木材高速螺旋式玉米铣刀的设计与优化

Design and Optimization of a High-speed Helical Corn-shaped Milling Cutter for Wood

使用砂光机磨削木材存在功耗大、噪声大和粉尘多等问题，因此设计了一种木材高速螺旋式玉米铣刀，其采用“以切代磨”的方式使这一问题得到解决。该玉米铣刀形似“玉米”，刀尖处直径Ф160～240mm，可实现高线速度切削，刀身均布有2～6排螺旋式阶梯槽，各螺旋槽上均布有6～10个刀片槽，可实现刀片逐刃切削；刀具采用组合结构，刀片前角20°～26°、后角9°～13°，刀具下装有可调高的碟形弹簧，以实现刀片磨损后的补偿，提高刀具材料利用率。通过分析计算发现，初步设计的玉米铣刀质量达105kg，刀身和刀片安全系数在83～402之间，材料浪费严重，因此在优化设计时刀身内部采用了中空结构以减轻质量，装有配重拉杆以调整平衡，增加刀片数量，优化后玉米铣刀质量降至43.5kg，安全系数降到33～70之间，完全满足强度要求。

Grinding of wood with grinding equipment can cause such problems of large power consumption, loud noise and lots of dust. A high-speed helical corn-shaped milling cutter for wood is designed to solve the problems above by means of“cutting instead of grinding”. The milling cutter is like a“corn”, with the diameter of the cutter point between 160-240mm, able to realize high linear speed cutting, with 2-6 rows of spiral grooves evenly distributed on the cutter body, 6-10 blade groves evenly distributed in each spiral groove to realize each edge’s cutting. The combination structure is adopted fro the cutter, with the front angle of a blade ranging from 20 degrees to 26 degrees and the rear angle of the blade from 9 degrees to 13 degrees. A disc-shaped spring is installed under the cutter to realize compensation for abrasion of the cutter and improve the utilization rate of cutter material. It is found out through calculation and analysis, the preliminarily designed corn-shaped cutter has mass of up to 105kg, with the safety coefficients of the cutter body and cutter blades between 83 and 402, indicating a severe waste. Therefore, in the optimal design, the hollow structure is adopted inside the cutter body to reduce its mass, with a counter weight lever provided to adjust balance and the number of blades increased, reducing the mass of the corn-shaped cutter to 43.5kg and the safety coefficient to 33-75, satisfying the requirements for strength.