JPH0343823B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a doorway slave unit for an intercom, and more particularly to a doorway slave unit for an intercom system equipped with a plurality of indoor units, such as in a two-family house.

[Prior Art] As shown in FIG. 4, a conventional intercom system for a two-family house has two entrance slave units 2 corresponding to the indoor unit 11 of household A and the indoor unit 12 of household B.
Generally, 01 and 202 are installed side by side at the entrance, and in this system, a customer from household A makes a call using the entrance handset 201 - indoor unit 11, and calls from household B.
The customer made a call using the entrance handset 202 and the indoor unit 12, and each system was independent.

[Problems to be Solved by the Invention] As described above, in the conventional intercom system for two-family residences, two entrance cordless units are installed side by side at the entrance, which makes the entrance look unattractive, and also makes it difficult to configure the equipment. There was a problem in that it required the cost of two machines and also increased the installation cost. The present invention
It is an object of the present invention to reduce installation costs and system costs by using a single entrance slave unit in an intercom system equipped with a plurality of indoor units such as in a two-family house.

[Means for Solving the Problems] In order to achieve such an object, the entrance handset of the present invention includes a communication circuit, a latching relay for connecting the communication circuit to one of a plurality of base units, and a latching relay for connecting the communication circuit to one of the base units. a plurality of switches for switching the latching relay to call a predetermined one of the machines and connect the predetermined one to the call circuit if the call circuit is not connected to the predetermined one; The present invention is characterized in that it comprises an impedance matching circuit for performing impedance matching of the parent unit, and that the impedance matching circuit supplies a driving current to the latching relay.

[Examples] Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram of an intercom system for a two-family residence to which the entrance cordless handset of the present invention is applied.
2, and a shared entrance slave unit 20 connected to each of the indoor units 11 and 12 is installed at the entrance. The entrance cordless handset 20 has a call button 2 for calling household A.
A call button 22 is provided for calling 1 and household B. These call buttons 21 and 22 can switch a relay built in the entrance handset 20, and a customer of household A can press the call button 21 to call the room. A call is made to the indoor unit 11, and the customer of household B presses a call button 22 to make a call to the indoor unit 12.

Next, the circuit configuration of the entrance cordless handset for realizing such a system will be explained. As shown in FIG.
1a, 12a and a communication circuit 30 are connected via a latching relay 40.

The latching relay 40 is a two-winding type two-circuit latching relay having a set side coil 41 and a reset side coil 42, one contact 43 is connected to the communication circuit 30, and the other contact 44 is connected to the impedance matching circuit 60. It is connected to the. The impedance matching circuit 60 is made up of a resistor R and a capacitor C, and performs impedance matching of each indoor unit 11, 12, and also serves as a power supply source for driving the latching relay 40 (the operation will be described later). ). When current flows from the impedance matching circuit 60 to the set side coil 41 of the latching relay 40, the contacts 43, 44
Both are switched to the SET side. Further, when the current from the impedance matching circuit 60 flows into the reset side coil 42, the contacts 43 and 44 are both switched to the RES side.

The switches 51 and 52 are integrated with the call buttons 21 and 22 shown in FIG.
1, 12 and each indoor unit 11,
12 is connected to the communication circuit 30, it has a function of switching the latching relay 40 to connect the other one.

The operation will be explained below.

First, the visitor presses the call button 21 in the state shown in Figure 2.
When (switch 51) is pressed, latching relay 4
Since the 0 contact 43 is on the SET side, a call is made to the indoor unit 11, and the communication circuit 30 of the entrance slave unit 20 remains connected to the indoor unit 11, so that a call can be made to the indoor unit 11.

Next, when the call button 22 (switch 52) is pressed in this state as shown in FIG. As shown in FIG. 3, the resistor R, the contact 44 of the latching relay 40, the reset side coil 42,
This causes the contacts 43 and 44 of the latching relay 40 to be switched to the RES side. Therefore, the communication circuit 30 of the entrance handset 20 is connected to the indoor unit 12, and a conversation can be made between the entrance handset 20 and the indoor unit 12. After that, when the indoor unit 11 is called by pressing the call button 21 (switch 51), the electric charge that was charged in the capacitor C of the impedance circuit 60 by the indoor unit 11 is transferred to the resistor R, the contact 43 of the latching relay 40, The current flows through the set side coil 41 and switch 51, switching the latching relay 40 to the SET side (returning to the state shown in FIG. 2). As a result, the communication circuit 30 of the entrance handset 20 is connected to the indoor unit 11, and the entrance handset 20 and the indoor unit 1 are connected to each other.
You can talk with 2.

[Effects of the Invention] As is clear from the above embodiments, according to the entrance slave unit of the present invention, the switch provided corresponding to each base unit can call each base unit and switch the relay. Since the power supply for driving the relay is supplied by a circuit (resistance and capacitor) for impedance matching of the base unit, the circuit configuration is very simple and the door switch can be shared by multiple base units. It is possible to reduce the cost and installation cost of the entire system.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of an intercom system for a two-family residence to which the present invention is applied, Fig. 2 is a doorway slave unit according to the present invention, Figure 3 is an explanatory diagram of the operation of the doorway slave unit, and Figure 4
The figure is a configuration diagram of a conventional intercom system for a two-family residence. 11, 12... Indoor unit (base unit), 20... Entrance slave unit, 30... Call circuit, 40... Latching relay, 51, 52... Switch, 60... Impedance matching circuit.

Claims (1)

[Claims] 1. A call circuit, a latching relay that connects the call circuit to one of a plurality of base units, and a latching relay that calls a predetermined one of the base units, and the call circuit is not connected to the predetermined one. a plurality of switches for switching the latching relay so as to connect the predetermined one of the communication circuits when the communication terminal is connected, and an impedance matching circuit for performing impedance matching of the base unit; An entrance slave unit characterized by supplying a driving current to a latching relay.