JP4778454B2 - Connection line type setting method and telephone circuit - Google Patents

Description

  The present invention is an analog telephone connected to a switching device such as a central office switching device, a private branch exchange, a button telephone device, etc., and prevents side-side sound control in accordance with the type of connection line of external line / internal line, thereby improving the quality of the call. The present invention relates to an improved telephone circuit.

  Normally, the telephone connected to the telephone line in a private branch exchange such as a private branch exchange or a button telephone apparatus is not only for the telephone line serving as the extension of the private branch exchange but for the telephone station serving as the external line of the private branch exchange. It may be used directly connected to the subscriber line of the exchange. On the other hand, in order to prevent a side sound that goes from the telephone handset to the handset, it is necessary to obtain an impedance balance with the connected telephone line. For this reason, the communication circuit connecting the transmitter and the receiver is provided with a side-tone balance network. However, the length of the telephone line connecting the switching device and the telephone is not only long for the internal line but long for the external line, and the distance varies. Adjustment is required. Hereinafter, the outside line is referred to as the outside line corresponding to the extension line, but it is the same as the subscriber line of the telephone station exchange called the office line.

  As a conventional telephone circuit, for example, Japanese Patent Laid-Open No. 63-94752 (Patent Document 1) is disclosed. This telephone circuit is equipped with a balanced network for internal and external lines, to prevent side noise by switching connection for the internal line when the telephone is connected to the internal line and for the external line when the telephone is connected to the external line. The equilibrium is maintained.

  This will be explained with reference to FIG. 3. In the telephone 110, when the telephone line is connected by the hook switch, the side tone balance switching holding circuit 111 checks the state of the external line switch 112, and when it is "ON" The external line side sound balance circuit 111 -A is connected to the call circuit 14. When the state of the outside line switch 112 is “off”, the extension side sound balance circuit 111 -B is connected to the call circuit 14.

  However, in the telephone circuit of Patent Document 1, the person in charge of telephone installation work needs to set the external line switch to “ON” when connecting the telephone to the external line. If this setting is forgotten, the side sound will be unbalanced and the side-side sound circuit will not function, and it will be unavoidable that this will interfere with the call.

  For example, JP-A-8-172475 (Patent Document 2) discloses an anti-side sound circuit system that automatically adjusts to solve such a problem. This telephone has a bridge-type telephone circuit as a side-to-side sound circuit, and a non-linear resistance element or variable capacitance element is used as one of the elements, and a side sound corresponding to the current or voltage at the connection end of the telephone line is used. The balance can be automatically adjusted continuously.

  This will be described with reference to FIG. 4. In the telephone 120, the call circuit 122 connects the receiver 15-A and the transmitter 15-B, and has a bridge circuit corresponding to current or voltage as a protection-side sound circuit. When a telephone line is connected to the call circuit 122 via a hook switch, side sound balance is maintained according to the magnitude of the current value or voltage value at the telephone line connection terminal. A diode, a varistor, or the like is applied to the non-linear resistance element.

  However, even with this method of automatically optimizing the side-tone balance circuit constant of the call circuit, it is necessary to automatically optimize the call level over a wide band due to problems such as the occurrence of changes in device characteristics over time and the size of the application range. The question remains.

  Also, in private branch exchanges, private branch exchanges, etc., taking into account the power consumption and the conditions of externally connected telephones, the impedance of the telephone line is artificially increased to suppress the dial tone level and line current. May have. In such a case, for example, in the state where the external line is connected to the internal line, the line current of the internal line connection is 20 mA or less, and therefore the conditions are the same as those when the external line of the long-distance station is connected. Under this condition, the audio level amplification is large. For example, if an external line is connected, the line current is 40 mA, and the audio level is “−20 dBm”, the audio level is “−26 dBm” when the line is connected to the extension as it is. Therefore, if the extension is connected to the handset with the outside line set, it will be heard at a very high voice level, so it is necessary to automatically detect the type of the connected telephone line and avoid such a situation. There is.

Japanese Unexamined Patent Publication No. 63-94752 JP-A-8-172475 JP-A-6-14357

  The problem to be solved is to automatically detect the outside line / internal line type of the connected telephone line in the telephone connected via the switching device, and to optimize the side tone balance circuit of the telephone circuit corresponding to the telephone line. This is not possible with simple control.

  Therefore, in the above-mentioned Patent Document 1, whether the internal line connection or the external line connection is manually detected by the telephone, this is automatically detected, and a side tone balance circuit suitable for each is selected and connected to the telephone line. It is possible.

  For example, in Japanese Patent Application Laid-Open No. 6-14357 (Patent Document 3), an external line connection code added to the head of a dial when making a call from a private branch exchange is used as a telephone number when a destination telephone number is connected to a telephone exchange. A technique for automatically adding the is disclosed. That is, in the communication terminal device of Patent Document 3, it is identified whether the connection is an outside line connection or an extension line connection based on the difference in the type of dial tone received from the exchange side off-hook. However, the technique according to Patent Document 3 is irrelevant to the optimization of the side tone balance circuit.

  On the other hand, since there are a wide variety of dial tones sent from telephone exchanges in each country, the frequency and intermittent pattern of dial tones sent from the switching equipment to the extension are sent from the telephone exchanges in that country. May be indistinguishable from the dial tone.

  Therefore, in order to realize further optimization automatically with a simple control circuit, it automatically detects whether the telephone line connected by the telephone is an internal line or an external line, and selects a side tone balance circuit suitable for each. Then, it is desired to connect to the telephone line and optimize the telephone conversation level in each connection state range. For this purpose, it is necessary to take into account not only the type of the dial tone but also other conditions to ensure the accuracy of selection.

  On the other hand, as described above, the external line, which is a subscriber line from a central office switch, and the extension of a private branch exchange, when the line is connected, depending on the type of the connection line, the dial tone level and the telephone line terminal The flowing line current value is different. These levels and current values are not a problem when there is a large difference between the external line and the internal line, but depending on the conditions of the connected telephone line, the identification range may overlap and the external line and the internal line may not be distinguished. .

  In order to solve the above problems, the connection line type setting method according to the present invention aims to automatically realize the optimization of the side tone balance circuit in the communication circuit corresponding to the telephone line connected to the telephone with a simple control circuit. The main feature is to determine whether the telephone line type is either an external line or an internal line by combining multiple conditions of the telephone line to which the telephone is connected, and further adjust the signal level based on that condition is doing.

  Therefore, in setting the connection line type, when an analog telephone connected to the switching device is connected to the telephone line, a plurality of conditions of the telephone line, such as the dial tone type, the dial tone level, and the telephone line terminal are set. The value of the flowing current is detected, and the connection line type of the switching device is determined to be an external line or an extension line from each detected condition, and the type of the external line / extension line is determined based on the majority or majority decision. As a result, a side-tone balance circuit suitable for it is connected to the call line, and the call current and the voice level on the transmission / reception path are adjusted to appropriate values. After the adjustment, the handset and handset accessed by the user are connected to the telephone line.

  Specifically, the side tone balance circuit is set and connected in advance for an external line or an internal line, and the conditions of the signal level and the current value when connected to a telephone line are set in advance for each of the external line and the internal line. Set and determine the type of external / internal line of the connected telephone line based on the majority decision from the above three conditions when making a call from the telephone, and process whether to switch the side tone balance circuit from the current state is doing.

  With such a configuration, it is determined whether the connection is an external connection or an internal connection by combining these, such as the type of dial tone, the dial tone level, and the current value flowing through the telephone line terminal. Can be switched automatically. Also, the voice level can be adjusted using the dial tone level and the current value flowing through the telephone line terminal. Furthermore, since the transmitter / receiver circuit is connected to the telephone line after the adjustment, the side tone balance circuit and the voice level adjustment do not mix the outside line / internal line. As well as the highest call quality. This setting is not necessary after the phone is set up for the first time it is connected to an external or internal line. Furthermore, the telephone circuit according to the present invention can automatically check whether the connection is an external line connection or an internal line connection every time a call is made, so that its function is stable. In the unlikely event that it is not possible to automatically confirm whether the connection is an external line or an internal line, consider the identification of the external line / extension line by the user, and at least the extension tone of the exchange device should be set so that it can be identified by the dial tone. By changing to an identifiable one, the extension detecting means on the telephone side can be changed accordingly.

  On the other hand, the telephone circuit of the analog telephone connected to the exchange apparatus according to the present invention realizes automatic optimization of the side tone balance circuit of the telephone circuit corresponding to the telephone line to be connected. An external line side sound balance circuit, an internal line side sound balance circuit, a side sound balance switching holding means, a detection measurement means, an external line / extension type determination means, and a control means are provided.

  The side sound balance switching holding means holds one of the external line side sound balance circuit and the extension side sound balance circuit connected to the other speech circuit. The side sound balance switching holding means, when receiving a balance circuit switching instruction from the control means, switches the connected external sound side balance circuit or extension side sound balance circuit to the other and connects it to the communication circuit and holds it. To do.

  The detection and measurement means detects or measures each of a plurality of line conditions including a dial tone and a line current input from the telephone line when connected to the telephone line and making a call from the telephone.

  The external line / internal line type determining means presets the external line / internal line conditions to be connected and held by the side tone balance switching holding means for each of the plurality of conditions of the telephone line, and when the call is transmitted from the telephone, A plurality of conditions are measured and compared with preset conditions, and the external / internal line type is determined under each condition.

  The control means receives a plurality of external / extension types determined by the external / extension type determination means when making a call from the telephone, determines the external / extension by the majority or majority, and sets the external line to the side tone balance circuit. The side sound balance switching holding means is instructed to set up a connection for use / extension.

  The external line / external line type determination means includes a plurality of line conditions that are received when a call is made from a telephone connected to the telephone line and received from the telephone connected to the telephone line. It is desirable to include the signal level of the dial tone and the current value of the telephone line that flows to the input terminal when a call is made from the telephone connected to the telephone line.

  Further, the type of the dial tone can be detected at least in Japan when the continuous tone is an external line and the intermittent tone is an internal line. Furthermore, the switching device can be set so that the type of the telephone exchange or switching device to be connected can be determined by detecting the frequency and the type of intermittent sound.

  The external line / extension type determination means can specifically determine an external line when the current value is 40 mA or more, or an extension line when the signal level is “−20 dBm” or more.

  The telephone circuit further includes voice level adjustment means for receiving a voice level adjustment instruction and transmitting the voice level adjustment instruction to the telephone circuit to adjust the voice level of each of transmission / reception of the telephone, and the control means includes a dial tone level determination means and a line. The voice level adjustment value is obtained from the measurement value obtained from the current determination means, and the adjustment instruction is output to the voice level adjustment means. After the voice level is automatically adjusted, the telephone line is connected via the call circuit. Connected to the transmitter / receiver circuit.

  The telephone circuit of the present invention has various conditions for the telephone line to which the telephone is connected, for example, the type and signal level of the dial tone received when making a call from the telephone, and the current value at the telephone line input terminal. The range for determining the connection line type is set in advance. Therefore, the telephone circuit determines the connection line type of the external line / internal line by combining the dial tone type, signal level, and current value detected when making a call from the telephone, and sets the side tone balance circuit suitable for the call line. Connected to. Thereby, the side sound is automatically suppressed accurately, and a comfortable call can be realized. Also, the audio level is automatically adjusted based on this condition. As a result, the call current and the voice level in the transmission / reception are automatically adjusted to appropriate values, and then the telephone line is connected to the transmission / reception circuit, so that not only the optimum sound quality can be obtained, Further improvement in call quality can be obtained.

  When the telephone circuit connects the telephone line, the external line / extension line type is comprehensively identified by the multiple conditions of the connected telephone line, and the external line / extension type is determined based on the determined connection line type. , And a side-tone balance circuit suitable for it is connected to the speech circuit. Therefore, the multiple conditions of the telephone line are the three of the type and signal level of the dial tone received when making a call from the telephone and the current value at the telephone line input terminal, and from each determination, the majority or majority of the determination, In other words, it is determined as a type that has obtained more than two-thirds or at least one determination.

  Embodiments will be described below with reference to the drawings. In the drawings, some components according to the present invention are included, but some components essential as an apparatus are omitted. The functional distribution of the blocks and the operation order of the flow can be freely changed as long as the gist of the present invention is not impaired, and the present invention is not limited to the following description.

  A first embodiment of the present invention will be described with reference to FIG.

  FIG. 1 is an explanatory diagram showing in block form one embodiment of a telephone according to the present invention.

  The illustrated telephone 10 is an analog telephone, and includes a hook switch circuit 11, a telephone line interface 12, a dial transmission circuit 13, a communication circuit 14, a receiver 15-A, a transmitter 15-B, a tone ringer circuit 16, and a side tone balance. Switching holding circuit 17, external side sound balance circuit 17-A, extension side sound balance circuit 17-B, voice level adjustment circuit 18, telephone control circuit 19, dial tone type detection circuit 21, dial tone level measurement circuit 22, And a line current measuring circuit 23. The telephone control circuit 19 includes an outside / internal line determination setting function 20. The dial tone type detection circuit 21, dial tone level measurement circuit 22, and line current measurement circuit 23 are obtained by dividing the above-described detection measurement means according to conditions, and the external line / extension line type determination means is an external line / extension determination setting function 20. include.

  One of the hook switch circuits 11 is connected to the telephone line, and the other is connected to the telephone line interface 12 and the tone ringer circuit 16. The telephone line to be connected is an extension line to the telephone exchange device or an external line to the telephone office exchange. The hook switch circuit 11 connects the telephone line to the telephone line interface 12 in the off-hook state, and connects the call signal received in the on-hook state to the tone ringer circuit 16.

  The telephone line interface 12 connects a telephone line to be connected via the hook switch circuit 11 to the dial transmission circuit 13, the communication circuit 14, the dial tone type detection circuit 21, the dial tone level measurement circuit 22, and the line current measurement determination circuit 23. To do. The telephone line interface 12 is not only connected to the telephone exchange device of the other party via the telephone line in the off-hook state of the hook switch circuit 11 but also exchanges signals with the telephone control circuit 19 to make a calling procedure or incoming call of the telephone 10. Perform the call procedure.

  The dial transmission circuit 13 has a dial pad provided with buttons operated by the user, receives the control of the telephone control circuit 19, and transmits the dial number designated by the user when the telephone 10 makes a call to the telephone line interface 12 and the hook. A call is sent to the telephone line via the switch circuit 11.

  The call circuit 14 connects a telephone line connected to the telephone line interface 12 to the handset 15-A and the handset 15-B via a protection-side sound circuit. Further, an external line side sound balance circuit 17-A or an internal line side sound balance circuit 17-B for the side-proof sound is connected to the side-side sound circuit via the side-tone balance switching holding circuit 17, and the receiver 15 An audio level adjustment circuit 18 for adjusting the audio level of -A and the transmitter 15-B is connected. The handset 15-A and the handset 15-B may be handset handsets. The receiver 15-A may be an earphone, a headphone, a speaker, or the like. The microphone 15-B may be a microphone.

  The tone ringer circuit 16 receives a call signal from the telephone line via the hook switch circuit 11 in the on-hook state, and broadcasts an audible sound due to ringing or the like. The side sound balance switching holding circuit 17 is controlled by the telephone control circuit 19, and connects the external line side sound balance circuit 17-A or the extension side sound balance circuit 17-B to the call circuit 14 according to the instruction. Hold. The external line side sound balance circuit 17-A or the internal line side sound balance circuit 17-B has an external line or internal line side sound balance circuit network. The voice level adjustment circuit 18 is controlled by the telephone control circuit 19 and is connected to the call circuit 14 to automatically and optimally adjust the voice levels of the receiver 15-A and transmitter 15-B. The level adjustment is switched by the external line connection setting or the internal line connection setting. In the case of the external line connection setting, the level adjustment is automatically adjusted based on the telephone line current. On the other hand, the audio level can usually be manually adjusted by the user.

  The telephone control circuit 19 is composed of, for example, a program-controlled processor and memory, and is connected to the components of the telephone 10 to control the function of the telephone 10. In particular, according to the present invention, the outside line / internal line determination setting function 20 receives the respective detection measurement information from the dial tone type detection circuit 21, the dial tone level measurement circuit 22, and the line current measurement circuit 23, and the external line / extension determination function 20 The extension is determined, and from the result, it is determined whether the connected telephone line is an external line or an extension line, and control instructions for setting each are given to the side tone balance switching holding circuit 17 and the voice level adjusting circuit 18. Details thereof will be described later with reference to a flowchart.

  The dial tone type detection circuit 21 receives dial tone from the telephone line via the hook switch circuit 11 in the off-hook state and the telephone line interface 12 when the telephone 10 performs a call operation. Whether the received dial tone is a continuous tone or an intermittent tone is detected, the continuous tone is notified to the external line / extension determination setting function 20 of the telephone control circuit 19 as an external line and the intermittent sound as an internal line. Depending on the connected telephone exchange device, the difference may be notified by detecting the type of at least one of frequency and intermittent sound.

  On the other hand, as for the type of dial tone, at least in Japan, continuous tone can be detected by an outside line and intermittent tone can be detected by an extension line, but globally, dial tone sent from a telephone exchange in each country is frequency and intermittent pattern. It is a wide variety. For this reason, the frequency of the dial tone transmitted from the switching device to the extension and the intermittent pattern may be indistinguishable from the dial tone transmitted from the telephone exchange in that country. Therefore, if necessary, it is possible to identify the extension dial tone of the switching apparatus to which the telephone is connected from the external dial tone so that the user can identify the external line / extension line, and at least the dial tone can be identified. It is preferable to change the extension detection means on the telephone side accordingly.

  The dial tone level measuring circuit 22 receives dial tone from the telephone line via the hook switch circuit 11 and the telephone line interface 12 in the off-hook state when the telephone 10 performs a call operation. The dial tone level measurement circuit 22 measures the level of dial tone received from the telephone line, and notifies the external line / extension determination setting function 20 of the telephone control circuit 19 of the level measurement value. Usually, the outside line is often low because the line length is long, but it is relatively high in the case of a short distance. On the other hand, the extension has a short line length, but can maintain an appropriate level by adjusting the level on the exchange side.

  For example, when the line level is set to 40 mA and the audio level is adjusted and “−20 dBm” is set for the external connection, “−26 dBm” is set for the extension connection, and the level increases by about 6 dB. Therefore, when an internal connection is made with such an external connection setting, sound summarization occurs as a side sound in both the sum and the received call. For this reason, in Japan, the dial tone level is set to “−15 dBm”. In this embodiment, when “−20 dBm” or more is detected as the dial tone level, it is determined as “extension”. However, if the dial tone level is less than “−20 dBm”, it is either an external line or an internal line and cannot be identified.

  A telephone line is directly connected to the line current measuring circuit 23 via the hook switch circuit 11 and the telephone line interface 12 in an off-hook state. The line current measuring circuit 23 measures the telephone line current, and notifies the outside line / extension determination setting function 20 of the telephone control circuit 19 of the measured current value. Normally, in the outside line, the current value changes according to the length of the telephone line. In the extension, although the line length is short, there is a relation of power consumption, and the current value is relatively small and is set to 20 mA or less.

  Therefore, in this embodiment, when the line current “40 mA” or more is detected, it is determined as “outside line”. However, if the line current is less than “40 mA”, it is either a long-distance outside line or an inside line and cannot be identified.

  The external line / internal line determination setting function 20 receives the measurement values from the dial tone level measurement circuit 22 and the line current measurement circuit 23, and determines the external line / internal line from the measurement values in each.

  According to the above-mentioned conditions, when connected to the extension telephone line, the dial tone type detection circuit 21 determines the extension from the intermittent tone, and the dial tone level measurement circuit 22 detects “−20 dBm” or more to detect the extension. judge. Accordingly, the outside line / internal line determination setting function 20 determines the extension setting by the majority or majority of “2/3”. When connected to an external line, the dial tone type detection circuit 21 determines the external line from the continuous sound, and the line current measurement circuit 23 detects the line current value of 40 mA or more to determine the external line. Accordingly, the outside line / internal line determination setting function 20 determines the outside line setting by a majority or majority of “2/3”.

  However, when the dial tone level measurement circuit 22 detects “−20 dBm” or more and determines that it is an extension, the line current measurement circuit 23 detects a line current value of 40 mA or more and determines that it is an external line, which is an abnormal state. A predetermined warning is generated and displayed to the user or the installer.

  Next, the main operation procedure in the telephone 10 will be described with reference to FIGS. 2A and 2B and FIG. Here, it is assumed that the dial tone received from the telephone line is a continuous tone when it is from the outside line and an intermittent tone when it is from the extension line. It is assumed that the dial tone level detects “−20 dBm” or more to determine an extension, and the telephone line current value detects 40 mA or more to determine an outside line.

  When the telephone switch 10 detects that the hook switch circuit 11 is off-hook by the user's call, the telephone line is changed from the telephone line interface 12 to the dial tone type detection determination circuit 21, dial tone level measurement circuit 22, and line current measurement circuit. 23 (step S1). At this time, since the telephone control circuit 19 has received off-hook information from the hook switch circuit 11, the telephone control circuit 19 recognizes the call and makes a call process (procedure S2) from the telephone line interface 12 to the connected switching apparatus via the telephone line. )I do.

  As a result of this processing, a dial tone is sent from the connected telephone exchange or exchange device. Therefore, the dial tone type detection circuit 21 detects whether the received dial tone is an intermittent tone, and sends it to the outside line / extension determination setting function 20. Notification is made (procedure S3). The dial tone level measurement circuit 22 measures the received dial tone level and notifies the measured value to the outside line / inline determination setting function 20 (step S4). Further, the line current measuring circuit 23 that has drawn in the telephone line in the procedure S1 measures the line current and notifies the outside line / extension setting function 20 of the measured value (procedure S5).

  The external line / extension determination setting function 20 that has received each of the above notifications determines an internal line by an intermittent tone (YES in step S6), and the received dial tone level is “−20 dBm” or more within a predetermined extension value range. In the case of (YES in step S7), it is determined as an extension and the process proceeds to the subsequent step S21. If step S7 is “NO” and the received line current value is outside the predetermined external line value range and less than 40 mA (NO in step S8), the majority is determined as an extension, and the process proceeds to the subsequent step S21. However, when the above step S8 is “YES”, the majority value cannot be determined because the current value is an external line in the dial tone regardless of the extension detection. For example, an abnormal alarm generation process that investigates the situation and takes measures. (Procedure S10) is performed.

  When the above step S6 is “NO” and not an extension in which the dial tone is intermittent, but a continuous sounding external line (YES in step S11) and the line current value is 40 mA or more within the predetermined external line value range (YES in step S12), The majority is determined as an outside line, and the process proceeds to the subsequent step S25. If the current value received in the above step S12 is “NO” and is less than 40 mA outside the predetermined external line value range (NO in step S13), it is determined that the line is an external line by majority, and the process proceeds to the subsequent step S25. However, when the above step S13 is “YES” and the dial tone level value is within the extension value range, since the outside line is detected by the dial tone, the majority decision cannot be made, and the procedure proceeds to the above step S10, for example, investigating the situation. An abnormal alarm is generated so that countermeasures can be taken.

  When the above step S11 is “NO”, it is impossible to identify the external line / extension line with the dial tone, the dial tone level is “−20 dBm” or more within the predetermined extension value range (YES in step S14), and the current value is within the predetermined external value range. If it is less than 40 mA outside (NO in step S15), the majority is determined as an extension, and the process proceeds to the subsequent step S21. When step S14 is “NO”, the dial tone level is less than “−20 dBm” outside the predetermined extension value range, and the current value is 40 mA or more within the predetermined extension value range (YES in step S16), the outside line is determined by majority decision. And the process proceeds to the subsequent step S25.

  When the above step S15 is “YES”, the dial tone level is “−20 dBm” or more within a predetermined extension value range, and the current value is 40 mA or more within a predetermined extension value range, and an abnormal state is expected to occur. Therefore, for example, an abnormality alarm generation process (procedure S20) is performed to investigate the situation and take countermeasures. If the above step S16 is “NO” and the level measurement value and the current measurement value cannot be distinguished from the external line / extension line, for example, the switching device is set so that the extension dial tone can be identified, and the telephone set is set accordingly. A countermeasure process (procedure S30) can be taken.

  The telephone control circuit 19 determines the use of the extension side sound balancing circuit 17-B by the extension determination of the majority by the outside line / extension setting function 20. When the telephone control circuit 19 receives from the side sound balance switching and holding circuit 17 that the setting of the extension side sound balance circuit 17-B is being held (YES in step S21), the telephone control circuit 19 receives the outside line / extension judgment setting function 20. The measured value is notified to the audio level adjustment circuit 18. The voice level adjustment circuit 18 adjusts the voice level for the receiver 15-A and the transmitter 15-B in the call circuit 14 (step S22). After the voice level is adjusted, the call circuit 14 connects the telephone line via the telephone line interface 12 and the hook switch circuit 11 to the receiver 15-A and the transmitter 15-B via the protection side sound circuit. (Procedure S23) to form a telephone line. As a result, the dial tone reaches the handset 15-A from the telephone line and can be listened to by the user, so the dial sending procedure (step S24) is executed.

  In step S23, the side tone balance circuit matches the connection line, and the sound level is adjusted, so that comfortable reception is ensured.

  The telephone control circuit 19 determines the use of the external line side sound balancing circuit 17 -A by the “external line determination” of the majority by the external line / extension setting function 20. When the telephone control circuit 19 receives from the side sound balance switching holding circuit 17 that the setting of the external line side sound balance circuit 17-A is being held (YES in step S25), the telephone control circuit 19 receives the outside line / extension determination setting function 20. The measured value is notified to the audio level adjustment circuit 18. The voice level adjustment circuit 18 proceeds to the above-described procedure 22 for adjusting the voice level for the handset 15-A and the transmitter 15-B in the call circuit 14.

  If the above step S21 or S25 is “NO” and the external line / internal line in the side tone balance circuit is set and held in reverse, the telephone control circuit 19 instructs the side tone balance switching holding circuit 17 to call the outside line. The setting of the side tone balancing circuits 17-A and B for the extension / extension line is switched (step S26) and is held. The dial tone level measurement circuit 22 and the line current measurement circuit 23 measure the dial tone level and the line current measurement value after switching (step S27) and notify the outside line / internal line determination setting function 20 so that the procedure is the measurement. It progresses to said procedure S22 which adjusts an audio | voice level based on a result.

  In the above description, the procedure has been illustrated and described sequentially, but the procedure may be performed in parallel or the order may be changed. In addition, in the three-party determination, even if there is a determination of both the outside line and the extension line, the decision is made according to the decision of one or more by majority vote. In this case, in addition to the determination operation, the situation may be displayed to the user or the installer.

  In the above description, the determination of the outside line / internal line is the majority decision. However, when the condition is increased, the ambiguous determination also increases, so it may be a majority. The majority in the case of the tripartite is more than two-thirds. Therefore, when the dial tone level at which the outside line / inside line cannot be determined is less than “−20 dBm” or the line current is less than 40 mA, the other determination is made. That is, for example, when the dial tone level is “−20 dBm” or more and less than 40 mA, the extension determination number is “2”.

  Since the configuration as described above is adopted, when making a call from a telephone by an off-hook operation, an external line / extension line is automatically and accurately identified by measuring the dial tone, dial tone level, and line current of the telephone line to be connected. it can. Thereafter, not only the side tone balance circuit adapted to the outside / inside line is connected, but also the sound level is adjusted, so that the sound level in the handset connected thereafter, particularly the handset, avoids sudden strong signal sound. Can be controlled. For example, when an external line is connected to an internal line with an external line setting, the line current is 20 mA or less in the internal line connection, so the conditions are the same as when the external line is connected to a long-distance station, and the level amplification is large. Therefore, when the extension is connected to the handset with the outside line set, the voice level will be very high, but such a situation can be avoided.

  The connected phone line is pulled into the telephone, and the multiple conditions are detected or measured, and the result is combined to identify the type of connected telephone exchange device. Since it can be selectively connected and the sound level can be adjusted from the measurement result, it is effective in forming an analog telephone circuit that can be connected to various existing telephone exchange devices.

It is explanatory drawing which showed one Embodiment of the telephone circuit by this invention with the block. It is explanatory drawing which showed one Embodiment of the first half of the main operation | movement procedures in the telephone circuit of FIG. 1 with the flowchart. It is explanatory drawing which showed one Embodiment of the second half of the main operation | movement procedures in the telephone circuit following FIG. 2A with the flowchart. It is explanatory drawing which showed an example of the conventional telephone circuit in the block. It is explanatory drawing which showed the example different from FIG. 3 of the conventional telephone circuit in the block.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Telephone 11 Hook switch circuit 12 Telephone line interface 13 Dial transmission circuit 14 Call circuit 15-A Handset 15-B Transmitter 16 Tone ringer circuit 17 Side sound balance switching holding circuit 17-A Outside line side sound balance circuit 17-B Extension Side tone balance circuit 18 Voice level adjustment circuit 19 Telephone control circuit 20 External / internal line determination setting 21 Dial tone type detection circuit 22 Dial tone level measurement circuit 23 Line current measurement circuit

Claims (6)

In the connection line type setting method for an analog telephone connected to an exchange device, when the telephone is connected to a telephone line, a plurality of conditions of the telephone line are detected, and the external line / The connection line type setting method for determining a connection line type of an extension and determining a type of an external line / extension based on the majority decision .
The plurality of conditions include the three types of the type of dial tone received when making a call from the telephone, the signal level of the dial tone, and the current value at the telephone line input terminal. For the extension or extension, the signal level and the current value when connected to the telephone line are set in advance for each of the external line and the extension, and when the call is sent from the telephone, the above three parties And determining whether or not to switch the side tone balance circuit from the current state based on the type of the external line / extension line determined from the condition including the connection line type. 2. The connection line type setting method according to claim 1 , wherein when the telephone determines the connection line type of the external line / internal line, a compatible side tone balance circuit is connected to the call line and the call current and transmission / reception are set according to the connection conditions. A connection line type setting method characterized by adjusting a voice level on a road to an appropriate value and connecting the telephone line to a telephone transmission / reception circuit. In the telephone circuit of an analog telephone connected to an exchange device,
A side balance circuit for external lines,
Side sound balance circuit for extension,
On the one hand, the external line side sound balance circuit and the internal line side sound balance circuit are connected to the call circuit on the other side, and upon receiving a balance circuit switching instruction, one of the external line side sound balance circuit and the internal line side sound balance circuit is connected. Side sound balance switching holding means connected to and held in the circuit;
Detecting and measuring means for detecting or measuring each of a plurality of conditions of a line including a dial tone and a line current inputted from the telephone line when connected to the telephone line and making a call from the telephone;
For each of the plurality of conditions of the telephone line, each condition for external line / internal line connected and held by the side tone balance switching holding means is set in advance, and the plurality of conditions are measured and set in advance when a call is made from the telephone. External line / extension type determination means for determining the external line / extension type under each condition,
When a call is made from a telephone, a plurality of external / internal line types determined by the external / internal line type determining means are received, and the external / internal line is determined by the majority decision, and the external / internal connection to the side sound balance circuit is determined. Control means for instructing the side tone balance switching holding means,
Equipped with a,
The external line / external line type determination means includes a plurality of line conditions that are received when a call is made from a telephone connected to the telephone line and received from the telephone connected to the telephone line. A telephone circuit comprising: a signal level of a dial tone; and a current value of a telephone line that flows to an input terminal when the telephone line is connected to the telephone line and is transmitted from the telephone. 4. The telephone circuit according to claim 3 , wherein the type of the dial tone is determined by detecting that a continuous tone is an external line and an intermittent sound is an internal line. 4. The telephone circuit according to claim 3 , wherein the external line / extension type determination means determines an external line when the current value is equal to or greater than a predetermined value or an internal line when the signal level is equal to or greater than a predetermined value. Telephone circuit. In the telephone circuit according to any one of claims 3 to 5, further speech level adjusting means for adjusting the transmitting / receiving respective audio level of the phone is transferred to the speech circuit receives the audio level adjustment instruction The control means obtains a voice level adjustment value from the measured values obtained from the dial tone level judgment means and the line current judgment means, outputs the adjustment instruction to the voice level adjustment means, and passes through the call circuit. And connecting the telephone line to a transmission / reception circuit.

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