对称反向斜齿轮塑件成型工艺分析与注射模具设计

基于对一种对称反向斜齿轮塑件的结构特性及注射成型工艺的分析,完成了该塑件注射成型模具总装结构的创新设计。成型零件结构上,采用两部分斜齿轮型腔分别成型两段旋向相反的斜齿轮;脱模方式上,借助向心推力轴承使斜齿轮型腔"旋转",采用弹簧限位拉杆、倒锥形拉料杆和限位拉板四次顺序定距分型结构来实现浇注系统凝料和塑件的自动脱模,有效解决了两部分斜齿轮型腔镶块旋转方向相反而导致的干扰问题。同时采用定位镶块对两部分斜齿轮型腔镶块进行复位定位,有效解决了旋向相反的两段斜齿齿槽合模对拼时的位置对正问题。

Analysis on Molding Process and Design of Injection Mould for Symmetric Reverse Plastic Double-Helical Gear

Based on the analysis of structural characteristics and injection molding process of symmetric reverse plastic double-helical gear part,the innovative design of the assembly structure of the injection mould was completed. As to the molding parts structure,two-part reversed helical gear is respectively formed by two helical gear cavities. In the demolding mode,the helical gear cavity is"rotated"by means of the radial thrust bearing,and the four-stage sequential fixed-distance parting mechanism of spring-limiting rod,the inverted conical puller rod and the limit puller plate are used to achieve the automatic stripping of feed system condensate and plastic part,which effectively solves the interference problem caused by the opposite direction of the two parts of helical gear cavity insert blocks rotating. Meanwhile,using positioning insert blocks to reset the position of the two parts of helical gear cavity insert blocks effectively solves the problem of position alignment when the two diagonal helical teeth of the rotating direction are assembled opposite to each other.