JP2895957B2 - Telephone with redial function - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a telephone provided with a redial function capable of automatically transmitting a dial signal repeatedly at predetermined time intervals until a destination answers.

(Prior Art) In a conventional telephone having an automatic redial function, when a called party is busy, a dial signal is input at a preset time interval by operating a redial key. The call is repeatedly transmitted, and the call to the other party can be continued until the other party answers or the caller cancels the redial mode.

(Problems to be solved by the invention) By the way, the telephone line to which this kind of telephone is connected,
In a case where another telephone (combined telephone) is connected in parallel and used, when a redial key is operated to repeat dialing at a predetermined time interval, another telephone may go off-hook. At this time, even if another telephone goes off-hook and is in a call state with another party, dialing is performed again after a predetermined time has elapsed, so that
There was a problem that the call was interrupted on another telephone.

The present invention has been made in view of the above problems, and an object of the present invention is to temporarily suspend redialing when one of two telephones connected to a telephone line is off-hook. It is an object of the present invention to provide a telephone with a redial function capable of preventing a call failure or the like.

(Means for Solving the Problems) In order to solve the above problems, the present invention relates to a telephone having a redial function of repeatedly dialing at a predetermined time interval until the other party answers, and a telephone connected to the device body. A determination means for detecting the voltage of the telephone line and determining the use state of the attached telephone connected in parallel to the telephone line; and determining that the attached telephone is being used by the determination means during the entire operation of the redial function. When it is determined, the operation of the redialing function is temporarily stopped, and when the redialing function is temporarily stopped by the determination means, the redialing function is temporarily stopped. And control means for resuming the above operation.

(Operation) Therefore, according to the present invention, during the operation of the redial function, when the judging means judges that the attached telephone is in use, the control means temporarily stops the operating redial function. Thus, it is possible to prevent the call from being attached to the attached telephone from being disturbed by dialing, and in the temporary stop state, when the determining means determines that the attached telephone is unused, the control means temporarily stops the operation. By restarting the stopped redialing function, it is possible to prevent the redialing from being terminated by the telephone call of the attached telephone.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an electrical configuration of a telephone A with a redial function according to the present invention.

In the figure, a telephone line 1 connected to a telephone exchange (not shown) includes a hook switch 2 and a line voltage detection circuit 5.
And are connected. Although not shown, another common telephone (combined telephone) B is connected to the telephone line 1 in parallel.

The hook switch 2 is connected to a speech network 3 for performing 2-wire to 4-wire conversion. The speech network 3 includes a bidirectional handset 4 having a microphone for transmitting and a receiver for receiving. , And an output of a tone transmitter 6 which is a dial transmitter for transmitting a dial signal is guided. The output of the key operation unit 7 is connected to the tone transmitter 6, and a dial signal is transmitted in response to a command signal from the key operation unit 7.

The output of the key operation unit 7 is controlled by the control circuit 8, and is set to the manual key for inputting the telephone number of the other party, the redial mode, and the latest telephone number is transmitted at predetermined time intervals. Key and a key for setting various other modes. The dial number data of the other party is sent to the tone transmitter 6 by a dial number input operation using a manual key of the key operation unit 7, and an automatic redial command signal is sent to the control circuit by a redial key input operation. 8 is given.

The control circuit 8 includes a microcomputer, and includes a timer unit 8a, a memory unit 8b, and an automatic redial control unit 8c. In addition to the command signal from the key operation unit 7, a detection signal from the line voltage detection circuit 5 is guided to the automatic redial control unit 8c. And a control signal is transmitted to the tone transmitter 6. Also,
Automatic redial control unit 8c, timer unit 8a, and memory unit 8b
Is a bidirectional connection.

The timer section 8a is for setting a time interval for automatic redial transmission, and is configured to provide time data to the automatic redial control section 8c. Also, the memory unit 8b
It stores the telephone number of the other party dialed most recently.

The automatic redial control unit 8c tone-tones the latest telephone number of the other party stored in the memory unit 8b at a time interval set in the timer unit 8a based on a command signal from the redial key of the key operation unit 7. Control for sending to the transmitter 6 is performed. In the redial mode, the automatic redial control unit 8c outputs a detection signal from the line voltage detection circuit 5 (a detection signal at this time is a signal that detects a voltage drop due to another telephone B being off-hook). ), The redial transmission operation is temporarily stopped, and the detection signal from the line voltage detection circuit 5 (the detection signal at this time detects a voltage return due to another telephone B being on-hook). Control to restart the redial transmission operation on the basis of this signal.

Next, the operation of the telephone with a redial function having the above configuration will be described.

First, when the user of the telephone A picks up the handset 4 to make a call and goes off-hook, the hook switch 2 is closed and a DC loop is formed with the telephone line 1. Next, when the user operates the manual key of the key operation unit 7 and inputs the telephone number of the other party, the data of the dial number is stored in the memory unit 8b, and the dial signal is transmitted from the tone transmitter 6. Then, it is transmitted to the telephone line 1 via the speech network 3 and the hook switch 2. At this time, if the other party is busy, the user temporarily goes off-hook and releases the hook switch 2.

Thereafter, when the user performs an input operation on the redial key of the key operation unit 7, a redial command signal is given to the automatic redial control unit 8c. Based on this command signal, the automatic redial control unit 8c sends out the latest destination telephone number stored in the memory unit 8b to the tone transmitter 6 at the time interval set in the timer unit 8a. At this time, the automatic redial control unit 8c outputs a control signal to the hook switch 2 to keep the hook switch 2 closed. As a result, a dial signal corresponding to the dial number of the other party is transmitted from the tone transmitter 6 and transmitted to the telephone line 1 via the speech network 3 and the hook switch 2. This dial signal is repeatedly transmitted at the time interval set by the timer section 8a until the other party answers.

In such a redial mode, if another telephone B goes off-hook, a DC loop is formed between the telephone and the internal circuit, and the voltage of the telephone line 1 drops. This voltage change is detected by the line voltage detection circuit 5,
The detection signal is sent to automatic redial control unit 8c.
The detection signal at this time is a signal indicating off-hook of another telephone B. The automatic redial control unit 8c releases the hook switch 2 based on the detection signal, and temporarily stops the redial operation, that is, the automatic transmission of the dial signal. As a result, the dial signal is not transmitted from the telephone A to the telephone line 1, so that the telephone signal B does not cause a call interruption while the other telephone B is talking.

Thereafter, when the telephone call ends and another telephone B is hooked on, the voltage of the telephone line 1 rises to a normal level. The voltage change at this time is detected by the line voltage detection circuit 5, and the detection signal is sent to the automatic redial control unit 8c. The detection signal at this time is a signal indicating on-hook of another telephone. The automatic redial control unit 8c
Based on this detection signal, the temporarily stopped redialing operation is started again. That is, the telephone number data of the other party stored in the memory unit 8b is read out at the time interval set by the timer unit 8a, and transmitted to the tone transmitter 6.
At the same time, the hook switch 2 is turned off-hook to form a DC loop with the telephone line 1. As a result, the dial signal of the other party is transmitted again from the tone transmitter 6 and transmitted to the telephone line 1 via the speech network 3 and the hook switch 2.

(Effects of the Invention) As described above, according to the present invention, dial transmission by the redial function is not performed when the attached telephone is in use, and dial transmission by the redial function when the use of the attached telephone is terminated. Resumes,
Even if the telephone with the redial function and the attached telephone are connected in parallel to one telephone line, the call on the attached telephone will not be disturbed by the redial transmission, and the call with the redial function will not be interrupted. This has the effect that the operation is not disturbed by the attached telephone.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an electrical configuration of a telephone with a redial function according to one embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Telephone line 3 ... Speech network 5 ... Line voltage detection circuit 6 ... Dial transmission part (tone transmitter) 7 ... Key operation part 8 ... Control circuit 8a ... Timer part 8b ... Memory part 8c ... Automatic redial control part

Claims (1)

(57) [Claims] 1. A telephone equipped with a redial function for repeatedly dialing at a predetermined time interval until a destination responds, detects a voltage of a telephone line connected to the device main body, and connects the telephone line in parallel to the telephone line. Determining means for determining the use state of the attached telephone; and, during the entire operation of the redial function, temporarily stopping the operation of the redial function when the determination means determines that the attached telephone is in use. On the other hand, control means for resuming the operation of the redial function when the judging means determines that the attached telephone is not in use while the redial function is temporarily stopped is provided. Phone to do.