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密 級:
畢業(yè)設計附件
外文及翻譯
學生姓名
學院名稱
專業(yè)名稱
機械設計制造及其自動化
指導教師
年
5月
18日
新一代注塑技術(shù)
外文出處 University Hospital Zurich, Zurich, Switzerland
摘要:本文介紹新一代瓶坯注塑技術(shù)的特點以及通過一個循環(huán)所實現(xiàn)的瓶性能。這一循環(huán)使瓶胚冷卻不再需要機械手和引出板,而是瓶胚直接在模芯上冷卻,在進一步通過2.5 注射循環(huán)冷卻之后被頂出。這使制件的冷卻得以改進,從而大大提高了每個陰模的產(chǎn)量。從工作單元去掉機械手減少了空間需求,并大大簡化了系統(tǒng)。
關(guān)鍵詞: 注塑模具設計 循環(huán)速度
1、概述
轉(zhuǎn)位瓶胚注塑技術(shù)是在Husky 注塑系統(tǒng)雙壓板機器設計發(fā)展起來的。該系統(tǒng)有一個四面動壓板繞橫軸旋轉(zhuǎn)。每一面配一個典型的半冷塑模。原模系統(tǒng)是一個48 陰模,從而提供192 個模芯。定壓板上裝有一個標準的熱流道和半陰模。 本系統(tǒng)配備一個標準兩級注塑裝置,該裝置有一個120 毫米擠塑機和120 毫米注射壓料塞,注射壓料塞上有一個機筒頭和分配閥連接兩級。用目前的瓶胚設計,目標重量是47.3 克瓶胚,從而注射量為2270 克。兩42 個不同的聚對苯二甲酸乙二醇酯螺桿用于本系統(tǒng),每個都取得了可以接受的效果。 當機器循環(huán)時,塑料首先注射到A 面。由于瓶胚要留在模芯上,瓶胚在開模不需要象在傳統(tǒng)系統(tǒng)上那么硬。因此,循環(huán)的絕大部分冷卻可以在隨后的機器循環(huán)期間從閉模轉(zhuǎn)到在模芯上冷卻。然后循環(huán)需要一個非常短的冷卻期間以允許模具釋壓,注射和保壓也是如此。當開模時,這一面轉(zhuǎn)位到壓板的頂部表面,然后塑料在B 面注射。當D 面到達前端時,此時A 面在壓板的底部位置,頂桿在這里被啟動,瓶胚被從機器卸到制件引出傳送器上。注射行程對循環(huán)時間沒有影響,因而可以較慢地完成。重力幫助確保制件脫離模具落下。制件落在其格端頭的傳送器上,造成表面擦傷的可能性較小。 在頂部、背部和底部位置,氣沖成型系統(tǒng)對瓶胚提供表面冷卻。由于瓶胚保持在模具的模芯上,它們還容易在內(nèi)表面得到傳導冷卻??傮w上講,瓶胚的整體溫度比它在傳統(tǒng)模塑系統(tǒng)和冷卻引出板中呆類似的時間要冷。
2、瓶性能
我們分析轉(zhuǎn)位系統(tǒng)的一個重要方面是拿這種系統(tǒng)生產(chǎn)的瓶胚制造出來的瓶的性能與傳統(tǒng)工作單元上生產(chǎn)的類似瓶胚制造出來的瓶相比較。表1 給出從進行的試驗中得出的比較數(shù)據(jù)。 轉(zhuǎn)位瓶胚的性能在強度測試中一直較好,這是因為改進的澆口質(zhì)量允許材料在瓶內(nèi)較好地分布,沒有跡象表明使用這種系統(tǒng)在瓶的任何地方結(jié)晶度升高。生產(chǎn)的轉(zhuǎn)位樣品可能平均較輕,因為它們的重量分布要緊密得多。
3、系統(tǒng)的特點
這種托坯最明顯的好處是需要的模內(nèi)冷卻時間減少了,從而減少了整個循環(huán)的時間長度。目前,這種系統(tǒng)用最大壁厚為4 毫米的47.3 克瓶胚工作。這種瓶胚加工循環(huán)時間測定為22.5 秒,對于一個陰模系統(tǒng)來說是最佳的了。轉(zhuǎn)位48 陰模系統(tǒng)實現(xiàn)14.2 秒的循環(huán),能取得較好的商業(yè)質(zhì)量結(jié)果。圖2 給出循環(huán)細分的比較情況。
旋轉(zhuǎn)塔臺不再需要機械手。這樣,就減少了由傳統(tǒng)系統(tǒng)上機械手故障造成的干擾告警和服務停機時間。制件頂出現(xiàn)在不是機械循環(huán)時間的一個因素。隨著消除機械手需要的開模間隙減少了,隨著模具行程的減少還提高了空循環(huán)速度。
系統(tǒng)的另一個好處是需要的地板面積減少,以及由于沒有機械手和引出板冷卻系統(tǒng),系統(tǒng)的可靠性得以提高的潛力。預計不發(fā)生機械手故障的整個系統(tǒng)可靠性可允許系統(tǒng)可用性提高30%。轉(zhuǎn)位系統(tǒng)的地板面積只有傳統(tǒng)48 陰模系統(tǒng)所需面積的55%。與之相伴的還有每英尺地板面積的產(chǎn)量進一步提高。
使用轉(zhuǎn)位系統(tǒng)使瓶胚的澆口質(zhì)量得到改進。在閥澆口區(qū)冷凍之后,瓶胚在較短時間內(nèi)與閥桿的熱點接觸,因為瓶胚在陰模內(nèi)的冷卻時間被大大減少。去掉這一熱源就消除一個結(jié)晶源。除了較好的視覺效果,還導致澆口區(qū)更結(jié)實,從而使得整個瓶側(cè)壁區(qū)更好,及有更多的機會減輕基礎(chǔ)區(qū)瓶胚的重量。
瓶胚留在模芯較長時間。與標準瓶胚注塑系統(tǒng)相比,整個瓶胚冷卻得到改進。在一個傳統(tǒng)的機械手冷卻板內(nèi),制件遇到被冷卻的管表面就會收縮,這樣熱傳遞就不完美。在轉(zhuǎn)位系統(tǒng)中,制作在模芯上收縮,從而保持熱傳遞,在被頂出時,轉(zhuǎn)位瓶胚的全面整體溫度比瓶胚從傳統(tǒng)系統(tǒng)的引出位置取出時要低。還有,對于目前的瓶胚設計來說,不向頸模圈區(qū)供應冷卻水,在頂出時仍比標準系統(tǒng)要冷得多。對于一個典型的成型系統(tǒng)來說,冷卻該區(qū)能限制循環(huán)。
轉(zhuǎn)位系統(tǒng)用幾種不同材料及測試的兩種不同材料和兩種不同的聚對苯二甲酸乙二醇酯螺桿設計,可以看到乙醛(AA)量一直較低。與注射量相比這一循環(huán)時間對注射裝置提出非常高的要求,注射裝置連續(xù)不斷地沖刷沒有一點滯留時間的螺桿。
由于模具內(nèi)的峰值陰模與兩個不同的螺桿相符,并與不同的加工設置一致,乙醛量到底有多低主要原因在于模具集料管。用目前的模具可以看到的第二個好處是有非常好的重量分布,從而允許在目前制件規(guī)格的允差內(nèi)把整個制件的重量降到最低程度。
4、介紹IKB-MOULD設計的基礎(chǔ)
注塑模組成的分析處理分為兩部份:
設計的首字母和詳細的設計,初期的設計決定模具的組成,例如模具類型、型腔數(shù)、流道的類型、澆口類型等。詳細設計是型芯型腔的組成、澆注系統(tǒng)的設計、冷卻和排氣系統(tǒng)的設計、集成分析和最后的草圖。他們需要什么,分析什么是好的CAIMDS的發(fā)展方向。
他們所擁有的客戶對產(chǎn)品的要求。包括產(chǎn)品外形和詳細的尺寸。
一個已經(jīng)設計好的模具方案這個方案包括模具設計的初級部分和標準部分舉例來說模具設計的基礎(chǔ)動模和定模的一部分填充和頂出的一部分。注塑模具設計的行業(yè)知識等。
設計者從專業(yè)知識中得出模具設計的設計計劃和詳細步驟這些知識包括原材料的選擇型腔型芯分型面的規(guī)劃和其他相關(guān)細節(jié)的介紹。
他們所想要得一個先進的交互式模具設計環(huán)境。模具設計是由一系列細小的環(huán)節(jié)組成的設計程序。這些程序通常需要將已有的模塊和制作好的模件裝配好。這些模具設計系統(tǒng)不需要自動完成尤其是對切口部分特征比較復雜的產(chǎn)品。先進的交互式程序善于整合自動化運算法則和有經(jīng)驗的設計者的在線知識交流。
標準件/早期設計部分/組裝/產(chǎn)品管理。一個注塑模具在其它注塑模里相同的形狀尺寸分別有型腔型芯。這些部分與注塑模產(chǎn)品無關(guān)。他們使用在不同模具中重復使用的大概標準。
有用的工具包括實體設計和分析計算在模具型腔型芯中的設計。型芯和型腔的外形和大小直接影響模具產(chǎn)品。這些部分也是模具設計中相當重要的環(huán)節(jié)。他們的幾何形狀要求可能相當苛刻。因此一些模芯設計工具的發(fā)展方向基于自動生成模具型芯交互作用是相當有用的。
組裝設計在傳統(tǒng)的CAD/CAM設計系統(tǒng)中模具的實體形狀被當作幾何圖形儲存模型在一個三維空間以邊和面的形式生成。象這樣的一個以嚴密的幾何計算表現(xiàn)的視覺外形可以完成工程分析和模擬。但是這種工作方式不適合設計高層數(shù)據(jù)和產(chǎn) 品的幾何實體外形的關(guān)系。
模具設計者更喜歡裝配環(huán)境的設計而不是一種簡單的固體模型環(huán)境。這個方案被 Ye et al 提出。
5、循環(huán)速度的限制因素
在整個循環(huán)期間對轉(zhuǎn)位循環(huán)的影響因素可以分為五個組成部分: (1)機器空循環(huán)時間(這是完成開模、旋轉(zhuǎn)塔臺90 度,閉模和為注射做準備的循環(huán)的時間); (2)陰模充料時間; (3)為避免正冷卻的制件形成凹陷的保壓要求; (4)模內(nèi)冷卻以使模具從保壓期間要求的合模力噸數(shù)中釋壓; (5)在頂出時瓶胚的大量熱造成的表面熱以及熱再生,以避免后續(xù)處理期間制件被刮傷或有粘性。 系統(tǒng)的機器空循環(huán)時間被優(yōu)化。模具不必開那么多,以允許轉(zhuǎn)位旋轉(zhuǎn),象傳統(tǒng)系統(tǒng)為允許機械手進入模具區(qū)所要求的那樣,從而減少了開模和閉模時間。轉(zhuǎn)位速度也比機械手進去,轉(zhuǎn)移制件和機械手再出去快。目前4.3秒的機器空循環(huán)已經(jīng)充分優(yōu)化,改進的余地很小。 如果注射裝置尺寸過小,生成熔體可能是一個限制因素。已經(jīng)在循環(huán)速度低達11.6 秒,用2280 克注射量的0.82IV 樹脂測試過目前120 毫米的螺桿可接受的塑煉能力。這時沒有剩余的滯留時間,這樣循環(huán)將受螺桿性能限制。 充料和保壓時間大約為9 秒。現(xiàn)正在做試驗以量化最佳的充料速度和保壓外形。 冷卻0.5 秒可以實現(xiàn)模具釋壓,但目前的工藝需要冷卻1.3 秒,循環(huán)目前受到在制件上形成凹陷限制。這受到包裝數(shù)量、保壓壓力和開模的速度的影響。由于轉(zhuǎn)位循環(huán)的冷卻時間非常短,瓶胚遇到陰模壁收縮的時間非常少。正在研究改進這方面的循環(huán)性能的機會。 目前出模時的瓶胚溫度將允許循環(huán)時間遠遠少于13 秒,如果僅這一方面是循環(huán)的限制因素的話。
6、瓶胚設計的考慮因素
根據(jù)最初比較原型系統(tǒng)中使用的瓶胚以及為促進使用轉(zhuǎn)位方法減少轉(zhuǎn)位循環(huán)而對各種瓶胚設計做的試驗。因此,實施一種轉(zhuǎn)位系統(tǒng)而非較傳統(tǒng)的成型方法的決定是由于其他許多考慮因素)轉(zhuǎn)位系統(tǒng)要求四套制件模芯,這樣模芯的復雜性以及由此導致的整個模具成本是選擇的一個因素。其他因素包括生產(chǎn)能力要求、可用的地板面積、資本成本。
The Fresh Generation Injection Mould Technique
Abstract : The original is introduced fresh generation vase earthen brick mould plastics technique distinguishing feature along with by means of the vase performance that the cycle was achieved .That this cycles causes an a jar of embryo become cool not needing manipulator and the lead-out plank again , but is an a jar of embryo directly is living that the standard becomes cool on the rush pith , and is living further by means of 2.5 to inject after the cycle cooling being come out by the peak .This causes the finished piece cooling may improve , thereby lift every one the overcast standard yield enormously .Decreased the demand in room through the work cell gets rid of the manipulator , and simplify the system enormously .
Keyword : Injection mould design Cycle velocity
1、Summary
The indexing vase embryo mould plastics technique is designed the development at twin teeterboard machinerys of Husky's mould plastics system .Ought to systematically there be an all sides to stir the teeterboard to coil the cross axle to circle .Each one section is matched somebody with somebody a type semi to cool to mold the standard .
The master stamper systematically is 48 an overcast standard , thereby supplys 192 standard rushs pith .Fiing teeterboard jacket possess criterion heat flux a road and semi an overcast standard .Standardized two steps of moulds plastics units are equipd to this system , and that unit possessone 120 millimeters to pack the engine molding and 120 millimeters to inject the pressure stuff to squeeze in , and injecting along the Great Wall the pressure stuff possess engine a thick tube-shaped head and a distribution valve to join two grades .Designing in the way of the vase embryo at the moment , target weight is the 47.3 grams vase embryos , thereby injecting amount is 2270 grams .Two 42 differences is gatherd being used a system to the benzol two methanoic acid glycol ester studs , and every one wholly acquireed the effect that may be receiveed . When the machinery cycles , the plastic material first of all injects up A .Since the fact that the vase embryo will remain the standard rush pith on , the vase embryo is living to turn on the standard not necessaries , and that traditional system goes up such as being living is stiff in that way .Hence , the machinery cycle that the overwhelming majority cooling may be living soon afterwards perioc through shuts the standard revolves up to become cool on the rush pith at the standard .Afterwards the cycle needs an extraordinary brief cooling perioc in order to permit the pattern to elucidate the pressure , injects and defends and to be getting near also is such in this way .Afterwards the plastic material are living B's surface is injected on this peak ministry face that the teeterboard was reachd in the indexing on one section when turning on the standard .As D before arrival when the extremity , now A is living teeterboard base place , and the push rod is switched on here , and the vase embryo is unloaded the finished piece through the machinery and leads to on the conveying utensil .Injecting the stroke adjust the cycle time not effect , as a result may complete more slowly .Gravitational force help is guarranteed that the finished piece breaks away from that the pattern drops secondly .The finished piece drops such the curtain squares formed by crossed lines tip conveying utensil on , and the probability that creates the surperficial gall is littleer . A ministry is living 、Gas dashing systematic twin vase embryo of forming supplys the face and becomes cool the place of back and base .
Since the fact that the vase embryo maintains the pattern standard rush pith on , the face obtains the conduction cooling included they are still convenient .Says in the total , the entire temperature of vase embryo than it is living traditional compression molding system and cooling leads to in the plank to stay analogous time will cool .
2、The Bottle Function
Significant respect that we analyse the indexing system analogous a of jar of vase that the embryo was manufacture out that to be the performance takeing this kind of vase that the vase embryo that the system was gived birth to was manufacture out against traditional work gived birth to on the cell one another contrasts .The comparand that obtaines in the eperiment that the table 1 is give out through is underway is depenied on . The indexing vase embryo performance is living and is better always in the intensity quiz , and this is better distributing for the runner quality which improved permits the stuff to be living inner place the vase , and does not there is the indication to make known that use this kind of system is living whatever space crystallinity of vase and ascendes .The indexing specimen gived birth to is probably equally light , for their weight distributions is to be much inseparable .
3、This kind of system distinguishing feature
Inner place the standard that to support with the hand the obviousest advantage of earthen brick is needs the cooling time decreased , thereby decreased entire time length that cycles .At the moment , this kind of system employ the largesttest breastwork thickly act as 4 millimeters the 47.3 grams vase embryos do .This kind of vase embryo process cycle time ascertains by measuring to 22.5 seconds , was optimum as to the overcast standard system .Overcast standard system implementation 14.2 seconds of indexing 48 cycle be able to be acquireed the better trade quality killing .The picture 2 is give out the cycle subdivided comparing situation .
Circling the control tower does not need the manipulator again .Like this , therefore decreased from the tradition system to go up the jam that the manipulator block created is giveed an alarm and the service ceases engine time .The finished piece peak has ariseed to be living not to be the inflexible cycle time the element .Decreased in the standard the turning on gap that needs in the wake of removing the manipulator , in the wake of decreasing of pattern stroke still lift empties cycle velocity .
Systematic another advantage is the floor area that needs decreases , along with thanks to does not there is manipulator and lead-out plank cooling system , latent capacity that the dependability of system may be liftd .Calculate in advance entire systematic dependability that therefore the manipulator obstructs does not happen permit the systematic usability to lift 30% .Merely traditional 48 55% of overcast areas that the standard system requires of indexing system floor area .Against the person who one another accompanies the yield that still possess per foot of floor area lifts further..
Employ the indexing systematically to cause an a jar of embryo runner quality obtain the modification .Being living , the valve runner district is freezed afterwards , the vase embryo is living brieflyer time inner place the heatpoint contact against the valve staff , for the cooling that the vase embryo is living inner place the overcast standard time by enormously decreases .Geing rid of this heat source removes a crystal source .Except for better vision effect , still causes that the runner district is more sturdy , thereby causes entire a of jar of side wall district better , and possess the weight that even more opportunitys ease the vase embryo in base district .
The vase embryo to remain at the standard rush pith elderer time .Systematically being contrastd against a criterion a jar of embryo mould plastics , entire a of jar of embryo becomes cool obtainning the modification .Being living , tradition manipulator becomes cool inner place the plank , and the finished piece is encounter and be able to be shrinked by the tube face becoming cool , and such heat transfer is imconsummate .In being living the indexing system manufactures at the standard shrinking on the rush pith , thereby maintain heat transfer , and is living when being come out , and will let drop when comprehensive entirety temperature of indexing vase embryo contrasts the a jar of embryo lead-out place through traditional system brings out by the peak .Still possesing , and designs as to the vase embryo at the moment , not to the throat standard ring district supply cooling water , being living , the peak when comeing out yet systematically will be cooled far more than the criterion .Become cool that district threshold energy system cycling as to the forming system of type .
The distinct stuffs of indexing system in the way of some kinds reaches the difference of two kinds of distinct stuffs testing with two kinds to gather designing to the benzol two methanoic acid glycol ester studs , and may catch sight of that the acetaldehyde ( AA ) amount lets drop always .a(chǎn)gainst injecting amount is contrastd this cycle time adjust injects the unit proposes the very much tall demand , injects the unit constinuously scousrs not to there is a few is held up time the stud .
Since the overcast standard of peak value inner place the pattern tallys with against the two differences studs , and against the difference process installation unanimously , the acetaldehyde is measured ever to possess to let drop that the main reason rests with that the pattern gathers materials the tube more .Second advantage may catch sight of in the way of the pattern at the moment is possesing the very much good weight
distributions , thereby permits to be living at the moment finished piece standard allows bad inside entire finished piece weight to drop the thest least degree .
4 、The injection mould design process requirementanalysis An injection mould design is composed of two steps: theinitial design and the detailed design. The initial design iscomposed of decisions made at the early stage of themould design, such as the type of mould configuration,the number of cavities, the type of runner, the type of gate and the type of mould base. The detailed design iscomposed of the insert (core/cavity) design, the ejectionsystem design, the cooling and venting component design,the assembly analysis and the final drafting.
To develop a good CAIMDS, an analysis of ‘whatthey have’ and ‘what they want’ needs to be performed.What they have:
– The customer’s requirements for the product. Thisincludes the detailed geometry anddimension requirementsof the product.
– An existing mould design library. This library coversthe standard or previously designedcomponents andassemblies of the mould design, for example, themould base (the fixed half and the moving half) andthe pocket (the fixed half and the moving half).
–An expert knowledge in injection mould design. Expertknowledge of both initial and detailed designs forthe injection mould is obtained mainly from experiencedmould designers. Such knowledge includesmaterial selection, shrinkage suggestion, cavity layoutsuggestion and others.
What they want:
– An intelligent and interactive mould design environment.Mould design is often composed of a series ofdesign procedures. These procedures usually requirecertain mould parts to be created and existing mouldparts to be assembled. Such a mould design environmentneed not be fully automatic, especially forcomplicated products with many undercuts. Anintelligent and interactive environment will be a goodchoice to integrate some useful automation algorithms,heuristic knowledge and on-lineinteraction by the experienced mould designer.
Standard/previous designed components/assemblies(product-independent parts) management. Apart from the core and cavity, an injection mould hasmany other parts that are similar in structure and geometrical shape that can be used in other injectionmould designs. These parts are independent of the plastic mould products. They are mostly standardcomponents that can be reused in different mould designs and mould sets.
– Useful tools (including solid design and analysiscalculation) in the core and the cavity (productdependentparts) design. Geometrical shapes and thesizes of the core and cavity system are determineddirectly by the mould product. All components insuch a system are product dependent. Also, theseparts are the critical components in the mould design Their geometrical requirements may be complicated.Thus, some tools developed to design the core and thecavity based on partial automation and partialinteraction can be quite useful.
– Design for assembly. In conventional CAD/CAMsystems, moulds are represented and stored as a complete geometric and topological solid model. Thismodel is composed of faces, edges and vertices in athree dimensional (3D) Euclidean space. Such a representationis suitable for visual display and performinggeometrically computation-intensive taskssuch as engineering analysis and simulation. However,this form is not appropriate for tasks thatrequire decision-making based on high-level
informationabout product geometric entities and theirrelationships. Mould designers prefer a design forassembly environment instead of a simple solid modelenvironment.
This idea is also presented in Ye et al.’s work [24].
– A design for manufacture. A complete injectionmould design development cycle can be composed ofthe mould design and mould manufacturing process.To integrate CAD/CAM into the mould design, themanufacturing features on the mould should be abstracteand analysed for the specific NC machine. Both the process plan and the NC code should beautomatically generated to enable the final designed mould to be manufactured.
– A design for engineering drawings. For manycompanies, the injection mould design has to be represented in the form of engineering drawingswith detailed dimensions. CAD/CAM tools that are able to automatically generate these engineeringdrawings from the final injection mould design will be useful.Based on the above analysis, our research focus is todevelop techniques to represent ‘what they have’ and‘what they want’.Representing ‘what they want’ is actually the representationof the knowledge and injection mould object.Developing ‘what they want’ means to integrate the representation with intelligent and interactive tools forthe injection mould design into a completed designenvironment. Therefore, an IKB-MOULD is proposedfor mould designers to realise the above two requirements
5、 Limitational factor of cycle velocity
Is living the entire cycle perioc to the indexing what cycles the effect element may be divided into five component part : (1)Machinery emptying cycle time ( this is completeing turning on the standard 、Circles the control tower 90 degrees , shuts standard and in the interest of injects acting the ready cycle time ) ; (2)The overcast standard charges to anticipate time ; (3)The demand is getting near in the interest of
averting the finished piece that becomes cool to take shape sunken guarantor ; (4)Becomes cool the pattern inner place the standard in order to cause through guarantor to be getting near perioc in the person who requires the standard the shuing force tonne figure elucidates the pressure ; (5)The vase embryo greats quantity of peak when comeing out being living warm that the face creating warms up along with warm up regeneration , in order to avert the follow-up handle perioc finished piece is fleeced the injury either is possess viscosity . Systematic machinery the emptying cycle time is optimized .The pattern need not turned on so manyly ,in order to permit the indexing to circle , such as the tradition systematically by permits themanipulator gos into the pattern district demand , thereby decreases turns on the standard with shuts the standard time .
Indexing velocity is also get in than the manipulator , and transfers finished piece and manipulator geting out quickly again .The machinery of 4.3 seconds at the moment empties to cycle sufficiently to optimize , and the margin of modification is very little .
Unduly little in case injecting the unit dimensions , the part