JPS6066551A - Telephone set having loud speaking receiver - Google Patents

Abstract

PURPOSE:To enable to switch from a loud speaking receiving circuit to a talking circuit using only the power source of a telephone circuit by restoring self-holding by a device that self holds the DC circuit of the telephone circuit and the off hook operation of a hand set, and at the same time, providing a combined hook switch switching the loud speaking receiving circuit and talking circuit. CONSTITUTION:When a non-lock switch for on hook transmission 21 is depressed, the anode and cathode of a thyristor 34 are conducted. The thyristor 34 self holds and supplies the DC to a dial circuit 4 and a loud speaking receiving circuit 6 and closes the circuit of the telephone circuit. When dialing is made by the dial circuit 4, A dial signal is sent out to the telephone circuit 1. When the handset is lifted after confirming the reply of a called person by a speaker, the contact 11 of a hook switch is operated, and the current between the anode and cathode of the thyristor 34 becomes off. However, the DC circuit is held by the off contact of the contact 11. At the same time, by the operation of interlocking contact 12, the loud speaking receiving circuit 6 becomes off, and the talking circuit becomes on, and the talking with the called person is changed to handset talking.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a telephone with loudspeaker reception, and more particularly to a switching circuit from a loudspeaker circuit to a speech circuit.

BACKGROUND ART Conventionally, this type of telephone with amplification system has a detection circuit that detects an off-hook operation of the handset during an on-hook call, and has the disadvantage that a separate power source other than the telephone line is required to operate the detection circuit. was there.

DISCLOSURE OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks and to provide a telephone with an amplification system that switches from an amplification circuit to a speech circuit using only the telephone line power supply. .

In order to achieve the above-mentioned object, the present invention includes a non-lock switch for on-hook dialing, a means for self-maintaining the direct current circuit of the telephone line by the communication current generated by turning on the switch, and a means for self-maintaining the direct current circuit of the telephone line by turning off the handset. In addition to restoring self-maintenance, this system employs a configuration that includes a hook switch that also serves as a switch between the receiving loudspeaker circuit and the speaking circuit.

Since the present invention is constructed as described above, it is possible to create a telephone set that automatically switches from the receiving loudspeaker circuit to the speaking circuit when the handset is turned off, using the power supply of the telephone line. be.

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of a telephone with loudspeaker receiving system according to an embodiment of the present invention, which includes a rectifier circuit 2 that determines the polarity of the DC circuit of a telephone line 1, and a non-lock switch 21 for on-hook transmission.
A DC closing circuit 3 that self-maintains the DC circuit of the telephone line 1 when 0 is turned on, a dialing circuit 4 and 5, a talking circuit 5, a loudspeaker circuit 6, and a hook switch that is linked to the handset as shown in the figure. It consists of contacts 11 and 12.
is the contact point of this hook switch.

FIG. 2 is a circuit diagram showing details of the DC connection circuit 3 shown in FIG. 1, and symbols A, B, and C marked with X indicate the same connection points as in FIG. 1, respectively.

Next, the operation will be explained with reference to FIGS. 1 and 2.

First, although not particularly shown in the figure, when the non-lock switch 21 for on-hook transmission is pressed in the on-hook state with the handset set, a DC current flows to the gate of the thyristor 34 through the resistor 31 and the resistor 33. The anode and cathode are electrically connected, and the thyristor 34 maintains itself and supplies direct current to the °C dial circuit 4 and the loudspeaker circuit 6, thereby closing the direct current circuit of the telephone line. Next, dial circuit 4
When dialing is performed, a dial signal is sent to the telephone line 1, and can be confirmed by the loudspeaker circuit 6 until the called party answers. In the case of a rotary dial, the capacitor 32 ensures self-retention of the thyristor 34 even if the DC circuit is interrupted during dial signal transmission.

Next, when the called person raises the handset after confirming it through the reception speaker, the off-hook operation of the handset activates the contact 11 of the hook switch, cutting off the current between the anode and cathode of the thyristor 34. Although the thyristor 34 is turned off, the DC circuit is maintained by the off contact of the contact 11. Due to the operation of the contacts 12 that operate simultaneously, the loudspeaker circuit 6 is turned off, the communication circuit 5 is turned on, and the communication power with the called party is 1.
/Switches to a set call.

As described above, according to the present invention, there is an effect that the loudspeaker circuit can be automatically switched to the handset communication circuit using only the power supply of the telephone line. J

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is an electric circuit diagram showing details of the DC connection circuit shown in FIG. 1.

Claims (1)

[Claims] a non-locking switch for on-hook transmission; a means for self-holding the direct current circuit of the telephone line by means of a talking current when the switch is turned on; and an off-hook operation of the handset to restore the self-holding, and to connect the receiving loudspeaker circuit and the talking circuit. What is claimed is: 1. A telephone with loudspeaker receiving and amplifying sound, characterized in that it is equipped with a hook switch that also serves as a switching function.