JPS59198073A - Power supply system of metering pulse receiving circuit - Google Patents

Abstract

PURPOSE:To avoid ineffective consumption of power at connection of incoming call by applying a power supply voltage to a metering pulse receiving circuit only at a trunk line calling connection. CONSTITUTION:A metering pulse receiving circuit MPR and a power supply switch PSW are connected to a trunk line CL. The circuit MPR receives the metering pulse arriving from the trunk line CL, outputs charging information (m) and transmits it to a central controller CC via a scanner SCN. The controller CC activates the switch PSW so as to supply power to the circuit MPR when a detecting signal (l) outputted from a loop detecting circuit LD without receiving a detecting signal (r) outputted from a call signal detecting circuit RD.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to an automatic private branch exchange, and particularly to a power supply system for a billing pulse receiving circuit that receives billing pulses arriving from a central office line during an outgoing telephone call. about.

fbl Background of the technology In a telephone exchange, a billing pulse of, for example, 12 kilohertz or 16 kilohertz is sent for the purpose of notifying the calling subscriber of the call rate during a call, and a rate meter installed in the subscriber's premises is activated. The method is known. Even in automatic private branch exchanges, for example, attempts have been made to provide a billing pulse receiving circuit for receiving the billing pulse in a central office line trunk, and to collect billing information for central office line origination connections.

(C1 Prior Art and Problems Fig. 1 is a diagram showing an example of a power supply system for a conventional charging pulse receiving circuit in a central office line trunk. In Fig. 1, a charging pulse receiving circuit MPR is connected in parallel to the central office line CL. is connected to the capacitor C through the low-pass filter LPF.
A calling signal receiving circuit made up of I and a calling signal detection circuit RD, and a DC loop circuit made up of an occlusion line RET and a loop detection circuit LD are connected. The ringing signal detection circuit RD detects the ringing signal arriving from the central office line CL when a call arrives on the central office line, outputs a ringing signal detection signal r, and transmits the signal to a central control unit (not shown) via the scanning device SCN.

The loop detection circuit Li) detects the DC loop current supplied from the office line CL when an extension call is connected to the office line or when an extension subscriber responds to an incoming call from the office line, outputs a loop detection signal l, and performs scanning. via the device SCN to said central control unit.

Note that the loop detection signal 1 also energizes the power switch PSW, causing the power supply voltage V to be supplied to the billing pulse receiving circuit MPR. The billing pulse receiving circuit MPR is connected to the central office line C during a telephone call originating from the central office line.
It receives said charging pulse arriving from L and outputs charging information m and transmits it to said central control unit via a scanning device SCN. The central control unit calculates the number of telephone calls originating from the central office line from the transmitted billing information m, and grasps the call charges. Note that the billing pulse is prevented from flowing into the extension side by the low-pass filter LPF.

As is clear from the above explanation, in the conventional power supply system of the billing pulse receiving circuit, the power switch PSW is energized by the loop detection signal 1, so billing pulses arrive not only when the central office line is connected, but also when the billing pulse arrives. Even when an incoming call is connected to a central office line without a charger, the power supply voltage V is supplied to the billing pulse receiving circuit MPH, which has the disadvantage of ineffectively consuming power.

(dl) Purpose of the Invention The purpose of the present invention is to eliminate the drawbacks of the conventional power supply system of the billing pulse receiving circuit as described above, and to realize a means for preventing ineffective consumption of power in the billing pulse receiving circuit as much as possible. .

tel Structure of the Invention The object of the present invention is to provide an automatic private branch exchange equipped with a charging pulse receiving circuit that receives charging pulses arriving from a central office line when a central office line is connected to a central office line, and a switching element that supplies operating power to the charging pulse receiving circuit. This is achieved by providing means for detecting that a central office line origination connection is established via the central office line and energizing the switching element.

(f) Examples of the invention An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram showing a power supply system for a charging pulse receiving circuit according to an embodiment of the present invention. Note that the same reference numerals indicate the same objects throughout the figures. In FIG. 2, a power switch PSW that supplies a power supply voltage V to a billing pulse receiving circuit MPH receives a loop detection signal l outputted from a loop detection circuit LD in both cases of connection to a central office line and connection to a central office line. In some cases, it is not energized. The central controller CC is the first
As in the figure, when an incoming call is connected to a central office line, after receiving the ringing signal detection signal r outputted from the ringing signal detection circuit RD via the scanning device SCN, the loop detection signal 1 outputted from the loop detection circuit LD is scanned. The loop detection signal l outputted from the loop detection circuit LD is received via the scanning device SCN without receiving the ringing signal detection signal r when connected to a central office line.

Therefore, if the central controller CC receives the loop detection signal l without receiving the ringing signal detection signal r from the central office line trunk, it determines that an outgoing connection has been set up on the central office line CL, and sends the call signal via the signal distribution device SD. and transmits the central office line transmission information S to the central office line trunk. In the central office line trunk, the power switch PSW is energized by the central office line transmission information S, and supplies the power supply voltage V to the billing pulse receiving circuit MPR. Thereafter, the charging pulse receiving circuit MPR receives charging pulses arriving from the central office line CL during a call originating from the central office line, and sends the charging information m to the scanning device SCN.
to the central control unit CC. When the central office line outgoing call is completed, the DC loop circuit is opened and the loop detection circuit LD stops outputting the loop detection signal l. The central controller CC detects the end of the local line originating call from the stop of the loop detection signal l, and stops transmitting the local line originating information S to the central office line trunk. In the central office line trunk, when the central office line transmission information @s is stopped, the power supply switch PSW stops supplying the power supply voltage (■) to the billing pulse receiving circuit MPH. On the other hand, if the central control unit CC receives the loop detection signal l after receiving the ringing signal detection signal r from the central office line trunk, it determines that an incoming connection is set on the central office line CL, and the central control unit CC outputs the central office line origination information S. do not.

Therefore, when an incoming call is connected to the central office line, the charging pulse receiving circuit MPR is not supplied with the power supply voltage (2).

As is clear from the above explanation, according to the present embodiment, the billing pulse receiving circuit MPR is connected to the power supply voltage V only when the office line transmission is connected.
This avoids ineffective consumption of power when connecting incoming calls to the central office line.

Note that FIG. 2 is only one embodiment of the present invention, and for example, the central office line transmission information S is not limited to that transmitted from the central control unit CC, and for example, the central office line transmission information S is not limited to that transmitted from the central control unit CC. Although many modifications may be made to the provision of means for identifying incoming and outgoing calls, the effects of the present invention remain the same in any case. Further, the billing pulse receiving circuit MPR is not limited to being installed within the central office line trunk, and may be installed independently of the central office line trunk, but the effects of the present invention will not change even in such a case.

(g) Effects of the Invention According to the present invention, in the automatic private branch exchange, the billing pulse receiving circuit is prevented from consuming power ineffectively when an incoming call is connected to the central office line, and this contributes to power saving in the automatic private branch exchange. effective.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a power supply system for a conventional charging pulse receiving circuit, and FIG. 2 is a diagram showing a power supply system for a charging pulse receiving circuit according to an embodiment of the present invention. In the figure, C1 and C2 are capacitors, CC is the central control device, CL is the station line, LD is the loop detection circuit, and LP
F is a low-pass filter, MPR is a billing pulse receiving circuit, NW is a network, PSW is a power switch, RD is a ringing signal detection circuit, RET is a blockage wire, SCN is a scanning device, and SD
is a signal distribution device, T is a transformer, ■ is a power supply voltage, ■ is a loop detection signal, m is billing information, r is a ringing signal detection signal, S
indicates central line transmission information.

Claims (1)

[Claims] In an automatic private branch exchange equipped with a charging pulse receiving circuit that receives charging pulses arriving from the central office line when a central office line is connected, the switching element includes a switching element that turns on operating power to the charging pulse receiving circuit, and a switching element that connects the central office via the central office line. A power supply system for a billing pulse receiving circuit, comprising means for detecting that a line transmission connection is set and energizing the switching element.