CN1210930C - Automatic offhook device for telephone communication - Google Patents
Automatic offhook device for telephone communication Download PDFInfo
- Publication number
- CN1210930C CN1210930C CN 02117184 CN02117184A CN1210930C CN 1210930 C CN1210930 C CN 1210930C CN 02117184 CN02117184 CN 02117184 CN 02117184 A CN02117184 A CN 02117184A CN 1210930 C CN1210930 C CN 1210930C
- Authority
- CN
- China
- Prior art keywords
- circuit
- composite pipe
- resistance
- telephone
- directional
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Telephone Function (AREA)
Abstract
The present invention relates to an automatic off-hook device for telephone communication, which belongs to the field of remote control of a telephone and solves the problem that the existing off-hook and on-hook control device for telephone communication has the disadvantages of high cost, large volume and bad safety performance. The present invention comprises a directional circuit which is composed of diodes D1, D2, D3, D4, a composite pipe circuit which is composed of a resistor R6 and transistors T2, T1, a voltage-sensitive resistor ZNR, an equivalent resistor which is composed of resistors R4, R5 and a DC resistor of an audio transformer, and a microprocessor. The present invention is characterized in that a telephone wire CJ2 is connected with the directional circuit, and the voltage-sensitive resistor ZNR is switched in the directional circuit in the connection in parallel mode. The negative end of the directional circuit is connected with the ground, and the positive end of the directional circuit is connected with the emitting electrode of the transistor T1 in the composite pipe circuit. Collectors of the transistors T1, T2 in the composite pipe circuit are connected with the equivalent resistor, and the microprocessor is connected with the base electrode of the transistor T2 in the composite pipe circuit through a photocoupler U7-2. The present invention is mainly applied to a telephone device for home network communication.
Description
Technical field
The present invention relates to a kind of automatic offhook device that is used for telephonic communication, belong to telephone remote control field.
Background technology
The automatic off-hook technology of existing telephonic communication normally utilizes the double-tone frequency power transformer to regulate the resistance value that smart phone inserts telephone network, so that make its impedance and loop current meet the requirement of national standard telephone network.And double-tone frequency power transformer volume is bigger, and does not domesticly produce in batches, needs customization or from ordering abroad.Therefore, the dislodging machine control device of existing smart phone exists cost height, volume big, and perhaps poor safety performance may be damaged the equipment of telephone office, the problem that telephone network is had a negative impact.
Summary of the invention
At above-mentioned the problems of the prior art, the invention provides that a kind of cost is low, security performance good, the automatic offhook device that is used for telephonic communication that telephone network is not exerted an influence.
Technical scheme of the present invention, realize as follows:
The composite pipe circuit that a kind of automatic offhook device that is used for telephonic communication comprises the directional circuit be made up of diode D1-D4, be made up of resistance R 6, triode T2 and T1, piezo-resistance ZNR, the equivalent resistance of forming by the D.C. resistance of resistance R 4 and R5, audio frequency transformer, microprocessor.Its design feature is, telephone wire CJ2 connects directional circuit, the piezo-resistance ZNR directional circuit that inserts in parallel, the directional circuit negativing ending grounding, anode connects the emitter of triode T1 in the composite pipe circuit, the collector electrode of triode T1 and T2 is connected with equivalent resistance in the composite pipe circuit, and microprocessor connects the base stage of triode T2 in the composite pipe circuit by optocoupler U7-2.
The present invention has protected telephone communication device owing to used the make a return journey high voltage interference of telephone wire of piezo-resistance.Also used equivalent resistance to come regulating system to insert the resistance value of telephone network in this device, guaranteed that the direct current in the telephone wire is about 20MA when triode T1 conducting.Avoided the influence of device, reduced the cost of phone dislodging machine control device Be Controlled electrical equipment and telephone network.Audio frequency transformer has been realized the mutual coupling of signals such as DTMF, voice, process simultaneously, and realizes the electrical isolation of telephone wire and microprocessor.
Description of drawings
Accompanying drawing is a circuit connection diagram of the present invention.
Embodiment
Referring to accompanying drawing, the composite pipe circuit 2 that a kind of automatic offhook device that is used for telephonic communication comprises the directional circuit 1 be made up of diode D1-D4, be made up of resistance R 6, triode T2 and T1, piezo-resistance ZNR, by the equivalent resistance 3 that the D.C. resistance of resistance R 4 and R5, audio frequency transformer B1 is formed, model is a 89C52 microprocessor 4.Its design feature is, telephone wire CJ2 connects directional circuit 1, the piezo-resistance ZNR directional circuit 1 that inserts in parallel, directional circuit 1 negativing ending grounding, anode connects the emitter of triode T1 in the composite pipe circuit 2, the collector electrode of triode T1 and T2 is connected with equivalent resistance 3 in the composite pipe circuit 2, and microprocessor 4 is the base stage that the optocoupler U7-2 of TLP521 connects triode T2 in the composite pipe circuit 2 by model.When the pin of microprocessor 4 was high level, 6, the 5 pin conductings of optocoupler U7-2 made the T1 conducting of composite pipe circuit 2.No matter the polarity of telephone wire how, directional circuit 1 guarantees that the emitter of T1 is positive voltage.Piezo-resistance ZNR be for the high-tension interference of removing telephone wire as thunderbolt etc., the protection phone module is unlikely to damage.When the T1 conducting, equivalent resistance 3 guarantees that the direct current in the telephone wire is: about 20MA, realize normal handoff functionality.Audio frequency transformer B1 realizes the mutual coupling of signals such as DTMF, voice, process simultaneously, and realizes the electrical isolation of telephone wire and microprocessor.
Claims (2)
1. automatic offhook device that is used for telephonic communication, comprise the directional circuit of forming by diode D1-D4 (1), by resistance R 6, the composite pipe circuit (2) that triode T2 and T1 form, piezo-resistance ZNR, by resistance R 4 and R5, the equivalent resistance (3) that the D.C. resistance of audio frequency transformer B1 is formed, microprocessor (4), it is characterized in that, telephone wire CJ2 connects directional circuit (1), the piezo-resistance ZNR directional circuit (1) that inserts in parallel, directional circuit (1) negativing ending grounding, anode connects the emitter of triode T1 in the composite pipe circuit (2), the collector electrode of triode T1 and T2 is connected with equivalent resistance (3) in the composite pipe circuit (2), and microprocessor (4) connects the base stage of triode T2 in the composite pipe circuit (2) by optocoupler U7-2.
2. device as claimed in claim 1 is characterized in that, described microprocessor (4) model is 89C52, and the model of described optocoupler U7-2 is TLP521.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02117184 CN1210930C (en) | 2002-04-27 | 2002-04-27 | Automatic offhook device for telephone communication |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02117184 CN1210930C (en) | 2002-04-27 | 2002-04-27 | Automatic offhook device for telephone communication |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1453977A CN1453977A (en) | 2003-11-05 |
| CN1210930C true CN1210930C (en) | 2005-07-13 |
Family
ID=29257206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02117184 Expired - Fee Related CN1210930C (en) | 2002-04-27 | 2002-04-27 | Automatic offhook device for telephone communication |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1210930C (en) |
-
2002
- 2002-04-27 CN CN 02117184 patent/CN1210930C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1453977A (en) | 2003-11-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1210930C (en) | Automatic offhook device for telephone communication | |
| CN2549665Y (en) | Automatic take-off device for telephone communication | |
| CN207039807U (en) | Digital SPC exchange | |
| CN103414070B (en) | A kind of audio signal reception and switching device | |
| CN216290291U (en) | Quick charging circuit module based on gallium nitride | |
| CN201323608Y (en) | Two-wire system nursing communication device with large installed capacity | |
| CN2549670Y (en) | Pick-off controller of intelligent telephone | |
| CN2442310Y (en) | Data communication interface device of passive telephone line | |
| CN2240214Y (en) | Theft-proof device for telephone | |
| CN202197318U (en) | Terminal | |
| CN2450839Y (en) | Cordless telephone with phone interface circuit | |
| CN219611784U (en) | Amplifier with half-duplex automatic receiving and transmitting function for interphone | |
| CN213635364U (en) | Take audio decoding transmission's fill data line soon | |
| CN2211676Y (en) | Circuit protector against illegal trunk multiple | |
| CN2263425Y (en) | Program-control switchboard subscriber interface feeding device | |
| CN203984514U (en) | A kind of transistor type message handler | |
| CN208479238U (en) | A kind of vertical mobile phone charging pile | |
| CN202841304U (en) | Wide-range automatically-controlled sensing adapter | |
| CN2426654Y (en) | Digital mobile set top box for TV set | |
| CN202899991U (en) | Proximitor convenient and easy to achieve | |
| CN2565222Y (en) | User interface circuit device | |
| CN2188827Y (en) | Portable magnet, common battery, automatic telephone set | |
| CN2163491Y (en) | Telephone anti-theft alarm | |
| CN2300220Y (en) | Telephone exchange using AC power cord transmission signal | |
| CN2227892Y (en) | Automatic anwsering function expander for modem |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee |
Owner name: TONGFANG CO., LTD. Free format text: FORMER NAME OR ADDRESS: TSINGHUA TONGFANG CO., LTD. |
|
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20050713 Termination date: 20170427 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |