Abstract:
In an opening/closing cover mechanism, an opening/closing cover is provided with a slidable plate in such a manner as to freely make a reciprocating motion in one direction. The slide plate slides in the one direction in the state in which the opening/closing cover is closed, thereby locking the opening/closing cover when the slide plate is at locked position. A cam mechanism is disposed in an opposing portion defined between an opening edge of an accommodation chamber and an outer peripheral edge portion of the opening/closing cover, both of the edges being faced with each other in the state in which the opening/closing cover is closed, to function when the slide plate slides in the one direction in the state in which the opening/closing cover is closed. The cam mechanism allows a pressing force to act on the opening/closing cover along an axial direction of a hinge axis.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application is based upon and claims the benefit of priority from Japanese Patent Application No. 2011-165103, the entire contents of which are incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an opening/closing cover mechanism for opening or closing an accommodation chamber, in which objects such as a battery and a memory card are housed, in an electronic apparatus such as a digital camera. 
         [0004]    2. Description of Related Art 
         [0005]    Conventionally, in a digital camera, as shown in  FIG. 17 , an accommodation chamber  95  for a battery  97  and an accommodation chamber  96  for a memory card  98  are formed in a rectangular housing  9 , and further, an opening/closing cover  91  for opening or closing the accommodation chambers  95  and  96  is disposed in a manner openable through a slidable hinge  92 . 
         [0006]    When the opening/closing cover  91  slides in the state in which the opening/closing cover  91  is closed, an engagement hook  93  projecting from the tip end of the opening/closing cover  91  is hooked on an engagement receiving portion  94  disposed at opening edges of the accommodation chambers  95  and  96  in the housing  9 , so that the opening/closing cover  91  is locked at a closure position. Here, the opening/closing cover  91  is elastically biased by a spring (not shown) from the closure position toward an opening direction, as required. 
         [0007]    In the conventional opening/closing cover mechanism, a clearance (of, e.g., about 0.5 mm) for smoothly opening or closing the opening/closing cover  91  is formed between the opening edges of the accommodation chambers  95  and  96  formed in the housing  9  and an outer peripheral edge portion of the opening/closing cover  91  at the closure position. Further, an axial play for permitting the opening/closing cover  91  to be moved along a hinge axis within the range of the clearance is given to the hinge  92  in the opening/closing cover  91 . 
         [0008]    With the opening/closing cover mechanism, even in a situation in which a side edge of the opening/closing cover  91  is scratched by the opening edge of the housing  9  in a process in which the opening/closing cover  91  is opened from the closure position, the opening/closing cover  91  is moved in an axial direction, thereby avoiding such a situation, whereby the opening/closing cover  91  can be opened without any scratch. 
         [0009]    However, in the opening/closing cover mechanism, the large clearance of about 0.5 mm is defined around the opening/closing cover so as to smoothly open the opening/closing cover. Therefore, the opening/closing cover has a problem about backlash in a hinge axial direction in the closed state. 
       SUMMARY OF THE INVENTION 
       [0010]    An opening/closing cover mechanism according to the present invention includes: 
         [0011]    a housing  1  having an accommodation chamber  11  which accommodates an object therein; 
         [0012]    an opening/closing cover  2  pivotally supported at a base end portion thereof by a hinge axis  41  so as to openably close the accommodation chamber  11 ; 
         [0013]    a slide plate  3  disposed in the opening/closing cover  2  in such a manner as to freely make a reciprocating motion along one direction so as to freely slide, the slide plate sliding in the one direction in the state in which the opening/closing cover  2  is closed, to lock the opening/closing cover  2  at a closure position; and 
         [0014]    a cam mechanism disposed in a facing portion defined between an opening edge of the accommodation chamber  11  and an outer peripheral edge portion of the opening/closing cover  2 , both of the edges being faced with each other in the state in which the opening/closing cover  2  is closed, to function when the slide plate  3  slides in the one direction in the state in which the opening/closing cover  2  is closed, 
         [0015]    the cam mechanism being equipped with function of acting a pressing force on the opening/closing cover  2  in an axial direction of the hinge axis  41 . 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a perspective view showing an opening/closing cover in a camera in a closed state in a first embodiment according to the present invention; 
           [0017]      FIG. 2  is a perspective view showing the opening/closing cover in the camera in an open state; 
           [0018]      FIG. 3  is a bottom view showing an unlocked state of a slide plate, the opening/closing cover being not shown; 
           [0019]      FIG. 4  is an enlarged bottom view showing a part A of  FIG. 3 ; 
           [0020]      FIG. 5  is a bottom view showing a locked state of the slide plate, the opening/closing cover being not shown; 
           [0021]      FIG. 6  is an enlarged bottom view showing a part A of  FIG. 5 ; 
           [0022]      FIG. 7  is a back view showing the opening/closing cover and the slide plate in a slide operation of the slide plate; 
           [0023]      FIG. 8  is an exploded perspective view showing the opening/closing cover and the slide plate; 
           [0024]      FIG. 9  is a perspective view showing an opening/closing cover in a camera in a closed state in a second embodiment according to the present invention; 
           [0025]      FIG. 10  is a perspective view showing the opening/closing cover in the camera in an open state; 
           [0026]      FIG. 11  is a bottom view showing an unlocked state of a slide plate, the opening/closing cover being not shown; 
           [0027]      FIG. 12  is an enlarged bottom view showing a part A of  FIG. 11 ; 
           [0028]      FIG. 13  is a bottom view showing a locked state of the slide plate, the opening/closing cover being not shown; 
           [0029]      FIG. 14  is an enlarged bottom view showing a part A of  FIG. 13 ; 
           [0030]      FIG. 15  is a back view showing the opening/closing cover and the slide plate in a slide operation of the slide plate; 
           [0031]      FIG. 16  is an exploded perspective view showing the opening/closing cover and the slide plate; and 
           [0032]      FIG. 17  is a perspective view showing a conventional opening/closing cover mechanism. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0033]    Two embodiments, in which the present invention is applied to a camera, will be specifically described below with reference to the drawings. 
       First Embodiment 
       [0034]    As shown in  FIGS. 1 and 2 , a camera according to a first embodiment of the present invention is provided with a housing  1  formed into a substantially rectangular shape, and the housing  1  has an accommodation chamber  11  which accommodates a battery (not shown). 
         [0035]    The accommodation chamber  11  in the housing  1  can be opened or closed between a closure position shown in  FIG. 1  and an open position shown in  FIG. 2  by an opening/closing cover  2  that is pivotally supported at a base end portion thereof by a hinge mechanism  4 . A slide plate  3  is disposed at the rear surface of the opening/closing cover  2 , for locking the opening/closing cover  2  at the closure position. As shown in  FIG. 1 , the slide plate  3  has an operating knob  34  that can be operated outside of the housing  1 . 
         [0036]    Incidentally, the hinge mechanism  4  incorporates therein a torsion spring (not shown) for elastically biasing the opening/closing cover  2  from the closure position shown in  FIG. 1  to the open position shown in  FIG. 2 . 
         [0037]    As shown in  FIG. 8 , the opening/closing cover  2  is provided with a substantially rectangular cover body  20 , and further, the hinge mechanism  4  having a hinge axis  41  is connected to a longitudinal base end portion of the cover body  20 . The cover body  20  has an opening  22  exposing the operating knob  34  to the outside. Moreover, the cover body  20  has a pair of slits  21  and  21  bored at the tip end thereof. 
         [0038]    The slide plate  3  is provided with a substantially rectangular flat plate  30 , which has a blade piece  31  projecting from either side thereof in a width direction. The blade piece  31  has a slide-contact surface  32  arcuately curved at the tip end thereof. Moreover, the flat plate  30  has a pair of engagement pieces  33  and  33  projecting from the tip end thereof in such a manner as to correspond to the pair of slits  21  and  21  in the opening/closing cover  2 . 
         [0039]    The slide plate  3  engages with respect to the rear surface of the opening/closing cover  2  in such a manner as to freely slide in a direction perpendicular to the hinge axis  41  of the hinge mechanism  4 , and further, cannot be relatively moved in a direction parallel to the hinge axis  41 . The slide plate  3  slides from an unlocked position shown in  FIG. 7(   a ) to a locked position shown in  FIG. 7(   b ), and thus, the pair of engagement pieces  33  and  33  of the slide plate  3  penetrates the pair of slits  21  and  21 , to thus project from the front end of the opening/closing cover  2  by a distance S. 
         [0040]    As shown in  FIG. 2 , a slide-contact receiving surface  12  arcuately curved is formed at an opening edge  10  of the accommodation chamber  11  in the housing  1 , and this position cause a slide-contact receiving surface  12  to face the blade piece  31  of the slide plate  3  by closing the opening/closing cover  2 . 
         [0041]    As shown in  FIGS. 3 and 4 , the slide-contact surface  32  of the blade piece  31  and the slide-contact receiving surface  12  of the housing  1  are separated from each other when the slide plate  3  is at the unlocked position. In contrast, as shown in  FIGS. 5 and 6 , the slide-contact surface  32  of the blade piece  31  is brought into slide-contact with the slide-contact receiving surface  12  of the housing  1  in a process in which the slide plate  3  is moved from a position immediately before the lock to the locked position. Consequently, the slide-contact surface  32  of the blade piece  31  receives a cam force from the slide-contact receiving surface  12  of the housing  1 . 
         [0042]    Here, the slide-contact surface  32  of the blade piece  31  and the slide-contact receiving surface  12  of the housing  1  are inclined with respect to the slide direction of the slide plate  3 . A component of force F generated according to the inclination acts to press the opening/closing cover  2  in one direction along the hinge axis  41 . 
         [0043]    As a consequence, the opening/closing cover  2  is slightly moved along the hinge axis  41 . The side edge of the opening/closing cover  2  is held at a position in contact with the opening edge  10  of the housing  1  when the slide plate  3  is at the locked position. Additionally, the pair of engagement pieces  33  and  33  of the slide plate  3  is inserted inside of the opening edge  10  of the housing  1 , so that the opening/closing cover  2  is locked at the closure position. 
         [0044]    In this state, the opening/closing cover  2  is held at a predetermined position along the hinge axis  41 , and therefore, a backlash does not occur because the opening/closing cover  2  has no play in the direction along the hinge axis  41 . 
         [0045]    In opening the opening/closing cover  2 , the slide plate  3  slides in a reverse direction, and then, the pair of engagement pieces  33  and  33  is unlocked. The slide of the slide plate  3  separates the slide-contact surface  32  of the blade piece  31  from the slide-contact receiving surface  12  of the housing  1 . In this manner, the opening/closing cover  2  receives the elastically biasing force in the open direction from the hinge mechanism  4 , and thus, is automatically opened from the closure position shown in  FIG. 1  to the open position shown in  FIG. 2 . 
       Second Embodiment 
       [0046]    As shown in  FIGS. 9 and 10 , a camera according to a second embodiment of the present invention is provided with a substantially rectangular housing  1 , which has an accommodation chamber  11  which accommodates a battery (not shown). 
         [0047]    The accommodation chamber  11  in the housing  1  can be opened or closed between a closure position shown in  FIG. 9  and an open position shown in  FIG. 10  by an opening/closing cover  2  that is pivotally supported at a base end portion thereof by a hinge mechanism  4 . A slide plate  3  is disposed at the rear surface of the opening/closing cover  2 , for locking the opening/closing cover  2  when the slide plate  3  is at the locked position. As shown in  FIG. 9 , the slide plate  3  has an operating knob  34  that can be operated outside of the housing  1 . 
         [0048]    Incidentally, the hinge mechanism  4  incorporates therein a torsion spring (not shown) for elastically biasing the opening/closing cover  2  from the closure position shown in  FIG. 9  to the open position shown in  FIG. 10 . 
         [0049]    As shown in  FIG. 16 , the opening/closing cover  2  is provided with a substantially rectangular cover body  20 , and further, the hinge mechanism  4  having a hinge axis  41  is connected to a longitudinal base end portion of the cover body  20 . The cover body  20  has an opening  22  exposing the operating knob  34  to the outside. Moreover, the cover body  20  has a pair of slits  21  and  21  bored at the tip end thereof. 
         [0050]    The slide plate  3  is provided with a substantially rectangular flat plate  30 , which has two blade pieces  31   a  and  31   b  projecting from both sides thereof in a width direction. The blade pieces  31   a  and  31   b  have slide-contact surfaces  32   a  and  32   b  arcuately curved, respectively, at the tip ends thereof. Moreover, the flat plate  30  has a pair of engagement pieces  33  and  33  projecting from the tip end thereof in such a manner as to correspond to the pair of slits  21  and  21  in the opening/closing cover  2 . 
         [0051]    The slide plate  3  engages with respect to the rear surface of the opening/closing cover  2  in such a manner as to freely slide in a direction perpendicular to the hinge axis  41  of the hinge mechanism  4 , and further, cannot be relatively moved in a direction parallel to the hinge axis  41 . The slide plate  3  slides from an unlocked position shown in  FIG. 15(   a ) to a locked position shown in  FIG. 15(   b ), and thus, the pair of engagement pieces  33  and  33  of the slide plate  3  penetrates the pair of slits  21  and  21 , to thus project from the front end of the opening/closing cover  2  by a distance S. 
         [0052]    As shown in  FIG. 10 , two slide-contact receiving surfaces  12   a  and  12   b  arcuately curved are formed at an opening edge  10  of the accommodation chamber  11  in the housing  1 , and this position cause two slide-contact receiving surfaces  12   a  and  12   b  to face with the two blade pieces  31   a  and  31   b  of the slide plate  3  by closing the opening/closing cover  2 . 
         [0053]    As shown in  FIGS. 11 and 12 , the slide-contact surfaces  32   a  and  32   b  of the blade pieces  31   a  and  31   b  and the slide-contact receiving surfaces  12   a  and  12   b  of the housing  1  are separated from each other when the slide plate  3  is at the unlocked position. In contrast, as shown in  FIGS. 13 and 14 , the slide-contact surfaces  32   a  and  32   b  of the blade pieces  31   a  and  31   b  are brought into slide-contact with the slide-contact receiving surfaces  12   a  and  12   b  of the housing  1  in a process in which the slide plate  3  is moved from a position immediately before the lock to the locked position. Consequently, the slide-contact surfaces  32   a  and  32   b  of the blade pieces  31   a  and  31   b  receive a cam force from the slide-contact receiving surfaces  12   a  and  12   b  of the housing  1 . 
         [0054]    Here, the slide-contact surfaces  32   a  and  32   b  of the blade pieces  31   a  and  31   b  and the slide-contact receiving surfaces  12   a  and  12   b  of the housing  1  are inclined with respect to the slide direction of the slide plate  3 . Components of force Fa and Fb generated according to the inclination act to press the opening/closing cover  2  along the hinge axis  41  in two directions face to each other. 
         [0055]    As a consequence, the opening/closing cover  2  is slightly moved along the hinge axis  41 . Both of the side edges of the opening/closing cover  2  are held at positions separate from the opening edge  10  of the housing  1  when the slide plate  3  is at the unlocked position. Additionally, the pair of engagement pieces  33  and  33  of the slide plate  3  is inserted inside of the opening edge  10  of the housing  1 , so that the opening/closing cover  2  is locked at the closure position. 
         [0056]    In this state, the opening/closing cover  2  is held at a predetermined position along the hinge axis  41 , and therefore, a backlash does not occur because the opening/closing cover  2  has no play in the direction along the hinge axis  41 . 
         [0057]    In opening the opening/closing cover  2 , the slide plate  3  slides in a reverse direction, and then, the pair of engagement pieces  33  and  33  is unlocked. The slide of the slide plate  3  separates the slide-contact surfaces  32   a  and  32   b  of the blade pieces  31   a  and  31   b  from the slide-contact receiving surfaces  12   a  and  12   b  of the housing  1 . In this manner, the opening/closing cover  2  receives the resilient biasing force in the open direction from the hinge mechanism  4 , and thus, is automatically opened from the closure position shown in  FIG. 9  to the open position shown in  FIG. 10 . 
         [0058]    Here, since both of the side edges of the opening/closing cover  2  are separated from the opening edge  10  of the housing  1 , the opening/closing cover  2  is smoothly opened without any scratch on the opening edge  10  of the housing  1 . 
         [0059]    Incidentally, the configuration of each of the constituent elements according to the present invention is not limited to that in the embodiments. Therefore, various modifications can be made by experts in the technical field without departing from the spirit of the present invention defined in claims. For example, although in the first and second embodiments, the cam mechanism including the slide-contact surface  32  of the blade piece  31  and the slide-contact receiving surface  12  of the housing  1  is provided at either or both of the sides of the slide plate  3 , one or two cam mechanisms may be provided at the tip end of the slide plate  3 .