喜歡就充值下載吧，，資源目錄下展示的全都有，，下載后全都有，dwg格式的為CAD圖紙，有疑問咨詢QQ：414951605 或1304139763 長春工程學(xué)院 2020屆畢業(yè)設(shè)計(jì)（論文）指導(dǎo)教師資格及題目審批表 指導(dǎo)教師姓名 王利濤 所在單位 機(jī)電學(xué)院 指導(dǎo)教師職稱 副教授 所學(xué)專業(yè) 機(jī)制 設(shè)計(jì)（論文）題目 油泵齒輪壓裝機(jī)設(shè)計(jì) 題 目 類 型 設(shè)計(jì) √ 題 目 來 源 科 研 實(shí)驗(yàn)室建設(shè) 論文 工程生產(chǎn) √ 自 擬 題目真實(shí)性程度 真實(shí) √ 題目新舊 新題 難度 等級(jí) 難 一般 模擬 舊題 √ 較難 √ 設(shè)計(jì)（論文）地點(diǎn) 校內(nèi) √ 設(shè)計(jì)（論文）時(shí)間 自03月 2 日 至06 月12日 校外 題目概要（設(shè)計(jì)（論文）的目的、可行性、技術(shù)路線等）： 本題目來源于吉林長久三美機(jī)械設(shè)備有限公司，機(jī)油泵齒輪壓裝機(jī)設(shè)計(jì)是應(yīng)用專業(yè)知識(shí)完成一臺(tái)自動(dòng)化壓裝設(shè)備設(shè)計(jì)，該設(shè)備用于機(jī)油泵裝配流水線上。通過該設(shè)計(jì)題目，使學(xué)生在設(shè)備總體方案設(shè)計(jì)、機(jī)械結(jié)構(gòu)設(shè)計(jì)、氣液動(dòng)系統(tǒng)設(shè)計(jì)、電控系統(tǒng)設(shè)計(jì)以及零件強(qiáng)度計(jì)算、編寫技術(shù)文件、查閱文獻(xiàn)和設(shè)計(jì)軟件應(yīng)用能力方面受到一次綜合訓(xùn)練，鞏固和綜合運(yùn)用所學(xué)知識(shí)，掌握正確設(shè)計(jì)思想與方法，培養(yǎng)學(xué)生的工程應(yīng)用能力。 機(jī)油泵齒輪壓裝機(jī)需要完成機(jī)油泵主動(dòng)齒輪與軸、從動(dòng)齒輪與軸的壓裝工作，要求工件夾具使用方便可靠、壓裝位置準(zhǔn)確，壓裝力可檢測，工作臺(tái)高度位置可調(diào)以適應(yīng)不同型號(hào)機(jī)油泵齒輪軸總成壓裝，壓裝力可用電機(jī)或氣動(dòng)實(shí)現(xiàn)，工作過程有安全保護(hù)。齒輪與軸的裝配工藝與技術(shù)要求見附件。 技術(shù)路線： （1）壓裝機(jī)總體方案設(shè)計(jì)。 （2）機(jī)械總裝配設(shè)計(jì)、零件詳細(xì)結(jié)構(gòu)設(shè)計(jì)。 （3）氣動(dòng)或電動(dòng)系統(tǒng)設(shè)計(jì)及計(jì)算。 （4）控制部分選型及設(shè)計(jì)。 （5）二維工程圖設(shè)計(jì)與說明書。 成果：設(shè)備總裝配圖（計(jì)算機(jī)出圖）；設(shè)備所有零件圖（計(jì)算機(jī)出圖）；手繪圖A1張；設(shè)計(jì)圖紙數(shù)量不少于3張A0 圖紙；設(shè)計(jì)說明書1.5萬字；譯文與開題報(bào)告不少于3000字. 教研室意見： 教研室主任簽字： 2020年3月 1 日 學(xué)院（系）審查意見： 院長（系主任）簽字： 年 月 日 備注：1.此表由擬擔(dān)任畢業(yè)設(shè)計(jì)（論文）指導(dǎo)工作的教師填寫，每個(gè)題目填報(bào)一張表，一式兩份； 2.部分分項(xiàng)填寫時(shí)，只在對(duì)應(yīng)項(xiàng)內(nèi)打“√”即可； 3.表中真實(shí)題目是指在學(xué)校、生產(chǎn)、科研及其它單位實(shí)際立項(xiàng)的課題； 4.指導(dǎo)教師如果是外聘，應(yīng)在所在單位欄中加注（外聘）字樣； 5.在畢業(yè)設(shè)計(jì)（論文）工作開始前，各院（系）將此表匯總，報(bào)教務(wù)處備案。 油泵齒輪壓裝機(jī)答辯人：黎航導(dǎo)師：王利濤長春工程學(xué)院CONTENTS目 錄01緒 論02工作原理03安全與解決方案04總結(jié)緒 論Thread theory0101選題背景THE BACKGROUND 由于我國工業(yè)基礎(chǔ)溥弱,油泵齒輪行業(yè)起步較慢，雖然其發(fā)展速度比較快。經(jīng)由二十余年消化吸收國外提高前輩技術(shù)以及自主立異。我國油泵齒輪設(shè)備制造行業(yè)也有了奔騰發(fā)展。但相對(duì)于世界上一些工業(yè)發(fā)達(dá)國家而已，我國還是有待提升的，隨著工業(yè)的發(fā)展，壓裝機(jī)也隨著對(duì)工業(yè)技術(shù)的發(fā)展而達(dá)到了一個(gè)理想的工藝范圍。油泵齒輪壓裝機(jī)02研究內(nèi)容與要求 本題目來源于吉林長久三美機(jī)械設(shè)備有限公司，機(jī)油泵齒輪壓裝機(jī)設(shè)計(jì)是應(yīng)用專業(yè)知識(shí)完成一臺(tái)壓裝設(shè)備設(shè)計(jì)，該設(shè)備用于機(jī)油泵裝配流水線上。要求機(jī)油泵齒輪壓裝機(jī)能完成機(jī)油泵主動(dòng)齒輪與軸、從動(dòng)齒輪與軸的壓裝工作，要求工件夾具使用方便可靠、壓裝位置準(zhǔn)確，壓裝力可檢測，工作臺(tái)高度位置可調(diào)以適應(yīng)不同型號(hào)機(jī)油泵齒輪軸總成壓裝，壓裝力可用電機(jī)或氣動(dòng)實(shí)現(xiàn)，工作過程有安全保護(hù)。03研究綜述問題1問題2問題3問題4壓裝精度不高，不能保證油泵齒輪壓裝精度。其對(duì)不同型號(hào)的油泵齒輪壓裝時(shí)，需要人工手動(dòng)更換底盤，生產(chǎn)效率低。人工更換夾具，軸位差很難控制，更難滿足油泵齒輪的生產(chǎn)精度要求。生產(chǎn)效率低，一次壓裝合格率低，壓裝的質(zhì)量受人為影響很大。目前，國內(nèi)一些主要汽車生產(chǎn)廠家使用的油泵齒輪壓裝機(jī)，在設(shè)備上還停留在五，六十年代的水平，結(jié)構(gòu)簡單，性能單一，生產(chǎn)效率低，設(shè)備完全靠人工控制，尺寸精度只能控制在2mm范圍內(nèi)，控制系統(tǒng)落后，手動(dòng)操作，人工檢測，不但人工勞動(dòng)強(qiáng)度大，而且生產(chǎn)效率低。而且還存在以下問題：04壓裝設(shè)備和總體方案設(shè)計(jì)機(jī)械系統(tǒng)主要由壓裝裝置、工件的定位和夾緊裝置、等組成。在壓裝機(jī)升降部分采用導(dǎo)柱來進(jìn)行升降，油泵齒輪在工作臺(tái)面上利用定位夾爪來進(jìn)行夾持，上方軸套通過定位后，由壓裝機(jī)頭透過導(dǎo)套來實(shí)現(xiàn)壓裝作業(yè)工作，側(cè)方傳感器來檢測壓裝工作的強(qiáng)度，完成壓裝過程。05壓裝零件與技術(shù)要求1.滿足工作需求，穩(wěn)定性好結(jié)構(gòu)準(zhǔn)確性高。2.操作調(diào)整方便，設(shè)計(jì)成本不易過高，外觀盡量美觀簡潔。3.齒輪軸定位板，應(yīng)滿足承受軸向力作用。4.夾具定位精度：0.01mm。5.壓裝機(jī)立柱滑動(dòng)部分，直線行程誤差0.01mm。6.壓裝機(jī)重復(fù)壓裝精度：0.01mm。7.壓裝機(jī)上壓板應(yīng)同步下壓。8.保證操作工人的生命安全。工作原理0201夾具部分齒輪定位夾爪壓裝底座壓裝底座立板壓裝底座臺(tái)板夾具部分的工作原理：先將齒輪放置在壓裝底座臺(tái)板的凹陷處，由于附件安裝了光電傳感器，當(dāng)感應(yīng)到放入齒輪后，會(huì)轉(zhuǎn)化為電信號(hào)傳送給氣動(dòng)裝置，氣動(dòng)裝置傳動(dòng)給氣動(dòng)手指，氣動(dòng)手指控制齒輪定位夾爪夾緊齒輪，然后將壓裝軸通過軸套固定在豎直方向。準(zhǔn)備進(jìn)行壓裝工作軸套氣動(dòng)手指02壓裝部分電缸電缸導(dǎo)桿電缸連接板壓裝轉(zhuǎn)接板壓裝軸固定板壓裝軸壓裝部分的工作原理：先按啟動(dòng)按鈕，伺服電機(jī)開始工作，將旋轉(zhuǎn)運(yùn)動(dòng)轉(zhuǎn)化為電缸豎直方向的直線運(yùn)動(dòng)，從而使電缸導(dǎo)桿向下運(yùn)動(dòng)，帶動(dòng)壓裝軸向下運(yùn)動(dòng)，完成壓裝齒輪與軸的工作，而為了確定齒輪在壓裝軸過程中的壓緊力與位移量，在其右側(cè)感應(yīng)器固定板中裝有壓力傳感器和位置傳感器進(jìn)行測量，然后將信息反饋給伺服電機(jī)進(jìn)行調(diào)整，防止出現(xiàn)問題。感應(yīng)器固定板安全與解決方案0301防護(hù)網(wǎng) 在工業(yè)技術(shù)如此發(fā)達(dá)的時(shí)代，我們不僅僅要做到技術(shù)方面的提高，在安全意識(shí)方面，我們也應(yīng)該盡力保證每個(gè)工人的安全，如右圖所示，在壓裝機(jī)兩邊安裝上鋼絲的防護(hù)網(wǎng)，可以有效的避免壓裝過程中設(shè)備出現(xiàn)問題而導(dǎo)致的傷亡事故。例如壓裝時(shí)零件崩斷彈出等。02啟動(dòng)開關(guān)按鈕 為了避免工人在一邊操作機(jī)器一邊啟動(dòng)按鈕的時(shí)候存在的安全隱患，將啟動(dòng)按鈕設(shè)置為兩個(gè)串聯(lián)的開關(guān)，在啟動(dòng)時(shí)需要同時(shí)按下兩個(gè)按鈕才能將設(shè)備啟動(dòng)，這樣就杜絕了工人因?yàn)檎`按按鈕而導(dǎo)致的事故總 結(jié)Summary0401研究總結(jié)STUDY CONCLUDED本次設(shè)計(jì)最后得出的結(jié)果無論是對(duì)工業(yè)產(chǎn)業(yè)的發(fā)展，還是對(duì)安全因素的考慮都是十分重要的。對(duì)裝配設(shè)計(jì)的安裝方面設(shè)計(jì)及控制系統(tǒng)有更深入的了解，同時(shí)對(duì)機(jī)械原理、機(jī)械制圖等專業(yè)知識(shí)有了更全面的掌握。由于知識(shí)方面的不足，因此在選擇傳動(dòng)系統(tǒng)及電氣控制存在著不足，尺寸公差間存在著差異，希望老師們給予批評(píng)和指正。02致謝ACKNOWLEDGEMENTS 大學(xué)的四年學(xué)習(xí)時(shí)光轉(zhuǎn)瞬即逝，我的畢業(yè)設(shè)計(jì)也接近了尾聲。在大學(xué)的最后一年里，經(jīng)過自己的努力，畢業(yè)設(shè)計(jì)的內(nèi)容終于快要完成了，這是對(duì)我大學(xué)四年所學(xué)知識(shí)最好的一次總結(jié)和考驗(yàn)。在沒有開始做畢業(yè)設(shè)計(jì)之前，對(duì)大學(xué)所學(xué)知識(shí)的檢驗(yàn)只有期末考試，但是期末考試只是針對(duì)單一學(xué)科的考核。在做畢業(yè)設(shè)計(jì)之后，我發(fā)現(xiàn)要很好的完成畢業(yè)設(shè)計(jì)的內(nèi)容，需要對(duì)多門學(xué)科的知識(shí)進(jìn)行綜合的應(yīng)用。這種綜合應(yīng)用是對(duì)我所學(xué)知識(shí)的一種綜合的再學(xué)習(xí)以及再提高的過程，這一過程對(duì)我的學(xué)習(xí)能力，獨(dú)立思考，多學(xué)科綜合能力以及工作能力都是一種培養(yǎng)。另外在做畢業(yè)設(shè)計(jì)的過程中，我認(rèn)識(shí)到學(xué)習(xí)是一個(gè)長期積累的過程，大學(xué)學(xué)習(xí)的結(jié)束并不意味著自身專業(yè)知識(shí)學(xué)習(xí)的結(jié)束，而是一個(gè)新的開始。致謝! CHANGCHUN INSTITUTE OF TECHNOLOGY 畢業(yè)設(shè)計(jì)任務(wù)書 論文題目：______油泵齒輪壓裝機(jī)設(shè)計(jì) __ 學(xué)生姓名： 黎航 學(xué)院名稱： 長春工程學(xué)院國際學(xué)院 專業(yè)名稱： 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 班級(jí)名稱： 機(jī)制1646 學(xué) 號(hào)： 1622421616 指導(dǎo)教師： 王利濤 教師職稱: 副教授 學(xué) 歷： 碩士 2020年3月1日 長春工程學(xué)院 畢業(yè)設(shè)計(jì)任務(wù)書 國際學(xué)院 學(xué)院 機(jī)制 專業(yè) 2020 屆 題 目 油泵齒輪壓裝機(jī)設(shè)計(jì) 專業(yè)班級(jí) 機(jī)制1646 學(xué)生姓名 黎航 指導(dǎo)老師 王利濤 任務(wù)書下發(fā)日期 2020-3-2 設(shè)計(jì)截止日期 2020-6-12 難度系數(shù) 較難 畢業(yè)設(shè)計(jì)（論文）的主要內(nèi)容： 本題目來源于吉林長久三美機(jī)械設(shè)備有限公司，機(jī)油泵齒輪壓裝機(jī)設(shè)計(jì)是應(yīng)用專業(yè)知識(shí)完成一臺(tái)壓裝設(shè)備設(shè)計(jì)，該設(shè)備用于機(jī)油泵裝配流水線上。通過該設(shè)計(jì)題目，使學(xué)生在設(shè)備總體方案設(shè)計(jì)、機(jī)械結(jié)構(gòu)設(shè)計(jì)、氣液動(dòng)系統(tǒng)設(shè)計(jì)、電控系統(tǒng)設(shè)計(jì)以及零件強(qiáng)度計(jì)算、編寫技術(shù)文件、查閱文獻(xiàn)和設(shè)計(jì)軟件應(yīng)用能力方面受到一次綜合訓(xùn)練，鞏固和綜合運(yùn)用所學(xué)知識(shí)，掌握正確設(shè)計(jì)思想與方法，培養(yǎng)學(xué)生的工程應(yīng)用能力。 機(jī)油泵齒輪壓裝機(jī)能完成機(jī)油泵主動(dòng)齒輪與軸、從動(dòng)齒輪與軸的壓裝工作，要求工件夾具使用方便可靠、壓裝位置準(zhǔn)確，壓裝力可檢測，工作臺(tái)高度位置可調(diào)以適應(yīng)不同型號(hào)機(jī)油泵齒輪軸總成壓裝，壓裝力可用電機(jī)或氣動(dòng)實(shí)現(xiàn)，工作過程有安全保護(hù)。 畢業(yè)設(shè)計(jì)（論文）的主要要求: 設(shè)計(jì)完成 （1）機(jī)油泵齒輪壓裝機(jī)總體方案設(shè)計(jì)；（2）機(jī)械總裝配設(shè)計(jì)、零件詳細(xì)結(jié)構(gòu)設(shè)計(jì)；（3）氣動(dòng)或電動(dòng)系統(tǒng)設(shè)計(jì)及計(jì)算；（4）控制部分選型及設(shè)計(jì)（選作）。 設(shè)計(jì)要求： （1齒輪軸定位板應(yīng)滿足承受軸向力作用;（2）夾具定位精度≤0.01 mm ;（3）壓裝機(jī)立柱滑動(dòng)部分直線行程誤差≤0.0lmm;（4）壓裝機(jī)重復(fù)壓裝精度≤0.0lmm;（5）壓裝機(jī)上壓板應(yīng)同步下壓；（6）保證操作工人的生命安全； 齒輪與軸的裝配工藝與技術(shù)要求文件見附件。 設(shè)備總裝配圖（計(jì)算機(jī)出圖）；設(shè)備所有零件圖（計(jì)算機(jī)出圖）；手繪圖A1張；設(shè)計(jì)圖紙數(shù)量不少于3張A0 圖紙；設(shè)計(jì)說明書1.5萬字；譯文與開題報(bào)告不少于3000字； 主要參考文獻(xiàn)： [1]吳忠澤.機(jī)械設(shè)計(jì).北京：高等教育出版社.2006. [2]何忠保，陳曉華，王秀英.典型零件圖冊.北京：機(jī)械工業(yè)出版社.2000. [3] 胡宗武《非標(biāo)準(zhǔn)機(jī)械設(shè)備設(shè)計(jì)手冊》機(jī)械工業(yè)出版社.北京： 2005. [4]機(jī)械原理 蒲良貴.機(jī)械原理 .北京：高等教育出版社.2011. 任務(wù)書編制教師（簽章）： 2020年 3 月1日 教研室審核意見: 教研室主任(簽章): 2020 年 3 月 1 日 學(xué)院審核意見: 學(xué)院院長(簽章): 年 月 日 備注 注：任務(wù)書中的數(shù)據(jù)、圖表及其他文字說明可作為附件附在任務(wù)書后面，并在主要要求中標(biāo)明：“見附件” CHANGCHUN INSTITUTE OF TECHNOLOGY 開題報(bào)告 設(shè)計(jì)題目： 油泵齒輪壓裝機(jī) 學(xué)生姓名： 黎航 學(xué)院名稱： 國際教育學(xué)院 專業(yè)名稱： 機(jī)械設(shè)計(jì)制造及自動(dòng)化 班級(jí)名稱： 機(jī)制1646 學(xué) 號(hào)： 1622421616 指導(dǎo)教師： 王利濤 教師職稱: 副教授 學(xué) 歷： 碩士 2020年 03 月 15 日 １、課題論證 1.1課題研究的目的與意義 由于我國工業(yè)基礎(chǔ)溥弱,油泵齒輪行業(yè)起步較慢，但其發(fā)展速度比較快。經(jīng)由二十余年消化吸收國外提高前輩技術(shù)以及自主立異。我國油泵齒輪設(shè)備制造行業(yè)有了奔騰發(fā)展。 油泵齒輪是依靠泵缸與嚙合齒輪間所形成的工作容積變化和移動(dòng)來輸送液體或使之增壓的回轉(zhuǎn)泵。由兩個(gè)齒輪、泵體與前后蓋組成兩個(gè)封閉空間，當(dāng)齒輪轉(zhuǎn)動(dòng)時(shí)，齒輪脫開側(cè)的空間的體積從小變大，形成真空，將液體吸入，齒輪嚙合側(cè)的空間的體積從大變小，而將液體擠入管路中去。吸入腔與排出腔是靠兩個(gè)齒輪的嚙合線來隔開的。油泵齒輪的排出口的壓力完全取決于泵出處阻力的大小。齒輪油泵由獨(dú)立的電機(jī)驅(qū)動(dòng)，有效地阻斷上游的壓力脈動(dòng)及流量波動(dòng)。 在化工和石油部門的生產(chǎn)中,原料、半成品和成品大多是液體,而將原料制成半成品和成品,需要經(jīng)過復(fù)雜的工藝過程,泵在這些過程中起到了輸送液體和提供化學(xué)反應(yīng)的壓力流量的作用,此外,在很多裝置中還用泵來調(diào)節(jié)溫度。在船舶制造工業(yè)中,每艘遠(yuǎn)洋輪上所用的泵一般在百臺(tái)以上,其類型也是各式各樣的。其它如城市的給排水、蒸汽機(jī)車的用水、機(jī)床中的潤滑和冷卻、紡織工業(yè)中輸送漂液和染料、造紙工業(yè)中輸送紙漿,以及食品工業(yè)中輸送牛奶和糖類食品等,都需要有大量的泵。?在農(nóng)業(yè)生產(chǎn)中,泵是主要的排灌機(jī)械。我國農(nóng)村幅原廣闊,每年農(nóng)村都需要大量的泵,一般來說農(nóng)用泵占泵總產(chǎn)量一半以上。在礦業(yè)和冶金工業(yè)中,泵也是使用最多的設(shè)備。礦井需要用泵排水,在選礦、冶煉和軋制過程中,需用泵來供水洗等。在電力部門,核電站需要核主泵、二級(jí)泵、三級(jí)泵、熱電廠需要大量的鍋爐給水泵、冷凝水泵、循環(huán)水泵和灰渣泵等。在國防建設(shè)中,飛機(jī)襟翼、尾舵和起落架的調(diào)節(jié)、軍艦和坦克炮塔的轉(zhuǎn)動(dòng)、潛艇的沉浮等都需要用泵。高壓和有放射性的液體,有的還要求泵無任何泄漏等.?？傊?無論是飛機(jī)、火箭、坦克、潛艇、還是鉆井、采礦、火車、船舶,或者是日常的生活,到處都需要用泵,到處都有泵在運(yùn)行。正是這樣,所以把泵列為通用機(jī)械,它是機(jī)械工業(yè)中的一類重要產(chǎn)品。 而在泵在安裝過程中，我們要用到壓裝機(jī)，它也是泵在制造過程中不可或缺的一部分，而我此次的任務(wù)就是完成油泵齒輪壓裝機(jī)的設(shè)計(jì)，在任務(wù)開始之前，我們得先了解油泵齒輪壓裝機(jī)的設(shè)計(jì)原則： 1 工作可靠 可靠的操作意味著它通常可以在其壽命范圍內(nèi)發(fā)揮其功能。每個(gè)部件必須具有裝置內(nèi)的某些功能，一些主要部件在裝置的正常操作中起決定性作用。機(jī)器零件的設(shè)計(jì)應(yīng)在機(jī)構(gòu)設(shè)計(jì)系統(tǒng)中進(jìn)行需要通過科學(xué)設(shè)計(jì)來確保機(jī)器零件的可靠性。經(jīng)營者必須在勞動(dòng)力范圍內(nèi)，其作業(yè)如果沒有環(huán)境污染、小容量、安全性、便利的整備、環(huán)境的變化等，則必須簡單。 2 便于加工裝配 ????機(jī)器零件縮短制造周期，提高企業(yè)響應(yīng)速度，提高企業(yè)競爭力，降低成本。 3 經(jīng)濟(jì)性好 ?在滿足客戶要求的情況下盡量降低加工費(fèi)用。 4 符合有關(guān)標(biāo)準(zhǔn) ????在設(shè)計(jì)過程中，我們必須遵守國家的法令，如標(biāo)準(zhǔn)、專利法、商標(biāo)法等，盡量提高產(chǎn)品質(zhì)量，合理簡化品種，縮短設(shè)計(jì)和制造周期，降低制造成本，保護(hù)環(huán)境。 1.2文獻(xiàn)綜述（相關(guān)課題國內(nèi)外研究的現(xiàn)狀） 目前，國內(nèi)一些主要汽車生產(chǎn)廠家使用的油泵齒輪壓裝機(jī)，在設(shè)備上還停留在五，六十年代的水平，結(jié)構(gòu)簡單，性能單一，生產(chǎn)效率低，設(shè)備完全靠人工控制，尺寸精度只能控制在2mm范圍內(nèi)，控制系統(tǒng)落后，手動(dòng)操作，人工檢測，不但人工勞動(dòng)強(qiáng)度大，而且生產(chǎn)效率低。壓裝精度不高，如何保證油泵齒輪壓裝精度，這是目前國內(nèi)外的研究設(shè)計(jì)人員思考的問題。再有，其對(duì)不同型號(hào)的油泵齒輪壓裝時(shí)，需要人工手動(dòng)更換底盤，生產(chǎn)效率低。這樣的壓裝延用了很多年，毫無大的改進(jìn)，這種壓裝機(jī)的最大缺點(diǎn)是人工更換夾具，軸位差很難控制，更難滿足油泵齒輪的生產(chǎn)過程中的精度要求，且生產(chǎn)效率低，一次壓裝合格率低，壓裝的質(zhì)量受人為影響很大。鑒于以上各點(diǎn)，得出結(jié)論，此類型油泵齒輪壓裝設(shè)備已不能滿足生產(chǎn)人員對(duì)油泵齒輪壓裝的過程和結(jié)果的最基本要求，還待進(jìn)行設(shè)備更新。 1.3課題研究的內(nèi)容、總體方案及技術(shù)路線、進(jìn)度安排等 研究內(nèi)容： 通過本次設(shè)計(jì)題目，使學(xué)生在設(shè)備總體方案設(shè)計(jì)、機(jī)械結(jié)構(gòu)設(shè)計(jì)、氣液動(dòng)系統(tǒng)設(shè)計(jì)、電控系統(tǒng)設(shè)計(jì)以及零件強(qiáng)度計(jì)算、編寫技術(shù)文件、查閱文獻(xiàn)和設(shè)計(jì)軟件應(yīng)用能力方面受到一次綜合訓(xùn)練，鞏固和綜合運(yùn)用所學(xué)知識(shí)，掌握正確設(shè)計(jì)思想與方法，培養(yǎng)學(xué)生的工程應(yīng)用能力。 油泵齒輪壓裝機(jī)能完成主動(dòng)齒和從動(dòng)齒與軸的壓裝工作，以保證工作效率的提高。壓裝位置準(zhǔn)確，壓裝力可檢測，工作臺(tái)高度位置可調(diào)以適應(yīng)不同型號(hào)油泵齒輪壓裝，壓裝力可用電機(jī)或氣動(dòng)實(shí)現(xiàn)，工作過程有安全保護(hù)。 總體方案： 　　根據(jù)現(xiàn)在市場的情況，油泵齒輪壓裝機(jī)一般為立式壓裝結(jié)構(gòu)，采用上壓下裝的設(shè)計(jì)方式，通過電機(jī)帶動(dòng)壓缸向下運(yùn)動(dòng)進(jìn)行壓裝，下部分則固定好被壓裝零件，從而完成壓裝工作。其中機(jī)械系統(tǒng)主要由壓裝裝置、工件的定位和夾緊裝置、等組成。在壓裝機(jī)升降部分采用導(dǎo)柱來進(jìn)行升降，提升功能有兩個(gè)優(yōu)點(diǎn)。一是提高沖壓安裝效率。壓板安裝機(jī)不僅可以按壓油泵的齒輪組件，而且形狀很大，但也可以完成對(duì)具有低精度要求的若干工件的壓板安裝。壓入部件的尺寸通常非常小，匹配對(duì)環(huán)的高度也非常低，減少頭的移動(dòng)的距離很長。位移提升單元可以適當(dāng)?shù)乜焖僬{(diào)整壓力頭，并且可以大大提高沖壓安裝效率。第二是克服沖床支架的缺點(diǎn)，降低壓床精度。油泵齒輪在工作臺(tái)面上利用定位夾爪來進(jìn)行夾持，上方軸套通過定位后，由壓裝機(jī)頭透過導(dǎo)套來實(shí)現(xiàn)壓裝作業(yè)工作，側(cè)方傳感器來檢測壓裝工作的強(qiáng)度，完成壓裝過程。 技術(shù)路線： 1、滿足工作需求，穩(wěn)定性好結(jié)構(gòu)準(zhǔn)確性高。 2、操作調(diào)整方便，設(shè)計(jì)成本不易過高，外觀盡量美觀簡潔。 3、應(yīng)滿足承受軸向力作用，齒輪軸定位板。 4、夾具定位精度：≤0.01mm。 5、直線行程誤差≤0.01mm，壓裝機(jī)立柱滑動(dòng)部分。 6、壓裝機(jī)重復(fù)壓裝精度：≤0.01mm。 7、壓裝機(jī)上壓板應(yīng)同步下壓。 8、保證操作工人的生命安全。 進(jìn)度安排： 　 時(shí)間 　　　　　　　　　　　　設(shè)計(jì)任務(wù)及要求 第1周 去圖書館找相關(guān)的書籍并進(jìn)行分析、查閱資料，熟悉設(shè)備技術(shù)要求、背景，學(xué)習(xí)與畢業(yè)設(shè)計(jì)相關(guān)知識(shí)，做好前期準(zhǔn)備工作。 第2周 上網(wǎng)搜索相關(guān)論文，報(bào)告，期刊等，做到熟悉自己設(shè)計(jì)的設(shè)備具體內(nèi)容，撰寫開題報(bào)告和外文翻譯，準(zhǔn)備開題報(bào)告答辯PPT。 第3周 進(jìn)行總體方案設(shè)計(jì)，計(jì)算壓裝，傳動(dòng)等壓裝機(jī)與有關(guān)各個(gè)方面的計(jì)算。 第4周 對(duì)壓裝機(jī)結(jié)構(gòu)進(jìn)行設(shè)計(jì)，設(shè)計(jì)壓裝機(jī)整體結(jié)構(gòu)尺寸，計(jì)算并校核壓裝機(jī)的尺寸，保證并確定每個(gè)零件的尺寸大小。 第5周 開始進(jìn)行外購件的選型廠家等。 第6周 先進(jìn)行壓裝機(jī)機(jī)架部分的三維設(shè)計(jì)，并歸類好零件。 第7周 進(jìn)行壓裝機(jī)壓裝部分的三維設(shè)計(jì)，并整理好零件。 第8周 進(jìn)行壓裝機(jī)夾具部分的三維設(shè)計(jì)，并整理好零件歸類。 第9周 進(jìn)行壓裝機(jī)升降部分的三維設(shè)計(jì)，并歸類零件。 第10周 將壓裝裝機(jī)各個(gè)部分進(jìn)行裝配得到完整壓裝機(jī)三維結(jié)構(gòu)，并得出工程圖交由老師審核，進(jìn)行修改。 第11周 編寫設(shè)計(jì)說明書。 第12周 編寫設(shè)計(jì)說明書。 第13周 編寫設(shè)計(jì)說明書，交由老師審核并進(jìn)行修改。 第14周 制作答辯提綱，設(shè)計(jì)定稿，打印，準(zhǔn)備畢業(yè)設(shè)計(jì)答辯。 第15周 進(jìn)行畢業(yè)設(shè)計(jì)答辯。 1.4注意存在的問題 1. 首先要保證人工操作時(shí)的人身安全，保證工人的安全為首要注意問題，要保證工人在開啟機(jī)器，運(yùn)行機(jī)器，關(guān)閉機(jī)器時(shí)，機(jī)器一直處于安全狀態(tài)，要將人的安全放在首位。 2. 其次是非常重要的環(huán)保問題，設(shè)計(jì)時(shí)一定要注意符合綠色環(huán)保的標(biāo)準(zhǔn)，盡量減少對(duì)大自然環(huán)境的污染。 　　 3. 壓裝部分采用氣缸的結(jié)構(gòu)，對(duì)結(jié)構(gòu)密封性，精度要求比較高，裝配過程也比較大，壓裝機(jī)結(jié)構(gòu)有待進(jìn)一步改善。 4. 油泵齒輪與軸之間屬于過盈配合，靠手工難以裝配，即使借助于專用夾具也很難準(zhǔn)確、可靠的定位。 5.在整個(gè)壓裝過程中，很難保證零件已加工表面的質(zhì)量，這就保證不了產(chǎn)品的質(zhì)量。 1.5參考文獻(xiàn) [1] 徐灝. 機(jī)械設(shè)計(jì)手冊[M] 第（三、四、五）冊．北京：機(jī)械工業(yè)出版 [2] 何忠保，陳曉華，王秀英．典型零件圖冊．北京：機(jī)械工業(yè)出版社， 2000 . [3] 胡宗武《非標(biāo)準(zhǔn)機(jī)械設(shè)備設(shè)計(jì)手冊 》 機(jī)械工業(yè)出版社．北京： 2005 . [4] 機(jī)械原理蒲良貴．機(jī)械原理．北京：高等教育出版社 2011 . [5] 吳忠澤 機(jī)械設(shè)計(jì) 北京；高等教育出版社2006 徐灝. 機(jī)械設(shè)計(jì)手冊[M] 第（三、四、五）冊．北京：機(jī)械工業(yè)出版 2、答辯組論證結(jié)論 （1）方案可行，技術(shù)路線清晰 □ （2）方案可行，技術(shù)路線基本清晰 □ （3）方案基本可行，技術(shù)路線不很清晰 □ （4）方案和技術(shù)路線不很清晰 □ （5）方案和技術(shù)路線不清晰 □ 3、指導(dǎo)教師意見： 教研室主任意見： 指導(dǎo)教師（簽名）： 王利濤 教研室主任（簽名）： 2020年 06 月 04 日 年 月 日 注：(1) 開題報(bào)告是用文字體現(xiàn)的設(shè)計(jì)（論文）總構(gòu)想，篇幅不必過大，但要把計(jì)劃設(shè)計(jì)的課題、如何設(shè)計(jì)、理論依據(jù)和研究現(xiàn)狀等主要問題說清楚； (2) 字?jǐn)?shù)不少于3000字，參考文獻(xiàn)不少于6篇，印刷字符在10萬印刷符以上。 油泵齒輪壓裝機(jī)PROFESSIONAL POWERPOINT TEMPLATE姓名:黎航|導(dǎo)師:王利濤01|研究背景及意義02|論文綜述03|研究過程及方法CONTENTS目錄研究背景及意義Part 01研究背景及意義由于我國工業(yè)基礎(chǔ)溥弱,油泵齒輪行業(yè)起步較慢，但其發(fā)展速度比較快。經(jīng)由二十余年消化吸收國外提高前輩技術(shù)以及自主立異。我國油泵齒輪設(shè)備制造行業(yè)有了奔騰發(fā)展。油泵齒輪是依靠泵缸與嚙合齒輪間所形成的工作容積變化和移動(dòng)來輸送液體或使之增壓的回轉(zhuǎn)泵。由兩個(gè)齒輪、泵體與前后蓋組成兩個(gè)封閉空間，當(dāng)齒輪轉(zhuǎn)動(dòng)時(shí)，齒輪脫開側(cè)的空間的體積從小變大，形成真空，將液體吸入，齒輪嚙合側(cè)的空間的體積從大變小，而將液體擠入管路中去。吸入腔與排出腔是靠兩個(gè)齒輪的嚙合線來隔開的。油泵齒輪的排出口的壓力完全取決于泵出處阻力的大小。齒輪油泵由獨(dú)立的電機(jī)驅(qū)動(dòng)，有效地阻斷上游的壓力脈動(dòng)及流量波動(dòng)。45%論文綜述Part 02論文綜述4目前，國內(nèi)一些主要汽車生產(chǎn)廠家使用的油泵齒輪壓裝機(jī)，在設(shè)備上還停留在五，六十年代的水平，結(jié)構(gòu)簡單，性能單一，生產(chǎn)效率低，設(shè)備完全靠人工控制，尺寸精度只能控制在2mm范圍內(nèi)，控制系統(tǒng)落后，手動(dòng)操作，人工檢測，不但人工勞動(dòng)強(qiáng)度大，而且生產(chǎn)效率低。壓裝精度不高，如何保證油泵齒輪壓裝精度，這是目前國內(nèi)外的研究設(shè)計(jì)人員思考的問題。再有，其對(duì)不同型號(hào)的油泵齒輪壓裝時(shí)，需要人工手動(dòng)更換底盤，生產(chǎn)效率低。這樣的壓裝延用了很多年，毫無大的改進(jìn)，這種壓裝機(jī)的最大缺點(diǎn)是人工更換夾具，軸位差很難控制，更難滿足油泵齒輪的生產(chǎn)過程中的精度要求，且生產(chǎn)效率低，一次壓裝合格率低，壓裝的質(zhì)量受人為影響很大。鑒于以上各點(diǎn)，得出結(jié)論，此類型油泵齒輪壓裝設(shè)備已不能滿足生產(chǎn)人員對(duì)油泵齒輪壓裝的過程和結(jié)果的最基本要求，還待進(jìn)行設(shè)備更新。2研究過程及方法Part 03研究內(nèi)容通過本次設(shè)計(jì)題目，使學(xué)生在設(shè)備總體方案設(shè)計(jì)、機(jī)械結(jié)構(gòu)設(shè)計(jì)、氣液動(dòng)系統(tǒng)設(shè)計(jì)、電控系統(tǒng)設(shè)計(jì)以及零件強(qiáng)度計(jì)算、編寫技術(shù)文件、查閱文獻(xiàn)和設(shè)計(jì)軟件應(yīng)用能力方面受到一次綜合訓(xùn)練，鞏固和綜合運(yùn)用所學(xué)知識(shí)，掌握正確設(shè)計(jì)思想與方法，培養(yǎng)學(xué)生的工程應(yīng)用能力。油泵齒輪壓裝機(jī)能一次性完成主動(dòng)齒和從動(dòng)齒與軸的壓裝工作，以保證工作效率的提高。壓裝位置準(zhǔn)確，壓裝力可檢測，工作臺(tái)高度位置可調(diào)以適應(yīng)不同型號(hào)油泵齒輪壓裝，壓裝力可用電機(jī)或氣動(dòng)實(shí)現(xiàn)，工作過程有安全保護(hù)?？傮w發(fā)案Six StepsProcess根據(jù)現(xiàn)在市場的情況，油泵齒輪壓裝機(jī)一般為立式壓裝結(jié)構(gòu)，采用上壓下裝的設(shè)計(jì)方式，通過電機(jī)帶動(dòng)壓缸向下運(yùn)動(dòng)進(jìn)行壓裝，下部分則固定好被壓裝零件，從而完成壓裝工作。其中機(jī)械系統(tǒng)主要由壓裝裝置、工件的定位和夾緊裝置、等組成。在壓裝機(jī)升降部分采用導(dǎo)柱來進(jìn)行升降，提升功能有兩個(gè)優(yōu)點(diǎn)。一是提高沖壓安裝效率。壓板安裝機(jī)不僅可以按壓油泵的齒輪組件，而且形狀很大，但也可以完成對(duì)具有低精度要求的若干工件的壓板安裝。壓入部件的尺寸通常非常小，匹配對(duì)環(huán)的高度也非常低，減少頭的移動(dòng)的距離很長。位移提升單元可以適當(dāng)?shù)乜焖僬{(diào)整壓力頭，并且可以大大提高沖壓安裝效率。第二是克服沖床支架的缺點(diǎn)，降低壓床精度。油泵齒輪在工作臺(tái)面上利用定位夾爪來進(jìn)行夾持，上方軸套通過定位后，由壓裝機(jī)頭透過導(dǎo)套來實(shí)現(xiàn)壓裝作業(yè)工作，側(cè)方傳感器來檢測壓裝工作的強(qiáng)度，完成壓裝過程。技術(shù)路線1.滿足工作需求，穩(wěn)定性好結(jié)構(gòu)準(zhǔn)確性高。2.操作調(diào)整方便，設(shè)計(jì)成本不易過高，外觀盡量美觀簡潔。3.應(yīng)滿足承受軸向力作用，齒輪軸定位板。4.夾具定位精度：0.01mm。5.直線行程誤差0.01mm，壓裝機(jī)立柱滑動(dòng)部分。6.壓裝機(jī)重復(fù)壓裝精度：0.01mm。7.壓裝機(jī)上壓板應(yīng)同步下壓。8.保證操作工人的生命安全。致謝語 大 義 之 方，論 萬 物 之 理 。受 益 終 身!T H A N K S長春工程學(xué)院 畢業(yè)設(shè)計(jì)（論文）開題報(bào)告審核表 指導(dǎo)教師姓名 王利濤 所在單位 國際教育學(xué)院 指導(dǎo)教師職稱 副教授 所學(xué)專業(yè) 機(jī)械設(shè)計(jì)制造及自動(dòng)化 學(xué) 生 姓 名 黎航 班 級(jí) 機(jī)制1646 設(shè)計(jì)（論文）題目 油泵齒輪壓裝機(jī) 指導(dǎo)教師審查 意見 指導(dǎo)教師簽字：王利濤 2020 年 06 月 04 日 教研室審查意見 教研室主任簽字： 年 月 日 學(xué)院審查意見 院長簽字： 年 月 日 CHANGCHUN INSTITUTE OF TECHNOLOGY 油泵齒輪壓裝機(jī)設(shè)計(jì) 設(shè)計(jì)題目： 油泵齒輪壓裝機(jī)設(shè)計(jì) 學(xué)生姓名： 黎航 學(xué)院名稱： 國際教育學(xué)院 專業(yè)名稱： 機(jī)械設(shè)計(jì)制造及自動(dòng)化 班級(jí)名稱： 機(jī)制1646 學(xué) 號(hào)： 1622421616 指導(dǎo)教師： 王利濤 教師職稱： 副教授 完成時(shí)間： 2019.03.04-2019.05.31 2019年5月31日 畢業(yè)設(shè)計(jì)（論文） 油泵齒輪壓裝機(jī)設(shè)計(jì) Design of Press Mounting Machine for Oil Pump Gear 學(xué)生姓名： 黎航 學(xué)歷層次： 本 科 所在院系： 國際教育學(xué)院 所學(xué)專業(yè)： 機(jī)械設(shè)計(jì)制造及自動(dòng)化 指導(dǎo)教師： 王利濤 教師職稱： 副教授 完成時(shí)間： 2019.05.31 長 春 工 程 學(xué) 院 Liand Hao Chin. J. Mech. Eng. (2019) 32:54 https:/doi.org/10.1186/s10033-019-0369-zORIGINAL ARTICLEOn Generating Expected Kinetostatic Nonlinear Stiffness Characteristics bytheKinematic Limb-Singularity ofaCrank-Slider Linkage withSpringsBaokun Li1 and Guangbo Hao2*Abstract Being different from avoidance of singularity of closed-loop linkages, this paper employs the kinematic singularity to construct compliant mechanisms with expected nonlinear stiffness characteristics to enrich the methods of compli-ant mechanisms synthesis. The theory for generating kinetostatic nonlinear stiffness characteristic by the kinematic limb-singularity of a crank-slider linkage is developed. Based on the principle of virtual work, the kinetostatic model of the crank-linkage with springs is established. The influences of spring stiffness on the toque-position angle relation are analyzed. It indicates that corresponding spring stiffness may generate one of four types of nonlinear stiffness characteristics including the bi-stable, local negative-stiffness, zero-stiffness or positive-stiffness when the mechanism works around the kinematic limb-singularity position. Thus the compliant mechanism with an expected stiffness characteristic can be constructed by employing the pseudo rigid-body model of the mechanism whose joints or links are replaced by corresponding flexures. Finally, a tri-symmetrical constant-torque compliant mechanism is fabricated, where the curve of torque-position angle is obtained by an experimental testing. The measurement indicates that the compliant mechanism can generate a nearly constant-torque zone.Keywords: Kinematic singularity, Mechanism with springs, Kinetostatic model, Nonlinear stiffness The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http:/creat iveco mmons .org/licen ses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.1 IntroductionA mechanism with springs is defined as a rigid-body linkage whose joints are placed springs. For this type of mechanisms, the kinetostatic driving force/torque of this type of mechanisms is nonlinear with respect to the position parameter. The nonlinear relation between the driving force/torque and the position parameter is called kinetostatic nonlinear stiffness characteristic. The mech-anism with springs possessing this characteristic can be applied in constant force mechanism 1, vibration isola-tor 2 and gravity balancer 3. The mechanism attached springs is often used in the type synthesis of compli-ant mechanisms based on the rigid-body replacement method and the compliant mechanisms analysis based on the pseudo-rigid-body model 46. Compliant mecha-nisms can be fabricated in monolithic and are applied in many applications needing high precision because of absence of backlash and friction 7, such as energy har-vester based on buckled beam 8, 9, micro-switch 10 and high accurate driver 11. However, the buckled beam only generates bi-stability but other nonlinear stiff-ness characteristics. Moreover, the mechanical model of bi-stable buckled beam is very complicated 12, 13. The four-bar linkage with placed springs can be used to design compliant mechanisms with bi-stable behavior by employing pseudo-rigid-body replacement 14, which develops the configuration of the bi-stable mechanism.When the rigid-body replacement method is use to synthesize compliant mechanisms processing corre-sponding performance, designers should grasp series of performances of the rigid-body linkage. Thus one should have much experience on linkage design and Open AccessChinese Journal of Mechanical Engineering*Correspondence: G.Haoucc.ie 2 School of Engineering, University College Cork, Cork T12K8AF, IrelandFull list of author information is available at the end of the articlePage 2 of 16Liand Hao Chin. J. Mech. Eng. (2019) 32:54 performance analysis. Therefore, it is meaningful that some common attributes are used to construct compliant mechanisms with nonlinear stiffness characteristic.Kinematic singularity which is a basic property of link-ages affects the performance of linkages seriously, so many scholars pay much attention on singularity distri-bution, singularity property identification and singular-ity avoidance 15, 16. However, kinematic singularity has two sides, and can be used to construct new types of devices. Kinematic singularity of the spatial parallel link-age whose links are connected by universal joints are used to construct several types of reconfigurable parallel mech-anisms 17. When parallel mechanisms work near the singularity, they are sensitive to external load. This prop-erty is applied to design the force sensors 18, 19. A new compliant mechanism with negative-stiffness characteris-tic is synthesized by using kinematic singularity of a four-bar linkage 20. The planar parallelogram linkage when the two cranks are collinear is used to construct a type of reconfigurable compliant gripper by applying rigid-body replacement method 21. A new medical device is designed by using the property that a parallel mechanism obtains an additional freedom when it is singular 22.In this paper, by the crank-slider mechanism with springs as an example, the kinematic limb-singularity which is a common property of rigid-body linkages, is used to con-struct the kinetostatic nonlinear stiffness characteristic. The rest of the paper is organized as follows: Section2 addresses the kinetostatic model of the mechanism and Section 3 classifies nonlinear stiffness characteristics as four types. Section4 analyzes the influences of spring stiff-ness on the nonlinear stiffness characteristics generated by the mechanism when moves from nonsingular position and passes the kinematic limb-singularity position. Sec-tion5 indicates that the mechanism only produces posi-tive-stiffness characteristic when moves from the kinematic limb-singularity position to nonsingular position. Section6 describes the approach by creating an expected zero-stiff-ness (constant-torque) characteristic of the mechanism working around the kinematic limb-singularity position. In Section7, design of a nonlinear compliant mechanism is further discussed and is validated by the experimental test-ing. Finally, Section8 draws some important conclusions.2 Kinetostatic Model oftheMechanismFigure 1 shows the schematic of the crank-slider mechanism with springs. Crank AB rotates about pin joint A in anticlockwise and drives the slider to moves along the horizontal line, where link AB and slider are connected by coupler BC. Three pin joints are placed torsional springs whose stiffness is KRA, KRB and KRC, respectively. Prismatic joint C is added extension spring whose stiffness is KPC.The Cartesian coordinates system, O-xyz, is attached on the base, where origin O is fixed on point A, the pos-itive direction of x-axis points to the horizontal right, the positive direction of y-axis is vertically up, and z-axis is determined by the right-hand rule.Vectors AB and BC are defined by r1 and r2, respec-tively. Projects of vector position C on the x-axis and y-axis with respect to the frame O-xyz are defined by r3 and e, respectively. Scalars r1 and r2 are lengths of links AB and BC, respectively. Scalars r3 and e are the coor-dinates of point C on the x-axis and y-axis, respectively. Link-length, r1 and r2, and offset, e, should satisfyso as to allow the mechanism to pass through the right limiting position, which is called the kinematic limb-sin-gularity and occurs when the crank and coupler are along the same line.Here we suppose that there is no friction and clear-ance between any two links connected by a kinematic pair. Moreover, we only discuss the kinetostatic model of the mechanism during the motion rather than con-sidering any inertial force/torque and gravity caused by links quality.The driving torque applied on link AB is set aswhere vector k is the unit vector of z-axis (vectors i and j are unit vectors of x-axis and y-axis, respectively). Torque vector Td is along the z-axis, scalar |Td| is the magni-tude of driving torque Td, where Td 0 indicates Td is along the positive direction of z-axis and Td 0 corre-sponds to direction of Td pointing to negative z-axis.The angular displacement of pin joint A iswhere A is the rotation angle of x-axis to link AB and indicates the input position angle of link AB, A0 cor-responds to the initial angle. In this paper, value of A allows no spring lose efficacy.Here we consider A as the general coordinate of the mechanism. Thus the virtual angular displacement of joint A is(1)(r1+ r2) e 0,Td= dU?dA=0,dTd?dA=d2U?d2A 0.(13a)A= arcsiner1 r2,(13b)A= arcsiner1+ r2.Td /Ua bcTmaxTminUmaxUmin2Td-AU-AUmin1Stable positionUnstable positionA0Stable positionFigure2 Torque/energy versus position anglesPage 5 of 16Liand Hao Chin. J. Mech. Eng. (2019) 32:54 Equation (7a) can lead to the following expressionEquation (14) indicates that when the mechanism locates at the two limiting positions represented by Equa-tions (13a) and (13b), the following expression is truewhich indicates that the ratio between the output velocity and the input velocity is zero and is called the kinematic limb-singularity 24.Figure3 shows the motion of the mechanism which works around the right limiting position which is also one of the two kinematic limb-singularity positions. The mechanism moves from the initial non-singular position with no deflected springs (Figure3(a), passes the kin-ematic limb-singularity position (Figure3(b) and then arrives at the end non-singular position (Figure 3(c). During the motion as Figure 3 shows, the potential energy of the spring placed at joint C increases from zero to the maximum and then falls to zero. Thus if the stiffness of the torsional springs are not too large, the potential energy of the mechanism may have one local maximum and two local minimums, which correspond to the unstable position (b as shown in Figure3) and two stable positions (a and c as Figure3 shows). This kine-tostatic nonlinear stiffness characteristic is called the bi-stable characteristic.(14)dr3?dA= r1sinA b?a.(15)dr3?dA= 0If and only if the pin joints are attached springs, the mechanism does not exhibit the phenomenon that the potential energy increases firstly and then decreases, which means that there is no maximal potential energy during the motion because the pint joints rotate in one direction during the motion. Thus, the mechanism only produces the positive-stiffness characteristic but does not generate the bi-stable characteristic.According to Eqs. (10) and (11), the driving torque is to resist the all of the force/torque caused by all of the springs and the total potential energy of the mecha-nism is the sum of the potential energy of each spring. In other words, the mechanism may produce four types of kinetostatic nonlinear stiffness characteristics which are determined by the stiffness of springs placed at the joints.Four nonlinear stiffness characteristics including bi-stable characteristics, local negative-stiffness char-acteristic, local zero-stiffness characteristic and posi-tive-stiffness characteristic are shown in Figure4, which describes the driving torque varies with the input posi-tion angle, A. Unlike a generic elastic spring or structure, the driving force/torque applied on the mechanism with springs does not obey the Hookes law. If the mechanism is carried out the motion as Figure3(a)3(c) shows, it may produce four types of nonlinear stiffness character-istics depicted by Figure4(a)(d), which are addressed as follows: (1) Figure 4(a) describes the bi-stable characteristic which includes three domains, where domains i and iii are positive-stiffness and domain ii is nega-tive-stiffness. As Tdmax Tdmin 0. Thus we can conclude that the mechanism is located at the local minimal energy point when A = A1 and A = A3, respectively. According to Ref.28, the mechanism is in equilibrium when A = A1 and A = A3 corresponding to a and c as Figure2 shows, respectively.Differentiating Eq. (16) with respect to A yieldsC1= 4r31cosA0sin3A0 10er21cosA0sin2A0+ 8e2r1cosA0sinA0 r31cosA0sinA0 3r1r22cosA0sinA0 2e3cosA0+ 2er21cosA0+ 2er22cosA0,C2= a0?4r21sin3A0 6er1sin2A0+ 2e2sinA03r21sinA0 r22sinA0+ 4er1?,C3= 4r31sin4A0+ 10er21sin3A0 8e2r1sin2A0+ 5r31sin2A0+ 3r1r22sin2A0+ 2e3sinA0 8er21sinA0 er22sinA0+ 4e2r1 r31 3r1r22,C4= a0?4r21sin2A0cosA0 6er1sinA0cosA0+2e2cosA0 3r21cosA0 r22cosA0?.(19)r1cosA+ a r1cosA0 a0= 0,(20)r1sinA b/a = 0.(21)dTddA=d2Ud2A= KPC(r1sinA b/a)2+ KPC(r1cosA+ a r1cosA0 a0)?r1cosA?r21sinAcosA+ er1sinA?ab2?a3?.If the mechanism is located at A = A2, which is the solution of Eq. (20), thenCombing Eqs. (5a), (22b) and (22c) obtainsAccording to Eqs. (21), (22a) and (22d), the following equation can be obtainedEquation (17) can lead toThus we can conclude that the mechanism is in unsta-ble equilibrium when located at A = A2 corresponding to b as shown in Figure2.When the geometry parameters are given as r1 = 10 cm, r2 = 50 cm and e = 3 cm, and the initial input position angle is set to A0 = 5, the driving torque and potential energy variations versus the input position angle is shown in Figure5. In this paper, the unit of translational spring and the torsional spring is N/cm and Ncm/(), respectively. It should be pointed out that the initial input position angle should satisfy(22a)(r3 r30)|A=A2= (r1cosA+ a r1cosA0 a0)|A=A2 0,(22b)?r21sinAcosA+ er1sinA?A=A2 0,(22c)cosA|A=A2 0.(22d)?r1cosA?r21sinAcosA+ er1sinA?ab2?a3?A=A2 0.(23a)dTddA?A=A2=d2Ud2A?A=A2 0.Page 8 of 16Liand Hao Chin. J. Mech. Eng. (2019) 32:54 so as to allow the mechanism to pass the right kinematic limb-singularity position with starting from a non-singu-lar position.Figure 5 indicates that when KRA = KRB = KRC = 0 and KPC 0, the kinematic limb-singularity position is in the unstable equilibrium point. Moreover, it can be shown that the increment of the translational spring stiffness increases both of the values of driving torque in positive direction and in negative direction. The potential energy is also increased by the increment of the translational spring stiffness.4.1.2 Nonlinear Stiffness Characteristics When KRB = KRC = 0, KPC = 0, andKRA 0Substitution of the springs stiffness into Eq. (10) obtains the driving torque asarcsiner1 r2 A0 0.(26)U =12KRA(A A0)2.(27)Td= KRB?A arcsinr1sinA er2+A0+ arcsinr1sinA0 er2?1 r1cosA?a?.(28)U =12KRB?A arcsinr1sinA er2+A0+ arcsinr1sinA0 er2?2.KKKKKKb Potential energy versus input position angleInput position angle ()Position angle / Input position angle A ()a Driving torque versus input position angleDriving torque Td (Ncm)Potential energy U (Ncm)Figure5 Bi-stable characteristic when KRA = KRB = KRC = 0 and KPC 0Page 9 of 16Liand Hao Chin. J. Mech. Eng. (2019) 32:54 4.1.4 Nonlinear Stiffness Characteristics When KRA = KRB = 0, KPC = 0, andKRC 0The driving force can be simplified asConsidering to Eq. (6), the physical meaning of Eq. (29) is that the driving torque is to resist the torque due to the torsional spring added at the pin joint C.Substitution the springs stiffness into Eq. (11) obtains the potential energy as follows(29)Td= KRC?arcsinr1sinA er2arcsinr1sinA0 er2? r1cosA?a.(30)U =12KRC?arcsinr1sinA er2arcsinr1sinA er2?2.When r1 = 10cm, r2 = 50cm, e = 3cm, and A0 = 5, Figure8 depicts the driving torque and potential energy represented by Eqs. (29) and (30), respectively.Figure 8 shows that the mechanism produces the positive-stiffness characteristic when the pin joint C is attached a torsional spring exclusively.In addition, when KRA = KRB = KRC, Figures6 through 8 indicates that the stiffness of the driving torque curve caused by KRB is the greatest, the stiffness due to KRA is the second largest and the stiffness due to KRC is the lowest.4.2 Influences ofSpring Stiffness ontheNonlinear Stiffness CharacteristicsSection4.1 illustrates that KPC makes the mechanism to generate the bi-stable characteristic including the nega-tive domain and KRA, KRB or KRC only allow the mecha-nism to exhibit the positive-stiffness characteristic. The total torque can be obtained by linear superposition of the torque due to KRA, KRB, KRC and KPC. Therefore, an expected nonlinear stiffness characteristic may be con-structed by designing different values of KRA, KRB, KRC and KPC on the condition of KPC 0.When r1 = 10cm, r2 = 50cm, e = 3cm, A0 = 5, and KPC = 1N/cm, the nonlinear stiffness characteristics of the mechanism for different values of KRA, KRB and KRC is described by Figure9, where KRA = KRB = KRA,B.Figure9 indicates that one nonlinear characteristic can transformed to another one when the torsional springs stiffness, KRA, KRB and KRC, are set to different values when the translational spring, KPC, is nonzero. For a given translational spring stiffness, when the torsional spring stiffness is small, the mechanism exhibits the bi-stable characteristic. Increment of torsional springs stiffness delays the unstable equilibrium position and advances the second stable point. The bi-stable characteristic may degenerate to the local negative-stiffness characteristic and even the positive-stiffness characteristic with large increment of torsional springs stiffness.In addition, existence of local maximum potential energy point is the precondition of the bi-stable char-acteristic. When the torque curve has local negative-stiffness domain but no maximum potential energy point, the mechanism does not exhibit the snap-through phenomenon.When r1 = 10cm, r2 = 50cm, e = 3cm, A0 = 5 and KPC = 1N/cm, Figure10 depicts the nonlinear stiffness characteristic of the mechanism when one torsional spring stiffness is zero exclusively.Figure10 shows that when KPC is given as a constant, KRB has the greatest effect, KRA has the second greatest effect, and KRC has the smallest effect on the nonlinear stiffness characteristic of the mechanism, respectively.Figure6 Stiffness characteristics for different values of KRA when KRB = KRC = 0, and KPC = 0Page 10 of 16Liand Hao Chin. J. Mech. Eng. (2019) 32:54 5 Nonlinear Stiffness Characteristic withInitial LimbSingularity PositionSection4 shows that the mechanism may generate the positive-stiffness when torsional spring stiffness is great enough. Section5 manly discusses another approach for producing the positive-stiffness characteristic by making the mechanism to move from the right kinematic limb-singularity position (Figure3(b) to the nonsingular posi-tion (Figure3(c).The torque versus position angle of the mechanism starting from the right limiting kinematic-singularity position can be derived by substitutinginto Eq. (10), and is not detailed here.Within this situation, as the translational spring placed at prismatic joint C moves in one-direction, the potential energy increases with the increment of the input rota-tion angle, and does not exist the local minimum except the initial position. Thus the bi-stable characteristic does A0= arcsiner1+ r2not exist caused by KPC. For the three torsional springs attached at the three pin joints, the potential energy only increase. Therefore, the total potential energy increases during the motion of the mechanism, and the mechanism only exhibits the positive-stiffness characteristic.When r1 = 10cm, r2 = 50cm, e = 3cm, the torque curve versus the position angle is described by Figure11.Figure 11 verifies that the torque curve exhibits the positive-stiffness characteristic caused each spring. Thus the total torque caused by all of the springs does exhibit the positive-stiffness.6 Expected Nonlinear Stiffness Characteristic CreationAccording to Sections4 and 5, the mechanism only gener-ates the positive-stiffness characteristic when the mecha-nism moves from the kinematic limb-singularity position with