JPS60117948A - Automatic incoming call transfer device - Google Patents

Abstract

PURPOSE:To set automatically the input level of an amplifying circuit by detecting the signal level underwent the 2-wire/4-wire conversion and setting automatically the output of the amplifying circuit at a proper level. CONSTITUTION:When a call is started between both sides, the signals sent from a telephone circuit 1 are sent to a variable amplifying circuit 5 via a telephone circuit 2 and a 2-wire/4-wire converting circuit 3. The levels of these signals are detected by a level detection control circuit 4. This circuit 4 contains a comparator which compares the input signal level with a fixed detection level. Then the gain of the circuit 5 is reduced when the input signal level is higher than the fixed level and vice versa. Thus it is possible to set automatically the output signal of the circuit 5 at a proper level.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic call transfer device, and more particularly to an automatic call transfer device that detects the level of a 2-wire/4-wire converted signal and can dynamically set the input level of an amplifier circuit.

Conventionally, automatic call transfer devices for call signals do not have a function to measure the line loss up to the exchange. The purpose of the present invention is to detect the signal level converted from 2 wires and 4 wires, and to eliminate the above drawbacks. An object of the present invention is to provide an automatic call transfer device that can automatically set the input level of an amplification circuit according to the input level and eliminates the inconvenience when installing the device. A fourth telephone circuit that terminates the first telephone line that receives an incoming call, a second telephone circuit that terminates the second telephone line that makes the call, and the first and second telephone circuits are in a talking state. first and second switching means for converting these first and second telephone circuits into two-wire and four-wire circuits;

first and second amplification means that amplify the converted signals, respectively; first and second level detection controls that detect the converted signal levels and control input levels of the first and second amplification means; automatic dialing means for automatically sending a dialing signal of a preset telephone number to the second telephone line in response to a detection notification of a calling signal from the means;
and telephone line control means for monitoring and controlling the states of the first and second telephone lines.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a functional block diagram of an embodiment of an automatic call transfer device of the present invention. In the figure, 1 and 9 are PBX lines connected to the exchange or office line 2 is a telephone circuit that closes the telephone circuit of telephone line 1, 8 is a telephone circuit that closes the telephone circuit of telephone line 9, and 11 is a telephone A calling signal detection circuit detects the calling signal of line 1, 13 is an automatic dialing circuit that automatically dials a preset forwarding destination telephone number, and 12 is a telephone line that monitors the status of telephone circuits 2 and 8 and controls calls. Control circuit, 3 is a 2-wire 4-wire conversion circuit that converts the telephone circuit 202 wires to 4 wires, 7 is a 2-wire 4-wire conversion circuit that converts the 2 wires of the telephone circuit 8 to 4 wires, and 5 is a 2-wire 4-wire conversion circuit. A variable amplification circuit that amplifies the signal from circuit 3, 6 is a 2-wire 4-wire conversion circuit 7
A variable amplifier circuit 4 detects the signal level from the two-wire four-wire conversion circuit 3, and a level detection control circuit 10 controls the input level of the variable amplifier circuit 50 according to the detected level. is a level detection control circuit that detects the signal level from the 2-line and 4-line conversion circuit 7 and controls the output level of the variable amplifier circuit 6 based on the detected level.

When a ringing signal arrives at the telephone port Ml, the ringing signal is detected by the ringing signal detection circuit 11 via the telephone circuit 2, and the telephone circuit 2 detects the ringing signal by detecting the 0 ringing signal that closes the telephone line. The circuit 11 generates a control signal which activates the automatic dialing circuit 13 via the telephone line control circuit 12. Automatic dialing circuit 13 is telephone circuit 8
The communication circuit of the telephone line 9 is closed, and a preset transfer destination telephone number is automatically dialed. After the automatic dialing is completed, when the called party connected to the telephone line 9 answers, the response signal is detected by the telephone line control circuit 12 via the telephone circuit 8. The telephone line control circuit 12 has a telephone line 1°9 and a 2-wire 4-wire conversion circuit 3,
7 are connected respectively, and the telephone line 1 and the telephone line 9 are connected through the 2-wire and 4-wire conversion circuits 3 and 7 and the variable amplifier circuits 5 and 6.
Enables two-way communication with. When a two-way call is started, the signal from the telephone line 1 is sent to the variable amplifier circuit 5 via the telephone circuit 2 and the 2-wire/4-wire conversion circuit 3, and the signal level is detected by the level detection control circuit 4. Ru. This level detection control circuit has a comparator that compares the input signal level with a fixed detection level, and when the input signal level exceeds the detection level, the gain of the variable amplifier circuit is lowered and the input signal level is lower than the detection level. Sometimes, by increasing the gain of the variable amplifier circuit, the output signal level of the variable amplifier circuit 5 is automatically set to an appropriate level. The output signal of the variable amplifier circuit is sent to a telephone line 9 via a 2-wire/4-wire conversion circuit 7 and a telephone circuit 8. Also, the signal level from the telephone line 9 is the telephone circuit 8 and the 2-wire 411i! It is detected by the level detection control circuit 1o via the conversion circuit 17, and the input level p of the variable amplifier circuit 6 is automatically set to an appropriate level according to the detected level, and the 2-wire 4-wire conversion circuit 3 and the telephone circuit are connected. 2 to the telephone line 1. Note that the variable amplifier circuits 5 and 6 and the level detection circuits 4 and 10 may each have the same circuit configuration.

As explained above, according to the present invention, by detecting the signal level of the 2-wire 41IJ converted signal and automatically setting the output level of the amplifier circuit to an appropriate level,
You can achieve the effect of realizing an automatic call forwarding device that eliminates the need for level adjustment during installation.

[Brief explanation of drawings]

Claims (1)

[Claims] a first telephone circuit connected to a first necessary telephone line for incoming calls; a second telephone circuit connected to a second telephone line for originating calls; and the first and second telephone lines. first and second 2-wire/4-wire converting means for converting the first and second telephone circuits into 2-wire/4-wire when the circuits are in a talking state; and first and second 2-wire/4-wire converting means for amplifying the converted signals, respectively. a second amplifying means; first and second level detection control means for detecting the level of the converted signal and controlling output levels of the first and second amplifying means; a signal detecting means for detecting a calling signal to be sent to the second telephone line; and telephone line control means for monitoring and controlling the state of the second telephone line.