JP2674296B2 - Facsimile line switching device - Google Patents

Description

The present invention relates to a facsimile line switching device, and more particularly to a facsimile line switching device that switches information from a wired circuit or a wireless line for emergency communication and outputs the information to a standard facsimile device. Regarding

[Conventional technology]

In a facsimile switching device (hereinafter referred to as an adapter) added to a facsimile device (hereinafter referred to as FAX), communication is normally performed by a G3 procedure for a wired line, and in an emergency, the wireless line is switched to receive information from the center station. When the activation signal is input to the adapter from the wireless line via the wireless device, the wireless line and the facsimile device are forcibly connected, and the communication of the wired line is interrupted.

FIG. 2 is a block diagram of an example of a conventional facsimile line switching device. Normally connected to the wired line 19, FA
Facsimile communication by G3 is performed on the line (L1, L2) 2 of X1 via the line transformer 3, the hybrid circuit 4, the switching unit 5, the hybrid circuit 12 and the line transformer 13.

Upon receiving the emergency reception command from the center station, the wireless device 18 sends a start signal 15 to the control unit 14 of the adapter. The control unit 14 outputs the switching signal 20 to the switching unit 5 by the activation signal 15, and the switching unit 5 switches the line from the wired line 19 to the wireless device 18 by the switching signal 20 and disconnects the communication path between the FAX 1 and the wired circuit 19. To be done.

Fax 1 whose communication path has been cut off will immediately enter the standby state because the carrier will be disconnected during reception, but during transmission it will not enter the standby state during image signal transmission, and the fax of the other party's fax will be sent between pages of the transmitted document. Line 2 of FAX1 is released in response to an abnormal procedure,
The DC loop formed by the DC power supply 11 via the line transformer 3 is broken, and the detection circuit 9 outputs a loop break (OFF) to the control unit 14 by the loop detection signal 17. Control unit 14
Opens the loop of line 2 to transfer line 2 from FAX 1 to line transformer 3, hybrid circuit 4, switching unit 5, procedure exchange unit (converts standard G3 procedure and wireless one-way procedure) 6 line transformer for transmission 7, A communication path with the wireless device 18 is formed via the line transformer receiving unit 8, and communication information from the wireless device 18 is received with priority.

[Problems to be solved by the invention]

The conventional facsimile line switching device described above is a wireless device.
The call signal of FAX1 is forcibly cut off by the start signal from 18, and the standby state can be immediately set by the disconnection of the signal while receiving FAX1, but during the transmission, the page is sent and the communication procedure with the next page is performed. Since it cannot be put into a standby state until the operation is performed, there is a drawback that urgent information from the wireless line cannot be received immediately.

[Means for solving the problem]

The facsimile line switching device of the present invention is a facsimile line for connecting a facsimile device, which opens the line and stands by when the DC voltage of the line closed during communication is reversed, to a wired line or a wireless rotation from a wireless device. The switching device has means for inverting the polarity of the DC voltage in response to a start signal from the wireless device, and means for connecting the facsimile device to the wireless line when the polarity is inverted.

〔Example〕

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of one embodiment of the present invention.

In the present embodiment, when the DC power supply 11 of the line (L1, L2) 2 that is closed during communication reverses the polarity, the line 2 of L1, L2 is opened and the facsimile machine (FAX1) that is in the standby state is wired.
19 or the line switching operation to connect to the wireless line from the wireless device 18, the control unit 14 and the DC voltage reversing circuit 10 that reverse the polarity of the DC power supply 11 by the start signal 15 from the wireless device 18 to which the emergency command information is input. And, by reversing the polarity of line 2, FA
A DC loop detection circuit 9 that detects the line 1 in which X1 has opened the loop and outputs it as a DC loop detection signal 17, and a control unit 14 that connects the FAX 1 and the wireless device 18 to the line switching unit 5 by the DC loop detection signal 17 are provided. Configured to have.

 Next, the operation of this embodiment will be described.

Normally, FAX1 line (L1, L2) 2 is line transformer 3,
The hybrid circuit 4, the switching unit 5, the hybrid circuit 12, and the line transformer 13 are connected to the wired line 19 for communication.

Upon receiving the emergency command information, the wireless device 18 sends a start signal 15 to the control unit 14. The control unit 14 outputs the switching signal 20 to the line switching unit 5 by the activation signal 15 and simultaneously outputs the DC voltage inversion signal 16 to the DC voltage inversion circuit 10. The DC voltage inversion circuit 10 switches the polarity of the DC power supply (48V) 11 applied to the lines (L1, L2) 2.

By doing so, the transmitting FAX1 detects that the polarities of the lines L1 and L2 have changed and immediately stops the transmission operation, and can receive the information from the wireless device 18.

Note that the interruption during reception and the operation after the interruption are the same as those in the conventional example, and the description thereof will be omitted.

〔The invention's effect〕

As described above, according to the present invention, by providing the DC voltage application circuit having the function of reversing the polarity of the line of the facsimile device, the facsimile device which is transmitting on the wired line is quickly switched to the wireless line. The effect is that it can be received reliably.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of an example of a conventional facsimile line switching apparatus. 1 ... Facsimile, 2 ... Line (L1, L2), 3,7,8,1
3 ... Line transformer, 4 ... Hybrid circuit, 5 ...
… Line switching unit, 6… Procedure conversion unit, 9… DC loop detection circuit, 10… DC voltage inverting circuit, 11… DC voltage, 12
...... Hybrid circuit, 14 ...... Control section, 15 ...... Startup signal, 16 ...... DC voltage reversal signal, 17 ...... DC loop detection signal, 18 ...... Wireless machine, 19 ...... Wired line, 20 ...... Line switching signal.

Claims (1)

(57) [Claims] 1. A facsimile line switching device for connecting a facsimile device, which opens the line and stands by when the DC voltage of a line closed during communication reverses its polarity, to a wired line or a wireless line from a wireless device. A facsimile line switching device comprising: means for inverting the polarity of the DC voltage in response to a start signal from the wireless device; and means for connecting the facsimile device to the wireless line when the polarity is inverted.