SU70222A1 - Device for switching subscriber lines in control room switches - Google Patents

Description

When using control switches with a central battery, such as an arrow type, there is a need to conduct circular or group calls with subscribers, for which the subscriber line sets of the switch must be connected to the General conversational buses. In this case, the DC circuits (the power supply current of the subscribers' microphones, as well as the ringing and burglar alarms) should not be interconnected so that their action is not disturbed and independent of the action of other subscribers.

At the same time, in order to reduce their own attenuation introduced by the switch circuit, subscriber line kits in their conversational part should not be permanently connected to all-split buses.

The listed requirements are met by the proposed device, which switches on subscriber lines in control switches with a central battery for

Beam subscriber switching system. In accordance with the invention, a telephone transformer is used for separating the DC circuits and all-talker wires, the primary winding of which is connected to the general talkers via the contact of a linear relay, into the secondary (linear) winding of which a capacitor is inserted, which prevents short-circuiting through this winding of a direct current .

The invention is illustrated in the drawing, which shows an electrical circuit of a linear subscriber set. The circuit consists of a transformer such as a telephone induction coil, a capacitor and a linear relay.

DC injection is supplied to the subscriber's line from the common-busbars through symmetrical half windings of the linear relay. The subscriber has a normal telephone set of the type of the Central Bank. Disconnection of a handset by a subscriber triggers a linear relay, the contacts of which close the ringing signal circuit and turn on175

The secondary winding of the transformer is connected to general branch buses.

In this way, subscriber lines are connected to commutator switching buses inductively and completely symmetrically, and the DC circuits of different lines do not depend on each other.

The proposed scheme also has the advantage that damage to one or several lines does not interrupt the operation of the entire switch. In addition, by appropriate selection of the capacitance of the capacitor and the self-induction of the transformer, it is possible to achieve an adjustment of the frequency response of the switch and create a large attenuation at a frequency of about 50-

100 Hz to reduce interference from electrified objects.

Subject invention

A device for switching subscriber lines in dispatching switches with a central battery for a beam subscriber switching system, characterized in that a telephone transformer, the primary winding of which is connected to common-branch coils via the contact of the linear relay, is applied to the secondary busbars (secondary linear) winding of which a capacitor is inserted, which prevents shorting through this: winding of a direct current circuit.

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Sc /

Linear

 Seen: Sator

K 8138

Signaling devices Nantopta