【溫馨提示】 dwg后綴的文件為CAD圖，可編輯，無水印，高清圖，壓縮包內(nèi)文檔可直接點開預覽，需要原稿請自助充值下載，請見壓縮包內(nèi)的文件及預覽，所見才能所得，請細心查看有疑問可以咨詢QQ：414951605或1304139763
任務書
學生姓名： 學號：
學 院： 專業(yè)：機械電子工程
任務起止時間：
畢業(yè)設(shè)計（論文）題目：
水果套袋機設(shè)計
畢業(yè)設(shè)計工作內(nèi)容：
1、熟悉課題、調(diào)研、收集資料、撰寫開題報告 (第1-2周)
2、方案設(shè)計 (第3-6周)
3、總體設(shè)計、設(shè)計計算 (第7-8周)
4、繪裝配圖及主要零件圖 (第9-13周)
5、撰寫說明書、翻譯資料、準備答辯 (第14-16周)
資料：
1、 龔溎義．機械設(shè)計課程設(shè)計指導書[M]. 北京：高等教育出版社
2、 澲良貴．.紀明鋼. 機械設(shè)計[M]. 北京：高等教育出版社
3、 潘嘹．典型果品機械損傷及其防護機理研究[Ｄ]. 江南大學，碩士論文，２０１１
指導教師意見：
簽名：
年 月 日
系主任意見：
簽名：
年 月 日
教務處制表
外文文獻
Packing machinery development
Our country packs the mechanical profession start in the 20th century 70's, and the 90's intermediate stages obtains the rapid development in the end of the 80's. Has become in the mechanical industry one of 10 big professions, regardless of is the output, in the variety, has all obtained the amazing achievement, packed the industry for our country the fast development to provide the powerful safeguard. At present, our country has become the world packing mechanical industrial production and expends one of great nations.
Current our country food and a packing machinery prominent question is the new product development cycle long, imitates much, innovates few, not only this with designs personnel's state-of-art related, also concerns with the correlation profession development. The international advanced method utilizes the simulation technology, by the computer automatic synthesis three-dimensional model, will pass has occurred production line breakdown data feeds the computer, then will demonstrate the actual operating mode, according to will need to carry on the revision in front of the user, finally will consummate. The packing machinery took one product, its meaning is not merely the product itself material significance, but is includes the form product, the stealth product and extends the product 3 meanings. The form product is refers to packaging machine itself the concrete shape and the basic function; The stealth product is refers to the packaging machine the actual utility which provides to the user; Extends the product is refers to the packaging machine the quality assurance, the use instruction and the post-sale service and so on. Therefore the packaging machine design should include: Market investigation and study, schematic diagram design, structural design, construction drawing design, instruction for use compilation and post-sale service predetermined plan and so on.
The new packing machinery often is machine, the electricity, the gas integration equipment. The full use information product newest achievement, uses air operated separation transmission technologies and so on implementing agency, servo motor-driven, may cause the complete machine the transmission chain to reduce greatly, the structure is greatly the simplification, the work precision and the speed enhances greatly. One of key technologies has used the multi-electrical machinery dragging synchronization control technology. Actually grasps this kind of technology not very difficultly, only is some designs the personnel not to understand the packing machinery this trend of development. If beforehand our country packs the machine design is the imitation, the study stage, then we should have the innovation design consciousness now.
The product design is the plan for the product and its components and subassemblies. To convert the product design into a physical entity, a manufacturing plan is needed. The activity of developing such a plan is called process planning. It is the link between product design and manufacturing. Process planning involves determining the sequence of processing and assembly steps that must be accomplished to make the product. In the present chapter, we examine processing planning and several related topics.
Process Planning
Process planning involves determining the most appropriate manufacturing and assembly processes and the sequence in which they should be accomplished to produce a given part or product according to specifications set forth in the product design documentation. The scope and variety of processes that can be planned are generally limited by the available processing equipment and technological capabilities of the company of plant. Parts that cannot be made internally must be purchased from outside vendors. It should be mentioned that the choice of processes is also limited by the details of the product design. This is a point we will return to later.
Process planning is usually accomplished by manufacturing engineers. The process planner must be familiar with the particular manufacturing processes available in the factory and be able to interpret engineering drawings. Based on the planner’s knowledge, skill, and experience, the processing steps are developed in the most logical sequence to make each part. Following is a list of the many decisions and details usually include within the scope of process planning.
Interpretation of design drawings. The part of product design must be analyzed (materials, dimensions, tolerances, surface finished, etc.) at the start of the process planning procedure.
Process and sequence. The process planner must select which processes are required and their sequence. A brief description of processing steps must be prepared.
Equipment selection. In general, process planners must develop plans that utilize existing equipment in the plant. Otherwise, the component must be purchased, or an investment must be made in new equipment.
Tools, dies, molds, fixtures, and gages. The process must decide what tooling is required for each processing step. The actual design and fabrication of these tools is usually delegated to a tool design department and tool room, or an outside vendor specializing in that type of tool is contacted.
Methods analysis. Workplace layout, small tools, hoists for lifting heavy parts, even in some cases hand and body motions must be specified for manual operations. The industrial engineering department is usually responsible for this area.
Work standards. Work measurement techniques are used to set time standards for each operation.
Cutting tools and cutting conditions. These must be specified for machining operations, often with reference to standard handbook recommendations.
Process planning for parts
For individual parts, the processing sequence is documented on a form called a route sheet. Just as engineering drawings are used to specify the product design, route sheets are used to specify the process plan. They are counterparts, one for product design, the other for manufacturing.
A typical processing sequence to fabricate an individual part consists of: (1) a basic process, (2) secondary processes, (3) operations to enhance physical properties, and (4) finishing operations. A basic process determines the starting geometry of the work parts. Metal casting, plastic molding, and rolling of sheet metal are examples of basic processes. The starting geometry must often be refined by secondary processes, operations that transform the starting geometry (or close to final geometry). The secondary geometry processes that might be used are closely correlated to the basic process that provides the starting geometry. When sand casting is the basic processes, machining operations are generally the second processes. When a rolling mill produces sheet metal, stamping operations such as punching and bending are the secondary processes. When plastic injection molding is the basic process, secondary operations are often unnecessary, because most of the geometric features that would otherwise require machining can be created by the molding operation. Plastic molding and other operation that require no subsequent secondary processing are called net shape processes. Operations that require some but not much secondary processing (usually machining) are referred to as near net shape processes. Some impression die forgings are in this category. These parts can often be shaped in the forging operation (basic processes) so that minimal machining (secondary processing) is required.
Once the geometry has been established, the next step for some parts is to improve their mechanical and physical properties. Operations to enhance properties do not alter the geometry of the part; instead, they alter physical properties. Heat treating operations on metal parts are the most common examples. Similar heating treatments are performed on glass to produce tempered glass. For most manufactured parts, these property-enhancing operations are not required in the processing sequence.
Finally finish operations usually provide a coat on the work parts (or assembly) surface. Examples included electroplating, thin film deposition techniques, and painting. The purpose of the coating is to enhance appearance, change color, or protect the surface from corrosion, abrasion, and so forth. Finishing operations are not required on many parts; for example, plastic molding rarely require finishing. When is required, it is usually the final step in the processing sequence.
Processing Planning for Assemblies
The type of assembly method used for a given product depends on factors such as: (1) the anticipated production quantities; (2) complexity of the assembled product, for example, the number of distinct components; and (3) assembly processes used, for example, mechanical assembly versus welding. For a product that is to be made in relatively small quantities, assembly is usually performed on manual assembly lines. For simple products of a dozen or so components, to be made in large quantities, automated assembly systems are appropriate. In any case, there is a precedence order in which the work must be accomplished. The precedence requirements are sometimes portrayed graphically on a precedence diagram.
Process planning for assembly involves development of assembly instructions, but in more detail .For low production quantities, the entire assembly is completed at a single station. For high production on an assembly line, process planning consists of allocating work elements to the individual stations of the line, a procedure called line balancing. The assembly line routes the work unit to individual stations in the proper order as determined by the line balance solution. As in process planning for individual components, any tools and fixtures required to accomplish an assembly task must be determined, designed, built, and the workstation arrangement must be laid out.
Make or Buy Decision
An important question that arises in process planning is whether a given part should be produced in the company’s own factory or purchased from an outside vendor, and the answer to this question is known as the make or buy decision. If the company does not possess the technological equipment or expertise in the particular manufacturing processes required to make the part, then the answer is obvious: The part must be purchased because there is no internal alternative. However, in many cases, the part could either be made internally using existing equipment, or it could be purchased externally from a vendor that process similar manufacturing capability.
In our discussion of the make or buy decision, it should be recognized at the outset that nearly all manufactures buy their raw materials from supplies. A machine shop purchases its starting bar stock from a metals distributor and its sand castings from a foundry. A plastic molding plant buys its molding compound from a chemical company. A stamping press factory purchases sheet metal either fro a distributor or direct from a rolling mill. Very few companies are vertically integrated in their production operations all the way from raw materials, it seems reasonable to consider purchasing at least some of the parts that would otherwise be produced in its own plant. It is probably appropriate to ask the make or buy question for every component that is used by the company.
There are a number of factors that enter into the make or buy decision. One would think that cost is the most important factor in determining whether to produce the part or purchase it. If an outside vendor is more proficient than the company’s own plant in the manufacturing processes used to make the part, then the internal production cost is likely to be greater than the purchase price even after the vendor has included a profit. However, if the decision to purchase results in idle equipment and labor in the company’s own plant, then the apparent advantage of purchasing the part may be lost. Consider the following example make or Buy Decision.
“十五”period,our country packs the mechanical industrial development to be rapid, in recent years imports the equipment all is domestic cannot make or the manufacture level is far from, may see our disparity from the import to be at. Food security problem whole nation attention. “十一五” period should enhance food security domain the science and technology and the equipment level, the development fast, in accurate appraisal food harms the factor the technology and the equipment, further researches and develops the pathogenic microorganism resistance, cause of disease prevention technologies and the preserve technology and the equipment and so on control. Food and the packing machinery form the profession already for 20 years, is opposite in food packing, a new profession. This 20 years also are the world technological development quickest times, the new technology applies unceasingly in the profession, but the domestic profession foundation is weak, technical and the scientific research lack of strength, its development relative lag, has towed food and the packing industry hind leg to a certain extent. Although overall development quick, but food packing mechanical industrial development is quicker.
the goal is must reduce this space, catches up with the world advanced level for the food industry, for causes the packing great nation to make great strides forward to the packing powerful nation, provides the advanced technical equip, lets import the equipment the role which only plays in the domestic market appropriates lost articles fills a vacancy. This request domestic food and the packing machinery year development speed surpasses 18%, the new product output value rate achieves 25%. On the international packing and food machinery development is take the big customer request as the goal, the impetus correlation machinery development. The big customer request mainly manifests in the below aspect: One, is higher well to the production efficiency request. This may reduce the product the cost, satisfies the date of delivery. The high speed packaging machine request must have the correlation engagement with the first working procedure, does not have to transport the link, including the control engagement, the entire production line must achieve the inverted order according to the production and the packing working procedure arrangement to start, smooth engine off. If Leng Guanzhuang the production line makes something a matter of political line automatically from the plastic raw material to the drink fills installs, the big packing piles buttress completely automatically in seals up in the workshop to carry on. Two, may adapt the product renewal change. The packing machinery must have the very high flexibility and the flexibility, the production line permission the packing material size may change in certain size scope. Because product life cycle far short in useful life of equipment, change product and packing not as for replacement expensive packing production line. Three is the equipment common breakdown rapid elimination. The solution inputs the computer in advance, when the equipment appears the common breakdown may diagnose voluntarily, also may implement the long-distance diagnosis to eliminate the breakdown abreast in row. Four, the request has the automatic diagnosis function. On the one hand may automatic diagnosis packing material thickness, degree of hardness, the counter-tension and so on, feed back through the computer to the manipulator adjusts the movement scope, does not guarantee the resilience. On the other hand, each different product, like shape each different chocolate or the dessert and so on, install to the identical box in, its arrangement is orderly. The production line transmits the product is a disorder, the available probe head scanning, determined the different shape the material position, feeds back again to the different manipulator, it can accurately unmistakably puts in the goods according to the accurate position and the direction in the tray, moreover, removes the manual control quickly the vision and finger weariness. Five, may reduce the environmental pollution as far as possible. The reduction including the noise, the dust pollution, and reduces the reject as far as possible, this point especially is important in the food processing process. Food raw material when processing not only harvests the main product, like corn processing, product besides corn starch, but also has the corn oil, the salad oil, the margarine, the glucose, the corn protein and the feed, as well as the sewage treatment and so on produces the entire process, is the automation. Does not have the reject, not to pollute, other product value has surpassed the corn starch greatly the value.
Along with the science and technology development and the market competition aggravating, the customer demand more and more is also high. This kind of demand manifests in following several aspects: One, enhances the production efficiency, satisfies the date of delivery and reduces the production cost the need, to some products, but also requests the packing machinery and the production machinery links up; Two, is meets the product renewal change need, the packing machinery must have the high flexibility and the flexibility; Three is when the equipment appears the breakdown, the request can carry on the long-distance diagnosis service; Four, favors the environmental protection, the noise, the dust and the reject are few; Five is the equipment purchase investment are as far as possible few, the price must be as far as possible low. Therefore, must certainly in the market investigation and study foundation, the full understanding, analyze the user earnestly the demand, the definite packaging machine should complete the function and each technical specification, draw up the preliminary principle design proposal.
The modern packaging machine design process should include: The market investigation and study, the user demand analysis, the packaging machine function determination, the feasible proof, the formulation design proposal, the user benefit analysis, the plan feasible proof, the schematic diagram design, the structural design, the construction drawing design, the prototypical manufacture (hypothesized manufacture), the technical confirmation and the construction drawing revise, the formulation post-sale service predetermined plan and the long-distance diagnosis plan, the improvement design, the serialized design and so on. .
The market investigation and study is the foundation work which all packaging machines design. Without the market investigation and study, we do all design work all possibly is equal to the zero. The market investigation and study, may according to the policy guidance, the profession supply and demand information, the expert analyze, the profession unfolds clues and so on meeting, technical meeting, found the user the demand information, after and reorganizes the analysis, the definite packaging machine should complete function. In the principle project design process, first must understand fully the related information product, the electronic products function, understood the air operated part the performance, and uses to simplify the mechanical drive system, but also may use the multi-electrical machinery dragging to reduce the mechanical transmission chain. Regarding the essential mechanical drive system, should make the best the modernized design method, in to product functional analysis foundation in, through innovation idea, system model, mechanical analysis, dynamic optimization, thus obtains the best design proposal. The technical design is the principle design structuralization, definite spare part quantity, the shape, the size, the material and so on, the essential components carry on the po