JPS5890894A - Main wire interface circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Kinoha automatically identifies the station-〇 polarity so that the processing of the private branch exchange is not affected by the connection a of the branch office line, and the six-station line interface Ojiro l1cw4 It is something to do.

There are two methods for activating the exchange from the subscriber side: the ground start method and the loop start method. In both cases, exchange connection information is lost depending on the presence or absence of subscriber line potential, the direction of current, etc. . Also, the polarity of the subscriber line is called the Tsu/Sorimata Al X-ray, and is broadly defined in accordance with the information on the jump with the exchange. Private branch exchange (PIIK)
is generally treated as the same as a regular subscriber by the exchange, and is called the subscriber-extension line of this pigeonhole, and this station! 14, its role is defined depending on its polarity.

The electrical interface between such a private branch exchange/machine and the switching center is very effective in terms of equipment design and design, but from the point of view of installation work and maintenance, it is There is the inconvenience of having to take polarity into account when making connections or inspections, and if the connection polarity is incorrect, it will be considered a failure and the service will be interrupted until the correct connection is made. .

Kinoto Ipeng improved the above-mentioned shortcomings and made a major change to the station line ma.
The purpose of this invention is to detect station-○Ii characteristics and automatically perform switching control so that installation work and inspection work can be performed without considering the characteristics. Examples will be described in detail below.

The present invention provides a means for detecting the polarity of the office line, and switches the polarity of the station drawn into the private branch exchange so that it is always constant, or switches the enclosure for detecting the ground air sent to the office line. It is something.

Figure 1 is a circuit diagram of the main part of the embodiment of the present invention, 81~R
3 is a resistor, C1 to C5 are capacitors, Dl is a diode, 91 to Q4 are transistors, and RL is a relay,
Central line L1. L2 polarity detection circuit [configured]. Also T,
R is the chip (7') connected to the trunk of the private branch exchange.
p) line and ring (Etsg) line, deL is relay EL
This is the point of contact. Regarding the AlB wire, the A wire corresponds to the ring IiR, and the B11 corresponds to the tip @T.

9. Resistors 81 to B5 should be of high resistance so as not to affect the game signal or the communication TmJ@ signal. The relationship is selected such that R1-R2<85. Further, the capacitor Cs is connected in parallel with the relay ML and acts as a slow recovery for the relay EL.

Station line L1 is the chip line, station #! If L2 is connected to the exchange through a ring line, the battery (usually -48V) is sent from the expansion exchange to the ring line in an idle state, and the tip line is open or grounded. , when the chip line is open, the terminal l1IL2 is connected via the resistor R5+E2f.
When a small current flows through the chip line and the chip line is grounded, the central line L
1. A minute current flows through the L2 cabinet. However, each of the resistors R1 to R3 is selected to have a high resistance so that the switching office does not operate due to this minute current.

As mentioned above, if the station line L2 is a battery, the transistor Q1
．． Q! This is a state in which no base current flows.

Therefore, transistors Q1 to Q4 are in the off state and relay RL
does not operate, so the contact point D is in the state shown in the figure.

That is, the connection state is Ll-'I' and Ll-H.

Furthermore, when the battery is sent to the station @L1, the base current of the transistor Q1 flows through the resistor je1, so that the base current of the transistor Q1. Q2 becomes on-state.

Furthermore, even if the terminal @L2 is open or grounded, the base current of the transistor QS flows through the resistor R5 or the resistor E2°Rs9, and the transistors Qji and Q4 are turned off. Therefore, relay EL operates and contact fjl
Due to the switching operation, In, Z, 1-E, and In2-T are connected. That is, the tip line T and ring line R on the private branch exchange side are the 1-station line L1. Regardless of the polarity of L2, the polarity is switched and connected so as to have a constant polarity.

Figure 2 is an explanatory diagram of the sequence when a call is received from the exchange CO to the extension subscriber of the private branch exchange PBX (To4), OPN is loop open, CLS is loop closed, R-G beam/Goo-Guf/Do% T-G indicates the tip line ground, R←B indicates the ring line battery, T-J indicates the chip line battery, T-OPN indicates the chip line open, and the solid line indicates the ground start method and the point mu loop start method.

In the idle state, the ground start method leaves the tip line open and the ring wire battery connected, while the loop start method leaves the tip line grounded and the ring wire battery disconnected.

When a call arrives at the exchange CO, the exchange CO sets T←B, R4-G to the central office line, and performs ringing.

The private branch exchange PBX identifies the incoming call through these detections, and performs a loop opening CLS as an answer ANTI.

The exchange CO detects the response ANS due to loop closure and forms a communication path. In the case of recovery from the exchange CO, the caller sends a busy tone BT by on-hook and restores to the idle state, or the private branch exchange FBI sends a busy tone BT by on-hook to open the loop by opening the extension OPN by on-hook the extension subscriber.
Return to idle state.

In the case of restoration from the private branch exchange PBX, the extension subscriber's on-hook causes Lelugu release OPN, and the exchange CO detects the restoration and enters an idle state.

Figure 5 is an explanatory diagram of the sequence when a call is made from the private branch exchange PIIX to the exchange CO. . Exchange coFi thereby T-
Send dial tone DT as G, R+-J. In addition, in the case of the ground start method, the private branch exchange PBX detects activation of the exchange CO and sets the loop open CLS. It is sent to the exchange center CO due to intermittent loose dials.

When the exchange CO Hiro dial reception is complete, it sends a shilling back tone RBT, and the called subscriber responds with a response ANS.
-n, x4-a and transitions to a talking state.

The called subscriber's on-footer exchange co enters the idle state. In this recovery operation, T←E, R+-
The L private branch exchange PBX will be able to detect the recovery of the exchange 56co since neither the tip line nor the ring line K has a ground.The L private branch exchange PBX will open the loop OPN.

Table #11 shows the game signals for the ground start method and the loop start method using the above-mentioned symbols.

In tables j11 and 111, depending on the configuration of the exchange, there may be cases where there are no signals shown in numbers 1 to 4.

In the embodiment shown in No. 11111, polarity reversal
1 Relay JIL has been restored to operation, and private branch exchange @ PJ
IX will not be able to monitor polarity reversal. However, Hiro's problem is not that complicated. That is, (1) loop start method CO recovery 15 (for No. 1, exchange 14C
O was restored first, and at 9 o'clock, the extension line was subscribed to by listening to the busy tone ETt- from the CO exchange.

Ll) In response to the GO subscriber response signal, this signal is necessary for a system that has a billing function in the private branch exchange pxx and also performs KM calculation when the polarity of the response is reversed, and this necessity is extremely limited. This is only applicable to some private branch exchanges, and the mainstream method is to use out-of-band frequencies such as 50H1, 12KHz, 514KIh, etc. as billing notes.

In addition, if it is necessary to detect polarity reversal, use 9-ray RE
, it is possible to extract it as a signal data and identify it with the control device of the private branch exchange PIJX, as shown by the point 11wJ, whether or not it has operated.

FIG. 4 shows the relationship between the private branch exchange and the trunk according to the embodiment of the present invention, where FDET is the polarity detection circuit shown in FIG.
T and the ring line R are the central line L1. Regardless of the polarity of L2,
They are switched and connected to have a predetermined polarity. Also 11 DJI
T is a ringing detection circuit, LDIjT is a loop detection circuit, GDHT is a diode I) which connects the ground of the chip IIT and the ring line R.2. The ground detection circuit detects the signals via the DSt, and the IIVDI:T#i polarity inversion signal detection circuit transfers the detected signals to the control device of the private branch exchange (not shown).

In addition, the contact point of the relay controlled by the control device of the private branch exchange, etc.
), also indicates that it is connected to the ywB private branch exchange network.

When a call arrives, the incoming signal shown in the 1m1 table is detected by the ground detection circuit GDET and the ringing detection circuit EDIT, and the tiI point m@a6""'#68B +81 is activated to open the loop as a PjlX response signal. . During a call, the loop detection circuit LDIi:T monitors the loop current, and in the case of a system in which a polarity reversal signal is sent from the exchange, the polarity reversal signal detection circuit AVDH monitors the loop current.
'l' Kyoru is detected.

In addition, in the case of the ground start method, the contact a0 is operated to send out a ring wire ground start signal, and in the case of the loop start method, the contact O・1゜~-＠a2e＠
1 is operated and a loop closing activation signal is sent. In the case of the ground start method, the CO start-up is ensured by the line 1 chip line ground, so the ground detection enclosure GDIi
jT is detected, and the contact point -〇#0～-・
amp@1 operates and loop closure is performed. The dial signal is sent out when the contact is turned on and off, and in that case, the contact at is switched to the resistance side to prevent distortion of the dial pulse waveform due to the inductance of the transformer.

As mentioned above, it can be applied to both the ground start method and the loop start method, and the connection polarity of the stations Ll and Ll [must be taken into account! It has a short composition.

Figure 5 shows another embodiment of the present invention, in which the same reference numerals as in Figure 4 indicate the same parts, and the ground detection circuit GD11.
7 and ring wire ground start signal transmitter Rt, polarity detection group pniir relay EL contact f'Os de 11
It is designed so that it can be switched and connected.

Also, the loop detection circuit LDET is connected to the station @L1. Since there is no switching connection between L2 and the trunk chip IIT and ring 1ilR, the configuration is such that bidirectional loop currents can be detected.

When a call arrives, the ringing detection circuit EDIjT detects p ringing and sends out a response signal by closing the loop. At the time of transmission, in the case of the ground start method, a starting signal for the shilling line ground is sent through the contact @-, and CO starting confirmation of the tip line ground is monitored in the same way as in the case of FIG. Furthermore, since the polarity inversion signal line loop detection circuit LDIiT enables detection of bidirectional current, it is possible to detect a reversal of the current direction.

That’s all 1llS! As is clear, the present invention detects the connection polarity of the office using the polarity detection path PDIjr, and
The connection ms' of the office line drawn into K is switched and connected by the contact rit of the relay 11L so that the connection ms' of the office line drawn into K is constant, or the ground detection circuit GDIIT is used to detect the ground of the chip line T, and the ground is sent out by the contact G0. For the means and t station line, relay RLf) g point IJ! 0srj! t
This has the advantage that it is not necessary to consider the polarity of the central office line during inspection work during installation work. Further, it can be applied to either a ground start method or a loop start method.

Also, it is possible to use a diode bridge as a means of non-polarization, but when such a diode bridge is used, the disadvantage is that the level of the call signal and the game signal decreases due to the voltage sieving caused by the diode. This means that it cannot be applied to the ground start method. That is, the activation signal from the private branch exchange PEX side via the fern wire ground is blocked by the diode bridge and is not sent out. Also, l of the ringing detection circuit 11DET
If it is not provided at Hj, ringing cannot be detected, and furthermore, polarity inversion signals cannot be detected at all.

However, according to the present invention, all of the problems caused by the diode bridge can be solved, and the effects of the present invention are very large as well as improving the workability and maintainability of the central line.

[Brief explanation of the drawing]

Figure liI is a circuit diagram of the main part of the embodiment of the present invention, Figures 2 and 5 are explanatory diagrams of 7-points at the time of incoming and outgoing calls, and Figures 4 and 5 show the relationship with the trunk of the private branch exchange. FIG. 2 is a circuit diagram of a main part of an embodiment of the present invention shown in FIG. Ll, 12 mine line, T line tip line, 8 company ring line, 8
1~85Fi resistor s C1~C5ijs y capacitor, I
ILI-1 relay, 11. rJio+rj! t
is a relay contact, 91 to Q4 are transistors, FD
ET is a polarity detection circuit, RDIT is a ringing detection circuit, GDIT stock ground squishing circuit, LDI:T is a loop detection circuit, EVDJITfl polarity reversal reconnaissance detection ° (
b) Road. Patent applicant Fujitsu Ltd. Patent attorney Tamamushi five other members

Claims (1)

[Claims] A polarity detection circuit including a relay that detects and operates the connection polarity of the office line drawn from the exchange to the private branch exchange, and a switching connection or connection so as to keep the connection polarity of the office line drawn into the private branch exchange constant. The expanded ground detection means and the ground sending means are ll1J&! A station-to-inter7 ace enclosure comprising a contact point of the relay which is switched and connected in accordance with the connection polarity of the station.