Abstract:
The present invention provides a foldable portable communication terminal device including a main body case and a lid case openably connected. The main body case has a side portion provided with an up key and a down key. The portable communication terminal device has a secondary battery, power supplying switch, and a control circuit incorporated therein. The control circuit switches the power supply switch to on/off when the up key and the down key are held depressed at the same time for at least the predetermined period of time. This starts or stops power supply from the secondary battery to the device body to switch the power source of the device body to on/off. Accordingly, the foldable portable communication terminal device can be realized which is adapted to turn off the power source of the device body with the main body case and the lid case folded together.

Description:
FIELD OF THE INVENTION 
   The present invention relates to foldable portable communication terminal devices capable of carrying as folded such as foldable portable telephones having a main body case and a closure case connected to the main body case openably. 
   BACKGROUND OF THE INVENTION 
   Foldable portable telephones include a main body case and a lid case which are foldable into a compact form for carrying and which are opened for making or receiving a call to expose a manual key arrangement and a speech delivery portion provided on an inner surface of the main body case and to expose a display screen and a speech receiving portion provided on the inner surface of the lid case, so that the user can speak with a calling party. 
   Such foldable portable telephones are not only convenient to carry but also free of the likelihood that some keys will be inadvertently depressed when the telephone is carried as placed in a bag or the like since the manual keys are then covered with the lid case, hence security. 
   However, the conventional portable telephones have a manual key for turning on/off a power source of a device body provided on an inner surface of a main body case, so that when the user is to turn off the power source of the device body, for example, before attending a meeting in order to avoid receiving a call during the meeting, the user needs to open the lid case to manipulate the manual key, and then still needs to close the lid case, entailing the problem of cumbersomeness in open-close manipulation of the lid case. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to provide a foldable portable communication terminal device wherein a power source of a device body can be turned off with a main body case and a lid case folded together. 
   The present invention provides the foldable portable communication terminal device comprising a casing having a main body case and a lid case openably connected thereto. The casing includes a power source circuit for supplying power to a device body, an on/off circuit for turning on/off power supply from the power source circuit to the device body, and a power supply control circuit for controlling operation of the on/off circuit. The casing has one or a plurality of manual keys so arranged on a position as to be depressed with the casing closed. The power supply control circuit turns off the on/off circuit when the one or the plurality of manual keys are held depressed for at least the predetermined period of time. 
   With the foldable portable communication terminal device of the present invention, the one or the plurality of manual keys arranged on the casing are held depressed for at least the predetermined period of time to turn off the on/off circuit, stopping the power supply from the power source circuit to the device body, causing the power source of the device body to be turned off. In this step, the one or the plurality of manual keys are so arranged on positions as to be depressed with the casing closed, so that when the power source of the device body is to be turned off, the lid case needs not to be opened or closed. Accordingly, with the foldable portable communication terminal device of the invention, the power source of the device body can be turned off with the main body case and the lid case folded together. 
   Further, with the foldable portable communication terminal device of the invention, even if the one or the plurality of manual keys are depressed for shorter than the predetermined period of time, the power source of the device body is not turned off. Only when the manual keys described are held depressed for at least the predetermined period of time, the power source of the device body is turned off. Consequently, when the device, for example, is carried as placed in a bag, it is prevented that the power source of the device body is inadvertently switched off since an article in the bag depresses the one or the plurality of manual keys. 
   Stated specifically, the device has a plurality of manual keys so arranged on positions as to be depressed with the casing closed. The power supply control circuit turns off the on/off circuit when the plurality of manual keys are held depressed at the same time for at least the predetermined period of time. As described above, there is extremely low possibility that an article in the bag will touch and depress the plurality of manual keys at the same time, and the keys will be held depressed for at least the predetermined period of time. Thus the specific construction stated above can reliably prevent the power source of the device body from being switched off inadvertently. 
   Further stated specifically, the plurality of manual keys each are changed over between different functions depending on whether the casing is opened or closed. Development in information technology in recent years enables a portable communication terminal device to be equipped with increased functions. If the portable communication terminal device having various functions has one manual key for one function mounted thereon, the device body becomes greater in size. 
   According to the specific construction described, the one or the plurality of manual keys are provided with different functions, respectively, depending on whether the casing is opened or closed, so that the number of manual keys to be mounted on the device body is decreased to diminish the size of the device body. 
   Stated more specifically, the plurality of manual keys include two manual keys, and the casing has a display exposed to the outside with the casing closed. The two manual keys each perform the function of a volume up key or a volume down key for adjusting volume of incoming speech with the casing opened, while the keys each perform the function of a scroll up key or a scroll down key for scrolling the display with the casing closed. 
   With the foldable portable communication terminal device having the specific construction described, when the casing is in its opened state, the user can speak with a calling party, and the two manual keys each perform the function of a volume up key or a volume down key for adjusting volume of incoming speech. When the casing is in its closed state, the user can view the display, and the two manual keys each perform the function of a scroll up key or a scroll down key for scrolling the display. 
   As stated above, according to the foldable portable communication terminal device embodying the invention, the power source of the device body can be turned off with the main body case and the lid case closed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view showing a foldable portable telephone when in opened state according to the present invention; 
       FIGS. 2(   a ) and  2 ( b ) are perspective views showing the foldable portable telephone when in closed state; 
       FIG. 3  is a block diagram showing electrical construction of the foldable portable telephone; 
       FIG. 4  is a flow chart showing control operation of the foldable portable telephone partially. 
   

   DETAILED DESCRIPTION OF EMBODIMENTS 
   The present invention as applied to a foldable portable telephone will be described below with reference to the drawings. The foldable portable telephone of the invention includes a flat main body case  1  and a lid case  2 , as shown in  FIG. 1 ,  FIG. 2(   a ), and  FIG. 2(   b ). An upper end of the main body case  1  and a lower end of the lid case  2  are connected to each other by a hinge mechanism  6 . Open-close manipulation can be performed from an opened state of the lid case  2  as shown in  FIG. 1  to a closed state of the lid case  2  as shown in  FIGS. 2(   a ) and  2 ( b ). A foldable casing is thus constructed. 
   The main body case  1  has a rear portion provided with an extensible antenna  3 . The main body case  1  has an inner surface provided with a group of inner surface manipulating keys  11  including an offhook key  11   a,  an onhook key  11   b,  and numerical keys  11   c,  etc. The inner surface has a lower end portion provided with a speech delivery portion  4  incorporating a microphone. Arranged on the inner surface of the main body case  1  is an open-close detection switch  17  for detecting open-close state of the lid case  2 . The open-close detection switch  17  is turned on by closing the lid case  2 , and is turned off by opening the lid case  2 . 
   The portable telephone described comprises a message key  12 , an up key  13 , and a down key  14 . These keys  12 ,  13 ,  14  are so arranged on a side portion of the main body case  1  as to be exposed to the outside even when the lid case  2  is in its closed state. Accordingly, the keys can be depressed not only when the lid case  2  is in its open state, as shown in  FIG. 1 , but also when the lid case  2  is in its closed state, as shown in  FIGS. 2(   a ) and  2 ( b ). The message key  12 , the up key  13 , and the down key  14  each perform different functions depending on whether the lid case  2  is opened or closed, as will be discussed below. 
   On the other hand, the lid case  2  has an inner surface provided with a main display  21 . The inner surface has an upper end portion provided with a speech receiving portion  5  incorporating a speaker. The main display  21  shows date and time, various menus, content of a received message, a telephone number and name of the caller when an incoming call is received, or a telephone number of a calling party when the user makes a call and the like in the same manner as in the prior art. 
   The lid case  2  has a rear portion provided with an auxiliary display  22  as shown in  FIG. 2(   b ). The auxiliary display  22  shows the number of incoming calls and received messages, a telephone number of the caller when a call is received, name of a received message sender, and content of a received message, etc. 
     FIG. 3  shows the electrical construction of the foldable portable telephone described above. With the foldable portable telephone, a telephone circuit  15  is connected to the extensible antenna  3  as illustrated, and processes the signal for a call and data communication with other portable telephone or with an ordinary telephone connected to the subscriber&#39;s telephone line. 
   The operation of the telephone circuit  15  is controlled by a control circuit  16  having a microcomputer. A microphone  41  and a speaker  51  are connected to the control circuit  16 , respectively, so that the voice of outgoing speech can be inputted, and the voice of incoming speech can be outputted. 
   Connected to the circuit  16  are the main display  21 , the auxiliary display  22 , the group of inner surface manipulating keys  11 , the message key  12 , the up key  13 , and the down key  14 , respectively. A backlight  18  is also connected to the circuit  16  for illuminating a display surface of the main display  21  and the auxiliary display  22 . The open-close detection switch  17  is connected to the circuit  16 . 
   Further, the foldable portable telephone incorporates a secondary battery (not shown) serving as a power source. Connected to the control circuit  16  is a power supply switch  19  for turning on/off the supply of power from the secondary battery to the telephone circuit  15 , the microphone  41 , the speaker  51 , the main display  21 , the auxiliary display  22 , and the backlight  18 , respecitvely. The switch  19  is on/off-controlled by the control circuit  16 . When the switch  19  is turned on, the supply of the power from the secondary battery to the telephone circuit  15 , the microphone  41 , the speaker  51 , the main display  21 , the auxiliary display  22 , and the backlight  18  is started. On the other hand, when the switch  19  is turned off, the supply of the power from the secondary battery to the telephone circuit  15 , the microphone  41 , the speaker  51 , the main display  21 , the auxiliary display  22 , and the backlight  18  is stopped. The power source of the device body is thus set to an on/off state. 
   With the foldable portable telephone, when the power source of the device body is off, the up key  13  and the down key  14  are held depressed at the same time for at least the predetermined period of time with the lid case  2  closed to cause the power source to be turned on. Further, in the same manner as in the prior art, the onhook key  11   b  is held depressed for at least the predetermined period of time with the lid case  2  opened to cause the power source to be turned on. 
   The onhook key  11   a  and the numerical keys  11   c  are thereafter manipulated with the lid case  2  opened, so that the user can speak with a calling party using the speech delivery portion  4  and the speech receiving portion  5 . 
   With the lid case  2  opened, the message key  12  described performs a function stated below. The message key  12  is held depressed for at least the predetermined period of time during incoming call waiting state to set or cancel a message mode for answering with a message, for example, saying “I am not available to speak on the phone now” when there is an incoming call. The message key  12  is held depressed for at least the predetermined period of time while the user speaks with a calling party to start recording content of talking on the phone, and is thereafter held depressed again for at least the predetermined period of time to stop recording. The message key  12  is held depressed for at least the predetermined period of time upon receiving an incoming call, immediately executing answering operation of reproducing the message, for example, “I am not available to speak on the phone now.” Further, the message key  12  is depressed for shorter than the predetermined period of time to have information on the message mode including the content of the message stated above, etc. shown on the main display  21 . 
   On the other hand, when the lid case  2  is in its closed state, the message key  12  performs the function stated below. In the case where the message key  12  is held depressed for at least the predetermined period of time during incoming call waiting state, or in the case where the key  12  is held depressed for at least the predetermined period of time while the user speaks with a calling party, or in the case where the key  12  is held depressed for at least the predetermined period of time when an incoming call is received, the message key  12  performs the same function as when the lid case  2  is in its open state. In other words, the message key  12  is held depressed for at least the predetermined period of time during incoming call waiting state to set/cancel the message mode. The key  12  is held depressed for at least the predetermined period of time while the user speaks with a calling party to start/stop recording content of talking on the phone. Immediately when the key  12  is held depressed for at least the predetermined period of time upon receiving an incoming call, the answering operation of the message reproducing is executed. Further, the message key  12  is depressed for shorter than the predetermined period of time to turn on the backlight  18  and illuminate the auxiliary display  22 . 
   When the lid case  2  is in its open state, the up key  13  and the down key  14  perform functions stated below. The up key  13  or the down key  14  is depressed during incoming call waiting state or while the user speaks with a calling party, increasing or decreasing volume of received speech. When various menus or content of the received message are shown on the main display  21 , the up key  13  or the down key  14  is depressed, scrolling up or down those shown on the display. When there is an incoming call, the up key  13  or the down key  14  is depressed, increasing or decreasing the volume of ring tone. 
   On the other hand, when the lid case  2  is in its closed state, the up key  13  and the down key  14  perform functions stated below. The up key  13  or the down key  14  is depressed during incoming call waiting state, successively having various information including the number of incoming calls and the number of received messages, etc. shown on the auxiliary display  22 . The up key  13  or the down key  14  is depressed with the content of the message shown on the auxiliary display  22 , scrolling up or down those shown on the display  22 . When there is an incoming call, the up key  13  or the down key  14  is depressed, increasing or decreasing the volume of ring tone in the same manner as in the lid case  2  open state. 
   When the lid case  2  is in its closed state with the power source of the device body set to on, as described above, the up key  13  and the down key  14  are held depressed at the same time for at least the predetermined period of time, turning off the power source. In the same manner as in the prior art, when the lid case  2  is in its open state, the onhook key  11   b  is held depressed for at least the predetermined period of time, turning off the power source. 
     FIG. 4  shows the procedure of switching on/off the power source of the device body executed by the control circuit  16  described. When the user turns on the power source of the foldable portable telephone described for the first time, required initial setting like setting ports is performed. 
   As illustrated, step S 1  inquires as to whether the open-close detection switch  17  is turned on. When the lid case  2  is in its closed state, the answer for the step S 1  is affirmative, followed by step S 2  to inquire as to whether the power source is turned on. If the inquiry is answered in the affirmative, step S 3  follows to inquire as to whether the up key  13  and the down key  14  are held depressed at the same time for at least the predetermined period of time. If the inquiry is answered in the affirmative, the sequence proceeds to step S 4  to turn off the power source, and thereafter returns to step S 1 , while if the inquiry is answered in the negative, step S 4  is skipped, and the sequence returns to step S 1 . 
   If the answer for step S 2  is negative, step S 5  follows to inquire as to whether the up key  13  and the down key  14  are depressed at the same time for at least the predetermined period of time. If the inquiry is answered in the affirmative, the sequence proceeds to step S 6  to turn on the power source, and thereafter returns to step S 1 , whereas if the inquiry is answered in the negative, step S 6  is skipped and the sequence returns to step S 1 . 
   When the lid case  2  is in its open state, the answer for step S 1  is negative, followed by step S 7  to inquire as to whether the power source is turned off. If the inquiry is answered in the negative, step S 8  follows to inquire as to whether the onhook key  11   b  is held depressed for at least the predetermined period of time. If the answer is negative, the sequence returns to step S 1 , while if the answer is affirmative, the sequence proceeds to step S 4  to turn off the power source, and thereafter returns to step S 1 . 
   If the answer is affirmative in step S 7 , step S 9  follows to inquire as to whether the onhook key  11   b  is held depressed for at least the predetermined period of time. When the inquiry is answered in the negative, the sequence returns to step S 1 . When the inquiry is, on the other hand, answered in the affirmative, step S 6  follows to turn on the power source, and the sequence returns to step S 1 . 
   With the foldable portable telephone of the invention, the up key  13  and the down key  14  provided on a side portion of the main body case  1  are held depressed at the same time for at least the predetermined period of time with the main body case  1  and the lid case  2  folded together, which can switch on/off the power source of the device body, as described above. Accordingly, when the power source of the device body is switched on/off, the user needs not to open or close the lid case  2 , hence a simple procedure in switching on/off. 
   With the foldable portable telephone described, when the up key  13  and the down key  14  are held depressed at the same time for at least the predetermined period of time, the power source is switched on/off. In the case where the telephone is carried as placed in a bag, for example, there is extremely low possibility that the up key  13  and the down key  14  are touched and depressed by an article in the bag at the same time, and the keys  13 ,  14  are held depressed for at least the predetermined period of time. Therefore, it is unlikely that the power source is switched on/off inadvertently. 
   Furthermore, the message key  12 , the up key  13 , and the down key  14  each perform different functions depending on whether the lid case  2  is opened or closed. Consequently, the number of the manual keys is smaller than the case wherein one manual key is formed for one function, whereby the device body is made compact. 
   The embodiment described above is intended to illustrate the present invention and should not be construed as limiting the invention set forth in the appended claims or reducing the scope thereof. Furthermore, the device of the invention is not limited to the embodiment in construction but can of course be modified variously without departing from the scope of the invention as set forth in the claims. 
   For example, according to the embodiment described, when the up key  13  and the down key  14  are held depressed at the same time for at least the predetermined period of time, the power source is switched on/off. The invention is, however, not limited to the above, and it is possible to use the construction wherein the power source is switched on/off when one of the message key  12 , the up key  13 , and the down key  14  is held depressed for at least the predetermined period of time, or when all the keys  12 ,  13 ,  14  are held depressed at the same time for at least the predetermined period of time.