Abstract:
A communication apparatus comprises a communicating circuit, a connecting unit for connecting a telephone or the communicating circuit to a line, a disconnecting unit for disconnecting the telephone from the line, a call reception detection circuit, a detection circuit for detecting a hook state of the telephone, an output unit for outputting a signal indicating that the call generation limitation mode has been set, a display for displaying that the apparatus is in the call generation limitation mode, and a dial signal transmission unit. A call generation of an attached telephone can be limited with a simple construction and a call generation limiting function of the data communication apparatus can be certainly realized.

Description:
This application is a continuation of application Ser. No. 08/648,864 filed May 16, 1996, now abandoned, which is a continuation of Ser. No. 08/260,217 filed Jun. 14, 1994, abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a communication apparatus having a call generation limiting function and an attached telephone. 
     2. Related Background Art 
     Among facsimile apparatuses, there is a facsimile apparatus having a call generation limiting function to limit a call generation for a facsimile transmission or the like. 
     According to the call generation limiting function, for example, a key code for a specific call generation limitation is set and the user inputs the key code from an operation panel of a facsimile apparatus, thereby setting the facsimile apparatus into a call generation limitation state. 
     The conventional call generation limiting function as mentioned above, however, limits only a call generation from the facsimile apparatus main body, so that a call can be generated from an attached telephone and a handset. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a communication apparatus which can limit a call generation of an attached telephone. 
     It is another object of the invention to limit the call generation of the attached telephone by a simple construction. 
     Further another object of the invention is to certainly realize a call generation limiting function of a data communication apparatus. 
     The above and other objects and features of the present invention will become more apparent from the following detailed description and appended claims with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic constructional diagram of the first embodiment of the invention; 
     FIG. 2 is comprised of FIGS. 2A to  2 C are flowcharts showing the operation of the first embodiment; 
     FIG. 3 is comprised of FIGS. 3A to  3 C are flowcharts showing the operation of the second embodiment of the invention; 
     FIG. 4 is a schematic constructional diagram of the third embodiment of the invention; 
     FIG. 5 is a flowchart showing the operation of the third embodiment of the invention; 
     FIG. 6 is a schematic constructional diagram of the fourth embodiment of the invention; and 
     FIG. 7 is a flowchart showing the operation of the fourth embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is a block diagram showing a construction of a facsimile apparatus in an embodiment of the invention. 
     The facsimile apparatus of the embodiment comprises: an off-hook detection circuit  2  to which a telephone  1  is connected and which detects the on-hook/off-hook of the telephone  1 ; an H relay  3  for switching the telephone  1  to a line  5  side or a power source side and for applying a voltage to the telephone  1 ; a CI detection circuit  4  for detecting a CI (call signal) from the telephone line  5  (L 1 -L 2 ); a line switching circuit (CML relay)  6  for switching the telephone line  5  to the telephone  1  or a modem  9  side; a console unit  7  for executing various kinds of key inputs; a CPU  8  for controlling a whole apparatus main body; the modem  9  for executing modulation/demodulation of transmission/reception signals; and a memory  10 . The line switching circuit includes a dialing circuit to transmit a dial pulse or a PB signal. 
     FIGS. 2A to  2 C are flowcharts showing the operation in the first embodiment. The line switching circuit  6  is set so that the line  5  is connected to the telephone  1  in an initial state. 
     When a call generation limitation is requested from the console unit  7  by the operator (S 1 ), the CPU  8  turns on a call generation limitation flag in a predetermined region in the memory  10  (S 2 ) and switches the H relay  3  from the line  5  side to the power source side (S 3 ). Since telephone  1  is not connected t 0  line  5 , an outgoing call cannot be initiated by the telephone. When the call generation limitation is released (S 4 ), the call generation limitation flag is turned off (S 5 ) and the H relay is switched from the power source side to the line side (S 6 ) and the telephone  1  can initiate an outgoing call. 
     When a CI signal is received from the line  5  and the CI signal is detected by the CI detection circuit  4  (S 7 ), a reception flag in a predetermined region in the memory  10  is turned on and a T 1  timer provided on the memory  10  is started (S 8 ). 
     When the call generation of outgoing calls is limited (S 9 ), since the H relay  3  has been set to the power source side, the CPU  8  switches the H relay  3  from the power source side to the line  5  side (S 10 ). Due to this, the CI signal from the line  5  reaches the telephone  1 , a ringer of the telephone  1  is rung, and the signal reception is informed to the operator. It is also possible to construct in a manner such that when the CI signal is detected, a buzzer of the console unit is rung and when the telephone  1  is off hooked, the H relay  3  is switched to the line  5  side. 
     After the elapse of a T 1  time since the CI signal was not detected (S 11 ), if the call generation is limited (S 17 ), the CPU  8  again switches the H relay  3  to the power source side (S 18 ) and turns off the reception flag (S 19 ). 
     When the telephone  1  is off hooked at the time of call generation limitation (S 12 ), since the H relay  3  is on the power source side at the time of call generation (S 13 ), a selection signal is not transmitted to the line  5 , so that the operator cannot perform the speech communication (S 14 ). When the operator is called, since the H relay  3  is on the line  5  side (S 13 ), the speech communication can be performed (S 15 ). 
     In the case where the telephone  1  is on hooked (S 16 ), if the call generation is limited (S 17 ), the H relay  3  is again switched to the power source side (S 18 ) and the reception flag is turned off (Sl 9 ). 
     In an automatic reception mode, when the CI signal is detected, the line switching circuit  6  is switched to the modem  9  side and the automatic reception is executed. 
     In a state in which the call generation limitation flag has been turned on, even when a call generation is instructed from the console unit  7 , it is rejected. 
     FIGS. 3A to  3 C are flowcharts showing the operation in the second embodiment. An apparatus of the second embodiment will be explained on the assumption that the apparatus has the construction shown in FIG.  1 . 
     In the initial state, the line switching circuit  6  and the H relay  3  are set so that the line  5  is connected to the telephone  1 . 
     When a call generation limitation is requested from the console unit  7  by the operator (S 21 ), the call generation limitation flag is turned on (S 22 ). When the call generation limitation is released (S 23 ), the call generation limitation flag is turned off (S 24 ). 
     When the CI signal is received from the line  5  and the CI signal is detected by the CI detection circuit  4  (S 25 ), the reception flag is turned on (S 26 ). 
     At the time of call generation limitation, when the telephone  1  is off hooked (S 27 ) and in case of no reception, the H relay  3  is switched from the line  5  side to the power source side (S 29 ). Since no selection signal is transmitted to the line, the operator cannot perform the speech communication (S 30 ). If there is a reception, since the H relay  3  is not switched to the power source side, the speech communication can be performed (S 31 ). 
     When the telephone  1  is on hooked (S 32 ) and at the time of call generation limitation (S 33 ), the H relay  3  is again switched to the power source side (S 34 ) and the reception flag is turned off (S 35 ). 
     In the automatic reception mode, when the CI signal is detected, the line switching circuit  6  is switched to the modem  9  side and the automatic reception is executed. 
     In a state in which the call generation limitation flag has been turned on, even if the call generation is instructed from the console unit  7 , it is rejected. 
     FIG. 4 shows a construction of the third embodiment of the invention. In FIG. 4, constructing elements which are common to those in FIG. 1 are designated by the same reference numerals. 
     FIG. 5 is a flowchart showing the operation of the third embodiment. 
     In a state in which an ordinary call generation limitation is not executed, a call is generated from the telephone  1  and a speech communication with another telephone can be performed through the line  5 . 
     When the call generation is limited, however, a state in which the telephone  1  has been off hooked is detected by the off-hook detection circuit  2  of the facsimile apparatus (S 501 ). When the call generation limitation is judged (S 502 ), the line switching circuit  6  is made operative and switches to the modem  9  side (S 503 ). Due to this, the telephone  1  side is disconnected from the outer line  5  and the speech communication cannot be performed. As mentioned above, the call generation can be also limited in the telephone  1 . 
     The CPU  8  of the facsimile apparatus activates the timer (S 504 ). When the timer is ended after the line was held for a predetermined time (S 505 ), the CPU  8  disconnects the line by returning the line switching circuit  6  to the former state (S 506 ). The value of the timer can be preset from the console unit  7 . 
     The fourth embodiment of the invention will now be explained. 
     FIG. 6 is a block diagram for explaining a construction of the embodiment. FIG. 7 is a flowchart showing the operation of the embodiment. 
     In a state in which an ordinary call generation limitation is not executed, a call is generated from the telephone  1  and a speech communication with another telephone can be executed through the line  5 . 
     When the call generation is limited, however, a state in which the telephone  1  has been off hooked is detected by the off-hook detection circuit  2  of the facsimile apparatus (S 601 ). When the call generation limitation is judged (S 602 ), the line switching circuit  6  is made operative and switches to the modem  9  side (S 603 ). 
     The H relay  3  is switched in order to notify that the line  5  has been switched to the modem  9  side and the call generation has been limited to the telephone  1  side by a voice generation circuit  11  (S 604 ). Due to this, the telephone  1  side is disconnected from the outer line  5  and the speech communication cannot be performed, so that the call generation can be also limited in the telephone  1 . 
     The CPU  8  of the facsimile apparatus starts the timer (S 605 ) and holds the line for a predetermined time. For this period of time, the CPU  8  allows the voice generation circuit  11  to generate a voice indicative of the execution of the call generation limitation to the telephone  1  (S 606 ). When the timer is ended (S 607 ), by returning the H relay  3  and the line switching circuit  6  to the original states, the line is disconnected (S 608 ). 
     In step S 606 , the CPU  8  notifies the telephone  1  by voice that the call generation is limited and also displays the call generation limitation on a display of the console unit  7 . 
     The CPU  8  repetitively executes the notification by the voice and the notification by the display simultaneously or sequentially. 
     The priority order of the notification by the voice and the notification by the display can be preset from the console unit  7 . 
     In the automatic reception mode, when the CI signal is detected, the line switching circuit  6  is switched to the modem  9  side and the automatic reception is executed. 
     In a state in which the call generation limitation flag has been turned on, even a call generation is instructed from the console unit  7 , it is rejected. 
     Although the present invention has been described above on the basis of the preferred embodiments, the invention is not limited to the constructions of the above embodiments. The invention can be also applied to not only an apparatus to communicate facsimile data but also an apparatus to communicate character data. Various modifications are possible within the spirit and scope of the appended claims of the invention.