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中國(guó)地質(zhì)大學(xué)長(zhǎng)城學(xué)院 本科畢業(yè)設(shè)計(jì)外文資料翻譯 系 別: 工程技術(shù)系 專 業(yè): 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 姓 名: 黃杰 學(xué) 號(hào): 05211526 2015年 4月 18日 夾具的發(fā)展及其趨勢(shì)分析 近些年來(lái),隨著數(shù)控機(jī)床、加工中心、柔性制造單元、柔性制造系統(tǒng)等現(xiàn)代化加工設(shè)備的廣泛應(yīng)用,使傳統(tǒng)的機(jī)械加工的制造方法發(fā) 生了重大變革,夾具的功能逐漸轉(zhuǎn)變?yōu)檠b夾、定位。而數(shù)字化的設(shè)備加工功能的擴(kuò)大化,給今后夾具的快速定位、快速裝夾提出了更高地要求。 夾具 ,就是在機(jī)械的加工和制造的過(guò)程之中 ,用來(lái)定位和固定加工器件的一種機(jī)械設(shè)備 ,夾具在整個(gè)加工過(guò)程中占有極其重要的地位 ,他不但可以準(zhǔn)確地固定加工器具 ,還能對(duì)器件的施工和檢測(cè)帶來(lái)諸多的方便。 機(jī)床夾具 是一種具有較高柔性的先進(jìn)工藝裝備 ,主要適用于數(shù)控機(jī)床、加工中心以及柔性加工單元和柔性制造系統(tǒng) ,不僅保持了組合夾具的傳統(tǒng)優(yōu)勢(shì) ,而且更符合現(xiàn)代加工理念。它是由一套預(yù)先制造好的各種不同形狀、不同規(guī) 格尺寸的標(biāo)準(zhǔn)元件組裝而成。 在機(jī)械加工制造過(guò)程中,用來(lái)固定加工對(duì)象,使其占有正確的位置,以便接受施工、檢測(cè)的裝置,都可統(tǒng)稱為“夾具”。 鉆床夾具從產(chǎn)生到現(xiàn)在,大約可以分為三個(gè)階段:第一個(gè)階段主要表現(xiàn)在夾具與人的結(jié)合上,這時(shí)夾具主要是作為人的單純的輔助工具,使加工過(guò)程加速完成和趨于完善;第二個(gè)階段,夾具成為人與機(jī)床之間的橋梁,夾具的功能發(fā)生變化,它主要用于工件的定位和夾緊。人們?cè)絹?lái)越認(rèn)識(shí)到夾具與操作人員改進(jìn)工作及機(jī)床性能的提高有著密切的關(guān)系,所以對(duì)夾具引起了重視;第三階段表現(xiàn)為夾具與機(jī)床的結(jié)合,夾具作為機(jī)床的 一部分,成為機(jī)械加工中不可缺少的工藝裝備。 1 國(guó)內(nèi)外發(fā)展趨勢(shì) 夾具是機(jī)械加工不可缺少的部件,在機(jī)床技術(shù)高速、高效、精密、復(fù)合、智能、環(huán)保方向發(fā)展的帶動(dòng)下,夾具技術(shù)正朝著高精、高效、模塊、組合、通用、經(jīng)濟(jì)方向發(fā)展。 1.1 高精度 隨著機(jī)床加工精度的提高,為了降低定位誤差,提高加工精度對(duì)夾具的制造精度要求,更高精度夾具的定位孔距精度高達(dá)正負(fù) 5 微米,夾具支撐面的垂直度達(dá)到 0.01mm/300mm,平行度高達(dá) 0.01mm/500mm。德國(guó) demmeler 公司制造的長(zhǎng) 4m、寬 2m 的孔系列組合焊接夾具平臺(tái),其高 誤差為正負(fù) 0.03mm,精度平口鉗的平行度和垂直度在 5 微米以內(nèi),夾具重復(fù)安裝的定位精度高達(dá) 25 微米。機(jī)床精度已提高到微米級(jí)。 1.2 高效率 為了提高機(jī)床的生產(chǎn)效率,雙面、四面和多件裝夾的夾具產(chǎn)品越來(lái)越多。新型的電控永磁夾具,夾緊和松開(kāi)工件只要 1.2 秒,夾具機(jī)構(gòu)簡(jiǎn)化,為機(jī)床進(jìn)行多 工位、多面和多件加工創(chuàng)造了條件。為了縮短在機(jī)床上安裝與調(diào)整夾具的時(shí)間,瑞典 3R 夾具僅用一分鐘,即可完成線切割機(jī)床夾具的安裝與校正,采用美國(guó) jergens 公司的球鎖裝夾系統(tǒng),一分鐘就能將夾具定位和鎖緊在機(jī)床工作臺(tái)上。 1.3 模塊化 組合夾具元件模塊化是實(shí)現(xiàn)組合化的基礎(chǔ)。省工、省時(shí)、節(jié)材、節(jié)能,體現(xiàn)在各種先進(jìn)夾具系統(tǒng)的創(chuàng)新之中。模塊化設(shè)計(jì)為夾具的計(jì)算機(jī)輔助設(shè)計(jì)與組裝打下基礎(chǔ)。應(yīng)用 CAD技術(shù),可建立元件庫(kù)、典型夾具庫(kù)、標(biāo)準(zhǔn)和用戶使用檔案庫(kù),進(jìn)行夾具優(yōu)化設(shè)計(jì)。組合夾具分會(huì)與華中科技大學(xué)合作,正在著手創(chuàng)建夾具專業(yè)技術(shù)網(wǎng)站,為夾具行業(yè)提供信息交流、夾具產(chǎn)品咨詢與開(kāi)發(fā)的公共平臺(tái),爭(zhēng)取實(shí)現(xiàn)夾具設(shè)計(jì)與服務(wù)的通用化、遠(yuǎn)程信息化和經(jīng)營(yíng)電子商務(wù)化。 1.4 通用化 經(jīng)濟(jì)夾具的通用性直接影響其經(jīng)濟(jì)性。夾具系統(tǒng)的可重組性、可重構(gòu)性及可 擴(kuò)展性功能強(qiáng),應(yīng)用范圍廣,通用性好,夾具利用率高。德國(guó) demmeler 公司的孔系列組合焊接夾具,僅用品種、規(guī)格很少的配套元件即能組裝成多種多樣的焊接夾具。元件功能強(qiáng),使得夾具的通用性好,元件少而精,配套的費(fèi)用低,經(jīng)濟(jì)實(shí)用才有推廣應(yīng)用的價(jià)值。 隨著我國(guó)經(jīng)濟(jì)的高速發(fā)展,社會(huì)對(duì)機(jī)械產(chǎn)品需求多樣化的趨勢(shì)也越來(lái)越明顯,為此,制造技術(shù)的研究者提出了成組技術(shù)的科學(xué)理論及實(shí)踐方法,它能從根本上解決生產(chǎn)由于品種多,產(chǎn)量小帶來(lái)的矛盾。成組技術(shù)是一門(mén)生產(chǎn)技術(shù)科學(xué),它研究如何識(shí)別和發(fā)掘生產(chǎn)活動(dòng)中有關(guān)事務(wù)的相似性,并對(duì)其進(jìn)行充分利用 。即把相似的問(wèn)題歸類成組,尋求解決這一組問(wèn)題相對(duì)統(tǒng)一的最優(yōu)方案,以取得所期望的經(jīng)濟(jì)效益。成組技術(shù)應(yīng)用與機(jī)械加工方面,乃是將多種零件按其工藝的相似性分類成組,形成零件組。把同一零件組分散得小生產(chǎn)量匯集成較大的成組生產(chǎn)量,從而使小批量生產(chǎn)能獲得近于大批量生產(chǎn)的經(jīng)濟(jì)效果。 2 國(guó)內(nèi)成組技術(shù)應(yīng)用及現(xiàn)狀 2.1 成組技術(shù)的應(yīng)用 目前發(fā)展的成組技術(shù)是應(yīng)用系統(tǒng)工程學(xué)的觀點(diǎn),把中、小批生產(chǎn)中的設(shè)計(jì)制造和管理等方面作為一個(gè)生產(chǎn)系統(tǒng)整體,統(tǒng)一協(xié)調(diào)生產(chǎn)活動(dòng)的各個(gè)方面,全面實(shí)施成組技術(shù)以提高綜合經(jīng)濟(jì)效益。 2.1.1 產(chǎn)品設(shè) 計(jì)方面 由于用成組技術(shù)指導(dǎo)設(shè)計(jì),賦予各類零件以更大的相類似,這就為在制造管理方面實(shí)施成組技術(shù)奠定了良好的基礎(chǔ),使之取得更好地效果。以成組技術(shù)為指導(dǎo)的設(shè)計(jì)合理化和標(biāo)準(zhǔn)化將為實(shí)現(xiàn)計(jì)算機(jī)輔助設(shè)計(jì)奠定良好的基礎(chǔ);為設(shè)計(jì)信息最大程度的重復(fù)使用,加快設(shè)計(jì)速度,節(jié)約時(shí)間作出貢獻(xiàn)。據(jù)統(tǒng)計(jì),當(dāng)設(shè)計(jì)一種新產(chǎn)品時(shí),往往有 3/4 以上的零件設(shè)計(jì)可參考借鑒或直接引用原有產(chǎn)品圖紙,從而減少新設(shè)計(jì)的零件,這不僅可免除設(shè)計(jì)人員的重復(fù)性勞動(dòng),也可以減少工藝準(zhǔn)備工作和降低制造費(fèi)用。 2.1.2 制造工藝方面 成組技術(shù)在制造工藝方面最先得到廣泛 應(yīng)用。開(kāi)始是用于成組工序,即把加工方法、安裝方式和機(jī)床調(diào)整相近的零件歸結(jié)為零件組,設(shè)計(jì)出適用于全組零件加工的成組工序。成組工序允許采用同一設(shè)備和工藝裝置,以及相同或相近的機(jī)床調(diào)整加工全組零件,這樣,只要能按零件組安排生產(chǎn)調(diào)度計(jì)劃,就可以大大減少由于零件品種更換所需要的機(jī)床調(diào)整時(shí)間。此外,由于零件組內(nèi)諸零件的安裝方式和尺寸相近,可設(shè)計(jì)出應(yīng)用于成組工序的公用夾具,只要進(jìn)行少量的調(diào)整或更換某些零件,公用夾具就可適用于全組零件的工序安裝。 2.1.3 生產(chǎn)組織管理方面 成組加工要求將零件按工藝相似性分類形成加工組 ,加工同一加工組有其相應(yīng)的一組機(jī)床設(shè)備。因此,很自然成組生產(chǎn)系統(tǒng)要求按模塊化原理組織生產(chǎn),即采取成組生產(chǎn)單元的生產(chǎn)組織形式。成組技術(shù)是計(jì)算機(jī)輔助管理系統(tǒng)技術(shù)基礎(chǔ)之一。這是因?yàn)檫\(yùn)用成組技術(shù)基本原理將大量信息分類成組,并使之規(guī)格化、標(biāo)準(zhǔn)化,這將有助于建立結(jié)構(gòu)合理的生產(chǎn)系統(tǒng)公用數(shù)據(jù)庫(kù),可大量壓縮信息的儲(chǔ)存量,由于不再是分別針對(duì)一個(gè)工程問(wèn)題和設(shè)計(jì)程序,可使程序設(shè)計(jì)優(yōu)化。 2.2 成組技術(shù)的發(fā)展現(xiàn)狀 成組技術(shù)從 20 世紀(jì) 52 年代提出到如今已經(jīng)歷了近 50 年得發(fā)展和利用。成組技術(shù)作為一門(mén)綜合性的生產(chǎn)技術(shù)科學(xué)是計(jì)算機(jī)輔助設(shè) 計(jì)、計(jì)算機(jī)輔助工藝過(guò)程設(shè)計(jì)、計(jì)算機(jī)輔助制造和柔性制造系統(tǒng)等方面的技術(shù)基礎(chǔ)。我國(guó)早在 20 世紀(jì) 60 年代初就在紡織機(jī)械、飛機(jī)、機(jī)床及工程機(jī)械等機(jī)械制造業(yè)中推廣應(yīng)用成組技術(shù),并見(jiàn)成效。因此,成組技術(shù)受到國(guó)家有關(guān)部、局和工廠企業(yè)、研究所及高等院校的重視。目前,正積極開(kāi)展這一方面的科學(xué)研究、人才培訓(xùn)和推廣應(yīng)用等工作,原機(jī)械部設(shè)計(jì)研究院負(fù)責(zé)組織研制的全國(guó)機(jī)械零件分類編碼系統(tǒng) JLBMI,它將對(duì)我國(guó)推廣應(yīng)用成組技術(shù)起到積極推進(jìn)作用。我國(guó)不少高等工業(yè)院校結(jié)合教學(xué)和科研工作,在成組技術(shù)基本理論及其應(yīng)用方面,如零件分類編碼系統(tǒng)、零 件分類成組方法和計(jì)算機(jī)輔助編碼、分類、工藝設(shè)計(jì)、零件設(shè)計(jì)、生產(chǎn)管理的軟件系統(tǒng)等方面都開(kāi)展了許多研究工作,并取得了不少成果。可以相信,隨著應(yīng)用推廣和科研工作的持續(xù)開(kāi)展,成組技術(shù)對(duì)提高我國(guó)機(jī)械工業(yè)的制造技術(shù)和生產(chǎn)管理水平將日益發(fā)揮其重要的作用。 機(jī)械工業(yè)是國(guó)民經(jīng)濟(jì)的支柱產(chǎn)業(yè),現(xiàn)代機(jī)械制造技術(shù)是機(jī)械工業(yè)賴以生存和發(fā)展的重要保證。機(jī)床夾具隨著科技的發(fā)展使計(jì)算機(jī)技術(shù)、數(shù)控技術(shù)、控制論及系統(tǒng)工程與制造技術(shù)結(jié)合為制造系統(tǒng),形成現(xiàn)代制造工程學(xué)。在機(jī)械制造中,可能會(huì)使用很多專用夾具,這些夾具可以提高勞動(dòng)生產(chǎn)率,提高加工精度, 減少?gòu)U品,可以擴(kuò)大機(jī)床的工藝范圍,改善操作者的勞動(dòng)條件。因此,夾具是機(jī)械制造的一項(xiàng)重要工藝設(shè)備,這也給今后機(jī)床夾具的發(fā)展提出了更高的要求。 Fixture development and trend analysis In recent years, with the numerical control machine tools, machining centers, flexible manufacturing cells, flexible manufacturing systems, the extensive application of modern processing equipment, the traditional method of machining manufacturing has undergone major changes, fixture clamping function gradually changed, positioning . And digital processing functions of the expansion device, to quickly locate the next fixture, to quickly put a higher clamping requirements. Fixture is in the mechanical processing and manufacturing process, used to locate a device and fixed processing machinery and equipment, fixtures in the entire process occupies an extremely important position, he not only can accurately fixed processing equipment, but also construction and testing of devices to bring a lot of convenience. Clamping is a high flexibility of advanced technology and equipment, mainly applied to CNC machine tools, machining centers and flexible manufacturing cells and flexible manufacturing systems, not only to maintain the traditional advantages of modular fixture, and more in line with modern processing concept. It is a good variety of different pre-made shapes, different sizes of standard components assembled. In the mechanical manufacturing process, for a fixed processing object, it occupies the correct position to accept the construction, testing devices, can be collectively referred to as fixture. Drilling jig from generation to now, some can be divided into three stages: the first phase mainly in combination with others on the fixture, then fixture primarily as an aid to the simple people, and accelerate the completion of the process tends to improve ; the second stage, fixtures become a bridge between man and machine tools, fixtures functional changes, it is mainly used for workpiece positioning and clamping. Growing awareness of fixtures and improvements and machine operators to improve the performance of closely related, so attention was given to the fixture; third stage performance of the combination of fixture and machine tools, machine tool fixture as part of a machining indispensable technology and equipment. 1 Domestic and international trends Machining fixture is an indispensable component in the machine tool technology, high-speed, high efficiency, precision, complex, intelligent, environmentally friendly direction, driven by high precision technology is moving fixtures, high efficiency, module, assembly, general economic direction. 1.1 Precision With the improvement of precision machine tools, in order to reduce positioning errors, improve the precision of the manufacture of precision jigs, fixtures more accurate positioning accuracy up to plus or minus 5 micron pitch, vertical surface fixture support up 0.01mm/300mm, parallel up to 0.01mm/500mm. Manufactured in Germany demmeler length 4m, 2m wide hole series combination of welding fixture platform, the high error of plus or minus 0.03mm, precision flat-nose pliers parallelism and perpendicularity of 5 microns or less, repeat the installation fixture positioning accuracy of up to 2 5 microns. Machine tool accuracy has improved to the micron level. 1.2 High efficiency In order to improve the productivity of the machine, double, four and more than clamping fixture products more and more. The new electronically controlled permanent fixture, workpiece clamping and release as long as 1.2 seconds, a fixture agencies to simplify, to machine tools for multi-station, multi-faceted and multi-part processing to create the conditions. In order to shorten the machine time of fixture installation and adjustment, Sweden 3R fixture in just a minute to complete EDM fixture installation and calibration, using the U.S. jergenss ball lock clamping system, one minute will be able to fixture and locking the machine table. 1.3 Modular Modular fixture elements are combined to achieve a combination of the base. Saving labor, time, materials, energy, reflected in a variety of advanced systems of innovation among the fixture. Modular fixture design and assembly of computer-aided design basis. Application of CAD technology to create a component library, a typical fixture libraries, standard and user archive for fixture optimization. Modular fixture branch cooperation with Huazhong University of Science and Technology, is working to create a professional website fixture, fixture industry for the exchange of information, fixtures, product consulting and development of public platforms, and services for fixture design to achieve the universal, long-range information technology and business e-commerce of. 1.4 Universal Economic fixture versatility that directly affect their economy. Fixture system reconfigurability, reconfigurable and scalable feature strong, wide range of applications, common good, high efficiency fixtures. Germany demmelers series combination of welding fixture hole, only species, size small kit that can be assembled into a variety of welding fixtures. Component function is strong, making the fixture common good, concise components, supporting low-cost, economical and practical application have value. With Chinas rapid economic development, social demand for machinery products has become increasingly evident trend of diversification, for manufacturing technology researchers have proposed the scientific theory of group technology and practices, it can fundamentally solve the production As the varieties, yield little to bring the conflict. Group technology is a production technology of science that studies how to identify and explore issues related to production activities similarity, and its full use. That is classified into a group of similar problems, seek solutions to this problem is relatively uniform set of optimal solutions to achieve the desired economic benefits. Application of group technology and mechanical processing, but the variety of parts according to their classification into a process similar to the group, to form parts group. Scattered parts of the same group were pooled into a niche production in groups larger production, so that the small batch production to get close to the economic effects of mass production. 2 Domestic technology and the status of group 2.1 The application of group technology The current development of group technology is the application of systems engineering point of view, the medium and small batch production and management, design and manufacture of a production system as a whole, unified and coordinated all aspects of production activities, the full implementation of group technology to improve the overall economic benefits. 2.1.1 Product design As the use of group technology to guide the design, giving all kinds of parts similar to larger, which is implemented in the manufacturing group technology management has laid a good foundation, so to achieve better results. To group technology to streamline and standardize the design guidance for computer-assisted design to lay a good foundation; to the greatest degree of design information reuse, faster design, saving time to contribute. According to statistics, when designing a new product, they often have 3 / 4 or more parts designed to draw or direct reference to the original reference to drawings, thereby reducing the newly designed parts, which not only eliminates the designers repetitive work, but also preparation can reduce the process and reduce manufacturing costs. 2.1.2 Manufacturing process Group technology in the manufacturing process was first widely used. Start is used for group process, that the processing methods, mounting and adjustment of machine parts due to similar parts groups, designed to fit the whole group into a group of parts machining processes. Into a group of processes using the same equipment and technology to allow devices, and the same or similar processing of the whole group to adjust the machine parts, so long as the parts can be arranged according to production schedules, you can greatly reduce the variety of replacement parts needed to adjust the time machine. In addition, as part of various components within the group and size of installation are similar, can be used to design a common set of processes fixture, as long as a small amount of adjustment or replacement of certain parts, the public can apply to the whole group fixture parts installation process . 2.1.3 Production organization and management Processing requirements will be part of group process is similar to classification by processing group formation, processing the same process group has its corresponding set of machine tool equipment. Therefore, it is natural to group the modular production system required by the principles of organization of production, that production unit to the production of group organization. Group Technology is the foundation of computer-aided management system technology. This is because the basic principles of group technology using large amounts of information will be classified into groups, and make normalization, standardization, which will help to establish structured production system common database of information can be a lot of compressed storage capacity, as no longer respectively, for an engineering and design process, enables the program to design optimization. 2.2 Development of Group Technology Group technology made from the 20th century to the present 52 years has gone through nearly 50 years was the development and use. Group Technology as a comprehensive scientific production technology is computer-aided design, computer aided process design, computer aided manufacturing and flexible manufacturing systems and other aspects of technological base. In the early 20th century, in the early 1960s, textile machinery, aircraft, machine tools and construction machinery and other machinery manufacturing industry in promoting the application of group technology, and effective. Therefore, group technology by the relevant state ministries, departments and factories and enterprises, research institutes and institutions of higher importance. At present, are active in this area of scientific research, personnel training and application, etc., former Ministry of Machinery Design and Research Institute is responsible for organizing the development of national mechanical parts classificatio n and coding system JLBMI, it
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