CN2527044Y - Internal and external network isolator - Google Patents
Internal and external network isolator Download PDFInfo
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- CN2527044Y CN2527044Y CN 02228019 CN02228019U CN2527044Y CN 2527044 Y CN2527044 Y CN 2527044Y CN 02228019 CN02228019 CN 02228019 CN 02228019 U CN02228019 U CN 02228019U CN 2527044 Y CN2527044 Y CN 2527044Y
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Abstract
An isolator of the internal and the external net consists of a rectifier and filter circuit, an on-off circuit, a light coupler, an inverse circuit, a switch pipe and a relay; wherein the telephone line is connected with the input end of the rectifier and filter circuit through an adjustable resistance R0 bridge-connected on the isolator; the output end of the rectifier and filter circuit is connected with the input end of the on-off circuit; the output end of the on-off circuit is connected with the input positive electrode 1 of the light coupler IC1; the output negative electrode 2 of the light coupler is grounded; and an output end 4 of the light coupler is grounded; an output end 6 thereof is connected with the output end 4 through resistance R8; an output end 5 is divided into two paths, a path thereof is connected with the 5V power in the computer through a resistance R7, and the other path thereof is connected with the input end of the inverse circuit; the output end of the inverse circuit is connected with the base electrode of the switch pipe T5; the emitting electrode of the switch pipe T5 is grounded; the collecting electrode is connected with the 5V power in the computer through the relay J1, and relay J1 controls the switch arranged in the net wire.
Description
Technical field
The utility model relates to Network Security Device, and is specifically a kind of when dialling up on the telephone, and disconnects the inside and outside network isolator that this machine is connected with local area network (LAN).
Background technology
In today of rapid development of information technology, it is particularly important that network security seems.In the past in order to guarantee the safety of local area network (LAN), people come the people for ensuring information security by plug netting twine constantly, and not only " forgetting to pull out " phenomenon also often appears in complex operation, and safe handling has brought serious hidden danger to LAN.
Summary of the invention
When the purpose of this utility model is to provide a kind of user to dial up on the telephone by Modem,, guarantee the inside and outside network isolator of the safety of other computer in the local area network with the binding physics partition of main frame and local area network.
For achieving the above object, the utility model adopts following technical scheme: a kind of inside and outside network isolator, its special character is that it is by current rectifying and wave filtering circuit, switching circuit, optical coupler, negater circuit, switching tube and relay are formed, wherein, telephone wire links to each other with the input of current rectifying and wave filtering circuit by cross-over connection adjustable resistance R0 thereon, the output of current rectifying and wave filtering circuit links to each other with the input of switching circuit, the output of switching circuit links to each other with anodal 1 pin of the input of optical coupler IC1, the input negative pole 2 pin ground connection of optical coupler, the output 4 pin ground connection of optical coupler, 6 pin are connected together by resistance R 8 and 4 pin, 5 pin are divided into two-way, the resistance R 7 of leading up to links to each other with 5V power supply in the computer, another road links to each other with the input of negater circuit, the output of negater circuit links to each other with the base stage of switch transistor T 5, the grounded emitter of switch transistor T 5, and collector electrode links to each other with 5V power supply in the computer by relay J 1, be parallel with a diode D2 on relay J 1 side, the positive pole of this diode D2 links to each other with the collector electrode of switch transistor T 5, and negative pole links to each other with the 5V power supply, and relay J 1 control is installed in the switch in the netting twine.
In such scheme, described switching circuit is made up of triode T1, T3, T4 and biasing resistance R1, R2, R3, R4, R5 and capacitor C 3, wherein, the emitter of triode T1, T3 links to each other with the negative pole of output end of current rectifying and wave filtering circuit, the base stage of triode T1 links to each other with a point between biasing resistance R1, the R2, collector electrode is divided into two-way, the resistance R 3 of leading up to links to each other with the output head anode of current rectifying and wave filtering circuit, another road links to each other with the base stage of triode T3 and an end of resistance R 5 respectively, and the negative pole of output end of the other end current rectifying and wave filtering circuit of resistance R 5 links to each other; The collector electrode of triode T3 links to each other with resistance R 4 one ends with the base stage of triode T4 respectively, and resistance R 4 other ends link to each other with the output head anode of current rectifying and wave filtering circuit; The emitter of triode T4 links to each other with the output head anode of current rectifying and wave filtering circuit, and collector electrode links to each other with anodal 1 pin of the input of optical coupler IC1 by resistance R 6.
In such scheme, described negater circuit is made up of three groups of reversers that are serially connected and resistance R 10, and resistance R 10 1 terminates at the output of the last grade reverser.
In dialing with during jingle bell (non-talking state), the voltage of 50-60V is arranged on the telephone wire, when answering the call, voltage drops to and has only 10-15V, just returns to 50-60V when on-hook.
The utility model is to conciliate in dialing according to the voltage on the telephone line acute variation (50-60V is to 10-15V) development takes place simultaneously.This isolator is installed to when working on the PCI slot of computer, the make progress variation of voltage of the phone of supervision on Modem, in dial-up Internet, the voltage step-down (10-15V) that phone makes progress, satisfied the condition of isolator partition local area network (LAN), isolator disconnects the link of local area network, reaches the safety of online other computer of protection local area; When break link, the voltage on the telephone wire recovers (50-60V), and the detected voltage of isolator recovers to connect the local area network.
The utility model adopts pure hardware manufacturing, has motherboard that 5V is provided power supply, starts working when main frame begins, stop during shutdown, connect from the bottom (hardware) Control Network link, network data is all transmitted by isolator, do not take the processing time of CPU, thereby reduced the processing expenditure of CPU.
The utility model provides the Media Interface Connector of 2 RJ45, is used for being connected with twisted-pair feeder.2 RJ11 interfaces are provided, are used for being connected with Modem with telephone wire.Support the computer of 10/100Mbps to connect with hub (switch); Connecting between computer and the computer; Hub (switch) connects with hub (switch).
In sum, the utility model can play when dialling up on the telephone really, disconnects the link effect of this machine and LAN.And do not influence the LAN channel performance.
Description of drawings
Fig. 1 is a circuit diagram of the present utility model.
Fig. 2 is an external wiring diagram of the present utility model.
Embodiment
Fig. 1 is a specific embodiment of the utility model.Adjustable resistance R0 is connected across on two telephone wire LINE of input in Fig. 1, and current rectifying and wave filtering circuit I is made up of rectifier bridge B1, capacitor C 1, C2.Wherein, capacitor C 2 is connected across between positive and negative two outputs of rectifier bridge, capacitor C 1 one end ground connection, and the other end links to each other with the cathode output end of rectifier bridge.
Switching circuit II is made up of triode T1, T3, T4 and biasing resistance R1, R2, R3, R4, R5 and capacitor C 3.The relative V of T1, T3
AMake a response, control T4 is logical.
Optical coupler IC1 adopts the 4N33 model, and its input has 1,2 two pin, and output has 4,5,6 three pin.The output of switching circuit II links to each other with anodal 1 pin of the input of optical coupler IC1, the input negative pole 2 pin ground connection of optical coupler, the output 4 pin ground connection of optical coupler, 6 pin are connected together by resistance R 8 and 4 pin, 5 pin are divided into two-way, the resistance R 7 of leading up to links to each other with 5V power supply in the computer, and another road links to each other with the input of negater circuit III.
Negater circuit III comprises three groups of reversers that are serially connected and resistance R 10.Resistance R 10 1 terminates at the output of the last grade reverser.Be serially connected with resistance R 9 between first order reverser among the negater circuit III and the second level reverser, be parallel with a diode D1 on resistance R 9 sides, the positive pole of this diode D1 is connected on the input of second level reverser and the b point between the resistance R 9, negative pole is connected between the output and resistance R 9 of first order reverser, and above-mentioned b point is also by capacitor C 4 ground connection.Above-mentioned resistance R 9, diode D1 and capacitor C 4 can make relay J 1 inhale slowly and put soon.Above-mentioned the last grade reverser by the time reverser in parallel constitute.
The output of negater circuit (being the other end of resistance R 10) links to each other with the base stage of switch transistor T 5, the grounded emitter of switch transistor T 5, collector electrode links to each other with 5V power supply in the computer by relay J 1, be parallel with a diode D2 on relay J 1 side, the positive pole of this diode D2 links to each other with the collector electrode of switch transistor T 5, negative pole links to each other with the 5V power supply, and relay J 1 control is installed in the break-make of the normally closed switch K in the netting twine.
The operation principle of this circuit is:
Normality: V
A≈ 48V (48V, in fact greater than 50V) in theory → V
Be1＞0.6V (T1 conducting) → 0.6V 〉=V
Be3Top ≈ 0V → T5 disconnection → relay J 1 not adhesive of 〉=0 (T3 disconnection) → T4 disconnection → optocoupler disconnection → optocoupler 5 pin ≈ 5V → R10 → normally closed switch K connects, and netting twine is logical.
Conversation: V
A≈ 10-2.5V (when many extension sets use simultaneously) → V
Be1＜0.3V (T1 disconnection) → V
Be3Top＞4V of 〉=0.6V (T3 conducting) → T4 conducting → optocoupler conducting → optocoupler 5 pin≤1.6V → R10 → T5 conducting → relay J 1 adhesive → normally closed switch K disconnects, and netting twine is obstructed.
The utility model is installed in the computer PCI bus slot.Its mode of connection is with reference to Fig. 2.
Claims (4)
1, a kind of inside and outside network isolator, it is characterized in that it is by current rectifying and wave filtering circuit, switching circuit, optical coupler, negater circuit, switching tube and relay are formed, wherein, telephone wire links to each other with the input of current rectifying and wave filtering circuit by cross-over connection adjustable resistance R0 thereon, the output of current rectifying and wave filtering circuit links to each other with the input of switching circuit, the output of switching circuit links to each other with anodal 1 pin of the input of optical coupler IC1, the input negative pole 2 pin ground connection of optical coupler, the output 4 pin ground connection of optical coupler, 6 pin are connected together by resistance R 8 and 4 pin, 5 pin are divided into two-way, the resistance R 7 of leading up to links to each other with 5V power supply in the computer, another road links to each other with the input of negater circuit, the output of negater circuit links to each other with the base stage of switch transistor T 5, the grounded emitter of switch transistor T 5, collector electrode links to each other with 5V power supply in the computer by relay J 1, is parallel with a diode D2 on relay J 1 side, and the positive pole of this diode D2 links to each other with the collector electrode of switch transistor T 5, negative pole links to each other with the 5V power supply, and relay J 1 control is installed in the switch in the netting twine.
2, according to the described inside and outside network isolator of claim 1, it is characterized in that described switching circuit is by triode T1, T3, T4 and biasing resistance R1, R2, R3, R4, R5 and capacitor C 3 are formed, wherein, triode T1, the emitter of T3 links to each other with the negative pole of output end of current rectifying and wave filtering circuit, the base stage of triode T1 and biasing resistance R1, A point between the R2 links to each other, collector electrode is divided into two-way, the resistance R 3 of leading up to links to each other with the output head anode of current rectifying and wave filtering circuit, another road links to each other with the base stage of triode T3 and an end of resistance R 5 respectively, and the negative pole of output end of the other end current rectifying and wave filtering circuit of resistance R 5 links to each other; The collector electrode of triode T3 links to each other with resistance R 4 one ends with the base stage of triode T4 respectively, and resistance R 4 other ends link to each other with the output head anode of current rectifying and wave filtering circuit; The emitter of triode T4 links to each other with the output head anode of current rectifying and wave filtering circuit, and collector electrode links to each other with anodal 1 pin of the input of optical coupler IC1 by resistance R 6.
3, according to the described inside and outside network isolator of claim 1, it is characterized in that described negater circuit is made up of three groups of reversers that are serially connected and resistance R 10, resistance R 10 1 terminates at the output of the last grade reverser.
4, according to the described inside and outside network isolator of claim 3, it is characterized in that being serially connected with resistance R 9 between first order reverser in described negater circuit and the second level reverser, be parallel with a diode D1 on resistance R 9 sides, the positive pole of this diode D1 is connected on the input of second level reverser and the b point between the resistance R 9, negative pole is connected between the output and resistance R 9 of first order reverser, and above-mentioned b point is also by capacitor C 4 ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02228019 CN2527044Y (en) | 2002-01-04 | 2002-01-04 | Internal and external network isolator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02228019 CN2527044Y (en) | 2002-01-04 | 2002-01-04 | Internal and external network isolator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2527044Y true CN2527044Y (en) | 2002-12-18 |
Family
ID=33704687
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02228019 Expired - Fee Related CN2527044Y (en) | 2002-01-04 | 2002-01-04 | Internal and external network isolator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2527044Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104618363A (en) * | 2015-01-21 | 2015-05-13 | 太仓唐策工业科技有限公司 | Safe connection mechanism for network |
-
2002
- 2002-01-04 CN CN 02228019 patent/CN2527044Y/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104618363A (en) * | 2015-01-21 | 2015-05-13 | 太仓唐策工业科技有限公司 | Safe connection mechanism for network |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |