變換齒輪箱體加工的工藝規(guī)程編制及夾具設(shè)計(jì)6含張CAD圖
變換齒輪箱體加工的工藝規(guī)程編制及夾具設(shè)計(jì)6含張CAD圖,變換,齒輪,箱體,加工,工藝,規(guī)程,編制,夾具,設(shè)計(jì),cad
中英文資料
Manufacturing Technology
1.Corporate Reorganization Frenzy
Because of the intense competitive pressure they experienced during the 1980s, American companies began implementing a wide range of initiatives in order to improve profitability, stem the loss of market share in established markets. These initiatives included statistical process control, just-in-time logistics, flexible manufacturing, cross-functional teaming, concurrent engineering, enterprise integration, flattened management, reinvesting the company, reengineering, quality function development, manufacturing resource planning, and so on.
In addition to obvious cost-cutting measures—reducing the blue-and the white-collar work force, pressuring suppliers for lower prices, reducing the rate of wage increases, and installing new technologies to improve the efficiency of operations—companies have introduced a number of programs that are altering traditional managerial relationships.
Three kinds of initiative are of particular importance for pushing companies toward agile business capabilities:
· Distributing decision-making authority, often called employment
· Enterprise integration
· Concurrent operations
Distributing decision-making authority to operational personnel, flattening the managerial hierarchy, creating an open internal information environment, increasing investing in continuous education and training for all personnel, and making customer service and sales everyone’s responsibility are correlated initiatives. Companies are learning that all these initiatives must be implemented, and in a coordinated way, if the impact of any of them is to be lasting.
Over an 18-month period, Texas Instruments’ Defense Systems and Electronics Group moved from 26,000 employees, seven level of management, and $2 billion in revenues to 13,500 employees, every one of whom was in a cross-functional team, supervised by four levels of management while maintaining the same level of revenues and significantly improving earnings.
After the merger of Asea and Brown Boveri, CEO Percy Barnevik fractured the combined companies into more than 1300 quasi-independent business units and 5000 profit centers. At the same time, he cut the combined headquarters staffs from 4000 to 200!
Gould Precision Optics is a seven-employee, family-owned New York State business in which everyone is cross-trained in everyone else’ job, the company’s books are open to all for a monthly review and everyone has a clearly understood stake in the company’s competitiveness.
The positive impact of teaming on a company’s organization and management is fully experienced only when teaming is made comprehensive across the company and coordinated with the delegation of decision-making to operational personnel and the flattening of the managerial hierarchy. Teams need to be cross-functional, have a common goal, and be supported by an open information environment and expanded education and training programs.
The cost of information continues to decrease, and the value of information to productivity improvement, and as a product in its own right, continues to increase. It is hardly surprising, then, that companies are creating seamless information-exchange environments, internally and with suppliers and collaborators. Companies are discovering that integrating the functionally separated divisions of a company, and thereby overcoming the linear business processes that this separation encourages, pays big dividends.
The size of the investments being made in multimedia hardware and software networking technologies make evident the vision that industry holds of its future. The goal is networks that make it possible for people who are distributed worldwide to work together on the same files with simultaneous real-time audio and “video-in-a-window” Macintosh, PC, and low-end workstations are offered, at very small price premiums, with microphones and video cameras built into the keyboard and monitor cases. Network speed and bandwidth are already a reality.
2. What is RP&M
Manufacturing community is facing two important challenging tasks:
(1)substantial reduction of product development time; and （2） improvement on flexibility for manufacturing small batch size products and a variety of types of products. Computer-aided design and manufacturing（CAD and CAM） have significantly improved the traditional production design and manufacturing. However, there are a number of obstacles in true integration of computer-aided design with computer-aided manufacturing for rapid development of new products. Although substantial research has been done in the past for computer-aided design and manufacturing integration, such as feature recognition, CNC programming and process planning, the gap between CAD and CAM remains unfilled in the following aspects:
·rapid creation of 3-D models and prototypes.
·cost-effective production of patterns and moulds with complex surfaces.
To substantially shorten the time for developing patterns, moulds, and prototypes, some manufacturing enterprises have started to use rapid prototyping（RP）methods for complex patterns making and component prototyping. Over the past few years, a variety of new rapid manufacturing technologies, generally called Rapid Prototyping and Manufacturing（RP&M）, have emerged; the technologies developed include Stereolithography（SL）, Selective Laser Sintering（SLS）, Fused Deposition Modeling（FDM）, Laminated Object Manufacturing（LOM）, and Three Dimensional Printing（3-D Printing）. These technologies are capable of directly generating physical objects from CAD databases. They have a common important feature: the prototype part is produced by adding materials rather than removing materials, that is, a part is first modeled by a geometric modeler such as a solid modeler and then is mathematically sectioned（sliced）into a series of parallel cross-section pieces. For each piece, the curing or binding paths are generated. These curing or binding paths are directly used to instruct the machine for producing the part by solidifying or binding a line of material. After a layer is built, a new layer is built on the previous one in the same way. Thus , the model is built layer by layer from the bottom to top. In summary, the rapid prototyping activities consist of two parts: data preparation and model production.
3.The history of RP&M
As usual with invention, one individual’s impatience was the prototyping industry, now barely a decade old. Its father, Charles W Hull, 58 , still works as vice chairman and chief technology officer at the RP company he helped found in 1986, 3D Systems of Valencia, Calif. As an engineer, Hull had always been bothered by the long time it took to make prototype models of plastic. They had to be machined by hand, he recalls. If more than one was needed, generally the case in industry, molds for making plastic prototypes had to be individually machined.
The building blocks of a better system were lying around. Hull had been working for a small company that used ultraviolet lamps to substitute a laser for an ultraviolet lamp. “But taking that insight to a practical machine came slowly,” Hull recalls, and required several years of Edison-style inspiration. （In fact, a prototyping machine based on conventional UV light was developed in 1998 by The Institute of Advanced Manufacturing Technology, Xi’an Jiaotong University, China）.
The results was the first prototyping machine, introduced by 3-D Systems in 1987. It could fabricate small, transparent plastic parts from CAD drawings in hours or at most days. The machine builds the model in layers, from the bottom up. A laser, which causes molecules of a photosensitive liquid resin to polymerize, scans above a vessel filled with the resin. The laser first traces the outline of a layer on the resin’s surface. Next, like an artist shading a panel in a pencil drawing, the beam crisscrosses the whole outlined area to harden it. Then the platform holding the model sinks so the layer is barely awash in liquid resin, the laser goes to work solidifying another layer atop it, and so on. When the translucent object is done, it is raised from the vat, dripping like a mermaid just emerged from the sea.
Hull dubbed the process stereolithography, and it still dominates RP. The resins were, and still are very expensive: A gallon of acrylic blends of photo-curable liquids fetches about $750. But so great is industry’s hunger for prototypes, in an era when the pool of high-paid artisans who can make them by hand is shrinking and time to market is king, that designers were glad to get the first RP machines at any price. 3-D Systems has grown to an $80-million-a-year public company that’s still No.1 in the field by far.
Before long other inventors jumped in. Michael Feygin, an immigrant Russian engineer, hit on the idea of building prototypes from inexpensive slices of paper. His company, Helisys of Torrance, Calif., makes remarkably sturdy objects by a process called laminated-object manufacturing（LOM）.A blue CO2 laser traces each layer by burning, moving like a crazed ice dancer carving a turn here, a straight line there. Successive layers are bonded by adhesive. Helisys, whose machines have modeled auto steering wheels, bumpers, and other shapes that feel like wood to the touch, is a 12-million-a-year public company.
Meanwhile, a group of MIT inventors led by Emanuel Sachs, a slender, unassuming professor of mechanical engineering, chafed at the RP industry’s inability to make prototype, as well as molds and production parts, from ceramics and metal. The early RP machines could make a metal prototype only in a roundabout way. First a plastic model had to be “invested”, or clad in a heat-resistant material such as a ceramic. Then the model was “sacrificed” by melting, just as the ancient Egyptians melted a wax model inside a mold to clear the way for a bronze casting. This leaves a mold suitable for making a metal or plastic prototype.
Why not skip that stage, Sachs asked, and make sturdy parts directly from CAD designs? He and his 30-person shop at MIT have become the leaders in a branch of RP based on the same technique enabling computer printers to produce documents by squirting ink through jets. Instead of ink, MIT’s RP machines squirt a binder on layers of powdered steel, ceramics, or even starch that are spread by rollers.
The machines to which Sachs’ idea has given birth, called 3-D printers, are fairly inexpensive by RP standards, with low-end versions in the $50,000 range. The bigger 3-D printers are only now realizing Sachs’ goal of making commercially usable metal objects and molds directly from CAD designs. Soligen, a Northridge, California, company founded in 1992 by expatriate Israeli engineer Yehoram Uzirl, has developed, under license from MIT, the ink-jet machine Specific Surface employed to make those ceramic filters. On its machines, Soligen also makes ceramic molds, directly from CAD drawings, suitable for casting metal automotive parts that are as strong as those used in commercial products and suitable for testing and small production runs.
Soligen’s process still has limitations. The ceramic molds are made in one piece and can only be used once, since they must be destroyed to get at the part. But Soligen can make lots of molds quickly as needed. Many RP users, eager to go further, want rapidly made molds that can be used over and over for mass production. That would shrink the manufacturing middle some more, bypassing a conventional process in which a long-lasting mold is carefully carved out of a block of high-grade steel with CNC and other machines, then painstakingly finished by hand, a process that can take months.
Quickly made reusable molds, which put RP squarely in rapid-manufacturing territory, have started to appear. When Rubbermaid Office Products of Maryville, Tenn., got an urgent order in 1996 from Staples, the office-products chain, for a small plastic stand that holds sheets of paper vertically, Rubbermaid went to an RP service bureau in Dallas that had a machine made by DTM of Austin, Texas. The ten-year-old company, whose initials stand for “desk top manufacturing,” has developed a sintering process in which loosely compacted plastic are heated by a laser to combine with powdered steel, layer after layer, into a solid mass.
The DTM machine speedily produced a metal mold from which Rubbermaid was able to make more than 30,000 plastic stands for staples, priced at $3. Says Geoff Smith-Moritz, editor of the newsletter Rapid Prototyping Report in San Didgo:“Though not very impressive looking, this product is a pioneer. More and more molds are being made this way.”
In its purest form, rapid manufacturing would eliminate molds: Machines would fabricate products directly from CAD designs. Extrude Hone, a company in Irwin, Pa., is getting ready to market a machine, based on MIT’s ink-jet technology, that will make not only metal molds but also salable metal parts. In Extrude Hone’s machine, powdered steel is hardened with a binder and infiltrated with bronze powder to create a material that is 100% metal.
Powerful new laser may also open doors to direct manufacturing. Such laser systems are being explored at national laboratories such as Sandia and Los Alamos, as well as at the University of Michigan, Penn State, and elsewhere. They may soon be available commercially. In the Sandia system, a 1,000-watt neodymium YAG（yttrium-aluminum-gallium）laser melts powdered materials such as stainless and tool steels, magnetic alloys, nickel-based superalloys, titanium, and tungsten in layers to produce the final part. The process is slow: three hours to make a one-cubic-inch object. But the part is just as metallically dense as one made by conventional means. Sandia vic president Robert J. Eagan says the lab’s researchers hope to see the process used to make replacement parts for the military’s stored nuclear weapons. Commercial interest is high too. Ten companies, including AlliedSignal and Lockheed Martin, are participating in the program. Another 20 companies support research at Penn State, where the goal is to make big objects, such as tank turrets and portions of airplanes, as a single part.
Some experts look to a manufacturing future extensively liberated from today’s noisy, hot routines. Instead of molds and machine tools, these visionaries foresee rows of lasers building parts, 3-D printers fashioning convoluted shaped no CNC machine can carve, and silent ceramic partsmakers replacing the traditional noisy factory din. Many products turned out in future factories could be designed to take advantage of rapid-manufacturing techniques. Implantable drug-release devices, with medicine sealed in, could be made in a single operation, since 3-D printers can make a sandwich-like product.
Manufacturing pioneers find such possibilities intoxicating.“We could have naval ships carry not an inventory of parts but their images digitized on a 3.5-inch diskette, plus a bag of powdered metal and a rapid manufacturing machine,”says 3-M’s Marge Hartfel.Adds Brock Hinzmann, director of technology assessment at SRI International:“In two or three years rapid manufacturing will be on everybody’s lips.”In the meantime, the feats of fast prototyping are giving the factory folks plenty to talk about.
4. Current application areas of RP&M
Although RP&M technologies are still at their early stage, a large number of industrial companies such as Texas Instruments, Inc., Chrysler Corporation, Amp Inc. and Ford Motor Co. have benefited from applying the technologies to improve their product development in the following three aspects.
（1）Design engineering
1)Visualization. Conceptual models are very important in product design. Designers use CAD to generate computer representations of their design concepts. However, no matter how well engineers can interpret blue prints and how excellent CAD images of complex objects are, it is still very difficult to visualize exactly what the actual complex products will look like. Some errors may still escape from the review of engineers and designers. The touch of the physical objects can reveal unanticipated problems and sometimes spark a better design. With RP&M, the prototype of a complex part can be built in short time, therefore engineers can evaluate a design very quickly.
2)Verification and optimization. Improving product quality is always a important issue of manufacturing. With the traditional method, developing of prototypes to validate or optimize a design is often time consuming and costly. In contrast, an RP&M prototype can be produced quickly without substantial tooling and labor cost. Consequently, the verification of design concepts becomes simple: the product quality can be improved within the limited time frame and with affordable cost.
3)Iteration. Just like the automotive industry, manufacturers often put new product models into market. With RPA&M technology, it is possible to go through multiple design iterations within a short time and substantially reduce the model development time.
先進(jìn)制造技術(shù)
1、瘋狂的公司重組
由于在二十世紀(jì)80年代他們經(jīng)歷了強(qiáng)烈的競(jìng)爭(zhēng)壓力，為了提高利潤(rùn)率，阻止市場(chǎng)份額損失，美國(guó)公司開(kāi)始在已建立的市場(chǎng)上實(shí)施大范圍的創(chuàng)新。 這些創(chuàng)新包括統(tǒng)計(jì)程序控制，及時(shí)的后勤學(xué)，靈活的制造業(yè)，交叉功能合作，一致的工程學(xué)，企業(yè)的整合，有序的管理，再投資公司，改建，質(zhì)量功能的開(kāi)發(fā)，制造業(yè)資源計(jì)劃，等等。
除明顯的消減成本的措施之外——減少藍(lán)色和白領(lǐng)力量，迫使供應(yīng)商降低價(jià)格，減少工資的增長(zhǎng)率和安裝新技術(shù)目的是為了提高業(yè)務(wù)運(yùn)營(yíng)的有效性——公司已經(jīng)引進(jìn)了修改傳統(tǒng)管理關(guān)系的一定數(shù)量的程序。
三種類型的創(chuàng)新對(duì)于推動(dòng)公司朝著敏捷企業(yè)能力的方向發(fā)展是特別重要的：
· 分布的政策制定權(quán)威，經(jīng)常稱作就業(yè)
· 企業(yè)的整合
· 同時(shí)的業(yè)務(wù)運(yùn)營(yíng)
對(duì)操作人員來(lái)說(shuō)分布的政策制定權(quán)威，可以使管理階層變得有序，并且能夠創(chuàng)造一個(gè)開(kāi)放的內(nèi)部信息環(huán)境，在連續(xù)的教育和訓(xùn)練下為所有人員增加投資，并且使做顧客服務(wù)和銷(xiāo)售變成每一個(gè)人的責(zé)任，這就是相互有聯(lián)系的創(chuàng)新。公司獲悉如果他們中的任何一個(gè)的沖擊是持久的，那么他們就必須使用一種協(xié)調(diào)的方式來(lái)實(shí)施所有這些創(chuàng)新。
在18個(gè)月的期間里，德洲儀器防御系統(tǒng)和電子小組從26,000雇員，及七成的管理水平和二十億美元的收入中轉(zhuǎn)變成了13,500名雇員，并且他們中的每一個(gè)人都是這具有交叉架功能團(tuán)隊(duì)中的一員，當(dāng)維護(hù)同樣水平的收支和極大地改進(jìn)收入時(shí)，由四成水平的管理人員進(jìn)行監(jiān)督。
在瑞典通用電氣公司和法瑞公司合并之后， Percy Barnevik這位首席執(zhí)行官打破了公司間的超過(guò)1300個(gè)類似獨(dú)立營(yíng)業(yè)單位和5000個(gè)利潤(rùn)中心的這種聯(lián)系。 同時(shí)，他將聯(lián)合的總部職員從4000減少了到200!
有精確光學(xué)的古爾德人占七成雇員，他們的家族擁有紐約州事務(wù)，這些事物對(duì)每個(gè)人來(lái)說(shuō)都要在所有的其他別的工作崗位上被訓(xùn)練，公司的書(shū)對(duì)所有的每個(gè)月的回顧及檢查都是開(kāi)放的，并且大家清楚地了解在公司的競(jìng)爭(zhēng)性中的獎(jiǎng)金。
只有當(dāng)合作成為全面橫跨公司，并且對(duì)操作人員和有序的管理階層來(lái)說(shuō)，能夠協(xié)調(diào)以制定政策的代表團(tuán)時(shí)，合作對(duì)公司的組織和管理的積極影響才能被充分地體驗(yàn)。 團(tuán)隊(duì)需要互補(bǔ)功能，需要有一個(gè)共同的目標(biāo)，一個(gè)開(kāi)放的信息環(huán)境和擴(kuò)大的教育及訓(xùn)練節(jié)目的支持。
信息的成本繼續(xù)在下降，隨之，作為本身就是一種產(chǎn)品的信息，隨著生產(chǎn)率的提高它的價(jià)值卻繼續(xù)地增加。這幾乎一點(diǎn)都不驚奇，然后，公司將在內(nèi)部和在供應(yīng)商與合作者之間創(chuàng)造出無(wú)縫信息交換環(huán)境。公司正在發(fā)現(xiàn)整合那些在功能上相互獨(dú)立的一個(gè)公司的各個(gè)部門(mén)，并且從而克服這種鼓勵(lì)分離的線性業(yè)務(wù)流程，進(jìn)而支付大股息。
在多媒體硬件和軟件網(wǎng)絡(luò)技術(shù)中投資額的大小已經(jīng)形成了，并且使公司的這種在未來(lái)產(chǎn)業(yè)中形成的愿景變得很明顯。目標(biāo)就是使網(wǎng)絡(luò)成為可能：隨著話筒和攝像機(jī)被裝入鍵盤(pán)和顯示器盒，則那些分布在全世界的人們可以同時(shí)打開(kāi)一個(gè)文件并且可以進(jìn)行同時(shí)實(shí)時(shí)音頻，及“在窗口錄影” Macintosh，個(gè)人計(jì)算機(jī)和以非常小的價(jià)格保險(xiǎn)費(fèi)提供低終端的工作站。 網(wǎng)絡(luò)速度和帶寬已經(jīng)成為了現(xiàn)實(shí)。
2、RP&M是什么了呢？
制造業(yè)團(tuán)體面臨著兩項(xiàng)重要的富有挑戰(zhàn)性的任務(wù)：
(1) 大量的減少了產(chǎn)品的開(kāi)發(fā)時(shí)間； (2)提高了制造小批量產(chǎn)品和各種各樣類型的產(chǎn)品的制造業(yè)的靈活性。 計(jì)算機(jī)輔助設(shè)計(jì)和制造業(yè)(CAD和CAM)顯著改進(jìn)了傳統(tǒng)生產(chǎn)設(shè)計(jì)和制造業(yè)。然而，為新產(chǎn)品的迅速發(fā)展，對(duì)于確切地整合計(jì)算機(jī)輔助設(shè)計(jì)與計(jì)算機(jī)輔助生產(chǎn)，有許多的障礙。盡管在過(guò)去對(duì)計(jì)算機(jī)輔助設(shè)計(jì)和制造業(yè)整合進(jìn)行了大量的研究，例如特征識(shí)別，CNC編程和處理計(jì)劃，CAD和CAM之間的空白在以下方面依然是未填充：
·三維模型和原型的迅速創(chuàng)作。
·有復(fù)雜表面的樣式和模子的有效成本的生產(chǎn)。
極大地縮短了為開(kāi)發(fā)樣式，模具和原型的時(shí)間，一些制造業(yè)企業(yè)開(kāi)始使用快速的原型機(jī)制造方法用于制作復(fù)雜的樣式做和原型機(jī)制造組件。在過(guò)去幾年里，各種各樣的新的快速的制造業(yè)技術(shù)，一般被稱作快速原型制造和制造業(yè)（RP&M）已經(jīng)形成了；被開(kāi)發(fā)的技術(shù)包括立體平版印刷術(shù)(SL)，有選擇性的激光焊接(SLS)，被熔化的沉積物塑造(FDM)，分層物體的制造業(yè)(LOM)和三維空間打印(三維打印)。這些技術(shù)具有直接地從CAD數(shù)據(jù)庫(kù)中生成實(shí)體的能力。他們有一個(gè)共同的重要特點(diǎn)：原型機(jī)零件是通過(guò)增加材料而不是取消材料來(lái)生產(chǎn)的，即，零件首先要被制成幾何學(xué)的模型，然后被劃分成(切成)一系列的平行的短剖面片斷。對(duì)于每個(gè)片斷，都要就行紅外線固化或是裝訂路徑。這些紅外線固化或裝訂路徑通過(guò)凝固或是綁定一系列的材料直接地被用來(lái)指導(dǎo)生產(chǎn)零部件的機(jī)器。在層數(shù)被建立之后，新的層數(shù)將會(huì)以相同的方式早先被建立。 因此，模型是被從底部到頂端一層一層地建立。總之，快速的原型機(jī)制作活動(dòng)包括兩部分：數(shù)據(jù)準(zhǔn)備和模型生產(chǎn)。
3、快速原型制造和制造業(yè)（RP&M）的歷史
像平常一樣的發(fā)明，一個(gè)人的不耐煩是原型制造產(chǎn)業(yè)，現(xiàn)在僅僅十年的樣子。其父親，查爾斯瓦特赫爾，58歲，仍是工程副委員長(zhǎng)和技術(shù)總監(jiān)，在1986年幫助他發(fā)現(xiàn)了RP公司，加利福尼亞3D巴倫西亞系統(tǒng)。 作為工程師，赫爾很懊惱因?yàn)樗撕荛L(zhǎng)時(shí)間用塑料來(lái)制作原型機(jī)的模型。他們必須親自加工，他回憶說(shuō)。 如果有一個(gè)以上的需要，一般情況下在企業(yè)里的情況是，做塑料原型的模子必須單獨(dú)地用機(jī)器制造。
在四周矗立一個(gè)更好的系統(tǒng)的建筑群。赫爾一直致力于為一家小公司而工作，這家小公司過(guò)去常常使用紫外光燈替代紫外激光燈?！暗沁@種做法對(duì)于了解一個(gè)實(shí)用機(jī)器變得很緩慢，”赫爾回憶道，并且需要幾年愛(ài)迪生式的啟發(fā)。(實(shí)際上，在1998年基于常規(guī)紫外光的原型制造機(jī)已經(jīng)形成了，這是由中國(guó)西安交通大學(xué)先進(jìn)的制造業(yè)技術(shù)研究院主導(dǎo)的。)
結(jié)果是第一個(gè)原型制造機(jī)器，在1987年引進(jìn)了三維系統(tǒng)。 它可以示在幾小時(shí)或好幾天的時(shí)間里用CAD畫(huà)圖，制造出小的、透明的塑料部分。機(jī)器在層上建立模型，從下到上。激光，可以造成光敏液體樹(shù)脂分子聚合，并且在充滿樹(shù)脂的容器之上掃描。 接著，它可以像一個(gè)藝術(shù)家一樣用素描在面板上留下底紋，射線在整個(gè)大致的區(qū)域交叉往來(lái)以使它硬化。然后讓這個(gè)平臺(tái)將模型沉下去，因此有著層數(shù)的平臺(tái)是幾乎不可能充滿液體樹(shù)脂的，激光繼續(xù)起作用在它上面去另一層工變硬，等等。當(dāng)半透亮的物體形成時(shí)，水滴就像是從海底涌現(xiàn)出來(lái)的美人魚(yú)一樣。
赫爾復(fù)制了立體平版印刷術(shù)的過(guò)程，并且它仍然控制著RP。樹(shù)脂仍然是非常昂貴的：一加侖的丙烯酸酯用可醫(yī)治的液體的混合可售得大約750美元。但更重要的是企業(yè)對(duì)原型制造機(jī)的渴求，在這樣一個(gè)時(shí)代里，有著大量的高薪酬的能工巧匠們正在減少，上市的時(shí)間是很寶貴，設(shè)計(jì)師們很高興得到第一個(gè)RP機(jī)器的以所有價(jià)格。 三維系統(tǒng)已經(jīng)成長(zhǎng)為每年都有八千萬(wàn)股票
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