JP2000059492A - Telephone set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the problem of a telephone set with a slow transmission timing of a primary reply signal being unable to receive a modem signal with a caller number in the case of branching the telephone set by hooking off the telephone set to bring the telephone set in a state of receiving the caller number, when forming of a DC loop is detected. SOLUTION: When a caller uses a telephone set for dialing a telephone number of a called party, a telephone station causes the polarity of lines to be inverted. When a control circuit 9 detects the polarity inversion, the control circuit 9 checks whether or not a synchronous switch 15 is set to the state of synchronization on. When the synchronous switch 15 is not set to synchronization on, that is, when the synchronous switch 15 of the telephone set of the called party is switched off, the operation is similar to an operation of a conventional telephone set. Specifically, when a CAR is received, a DC loop is formed by off-hooking. Thus, a primary reply signal is sent to the telephone station and a caller number from the telephone station is received and when the telephone station receives the primary reply signal, the telephone station sends a modem signal having a caller number.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telephone apparatus capable of utilizing a caller number notification service for transmitting a caller number from a telephone station before a call signal.

[0002]

2. Description of the Related Art At present, an originating telephone number display service in which a telephone station (subscriber exchange) informs a telephone apparatus of a called party of a telephone number (calling party number) of the telephone apparatus (information receiving terminal) of the calling party. (Pre-communication information notification service) is provided by Nippon Telegraph and Telephone Corporation (NTT).

[0003] This telephone number sending process will be described with reference to the time chart of FIG. By calling the caller's phone,
The central office inverts the polarities of the two telephone lines L1 and L2. Then, the telephone office performs CAR (information receiving terminal activation signal).
(See FIG. 5) to the called party's telephone. This CAR
The telephone of the called party that has received the message goes off-hook and forms a DC loop. At this time, the telephone does not ring even when receiving the CAR.

The telephone station detects the formation of the DC loop as a primary response signal, and sends out a modem signal (information signal) including the calling party number to the telephone of the called party. Upon receiving the modem signal, the telephone of the called party cuts off the DC loop and sends a reception completion signal to the central office. When the telephone station detects the reception completion signal, it determines that the telephone number transmission processing has been completed and transmits a normal call signal (IR) (see FIG. 6). The telephone that has received the call signal notifies the incoming call by ringing. In this way, the called party can be notified of the calling party's telephone number before ringing.

[0005]

However, the method of detecting the CAR and the timing of transmitting the primary response signal after receiving the CAR are not uniform. When the telephone station receives the primary response signal, it stops sending the CAR. For this reason, for example, when a first telephone that detects CAR in one second and a second telephone that detects CAR in two seconds are connected (branched) to the same line, the first telephone is first. Detects the CAR and sends a primary response signal by off-hook, and the telephone station receiving this stops sending the CAR. When the CAR transmission is stopped, the second telephone does not go off-hook and is not ready to receive modem signals. There is a problem that the second telephone cannot display the called number even if a modem signal is sent in this state.

[0006]

SUMMARY OF THE INVENTION The telephone apparatus of the present invention has been made in view of the above circumstances, and includes a DC loop detecting means for detecting the formation of a DC loop of a telephone line connected to a telephone office, and a telephone. A control means is provided which does not go off-hook even when a start signal is received from the station, and goes off-hook when the DC loop detection means detects the formation of a DC loop so that the calling party number can be received.

Further, a switching means for switching between a synchronous ON mode and a synchronous OFF mode, and when the switching means is set to a synchronous OFF mode, when a start signal from a telephone station is received, the switch is turned off and the switching means is turned on. When the mode is set, a control means is provided which does not go off-hook even when receiving the start signal from the central office, and goes off-hook when the DC loop detection means detects the formation of a DC loop.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a main part of the present invention.

A hook switch (1) is connected to a telephone line, and performs line release (release of DC loop) (on-hook) and connection (formation of DC loop) (off-hook). (2) is a 2-wire / 4-wire circuit, which performs 2-wire / 4-wire conversion. (3) is a handset, and a speaker (31)
And a microphone (32).

[0010] (4) is a polarity inversion detection circuit, which is connected to the telephone line and detects the inversion of the polarity of the telephone line.
(5) is an incoming call detection circuit, which is connected to a telephone line and detects an incoming call (call signal) and CAR. (6) is a primary response detection circuit, which detects whether or not a DC loop is formed by detecting the magnitude of a current flowing through a line connected to a telephone line.

Reference numeral (7) denotes a caller number detecting circuit which detects the telephone number (caller number) of the caller from a modem signal input via the 2-wire / 4-wire circuit (2). Output to the control circuit (9). (8) is a DTMF detection circuit,
The DTMF signal input through the 2-wire / 4-wire circuit (2) is detected and output to the control circuit (9).

(9) is a control circuit composed of a microprocessor. The ROM (1) stores an operation program.
Each part is controlled based on 0). (11) is a RAM for storing information necessary for the operation of the control circuit (7).
(12) is a bell, which outputs a ringing tone upon receiving a call.
(13) is a liquid crystal display means for displaying a telephone number, a name, and the like. (14) is an input means for inputting a telephone number and the like. (15) is a synchronous switch, synchronous ON
Perform the setting operation of the mode or the synchronous OFF mode.

Next, the main operation of the present invention will be described. In this embodiment, a synchronous switch (15) is connected to the telephone line of the called party.
And the synchronous switch (1)
The telephone set whose 5) is set to ON is branched. FIG. 2 is a time chart showing the operation in this branch. FIG. 3 is a flowchart showing the operation of the control circuit (9) of the two telephones of the called party.

When the calling party's telephone dials the called party's telephone number, the central office inverts the polarity. When the control circuit (9) detects this polarity inversion (S1), it checks whether or not the synchronization switch (15) is set to synchronization ON (S2).

If the synchronous switch (15) is not set to synchronous ON, that is, if the telephone of the called party whose synchronous switch is OFF in FIG. Specifically, when the CAR is received (Y in S3), a DC loop is formed off-hook. This means that the primary response signal has been transmitted to the telephone station (S4). Further, by this off-hook, it becomes possible to receive the calling party number from the telephone office. The central office, upon receiving the primary response signal, transmits a modem signal having a calling number. The caller number detection circuit (7) detects the caller number from the received modem signal and outputs it to the control circuit (9). When detecting the calling party number (Y in S5), the control circuit (9) closes the DC loop by on-hook (S6). This means that the reception completion signal has been transmitted to the telephone office. Further, the detected calling party number is displayed on the display means (13) (S
7). Upon receiving the reception completion signal, the central office transmits a calling signal. When the control circuit (9) detects the calling signal from the incoming call detection circuit (5) (Y in S8), the control circuit (9) rings the bell (12) to perform incoming call processing (S9).

If the synchronous switch (15) is set to synchronous ON in step S2, that is, if the telephone of the called party whose synchronous switch is ON in FIG. When the primary response signal is detected by the primary response detection circuit (6) (Y in S10), the control circuit (9)
Off-hook (S11). With this off-hook,
The caller number from the telephone office can be received. Then, the process proceeds to step S5, and the display of the calling party number and the incoming call processing are performed by the above-described operation.

In this way, when two telephones are branched, the telephone set to synchronous OFF goes off-hook first, and the telephone set to synchronous ON turns synchronous O
A primary response signal is detected by the off-hook of the telephone set to the FF, and the telephone is off-hook, so that the caller ID can be received. As a result, the calling number of the two devices can be displayed.

When three or more telephones are branched, only one is synchronously turned off, and all other telephones are synchronously turned on.
And Further, the telephone set to be turned off in synchronization may be replaced with a conventional telephone.

[0019]

According to the present invention, when a telephone is branched, the problem that a telephone having a late primary response signal transmission timing cannot receive a modem signal having a calling number is solved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a main part of an embodiment of the present invention.

FIG. 2 is a time chart showing an operation of a calling telephone number display service of the embodiment.

FIG. 3 is a flowchart illustrating an operation of the control circuit according to the embodiment.

FIG. 4 is a time chart showing an operation of a normal calling telephone number display service.

FIG. 5 is a diagram showing a CAR waveform in a calling telephone number display service.

FIG. 6 is a diagram showing a waveform of a call signal in a calling telephone number display service.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hook switch 6 Primary response detection circuit 7 Caller number detection circuit 9 Control circuit 12 Bell 15 Synchronous switch

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K024 CC05 DD04 FF04 GG01 GG05 5K027 AA10 BB04 CC02 FF01 FF22 HH23 JJ01 5K036 AA14 BB11 DD33 EE01 JJ05 JJ13 KK06

Claims (2)

[Claims] 1. A telephone station sends a caller ID notification service activation signal before a call signal, and a telephone device on the called side that has received the activation signal goes off-hook to make a call from the telephone station. A telephone which can use a caller number notification service for sending a caller number to a telephone device on the called side when the central office detects the formation of a DC loop due to the off-hook, and is ready to receive a caller number. An apparatus, comprising: a DC loop detecting means for detecting the formation of a DC loop of a telephone line connected to the telephone station; and A telephone device comprising: a control unit that, when a DC loop is detected by the loop detection unit, goes off-hook to receive the caller ID. 2. A telephone station sends a caller ID notification service activation signal before a call signal, and a telephone device on the called side that has received the activation signal goes off-hook to make a call from the telephone station. A telephone which can use a caller number notification service for sending a caller number to a telephone device on the called side when the central office detects the formation of a DC loop due to the off-hook, and is ready to receive a caller number. An apparatus, comprising: a DC loop detecting means for detecting formation of a DC loop of a telephone line connected to the telephone station; setting means for setting a synchronous ON mode or a synchronous OFF mode; When the synchronous start mode is set, when the start signal is received from the central office, the telephone goes off-hook. When the setting means is set to the synchronous ON mode, the start signal from the central office is set. It is received without off-hook the current Le - telephone apparatus characterized by comprising a control means for off-hook when detecting the formation of a DC loop by flop detection means.