摘要
针对螺杆泵关键部件螺杆转子设计过程复杂、加工难度高导致啮合间隙不均匀的问题,在分析螺杆啮合间隙形成机理基础上,运用空间解析几何基础理论,提出基于啮合间隙的螺杆齿形设计新方法,建立螺杆加工过程进刀轨迹-螺杆齿形-啮合间隙转换方程;结合微分几何等距曲面构型原理,得到预定加工间隙的螺杆端面齿形;研究螺杆与刀具在加工过程中的空间包络特性与几何特性,结合机床、螺杆、刀具协同运动所生成的接触线形状和空间位置参数,提出一种基于离散点齿形的螺杆加工成形刀具设计方法——形位几何法,该方法基于具有稳定接触的包络结构,将抽象的空间包络问题转化为平面解析几何问题,简化包络求解模型,克服传统啮合理论设计刀具时无法精确计算齿形曲线尖点的关键性技术难点,提高成形刀具齿形设计的精确性。
Screw pump product often exhibits low volumetric efficiency and low service life due to the complicated screw rotor design,manufacturing and the non-uniform clearance.On the basis of analyzing the formation mechanism of screw clearance,a new design method of screw tooth profile based on the given clearance is proposed by using the analytic geometry theory in three dimensions.The transformation equations related to the feed path,screw tooth profile and the clearance in screw manufacturing process are then established.In combination with the isometric surface configuration of differential geometry,the screw cross tooth profile with the predetermined clearance is obtained.Furthermore,after investigating the spatial enveloping characteristics and geometry characteristics between screw and cutter in manufacturing process,as well as the shape and spatial position parameters of contact lines ~sulting from the movement for three combinations of machine tool,screw and cutter,a novel design method of forming cutter-shaped-position method is proposed,which is based on the discrete points for tooth profiles of screw manufacturing forming cutter.The method simplifies the solving model by virtue of converting the abstract spatial envelop into plane analytic geometry.It is shown to solve the problem that traditional meshing theory for cutter designing can not accurately calculate the cusp of tooth profile curves,and it therefore improves the tooth profile accuracy of forming cutter.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2014年第9期48-57,共10页
Journal of Mechanical Engineering
基金
国家自然科学基金(51175522)
重庆市科技攻关(csts2012gg-yyjs70011)
重庆市自然科学基金重点(csts2013jjB70002)资助项目
关键词
螺杆泵
容积效率
间隙
成形刀具
screw pump
volumetric efficiency
clearance
forming cutter