JP3390887B2 - Extension communication circuit between telephones accommodating different telephone lines - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extension line communication circuit in which telephone sets accommodating different telephone lines are connected to each other via intercom lines. 2. Description of the Related Art Conventionally, to make a call at a distant place in a home such as a two-family house, a door phone is attached or
It would have been better to newly install a cordless telephone that accommodated two lines. In addition, it is possible to make a call via a telephone office by having two kitchens or two cordless telephones in the case of one. [0003] However, installing a door phone or a two-line cordless telephone is problematic in terms of cost. Calling at home using a telephone line requires a call charge. It was extremely unacceptable. [0004] In order to solve these conventional drawbacks, the configuration of the extension telephone circuit of telephones accommodating different telephone lines according to the present invention is as follows. A telephone control unit, a call power supply, a call detection circuit for detecting a call signal from the door phone, and the telephone control unit receiving a detection output from the call detection circuit or receiving an operation output of a door phone call from the telephone. A doorphone extension circuit including a power supply circuit for supplying a current from the call power supply to the doorphone line, a first doorphone line of a first telephone that accommodates a telephone line and includes the doorphone extension circuit, A telephone connected to a second intercom line of a second telephone equipped with the intercom extension circuit, which accommodates a telephone line different from the line, a call control unit, and a second telephone from the first telephone. A first power supply detection circuit for detecting a current supplied to the first intercom line by an operation of calling a telephone extension, and a control of the call control unit which receives a detection output of the first power supply detection circuit. And a first calling circuit for sending a calling signal to the second intercom line, and detects a current supplied to the second intercom line by an operation of calling the first telephone internally from the second telephone. A doorphone line including a second power supply detection circuit and a second call circuit that sends a call signal to a first doorphone line under the control of the call control unit that receives a detection output of the second power supply detection circuit. And a connection part. FIG. 1 is a circuit diagram of a cordless telephone (hereinafter referred to as a telephone) accommodating different telephone lines according to the present invention, in which an intercom unit is connected to an intercom line.
FIG. 2 is a circuit diagram in which two doorphones are connected to a telephone. 1 and 2 are telephones. The illustration of the telephone line is omitted. 3, 30, 4, and 40 are doorphone extension circuits,
Reference numerals 1 and 41 denote telephone control units, 32 and 42 denote telephone power supplies,
Reference numerals 3, 34, 43 and 44 denote call detection circuits for detecting a call signal from a door phone, and reference numerals 35, 36, 45 and 46 denote call detection circuits 3, 30 (4, 40) by the telephone control unit 31 (41).
A power supply circuit for supplying a current from the telephone power supply by receiving a detection output from the telephone or receiving an operation output of a door phone call from the telephone.
(2) Intercom line accommodated in the intercom extension circuit 3 (4), 53 (54) is the intercom line accommodated in the intercom circuit 31 (41) of the telephone 1 (2), 6 is the intercom line 51. A doorphone line connecting unit for connecting the doorphone line 52, a transformer 61 for connecting the doorphone line 51 and the doorphone line 52, a call control unit 62, and a telephone 63 (64) from the telephone 1 (2) to the telephone 2 (1). A power supply detection circuit that detects the current supplied to the intercom line 51 (52) by the operation of the extension call of the extension. A call control unit 65 receives the detection output of the power supply detection circuit 63 (64). A calling circuit for sending a calling signal to 52 (51), 71 (7)
2) is a door phone connected to the door phone line 53 (54). Reference numeral 73 denotes a door phone connected to the door phone line 51 in FIG. First, a call answering operation between the intercom 71 and the telephone 1 will be described with reference to FIG. When the intercom 71 is operated, the call detection circuit 33 of the intercom extension circuit 30 of the telephone 1 detects this call signal and sends a detection output to the telephone control unit 31. The telephone control unit 31 includes a power supply circuit 35
And a call current is supplied from the call power supply 32 to the doorphone line 53. Here, the intercom 71 and the telephone 1 are in a callable state. The same applies to the case where the telephone 1 is called from the door phone 73, and thus the description is omitted. Next, the intercom 71 is operated by the telephone 1.
The operation for setting the communication state to "communicable" will be described. When the telephone 1 is operated to put the intercom 71 in the talking state, the telephone control unit 31 receiving the operation controls the power supply circuit 35 and supplies the intercom line 53 with the intercom current from the intercom power supply 32. Here, the intercom 71 and the telephone 1 are in a call-enabled state, and the operator of the telephone 1 can remotely listen to the situation around the intercom 71. For example, if one door phone 71 is installed in the infant's room, it is convenient to monitor the state of the infant lying down at a remote place. In the above description, the telephone 1 and the intercom 7
1 has been described, but the telephone 1 and the intercom 73 and the telephone 2 and the intercom 72 also perform the same operation, and a description thereof will be omitted. Next, an extension call between telephones accommodating different telephone lines according to the present invention will be described with reference to FIG. When an operation for calling the telephone 2 from the telephone 1 is performed,
Also in FIG. 1, similarly to the operation of calling the intercom 73 from the telephone 1 in FIG. 2, the telephone control unit 31 controls the power supply circuit 36 and supplies a call current from the call power supply 32 to the intercom line 51. The power supply detection circuit 63 detects the call current supplied to the doorphone line 51 and sends a detection output to the call control unit 62. Then, the calling control unit 62 sends a calling signal to the intercom line 52 to the calling circuit 65. The call signal transmitted to the doorphone line 52 is detected by the call detection circuit 44 of the doorphone extension circuit 4 of the telephone 2. The detection output of the call detection circuit 44 is sent to the telephone control unit 41. The telephone control unit 41 controls the power supply circuit 46 and controls to supply a call current from the call power supply 42 to the intercom line 52. Here the doorphone line 51
Then, the call current is supplied to both the intercom line 52 and the intercom line 52, and the telephone set 1 and the intercom set 2 are set in a communicable state via the intercom line 51, the transformer 61, and the intercom line 52. When the telephone 1 (2) performs a call end operation, the telephone control unit 31 (41) that has detected the call terminates, and the power supply detection circuit 6
Even if the detection output of 3 (64) is received, a malfunction is prevented so as not to generate a call until both telephones return to the standby state. The operation of calling the telephone 1 from the telephone 2 is the same as the operation described above, and thus the description is omitted. In the description of the above embodiment, the doorphone 7
1 to output a call signal to the intercom line 53 and to output a call signal to the intercom line 52 from the call circuit 65 by the call control unit 62 of the intercom unit 6 means that the pair of intercom lines to which the call current is supplied is low. This is to transmit the state when a short circuit occurs with a resistor. The intercom extension circuits 3, 30, 4, and 40 can be miniaturized if they are hybrid ICs. In the above embodiment, since each cordless telephone is provided with a cordless telephone base unit accommodating one telephone line and a plurality of cordless telephone slave units connected to this base unit by a wireless line, a call from an intercom is made. Can be responded to by the master unit or any of the slave units. In addition, the operation of making the door phone communicable can be performed from the master unit or any of the slave units. Therefore, an extension call using a doorphone line can be called from the master unit or any of the slave units, and the master unit or any of the slave units can respond to this call. These operations are achieved by the telephone control unit 31 (41), which has detected an operation from the master unit or the slave unit, controlling the communication path switching circuit. [0012] If it is expected that the cordless telephone will be used in a two-family house in the future, a cordless telephone having the door phone extension circuit according to the present invention should be purchased first as a cordless telephone having the same function. If you purchase, it is possible for both parties to make an extension call using a door phone line. According to the present invention, one telephone is provided with a door phone extension circuit, and the other telephone using a different telephone line is provided with a door phone extension circuit and a door phone line coupling unit, thereby providing a different telephone line. This system is scalable and has an economic effect, because the extension telephone can be used between the telephones accommodating the telephone.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram in which a door phone line connecting portion is connected to a door phone line of cordless telephones accommodating different telephone lines according to the present invention. FIG. 2 A telephone is connected with two door phones. Circuit diagram [Description of reference symbols] 1 Telephone 2 Telephone 3 Door phone extension circuit 4 Door phone extension circuit 31 Control unit 41 Control unit 32 Call power supply 42 Call power supply 34 Call detection circuit 44 Call detection circuit 36 Power supply circuit 46 Power supply circuit 51 Door phone line 52 Door phone Line 6 Doorphone wire coupling unit 61 Transformer 62 Call control unit 63 Feed detection circuit 64 Feed detection circuit 65 Call circuit 66 Call circuit 71 Doorphone 72 Doorphone

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-62761 (JP, A) JP-A-4-346544 (JP, A) JP-A-63-146654 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) H04M 9/00-9/10 H04M 1/00 H04M 1/72-1/738

Claims (1)

(57) Claims 1. A telephone control unit, a call power supply, a call detection circuit for detecting a call signal from a door phone, and the telephone control unit receives a detection output from the call detection circuit. Or, a door phone extension circuit including a power supply circuit for supplying a current from the call power supply to the door phone line by receiving an operation output of a door phone call from a telephone, and a phone line accommodated therein, and the door phone extension circuit is provided. A first intercom line of the first telephone and a telephone line different from the telephone line are accommodated,
A transformer connected between a second doorphone line of a second telephone having the doorphone extension circuit, a call control unit, and an operation of calling the second telephone internally from the first telephone by a first operation. A first power supply detection circuit for detecting a current supplied to the doorphone line, and a second power supply circuit for transmitting a call signal to the second doorphone line under the control of the call control unit receiving the detection output of the first power supply detection circuit. A second power supply detection circuit for detecting a current supplied to the second intercom line by an operation of internally calling the first telephone from the second telephone, and a second power supply circuit. A second call circuit for transmitting a call signal to the first doorphone line under the control of the call control unit which receives a detection output of the detection circuit. Accommodates telephone line Extension speech circuit of the telephone comrades.