【正文】 successful application of the entire manufacturing has greatly promoted the rapid development of the mold industry. In recent years, China has made great progress in the mold industry, new materials, new technology and advanced processing equipment. Mold parts standardization, specialization and mercialization have reached a higher level. The content of this paper is to design the injection mold for a toothpaste cap. The material is polyethylene plastic (PE). According to the shape characteristics of toothpaste cap structure and the existing injection molding process, the use of gear and rack as the screwseparating mechanism, this paper designs an efficient spin injection mold with autooff thread. Unscrewing institutions include spur gears, the rack, straight bevel gears and the screw core. To achieve rapid forming of plastic parts and mold opening, a point gate and secondary mold opening structure of threeplate molds are used. This paper briefly describes the injection mold, the autooff thread process and principles of mold design. Unscrewing of the gear and rack driving system for the mold design and the main parts of the plastic injection mold are calculated, and the actual production of economic rationality is also considered in the design process. Key Words： Injection mold； Internal thread； Point gate； Gear rack mechanism 牙膏瓶蓋注塑模具設(shè)計(jì) III 目 錄 摘 要 ..................................................................................................................................... I Abstract ...................................................................................................................................... II 引 言 .................................................................................................................................... 1 1 塑料模具及塑料模具行業(yè) .................................................................................................. 3 塑料模具簡介 ........................................................................................................... 3 塑料模具行業(yè)的現(xiàn)狀及發(fā)展方向 ........................................................................... 3 2 注塑成型工藝與設(shè)備 .......................................................................................................... 7 注塑模的組成及各部分作用 ................................................................................... 7 注塑成型過程 ........................................................................................................... 7 注塑機(jī) ....................................................................................................................... 9 3 模具分析與設(shè)計(jì) ................................................................................................................ 11 設(shè)計(jì)任務(wù)要求 ......................................................................................................... 11 塑件介紹及塑件材料 ............................................................................................. 12 塑件介紹 ...................................................................................................... 12 塑件材料分析介紹 ...................................................................................... 12 分型面選擇 ............................................................................................................. 13 型腔布置方案 ......................................................................................................... 14 注塑機(jī)的選擇 ......................................................................................................... 15 澆注系統(tǒng)的設(shè)計(jì) ..................................................................................................... 15 主流道的設(shè)計(jì) .............................................................................................. 16 定位環(huán)的設(shè)計(jì) .............................................................................................. 17 分流道設(shè)計(jì) .................................................................................................. 18 澆口的設(shè)計(jì) .................................................................................................. 18 導(dǎo)向機(jī)構(gòu)的設(shè)計(jì) ..................................................................................................... 19 脫 螺紋機(jī)構(gòu)設(shè)計(jì) ..................................................................................................... 20 脫螺紋機(jī)構(gòu)種類 .......................................................................................... 20 旋轉(zhuǎn)自動脫螺紋機(jī)構(gòu) .................................................................................. 20 澆注冷卻系統(tǒng)的設(shè)計(jì) ............................................................................................. 22 模架的選擇 ........................................................................................................... 23 4 模具零件的設(shè)計(jì)計(jì)算 ........................................................................................................ 24 齒輪齒條傳動系統(tǒng)的設(shè)計(jì)計(jì)算 ............................................................................... 24 牙膏瓶蓋注塑模具設(shè)計(jì) IV 定模板尺寸的設(shè)計(jì)計(jì)算 ........................................................................................... 25 動模板的尺寸的設(shè)計(jì)計(jì)算 ....................................................................................... 27 流動比的校核 ........................................................................................................... 28 注塑機(jī)的校核 ........................................................................................................... 28 成型零件工作尺寸的確定 ....................................................................................... 29 5 經(jīng)濟(jì)性分析 ........................................................................................................................ 32 結(jié) 論 .................................................................................................................................. 33 參 考