JPH0537571Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) The present invention relates to a telephone or telephone device (switchboard, button telephone device, etc.) having a so-called on-hook dialing function that allows you to make a call without lifting the handset. The present invention relates to a signal emission level adjustment circuit for optimally setting the emission level of various signal tones from speakers.

(Prior art and its problems) A telephone with an on-hook dialing function closes a DC loop to the communication path of the line by pressing the on-hook button instead of lifting the handset, and connects the communication path to the speaker. The telephone is connected to a high-pitched voice circuit, and is configured to emit dial tone, ring back tone, and voice from the other party from the speaker.
Incidentally, the telephone set is normally configured so that an incoming call can be answered by pressing the on-hook button without lifting the handset.

As shown in FIG. 3, when a telephone with an on-hook dialing function, for example, a button telephone TEL _A , calls a telephone TEL _B belonging to a telephone exchange CO _{2 different from the telephone exchange CO 1 to} which the button telephone TEL _A belongs. Considering that, after pressing the on-hook button on the button telephone TEL _A , the corresponding button telephone TEL _A
The dial tone received by the button telephone TEL A and the ring back tone received by the button telephone TEL _A while calling the telephone TEL _B after dialing on the button telephone TEL _{A are}
It is sent from the signal transmitter SIG of the telephone exchange CO ₁ to which it belongs. On the other hand, after the called telephone TEL _B responds, the voice emitted by the called party is transmitted to the switching station to which the telephone TEL _B belongs.
CO ₂ and the exchange office to which key telephone TEL _A belongs CO ₁
The message is sent to the corresponding key telephone TEL _A via . Therefore, the dial tone and ring back tone are subject to loss due to the subscriber line l ₁ of the key telephone TEL _A , whereas the called party's voice is lost between the subscriber line l ₁ and the telephone exchanges CO ₁ and CO _2. relay circuit
Loss is caused by l ₂ and telephone TEL _B 's subscriber line l ₃ . Therefore, as shown in Figure 4, the dial tone and ring back tone are sent to the button telephone _{TEL A} at level b, which is much higher than the call voice level a. If the tone and ringback tone are emitted at a louder volume than the voice of the call, and the level of the voice emitted from the speaker is adjusted to match the dial tone and ringback tone, the voice of the call will be lower, and vice versa. There is a problem that the dial tone and ring back tone become too loud.

(Purpose of the present invention) The present invention has been made to solve the above-mentioned problems. Another object of the present invention is to obtain a signal sound emission level adjustment that can always maintain an appropriate level regardless of the type of sound.

(Summary of the present invention) For the above purpose, the present invention sets two types of level loss in the signal input path to the speaker, and configures a circuit to switch the level loss according to the response of the called party. did.

(Embodiments of the present invention) Figures 1 and 2 are block diagrams showing first and second embodiments in which the present invention is implemented in a button telephone device, where ME is the main device and TEL is the on-hook dial function. This is a button telephone (hereinafter referred to as a telephone) equipped with a.

In the main device ME, TRK is an external line trunk,
For example, a central office line trunk (hereinafter, a central office trunk is taken as an example), RT is a called party response detection section of a central office trunk TRK, IOT is an extension trunk, and AT is a level adjustment means, such as a resistor (hereinafter, a resistor). For example),
SW is a short-circuit switch for resistor AT, telephone TEL
In the above, HS is a switch, NW is a communication network, AT ₁ and AT ₂ are level adjustment means, such as a variable resistor (hereinafter, variable resistor is taken as an example), SW ₁
is the line closing switch when operating the on-hook dial, SW ₂ is the changeover switch for the receiving route, SW ₃ is the changeover switch for variable resistors AT ₁ and AT ₂ , K is the operation button for on-hook dialing, and AMP is the operation button for making an on-hook dial call. amplifier, SP is the speaker, CPU is the processor, T
is a transmitter, and R is a receiver.

A first embodiment will be explained with reference to FIG.

The variable resistors AT ₁ and AT ₂ are provided as means for adjusting the volume of the telephone, and can be operated by the user of the telephone TEL. Now, variable resistor
It is assumed that the level loss due to AT ₁ is set larger than the level loss due to variable resistor AT ₂ .

In order to make an on-hook dial call to a central office line using the telephone TEL, after selecting the central office line, press operation button K. The processor CPU detects this and closes switch SW ₁ , in the same way as when closing switch HS. , performs control to close a DC loop to the office line within the office line trunk TRK. In parallel with this, the processor CPU controls switch SW ₂ to change the receiving path from the receiver R to the speaker.
Switch SW 3 to the SP path side and maintain the switch SW ₃ on the variable resistor AT ₁ side with large loss (when the steady state is on the variable resistor AT ₂ side,
Switch to AT ₂ side. ).

The above state continues until the user of the telephone TEL dials and the called party (TEL _B shown in FIG. 3) answers. Therefore, the dial tone and ringback tone sent from the affiliated telephone exchange (CO ₁ shown in Figure 3) to the telephone TEL, the telephone TEL
The dialback tone sent out from the dial circuit (not shown) is input to the amplifier AMP via the variable resistor _AT1 with the larger loss, and is emitted from the speaker SP. Therefore, the dial tone, ring back tone and dial back tone are emitted from the speaker SP with a relatively large loss (ie, at a level that is relatively significantly lower than the level received at the telephone TEL).

When the called party TEL _B responds, response information is sent from the telephone exchange to which the called party TEL _B belongs (CO ₂ shown in Figure 3) to the main device ME via the telephone exchange CO ₁ .
In the main equipment ME, the called party response detection section RT of the central office line trunk TRK detects the above response information, and the telephone TEL
The detected response information is input to the processor CPU.

In response to the response information, the processor CPU controls the switch SW ₃ to switch the input of the amplifier AMP to the variable resistor AT ₂ , which has a smaller loss. This allows the transmitted audio from the called party TEL _B to be sent to the speaker SP with relatively little loss (i.e., at a level not much different from the level received at the telephone TEL).
More sound is emitted.

As a result of the above, the dial tone, ringback tone, and dialback tone input to the telephone TEL at a high level are greatly attenuated and amplified.
The transmitted voice of the called party, which is input to the AMP and then input to the telephone TEL at a low level, is input to the amplifier AMP without being attenuated much, so both speakers SP output the sound at an appropriate volume. You can do it like this.

Note that calls between telephones housed in the main device ME, that is, telephones TEL A and TEL _A shown in FIG.
Calls between TEL _C are carried out via the extension trunk IOT, but when making on-hook dial calls during these calls, there are cases where there is a high loss as in the outgoing voice from the called party. Therefore, switch SW ₃ is located on the variable resistor AT ₁ side, which has a large loss, and will not switch.

Next, a second embodiment will be described with reference to FIG.

The second embodiment is an example in which level switching is performed within the main device ME when a called party responds to an on-hook dial call. In other words, a resistor AT is inserted into the communication line between the telephone TEL and the office line trunk TRK, and a switch SW is connected to both ends of the line, and when the called party responds, the signal is sent from the called party response detection unit RT. The response information is used to close the switch SW and short-circuit the resistor AT, thereby performing level switching.

If the level switching control is performed within the telephone as in the first embodiment, the system can be directly accommodated in the telephone exchange without intervening equipment such as the main device ME. The present invention can also be implemented in a so-called standalone telephone.

In addition, public address telephones (hands-free telephones) are
Since it essentially has an on-hook dialing function, the present invention can also be implemented in the loudspeaker telephone.

(Effects of the Present Invention) As is clear from the description of the embodiments above, the present invention has the effect that the sound level emitted from the speaker during on-hook dialing is always maintained at an appropriate level.

[Brief explanation of the drawing]

1 and 2 are block diagrams of an embodiment of the present invention, and FIGS. 3 and 4 are block diagrams and signal level diagrams of a telephone switching network for explaining the technical background of the present invention.

Claims (1)

[Scope of utility model registration request] 1 inserted in the signal input path to the speaker in a telephone device with an on-hook dial function.
level adjustment means, or two level adjustment means with different attenuation amounts.
A switch that operates according to the called party response information sent from the outside line when making an outside line call and short-circuits the one level adjustment means or switches between the two level adjustment means. 1. A signal tone emission level adjustment circuit comprising means for adjusting a signal tone emission level from a speaker before receiving called party response information to be lower than the signal tone emission level after receiving called party response information.