DE327159C - Signal circuit for telephone systems - Google Patents

Description

The invention relates to a signal circuit in connection with a telephone system, in which the existing cable routes are used for special signal outputs. Such Signals are, for example, fire reports, thief reports and the like Delivery of the messages can be provided at any point on the line, they can be manually movable or automatic devices.

To achieve this multiple use of the telephone system, the subscriber lines are led in the office via relays that either on the Switching device or act on the alarm device.

In the drawing is an embodiment of the invention in connection with a manually operated telephone system shown, all of which are irrelevant to the invention Parts are omitted.

The subscriber station Tl is through the lines α and b with the telephone exchange F.

25 ", where the lines end in jacks. If the subscriber wishes a connection, he removes his receiver from the hook, whereby a contact is closed and a current connection is established via the lines α and b , which energizes the call relay 22 in the office and thus causing the lighting of the call lamp AL. This has the entry of official and the execution of the connection in known manner to result.

A branch with a grounding contact Ta is now connected to the «-wire of the telephone line. If this contact is influenced, the following current flow occurs via the wires: earth, Ta, relay Fr, battery and earth. The relay Fr responds and closes the contact fr, whereby the signal system A comes into effect. The signal system can be designed differently depending on the purpose of the system, either just a simple alarm clock or one of the z. B. in fire alarm systems known receiving devices for the message.

The formation of the contact Ta and its inclusion in the line α can also be arbitrary. It can be arranged directly at the subscriber station as a button or at a distance from it, for example as a door contact or as a contact that is influenced by an automatic fire alarm, etc.

When establishing a connection as described above, the circuit arrangement shown also excites the relay Fr in addition to the call relay R , but its excitation is ineffective on the signal system because the opening of the normally closed contact r _{x of} the relay R causes the circuit of the signal system A is interrupted. Should the contact Ta be influenced after lifting the receiver on the subscriber part and the resulting closure of the line loop , the relay R will be short-circuited while the excitation of the relay Fr is maintained. This results in the signaling system being switched on in the manner described above.

The invention can be used not only with manually operated ferris intercoms, but

also use in automatic or semi-automatic systems. In such systems • could z. B. the 2? Relay in a telephone connection to let a preselector εη-run. The circuit of the relay Fr would remain the same as before, and so would its effect.

Claims (2)

Patent Claims: i. Signal switching in telephone systems, characterized in that the subscriber lines in the office run via relays, the conditions of excitation depending on their over the subscriber lines act either on the switching device or on the signaling device. 2. Signal circuit according to claim 1, characterized in that two relays are connected to the subscriber line in the office, one of which (22) dominates the switching and signaling device, while the other (Fr) acts only on the signaling device. 1 sheet of drawings.