JPH0223063B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention relates to an attached device to a telephone terminal, and particularly to a call time counting method that is effective when the reversal (polarity reversal) of a central office line cannot be detected as an attached device to a telephone terminal. It is something.

(2) Background of the technology In general, switching centers that accommodate subscriber lines, trunk lines, etc. are equipped with a lever sending function, and terminals and trunks monitor the levers and perform billing control processing by detecting polarity reversal. etc. are being carried out.

For example, as shown in FIG. 1B, a photocoupler installed in a telephone accessory equipment monitors the direct current of the office line (subscriber line). Normally, one wire L1 of a telephone line has a positive potential (ground) and the other wire L2
Since is at a negative potential, no current flows through the photodiode of the photocoupler. When the other party's telephone responds or the polarity of the telephone line is reversed for billing control, L1 becomes a negative potential and L2 becomes a positive potential, current flows through the photodiode, this photodiode turns on, and the collector potential V of the transistor decreases. do.

In addition, in polarity reversal from a state where L1 is a negative potential and L2 is a positive potential, that is, in polarity reversal for billing control, L1 is a positive potential and L2 is a negative potential,
No current flows through the photodiode, and the collector potential V of the transistor rises.

In this way, by monitoring changes in the collector potential V of the photocoupler transistor, it is possible to detect polarity reversal of the telephone line.

(3) Problems with the conventional technology The private branch exchange PBX shown in Figure 1a is
If the EX exchange and the private branch exchange PBX are connected by a subscriber line interface and the subscriber SUB is accommodated in the private branch exchange PBX, reverse monitoring detection is possible between the exchange EX and the private branch exchange PBX. On the SUB side, the private branch exchange PBX does not perform reverse relay, so it will not be detected even if monitored. However, typically subscribers within a private branch exchange PBX
When a SUB makes a call to a station, the reversal from the station is monitored on the trunk side within the PBX, so when billing per station line or per subscriber,
This is made possible by the control device within the PBX.

On the other hand, when using a telephone, a manually operated timer device or a counter connected to the telephone and automatically displayed is used as a device to easily count the call time and notify the user. . In the former type of timer device, the caller manually inserts a switch when the other party answers and stops at the end of the call to know the duration of the call, but the switch operation is cumbersome, and the latter's automatic display is A counting device has been proposed.

This automatic counting device starts counting the call time when it detects the reversal of the station line, stops when the reversal is reversed (recovered) or breaks the loop, and displays the counted value. be.

Therefore, if the reversal of the office line cannot be detected (for example, an extension subscriber connected to a PBX as shown in FIG. 1a), a problem arises in that the call time cannot be counted.

(4) Purpose of the Invention The purpose of the present invention is to solve such problems, and to make it possible to easily measure the call time even when the lever of the connected line cannot be detected in the telephone terminal etc. The purpose of the present invention is to provide a call time counting method that allows callers to be notified of the call time separately from billing processing.

(5) Structure of the Invention In order to achieve the above object, the present invention detects a DC loop in a line to which a telephone is connected in a telephone accessory device that has a function of counting talk time, and detects the off-hook/on-hook of this telephone. a loop detection means for detecting a dial signal sent from the telephone; a detection means for outputting a detection signal indicating completion of transmission of the dial signal by monitoring the dial signal sent from the telephone; A first counting means for outputting an output, and a second counting means for counting a call time from when activated by the timeout signal until it is reset by an on-hook detection signal of the loop detecting means, and a polarity reversal cannot be detected. Even if possible, the call time can be counted.

(6) Examples of the invention Hereinafter, the present invention will be explained in detail using examples. FIG. 2 is a schematic diagram illustrating the configuration of connected telephone accessories to which the call time counting method of the present invention is applied. Telephone terminal T is connected to the private branch exchange PBX,
The telephone terminal T consists of a telephone SUB and telephone accessory equipment E. In this embodiment, the telephone set and the telephone accessory equipment are shown separately, but the accessory equipment may be built into the telephone set.

FIG. 3 is a diagram illustrating the call time counting method of the present invention. In the method of the present invention, a call is made from a telephone terminal connected to a line where levers cannot be detected, dial DS is performed, and after the last dial D is sent out, a preset time (e.g., time considering exchange connection time; approximately 5 seconds) After the time has elapsed, the call time is counted in the same manner as when it is detected by levers, that is, as the start of a call.

FIGS. 4 and 5 are configuration diagrams of telephone accessory equipment to which the call time counting method of the present invention is applied. In the figure, L is the line loop (subscriber side loop) detection section, DS is the dialed digit detection section, RV is the reverse (PBX or EX side conversion) detection section, TC is the time counter, T is the call time counting section, and CTL. is a control section, and C is a loop or dial pulse detection circuit. When a subscriber SUB makes a call, a DC loop is formed in the subscriber line, and a DC current flows. This DC current is first detected by the loop detection section via the detection circuit C, detecting the calling of the subscriber SUB, and activating the dialed number detection section. Next, when the dial is turned, the dial number detector DS is detected via the detector C.
Detects the dial, and after detecting the final number, starts the reverse detector RV and starts the time counter.
Set the TC and count for a predetermined time. For example, in this embodiment, the counter counts for 5 seconds, and if the reverse detecting section detects reverse from the station EX or private branch exchange PBX during that time, the time counter TC is reset.
Activate the call time counter T. On the other hand, if reverse, which is the subject of the present invention, cannot be detected, the time counter TC will count for 5 seconds and time out.
Activate the call time counter T. The control unit reads the count value of the call time counting unit T during the call, displays it on a display (not shown), etc.
Display call duration to caller.

The telephone accessory device E of this embodiment may be controlled by a microcomputer, and the fifth
As shown in the figure, the present invention can be achieved by starting up each processing section from the control section and controlling the setting and resetting of the time counter TC and the call time counting section.

Note that the display of the call time count value is not limited to this embodiment, and the call time count value may be displayed all at once after the call time ends, and only the call time count result may be reported to the caller. Moreover, it is applicable not only to the talk time of a telephone, but also to the counting of data transfer time of a data terminal, etc., and also to the counting of time when a terminal device cannot detect a lever when using a data line.

(7) Effects of the Invention As explained above, according to the present invention, it is possible to easily know the duration of a call even when the line (office line) lever cannot be detected in a telephone terminal connected to a private branch exchange or a central office exchange. This will improve the service quality of telephone lines. In particular, it is possible to measure not only calls to the office line but also calls between internal lines, and there is no need to manually measure time by counting, etc., and the effect is extremely large.

[Brief explanation of drawings]

FIG. 1a is a schematic diagram of the configuration of a telephone exchange system to explain the technical background of the invention, FIG. 1b is an explanatory diagram of line lever detection, and FIG. 2 is a system explaining the call time counting method of the present invention. FIG. 3 is an explanatory diagram of the call time counting method of the present invention, FIG. 4 is a block diagram of the call time counting method of the present invention, and FIG. 5 is a flowchart of the process. L: Loop detection, DS: Dial number detection section,
RV: reverse detection unit, TC: time counter,
T: Call time counting section.

Claims (1)

[Scope of Claims] 1. A telephone accessory device having a function of counting call time, comprising: loop detection means for detecting a DC loop in a line to which a telephone is connected to detect off-hook and on-hook of this telephone; and this telephone. a first counting means that is set by the detection signal and outputs a timeout signal after a predetermined period of time has elapsed; a second counting means for counting the call time from when it is activated by a signal until it is reset by an on-hook detection signal of the loop detection means.