JP5156690B2 - Private branch exchange - Google Patents

Description

  The present invention relates to a private branch exchange that accommodates extension terminals.

  In general, when receiving a call, the destination terminal rings the ringtone, blinks the incoming lamp, or displays on the display unit to notify the destination subscriber of the incoming call.

  Various techniques for changing the incoming call form such as the ring tone and the incoming lamp color for each caller or callee have been proposed so that the caller or callee can be grasped before answering.

  In Patent Document 1, identification information as to whether or not to stop the ring tone after a predetermined time is registered in advance in a private branch exchange corresponding to each of a plurality of telephones. Discloses a technique for stopping a ring tone after a certain time.

  Patent Document 2 discloses a technique for setting an incoming call form for each dial-in number.

JP-A-5-122355 JP 2006-203950 A

  The change of the incoming call type as described above is performed by setting in advance on the terminal side that receives the call or on the private branch exchange side that receives the call. In other words, it is not considered to change the incoming call destination form according to an instruction from the terminal of the transmission source.

  However, for example, when the sender wants to send an urgent message to the destination, the incoming form of the destination is changed according to the instruction from the terminal of the sender, and the urgency etc. is communicated to the destination. It may be desirable to be able to do so.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a private branch exchange capable of changing a destination incoming form at an arbitrary timing when a caller is making a call.

A private branch exchange according to the present invention executes call processing based on a predetermined incoming call type for a destination extension terminal in response to a call request from a source in a private branch exchange accommodating at least one extension terminal. And a call processing unit for continuing the call process for the extension terminal of the call destination based on an incoming call form different from the incoming call form when receiving a reminder call request from the call source during execution of the call process , The call processing unit has a transfer function for transferring an incoming call to a predetermined transfer destination when a period of the call processing passes a predetermined non-response period, and performs call processing based on a prompt call request If there is no response from the destination extension terminal even after a predetermined period of time elapses from execution, and the destination extension terminal is set as a transfer process target, it is before the non-response period has elapsed. The It characterized that you perform the transfer process.

  According to the private branch exchange according to the present invention, the incoming call form can be changed by a request from the caller at an arbitrary timing during the call, so that the callee can be prompted to respond.

Moreover, the private branch exchange according to the present invention, there is no response from the predetermined time period has elapsed destination extension terminal also from the execution of the call processing based on the reminder call request, and the destination of the internal terminal is set to the target transfer process If it is, since the transfer process even before the lapse of non-response period is performed, it is possible to hasten the start of execution of the transfer processing, Ru can increase the opportunity to quickly respond to destination.

In addition, the private branch exchange according to the present invention is a private branch exchange that accommodates at least one extension terminal, and performs call processing based on a predetermined incoming call form for a destination extension terminal in response to a call request from the source. A call processing unit configured to continue the call process for the extension terminal of the call destination based on an incoming call form different from the incoming call form when the call request is received from the caller during execution of the call process In addition, when the call processing unit receives a reminder rejection request from the extension terminal of the transmission destination during the call processing based on the reminder call request, and receives a new reminder call request from the source changing the incoming form even based on the new reminder call request you characterized by not performed.

According to the private branch exchange according to the present invention, it is possible to change the incoming forms in response to a request from a source at any time during a call, Ru can prompt a response to destination.

In addition, the private branch exchange according to the present invention receives a request for rejecting a reminder from an extension terminal as a destination when a call processing based on a reminder call request is being executed. Even if it exists, since the incoming call form is not changed based on the new prompt call request, adverse effects such as discomfort to the destination user due to the prompt call processing being performed many times can be reduced .

In one aspect of the private branch exchange according to the present invention, the private branch exchange includes an incoming call form condition storage unit that stores an incoming call form condition indicating an incoming call form according to the number of times of the reminder call request, and the call processing unit When a call-in request is received from the caller during call processing, the callee is referred to based on the call-in type according to the number of call-up requests from the caller to the callee with reference to the call-in type condition The call processing for the extension terminal is continued .

According to one aspect of the private branch exchange according to the present invention, since the incoming forms depending on the number of reminder call request to the destination from the source is changed, prompting Succoth more effectively respond to destination Can do.

In one aspect of the private branch exchange according to the present invention, the call processing unit has a function of executing a call back process for an extension terminal set as a target of the call back process, and the extension terminal as the destination is In a case where the call processing is terminated without a response from the extension terminal of the call destination to the call processing based on the incoming call form in response to the prompt call request, when the call processing ends without calling the other terminal, the extension terminal of the call destination Is set as the target of the recall process .

According to one aspect of the private branch exchange according to the present invention, the extension terminal of the transmission destination is in a call process based on the incoming call form in response to the call request and the extension terminal of the transmission destination is in communication with another terminal. When the call process is completed without answering, the extension terminal of the call destination is set as the target of the call back process. Therefore, it is possible to automatically execute the call back process setting operation in addition to the reminder call request. Since the call back process is set, the call process from the callee to the caller can be automatically performed when the call with the other terminal ends .

  In one aspect of the private branch exchange according to the present invention, the call processing unit has a function of executing a call back process for an extension terminal set as a target of the call back process, and the extension terminal as the destination is When a call with another terminal is in progress and a reminder refusal request is received from the destination, the extension terminal of the destination is set as a target for call back processing.

  According to one aspect of the private branch exchange according to the present invention, even when the reminder call processing is prohibited, the call back processing is automatically set so that the call is automatically made when the call with the other terminal is finished. Thus, it is possible to perform call processing from the transmission destination to the transmission source.

  According to the present invention, since the incoming call form of the destination is changed by a request from the source at an arbitrary timing during the call, it is possible to effectively prompt the destination to respond.

It is a block diagram which shows the whole structure of the private branch exchange system which concerns on this embodiment. It is a functional block diagram inside the memory | storage device with which a private branch exchange is provided. It is a figure which shows an example of an incoming call form condition. It is an external view of an extension telephone. It is a functional block diagram of an extension telephone. It is a sequence diagram at the time of call processing between extension telephones via a private branch exchange. It is a flowchart which shows the processing flow of a private branch exchange when it receives a call request from the extension telephone of the transmission source. It is a flowchart which shows the process sequence in case a private branch exchange registers a recall process after execution of a reminder call process. It is a flowchart which shows the process sequence in case a private branch exchange performs a transfer process after a reminder call process execution.

  A mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing the overall configuration of the private branch exchange system according to the present embodiment. In FIG. 1, a private branch exchange 100 accommodates extension telephones TEL (TEL1 to TELn), and is connected between another communication terminal and the extension telephone TEL via a network 150 such as a public network, a private line network, or an IP network. Communication or relay of communication between extension telephones TEL is performed.

  In this embodiment, in response to a reminder call request from the caller during a call, the callee's incoming call form is changed at any timing during the call being made by the caller. A private branch exchange system is provided.

  The private branch exchange 100 includes a control device 110, a storage device 120, a speech path switch 130, office trunks GT1 to GTn, and extension trunks IT1 to ITn. The control device 110, the storage device 120, and the speech path switch 130 are connected via a bus 140.

  Each of the office line trunks GT1 to GTn accommodates office lines Ls1 to Lsn connected to the network 150, respectively. Each of the extension trunks IT1 to ITn accommodates the extension telephones TEL1 to TELn via the extensions Lr1 to Lrn, respectively.

  The communication path switch 130 connects the extension trunks IT1 to ITn and the office line trunks GT1 to GTn to form a communication path under the control of the control device 110, and communicates with other communication terminals via the network 150. Control external phone calls. Further, the call path switch 130 connects the extension trunks IT1 to ITn to form a call path, and controls extension calls between the extension telephones TEL1 to TELn.

  The control device 110 is configured by a CPU, a ROM, a RAM, and the like, and controls the entire private branch exchange 100 such as call connection control by executing various programs stored in the storage device 120.

  The storage device 120 is configured by a memory such as a flash memory. The storage device 120 stores various data and programs on the extension side and the outside line necessary for the operation of the private branch exchange 100, and provides the control device 110 with various data necessary for call connection control and the like according to instructions from the control device 110.

  FIG. 2 shows functional blocks inside the storage device 120. As shown in FIG. 2, the storage device 120 includes a call control unit 124 that controls the communication path switch 130 and executes an external line call or an extension call by the extension telephones TEL <b> 1 to TELn as a program 122 executed by the control apparatus 110. Remember. Further, the storage device 120 includes a station data storage unit 126 and an incoming call form condition storage unit 128. The station data storage unit 126 forms a communication path such as the accommodation positions and extension number information of the extension trunks IT1 to ITn and the office line trunks GT1 to GTn, and stores the station data as control data for realizing an outside line call and an extension call. Remember. Also, the incoming call form condition storage unit 128 stores an incoming call form condition indicating the incoming call form of the destination corresponding to the number of reminder call requests from the caller.

  FIG. 3 shows an example of incoming call form conditions. The incoming call form condition shown in FIG. 3 includes the color of the incoming call lamp (item 102I) of the destination terminal and the destination terminal according to the number of reminder call requests (item 100I) made during the calling process from the source. The type of lighting of the incoming call lamp (item 104I) and the type of incoming call tone (item 106I) of the destination terminal are registered. Note that the type of lighting in the item 104I indicates the number of blinks of the incoming lamp per minute.

  Although details will be described later, in this embodiment, the private branch exchange 100 changes the incoming call destination form based on the incoming call form condition as shown in FIG. 3 in response to a reminder call request from the caller during the outgoing call. .

  FIG. 4 is an external view of the extension telephone TEL. As shown in FIG. 4, each of the extension telephones TEL1 to TELn includes a handset 1 for making a call when the line is connected, a display 2 for displaying caller information such as a caller telephone number, a speaker 3 for ringing, an incoming call To inform the subscriber, the lamp 4 blinks or lights up in a plurality of colors (in this embodiment, seven colors of red, blue, green, yellow, light blue, purple, and white). Button 5 is provided.

  FIG. 5 shows functional blocks of the extension telephone TEL. As shown in FIG. 5, each of the extension telephones TEL1 to TELn includes a CPU 10 that controls the entire telephone, a ROM 12 that stores each processing program, ringtone data, and the like, and a RAM 14 that is used when each processing program is executed. Further, the extension telephone TEL includes a switch interface 31 serving as a communication interface with the private branch exchange 100, a handset interface 32 serving as a communication interface with the handset 1, a speaker interface 33 serving as an interface between the speaker 3 and the CPU 10, and a call button 5. A button interface 34 serving as an interface between the various buttons of the extension telephone TEL such as the CPU 10 and the CPU 10, a lamp interface 35 serving as an interface between the lamp 4 and the CPU 10, and a display interface 36 serving as an interface between the display 2 and the CPU 10. In addition, the extension telephone TEL includes an input / output interface 30 for connecting the above-described interfaces to the CPU 10.

  In each of the extension telephones TEL1 to TELn configured as described above, when the CPU 10 receives a call request from the private branch exchange 100 via the switch interface 31, the incoming call designated by the call request from the speaker 3 via the speaker interface 33. In addition to outputting a sound, the lamp 4 blinks or lights in the color and blinking type designated by the call request via the lamp interface 35. Further, the CPU 10 displays the transmission source information on the display 2 via the display interface 36.

  When the subscriber of the extension telephone TEL who heard the ring tone picks up the handset 1 and responds (off-hook), the private branch exchange 100 performs call connection control, and the communication path between the answering extension telephone TEL and the originating extension telephone TEL is established. The call is formed.

  FIG. 6 shows a sequence at the time of calling processing between the extension telephones TEL via the private branch exchange 100. In the present embodiment, the case where the source terminal is an extension telephone TEL will be described as an example. However, the source terminal is not limited to the extension telephone TEL, and is fixed to the network 150 such as a public network. A telephone, a mobile phone, an IP telephone, or the like may be used.

  In FIG. 6, the caller extension telephone TEL makes a call request to the private branch exchange 100 (S10). More specifically, when the private branch exchange 100 detects that the originating extension telephone TEL is off-hook, the private branch exchange 100 outputs a dial tone to the originating extension telephone TEL. After the dial tone is input, the source extension telephone TEL accepts the input of the desired destination telephone number (extension number) via the numeric keypad, and the input destination telephone number is sent to the private branch exchange 100. By sending, a call request is made.

  Upon receiving the call request, the private branch exchange 100 performs call processing for the extension telephone TEL that is the destination corresponding to the telephone number specified in the call request (S12). Note that the color of the incoming call lamp, the blinking type of the incoming call lamp, and the incoming call tone in the calling process are stored in the storage device 120 in advance.

  The destination extension telephone TEL receives the calling process and outputs a designated ring tone through the speaker 3 and also performs the incoming call process by blinking or lighting the lamp 4 with the designated color and blinking type. Execute (S14).

  Thereafter, in a situation where there is no response from the extension telephone TEL as the call destination, that is, while the call of the extension telephone TEL as the call destination continues, the caller TEL Then, a reminder call request is made to the private branch exchange 100 (S16). For example, when the number at the end of the destination telephone number is input via the numeric keypad during a call, the source extension telephone TEL makes a reminder call request to the private branch exchange 100.

  The private branch exchange 100 receives the prompt call request, refers to the incoming call form condition stored in the incoming call form condition storage unit 128, and determines the color of the incoming call lamp, the flashing type, and the ring tone according to the number of receptions of the prompt call request. Identify. Further, the private branch exchange 100 controls the destination extension telephone TEL so that the incoming call form of the destination extension telephone TEL is changed to the specified incoming lamp color, blinking type, and ringing tone (S18).

  The extension telephone TEL as the call destination changes the color of the incoming lamp, the blinking type, and the ring tone by the prompt call process, and continues the call process (S20).

  Here, when there is no response from the extension telephone TEL as the call destination, and the extension telephone TEL as the call originator again makes a reminder call request (S22), the private branch exchange 100 again receives an incoming call according to the number of receptions of the reminder call request. The color of the lamp, the blinking type, and the ring tone are specified, and the reminder call process is executed (S24). The extension telephone TEL as the call destination changes the color of the incoming lamp, the blinking type, and the ring tone again by the new reminder call process, and further continues the call process (S26).

  If the destination extension telephone TEL responds by going off-hook during execution of the calling process (S28), the private branch exchange 100 forms a speech path between the source extension telephone TEL and the destination extension telephone TEL. Then, the telephone call between the extension telephones is realized (S30).

  On the other hand, when the calling extension is canceled by the on-hook of the caller extension telephone TEL during the call process (S32), the private branch exchange 100 executes the call stop process for the caller extension telephone TEL (S34). Then, the calling of the extension telephone TEL as the call destination is stopped (S36).

  As described above, in the present embodiment, the private branch exchange 100 accepts a reminder call request from the extension telephone TEL as a caller at an arbitrary timing during a call, and in response to the request, the color of the incoming lamp, the blink type, the ring tone Is changed to change the incoming call form of the extension telephone TEL as the call destination. In this way, by accepting a request for changing the incoming call form of the callee from the caller at any timing during the call, the caller is urgent to the callee when, for example, the caller wants to send an urgent message to the callee. Can tell the sex quickly.

  Here, with reference to the flowchart shown in FIG. 7, the processing flow of the private branch exchange 100 when a call request is received from the extension telephone TEL as the caller will be described.

  In FIG. 7, when the private branch exchange 100 receives a call request from a caller extension telephone TEL (S100), the private branch exchange 100 executes a call process for the caller extension telephone specified by the call request (S102).

  If a further reminder call request is received from the extension telephone TEL that is the calling source (the determination result of step S104 is affirmative “Y”), the private branch exchange 100 receives the incoming call form condition stored in the incoming call form condition storage unit 128. Referring to FIG. 4, the incoming call form corresponding to the number of reminder calls from the caller extension telephone TEL is selected (S106), and the color of the incoming call lamp for the caller extension telephone TEL, the blinking type, based on the selected call incoming call, And by changing the ringtone, a reminder call process is executed (S108).

  Further, when the private branch exchange 100 detects an off-hook from the extension telephone TEL as the call destination during the call, it determines that there is a response (the determination result in step S110 is affirmative “Y”), and Call processing is executed by forming a communication path between the extension telephones TEL (S114).

  If the private branch exchange 100 detects an on-hook state after the call process (the determination result in step S116 is affirmative “Y”), the process is terminated.

  Further, when there is no response from the extension telephone TEL as the call destination during the call (the determination result in step S110 is negative “N”) and no on-hook is detected (the determination result in step S112 is negative “N”). ), Private branch exchange 100 continues the processing from step S104 onward. If on-hook is detected in step S112, private branch exchange 100 ends the process.

  As described above, in the present embodiment, the incoming call form of the callee at an arbitrary timing during the outgoing call by the caller by changing the incoming call form of the callee in response to the prompt call request from the caller during the call. To change. Therefore, according to this embodiment, for example, when the sender wants to transmit an urgent message to the destination, the incoming form of the destination is changed according to the instruction from the terminal of the sender, and the destination is It is possible to convey urgency etc.

  In the above description, as an example of changing the incoming call form, the example of changing all the colors of the incoming call lamp, the blinking type, and the ring tone has been described. However, only one of the color of the incoming call lamp, the blinking type, and the ring tone may be changed, or only two of them may be changed. For example, when the extension telephone TEL as a call destination is in a call with another terminal, a ring tone is generally not sounded. Therefore, if the extension telephone TEL to which the call is made is in a call with another terminal and receives a reminder call request, the private branch exchange 100 changes only the color of the incoming lamp and the flashing type in response to the reminder call request. It doesn't matter.

  By the way, as described above, according to the present embodiment, it is possible to change the incoming form of the destination in accordance with an instruction at an arbitrary timing during the call from the source, and inform the destination of the urgency or the like. it can. However, even if the incoming call form of the call destination is changed, there may be a case where the call cannot be answered because the callee is making another important call.

  Accordingly, when there is no response from the call destination despite the execution of the reminder call process, the private branch exchange 100 may perform registration of “call back process (camp on)”, for example.

  Here, the call-back processing means that when an incoming call is received from a caller to an extension telephone TEL that is in a call with another terminal, the caller dials a special number to camp on the private branch exchange 100, for example. By registering, it means a process of automatically connecting a line between the call destination and the caller and calling back the caller when the call of the callee is terminated. Alternatively, the private branch exchange 100 automatically calls the extension telephone TEL as the destination when the call ends (on-hook), and the call is made in response to the extension telephone TEL being off-hook in response to the call. This is a process in which the private branch exchange 100 calls back the originating extension telephone TEL by automatically connecting the original and destination lines.

  FIG. 8 is a flowchart showing a processing procedure in the case where the private branch exchange 100 registers the call back processing after executing the reminder call processing.

  In FIG. 8, after the private branch exchange 100 executes the reminder call process (S200) and detects on-hook (S202), the on-hook detected in a situation where the other party is not responding to the caller. Is determined (S204). As a result of the determination, in the case of on-hook at the time when the call with the caller ends (when the determination result in step S204 is negative “N”), the process ends.

  On the other hand, if on-hook is detected in a situation where the other party is not responding to the caller (the determination result in step S204 is affirmative “Y”), the private branch exchange 100 will The extension telephone TEL is registered in the storage device 120 as a terminal for call back processing (S206).

  As described above, when the extension telephone TEL as the destination is registered as the terminal subject to the call back processing, the private branch exchange 100 is configured such that when the extension telephone TEL as the destination finishes the call with the other terminal, A line between the extension telephone TEL of the destination and the extension telephone TEL of the transmission source is connected, and a calling process for the extension telephone TEL of the transmission source is executed.

  As described above, when there is no response from the call destination despite the execution of the reminder call processing, the private branch exchange 100 automatically registers the extension telephone TEL as the call destination processing terminal. Also good. By automatically setting the call back process in this way, the call destination can be instantly called when the call with the other terminal is completed without performing the call back setting operation in addition to the reminder call request. Call processing from the caller to the caller can be performed automatically.

  In the above description, when the reminder call process is executed, the example in which the call back process is registered regardless of the number of times has been described. However, the reference number may be set in advance, and the call back process may be registered when the number of reminder call requests from the transmission source reaches the reference number.

  In addition, when there is no response from the call destination even though the reminder call process has been executed, and the call destination has registered the transfer process, the private branch exchange 100 preliminarily executes the transfer process. The transfer process may be executed immediately before a predetermined non-response period elapses.

  The transfer process is a process in which the private branch exchange 100 switches the call destination to a transfer destination registered in advance when the call period (number of times) has passed a predetermined non-response period (number of times). Therefore, if there is no response from the call destination even though the reminder call process is executed, the transfer process is executed before the non-response period elapses, thereby increasing the opportunity for the callee to respond quickly. be able to.

  FIG. 9 is a flowchart showing a processing procedure in the case where the private branch exchange 100 executes the transfer process after executing the reminder call process.

  In FIG. 9, the private branch exchange 100, after executing the reminder call process (S300), determines whether transfer registration for the extension telephone TEL as the call destination is performed by referring to the station data or the like (S302). As a result of the determination, if the transfer registration is not made (the determination result of step S302 is negative “N”), the process is terminated.

  On the other hand, if transfer registration has been performed (the determination result in step S302 is affirmative “Y”), the private branch exchange 100 further determines whether or not there is no response from the callee even after a predetermined period of time has elapsed after executing the reminder call process. (S304), if there is no response (determination result in step S304 is negative "N"), before the non-response period for executing the transfer process elapses, the transfer destination registered in advance is sent from the sender. The incoming call is transferred (S306). If there is a response (the determination result of step S304 is affirmative “Y”), private branch exchange 100 ends the process.

  As described above, if there is no response from the callee even after a predetermined period shorter than the non-response period has elapsed after the execution of the reminder call process, and the callee has registered for transfer processing, The exchange 100 may immediately execute the transfer process before the non-response period for executing the transfer process elapses. In this way, by accelerating the start of execution of the transfer process, it is possible to increase the opportunity for the destination to respond quickly.

  Further, in the above description, an example has been described in which the private branch exchange 100 executes a reminder call process for a call destination regardless of the situation of the call destination when a call request for the caller is received. However, for example, if the call destination call process is performed many times when the destination user is talking to another party, there is a risk that the destination user may be adversely affected such as discomfort.

  Therefore, when the destination user who has received the reminder call process performs a special operation indicating a predetermined reminder rejection request such as pressing an absent button provided on the extension telephone TEL, the extension telephone TEL will A signal relating to the operation is transmitted to the private branch exchange 100. Further, in response to the detection of the signal by the private branch exchange 100, the reminder call process for the destination is prohibited. In this way, by prohibiting the reminder call process in response to a request from the call destination, it is possible to reduce adverse effects such as discomfort to the user of the call destination due to the prompt call process being performed many times.

  In addition, the private branch exchange 100 prohibits the prompt call processing when the call destination receives a special operation indicating a reminder refusal request from the call destination during a call with another terminal, and the extension telephone TEL of the call destination. May be registered as a target terminal for the above-described call back processing. Even if the call-up process is prohibited in this way, the call-back process is automatically set, so that the call process from the callee to the caller is immediately performed when the call with the other terminal ends. It can be done automatically.

  Furthermore, in the above description, an example has been described in which the incoming call form is changed with reference to the same incoming call form condition regardless of the destination or the caller. However, the incoming call form condition stored in the incoming call form condition storage unit 128 may be prepared for each source or destination and the incoming form condition may be changed for each source or destination.

  According to the present invention, since the incoming call form is changed by a request from the caller at an arbitrary timing during the call, the callee can be prompted to respond. Therefore, the present invention can be applied to a private branch exchange or the like that accommodates extension terminals.

DESCRIPTION OF SYMBOLS 1 Handset 2 Display 3 Speaker 4 Lamp 5 Call button 100 Private branch exchange 110 Controller 120 Storage device 122 Program 124 Call control unit 126 Station data storage unit 128 Incoming form condition storage unit 130 Speech path switch 140 Bus 150 Network

Claims (5)

In a private branch exchange accommodating at least one extension terminal, in response to a call request from the caller, a call process based on a predetermined incoming call form is executed for the caller extension terminal and the call process is being executed. A call processing unit for continuing a call process for the extension terminal of the destination based on an incoming form different from the incoming form ,
Further, the call processing unit has a transfer function for transferring an incoming call to a predetermined transfer destination when a period of the call processing has passed a predetermined non-response period, and a call based on a prompt call request If there is no response from the destination extension terminal even after a predetermined period of time has elapsed since the execution of the process, and the destination extension terminal is set as a transfer process target, before the non-response period elapses private branch exchange, characterized that you perform the transfer process even. In a private branch exchange accommodating at least one extension terminal, in response to a call request from the caller, a call process based on a predetermined incoming call form is executed for the caller extension terminal and the call process is being executed. A call processing unit for continuing a call process for the extension terminal of the destination based on an incoming form different from the incoming form ,
Furthermore, when the call processing unit receives a reminder rejection request from the extension terminal of the callee during execution of the call processing based on the reminder call request, the call processor receives a new reminder call request from the caller. A private branch exchange that does not change the incoming call form based on the new reminder call request . The private branch exchange according to any one of claims 1 and 2 ,
An incoming call form condition storage unit for storing an incoming call form condition indicating an incoming call form according to the number of requests for reminder calls;
When said call processing unit, receives the reminder call request from a source during the execution of the call processing for the destination, with reference to the incoming call mode condition, the number from the originating reminder call request to the destination A private branch exchange is characterized in that the call processing for the extension terminal of the call destination is continued based on an incoming call form in accordance with. The private branch exchange according to any one of claims 1 and 2 ,
The call processing unit has a function of executing a call back process for an extension terminal set as a target of the call back process;
When the destination extension terminal is in a call with another terminal and the destination extension terminal does not respond to the call processing based on the incoming call form in response to the prompt call request, and the call processing ends. The private branch exchange is characterized in that the extension terminal of the destination is set as a target for call back processing. The private branch exchange according to claim 2 ,
The call processing unit has a function of executing a call back process for an extension terminal set as a target of the call back process;
When the extension terminal of the call destination is in a call with another terminal and receives a reminder rejection request from the call destination, the extension terminal of the call destination is set as a target for call back processing. Private branch exchange.