the display unit  3  in the direction of the arrow A 1 , the leverage effect is generated at the display  3  with the contact position D as a supporting point. Consequently, force is applied to the arm plate  20  that is for rotating the arm plate  20  around the second slide pins  61 L and  61 R. Specifically, the force is applied to the arm plate  20  that is for rotating the arm plate  20  in the direction that is indicated by the arrow B 1  in  FIG. 4B . 
         [0097]    As the arm plate  20  rotates in the direction of the arrow B 1  in the figure, the first slide pins  60 L and  60 R relatively move in the direction of the arrow B 2  in the figure within the locking portions  26 - 2 L and  26 - 2 R, respectively, as shown in  FIGS. 4C and 4D . 
         [0098]    As described above, the shapes of the locking portion  26 - 2 L and  26 - 2 R correspond to the rotation trajectories of the first slide pins  60 L and  60 R (i.e., the arc shapes). Thus, when the first slide pins  60 L and  60 R are to be moved within the locking portions  26 - 2 L and  26 - 2 R, the first slide pins  60 L and  60 R tend to be displaced in the direction of the arrow Y 1  in the figure. 
         [0099]    In the embodiment, as shown in  FIG. 5 , the clearance that is indicated by the arrow ΔL 1  in  FIG. 5  is provided between the second slide pin  61 L and the long hole  28 L, and between the second slide pin  61 R and the long hole  28 R. The length of the clearance ΔL 1  corresponds to an amount of the above-described relative displacement of the first slide pins  60 L and  60 R in the direction of the arrow Y 1 . Thus, as the device main body  2  is moved in the direction of the arrow A 1  in the figure, the first slide pins  60 L and  60 R can be smoothly moved within the locking portions  26 - 2 L and  26 - 2 R, respectively. 
         [0100]      FIG. 4E  shows a state that is immediately prior to separation of the first pins  60 L and  60 R from the locking pins  26 - 2 L and  26 - 2 R, respectively. As the display unit  3  is further moved in the direction of the arrow A 1  in the figure from this state, the first slide pins  60 L and  60 R are separated from the locking portions  26 - 2 L and  26 - 2 R, respectively, and the first slide pins  60 L and  60 R proceed to the long hole portions  26 - 1 L and  26 - 1 R of the L-shaped holes  26 L and  26 R, respectively. 
         [0101]    Consequently, the locking of the arm plate  20  by the moving/locking systems  25 L and  25 R is released, and the arm plate  20  is in a slidable state. Thus, the arm plate  20  can be slid (linearly moved) toward the forward position, as the arm plate  20  is biased by the springs  40 L and  40 R, as the first slide pin  60 L and  60 R relatively move within the long hole portions  26 - 1 L and  26 - 1 R of the L-shaped holes  26 L and  26 R, respectively, and as the second slide pins  61 L and  61 R relatively move within the long holes  28 L and  28 R, respectively. 
         [0102]    Further, in a state in which the arm plate  20  is moved to the forward position, by rotating the rotation plate  30  to the opened state, the liquid crystal display  5  that is provided in the display unit  3  can be rotated to the opened position where the liquid crystal display  5  is directed to the front side (in the figure, the side of the direction of Z 2  is the front side). 
         [0103]      FIG. 4F  shows a state in which the rotation plate  30  is moved to the opened position. In this state, the device main body  2  and the display unit  3  are vertically arranged in parallel. In this manner, by rotating the rotation plate  30  to the opened position, the state of the electronic device  1  and the opening and closing device  10  becomes the opened state, thereby allowing so called “selfie” to be taken. 
         [0104]    The operation for rotating the display unit  3  from the opened position toward the closed position is substantially reverse to the above-described operation for moving the display unit  3  from the closed position toward the opened position. 
         [0105]    In order to cause the state of the electronic device  1  and the opening and closing device  10  to be transitioned to the closed state, the display unit  3  (the rotation plate  3 ) can be moved in the direction of the arrow A 2  in the figure. By doing this, the end portion (which is indicated by the arrow P 3  in the figure) of the device main body  2  contacts the display unit accommodating portion  4  of the device main body  2 , as shown in  FIG. 4G . At this time, the forward position of the arm plate  20  is maintained. 
         [0106]    In this state, the display unit  3  is tilted with respect to the device main body  2  (the state of the display unit  3  is referred to as a tilted state, hereinafter). Even if the state is the tilted state, the electronic device  1  according to the embodiment can take a photograph. For example, during so-called “high-angle photographing” such that the electronic device  1  is disposed above an eye line of a photographer, and photographing is performed in a downward direction, photographing angles can be diversified. That is because the photographer can directly view the liquid crystal display  5  from below, for example. 
         [0107]    In order to cause the state of the electronic device  1  and the opening and closing device  10  to be transitioned to the closed state, the display unit  3  can be further moved from the tilted state toward the closed state. 
         [0108]    By moving the display unit  3  toward the closed position, the first slide pins  60 L and  60 R and the second slide pins  61 L and  61 R are moved from the positions that are shown in  FIG. 5  by the dashed line to the positions that are shown by the solid line (moved toward the direction of the arrow Y 1  in the figure). Then, after the slide pins  60 L and  60 R are moved to the positions facing the locking portions  26 - 2 L and  26 - 2 R, respectively, the display unit  3  can be pressed toward the device main body  2 . 
         [0109]    By doing this, the first slide pins  60 L and  60 R are locked to the locking portions  26 - 2 L and  26 - 2 R, respectively, and the arm plate  20  is again in the state in which the arm plate  20  is locked at the retracted position by the moving/locking systems  25 L and  25 R. 
         [0110]    As described above, in the electronic device  1  and the opening and closing device  10  according to the embodiment, the arm plate  20  can be slid with respect to the bases  11 L and  11 R. Thus, slimming and downsizing can be achieved. 
         [0111]    Additionally, locking and unlocking of the display unit  3  (the arm plate  20 ) with respect to the device main body  2  (the bases  11 L and  11 R) can be performed by one action, namely, by only rotating the display unit  3 . Thus, operability can be enhanced. 
         [0112]      FIG. 6  shows an opening and closing device  80  according to a modified example of the embodiment. 
         [0113]    In the above-described embodiment, the first slide pins  60 L and  60 R and the second slide pins  61 L and  61 R are provided in the bases  11 L and  11 R, respectively, and the L-shaped holes  26 L and  26 R and the long holes  28 L and  28 R are provided in the arm plate  20 . 
         [0114]    However, as shown in  FIG. 6 , the first slide pins  60 L and  60 R and the second slide pins  61 L and  61 R can be provided in the arm plate  20 , and the L-shaped holes  26 L and  26 R and the long holes  28 L and  28 R can be provided in the bases  11 L and  11 R, respectively. 
         [0115]    The preferred embodiment of the present invention is described in detail above. However, the present invention is not limited to the above-described specific embodiment, and various modifications and alterations can be made within the gist of the present invention that is described in the scope of the claims.