JPS5880937A - Voice switch call device - Google Patents

Abstract

PURPOSE:To prevent breaks of a dial tone and a ringing tone during the calling of a called subscriber, by placing a loss control circuit in a call state on detecting an answer from the called subscriber due to the polarity inversion of a telephone circuit. CONSTITUTION:A voice switch call device has a transmission system 2 and a reception system 6 equipped with variable loss circuits 4 and 8, and a loss control circuit 9 controls the amounts of loss of the circuits 4 and 8 according to the difference in signal level between transmission and reception. A start control circuit 12 is interposed between the hybrid transformer 10 of said device and a telephone circuit 11. Terminals III and IV of the circuit 12 are connected to the circuit 11, and terminalsI and II are connected to the transformer 10. During origination or calling, the terminal IV is held at -48V and the terminal III is grounded; and a relay A is not in operation in said state and a contact 13 is broken to turn off the circuit 9, so that a dial or ringing tone is heard through an amplifier 7 and a speaker 5. When a called subscriber answers, the terminal III is held at -48V and the terminal IV is grounded and then the relay A is energized to make the contact. Consequently, the circuit 9 operates to allow normal mutual telephone service.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a voice switch communication device, and its purpose is to provide a voice switch that can be held in a receiving state by restricting the voice switch from operating until the called party answers. It is about providing.

Conventionally, as shown in Fig. 111, this type of device is equipped with a transmitting system (2) having a microphone (1), an amplifier (3), a variable loss circuit (audio switch) (4), and a speaker (1). 5)
An amplifier (υ) and a variable loss circuit (8
) is established.

The loss of the variable loss port h @ (4) and (8) is determined by the loss control circuit (9) depending on the difference between the transmitting signal level and the receiving signal level.
) is controlled by 01 is a hybrid transformer, which connects the variable loss circuits (4) (8) and the telephone line (b). When making a call without lifting the handset with a conventional telephone device configured in this way, if there is noise on the transmitting side and the dial tone when making a call and the ring tone during a call on the wt telephone line are low, the call may not be in the transmitting state. The outgoing tone and ringing tone from the hybrid transformer (2) are greatly affected by the sidetone of the transmitting signal, and are buried in the outgoing tone and ringing tone, and the dialing tone and ringing tone do not switch to receiving. There are drawbacks to call quality, such as interruptions or inaudibility.

Therefore, the present invention avoids the above-mentioned drawbacks by configuring the variable loss paths (4) and (8) to remain in the talking state until the called party answers. Example @
This will be explained based on FIGS. 2 and 8. Components having the same functions as those in FIG. 1 are given the same reference numerals and their explanations will be omitted.

(2) is the activation control path for detecting the polarity of the telephone line (b), and as shown in detail in Figure %1ilia, the terminal layer is connected to the terminal 1.1 connected to the hybrid transformer and the telephone line 6f). , W, and between terminal 1 and page, a series circuit of diode DI and resistor R1, a diode), relay A, and capacitor C are connected in parallel to the diode so that the polarity is reversed. The a contact (to) of relay A of $11 is connected to the loss control circuit (.).

With this configuration, the polarity of the telephone line (b) during outgoing and calling is set to terminal W, which is 14-volt, and the terminal layer to ground, so relay A is not excited in this state and is %a. Contact 1114 is in a broken state. Therefore, the loss control circuit (9) is instructed not to operate, and the outgoing tone and ringing tone from the telephone line (b) are from the telephone line (111m) - activation control circuit (2) -> vibe lift transformer 00 -> variable loss circuit body) -> receiving the call. It can be heard along the route (system (6) → amplifier (7) → speaker C).

When the called party answers during a call, the polarity of the vIt talk line is reversed, with terminal W at ground and terminal layer at 148 volts. As a result, relay A is energized and the off-lock of the loss control path (.) is released, resulting in normal alternate communication.

As explained above, according to the voice switch communication device of the present invention, the variable loss circuits are installed in the transmitting system and the receiving system, and the variable loss circuits are arranged in the transmitting system and the receiving system respectively, and the variable loss circuits are arranged so that the variable loss circuits are disposed in the transmitting system and the receiving system, and the variable loss circuits are arranged in the transmitting system and the receiving system, respectively, and the variable loss circuits are arranged in the transmitting system and the receiving system. A loss control circuit that controls the amount of loss in the circuit and an activation control circuit that detects the called party's response and switches the loss control circuit to the talking state are installed, so the dial tone when making a call and the sound that is heard while the called party is ringing are provided. If the call can be received without any interruption in the ringing tone, and if the configuration is configured such that the loss control circuit is controlled by determining the polarity of the IIE telephone line, it will not become complicated. be.

[Brief explanation of the drawing]

1lIIFI! J is a configuration diagram of a conventional voice switch communication device. The simplified diagram and FIG. 8 show an embodiment of the present invention, and Section 2(1)
- Microphone, (3) (7) - Amplifier, (4)
(8)...variable loss circuit, (5)-speaker, (9)
...loss control circuit, (tl-hybrid, todrance, (1-...telephone line, (2)...start-up control l path agent Yoshihiro Morimoto

Claims (1)

[Claims] 1. A variable loss circuit installed in each of the transmitting system and the receiving system, and controlling the amount of loss of the variable angle loss circuit according to the difference between the transmitting signal level, the receiving signal level, and O. A voice switch communication device comprising a loss control circuit and an activation control circuit for detecting a response of a called party and switching the loss control circuit to a talking state. i. The voice switch communication device according to claim 1, wherein the activation control circuit is configured to detect a response from the called party based on the polarity of the telephone line.