JP2759970B2 - Call transfer device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention captures an incoming call from one station line connected to a device when the incoming call is received from the other station line, and the other station line also connected to the device. And a call transfer device for selecting a call partner to the central office on the call capturing side.

2. Description of the Related Art A conventional call transfer device is shown in FIG. Reference numeral 100 denotes a configuration diagram of the call transfer device, which includes the following parts.

Reference numeral 103 denotes a bell detection unit that detects a bell signal transmitted from the central office 114 through the central office line 115 and the capacitor 102 for blocking DC power. The detection output of the bell detection unit 103 is input to the control unit 101 and used for incoming call determination. 104
Is a relay for capturing the office line 114, which is controlled by the control unit 101 and forms / opens a DC loop with respect to the central office 114, and indicates the intention of calling, answering, or ending the call. 105 detects an instantaneous interruption of the DC loop current indicating an end of the call transmitted from the central office 114 via the office line 115 (hereinafter, this instantaneous interruption of the DC loop current is referred to as a CPC signal), and notifies the control unit 101 of the interruption. This is a CPC signal detection unit to perform. The capacitor 106 cuts off the direct current of the central office line 115 and transmits only the speech voice band signal to the internal speech path 120. On the other hand, a capacitor 107, a bell detection unit 108, a relay 109, C
The PC signal detection unit 110 and the capacitor 111 are respectively a capacitor 120, a bell detection unit 130, a relay 104, and a CPC signal detection unit 10.
5. The same operation as the capacitor 106 is performed. Internal communication path 120
Connects the capacitors 106 and 111
A signal connection between the telephone line 115 and the office line 116 is made in the voice communication band.

The telephone 112 is a telephone under the control of the central office 114, and is connected to the central office 114 via the central office line 113. Telephone 119, office line 1
18, the operation of the exchange 117, telephone 112, office line 113, exchange 1
Equivalent to 14.

FIG. 6 is a flowchart for explaining the operation of the conventional call transfer device 100 shown in FIG.

The operation will be described below with reference to the flowchart shown in FIG. In step 201, the bell 115
It is determined whether or not there is an incoming call. If there is no incoming call, the next step 202 is executed, and if there is an incoming call, step 203 is executed. In step 202, the bell detector 108 determines whether there is a bell incoming call on the local line 116. If there is no incoming call, the process returns to the first step 201, and the bell incoming monitoring of the local line 115 and the local line 116 is repeated. If the bell incoming is detected in step 202, the next step 204 is executed. In step 201, a bell call is detected on the line 115 in step 201, and step 20 is executed.
If you move to 3, the station line 116
It is determined whether or not the bell has arrived on the 116 side. When there is a bell incoming call on the office line 116, if both office lines are captured, an incoming collision will occur. Therefore, both office lines are not captured and the process returns to step 201 to monitor the incoming call on the office line 115 and the office line 116. If there is no bell incoming call on the office line 116, the process proceeds to the next step 205 because the call can be captured, the relays 104 and 109 are turned on, the incoming call is captured on the office line 115, and the outgoing call is captured on the office line 116. This state means that the caller can newly make a call from the telephone 112 to the office line 116 via the office line 113, the office exchange 114, and the office line 115. Central office exchange 117
The transmission operation to the telephone line 112, the office exchange 114, the office line 115, and the relay 1 is performed by the multi-frequency selection signal transmitted from the telephone 112.
04, condenser 106, internal communication path 124, condenser 111,
This is performed via the relay 109 and the office line 116. Here, the central office exchange 117 transmits a multi-frequency selection signal (hereinafter referred to as
This is called a DTMF signal. ) Is analyzed, and a bell signal is transmitted to the central office line 118 to which the telephone set 119 is connected, so that the telephone set 119 desired by the caller can be received. The call is established when the callee of the telephone 119 picks up the handset. The end of the call is determined by the caller of the telephone 112 or the callee of the telephone 119 returning the handset, and is connected to the call transfer device 100 from the central office (114 or 117) on the side where the handset is returned. A CPC signal is transmitted to both local lines (115 or 116). Steps 206 and 207 are performed for each local line (115 or 1).
16) This is the process of detecting the CPC signal by the CPC signal detector (105 or 110). Step 20 is performed until the CPC signal is detected.
6. Repeat step 207. If a CPC signal is detected in either of these steps, the process proceeds to step 208, where the relay
104 and 109 are turned off, the office line 115 and office line 116 are disconnected, and the call is terminated. After that, return to step 201, both stations line (156 and 116)
Resumes the bell incoming call monitoring.

By the way, the bell incoming monitoring of the office line 115 in the step 204 is the same as the processing in the step 203. If there is a bell incoming on the office line 115, the process returns to the step 201 to prevent the incoming collision, and the bell incoming monitoring is continued. Also, when the bell incoming call is not detected on the office line 115, the process proceeds to the step 205, the relays 104 and 109 are turned on, the incoming call is captured on the office line 116,
The station line 115 is transmitted and captured. The subsequent operation can be described in the same manner as in the case where the incoming call is captured on the station line 115 and the outgoing call is captured on the office line 116.

As described above, in the conventional call transfer device, a method is employed in which the DTMF signal transmitted from the caller's telephone is transmitted as it is to the call originating exchange via the call exchange and the call transfer device. I was

SUMMARY OF THE INVENTION However, in such a call transfer device, when the central office on the side of capturing and receiving a call receives a pulse dial signal as a selection signal, the DTMF transmitted from the caller is used.
No new transmission was possible on the originating station line with the signal.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the present invention provides a tone signal receiving means for receiving a tone signal, and a pulse signal for transmitting a pulse signal corresponding to the signal received by the tone signal receiving means. And transmitting means for connecting the tone signal receiving means to the called station line, and then capturing the calling station line to obtain the pulse signal transmitting means. Is output to the calling-side curve, and when it is detected that a signal indicating the end of the call has arrived from the first station line, the control for disconnecting the tone signal receiving means from the called-side station line is performed. Is performed.

According to the present invention, even if the central office at the place where the call transfer device is installed accepts only pulse signals, the present invention is connected to the telephone set of the caller, that is, to the called line. As long as there is only a means capable of sending a tone signal to the telephone set, the pulse signal can be sent to the local exchange on the calling side.

Also, when a signal indicating the end of the call, such as a CPC signal, is sent from the called station line, the tone signal receiving means is disconnected so that, for example, an incoming call is sent to the called station line. Yes, tone line receiving means is not required if the line is cut off due to some kind of trouble, or if the caller mistakenly enters the telephone number to be called and cuts off the line. In this state, the tone signal receiving means is immediately disconnected from the called line.

Embodiment An embodiment of a call transfer device according to the present invention will be described below with reference to FIGS. 1, 2, 3, and 4. FIG.

FIG. 1 is a block diagram of a call transfer device according to the present invention.
Is a call transfer device main body.

Reference numeral 303 denotes a bell detection unit which detects a bell signal transmitted from the central office exchange 314 through the central office line 315 and a capacitor 302 for blocking DC power. The detection output of the bell detection unit 303 is input to the control unit 301 and used for incoming call determination. 304
Is a relay for capturing the office line 315, which is controlled by the control unit 301 and forms / opens a DC loop with respect to the central office exchange 314, and indicates the intention of answering or terminating the call, and transmits and captures the office line. When the DC loop is interrupted, the pulse dial signal is transmitted. 305 detects a CPC signal transmitted from the central office exchange 314 via the office line 315 and notifies the control unit 301
This is a CPC signal detection unit. The capacitor 306 cuts off the direct current of the local line 315, and operates between the contact c of the local line 315 and the relay 320 and the contact 321 of the resistor 321 and the contact a of the relay 322, which function to attenuate the voice voice band signal. It is for communication. On the other hand, a capacitor 307, a bell detector 308, a relay 309, and a CPC signal detector 310 connected to the central office 317 through the office line 316 respectively include a capacitor 302 and a bell detector 30.
3. Performs the same function as the relay 304 and the CPC signal detection unit 305.
The capacitor 311 cuts off the direct current of the local line 316 and
And contact 320 of relay 320, contact b of resistor 321 and relay 322
This is for transmitting only the speech voice band signal to and from. The relay 320 is connected to both ends of the resistor 321 and short-circuits both ends of the resistor 321 during a call between the two office lines (315 and 316) to prevent attenuation of the signal level of the speech sound band. Also,
It is turned off during pulse dial transmission to the calling station line, and the function of the resistor 321 causes the calling station line (when the station line 315 is the receiving station line, the calling station line becomes the station line 316, and vice versa). Yes.) Reduce the intermittent sound of the pulse dial signal leaking to the destination line. DTMF signal receiver 323 is relay 3
22 and is switched to the contact a or the contact b under the control of the control unit 301.
When a DTMF signal arriving from 5 is received and connected to the contact b, a DTMF signal arriving from the station line 316 is received, and the received data is input to the control unit 301. Also, during reception of the DTMF signal from the incoming capture side curve, the relay 320 is turned off, and the DTMF signal coming from the incoming capture side office line is protected from the interruption of the DC loop current intermittent sound of the pulse dial signal sent to the outgoing capture side curve. I do. 324, a storage unit connected to the control unit 310, a buffer BF for storing the DTMF signal data received by the DTMF signal receiving unit 323, a program area PA storing a control program according to the flowchart of FIG. It has a table area storing the conversion table shown in FIG. The necessity of the buffer BF in the storage unit 324 is based on the fact that the reception DTMF signal 500 is converted into the transmission pulse dial signal 501 as shown in FIG. In the case of a pulse transmission speed of 10 PPS, it takes 1 second to transmit 10 pulses.) That is, the received high-speed DTMF signal data is buffered one after another in the buffer BF in the storage unit 324, and is sequentially converted into a low-speed pulse dial signal according to the conversion table TB in FIG. Sent to the line. Receive DTMF signal
As shown in FIG. 3, the conversion rule for 500 pulse dial signals is that a DTMF signal meaning 0 is converted to a 10-pulse pulse dial signal, and a DTMF signal meaning * and 無 し means that no pulse is sent. It is discarded without being buffered in the buffer BF in 324.

The telephone 312 is a telephone under the control of the central office 314 and is connected to the central office 314 via a central office 313. Telephone 319, office line 3
18, exchange 317 works, telephone 312, office line 313, exchange 3
Equivalent to 14.

FIG. 2 is a flow chart showing the operation of the call transfer apparatus of the present invention. In step 401, it is determined whether or not a bell is received on the office line 315 based on the input of the bell detecting unit 303. Execute 402, step 403 if any
Execute In step 402, it is determined whether or not there is a bell incoming call on the local line 316 based on the input of the bell detecting unit 308.
Repeat the bell incoming monitoring. If a bell incoming call is detected in step 402, the next step 404 is executed. In step 401, a bell incoming call is detected on the office line 315 in step 401, and when the process proceeds to step 403, it is determined whether or not a bell incoming call is present on the office line 316 in order to capture the outgoing call on the office line 316 side. I do. If there is a bell incoming call on the office line 316, if it is captured as it is, an incoming collision between the office line 315 and the office line 316 occurs, so step 40
It returns to 1 and monitors the bell incoming of the office line 315 and the office line 316. If there is no bell call on the office line 316, since the office line 316 can be transmitted and captured, the process proceeds to the next step 406 and the relay 322 is set to the contact a.
And the DTMF receiving unit 323 is connected to the receiving-side office line 315. Next, in step 407, the relay 304 is turned on, the incoming call is captured on the office line 315, the relay 309 is turned on, and the outgoing call is captured on the office line 316.
In step 408, the relay 320 is turned on, the resistor 321 is short-circuited, and the dial tone transmitted from the central office 317 through the central office line 316 is set to be audible on the telephone 312 of the caller. In step 409, the DTMF signal receiving unit 323 determines whether or not a DTMF signal has been received, and if not, proceeds to step 418. Step 418 and step 419
Then, the CPC signals of both the local lines (315 and 316) are monitored as already described in steps 206 and 207 of FIG. If no CPC signal is received in both steps (418 and 419),
Returning to step 409, the processing of steps 409, 418, and 419 is repeated until a DTMF signal is received or a CPC signal is received from one of the local lines (315 or 316).
If a CPC signal is detected in step 418 or step 419, the process proceeds to step 420, where both relays 304 and 309 are turned off, both office lines (315 or 316) are disconnected, and the call is terminated. After that, return to step 401,
Resume 316 incoming call detection.

When the DTMF signal is received in step 409, the process proceeds to the next step 410, the relay 320 is turned off, and the calling station line 3
Incoming station line 315 for sending pulse dial signal to 16
To mute. Next, in step 411, the DTMF
It is determined whether or not the signal reception has been completed. If the reception has been completed, the process proceeds to the next step 412, and the storage unit 324 buffers the received one-digit DTMF signal dial data. In the next step 413, it is determined whether or not the one-digit pulse dial transmission sequence has been completed, and if it has been completed, the process proceeds to step 414, where the transmission dial data of the transmission dial data is transmitted from the storage unit 324 to transmit the pulse dial signal. Perform reading. If the pulse dial transmission sequence is currently being executed, the process directly proceeds from step 413 to step 415, and the sequence following the currently executed pulse dial transmission sequence is executed. In step 415, the local line 316 output waveform 62
As shown at 0, the office line 316 is turned ON (623) and OFF (62
4) is performed, and a dial pulse transmission sequence 622 and an interdigit pause transmission sequence 625 are executed. When a part of these sequences is executed, the process exits from step 416 and returns to step 411. If the DTMF signal is still being received in step 411, the process proceeds to step 416, and it is determined whether or not reading of all dial data in the storage unit 324 has been completed.
If there is still dial data in the storage unit 324, the flow shifts to step 413 to determine whether or not the one-digit pulse dial transmission sequence has already been completed. If the reading of all dial data in the storage unit 324 has been completed in step 416, the process proceeds to step 417, where it is determined whether or not the one-digit pulse dial transmission sequence has been completed. If the transmission sequence is being executed, the flow shifts to step 415 to continue the pulse dial transmission sequence. Step 417
If the pulse dial transmission sequence has been completed at
Returning to step 408, the relay 320 is turned on again, and the subsequent steps 409, 418, and 419 are repeated, and DTMF signal reception monitoring and CPC detection of both office lines (315 and 316) are performed.

If it is determined in step 402 that a bell incoming call is detected on the local line 316, the process proceeds to step 404, and bell incoming monitoring of the local line 315 is performed. If a bell incoming call is detected, the process returns to step 401 to continue bell monitoring for both office lines in order to prevent an incoming collision between both office lines. However, if a bell call is not detected on the line 315, the process proceeds to step 405 and the relay 322 is set to the contact b.
DTMF signal receiving unit 323 is connected to the local line 316 on the receiving side, and the DTMF signal receiving unit 323 is set to a state where it can receive the DTMF signal. From the next step 407 onward, the description can be made in the opposite situation where the above-described office line 315 is the receiving office line and the office line 316 is the calling office line.

Here, a description will be given of the timing chart of the transmission pulse dial signal conversion of the received DTMF signal in FIG. 4 with the incoming call capturing side office line as office line 315 and the outgoing capture side office line as office line 316.

a) is a signal waveform on the local line 315, which is curved from the telephone 312.
313 shows a DTMF signal transmitted via the central office 314. Note that the internal numerical values indicate dial data.
FIG. 4B is a diagram showing buffering data of the buffer BF in the storage unit 324, in which dial data is not yet buffered, DTMF signal is buffered in step 411, and all buffering data is stored. Indicates a state where transmission has been completed. c) shows the operation of the relay 320. The relay 320 is turned on in step 408, and when the DTMF signal is received, the relay 320 is turned off in step 410. After that, all the buffering data stored in the buffer BF in the storage unit 324 is transmitted, and at the timing when the pulse dial signal transmission sequence ends, the process proceeds from step 417 to step 408, the relay 320 is turned on, and then at step 409 It remains ON until a DTMF signal is received. d) is an output waveform to the central office line 316. In step 414, one digit of dial data is read from the storage unit 324, and in step 415, a sequential dial pulse transmission sequence is executed, followed by interdigit pause transmission. Execute sequence I. Next, the storage unit 32
The dial data is read out from 4, and the transmission of a pulse dial signal meaning dial "1" is started. When the entire transmission sequence of the dial “1” is completed, the storage unit 32
The dial data is read out from 4, and a pulse dial signal transmission sequence meaning dial "2" is started.

As described above, when the station line on the called side is captured as in the present embodiment, the tone signal coming from this station line is received, and the signal is converted into a pulse signal. If the user who made a call to the called line has a telephone set that outputs a tone signal, the central office connected to the calling line will send a pulse. Even when only the signal is supported, the call can be transferred.

In general, a call transfer device is often composed of a large number of office lines, and all the office lines have a DTMF signal receiving unit 323.
Rather than providing the DTMF signal receiving unit 323 only when the DTMF signal is transmitted, the DTMF signal receiving unit 3
23 can be shared, the number of DTMF signal receiving units 323 can be reduced, and the cost can be reduced. Therefore, as in the present embodiment, the CPC
If a signal indicating the end of the call, such as a signal, is sent, DT
By disconnecting the MF signal receiving unit 323, for example, there is an incoming call on the called line, and then the line is disconnected due to some kind of failure, or a telephone number to call the caller When the DTMF signal receiving unit 323 is not needed, such as when the user accidentally inputs a line and disconnects the line, the DTMF signal receiving unit 323 is immediately disconnected from the called line. As mentioned above, the DTMF signal receiver
323 can be shared.

Further, when the CPC signal of the CPC signal detector of one station line is detected, the relay of the called station line is turned off, and in addition to opening this station line, the relay of the other station line is also turned off. In addition, this line is also released, so that when one of the calls is terminated, both lines will be released promptly, the time for which the line is connected will be shortened, and telephone charges will be reduced. Can be reduced, and this office line can be used for other transfer operations, so that the office line can be effectively used.

By the way, since the DTMF signal indicates dial data by a combination of specific frequencies, it is possible to identify any dial data in almost the same time, and the identification time is instantaneous. On the other hand, the pulse signal indicates the dial by counting the number of pulses transmitted at a predetermined interval (usually 1/10 to 1/5 second intervals).
Number "0" in the pulse signal that sends a pulse in 10 seconds
It would take about 0.9 seconds to send out. In Japan, the dial data for one telephone number is usually 10 digits (assuming that it is input from the area code), so it takes about 9 seconds at worst.

Therefore, one after another before the output of this pulse signal ends.
The situation where the DTMF signal is output occurs, and the DTMF signal is output.
If the dial data received by the MF signal is directly converted into a pulse signal, the pulse signal cannot be accurately converted. In order to prevent this, the caller needs to confirm that the pulse signal is terminated each time a one-digit dial signal is input.

Therefore, the DTM received by the DTMF receiving unit 323 as in the present embodiment is
By buffering the dial data of the F signal in the storage unit 324 and calling up the buffered dial data to generate a pulse signal, the caller successively inputs the dial data with the DTMF signal. Even the storage unit 32
4 is buffering these data and transmitting a pulse signal while referring to the buffered dial data, so that the user does not need to worry about whether the pulse signal has ended or not, It is possible to accurately transmit a telephone number by a pulse signal.

According to the present invention, a tone signal receiving means for receiving a tone signal, and a pulse signal sending means for sending a pulse signal according to the signal received by the tone signal receiving means are provided to capture a line on the called side. In this case, the tone signal receiving means is connected to the called line, and thereafter, the calling line is captured, and the output of the pulse signal transmitting means is output to the calling line. Further, when it is detected that a signal indicating the end of the call arrives from the called line, the tone signal receiving means is controlled to be disconnected from the called line. Therefore, even if the central office at the place where the call transfer device is installed is an exchange that accepts only pulse signals, as long as there is a means that can send a tone signal to the caller's telephone, it can be used as an exchange on the calling line. Sending a pulse signal As much as possible, call transfer by the present call transfer device can be performed even in an area where a central office that accepts only such pulse signals is installed.

In general, a call transfer device is often composed of a large number of office lines, and rather than providing tone signal receiving means for all the office lines, the tone signal is transmitted only when the tone signal is transmitted by the above-described transfer. If the receiving means is connected, it becomes possible to use the tone signal receiving means also as another station line, so that the number of tone signal receiving means can be reduced and the cost can be reduced. Therefore, as in the present invention, when a signal indicating the end of a call, such as a CPC signal, is transmitted from the called station line, the tone signal receiving means is disconnected, for example, An incoming call is received on an office line, and then the office line is disconnected due to some kind of failure, or the caller incorrectly enters the telephone number to call,
If the tone signal receiving means is no longer needed, such as when the line is cut off, the tone signal receiving means and the called station line are immediately disconnected, and as described above, a plurality of station lines are disconnected. Thus, the tone signal receiving means can also be used.

[Brief description of the drawings]

FIG. 1 is a block diagram of a call transfer device according to an embodiment of the present invention, FIG. 2 is a flowchart showing a control procedure in the call transfer device according to the present invention, and FIG. 3 converts a received DTMF signal into a transmission pulse dial signal. A diagram showing a conversion table,
FIG. 4 is a timing chart of the transmission pulse dial signal conversion of the received DTMF signal in the call transfer device according to the present invention, FIG. 5 is a configuration diagram of the conventional call transfer device, and FIG. 6 shows the processing in the conventional call transfer device. It is a flowchart. 112,312 Telephone 113,313 Telephone 115,315 Telephone 116,316 Telephone 118,318 Telephone 119,319 Telephone

Claims (3)

(57) [Claims] 1. A first terminal and a second terminal connected to different office lines, respectively, first acquisition means for acquiring / opening an office line connected to the first terminal, and Second capturing means for capturing and releasing the office line connected to the second terminal, tone signal receiving means for receiving a tone signal, and a pulse signal for transmitting a pulse signal according to the reception of the tone signal receiving means. Sending means, an end signal detecting unit for detecting a signal indicating an end call coming from the first terminal, an incoming call is generated at the first terminal, and When the station line connected to the terminal 1 is captured,
The tone signal receiving means is connected to the first terminal, and thereafter, the second capturing means captures the office line connected to the second terminal. Control means for performing control to send a pulse signal to a terminal, the control means further comprising: when the end signal detection unit detects a signal indicating end of the call, the tone signal receiving means and the first terminal. A call transfer device characterized by performing control for separating the call from the caller. 2. A first terminal and a second terminal respectively connected to different office lines, a first acquisition unit for acquiring and releasing an office line connected to the first terminal, and Second capturing means for capturing and releasing the office line connected to the second terminal, tone signal receiving means for receiving a tone signal, and a pulse signal for transmitting a pulse signal according to the reception of the tone signal receiving means. Sending means, an end signal detecting unit for detecting a signal indicating an end call coming from the first terminal, an incoming call is generated at the first terminal, and When the station line connected to the terminal 1 is captured,
The tone signal receiving means is connected to the first terminal, and thereafter, the second capturing means captures the office line connected to the second terminal. And control means for performing control for transmitting a pulse signal to a terminal. The control means further comprises a station connected to the first terminal when the end signal detection unit detects a signal indicating end of call. A call transfer device for performing control for releasing a line and a central office line connected to the second terminal. 3. A first terminal and a second terminal connected to different office lines, respectively, first acquisition means for acquiring / opening the office line connected to the first terminal, and Second capturing means for capturing and releasing the office line connected to the second terminal, tone signal receiving means for receiving a tone signal, and buffering dial data indicated by the tone signal received by the tone signal receiving means. A pulse signal transmitting means for transmitting a pulse signal corresponding to the dial data stored in the storing means; and causing the first capturing means to capture the office line connected to the first terminal. In this case, the tone signal receiving means is connected to the first
, And then controls the second capturing means to capture the local line connected to the second terminal, and causes the pulse signal transmitting means to transmit the pulse signal to the second terminal. And a control unit for performing a call.