JP2793202B2 - Telephone - Google Patents

Description

Description: Object of the Invention (Industrial Application Field) The present invention relates to a telephone, and more particularly to a telephone which can be connected to a child telephone to form a parent-child telephone system.

(Prior Art and Problems to be Solved by the Related Art) Conventionally, as a parent-child telephone system system for connecting a parent telephone and a child telephone to a telephone line, a system for connecting a parent telephone and a child telephone to a telephone line in a branch form; There is a method of switching connection via a selection circuit. According to these methods, first, in the case of the branch connection method, since the communication path between the parent and the child is always in a connected state, there is a problem that secrecy between the parents and children cannot be maintained. In this method, since it is necessary to supply power to both telephones at the same time in order to make an extension call between the parent and child, there is a problem that the configuration of the switching circuit becomes complicated. Further, since wiring for making a call between the parent and the child is additionally required, there is a problem that the construction is troublesome and the restriction on the system is large.

Accordingly, it is an object of the present invention to provide a telephone which can easily establish a parent-child telephone system by simply connecting child telephones, and in which the system can maintain confidential talk between the parent and child and make an extension call. .

[Configuration of the invention]

(Means for Solving the Problems) According to the present invention, a receiving circuit connected to a telephone line, a power supply circuit for supplying power to a parent telephone and a child telephone, and a line-side contact connected to the telephone line A first switch that has a power-supply-side contact connected to the power supply circuit, a movable contact that is connected to one of these contacts, and that is switched to the power-supply-side contact at the time of restoration; and a first changeover switch. A dial circuit connected to the movable contacts of the first and second switches, and a dial circuit for turning on and off the communication path; a communication circuit connected to the first switch via the dial circuit; and a movable circuit of the first switch. A signal receiver provided in parallel with the first changeover switch, and a line-side contact connected to the telephone line, a power-supply-side contact connected to the power-supply circuit; A second changeover switch that has a movable contact that performs switching and is switched to a power-supply-side contact at the time of restoration; a second terminal that is connected to a movable contact of the second second switch and that connects a second terminal; Via a terminal or another terminal, a ringing signal generating circuit for supplying a ringing sound to the slave phone, and a control unit for controlling the first and second changeover switches, the ringing signal generating circuit and the dial circuit, The control unit, when an incoming call from an outside line is detected by the incoming call circuit, switches a movable contact of the first changeover switch to a line side contact, and further turns on the dial circuit by an off-hook of the master telephone. Form a communication path between the telephone line and the communication circuit via the first changeover switch, and the control unit controls an off-line for calling the master telephone. When the dialing circuit is detected, the dial circuit is turned on, and power is supplied from the power supply circuit to the communication circuit via the dial circuit via a power supply contact of the first changeover switch. When the special number for an internal call is input, the first changeover switch is connected to the line side contact to control the communication with the external line when the special number for the external call is input. Generating a calling signal from the calling signal generating circuit to call the slave telephone, and by feeding the slave telephone off-hook, a feeding contact of the second switch, a feeding contact and a movable contact of the first switch, and the dial The control unit controls an extension call via a circuit, and the control unit, when the sub-telephone makes a call, supplies a special number input by the sub-telephone to a power supply side connection of the second changeover switch. And when the special number received by the signal receiver via the power-supply-side contact and the movable contact of the first changeover switch is a special number for outside-line communication, switches the second changeover switch to a line-side contact. Connecting the sub-telephone to the telephone line, while turning on the dial circuit in the case of an extension special number, and connecting the sub-telephone and the telephone circuit of the parent telephone. provide.

It is desirable that an existing MF receiver be used for the call request receiving circuit, and that a call request from a slave telephone be made using an MF signal.

(Operation) According to such a configuration, a parent-child telephone system can be assembled only by connecting a child telephone to the telephone of the present invention. In this system, when a dial number for requesting an outside line is input from the keypad of the parent telephone,
Only the parent telephone is connected to the telephone line by the first switching circuit. Also, when an external line call is requested from the child telephone, only the child telephone is connected to the telephone line by the second switching circuit. Therefore, when one of the telephones is on the outside line, the other is disconnected from the telephone line, so that mutual confidentiality can be maintained. Further, when an extension call is requested from the parent or child telephone, both telephones are connected to the power supply circuit in common by the first and second switching circuits. The telephone is driven by the electric power of the telephone.

(Embodiment) FIG. 1 shows an embodiment of a telephone according to the present invention.

The telephone 1 according to the present invention is configured as an answering machine. Hereinafter, the configuration will be described. A receiving circuit 3 is connected to a telephone line 2. When the incoming call circuit 3 detects an incoming signal from the telephone line 2, it makes a ringing tone through a speaker (not shown) and outputs an incoming call detection signal 3a to a microcomputer 4 for controlling the entire telephone.

The telephone line 2 also includes, via a rectifying bridge 5, a holding circuit 6 that sends out a holding tone according to a command from the microcomputer 4, an MF receiver 7 that receives an MF signal and sends a decoding result to the microcomputer 4, One fixed contact 8a of the first changeover switch 8 controlled by the microcomputer 4 and one fixed tangent 9a of the second changeover switch 9 also controlled by the microcomputer 4 are connected. The other fixed contacts 8b, 9b of the first and second changeover switches 8, 9 are commonly connected and connected to the output of the power supply circuit 10. The power supply circuit 10 sends a power supply signal 10 a to the microcomputer 4 according to the number of telephones that are supplying power. A DC blocking capacitor 11 is inserted between the rectifier bridge 5 and the MF receiver 7.

The MF receiver 7 is connected to the movable contact 8c of the first changeover switch 8 via the DC blocking capacitor 12, and the telephone call circuit 14 is connected via the dial circuit 13. Answering machine with various circuits 15
Is connected to a dial tone generation circuit 15a. The handset 16 and the MF signal generation circuit 15b in the answering machine circuit 15 are connected to the communication circuit 14.

A speaker 17 is connected to a voice recording / reproducing circuit (not shown) in the answering machine circuit 15. In the answering machine circuit 15, in addition to the dial tone generating circuit 15a, the MF signal generating circuit 15b and the voice recording / reproducing circuit described above, a calling signal generating circuit 15c for generating a calling signal, and switches 8 and 9 are driven. A not-shown relay coil and the like are also mounted.

The telephone 1 is connected to a sub telephone 18 composed of a standard telephone and a sub telephone 18 via a four-core moshler cord 20.
The sounder 19 installed near is connected. The sounder 19 is connected to a call signal generating circuit 15c in the answering machine circuit 15, and the sub telephone 18 is connected to the movable contact 9c of the second changeover switch 9. This child phone 18
Has a function of making a dial call using an MF signal.

The microcomputer 4 controls the hold circuit 6, the first and second changeover switches 8, 9, the dial circuit 13, the answering machine circuit 15, etc., and as described above, the incoming call detection signal 3a from the incoming call circuit 3 , The feed data from the MF receiver 7 and the power supply signal 10 a from the power supply circuit 10, and a hook switch 21 linked to the operation of the handset 16.
And a key input signal from the dial keypad 22 are also input.

Further, a power supply circuit 23 for supplying a constant voltage V _CC to each of the components described above is provided, and operates by receiving power supply from a commercial AC power supply.

Next, the operation of the parent-child telephone system including the telephone 1 and the child telephone 18 will be described.

Incoming call from outside line The incoming signal from the telephone line 2 is detected by the incoming circuit 3, a ringing tone sounds and an incoming call detection signal 3 a is transmitted to the microcomputer 4. The microcomputer 4 sends a control signal to the answering machine circuit 15, drives the relay coil in the answering machine circuit 15, and connects the movable contact 8c of the first changeover switch 8 to the contact 8a on the telephone line side.
At this time, the second switch 9 is connected to the power supply circuit side contact 9b.

Subsequently, in the case of the automatic answering mode, the microcomputer 4 closes the dial circuit 13 to form a communicable state, and then drives a voice recording / reproducing circuit (not shown) in the answering machine circuit 15 to answer. A message is sent to the telephone line 2, and thereafter, the answering machine circuit 15 is controlled in accordance with the result of decoding the MF signal from the other party inputted from the telephone line 2 by the MF receiver 7 and a series of answering service. Execute On the other hand, when the normal telephone mode is set, the microcomputer 4 connects the first change-over switch 8 to the telephone line side contact 8a as described above, and then controls the handset 16 by the hook signal from the hook switch 21. When the off-hook is known, the dial circuit 13 is turned on and the telephone line 2
And the handset 16 is closed.

Outgoing Call from Master Telephone 1 In a normal telephone mode, when the handset 16 goes off-hook, a hook signal is issued from the hook switch 21 and the microcomputer 4 turns on the dial circuit 13. At this time, the first switch 8 is connected to the power supply circuit side contact 8b as shown by a solid line, and the power from the power supply circuit 10 drives the communication circuit 14 and the handset 16.
At this time, the second switch 9 is connected to the power supply circuit side contact 9b. Simultaneously with the turning on of the dial circuit 13, the microcomputer 4 causes the dial tone generating circuit 15a in the answering machine circuit 15 to send out the dial tone.
Through to the handset 16.

Next, the dial number is input by the keypad 22. At this time, if an outside line call is desired, a special number (for example, “0”) to that effect is input first. By inputting this special number, the microcomputer 4 connects the first changeover switch 8 to the line side contact 8a. The dial number entered thereafter is sent to the MF signal generation circuit 15 in the answering machine circuit 15.
b is transmitted to the telephone line 2 as an MF signal. Thereafter, outside line communication is performed in the same manner as a normal telephone.

On the other hand, when the input dial from the keypad 22 is a special number (for example, "9") for which an extension call is desired, the microcomputer 4 causes the ringer 19 to ring the sounder 19 by the calling signal generation circuit 15c in the answering machine circuit 15. The sub telephone 18 is called. When the mobile phone 18 is turned off-hook in response to this call, power supply from the power supply circuit 10 to the mobile phone 18 is started, and the power supply circuit 10 detects an increase in load due to this and sends a power supply signal 10a to the microcomputer 4. send. The microcomputer 4 stops the sounding of the sounder 19 when the off-hook of the slave phone 18 is known from the power supply signal 10a. Thereafter, an extension call is made on the route of the slave telephone set 18, the second changeover switch 9, the first changeover switch 8, the dial circuit 13, the call circuit 14, and the handset 16.

Transmission from slave phone 18 When the slave phone 18 is off-hook, a power supply signal 10 a is sent from the power supply circuit 10 to the micro computer 4. Subsequently, the dial number is transmitted as an MF signal from the slave telephone set 18, input to the MF receiver 7, converted into digital dial data, and input to the microcomputer 4.

If the first dial data is a special number (for example, "0") for which an outside line call is desired, the microcomputer 4 connects the second changeover switch 9 to the line side contact 9a and sets the slave telephone.
Connect 18 to telephone line 2. As a result, the subsequent MF dial signal from the sub telephone 18 is transmitted to the telephone line 2.
That is, an outside line is transmitted from the slave telephone set 18.

On the other hand, if the first dial data is a special number (for example, "9") for which an extension call is desired, the microcomputer 4 causes the incoming call circuit 3 to output a ringing tone. Is closed. As a result, an extension call between the parent and child telephones can be made.

In each of the above cases, when the DC disconnection signal (flash signal) is detected during a call, the microcomputer 4 activates the holding circuit 6 to hold the signal. Release of the hold is performed by detecting a change in the DC voltage of the telephone line by a circuit (not shown).

FIG. 2 shows another embodiment of the present invention. The telephone 24 is characterized in that a bell signal generating circuit 15d is provided in the answering machine circuit 15, and the output thereof is connected to the slave telephone 18 via a switch 25 controlled by the microcomputer 4,
In the case of calling page 18, a bell signal is output from the bell signal generating circuit 15d, and the bell signal is intermittently sent to the slave telephone set 18 by a switch 25 at a predetermined cycle. Such a configuration has an advantage that a sounder is not required and the configuration of the system is simplified.

By the way, in the embodiment described above, the master telephone is configured as an answering machine, but it goes without saying that the present invention is not limited to the answering machine. However, in the case of an answering machine, since the MF receiving function and the automatic answering connection function are already built in, there is an advantage that the master telephone of the present invention can be easily configured using these functions.

Further, in the above embodiment, the MF dial signal from the slave telephone is used as the call request signal. However, the change of the power supply signal 10a caused by turning on / off the DC loop of the slave telephone is used as the external call request signal of the slave telephone. It is also possible to use as.

〔The invention's effect〕

As described above, according to the present invention, a power supply circuit is provided in a telephone, and a switching circuit for selectively connecting a sub-telephone and its own telephone to a telephone line and a power supply circuit is provided. Since control is performed in response to a call request from a telephone, a parent-child telephone system can be easily assembled simply by connecting a child telephone to the telephone according to the present invention, and mutual confidentiality can be maintained and extension calls can be easily realized.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of a telephone according to the present invention,
FIG. 2 is a block diagram of another embodiment of the present invention. 1,24 telephone set 2 telephone line 3 ring circuit 4
... Microcomputer, 7 MF receiver, 8 first switch, 9 second switch, 10 power supply circuit, 13 dial circuit, 14 telephone conversation circuit, 15 answering machine Telephone circuit, 15c ... Paging signal generation circuit, 15d ... Bell signal generation circuit, 16 ... Handset, 18 ... Subphone, 19 ... Sounder, 21 ... Hook switch, 22 ... Keypad, 25 ... switch.

Claims (1)

(57) [Claims] 1. A receiving circuit connected to a telephone line, a power supply circuit for supplying power to a parent telephone and a child telephone, a line-side contact connected to the telephone line, and a power supply side connected to the power supply circuit. A first switch having a contact and a movable contact for switching to one of these contacts, and being switched to a power supply contact at the time of restoration; and a first switch connected to the movable contact of the first switch to establish a communication path. A dial circuit for turning on and off, a call circuit connected to the first changeover switch via the dial circuit, a signal receiver connected to a movable contact of the first changeover switch, A line-side contact connected to the telephone line, a power-supply-side contact connected to the power-supply circuit, and a movable contact for switching to one of these contacts. A second switch that is switched to a contact, a second terminal connected to the movable contact of the second switch, and a second terminal for connecting a second telephone; the second terminal or another terminal; A ringing signal generating circuit that supplies a ringing tone to the first and second switches, a control unit that controls the ringing signal generating circuit and the dial circuit, and the control unit is configured to control the ringing circuit from an outside line. When an incoming call is detected, the movable contact of the first changeover switch is switched to a line-side contact, and the dial circuit is turned on by an off-hook of the master telephone, whereby the first switch is turned on.
Forming a communication path between the telephone line and the communication circuit via a changeover switch, and, when the control unit detects an off-hook for calling the master telephone, turns on the dial circuit; First
Power is supplied from the power supply circuit to the communication circuit via the dial circuit via the power supply side contact of the changeover switch. Further, when the special number for outside line communication is input, the control unit Is switched to the line side contact to perform a call with an outside line. On the other hand, when a special number for an extension call is inputted, a calling signal is generated from the calling signal generating circuit and the slave telephone is generated. And performing a control to perform an extension call via the power supply side contact of the second changeover switch, the power supply side contact and the movable contact of the first changeover switch by the off-hook of the slave telephone, and the dial circuit, and The unit, when the sub-telephone makes a call, transmits the special number input by the sub-telephone via the power supply side contact of the second changeover switch, the power supply side contact of the first changeover switch, and the movable contact. If the received special number is an external line special number, the second changeover switch is switched to a line side contact, and the slave telephone is connected to the telephone line. In the case of a telephone special number, the telephone circuit turns on the dial circuit and connects the child telephone and the telephone circuit of the parent telephone.