GB2084834A - Improvements in or relating to universal intercommunications terminals - Google Patents

Abstract

A universal intercommunication terminal 1 comprises a telephone set, keys 15, signalling members 19, and connection members 20. The terminal is connected to a central unit by three pairs of lines comprising a conversation pair 3, 4, a control pair 16, 17, and a power supply pair 23, 24. <IMAGE>

Description

SPECIFICATION Improvements in or relating to universal intercommunications terminals The invention relates to a universal intercommunication terminal.

Intercommunications installations comprising mechanical stations are already known.

Such stations comprise a combined telephone set, keys, signalling members and connection members. The keys are of the locking key type, and their operation always presents a certain difficulty which is a burden to the user. Moreover, the operation of the keys of such mechanical stations gives rise to a certain operating noise, which is an important drawback especially when several stations are used in the same room. The major drawback of such mechanical stations lies in the fact that their operability is limited and is difficult to extend, both in increasing their capacity and in adding supplementary equipment. Furthermore, the connection of the mechanical station to the installation requires large numbers of cables, and the connection wiring varies as a function of the utility of the station.

Because of the fact that the mechanical stations vary according to the operability of the installation, it is necessary to provide a large variety of stations, which leads to high selling prices, deriving from their manufacture, storage and sale. Standardisation is therefore very difficult to attain.

Installations of the semi-electronic type are also known. These installations also have a certain number of drawbacks, in particular regarding the capacity of the cables and the limitation on their operability. The central unit is very bulky, and the subscriber interfaces vary as a function of the utility of the stations.

In certain semi-electronic installations, the subscriber interface is disposed inside the connection box of each station, and the switching noise can be heard.

According to the invention, there is provided a universal intercommunication terminal comprising a combined telephone set, keys, signalling members, connection members, and a connection for connecting internal equipment of the terminal to a central unit, the connection comprising three pairs of lines constituting a conversation pair, a control pair and a power supply pair, for an operation which is limited to detecting which magnetically returned key of simple contact type has been operated, followed by transmitting the data to the central unit, and to analysing the data supplied by the central unit for controlling the signalling members.

It is possible to provide a practically silent intercommunication terminal comprising keys which are of very soft operation and require only a limited connection wiring whatever the capacity of the installation. Moreover, the operability of installations provided with such terminals can be extended, and supplementary equipment can be easily added.

The invention will be further described, by way of non-limiting example, with reference to the accompanying drawings, in which: Figure 1 is a block diagram of an intercommunication terminal constituting a preferred embodiment of the invention; and Figure 2 is a sectional elevation of the terminal of Fig. 1.

Reference will be made to Fig. 1.

The terminal 1 comprises inter alia a conversation circuit 2 which by means of a pair of conversation lines 3, 4 connects the terminal to a central unit. The conversational circuit 2 provides for speech transmission between the combined telephone set 5 and the pair of conversation lines 3, 4. A switch hook 6 is disposed in the second conversation line 4.

The conversation circuit 2 also provides a connection 7 to an amplifier 8 by way of a conversation preamplifier 9. The amplifier 8 is connected to a loudspeaker 10 and to two potentiometers 11 and 1 2 for adjusting the sound level. One of the potentiometers 11 cooperate with a call oscillator 1 3 and the second 1 2 is for the amplified reception section. The conversation circuit 2 is based on electronic telephonometry. A supplementary output 5a connected to the preamplifier 9 enables it to be connected to an apparatus for recording the conversation.

The terminal 1 also comprises a control member 1 4. The control member is formed from a single chip microprocessor comprising integrated read only and random access memories (ROM, RAM). The microprocessor, which is adaptable to and extendable in relation to the utility of the terminal, processes signals from keys 1 5. Each key operation is recorded by the microprocessor and transmitted to a central unit (not shown) by way of a pair of control lines 16, 1 7. The central unit requires the transmission of the data recorded by the microprocessor. In addition, the microprocessor operates a control unit 1 8 for signalling elements 1 9. The signalling can be luminous, sound or other signalling.The decision for this control is taken by the central unit which decides which signals to engage, and gives the order to the microprocessor.

The microprocessor processes the information received by the connection member and controls the corresponding signal.

The terminal 1 is provided with a connection member 20 connected by the pair of control lines 16, 1 7 to the central unit. The connection is based on half-duplex synchronous data transmission. The connection member 20 provides for the exchange of information between the control member 14 of the terminal 1 and the central unit.

In addition, the terminal 1 comprises a power supply device 21, which provides power supply for the control member 14 and connection member 20. The power supply is obtained by way of a regulator 22 from a 1 2 Volt supply through two supply wires 23, 24.

The conversation circuit 2 is however re motely supplied by the central unit.

Reference will now be made to Fig. 2.

Each terminal 1 comprises a lower shell 25 covered by an upper shell 26. The upper shell 26 is covered by an adhesive heat-blistered or heat-shrunk film 27 which personalises the capacity and as a consequence the equipment of the terminal. The film 27 comprises preferably punched holes 28 through which the keys 1 5 rigid with or connected to a guide member 30 pass. The keys 1 5 are single contact magnetic return keys, whatever their function, the function being determined by the central unit. The number of keys 1 5 is variable and can be situated within a fork, the maximum number being of the order of 32 keys, this number being determined by the utility of the terminal 1.

In addition, the film 27 comprises heatblistered bosses 31 which cover the signalling elements 1 9 and in particular the luminous elements, such as light emitting diodes. The bosses 31 serve to diffuse the light emitted by the elements 19, thus accentuating the display of the luminous elements 1 9. The elements 1 9 and the keys 1 5 are connected to a printed circuit 32.

The film 27 can easily be silk-screen printed, thus enabling the appearance of the terminal to be enhanced and providing information on the utility of the terminal.

In addition, the terminal comprises a descriptive band 33 covering labels 34 on which any information can be given. Each label 34 is associated with a luminous signal.

The terminal 1 comprises a basic station printed-circuit board 35 on which the conversation circuit 2, the control member 14, the connection member 20, the amplified reception section 5 and the power supply unit 21 are disposed. The three connection pairs 3-4, 16-17 and 23-24 lead to this board.

All the various elements heretofore described enable a universal terminal to be obtained, the utility of which is not limited to any particular function but can be extended to other functions, such as an operating desk for an automatic switchboard.

Claims (10)

1. A universal intercommunication terminal comprising a combined telephone set, keys, signalling members, connection members, and a connection for connecting internal equipment of the terminal to a central unit, the connection comprising three pairs of lines constituting a conversation pair, a control pair and a power supply pair, for an operation which is limited to detecting which magnetically returned key of simple contact type has been operated, followed by transmitting the data to the central unit, and to analysing the data supplied by the central unit for controlling the signalling members.

2. A terminal as claimed in claim 1, further comprising a conversation circuit based on electronic telephonometry, a control member, a connection member for connection to the central control unit, and a power supply device.

3. A terminal as claimed in claim 2, in which the control member is a single chip microprocessor for processing signals from the keys and for controlling the signalling members.

4. A terminal as claimed in any one of the preceding claims, comprising a mechanical structure arranged to allow easy modification of the internal equipment with respect to the number of keys and of signalling members.

5. A terminal as claimed in claim 4, in which the mechanical structure includes an adhesive heat-blistered film pierced by holes for passage of the keys, and serving as a diffuser for the signalling elements which are light-emitting elements, the film having formed thereon by means of silk-screen printing information regarding the utilisation of the keys and of the signalling elements.

6. A terminal as claimed in claim 4 or 5, in which the mechanical structure includes a descriptive band provided with labels carrying any information associated with the signalling elements.

7. A terminal as claimed in any one of claims 4 to 6, when dependant on claim 2, in which the mechanical structure comprises a basic station printed-circuit board, on which the conversation circuit, the control member, the connection member, an amplifier reception section and the power supply device are disposed, the three pairs of lines leading to the board.

8. A terminal as claimed in claim 3 or in any one of claims 4 to 7 when dependent on claim 3, in which the microprocessor is arranged to test the control member, the connection member for connection to the central control unit, and the signalling members.

9. A terminal as claimed in claim 2, 3, 7 or 8, or in any one of claims 4 to 6 when dependent on claim 2, in which the connection to the central control unit is based on half-duplex synchronous data transmission.

10. A universal intercommunication terminal substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.