貨車轉(zhuǎn)向橋設(shè)計(jì)【輕型貨車】
貨車轉(zhuǎn)向橋設(shè)計(jì)【輕型貨車】,輕型貨車,貨車轉(zhuǎn)向橋設(shè)計(jì)【輕型貨車】,貨車,轉(zhuǎn)向,設(shè)計(jì),輕型
本科畢業(yè)設(shè)計(jì)（論文）開 題 報(bào) 告
題 目 輕型貨車轉(zhuǎn)向橋設(shè)計(jì)
指 導(dǎo) 教 師
院（系、部） 機(jī)械工程學(xué)院
專 業(yè) 班 級(jí)
學(xué) 號(hào)
姓 名
日 期
教務(wù)處印制
一、選題的目的、意義和研究現(xiàn)狀
我國(guó)作為一個(gè)發(fā)展中國(guó)家,汽車使用越來越多，而當(dāng)前由于設(shè)計(jì)方案所限,不能精確地選擇零部件的尺寸和結(jié)構(gòu),造成有的地方強(qiáng)度不夠,而有的地方強(qiáng)度又過剩,嚴(yán)重地影響了產(chǎn)品的開發(fā)和設(shè)計(jì),造成直接經(jīng)濟(jì)損失.特別對(duì)于諸如轉(zhuǎn)向橋等部件,因不能準(zhǔn)確確定其失效原因和部位,造成不能從根本上解決其失效問題。不同類型的貨車在我國(guó)的市場(chǎng)中占有相當(dāng)大的比例，他們的性能的好、壞在一定程度上也影響著汽車在市場(chǎng)上的地位。
針對(duì)以上問題，本設(shè)計(jì)選用貨車的轉(zhuǎn)向橋作為設(shè)計(jì)對(duì)象，通過合理的計(jì)算，結(jié)構(gòu)設(shè)計(jì)，而達(dá)到汽車轉(zhuǎn)向橋具有較好的轉(zhuǎn)向靈敏性。希望取得一個(gè)較好的結(jié)果，使貨車轉(zhuǎn)向橋提到一個(gè)新水平。
轉(zhuǎn)向橋是汽車的重要組成部分，轉(zhuǎn)向橋是利用車橋中的轉(zhuǎn)向節(jié)使車輪可以偏移一定角度，并承受地面與車架之間的力及力矩,以實(shí)現(xiàn)汽車的轉(zhuǎn)向。因此，汽車轉(zhuǎn)向橋的設(shè)計(jì)也是很重要的。
轉(zhuǎn)向橋體作為汽車的主要部件，受多種載荷作用，特別容易產(chǎn)生形變，造成零部件失效，影響整機(jī)的使用壽命，為此必須對(duì)轉(zhuǎn)向橋體進(jìn)行優(yōu)化設(shè)計(jì)與分析。
通過大學(xué)四年學(xué)習(xí)的知識(shí)，對(duì)汽車轉(zhuǎn)向橋做出合理的設(shè)計(jì)。對(duì)所學(xué)的專業(yè)基礎(chǔ)知識(shí)和研究能力、自學(xué)能力以及各種綜合能力的檢驗(yàn)。通過做畢業(yè)論文的形式，可以使我在綜合能力、治學(xué)方法等方面得到鍛煉，使之進(jìn)一步理解所學(xué)專業(yè)知識(shí)，擴(kuò)大知識(shí)面。
二、研究方案及預(yù)期結(jié)果
（設(shè)計(jì)方案或論文主要研究?jī)?nèi)容、主要解決的問題、理論、方法、技術(shù)路線及論文框架等）
本設(shè)計(jì)介紹了轉(zhuǎn)向橋的概念和原理,總理布局,主要通過對(duì)機(jī)械設(shè)計(jì)的學(xué)習(xí)、了解和掌握,來設(shè)計(jì)轉(zhuǎn)向橋的各個(gè)組成零件,使其具有精確的尺寸和結(jié)構(gòu),最后通過合理的結(jié)構(gòu)安排,組裝成貨車轉(zhuǎn)向橋。
本設(shè)計(jì)主要解決的問題是使輕型貨車轉(zhuǎn)向橋的具有較好的穩(wěn)定性和轉(zhuǎn)向靈敏性。
本設(shè)計(jì)《汽車設(shè)計(jì)》為理論基礎(chǔ)，在設(shè)計(jì)中確定了轉(zhuǎn)向橋設(shè)計(jì)方案，設(shè)計(jì)了轉(zhuǎn)向橋及其零件組成，通過計(jì)算設(shè)計(jì)出了主要零件的尺寸、強(qiáng)度和合理的整體布局。
為了能更好的說明問題，在論文的第一章首先介紹了轉(zhuǎn)向橋的定義及用途，然后在第二章介紹了轉(zhuǎn)向橋的結(jié)構(gòu)，第三章主要針對(duì)轉(zhuǎn)向橋的計(jì)算，第四章介紹了轉(zhuǎn)向橋的實(shí)驗(yàn)。最后畫出轉(zhuǎn)向橋的裝配圖和一些關(guān)鍵零件圖。
設(shè)計(jì)后的轉(zhuǎn)向橋具有結(jié)構(gòu)緊湊、重量輕、轉(zhuǎn)向靈敏的特點(diǎn)，制造容易。廣泛用于微、輕型載貨汽車。其結(jié)構(gòu)簡(jiǎn)單,價(jià)格低廉,充分體現(xiàn)的貨車轉(zhuǎn)向橋的特點(diǎn)。其貨車轉(zhuǎn)向橋的計(jì)算和結(jié)構(gòu)布局,也為其他貨車轉(zhuǎn)向橋提供了設(shè)計(jì)方法和思路。
三、研究進(jìn)度
1. 調(diào)研，查找相關(guān)資料,提交開題報(bào)告（第5周）
2. 確定總體設(shè)計(jì)方案以及知識(shí)準(zhǔn)備（第6—7周）
3. 完成參數(shù)計(jì)算及主要設(shè)計(jì)工作（第8—13周）
4. 整理論文（第14—16周）
5. 準(zhǔn)備答辯（第17周）
四、主要參考文獻(xiàn)
[1] 王洪欣.機(jī)械設(shè)計(jì)工程學(xué)（Ⅰ）[M].徐州:中國(guó)礦業(yè)大學(xué)出版社,2001.
[2] 王洪欣.機(jī)械設(shè)計(jì)工程學(xué)（Ⅱ）[M].徐州:中國(guó)礦業(yè)大學(xué)出版社,2001.
[3] 竺延年.最新車橋設(shè)計(jì)、制造、質(zhì)量檢測(cè)及國(guó)內(nèi)外實(shí)用手冊(cè)[M].中國(guó)知識(shí)出版社,2005.
[4] 陳家瑞.汽車結(jié)構(gòu)[M].吉林工業(yè)大學(xué),2000.
[5] 徐清富.國(guó)外汽車最近結(jié)構(gòu)手冊(cè)[M].北京:機(jī)械工業(yè)出版社,1996.
[6] D.J.Segal.Highway Vehic Object Simulation Model[M].Programmers Manual,1976.
[7] 程振彪.世界載貨汽車工業(yè)最新發(fā)展動(dòng)態(tài)[M].汽車科技,2001.
[8] 謝衛(wèi)國(guó),汪紅心.貨車平順性預(yù)測(cè)與優(yōu)化.汽車工程[J],1991（3）.
[9] 神龍汽車有限公司著編.中國(guó)轎車叢書-富康[M].北京:北京理工大學(xué)出版社,1998.
[10] 中國(guó)第一汽車集團(tuán)公司著編.中國(guó)轎車叢書-紅旗[M].北京:北京理工大學(xué)出社,1998.
[11] 李卓森等編.中外汽車圖冊(cè)車身分冊(cè)(一) [M].長(zhǎng)春:吉林科學(xué)技術(shù)出版社,1995.
五、指導(dǎo)教師意見
指導(dǎo)教師簽字：
摘要
我國(guó)汽車的轉(zhuǎn)向橋一直是該行業(yè)見研究人員不停探索和研究的重要方向之一。本設(shè)計(jì)主要針對(duì)輕型貨車轉(zhuǎn)向橋的進(jìn)行設(shè)計(jì)，通過合理的計(jì)算，結(jié)構(gòu)設(shè)計(jì)，而使汽車轉(zhuǎn)向橋具有較好的轉(zhuǎn)向靈敏性。
本設(shè)計(jì)介紹了轉(zhuǎn)向橋的概念和原理，總體布局，主要通過對(duì)機(jī)械設(shè)計(jì)的學(xué)習(xí)、了解和掌握，來設(shè)計(jì)轉(zhuǎn)向橋的各個(gè)組成零件，使其具有精確的尺寸和結(jié)構(gòu)，最后通過合理的結(jié)構(gòu)安排，組裝成貨車轉(zhuǎn)向橋。
設(shè)計(jì)后的轉(zhuǎn)向橋具有結(jié)構(gòu)緊湊、重量輕、轉(zhuǎn)向靈敏的特點(diǎn)，制造容易。廣泛用于微、輕型載貨汽車。其結(jié)構(gòu)簡(jiǎn)單，價(jià)格低廉，充分體現(xiàn)的輕型貨車轉(zhuǎn)向橋的特點(diǎn)。其轉(zhuǎn)向橋的計(jì)算和結(jié)構(gòu)布局，也為其他貨車轉(zhuǎn)向橋提供了設(shè)計(jì)方法和思路。
關(guān)鍵詞：轉(zhuǎn)向橋；計(jì)算；結(jié)構(gòu)
Abstract
In our country design of automobile's steering axle has always been one of the most important areas in which a lot of researches have been made. Our design mainly focus on the design of van's steering axle, with reasonable computation and structure design, we achieved good agility of automobile's steering axle.
This design introduced steering axle's concept and principles, general planning, from the study and grasp of mechanism design, we design steering axle's components with accolade size and structure, through reasonable structure deployment, we can compose the van's steering axle.
The steering axle we designed has many characteristics such as good compaction in structure, light weight, good agility and also it is easy to produce. it can be widely used in minimize、light truck. Its simple structure and low price fully embodies the features of van's steering axle. Van steering axle's computation and structure deployment also provide a good design method for other van's steering axle.
Key words: steering axle ;account ; structure
II
中文題目：輕型貨車轉(zhuǎn)向橋
外文題目：STEERING AXLE OF LIGHT TRUCK
目錄
前言 ………………………………………………………………………………1
1 轉(zhuǎn)向橋 …………………………………………………………………………2
1.1轉(zhuǎn)向橋的定義…………………………………………………………………2
1.2轉(zhuǎn)向橋的安裝形式……………………………………………………………2
2 轉(zhuǎn)向橋的結(jié)構(gòu) …………………………………………………………………3
2.1組成轉(zhuǎn)向橋的組成部分………………………………………………………3
2.2組成轉(zhuǎn)向橋的結(jié)構(gòu)及其影響因素……………………………………………5
3 轉(zhuǎn)向橋的設(shè)計(jì)計(jì)算 ……………………………………………………………8
3.1 轉(zhuǎn)向橋主要零件尺寸的確定 ………………………………………………8
3.2 非斷開式轉(zhuǎn)向從動(dòng)橋前梁應(yīng)力計(jì)算………………………………………10
3.2.1 在制動(dòng)情況下的前梁應(yīng)力計(jì)算…………………………………………10
3.2.2 在最大側(cè)向力（側(cè)滑）工況下的前梁應(yīng)力計(jì)算………………………11
3.3 轉(zhuǎn)向節(jié)在制動(dòng)和側(cè)滑工況下的應(yīng)力計(jì)算…………………………………12
3.3.1 工況下的轉(zhuǎn)向節(jié)應(yīng)力計(jì)算………………………………………………13
3.3.2 在汽車側(cè)滑工況下的轉(zhuǎn)向節(jié)應(yīng)力計(jì)算…………………………………14
3.4 主銷與轉(zhuǎn)向節(jié)襯套在制動(dòng)和側(cè)滑工況下的應(yīng)力計(jì)算……………………14
3.4.1 在汽車制動(dòng)工況下的計(jì)算………………………………………………14
3.4.2 在汽車側(cè)滑工況下的計(jì)算………………………………………………15
3.5 推力軸承和止推墊片的計(jì)算………………………………………………17
3.5.1 推力軸承計(jì)算 ………………………………………………………… 17
3.5.2 轉(zhuǎn)向節(jié)止推墊片的計(jì)算…………………………………………………18
4 轉(zhuǎn)向橋定位參數(shù) ……………………………………………………………19
4.1 主銷后傾角…………………………………………………………………19
4.2 主銷內(nèi)傾角…………………………………………………………………20
4.3 車輪外傾角…………………………………………………………………21
4.4 車輪前束……………………………………………………………………21
5 轉(zhuǎn)向橋?qū)嶒?yàn) …………………………………………………………………23
5.1 車道路實(shí)驗(yàn)、使用實(shí)驗(yàn)及整車室內(nèi)臺(tái)架試驗(yàn)……………………………23
5.2 轉(zhuǎn)向橋在扭力機(jī)上進(jìn)行靜扭轉(zhuǎn)強(qiáng)度實(shí)驗(yàn)…………………………………24
6 結(jié)論……………………………………………………………………………25
致謝………………………………………………………………………………26
參考文獻(xiàn)…………………………………………………………………………27
附錄 A譯文 ……………………………………………………………………28
附錄 B外文文獻(xiàn) ………………………………………………………………34
附錄A
數(shù)控技術(shù)發(fā)展
數(shù)控技術(shù)和數(shù)控裝備是制造工業(yè)現(xiàn)代化的重要基礎(chǔ)。這個(gè)基礎(chǔ)是否牢固直接影響到一個(gè)國(guó)家的經(jīng)濟(jì)發(fā)展和綜合國(guó)力，關(guān)系到一個(gè)國(guó)家的戰(zhàn)略地位。因此，世界上各工業(yè)發(fā)達(dá)國(guó)家均采取重大措施來發(fā)展自己的數(shù)控技術(shù)及其產(chǎn)業(yè)。
在我國(guó)，數(shù)控技術(shù)與裝備的發(fā)展亦得到了高度重視，近年來取得了相當(dāng)大的進(jìn)步。特別是在通用微機(jī)數(shù)控領(lǐng)域，以PC平臺(tái)為基礎(chǔ)的國(guó)產(chǎn)數(shù)控系統(tǒng)，已經(jīng)走在了世界前列。但是，我國(guó)在數(shù)控技術(shù)研究和產(chǎn)業(yè)發(fā)展方面亦存在不少問題，特別是在技術(shù)創(chuàng)新能力、商品化進(jìn)程、市場(chǎng)占有率等方面情況尤為突出。在新世紀(jì)到來時(shí)，如何有效解決這些問題，使我國(guó)數(shù)控領(lǐng)域沿著可持續(xù)發(fā)展的道路，從整體上全面邁入世界先進(jìn)行列，使我們?cè)趪?guó)際競(jìng)爭(zhēng)中有舉足輕重的地位，將是數(shù)控研究開發(fā)部門和生產(chǎn)廠家所面臨的重要任務(wù)。為完成此任務(wù)，首先必須確立符合中國(guó)國(guó)情的發(fā)展道路。為此，本文從總體戰(zhàn)略和技術(shù)路線兩個(gè)層次及數(shù)控系統(tǒng)、功能部件、數(shù)控整機(jī)等幾個(gè)具體方面探討了新世紀(jì)的發(fā)展途徑。
1 總體戰(zhàn)略
制定符合中國(guó)國(guó)情的總體發(fā)展戰(zhàn)略，對(duì)21世紀(jì)我國(guó)數(shù)控技術(shù)與產(chǎn)業(yè)的發(fā)展至關(guān)重要。通過對(duì)數(shù)控技術(shù)和產(chǎn)業(yè)發(fā)展趨勢(shì)的分析和對(duì)我國(guó)數(shù)控領(lǐng)域存在問題的研究，我們認(rèn)為以科技創(chuàng)新為先導(dǎo)，以商品化為主干，以管理和營(yíng)銷為重點(diǎn)，以技術(shù)支持和服務(wù)為后盾，堅(jiān)持可持續(xù)發(fā)展道路將是一種符合我國(guó)國(guó)情的發(fā)展數(shù)控技術(shù)和產(chǎn)業(yè)的總體戰(zhàn)略。
1.1 以科技創(chuàng)新為先導(dǎo)
中國(guó)數(shù)控技術(shù)和產(chǎn)業(yè)經(jīng)過40多年的發(fā)展，從無到有，從引進(jìn)消化到擁有自己獨(dú)立的自主版權(quán)，取得了相當(dāng)大的進(jìn)步。但回顧這幾十年的發(fā)展，可以看到我們?cè)跀?shù)控領(lǐng)域的進(jìn)步主要還是按國(guó)外一些模式，按部就班地發(fā)展，真正創(chuàng)新的成分不多。這種局面在發(fā)展初期的起步階段，是無可非議的。但到了世界數(shù)控強(qiáng)手如林的今天和知識(shí)經(jīng)濟(jì)即將登上舞臺(tái)的新世紀(jì)，這一常規(guī)途徑就很難行通了。例如，在國(guó)外模擬伺服快過時(shí)時(shí)，我們開始搞模擬伺服，還沒等我們占穩(wěn)市場(chǎng)，技術(shù)上就已經(jīng)落后了；在國(guó)外將脈沖驅(qū)動(dòng)的數(shù)字式伺服打入我國(guó)市場(chǎng)時(shí)，我們就跟著搞這類所謂的數(shù)字伺服，但至今沒形成大的市場(chǎng)規(guī)模；近來國(guó)外將數(shù)字式伺服發(fā)展到用網(wǎng)絡(luò)（通過光纜等）與數(shù)控裝置連接時(shí)，我們又跟著發(fā)展此類系統(tǒng)，前途仍不樂觀。這種老是跟在別人后面走，按國(guó)外已有控制和驅(qū)動(dòng)模式來開發(fā)國(guó)產(chǎn)數(shù)控系統(tǒng)，在技術(shù)上難免要滯后，再加上國(guó)外公司在我國(guó)境內(nèi)設(shè)立研究所和生產(chǎn)廠，實(shí)行就地開發(fā)、就地生產(chǎn)和就地銷售，使我們的產(chǎn)品在性能價(jià)格比上已越來越無多大優(yōu)勢(shì)，因此要進(jìn)一步擴(kuò)大市場(chǎng)占有率，難度自然就很大了。
為改變這種現(xiàn)狀，我們必須深刻理解和認(rèn)真落實(shí)“科學(xué)技術(shù)是第一生產(chǎn)力”的偉大論斷，大力加強(qiáng)數(shù)控領(lǐng)域的科技創(chuàng)新，努力研究具有中國(guó)特色的實(shí)用的先進(jìn)數(shù)控技術(shù)，逐步建立自己獨(dú)立的、先進(jìn)的技術(shù)體系。在此基礎(chǔ)上大力發(fā)展符合中國(guó)國(guó)情的數(shù)控產(chǎn)品，從而形成從數(shù)控系統(tǒng)、數(shù)控功能部件到種類齊全的數(shù)控機(jī)床整機(jī)的完整的產(chǎn)業(yè)體系。這樣，才不會(huì)被國(guó)外牽著鼻子，永遠(yuǎn)受別人的制約，才有可能用先進(jìn)、實(shí)用的數(shù)控產(chǎn)品去收復(fù)國(guó)內(nèi)市場(chǎng)，打開國(guó)際市場(chǎng)，使中國(guó)的數(shù)控技術(shù)和數(shù)控產(chǎn)業(yè)在21世紀(jì)走在世界的前列。
1.2 在商品化上狠下工夫
近幾年我國(guó)數(shù)控產(chǎn)品雖然發(fā)展很快，但真正在市場(chǎng)上站住腳的卻不多。就數(shù)控系統(tǒng)而言，國(guó)產(chǎn)貨仍未真正被廣大機(jī)床廠所接受，因此出現(xiàn)國(guó)產(chǎn)數(shù)控系統(tǒng)用于舊機(jī)床改造的例子較多，而裝備新機(jī)床的卻很少，機(jī)床廠出產(chǎn)的國(guó)產(chǎn)數(shù)控機(jī)床大多數(shù)用的都是國(guó)外的系統(tǒng)。這當(dāng)然不是說舊機(jī)床的數(shù)控化改造不重要，而是說明從商品的角度看，我們的數(shù)控系統(tǒng)與國(guó)外相比還存在相當(dāng)大的差距。
影響數(shù)控系統(tǒng)和數(shù)控機(jī)床商品化的主要因素除技術(shù)性能和功能外，更重要的就是可靠性、穩(wěn)定性和實(shí)用性。以往，一些數(shù)控技術(shù)和產(chǎn)品的研究、開發(fā)部門，所追求的往往是一些體現(xiàn)技術(shù)水平的指標(biāo)（如多少通道、多少軸聯(lián)動(dòng)、每分鐘多少米的進(jìn)給速度等等），而對(duì)影響實(shí)用性的一些指標(biāo)和一些小問題卻不太重視，在產(chǎn)品的穩(wěn)定性、魯棒性、可靠性、實(shí)用性方面花的精力相對(duì)較少。從而出現(xiàn)某些產(chǎn)品鑒定時(shí)的水平都很高，甚至也獲各種大獎(jiǎng)。但這些高指標(biāo)、高性能的產(chǎn)品到用戶哪兒卻由于一些小問題而表現(xiàn)不盡人意，最后喪失了信譽(yù)，打不開市場(chǎng)。這說明，高指標(biāo)、高性能的樣機(jī)型的產(chǎn)品離用戶真正需要的實(shí)用、可靠的商品是有相當(dāng)大的距離的，將一個(gè)高指標(biāo)、高性能的產(chǎn)品變?yōu)橐粋€(gè)有市場(chǎng)的商品還需作出大量艱苦的努力。
1.4 強(qiáng)技術(shù)支持和服務(wù)
數(shù)控系統(tǒng)和數(shù)控機(jī)床作為典型的高技術(shù)產(chǎn)品，對(duì)用戶的技術(shù)支持和服務(wù)是相當(dāng)重要的。以前國(guó)產(chǎn)數(shù)控產(chǎn)品喪失信譽(yù)的原因，除可靠性問題外，另一大問題就是缺乏有力的技術(shù)支持和服務(wù)。用戶花了很多錢買的數(shù)控機(jī)床或數(shù)控系統(tǒng)，一旦出現(xiàn)問題卻叫天天不應(yīng)，叫地地不靈，以后誰還敢買我們的產(chǎn)品。因此，應(yīng)將對(duì)用戶的技術(shù)支持和服務(wù)當(dāng)成重要的日常工作來抓，使我們?cè)谑袌?chǎng)上向縱深挺進(jìn)時(shí)，有一個(gè)強(qiáng)大后方。因此，為了取得數(shù)控產(chǎn)品市場(chǎng)競(jìng)爭(zhēng)的全面勝利，必須建立以技術(shù)支持和服務(wù)為核心的強(qiáng)大后方。當(dāng)然，為贏得主動(dòng)，后方也須主動(dòng)出擊。目前，利用先進(jìn)的信息技術(shù)手段（如網(wǎng)絡(luò)和多媒體），將為建立新一代立體化的技術(shù)支持和服務(wù)體系開辟新的途徑。
1.5 持續(xù)發(fā)展道路
可持續(xù)發(fā)展是下一世紀(jì)企業(yè)發(fā)展的重要戰(zhàn)略，我國(guó)數(shù)控產(chǎn)業(yè)要有大的發(fā)展也必須堅(jiān)持走可持續(xù)發(fā)展的道路。綠色是實(shí)現(xiàn)可持續(xù)發(fā)展的重要途徑，其主要思想是清潔和節(jié)約。為此應(yīng)大力加強(qiáng)綠色數(shù)控產(chǎn)品的開發(fā)，加速促進(jìn)數(shù)控產(chǎn)品、數(shù)控產(chǎn)業(yè)以及整個(gè)制造業(yè)的綠色化，主要戰(zhàn)略措施應(yīng)考慮以下幾方面：①有效減少產(chǎn)品制造及使用過程中的環(huán)境污染。如減少數(shù)控機(jī)床的鑄件結(jié)構(gòu)，消除鑄造對(duì)環(huán)境的污染；將數(shù)控機(jī)床主軸的潤(rùn)滑以油氣潤(rùn)滑、噴油潤(rùn)滑等取代油霧潤(rùn)滑，減少對(duì)生產(chǎn)環(huán)境的污染；在精密數(shù)控機(jī)床及其運(yùn)行環(huán)境的溫度控制中取消氟利昂制冷的恒溫技術(shù)；以電傳動(dòng)代替機(jī)械傳動(dòng)，減少噪聲污染。②大幅度降低資源消耗和能源消耗。如以軟件代替硬件，從而減少硬件制造的資源和能源消耗及污染，并減少產(chǎn)品壽命結(jié)束后硬件裝置的拆卸回收問題；以永磁驅(qū)動(dòng)代替感應(yīng)驅(qū)動(dòng)，提高效率和功率因數(shù)，節(jié)約能源；以電傳動(dòng)代替機(jī)械傳動(dòng)，提高效率，減少能源消耗。③加強(qiáng)用數(shù)控技術(shù)改造傳統(tǒng)機(jī)床。這既符合運(yùn)用信息技術(shù)和自動(dòng)化技術(shù)改造傳統(tǒng)產(chǎn)業(yè)，使傳統(tǒng)產(chǎn)業(yè)生產(chǎn)技術(shù)和裝備現(xiàn)代化這一產(chǎn)業(yè)可持續(xù)發(fā)展的目標(biāo)得以實(shí)現(xiàn)，又可取得巨大的經(jīng)濟(jì)效益。我國(guó)擁有普通機(jī)床數(shù)百萬臺(tái)，加強(qiáng)用數(shù)控技術(shù)改造傳統(tǒng)機(jī)床將成為下世紀(jì)我國(guó)數(shù)控領(lǐng)域的重要發(fā)展方向。④大力發(fā)展綠色數(shù)控機(jī)床。綠色數(shù)控機(jī)床應(yīng)是材料消耗少、能耗低、無污染，壽命長(zhǎng)且便于拆卸回收的新型機(jī)床。
2 技術(shù)途徑
2.1 發(fā)展具有中國(guó)特色的新一代PC數(shù)控系統(tǒng)
數(shù)控系統(tǒng)是各類數(shù)控裝備的核心，因此通過科技創(chuàng)新首先發(fā)展具有中國(guó)特色的新型數(shù)控系統(tǒng)，將是推動(dòng)數(shù)控產(chǎn)業(yè)化進(jìn)程的有效技術(shù)途徑。實(shí)踐證明，10年來我們所走的PC數(shù)控道路是完全正確的。PC機(jī)（包括工業(yè)PC）產(chǎn)量大、價(jià)格便宜，技術(shù)進(jìn)步和性能提高很快，且可靠性高（工業(yè)PC主機(jī)的MTBF已達(dá)30年［3］）。因此，以其作為數(shù)控系統(tǒng)的軟硬件平臺(tái)不但可以大幅度提高數(shù)控系統(tǒng)的性能價(jià)格比，而且還可充分利用通用微機(jī)已有軟硬件資源和分享計(jì)算機(jī)領(lǐng)域的最新成果，如大容量存儲(chǔ)器、高分辨率彩色顯示器、多媒體信息交換、聯(lián)網(wǎng)通訊等。此外，以通用微機(jī)作為數(shù)控平臺(tái)還可獲得快速的技術(shù)進(jìn)步，當(dāng)PC機(jī)升級(jí)換代時(shí)，數(shù)控系統(tǒng)也可相應(yīng)升級(jí)換代，從而長(zhǎng)期保持技術(shù)上的優(yōu)勢(shì)，在競(jìng)爭(zhēng)中立于不敗之地。
目前，PC數(shù)控系統(tǒng)的體系結(jié)構(gòu)有2種主要形式：（1）專用數(shù)控加PC前端的復(fù)合式結(jié)構(gòu)；（2）通用PC加位控卡的遞階式結(jié)構(gòu)。另外還有一種正在發(fā)展的數(shù)字化分布式結(jié)構(gòu)。其方案是將由DSP等組成的數(shù)字式伺服通過以光纜等為介質(zhì)的網(wǎng)絡(luò)與數(shù)控裝置連接起來，組成一完整的數(shù)控系統(tǒng)。這種系統(tǒng)雖然性能很好，但由于開發(fā)和生產(chǎn)成本太高，近期難以被國(guó)內(nèi)廣大用戶所接受。我們認(rèn)為，上述結(jié)構(gòu)并不是符合中國(guó)國(guó)情的最好方案，適合中國(guó)國(guó)情的應(yīng)是將所有數(shù)控功能全軟件化的集成式結(jié)構(gòu)，因?yàn)檫@種結(jié)構(gòu)的硬件規(guī)模最小，不但有利于降低系統(tǒng)成本，而且更重要的是可以有效提高系統(tǒng)的可靠性。
幾十年的經(jīng)驗(yàn)表明，可靠性好壞是國(guó)產(chǎn)數(shù)控系統(tǒng)能否發(fā)展的關(guān)鍵。雖然影響數(shù)控系統(tǒng)可靠性的因素很多，但過大的硬件規(guī)模和較低的硬件制造工藝水平往往對(duì)可靠性造成最大的威脅。以往，國(guó)產(chǎn)數(shù)控系統(tǒng)在總體設(shè)計(jì)時(shí)由于種種原因的限制，不得不選用技術(shù)指標(biāo)不太高的普通CPU，這樣，為完成數(shù)控的復(fù)雜功能往往需要由多個(gè)CPU來組成系統(tǒng)，有時(shí)還需另加一些專用或通用硬件電路來實(shí)現(xiàn)數(shù)控系統(tǒng)的一些高實(shí)時(shí)性功能（如細(xì)插補(bǔ)、位置伺服控制等），從而造成系統(tǒng)硬件規(guī)模龐大。對(duì)于數(shù)控系統(tǒng)這種批量不大的產(chǎn)品，在國(guó)內(nèi)現(xiàn)有工藝條件下，很難從硬件制造的角度保證系統(tǒng)的可靠性，因而使得國(guó)產(chǎn)數(shù)控系統(tǒng)在生產(chǎn)現(xiàn)場(chǎng)的表現(xiàn)不佳，對(duì)國(guó)產(chǎn)數(shù)控系統(tǒng)的形象和聲譽(yù)造成嚴(yán)重影響，使得不少用戶現(xiàn)在還心有余悸。
因此，我們?cè)陂_發(fā)新型數(shù)控系統(tǒng)時(shí)，應(yīng)優(yōu)先選用新型高性能CPU（如高主頻的Pentium II、Pentium III等）作為系統(tǒng)的運(yùn)算和控制核心，并盡量用軟件來實(shí)現(xiàn)數(shù)控的所有功能。這樣，可大幅度減小系統(tǒng)硬件的規(guī)模。此外，還應(yīng)在軟件設(shè)計(jì)、電源設(shè)計(jì)、接插件設(shè)計(jì)與選用、接地與屏蔽設(shè)計(jì)和施工等方面采用強(qiáng)抗擾高可靠性設(shè)計(jì)與制造技術(shù)，從而全面提高系統(tǒng)的可靠性。
由于一個(gè)新型高性能CPU可以代替數(shù)十個(gè)普通CPU（如80286、80386等），因此，在基于高性能CPU的PC平臺(tái)上不僅可以完成數(shù)控系統(tǒng)的基本功能（如信息處理、刀補(bǔ)計(jì)算、插補(bǔ)計(jì)算、加減速控制等）和開關(guān)量控制功能（內(nèi)裝PLC），而且還可以完成伺服控制功能。這樣，以前由DSP完成的數(shù)字化伺服控制功能（如位置控制、速度控制、矢量變換控制等）均可由PC中的CPU完成，從而實(shí)現(xiàn)內(nèi)裝式伺服控制，這不僅有效縮小了數(shù)控部分的硬件規(guī)模，而且還大幅度縮小了伺服控制部分硬件規(guī)模.這種具有內(nèi)裝PLC和內(nèi)裝伺服控制的全軟件化集成式數(shù)控系統(tǒng)，其硬件規(guī)模將達(dá)到最小化，整個(gè)數(shù)控系統(tǒng)除一個(gè)PC平臺(tái)外，剩下的只有驅(qū)動(dòng)機(jī)床運(yùn)動(dòng)的功率接口和反饋接口。這既有效提高了系統(tǒng)可靠性，又消除了信息傳遞瓶頸，提高了系統(tǒng)性能，同時(shí)還可顯著降低系統(tǒng)成本，使系統(tǒng)（包括電機(jī)）售價(jià)將可降至現(xiàn)有數(shù)控系統(tǒng)的一半左右。顯然，這種高性能、高可靠性、低成本的新型數(shù)控系統(tǒng)將具有極強(qiáng)的競(jìng)爭(zhēng)力，有望為開創(chuàng)中國(guó)數(shù)控的新局面作出貢獻(xiàn)。
此外，集成化PC數(shù)控系統(tǒng)還有一大優(yōu)點(diǎn)，就是容易實(shí)現(xiàn)開放式結(jié)構(gòu)。這是因?yàn)?，這種系統(tǒng)的硬件本身已經(jīng)是完全開放的，構(gòu)成開放式數(shù)控系統(tǒng)的工作完全在軟件上，只要制定好標(biāo)準(zhǔn)和協(xié)議，從信息處理、軌跡插補(bǔ)、加減速控制、開關(guān)量控制到伺服控制都可以實(shí)現(xiàn)開放，從而可大大方便用戶的使用。
2.2 推進(jìn)數(shù)控功能部件的專業(yè)化生產(chǎn)
解決數(shù)控系統(tǒng)問題后，如何實(shí)現(xiàn)數(shù)控機(jī)床的模塊化設(shè)計(jì)與制造便是我國(guó)機(jī)床制造企業(yè)快速響應(yīng)市場(chǎng)需求，在競(jìng)爭(zhēng)中獲勝的另一關(guān)鍵。要實(shí)現(xiàn)數(shù)控機(jī)床的模塊化設(shè)計(jì)制造，必須解決數(shù)控機(jī)床功能部件的專業(yè)化生產(chǎn)問題。目前我國(guó)在這方面離實(shí)際需求還有相當(dāng)大的差距。因此，在今后的若干年內(nèi)，我們必須大力促進(jìn)數(shù)控機(jī)床功能部件的開發(fā)和專業(yè)化生產(chǎn)。其要點(diǎn)如下：
(1)新型永磁電主軸單元 電主軸已成為國(guó)際市場(chǎng)上最熱門的數(shù)控機(jī)床功能部件。但目前這類產(chǎn)品幾乎都為感應(yīng)異步型，存在以下突出問題：①轉(zhuǎn)子上存在繞組，有大電流流過，因此轉(zhuǎn)子發(fā)熱嚴(yán)重，直接影響主軸精度；②低速出力小且轉(zhuǎn)矩脈動(dòng)大，難以滿足寬范圍切削要求；③效率和功率因素低，不僅電機(jī)體積和重量大而且要求逆變器容量大、耗能多；④控制系統(tǒng)復(fù)雜、成本高.因此，利用我國(guó)稀土永磁材料的優(yōu)勢(shì)，開發(fā)新型大功率、高效率、寬調(diào)速范圍永磁同步型交流電主軸單元，將可有效解決現(xiàn)有電主軸存在的問題，形成具有中國(guó)特色的新一代電主軸產(chǎn)品。由于永磁電主軸的機(jī)械結(jié)構(gòu)和控制系統(tǒng)都較感應(yīng)異步型電主軸簡(jiǎn)單，因此易于進(jìn)行專業(yè)化大規(guī)模生產(chǎn)。當(dāng)然，這還要攻克主軸支承（陶瓷軸承、流體動(dòng)靜壓軸承、磁懸浮軸承）技術(shù)、高精度高速動(dòng)平衡技術(shù)、高速驅(qū)動(dòng)、檢測(cè)與控制技術(shù)、高可靠性安全保證技術(shù)等關(guān)鍵技術(shù)。
(2)廉價(jià)的高性能伺服系統(tǒng) 目前，一套進(jìn)給交流伺服系統(tǒng)（驅(qū)動(dòng)器+電機(jī)）的價(jià)格一般都在萬元以上，主軸伺服系統(tǒng)的價(jià)格高達(dá)數(shù)萬元，已成為降低國(guó)產(chǎn)數(shù)控機(jī)床成本的一大障礙。因此，應(yīng)配合新型集成化國(guó)產(chǎn)數(shù)控系統(tǒng)的發(fā)展，大力開發(fā)廉價(jià)的高性能內(nèi)裝式伺服系統(tǒng)。由于內(nèi)裝式伺服的硬件部分只有電機(jī)和功率接口，充分利用我國(guó)的永磁資源優(yōu)勢(shì)，通過專業(yè)化生產(chǎn)可以把電機(jī)的造價(jià)降下來，而采用智能化的IPM模塊作為功率接口也很便宜，因此將內(nèi)裝式進(jìn)給伺服的價(jià)格控制在數(shù)千元以內(nèi)，將內(nèi)裝式主軸伺服的價(jià)格控制在2萬元以內(nèi)，將是完全可能的。
(3)直線交流伺服系統(tǒng) 直線交流伺服系統(tǒng)是下一世紀(jì)數(shù)控機(jī)床不可缺少的功能部件，目前我國(guó)還沒有成熟產(chǎn)品，因此應(yīng)加強(qiáng)研究、開發(fā)和推廣應(yīng)用。考慮到常規(guī)機(jī)床的防磁問題較難解決，而并聯(lián)機(jī)床的防磁相對(duì)容易，因此可為常規(guī)結(jié)構(gòu)機(jī)床開發(fā)感應(yīng)異步型直線電機(jī)，為并聯(lián)結(jié)構(gòu)機(jī)床開發(fā)永磁同步型直線電機(jī)，從而揚(yáng)長(zhǎng)避短，構(gòu)成符合實(shí)際應(yīng)用要求的新型高速高精度進(jìn)給系統(tǒng)。在此基礎(chǔ)上，可進(jìn)一步開發(fā)將驅(qū)動(dòng)與支承合二為一的磁懸浮工作臺(tái)。
(4)零傳動(dòng)數(shù)控轉(zhuǎn)臺(tái)與擺頭 數(shù)控轉(zhuǎn)臺(tái)與擺頭是多坐標(biāo)數(shù)控機(jī)床的關(guān)鍵部件，傳統(tǒng)的采用高精度蝸桿蝸輪等傳動(dòng)的轉(zhuǎn)臺(tái)與擺頭不僅制造難度大、成本高，而且難以達(dá)到高速加工所需的速度和精度，因而必須另辟蹊徑開發(fā)新型零傳動(dòng)（無機(jī)械傳動(dòng)鏈）數(shù)控轉(zhuǎn)臺(tái)和擺頭，以促進(jìn)我國(guó)高速高精度多坐標(biāo)數(shù)控機(jī)床的發(fā)展。
(5)高速高精度檢測(cè)裝置 高速高精度是下世紀(jì)數(shù)控機(jī)床發(fā)展的主題，這不但需要高性能的控制和驅(qū)動(dòng)，同時(shí)還需要高品質(zhì)的檢測(cè)環(huán)節(jié)，因此應(yīng)在現(xiàn)有技術(shù)基礎(chǔ)上，進(jìn)一步開發(fā)0.1 μm以上精度的高速(60 m/min以上)線位移傳感器和100萬脈沖/r的角位移傳感器，此類技術(shù)國(guó)外對(duì)我國(guó)是封鎖的。
2.3 加速數(shù)控機(jī)床的全國(guó)產(chǎn)化，打好市場(chǎng)翻身仗
數(shù)控產(chǎn)業(yè)化的最終成功將體現(xiàn)在數(shù)控機(jī)床的全國(guó)產(chǎn)化和市場(chǎng)占有率上。在上述總體戰(zhàn)略指導(dǎo)下，采取抓兩頭（低價(jià)位數(shù)控機(jī)床和高速高效數(shù)控機(jī)床）、帶中間（普通數(shù)控機(jī)床）、促重型（重型關(guān)鍵裝備）的方針，將是在國(guó)內(nèi)市場(chǎng)上快速收復(fù)失地，在國(guó)際市場(chǎng)上穩(wěn)步進(jìn)軍，最終打贏國(guó)產(chǎn)數(shù)控機(jī)床市場(chǎng)翻身仗的一種有效戰(zhàn)術(shù)和策略。關(guān)于普通數(shù)控機(jī)床的發(fā)展已有許多文章作了專門論述，因此下面僅就低價(jià)位數(shù)控機(jī)床、高速高效數(shù)控機(jī)床和重型數(shù)控機(jī)床的發(fā)展問題作一討論。
附錄B
The Numerical control’s development
The Numerical Control technical and the equipmentis important for the foundation of the modern industry.Whether this foundation affects an economy of nation to develop directly and comprehensive national strength, relate to a strategic position of nation.Therefore, theflourishing nation of each industry all adopts the important measure in the world to develop own number to control technique and its industries.
In our country, the number controled the development of technique and material to also get the high value, obtaining the very big progress in recent years.Count to control the realm in the in general use and tiny machine especially, take terrace of PC as basal domestic the number controls the system, have already walk at ex- row in world.But, the our country is counting to control the technique research and the industry developments to also exist not a few problems, especially creative ability in the technique, commercialize the aspect circumstances, such as progress and market share...etc. is outstanding.At new arrival of century, how resolve these problems effectively, make the our country number control the realm the road of the development, from whole up exceed into advanced row or column in world completely, make us have the prominent position in the international competition, will is a number to control the research development section and produce the factory house face of important mission.In order to co along can keep on mplete this mission, must establish the development road of match the Chinese state of the nation first.For this, this text controls the system, function parts and counts to control the whole machine from the total strategy and two layers of the technique route and numbers etc. a few concrete aspects inquiried into the development path of the new century.
1.total strategy
The establishment matches the total development of the Chinese state of the nation strategy, to 21 centuries our country count control the technique and industries to develop to go to close the importance.Control the analysis that the technique and industries develop the trend through a logarithms and to the research that the our country number control the realm existence problem, we think to take science and technology innovation as to lead first, changing into the lord stem with the merchandise, taking management and marketings as the point, with the technique supports and serves for backing, insist can keep on to develop the road and will is a kind of to match the our country state of the nation to develop number to control the technique and industries of total strategy.
1.1Take science and technology innovation as to lead first
The number in China control technique and industry through more than 40 years of development, from did not have from ushering in to digest to own the independent independent copyright of oneself, obtain the very big progress.But look back this several decades of development, can see us at count to control the progress of the realm to mainly still press a little bit foreign mode, press department a ground development, the real creative composition is not much.This kind of situation is developping the start stage of the initial stage, is not scandalous.But went to the world to count to control the strong hand,such as the wood's today and knowledge-based economy, and will soon ascend the new century of satge, this normal regulations path of the very difficult line.For example, at the abroad imitate servo quick dated, we start make to imitate servo, have not yet wait we share the steady market, having already fallen behind in the technique;At the abroad beat into the numerical type that the pulse drive is servo the our country market, we come after to make this so-called numeral servo, but did not become the big market scale up to now;Foreign develop numerical type is servo to use the network( pass the fiber optic cable etc.) to control with number to equip the conjunction recently, we come after to develop this kind of system again, the prospect is still not optimistic.This kind of always follow at the other people walk behind, press the abroad to already have the control and drive the mode to develop domestic the number controls the system, after technique up difficult do not need to want the chiyi, and foreign company at our country inshore establish the graduate school and produce the factory, practice to develop right on the spot, produce right on the spot and sell right on the spot, make our product at the function price compare up have already had no many big advantages more and more, so want to further extend the market share, difficulty nature very big.
In order to change this kind of present condition, we must get it deeply and the great theory of the earnest implementation" science technique is the first productivity"s break, strengthenning the number to control the science and technology innovation of the realm strongly, diligent the research has the practical forerunner of Chinese special features to count to control the technique, building up the oneself gradually independent, the forerunner's technique system.Develop the number of match the Chinese state of the nation to control the product strongly on this foundation, thus become from the number controls the system and counts to control the function parts to category the well-found number controls the whole machine of tool machine of integrity of industry system.Thus, just will not be led long the nose by the abroad, be check and supervision by the other people forever, just use the forerunner probably, practical of number control the product to recover the local market, open the international market, make China of number control the technique and number control the industry to walk in 21 centuries ex- row in world.
1.2 malicious contrive in commercialize
In the last few years the our country number controls the product although the development is very quick, real at stop the feet on the market of not much.In regard to number control system, domestic goods not yet real were accept by the large tool machine factory, so appear the domestic number to control the example that the system useds for the old tool machine reformation more, but new tool machine of material of but few, the tool machine factory produce domestic the number controls the tool machine to use mostly of is all a foreign system.This of course not is a number that says the old tool machine to control to turn the reformation of no account, but the elucidation sees from the angle of the merchandise, our number controls the system and abroads to compare to still exist the very big margin.
In addition to the technique function and functions, the main factor that affects the number to control the system and numbers to control the tool machine to commercialize is more important is a credibility, stability and function.Before, some numbers control the research, the development section of technique and product, pursue of is usually some bodies the index sign( such as how much passage, how much stalk tit move, every minute how much rice enter to the speed etc.) of the technique level now, but little thought of towards affecting some index signs and some small problems of function but, in the energy of stability, the stick, credibility, the function aspect flower of product opposite less.Thus appear levels for some products to authenticate all very high, even also get various big prize.But the product of these high index sign, high performances arrive customer where do not fulfil person's idea because of some small problems but performance, lost the prestige finally, beat not to open for business the field.This elucidation, the product of the kind model of the high index sign, high performance leaves the customer real the practical and dependable merchandise that need is to have the very big distance of, changing into a product of high index sign, high performance a merchandise that has the market still needs to make a great deal of effort of hardship.
1.4 persistences can keep on to develop the road
The development is a next century the importance that business enterprise development strategy, our country the number controls the industry to want to have the big development and also musts insist to walk and can keep on the road of the development.The green is a realization and can keep on the important path of the development, its main thought is to sweep and economize.For this development that should strengthen the green number to control the product strongly, the acceleration promotes the number control the product and counts to control industry and the whole green of manufacturing industries to turn, the main strategic measure should consider following several aspectses:The ① is valid to reduce the product manufacturing and usage pollution of the environment within process.If reduce the number to control a structure of the tool machine, the cancellation casts the pollution to the environment;Control number to the lubrication of the tool machine principal axis to lubricate, spray the oil lubrication with the oil spirit etc. replaces the oil fog lubrication, reduce to produce environment of pollution;Cancel the cold constant temperature technique of freon system in nicety count control tool machine and it circulate environment of temperature control;Move to replace the machine to spread to move with the fax, reduce a pollution.The ② is significant to lower the resources depletion and energy depletions.Such as replace the hardware with the software, thus reduce the resources and energies of the hardware manufacturing depletion and pollution, and reduce the product life span be over behind the hardware equip of dismantle to unload to recover the problem;Always it drives to replace to respond to drive, lift high-efficiency and the power factor, economize the energy;Move to replace the machine to spread to move with the fax, lift high-efficiency, reduce the energy depletion.The ③ strengthens to control the traditional tool machine of the technique reformation with the number.This since match to make use of the information technique and the automation techniques to reform the traditional industry, make the traditional industry production technique and equip modern this industry and can keep on the target of the development and can carry out, again commendable get huge economic performance.The our country owns the millions set of common tool machine, strengthen to use the number and control the traditional tool machine of the technique reformation and will become next century our country number control important development direction of the realm.The ④ develops the green number to control the tool machine strongly.Green the number control the tool machine and should be a material consume little, can consume low and free from pollution, the life span is long and easy to dismantle new tool machine of unload the recovery.
2 technique paths
2.1 developments have the new generation PC number of Chinese special features to control the system.
The number controls the core that the system is each kind of number to control the material, so control the system through the new number that science and technology innovation develops to have the Chinese special features first, will be valid technique path that pushes number to control the industry to turn the progress.Practice the certificate,10 in the last yearses the PC that we walk the number controls the road is completely right.The PC machine( include the industry PC) yield is big, the price cheapness, the technique progresses to raise with function very quickly, and the credibility is high.Therefore, being the number to control the soft hardware terrace of the system with it not only can with significant raise number to control the function price of the system to compare, but also can also make use of the in general use and tiny machine to already have the last word of the soft hardware resources and the sharing calculator realm well, exchanging such as the colorful display, multi-media information of saving machine, high resolution of big capacity.In addition, be the number to control with the in general use and tiny machine the terrace and can also acquire the fast technique progress, be the PC machine upgrade to change the generation, counting to control the system also can correspond the upgrade to change the generation, thus keeping the advantage on the technique over a long period of time, at compete the neutral in the invincible position.
Currently, the PC number control the system structure of the system contain 2 kinds of main forms:(1)The appropriation number controls compound type structure of add the head of PC;(2)The in general use PC add a controls the card of pass the rank type structure.Still have moreover a kind of just the numeral that develop turns the distribute type structure.Its project is to will be is servo by the numerical type that etc. constitute of DSP to pass with fiber optic cable etc. for lie the quality of network and number control to equip to link, constitute one integrity of number control the system.This kind of system although the function is good very, is too high because of the development and production cost, and is hard to was accept by the local and large customer in the near future.We think that the above-mentioned structure is not the best project that matches the Chinese state of the nation, in keeping with Chinese state of the nation of should be control all numbers the function whole software turn of gather the type structure, because of the hardware scale of this kind of structure minimum, not only be advantageous to lowering the system cost, but also more important can raise dependable sex of the system effectively.
Several decades of experience enunciation, dependable sex quality is the domestic number control can system develop of key.Although affect the number to control the factor of the system credibility a lot of, lead the big hardware
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