JPH0537612A - Telephone system - Google Patents

Abstract

PURPOSE:To avoid the telephone system from reaching the disable state making calling from other terminal equipment impossible even when a handset of the telephone system is lifted off from a main body and the telephone set is left hooked-off. CONSTITUTION:A line changeover section 8 is interposed between a telephone line and a hook switch, the state of the hook switch 1 and the presence of a busy tone of the telephone line are detected respectively, and when the state of hook-off and the busy tone are both detected, the telephone line is disconnected from the hook switch and connected to a tone ringer, and when the on-hook state is detected, the telephone line is connected to the hook switch. When the telephone system is kept hooked off, the interruption processing to open the telephone line in terms of DC is implemented and the tone ringer is connected to the telephone line subjected to interrupt processing to form the same incoming call standby state as if the state were the regular on-hook state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telephone device used by connecting to a general subscriber telephone network or a private telephone network.

[0002]

2. Description of the Related Art As shown in FIG. 3, a conventional device of this type includes a hook switch 1, a tone ringer 2, a communication circuit 3, a handset 4, a dial transmission circuit 5, and a numeric keypad 6 for dial operation. And the telephone line L is connected to the call circuit 3 when the hook switch 1 which is interlocked with the pick-up operation of the handset 4 is in the off-hook state and is closed in a direct current manner, and the hook switch 1 is in the on-hook state. It has been practiced to disconnect L from the communication circuit 3 to open it in a direct current manner and connect it to the tone ringer 2 (see, for example, Japanese Patent Laid-Open Nos. 62-168447 and 59-219039).

[0003]

However, according to such a structure, when the handset of the telephone device is detached from the main body and left in the off-hook state, it cannot be called from another terminal and is in an unusable state. There was a problem that it would end up.

The above-mentioned problems occur for the following reasons. That is, the exchange remotely determines the state of the terminal connected to the telephone line depending on whether or not the telephone line is DC-connected. That is, when the telephone device, which is a terminal, is in the on-hook state, it is determined to be in the incoming call waiting state, and when it is in the off-hook state, it is determined to be in the use state, that is, the busy state. Therefore, if the telephone device is left in the off-hook state where the handset is detached, it cannot be called from another terminal and is in an unusable state.

Furthermore, since the telephone device in the off-hook state disconnects the tone ringer from the telephone line, even if the exchange sends a 16 Hz ringing signal, it cannot receive the ringing signal. Therefore, as a warning means that the exchange side can give to the telephone device that has been left in the off-hook state for a certain period of time or longer, there is no choice but to generate a howler sound from the handset of the handset. However, there was a limit to the volume of howler sound emitted from the handset handset, which was far insufficient as a warning to the user.
Further, when the user is absent or away from the telephone device, the above-mentioned howling sound warning is ineffective.

The present invention has been made in view of the above-mentioned problems, and even if the handset of the telephone device is detached from the main body and left in the off-hook state, it cannot be called from another terminal and is in an unusable state. It is an object of the present invention to provide a telephone device that can avoid falling.

[0007]

In order to solve the above problems, the present invention interposes a line switching unit between a telephone line and a hook switch and determines the state of the hook switch and the presence / absence of a busy tone in the telephone line. A configuration in which the telephone line is disconnected from the hook switch and connected to the tone ringer when both the off-hook state and the busy tone are detected, and the telephone line is connected to the hook switch when the on-hook state is detected. It is equipped with.

[0008]

According to the present invention, when the telephone device is left in the off-hook state due to the handset being detached or the like by the above-described configuration, the telephone line is disconnected in the direct current state based on the busy tone emitted from the exchange side. As the processing is performed, a tone ringer is connected to the disconnected telephone line, and the same waiting state for incoming calls as the regular on-hook state is formed.Therefore, the handset of the telephone device is removed from the main unit and off-hook. Even if the terminal is left as it is, it is possible to avoid a situation in which the terminal cannot be called from another terminal and is in an unusable state.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

In the figures, the same reference numerals indicate the same or corresponding parts. FIG. 1 shows a schematic configuration of a telephone device according to an embodiment of the present invention, in which 1 is a hook switch, 2 is a tone ringer which sounds by a call signal of 16 Hz, 3 is a call circuit including a hybrid, and the like.
4 is a handset having a transmitter and a receiver, 5 is a dial transmission circuit, 6 is a numeric keypad for dial operation, 71
Is an off-hook detection circuit for detecting the state of the hook switch 1, 72 is a busy tone detection circuit for detecting a busy tone from the telephone line L, 8 is interposed between the telephone line L and the hook switch 1, and the telephone line L Is a line switching section for switching and connecting to the hook switch 1 or the tone ringer 2, and 9 is a control circuit for controlling the line switching section 8 based on the detection outputs of the detection circuits 71 and 72.

Here, the hook switch 1 operates in conjunction with the picking-up operation of the handset 4. When the handset 4 is detached from the main body of the device, the handset 4 goes off hook and the telephone line L is connected to the telephone circuit 3. The telephone line L is DC-connected by the connection of the call circuit 3. When the handset 4 is returned to the predetermined position of the main body of the device, it goes into an on-hook state, opens the telephone line L in a direct current state, connects the tone ringer 2 to the telephone line L, and forms an incoming call waiting state waiting for a 16 Hz ringing signal. To do.

The control circuit 9 is constructed by using a general-purpose control device, which is a so-called CPU, which is a random logic in which logic gates are combined or is made into a microcircuit, and the above-mentioned two detection circuits 71.
The line switching unit 8 is controlled on the basis of the detected states of the lines 72 and 72. In this control, the telephone line L is switched to the hook switch 1 when both off-hook and busy tone are detected.
The telephone line L is reconnected to the hook switch when an on-hook is detected.

The operation of the telephone device configured as described above will be described below. FIG. 2 is a flow chart showing the outline of the operation of the main part of the telephone device shown in FIG. 1. First, it is checked whether or not the hook switch 2 is in the off-hook state. Here, if it is in the off-hook state, it is checked whether or not a high tone is detected from the telephone line L.

When both the off-hook state and the high tone are detected, the line switching unit 8 is controlled to disconnect the telephone line L from the hook switch 1 and directly connect it to the tone ringer 2. As a result, the telephone line L is connected to the call circuit 3 even if the hook switch 1 is in the off-hook state.
It is separated from and opened to direct current. At this time, the telephone line L in the direct current open state is connected to the tone ringer 2. Therefore, the telephone device at this time is
Even if the hook switch 1 is in the off-hook state, the same incoming call waiting state as that of the regular on-hook state is equivalently formed. As a result, even if the handset 4 of the telephone device is detached from the main body and left in the off-hook state, it is possible to avoid a situation in which the terminal cannot be called by another terminal and is in an unusable state.

When the hook switch 1 is returned to the on-hook state by rehanging the handset 4 after the equivalent incoming call waiting state is formed by the line switching unit 8, the line switching unit 8 returns to the original switching position. As a result, the telephone line L is connected to the hook switch 1 side. As a result, the telephone device can return to the original on-hook state.

[0016]

As is apparent from the above description, according to the present invention, a line switching unit is interposed between a telephone line and a hook switch, and the state of the hook switch and the presence / absence of a busy tone in the telephone line are separately determined. Detect and
By disconnecting the telephone line from the hook switch and connecting it to the tone ringer when both the off-hook condition and the busy tone are detected and connecting the telephone line to the hook switch when the on-hook condition is detected, the handset may be disconnected. If the telephone device is left in the off-hook state, disconnection processing is performed to open the telephone line in a direct current condition, and a tone ringer is connected to the disconnected telephone line, as if it were in the normal on-hook state. Since a waiting state for incoming calls is formed, even if the handset of the telephone device is removed from the main unit and left in the off-hook state, it is possible to avoid a situation in which it cannot be called from other terminals and is in an unusable state. It has the effect of being able to.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a telephone device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a schematic operation of a main part of the apparatus shown in FIG.

FIG. 3 is a schematic configuration diagram of a conventional telephone device.

[Explanation of symbols]

 L Telephone line 1 Hook switch 2 Tone ringer 3 Call circuit 4 Handset 5 Dial transmission circuit 6 Numeric keypad 71 Hookoff detection circuit 72 Hookoff detection circuit 8 Line switching unit 9 Control circuit

Claims (1)

Claim: What is claimed is: 1. A hook switch for connecting / disconnecting a telephone line in a direct current manner in conjunction with picking up of a handset, and a first detection circuit for detecting the state of the hook switch. A second detection circuit for detecting a busy tone from the telephone line, a line switching unit interposed between the telephone line and the hook switch, and the detection state of the first and second detection circuits. By controlling the line switching unit, the telephone line is disconnected from the hook switch and connected to the tone ringer when both off-hook and busy tone are detected, and the telephone line is switched to the hook switch when on-hook is detected. A telephone device having a control circuit.