不等螺旋角立铣刀的抗振性及设计研究

Study on Vibration-Resist Mechanism and Design of Variable Helix End Mill

分析传统立铣刀工作时产生振动的原因,提出不等螺旋角立铣刀抗振原理。根据其结构特点,推导出不等螺旋角立铣刀在圆周方向上等分隔处的刃长的计算公式。通过瓦尔特机床公司tool-studio加工软件模拟铣刀的槽形截面图,验证了公式的正确性,并举例论述公式的应用。根据公式分析了立铣刀各刃等分隔的影响因素,并得出铣刀的直径、螺旋角和齿间夹角对立铣刀刃长的影响最大,从而提出不等螺旋角立铣刀结构设计的思路。为了验证不等螺旋角立铣刀抗振性,进行拐角铣削和侧铣对比切削试验,结果表明:与传统立铣刀相比,不等螺旋角立铣刀具有抑制振动和提高工件表面粗糙度的优点。

Analyzing vibration of traditional end mill in working,this paper presents vibration-resist mechanism of variable helix end mill. As the structural characteristic,formulas to calculate the length of cutting edges intervals between each other of the variable helix end mill in a peripheral direction are deduced. The formulas are proved by the flutes in cross-sections perpendicular to the axis. The application of the formulas is explained. According to the formulas,the factors influencing intervals between each cutting edge are analyzed. Furthermore,the effect of end mill the diameter,helix angles and pitch angles. The design method for variable helix end mill is advanced. In order to prove vibration-resist of variable helix end mill,cutting comparative experiment of corner and plane milling is done. The experimental results show that variable helix end mill compared with conventional end mill can be applied to determine vibration and improve surface roughness of the workpieces.