JPS61144155A - Telephone line connecting device - Google Patents

Abstract

PURPOSE:To connect easily a line system with a different form by installing a level impedance converting circuit between a telephone set main body of a terminal telephone set connected to different telephone line systems and a change-over switch which is installed between receivers. CONSTITUTION:Telephone line systems A and B are different telephone line systems, and a telephone set 3a, a receiver 4a, a telephone set 5b and a receiver 6b are connected to lines 1 and 2. When the line is connected, first, the line, which is desired to be connected beforehand by using the telephone set 3a and the telephone set 5b, is established respectively. The change-over switch is operated, and the sound signal line communicating to a receiver is mutually connected through a level impedance converting circuit. Thus, by using a signal line between a telephone set and a receiver, for which the difference by the system concerning connecting conditions is comparatively small, different lines can be comparatively connected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a telephone line connecting device, and particularly to a line connecting device that easily enables connection of different types of line systems.

[Conventional technology]

Conventionally, this type of connection device has been configured to directly connect a telephone line by interposing a signal conversion circuit.

[Problem that the invention seeks to solve]

The above-mentioned conventional connection devices are not suitable for signal conversion circuits or 2-4 wires, especially when the signaling systems or line formats (2-wire, 4-wire, etc.) are different between the two line systems to be connected. A line conversion circuit, etc. is required.

This not only makes the structure of the device complicated and expensive, but also makes it difficult to maintain the quality of the telephone line.

[Means for solving problems].

The telephone line connection device of the present invention includes terminal telephones for both line systems to be connected, a changeover switch interposed between the telephone body and the handset, and a simple level-impedance conversion circuit.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

Telephone line system A and telephone line system B are different telephone line systems, and include a telephone 3a, a receiver 4a, a telephone 5b, and a receiver 6.
Terminal telephones and receivers belonging to the respective telephone line systems are connected to lines 1 and 2.

When connecting lines, first, the lines to be connected are established in advance using the telephones 3a and 5b. After confirming that both lines are established,
By operating the changeover switch 7, the audio signal lines connected to each handset are connected to each other via a level/impedance conversion circuit 8. Further, since the changeover switch 7 is normally set in the direction of connecting the telephone and the handset, there is no problem in the normal operation of the telephone 3a and the telephone 5b.

〔Effect of the invention〕

As explained above, the present invention eliminates the need for complicated signal conversion circuits, etc., and improves transmission quality to a certain extent by using the signal line between the telephone and handset, which has relatively little difference in connection conditions depending on the system. It has an effect that can be secured relatively easily.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is a block diagram showing an embodiment of the present invention. 1, 2...Line, 2...Telephone line system B, 3a. 5b... Telephone, 4a, 6b... Receiver, 7... Selector switch, 8... Level/impedance conversion circuit.

Claims (1)

[Claims] It is characterized by having a switching switch interposed between the telephone body and the handset of terminal telephones connected to different telephone line systems, and a level-impedance conversion circuit provided between the switching switches. Telephone line connection equipment.