JPS61230452A - Telephone set circuit - Google Patents

Abstract

PURPOSE:To eliminate a power supply backing up a storage circuit for a long time by providing a redialing block means blocking the redialing after a prescribed elapses after non-hook of the telephone set when dialing and talking and finished. CONSTITUTION:A dial number comprising a series of numeral information is sent to a telephone station line 7 and stored in a storage circuit 4. In case of the end of talking or in busy state, a telephone set hooks on and the information in the storage circuit 4 is held. In this case, a timer 8 starts operation as soon as the telephone set hooks on to block the execution of redialing after a prescribed time elapses. When the telephone set is in use during the operation of the timer 8, the timer 8 starts its operation after the telephone set hooks on again. Thus, the redialing function is set to the most effective time width, the frequency of occurrence of unexpected mistake due to confusion as a conventional circuit is decreased an the backup of the required power supply is eliminated or minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electronic telephone circuit, and particularly to a telephone circuit having a redial function. Here, the "re-dial function" refers to a function that stores the most recently dialed number and sends a dial signal for this number to the line by pressing a button.

(Summary) The present invention prevents redialing from occurring after a certain period of time has elapsed after the dialing and conversation operations are completed and the telephone goes on hook in a telephone circuit having a redialing function. This eliminates the need to keep power supplied for a long time, and also prevents the user from misrecognizing a memorized redial number due to mistake or the like.

[Conventional technology]

There are two types of dial signal generation methods for telephones: a tone method that generates a two-frequency part signal that corresponds to the dialed digits, and a pulse method that generates a pulse train that corresponds to the dialed digits. Conventionally, the tone system consisted of an electronic circuit such as an LC oscillation circuit or an RC oscillation circuit and a push-button keyboard, while the pulse system consisted of a low redial system that had a mechanism for disconnecting the telephone office line.

In recent years, as all kinds of electronic equipment have become integrated circuits, both of these systems have been realized in integrated circuits in telephone circuits. In particular, in the case of the pulse type, conventional mechanical parts were replaced with equivalent electronic circuits, and the shape of the keyboard changed from a low redial to a push button type keyboard.

Since the tone system is originally an electronic circuit system, it can be implemented relatively easily by changing the LC oscillation circuit or CR oscillation circuit section to a digital synthesis system that is easier to integrate.

On the other hand, in integrating the pulse method into an integrated circuit, it is necessary to replace the pulse generation mechanism with an electronic circuit, and when keyboard input is adopted, the time required for key input is reduced.
Since the time required to send out a pulse train corresponding to each number is generally not equal, a storage circuit is required to temporarily store key manual information. Separately from the key capotain for dialing, a button is provided to recall the memory contents, and by providing a function to send out a pulse train according to the recalled memory contents, simply by pressing this button, the same button can be used again. You can call your opponent. This function is called a so-called redial function.

In addition, due to the simplicity of this re-dial function, integrated circuits that employ this re-dial function have appeared even in tone systems that do not originally require a memory circuit.

The present invention relates to a telephone circuit having this memory circuit.

FIG. 3 is a block diagram showing an example of such a conventional telephone circuit. In the figure, 1 is a dial keyboard, 3 is a key input circuit that converts key input input into the dial keyboard I into a predetermined pulse train and outputted, and 4 is a memory that temporarily stores the output of this key input circuit 3. The circuit 2 is a re-dial button for recalling the contents stored in the memory circuit 4, and the output thereof is converted into a predetermined pulse signal by the key input circuit 3 and input to the memory circuit 4. 5
6 is a waveform shaping circuit that generates a predetermined dial signal according to the contents stored in the memory circuit 4; 6 is an output circuit that sends the output signal of the waveform shaping circuit 6 to the telephone office line 7;

The memory circuit 4 for redialing needs to retain its contents in preparation for the next redialing operation even when the telephone is not used for a long time, and a so-called bank-up power supply is required.

There are ways to achieve this, such as by using the voltage of the telephone office line, by using batteries, and by using large capacity capacitors, but in any case, the contents of the memory circuit can be stored for as long as possible. Efforts have been made to ensure that it can be maintained over a long period of time.

[Problem that the invention seeks to solve]

However, telephone circuits using the conventional storage circuit holding method as described above have the following drawbacks.

First, when using the re-dial function, it is almost always the case that the caller cannot call the other party due to a busy situation, and the call is made again several minutes to several tens of minutes later, and it is rare that the caller waits for several hours. Conversely, if you have to wait several hours, you will not be able to dial anyone else during that time. Additionally, if multiple people are using the same phone, the contents of the memory circuit may
There is no guarantee that it is what you just dialed. In such a case, redialing may result in calling an unexpected party, which may cause trouble.

On the other hand, there is a method of adding a function to arbitrarily erase the contents of the memory circuit, but this is cumbersome to execute, and the advantage of re-dialing is also lost.

In this way, it is preferable that the time required for the redialing function be relatively short, and if it exceeds this time, it is preferable to disable redialing.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks, eliminate the need for a power supply bank-up required for redialing, or minimize the size of the power bank, thereby preventing connection to an unexpected party due to mistake or the like. The objective is to provide a telephone circuit that reduces accidents.

[Means for solving problems]

The telephone circuit of the present invention includes a memory circuit for storing a dial signal sent to a line, and circuit means for sending the dial signal stored in the memory circuit to the line again as a dial signal by operation. The present invention is characterized by comprising a timer means for counting a certain period of time from the end of use of the telephone and sending out an output, and means for blocking the operation of the circuit means by the output of the timer means.

[For production]

In the telephone circuit of the present invention, the redial function can be set to the most effective time width by means of a blocking means including, for example, a timer, which prevents redialing after a predetermined period of time has elapsed from the on-footer of the telephone after the end of the dialing and conversation operations. The frequency with which unexpected mistakes occur due to mistakes as in the past can be greatly reduced, and the required power backup can be made unnecessary or minimized in size.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. 1 is a dial keyboard, 2 is a redial button, 3 is a key input circuit, 4 is a key input information storage circuit, 5
is an output waveform shaping circuit, 6 is an output circuit, 7 is a telephone office line,
8 is a timer for backing up the memory circuit.

Here, the feature of the present invention is that a time limit timer 8 is provided to measure a certain period of time after the telephone is no longer in use, and when this certain period of time has elapsed, redialing based on the information in the memory circuit 4 is prevented. It's there.

Now, for dial operation, dial keyboard 1
When one of the numeric buttons is pressed, the information passes through the key input circuit 3 and is temporarily stored in the memory circuit 4. The output waveform shaping circuit 5 shapes the output waveform in order from the oldest information while the information is stored in the storage circuit 4, and sends the shaped output waveform to the output circuit 6. A dial signal is then sent to the telephone office line 7 through the output circuit 6.

In this way, the dial number consisting of a series of numerical information is sent to the telephone office line 7 and simultaneously stored in the memory circuit 4. After the call is over or during a call, the telephone is placed on-hook and the information in the memory circuit 4 is retained by the method described above. At this time, the timer 8 starts operating as soon as the telephone is on-hook, and prevents the execution of a redial operation after a predetermined period of time has elapsed. If the telephone is used while the timer 8 is operating, the timer 8 starts operating from the time the telephone is hooked up again.

FIG. 2 is a block diagram showing another embodiment of the present invention. This embodiment is different from the embodiment shown in FIG. 1 in that a display device 9 is provided. This display device 9 is added to clarify the redial prevention means, and can display, for example, a liquid crystal display to indicate whether or not the redial function is working.

In the above-mentioned embodiment, the blocking method as the redial blocking means is to blank out the contents of the memory circuit, to prevent the contents of the memory circuit from coming out, or to prevent the output pulse train from being sent out. The present invention can be implemented in the same manner as long as the output of the storage circuit is substantially prevented from being output to the telephone office line.

〔Effect of the invention〕

As explained above, the telephone circuit of the present invention, in addition to the conventional memory circuit for a redial function, also provides a redial function that prevents a redial operation after a certain period of time has elapsed after dialing and call operations are completed and the telephone is turned off. Since there is a blocking means, there is no need for a power supply to back up the memory circuit for a long time, or a power supply of minimal size is required, making it more economical and preventing connection to an unexpected party when re-dialing. This has the effect of reducing accidents such as accidents. Furthermore, there is an added effect of reducing the complexity of rewriting the contents of the memory circuit to maintain confidentiality immediately after a call.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 2 is a block diagram showing another embodiment of the present invention. FIG. 3 is a block diagram showing a conventional example. DESCRIPTION OF SYMBOLS 1... Keyboard for dialing, 2... Button for redialing, 3... Key input circuit, 4... Memory circuit, 5
... Output waveform shaping circuit, 6... Output circuit, 8...
Timed timer, 9...Display device.

Claims (2)

[Claims] (1) A telephone circuit equipped with a memory circuit for storing a dial signal sent to a line, and circuit means for sending the dial signal stored in this memory circuit to the line again as a dial signal by operation, 1. A telephone circuit comprising: timer means for counting a predetermined period of time from the time of termination and transmitting an output; and means for blocking the operation of the circuit means by the output of the timer means. (2) The timer means includes a display circuit that displays to the operator that a certain period of time has been counted.
Telephone circuits as described in Section.