JPH0236652A - Automatic direct inward/outward dialling system - Google Patents

Abstract

PURPOSE:To surely bring sound sensitivity into the sound sensitivity permissible range depending on the standards and to facilitate the reception of a telephone call by correcting a sound pressure level of a dial tone to a prescribed sound pressure and giving and output based on a sound pressure level correction data of a sounding body in response to the input/output characteristic. CONSTITUTION:The title system is provided with a memory 2 storing a sound pressure level correction data in response to a prescribed sound pressure level at every frequency used for a tone dial signal in response to the frequency characteristic of a sounding body 1 and conversion sections 9, 10 converting the signal level based on the sound pressure level correction data from the memory 2 so as to correct and output the sound pressure level of a dial tone. Thus, the frequency data signal of each number is corrected based on the data for correction and the result is outputted as the nearly constant sound pressure level. Thus, dial signal is surely received by an exchange in the range of the transmission frequency characteristic of the handset specified by the standards.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an auto-dial device that automatically dials a telephone number of a pre-registered destination.

More specifically, the present invention provides an acoustic link to a telephone line.

(Prior art) The acoustic coupling type auto-dial mW selects a pre-registered telephone number to call and outputs a sound corresponding to that telephone number, thereby dialing the telephone number on the butshuhon line'a (tone line). When making a call using this automatic dialing device (Japanese Patent Application Laid-Open No. 62-71359), it is possible to dial automatically.
One of the conditions for a to reliably receive a dialing signal is that the sound pressure level of the tone/dial sound output from the auto-dial device is the same as that specified in the standard standards of the S Machinery Manufacturers Association. It is necessary that the frequency characteristics fall within a predetermined permissible sensitivity range (shaded area) in the corresponding frequency band [see Figure 3 1°] Therefore, in conventional auto dial devices that are generally commercially available, the sound pressure To adjust the volume, either a volume adjustment mechanism is installed to increase or decrease the output volume of the tone/dial sound overall, or the sound pressure is fixed and adjusted by the distance between the auto-dial device and the telephone mouthpiece. Either one is adopted.

Also, when the sound from the telephone earpiece is input into the microphone after transmitting the first sound of the dialed number, and it is not determined that the signal is not received, that is, when the sound of two is still being emitted. An auto-dial device has been proposed in which the output state of the dial signal, for example, the sound pressure, is changed and the dial signal is output again (Japanese Patent Laid-Open No. 61-276457).

(Problem to be Solved by the Invention) However, there is a difference between whether the user adjusts it himself according to the situation or whether it is adjusted automatically, but in either case, the transmission of the entire tone/dial signal is They are similar in that they try to increase the reception probability by increasing or decreasing the sound pressure level with respect to the exchange, but there is still a problem that the probability that the exchange will receive a dial signal is as low as about 80%.

As a result of research into the reason why it is difficult to make calls when using an auto-dial device, the inventors of the present invention found that it is caused by the characteristics of the sounding body used in the auto-dial device. That is, from the low group frequency (697 to 941 Hz) used for the tone dial signal to the high group frequency (1209 Hz).
~1633Hz), there is no problem as long as the frequency characteristics of the sounding body fully satisfy the transmitting loudness standard and are flat, but the actual sensitivity of the sounding body depends on the type and configuration of the sounding body. For example,
Figure 4 shows the frequency characteristics of a piezoelectric buzzer, which is a common sounding device for auto-dial devices.As is clear from this graph, the sensitivity changes in the frequency range (697 to 1633 Hz) that makes up the tone dial signal. It is understandable that variations occur. Therefore, even if the transmission frequency characteristics of the telephone transmitter satisfy the standards, a situation may arise in which the dial tone output from the sounding body does not meet the standards. Even if you try to adjust the sound pressure by adjusting the volume or adjusting the distance M, it will only change the back pressure level overall as shown by the imaginary line in Figure 3, so if a specific frequency exceeds the upper limit of the allowable range or the lower limit. ■It was impossible to avoid the situation where the number of dials was less than 1, and the exchange was unable to reliably receive the dial signal.

The present invention provides an auto-dial device that can output a dial tone at a sound pressure level within the permissible sensitivity range of a transmitter defined by standards, regardless of the frequency characteristics of the sounding body used.
The purpose is to ensure that calls can be made.

(Means for Solving the Problems) In order to achieve the above object, the present invention stores a specific telephone number and uses a sounding body to emit a dial tone consisting of a predetermined frequency data signal corresponding to this telephone number by a dialing operation. The auto-dial device outputs data via a memory including a memory storing sound pressure level correction data for a predetermined sound pressure level for each frequency used for the tone dial signal according to the frequency characteristics of the sounding body; and a conversion section that converts the signal level of the frequency data signal based on the sound pressure level correction data, so that the sound pressure level of the dial sound is corrected and output.

(Function) Therefore, the frequency data signal of each number is corrected based on the data of the sound pressure level correction amount for the predetermined sound pressure level for each frequency used for the tone dial signal according to the characteristics of the sounding body. It is output as a nearly constant sound pressure level. Therefore, by setting the above-mentioned predetermined sound pressure level within the permissible sensitivity range in the range of low group frequency to high group frequency of the transmission frequency characteristic of the transmitter specified in the standard, the dial signal can be reliably received by the exchange. let

(Example) Hereinafter, the configuration of the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 shows a block diagram of an embodiment of an auto-dial device according to the present invention. , a memory 2 that stores various data and control programs, a switch unit 12 that sends a start signal to the CPU 3 at the time of dialing operation, and programmable frequency dividers 5 and 6 that form the frequency of the tone dial signal. , sine wave converters 7 and 8 that form a sine wave based on input signals, converters 9 and 10 that convert signal levels based on back pressure level correction data read from memory 2, and converter 9. , 10, and a sounding element 1 that outputs a dial tone.

Memory 2 is usually PROM, mask ROM, EPROM
, E2 PROM, RAM, etc., and stores attenuation or amplification correction data determined in advance for each frequency used according to the frequency characteristics of the sounding body 4, that is, the amount of sound pressure level correction for a predetermined sound pressure level. Also stored are a control program and data corresponding to frequencies used in tone dial signals, such as frequency division ratios, and dial data corresponding to one specific telephone number.

The frequency used for the tone dial signal is 69
Low group frequencies consisting of 4, 7Hz, 770Hz, 852Hz, 941Hz, and 1209Hz.

It consists of a total of eight frequencies including four high group frequencies of 1336 Hz, 1477 Hz, and 1633 Hz.

The CPU 3 to which clock pulses from the oscillator 4 are input has a function of controlling each part according to a program stored in the memory 2. This CPU 3 sends the frequency data corresponding to the telephone number stored in the memory 2 to the programmable frequency dividing sections 5 and 6, and controls the programmable frequency dividing sections 5 and 6, and also controls the sound pressure level of the sounding body 1. The modified data is sent to the converters 9 and 10 to control the converter 9.10.However, data sent to the programmable frequency divider 5.6 and the converter 9.10 is controlled by the CP.
In this embodiment, the programmable frequency dividing section 5.6, the sine wave converting sections 7, 8, and the converting sections 9, 10 are performed only when U3 receives one start signal from the switch section 12.
is made up of two systems, and is configured to process the low group frequency and the high group frequency separately. This is a tone dial signal (DTMF signal) of 697 to 941Hz.
This is because the signal is a combination and superposition of a low group frequency in the range of 1209 to 1633 Hz and a high group frequency in the range of 1209 to 1633 Hz, and it is necessary to process two different frequencies.

The programmable frequency dividers 5 and 6 receive the tally clock from the oscillation section 4, and divide the tally clock based on frequency division data from the CPU 3 to form a square wave of a predetermined frequency. For example, in a tone dial signal, the telephone number 1 (
1) on the keyboard can be displayed as a superimposed signal of a low group frequency of 697 Hz and a high group frequency of 1209 Hz. Therefore, if there is data 1 in the telephone number stored in the memory, the programmable frequency divider 5
The frequency division data corresponding to the low group frequency 697Hz is input to the programmable frequency divider 6, and the high group frequency 1209Hz is input to the programmable frequency divider 6.
Frequency division data corresponding to Hz is input, and square waves of 697 Hz and 1209 Hz are generated in each of the programmable frequency dividers 5 and 6.

The sine wave converter 7.8 is connected to the programmable frequency divider 5, 6.
It has the II function of converting a square wave inputted from a sine wave into a sine wave and generating a frequency signal. Further, this sine wave converter 7.8 is capable of generating a sine wave with a distortion rate below a specified value.

In this embodiment, the conversion units 9 and 10 are configured by programmable subtractors, and convert the frequency based on the sound pressure level correction data at the corresponding frequency of the sounding body 1 read out from the memory 2 together with the frequency division ratio, etc. attenuates the signal,
It has a function of correcting the output of the sounding body to a predetermined sound pressure level that falls within an allowable range in a predetermined frequency range of the transmission frequency characteristic. In other words, by inputting the sound pressure level correction data of the sounding body 1 stored in the memory 2 to the conversion section 9 and 10, the sound pressure level correction data of the sounding body 1 acts as an attenuation gain. , which attenuates the frequency signal. Here, the sound pressure level correction data of the sounding body 1 is obtained in advance for each of the eight frequencies used for the dial signal, and is expressed as a correction value for adjusting the sound pressure of the dial sound to a predetermined sound pressure level. be done. At this time, it is most preferable to find correction values for each sounding body, but this is disadvantageous in terms of productivity and cost, and if the sounding bodies have the same structure and composition and are manufactured on the same manufacturing rod,
Even if there is some variation, they have almost the same frequency characteristics, so there is no practical problem even if correction values are not determined for each sounding element.In this embodiment, the converters 9 and 10 are configured with programmable attenuators. However, it may be constructed using a programmable amplifier.

The MIX/AMP 11 mixes and amplifies the signals from the converter 9 and the converter 10. A function exists in which a high group frequency is superimposed on a low group frequency and amplified to a level that can drive the sounding body 1. Then, the signal from this MI
Although a piezoelectric buzzer is used in this example,
A small speaker or the like may be used, but one having flat sensitivity in the frequency range used for the tone dial signal is optimal.

Next, correction of the sound pressure level of the sounding body will be explained based on FIG. 2. In Figure 2 (a), ■ is the signal level (electrical signal) output from the handset according to the average characteristics of the four standard models of Nippon Telegraph and Telephone Corporation (NTT), and ■ is the signal level (electrical signal) output by From this figure, the sound pressure (predetermined sound pressure) of the dial sound input from the dial device to the transmitter is shown, and in Fig. 2 (b), ■ shows the frequency characteristics of the piezoelectric buzzer that is sounding #1. As is clear, the level difference between the dial sound pressure set to the appropriate fi pressure and the sound pressure level at each frequency of the sounding body varies depending on the frequency characteristics of the sounding body, so the overall sound pressure must be adjusted. However, it is not possible to shift the sound pressure level above the predetermined sound pressure level (2) at all frequencies.Therefore, as shown in FIG. 10, it is possible to obtain a predetermined sound pressure level, that is, a constant sound pressure level.In this embodiment, the predetermined sound pressure level is approximately a constant sound pressure (indicated by ■1).
Alternatively, the sound pressure level may be changed stepwise, and it is preferable to set a sound pressure level that adapts to as many NM telephones as possible.

Next, the operation of this embodiment will be explained. First, maneuver (start)
When a signal is input to the CPU 3 from the switch section 12, the C
PU3 reads out dial data (for example, frequency division ratio) corresponding to a specific telephone number stored in memory 2,
Programmable frequency divider 5 uses this data as frequency division data.
, 6. The CPU 3 also controls the tone length, signal generation,
a programmable frequency dividing section 5, which sequentially reads each data of the pause time and the sound pressure level correction amount from the memory 2 for each frequency corresponding to each number, and controls the programmable frequency dividing section 5.6 based on this data; 6 divides the clock pulse of the oscillator to generate a square wave with a low group frequency and a high group frequency corresponding to the tone dial, and the sine wave converter 7 in the next stage
, 8. The sine wave converters 7 and 8 convert the square waves from the programmable frequency dividers 5 and 6 into sine waves having a prescribed distortion rate or less, and generate frequency signals. The configuring programmable attenuator is the sine wave variable jp! Frequency signals from #7 and #8 are inputted, and sound pressure level correction data of the sounding body 1 stored in the memory 2 is inputted via the CPU 3. Then, the converting units 9 and 10 sequentially attenuate the frequency signals by using the back pressure level correction data of sound generation #1 as an attenuation gain [FIG. 2(c)], and the frequency signals output from the converting units 9 and 10. is input to the next stage MIX/AMP 11, where the high group frequency is superimposed on the low group frequency and then amplified. Then, the series of operations ends when the number is 0 or more, which is input to the sounding body 1, converted into a dial tone by the sounding body 1, and outputted to the outside.

In this embodiment, only the case where the sound pressure level correction data of the sounding body 1 is stored in the memory 2 has been described, but it may also be configured to be stored in a Daijisui Guchi, PAL, etc.
Further, in this embodiment, only a configuration in which one specific telephone number is stored in advance has been described, but a writable RAM
, E2 PROM, etc. as the memory 2, and a numeric keypad and function keys installed, it can be applied to cases where multiple dial data are written in advance, or to an auto dial device that allows the written contents to be corrected as necessary. is also possible.

Further, in this embodiment, the CPU 3 and the memory 2 are configured separately, but if a 1-chip CPU is used, the memory 2 is not separately required.Furthermore, it goes without saying that the present invention can have a discrete configuration without using the CPLI. stomach.

(Effects of the Invention) As is clear from the above explanation, the present invention is capable of adjusting the sound pressure level of a dial sound based on the sound pressure level correction data for each frequency of use of the sounding body, which is determined according to the input/output characteristics of the receiver 4 side. The system converts the sound pressure and corrects it to the specified sound pressure before outputting it, so the range of frequencies used for the tone dial signal with the transmission frequency characteristics specified in the standard for the exchange to reliably receive the dial signal. can be reliably kept within the permissible pitch range, making it easier to make calls.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of an automatic dialing device of the present invention. Figure 2 is a graph explaining the sound pressure level 8M of the sounding body, and (a) shows the relationship between the sound pressure of the auto dial device and the level of the signal output from the transmitter.
(b) shows the frequency characteristics of the piezoelectric buzzer, and (c) shows the relationship between the frequency characteristics of the piezoelectric buzzer and the predetermined sound pressure set for the auto dial device, as well as the sound pressure level correction method. Figure 3 is based on the standard. FIG. 4 is a graph showing the frequency characteristics of the transmitter, and FIG. 4 is a graph showing the frequency characteristics of the sounding body. 1...Sounding body, 2...Memory, 9.10...Conversion section. Figure 2 factor (a) Figure 2 (b) Figure 4/4th Figure 2 (C) Frequency (Hzl -1111 frequency fi (Hz +

Claims (1)

[Claims] In an auto-dial device that stores a specific telephone number and outputs a dial tone consisting of a predetermined frequency data signal corresponding to the telephone number by a dialing operation via a sounding body, a tone/tone is output according to the frequency characteristics of the sounding body. A memory storing sound pressure level correction data for a predetermined sound pressure level for each frequency used in the dial signal, and a conversion for converting the signal level of the frequency data signal based on the sound pressure level correction data from the memory. What is claimed is: 1. An auto-dial device comprising: a dial tone;