五、發明説明（1) 發明背景 本發明關於使用感應馬逹的門裝置，特別是開於適於 設有門閉合器之電梯門的馬達驅動門裝置。 諸如掲示於JP—A—55—89182 (1980 )的傳统馬達電梯門裝置包含DC馬達並聯電阻器的電路 ，若中斷馬達電源，則由DC馬逹的再生制動將制動力施 於門上。再者，JP (U) —B — 53 — 12033 ( 1978)掲示馬達驅動門裝置，其中若供電業務中斷， 則感應馬逹（電容式馬達）接到獨立的D C源預定時間， 以防乘客被門困住且防止門毀壊。 使用DC馬達之先述的傳統馬達驅動電梯門裝置適於 防止電梯門空轉，若供電業務中斷，則確保電梯乘客安全 然而，因DC馬逹需依據磨損來更換電刷，所以DC 馬達的控制性好，但維修性不佳。因此，配合應用於感應 馬達之換流器控制科技的近來發展，最好使用堅固且免維 修的感應馬達達於此種馬達驅動電梯門裝置。 再者，第二個提到的傳統馬達驅動門裝置使用分離的 DC電源（電池）而非購買的電源，造成麻煩之電池維修 的缺點。 發明概要 本發明的目標是對使用感應馬逹的馬逹驅動門裝置提 供在供電業務中斷時之容易維修的門空轉防止裝置。 Ϊ 背 .而 之 注 意 事 項 經濟部屮央標準局Α工消货合作社印ft,,4 本紙張尺度逍用中a Η家《準(CNS) Ή規格（210X297公放） S1. 2. 20,000 .1¾ Λ 6 Π 6 五、發明説明（2 ) 依據本發明的一觀點，使用三相感應馬達做為驅動源 的馬達驅動門裝置包括電源通電時充電的電容器，以及供 電業務中斷時將電容器接到感應馬達的設備。 依據本發明另一觀點，馬達驅動門裝置包括AC電源 ，將AC轉換成DC的轉換器，接到轉換器輸出侧的電容 器，將DC轉變成三相AC的換流器，由換流器饋電來驅 動門的三相感應馬逹，另包括供電業務中斷時將電容器接 在感應馬達輸入端之間的設備。 當電源通電時充入電容器的電供電業務中斷時經由 門驅動感應馬逹放電。供電業務中斷時，假設門在關或開 的途中，則門移入空轉狀態，門的移動速度會增加。然而 ，來自電容器的放電電流流入感應馬逹而引發DC制動， 以抑制增加的門移動速度，藉以安全且穩定的移動速度來 逹成門開啓及閉合作用。 依據本發明另一觀點，當電源通電時，接到在轉換器 與換流器間之DC中間電路的電容器充電，供電業務中斷 時，在短時間内朝感應馬達放電。鑒於供電業務中斷後之 維修時的安全，事實上最好在預定時間内將電容器中的電 放電。使用上述的放電電流，以簡化的裝置防止門空轉， 以及提高維修時的安全。 圖式簡述 圖1是依據本發明之馬達驅動門裝置之實施例的組合 圖； 本紙張尺度边用中國明家«毕(CNS) T4規格(210x297公;it) -4 意 事 項5. Description of the invention (1) Background of the invention The present invention relates to a door device using an induction horse, especially a motor-driven door device which is suitable for elevator doors provided with a door closer. A conventional motor elevator door device such as shown in JP-A-55-89182 (1980) includes a circuit in which a DC motor is connected in parallel with a resistor. If the power supply to the motor is interrupted, the regenerative braking by the DC horse applies the braking force to the door. Furthermore, JP (U) —B — 53 — 12033 (1978) shows a motor-driven door device, where if the power supply service is interrupted, the induction horse (capacitive motor) is connected to an independent DC source for a predetermined time to prevent passengers from being caught The door is trapped and prevents the door from ruining. The conventional motor-driven elevator door device that uses the DC motor mentioned above is suitable to prevent the elevator door from idling. If the power supply service is interrupted, it will ensure the safety of the elevator passengers. However, because the DC horse needs to replace the brushes according to wear, the DC motor has good control , But poor maintainability. Therefore, in conjunction with recent developments in inverter control technology applied to induction motors, it is best to use robust and maintenance-free induction motors for such motor-driven elevator door devices. Furthermore, the second mentioned traditional motor-driven door device uses a separate DC power supply (battery) instead of the purchased power supply, which causes the disadvantage of troublesome battery maintenance. SUMMARY OF THE INVENTION An object of the present invention is to provide a door slip prevention device that is easy to maintain when a power supply service is interrupted for a horse-operated door device that uses an induction horse. Ϊback. And the matters needing attention The Ministry of Economic Affairs Standards Bureau A Industrial Consumer Goods Cooperative printed ft ,, 4 paper standards for easy use a Η home "quasi (CNS) Ή specifications (210X297 public release) S1. 2. 20,000. 1¾ Λ 6 Π 6 V. Description of the invention (2) According to one aspect of the present invention, a motor drive door device that uses a three-phase induction motor as a driving source includes a capacitor that charges when the power supply is turned on, and connects the capacitor when the power supply service is interrupted. Induction motor equipment. According to another aspect of the present invention, the motor-driven door device includes an AC power source, a converter that converts AC to DC, a capacitor connected to the output side of the converter, and a converter that converts DC to three-phase AC, which is fed by the converter The three-phase induction horse that drives the door by electricity, and also includes equipment that connects the capacitor between the input terminals of the induction motor when the power supply service is interrupted. When the power supply service of the capacitor is interrupted when the power supply is energized, the gate drive induces a discharge. When the power supply service is interrupted, assuming that the door is in the process of closing or opening, the door moves into the idling state, and the moving speed of the door will increase. However, the discharge current from the capacitor flows into the induction horse and causes DC braking to suppress the increased door movement speed, thereby achieving the door opening and closing effect with a safe and stable movement speed. According to another aspect of the present invention, when the power supply is energized, the capacitor connected to the DC intermediate circuit between the converter and the converter is charged, and when the power supply service is interrupted, it is discharged toward the induction motor in a short time. In view of the safety during maintenance after the interruption of the power supply business, in fact, it is best to discharge the electricity in the capacitor within a predetermined time. The use of the above-mentioned discharge current prevents the door from idling with a simplified device and improves safety during maintenance. Brief Description of the Drawings Figure 1 is a combined diagram of an embodiment of a motor-driven door device according to the present invention; the paper size is based on the Chinese Mingjia «Bi (CNS) T4 specification (210x297 g; it) -4 Item
Li £ 經：外部中央榀準而只工消伢合作社印製 S1. 2. 20,000 Λ 6 Π 6 025^2 五、發明説明（3 )Li £ Classic: Printed by the external central authority and printed only by the Cooperative Societies S1. 2. 20,000 Λ 6 Π 6 025 ^ 2 5. Description of the invention (3)
(請先背‘之注意节項Y A 圖2是從馬達驅動門裝置的地板側所見之電梯門的機 械結構； 圖3是從上側所見者； 圖4是馬逹驅動門裝置之門閉合器之門閉合力的特性 圖； 圖5是顯示依據本發明之實施例之門控制之微電腦之 部分程式的流程圖； 圖6是流入馬達驅動門裝置之感應馬逹之DC制動電 流的波形； 圖7是顯示依據本發明之馬達驅動門裝置之另一實施 例的組合圖； 圖8是顯示依據本發明之馬達驅動門裝置之另一實施 例的組合圖； 實施例詳述 下文參照圖式來解釋本發明的實施例。 經濟部屮央櫺準局貝工消伢合作社印製 圖1是應用於電梯門裝置之本發明實施例的組合圔。 三相電源1的AC由轉換器2轉換成DC。在被濾波 電容器3濾波後，整流的輸出饋至換流器4。換流器4供 應可變電壓和可變頻率的三相AC至三相感應馬逹5。 控制單元6控制換流器4,設有撤電腦，包含諸如徹 V 一 ...... 處理單元（MPU) 60 1、隨機存取記億（RAM) 602、唯讀記億（ROM) 603、輸入及輸出介面（ I/O) 604,另設有MPU監控電路605,包含諸 SI. 2. 20.000 本紙张尺度逍用中甬Η家楳毕（CNS)T4規格(210x297公龙） -5 - A 6 Π 6 五、發明説明（4 ) 如監控MPU 601的監視定時器、供電業務中斷偵測 電路606、驅動換流器4之電晶體4 1和42的基本驅 動電路6 0 7。 饉電器7受控制單元6所控制，包含開路接點7 b 1 一 7b3。濾波電容器3經由接點7b 1和7b2及電狙 器8而接在感應馬達5的兩條輸入線之間。 參照圖2和3來解釋感應馬逹5所驅動的電梯門。 圖2是從前面所見之電梯門的内部機械結構，圖3是 從上面所見者。 經济部屮央標準^β工消伢合作社印^ 經由三相感應馬逹5的旋轉，在1 1和1 2之間延伸 的循環鏈經由鏈10而移動，打開及關閉電梯廂側門14 和1 5。當電梯廂1 6到達預定起落區之内時，廂側門 1 4和1 5及地板側門1 8和1 9經由嚙合裝置1 7而一 起開啓及閉合。本實施例中，門閉合器彈簧2◦黏在其中 一値地板側門1 8和1 9 ,門閉合力施於門，根據圖4的 門位置而爱。門閉合器彈簧20是不可或缺的裝置，當廂 16不在地板上時，用來可靠地閉合地板側門，以防地板 上的乘客掉入電梯移動管道。 門閉合力總是施於地板側門1 8和1 9的此種電梯門 裝置中，當供電業務中斷且來自感應馬達5的驅動轉矩在 門閉合途中消失時，藉著門閉合器彈簧20的張力，門加 速並碰撞另一門的端部。因此産生困擾乘客之大的門碰撞 磬，且當乘客夾在門之間時，碰撞力大且危險。 為了上述問題，依據圖1之本發明的實施例，DC制 S1. 2. 20,000 Μ 請 背 r而 注 意 項 ι4 本紙張尺度逍用中a國家«毕(CNS)T4規格(210x297公釐） -6 ，02從 Λ 6 Π 6 經濟部屮央梂準而β工消伢合作社印31 五、發明説明（5 ) 動施於馬達5以限制門閉合速度。 圖5顯示關於圖1之徹電腦之作業程式的流程圖。 首先，經由常執行的定時器中斷，程式在步驟501 開始，在步驟5 0 2判斷是否有供電業務中斷，當判斷存 在供電業務中斷時，在步驟503判斷MPU 60 1是 否正常，當判斷MPU 601正常時，程序移到步驟 5 04以瀲勵繼電器7。隨後，在步驟5 0 5判斷繼電器 7和接點7b1—7b3是否正常。亦即，當繼電器7激 勵時，必須已打開開路接點7b3,因而觀察接點7b3 的開啓和閉合狀況來判定正常性。當判定正常時且若輸出 繼電器7的故障信號TB,則在步驟506停止信號输出 ，在步驟507完成處理。 此時，回應於在預定樓之電梯廂16的到達，依據處 理流程（未囫示）來提供開門命令，來自MPU 601 的PWM信號經由基本驅動電路6 0 7供至換流器4。因 此換流器4經由預定的PWM控制而速度控制感應馬達5 ,門抗衡門閉合器彈簧20的力而平滑開啓。再者，在預 定時間經過後或經由關門鈕的作用而提供關門命令時，門 經由感應馬達5的速度控制而開始平滑閉合。 ί假設門在密合途中時發生供電業中陵tl圖1的供電業 務中斷偵測電路606産生信號，在圖5的步驟502被 感測，然後程序移到步驟5 0 8將繼電器7去能，在步驟 5〇9輸出閘極抑制信號到構成換流器4的電晶體4 1和 42,停止換流器4的作用。因此，停止換流器4的作用 本紙51尺度边用中B B家楳準(CNS)<F4規格(210x297公龙) S1. 2. 20,000 -7 -(Please memorize the section YA first) Figure 2 is the mechanical structure of the elevator door seen from the floor side of the motor-driven door device; Figure 3 is seen from the upper side; Figure 4 is the door closer of the horse-driven door device Characteristic diagram of the door closing force; FIG. 5 is a flowchart showing a part of the program of the microcomputer for door control according to an embodiment of the present invention; FIG. 6 is a waveform of the DC braking current flowing into the induction horse of the motor-driven door device; FIG. 7 is A combined diagram showing another embodiment of the motor-driven door apparatus according to the present invention; FIG. 8 is a combined diagram showing another embodiment of the motor-driven door apparatus according to the present invention; Embodiment of the invention. Figure 1 is a combination of the embodiment of the present invention applied to the elevator door device. The AC of the three-phase power supply 1 is converted by the converter 2 into DC. After being filtered by the filter capacitor 3, the rectified output is fed to the inverter 4. The inverter 4 supplies variable voltage and variable frequency three-phase AC to three-phase induction horse 5. The control unit 6 controls the inverter 4 , With a withdrawal computer, Contains such as through V ... Processing Unit (MPU) 60 1, Random Access Memory (RAM) 602, Read Only Memory (ROM) 603, Input and Output Interface (I / O) 604, another Equipped with MPU monitoring circuit 605, including all SIs. 2. 20.000 The paper standard is used in Xiaoyongzhongjia (CNS) T4 specification (210x297 male dragon) -5-A 6 Π 6 5. Description of the invention (4) Monitor timer for monitoring MPU 601, power supply service interruption detection circuit 606, basic drive circuit 6 0 7 for driving transistors 4 1 and 42 of converter 4. Electrical appliance 7 is controlled by control unit 6, including open contacts 7 b 1-7b3. The filter capacitor 3 is connected between the two input lines of the induction motor 5 via the contacts 7b 1 and 7b2 and the electric sniper 8. The elevator driven by the induction horse 5 is explained with reference to FIGS. 2 and 3 Door. Figure 2 is the internal mechanical structure of the elevator door seen from the front, and Figure 3 is seen from above. The Ministry of Economic Affairs Standard ^ β 工 消 伢 Cooperative Society ^ By three-phase induction Ma 5 rotation, in 1 1 The endless chain extending between and 12 moves through the chain 10 to open and close the elevator car side doors 14 and 15. When the elevator car 16 reaches the predetermined landing zone At this time, the car side doors 14 and 15 and the floor side doors 18 and 19 are opened and closed together through the engagement device 17. In this embodiment, the door closer spring 2 is stuck to one of the floor side doors 18 and 1 9. The door closing force is applied to the door, which is loved according to the door position of Fig. 4. The door closer spring 20 is an indispensable device. When the compartment 16 is not on the floor, it is used to reliably close the floor side door to prevent the floor Of passengers fall into the elevator moving duct. The door closing force is always applied to such elevator door devices of floor side doors 18 and 19. When the power supply service is interrupted and the driving torque from the induction motor 5 disappears during the door closing, By the tension of the door closer spring 20, the door accelerates and hits the end of the other door. Therefore, a large door collision chimney that afflicts passengers occurs, and when the passengers are caught between the doors, the collision force is large and dangerous. To solve the above problem, according to the embodiment of the present invention shown in FIG. 1, DC manufactures S1. 2. 20,000 Μ Please note the item ι4 The paper size is used in a country «Bi (CNS) T4 specification (210x297 mm)- 6, 0.02 from Λ 6 Π 6 The Ministry of Economic Affairs and the Central Standards and the β Industrial Consumer Cooperatives printed 31. 5. Description of the invention (5) The motor 5 is applied to limit the door closing speed. FIG. 5 shows a flow chart of the operating program of the FIG. 1 computer. First, through the timer interrupt that is frequently executed, the program starts at step 501. At step 502, it is determined whether there is a power supply service interruption. When it is determined that there is a power supply service interruption, it is determined at step 503 whether the MPU 60 1 is normal. When the MPU 601 is determined When normal, the program moves to step 5 04 to energize relay 7. Subsequently, at step 505, it is judged whether the relay 7 and the contacts 7b1-7b3 are normal. That is, when the relay 7 is energized, the open contact 7b3 must have been opened, so observe the opening and closing of the contact 7b3 to determine normality. When the determination is normal and if the fault signal TB of the relay 7 is output, the signal output is stopped in step 506, and the processing is completed in step 507. At this time, in response to the arrival of the elevator car 16 in the predetermined building, the door opening command is provided according to the processing flow (not shown), and the PWM signal from the MPU 601 is supplied to the inverter 4 via the basic drive circuit 607. Therefore, the inverter 4 speed-controls the induction motor 5 via predetermined PWM control, and the door opens smoothly against the force of the door closer spring 20. Furthermore, when a door closing command is provided after a predetermined time has elapsed or through the action of the door closing button, the door starts to close smoothly via the speed control of the induction motor 5. ίAssuming that the door is on the way to close, the power supply business interruption detection circuit 606 of FIG. 1 generates a signal, which is sensed in step 502 of FIG. 5, and then the program moves to step 5 0 8 to disable relay 7. At step 509, a gate suppression signal is output to the transistors 41 and 42 constituting the inverter 4, and the function of the inverter 4 is stopped. Therefore, the function of the inverter 4 is stopped. The 51-size side paper of this paper is used in the B BB family standard (CNS) < F4 specification (210x297 male dragon) S1. 2. 20,000 -7-
fJ Λ 6 Β6 五、發明説明（6 ) ih ；m in 背 、而 之 注 意 事 項 US-\ ，同時，接點7b1和7b2閉合，經由圖1的濾波電容 器3、電阻器8、接點7b 1、感應馬逹5、接點7b2 及濾波電容器3而構成閉路，濾波電容器3中的充電經由 感應馬達而放電，對於命波電容器3，放電電流i b流動 ，對於感應馬達，DC制動電流i b流動。 圖6顯示DC制動電流對時間的變化。DC制動電流 的大小依電容器3之電容和電阻器8之電阻所決定的時間 常數而變，藉由選擇濾波電容器3之電容的適當量及電阻 器8之電阻的適當量，得到諸如曲線i b 1和i b2的電 流。實際應用中，當開或關門時間約2秒時，約1秒之 DC制動電流的期間令人滿意，因為曲線i b 1所代表的 DC制動電流較佳。 現在，回到圖5,當感測監控電路605的輸出而在 步驟503測到MPU 60 1的異常時，以上述的相同 方式，程序移到步驟5 08和509,停止換流器4的作 用且DC制動施於馬達5以確保安全。 經濟部屮央標準局Α工消费合作社印製 随後，當在步驟505測到接點7b3熔化所造成之 接點7b3之作業模式的異常時，在步驟510停止換流 器4的作用，繼電器7的故障信號TB在步驟511輸出 到電梯控制單元9。因此，繼電器7的故障信號存在電梯 控制單元9,立刻分析電梯故障的原因，因而得到具有良 好維修性之可靠的門裝置。 依據上述實施例，供電業務中斷時，産生對門驅動感 應馬逹5的DC制動轉矩，除了購買的AC電源1之外， 本紙張尺度逍用中曲《家猱準(CNS) Y4規格(2丨0x297公:¢) S1. 2. 20,000 Λ 6 Η 6 五、發明説明（7 ) 毋需提供諸如電池之獨立的緊急使用電源，因此得到具有 良好維修性及簡單結構和經濟生産成本的馬達驅動門裝置fJ Λ 6 Β6 V. Description of the invention (6) ih; min in the back, and the matters needing attention US- \, at the same time, the contacts 7b1 and 7b2 are closed, through the filter capacitor 3, resistor 8, contact 7b 1 of FIG. 1 , The induction horse 5, the contact 7b2 and the filter capacitor 3 form a closed circuit, the charge in the filter capacitor 3 is discharged via the induction motor, the discharge current ib flows to the life wave capacitor 3, and the DC brake current ib flows to the induction motor. Figure 6 shows the DC braking current as a function of time. The magnitude of the DC braking current varies according to the time constant determined by the capacitance of the capacitor 3 and the resistance of the resistor 8, by selecting the appropriate amount of the capacitance of the filter capacitor 3 and the appropriate amount of the resistance of the resistor 8, a curve such as curve ib 1 is obtained And i b2 current. In practical applications, when the door opening or closing time is about 2 seconds, the period of the DC braking current of about 1 second is satisfactory because the DC braking current represented by the curve i b 1 is better. Now, returning to FIG. 5, when the output of the monitoring circuit 605 is sensed and an abnormality of the MPU 60 1 is detected in step 503, in the same manner as described above, the program moves to steps 5 08 and 509 to stop the role of the inverter 4. And DC braking is applied to the motor 5 to ensure safety. Printed by the Industrial and Commercial Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs. Then, when an abnormality in the operating mode of the contact 7b3 caused by the melting of the contact 7b3 is detected at step 505, the function of the inverter 4 is stopped at step 510 The fault signal TB of 7 is output to the elevator control unit 9 in step 511. Therefore, the failure signal of the relay 7 exists in the elevator control unit 9, and the cause of the elevator failure is immediately analyzed, thereby obtaining a reliable door device with good maintainability. According to the above embodiment, when the power supply service is interrupted, a DC braking torque for the door drive induction horse 5 is generated. In addition to the AC power supply 1 purchased, the paper-scale Xiaoqu tune "CNS Y4" (2丨 0x297 public: ¢) S1. 2. 20,000 Λ 6 Η 6 5. Description of invention (7) No need to provide independent emergency power supply such as battery, so motor drive with good maintainability, simple structure and economic production cost is obtained Door device
先 m in 背 •而 之 注 意 項 I A 〇 再者，除了供電業務中斷時將濾波器3 (使轉換器2 的整流輸出平滑）的電放電到感應馬達5以消除提供獨立 的緊急使用電源之上述優點之外，利用維修時鑒於安全而 在供電業務中斷時必須放電之濾波電容器3中的電，逹成 不需獨立放電電路的顯著優點。 圖7是本發明另一實施例。 只說明與圖1之實施例不同的部分。提供單相轉換器 21和DC制動專用電容器22,獨立於主電路中的轉換 器2和濾波電容器3之外。因此，提供放電電阻器23, 供電業務中斷時，在預定時間内，主電路之濾波電容器3 中的電經由其而放電，以保維修人員的安全。 本實施例中，也消除諸如獨立緊急使用電源的需要， 因此馬達驅動門裝置的結構簡單、生産成本經濟且維修性 顯著。 經濟部屮央標準而A工消仲合作社印製 圖8是本發明另一實施例。 圔中，只說明與圖1之實施例不同的部分。顯示構成 換流器4的所有電晶體4 1 一 46及二極體4 1 1 一 4 6 1 ,其中加入將換流器電路的一相位的一]E $短路的 题流腾2 4，及將不同相位的一負臂短路的另一閘流體 - - - · ·"* '：··'''· ....... » ... 2 5。’ 加入控制電路6的點火電路6 0 8激發閘流體2 4和 本紙ft尺度边用中BH家«準(CNS)T4規格(210><297公;》:> S1. 2. 20,000 -9 - Λ 6 Ιί 6 202挪 五、發明説明（8 ) 2 5。點火電路6 0 8産生點火脈衝，回應於供電業務中 斷偵測電路606的輸出。所以，當供電業務中斷時，來 自濾波電容器3的放電電流，易言之，感應馬達5的DC 制動電流i b,流經由濾波電容器3、電阻器8、閘流體 24、感應馬達5、閘流體2 5所形成的閉路。閘流體 24和25由單一脈衝來激發，在濾波電容器3中的電大 致放電後，由本身來熄滅。由於單一脈衝便足以激發閘流 體，所以即使在測到供電業務中斷後，包含在點火電路 6 0 8之電容器（未圖示）中所充的電也可靠地激發閘流 體24和25,確實使做為制動電流的放電電流i b流入 感應馬逹5。 依據本發明，提供具有感應馬達做為驅動源的馬達驅 動門裝置，包含門超速防止裝置，供電業務中斷時，具有 簡單構造、經濟生産成本及良好維修性。 再者，依據本發明另一觀點，包含感應馬達以驅動經 由轉換器、濾波電容器和換流器來饋電之門的馬達驅動門 裝置中，藉著將濾波電容器中的電放電到感應馬逹，放電 設備做為DC制動轉矩産生設備，藉以提供具有更增進之 結構簡化、生産成本經濟和維修性的馬逹驅動門裝置。 本紙張尺度逍用中《«家«毕(CNS)T4規格(210x297公；¢) -10 -閲 in 背 而 ，之 注 意 項 £ 經濟部屮央榀準局C5工消件合作社印製 51. 2. 20f000Min in first • Note IA 〇 Furthermore, except for the interruption of the power supply service, the electricity of the filter 3 (smoothing the rectified output of the converter 2) is discharged to the induction motor 5 to eliminate the above provision of independent emergency power supply In addition to the advantages, the use of the electricity in the filter capacitor 3 that must be discharged when the power supply service is interrupted due to safety during maintenance is a significant advantage that does not require an independent discharge circuit. 7 is another embodiment of the present invention. Only the parts that differ from the embodiment of FIG. 1 will be described. The single-phase converter 21 and the DC braking dedicated capacitor 22 are provided independently of the converter 2 and the filter capacitor 3 in the main circuit. Therefore, the discharge resistor 23 is provided, and when the power supply service is interrupted, the electricity in the filter capacitor 3 of the main circuit is discharged through it within a predetermined time to ensure the safety of maintenance personnel. In this embodiment, the need for independent emergency power supply is also eliminated, so the structure of the motor-driven door device is simple, the production cost is economical, and the maintainability is remarkable. Printed by the Ministry of Economic Affairs and printed by A Gongxiaozhong Cooperative Society. Figure 8 is another embodiment of the present invention. Only the parts that differ from the embodiment of FIG. 1 are described. Show all the transistors 4 1-46 and diodes 4 1 1-4 6 1 that make up the inverter 4, which includes the problem of short circuiting one phase of the converter circuit] E $ short circuiting the current flow 24, and Another thyristor that short-circuits a negative arm of a different phase---·· " * ': ··' '' · .................. 2 5. 'Ignition circuit 6 0 8 added to the control circuit 6 excites the thyristor 24 and the ft scale side of the paper BH home «quasi (CNS) T4 specifications (210> < 297 public;》: > S1. 2. 20,000- 9-Λ 6 Ιί 6 202 Shift 5. Description of the invention (8) 2 5. The ignition circuit 6 0 8 generates ignition pulses in response to the output of the power supply service interruption detection circuit 606. Therefore, when the power supply service is interrupted, it comes from the filter capacitor The discharge current of 3, in other words, the DC braking current ib of the induction motor 5, flows through the closed circuit formed by the filter capacitor 3, the resistor 8, the thyristor 24, the induction motor 5, and the thyristor 25. The thyristors 24 and 25 It is excited by a single pulse, and after the electricity in the filter capacitor 3 is substantially discharged, it is extinguished by itself. Since a single pulse is enough to excite the thyristor, even after the power supply service interruption is measured, the capacitor included in the ignition circuit 608 The electricity charged in (not shown) also reliably excites the thyristors 24 and 25, and indeed causes the discharge current ib as a braking current to flow into the induction horse 5. According to the present invention, a motor having an induction motor as a driving source is provided Door drive, including The overspeed prevention device has a simple structure, economical production cost, and good maintainability when the power supply business is interrupted. Furthermore, according to another aspect of the present invention, it includes an induction motor to drive the power fed through the converter, filter capacitor, and inverter In the motor-driven door device of the door, by discharging the electric power in the filter capacitor to the induction horse, the discharge device is used as a DC braking torque generating device, thereby providing a horse with more simplified structure, economical production cost and maintainability The drive door device. This paper standard is used in the "Home" (CNS) T4 specification (210x297 g; ¢) -10 -Read in the contrary, the items of attention. The Ministry of Economic Affairs, Central Bureau of Accreditation C5 Printed by the cooperative 51. 2. 20f000