注塑模具毕业设计说明书(7)

天津职业技术师范大学2011届本科生毕业设计

The outside side sprinkles

Fan-shaped sprinkle: in common use to model the width bigger thin slice-like in shape Su piece

The even sew type sprinkles

Protect an ear type to sprinkle The Xi type sprinkles

I am a little bit general to sprinkle

Incubate a type to sprinkle (my company mostly adopts a this kind way) The dish wreath type sprinkles The round Fu type sprinkles The claw form sprinkles

Wreath form in the park sprinkles

3>.Sprinkle the choice of a people's position

(1)Sprinkling a people's choice has already impeded the thing recent distance.

(2)Sprinkling size and position choice should avoid creation jet and peristalsis.

(3)Sprinkling should set up the cross section thickest place at the Su piece. (4)The choice that sprinkles a people's position should make plastics process the shortest and anticipate flow to change to minimal.

(5)Sprinkle a people position choice should ejecting of air inside been advantageous to chamber.

(6)The choice that sprinkles a people's position should reduce or keep welding of Su piece scar increment from welding a prison degree.

(7)The choice that sprinkles a people's position should prevent from anticipating flow type chamber, type pistil, the fore piece squeezes to transform.

(Four).Cold anticipate cave

1.Structure:cold anticipate cave is use to keep to inject partition to produce for period of cold anticipate a head, prevent from cold anticipate got into chamber but influence Su piece quality, and make the Hot anticipated can successfully been full of chamber, cold anticipate cave and call cold anticipate well.

2. Pull to anticipate a form:

(1)The hook-like (work form) pulls to anticipate a pole (2)The spheroid pulls to anticipate a pole 3. The cone form pulls to anticipate a pole

4. Pull to anticipate cave: A. Take a pole; B. Don't take a pole

The type of the molding tool chamber and type the Core forms a Su piece respectively inner part and external shape, the type chamber shape comes to a decision Su piece shape and connect down a synopsis to explain to choose which way pair of type chamber and type the Core install in the molding tool. These ways can induce to two major types. Namely whole type and inset a put together

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天津职业技术师范大学2011届本科生毕业设计

type. Another way that is to go a chamber is to join to put together a piece or slippery piece of.

When type chamber or type the Core is processed by a piece of big steel plate or the steel bloom but become, or cast integral whole, while doing not need to use to prop up a piece but form a piece of template constitute a whole type chamber plank or type Core plank. This design because of have high strength, the size is small and cost low characteristic, but main application at monotype chamber molding tool in. Whole type chamber and type the Core is general need not in several chamber molding tools, because several chamber molding tools had to consider some other factors while, for example install a combination to inset an etc..

For model molding tool and several chamber molding tool of part complications, be like a whole type molding tool to use a piece of steel material processed chamber and type Core so not easy. If adopt whole type structure, then process in proper order and the operation process will become very complicated, the cost is also high, therefore inset a put together type assemble method to act for a whole type.

Inset a put together type the chamber is processed by the small steel bloom but become, small steel bloom after processing conduct and actions inset a piece, on the contrary, the been called chamber of formation type chamber part insets a piece. Then, these inset a piece to firmly install at is called a plastic sheet of air, the plastic sheet is processed by the solid steel plate or the steel bloom but becomes. At after a kind of method, the department still needs to increase a piece of template and has already reinforced a function after the plastic sheet and ensure that a piece to install is good enough.

Whole type and inset a put together type, the structure all has an advantage, this be decided by a Su piece size and shape, molding tool of complicated degree, is the monotype chamber a molding tool still several chamber molding tools and the manufacturing cost of the molding tool what to need etc.. Usually, after the characteristics, such as shape and size...etc. of Su piece is certain, adoption which way of type chamber and type the Core have been already made sure.

Slippery piece of

In the design, slip a piece the emplacement is in having the template of direction function, and can hit machine dint or hydraulic dint to follow flat surface to exercise under the function. Slip a piece to firmly lock tightly in the appropriate position from tight piece of molding tool another piece of template. Drive slippery piece of produce the opposite template exercises of the way include inclined lead a pillar, curved cam to pack compression spring coil and hydraulic system. The cam drives the basic way of slippery piece of sport as follows: Install in the cam of settling the mold part to arouse while a mold slippery piece of follow move template to glide to a side.

Inclined slippery piece of

In this design, slippery piece of gearing at move a mold set plank in, move a mold set the plank constituted the sport part of molding tool. Slippery piece

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天津职业技术师范大学2011届本科生毕业设计

follows inclination direction outwardly move, make the Su piece side cave convex part completion taken out Core sport. Slippery piece of usually from release organization to drive, tilt to one side a direction at slippery piece there isn't key function on the direction. After matching a mold, slip a passive mold set of a piece of organization plank fixedly on the appropriate position. Guidance system's needing a contented condition is slippery the piece have to be limited on the template, and follow appointed direction ambulation.

Take to have special drive a driving of way of the system like bottom a few kinds: Inclined lead to sell to drive; cam drives; The spring coil drives.

Cooling system

The basic principle that notes Su production goes the chamber to the heat Hot body infusion molding tool and quickly off inside the Hot body's experienced chamber solid turn temperature, and keep certain shape. Because the molding tool temperature controls a Su piece to some extent of whole model a period, consequently count for much in the production. The Hot body flow fluency in the heat molding tool, but solid the piece Su release a front, certain of cooling the stage is an essential to have. Zero on the other hand, the Hot body is solid in the temperature lower molding tool and turn a little bit quickly and again to result in Su piece the bitter end fill disaffection. Consequently have to win election to choose a balance point in the condition of these two kinds of oppositions to acquire the best production circulation.

The work temperature of molding tool has something to do with several sowing the cause a vegetable, including the grade and type, the fluxion route in the Hot body's experienced chamber and Su piece of modeling the material the wall is thick and sprinkles to note system length...etc.. Use this Chong mold to request slightly high temperature that noting Su is more beneficial. Like this the Su piece of production welds a scar little, flow a scar not and obviously, other blemishes also less, therefore can raise a Su piece surface quality.

In order to keep the difference in temperature that the molding tool and Su piece Hot body needs, water is in the passage or bore on the molding tool circulation. These bores are called to flow or waterway, the whole waterway fastens to know together as to cool off circulatory system.

At Chong mold stage, the tallest Hot body of temperature is located on import, they sprinkle a people neighborhood; The temperature lowest Hot body is located on an importing farthest place of distance. When the cooling lies quality in the circulation inside the molding tool, lying the quality temperature will go up. Therefore, for is Su piece the surface acquire even cooling velocity, cooling off the entrance of passage should set up a piece the neighborhood is at the heat Su and be subjected to hot after the cooling lie quality temperature to go up, exporting to set up a piece the neighborhood is at the low temperature Su. However have the underneath the discussion can know, this kind of ideal appearance isn't always viable. In order to avoid otiose molding tool waste, design this usually with lend experience design cooling waterway.

Cool off the parts that water hush money needs just can buy on the market.

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天津职业技术师范大学2011届本科生毕业设计

These parts pass soft tube and molding tool directly and connect together and pass these parts the cooling back track of the formation the type impossibly and by the square control molding tool temperature.

The responsibility that provides is a suitable cooling system type to design this for the molding tool. Usually, the simplest cooling system lengthways drills a bore on the template. However for the precise molding tool, this isn't the most effective cooling method.

Cooling off the waterway can not be apart from to agree on any other teaching of template too near, this makes the layout that cools off a back track usually more complicated. Exists a great deal of teaching of Confucius on the template or hollow, use to gearing to push a pole, lead pillar, lead a set and sprinkle a people's set and inset an etc.. The safe distance that cools off waterway with of other teaching of is to a large extent decided by the drilling of cooling waterway needed into the depth. When flow a depth was deeper, the auger deviate the trend of processing the route of scheduling to again.

In order to acquire the best cooling back track, the design considered in the early years that the position that cooled off a back track didn't lose to a kind of good way. Other molding tool spare parts, if push a pole and lead a set of etc., can be a ground of assurance to install position.

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天津职业技术师范大学2011届本科生毕业设计

模具结构

随着塑料工业的飞速发展及塑料制品在各个领域的推广应用，产品对模具的要求也越来越高。同时也对专业设计人员的经验提出了更高的要求，在塑料制品模具设计时制品材料的选择是决定产品性能的重要因素。还有制品壁厚等问题是辅助设计软件所不能解决的，要需要专业设计人员长时间经验的积累才能做好的。因此本文就塑料制品模具设计中若干重要问题做以简要的讨论。

在我国塑料工业发展中，计算机的应用起到了重要作用。计算机技术在模具设计领域的应用，大大缩短了模具设计时间，尤其计算机辅助工程（ＣＡＥ）技术的大规模推广，解决了塑料产品开发、模具设计及产品加工中的薄弱环节。更在提高生产率、保证产品质量、降低成本等方面体现出现代科技的优越性。但是现代技术并不能替代专业设计人员的经验，在塑料模具设计时制品材料的选择是决定模具设计时模具材料选用的重要因素。怎样选用合适的材料，是模具设计中一个重要的问题。 塑料制品材料的选用对模具设计的影响

一般来说，并没有不好的材料，只有在特定的领域使用了错误的材料。因此，设计者必须要彻底了解各种可供选择的材料的性能，并仔细测试这些材料，研究其与各种因素对成型加工制品性能的影响。本文只就传统的热塑性材料进行分析以说明问题。在注射成型中最常用的是热塑性塑料。它又可分为无定型塑料和半结晶性塑料。这两类材料在分子结构和受结晶化影响的性能上有明显不同。一般来说，半结晶性热塑性塑料主要用于机械强度高的部件，而无定型热塑性塑料由于不易弯曲，则常被应用于外壳。这是材料选用的大框，其次，还要根据填料和增强材料继续选择。 根据填料和增强材料进行选择的分析

热塑性塑料可分为未增强、玻璃纤维增强、矿物及玻璃体填充等种类产品。玻璃纤维主要用于增加强度、坚固度和提高应用温度；矿物和玻纤则具较低的增强效果，主要用于减少翘曲。玻璃纤维会影响到成型加工，尤其会对部件产生收缩和翘曲性。所以，玻璃纤维增强材料不能被未增强热塑性塑料或低含量增强材料来替代，而不会有尺寸改变。玻璃纤维的取向由流动方向决定，这将引起部件机械强度的变化。试验（从注射成型片的横向和纵向截取了10个测试条，并在同一个拉力测试仪上对它们的机械性能进行了比较）表明，对添加了30％玻璃纤维增强的热塑性聚酯树脂，其横向的拉伸强度比纵向（流动方向）低了32％，挠曲模量和冲击强度分别减少了43％和53％。 在综合考虑安全因素的强度计算中，应注意到这些损失。

在一些热塑性塑料中加入了一系列增强材料、填料和改性剂来改变它们的性质。由这些添加剂产生的性能变化必须认真地从手册或数据库中查阅，更好的是听取原材料制造厂家的专家的技术建议。以选用最为合适的材料。

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