Η Α7 Β7 經濟部中央棣準局貝工消费合作社印裂 五、發明説明（） 發明背景： 本發明係一種防止付費電話被盜撥之装置及其方法， 尤指一種應用在四線式電話線糸統上，藉在付費電話之電 路中装設一電壓偵测電路及接地線切斷電路，俾當付費電 話被其它電話不正常並接時*則不論該付費電話是否在使 用吠態，均可由中央處理單元主動偵測出是否有盗接電話 *並當偵測該付費電話被其它電路並接時，則將付費電話 之電路開路，K防止被盜打免費電話。 先前技藝： 按*我國雖採二線式之電話線作為電信局交換機與付 費電話連線之媒介，但在其它國家如英國則採四線電話線 為電信局交換機與付費電話之連媒，請參閱第一圖所示* 該四線式付費電話9 0傜藉插入I C卡9 0 0之方式打電 話，惟，若有人將一般電話機7 〇電話線之二通諾線7 0 1、702分別與該四線式電話線87之接地線E及該I C卡9 00之接地點90 1相連接，則該I C卡900插 入該付費電話9 0後，即可在該一般電話機7 0上撥打免 費電話。 請參閱第二圖所示，若將一般電話機7 0之二通話線 70 1、7 02分別與該四線式電話線87之接地線E及 該付費電話9 0話茼90 2上之接地線GN D相連接時， 則亦可在此一般電話機7 0上打免費電話。 請參間第三圖所示，習知付費電話機90之電路ί系由 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度逋用中固國家橾準{ CNS ) Α4規格（210Χ297公釐> 經濟部中央揉準局具工消费合作社印製 424374 A7 B7五、發明説明（） 一響妗控制電路（RINGER CIRCUIT)、一 電磁耦合/高壓保護電路9 1、一整流電路9 2、~電源 電路93、一控制電路94、一開/關電路9 5及其它之 電話電路元件所組合而成。 該付費電話機9 0除藉由該響鈐控制電路接收從電信 局交換機經該電铃線S所傳來之電鈐訊號；該電磁耦合/ 高壓保護電路91之三輸入端係分別與電話線之二通諾溴 A _、B及接地線E相連接，該電磁耦合/高壓保護電路9 1之作用偽將該等電話線路A、B、E傳來之訊號作電磁 耦合及高壓輸入保護之處理，經處理後，再將訊號傳至該 整流電路92之二訊號輸入端；該整流電路9 2之接地端 係與付費電話之接地線G N D相連接，該整流電路9 2之 訊號輸出端則分別與該電源電路9 3、該控制電路9 4、 該開/闞電路95及其它之電路元件相連接。. 該開/闞電路9 5之輸入端係與該整流電路9 2之輸 出端相連接；該控制電路94設有一話茼開關94 1及一 電阻9 4 2，該話茼開關9 4 1係控制付費電話機s 0是 否在通諾狀態，該話筒開關94 1之輸入端並與一中央處 理簞元之一控制訊號接齡I相連接，俾該付費電話苏可藉該 中央處理軍元控制該付費電話9 〇通話與否° 再請參閱第一圖所示，當四線式付費電話機90並接 有一般電話機70時，則該一般電話機70即可藉該付費 電話機9 0之通話線路，而在該一般電話機7 〇上盜打免 費電話，故，此種習知付費電話90之電路裝置’顯然相 ^ In n^i 1 {請先聞讀背面之注意事項再填寫本頁) 本紙張尺度適用中國圉家標率（CNS > A4規格（210X W7公釐） 經濟部中央橾準局貝工消费合作社印装 4 2五、發明説明（） 當不理想。 發明網要： 本發明是一種防止付費電話被盗撥之装置及其方法， 利用在付費電話機之電路中加設一電壓偵測電路及一接地 線切斷電路，俾該付費電話被盜接後，即可將通話回路開 路而無法再撥打電話；本發明之原理係利用該付費電話之 中央處理單元判斷該電壓偵測電路之電壓值是否不正常下 降，若該中央處理單元偵測該電壓偵測電路之電壓值發生 不正常下降時，即可判斷該付費電話已被盗接，則該中央 處理軍元即透過其控制接腳發出一訊號令該接地線切蹑電 路開路，以避免該付費電話被人盗打免費電話。 有鑑於習知付費電話之通訊技術可被一般人以其它電 話並接盗打免費電話，發明人乃對肽缺失及依據多年來從 事製造產品之相關涇驗，悉心觀察且OT究之•而終於開發 設計出本發明 發明目的： 本發阴之目的，偽提洪一種防止付費電話破盗撥之装 置及其方法1利闬在付費電話之電路上加設一電壓偵測電 路及一接地線切斷電路；該電壓偵测電路係供付費踅話中 之中央處理器檢測該付費電話是否被不正常盗接；若該中 央處理翬元經湞測該付費電話被盜接時，則該中央處理單 (請先閣讀背面之注意事項再填寫本頁) ^^^1 ϋι> t- ί-· - —I J -- - - 1 - -訂--JI. 本紙張尺度適用中國國家標準（CNS > A4规格（210X297公嫠） 經濟部中央標準局舅工消費合作社印裝 B7五、發明説明（） 元即發出一訊號令該接地線切斷電路之繼電器斷電，此時 ，該盜接之電話卽無法藉付費電S之通話線路盜打免費電 話。 為使能對本發明之目的、形狀、構造装置持徵及其功 效，做更進一步之認_與瞭解，茲舉實施例配合圖式，詳 细說明如下： 圖式之簡m說明： 第一圖除電信局交換機與付費電話之連接線路之一可 被打免費公共電話之實施圖。 第二圖係電信局交換機與付費電話之連接線路之另一 可被打免費公共電諾之實施s s 第三圖傜習知付費公共電話與電話線路之局部詳细電 路麗。 第四圔係本發明葚施例之電路方瑰圖。 第玉圖慑本發明實施例之詳细電路圖。 第六圖傜本發明之動作流程圖。 主要元件圖號說明： 電磁耦合/高壓保護電路1 1 整流電路1 2 開/關電路1 3 控制電路1 4 電源電路1 5 電壓偵測電路2 0 接地線切斷電路3 0 本發明係一種「防止付費電話被盗撥之装置及其方法 (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） 經濟部中央標準局貝工消費合作杜印装 mi a ' A7 __B7_五、發明説明（） J ，請參閱第四圔所示，係在習知之一響鈐控制電路（R INGER CIRCUIT)、一電磁耦合/高壓保護 電路1 1、一整流電路12、一開/關電路13、一控制 電路1 4、一電源電路1 5 .、一中央處理單元及其它電路 元伴所組成之四線式付費電話之電路中，加設一電壓偵測 電路2 0及一接地線切斷電路3 0。 本發明偽藉該中央處理單元主動偵測該電壓偵測電路 2 0之電壓值是否下降，以判斷該付費電話之電路是否並 接有不正常之其它電話，若中央處理單元判斷該付費電話 並接有其它電話時，則該中央處理簞元即發出一控制訊號 切胺串接在該整流電路12接地端與付費電話接地線GN D間之該接地線切斷電路3 0，藉此防止四線式付費電話 遒人以並接之電話盜打免費電話。 該電S偵測電路2 0係接設在該整流電路1' 2之輸岀 端與付費電話之接地線G N D之間，係由分壓電阻2 1 0 、2 1 1及一電容2 2所組成；該分壓電阻2 1 0之輸入 端1與該整流電路1 2之輸出端相連接，該分壓電阻2 1 ◦之輸出端則分別與該分壓電阻2 1 1 、該電容2 2之輸 入端及該中央處理里元之類比/數位轉換器相連接*該分 壓電阻2 1 i及該電容2 2之_出端則與付費電話接地線 G N D相連接。 因該付費電話之話茼接地線GN D及電話線之接地線 E間被並接一電話後，該付費電話電路之該整流電路1 2 之輸出端之電壓值即明顯下降，是以，本發明利用此一現 (請先閩讀背面之注意事項再填寫本頁)Η Α7 Β7 Printed by the Central Laboratories of the Ministry of Economic Affairs of the Bayou Consumer Cooperatives 5. Description of the invention () Background of the invention: The present invention is a device and method for preventing theft of payphones, especially a four-wire telephone line. In general, by installing a voltage detection circuit and a ground wire cut-off circuit in the circuit of a pay phone, when a pay phone is abnormally connected by other phones *, regardless of whether the pay phone is in bark state, Both the central processing unit can actively detect whether there is a stolen call * and when it detects that the payphone is connected in parallel by other circuits, it will open the circuit of the payphone to prevent theft from making free calls. Previous skills: According to * Although China uses a two-wire telephone line as a medium for the connection between a telephone exchange and a pay phone, in other countries, such as the United Kingdom, a four-wire telephone line is used as a connection between the telephone exchange and a pay phone. Refer to the first picture * The four-line pay phone 9 0 傜 makes a call by inserting the IC card 9 0 0. However, if someone puts the ordinary telephone 7 0 telephone line 2 Tongnuo line 7 0 1 and 702 respectively Connected to the ground wire E of the four-wire telephone line 87 and the ground point 90 1 of the IC card 900, the IC card 900 can be dialed toll-free on the general telephone 70 after the IC card 900 is inserted into the pay phone 90 phone. Please refer to the second figure. If the ordinary telephone 70 bis call line 70 1 and 70 2 are respectively connected to the ground wire E of the four-wire telephone line 87 and the pay line 90 0 to 90 2 When GN D is connected, you can also make free calls on this general telephone 70. Please refer to the third picture, and learn about the circuit of the payphone 90 (please read the precautions on the back before filling this page) This paper uses the standard of the solid state in China {CNS) Α4 size (210 × 297) Printed by the Central Government Bureau of the Ministry of Economic Affairs and Consumer Cooperatives 424374 A7 B7 V. Description of the invention () RINGER CIRCUIT, an electromagnetic coupling / high-voltage protection circuit 9 1, a rectifier circuit 9 2, ~ Power circuit 93, a control circuit 94, an on / off circuit 95, and other telephone circuit components. The payphone 90 receives data from the telephone exchange via the ringer via the ringer control circuit. The electric signal from the line S; the three input terminals of the electromagnetic coupling / high-voltage protection circuit 91 are respectively connected to the two Nomobromones A_, B of the telephone line and the ground wire E. The electromagnetic coupling / high-voltage protection circuit The role of 9 1 is to pseudo-process the signals transmitted by these telephone lines A, B, and E for electromagnetic coupling and high-voltage input protection. After processing, the signals are transmitted to the two signal input terminals of the rectifier circuit 92; the rectifier The ground terminal of circuit 9 2 The ground wire of the telephone is connected to GND, and the signal output terminals of the rectifier circuit 92 are connected to the power circuit 9 3, the control circuit 9 4, the on / off circuit 95 and other circuit components .. The on / The input terminal of the circuit 9 5 is connected to the output terminal of the rectifier circuit 92; the control circuit 94 is provided with a telephone switch 94 1 and a resistor 9 4 2. The telephone switch 9 4 1 controls the payphone s 0 is in the Tonno state, the input of the microphone switch 94 1 is connected to the control signal connection I of a central processing unit, and the pay phone Sue can control the pay phone by the central processing unit 9 〇 Whether to call or not ° Please refer to the first figure again. When the four-line payphone 90 is connected to the general telephone 70, the general telephone 70 can borrow the call line of the pay telephone 90, and the general telephone 7 〇 Toll-free calling, so the circuit device of this conventional payphone 90 is obviously similar ^ In n ^ i 1 {Please read the precautions on the back before filling this page) This paper standard is applicable to Chinese family Standard rate (CNS > A4 size (210X W7 male ) Printed by the Central Laboratories Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives 4 2.5. Description of the Invention () When it is not ideal. The invention of the invention: The present invention is a device and method for preventing theft of payphones, which is used in payphones. A voltage detection circuit and a ground wire cut-off circuit are added to the circuit. After the payphone is stolen, the call loop can be opened and no more calls can be made. The principle of the invention is to use the center of the payphone The processing unit determines whether the voltage value of the voltage detection circuit drops abnormally. If the central processing unit detects that the voltage value of the voltage detection circuit drops abnormally, it can determine that the payphone has been stolen, then the The central processing army sent a signal through its control pin to open the circuit of the ground wire to prevent the payphone from being stolen and toll-free. In view of the fact that the communication technology of the conventional payphone can be used by other people to make free calls, and the inventor has finally developed the peptide deficiency and the relevant experience in manufacturing products based on years of careful observation and OT research. The purpose of the present invention is designed: The purpose of the present invention is to falsely raise a device and method for preventing theft of a payphone and a method thereof. 1) Add a voltage detection circuit and a ground wire to the payphone circuit. The voltage detection circuit is for the central processing unit in the payphone to detect whether the payphone has been stolen abnormally; if the central processing unit has detected that the payphone is stolen, the central processing unit Sheet (please read the precautions on the back before filling in this page) ^^^ 1 ϋι > t- ί- ·-—IJ---1--order --JI. This paper size applies the Chinese National Standard (CNS > A4 size (210X297 gong) Printed by B7 of the Central Standards Bureau of the Ministry of Economic Affairs and Consumer Cooperatives. V. Description of the invention () The yuan sends a signal to power off the relay that cuts off the circuit of the ground wire. At this time, the theft I ca n’t borrow the phone Toll free calls are made on the call line of the payphone S. In order to enable further recognition of the purpose, shape, and structure of the present invention and its effects, and to further understand and understand, the embodiments are described in conjunction with the drawings, which are described in detail below. : Brief description of the diagram: The first diagram shows the implementation of one of the connection lines between a telephone exchange and a payphone. Toll-free public telephone calls can be made. The second diagram is another connection between the telephone exchange and a payphone. The implementation of ss toll free public telephony. Figure 3 shows the detailed circuit diagrams of some public payphones and telephone lines. The fourth is a circuit diagram of the embodiment of the present invention. The first figure is to deter the implementation of the present invention. The detailed circuit diagram of the example. The sixth diagram is the operation flow chart of the present invention. The figure of the main components is explained: electromagnetic coupling / high voltage protection circuit 1 1 rectifier circuit 1 2 on / off circuit 1 3 control circuit 1 4 power circuit 1 5 voltage Detection circuit 2 0 Ground wire cut-off circuit 3 0 The present invention is a "device and method for preventing payment telephone from being stolen (please read the precautions on the back before filling this page) This paper applies National Standard (CNS) A4 specification (210X297 mm) Dubinzhuang mia 'A7 __B7_ of the Central Bureau of Standards of the Ministry of Economy Mi A' A7 __B7_ V. Description of the invention () J, please refer to the figure 4 Known as a ring control circuit (R INGER CIRCUIT), an electromagnetic coupling / high-voltage protection circuit 1 1, a rectifier circuit 12, an on / off circuit 13, a control circuit 1, 4, a power circuit 15, a central processing In the circuit of a four-wire payphone composed of a unit and other circuit elements, a voltage detection circuit 20 and a ground wire cut-off circuit 30 are additionally provided. The present invention actively detects this by using the central processing unit. Whether the voltage value of the voltage detection circuit 20 drops to determine whether the circuit of the payphone is connected with abnormal other telephones. If the central processing unit judges that the payphone and other telephones are connected, the central processing unit That is, a control signal is sent to cut the circuit 30 between the ground terminal of the rectifier circuit 12 and the payphone ground line GN D in order to prevent the four-wire payphone from being connected in parallel. Making free phone calls. The electric detection circuit 2 0 is connected between the input terminal of the rectifier circuit 1 ′ 2 and the ground line GND of the payphone, and is composed of a voltage dividing resistor 2 1 0, 2 1 1 and a capacitor 2 2. The input terminal 1 of the voltage dividing resistor 2 1 0 is connected to the output terminal of the rectifier circuit 12, and the output terminals of the voltage dividing resistor 2 1 ◦ are respectively connected to the voltage dividing resistor 2 1 1 and the capacitor 2 2 The input end is connected to the analog / digital converter of the central processing unit. The output end of the voltage dividing resistor 2 1 i and the capacitor 2 2 is connected to the payphone ground line GND. Because of the pay phone, the ground wire GN D and the ground wire E of the phone line are connected in parallel to a phone, the voltage value of the output terminal of the rectifier circuit 12 of the pay phone circuit is significantly reduced. Invented the use of this situation (please read the notes on the back before filling out this page)
本紙張尺度逍用中國國家標準（CNS ) A4規格（210X297公釐） 經濟部中央橾準局貝工消费合作社印装 A7 __B7_五、發明説明（） 象*令該中央處理葷元先將正常未被並接電話之該整流電 路1 2輸出端之電壓值予以儲存，當付費電話連線後f該 中央處理簞元之類比/數位轉換器搔與該電壓偵測電路2 0之一輸出端電壓相連接，並將所偵測到之輸出電壓端數 位化後，回傳至中央處理單元與原儲存之正常電壓值加以 比較，若該中央處理菫元經比較得知該電壓偵測電路2 0 所測得之電壓值不正常下降時，即甩判斷得知付費電話之 線路已不正常並接有其它話機。 就本賁施例而言，當付費電話並未並接有其它電話， 且該付費電話處於未通詰之狀態時，該電壓偵測電路2 0 中之接點C之電壓值約為5伏特左右，若付費電話通話時 >則接點C之電壓值約為1 · 5伏特左右；當該付費電話 並接有其它電話，則該付費電話在未通話之戕態時，該電 壓偵測電路2 0接點C之電壓值約降至1 ，5伏特左、右 |該付費電話在通話狀態下時•則該接點C之電壓约降至 0 ‘ 5伏特左右*故，利用本發明即可輕易偵測出該付費 電話被盗接之情形。 該接地線切斷電路30之輸入端係與該整流電路12 之接地端相連接，該接地線切斷電路3 0設有一與中央處 理單元之控剌接腳相連接之控制端，又，該接地線切斷電 路3 0之輸出端則與付費電話之接地線G N D相連接；該 接地線切斷電路30在本實施例中*係由一繼電器3 1、 —電晶體32及電阻33、34所組合而成，該繼電器3 1之輸入端傜與該整流罨路1 2之接地端相連接，該繼電 (請先閱讀背面之注意事項再填寫本頁) -袭- 訂 本紙張尺度適用中固國家標率（CNS ) A4说格（2丨ox297公釐） 42^74- at B7 經濟部中央標準局貝工消费合作社中裝 五、發明説明（） 器3 1之輸出端則與該電晶體3 2之集極端相建接，該電 晶體3 2之射極端則與付費電話電路之一電源端v A A相 連接’該電晶體3 2之基極端則與該電驵3 3之輸出端相 連接，並藉該電阻3 3之輸入端與該中央處理單元之該控 制接腳相連接。 當該付費電話經中央處理翬元偵測並判定電路中不正 常並接有其它話機之情肜時，則中央處理單元之該控制接 腳即發出訊號至該接地線切斷電路3 0之控制端，令接地 線切斷電路30開路，庳該整流電路1 2之接地端無法與 付費電胳中之接地線G N D相連接形成回路，使得該不正 常並接之電話無法盗打免費電話。 請參閱第五圈所示，本實施例中，當中央處理單元判 定電路中不正常並接有其它話槺之情形時，則該中央處理 翬元之該控制接腳即輸出一控制訊號至該接地線切斷電路 3 0之該電晶體3 2基極電阻3 3之_入端，令該電晶體 3 2由未導通之狀態轉爰成導通吠態，當該電晶體3 2導 通後，則集極端即產生一電壓值，逮導致該繼電器3 1跳 -開，則該整流電路1 2與接地線G N D間即形成開路，肽 時，該並接之其它電話即無法藉付費電話之通話回路盗打 免費電話。 請參閱第六圖所示，係本發明之動作流程，首先，該 中央處理單元先偵測該付費電話是否在通諾狀態，若在通 話狀態時，則該中央處理簞元即設定電壓偵測電路2 0之 接點C之電壓值為1汰特，同時與該中央處理單元之類比 1._L ——.---C丨 — (請先閲讀背面之注意事項再填寫本頁)This paper size is in accordance with the Chinese National Standard (CNS) A4 (210X297 mm), printed by the Central Laboratories Bureau of the Ministry of Economic Affairs and printed by the Bayer Consumer Cooperatives A7 __B7_ V. Description of the invention The voltage value of the output terminal of the rectifier circuit 12 that is not connected in parallel is stored. When the payphone is connected, the analog / digital converter of the central processing unit and one of the output terminals of the voltage detection circuit 20 are stored. The voltage is connected, and the detected output voltage terminal is digitized and then sent back to the central processing unit to compare with the original stored normal voltage value. If the central processing unit compares and learns that the voltage detection circuit 2 0 When the measured voltage drops abnormally, it is judged that the line of the payphone is abnormal and other phones are connected. According to this embodiment, when the payphone is not connected with other phones in parallel, and the payphone is in an unconnected state, the voltage value of the contact C in the voltage detection circuit 20 is about 5 volts. Left and right, if the pay phone is talking > the voltage value of contact C is about 1.5V; when the pay phone is connected with other phones, the voltage is detected when the pay phone is in a non-talk state. Circuit 2 The voltage value of contact C is reduced to approximately 1, 5 volts left and right | When the payphone is in a call state • the voltage of contact C is reduced to approximately 0 '5 volts * Therefore, the present invention is used You can easily detect that the payphone has been stolen. The input terminal of the ground wire cutting circuit 30 is connected to the ground terminal of the rectifier circuit 12, and the ground wire cutting circuit 30 is provided with a control terminal connected to the control pin of the central processing unit. The output end of the ground wire cut-off circuit 30 is connected to the ground line GND of the payphone; in this embodiment, the ground wire cut-off circuit 30 is composed of a relay 31, a transistor 32 and The combination of resistors 33 and 34, the input terminal 继电器 of the relay 3 1 is connected to the ground terminal of the rectifier circuit 12, the relay (please read the precautions on the back before filling this page) This paper scale is applicable to the National Solid Standard Standard (CNS) A4 scale (2 丨 ox297 mm) 42 ^ 74- at B7. The Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives. The terminal of the transistor 32 is connected to the collector terminal of the transistor 32, and the emitter of the transistor 32 is connected to a power terminal v AA of the payphone circuit. The base terminal of the transistor 32 is connected to the transistor. The output terminal of 3 3 is connected, and the input terminal of the resistor 3 3 is connected to the control pin of the central processing unit.相 连接。 Phase connection. When the payphone is detected and determined by the central processing unit to be abnormal in the circuit and connected to other phones, the control pin of the central processing unit sends a signal to the ground wire to cut off the circuit 30. The control terminal makes the ground wire cut-off circuit 30 open, and the ground terminal of the rectifier circuit 12 cannot be connected to the ground wire GND in the pay circuit to form a loop, so that the abnormally connected phone cannot make free calls. . Please refer to the fifth circle. In this embodiment, when the central processing unit determines that the circuit is abnormal and other words are connected, the control pin of the central processing unit outputs a control signal to the The ground wire cuts off the input terminal of the transistor 3 2 base resistor 3 3 of the circuit 3, so that the transistor 32 is turned from a non-conducting state to a conducting bark state. When the transistor 32 is turned on, Then, a voltage value is generated at the set terminal, which causes the relay 31 to jump-open, and an open circuit is formed between the rectifier circuit 12 and the ground line GND. In the case of a peptide, the other connected phones cannot borrow a pay phone. Call loop toll free calls. Please refer to the sixth figure, which shows the operation flow of the present invention. First, the central processing unit first detects whether the pay phone is in the tonno state. If it is in the call state, the central processing unit sets voltage detection. The voltage value of the contact C of the circuit 2 0 is 1 Tie, and is analogous to the central processing unit 1._L ——.--- C 丨 — (Please read the precautions on the back before filling this page)
•1T 本紙張尺度逍用中國國家標準（CNS ) A4规格（210X297公釐） 7 4'" A7 B7 五、發明説明（） /數位轉換器直接從電路上取得之C點電Μ值加K比較> 若C點之電壓值小於1伏特時，則該中央處理里元即發出 一訊號，俾藉該訊號令該接地線切斷電路3 0之該繼電器 3 1開路，令盗接之電話無法撥打免費電話，若該中央處 理單元判斷該C點電壓值與1伏特之正常電膣值相當時， 則仍保持付費電話在正常工作狀態。 若該付費電話並未在通話狀態時，該中央處理單元則 設定C點之電壓值為5伏特*並Μ 5伏特電壓與該類比/ 數位轉換器直接從電路上所測取得之C點電壓值加以比較 ，若經中央處理單元偵測該C點之電壓值小於5伏持時， 則該中央處理覃元即發出訊號令接地線切新電路3 0開路 ，若經中央處理單元偵測該C點之電壓值為5伏特時，則 該付費電話仍保持在正常工作狀態。 按*以上所述，僅為本發明最佳之一具體窖腌例，惟 本發明之構造特徵並不侷限於此，任何熟悉該項技藝者在 本發明領域内，可輕易思及之變化或修飾，皆可涵蓋在Μ 下本案之專利範圍。 (請先閲讀背面之注意事項再填寫本頁) \袈· 訂 經濟部中央梂率扃貝工消费合作社印氧 本紙張尺度適用中國國家捸準（CNS ) A4洗格（2丨0X297公釐）• 1T This paper size is in accordance with the Chinese National Standard (CNS) A4 specification (210X297 mm) 7 4 '" A7 B7 V. Description of the invention () / Digital converter directly obtains the value of point C from the circuit plus the value of K Comparison > If the voltage value of point C is less than 1 volt, the central processing unit sends a signal, and the signal is used to make the ground wire cut off the circuit 30 and the relay 31 is open, so that it is stolen. The phone cannot make a toll-free call. If the central processing unit determines that the voltage value at point C is equal to the normal electrical value of 1 volt, the pay phone will remain in a normal working state. If the payphone is not in a call state, the central processing unit sets the voltage value at point C to 5 volts * and the voltage at point C is measured by the analog / digital converter directly from the circuit By comparison, if the voltage value of point C detected by the central processing unit is less than 5 volts, the central processing unit sends a signal to the ground line to open a new circuit 30, and if the central processing unit detects the C When the voltage value of the point is 5 volts, the pay phone remains in a normal working state. According to the above description, it is only one of the best specific examples of the present invention. However, the structural features of the present invention are not limited to this. Anyone skilled in the art can easily consider the changes or Modifications can all cover the patent scope of this case under M. (Please read the precautions on the back before filling in this page) \ 袈 · Order Printed oxygen by the Central Ministry of Economic Affairs and the Bayer Consumer Cooperative Co., Ltd. This paper size is applicable to China National Standard (CNS) A4 Washing (2 丨 0X297 mm)