JPS63117138U

JPS63117138U -

Info

Publication number: JPS63117138U
Application number: JP763487U
Authority: JP
Priority date: 1987-01-23
Filing date: 1987-01-23
Publication date: 1988-07-28

Description

[Brief explanation of drawings]

第１図はこの考案の一実施例による電話機を示
す回路図、第２図はその動作を説明するためのタ
イミングチヤート、第３図はこの考案の他の実施
例を示す回路図、第４図は従来の電話器を示す回
路図である。３はフツクスイツチ、４はマイクロホン、７は
受話器、２２は信号検出器、２３はタイマ、２５
は開放手段（開放スイツチ）。なお、図中、同一
符号は同一、又は相当部分を示す。 Fig. 1 is a circuit diagram showing a telephone according to one embodiment of this invention, Fig. 2 is a timing chart for explaining its operation, Fig. 3 is a circuit diagram showing another embodiment of this invention, Fig. 4 is a circuit diagram showing a conventional telephone. 3 is a switch, 4 is a microphone, 7 is a receiver, 22 is a signal detector, 23 is a timer, 25
is the opening means (opening switch). In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims

[Scope of utility model registration request]

In a telephone equipped with a switch, a microphone, a handset, etc., and a line is closed by a DC loop including the switch, a signal detector detects the presence or absence of audio and signals on the line in the closed state. A timer is provided in the DC loop, which is set when the signal detector detects that there is no voice or signal on the line, and is reset when it detects that there is voice or signal on the line. 1. A telephone set, characterized in that an opening means is arranged, and when the timer times out, the opening means cuts off the DC loop and opens the line.