Patent Publication Number: US-2007121887-A1

Title: Telephone system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2005-276076, filed Sep. 22, 2005, the entire contents of which are incorporated herein by reference.  
     BACKGROUND  
      1. Field  
      One embodiment of the invention relates to a telephone system, for instance, in which a plurality of main apparatuses are connected with each other via a private network.  
      2. Description of the Related Art  
      AS for a networking system, for instance, in an enterprise including a plurality of office branches and sales offices, main apparatuses such as key telephone sets are installed in each branch office or sales office, respectively, to connect among these main apparatuses via a communication network such as a private network. A system of this kind can perform extension communications among different main apparatuses and external line outgoing/incoming calls through the different main apparatuses as well as can perform inter-extension communications and external line outgoing/incoming calls for each main apparatus.  
      Meanwhile, in this system, an auto call distribution (ACD) service which is implemented in a system of a stand-alone main apparatus has been examined (for example, Jpn. Pat. Appln. KOKAI Publication No. 11-112666). This ACD service is configured in that a single ACD group is composed of a plurality of extension terminals or a plurality of main apparatuses, and prevents a concentration of incoming calls to a specific extension terminal to efficiently treat the incoming calls by equally distributing the incoming calls from external lines. In the ACD group, in general, a single representative telephone number is granted, and a caller can arrive at the extension terminals in the ACD group by dialing the representative telephone number.  
      In the system, to achieve the ACD service, it is needed to provide resource management databases for an incoming call distribution for each main apparatuses. Therefore, the system compresses a memory capacity by the extent to provide the databases and also has to perform setting registrations of the databases for resource management over again for each main apparatus, respectively, at every time when a system change in telephone number schedule and main apparatus expansion, etc., then, it will take a lot of time and require a great deal of labor to maintain the system. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
      A general architecture that implements the various feature of the invention will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments of the invention and not to limit the scope of the invention.  
       FIG. 1  is an exemplary schematic configuration view showing a first embodiment of a telephone system regarding the present invention;  
       FIG. 2  is an exemplary functional block diagram showing a connecting configuration between a main apparatus operating as a master unit and a main apparatus operating as a slave unit in the first embodiment shown in  FIG. 2 ;  
       FIG. 3  is an exemplary view showing an example of a storage content in a management table shown in  FIG. 2 ;  
       FIG. 4  is an exemplary view showing another example of the storage content in the management table shown in  FIG. 2 ;  
       FIG. 5  is an exemplary schematic sequence view showing transmission/reception operations of information between a master main apparatus and a slave main apparatus in performing login state update in the first embodiment of the present invention;  
       FIG. 6  is an exemplary sequence view showing transmission/reception operations of information between a master main apparatus and a slave main apparatus in performing an ACD, as a second embodiment of the present invention;  
       FIG. 7  is an exemplary sequence view showing transmission/reception operations of information between a master main apparatus and a slave main apparatus in performing an ACD and waiting a free telephone terminal, as a third embodiment of the present invention; and  
       FIG. 8  is an exemplary sequence view showing transmission/reception operations of information between a master main apparatus and a slave main apparatus in performing an ACD and in performing an incoming call transfer between a master main apparatus and a main apparatus to be a transfer destination without any free telephone terminal, as a forth embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION  
      Various embodiments according to the invention will be described hereinafter with reference to the accompanying drawings, In general, according to one embodiment of the invention, a telephone system, comprising at least a single of a first main apparatus which houses a plurality of telephone terminals and a second main apparatus which is connected to the first main apparatus via a communication network to house a plurality of telephone terminals therein, wherein the first main apparatus comprises: a memory which stores a management table in which a plurality telephone terminals housed in the first and the second main apparatuses, respectively, and sate information showing each operation state of the plurality of telephone terminals are associated with each another; and a controller which updates the state information in the management table based on the state information transmitted from the second main apparatus, refers to the management table when an incoming call arrives, and executes incoming call control to the plurality of the telephone terminals based on the reference result, and the second main apparatus comprises: a transmitter which monitors each operation state of the plurality of the telephone terminals, and when the operation states are changed, transmits state information of the telephone terminals of which the operation states have changed to the first main apparatus.  
     First Embodiment  
       FIG. 1  is the schematic configuration view showing the first embodiment of the telephone system regarding the present invention.  
      The system includes a private network  1 . A plurality of main apparatuses BT 1 -BTn (n is natural number) are connected to the private network. Telephone terminals T 11 -T 1   i  (i is natural number), T 21 -T 2   m  (m is natural number), T 31 -T 3   p  (p is natural number), and Tn 1 -Tnk (k is natural number) are connected to the main apparatuses BT 1 -BTn. The main apparatuses BT 1 -BTn are connected to public networks NW 1  and NW 2  via office lines L, respectively.  
      The main apparatuses BT 1 -BTn each have normal exchange control functions regarding mutual originating/incoming calls among the telephone terminals T 11 -T 1   i , T 21 -T 2   m , T 31 -T 3   p  and Tn 1 -Tnk, and among public networks NW 1 , NW 2  and the telephone terminals T 11 -T 1   i , T 21 -T 2   m , T 31 -T 3   p  and Tn 1 -Tnk.  
      The main apparatuses BT 1 -BTn are divided into extension groups G 1  and G 2 . The main apparatuses BT 1 , BT 2  and BT 3  belong to the extension group G 1  and the main apparatuses BT 4 -BTn belong to the extension group G 2 . In the extension group G 1 , the main apparatus BT 1  operates as a master unit and the main apparatuses BT 2  and BT 3  each operate as slaves.  
       FIG. 2  is a functional block diagram showing a connection configuration between the main apparatus BT 1  operating as the master unit and the main apparatus BT 2  operating as the slave unit. Wherein, the main apparatus BT 2  will be described as a representative of the slave units.  
      The main apparatus BT 1  consists of an agent group management unit  11  (hereinafter referred to as management unit  11 ), a network login communication unit  12  (hereinafter referred to as communication unit  12 ), an incoming cal distribution unit  13 , a network terminal state communication unit  14  (hereinafter referred to as communication unit  14 ), and an overflow control unit  15 .  
      The management unit  11  manages a management table  111  and a transfer destination table  112 . The management table  111  stores, as shown in  FIG. 3 , correspondence relationships among the extension group G 1 , the main apparatuses BT 1 , BT 2 , BT 3  belonging thereto, and the telephone terminals T 11 -T 3   p  belonging to the extension group G 1  and being in login states, namely activation states. The transfer destination table  112  stores correspondence relationships among the extension group G 1 , a plurality of telephone terminals that are the incoming call transfer destinations and their priority order.  
      The communication unit  12  communicates with the main apparatus BT 2  via the private network  1 , receives login state update information transmitted from the main apparatus BT 2  and updates registration information of the management table  111  of the management unit  11  in response to the update information.  
      When an incoming call from the public network NW  1  arrives, the incoming call distribution unit  13  inquires reception priorities to the telephone terminals T 21 -T 2   m  being in login states by referring to the management table  111  and transfers the incoming call to the telephone terminal decided as the incoming call destination.  
      The communication unit  14  communicates with the main apparatus BT 2  via the private network  1  and receives the terminal state update information transmitted from the main apparatus BT 2 .  
      The overflow control unit  15  communicates with the main apparatus BT 2  via the private network  1 , transmits overflow incoming call information to the main apparatus BT 4  belonging to a group other than the extension group G 1  and receives incoming result information corresponding to the overflow incoming call information.  
      In contrast, the main apparatus BT 2  consists of a network login communication unit  21  (hereinafter referred to as communication unit  21 ), a network terminal state communication unit  22  (hereinafter referred to as communication unit  22 ) and an incoming call control unit  23 .  
      The communication unit  21  makes a communication with the main apparatus BT 1  via the private network  1 , and when the telephone terminals T 21 -T 2   m  are brought into login states, it transmits login state update information.  
      The communication unit  22  transmits the terminal state update information to the main apparatus BT 1  when the telephone terminals T 21 -T 2   m  are brought into free states from calling states.  
      The incoming call control unit  23  performs a communication with the main apparatus BT 1  via the private network  1 , determines the incoming call priorities of the telephone terminals T 21 -T 2   m  in response to agent incoming call information transmitted from the main apparatus BT 1  to transmit the determination result, and further transmits the incoming call result relating to the overflow incoming call information.  
      Next, operations of the telephone system configured as given above will be described.  
       FIG. 5  is a schematic sequence view showing transmission/reception operations of information between the main apparatus BT 1  and the main apparatus BT 2  in performing login state update.  
      The main apparatus BT 1  registers the extension group G 1  and the telephone terminals T 21 -T 2   m  of the main apparatus BT 2  on the private network  1  as agent terminals in the identical group G 1  and stores registration information in the management table  111  managed by the management unit  11 .  
      With login operations of the telephone terminals T 21 -T 2   m  of the main apparatus Bt 2  as the slave unit for the main apparatus BT 1 , the communication unit  21  transmits the login state update notice to the main apparatus BT 1 , which is the master unit, via the private network  1 .  
      In the main apparatus BT 1 , the communication unit  12  receives the login state update information from the main apparatus BT 2  via the private network  1  to update the registered information in the management table  111  managed by the management unit  11  in accordance with the agent terminal information added to the received information.  
      As described above, in the first embodiment, the telephone system is constituted in that the extension group G 1  is associated with the main apparatuses BT 1 , BT 2  and BT 3  in advance, and also the management table  111  showing the correspondence relationships among a plurality of telephone terminals T 11 -T 1   i , T 21 -T 2   m , T 31 -T 3   p  and their login states in the extension group G 1  are stored only in the main apparatus BT 1  operating as the master unit, and each other main apparatus BT 2  and BT 3  monitors the login states of the telephone terminals T 21 -T 2   m  and T 31 -T 3   p  by itself, respectively, to notify the login state information of the logged-in telephone terminals T 21 -T 2   m  and T 31 -T 3   p  to the main apparatus BT 1 .  
      Accordingly, for instance, the main apparatus BT 1  to be used for maintenance becomes possible to integrally manage the login states of the telephone terminals T 11 -T 1   i , T 21 -T 2   m  and T 31 -T 3   p  housed respectively in the whole of the main apparatuses BT 1 , BT 2  and BT 3  in the extension group G 1 . When it becomes necessary for updating the management table  111  installed in the main apparatus BT 1  due to a change in the system, the main apparatus BT 1  can perform update control of the management table  111  for each group. Therefore, in the case of sharing a single private network  1  with a lot of main apparatuses BT 1 -BTn, there is no need to make each main apparatus BT 1 -BTn has the management tables  111 , respectively, thereby the system can reduce loads accompanied by update control of the management table  111  to enable simplify maintenance work thereof.  
     Second Embodiment  
       FIG. 6  is a schematic sequence view showing transmission/reception operations of information between the main apparatus BT 1  and the main apparatus BT 2  in performing the ACD in the second embodiment of the present invention. Here, it will be described in an assumption that the telephone terminals T 11 -T 1   i  housed in the main apparatus BT 1  are in the not-logged in states. In  FIG. 6 , the same units as those of  FIG. 2  will be put the same symbols and their detailed description will be omitted.  
      In the main apparatus BT 1 , when an incoming call directed to the extension group G 1  has arrived, the incoming call distribution unit  13  inquires, for instance, a login state of the telephone terminal  21  to finally decide an incoming call destination for the logged in state telephone terminal T 21  in accordance with a equal distribution system, and transmits agent incoming call information to the main apparatus BT 2  via the private network  1 .  
      In the main apparatus BT 2 , the incoming call control unit  23  receives the agent incoming call information from the main apparatus BT 1  via the private network  1 , determines an incoming call destination agent terminal, namely a free/occupied state, presence/absence of incoming call rejection setting and a failure state of the telephone terminal T 21 , and transmits incoming call result information regarding the agent terminal to the main apparatus BT 1  via the private network  1 .  
      In the main apparatus BT 1 , the incoming call distribution unit  13  analyzes the incoming call result information received from the main apparatus BT 2  via the private network  1  inquires the login state of the telephone terminal  22  in accordance with the equal distribution system when the incoming call is not allowed, and finally decides the incoming call destination for the logged in state agent terminal to transmit the agent incoming call information to the main apparatus BT 2  via the private network  1  again.  
      When finally receiving the allowance of the incoming call as the incoming call result information to the agent terminal, namely the telephone terminal T 22 , the main apparatus BT 1  terminates the equal distribution processing by the incoming call distribution unit  13 .  
      As mentioned above, in the second embodiment, when the incoming call directed to the extension group G 1  through the public network NW 1 /NW 2  has arrived, the system can perform incoming call distributions to a plurality of telephone terminals T 11 -T 3   p  for each group by referring to the management table  111 .  
      Conventionally, although the ACD to the agent terminals belonging to the agent group is limited to the main apparatuses belonging to the same agent group, it becomes possible to perform the ACD to any agent belonging to the main apparatuses BT 2  and BT 3  on the same private network  1  as that of the main apparatus BT 1  as the master unit with the agent group set thereto.  
     Third Embodiment  
       FIG. 7  is a schematic sequence view showing transmitting/receiving operations of information between the main apparatus BT 1  and the main apparatus BT 2  in performing the ACD and waiting a free telephone terminal, as a third embodiment of the present invention. Here, to explain the third embodiment, it is presumed that the telephone terminals T 11 -T 1   i  housed in the main apparatus BT 1  are in not logged-in stats. In  FIG. 7 , the same units as those of  FIG. 2  will be put the same reference symbols and their detailed description will be omitted.  
      When whole of the incoming call result information from the main apparatus BT 2  finally becomes unable to be received by the agent terminal, namely telephone terminals T 21 -T 2   m  and when there is no agent terminal possible to receive incoming calls, the main apparatus BT 1  makes the incoming calls cue to an agent group. In other words, the main apparatus BT 1  holds temporarily the incoming calls in a prescribed memory  16  in the main apparatus BT 1 .  
      For instance, when the telephone terminal T 22  during calling in the main apparatus BT 2  has terminates its calling to transit into an incoming call receivable state, a network terminal state communication unit  22  transmits the state update information of the telephone terminal T 22  to the main apparatus BT 1  via the private network  1 .  
      In the main apparatus BT 1 , the communication unit  14  receives the agent terminal state update information from the main apparatus BT 2  via the private network  1 , and when the communication unit  14  is in an incoming call receivable state, it transmits the agent incoming call information to the main apparatus BT 2  that is a slave unit via the private network  1 .  
      After this, the main apparatus BT 1  transfers the incoming call held in the memory  16  to a free telephone terminal T 22  to receive it.  
      As mentioned above, in the third embodiment, when the incoming call directed to the extension group G 1  has arrived, in the case where all the telephone terminals T 11 -T 3   p  belonging to the relevant extension group G 1  are busy, the main apparatus BT 1  does not notify the fact that telephone call cannot be made to any telephone terminals T 11 -T 3   p  to a call originating source but stores the incoming call in the memory  16  temporarily, then when the telephone terminal  22  in the extension group G 1  becomes free, the main apparatus BT 1  makes the free telephone terminal T 22  receive the incoming call stored in the memory  16 .  
      Accordingly, there is not need for the system to perform transmission operations again from the beginning on an originating side, and the system can surely make the telephone terminal T 22  in the extension group G 1  receive the incoming call.  
     Fourth Embodiment  
       FIG. 8  is a schematic sequence view showing transmitting/receiving operations of information between the main apparatus BT 1  and the main apparatus BT 4  in performing the ACD and performing incoming call transfer without a presence of any free telephone terminal. It is supposed that the main apparatus BT 4  is constituted in a similar manner to the aforementioned main apparatus BT 2 .  
      The main apparatus BT 1  stores incoming calls in the memory  16  to wait until any of the telephone terminals T 21 -T 2   m  of the main terminal BT 2  and the telephone terminals T 31 -T 3   p  of the main terminal BT 3  will be free.  
      However, it is presumed that the telephone terminals T 21 -T 2   m  of the main terminal BT 2  and the telephone terminals T 31 -T 3   p  of the main terminal BT 3  will not be free after the elapse of a fixed time period. Then, in the main apparatus BT 1 , the overflow control unit  15  refers to the transfer destination table  112  to determine whether or not the incoming call transfer destinations to the extension group G 1  have been registered. As shown in  FIG. 4 , the incoming call transfer destinations to the extension group G 1  having been registered, the main apparatus BT 1  transmits overflow incoming call information to the main apparatus BT 4  via the private network  1  in order to transfer the incoming call to a telephone terminal T 41  with the first priority order among the transfer destinations.  
      In the main apparatus BT 4 , the incoming call control  23  analyzes overflow incoming call information received from the main apparatus BT 1  via the private network  1 , determines a free/busy state, presence/absence of incoming call rejection, and failure state of the telephone terminal T 41  to be overflow incoming call destination terminal, and transmits incoming call result information relating to the telephone terminal T 41  to the main apparatus BT 1  via the private network  1 .  
      The main terminal BTI makes the overflow control unit  15  perform processing in response to the incoming call result information of the telephone terminal T 41  received from the main terminal BT 4  via the private network  1 . In the case that the incoming call is receivable, the main apparatus BT 1  transfers the incoming calls stored in the memory  16  to a telephone terminal T 41  to make it perform incoming call notice.  
      When the overflow incoming call destination terminal is in calling, in the event of an incoming call rejection, or an occurrence of a failure, so that the main apparatus BT 1  transfers the incoming call to a telephone terminal T 52  of the main apparatus BT 5  with the next priority order, the main apparatus BT 1  transmits the overflow incoming call information again to the main apparatus BT 5  via the private network  1 .  
      The main apparatus BT 1  determines whether or not any free telephone terminal is present within a fixed time period by means of a timer (not shown). The time clocking by the timer is performed in response to the times preset for each extension group.  
      As mentioned above, in the fourth embodiment, the system can automatically transfer incoming calls stored in the memory  16  to other incoming call receivable telephone terminal T 41  to receive them if, for instance, all the telephone terminals T 11 -T 1   i , T 21 -T 2   m  and T 31 -T 3   p  belonging to the extension group G 1  are busy and any telephone terminal will not become free even after the elapse of the fixed time period. Therefore, the incoming calls do not occupy the memory  16  in the extension group G 1 , and then, the system can enhance an effective use rate of the memory  16 . Thereby, the system becomes possible to flexibly control the incoming calls.  
      In the main apparatus BT 1 , if a plurality of overflow destinations, namely incoming call transfer destinations are present, having registered the transfer destinations in the transfer destination table  112  in priority order and having selected telephone terminals with higher priority order among these transfer destinations to receive the incoming call, even if the telephone terminal T 41  of the transfer destination with higher priority order is in calling, the main apparatus BT 1  can select the telephone terminal T 52  with the next high priority order to receive the incoming call.  
     Other Embodiment  
      The present invention is not limited to aforementioned embodiments. For instance, having described the example to specify the telephone terminal as the incoming call transfer destination in the fourth embodiment; the present invention is not limited such case, and it may specify a group as the incoming call transfer destination.  
      In the forth embodiment, having described the example to store the plurality of the telephone terminals as the incoming call transfer destinations together with the priority order, the incoming call transfer destination may be a single telephone terminal or a single group.  
      Further, each embodiment having been configured so as to assign the main apparatuses operating as the master units for each extension group, the present invention may divide a plurality of main apparatuses operating as slave units into the extension groups to manage each extension group by one set of the main apparatus as the master unit.  
      Other than this, it is possible to make a variety of modifications to implement the system configuration, the configuration of the main apparatus as the master unit, the configuration of the main apparatus as the slave unit, the types of the communication networks such as private networks, the kinds of the telephone terminals, the control procedures of each control and its control content without departing from the aspect of the invention.  
      While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.