KR100208387B1 - Enlargement line control circuit for facsimile - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs

A facsimile line interface circuit having an extension telephone, which relates to a circuit for controlling the connection of an extension telephone line to a telephone line.

I. The technical problem to be solved by the invention

It does not use separate relay and provides extension telephone line control circuit that can control connection of extension telephone line at all times.

All. Summary of Solution of the Invention

A first hook switch that connects the ringer circuit to the telephone connection line when the handset is in a hook-on state and a hook hook that interlocks with the first hook switch and disconnects the ringer circuit from the telephone connection line when the handset is in a hook-off state; And a second hook switch for connecting the extension telephone line to the telephone connection line and disconnecting the extension telephone line from the telephone connection line when the handset is hooked off.

la. Important uses of the invention

It is used for the facsimile equipped with the extension telephone.

Description

Facsimile extension telephone line control circuit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile having an extension telephone, and more particularly to a circuit for controlling the connection of an extension line to a telephone line in a line interface circuit.

The facsimile typically includes a line interface circuit called a Line Interface Unit (LIU) or a Network Control Unit (NCU). The line interface circuit is connected to a telephone line of a telephone network such as a public switched telephone network (PSTN) to provide an interface. This line interface circuit operates in telephone mode or facsimile mode. The telephone mode is a mode for receiving a ring signal or using an extension telephone or a handset, and the facsimile mode is a mode for facsimile transmission and reception. Normally, the phone enters the telephone mode while the fax is in a standby state, and switches to the fax mode when the fax is transmitted or received.

The extension telephone is a telephone which is connected to the facsimile from an external device separately from the handset mounted on the facsimile, and when the extension telephone is used to connect to the facsimile, it can make or receive a call even when a power failure occurs. Such extension telephones are used in connection with extension telephone lines installed in the facsimile line interface circuits for which extension telephones can be used. Thus, the facsimile having the extension telephone controls the connection of the extension telephone line to the telephone line according to the operating state. That is, in standby, the extension telephone line is connected to the telephone line, and the extension telephone line is blocked for the telephone line when making or receiving a fax transmission or reception or making a telephone call using the handset mounted in the fax.

FIG. 1 shows a typical line interface circuit having a circuit for controlling an extension telephone line. Referring to FIG. 1, the relay 100 uses a pair of modem connection lines under the control of a control unit (not shown) of a telephone line T and R formed of a tip and a ring line. (200, 202) and a pair of telephone connection lines (204, 206). A modem (modulator-demodulator) 104 is connected to the modem connection lines 200 and 202 through a transformer 102. The modem 104 modulates the facsimile transmission signal and transmits it to the telephone line, or demodulates the received signal from the telephone line and provides it to the control unit of the facsimile.

A pair of extension telephone lines L1 and L2 to which telephone extension lines (not shown) are connected to the telephone connection lines 204 and 206 are connected via a relay 116, and a ring detector 106 and a remote controller are connected. The remote circuit 108 is directly connected, and the ringer circuit 112 and the handset communication circuit 114 are connected via a hook switch 110. The ring detector 106 detects the ring signal received from the telephone line and informs the control unit of the fax. The remote circuit 108 provides an interface for remote control. The hook switch 110 is mechanically hooked on or hooked off by a handset (not shown). The hook switch 110 connects the telephone connection lines 204 and 206 to the ringer circuit 112 in the hook on state and the telephone connection line in the hook off state. 204, 206 to handset communication circuit 114. The ringer circuit 112 is used to generate a bell signal when a ring signal is received from the telephone line T and R in a power failure state, and the handset communication circuit 114 provides a call by the handset. The relay 116 is turned on / off by the control unit of the facsimile to connect or disconnect the extension telephone lines L1 and L2 to the telephone connection lines 204 and 206.

In the line interface circuit as described above, the relay 100 is switched to the telephone mode or the facsimile mode by the control unit of the facsimile. That is, when the fax is in the standby state, the relay 100 enters the telephone mode and connects the telephone line T and R to the telephone line 204,206. Accordingly, it is possible to receive a ring signal from the telephone line T or R or to use an extension telephone or handset. At this time, the relay 116 is turned on, and the extension telephone lines L1 and L2 are connected to the telephone connection lines 204 and 206. The relay 116 is turned off when fax transmission and reception are performed or the handset is used. , L2) is disconnected. The hook switch 110 connects the ringer circuit 112 to the telephone connection lines 204 and 206 in a hook-on state, and when the handset is hooked off, the handset communication circuit 114 is connected to the telephone connection line instead of the ringer circuit 112. (204, 206). When the facsimile is used in this state, the relay 100 switches to the fax mode by the control unit of the facsimile and connects the telephone line T and R to the modem connection lines 200 and 202. Accordingly, facsimile transmission and reception using the modem 104 can be performed.

As described above, the connection of the extension telephone lines L1 and L2 to the telephone connection lines 204 and 206 connected to the telephone line T and R in the standby state was controlled using a separate relay 116. In this case, since the relay 116 is controlled by a control unit of the facsimile, a control port of a central processing unit (CPU) used as a control unit is required. In addition, when the power failure or the power of the facsimile is turned off, the control unit of the facsimile does not operate so that the control of the relay 116 is impossible. In this case, the extension telephone may bridge with the handset mounted in the facsimile.

As described above, there is a problem in that, in addition to the need for a separate control port as well as control of the connection of the extension telephone line using a relay, control is impossible when a power failure or the power of the facsimile is turned off. In addition, there is a disadvantage in that the cost of the product is increased due to the separate use of a bulky relay.

It is therefore an object of the present invention to provide an extension telephone line control circuit that can control the connection of an extension telephone line at all times without using a separate relay.

1 is a line interface circuit diagram of a conventional facsimile;

2 is a line interface circuit including an extension telephone line control circuit according to an embodiment of the present invention.

The present invention for achieving the above object is a first hook switch for connecting the ringer circuit to the telephone connection line when the handset is in the hook-on state and the ringer circuit is disconnected from the telephone connection line when the handset is in the hook-off state; And a second hook switch that interlocks with the hook switch and connects the extension telephone line to the telephone connection line when the handset is in the hook-on state and disconnects the extension telephone line from the telephone connection line when the handset is in the hook-off state. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the annexed drawings, numerous specific details are set forth in order to provide a thorough understanding of the present invention, such as specific circuit configurations or components. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

Figure 2 shows a line interface circuit diagram including an extension telephone line control circuit according to an embodiment of the present invention, the first to be interlocked instead of the hook switch 110 in addition to removing the relay 116 in the circuit of FIG. The second hook switches 116 and 118 are configured. And additionally install a jumper (jumper 120). Therefore, the remaining portions except for the first and second hook switches 116 and 118 and the jumper 120 are the same as in FIG. 1.

In FIG. 2, the first hook switch 116 is connected between the telephone connection line 204 and the ringer circuit 112. The first hook switch 116 is turned on / off according to the hook state of the handset to connect the ringer circuit 112 to the telephone connection lines 204 and 206 when the handset is in the hook-on state and the ringer circuit when the handset is in the hook-off state. Block 112 from telephone connection lines 204 and 206. The second hook switch 118 is connected between the telephone connection lines 204 and 206, the handset communication circuit 114, and the extension telephone lines L1 and L2. The second hook switch 118 is interlocked with the first hook switch 116 according to the hook state of the handset, and connects the extension telephone lines L1 and L2 to the telephone connection lines 204 and 206 when the handset is in the hook-on state. The extension telephone lines L1 and L2 are disconnected from the telephone connection lines 204 and 206 when the handset is hooked off. In addition, the jumper 120 is installed between the telephone connection line 204 and the extension telephone line (L2).

In the above state, switching between the telephone mode and the facsimile mode by the relay 100 is the same as in FIG. 1 described above. The first hook switch 116 is turned on while the handset is in the hook-on state. In this state, when the fax is in the standby state, since the telephone connection lines 204 and 206 are connected to the telephone line T and R, the ringer circuit 112 is connected. Is connected to the telephone line (T, R). At this time, the second hook switch 118 connects the extension telephone lines L1 and L2 to the telephone connection lines 204 and 206. Accordingly, it is possible to receive a ring signal from the telephone line T or R or to use an extension telephone. When the handset is used in this state, the first hook switch 116 is turned off so that the ringer circuit 112 is disconnected from the telephone connection lines 204 and 206. The second hook switch 118 cuts off the extension telephone lines L1 and L2 which were connected to the telephone connection lines 204 and 206 and connects the handset communication circuit 114. This enables handset calls.

Therefore, unlike the related art, by additionally controlling the extension telephone line by a hook switch without using a separate relay, the extension telephone line can always be controlled even when power is normally supplied, even when a power failure or power is turned off.

In addition, the jumper 120 is intended to meet national standards, and when used in a country where the bridge is not allowed, the jumper 120 is opened and the jumper 120 is inserted in the country where the bridge is allowed. As a result, all national standards can be met.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications can be made without departing from the scope of the present invention. In particular, in the embodiment of the present invention has been shown an example of installing the jumper 120, it is shown that it can be used additionally, it is not necessary to use if not necessary. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the equivalents of the claims and the claims.

As described above, the present invention can control the extension telephone line by controlling the extension telephone line by the hook switch, so that even if a power failure or the power is turned off, the cost of the product can be lowered because there is no need to use a separate relay and control port. There is an advantage.

Claims (2)

In the extended telephone line control circuit of the facsimile that controls the connection of the extension telephone line to the telephone line connected to the telephone line in the standby state, A first hook switch for connecting a ringer circuit to the telephone connection line when the handset is in a hook-on state and for disconnecting the ringer circuit from the telephone connection line when the handset is in a hook-off state; A second interworking with the first hook switch and connecting the extension telephone line to the telephone connection line when the handset is in the hook-on state and blocking the extension telephone line from the telephone connection line when the handset is in the hook-off state; An extension telephone line control circuit comprising a hook switch. 2. The extension telephone line control circuit according to claim 1, further comprising a jumper provided between the telephone connection line and the extension telephone line.

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