湖南涉外经济学院本科生毕业论文（设计）
参考文献
[1] 叶久新,王群.塑料成型工艺及模具设计[M].北京:机械工业出版社,2013.
[2] 伍先明,陈志刚,杨军,李云义.塑料模具设计指导（第3版）[M].北京:国防大学出版社,2014. [3] 濮良贵.机械设计（第八版）[M].北京:高等教育出版社,2006. [4] 成大仙.机械设计手册（第5版）[M].北京:化学工业出版社,2007. [5] 陈于萍.互换性与测量技术基础[M].北京:机械工业出版社,2008. [6] 齐晓杰.塑料成型工艺与模具设计[M].北京:机械工业出版社,2006. [7] 许发樾.实用模具设计与制造手册[M](第2版).北京:机械工业出版社,2005. [8] 王鹏驹,张杰.塑料模具设计师手册[M].北京:机械工业出版社,2008.
[9] 刘潭玉,黄兴梅,张爱军.画法几何及机械制图(第二版)[M].湖南:湖南大学出版社,2005. [10] 徐学林.互换性与测量技术(第二版)[M].湖南:湖南大学出版社,2009. [11] 李玉锡.机械设计课程设计[M].北京:高等教育出版社,2008. [12] 黄弘毅，李明.辉模具制造工艺[M].北京:机械工业出版社,2011. [13] 曹阳根.塑料模具设计技术英语[M].北京:化学工业出版社,2009. [14] 张彤,樊红丽，焦永和.机械制图[M].北京:北京理工大学,2006. [15] Parrilla A, Guerrero A(1994) Chem senses 1:9-10.
[16]江洪,郦祥林.UG NX7.0基础教程第4版[M].北京:机械工业出版社,2011. [17]黄星.模具专业英语[M].北京:人民邮电出版社,2009.
[18]Chicago Tribune,”Gun Injuries Take Financial Toll on Hospitals,” February 24,1994.
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湖南涉外经济学院本科生毕业论文（设计）
致 谢
毕业设计洗发水盖已经完成了，同时设计的这段时间，我查阅了很多资料，修改过多次设计说明书，有过想放弃的想法，心浮气躁，让我不能继续往下设计。但是最终还是在磕磕碰碰设计中完成了设计说明书。
在这里我要谢谢我们的导师曹申老师帮助我答疑我不会的问题，指导设计的正式方法。给我们找有关设计相关的软件和资料，并且一对一的商讨设计存在的问题。解决了我在设计中碰到的问题。在选题到设计再到中期设计若是木有得到老师的及时帮助，我不可能完成这个设计。还有感谢我的同学给我的帮助，让我在设计中找到了不要任意放弃的精神，是你们的鼓励让我完成了这次设计。同时要感谢辅导员老师在大学四对我们的教导，在这四年中学习到了为人处事的道理，并且见识到知识是多么的重要，进一步来说是专业知识非常重要，所以还要感谢所有的授课老师对我们在课堂上的分析。最后感谢陪我一起走过的同学兄弟，朋友们，因为有你们我在大学四年才有丰富的人生，有你们在奋斗的路上我才会感觉不到孤独。谢谢你们。
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湖南涉外经济学院本科生毕业论文（设计）
附录A：专业英语原文
Injection Molding
Many different processes are used to transform plastic granules, powders, and liquids into product. The plastic material is in moldable form, and is adaptable to various forming methods. In most cases thermosetting materials require other methods of forming. This is recognized by the fact that thermoplastics are usually heated to a soft state and then reshaped before cooling. Thermoses, on the other hand have not yet been polymerized before processing, and the chemical reaction takes place during the process, usually through heat, a catalyst, or pressure. It is important to remember this concept while studying the plastics manufacturing processes and polymers used.
Injection molding is by far the most widely used process of forming thermoplastic materials. It is also one of the oldest. Currently injection molding accounts for 30% of all plastics resin consumption. Since raw material can be converted by a single procedure, injection molding is suitable for mass production of plastics articles and automated one-step production of complex geometries. In most cases, finishing is not necessary. Typical products include toys, automotive parts, household articles, and consumer electronics goods. Since injection molding has a number of interdependent variables, it is a process of considerable complexity. The success of the injection molding operation is dependent not only in the proper setup of the machine hydraulics, barrel temperature variations, and changes in material viscosity. Increasing shot-to-shot repeatability of machine variables helps produce parts with tighter tolerance, lowers the level of rejects, and increases product quality (i.e., appearance and serviceability).
The principal objective of any molding operation is the manufacture of products: to a specific quality level, in the shortest time, and using repeatable and fully automatic cycle. Molders strive to reduce or eliminate rejected parts in molding production. For injection molding of high precision optical parts, or parts with a high added value such as appliance cases, the payoff of reduced rejects is high.
A typical injection molding cycle or sequence consists of five phases; 1. Injection or mold filling 2. Packing or compression 3. Holding 4. Cooling 5. Part ejection
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湖南涉外经济学院本科生毕业论文（设计）
Plastic granules are fed into the hopper and through an in the injection cylinder where they are carried forward by the rotating screw. The rotation of the screw forces the granules under high pressure against the heated walls of the cylinder causing them to melt. As the pressure building up, the rotating screw is forced backward until enough plastic has accumulated to make the shot. The injection ram (or screw) forces molten plastic from the barrel, through the nozzle, sprue and runner system, and finally into the mold cavities. During injection, the mold cavity is filled volumetrically. When the plastic contacts the cold mold surfaces, it solidifies (freezes) rapidly to produce the skin layer. Since the core remains in the molten state, plastic follows through the core to complete mold filling. Typically, the cavity is filled to 95%~98% during injection. Then the molding process is switched over to the packing phase.
Even as the cavity is filled, the molten plastic begins to cool. Since the cooling plastic contracts or shrinks, it gives rise to defects such as sink marks, voids, and dimensional instabilities. To compensate for shrinkage, addition plastic is forced into the cavity. Once the cavity is packed, pressure applied to the melt prevents molten plastic inside the cavity from back flowing out through the gate. The pressure must be applied until the gate solidifies. The process can be divided into two steps (packing and holding) or may be encompassed in one step(holding or second stage). During packing, melt forced into the cavity by the packing pressure compensates for shrinkage. With holding, the pressure merely prevents back flow of the polymer malt.
After the holding stage is completed, the cooling phase starts. During, the part is held in the mold for specified period. The duration of the cooling phase depends primarily on the material properties and the part thickness. Typically, the part temperature must cool below the material’s ejection temperature. While cooling the part, the machine plasticates melt for the next cycle.
The polymer is subjected to shearing action as well as the condition of the energy from the heater bands. Once the short is made, plastication ceases. This should occur immediately before the end of the cooling phase. Then the mold opens and the part is ejected.
When polymers are fabricated into useful articles they are referred to as plastics, rubbers, and fibers. Some polymers, for example, cotton and wool, occur naturally, but the great majority of commercial products are synthetic in origin. A list of the names of the better known materials would include Bakelite, Dacron, Nylon, Celanese, Orlon, and Styron. Previous to 1930 the use of synthetic polymers was not widespread. However, they should not be classified as new materials for many of them were known in the latter half of the nineteenth century. The failure to develop them during this period was due, in part, to a lack of understanding of their properties, in particular, the problem of the structure of polymers
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湖南涉外经济学院本科生毕业论文（设计）
was the subject of much fruitless controversy.
Two events of the twentieth century catapulted polymers into a position of worldwide importance. The first of these was the successful commercial production of the plastic now known as Bakelite. Its industrial usefulness was demonstrated in1912 and in the next succeeding years. Today Bakelite is high on the list of important synthetic products. Before 1912 materials made from cellulose were available, but their manufacture never provided the incentive for new work in the polymer field such as occurred after the advent of Bakelite. The second event was concerned with fundamental studies of the nature polymers by Staudinger in Europe and by Carohers, who worked with the Du Pont company in Delaware. A greater part of the studies were made during the 1920’s. Staudinger’s work was primarily fundamental. Carother’s achievements led to the development of our present huge plastics industry by causing an awakening of interest in polymer chemistry, an interest which is still strongly apparent today.
The Nature of Thermodynamics
Thermodynamics is one of the most important areas of engineering science used to explain how most things work, why some things do not the way that they were intended, and why others things just cannot possibly work at all. It is a key part of the science engineers use to design automotive engines, heat pumps, rocket motors, power stations, gas turbines, air conditioners, super-conducting transmission lines, solar heating systems, etc.
Thermodynamics centers about the notions of energy, the idea that energy is conserved is the first low of thermodynamics. It is starting point for the science of thermodynamics is entropy; entropy provides a means for determining if a process is possible.
This idea is the basis for the second low of thermodynamics. It also provides the basis for an engineering analysis in which one calculates the maximum amount of useful that can be obtained from a given energy source, or the minimum amount of power input required to do a certain task.
A clear understanding of the ideas of entropy is essential for one who needs to use thermodynamics in engineering analysis. Scientists are interested in using thermodynamics to predict and relate the properties of matter; engineers are interested in using this data, together with the basic ideas of energy conservation and entropy production, to analyze the behavior of complex technological systems.
There is an example of the sort of system of interest to engineers, a large central power stations. In this particular plant the energy source is petroleum in one of several forms, or
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