JPS6170895A - Key telephone system - Google Patents

Abstract

PURPOSE:To make sound volume adjusting operation unnecessary by making the amplifying gain of a speaker circuit at the time of a trunk line hand-free larger than the amplifying gain at the time of an extension hand-free. CONSTITUTION:A channel part 3 and a main control part to control the whole device are equipped with a main device 1. A button telephone device 4 is equipped with a hybrid circuit 9 connected to a terminal for sound, the first step mike amplifier part 6, a mike side sound switch part 7 and a later step amplifier part 8. The signal at the speaker side reaches a speaker 13 through the circuit 9, the first step speaker amplifier part 10, a speaker side sound switch part 11 and a later step speaker amplifier part 12. The amplifier part 10 is set to a gain variable state and this is controlled by a gain control part 15 based upon a signal given from a terminal 33 to a telephone set control circuit part 17.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a button telephone device. In particular, the present invention relates to a key telephone device equipped with a key telephone capable of making hands-free calls with substantially uniform voice capacity to a central office line and an extension line.

Here, the term "key telephone device" refers to a telephone that accommodates a small number of central office lines (including telephone central office subscriber lines and private branch exchange subscriber lines) and multiple extension lines, and that can be used to communicate between central office lines and extensions or extensions by button operation. A device used to make calls between A "hands-free call" refers to a call made using a speaker and microphone without using a handheld handset.

[Conventional technology]

In a button telephone device having a central office line and an extension line, the central line line loss is greater than the internal line line loss. For this reason, in a key telephone device having a function of making a hands-free call, when a hands-free call is being made, if the telephone is arbitrarily switched between the office line and the extension line, the volume of the speaker is reduced during the call over the office line.

For this reason, it has been necessary to increase the amplification gain of the speaker circuit of the hands-free circuit during telephone calls over the central office line.

However, in such cases, from a hands-free call on the central office line,
If you immediately switch to hands-free calling on an extension line, the gain will be too large, and the amount of noise going into the microphone will be greater than the speaker, resulting in poor call performance.

Therefore, at the time of this switching, the gain must be adjusted.

[Problem that the invention seeks to solve]

However, when this operation is performed, there is a pause in the progress of the hands-free call, so if the content of the call is urgent or delicate, information exchange between the callers cannot be carried out sufficiently. There are drawbacks.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks, and an object of the present invention is to provide a button telephone device that allows hands-free calls at a uniform volume, whether it is an internal call or a local office call. do.

[Means for solving problems]

The present invention is a button telephone device that can make hands-free calls to a central office line and an extension line, and is provided with a main control section in the main device that controls the entire device and detects the telephone call status of the central office line. The telephone is provided with a gain control section for controlling the gain of the speaker amplifier section, and a means for controlling the gain during a call on the central office line to be greater than the gain during a call on the extension line using a control signal from the main control section. It is characterized by:

That is, the present invention provides a central office line terminal for connecting a decimal number of central office lines, an extension terminal for connecting a plurality of extension lines, a communication line section for setting and connecting a communication path between the office line terminal and the extension terminals, and a telephone line terminal for connecting a plurality of extension lines. The key telephone device includes a main device including a main control section for controlling the telephone line section, and a button telephone device connected to the extension terminal, and the button telephone device includes a speaker circuit including a voice output amplification means and a voice output inch section. and a microphone circuit including an audio signal amplification means and an audio means switch section, the main control section has a button telephone device that determines whether the one button telephone device is in a central line call state or an extension call state. a call state identification means for identifying the call state, the amplification gain of the speaker circuit section is variably set, and the main control section is means for sending out a control signal for the amplification gain in accordance with an identification output of the call state identification means. The button telephone further includes means for controlling the amplification gain of the speaker circuit section using the control signal.

[Effect]

The gain of the speaker amplifier section is variably set by the main control section, and the main control section determines whether the call is between extension lines or not.
This gain is automatically controlled depending on whether the call is to a central office line or not.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings.

This drawing shows the configuration of the vehicle equipment W1 and the button telephone 4. In the main device l, a central office line is connected to a terminal 30, and a terminal 32
The key telephone 4 is connected to and 33. Although several button telephones 4 are generally connected, only one is shown here to simplify the explanation.

The main device 1 includes a communication path section 3 and a main control section 2 including a microprocessor that controls the entire device.

A hybrid circuit 9 is connected to a voice terminal 32 of the button telephone device 4 . The output of the microphone 5 is input to this hybrid circuit 9 via a first-stage microphone amplifier section 6, a microphone-side audio switch section 7, and a second-stage amplifier section 8. The signal on the speaker side is transmitted from the hybrid circuit 9 to the first stage speaker amplifier section 10 and the speaker side audio switch section 1.
), the speaker 13 via the rear speaker amplifier section 12
reach.

Both audio switches 7 and 1) are connected to the audio switch control unit 1
Controlled by 4. This circuit is known.

Here, the feature of the present invention is that the first stage speaker amplifier section 10 is set to have a variable gain, and this is controlled by the gain control section 15 based on a signal given from the terminal 33 to the telephone control circuit section 17.

Next, the operation of the embodiment will be explained.

Currently, the operator is using a key telephone with a hands-free function 4
This section explains how to make a hands-free call using an extension. The transmitting audio signal from the voice emitted by the operator is sent to the terminal 31 via the first-stage microphone amplifier section 6, the microphone-side audio switch section 7, the second-stage microphone amplifier section 8, the hybrid circuit 9, the audio terminal 32, and the communication path section 3. It is sent to the key telephone (not shown) of the other party to be connected.

On the other hand, the audio signal from the other party's key telephone is transmitted via the terminal 31 to the communication line section 3, the hybrid circuit 9, the first stage speaker amplifier section 10, the speaker side audio switch section 1) and the second stage speaker amplifier section 12 to the speaker. 13, the sound is amplified and output. Here, voice switch control section 1
4 compares the levels on the transmitting side and the receiving side and controls the microphone side audio switch section 7 and the speaker side audio switch section 1) in order to prevent howling.

When in such an extension hands-free call state, the main control section 2 sends a signal to the telephone control circuit section 17 indicating that the key telephone 4 is in the extension hands-free call state. The telephone control circuit section 17 receives this signal and
The gain control section 15 is controlled to set the gain of the first stage speaker amplifier section 6 to a low gain suitable for an extension hands-free call.

On the other hand, when the key telephone 4 is in a hands-free talking state with respect to the central office line, the main control section 2 sends a signal to the telephone control circuit section 17 indicating that the key telephone 16 is in a hands-free talking state with respect to the central office line. Send. Telephone control circuit section 17
Upon receiving this signal, the gain control unit 15 is controlled to set the gain of the first stage speaker amplifier unit 10 to a high gain suitable for central office line hands-free communication. The gain for the extension hands-free call and the gain for the office line hands-free call are set in advance in the gain control unit 15.

〔Effect of the invention〕

As explained above, the present invention automatically controls the amplification gain of the speaker circuit during the temporary hands-free call to the central office line to be larger than the amplification gain during the temporary hand-free call to the extension line, thereby distinguishing between the central office line call and the extension call during the hands-free call. Since almost the same volume can be obtained even if the volume is switched arbitrarily, there is no need to adjust the volume, and continuous calls can be made, which is highly effective in exchanging information between callers.

[Brief explanation of the drawing]

The drawing is a block diagram of essential parts of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Main device, 2... Main control part, 3... Call path part, 4... Button telephone, 5... Microphone, 6...
... First stage microphone amplifier section, 7... Microphone side audio switch section, 8... Second stage microphone amplifier section, 9... Hybrid circuit, 10... First stage speaker amplifier section, 1)...
-Speaker side audio switch unit, 12...Late stage speaker amplifier unit, 13...Speaker, 14...Audio switch control unit, 15...Gain control unit, 16...Operation unit,
17... Telephone control circuit section, 30... Office line connection terminal, 31... Terminal, 32... Audio terminal, 33...
・Data signal input/output terminal.

Claims (1)

[Claims] (1) A central office line terminal that connects a decimal number of office lines, an extension terminal that connects a plurality of extension lines, a communication line section that establishes and connects a communication path between this office line terminal and the extension terminal, and this communication path. a key telephone device controlled by the extension terminal; the button telephone device includes a speaker circuit including an audio output amplifying means and an audio output switch section; , a key telephone device equipped with a microphone circuit including an audio signal amplification means and an audio signal switch section, the main control section being configured to indicate whether one button telephone device is in a central line call state or an extension call state. The main control unit includes means for identifying a call state, wherein the amplification gain of the speaker circuit section is variably set, and the main control section includes means for transmitting a control signal for the amplification gain in accordance with an identification output of the call state identification means. A button telephone device, further comprising: means for controlling the amplification gain of the speaker circuit section in accordance with the control signal.