JPH0495492A - On-hook signal sending-out circuit - Google Patents

Abstract

PURPOSE:To decrease the number of control signals required to send an on-hook signal out and the number of switches such as relays required for the transmission to a fraction of the number by generating the on-hook signal at the operation timing of a 1st switch and a 2nd switch. CONSTITUTION:A ringer oscillator 41 sends an incoming signal to the movable contact 60a of a relay 60 continuously. Once the incoming is detected, the common contact 34a and contact 34c of a relay 34 are connected and the incoming signal is supplied to an analog terminal 31, so that a display based upon the incoming signal is made on the display unit of the terminal 31. When the terminal 31 responds to the incoming at time t11, the contact is switched to the side of a contact 34b to supply a DC current from a DC supply circuit 37 to the terminal 31. When the handset is placed on the hook at time t12, the contact 34a of the relay 34 is switched to the side of a contact 34c for a constant time according to a specific control signal and the relay 60 is broken instantaneously for a constant time, so that the on-hook signal which is in the constant time wherein no DC current is supplied is supplied to the terminal 31.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a call clearing signal sending circuit having a relatively simple configuration and applied to a telephone exchange device such as a button telephone device or a switchboard to which analog terminals are connected.

Conventional technology Conventionally, some analog terminals have a function of automatically terminating the operation of their own communication/calling circuit by a signal sent from the line when the other party who is communicating or talking through the line ends the call. . A DC loop instantaneous interruption signal is sent from this line as a notification signal (hereinafter referred to as a call end signal) of the call end of the other party.

FIG. 3 shows the configuration of a conventional call termination signal sending circuit.

In FIG. 3, l is an analog terminal, which is connected through a terminal 3 to a common contact 4a of a relay 4 with two contacts per circuit, and is also connected through a terminal 5 to one end of a capacitor 6 and a DC supply circuit 7. . A contact 4b is connected to the DC supply circuit 7 and one end of the capacitor 8. A negative terminal of the DC supply circuit 7 is grounded through a relay 9. The other ends of the capacitor 6 and the capacitor 8 are connected to a communication transformer 10. 11 is a ringer oscillator that sends the incoming signal to contact 4c of relay 4 and relay 1.
It is supplied to contact l2C of No. 2.

Reference numeral 2 designates an analog terminal, which is connected to the common contact 12a of the two contacts 1 and -12 of one circuit through the terminal 5, and is also connected to one end of the capacitor I7 and the DC supply circuit 18 through the terminal 16. A contact 12b is connected to one end of the DC supply circuit 18 and the capacitor 19. The negative terminal of the DC supply circuit 18 is connected to the relay 20
is grounded through. The other ends of capacitor J7 and capacitor 19 are connected to communication transformer 21.

Next, the operation of the above conventional example will be explained based on the timing chart shown in FIG.

As understood from FIG. 4(a), the ringer oscillator 1
1 continuously sends the incoming signal to the contacts 4c and 1 of relays 4 and 12.
It is sent to 2c. When an incoming call is detected, the common contact 4a and the contact 4c of the relay 4 are connected (see FIG. 4(b)), an incoming call signal is supplied to the analog terminal I, and the display of the analog terminal I (not shown) is connected. (Figure 4)
d)). Then, at time tl, analog terminal 1
When responds to the incoming call, DC current is supplied from the DC supply circuit 7 through the relay 4 contact 4b and the common contact 4a. When the call ends at time 12, the relay 9 is momentarily disconnected for a certain period of time (time between time t2 and time t3) based on a specific control signal, and a call end signal is supplied to the analog terminal 1 (Fig. 4). (See (C)).

A call termination signal is also supplied to the analog terminal 2 through a similar operation (see FIGS. 4(e) to 4(g)).

In this way, the conventional end-of-call signal sending circuit can also send out the end-of-call signal.

Problems to be Solved by the Invention However, in the conventional call termination signal sending circuit described above, in order to send a call termination signal to one analog terminal 1 or analog terminal 2, an independent relay 9 or relay is used in addition to relay 4 and relay 12. 20 and an independent control signal for controlling it, which resulted in a problem that the circuit configuration became complicated.

The present invention solves these conventional problems by making it possible to generate a call termination signal by using a single control signal and a relay for transmitting an incoming signal, which is originally provided in each terminal. The object of the present invention is to provide an excellent call termination signal sending circuit.

Means for Solving the Problems In order to achieve the above object, the present invention includes a first switch that passes or blocks an incoming signal sent from a ringer oscillator, and a direct current supply circuit that is connected to the first switch. and a second switch that switches between the DC current supplied from the DC supply circuit and the output signal of the first switch.

Operation Since the present invention is configured as described above, by generating a call termination signal according to the operation timing of the first switch and the second switch, a call termination signal is generated to the analog terminal connected to the second switch. The number of control signals required for signal transmission and the number of switches such as relays required for transmission can be reduced to several times.

Embodiment FIG. 1 shows the configuration of an embodiment of the present invention. In FIG. 1, 31 is an analog terminal, which is connected through a terminal 33 to a common contact 34a of a relay 34 (second switch) with 1 circuit and 2 contacts, and through a terminal 35 to one end of a capacitor 36 and to the DC supply circuit. It is connected to 37. A contact 34b is connected to one end of the DC supply circuit 37 and the capacitor 38. The other ends of the capacitor 36 and the capacitor 38 are connected to a communication transformer 40. 4] is a ringer oscillator, which sends out an incoming signal. Reference numeral 60 denotes a relay (first switch) with one circuit and one contact, which allows the incoming signal sent from the ringer oscillator 41 to pass through or connects or disconnects through the movable contact 60a.

The contact 60b of this relay 60 is the contact 34c of the relay 34.
and a contact 42c of a relay 42 with one circuit and two contacts is connected.

32 is an analog terminal, which connects relay 4 through terminal 45.
2, and is connected to one end of the capacitor 47 and the DC supply circuit 48 through the terminal 46.
It is connected to the.

42b is a contact, which connects the DC supply circuit 48 and the capacitor 4.
It is connected to one end of 9. The other ends of the capacitor 47 and the capacitor 49 are connected to the communication transformer 5.

Next, the operation of the above embodiment will be explained based on the timing chart shown in FIG.

As understood from FIG. 2(a), the ringer oscillator 4
1 continuously supplies an incoming signal to the movable contact 60a of the relay 60. When an incoming call is detected, the common contact 34a and the contact 34c of the relay 34 are connected (see FIG. 2(b)).
, the incoming signal is supplied to the analog terminal 3I, and a display based on the incoming signal is displayed on the display (not shown) of the analog terminal 31 (see FIG. 2(d)). And time tl+
When the analog terminal 3I responds to the incoming call (see FIG. 2(d)), the common contact 34a of the relay 34 is switched to the contact 34b side, and the DC current is supplied from the DC supply circuit 37 to the analog terminal 31 through the relay 34. Supplied through. When the call ends at time t12, the common contact 34a of the relay 34 switches to the contact 34C based on a specific control signal.
side for a certain period of time (time between time t12 and time tla, second
(see figure (C)), and the relay 60 is switched for a certain period of time (from time t12 to time t) 3 (see figure 2).
b)) Due to the instantaneous interruption, a call end signal (see FIG. 2(d)), which is a signal for a certain period of time during which DC current is not supplied, is supplied to the analog terminal 31 (see FIG. 2(d)). .

A call termination signal is also supplied to the analog terminal 32 in a similar manner (see FIG. 2(e)).

In this way, according to the above embodiment, a so-called end-of-call signal, which instantaneously interrupts direct current, can be supplied to an analog terminal using a smaller number of relays than in the conventional example, so the circuit configuration is relatively simple. .

Furthermore, the number of control signals is also reduced.

Note that in this embodiment, when the call termination signal is sent (for example, at time t12), the control signal first causes
The relay 60 becomes open, and then the common contact 34a of the relay 34 switches to the contact 34C side. On the other hand, at the end of the call termination signal (time tla), the control signal first switches the common contact 34a of the relay 34 to the contact 34C side. It is preferable to select the relays 60 and 34 so that the contact 34a switches to the contact 34b side and then the relay 60 becomes connected.

Effects of the Invention As is clear from the embodiments described above, the present invention generates a call termination signal based on the operation timing of the first switch and the second switch, thereby transmitting a call to the analog terminal connected to the second switch. This has the effect that the number of control signals required to send out a call termination signal and the number of switches such as relays required for sending out can be reduced to several times. .

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram of a call termination signal sending circuit according to an embodiment of the present invention, FIG. 2 is a timing chart for explaining the operation of the call termination signal sending circuit shown in FIG. 1, and FIG. 3 is a conventional circuit diagram. A schematic circuit diagram of the end-of-call signal sending circuit, and FIG. 4 is a timing chart for explaining the operation of the end-of-call signal sending circuit shown in FIG. 31.32...Analog terminal, 34.42...Second
switch, 37.48... DC supply circuit, 41...
・Rin is the oscillator, 60...first switch. f) Hell agent Patent attorney Shigetaka Awano and others

Claims (1)

[Claims] a direct current supply circuit that sends out a direct current; a ringer oscillator that sends out an incoming signal; a first switch that is connected to the ringer oscillator and passes or blocks the incoming signal that is sent out from the ringer oscillator; A call termination signal sending circuit comprising: a second switch connected to the circuit and the first switch to switch between a direct current supplied from the direct current supply circuit and an output signal of the first switch.