基于半斜环永磁体的永磁丝杠研究

Study on the LRMG based on semi-oblique ring permanent magnets

为解决永磁丝杠中螺旋磁极的制造难题,提出用半斜环磁极组合结构替代螺旋磁极的技术方案。应用有限元仿真技术,对永磁丝杠中的丝杠和螺母均采用螺旋磁极(G1)、分别采用螺旋磁极和斜环磁极(G2)、均采用半斜环磁极(G3)3种磁极结构方案的静特性进行了分析,从最大推力和最大转矩看,方案G2的数值略大于方案G1的50%,分别为G1数值的57.7%和53.9%,方案G3的数值则仅比方案G1的分别小4%和0.6%,证明了半斜环磁极组合结构方案与螺旋磁极的传动能力几乎相同。为了描述半斜环磁极极宽与节距的关系,提出了极距比的概念,并对极距比K=0~0.7时的半斜环组合磁极丝杠的静特性进行了仿真研究,结果表明,当K=0.3时,单位体积磁极产生的推力和转矩最大。为了提高磁能利用率,进行丝杠设计时应取K=0.3。

To solve the manufacture problem of helical-shape magnetic poles(HSMP)in linear-rotary magnetic gear(LRMG),a technical scheme of using semi-oblique ring magnetic poles(SORMP)to replace HSMP was proposed.The static characteristics of three schemes(both in screw and nut were HSMPs(G1),HSMPs in screw and ORMPs in nut(G2),and both in screw and nut were SORMP(G3))were simulated with FEM.According to the maximum thrust force and torque,G2 was slightly larger than the half of G1,which was 57.7%and 53.9%respectively,and G3 was only 4%and 0.6%smaller than G1.It was proved that the transmission characteristics of SORMP was almost same as HSMP.In order to describe the relationship of pole width and pitch of SORMP,a concept of pole pitch ratio(k)was proposed.The static characteristics of LRMG with SORMP were simulated for K=0~0.7,and it was found that when K=0.3,the thrust force and torque of unit volume pole had the largest value.To improve the pole utilization rate,it was suggested that K=0.3.