外形非轴对称注塑件螺纹起始点一致性定位或规定角度转动实现方法

对相配合的两件带螺纹且外形均为非轴对称的注塑件(如瓶盖和瓶体)分别进行了模具设计,在瓶盖注塑模具设计中,采用了可编程序控制器(PLC)作为主要的控制螺纹起始点位置的机电部件,采用光电传感器作为辅助部件,通过PLC的累加程序和输出电路,将PLC接入注塑机的液压顶出控制电路中,从而实现了瓶盖螺纹型芯在每次注塑完成后其螺纹起始点位置均保持一致的目的;在瓶体注塑模具设计中,通过对瓶盖模具PLC程序的改变,实现了瓶体螺纹型芯在每次注塑完成后其螺纹起始点转动一个规定角度的目的。通过以上设计,使得瓶盖和瓶体在装配后实现了规定的多样性特殊装配外观效果。     

型芯内缩式自动脱螺纹注塑模设计

根据带断续内螺纹塑件的特点，设计了型芯内缩式自动脱螺纹注塑模。模具型芯由2个型芯组件和1个双斜面楔块组合而成，通过楔块与型芯组件的相对运动，使2个型芯组件内移，实现自动脱螺纹。该模具适用于带断续内螺纹的塑件或内壁有环形断续凹槽的塑件。     

收缩型芯内抽芯和旋转型芯脱螺纹注塑模

根据放大镜框的结构特点,设计了镜框注塑模。论述了放大境框注塑模结构和工作原理。该模具一模两腔,矩形截面侧浇口进浇,收缩型芯内抽芯和旋转型芯脱螺纹。成型塑件孔壁环形凹槽的型芯由6个大扇瓣块和6个小扇瓣块组合而成,通过大、小扇瓣块相对运动,使12个扇瓣块径向内移,实现环形凹槽抽芯。同时利用开模力,通过齿轮-齿条传动,使横向型芯旋转脱螺纹。     

注塑模伺服同步自动脱螺纹技术的改进

以在注塑模中含有螺纹塑料零件自动脱螺纹为目标,设计和改进了伺服同步自动脱螺纹机构,该机构使用伺服电机的转动带动推板推出注塑件,在机构中增加了一个棘轮系统,伺服电机反转圈数超过正转,通过棘轮打滑使得推板回程位置准确,使用步进电机带动螺纹型芯脱出螺纹.经过修改和优化的两个系统之间同步的PLC控制可以更好的适合实际注塑情况,...     

自动脱螺纹注塑模设计

给出了链轮传动自动脱螺纹注塑模结构。该模具采用热流道针阀式点浇口进料,无流道废料;通过链条传动使螺纹型芯转动,同时利用端面止转,实现自动脱螺纹;在动、定模型腔及螺纹型芯上分别设置三套冷却系统,使模具充分冷却。模具结构紧凑、工作可靠、操作方便、运转平稳、冷却效果好、劳动强度低、生产效率高,生产的塑料件精度高。     

三板式型芯转动脱螺纹支架注塑模

论述了齿轮-齿条传动型芯旋转脱螺纹支架注塑模的结构特点和工作原理。该模具一模两腔,二次分型,点浇口进料,利用开模力,通过齿轮-齿条传动,使型芯旋转脱螺纹,采用导板-滚轮机构实现侧抽芯。模具工作可靠,操作方便,生产效率高,塑件精度高。     

圆形盲孔注塑模纠偏机构

圆形盲孔注塑模纠偏机构,有模板,模板连接推料板和芯子套,推料板和芯子套连接滑块,滑块与型模相连,在芯子套和型模中安装型芯,其型芯与芯子套中间制有活动调节面,在芯子套中制有定位调节孔,定位调节孔中安有调节件,调节件头部与型芯相配合。本实用新型以调节孔中的调节件对型芯调节,使型芯经活动调节面摆动,达到调正、纠偏,具有方便、省力、效果好的特点(专利号 ZL 00201652.4)。 RP-04摘自《实用新型专利公报》第16卷第44号P6 (XS-01) 圆形盲孔注塑模纠偏机构…     

齿轮-齿条传动横向型芯旋转脱螺纹注塑模

论述了齿轮-齿条传动横向型芯旋转脱螺纹注塑模结构特点和工作原理。该模具一模两腔,潜伏式浇口。利用开模力,通过齿轮-齿条传动,使横向型芯旋转脱螺纹。齿条设置在注射机型板之外,因此齿条长度不受模具厚度的限制,简化了模具结构,减小了模具体积。模具结构紧凑,工作可靠,操作方便,生产效率高,生产的塑件精度高。     

笔尖注塑模螺纹脱模机构的优化设计

根据笔尖结构为锥形并需要内螺纹脱模的特点,分析和比较了目前模具采用的自动脱螺纹机构。对笔尖内螺纹部分设计三段轴向开槽,优化笔尖结构,设计了二次推出不带旋转机构的自动脱螺纹注塑模。型芯部分由1个型芯和1个三角套组合而成,通过三角套与型芯组件的相对运动,使三角套内缩以实现自动脱螺纹。同时采用二次推出机构完成整个注塑件的脱模,由于模具脱模部分不需要设置旋转机构,简化了模具结构,缩短了开模时间。     

中心推杆直接推件包装筒注塑模

介绍了塑料包装筒注塑模的结构,论述了模具结构特点和工作原理。该模具采用直接浇口进料,由哈夫块及哈夫块上的螺纹镶件成型制件外形和螺纹,燕尾导条哈夫分型。型芯中心装有推杆,推杆设有气槽,保证塑料熔体正常快速充模,避免制件与型芯之间出现真空导致推出困难。采用中心推杆直接推出制件,使模具厚度减小40%。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。