Development of a micro screw, a micro nut and a micro gear utilized extra fine wires

本研究开发了一种利用超细线材制造微机械零件的新方法，生产了微机械系统的微螺杆、微螺母和微齿轮等微机械零件。该制造方法可以研制出设备小、工艺简单、不需要昂贵设备的三维微机械零件。微螺杆的制作方法如下：制作了直径为0.7毫米的镀金针针。将直径同为20微米的涂有金的铜线和涂有锡的钨丝缠绕在针脚上，彼此不开孔。盘绕的针脚是焊接的。把钨丝从焊针上剥下来。铜线像螺纹一样绕在针上。制作出螺距为40微米的微螺杆。微螺母的制作方法如下。制作了直径为0.715毫米的无金镀针。将直径为20微米的铜丝和钨丝分别缠绕在针脚上，彼此不开孔。所述盘绕的针插在开针的头孔中。将熔化的热焊料倒入盘绕针件与开针头孔之间的空隙中。将针脚拔出，将钨丝从中心窄孔中剥落。生产出螺距为40微米的微型螺母。外微齿轮和内微齿轮采用相同的工艺，由线圈、钎焊线和剥离线组成。外/内微齿轮有18/20个齿，模数为18.1/32.5微米。

In this research, a novel manufacturing method for the micro mechanical parts utilized extra fine wires was developed, and several micro mechanical parts like a micro screw, a micro nut and a micro gear for micro mechanical systems were produced. The manufacturing method can develop three dimensional micro mechanical parts with small facilities and with simple process and without expensive equipments.The micro screw is made as follows. A needle pin plated with gold, which diameter is 0.7 millimeter, is prepared. A pair of a brass wire coated with gold and a tungsten wire coated with tin, which diameters are same of 20 micrometers, is coiled around the needle pin without an opening each other. The coiled needle pin is soldered. The tungsten wire is peeled from the soldered needle pin. The brass wire remains around the needle pin as a screw thread. The micro screw with pitch of 40 micrometers is produced.A micro nut is made as follows. A needle pin plated without gold, which diameter is 0.715 millimeters, is prepared. A pair of the brass wire and the tungsten wire, which diameter are same of 20 micrometers, is coiled around the needle pin without an opening each other. The coiled needle pin is inserted in a head hole of a split pin. Melted hot solder is poured into gap between the coiled needle part and the head hole of the split pin. The needle pin is drawn out, and the tungsten wire is peeled through the center narrow hole. The micro nut with pitch of 40 micrometers is produced.An outer micro gear and an internal micro gear is made by same processes consist of coiling wires, brazing wires, and peeling wires. The outer/internal micro gears have 18/20 teeth with module of 18.1/32.5 micrometers.