JP7620260B2 - Emergency call device - Google Patents

Description

This invention relates to an emergency call device that makes emergency calls to emergency call receiving organizations such as police agencies, fire departments, and the Japan Coast Guard.

For example, there is known an emergency notification device that makes an emergency call to a designated emergency call receiving agency such as a fire department when an emergency such as a fire occurs. When a caller presses a call button, the emergency notification device calls the emergency call receiving agency, connects a call line (telephone line), and automatically reports the occurrence of an emergency using a pre-prepared voice message. The emergency call receiving agency then calls back to, for example, a dedicated call telephone (hereinafter referred to as a dedicated telephone) connected to the emergency notification device. In response to this, the caller can pick up the handset of the dedicated telephone, which rings, and then go off-hook to connect the call line between the dedicated telephone and the emergency call receiving agency, allowing the call to be made.

If the emergency call device is connected to a fixed telephone network (PSTN (Public Switched Telephone Network)), the call line between the emergency call receiving agency and the emergency call device is put on hold after an emergency call is made. In other words, if the emergency call device is connected to a fixed telephone network, the line is put on hold even if the caller hangs up when making a special number call. For this reason, when the emergency call receiving agency calls back, a call signal (a so-called IR signal) is sent from the fixed telephone network as a call-back signal (hereinafter referred to as a return call signal), and the dedicated telephone rings. In response, by picking up the handset of the dedicated telephone, it becomes possible to talk to a person at the emergency call receiving agency.

However, in recent years, it has become possible to use IP (Internet Protocol) networks instead of fixed-line telephone networks, and it is planned to transition all fixed-line telephone networks to IP networks in the near future. An IP network refers to a network that is interconnected using the Internet Protocol Suite technology (TCP/IP). When emergency call devices connected to an IP network are operated, the line hold function after an emergency call is no longer available, and a method is adopted in which the call line is connected and a conversation with the caller is made by calling back (calling back) to a dedicated telephone.

In this case, if an emergency call is made from an emergency call device connected to an IP network via a subscriber telephone line that has a contract for a service that notifies the caller's number when a call is received, the dedicated telephone will not be able to receive a callback from the emergency call receiving agency. Note that the service that notifies the caller's number when a call is received (caller number notification service) is known as number display (registered trademark) and is provided by telephone companies.

Let's say an emergency call is made from an emergency call device connected to an IP network through a subscriber telephone line that has a contract for the caller ID service, and the emergency call receiving agency calls back to the caller. In this case, an information receiving terminal activation signal (a so-called CAR signal) is sent from the IP network, which activates the caller ID service-compatible function of the called telephone terminal. Next, if there is a response from the called telephone terminal, the IP network sends the caller ID as a modem signal, which notifies the called telephone terminal of the caller ID and displays it, and then an IR signal is sent to call the called telephone terminal. Note that if there is no response from the called telephone terminal within six seconds after the CAR signal is sent, the IP network automatically sends an IR signal.

Needless to say, dedicated telephones do not support caller ID services because they are intended to enable calls during emergency calls. For this reason, in response to a callback from an emergency call receiving agency, the dedicated telephone rings with the first CAR signal that arrives, and the dedicated telephone goes off-hook in response. In this case, the caller number arrives immediately afterwards, and since it cannot respond to the IR signal that arrives after this, it is not possible to connect a call line between the emergency call receiving agency and the dedicated telephone. The applicant of this application has previously filed an invention to solve this problem, and this application has already been published as Patent Document 1, which will be described later.

Patent Document 1 discloses an invention in which a dedicated telephone does not ring when a CAR signal arrives, but rings when an IR signal arrives, thereby connecting a telephone line to an emergency call receiving agency and enabling a call. Note that a CAR signal is a signal that has one cycle of 1 second, with a 0.5 second on and 0.5 second off sequence. Also, an IR signal is a signal that has one cycle of 3 seconds, with a 1 second on and 2 seconds off sequence. Also, a modem signal is a signal in which a data signal is carrier modulated into an AC waveform within the voice band.

JP 2018-50170 A

As mentioned above, in the operation of emergency call devices connected to IP networks, the function of putting the line on hold after an emergency call is no longer available, and the adoption of a method that connects the telephone line and enables a conversation with the caller by calling back has revealed the existence of further issues that need to be resolved. Specifically, if an IR signal, which is a call signal, arrives in response to a callback operation, and then the IR signal is cut off (disappears) for some reason, if you go off-hook (answer the call), you may not be able to talk to the emergency call receiving agency.

In an emergency call system, the IR signal sent to the emergency call source in response to a callback operation by the emergency call receiving agency continues to be sent until the call from the emergency call receiving agency stops or the telephone connected to the emergency call device is taken off-hook. For ease of explanation, the IR signal, which is a call signal sent to the emergency call device of the emergency call source in response to a callback operation by the emergency call receiving agency, will be referred to as a "return call signal."

Possible causes of the interruption of the incoming IR signal after a callback operation include a malfunction of the gateway device that connects the emergency call device to the IP network, a malfunction in the IP network system, or a malfunction of the command desk system at the emergency call receiving agency. A malfunction in the command desk system could be, for example, a high number of emergency calls (emergency calls), which can cause the system to exceed its capacity and result in a malfunction. It is also possible that the line may be disconnected due to an incorrect operation of the command desk.

When a call back signal arrives, the telephone connected to the emergency notification device rings, and by picking up the receiver of the telephone in response to this, the telephone is connected to the IP network and a call can be made. However, suppose that the IR signal is interrupted (disappears) due to the event described above before the telephone rings in response to the call back signal and the off-hook operation is made. In this case, since the call back signal has been interrupted, the call line will not be connected even if the telephone is off-hook. Furthermore, if the telephone remains off-hook, the call will be in progress (busy), and the call line cannot be connected even if the IR signal returns. Even in such a case, due to the nature of the emergency notification device, it is desirable to reliably connect the call line and make it possible to make a call.

In view of the above, the object of this invention is to enable an emergency call device connected to an IP network to properly connect a call line to an emergency call receiving agency even if the call back signal is interrupted after the call back signal arrives.

In order to solve the above problems, the emergency call device of the present invention as set forth in claim 1 comprises:
An emergency call device that makes an emergency call to a predetermined emergency call receiving agency through an IP (Internet Protocol) network,
a callback signal discrimination means for discriminating whether or not a callback signal is transmitted in response to a callback operation at the emergency call receiving agency after the emergency call is made;
A switching means for switching between connection/disconnection between a telephone connected to the device and the IP network;
and a pull-in control means for switching the switching means to a non-connected state when the result of the discrimination in the reverse signal discrimination means changes from the presence of the reverse signal to its disappearance.

According to the emergency call device of the invention described in claim 1, the emergency call device is capable of connecting to an emergency call receiving agency through an IP network, and after an emergency call, the presence or absence of a return call signal is determined by the return call signal determination means. When the determination result of the return call signal determination means changes from the presence of a return call signal to its disappearance, the switching means is switched to a non-connected state by the retraction control means.

According to this invention, even if the telephone that rang due to the arrival of the back signal after an emergency call is disconnected before the telephone is off-hooked and then off-hooked, the telephone and the IP network can be disconnected and the line route can be drawn into the emergency call device. As a result, in the emergency call device connected to the IP network, the back signal that arrives again after the incoming back signal has stopped is connected to the telephone, so that the call line can be properly connected to the emergency call receiving agency.

1 is a block diagram for explaining a configuration example of an emergency notification device according to an embodiment; 2 is a block diagram for explaining the operation of the emergency notification device according to the embodiment; FIG. 4 is a sequence diagram for explaining the operation of an emergency call system including the emergency call device of the embodiment. FIG. FIG. 4 is a sequence diagram following FIG. 3 for explaining a case where a telephone line is normally connected in response to the arrival of a return signal. FIG. 4 is a sequence diagram following FIG. 3 for explaining a case where the call back signal is interrupted after arrival of the call back signal and the telephone line cannot be connected. FIG. 4 is a sequence diagram following FIG. 3 for explaining a case in which the telephone line can be connected even if the telephone is off-hook after the return signal arrives and then stops. 4 is a flowchart illustrating a process executed by the emergency notification device according to the embodiment.

Below, with reference to the drawings, an embodiment of the emergency call device according to the present invention will be described. After making an emergency call to an emergency call receiving agency through the emergency call device, there is a possibility that the return signal that arrives as a result of a callback operation at the emergency call receiving agency may be interrupted for some reason, as described above. The emergency call device of the embodiment described below is capable of appropriately connecting a call line in response to a return signal that arrives after an off-hook operation is performed through a telephone connected to the device itself after the return signal has been interrupted, even if the off-hook state is maintained.

The emergency call receiving organization to which an emergency call is made is generally a police agency, the Japan Coast Guard, a fire department, etc., but it is of course possible for any other organization, such as a security company, to be the emergency call receiving organization. In the embodiment described below, for the sake of simplicity, the emergency call device reports the occurrence of a fire, and the emergency call receiving organization is a fire department, as an example.

[Configuration example of emergency notification device 1]
Fig. 1 is a block diagram for explaining an example of the configuration of an emergency call device 1 according to this embodiment. As shown in Fig. 1, the emergency call device 1 is capable of making an emergency call by connecting a telephone line to an emergency call receiving agency 5 via an IP network 4. The IP network 4 means a network interconnected using TCP/IP, and includes all of the facilities related to communication on the telephone company side.

In addition, in this specification, a gateway (analog line conversion device) 3 is connected to the IP network 4, and the emergency call device 1 is connected to the IP network 4 via the gateway 3. Therefore, the emergency call device 1 and the gateway 3 are connected by an analog line. In FIG. 1, the gateway 3 is abbreviated as GW3. In addition, in this embodiment, for the sake of simplicity, it is assumed that the emergency call device 1 is connected to the IP network 4 through a subscriber telephone line that does not have a caller ID service contract.

A telephone 2 is connected to the emergency call device 1 in this embodiment. The telephone 2 is for answering calls made during emergency calls in response to a callback from an emergency call receiving agency. The telephone 2 may be a dedicated telephone used only for emergency calls, or it may be a general telephone connected to the emergency call device 1 and also to a main device such as a SIP server (not shown). Therefore, the general telephone is capable of answering calls made during emergency calls, and is normally connected to an IP network via the main device, and is capable of making calls to the intended recipient and answering incoming calls.

As shown in FIG. 1, the emergency notification device 1 includes a line control unit 101, a telephone control unit 102, a CPU unit 103, and a notification button 104. The line control unit 101 controls the connection of the line through the IP network 4, and includes a call back signal discrimination unit 1011, a pull-in control unit 1012, a response/disconnection control unit 1013, and a notification control unit 1014. The telephone control unit 102 controls the connection between the line connected to the emergency notification device 1 and the telephone 2, and includes a call control unit 1021, a switching unit 1022, and a hook state detection unit 1023.

The CPU unit 103 is a main control unit that controls each part of the emergency notification device 1, and is configured with a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), non-volatile memory, etc., although not shown. The notification button 104 is a button switch that is pressed by the caller. When the notification button 104 is pressed, a predetermined electrical signal is supplied to the CPU unit 103, and the CPU unit 103 is notified that the notification button has been operated.

When the report button 104 is pressed, the CPU unit 103 instructs the line control unit 101 to make an emergency report. In response, the report control unit 1014 functions and makes an emergency report to the emergency report receiving agency 5, which is a fire department in this embodiment. The response/disconnection control unit 1013 responds to a control signal from the report control unit 1014 by returning a response to the IP network 4 and disconnecting the connected line.

Specifically, the response/disconnection control unit 1013 connects the telephone line when an emergency call (alert) is made through the notification control unit 1014. Thereafter, under the control of the notification control unit 1014, the response/disconnection control unit 1013 transmits, for example, a notification message prepared in the non-volatile memory of the CPU unit 103 to the emergency call receiving agency 5. After the response/disconnection control unit 1013 has finished transmitting the notification message, it releases the telephone line connected to the emergency call receiving agency 5. In this way, the emergency call is made, and after the notification message is sent, the connected telephone line is released and the system waits for the arrival of a return call signal.

After an emergency call is made, the back-call signal discrimination unit 1011 determines whether a back-call signal addressed to the device itself, which is transmitted through the IP network 4, has arrived in response to a callback operation at the emergency call receiving agency 5, and whether the arriving back-call signal has ceased (disappeared). In other words, the back-call signal discrimination unit 1011 distinguishes between the arrival and disappearance of a back-call signal addressed to the device itself. The discrimination result by the back-call signal discrimination unit 1011 is notified to the CPU unit 103.

When the return call signal discrimination unit 1011 detects the arrival of a return call signal addressed to the device itself, the CPU unit 103 controls the lead-in control unit 1012 (described later) to switch the switching unit 1022 (described later) to the connected state (on state). Also, under the control of the CPU unit 103, the call control unit 1021 of the telephone control unit 102 functions to ring the telephone 2 connected to the emergency notification device 1. In this way, the call control unit 1021 controls the telephone 2 to ring (ring for incoming call) to notify that there is a call (an incoming call). When the telephone 2 rings for an incoming call, the user of the telephone 2 (usually the caller who pressed the call button 104) performs an off-hook operation to pick up the receiver of the telephone 2.

The hook state detection unit 1023 of the telephone control unit 102 detects the hook state of the telephone 2 and notifies the CPU unit 103 of the detection result, and also controls the switching unit 1022 to switch to the off state (disconnected state) when the telephone 2 goes from an off-hook state to an on-hook state. The switching unit 1022 switches between connection/disconnection between the telephone 2 and the IP network 4. As described above, when a return signal arrives, the switching unit 1022 is switched to the on state (connected state) by the retraction control unit 1012 in response to the control of the CPU unit 103. Also, as described above, when the telephone 2 goes from an off-hook state to an on-hook state, the switching unit 1022 is switched to the off state (disconnected state) by the control of the hook state detection unit 1023.

Therefore, as described above, after an emergency call is made, when a callback signal arrives in response to a callback operation at the emergency call receiving agency, this is discriminated by the callback signal discriminator 1011 and notified to the CPU 103. The CPU 103 controls the lead-in controller 1012 to switch the switch 1022 to the on state, and controls the call controller 1021 of the telephone controller 102 to ring the telephone 2.

As a result, when the telephone 2 is taken off-hook, the telephone 2 is connected to the IP network 4, and the telephone line is seized, the telephone 2 is connected to the emergency call receiving agency 5, and a call can be made, and a person at the emergency call receiving agency 5 listens in on the situation. In this way, in response to the arrival of a call back signal, the telephone 2 is connected to the call line and a call can be made. After this, when the call ends and the telephone 2 is put on-hook, this is detected by the hook state detection unit 1023, which then returns the switching unit 1022 to the off state. This makes it possible to respond to the arrival of another call back signal.

However, after the arrival of the back signal, it may be interrupted (lost) due to some malfunction, such as a malfunction of the gateway 3, a malfunction of the network system, a malfunction of the command desk system, or an incorrect operation of the command desk. The user of the telephone set 2 has no way of knowing that the back signal has disappeared. In this case, even if the user goes off-hook on the telephone set 2 in response to the ringing notifying the incoming call, the back signal has been interrupted and the call line cannot be connected.

Also, if the phone remains off-hook, the incoming call signal turns on the switching unit 1022, and the on state is maintained. In this case, the telephone set 2 remains connected to the IP network 4, and the call line cannot be connected even if the incoming call signal returns. Therefore, in the emergency notification device 1, the call signal discrimination unit 1011, the lead-in control unit 1012, and the CPU unit 103 cooperate to control the switching unit 1022, thereby preventing a problem in which the call line cannot be connected when the incoming call signal is interrupted (disappears).

[Operation of emergency notification device 1]
The operation of the emergency call device will be described below with reference to Figures 2 to 6. First, a case where the telephone line is normally connected in response to a call back signal from an emergency call will be described below, followed by a case where the call back signal is interrupted after the call back signal arrives and the telephone line cannot be connected. After that, a case where the application of the present invention allows the telephone line to be connected even if the call back signal is interrupted after the call back signal arrives will be described.

<Operation when a call line is normally connected through the emergency call device 1>
Fig. 2 is a block diagram for explaining the operation of the emergency notification device 1 of this embodiment. In Fig. 2, the switching unit 1022 of the telephone control unit 102 is shown as a switch circuit configuration to easily show its function, but it can be variously configured to switch between connection/disconnection between the telephone 2 and the IP network 4. Fig. 3 is a sequence diagram for explaining the operation of the emergency notification system including the emergency notification device 1 of this embodiment, and Fig. 4 is a sequence diagram following Fig. 3 for explaining the case where the call line is normally connected in response to the arrival of a return signal. In Fig. 3, the "gateway" is abbreviated as "GW".

As described above, assume that the call button 104 of the emergency call device 1 is pressed (step S1). In this case, in response to a control signal from the CPU 103, the call control unit 1014 functions to seize the line (step S2) and dials and transmits a call to a specific emergency call receiving agency 5 (step S3). In response, the gateway 3 sends a call signal to the emergency call receiving agency 5 to the IP network 4 (step S4), and the IP network 4 transmits a bell ringing signal to the emergency call receiving agency 5 (step S5).

When the command desk of the emergency call receiving agency 5 receives a bell ringing signal from the IP network, it rings to notify the occurrence of an emergency call (step S6), and the person in charge of the emergency call receiving agency 5 performs a reception operation on the command desk (step S7). The command desk of the emergency call receiving agency 5 that has received the reception operation sends a reception signal to the IP network 4 (step S8), and the IP network 4 forms a response signal and sends this to the emergency call device 1, which is the source of the call (step S9). When the gateway 3 receives the response signal from the IP network 4, it forms a response signal (analog signal) to be provided to the emergency call device 1, and sends this to the emergency call device 1 (step S10).

The response/disconnection control unit 1013 of the emergency call device 1 responds to the response signal from the gateway 3, connects a telephone line between the device itself and the emergency call receiving agency 5, and makes a guidance call (step S11). In step S11, under the control of the call control unit 1014, the response/disconnection control unit 1013 transmits a call message (audio signal) stored in the non-volatile memory of the CPU unit 103 to the emergency call receiving agency 5. The call message notifies, for example, the occurrence of an incident (such as a fire), an address, a telephone number, etc., as audio. As a result, the emergency call receiving agency 5 emits the call message (step S12), which can be recognized by the person in charge at the emergency call receiving agency 5.

When the transmission of the notification message is completed, the response/disconnection control unit 1013 of the emergency notification device 1 releases (disconnects) the telephone line connected in step S11 (step S13). In response, the gateway 3 sends a disconnection signal to the IP network 4 (step S14), and the IP network 4 sends a disconnection signal to the emergency notification receiving agency 5 (step S15). Note that the disconnection signal sent from the IP network 4 to the emergency notification receiving agency 5 may be any signal indicating that the connected telephone line has been disconnected, for example, by agreement, and may be, for example, a busy tone that is used when the telephone line is disconnected.

When the emergency call receiving agency 5 receives the disconnection signal, a callback request message is emitted requesting the person in charge of the emergency call receiving agency 5 to call back the emergency call originator (step S16). In response, the person in charge of the emergency call receiving agency 5 performs a callback operation on the command console (step S17). The command console of the emergency call receiving agency 5 transmits a callback signal to the IP network 4 instructing the person in charge of the emergency call originator to call back (step S18).

When the IP network 4 receives a callback signal from the emergency call receiving agency 5, it forms an incoming call signal (incoming call request) and sends it to the gateway 3 to which the emergency call device 1 is connected (step S19). The gateway 3 forms a call signal (IR signal) from the incoming call signal and sends it as a call back signal to the emergency call device 1 (step S20). As shown in FIG. 3, after an emergency call, the period (time) required from when the emergency call device 1 releases the line in step S13 until the emergency call device 1 receives the call back signal in step S20 is set to within 10 seconds. Therefore, a time limit is also set for the period (time) from when the gateway 3 sends a disconnection signal in step S14 until the gateway 3 receives the incoming call signal in step S19.

In FIG. 4, which is a sequence diagram following FIG. 3, the sequence from step S20 shown at the bottom of FIG. 3 is described for ease of explanation. In the emergency notification device 1 that receives the call back signal, the call back signal discrimination unit 1011 discriminates the arrival of the call back signal and notifies the CPU unit 103, and the CPU unit 103 turns on the switching unit 1022 via the lead-in control unit 1012 (step S21), and then controls the call control unit 1021 to ring the telephone 2 (step S22).

When the user of the telephone 2 recognizes the incoming call by the ringing of the telephone 2 and performs an off-hook operation on the telephone 2 (step S23), the telephone 2 is connected to the IP network 4 and the call line is captured (step S24). As shown in FIG. 4, the emergency notification device 1 needs to capture the line in step S24 within a certain time after receiving the return call signal in step S20.

In response to the line capture in step S24, the gateway 3 sends a response signal to the IP network 4 to the emergency call receiving agency 5 that made the callback (step S25), and the IP network 4 sends a response signal to the emergency call receiving agency 5 (step S26). This connects a call line between the emergency call receiving agency 5 and the telephone 2 connected to the emergency call device 1 that made the emergency call (step S27). The person in charge of the emergency call receiving agency 5 can talk to the user of the telephone 2 (usually the caller) and ask about the situation (step S28). When the call between the person in charge of the emergency call receiving agency 5 and the user of the telephone 2 ends, for example, the user of the telephone 2 goes on-hook on the telephone 2.

This notifies the emergency call device 1 that the telephone 2 has gone on-hook (step S29). The hook state detection unit 1023 of the emergency call device 1 detects that the telephone 2 has gone on-hook and notifies the CPU unit 103 of this, while turning off the switching unit 1022 to disconnect the telephone 2 from the IP network 4 and release the communication line (step S30). In response to the line release in step S30, the gateway 3 sends a disconnection signal to the IP network 4 to the emergency call receiving agency 5 that is the callback source (step S31), and the IP network 4 sends a disconnection signal to the emergency call receiving agency 5 (step S32). The emergency call receiving agency 5 that receives the disconnection signal releases the communication line (step S33). This completes the series of call processing that began with the pressing of the call button 104.

<Operation when the return signal is cut off and the line cannot be connected>
Fig. 5 is a sequence diagram following Fig. 3 for explaining a case where the call back signal is interrupted after the arrival of the call back signal and the telephone line cannot be connected. In Fig. 5, the sequence from step S20 shown at the bottom of Fig. 3 is also described for the sake of simplicity. After the emergency call is made, a call back signal is sent in response to a callback from the emergency call receiving agency 5 by the series of processes described using Fig. 3 (step S20). In the emergency call device 1 that receives the call back signal, the call back signal discrimination unit 1011 discriminates the arrival of the call back signal and notifies the CPU unit 103, and the CPU unit 103 turns on the switching unit 1022 through the lead-in control unit 1012 (step S21), and controls the call control unit 1021 to ring the telephone 2 (step S22). Up to this point, the process is the same as that described using Fig. 4.

However, suppose that the call back signal that arrived in step S20 is interrupted (lost) due to some reason, such as a malfunction of the gateway 3, as described above (step S40). In this case, suppose that an off-hook operation is performed on the telephone 2 in response to the incoming call ringing in step S21 (step S51). However, since the call back signal has been lost, even if the line is captured (step S52), the call line cannot be connected to the emergency call receiving agency 5.

In addition, as a result of the return signal being cut off, a disconnection signal is sent from the gateway 3 to the IP network 4 (step S41), and a disconnection signal is sent from the IP network 4 to the emergency call receiving agency 5 that made the callback (step S42). In response, as in step S16 of FIG. 3, the emergency call receiving agency 5 issues a callback request message requesting the person in charge of the emergency call receiving agency 5 to call back the emergency caller (step S43). In response, the person in charge of the emergency call receiving agency 5 performs a callback operation on the command desk (step S44).

The command desk of the emergency call receiving agency 5 sends a callback signal to the IP network 4 to instruct the emergency caller to call back (step S45). When the IP network 4 receives the callback signal from the emergency call receiving agency 5, it creates an incoming call signal (incoming call request) and sends this to the gateway 3 to which the emergency call device 1 is connected (step S46). In this case, if the telephone 2 has been put on-hook and returned to the on-hook state, the hook state detection unit 1023 has returned the switching unit 1022 to the off state, and the line is released, the telephone 2 can be made to ring to ring again as described above.

However, since the user of the telephone 2 cannot know that the call back signal has disappeared, the user may wait with the telephone in an off-hook state. For this reason, in the example shown in FIG. 5, the telephone 2 connected to the emergency notification device 1 is in an off-hook state, and the switching unit 1022 is in an on state, so that the telephone 2 and the IP network 4 remain connected (line capture state) (step S52). For this reason, the gateway 3 cannot send a call back signal to the emergency notification device 1, and cannot connect a call line to the emergency notification receiving agency 5. Therefore, a call cannot be made between the person in charge of the emergency notification receiving agency 5 and the user of the telephone 2 connected to the emergency notification device 1, and the person in charge of the emergency notification receiving agency 5 cannot understand the situation. The emergency notification device 1 of this embodiment prevents such a situation from occurring.

<To enable connection of the line after the return signal is lost>
Fig. 6 is a sequence diagram following Fig. 3 for explaining a case where the telephone line can be connected even if the telephone is off-hook after the arrival of the return signal and the end of the return signal. For the sake of simplicity, Fig. 6 also shows the sequence from step S20 shown at the bottom of Fig. 3.

After the emergency call is made, a callback signal is sent in response to a callback from the emergency call receiving agency 5 through the series of processes described in FIG. 3 (step S20). In the emergency call device 1 that receives the callback signal, the callback signal discrimination unit 1011 discriminates the arrival of the callback signal and notifies the CPU unit 103, and the CPU unit 103 turns on the switching unit 1022 through the lead-in control unit 1012 (step S21), and controls the call control unit 1021 to ring the telephone 2 (step S22). However, as described above, the callback signal that arrived in step S20 is assumed to have been interrupted (disappeared) for some reason (step S40). These processes are the same as those described in FIG. 5.

However, in the case of the emergency notification device 1 of this embodiment, the return signal discrimination unit 1011 of the line control unit 101 determines that the received return signal has been interrupted (lost), and notifies the CPU unit 103. In this case, the CPU unit 103 controls the retraction control unit 1012 to turn off the switching unit 1022 of the telephone control unit 102 (step S61). This releases the connection between the telephone 2 and the IP network 4, so that even if the telephone 2 is put into an off-hook state (step S62), the line is not captured (step S63). Therefore, even if the telephone 2 is in an off-hook state, the emergency notification device 1 can respond to the return of the return signal.

In other words, as in the case described with reference to FIG. 4, when the return signal is interrupted (step S40), a disconnection signal is sent from the gateway 3 to the IP network 4 (step S41), and a disconnection signal is sent from the IP network 4 to the emergency call receiving agency 5 that made the callback (step S42). In response, the emergency call receiving agency 5 issues a callback request message requesting the person in charge of the emergency call receiving agency 5 to call back the emergency caller (step S43). The person in charge of the emergency call receiving agency 5 performs a callback operation on the command desk (step S44).

As a result, the command desk of the emergency call receiving agency 5 sends a callback signal to the IP network 4 instructing the emergency caller to call back (step S45). When the IP network 4 receives the callback signal from the emergency call receiving agency 5, it creates an incoming call signal (incoming call request) and sends this to the gateway 3 to which the emergency call device 1 is connected (step S46). In this case, even if the telephone 2 remains off-hook, the switching unit 1022 is turned off by the processing of step S61, and the call line is released. Therefore, the gateway 3 can send a call back signal to the emergency call device 1 (step S47).

Therefore, the return signal discrimination unit 1011 of the emergency notification device 1 detects the arrival of the return signal and notifies the CPU unit 103 and the lead-in control unit 1012 (step S64). Under the control of the CPU unit 103, the lead-in control unit 1012 switches the switching unit 1022 of the telephone control unit 102 to the ON state and captures the line (step S65). That is, in step S65, the switching unit 1022, which was turned OFF in step S61 due to the disappearance of the return signal, is turned ON in response to the return of the return signal. This causes the telephone set 2 to capture the line of the IP network 4.

In response to the line capture in step S65, the gateway 3 sends a response signal to the IP network 4 to the emergency call receiving agency 5 that made the callback (step S66), and the IP network 4 sends a response signal to the emergency call receiving agency 5 (step S67). This connects a call line between the emergency call receiving agency 5 and the telephone 2 connected to the emergency call device 1 that made the emergency call (step S68). A person in charge at the emergency call receiving agency 5 talks to the user of the telephone 2 (usually the caller) and asks about the situation (step S69).

The process thereafter is the same as that of steps S29 to S33 described with reference to FIG. 4. That is, when the call between the person in charge at the emergency call receiving agency 5 and the user of the telephone 2 ends, for example, the user of the telephone 2 puts the telephone 2 on-hook. This notifies the emergency call device 1 that the telephone 2 is on-hook (step S29). The hook state detection unit 1023 of the emergency call device 1 detects that the telephone 2 is on-hook and notifies the CPU unit 103 of this, while also turning off the switching unit 1022, disconnecting the telephone 2 from the IP network 4 and releasing the call line (step S30).

In response to the line release in step S30, the gateway 3 sends a disconnection signal to the IP network 4 to the emergency call receiving agency 5 that made the callback (step S31), and the IP network 4 sends a disconnection signal to the emergency call receiving agency 5 (step S32). The emergency call receiving agency 5 that receives the disconnection signal releases the call line (step S33). This completes the series of reporting processes that began with the pressing of the report button 104.

In this way, in the emergency notification device 1 of this embodiment, when a call back signal arrives after an emergency call, the lead-in control unit 1012 turns on the switching unit 1022, and when the telephone 2 is off-hook, the call line is immediately connected to enable a call. Furthermore, in the emergency notification device 1 of this embodiment, when the incoming call back signal is interrupted (disappeared) for some reason after an emergency call, the lead-in control unit 1012 turns off the switching unit 1022. This allows the line route to be drawn into the emergency notification device 1, making it possible to respond to the return of the call back signal.

[Summary of the processing of the emergency notification device 1]
Next, the processing performed by the emergency notification device 1 of this embodiment will be summarized with reference to the flowchart of Fig. 7. Fig. 7 is a flowchart for explaining the processing executed by the emergency notification device 1 of this embodiment, and the processing is executed by the CPU 103 of the emergency notification device 1 controlling each unit.

When the report button 104 is pressed, the CPU unit 103 starts the process shown in FIG. 7. As described with reference to FIGS. 2 and 3, the CPU unit 103 controls the report control unit 1014 and the response/disconnection control unit 1013 of the line control unit 101 to execute emergency report processing (step S101). By the process of step S101, the processes of steps S2 to S20 shown in FIG. 3 are performed in the emergency report system including the emergency report device 1.

After this, under the control of the CPU unit 103, the return signal discrimination unit 1011 of the line control unit 101 functions to receive the return signal, discriminates whether or not a return signal has arrived, and notifies the CPU unit 103 and the retraction control unit 1012 of the discrimination result (step S102). Based on the notification from the return signal discrimination unit 1011, the CPU unit 103 discriminates whether or not a return signal has arrived (step S103), and if it determines that a return signal has not arrived, it repeats the process from step S102 and waits for the arrival of the return signal.

When it is determined in the determination process of step S103 that a call back signal has arrived, the CPU unit 103 switches the switching unit 1022 to the on state through the lead-in control unit 1012 of the line control unit 101, and controls the call control unit 1021 of the telephone control unit 102 to ring the telephone 2 connected to the own device (step S104). After receiving the call back signal, the call back signal determination unit 1011 determines whether the received call back signal has disappeared or not, and notifies the CPU unit 103 of the determination result.

Therefore, the CPU unit 103 determines whether the received call back signal has disappeared based on the notification from the call back signal determination unit 1011 (step S105). If it is determined in the determination process of step S105 that the call back signal has not disappeared, the CPU unit 103 controls the hook state detection unit 1023 of the telephone control unit 102 to determine whether the telephone 2 connected to the own device has been put into an off-hook state (step S106). If it is determined in the determination process of step S106 that the telephone 2 has not been put into an off-hook state, the process from step S105 is repeated.

Let us assume that in the determination process of step S106, it is determined that the phone has been put into an off-hook state. In this case, since the power switching unit 1022 has been switched to the on state in step S104, the telephone 2 is connected to the IP network 4 and the line is seized (step S107). As a result, a call line is connected between the emergency call receiving agency 5 that is the callback source and the telephone 2 connected to the emergency call device 1, enabling a call (step S108).

After this, the CPU unit 103 controls the hook state detection unit 1023 of the telephone control unit 102 to determine whether the telephone 2 connected to the own device has been put into an on-hook state (step S109). If it is determined in the determination process of step S109 that the telephone 2 has not been put into an on-hook state, the call is still ongoing, so the process from step S109 is repeated to wait for the telephone 2 to be put into an on-hook state.

Let us assume that in the determination process of step S109, it is determined that the telephone 2 has been put into an on-hook state. In this case, the hook state detection unit 1023 of the telephone control unit 102 switches the switching unit 1022 off, releasing the line of the IP network 4 that the telephone 2 had captured (step S110), and the process shown in FIG. 7 is terminated. In this way, the processes of steps S101 to S110 are the processes executed by the emergency notification device 1 out of the processes shown in FIG. 3 and FIG. 4.

Also, suppose that in the judgment process of step S105, it is determined that the back call signal that had arrived at the own device has disappeared. In this case, since the switching unit 1022 is turned on in step S104, the telephone 2 is connected to the IP network 4 and the line is captured. However, since the back call signal has been interrupted at this point, even if the telephone 2 is taken off-hook, the call line cannot be connected. Also, if the telephone 2 is taken off-hook and remains in the off-hook state, the switching unit 1022 remains on. Therefore, the telephone 2 remains in a state of capturing the line of the IP network 4, and the call line cannot be connected even if the back call signal returns.

The CPU unit 103 then controls the pull-in control unit 1012 to switch the switching unit 1022 to the off state, and pulls in the line (step S111). That is, the process of step S111 cuts off the connection between the telephone 2 and the IP network 4, and pulls in the line route to the emergency call device 1. In this way, the process of step S111 is a process that enables the emergency call device 1 to receive (accept) a callback signal in response to a callback from the emergency call receiving agency 5. After this, the CPU unit 103 again waits for the arrival of a callback signal (steps S102, S103), and upon receiving the callback signal, performs the processes from step S104 onwards in the same manner as described above.

As a result, a call line is connected between the telephone 2 and the emergency call receiving agency 5 that originated the callback, and the CPU unit 103 performs processing from step S108, enabling a call between the person in charge of the emergency call receiving agency 5 and the user of the telephone 2. In this way, even if a call back signal that has arrived once is lost for some reason, the emergency call device 1 of this embodiment responds appropriately to the recurrence of the call back signal and connects the call line, ensuring that a call can be made between the person in charge of the emergency call receiving agency 5 and the user of the telephone 2.

In this case, even if telephone 2 remains off-hook, the switching unit 1022 returns from the off state to the on state, allowing the telephone line to be connected. Therefore, the user of telephone 2 can reliably communicate with the person in charge at the emergency call receiving agency 5 through the telephone line that is connected in response to the return of the call back signal.

[Effects of the embodiment]
The emergency call device 1 of the above embodiment can properly connect a telephone line between the telephone 2 connected to itself and the emergency call receiving agency 5 to make a call even if the call back signal is interrupted after the call back signal arrives. In this case, the user of the telephone 2 connected to the emergency call device 1 can automatically respond to the returning call back signal to quickly connect the telephone line and make a call with a person in charge at the emergency call receiving agency 5. This can further improve the reliability of the emergency call device 1 that is used while connected to the IP network 4.

[Modifications, etc.]
The emergency notification device 1 of the above embodiment has been described as making an emergency notification when the notification button is pressed, but the present invention is not limited to this. For example, in the case of an emergency notification device that reports the occurrence of a fire, the device may be configured to make a notification when a fire is detected by a heat sensor or a smoke sensor. Also, the device may be configured to make a notification when a suspicious person's intrusion is detected by a human presence sensor that detects the intrusion of a suspicious person. In this way, the emergency notification device may of course make an emergency notification when an emergency occurrence is detected by various sensors, not just when the notification button is pressed.

In the above embodiment, the emergency notification device 1 is described as being connected to a telephone 2. However, this is not limited to this. The emergency notification device 1 can be configured to be connected to either or both of a dedicated telephone and a general telephone. Simply put, it can be configured to connect a call line between the emergency notification device 1 and a telephone that is off-hook when the call back signal is lost after the call back signal arrives.

Although omitted in FIG. 7, for example, if it is determined in step S103 that a return signal has not been received, and if the return signal does not arrive within 10 seconds after the line is released, a timeout occurs and the process ends. In this case, it is possible to, for example, start again from the report.

Similarly, although omitted in FIG. 7, for example, if it is determined in step S106 that the phone is not off-hook, if the line is not captured within a certain time from the arrival of the return signal, the process ends as a timeout. Even in this case, it is possible to, for example, start the process again from the report.

In the above embodiment, when a reverse call signal arrives, the switching of the switching unit 1022 is performed by the retraction control unit 1012 under the control of the CPU unit 103, but this is not limited to the above. The CPU unit 103 may directly perform the switching of the switching unit 1022. Alternatively, the result of the determination from the reverse call signal determination unit 1011 may be supplied to the retraction control unit 1012, and the retraction control unit 1012 may independently switch the switching unit 1022 based on the result of the determination.

Furthermore, the functions of each of the line control unit 101 and telephone control unit 102 can be realized as functions of the CPU unit 103 by a program executed by the CPU of the CPU unit 103. That is, the functions of each of the return signal discrimination unit 1011, the pull-in control unit 1012, the answer/disconnect control unit 1013, and the notification control unit 1014 can also be realized by software. Similarly, the functions of each of the call control unit 1021, the switching unit 1022, and the hook state detection unit 1023 can also be realized by software.

In the above embodiment, after an emergency call, the switching unit 1022 is turned on when a call back signal arrives, and turned off when the incoming call back signal is interrupted (disappeared). However, this is not limited to this. For example, when a call back signal arrives and the telephone 2 is off-hook, the switching unit 1022 is turned on under the control of the hook state detection unit 1023 or the CPU unit 103. When the telephone 2 is on-hook, the switching unit 1022 is turned off under the control of the hook state detection unit 1023 or the CPU unit 103. Furthermore, when the incoming call back signal is interrupted (disappeared), even if the telephone 2 is off-hook, the retraction control unit 1012 turns off the switching unit 1022 under the control of the CPU unit 103. In this way, except when the incoming call back signal is interrupted (disappeared), the switching unit 1022 may be switched in conjunction with the hook state of the telephone 2.

[others]
As can be seen from the above description of the embodiment, the function of the claimed return signal discrimination means is realized by the return signal discrimination unit 1011 of the emergency notification device 1 of the embodiment. The function of the claimed switching means is realized by the switching unit 1022 of the emergency notification device 1 of the embodiment. Moreover, the function of the claimed retraction control means is realized by the retraction control unit 1012 of the emergency notification device 1 of the embodiment. Moreover, the claimed hook state detection means is realized by the hook state detection unit 1023 of the emergency notification device 1 of the embodiment. Moreover, the function of the claimed call control means is realized by the call control unit 1021 of the embodiment.

1... Emergency call device, 101... Line control unit, 1011... Return call signal discrimination unit, 1012... Lead-in control unit, 1013... Answer/disconnect control unit, 1014... Report control unit, 102... Telephone control unit, 1021... Call control unit, 1022... Switching unit, 1023... Hook state detection unit, 103... CPU unit, 104... Report button, 2... Telephone, 3... Gateway, 4... IP network, 5... Emergency call receiving agency

Claims (3)

An emergency call device that makes an emergency call to a predetermined emergency call receiving agency through an IP (Internet Protocol) network,
a callback signal discrimination means for discriminating whether or not a callback signal is transmitted in response to a callback operation at the emergency call receiving agency after the emergency call is made;
A switching means for switching between connection/disconnection between a telephone connected to the device and the IP network;
and a pull-in control means for switching the switching means to a non-connected state when a determination result in the reverse call signal determination means changes from the presence of the reverse call signal to its disappearance. 2. The emergency call device according to claim 1,
When the return signal determining means determines that the return signal is present, the retraction control means switches the switching means to a connected state. The emergency call device according to claim 1 or 2,
and a hook state detection means for detecting a hook state of the telephone set and controlling the switching means to switch to a non-connected state when the telephone set is in an on-hook state.

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