JPH10164244A - Interphone device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control plural states of a slave unit by superimposing direct current control data from a master unit to a slave unit on time division DTMF signal data which is transmitted and received between the master unit and plural slave units. SOLUTION: An interphone device has a DTMF generator 4 which generates DTMF data that separately corresponds to entire IDs of a slave unit according to control of a central processing unit U1, a direct current control circuit U2, a two-wire four-wire conversion circuit U3 for a master unit side data and a DTMF receiver 6 on a master unit side. Each slave unit has a DTMF receiver which receives DTMF data that is sent via a common line and a coincidence circuit which compares received data with an ID that is preliminarily set and outputs when they coincide with each other. Furthermore, a slave unit has a command data transmitting circuit, a direct current control data detecting circuit which detects direct current control data that is sent via the common line and a control circuit which controls the detected direct current control data as a control signal under the existence of a coincidence signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intercom apparatus, and in particular, superimposes DC control data from a master unit to a slave unit on time-division DTMF signal data transmitted and received between the master unit and a plurality of slave units. The present invention relates to an intercom device for controlling a plurality of states.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, there has been known an intercom apparatus (for example, a nurse call intercom apparatus) in which a master unit MQ2 and a plurality of slave units BQ21 to BQ30 are connected by common lines L11 and L12. . As shown in FIG. 3, master unit MQ2 and slave units BQ21 to BQ30 are connected by common lines L11 and L12, respectively.

The master unit MQ2 comprises a central processing unit 51 provided with a BCD counter 52, a control unit 53 and a logic circuit 54 comprising AND circuits 54A, 54B and 54C, a master unit DTMF.
Generator 55, master unit side data 2-wire 4-wire conversion circuit 5
6, a base unit side DTMF receiver 57, a decoder 58, a base unit side communication switch 59, a base unit side communication 2-wire 4-wire conversion circuit 60, a speaker amplifier 61a, a microphone amplifier 61b, a speaker 62, a microphone 63, and a BCD The output side of the counter 52 is a control unit 53, AND circuits 54A, 54B, 54
DTMF generator 55 on one input side and master side of C
The time-division data output side for outputting the time-division DTMF data S11 is connected to the 4-wire input side of the base unit-side data 2-wire 4-wire conversion circuit 56 and the base unit-side data 2-wire 4-wire conversion. The two-wire side of the circuit 56 is connected to the common line L11.

A 4-wire output side for outputting command data S15 of the 2-wire 4-wire conversion circuit 56 for the master unit data is a DTM for the master unit.
The output side of the decoder 58 is connected to the other input side of the AND circuits 54A, 54B, 54C of the logic circuit 54 provided in the central processing unit 51 via the F receiver 57, and the AND circuit 54A , 54
The control output sides of B and 54C are connected to the control unit 53.

A control unit 53 provided in the central processing unit 51
Is connected to the control side of the base unit side call switch 59, and the line side of the base unit side call switch 59 is connected to the common line L12.
Is connected to The two-wire / four-wire conversion side of the main-unit-side communication switch 59 is connected to the two-wire side of the two-wire / four-wire conversion circuit 60 for the main-unit-side communication. The side is connected to a speaker 62 via a speaker amplifier 61a.

The output side of the microphone 63 is a microphone amplifier 61b.
Is connected to the 4-wire input side of the 2-wire 4-wire conversion circuit 60 for telephone communication on the base unit side. Each of the slave units BQ21 to BQ30 includes a data transmission circuit 71 provided with a normal call switch SW11, an emergency call switch SW12, and a toilet call SW13, an encoder 72 to which command data S15 is input from the data transmission circuit 71, a code gate 73, and a slave. DTMF generator 74, 2-wire 4-wire conversion circuit 75 for handset side data, DTMF receiver 76 for handset side, matching circuit 77, ID setting circuit 78, call control circuit 79, handset side call switch 80, handset side 2-wire 4-wire conversion circuit 81 for call, speaker amplifier 82
a, a microphone amplifier 82b, a speaker 83, and a microphone 84.

The output side of the data transmission circuit 71 is connected to the input side of the encoder 72 via a data line, and the output side of the encoder 72 is connected to the input side of the code gate 73. The output side of the code gate 73 is supplied via a slave unit-side DTMF generator 74 to a slave unit-side data 2-wire 4-wire conversion circuit 75.
, And the two-wire side of the slave side data 2-wire 4-wire conversion circuit 75 is connected to the common line L11.

[0008] The 4-wire conversion circuit 75-4 for the slave side data
The line output side is connected to the input side of the slave unit-side DTMF receiver 76, and the DTMF data side that outputs the DTMF data S 11 is connected to one input side of the matching circuit 77. The match signal output side of the match circuit 77 that outputs the match signal S17 is connected to the control side of the code gate 73 and the input side of the speech control circuit 79, respectively.

ID setting circuit 7 for outputting ID data S16
8 is connected to the other input side of the matching circuit 77. The output side of the call control circuit 79 is connected to the control side of the handset side call switch 80, and the line side of the handset side call switch 80 is connected to the common line L12. The 2-wire 4-wire conversion side of the handset side call switch 80 is the handset side call switch 2.
The 2-wire 4-wire conversion circuit 81 is connected to the 2-wire side of the 4-wire conversion circuit 81.
The speaker 83 is connected via 2a.

The output side of the microphone 84 is a microphone amplifier 82b.
Is connected to the 4-wire input side of the 2-wire 4-wire conversion circuit 81 for the handset side communication. In such an intercom apparatus, the main unit MQ2 and the sub units BQ21 to BQ30 can communicate with each other, and different IDs are set in advance for the sub units BQ21 to BQ30, for example, for a nurse call or the like used in a hospital. used.

In order for the master unit MQ2 to know the requests and states from the slave units BQ21 to BQ30, the central processing unit 5 of the master unit MQ2
The DTMF generator 55 always has all the IDs (1 to 10) of the slave units BQ21 to BQ30.
) Is transmitted to the slave units BQ21 to BQ30 via the master unit side data 2-wire 4-wire conversion circuit 56 and the common line L11. At this time, the DTMF generator 55
DT from 1 to 0 depending on the output of the CD counter 52
Time-division DTMF data S1 composed of dial data by MF (signals used for touch-tone telephones)
Outputs 1. However, numbers 1 to 9 correspond to dial data “1” to “9”, and number 10 corresponds to dial data “0”. Here, time division DTMF
Since the data S11 is composed of a signal transmission time of 80 ms and a signal pause time of 20 ms, the period from 1 to 10 is 1 second, and the time division DTMF data S11 is a signal of 80 ms transmitted every 1 second. Will be.

Time division DTMF sent from master unit MQ2
In each of the slave units BQ21 to BQ30, the data S11 is transmitted to the slave unit DTM via the slave unit data 2-wire 4-wire conversion circuit 75.
The signal is received by the F receiver 76 and converted into a 4-bit digital signal. The converted time-division DTMF data S11 is output from the ID setting circuit 78 to
The data is compared with the D data S16.
To output the coincidence signal S17 to the code gate 73 and the communication control circuit 79. When the coincidence signal S17 is output to the sign gate 73, the sign gate 73 is closed.

At the time when the coincidence signal S17 is sent from the coincidence circuit 77, for example, the slave unit BQ21
When the switch SW11 of the data transmission circuit 71 is pressed to perform the “normal call”, command data S15 indicating the request and status of the slave unit BQ21 is transmitted to the encoder 72. The switches SW11 to SW of the data transmission circuit 71
13 is "normal call", "emergency call", "toilet call"
And the AND circuits 54A, 54B, 54 of the logic circuit 54 of the central processing unit 51 of the parent machine MQ2.
C is assumed to be supported.

In the encoder 72, the command data S15
Is converted into a signal for controlling the slave unit-side DTMF generator 74. The sign gate 73 is normally in an open state, but is in a closed state while the coincidence signal S17 is sent from the coincidence circuit 77. Therefore, the converted command data S15 is transmitted to the slave unit through the sign gate 73. DT corresponding to the state of the command data S15 by the DTMF generator 74
2-wire 4-wire conversion circuit 7 converted to MF signal for slave unit data
5 to the common line L11.

In the parent machine MQ2, a DTMF signal indicating the command data S15 from the child machine BQ21 is transmitted to the parent machine DTMF receiver 57 via the parent machine data 2-wire 4-wire conversion circuit 56.
To receive. The received DTMF signal is input to the decoder 58 and decoded. The decoded command data S15 indicates that the switch SW11 of the data transmission circuit 71 of the slave unit BQ21 has been pressed, and if the switch SW11 of the data transmission circuit 71 has been pressed, the decoded command data S15 and BCD The output of the AND circuit 54A of the logic circuit 54 provided in the central processing unit 51 becomes H level by the counter 52.

The request and status of the command data S15 are input to the control unit 53 of the parent machine MQ2. The BC of the BCD counter 52 provided in the central processing unit 51 during this time.
Since the D output is input, the control unit 53 can determine from which slave unit the command data S15 is the command data, so that the master unit MQ2 sets the slave unit BQ21.
The request and the state (normal call) sent from the server are known.

Further, master unit MQ2 controls the formation of a communication path in order to respond to the request and state (normal call) sent from slave unit BQ21. That is, the control unit 53 closes the master unit-side call switch 59 to form a call path. At the same time, the communication control circuit 79 of the slave unit BQ21 receives the match signal S17 and the control signal (not shown) of the time-division DTMF data S11 transmitted separately from the time-division DTMF data assigned to the slave unit BQ21. The side communication switch 80 is closed to form a communication path. Parent machine MQ2, child machine BQ2
Since the communication path is formed on both sides, the sound output from the microphone 63 of the master unit MQ2 is transmitted to the microphone amplifier 61b, the base unit side two-line / four-wire conversion circuit 60, and the base unit side call switch 59. It is transmitted to the communication line L12 via the slave unit BQ21, and is output from the speaker 83 via the slave unit-side call switch 80, the slave-unit-side 2-wire 4-wire conversion circuit 81, and the speaker amplifier 82a. The sound transmitted from the microphone 84 of the slave unit BQ21 is transmitted to the microphone amplifier 82b, the two-wire / four-wire conversion circuit 81 for the slave unit-side call,
0 to the communication line L12, and in the base station MQ2, the base station side communication switch 59, the base station side communication 2-wire 4-wire conversion circuit 6
0, output from the speaker 62 via the speaker amplifier 61a.

In the above example, the slave unit BQ21 to the master unit M
Although the call to Q2 and the intercommunication between the slave unit BQ21 and the master unit MQ2 have been described, the master unit MQ is transmitted from the other slave units BQ22 to BQ30.
The same function is performed with respect to the call to 2 and the intercommunication between the other slave units BQ22 to BQ30 and the master unit MQ2.

[0019]

In the conventional intercom apparatus, since the slave unit has only one circuit for determining the time-division DTMF signal data from the master unit, a plurality of state controls cannot be performed. The present invention has been made to solve such a problem, and superimposes DC control data from a master to a slave on time-division DTMF signal data transmitted and received between the master and a plurality of slaves. It is an object of the present invention to provide an intercom device capable of controlling a plurality of states of a slave unit.

[0020]

In order to achieve this object, an intercom apparatus according to the present invention is controlled by a central processing unit and has a base station having a calling function, and a base station connected to the base station by a common line and capable of talking with the base station. In an intercom apparatus including a plurality of slave units each having an ID set in advance,
The master unit circulates and generates the time division DTMF data corresponding to all the IDs of the slave units under the control of the central processing unit, and superimposes the DC control data for controlling the slave units on the time division DTMF data. A data transmission circuit for transmitting to the common line, and a receiver for receiving command data indicating a request and a status of the child device when transmitting the DC control data, each of the child devices being transmitted via the common line. A DTMF receiver for receiving the time-division DTMF data, a matching circuit for comparing the received time-division DTMF data with a preset ID, and outputting a match signal when they match, A command data transmission circuit for transmitting data to the central processing unit of the master unit via a common line and a DC control data transmitted via the common line are detected. A DC control data detecting circuit for, and a control circuit controlled as a control signal the detected DC control data in the presence of a coincidence signal.

In such a television intercom apparatus, a master unit controlled by a central processing unit and having a calling function is connected to a plurality of slave units each having a preset ID by a common line. The central processing unit provided in the master unit transmits the time-division DTMF data corresponding to all the IDs of the slave units to DT.
Generated by circulating in the MF generator.

At this time, the DC control data is superimposed on the time-division DTMF data and transmitted to the common line by the data transmission circuit.
Upon transmitting the DC control data, the receiver receives command data indicating the request and status of the slave unit. Each of the slave units is a time-division DTMF transmitted via a common line.
The data is received by the DTMF receiver, and the received time division D
The TMF data is compared with a preset ID, and when they match, a match signal is output from the match circuit.

At the time when the coincidence signal is being output, the command data is transmitted from the command data transmission circuit to the central processing unit of the master unit via the common line. DC control data sent via a common line is detected by a DC control data detection circuit,
The detected DC control data is output as a control signal in the presence of the coincidence signal.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an intercom apparatus according to the present invention will be described below in detail with reference to FIGS. As shown in FIG. 1, terminals T1, T2, and T3 of master unit MQ1 are connected to slave units BQ1 to BQ10 via common lines L1, L2 and communication line L3.
, Pins P1a, P1b, P1c to P10a,
They are connected to P10b and P10c, respectively.

The master unit MQ1 has a BCD counter 1, a control unit 2
A central processing unit U1 provided with a logic circuit 3 comprising AND circuits 3a, 3b and 3c, a DC control circuit U2, a 2-wire 4-wire conversion circuit U3 for master unit data, a DTMF generator 4 for master unit, and a DTMF for master unit A receiver 6, a decoder 5, a base unit side call switch 7, a base unit side call 2-wire 4-wire conversion circuit 8,
Speaker amplifier 9a, microphone amplifier 9b, speaker 10
a, a microphone 10b, and the output side of the BCD counter 1 is connected to the input side of the master unit DTMF generator 4 and the input side of the control unit 2, and outputs the time-division DTMF data S1 of the master unit DTMF generator 4. The time-sharing data output side is connected to the time-sharing terminal T4 of the master unit data 2-wire 4-wire conversion circuit U3, and the master unit A-line terminal T6 of the master unit data 2-wire 4-wire conversion circuit U3 is connected to Connected to terminal T1.

The terminal T2 is connected to the master terminal B side terminal T7 of the master unit data 2-wire 4-wire conversion circuit U3, and outputs a command data S5 of the master unit data 2-wire 4-wire conversion circuit U3. The terminal T5 is connected to the decoder 5 via the parent device side DTMF receiver 6. The output side of the decoder 5 is connected to one input side of the AND circuits 3a, 3b, 3c of the logic circuit 3 provided in the central processing unit U1, and the control output side of the AND circuits 3a, 3b, 3c is connected to the control unit 2 Is connected to

The other input sides of the AND circuits 3a, 3b, 3c are connected to the output side of the BCD counter 1. The DC control circuit U2 has a lamp control transistor Q1 and a call control transistor Q2,
The base of the lamp control transistor Q1 is connected via a resistor R14 to the control output side of the control unit 2 provided in the central processing unit U1 for outputting the lamp control data S3.

A power supply + B is connected to the emitter of the lamp control transistor Q1, and a resistor R13 is connected between the emitter and the base. The collector of the lamp control transistor Q1 is connected via a resistor R16 to a connection point between series resistors R15 and R17, one end of which is connected to the power supply + B and the other end is connected to a reference potential point.

The base of the call control transistor Q2 is connected via a resistor R18 to the control output of the control unit 2 provided in the central processing unit U1 for outputting the call control data S4. A reference potential point is connected to the emitter of the call control transistor Q2, and a resistor R19 is connected between the emitter and the base.

The collector of the call control transistor Q2 is connected via a resistor R20 to a connection point between series resistors R15 and R17, one end of which is connected to the power supply + B and the other end of which is connected to a reference potential point. The master unit side data 2-wire 4-wire conversion circuit U3 has a command data output operational amplifier OP1, an A line side operational amplifier OP2, and a B line side operational amplifier OP3, and the (−) input side of the A line side operational amplifier OP2 is the master unit side. 2 for data
The connection point between the resistors R1 and R2 connected in series between the time division terminal T4 of the line 4-wire conversion circuit U3 and the main unit A-line side terminal T6 is connected.

The (+) input side of the A-line side operational amplifier OP2 is connected to the series resistors R15 and R17 provided in the DC control circuit U2.
The output side of the A-line side operational amplifier OP2 is connected to the A-side terminal T6 for the base unit via a resistor R5, and the B-side terminal T7 for the base unit via resistors R6 and R11 connected in series. Each is connected. The (+) input side of the operational amplifier OP3 on the B line side is a reference voltage REF that outputs half the voltage of the power supply + B.
Is connected, and the (-) input side of the B-line side operational amplifier OP3 is connected to a connection point of the resistors R3 and R4 connected in series between the master unit A-line side terminal T6 and the master unit B-side terminal T7. I have.

The output side of the operational amplifier OP3 on the B line side is connected to a resistor R1.
2, a master terminal B7 for the base unit and a resistor R connected in series.
7 and R10, respectively. The A-line side terminal T6 for the parent machine is connected to the (+) input side of the operational amplifier OP1 for command data output via resistors R7 and R9 connected in series, and the output side of the operational amplifier OP1 for command data output is connected to the control terminal T5. It is connected.

The (-) input side of the operational amplifier OP1 for command data output has a resistor R6 connected in series via a resistor R8.
And R11. The control output side of the control unit 2 provided in the central processing unit U1 is connected to the control side of the base unit side call switch 7, and the line side of the base unit side call switch 7 is connected to the terminal T3.

The two-wire / four-wire conversion side of the main-unit-side communication switch 7 is connected to the two-wire side of the two-wire / four-wire conversion circuit 8 for the main-unit-side communication.
The four-wire output side of the main-unit-side two-wire / four-wire conversion circuit 8 is connected to a speaker 10a via a speaker amplifier 9a. The output side of the microphone 10b is connected via a microphone amplifier 9b to the 4-wire input side of the base-phone-side 2-wire 4-wire conversion circuit 8.

Each of the slave units BQ1 to BQ10 includes a call display / call control circuit U4, a DC detection circuit U5,
A data transmission circuit 11 provided with a normal call switch SW1, an emergency call switch SW2, and a toilet call SW3; an encoder 12 to which command data S5 is input from the data transmission circuit 11; a code gate 13; a slave unit-side DTMF generator 14; Data 2-wire 4-wire conversion circuit 15, slave unit D
TMF receiver 16, matching circuit 17, ID setting circuit 1
8, a NAND circuit 21, a lamp LA, a handset side call switch 22, a handset side call two-wire / four-wire conversion circuit 23, a speaker amplifier 24a, a microphone amplifier 24b, a speaker 25a, and a microphone 25b.

The output side of the data transmission circuit 11 is connected to the input side of the encoder 12 via a data line, and the output side of the encoder 12 is connected to the input side of the code gate 13. The output side of the code gate 13 is supplied via a slave side DTMF generator 14 to a slave side data two-wire / four-wire conversion circuit 15.
The two-line A line and the two-line B line of the slave-side data two-wire four-wire conversion circuit 15 are connected to the pin P1a and the two-wire B line, respectively, to the pin P1b.

The 4-wire conversion circuit 15-4 for the slave unit data
The line output side is connected to the input side of the slave unit side DTMF receiver 16, and the DTMF data side for outputting the DTMF data S 1 is connected to one input side of the matching circuit 17. The coincidence signal output side of the coincidence circuit 17 that outputs the coincidence signal S7 is connected to the control side of the code gate 13 and the coincidence signal input terminal T11 of the call display / call control circuit U4, respectively.

ID setting circuit 18 for outputting ID data S6
Is connected to the other input side of the matching circuit 17. The call switch control terminal T12 of the call display / call control circuit U4 is connected to the control side of the handset side call switch 22, and the line side of the handset side call switch 22 is connected to the pin P.
1c.

The two-wire / four-wire conversion side of the handset-side communication switch 23 is connected to the two-wire side of the two-wire / two-wire conversion circuit 23 for the handset-side communication. The 4-wire output side is connected to a speaker 25a via a speaker amplifier 24a. The microphone 25b is connected via a microphone amplifier 24b to the four-wire input side of the two-wire / four-wire conversion circuit 23 for the handset side communication.

The DC detection circuit U5 has a DC detection operational amplifier OP4, and the DC detection circuit U5 connected to the pin P1a.
The resistors R22 and R23 connected in series are connected to the A-side terminal T8 for the slave unit and the B-side terminal T9 to which the pin P1b is connected, and the connection point between the resistors R22 and R23 is used for DC detection. The (+) input side of the operational amplifier OP4 is connected. The A-line terminal T8 for the slave unit is connected to the (-) input side of the operational amplifier OP4 for DC detection via the resistor R21, and the (-) input side of the operational amplifier OP4 for DC detection and the call display / communication control terminal T1.
3, a resistor R20 is connected.

The output side of the operational amplifier OP4 for direct current detection is connected to the input side of a voltage detection circuit 19 provided in the call display / call control circuit U4 via a call display / call control terminal T13. The call display / call control circuit U4 includes a voltage detection circuit 19, AND circuits 19a and 19b, a call display one-shot timer 20a, and a call control one-shot timer 20b.
The detection output side for outputting S8 is connected to one input side of the AND circuit 19a, and the detection output side for outputting the call data S9 of the voltage detection circuit 19 is connected to one input side of the AND circuit 19b.

A match signal input terminal T11 is connected to the other input sides of the AND circuits 19a and 19b.
a and 19b are output one-shot timers 20a for call display and one-shot timers 2 for call control, respectively.
0b is connected to the input side. The output side of the one-shot timer 20b for call control is a call switch control terminal T12.
The output side of the call display one-shot timer 20a is connected to a call display / call control terminal T10, and the call display / call control terminal T10 is connected to one input side of the NAND circuit 21.

The other input of the NAND circuit 21 is connected to the data line related to SW3 of the data transmission circuit 11, and the negative output of the NAND circuit 21 is connected to the power supply + B via the lamp LA. In such an intercom apparatus, the time-division DTMF data from the base unit side DTMF generator 4 provided in the base unit MQ1 is set to, for example, 80 mS data and the interval of 20 mS is set as the unit cycle at the time of standby. Time division DTMF data of 1 to 10 corresponding to each of BQ10 is transmitted.

Here, the resistance of the DC control circuit U2 is R15 = R1.
In step 7, R16 is set so that the voltage at the connection point between the resistors R16 and R17 becomes VREF + 2V when the lamp control transistor Q1 is on. In the standby state, a voltage of 1/2 Vcc (hereinafter referred to as VREF) of a divided voltage value of a resistor set to a constant R15 = R17 is input to the + input side of the A-line side operational amplifier OP2.

The control unit 2 of the central processing unit U1 has slave units BQ1 to BQ1 to
When the command data of the toilet call corresponding to the toilet call SW3 is received from the BQ10, the control enters the lamp control, and outputs the lamp control data S3 (L) to the base of the lamp control transistor Q1.
(At this time, the call control transistor Q2 is turned off under the control of the central processing unit U1.) When the lamp control data S3 (L) is output to the base of the lamp control transistor Q1, the lamp control transistor Q1 is turned on. Then, the + input side of the A-line side operational amplifier OP2 becomes VREF + 2V, and the DC potential of the parent device A-line side terminal T6 becomes VREF + 2V.

If the resistances R1 = R2 = R3 = R4 are set, the gain of the operational amplifier OP3 on the B line side becomes (R2 / R
1) and the gain becomes -1 from R3 = R4, and the potential of the parent device B-side terminal T7 becomes (VREF-2V). When the control unit 2 of the central processing unit U1 controls the call control of the slave unit BQ1, the lamp control transistor Q
The call control data S4 (H) is output to the base of the first transistor and the base of the call control transistor Q2.

At this time, the main unit A line side terminal T6 and the main unit B
The potentials of the line side terminal T7 are (VREF-2V), (VREF
REF + 2V). As an example, if + B = 24V, VREF = 12V. Therefore, the A-line side terminal T6 for the master unit,
12V and 12V during standby, 14V and 10V during lamp control, and 10V and 14V during call control are output to the main unit B-line side terminal T7.

Next, an example in which the DC potential difference from the master unit MQ1 is detected by the slave units BQ1 to BQ10 will be described with reference to FIG. Resistors R20, R21, R2 provided in the DC detection circuit U5
2, R23 is set to R20 = R21, R22: R23 = 3: 1. The voltage applied to the base unit A-line side terminal T6 and the base unit B-line side terminal T7 is applied to the divided potential (reference potential) of R22 = R23 and the base unit A-line side terminal T6. An inverted output of the difference between the applied potentials is output while being superimposed on the reference potential.

Therefore, 12 V during standby, 8 V during lamp control, and 16 V during call control are detected, and lamp control control and call control control are performed using these potentials. For example, when the toilet call switch SW3 provided in the data transmission circuit 11 of the slave unit BQ1 is pressed, the lamp control data S3 (L) is controlled by the control unit 2 provided in the central processing unit U1 of the master unit MQ1. When the voltage is applied to the base of the lamp control transistor Q1 provided in the DC control circuit U2, the lamp control transistor Q1 operates.

When the lamp control transistor Q1 operates, the parent device A line side terminal T6 and the parent device B line side terminal T7 superimposed on the time division DTMF data of the dial signal 1.
Are 14V and 10V. This allows the slave unit BQ1
The A-line terminal T8 for the slave unit provided in the DC detection circuit U5 has a voltage of 14 V, and the B-side terminal T9 for the slave unit has a voltage of 10 V. The (-) of the DC detection operational amplifier OP4 provided in the DC detection circuit U5.
The side input is 14V, the (+) side input is 11V, and the call display / call control terminal T13 is 8V.

When the call display / call control terminal T13 becomes 8V, the voltage detection circuit 19 provided in the call display / call control circuit U4 detects 8V and enters the call display mode, and outputs the lamp permission data S8 to one of the AND circuits 19a. To one input side of the AND circuit 19a from L level to H level.
Change to level. When one input side of the AND circuit 19a is changed from L level to H level and the coincidence signal S7 is output to the other input side by the coincidence circuit 17, the output side of the AND circuit 19a becomes H level continuously and is used for calling display. The one-shot timer 20a operates.

When the call display one-shot timer 20a is operated, the call display / call control terminal T10 is continuously at H level, and the toilet call switch S of the NAND circuit 21 is turned on.
When the input side of W3 and the call display one-shot timer 20a becomes H level and the output side becomes L level, the lamp LA indicating the toilet call is turned on. The illuminated lamp LA goes out after a certain period of time.

When the call switch SW1 of the data transmission circuit 11 of the slave unit BQ1 is pressed, the call control data S4 (H) is controlled by the control unit 2 provided in the central processing unit U1 of the master unit MQ1. When applied to the base of the call control transistor Q2 provided in the circuit U2, the call control transistor Q2 operates. In addition, the control unit 2 closes the base unit side call switch 7.

When the call control transistor Q2 operates, the voltages of the parent device A line side terminal T6 and the parent device B line side terminal T7 superimposed on the time division DTMF data of the dial signal 1 are 10V and 14V. Become. Thereby, the slave unit B
A-line terminal T for slave unit provided in DC detection circuit U5 of Q1
8 is 10 V, the terminal B 9 for the slave unit is 14 V, and the input of the DC detection operational amplifier OP 4 provided in the DC detection circuit U 5 is 13 V on the (+) side and 10 V on the (−) side. T10 becomes 16V.

When the call display / call control terminal T10 becomes 16V, the voltage detection circuit 19 provided in the call display / call control circuit U4 detects 16V and enters the call mode, and the call data S8 is inputted to one input of the AND circuit 19b. And changes one input side of the AND circuit 19b from L level to H level. When the input side of the AND circuit 19b is changed from L level to H level and the coincidence signal S7 is output from the coincidence circuit 17, the output side of the AND circuit 19b becomes H level intermittently, and the one-shot timer 20b for speech control operates.

When the call control one-shot timer 20b operates, the call switch control terminal T12 goes to the H level, and the slave unit call switch 22 is controlled and closed. This allows the parent machine MQ1 and the child machine BQ1 to communicate via the common line L3. The closed handset talk switch 22 is opened after a certain period of time. The operation of each circuit other than the above description is the same as that of the conventional circuit, and the description is omitted.

[0057]

As is apparent from the above description, the intercom apparatus according to the present invention can be controlled by a central processing unit and has a telephone function, and can be connected to the parent apparatus by a common line and can communicate with the parent apparatus. In an intercom apparatus provided with a plurality of slave units each having a preset ID, the master unit circulates and generates time-division DTMF data corresponding to all IDs of the slave units under the control of a central processing unit.
An F generator, a data transmission circuit that superimposes DC control data for controlling the slave unit on the time-division DTMF data and sends the data to a common line, and receives command data indicating a request and a state of the slave unit when sending the DC control data. Each of the slave units has a DTMF receiver that receives the time-division DTMF data transmitted via a common line, and compares the received time-division DTMF data with the preset ID. A matching circuit that outputs a match signal when a match occurs, a command data transmission circuit that sends command data to the central processing unit of the master unit via a common line when the match signal is being output, and a command data sending circuit that sends the command data via the common line DC control data detection circuit for detecting the detected DC control data, and the detected DC control data is controlled as a control signal in the presence of the coincidence signal. Control circuit to superimpose DC control data from the master unit to the slave unit on time-division DTMF signal data transmitted and received between the master unit and the plurality of slave units, thereby controlling a plurality of states of the slave unit. .

[Brief description of the drawings]

FIG. 1 is a block diagram of a base unit showing one embodiment of an intercom apparatus according to the present invention.

FIG. 2 is a block diagram of a slave unit showing an embodiment of an intercom apparatus according to the present invention.

FIG. 3 is a block diagram of a conventional intercom apparatus.

[Explanation of symbols]

4... Master unit DTMF generator (DTMF generator) 6... Master unit DTMF receiver (receiver) 11... Data transmission circuit (command data transmission circuit) 16. ... Slave-side DTMF receiver (DTMF receiver) 17... Match circuit 20a... Call control one-shot timer (control circuit) 20b. Shot timer (control circuit) U1 Central processing unit U2 DC control circuit (data transmission circuit) U3 ... 2-wire 4-wire conversion circuit for master unit data ( Data transmission circuit) U4: Call display / call control circuit (DC control data detection circuit) U5: DC detection circuit (DC control data detection circuit) 19: Voltage detection Circuit (DC control Data detection circuit) MQ1 ... master unit BQ1-BQ10 ... slave unit L1, L2 ... common line L3 ... communication line (common line) S1・ ・ ・ ・ ・ ・ Time-division DTMF data S2 ・ ・ ・ ・ ・ ・ DC control data S5 ・ ・ ・ ・ ・ ・ Command data S6 ・ ・ ・ ・ ・ ・ ID S7 ・ ・ ・ ・ ・ ・ Match signal S8 ・ ・ ・・ ・ ・ Lamp permission data (control signal) S9 ・ ・ ・ ・ ・ ・ Talk data (control signal)

Claims (1)

[Claims] A master unit (MQ1) controlled by a central processing unit (U1) and having a call function, and a common line (L) connected to the master unit.
1, L2, L3) and a plurality of slave units (BQ1 to BQ1 to
BQ10), the master unit controls the time-division DTMF data (S1) corresponding to all IDs of the slave units under the control of the central processing unit.
DTMF generator (4) for circulating and generating DC control data (S2) for controlling the slave unit
A data transmission circuit (U2, U3) that superimposes the TMF data on the common line and transmits the DC control data, and a receiver (6) that receives command data (S5) indicating a request and status of the slave unit when transmitting the DC control data. ), And each of the slave units receives a DTMF receiver (1) that receives the time-division DTMF data transmitted through the common line.
6), the received time-division DTMF data is compared with the preset ID, and when they match, a match signal (S7)
And a command data transmitting circuit (11) for transmitting the command data (S5) to the central processing unit of the master unit via the common line at a time when the coincidence signal is output. ), A DC control data detection circuit (U4, U5) for detecting DC control data transmitted via the common line, and a control signal (S8, S9) for detecting the detected DC control data in the presence of the coincidence signal. And a control circuit (20a, 20b, 21) controlled as follows.