畢業(yè)論文外文翻譯-注射模具的介紹

1、the introdution of the injection mold1. mold basic knowledge1.1 introductionthere is a close relationship with all kinds of mold,which are refered to our daily production, and life in the use of the various tools and products, the large base of the machine tool, the body shell, the first embryo to a

2、 small screws, buttons, as well as various home appliances shell. mold's shape determine the shape of these products, mold's precision and machining quality determine the quality of these products,too. because of a variety of products, appearance, specifications and the different uses,mold d

3、evide into die casting into the mould, die forging, die-casting mould, die, and so on other non - plastic molds, as well as plastic mold. in recent years, with the rapid development of the plastics industry, and gm and engineering plastics in areas such as strength and accuracy of the continuous enh

4、ancement , the scope of the application of plastic products have also constantly expanded, such as: household appliances, instrumentation, construction equipment, automotive, daily hardware, and many other fields, the proportion of plastic products is rapidly increasing. a rational design of plastic

5、 parts often can replace much more traditional metal pieces. the trend of industrial products and daily products plasticed is rising day after day.1.2 mold general definitionin the industrial production, with the various press and the special instruments which installed in the press,it produces the

6、required shape parts or products through pressure on the metal or nonmetallic materials, this special instruments collectively call as the mold.1.3 mold general classificationmold can be divided into plastic and non - plastic mould: (1) non-plastic mould: die casting, forging die, die, die-casting m

7、ould and so on. a. die casting - taps, pig iron platformb. forging die - car body c. die - computer panel d. die casting die - superalloy, cylinder body (2) for the production technology and production, the plastic mold are divided into different products: a. injection molding die tv casing, keyboar

8、d button (the most common application) b. inflatable module - drink bottles c. compression molding die - bakelite switches, scientific ciwan dish d. transfer molding die - ic products e. extrusion die - of glue, plastic bags f. hot forming die - transparent shell molding packaging g. rotomoulding mo

9、de - flexible toy doll. injection molding is the most popurlar method in plastics producing process. the method can be applied to all parts of thermoplastic and some of thermosetting plastics, the quantity of plastic production is much more than any other forming method.injection mold as one of the

10、main toolsof injection molding processing,whosh production efficiency is low or high in the quality of precision、 manufacturing cycle and the process of injection molding and so on.directly affect the quality of products, production, cost and product updates, at the same time it also determines the

11、competitiveness of enterprises in the markets response capacity and speed. injection mold consists of a number of plate which mass with the various component parts. it divided into: a molding device (die, punch)b positioning system (i. column i. sets) c fixtures (the word board, code-pit) d cooling

12、system (carrying water hole) e thermostat system (heating tubes, the hotline) f-road system (jack tsui hole, flow slot, streaming road hole) g ejection system (dingzhen, top stick).1.4 type of moldit can be divided into three categories according to gating system with the different type of mold :(1)

13、 intake die: runner and gate at the partig line,it will strip together with products when in the open mode,it is the most simple of design, easy processing and lower costing.so more people operations by using large intake system. (2) small inlet die:it general stay in the products directly,but runne

14、r and gate are not at the partig line.therefore.it should be design a multi-outlet parting line.and then it is more complex in the designing, more difficult in processing, generally chosing the small inlet die is depending on the product requirements. (3) hot runner die:it consists of heat gate, hea

15、t runner plate, temperature control box. hot runner molds are two plate molds with a heated runner system inside one half of the mold. a hot runner system is divided into two parts: the manifold and the drops. the manifold has channels that convey the plastic on a single plane, parallel to the parti

16、ng line, to a point above the cavity. the drops, situated perpendicular to the manifold, convey the plastic from the manifold to the part. the advantages of hot runner system : (l )no outlet expected, no need processing, the whole process fully automated, save time and enhance the efficiency of the

17、work. (2) small pressure loss.2、injection moldthere are many rules for designing molds.these rules and standard practices are based on logic,past experience,convenience,and economy.for designing,mold making,and moldingjt is usually of advantage to follow the rulesbut occasionally jt may work out bet

18、ter if a rule is ignored and an alternative way is selected.in some texts,the most common rules are noted,but the designer will learn only from experience which way to go.the designer must ever be open to new ideas and methods,to new molding and mold material that may affect these rules.the process

19、consists of feeding a plastic compound in powdered or granular form from a hopper through metering and melting stages and then injecting it into a mold.injection molding process: mold is a production of plastic tool. it consists of several parts and this group contains forming cavities. when it inje

20、cts molding, mold clamping in the injection molding machine, melting plastic is injected forming cavities and cooling stereotypes in it, then it separate upper and lower diejt will push the production from the cavity in order to leave the mold through ejection system, finally mold close again and pr

21、epared the next injection. the entire process of injection is carried out of the cycle.an injection mold consists of at least two halves that are fastened to the two platens of the injection molding machine so that can be opened and closed.in the closed position,the product-forming surfaces of the t

22、wo mold halves define the mold cavity into which the plastic melt is injected via the runner system and the gate.cooling provisions in the mold provide for cooling and solidification of the molded product so that it can be subsequently ejected.for product ejection to occur,the mold must open.the sha

23、pe of the molded product determines whether it can be ejected simply by opening the two mold halves or whether undercuts must be present.the design of a mold is dictated primarily by the shape of the product to be molded and the provisions necessary for product ejection.injection-molded products can

24、 be classified as:1) .products without undercuts.2) .products with external undercuts of lateral openings.3) .products with internal undercuts.4) .products with external and internal undercuts.3. the composition of injection mold3.1 mold cavity spacethe mold cavity space is a shape inside the mold.w

25、hen the molding material is forced into this space it will take on the shape of the cavity space.in injection molding the plastic is injected into the cavity space with high pressure,so the mold must be strong enough to resist the injection pressure without deforming.3.2 number of cavitiesmany molds

26、,particularly molds for larger products,ate built for only 1 cavity space,but many molds,especially large production molds,are built with 2 or more cavities.the reason for this is purely economical.lt takes only little more time to inject several cavities than to inject one.today.most multicavity mo

27、lds are built with a preferred number of cavities:2,4,6,8,12,16,24,32,48,64,9628.these numbers are selected because the cavities can be easily arranged in a rectangular pattern,which is easier for designing and dimensioning,for manufacturing,and for symmetry around the center of the machine 9which i

28、s highly desirable to ensure equal clamping force for each cavity.3.3 cavity and coreby convention,the hollow portion of the cavity space is called the cavity.the matching,often raised portion of the cavity space is called the core.most plastic products are cup-shaped.this does not mean that they lo

29、ok like a cup,but they do have an inside and an outside.the outside of the product is formed by the cavity, the inside by the core.usually,the cavities are placed in the mold half that is mounted on the injection side,while the cores are placed in the moving half of the mold.the reason for this is t

30、hat all injection molding machines provide an ejection mechanism on the moving platen and the products tend to shrink onto and cling to the core,from where they are then ejected.most injection molding machines do not provide ejection mechanisms on the injection side.for moulds containing intricate i

31、mpressions,and for multi-impression moulds, it is not satisfactory to attempt to machine the cavity and core plates from single blocks of steel as with integer moulds. the cavity and core give the molding its external and internal shapes respectively, the impression imparting the whole of the form t

32、o the molding.3.4 the parting lineto be able to produce a mold,we must have ta least two separate mold halves,with the cavity in one side and the core in the other.the separation between these plates is called the parting line,and designated p/l.actually,this is a parting area or plane9but,by cinven

33、tionjn this intext it is referred to as a line. the parting surfaces of a mould are those portion of both mould plates, adjacent to the impressions, which butt together to form a seal and prevent the loss of plastic material from the impression.the parting line can have any shape, many moldings are

34、required which have a palling line which lies on a non-planar or curved surface,but for ease of mold manufacturingjt is preferable to have it in one plane.the parting line is always at the widest circumference of the product,to make ejection of the product from the mold possible.with some shapes it

35、may be necessary to offset the p/l,or to have it at an angle.but in any event it is best to have is so that itan be easily machined,and often ground, to ensure that it shuts off tightly when the mold is clamped during injectionjf the parting line is poorly finished the plastic will escape.which show

36、s up on the product as an unsightly sharp projection,which must then be removed;otherwise,the product could be unusablethere is even a danger that the plastic could squirt out of the mold and do personal danger.3.5 runners and gatesnow,we must add provisions for bringing the plastic into these cavit

37、y spaces.this must be done with enough pressure so that the cavity spaces are filled completely before the plastic n freezes11 (that is,cools so much that the plastic cannot flow any more).the flow passages are the sprue,from wherethe machine nozzle contactss the mold.the runners.which distribute th

38、e plastic to the individual cavities, the wall of the runner channel must be smooth to prevent any restriction to flow. also, as the runner has to be removed with the molding, there must be no machine marks left which would tend to retain the runner in the mould plate.and the gates which are small o

39、penings leading from the runner into the cavity space. the gate is a channel or orifice connecting the runner with the impression. it has a small cross-sectional area when compared with the rest of the feed system. the gate freezes soon after the impression is filled so that the injection plunger ca

40、n be withdrawn without the probability of void being created in the molding by suck-back.4. the injection molding machine processinjection mold is installed in the injection molding machine, and its injection molding process is completed by the injection molding machine. following is the injection m

41、olding machine process.the molding machine uses a vacuum to move the plastic from the dryer to it's initial holding chamber. this chamber is actually a small hopper on the back of the "barrel” of the machineo the barrel is where all the real work is done and itfs essentially a large screw h

42、oused in a heater which moves the plastic closer to the mold. as the screw turns, the plastic traverses the barrel and reaches a molten state. only when its molten can it be injected into the mold with a rapid turn of the screw. as the chamber in front of the screw becomes filled, it forces the scre

43、w back, tripping a limit switch that activates a hydraulic cylinder that forces the screw forward and injects the fluid plastic into the closed mold. the gate freezes soon after the impression is filled so that the injection plunger can be withdrawn without the probability of void being created in t

44、he molding by suck-back. the tip of the barrel is called the "nozzle" and from this point to the cavity in the mold the material is not heated and is constantly cooling. the hrunnerh is the cooled/set plastic that extends from the nozzle to the cavity and is process scrap. actually, the co

45、oled material from the nozzle to the mold is the hsprueh but its connected to the runner. there are ways around having sprues and runners, but its beyond the scope of what werre talking about here most people have probably seen runners before and not realized it. the most likely place to see them ar

46、e in model airplane/car kits as the individual components are left attached to the runner system. typically the runners are ejected into a chute below the mold or else they will be picked out of the mold by a robotic arm and dumped into a regrinder. the regrinder chops the runners into bits and prep

47、ares them to be moved back into the dryer.though, once plastic has been heated, it degrades a bit and some molding processes willnot allow for hregrindh to be mixed back in with virgin material as it can cause problems with the final part. in cases like this the regrind is used elsewhere or it is di

48、scarded completely. shrinkage plays a crucial role in molding and most plastic shrinks 20% as it cools. in order to combat this phenomenon in critical plastic pieces (not really toys) it is up the mold designer to build this factor into his design so that the finished parts will meet the original pr

49、oduct design specifications. nejector pinsh are part of the mold itself and are used to push the molded parts from the cavity once the mold is opened. this ejecting process is controlled by the molding machine. the molding cycle is basically nclose - shoot open - eject”. the mold is clamped into the

50、 machine with the front half remaining stationary (on the baitel side of the machine) and the back half being the movable half. also on this movable half are the ejector pins that push the molded parts from the cavity. the parting surfaces of a mould are those portion of both mould plates, adjacent

51、to the impressions, which butt together to form a seal and prevent the loss of plastic material from the impression.when all molds open up, the parts are stuck to the back half of the mold so that they can be ejected with the built-in pins.these are related to the introduction of the injection mold.

52、注射模具的介紹1 模具基本知識(shí)l1引言我們h常生產(chǎn)、生活中所使用到的各種工具和產(chǎn)品，大到機(jī)床的底座、機(jī)身外殼， 小到一個(gè)胚頭螺絲、紐扣以及各種家用電器的外殼，無不與模具有著密切的關(guān)系。模具 的形狀決定著這些產(chǎn)品的外形，模具的加工質(zhì)量與精度也就決定著這些產(chǎn)品的質(zhì)量。因 為各種產(chǎn)品的材質(zhì)、外觀、規(guī)格及用途的不同，模具分為了鑄造模、鍛造模、壓鑄模、 沖壓模等非射膠模具，以及射膠模具。近年來，隨著射料工業(yè)的飛速發(fā)展和通用與工程 射料在強(qiáng)度和精度等方面的不斷提高，射料制品的應(yīng)用范圍也在不斷擴(kuò)大，如：家用電 器、儀器儀表，建筑器材，汽車工業(yè)、日用五金等眾多領(lǐng)域，射料制品所占的比例正迅 猛增加。一個(gè)設(shè)計(jì)合理

53、的射料件往往能代替多個(gè)傳統(tǒng)金屈件。工業(yè)產(chǎn)品和日用產(chǎn)品射料 化的趨勢(shì)不斷上升。般定義在工業(yè)生產(chǎn)中，用各種壓力機(jī)和裝在壓力機(jī)上的專用工具，通過壓力把金屬或非金 屬材料制出所需形狀的零件或制品，這種專用工具統(tǒng)稱為模具。1.3模具的般分類可分為射膠模具及非射膠模具：（1）非射膠模具有：鑄造模、鍛造模、沖壓模、 壓鑄模等。a.鑄造模水龍頭、生鐵平臺(tái)b.鍛造模汽車身 c.沖壓模 計(jì)算機(jī)面板 d.壓鑄模超合金，汽缸體 （2）射膠模具根據(jù)生產(chǎn)工藝和生產(chǎn)產(chǎn) 品的不同又分為：a.注射成型模電視機(jī)外殼、鍵盤按鈕（應(yīng)用最普遍）b.吹氣 模飲料瓶 c.壓縮成型模電木開關(guān)、科學(xué)瓷碗碟d.轉(zhuǎn)移成型模集成 電路制品e.擠壓成

54、型模膠水管、射膠袋f.熱成型模透明成型包裝外 殼g旋轉(zhuǎn)成型模軟膠洋娃娃玩具注射成型是射料加工屮最普遍采用的方法。該方法適用于全部熱射性射料和部分熱 固性射料，制得的射料制品數(shù)量z大是其它成型方法望塵莫及的，作為注射成型加工的 主要工具z的注射模具，在質(zhì)量精度、制造周期以及注射成型過程屮的生產(chǎn)效率等方 面水平高低，直接影響產(chǎn)品的質(zhì)量、產(chǎn)量、成本及產(chǎn)品的更新，同時(shí)也決定著企業(yè)在市 場(chǎng)競(jìng)爭(zhēng)屮的反應(yīng)能力和速度。注射模具是由若干塊鋼板配合各種零件組成的，基本分 為：a成型裝置（凹模，凸模）b定位裝置（導(dǎo)柱，導(dǎo)套）c固定裝置（工字板, 碼?？樱ヾ冷卻系統(tǒng)（運(yùn)水孔）e恒溫系統(tǒng)（加熱管，發(fā)熱線）f流道系統(tǒng)（唧

55、 咀孔，流道槽，流道孔）g頂出系統(tǒng)（頂針，頂棍）1.4模具的類型根據(jù)澆注系統(tǒng)型制的不同可將模具分為三類：（1）大水口模具：流道及澆口在分模 線上，與產(chǎn)品在開模時(shí)一起脫模，設(shè)計(jì)最簡(jiǎn)單，容易加工，成本較低，所以較多人采用 大水口系統(tǒng)作業(yè)。（2）細(xì)水口模具：流道及澆口不在分模線上，一般直接在產(chǎn)品上， 所以要設(shè)計(jì)多一組水口分模線，設(shè)計(jì)較為復(fù)雜，加工較困難，一般要視產(chǎn)品要求而選用 細(xì)水口系統(tǒng)。（3）熱流道模具：主要由熱澆口套，熱澆道板，溫控電箱構(gòu)成。熱流道 模具是在一個(gè)半模有流道加熱系統(tǒng)的兩板式模具。熱流道系統(tǒng)分成兩個(gè)部分：分流板和 噴嘴。分流板的通道將射料傳送到一個(gè)和分型線平行平面，這個(gè)平面在型腔的上

56、面。噴 嘴乖直于分流板安裝，把射料從分流板送進(jìn)行腔。熱流道系統(tǒng)的優(yōu)勢(shì)：（1）無水口料， 不需要后加工，使整個(gè)成型過程完全自動(dòng)化，節(jié)省工作時(shí)間，提高工作效率。（2）壓 力損耗小。2. 注射模設(shè)計(jì)模具有很多的規(guī)則。這些規(guī)則和標(biāo)準(zhǔn)的做法，都是基于邏輯，過往的經(jīng)驗(yàn)，方 便性，經(jīng)濟(jì)性。設(shè)計(jì)，模具制造，和成型，它通常的優(yōu)勢(shì)就是遵循規(guī)則。但有吋候，它 可能會(huì)做出更好的，如果一項(xiàng)方法是被忽視和另一種方法被選擇。在一些書中，最普通的 規(guī)則都會(huì)一一列出，而設(shè)計(jì)者設(shè)計(jì)的東西也僅僅是跟著以往的經(jīng)驗(yàn)走而已。設(shè)計(jì)者應(yīng)該研 究岀新的想法和方法，來進(jìn)行新的成型和選擇模具材料。注射工藝過程就是從給料斗送進(jìn)粉狀或粒狀的射料混合物

57、，經(jīng)過定量區(qū)和熔化區(qū)， 然后將其注射到模具型腔中。注射過程說明：模具是一種生產(chǎn)射料制品的工具。它由幾 組零件部分構(gòu)成，這個(gè)組合內(nèi)有成型模腔。注射時(shí)，模具裝夾在注射機(jī)上，熔融射料被 注入成型模腔內(nèi)，并在腔內(nèi)冷卻定型，然后上下模分開，經(jīng)由頂出系統(tǒng)將制品從模腔頂出離開模具，最后模具再閉合進(jìn)行下一次注射，整個(gè)注射過程是循環(huán)進(jìn)行的。注射模至少是由裝在注射機(jī)的兩個(gè)壓板上的兩部分組成，以便可以開模和合模。在 合模的時(shí)候，模具的兩半部分形成的產(chǎn)品成型表面是由射料熔體通過澆口和熱流道系統(tǒng) 注入模具型腔形成的。模具中冷卻的原則是產(chǎn)品要在模具中冷卻和凝固，以便隨后可以脫 模。隨著產(chǎn)品注射的完成，模具就必須開模。產(chǎn)品

58、的形狀決定著它是否由模具兩部份簡(jiǎn)單 地開?；蛴捎袀?cè)向分型來開模。模具的設(shè)計(jì)是由產(chǎn)品的形狀和產(chǎn)品開模的方式?jīng)Q定的。 注射成型的產(chǎn)品可以分為以下幾類：無側(cè)抽芯的產(chǎn)品；有側(cè)向開口的外側(cè)抽芯的產(chǎn)品；有內(nèi)側(cè)抽芯的產(chǎn)品；有外側(cè)抽芯和內(nèi)側(cè)抽芯的產(chǎn)品。3. 注射模具的組成3.1型腔空間型腔空間是在模具中的一個(gè)形狀，當(dāng)注射的材料充滿這個(gè)空間的時(shí)候,它就會(huì)呈現(xiàn)出 和型腔空間一樣的形狀。在注射成型吋，射料是通過很高的壓力注射入型腔空間的，所以 模具必須要足夠的堅(jiān)固來抵抗注射的壓力，以防變形。3.2型腔的數(shù)量許多的模具，特別是較大產(chǎn)品的模具，僅僅只有一個(gè)模具型腔，但是也有許多的模 具，特別是比較大型的模具，都會(huì)有2個(gè)

59、或更多的型。究其原因就是它純粹的經(jīng)濟(jì)性。 它僅僅是注入多個(gè)型腔比注入一個(gè)型腔多花了一點(diǎn)的時(shí)間。今天，大多數(shù)的模具型腔數(shù)量 都是以這些數(shù)字為參考的：2,4,6,& 12,16,24,32,4&64,96,128。選擇這些數(shù)字（偶數(shù)）的原 因是為了在長(zhǎng)方形區(qū)域內(nèi)布置型腔方便，這樣就有利于設(shè)計(jì)、定尺寸、加工制造和圍繞 機(jī)器中心對(duì)稱，這種對(duì)稱分布對(duì)于保證每個(gè)型腔分配到相同的鎖模力非常重要。3.3型腔和型芯按照習(xí)慣，腔空間的中空部分稱為型腔。與型腔空間所匹配的部分稱為型芯。大 部分射膠制品是杯形的。但這并不意味著它們看起來就像是一個(gè)杯，只是它們有一個(gè) 內(nèi)部和外部。產(chǎn)品的外部是由型腔形成的，而內(nèi)部是有由型芯形成的。通常情況下，型腔 是位于注射一邊的那半模具上，而型芯是位于可以移動(dòng)的那半模具上的。這樣安排的原因 是注射機(jī)上的移動(dòng)板有一個(gè)彈射裝置，而產(chǎn)品是收縮和包緊在型芯上的，然后產(chǎn)品就可以 通過此來彈射出來。大部分的注射機(jī)在注射的一邊都不會(huì)安裝彈射裝置。對(duì)于模具包含復(fù)雜型腔和多型腔模具，試圖象