(完整版)自制的电火花穿孔机

1、自制的电火花穿孔机转贴的，我也回答不了具体总体。感谢 Zhang56 网友提供的电路图。电火花打小孔工具摆轮是手表最重要部件, 其上下两个轴尖因不停来回转动, 在润滑不良情况下, 很易磨损 , 一些老旧表特别是无防震功能的老怀表更是主要损坏件之一,修复方法主要有:1; 更换整个摆轮有原厂摆轮最好, 但要注意其惯性距要一样, 不然在调整走时快慢会有麻烦, 最好是连游丝（ 整个震荡系统） 一同更换 2; 锡焊摆轴尖,早年有配件厂专生产一种轴尖, 状如铆钉 , 先将旧轴适当磨短, 然后将轴尖大头与摆轴锡焊接 , 但焊后很难达到同轴度要求, 摆轮容易变色不是好办法 3; 碰焊法 ; 该法除要求焊接规范

2、（ 压力 , 电流 , 时间 ） 参数适当外, 还有一大缺点 , 就是摆轴材质为炭素工具钢（相当于国内牌号T10A）由於含炭高，焊核因急剧冷却导致晶粒粗大，内应力增加 , 硬和碎都给后期修磨轴尖带来困难 , 该法在工业中只适用於低炭钢和镍合金如不锈纲等材质4; 只更换摆轴 , 此法更多缺点 , 由於摆轴除与摆轮配合, 还要与游丝, 下摆碟配合 , 在冲下旧摆轴和铆合新摆轴时, 极易将摆轮弄变形, 给后续调较带来更多问题 , 如果不是原厂配件, 则更不宜采用 5;裁轴尖 （广东人叫种车芯）方法是在已断轴尖根部打钻一小孔, 压打入小钢丝, 有时孔深不够还要焊锡以求牢固 , 优点是影响部位小 , 原

3、断处下部凸台可作参考点 , 手艺好的师傅修后一般难以看出差别 , 缺点是需对摆轴退火, 温度不足难钻孔, 温度过高镀金摆轮将变色, 钻头难磨 , 如果折断钻头则麻烦大了 !早年搞了个电火花打孔工具, 上图与朋友交流由于要打之孔很小，又是盲孔，不能用晶体管电路，只能用原始的RC电路，变压器功率为10W输出电压40VDC,50VDC§挡，电容为金属化纸介电容，分0.01nF.0.22nF.0.47nF 按要求组合工具1基座为后置导柱.周界为80x80模架，稳定性高可保证电极与摆轮工作时的垂 直度和平行度要求1；为电极头,用DQKt磁先导伐改装,线圈不变由220VAC供电,下部静铁芯长度比

4、线圈长度一半再少1.5mm,中间有孔，压装于线圈导磁套内，上部动铁芯长度一样，但外径少1.5mm,端部装轴承,由0.15mm3J1恒弹性十字簧片固定于线圈外壳，下部也有轴承，同样由十字簧片固定干外壳，转轴由两轴承支承，下部为夹头，夹持紫铜电极，上端有小皮带轮，也是导电入口，再由220VAC/500转同步电机带动，整个电极头垂直装于上模扳，并与之绝缘，工作时电极边旋转边上下震动2;为旋转平台，内有轴承，外部装有煤油承液盘，摆轮平放干平台上，由一金属环通过三个簧片以重力轻压摆轮，使其导电，整个平台垂直装于下模板上，并与上电极同轴3；为电极修正器，装于下模扳，可作水平摆动和固定，旋转手轮可使电极座3

5、前后移动4;为修正电极，实为一废手锯片，电蚀不平时可折下重磨5；为摆轮调正对中器，装于上模扳并与之绝缘，可水平摆动和固定，旋动手轮带动一刀口片，推动摆轮轴颈以调节同轴度6；为电容插座，实为IC测试座，不同电容量组合均装夹干此，此种布置不同于常规，如将电器元件均装于电箱内通过电线引出，则因电容量少，电压低而放电回路长，电阻大,放电电流下降不陡，火花效率就差，所以一定要将电容尽量靠近电极，减少回路电阻很关键，否则必失败7；为上模扳升降旋纽，旋纽下部有刻度,分为100格，每格0.01mmB IjWiTi使用方法先将摆轮轴尖根部园弧处端面稍磨平,放置于平台上，由重力压块将摆轮轻压于平台注意要导电良好将

6、紫铜电极装夹于电极头，尽量调少旋转偏摆，电箱右上角选择旋纽置于（修极）位，电容量选0.47nF,电压选高,左下边开关打向上,将电极修正器置于适当位置并固定，打上电源开关，此时电极又旋又震，转动各旋纽，用反烤法烧蚀电极，当直径接近要求时，改用精规范，以提高电极表面不平度，可降低打孔时电极损耗见图三电极修正后关电源, 将电极升高, 不使影响调中工作, 移开电极修正器, 将摆轮调中器5 调到适当位并固定之 , 电箝右上角旋纽置于 （ 调中 ） 位 , 电压开关打向低端, 旁边开关置於中间位置, 调节旋纽 7 和摆轮调中器5 上白色手轮, 使刀口接近已断摆轴下凸台，电箱内通过分压器取得的2VDCS串入

7、蜂鸣器后加于刀口与轴颈之间，一边慢漫转动平台 2, 通过听声音确定摆轴对中与否,（ 见下图 ）对中后关电源, 移开调中器, 电箱右上角旋纽置於 （打孔 ）位置 , 电压开关扳向下方 （低）此时电压为40VDC,电容取0.022-0.22nF,频率取高点,规范取精,左下边第三个开关扳向下方 （ 铭牌有误 , 应为震动 ） 此时打孔电极只震动不旋转, 调节旋纽 7 使电极接近摆轴 , 开始打孔 , 可通过电压表指示协助进级, 无火花时指示最高, 当电压低于 25VDC时应停止进级, 到指针上升后再进级（ 图五 ）在修电极和打孔时应用毛笔粘媒油湿润火花处, 打孔直径大可用粗规范反之则取精规范 , 孔

8、深可由旋纽 7 之刻度读取, 由于电极也损耗, 实际深度约为刻度值0.6, 一般孔深为孔径 2.5-3 倍即可 由于有可重置的规范, 减少个人手艺因素, 免去磨钻头, 断钻头的麻烦, 加上无需退火 , 摆轮不会变形变色, 巳用十数次, 不失为较好的修复方法一点个人心得, 算是抛砖引玉a365打孔恒电根门中4口甲3出22CVAC3g欧1 rV口址域图 了做法雅如转前9.假欧电窸就电虢5 0做法附4Q0V,麻小金除调中电标电机®06 路图修电极时先用粗规准，40V,0.22-0.47 微法，精修电极时用30V,0.01-0.047 微法，打 孔时只用精规准，孔径大电容取大，反之取小.电容

9、器安装尽量靠近电极和工件处，以 减少放电回路的电阻！A Mini-EDM SystemOverviewI built a small EDM system, primarily for burning out broken-off taps in aluminum parts. But, now that I see how easily it works, I can see many other things that it could be used for. I built this whole system over a weekend, entirely out of parts

10、I had laying around. (I do have a lot of pieces, both electronic and mechanical.)ElectrodeThe electrode I made up consisted of a piece of .060 brazing wire soldered into the socket of an 8-32 socket-head cap screw. I threaded this into a nylon spacer that I happened to have, that already had an 8-32

11、 threaded hole in it. I put the spacer into the drill chuck on my mill. The nylon spacer is the insulator that prevents the electrode from grounding out to the chuck, and the rest of the milling machine. I connected the power supply to the electrode by way of a soft stranded wire, so that the wire w

12、ouldn't deflect the brazing rod. The end of the wire was stripped back about one inch, and the wire strands were loosely wrapped around the brazing rod. This made a remarkably good electrical contact, while allowing the brazing rod to turn freely. I could put just a slight bend in the rod so tha

13、t it would make a very slight (ie. .010") orbit if the spindle were rotated. This seemed to get the best metal removal and depth progress before the hole got filled with removed metal and shorted out.A view of the EDM electrode assembly in a Jacob's chuck.Power SupplyThe power supply I thre

14、w together was quite simple. A variac (variable autotransformer) is used to adjust output voltage. A 200 Watt variac (1-2 Amps at 110 V) is quite adequate. A step-down transformer, which provides isolation, is the next component. The one I used was center-tapped, allowing the use of 2 rectifiers. If

15、 your choice of transformer does not have the center tap, or the voltage is too low when using it, you could use a bridge rectifier on the two outer connections of the secondary to get higher voltage. A filter capacitor provides smoothing of the DC voltage produced. A resistor allows the electrode t

16、o short to the work without blowing fuses, and also moderates the flow of current from the raw DC supply to the EDM capacitor and electrode. Choose a resistance that will cause a short circuit current at least twice the desired EDM current at the selected voltage. Then, make sure the wattage is suff

17、icient to prevent the resistor burning up during a few seconds of short circuit. With the DC supply set to 30 Volts, a short would draw approximately 1 Amp, and since P=IAA2 * R, that is about 30 W, using a 30 Ohm Resistor. The ammeter shows current into the EDM capacitor. The EDM capacitor delivers

18、 short bursts of very high current whenever the insulating film of the EDM fluid gets very thin between the electrodeEDM FluidNot having distilled water around, I tried tapwater. It was boiled away very quickly by electrolysis, and didn't do much good even when it was there (perhaps all that bub

19、bling got in the way of the EDM process). I then tried the nearest thing at hand, which was "Alum-Tap", a light, clear tapping fluid for aluminum. It must be pretty close to EDM fluid, because it worked so well! It lasted a long time before being spattered away by the gases generated by th

20、e EDM action. Most of the time, I only had to add a few drops before the hole became filled with removed metal.OperationThe way I set this up was pretty much by trial and error. But, here are my settings: I set the power supply for 30 Volts. This seemed to give a very strong discharge action without

21、 producing too much gas or heat. I lowered the electrode with my NC control's jog buttons until I got electrode contact (indicated by about 1 Amp current suddenly appearing on the ammeter). I then raised the electrode with a very slow jog until the current dropped to zero. I then entered a manua

22、l command to advance the electrode at a rate of about .010" / minute, and after a few seconds, the ammeter would show a current of 1/4 to 1/2 amp. I would modulate the feedrate with the feedrate override controls, attempting to keep the current within these limits. By bending the electrode just

23、 a tiny bit, and running the mill's spindle at the slowest speed (80 RPM), I could get any diameter hole I wanted. I set it to just keep a tiny bit of the flank of the tap, but to burn out the entire web (central portion) of the tap. This allowed me to pick the remaining part of the tap's cu

24、tting edge out of the aluminum easily with a fine needle when the EDM electrode had cut all the way through. Progress all the way through was evident when the tool was still advancing with no EDM current.Since I didn't have a means of providing a flow of EDMfluid through such a small electrode,

25、I had to pull the electrode up every .025" or so, wipe out the contaminated fluid with a paper towel, and then drip a few drops of the Alum-Tap into the hole.电火花；穿孔机 '- - <.上海仪表广瀛二一 、<? .TJjH、,引曹一 |中 . . .当电器的插头插到电源插座里时，或者在工思里合试 断伸J刀时,在一刹那间，会看到一些火花发出。穹心观察一 在火花出垣的地方，例如嗣刀的末端和其他接触部分上，可看出

26、有毛刺剌凸出的金属瘤或表面上形成了凹穴。如果这应流电源情况下（如蓄电池或整流器等）所产生的火花，那4正极（或叫阳极）的一端上形成凹穴，接翼极（或叫阴极）的一上成为有凸出的金属瘤状。于是，电入花的作用使正极上的一部分金属移向负极.时又积集右极上这是被公就为电侵n境象在一般情龙下有害的，在开关、接触头等方面有捅坏作用，而应尽力免。可基，金属的电火花加工却正好利用效个电0小羽象来工的*辰内及.裁量旃将疝，以呼 财邛&篇的网小于J D x他通i，E巾代之WJ的 一跖;0.FK#山岚度人中，“生温皮昂舟（1°,欧 舞：i火.,jma沿山火也对叱极.也”用,ttrtitt 味鼎I明火化加

27、方” 力般的&属触博化、气化，fti分做判 二用的介取中；“W ”牙触化的命覆也因高温在液体中产蚀 侑川田皮曲佻刀入为收引”幺m于冷神向东充令明内的康内 在比火正加rw.阳极破电火改力金舄，一皎K人在人依的金丛为九甥此花也火花施工中，总卷以J：件 "加仁以，仆川大作信化中，出燃"棋件常和发）. 讨 *”也派肺叶枚电后，h件（照根，上就产生号工乂,阴ro 0版九J"编* 供网-注 lt 1： n z 匚处.» M怔L 2川发 M一定4/IM /斯麻X«<1£=蚀J 口 初於此 懦、K 80 个用呢的法性以第的，大及可分为拉动沙发门必m Y.让 网 年 渐甘思希FT"，或工件）以一怯解班及 定投例徒功 因 M 仔我掖动小，肝为两次机会使工A与工件问曲问原达 例蜜京的段他，而工JI及1：件的疑见则可用于前进静 仃动8 替法船利用自动器玲骞来便工典与工件间的用麻梆常保持 定 n中可能发生损为.你可求注避也的）。刖小而流市动也来 用5蛤城由劝到节法5的一种，它的工作危网