JPS58134569A - Power supply system for network controller - Google Patents

Abstract

PURPOSE:To apply a network controller to a system in which a commercial power supply is not obtained easily, by applying the power supply required for the network controller from an exchange side. CONSTITUTION:The power supply transmitted from an exchange via a circuit TL is rectified at a rectifier circuit 31 and applied to constant current circuits 32, 34. A make signal and a minimum pause signal of a DP (dial pulse) are formed with the sum of a current I1 flowing to a constant voltage circuit 33 through the circuit 32 and a current I2 flowing a switch 35 through the circuit 34 and a brake signal of the DP is formed with the current I1. The transmission of the DP is done by turning on/off the switch 35 with a dial pulse forming circuit receiving the supply of power at the circuit 33. Thus, the network controller of a data terminal is controlled only with the power supply from the exchange.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a network control system connected to a subscriber telephone line (hereinafter simply referred to as ins or telephone line L&J line), which controls the connection of R*II data terminal equipment to the line. ! J
0 is a conceptual diagram showing a data transmission system using such a network control device.
1' is a telephone exchange or a switching network, 2 is a network control device, and 3 is a data terminal device. The terminal device 3 is connected to the telephone switching network 1 under the control of the network control device 2. In such a system, the electric power (Jli) of the telephone exchange 111 is used only for loop closure, sending selection signals, or creating loop-pattern signals, and is not used by the network that controls these networks. Conventionally, the power source 11 of the control device 2 was supplied from the commercial electric power jl[P8. For example, if the network control device 2
When requesting communication with 1), it is necessary to send out a selection signal, that is, a dial pulse (hereinafter simply referred to as DP). This sending of 1)P was performed as follows.

FIG. 2 is a circuit diagram showing a conventional dial pulse sending circuit.

In the figure, 11 is an electric MTM line that inputs commercial power and generates the power necessary for various circuits, 12 is a diamond pulse generation circuit that generates make signals, break signals, and minimum pauses, and L is a dial pulse sending relay. is the contact of relay L that sends out the dial pulse, and 13 is the relay contact! 14 is a resistor that limits the current in the same line. 15 is a spark killer.

The relay L is operated by the dial pulse generating circuit 12, and dial pulses are transmitted by turning the contact 4 on and off.

Therefore, since it requires a commercial power source as its operating power source,: 1) Communication becomes impossible during a power outage of the commercial power source.

2) In systems where the terminal device does not use a power source and operates on batteries or the like, it is necessary to install a commercial power source especially for the network control device.

The present invention has been made in view of the above points, and has the following objects: 1. By providing a network control device that does not require commercial power, it is possible to apply it to systems where commercial power is not easily available. shall be.

Simply put, the feature of the present invention is that the power necessary for the network control device is supplied from the exchange side. To elaborate, there is a rectifier path that rectifies the voltage supplied from the exchange side, and a rectifier connected to the load of the rectifier circuit and whose output current level is operated by the functional elements of the AC. or at least one constant current circuit that maintains the current level at a predetermined current level that does not lead to recovery, and by driving the network control device at the predetermined current level, the network control device performs a predetermined operation. This allows the network control device to function as a switch without affecting the switch in any way.

When the deviation of the current is determined as a rare value, the output currents of the constant current paths are combined and a selection signal of a predetermined level (1 level) is sent out.

Hereinafter, embodiments of the present invention will be described with reference to i**.

The 3rd WJ is a block diagram showing an embodiment of the present invention, particularly an example of a DP sending circuit for sending out DP in response to the supply of local power, and 45th! J is a waveform diagram for explaining the operation.

In Fig. 3, 131 is a rectifier circuit for rectifying the power sent through the circuit 1iITL (the voltage supplied from the exchange side is DC, but one polarity may be reversed, so ), 32 is a constant current circuit that generates the current necessary for each circuit, 33 is a constant voltage circuit that generates the voltage necessary for various circuits, 1
2 is a dial pulse creation circuit similar to 12 in Figure 2 for creating make signals, break signals, and minimum pause;
34 is a constant current circuit for creating a dial pulse; 35 is a switch that receives a signal from the dial pulse creating circuit 12 and creates a dial pulse by the constant current circuit 34.

Note that the dial pulse generation path used here operates at a predetermined current level (It), and can be easily constructed using a known electronic circuit. Although the switch 35 is illustrated as an NPN transistor, it goes without saying that it can be replaced with a known switch circuit. Ik - current 11)
The constant current circuits 32 and 34 are designed so that the holding current is less than the holding current of the Dr receiving/receiving circuit relay on the exchange side, and 11 + 12 is more than the moving current of the relay of the DPP communication circuit on the exchange side.

Therefore, as shown in No. 411, the make signal and the two maze signals of The DP break signal is created by the above-mentioned current 11.

The DP can be sent out by turning on and off the switch 35 using a dial pulse generation circuit that receives power from the constant voltage electric circuit 33. By doing this, commercial power is not required. Dial pulses can be sent simply by receiving power from the exchange.

In this case, although a current is required at the time of a break, this current level is kept below the holding current of the relay 4 in the exchange@11DP reception path, so this does not interfere with the operation of the exchange.

The reason why the currents Il and 2 are constant currents by the four constant current paths 32 and 34 is to prevent the currents 11+I2 from changing due to differences in the line resistance of the telephone line depending on the installation location of the network control device. Therefore, when the line resistance is not an interlayer, the constant current -1134 can be replaced with an appropriate impedance element, for example.

Incidentally, the rectifying circuit or the constant voltage circuit can be constructed by a conventionally known circuit.

The above describes the case where the present invention is applied to the function of a network control device sending out dial pulses. 1□ can also be effectively applied to other functions of the network control device, ie, functions such as call collision monitoring during call origination and guaranteed network recovery time monitoring.

The call collision monitoring operation of the network control device refers to a series of operations for preventing collision between a call originating from the network control device and an incoming call from the exchange. In other words, by operating the call collision monitoring circuit at a current lower than the current of the call monitoring relay of the exchange value, the exchange side considers the loop open and the network control device performs a series of operations to prevent call collisions. I can do it.

The guaranteed network recovery time is the time it takes for the exchange to complete a series of operations for network recovery after the network control equipment opens the loop, and the network control equipment will call again until this operation is completed. I can't do that.

By operating the network control device's guaranteed network recovery time monitoring circuit at a current lower than the holding current of the call monitoring relay on the exchange side, the exchange side determines that the loop is open and performs the following steps to restore the line.
- Perform the action. At the same time, the network controller can perform network restoration line time monitoring operations.

An example of application of the invention described above is shown in FIG.
The sensitivity of the call monitoring relay of ll1 sardine is set to below the radio wave, below the meeting or holding current, etc., and the DP creation circuit 1i' is replaced with a call collision monitoring circuit or a line recovery guaranteed time monitoring circuit, etc., and the constant current circuit 34. This can be easily realized by replacing the switch 35 with a circuit necessary for each operation.As mentioned above, according to the present invention, the single network control device can be operated only by the local power supply. Since an external power source is not required, the cost can be reduced accordingly, and it can also be used in places where an external power source is not available, so there are no restrictions on where it can be used.

The present invention can be widely applied not only to the network control device described above, but also as a power supply system for devices in general that use a switched network.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing a data transmission system using a network control device, Fig. 2 is a circuit diagram showing a dial pulse sending circuit used in a conventional network control device, and Fig. 3 is an embodiment of the present invention. FIG. 4 is a waveform diagram for explaining the operation of $311. Code explanation l...Switchboard or telephone exchange network, 2...
・Network control device, 3...Data terminal device, ll・
...11 circuit, 12.12'...Dial pulse creation circuit, L...Dial pulse sending relay, I...Sending relay L contact, 13.・・・
...Spark extinguishing circuit, 14...Current limiting resistor,
15... Spark killer, 31... Rectifier circuit, 32.34... Constant current path, 33...
... Constant voltage power supply circuit, 35 ... Switch agent Patent attorney Akio Namiki Daibato Patent attorney Kiyoshi Matsuzaki

Claims (1)

[Claims] This is a network control device mm supply system in which power is supplied from the exchange side to the network control device that is connected between a telephone line and a data terminal device and controls the connection of the terminal device to I&III. - A rectifier path for rectifying the power supply, and a predetermined current level that is connected to the load of the rectifier circuit and sets its output current level to a predetermined current level within a range that does not cause a relay, etc., which is a functional element of the exchange, to operate or recover. and at least one constant current path maintained at a constant current level, and by driving the network control device with the predetermined current level, the predetermined functional operation to be performed by the device has no effect on the exchange price. In addition, the signal from the network control device to the switch can be sent by appropriately combining the output currents of the specified current circuits to create a signal and sending the signal. Features a power supply system for network control equipment.