Abstract:
In a hinge apparatus for rotatably connecting a first housing and a second housing of an electronic apparatus, the hinge apparatus includes a first rotating portion adapted to be connected to the first housing and a second rotating portion adapted to be connected to the second housing and rotatable with respect to the first rotating portion. The second rotating portion unrotatably holds a switch. A cam member is disposed to face the switch. The cam member is rotatable with respect to the second rotating portion and adapted to be engaged with the second housing in a rotating direction of the hinge apparatus. The switch includes a conductive first contact and a conductive second contact faced to the first contact and adapted to be connected to and disconnected from the first contact. The cam member has a cam portion for pressing the second contact following the rotation of the cam member to connect and disconnect the second contact to and from the first contact.

Description:
This application claims priority to prior Japanese patent application JP 2003-383053, the disclosure of which is incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   This invention relates to a hinge apparatus for use in an electronic apparatus, such as a mobile telephone, a personal digital assistant (PDA), and a notebook-type personal computer. 
   For example, a mobile telephone generally comprises an operating part and a display part. The operating part is provided with an operating portion. The display part is provided with a display surface. Recently, the operating part and the display part are often connected by a hinge apparatus to be foldable, i.e., openable and closable. Such a mobile telephone will hereunder be call a foldable mobile telephone. 
   With the foldable mobile telephone, the display part may be opened only when it is desired and required. Thus, it is possible to protect the operating portion and the display surface and to prevent an operation error. Further, the mobile telephone in a closed state is reduced in size and is therefore convenient for a user to carry. In addition, the operating portion and the display surface can easily be increased in size. 
   A mobile terminal of the type is disclosed, for example, in Japanese Patent Application Publication (JP-A) No. 2002-320014. The mobile terminal comprises a pair of housings connected to each other to be openable and closable around a rotating portion, and a switch for detecting an opened state and a closed state of the housings. The switch is disposed inside one of the housings. Thus, the opened state and the closed state of the housings are detected by the switch. It is therefore possible to design the mobile terminal so that a power supply to the mobile terminal is automatically turned on and off when the housings are opened and closed, respectively. 
   However, the switch is disposed inside the one housing so that the mobile terminal is inevitably increased in size and complicated in structure. 
   SUMMARY OF THE INVENTION 
   It is therefore an object of the present invention to provide a hinge apparatus having a switch and adapted to realize an electronic apparatus compact in size and simple in structure. 
   It is another object of the present invention to provide an electronic apparatus including the hinge apparatus of the type described. 
   Other object of the present invention will become clear as the description proceeds. 
   According to an aspect of the present invention, there is provided a hinge apparatus for connecting a first housing and a second housing of an electronic apparatus so that the first and the second housings are rotatable with respect to each other, the hinge apparatus comprising a first rotating portion adapted to be connected to the first housing, a second rotating portion adapted to be connected to the second housing and rotatable with respect to the first rotating portion, a switch unrotatably held by the second rotating portion, and a cam member disposed to face the switch, the cam member being rotatable with respect to the second rotating portion and adapted to be engaged with the second housing in a rotating direction of the hinge apparatus, the switch including a conductive first contact and a conductive second contact faced to the first contact and adapted to be connected to and disconnected from the first contact; the cam member having a cam portion for pressing the second contact following the rotation of the cam member to connect and disconnect the second contact to and from the first contact. 
   According to another aspect of the present invention, there is provided an electronic apparatus comprising a first housing, a second housing, and the hinge apparatus described in the above, the hinge apparatus connecting the first and the second housing so that the first and the second housings are rotatable with respect to each other. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view of a camera-equipped electronic apparatus having a hinge apparatus according to a first embodiment of the present invention; 
       FIG. 2  is a perspective view of the electronic apparatus in  FIG. 1  with a different camera position; 
       FIG. 3  is an exploded perspective view of the electronic apparatus in  FIGS. 1 and 2 ; 
       FIG. 4A  is a perspective view of a characteristic part, including the hinge apparatus, of the electronic apparatus in  FIGS. 1 through 3  in an exploded state; 
       FIGS. 4B and 4C  are perspective views of the characteristic part, including the hinge apparatus, of the electronic apparatus in  FIGS. 1 through 3  during assembling; 
       FIGS. 5A through 5C  are perspective views of the characteristic part, including the hinge apparatus, of the electronic apparatus in  FIGS. 1 through 3  in an assembled state; 
       FIG. 6  is a perspective view showing an internal structure of the hinge apparatus by removing some of components thereof; 
       FIG. 7  is an enlarged view of a part in  FIG. 4A ; 
       FIG. 8  is a perspective view of a switch illustrated in  FIGS. 4A and 6 ; 
       FIG. 9  is a perspective sectional view of the switch illustrated in  FIG. 8 ; 
       FIG. 10  is an exploded perspective view of the switch illustrated in  FIG. 8 ; 
       FIG. 11  is a perspective view of a foldable mobile telephone having a hinge apparatus according to a second embodiment of the present invention in a closed state; 
       FIG. 12  is a perspective view of the foldable mobile telephone in  FIG. 11  in an opened state; 
       FIG. 13  is an exploded perspective view of the foldable mobile telephone in  FIGS. 11 and 12 ; 
       FIG. 14  is a perspective view of a characteristic part, including the hinge apparatus, of the foldable mobile telephone in  FIGS. 11 through 13  in an exploded state; 
       FIG. 15  is a perspective view of the characteristic part, including the hinge apparatus, of the foldable mobile telephone in  FIGS. 11 through 13  during assembling; 
       FIG. 16  is an enlarged perspective view of a part of  FIG. 15  as seen in a different direction; 
       FIG. 17  is a side view showing an ON state where a switch illustrated in  FIG. 14  turns on; and 
       FIG. 18  is a side view showing an OFF state where the switch turns off. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   At first referring to  FIGS. 1 through 3 , description will be made of a camera-equipped electronic apparatus having a hinge apparatus according to a first embodiment of the present invention. 
   The electronic apparatus illustrated in the figure comprises a first housing  1  having large-sized case members  1   a  and  1   b , a second housing  2  having small-sized case members  2   a  and  2   b , a camera  3  held by the second housing  2 , a hinge apparatus  4  interposed between the first and the second housings  1  and  2 , and a flexible board (FPC)  5 . The hinge apparatus  4  has a cylindrical structure splittable into two sections in a radial direction and comprises first and second rotating portions  6  and  7  arranged adjacent to each other on a same axis. The first rotating portion  6  is connected to the flexible board  5 . The second rotating portion  7  is rotatable with respect to the first rotating portion  6  and is fixed to the camera  3 . 
   The first housing  1  is connected to the hinge apparatus  4  so as to encase the first rotating portion  6 . The first rotating portion  6  is engaged with the first housing  1  in a rotating direction so as to be unrotatable. The flexible board  5  is fixedly disposed inside the first housing  1  and has a part rolled and received in the first rotating portion  6 . The second housing  2  is connected to the hinge apparatus  4  so as to encase the second rotating portion  7  and encloses the camera  3  to protect the camera  3 . Thus, the first and the second housings  1  and  2  are connected to each other to be rotatable with respect to each other. 
   Referring to  FIGS. 4A to 4C  and  5 A to  5 C in addition, the hinge apparatus  4  will be described in detail. 
   The hinge apparatus  4  further has a switch  8  and a switch ring or cam member  9  for driving the switch  8 . The second rotating portion  7  has a cylindrical portion  10  formed at one end in an axial direction. The cylindrical portion  10  has a receiving portion  10   a  as a recess having a rectangular section, a cylindrical outer peripheral surface  10   b , and a cut portion  10   c  extending from the outer peripheral surface  10   b  to the receiving portion  10   a . At a part of the receiving portion  10   a , two conductor portions  5   a  are exposed as a part of a circuit formed on the flexible board  5 . With a structure which will later become clear, the switch  8  is received or inserted in the receiving portion  10   a  to be unrotatable and removable. 
   Referring to  FIGS. 7 to 10 , the switch  8  will be described. 
   The switch  8  has an insulating base  8   a  having a rectangular section equivalent to that of the receiving portion  10   a , two narrow fixed contacts (first contacts)  8   b  held by the base  8   a  and having conductivity and elasticity, and a wide movable contact (second contact)  8   c . The fixed contacts  8   b  are disposed in two grooves  8   a   1  formed on the base  8   a , respectively. Each of the fixed contacts  8   b  is formed into a generally U shape and has a first contacting portion  8   b   1  located on one side of the base  8   a  and a second contacting portion  8   b   2  located on the other side of the base  8   a . The movable contact  8   c  is formed into a generally L shape and has a movable contacting portion  8   c   1  faced to the first contacting portion  8   b   1  with a space left therebetween, and a protruding portion  8   c   2  as an operating portion. When the protruding portion  8   c   2  is pressed, the movable contacting portion  8   c   1  is brought into contact with the first contacting portions  8   b   1  of the two fixed contacts  8   b  to electrically connect the fixed contacts  8   b  through the movable contacting portion  8   c   1 . In other words, the switch  8  is turned into an ON state. When pressing force upon the protruding portion  8   c   2  is released, the movable contacting portion  8   c   1  is separated from the first contacting portions  8   b   1  under elastic restoring force of the movable contact  8   c  so that the fixed contacts  8   b  are electrically isolated or separated from each other. In other words, the switch  8  is turned into an OFF state. 
   As mentioned above, the switch  8  is received in the receiving portion  10   a  formed in the hinge apparatus  4  and having the rectangular section. Then, the switch  8  is inhibited from rotation about a center axis of the hinge apparatus  4  because the base  8   a  is engaged with a side wall of the receiving portion  10   a . In this state, the second contacting portions  8   b   2  are contacted with the conductor portions  5   a . The protruding portion  8   c   2  protrudes from the outer peripheral surface  10   b  of the cylindrical portion  10  through the cut portion  10   c . With this structure, the switch  8  is received in the hinge apparatus  4  and, therefore, the switch  8  need not be arranged at another position. Thus, the electronic apparatus can be designed to be compact in size. 
   Turning back to  FIGS. 4A through 4C  and  5 A through  5 C, the cam member  9  will be described. 
   The cam member  9  has a cylindrical shape with one end as a closed end and is fitted over the cylindrical portion  10  to be rotatable. As a result, the cam member  9  is faced to the switch  8  in the radial direction. The cam member  9  has an outer peripheral surface provided with an engaging portion  9   a  to be engaged with the first housing  1  in the rotating direction. The cam member  9  has an inner peripheral surface provided with a cylindrical surface  9   b  close to the outer peripheral surface  10   b  of the cylindrical portion  10 , and a recess or an escape portion  9   c  partially depressed from the cylindrical surface  9   b . The recess  9   c  is formed at a position faced to the cut portion  10   c  when the cam member  9  is rotated with respect to the cylindrical portion  10 . As will be described in the following, the cylindrical surface  9   b  and the recess  9   c  serve as a cam portion for operating the switch  8  following relative rotation between the second rotating portion  7  and the cam member  9 . 
   Referring to  FIGS. 1 through 10 , an operation of the hinge apparatus  4  will be described. 
   Referring to  FIG. 1 , the electronic apparatus is in a normal state where the camera  3  protrudes from the first housing  1  contained in a main body of the electronic apparatus. In the normal state, a user or photographer can normally take a photograph of a front scene. It is assumed here that, in the normal state, the protruding portion  8   c   2  of the switch  8  is faced to the cylindrical surface  9   b  of the cam member  9 . Therefore, the cylindrical surface  9   b  is engaged with the protruding portion  8   c   2  to push the protruding portion  8   c   2  inward so that the switch  8  is turned into an ON state. 
   Referring to  FIG. 2 , the electronic apparatus is in a special state where the camera  3  is rotated by 180° from the state in  FIG. 1  and retreated. In the special state, the photographer can take a photograph of himself. It is assumed here that, in the special state, the protruding portion  8   c   2  of the switch  8  is faced to the escape portion  9   c  of the cam member  9 . Therefore, pushing force upon the protruding portion  8   c   2  is released so that the switch  8  is turned into an OFF state. 
   As mentioned above, the switch  8  is turned on and off in response to rotation of the second housing  2  with respect to the first housing  1 , i.e., in response to change in position of the camera  3 . Therefore, if the switch  8  is in an ON state, it is possible to obtain a switch signal for inverting a camera image upside down as compared with that when the switch  8  is in an OFF state. 
   In the above-mentioned electronic apparatus, switching of the switch  8  responsive to the relative rotation between the first and the second housings  1  and  2  is controlled by a simple cam mechanism. Therefore, the electronic apparatus is not complicated in structure. Further, the switch signal may be used for turning on and off a power supply of the camera. 
   Next referring to  FIGS. 11 through 13 , description will be made of a foldable mobile telephone having a hinge apparatus according to a second embodiment of the present invention. 
   The foldable mobile telephone illustrated in the figures comprises an operating part  11  having a first housing including a pair of cases  12  and  13 , and a display part  14  having a second housing including a pair of cases  15  and  16 . The operating part  11  is provided with an operating portion. The display part  14  is provided with a display surface. The hinge apparatus  4  connects the operating part  11  and the display part  14  so that the operating part  11  and the display part  14  are foldable, i.e., openable and closable. The first and the second rotating portions  6  and  7  of the hinge apparatus  4  are connected to flexible boards  5 , respectively. The first rotating portion  6  is engaged with the first housing of the operating part  11  in the rotating direction. The second rotating portion  7  is engaged with the second housing of the display part  14  in the rotating direction. 
   Referring to  FIGS. 14 through 16 , the hinge apparatus  4  will be described. Parts similar to those in the first embodiment are designated by like reference numerals and will not be described any longer. 
   The switching ring or cam member  9  has two flat surfaces  9   d  formed on the outer peripheral surface thereof and faced to each other. The flat surfaces  9   d  serve to be engaged with the first housing of the operating part  11  in the rotating direction. 
   When the protruding portion  8   c   2  of the switch  8  is faced to the cylindrical surface  9   b  of the cam member  9  as illustrated in  FIG. 17 , the switch  8  is in an ON state. When the display part  14  is opened and the switch  8  is rotated as illustrated in  FIG. 18  following the rotation of the second rotating portion  7 , the protruding portion  8   c   2  of the switch  8  is faced to the escape portion  9   c  of the cam member  9 . As a result, the switch  8  is turned into an OFF state. 
   While this invention has thus far been described in conjunction with the preferred embodiments thereof, it will be readily possible for those skilled in the art to put this invention into practice in various other manners without departing from the scope of this invention. For example, the two embodiments have been described in the foregoing. However, the electronic apparatus may be modified in design in various manners. For example, the two conductor portions of the flexible board may be replaced by one conductor portion and the two first contacts may be replaced by one first contact. A closed circuit is formed by the second contact, the one conductor portion, and the one first contact.