JPH08242277A - Telephone set - Google Patents

Abstract

PURPOSE: To enable the end-to-end service by automatically switching a dial mode to the DTMF mode based on the polarity of the DC power source of a telephone line. CONSTITUTION: The polarity inversion of a power source voltage VL between telephone lines L1 and L2 when a dial originating state is shifted to a speech state is detected by a polarity detecting means 6 and the inversion information PO of one-shot pulse is supplied to a switching means 7. A control means 8 supplies mode switching signals ST at the level H and mode switching signals S1 and S2 at the level L to a dial circuit 4 based on the PO. With a dial mode switching switch 5, the DP dial mode is released and the mode is set to the DTMF mode. A setting means 9 sends a reset signal PR to the control means 8 when a power source RO is turned on at the time of off-hook and stops a signal output means. Thus, the dial mode in a speech state is automatically switched to the DTMF dial mode.

Description

Detailed Description of the Invention

[0001]

This invention relates to dial pulse (D
P) is connected to the analog telephone line and D is called after the called party answers.
The present invention relates to a telephone that can use an end-to-end service by switching to a TMF (PB) signal.

[0002]

2. Description of the Related Art Dial selection signals (dial signals) used in telephones such as fashion telephones, answering machines, and cordless telephones connected to analog telephone lines depend on the type of exchange at the central office to which the telephone is connected. DP signal (dial pulse) that generates a pulse corresponding to the dial number by connecting and disconnecting the station power (48V) and 2
DTMF (Dual which makes frequency signal correspond to dial number)
There are two types of Tone Multi Frequency signals.

The DP (dial pulse) signal is mainly used as a dial number and connects a calling party (sending side) and a called party (receiving side) through an exchange, while DTMF is used.
Signals are used not only as dial numbers, but also for seat reservations for Shinkansen, various reservations for tickets, private supplementary schools, pager fixed phrase display, remote control operation for answering machines, home banking, home trading, etc. Used to receive services.

In the conventional telephone, a dial mode selector switch is provided, and 10 PPS / 20 PPS (PP) corresponding to a telephone line (central office switch) to which a single telephone is connected.
It is known that two types of DP dials of S: Pulse Per Second) and DTMF dials can be manually switched.

3 and 4 are external views of conventional telephones. FIG. 3 shows an external view of the rear surface of the telephone body, and FIG. 4 shows an external view of the telephone body and the child device. In FIG. 3, a conventional telephone 50 has a dial mode selector switch 52 provided on the back surface of a telephone case 51. The dial mode changeover switch 52 is adapted to allow the telephone 50 to be connected to either DP or DTMF telephone line (exchange), and is composed of, for example, a slide switch or a DIP switch, and is displayed on the switch by a manual operation. 1
The dial mode of 0PPS, 20PPS and tone (DTMF) is switched.

Assuming that the telephone 50 is connected to the DP telephone line (exchange) and the end-to-end service (for example, Shinkansen seat reservation) is received by the DTMF signal, the dial mode switch 52 is set to 10 PPS or 2.
The DP mode of 0PPS is set, and the dial number (telephone number) of the service providing destination is dialed.

When the service provider responds, the dial mode selector switch 52 is manually operated to give a tone (DT).
After switching to MF) and operating the dial button according to the voice guidance of the service providing destination to send out the DTMF signal, the seat reservation number is notified by voice. In preparation for the next dial call, set the dial mode switch 52 to the original DP
The mode (10 PPS or 20 PPS) is returned to and the series of operations is completed. In addition, dial mode switch 5
There is also a telephone in which 2 is provided on the bottom surface of the telephone case 51.

Further, like the telephone main body 53 and the slave unit 55 shown in FIG. 4, the dial buttons 54 and 56 are provided with tone buttons 54A and 56A for switching the dial mode from the DP mode to the DTMF mode. There is also known a telephone configured to operate the tone buttons 54A and 56A to switch from the DP dial mode to the DTMF dial mode without operating the dial mode selector switch 52.

Dial number 1 in DP dial mode
A 10-key dial button corresponding to (1 pulse) to 0 (10 pulses) is required. On the other hand, in the DTMF dial mode, in addition to the 10 keys with dial numbers 1 to 0, two function keys * (star) and # (Scare) added 12
Since the key dial buttons are prepared, the two function keys can be used as function buttons other than dial in the DP dial mode.

The tone buttons 54A and 56A are manually operated, for example, by using the function key * to switch the communication state after the DP dial is made to switch from the DP dial mode to the DTMF dial mode. It is configured to be used as an end-to-end service as a function key button. It is also known that the tone button is provided independently of the dial button.

[0011]

The dial mode changeover switch 52 is switched to change from the DP dial mode to DTMF.
In the conventional telephone that switches to the dial mode, it is necessary to switch the dial mode selector switch 52 to the DTMF dial mode in the call state, and to switch to the DP dial mode after the call ends. However, the operability is poor, and there is a troublesome problem.

Further, a telephone main body 53 or a handset 55 in which the function key * button of the dial button 54 or 56 is also used as the tone button 54A or 56A, or a telephone provided with the tone button independently of the dial button is
If the two-end service is frequently used, the operation of the tone button may be forgotten or the operation may be troublesome.

The present invention has been made to solve such a problem, and its purpose is to provide a DTMF when a call state is established.
It is to provide a highly convenient telephone that automatically switches to a mode and can use end-to-end services.

[0014]

In order to solve the above-mentioned problems, a telephone according to the present invention is based on polarity detecting means for detecting the polarity of a DC power source supplied from a telephone line and information from this polarity detecting means. It is characterized in that a switching means for changing the selection signal of the dial unit is provided.

Further, the switching means of the telephone according to the present invention is characterized by including setting means for initializing the selection signal when the telephone line is closed.

[0016]

The telephone according to the present invention comprises the polarity detecting means for detecting the polarity of the DC power source supplied from the telephone line, and the switching means for changing the selection signal of the dial unit based on the information from the polarity detecting means. Therefore, the dial mode in the call state can be automatically switched to the DTMF dial mode.

Further, in the telephone according to the present invention, the switching means is provided with the setting means for initializing the selection signal when the telephone line is closed. Therefore, the telephone is always set to the DP dial mode when dialing. be able to.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of the essential parts of a telephone according to the present invention. In FIG. 1, the telephone set 1 includes a connection terminal L1 and a connection terminal L1 to the analog telephone line 10 and a connection terminal L1.
Polarity matching diode bridge DB that supplies the telephone voltage V _TEL to each part of the telephone 1 by always matching the polarities of the station power supply voltage V _L supplied between the switch and the switch L2.
A telephone circuit 2, a handset including a transmitter unit T and a receiver unit R, and a dial circuit 4 constituting a dial unit.

The hook switch HS is composed of, for example, an electronic switch such as an NPN transistor or FET (field effect transistor), and a control signal V _H supplied from the dial circuit 4 with the handset lifted (off hook).
Then, the analog telephone line 10 is captured by turning on the call circuit 2 by supplying DC power (telephone voltage V _TEL ).

The call circuit 2 is, for example, a call IC including a transmitter amplifier, a receiver amplifier, a side tone circuit, a DTMF output circuit, and the like.
The voice signal is transmitted from the transmitter unit T to the analog telephone line 10 and the voice signal from the analog telephone line 10 is converted into voice by the handset unit R to listen to the call.

The dial circuit 4 includes a DP pulse and a DT.
It is composed of a dial IC that generates MF signals, and has 12 dial buttons (DP dial is 0-9, 10 keys, DT
The MF dial generates a selection signal corresponding to the dial mode (10 PPS, 20 PPS, tone) set by the dial mode changeover switch 5 based on the key information S _K from the 12 keys (* and # added).

For example, when the dial mode changeover switch 5 is set to 10 PPS or 20 PPS, the dial circuit 3 is operated to provide the hook circuit HS with the number of pulses V _DP corresponding to the key figure from the dial circuit 4.

Further, when the dial mode changeover switch 5 is set to tone, the dial circuit 3 is operated to output from the dial circuit 4 the two-frequency mixed DTMF signal V _MF.
Is transmitted to the analog telephone line 10 via the DTMF output circuit of the communication circuit 2 and the transmission amplifier.

The station power supply voltage V _L is formed so that the polarity is reversed when the called party responds from the state where the telephone 1 is off-hook and dialed, and the polarity is restored when the call ends. The central office uses this polarity reversal as billing information to manage call charges.

FIG. 2 shows a polarity state diagram of the station power supply. (A) figure shows dialing state, (b) figure shows calling state,
FIG. 3C shows a waveform diagram of the station power supply voltage V _LO when the dial transmission state is changed to the call state. The station power supply voltage V _L indicates the voltage at the terminal 1 of the telephone, the station power supply voltage V _LO indicates the voltage at the terminal of the _central office switch 11, and the station power supply voltage V _L indicates the voltage of the station power supply voltage V _LO and the subscriber line. It is the difference in voltage drop.

In the dial transmission state (including the standby state) shown in FIG. 3A, the station power supply voltage V _LO of the _central office 11 is positive (+) polarity on the connection terminal L1 side of the telephone 1 and negative (-) polarity on the L2 side. It is set to be
V) is plus (+) and -48V is minus (-). This state continues until the called party answers, and the call charge is not charged.

At the same time as the called party responds to the call from the state shown in FIG. 3A, the call state shown in FIG. 2B is entered, the polarity of the station power supply voltage V _LO of the central office switch 11 is reversed, and the connection terminal L of the telephone 1 is connected.
The 1 side is set to the minus (-) polarity and the L2 side is set to the plus (+) polarity. This state continues until the call ends,
Call charges will be charged during this period.

As shown in FIG. 3C, when the dial transmission state is changed to the talking state, the station power supply voltage V _LO is -48V to + 48V when the connection terminal L1 side of the telephone 1 is used as a reference.
When the call state shifts to the standby state, the station power supply voltage V _LO changes abruptly from + 48V to -48V.

In this way, the station power supply voltage V _LO supplied from the exchange 11 is reversed in polarity when the telephone 1 dials out and the called party responds and enters the talking state, so this polarity inversion is detected. Then, it can be used for DTMF dial mode switching for receiving end-to-end service in a call state.

In FIG. 1, the polarity detection means 6 is connected to both ends of the station power supply voltage V _L between the connection terminals L1 and L2 and the polarity matching diode bridge DB, and the station power supply voltage at the time of shifting from the dial transmission state to the call state. The polarity reversal of V _L is detected and the polarity reversal information P _O is provided to the switching means 7.

The polarity detection means 6 comprises a photocoupler such as a photodiode or phototransistor and a detection circuit in which two series circuits of resistors (high resistance value) are arranged in parallel. Inserted between _L , one side series circuit detects a current flowing from the connection terminal L2 side to the connection terminal L1 side (when the polarity of the station power supply voltage _VL is L2 side + polarity, L1 side−polarity), and the other series The polarity of the station power supply voltage _VL is detected by detecting the current flowing from the connection terminal L1 side to the connection terminal L2 side in the circuit (when the polarity of the station power supply voltage _VL is L1 side + polarity, L2 side−polarity). To do. In the photocoupler of the detection circuit, the station power supply voltage V _L that causes polarity reversal and the telephone voltage V _TEL that drives the polarity detection means 6 that detects this polarity reversal are different, so that the two power supplies are separated. To use.

Further, the polarity detecting means 6 is provided with a judging means such as a light receiving portion of a photodiode, a logical operation circuit, a one-shot pulse generating circuit, etc., which is operated by a power source E _O, which has stepped down the telephone voltage V _TEL whose polarity is always constant. , And supplies polarity inversion information P _O to the switching means 7 based on the polarity inversion signal (current inversion information of the photodiode) from the power supply E _O and the detection circuit. For example, when the power source E _O has a predetermined value and the polarity inversion signal is received, one shot pulse having a short pulse width is output as the polarity inversion information P _O.

The switching means 7 comprises a control means 8 and a setting means 9.
The control means 8 outputs the mode switching signals S _T , S ₁ and S ₂ to the dial circuit 4 based on the polarity reversal information P _O provided from the polarity detecting means 6, and the dial mode switching switch at the time of transition to the call state. The DP dial mode (10PPS or 20PPS) set in step 5 is released to set the DTMF mode (tone), and the setting means 9 sets the D mode set by the dial mode changeover switch 5 during off-hook.
It is configured to be in the P dial mode.

The control means 8, for example, a state storing means is constituted by a memory such as a flip-flop, a ROM, and a signal output unit, the state storage means in advance based on the polarity inversion information P _O provided by the polarity detection means 6 The set mode switching signals S _T , S ₁ , S ₂ are supplied to the dial circuit 4.

For example, when the polarity reversal information P _O is supplied to the control means 8, the output signal of the state storage means composed of a flip-flop changes, and the signal output means changes to the H level (power source E based on this output signal). _O ) mode switching signals S _T , L
The level (GND potential) mode switching signals S ₁ and S ₂ are output.

Further, when the polarity reversal information P _O is supplied to the control means 8, the mode switching data S _T and the mode switching data S ₁ and S ₂ which are preset in the state storage means constituted by a memory such as a ROM are read out. , A mode switching signal S _{T of} H level (power supply E _O ) and a mode switching signal S ₁ , S of L level (GND potential) from a signal output means composed of a buffer, for example.
₂ may be supplied to the dial circuit 4.

Further, the control means 8 is constructed so as to make the signal output means inoperative based on the reset signal P _R from the setting means 9 to raise the output impedance of the signal output means. Due to the high output impedance of the signal output means, the switching means 7 is electrically disconnected from the dial circuit 4, and the dial mode is the DP dial mode (10PPS) set by the dial mode selector switch 5.
Or 20PPS).

The setting means 9 is composed of a power-on reset circuit. When the telephone voltage V _TEL is supplied at the time of off-hook and the power supply E _O rises, the reset signal P _R is generated and supplied to the control means 8 to output the signal output means. Is controlled so as not to operate.

In this embodiment, an example in which the present invention is applied to a telephone having a basic function has been described, but the present invention can be similarly applied to a multifunction telephone such as an answering machine or a cordless telephone.

[0040]

As described above, in the telephone according to the present invention, the polarity detecting means for detecting the polarity of the DC power source supplied from the telephone line and the dial unit selection based on the information from the polarity detecting means. Equipped with switching means for changing the signal, the dial mode in the call state is automatically DTMF
Since it is possible to switch to the dial mode, it is possible to receive the end-to-end service without requiring a special operation even if it is connected to a DP-compatible telephone line.

Further, in the telephone according to the present invention, the switching means is provided with setting means for initializing the selection signal when the telephone line is closed, and is always set in the DP dial mode when dialing. Since it is possible, DP dial mode and DTMF are automatically set according to the operating status of the telephone.
The mode can be switched.

Therefore, even if the line is connected to the DP line, the dial mode is automatically switched to the DTMF mode.
A highly convenient telephone that can receive a two-end service can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a telephone according to the present invention.

[Figure 2] Polarity diagram of station power supply

[Figure 3] Rear view of the phone body

[Fig. 4] Appearance diagram of the main unit and cordless handset

[Explanation of symbols]

1 ... Telephone, 2 ... Communication circuit, 3 ... Dial button, 4 ...
Dial circuit, 5 ... Dial mode selector switch, 6 ...
Polarity detection means, 7 ... switching means, 8 ... control means, 9 ... setting means, 10 ... telephone line, 11 ... central office switch, L1, L2 ...
Connection terminal, DB ... Polarity matching diode bridge, _EO ...
Power supply, HS ... Hook switch, S _K ... Key information, P _O ... Polarity inversion information, P _R ... Reset signal, R ... Receiver unit, S _T , S ₁ , S ₂ ... Mode switching signal, T ... Transmitter unit , V _DP ... pulse, V _H ... control signal, _VL , V _LO ... station power supply voltage, V _MF ... DTMF signal, V _TEL ... telephone voltage.

Claims (2)

[Claims] 1. A polarity for detecting the polarity of a direct-current power supply supplied from a telephone line in a telephone which can switch to a PB signal and can be used for end-to-end service after being connected to a called party by a dial pulse selection signal. A telephone having a detecting means and a switching means for changing the selection signal of the dial unit based on the information from the polarity detecting means. 2. The telephone according to claim 1, wherein the switching unit includes a setting unit that initializes the selection signal when the telephone line is closed.