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wastes S.E. Saratov Federation November 25 Decembe influence posites produced with PVB. The characterization involved: elongation under rupture, water absorption, tensile strength and elastic provides a means to decrease environmental contamina- tion. Flat glass processing involves the generation of the lack of technological processes oriented towards its glass processing, usually produce both types of the aforementioned wastes or are located close by, it was applications. The best scheme is that for plants produc- ing both wastes, for example in the manufacturing of di?erent profiled rods, characterized with high mechan- ical properties stable in conditions of humid atmosphere and temperature changes. However, the presence of * Corresponding author. Tel.: +52 844 438 9600; fax: +52 844 438 9610. E-mail address: alexande@saltillo.cinvestav.mx (A.V. Gorokhovsky). Waste Management 25 0956-053X/$ - see front matter C211 2004 Elsevier Ltd. All rights reserved. wastes, like scrap of glass mirrors as well as strips of poly (vinyl) butiral film (PVB), from the manufacture of automobile windscreens (Garner, 1996) and safety architectural glass (Lievens, 1995). Clean PVB waste can be recycled on the basis of well-known technological processes; however, about 5–20% of this waste contains contamination, which precludes its recycling. Moreover, in developing countries there is little e?orts or possibility for the recycling of this type of waste. Additionally, waste from glass mirror production (scrap or mirrors not meeting standards) has to be disposed because of of interest to investigate the possibility of producing glass-polymer composites based on the complex utiliza- tion of such wastes that are inapplicable for recycling. The production of composites based on PVB wastes is especially attractive in developing countries, where their collection as well as transportation into the plants spe- cialized in PVB recycling is economically unprofitable. The high adhesion properties of the PBV to the soda- lime-silicate glass surface (Garner, 1996; Gopal et al., 1997) make the composite, based on PVB waste and milled glass, a promising material useful for di?erent modulus tests. The results showed that the composite containing 10 wt% of filler powder had the best properties among the com- positions studied. The influence of the time of exposure in humid atmosphere on the composite properties was investigated. It was found that the admixture of PVB iso-propanol solution to the scrap of glass mirrors during milling provided stabilization of the properties of the composites produced. C211 2004 Elsevier Ltd. All rights reserved. 1. Introduction The use of industrial wastes to produce composite materials is one of the current problems of industry; this utilization (Foss, 1997). The amounts of such waste can reach 10–15% of commercial production in di?erent plants. Taking into account that the plants oriented to flat Composite materials based on A.V. Gorokhovsky a, * , J.I. Escalante-Garcia L.P. Nikulina b , a Department of Engineering Ceramics, CINVESTAV Unidad Saltillo, Carr. b Department of Chemical Technology, Technological Institute of Russian Accepted 3 Available online Abstract Glass mirrors scrap and poly (vinyl) butiral waste (PVB) obtained rials to produce composites. The emphasis was on studying the doi:10.1016/j.wasman.2004.11.007 of flat glass processing a , G.Yu. Gashnikova b , Artemenko b Saltillo-Monterrey km13, AP 663, Saltillo, CP25000 Coahuila, Mexico State Technical University, Pl. Svobody 17, Engels 413100, 2004 r 2004 from flat glass processing plants were investigated as raw mate- of milled glass mirror waste contents on properties of com- (2005) 733–736 metal particles on the glass surface of milled glass mirror scrap as well as the use of PVB waste could negatively influence the exploitation properties and thus must be investigated. 2. Methodology of glass powder: (a) ‘‘fresh’’ dry milled, (b) dry milled and exposed to a humid atmosphere for a month, (c) milled with PVB alcohol solution and exposed to a hu- mid atmosphere for a month. The average tensile mechanical strength of the com- posite articles was measured by testing 18 specimens of each system using the ER-5046-5 Russian equipment. The Young modulus was measured following the tested properties decreased only during the first two months of exposure and then stabilized. The same e?ect Table 1 The properties of composites obtained by extrusion of samples made of separa (wt%) 2.7 7.4 734 A.V. Gorokhovsky et al. / Waste Management 25 (2005) 733–736 Properties Contents of glass powder 013 Young module (MPa) 2.3 2.5 Tensile strength (MPa) 6.8 5.2 Wastes of Saratovsteklo Inc. (Russia) were used for the experiments. The glass used to produce mirrors had the following chemical composition (wt%): 73.1 SiO 2 ; 1.1 Al 2 O 3 ; 8.6 CaO; 3.6 MgO; 13.6 Na 2 O. The mirror coating was formed by vacuum sputtering of stainless steel. PVB waste was obtained from the poly- mer film B-17 produced by Monsanto. In Series 1 of the experiments, the filler was produced by dry ball milling of glass mirror scrap, in jars of alu- mina with balls of alumina, to reach a surface area of 4000 ± 100 cm 2 /g (controlled by LHM-8MD Russian equipment). The ground glass was then added to PVB waste molten at 115 C176C, the latter was previously ad- mixed with 0.5 wt% of poly (ethyl) silane (PES-5, Volzh- skii, Russia) to promote the blending of components and increase homogeneity of composition. The ratio of glass powder and molten PVB was varied in the range of 1–30 wt%. The mixtures obtained were used to pro- duce films by quenching, as well as rods by extrusion. It is well known that water vapor adsorption onto the surface of soda-lime-silicate glasses influences their adhesion to polymers (Kawaguchi and Pearson, 2003; Gu et al., 2000; Radhakrishnan and Unde, 1999). It has been shown (Soshko et al., 1989) that the admixtures of some organic polymers into the glass scrap during milling promoted the modification of the glass surface by the products of their thermo-mechanical destruction (Dhaliwal and Hay, 2000). For this reason, an addi- tional batch of Series 2 was prepared using composites made from the resulting material obtained after joint ball milling of glass mirrors scrap admixed with PVB waste dissolved at room temperature in iso-propanol (15% solution); the weight ratio of glass scrap and PVB–alcohol solution was 0.05. It was expected that the glass powder thus obtained would have enhanced hydrophobic properties and improved adhesion to PVB. To characterize such surface modification, the ob- tained fillers were investigated by TGA/DTGA (Perkin Elmer/Seiko Instruments, Japan) for the following types Relative elongation under rupture (%) 318 345 288 was displayed by the results presented in Table 2, show- ing the properties of composites obtained with the ‘‘fresh’’ and ‘‘old’’ (exposed in air for a month) glass powder. Such reduction in the exploitation properties observed, in agreement with published results (Keller and Mortelmans, 1999), can be attributed to the pro- cesses taking place on the surface of glass filler before the production of composites: adsorption (condensa- tion) of water vapor from the atmosphere, leaching of sodium ions, and crystallization of Na 2 CO 3 and NaH- te dry milling of glass 51015202530 2.9 4.3 3.8 2.7 2.5 2.3 7.9 11.2 8.4 8.5 7.0 5.4 E1875-00e1 ASTM standard using UZIS equipment (LETI, Russia). Taking into account the influence of environmental factors on the properties of materials produced, speci- mens of the two composites, prepared with the fillers of Series 1 and 2, were exposed for three months at 25 C176C in air (40% humidity); and the same mechanical tests, as previously described, were repeated to determine the range of variation in the main characteristics during exploitation. 3. Results and discussion The main characteristics of composites with di?erent contents of glass powder for Series 1, measured immedi- ately after their production, are presented in Table 1. The introduction of 1–10 wt% of glass powder into the matrix of PVB waste increased the mechanical strength of the composite (by 1.6 times) and decreased its relative elongation under the rupture (by 1.3 times). Further in- crease of glass powder contents decreased the exploita- tion properties. The influence of exposure to a humid atmosphere on the exploitation properties of the composite, made from Series 1 with 10 wt% of glass powder (highest mechani- cal properties), is presented in Figs. 1 and 2. All the 271 237 328 295 286 142 CO 3 as a result of the sodium ions interaction with dis- solved CO 2 . The presence of these crystals and adsorbed water onto the surface of glass filler decreased adhesion with PVB. At the same time, modification of the glass powder surface during the milling of glass mirrors scrap with PVB alcohol solution (Series 2) can increase the hydrophobic properties of the glass powder and stabilize the structure of the composite. A comparison of proper- ties for composites from Series 1 and 2 is shown in Figs. 1 and 2; an improvement and increased stability of prop- glass mirrors scrap with PVB waste, dissolved at room temperature in iso-propanol (15% solution), were ap- Temperature,?C 35 30 Characteristics 25 Relative elongation under a rupture 20 15 Tensile strength 10 5 Young modulus 0 0 50 100 150 Exposure, days Fig. 1. Influence of exposure to humid atmosphere on properties of composites produced with powder obtained from Series 1 (continuous lines) and Series 2 (dashed lines): relative elongation under a rupture (%·10 C01 ), tensile strength (MPa), Young modulus (MPa). A.V. Gorokhovsky et al. / Waste Management erties of the composite produced in Series 2 can be noted. 3 2.5 Sweling, wt.% 2 1.5 1 0.5 0 Table 2 Properties of composites, made from Series 1 and with 10 wt% of glass powder, produced immediately after the milling and after one month of glass powder storage in air Property Type of glass powder applied One month after milling ‘‘Fresh’’ powder Young modulus (MPa) 3.8 4.3 Tensile strength (MPa) 8.2 11.2 Relative elongation before the rupture (%) 281 237 0 50 100 150 Exposure, days Fig. 2. Influence of exposure in humid atmosphere (dashed lines) and water (continuous lines) on weight of composite rods produced from Series 1 (d) and Series 2 (s). The obtained data of DTGA (Fig. 3) indicates that the ‘‘old’’ glass filler, in comparison with the ‘‘fresh’’ fil- ler obtained by dry ball milling, is characterized by the additional intensive peak at 350–420 C176C, related to the desorption of chemically adsorbed water (Hench, 1978; Gorokhovsky, 1988). At the same time, this peak is ab- sent for the filler milled jointly with the PVB solution in iso-propanol; moreover, the quantity of condensed water is much less. The additional peaks in the thermo- gram of this filler are related to the melting and thermal decomposition of PVB (Dhaliwal and Hay, 2000). Thus, it is possible to propose that the e?ect of stabilization of the mechanical properties, obtained for the composite produced on the base of glass powder with modified sur- face (Series 2), was achieved due to a decreased adsorp- tion of water vapor. The composite rods of di?erent profiles, produced by extrusion of the batch based on the PVB wastes and glassy filler (10 wt%), obtained by joint ball milling of Fig. 3. DTGA data obtained for di?erent types of filler: A – ‘‘fresh’’ dry milled, B – ‘‘old’’ dry milled, C – ‘‘old’’ milled with PVB alcohol solution. 1, 2 – desorption of condensed water, 3 – desorption of chemically adsorbed water, 4 – melting of PVB; 5, 6 – thermal decomposition of PVB and its derivatives formed by milling. 0 10 20 30 40 50 60 50 100 150 200 250 300 350 400 450 500 DTG, microg/min 1 2 3 4 5 6 1 1 2 A B C 25 (2005) 733–736 735 plied in Salavatsteklo Co. (Salavat, Russia) to manufac- ture the double glazing blocks, as well as bases for the storage and transportation of glass sheets of high thick- ness (weight). 4. Conclusions Composite materials with attractive exploitation properties can be produced on the basis of typical wastes of flat glass processing: poly (vinyl) butiral ribbons and glass mirror scrap. The contents about of 10 wt% of glass powder results in composites with high and stable mechanical properties. The introduction of PVB alco- hol solution resulted in the stabilization of properties of the composites in the case of exposure to humid atmospheres. References Dhaliwal, A.K., Hay, J.N., 2000. The characterization of polyvinyl butyral by thermal analysis. Thermochimica Acta 391 (1–2), 245– 255. Foss, R.V., 1997. Recycling of architectural and automotive glass in Europe. With emphasis on Germany. In: Proc. of 6th International Conference on Architectural and Automotive Glass, Tampere, pp. 44–48. Garner, J., 1996. Automotive glass windscreen design and shaping. Glass Technology 37 (5), 151–152. Gopal, S., Ramchandran, R., Agnihotry, R.S.A., 1997. Polyvinyl butyral based solid polymeric electrolytes: preliminary studies. Solar Energy Materials and Solar Cell 45 (1), 17–25. Gorokhovsky, A.V., 1988. About the nature of surface acidity of multi-component silicate glass. Fizika I Khimiya Stekla (Glass Physics and Chemistry) 14 (5), 739–743. Gu, W., Wu, H.F., Kampe, S.L., Lu, G.-Q., 2000. Volume fraction e?ects on interfacial adhesion strength of glass-fiber-reinforced polymer composite. Materials Science and Engineering A 277 (1– 2), 237–243. Hench, L., 1978. Physical chemistry of glass surfaces. Journal of Non- Crystalline Solids 28 (1), 83–105. Kawaguchi, T., Pearson, R.A., 2003. The e?ect of particle–matrix adhesion on the mechanical behavior of glass filled epoxies. Part 2. A study on fracture toughness. Polymer 44 (15), 4239–4247. Keller, U., Mortelmans, H., 1999. Adhesion in laminated safety glass – what makes it work. In: Proc. of 6th International Conference on Architectural and Automotive Glass, Tampere, pp. 353–356. Lievens, H., 1995. Wide web coating of complex materials. Surface and Coatings Technology 76–77 (Part 2), 744–753. Radhakrishnan, S., Unde, S., 1999. E?ect of substrate preconditioning on charge transport at the phthalocyanine–conducting polymer film interface. Thin Solid Films 347 (1–2), 229–232. Soshko, A.I., Shkarapata, Ya.E., Bolyuk, I.M., 1989. Influence of polymer containing compositions on the e?ectiveness of the mechanical treatment of glass. Glass Ceramics 65 (2), 15–16. 736 A.V. Gorokhovsky et al. / Waste Management 25 (2005) 733–736
本科畢業(yè)論文(設(shè)計)開題報告
論 文 題 目: 小型玻璃磨邊機的結(jié)構(gòu)設(shè)計 學 院: 機械工程學院 專 業(yè) 、班 級: 學 生 姓 名: 指導 教師(職稱):
年 1 月 5 日 填
一、選題依據(jù)1、研究領(lǐng)域
20 世紀 80 年代以來,隨著交通、建筑、旅游等行業(yè)的不斷發(fā)展,人們對玻璃的需求量也越來越多,這就使得玻璃加工行業(yè)得到了快速的發(fā)展,玻璃的產(chǎn)量也迅速提升。
順應(yīng)這一趨勢,論文選題為《小型玻璃磨邊機的結(jié)構(gòu)設(shè)計》,并對此開展對這一領(lǐng)域的研究。
2、論文(設(shè)計)工作的理論意義和應(yīng)用價值
作為玻璃預(yù)處理生產(chǎn)線上的重要工序,玻璃磨邊是玻璃預(yù)處理的關(guān)鍵設(shè)備之一, 主要用于把切割成型的玻璃的邊緣磨制成所需要的形狀,以適應(yīng)不同應(yīng)用環(huán)境的需求。
由于目前數(shù)控機床研發(fā)水平的制約,絕大多數(shù)玻璃生產(chǎn)企業(yè)加工玻璃的精度和效率還有很大的提升空間。西方發(fā)達國家的玻璃生產(chǎn)企業(yè)在已有技術(shù)的基礎(chǔ)上,已經(jīng)開始探索新的玻璃加工工藝,實現(xiàn)玻璃產(chǎn)品的創(chuàng)新,從而有效降低成本,提高效益。玻璃生產(chǎn)加工正朝功能型、裝飾型、環(huán)保型、安全型等方向深入發(fā)展,這也是玻璃加工企業(yè)一直追求的目標。
綜上所訴,論文工作的理論意義和應(yīng)用價值就在于通過對玻璃磨邊機結(jié)構(gòu)的優(yōu)化設(shè)計,根據(jù)磨削原理進行了玻璃磨邊機磨邊系統(tǒng)的力學特性分析,建立了玻璃磨邊機的有限元模型,在力學分析和模態(tài)分析的基礎(chǔ)上完成玻璃磨邊機主機架結(jié)構(gòu)的優(yōu)化設(shè)計,從而提高了機床的整體力學性能和動態(tài)特性。
3、目前研究的概況和發(fā)展趨勢
3.1 國外研究現(xiàn)狀
隨著科技的進步和社會的發(fā)展,國外的玻璃的生產(chǎn)加工已經(jīng)從過去單臺設(shè)備轉(zhuǎn)化成全自動生產(chǎn)線模式,這不僅提高了玻璃的生產(chǎn)加工效率,而且加工出的玻璃精度和質(zhì)量都有了極大的提高。玻璃發(fā)展的如此迅速歸功于玻璃加工設(shè)備的技術(shù)更新,而數(shù)控機床的迅猛發(fā)展離不開一大批專家學者的研究。由于很早就意識到玻璃所具有的獨特的優(yōu)勢,國外的學者花費了大量的人力、物力、財力進行玻璃生產(chǎn)加工設(shè)備的研發(fā), 并取得了大量的科研成果。
美國的諾頓和艾倫合作制訂了選擇砂輪類別和砂輪輪速度的基本原則,提出將砂
輪進行平衡,可以提高磨削效率和精度,并指出在磨削過程中需要實時的修整磨輪使用切削液。美國的奧爾登和英國的格斯特在磨削理論的基礎(chǔ)上對磨削過程中砂輪的選擇、磨削用量設(shè)置、磨削力的大小等問題作了深入的研究??诒镜年P(guān)口八重吉和德國的施勒辛格爾等人在前人研究的基礎(chǔ)上,進一步探討了影響磨削力的各個因素,從而推動了機床檢測技術(shù)的進一步發(fā)展。在機床設(shè)計分析方面,國外具有先進的玻璃生產(chǎn)設(shè)備研發(fā)基礎(chǔ),對數(shù)控機床的研究起步較早,對機床機械結(jié)構(gòu)的分析比較透徹,雖然還有進一步發(fā)展的空間,但是現(xiàn)有的動靜態(tài)研究方法已經(jīng)滿足當前設(shè)備發(fā)展的需求, 由這些設(shè)備制造出的工件也能滿足現(xiàn)在的精度要求。利用有限單元法對機械結(jié)構(gòu)進行分析在國外發(fā)展的也比較成熟,而且國外學者更重視把有限元法應(yīng)用在機械結(jié)構(gòu)的輔助設(shè)計上,并且取得了大量的研究成果。U.Heisel 與 A.Feinauer 研究了在高速磨削過程中振動產(chǎn)生的原因,例如變化的切削載荷是如何影響振動的,并在機床的模型上仿真了多種振動對工件質(zhì)量的影響,最后利用切削試驗對仿真結(jié)果進行了修正[f}l。韓國的 Dai Hilty lee 和 Jung Do suh 等人通過有限元分析了高速銑床的滑塊結(jié)構(gòu), 并從中研發(fā)出一種新型的滑塊結(jié)構(gòu),這種夾層復(fù)合結(jié)構(gòu)質(zhì)量輕、阻尼系數(shù)高【lob。西班牙的學者 MZatarain 分別采用 Nastran 和 I-deas 兩種軟件建立了立柱移動式銑床的整機模型,不僅包括主軸箱、立柱、床身等關(guān)鍵部件,還考慮了它們之間接觸面
10
的影響,在此基礎(chǔ)上,MZatarain 對整機進行了模態(tài)分析,通過幾種方案對比,選擇了較合理的結(jié)構(gòu)。Kennedy 和 Pancu 研究了如何才能精確的計算機械結(jié)構(gòu)固有頻率和阻尼比,為口后科研的應(yīng)用鋪平了道路。德國的 Bishop 通過自己多年的研究,在論文中從更深層的角度闡述了模態(tài)分析的原理,為后來的學者研究機械結(jié)構(gòu)的動態(tài)特性奠定了基礎(chǔ)。
3.2 國內(nèi)研究現(xiàn)狀
近年來,我國的玻璃行業(yè)發(fā)展的速度也比較快,玻璃加工企業(yè)的數(shù)量不斷增加, 企業(yè)規(guī)模也變得越來越大,作為玻璃加工企業(yè)的關(guān)鍵設(shè)備,玻璃磨邊機的市場需求將會越來越廣泛。但是就目前來看,國內(nèi)玻璃磨邊機研發(fā)力量薄弱,技術(shù)還不成熟,玻璃加工設(shè)備落后,自動化程度低,生產(chǎn)的玻璃質(zhì)量與西方發(fā)達國家相比差距甚遠,難以滿足我國玻璃加工行業(yè)快速發(fā)展的要求。而智能化自動化程度相對較高玻璃磨邊機,國內(nèi)機械生產(chǎn)水平還遠遠不能達到,所以仍然以從德國、意大利、瑞士等西方發(fā)達國的進口為主,導致我國玻璃生產(chǎn)企業(yè)在設(shè)備上投入了大量資金,已經(jīng)沒有能力改進或研發(fā)新,長此惡性循環(huán)發(fā)展下去,使我國企業(yè)對國外的玻璃設(shè)備生產(chǎn)企業(yè)依賴程度越來越高,當設(shè)備出現(xiàn)故障的時候,我國的技術(shù)人員往往解決不了,又需要花高昂的費用請國外的技術(shù)人員予以解決,這嚴重制約了我國機床裝備行業(yè)的發(fā)展。因此很多致力于振興我國機械行業(yè)的高等院校和科研機構(gòu)開始了探索,并取得了一定的科研成果。吉林大學的王龍山教授等經(jīng)過多年的研究,建立了砂輪磨削隨時間變化的數(shù)學模型,并利用計算機仿真技術(shù)模擬了磨削的實際過程,為以后學者進行磨削優(yōu)化、自動控制等提供了必要的理論基礎(chǔ)。長春大學的王穎淑等將砂輪上的磨粒進行簡化,研究它的切削狀態(tài),由此建立了外圓縱向磨削系統(tǒng)的力學模型,這為仿真外圓縱向磨削過程、實現(xiàn)磨削過程的自動控制提供了必要條件。在機床設(shè)計分析方面,東南大學倪曉宇、易紅等利用有限單元法對大型數(shù)控機床床身進行力學性能分析和動態(tài)特性分析,并根據(jù)漸進結(jié)構(gòu)優(yōu)化算法(ESO)對機床床身結(jié)構(gòu)進行了拓撲優(yōu)化,使 ESO 方法在機械結(jié)構(gòu)的優(yōu)化方面得到了很好的應(yīng)用。內(nèi)蒙古工業(yè)大學的楊明亞利用三維建模軟件建立了數(shù)控磨床立柱結(jié)構(gòu)的有限元模型,利用有限元分析 ANSYS 對立柱部分進行了模態(tài)分析,得到了立柱前五階固有頻率和振型。浙江大學現(xiàn)代制造工程研究所的楊曉京運用 ANSYS 軟件對 XM538 數(shù)控銑床的基座結(jié)構(gòu)進行了優(yōu)化設(shè)計,比較了四種結(jié)構(gòu)形式的基座的動態(tài)特性,提出在 XM538 數(shù)控銑床中選用內(nèi)側(cè)加強筋基座結(jié)構(gòu),可以大大提高機床機械性能。東南大學的伍建國等在對 K15280B 數(shù)控加工中心床身動態(tài)測試的基礎(chǔ)上,建立數(shù)控加工中心的有限元模型,并對其床身結(jié)構(gòu)進行了靜態(tài)特性和動態(tài)特性的分析,找到了現(xiàn)有數(shù)控加工中心在設(shè)計中存在的缺陷和不足,并從多個角度對加工中心進行了改進,經(jīng)過對比分析得到了結(jié)構(gòu)設(shè)計最合理的方案。東北大學張耀滿在CK5132 立式數(shù)控車削加工中心的研制過程中,在機床原有的結(jié)構(gòu)基礎(chǔ)上進行動力學分析,根據(jù)分析結(jié)果對機床進行了改進設(shè)計,從而提高數(shù)控機床的動態(tài)性能,并與試驗結(jié)果進行了對比分析,驗證結(jié)果的合理性。西安工業(yè)大學朱育權(quán)通過 ANSYS 軟件建立CL 140 數(shù)控機床的實體模型,采用四面體單元對模型進行網(wǎng)格劃分,得到了數(shù)控機床的前三階固有頻率和振型,根據(jù)對比分析找到了避開各階激振頻率的方法,有效的 提高了數(shù)控機床的抗振性能。
綜上所述,盡管國內(nèi)外許多學者對玻璃磨邊機進行了相關(guān)研究,并成功指導了工程實踐,但仍然存在值得深入研究的問題。
(1)目前雖然已有部分專家學者對磨削理論進行了研究,但主要是針對金屬材質(zhì)的工件,對玻璃、橡膠等非金屬材質(zhì)的工件研究較少。
(2)對玻璃磨邊機械結(jié)構(gòu)的設(shè)計仍然采用經(jīng)驗法,將各零部件盲目組裝,沒有考慮設(shè)備的振動性能以及局部的強度和剛度,影響了機床的整體性能。
(3)對玻璃磨邊機等數(shù)控機床結(jié)構(gòu)的設(shè)計從力學角度或振動角度孤立的分析,沒有將它們有機結(jié)合共同指導數(shù)控機床的結(jié)構(gòu)優(yōu)化。
因此,本文在綜合分析國內(nèi)外的研究現(xiàn)狀的基礎(chǔ)上,結(jié)合具體的工程實際,針對目前玻璃磨邊機研究存在的問題,對玻璃磨邊機主機架結(jié)構(gòu)力學性能、模態(tài)特性和結(jié)構(gòu)優(yōu)化等方面進行了深入的研究。
二、論文(設(shè)計)研究的內(nèi)容1.重點解決的問題
為達到預(yù)期目的,論文(設(shè)計)研究中應(yīng)重點解決的問題有:
(1) 給出磨邊機的結(jié)構(gòu)設(shè)計方案
(2) 根據(jù)磨削力校核相關(guān)構(gòu)件強度
(3) 計算分析及標準件的選擇
(4) 給出裝配圖和實體模型圖
2. 擬開展研究的幾個主要方面(論文寫作大綱或設(shè)計思路)
針對論文(設(shè)計)研究的問題,擬開展研究的主要思路如圖所示:
3. 本論文(設(shè)計)預(yù)期取得的成果
通過對玻璃磨邊機主機架的力學分析,預(yù)期實現(xiàn)的成果如下;
(1) 利用數(shù)值分析軟件得出磨邊機工作時磨輪受力的曲線圖;
(2) 利用三維建模軟件建立玻璃磨邊機的實體模型;
(3) 依據(jù)分析結(jié)果對玻璃磨邊機力學性能進行校驗;
(4) 分析玻璃磨邊機的動態(tài)特性,確定玻璃磨邊機的臨界轉(zhuǎn)速;
(5) 研究力學性能析和模態(tài)特性分析的結(jié)果,建立玻璃磨邊機主機架結(jié)構(gòu)的參
數(shù)化模型,選擇合適的設(shè)計變量、目標函數(shù)和約束條件,對設(shè)計變量進行靈敏度分析,確定各個輸入輸出參數(shù)的優(yōu)先級;
(6) 歸納總結(jié)研究結(jié)論,提出相應(yīng)改進措施。
三、論文(設(shè)計)工作安排
1. 擬采用的主要研究方法(技術(shù)路線或設(shè)計參數(shù));
有限元分析是使用有限元方法來分析靜態(tài)或動態(tài)的物理物體或物理系統(tǒng)。在這種方法中一個物體或系統(tǒng)被分解為由多個相互聯(lián)結(jié)的、簡單、獨立的點組成的幾何模型。在這種方法中這些獨立的點的數(shù)量是有限的,因此被稱為有限元。
有限元分析法(FEA)已應(yīng)用得非常廣泛,現(xiàn)已成為年創(chuàng)收達數(shù)十億美元的相關(guān)產(chǎn)業(yè)的基礎(chǔ)。即使是很復(fù)雜的應(yīng)力問題的數(shù)值解,用有限元分析的常規(guī)方法就能得到。通過本科四年的學習,以及對機械領(lǐng)域的綜合技術(shù)的一定了解,擬采用有限元分析的方法對兆瓦級風電系統(tǒng)齒輪主軸進行動力學特性分析,完成畢業(yè)設(shè)計題目。
2. 論文(設(shè)計)進度計劃
論文起始周
計劃內(nèi)容
第 1 周
根據(jù)題目要求,編寫論文摘要
第 2 周
研究現(xiàn)有玻璃磨邊機結(jié)構(gòu),給出設(shè)計初步方案
第 3 周
結(jié)合設(shè)計參數(shù),對主要零部件進行設(shè)計,并畫出二維圖
第 4 周
電機選擇及強度校核
第 5 周
給出磨邊機裝配圖
第 6 周
完善結(jié)構(gòu),盡可能小型化便攜式
第 7 周
給出實體模型圖
第 8 周
完成畢業(yè)設(shè)計說明書初稿,并完成設(shè)計圖紙要求
第 9 周
翻譯外文文獻,并完善論文
第 10 周
完成畢業(yè)設(shè)計論文,完成答辯 PPT
四、需要閱讀的參考文獻
[1] 孫國文. 玻璃磨邊機主機架結(jié)構(gòu)力學特性分析與優(yōu)化設(shè)計[D].武漢理工大學,20 14.
[2] 趙息平. 立式玻璃磨邊機磨削力測試分析與研究[D].北方工業(yè)大學,2013.
[3] 鄭曉麗. 立式玻璃磨邊機關(guān)鍵部件有限元分析及優(yōu)化設(shè)計[D].北方工業(yè)大學,20 13.
[4] 徐宏海,趙息平.立式玻璃磨邊機砂輪組件力矩傳遞特性測試分析[J].機械設(shè)計與制造,2012(11):211-213.
[5] 孔德帥,羅學科,徐宏海.立式磨邊機磨頭機構(gòu)的動態(tài)性能分析[J].機電工程,201 1,28(07):802-805.
[6]趙毅忠,祝本明.新型玻璃磨邊機數(shù)控系統(tǒng)[J].兵工自動化,2010,29(08):85-86. [7]許海峰,唐偉強,聶世濤,周靖.一種玻璃磨邊機及其多功能夾具的設(shè)計[J].機械 設(shè)計與制造,2010(03):240-241.
[8] 蔡小林,周會成,陳吉紅.新型數(shù)控玻璃磨邊機的開發(fā)[J].機械設(shè)計與制造,2007
(12):103-105.
[9] 李敬兆.S7-200PLC 實現(xiàn)的智能玻璃磨邊機研究[J].安徽理工大學學報(自然科學版),2005(02):45-49.
[10] 張錫珍.新型玻璃磨邊機試制成功[J].建材工業(yè)信息,1992(20):11. [11]Jian Hu,Zhan Jin Wang,Bin Duan,Gang Yan Li. Optimization Design Meth od for Body Frame of Vehicular Glass Edge Grinding Machine Based on Goal
-Driven Optimization[J]. Applied Mechanics and Materials,2013,2549(345).
[12]Bing Deng,Guo Qiang Shen. The Application of Fuzzy PID Control Algor ithm in Variable Frequency Speed Regulation System of Glass Edge Grindin g Machine[J]. Applied Mechanics and Materials,2015,3675(697). [13]BELLI, MARCO, GERVASONI, MASSIMILIANO. Machine for grinding the edge s of plates of glass, marble, and stone materials in general, with integ rated drilling/milling unit[P]. :EP2687327,2014-01-22.
[14]Belli, Marco, Gervasoni, Massimiliano. Machine for grinding the edge
s of plates of glass, marble, and stone materials in general, with integ rated drilling/milling unit[P]. :EP2687327,2017-03-22.
[15]BELLI, MARCO, GERVASONI, MASSIMILIANO. Machine for grinding the edge s of plates of glass, marble, and stone materials in general, with integ rated drilling/milling unit[P]. :EP2687327,2014-01-22.
附:文獻綜述
文獻綜述
詳細閱讀參考文獻后,對各個文獻的研究成果及局限性進行了如下歸納。文獻 1
1. 研究成果:
(1) 玻璃磨邊機磨邊系統(tǒng)力學特性分析。調(diào)研了全自動玻璃預(yù)處理生產(chǎn)線, 在研究了玻璃磨邊機的結(jié)構(gòu)組成和工藝流程,在此基礎(chǔ)上從簡化的單個磨粒的切削狀態(tài)出發(fā),建立了玻璃磨邊機在工作過程時系統(tǒng)力學模型,利用數(shù)值分析軟件 Matlab 得出磨邊機工作時磨輪受力的曲線圖,為后文進行玻璃磨邊機的有限元分析提供力學支撐。
(2) 建立了玻璃磨邊機的有限元模型。利用三維建模軟件 Pro/E 建立了玻
璃磨邊機的實體模型,研究了建模軟件與有限元軟件之間的數(shù)據(jù)接口和格式轉(zhuǎn)換,將 Pro/E 與 ANSYS 無縫連接,而后把簡化后的玻璃磨邊機模型導 ANSYS Workbench 中,經(jīng)過單元選擇、材料定義、網(wǎng)格劃分完成玻璃磨邊機有限元模型的建立。
(3) 玻璃磨邊機實體模型的有限元分析。在磨削系統(tǒng)力學模型和磨輪受力
曲線的基礎(chǔ)上,對玻璃磨邊機主機架進行力學性能分析,得出磨邊機極限工況下的變形圖和應(yīng)力圖,根據(jù)分析結(jié)果對現(xiàn)有磨邊機結(jié)構(gòu)設(shè)計進行評價。在模態(tài)分析理論的基礎(chǔ)上,利用 ANSYS Workbench 軟件對玻璃磨邊機進行動態(tài)特性分析,根據(jù)提取的前六階頻率和振型,研究磨輪電機的臨界轉(zhuǎn)速。
(4) 玻璃磨邊機主機架結(jié)構(gòu)的優(yōu)化設(shè)計。在玻璃磨邊機力學性能分析和模
態(tài)特性分析的基礎(chǔ)上,建立了以變形量為目標函數(shù),低階頻率、質(zhì)量、最大應(yīng)力為約束,主機架截面寬度、厚度、高度為設(shè)計變量的優(yōu)化模型。根據(jù) GOE 法研究磨邊機各個輸入輸出參數(shù)的靈敏度,確定了它們的優(yōu)先級,利用 ANSYS Workbench 中的 Design Exploration 模塊完成主機架的優(yōu)化設(shè)計。
2. 局限性
(1) 建立的玻璃磨邊機磨削系統(tǒng)力學模型在進行計算時許多參數(shù)都是取的
經(jīng)驗值,可以考慮將力學模型與實驗相結(jié)合,通過兩者結(jié)果的對比對力學模型參數(shù)及時進行修正。
(2) 玻璃磨邊機主機架結(jié)構(gòu)進行模態(tài)分析時,外界的激振頻率只考慮了磨
輪電機的轉(zhuǎn)速,將磨輪電機轉(zhuǎn)速應(yīng)該遠離磨邊機固有頻率作為重要的約束條件實現(xiàn)了主機架的優(yōu)化。實際上磨邊機工作時外界的激振頻率還有很多,學者可以深入研究其他影響磨邊機動態(tài)特性的因素。
(3) 本文對玻璃磨邊機主機架結(jié)構(gòu)的有限元分析是在常溫下進行的,實際
上磨邊機工作時由于磨削、電機高速旋轉(zhuǎn)等因素會產(chǎn)生大量熱,這些熱量對機械結(jié)構(gòu)的影響也是不可忽略的,因此玻璃磨邊機主機架結(jié)構(gòu)的熱力藕合分析還有待進一步的研究。
文獻 2
1. 研究成果
(1) 通過在電機軸末端設(shè)置推力球軸承,負載力矩經(jīng)軸套傳遞到砂輪電機軸的磨削力矩傳遞率達到 98%,而且恒定不變,比不加推力球軸承時高出 20%。負載力矩與傳遞到電機軸上的力矩之間具有良好的線性關(guān)系,能夠滿足工程測試對傳感器信號線性度的要求。因此,可以通過在砂輪電機定位軸套上粘貼電阻應(yīng)變片的方式,制作應(yīng)變式力矩傳感器,測量玻璃磨邊加工過程中的磨削力矩。
(2) 以階梯軸套為彈性元件,在軸套的外表面粘貼兩組電阻應(yīng)變片,制作了通過多
點接觸導電滑環(huán)為測量電橋供電和傳遞測試信號的應(yīng)變式磨削測力儀。對磨削力儀進行標定、磨削力模擬測試和精度檢測,結(jié)果表明電機軸末端加推力球軸承后,切向磨削力 FT 和徑向磨削力 Fn 的傳遞率分別為 97%和 70%,比不加推力球軸承提高了 20% 測力儀測量誤差小于 5%該測力儀具有結(jié)構(gòu)精巧,成本低廉,安裝和拆卸方便,不需要改裝玻璃磨邊機、可在正常生產(chǎn)條件下測量磨削力等優(yōu)點。
2. 局限性
(1) 磨削力試驗過程中,僅考慮了砂輪線速度,玻璃進給速度,玻璃倒角。對磨削力的影響,沒有考慮到玻璃厚度,砂輪粒度和砂輪振動對磨削力的影響。
(2) 未對磨削力測試信號的動態(tài)特性作進一步分析研究文獻 3
1. 研究成果
(1) 根據(jù)機架、支撐架和夾送輥的實際受力情況,對機架、支撐架和夾送輥分別進行了有限元靜力分析,分析得出:機架的最大應(yīng)力值為 21.4Mpa,最大變形為 0.173 mm;支撐架的最大應(yīng)力值為 34.3Mpa, 最大變形為 0.186mm; 夾送輥的最大應(yīng)力值為68.3Mpa,最大變形為 0.670mm。由分析結(jié)果可知,機架、支撐架和夾送輥均能夠滿足強度和剛度要求,但是在材料利用上都存在很大的浪費。
(2) 以提高機架結(jié)構(gòu)的材料利用率為目的,對機架進行了改進設(shè)計與分析。改進方法是保持機架原有的結(jié)構(gòu)形式不變,將機架原本的空心方管尺寸 100X 100X5 mm 替換為 92X92X5 mm。進后機架結(jié)構(gòu)的有限元靜力分析結(jié)果表明,改進后機架的最大應(yīng)力值為 25.6Mpa,最大變形為 0.247mm,不僅仍然能夠滿足強度和剛度要求,而且比改進前的機架節(jié)省材料 12.43%,達到了節(jié)約材料的目的。
(3) 以提高支撐架結(jié)構(gòu)的材料利用率為目的,對支撐架進行了改進設(shè)計與分析。改進措施是保持支撐架的結(jié)構(gòu)形式不變,將支撐架原有的 100X100X5 的空心方管替換為92X92X5 mm 的空心方管、將 100X50X5 mm 心矩形管替換為 90X40X5 mm 的空心矩形管。改進后支撐架結(jié)構(gòu)的有限元靜力分析結(jié)果表明, 改進后支撐架的最大應(yīng)力值為56.4Mpa,最大變形為 0.262nnn,不僅仍然能夠滿足強度和剛度要求,而且比改進前的支撐架節(jié)省材料 18.24%,達到了節(jié)約材料的目的。
(4) 為了提高材料的利用率和降低立式玻璃磨邊機的制造成本,通過將夾送輥的聚氨酚橡膠層壁厚 9 mm 改為 5m,將鋼管的壁厚 15mm 改為 10mm 的方式對夾送的結(jié)構(gòu)改進設(shè)汁。在對改進后的夾送輥結(jié)構(gòu)有限元靜力分析后得知,改進后夾送輥的最大應(yīng)力值為 85.4Mpa 最大變形為 0.838mm,不僅仍然能夠滿足強度和剛度要求,而且比改進前的夾送輥節(jié)省材料 29.35%,達到了節(jié)約材料的目的。
2. 局限性
(1) 僅對支撐架、機架和夾送輥進行了有限元靜力分析,若要更準確驗證其是否具有足夠的強度和剛度,應(yīng)對支撐架、機架和夾送輥做一些有限元動態(tài)分析。
(2) 在對支撐架、機架和夾送輥的有限元靜力分析完成后,憑借經(jīng)驗對其結(jié)構(gòu)進行
了改進。在以后的工作中,可以利用 ANSYS 優(yōu)化工具,通過設(shè)定具體的優(yōu)化參數(shù)對支撐架、機架和夾送輥進行優(yōu)化設(shè)計。
(3) 僅從仿真角度和理論角度對支撐架、機架和夾送輥的結(jié)構(gòu)進行有限元靜力分析、對下磨頭傳動系統(tǒng)和玻璃傳送系統(tǒng)進行優(yōu)化設(shè)計,缺少通過試驗來驗證分析結(jié)果的正確性這一環(huán)節(jié)。在后續(xù)研究中,可以適當增加試驗環(huán)節(jié)。
文獻 5
1. 研究成果
(1) 通過合理的模型簡化和單元類型的選擇,本研究 建立了三維有限元實體模型, 利用彈簧阻尼單元 COMBIN14 模擬了結(jié)合部的特性,得出在考慮上磨頭 機構(gòu)的絲杠
螺母軸承和導軌結(jié)合面情況下的上磨頭機 構(gòu)整體的動態(tài)特性,得到前 1 階 ~ 5 階固有頻率分別 在 33、 44、 97、 105、 119 Hz 附近,并與剛性連接的情況 作對比分析得出,結(jié)合面對高階固有頻率的影響較為 顯著,振型上主要表現(xiàn)在局部結(jié)構(gòu)的振型。
(2) 本研究還通過諧響應(yīng)分析模擬了上磨頭實際工作 時的狀態(tài),得出頻率在 30 ~
45 Hz 之間砂輪中心 Z 方 向的諧響應(yīng)振幅最大,這是造成磨邊不均勻現(xiàn)象的原 因之一。
文獻 6
研究成果
新型玻璃磨邊機數(shù)控系統(tǒng)技術(shù)已應(yīng)用與多數(shù)口徑炮彈紫東合膛設(shè)備中,具有成本低,對工作環(huán)境要求不高,易于控制的特點。該技術(shù)已投入實際批量生產(chǎn),不僅大大減輕了工人的勞動強度,還提高了大口徑炮彈的裝配檢測的技術(shù)水平和安全性,解決了生產(chǎn)過程中存在的安全,質(zhì)量和效率等問題,具有較好的推廣利用價值。
文獻 7
研究成果
講逆向工程與數(shù)值模擬技術(shù)相結(jié)合,作為一種新模具修復(fù)手段。以原始樣件進行逆向測量,將重構(gòu)所得CAD 模型作為原始凹模型面,運用有限元方法進行沖壓成型模擬和分析,進而成功復(fù)制出原始產(chǎn)品。避免了模具無法修復(fù)而報廢的情況。
文獻 8
研究成果
新型數(shù)控玻璃磨邊機集成了 CAD/CAM, 目前主要可以磨削 以下幾種玻璃形狀: 若干段直線段構(gòu)成的凸多邊形, 若干段圓弧 構(gòu)成的非凹封閉曲線, 若干段直線與圓弧構(gòu)成的非凹封閉形, 橢 圓以及其它具有確定函數(shù)關(guān)系的非凹曲線。該類型的磨邊機適 合磨削數(shù)碼相機、手機的玻璃顯示屏等尺寸不大的玻璃。
文獻 9
研究成果
方圓玻璃機械廠生產(chǎn)的玻璃磨邊機實現(xiàn)了智 能控制 ,使玻璃的磨削精度和磨削速度均得到顯著 提高 ,玻璃花邊的磨削質(zhì)量和產(chǎn)品檔次均得到明顯 改善 ,進料速度: 0. 5 m /min~ 5 m /min 無級可調(diào) , 以直角花邊為例: 直邊最大磨削量達 3 mm、磨削 誤差小于 0. 05 mm、棱角最大磨削寬度可達 2. 5 mm、棱角角度為 45° 、玻璃板厚度為 3~ 12 mm,產(chǎn) 品深受用戶歡迎。由于產(chǎn)品開發(fā)時間和 PLC 功能 的限制 , 未將基于神經(jīng)網(wǎng)絡(luò)變結(jié)構(gòu)控制應(yīng)用到該系 統(tǒng)中 ,作者正在 LPC2214 上開發(fā) ,以期盡快應(yīng)用到 實際中去 ,進一步提高系統(tǒng)控制精度和產(chǎn)品質(zhì)量。
文獻 10
研究成果
把萬向球式工作臺面改成氣墊桌式,。臺面上貼上橡膠條,膠條間隔貼成肋狀氣孔打在膠條上,肋間的槽可順利的排水,排渣,經(jīng)使用效果良好。
臺面可按大玻璃規(guī)模制造,中間站人的位置可適當凹進,這樣就兼顧多種規(guī)格。磨小規(guī)格玻璃時因漏氣面積大,玻璃浮不起來,可在氣箱中加蝶形閥,使氣流集中于使用區(qū),風機要適當大一些。
這種玻璃磨邊機克服了原萬向球式工作臺手磨磨邊機的許多缺點。萬向球式工作
臺臺面不但不易調(diào)平,而且又容易松動,球架易生銹,轉(zhuǎn)動不靈活,球的材質(zhì)難選, 易給玻璃造成擦傷,是玻璃表面失光。