Thread processing method in trapezoidal lead screw processing

旋風銑削絲杠加工中螺紋與滾花一次完成工藝效率高，成本低，加工精度要求不太高的產品，其結構設計思路、方案有較好的推廣應用價值。

In the processing of whirlwind milling lead screw, the thread and knurling are completed at one time. The products with high process efficiency, low cost and low machining accuracy requirements have good popularization and application value.

旋風銑削法是一種效率高的螺紋加工方法，適用于批量較大的螺紋粗加工，其工藝是用硬質合金刀對螺紋進行高速銑削，它具有刀具冷卻好、生產效率高的優點。精度要求不高的螺紋，可用此法一次完成切削加工。旋風銑削刀的回轉軸線與工件軸線為空間位置關系，交叉角度為β角（等于螺旋升角）。其加工過程包括工件的旋轉運動，工件的螺旋軸向進給運動（或刀具進給），銑刀盤上刀刃的旋轉運動。

Whirlwind milling method is a high-efficiency thread processing method, which is suitable for rough machining of large quantities of threads. Its process is high-speed milling of threads with cemented carbide cutter. It has the advantages of good tool cooling and high production efficiency. For threads with low precision requirements, this method can be used to complete cutting at one time. The rotation axis of the cyclone milling cutter and the workpiece axis are in spatial position relationship, and the intersection angle is β Angle (equal to spiral rise angle). The machining process includes the rotary motion of the workpiece, the helical axial feed motion of the workpiece (or tool feed), and the rotary motion of the blade on the milling cutter head.

1 零件加工要求

1. Part processing requirements

零件為活動扳手調節開口寬度的螺輪，材料為20號圓鋼，牙側有一定粗糙度要求，切斷處螺牙部需要倒角，中間銷孔與外圓柱面有較好的同軸度，否則調整時不會靈活自如，甚卡死，為便于大拇指握持撥動，其表面要有平行于軸心線的直紋滾花。

The part is a screw wheel with adjustable wrench to adjust the opening width. The material is No. 20 round steel. There are certain roughness requirements on the tooth side. The screw tooth at the cutting part needs chamfering, and the middle pin hole has good coaxiality with the outer cylindrical surface, otherwise it will not be flexible or even stuck during adjustment. In order to facilitate the thumb to hold and move, its surface should have straight knurling parallel to the axis line.

2 梯形絲杠加工工藝的分析與比較

Analysis and comparison of processing technology of trapezoidal lead screw

絲杠加工原來采用車削加工，工藝路線為:冷拔→滾花→車螺紋→校正→鉆孔→切斷→倒角，不僅效率低、成本高，且由于小圓鋼剛度低，車削、滾花時易變形，小號螺輪不能生產，為此我們設計了旋風銑削絲杠設備，不僅將轉速由經驗認定的1000r/min左右提升2000r/min以上而且將銑絲滾花一次完成。 其工藝路線變為:冷拔→滾花、銑絲→校正→鉆孔、切斷→倒角。雖然旋風銑削使小徑工件有較大變形（大徑件變形較小），但校正也容易。改進后的工藝具有如下特點:

The lead screw was originally processed by turning. The process route is: cold drawing → knurling → thread turning → correction → drilling → cutting → chamfering. It is not only low efficiency and high cost, but also due to the low stiffness of small round steel, it is easy to deform during turning and knurling, and the small screw wheel can not be produced. Therefore, we designed a cyclone milling lead screw equipment, which not only increased the rotating speed from about 1000r / min determined by experience to more than 2000r / min, but also completed the milling and knurling at one time. Turn it into milling and chamfering → turn it into cold drawing and chamfering → correct it. Although cyclone milling causes large deformation of small-diameter workpiece (small deformation of large-diameter workpiece), it is also easy to correct. The improved process has the following characteristics: