JP3342609B2 - Loudspeaker intercom system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loudspeaker-type intercom apparatus, and more particularly to a loudspeaker-type intercom apparatus used in hospitals and the like for clearly distinguishing a state of waiting, calling, and talking.

[0002]

2. Description of the Related Art Conventionally, in hospitals and the like, there has been known a loudspeaker-type intercom apparatus for making a call between one intercom master unit provided in a nurse station or the like and a plurality of intercom slave units provided in each hospital room. ing. As shown in FIG. 2, the intercom master unit 51 of the loudspeaker-type intercom device includes a plurality of intercom slave units 52 connected to each other via a connection line L2.
Selection switch 5 corresponding to each intercom slave unit for connecting the intercom master unit 51 and the intercom master unit 51 in a communicable state.
7 is provided. The tuning switch 57 is connected in parallel with the call detection circuit 53 and the power supply circuit 55 via a diode D52.
, A contact 2 connected to the intercom slave unit 52 via a connection line L2, a contact 3 connected to a transmission / reception circuit 56, and contacts 4, 5, and 6. The diode D52 is connected to the call detection circuit 53 via the diode D51 and to the power supply circuit 55 via the resistor R51 and the light emitting diode LED51. Intercom slave unit 52
Is composed of a call holding circuit 58, a call switch 59, a speaker 60, and a capacitor C2.
Is connected to the call holding circuit 58 of the intercom slave unit 52, and the capacitor C2 and the speaker 60 connected in series are connected in parallel to the call holding circuit 58. The call switch 59 is connected to the call holding circuit 58.

In such a loudspeaker-type intercom apparatus, when the intercom master unit 51 is in a standby state, the call holding circuit 58 is turned off unless the call switch 59 of the intercom slave unit 52 is depressed.
No current flows through one light emitting diode LED51, and the light emitting diode LED51 is turned off. In this state, when the call switch 59 of the intercom slave unit 52 is pressed, the power supply circuit 54 of the intercom master unit 51 passes through the diodes D51 and D52, the contacts 1 and 2 of the tuning switch 57, and the connection line L2. Call holding circuit 5 of intercom slave unit 52
Current flows to 8. When a current flows through the call holding circuit 58, the current continues to flow through the above-described path due to the action of the call holding circuit 58, whereby a current also flows from the power supply circuit 55 to the light emitting diode LED51 of the intercom master device 51, and the light emitting diode LED51 Lights to indicate that there is a call. When a current flows from the power supply circuit 54 to the call holding circuit 58, a call is detected by the call detection circuit 53 and a ringing tone is generated.

The intercom master unit 51 confirms the ringing tone,
When the tuning switch 57 corresponding to the light emitting diode LED 51 being lit is pressed, the contact 1-2 is opened,
No current flows to the light emitting diode LED51, and the light emitting diode LED51 is turned off. As a result, the power supply to the call holding circuit 58 of the intercom slave unit 52 is cut off,
The call holding circuit 58 is reset. When the contacts 2-3 are connected, the transmission / reception circuit 5 of the intercom master unit 51 is connected.
From 6, a path is formed to the capacitor C 2 of the slave unit 52 and the speaker 60 via the connection line L 2 via the tuning switch 57, so that the interphone master unit 51 and the interphone slave unit 52 can communicate with each other.

[0005] When the call from the intercom master unit 51 to the intercom slave unit 52 is completed and the channel selection switch 57 of the intercom master unit 51 is pressed again, the contacts 2-3 are opened, and the contacts 1-2 are connected. Intercom master unit 51 enters a standby state.

[0006]

In such a loudspeaker-type intercom device, it is difficult to draw attention because the light emitting diode is lit only when calling, and it is turned off during a call. In the case where a handset is installed, which handset is being talked to can only be determined by the state of the channel selection switch. Also,
There is a risk that the tuning switch may be forgotten to be returned.

In order to solve the above-mentioned problems, the present invention can clearly distinguish a standby state, a calling state, and a talking state, and a loudspeaker interphone which does not forget to return a channel selection switch. It is intended to provide a device.

[0008]

In order to achieve this object, a loudspeaker-type intercom apparatus according to the present invention calls a main unit having a power supply circuit and a transmission / reception circuit via a connection line. A plurality of intercom slave units each having a call holding circuit and a speaker connected in parallel are connected, and the intercom master unit has a light emitting diode, a make contact, a common contact, and a break contact that are interlocked by sliding of the mover. A self-locking interlocking two-circuit selection switch composed of a first circuit, a make contact, a common contact, and a second circuit having a break contact is provided for each of a plurality of intercom slave units, and the first selection switch of the selection switch is provided.
The make contact of the circuit is connected to the power supply circuit, the common contact is connected to the connection line, the break contact is connected to the transmitting and receiving circuit, and the make contact of the second circuit of the tuning switch corresponds to each of a plurality of intercom slave units. Connected to a reference potential point via a lighting drive element provided, a common contact is connected to a power supply circuit via a light emitting diode, and a break contact is connected to the reference potential point, corresponding to each of a plurality of intercom slave units. A control element that turns off the light-emitting diode by turning off the light-emitting drive element during standby and turns on the light-emitting drive element by holding the call holding circuit when calling, and a light-emitting drive element during operation of the control element. OFF intermittently
A flashing circuit for driving the light emitting diode to flash on and off, a common contact of a second circuit of the tuning switch during a call,
The break contact is connected so as to turn on the light emitting diode.

[0009] In this loudspeaker-type intercom apparatus, the provision of the blinking circuit makes it possible to clearly distinguish the standby, calling, and talking states, and to avoid forgetting to return the channel selection switch.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a preferred embodiment of a loudspeaker-type intercom apparatus according to the present invention.

As shown in FIG. 1, in the loudspeaker type intercom apparatus of the present invention, the intercom master unit 1 having the power supply circuit 3 and the transmission / reception circuit 5 includes a call holding circuit 8a and a speaker 10 connected in parallel via a connection line L1. Are connected to each other.

The intercom master unit 1 has a first circuit 7a having a make contact m1, a common contact c1, and a break contact b1, which are interlocked with the light emitting diodes LED1, LED2,... Contact c2,
A self-locking two-circuit tuning switch 7 composed of a second circuit 7b having a break contact b2 is provided corresponding to each of the plurality of intercom slaves 2a, 2b.

The make contact m1 of the first circuit 7a of the tuning switch 7 is connected to the power supply circuit 3 via a diode D4 and resistors R2 and R1, the common contact c1 is connected to a connection line L1,
The break contact b1 is connected to the transmission / reception circuit 5. The power supply circuit 3 is connected to a connection point between the resistor R2 and the diode D4 via the diodes D1 and D2.

The make contact m2 of the second circuit 7b of the tuning switch 7 is connected to the reference potential point via the collector and the emitter of the lighting drive element Q3, and the common contact c2 has the anode connected to the power supply circuit 3 via the resistor R3. Connected light emitting diode L
Connected to the cathode of ED1, the break contact b2 is connected to a resistor R
5 is connected to the reference potential point.

The intercom master unit 1 has a lighting control element Q1 for turning on the lighting drive element Q3 when the call holding circuit 8a is being held, and an intermittent ON and O of the lighting drive element Q3.
And a blinking circuit 6 for flip-flop.

The emitter of the lighting control element Q1 is connected to the power supply circuit 3, the base is connected to the connection point of the resistors R1 and R2, and the collector is connected to the call detection circuit 4 via the diode D3 and the resistors R4 and R4. It is connected to a reference potential point via R6 and R7. The base of the lighting drive element Q3 is connected to the connection point of the resistors R6 and R7, and the resistors R4 and R6
Is connected to the collector of the blinking drive element Q2 via the diode D5, the base is connected to the blinking circuit 6, and the emitter is connected to the reference potential point.

The intercom slave 2a includes a call holding circuit 8a,
A call switch 9a, a capacitor C1, and a speaker 10 are provided. The capacitor C1 and the speaker 10 connected in series are connected in parallel with the call holding circuit 8a, and the call switch 9a is connected to the call holding circuit 8a.

In the above description, the configuration of the intercom master unit corresponding to one intercom slave unit 2a has been described, but the other interphone slave unit 2b has the same configuration. Therefore, description of the other intercom slave 2b is omitted.

In the loudspeaker-type intercom apparatus constructed as described above, in the standby state of the intercom master unit 1, no current flows through the call holding circuit 8a and the capacitor C1 unless the call switch 9a of the intercom slave unit 2a is pressed. The light-emitting diode LED1 of the intercom master unit 1 is off.

In this state, when the call switch 9a of the intercom slave unit 2a is pressed, the power supply circuit 3 of the intercom master unit 1 supplies the diodes D1, D2, D4 and the make contact m1 of the first circuit 7a of the tuning switch 7. Then, a current flows to the call holding circuit 8a of the intercom slave unit 2a via the connection line L1 via the common contact c1, and the call holding circuit 8a is held.
Due to the holding operation of the call holding circuit 8a, the intercom slave unit is connected from the power supply circuit 3 via the resistors R1, R2, the diode D4, the make contact m1 of the first circuit 7a of the tuning switch 7 and the connection line L1 via the common contact c1. 2a call holding circuit 8a
Current continues to flow. As a result, the lighting control element Q1 of the intercom master unit 1 operates, and as a result, the bias current of the lighting drive element Q3 flows from the power supply circuit 3. Since the lighting driving element Q3 operates by the bias current of the lighting driving element Q3, the light emitting diode LED1, the resistor R3,
Since current flows through the common contact c2, the make contact m2, and the lighting drive element Q3 of the second circuit 7b of the tuning switch 7, and the blinking drive element Q2 operates intermittently by the blinking circuit 6, the lighting drive from the power supply circuit 3 is performed. The bias current of the element Q3 is interrupted by the blinking drive element Q2, and the light emitting diode LED1 blinks.

Further, from the power supply circuit 3, the lighting drive element Q3
And a current is passed to the call detection circuit 4 via the diode D3, so that the call detection circuit 4 detects a call and generates a ringing tone.

In this way, the intercom base unit 1 can know the call from the intercom slave unit 2a by the blinking of the light emitting diode LED1 and the ringing sound.

Next, when the movable element 7c of the tuning switch 7 of the intercom master unit 1 is slid, the common contact c1 -make contact m1 of the first circuit 7a and the common contact c2 -make contact m2 of the second circuit 7b are changed. The gap is opened and the first circuit 7a
Common contact c1-break contact b1 and second circuit 7b
Is closed between the common contact c2 and the break contact b2.
When the common contact c1 and the make contact m1 of the first circuit 7a are opened, the power supply to the call holding circuit 8a of the intercom slave unit 2a is cut off, the call holding circuit 8a is reset, and the call detection is stopped by the call detection circuit 4 and the call is not detected. The sound stops. Further, by closing the common contact c1 and the break contact b1 of the first circuit 7a, a path can be established between the transmission / reception circuit 5 of the intercom master unit 1, the capacitor C1 of the intercom slave unit 2a, and the speaker 10, and the interphone master unit 1 intersects. A call to 2a becomes possible.

Opening of the common contact c2-make contact m2 of the second circuit 7b and the common contact c2-break contact b2
Is closed, the light emitting diode LED1 is directly connected to the reference potential point, so that the light emitting diode LED1 changes from blinking to lighting.

At this time, when there is a call from the other handset 2b, the call switch 9b of the handset 2b is pressed in the same manner as when calling the handset 2a, so that the channel selection switch 7 is turned on from the power supply circuit 3. , A current flows to the call holding circuit 8b, and the lighting control element Q1 ', the blinking driving element Q2, and the lighting driving element Q3' operate. Thus, the call detection circuit 4 detects a call, generates a ringing sound, and allows the light emitting diode LED2 to blink by the blinking drive element Q2 and the lighting drive element Q3 '.

When the call from the intercom master unit 1 to the intercom slave unit 2a is completed and the movable element 7c of the tuning switch 7 of the intercom master unit 1 is returned, the common contact c1 and the break contact b1 of the first circuit 7a and the second contact The common contact c2 and the break contact b2 of the two circuits 7b are opened, the light emitting diode LED1 is turned off, and the intercom master unit 1 enters a standby state.

In the above-described embodiment, the case of blinking at the time of calling and lighting at the time of talking has been described. However, if the connection between the break contact b2 and the make contact m2 of the tuning switch of the self-lock interlocking two circuit is reversed, the lighting at the time of calling is performed. Flashes during a call and can be applied in the same manner as the present invention. In the above embodiment, the number of the intercom slaves has been described as two, but the invention is not limited to this.

[0028]

As is apparent from the above description, according to the loudspeaker-type intercom apparatus of the present invention, it is possible to clearly distinguish the state during standby, at the time of a call, and the state at the time of a call, and to receive a call during a call. Time is even more effective. Also, forgetting to return the tuning button can be prevented.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of a loudspeaker-type intercom apparatus according to the present invention.

FIG. 2 is a circuit diagram showing a conventional loudspeaker-type intercom apparatus.

[Explanation of symbols]

 1 ... Interphone master unit 2a, 2b ... Interphone slave unit 3 ... Power supply circuit 5 ... Transmitting and receiving circuit 6 ... Flashing circuit 7 ... Tuning switch of 2 circuits linked to self-lock 7a ... 1st circuit 7b ... 2nd circuit m1, m2 ... Make contact c1, c2 ... common contact b1, b2 ... break contact 7c ... mover 8a ... call holding circuit 10 ... speaker LED1, LED2 ... ······ Light emitting diode L1 ····· Connection line Q3 ···· Lighting drive element Q1 ····· Control element

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-166368 (JP, A) JP 7-42256 (JP, U) JP 7-39158 (JP, U) JP 5 74060 (JP, U) Japanese Utility Model Hei 5-60010 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04M 9/00

Claims (1)

(57) [Claims] A call holding circuit (1) for holding a call to said intercom master via a connection line (L1) to said intercom master (1) having a power supply circuit (3) and a transmission / reception circuit (5). 8a) and a plurality of intercom slave units (2a, 2b ...) in which speakers (10) are connected in parallel.
The intercom master unit is provided with a light emitting diode (LED1,
LED2 ...), make contact (m1), common contact (c1), break contact (b) linked by sliding of the mover (7c)
1) a first circuit (7a), a make contact (m2), a common contact (c2), and a second circuit (7b) having a break contact (b2). 7) is provided corresponding to each of the plurality of intercom slave units, the make contact of the first circuit of the tuning switch is connected to the power supply circuit, the common contact is connected to the connection line, and the break is connected. A contact is connected to the transmission / reception circuit, and the make contact of the second circuit of the tuning switch is connected to the front.
A plurality of intercom handsets are provided for each
Connected to the reference potential point via the lighting drive element (Q3)
The common contact is connected to the power supply circuit via the light emitting diode, the break contact is connected to the reference potential point, and provided in correspondence with the plurality of intercom slaves.
In the standby mode, the lighting drive element is turned off and the
Turn off the light emitting diode, and when calling, the call holding circuit
Is turned on to turn on the lighting drive element.
Control element (Q1) and said point during operation of said control element.
The light emitting die is driven by turning off the lamp driving element intermittently.
A flashing circuit (6) for flashing an audible light, wherein the common switch of the second circuit of the tuning switch during a call is provided .
Contact and break contact light the light emitting diode
A loudspeaker-type intercom device, which is connected so as to cause the loudspeaker to be connected .