核桃去殼機(jī)的設(shè)計(jì)
核桃去殼機(jī)的設(shè)計(jì),核桃,去殼,設(shè)計(jì)
附錄A
機(jī)械工程的發(fā)展歷程及展望
人類成為“現(xiàn)代人”的標(biāo)志就是制造工具。石器時(shí)代的各種石斧、石錘和木質(zhì)、皮質(zhì)的簡(jiǎn)單粗糙的工具是后來(lái)出現(xiàn)的機(jī)械的先驅(qū)。從制造簡(jiǎn)單工具演進(jìn)到制造由多個(gè)零件、部件組成的現(xiàn)代機(jī)械，經(jīng)歷了漫長(zhǎng)的過程。
??? 幾千年前，人類已創(chuàng)制了用于谷物脫殼和粉碎的臼和磨，用來(lái)提水的桔槔和轆轤，裝有輪子的車，航行于江河的船及槳、櫓、舵等。所用的動(dòng)力，從人自身的體力，發(fā)展到利用畜力、水力和風(fēng)力。所用材料從天然的石、木、土、皮革，發(fā)展到人造材料。最早的人造材料是陶瓷，制造陶瓷器皿的陶車，已是具有動(dòng)力、傳動(dòng)和工作三個(gè)部分的完整機(jī)械。
??? 人類從石器時(shí)代進(jìn)入青銅時(shí)代，再進(jìn)而到鐵器時(shí)代，用以吹旺爐火的鼓風(fēng)器的發(fā)展起了重要作用。有足夠強(qiáng)大的鼓風(fēng)器，才能使冶金爐獲得足夠高的爐溫，才能從礦石中煉得金屬。在中國(guó)，公元前1000～前900年就已有了冶鑄用的鼓風(fēng)器，并逐漸從人力鼓風(fēng)發(fā)展到畜力和水力鼓風(fēng)。
??? 15～16世紀(jì)以前，機(jī)械工程發(fā)展緩慢。但在以千年計(jì)的實(shí)踐中，在機(jī)械發(fā)展方面還是積累了相當(dāng)多的經(jīng)驗(yàn)和技術(shù)知識(shí)，成為后來(lái)機(jī)械工程發(fā)展的重要潛力。17世紀(jì)以后，資本主義在英、法和西歐諸國(guó)出現(xiàn)，商品生產(chǎn)開始成為社會(huì)的中心問題。
??? 18世紀(jì)后期，蒸汽機(jī)的應(yīng)用從采礦業(yè)推廣到紡織、面粉、冶金等行業(yè)。制作機(jī)械的主要材料逐漸從木材改用更為堅(jiān)韌，但難以用手工加工的金屬。機(jī)械制造工業(yè)開始形成，并在幾十年中成為一個(gè)重要產(chǎn)業(yè)。
??? 機(jī)械工程通過不斷擴(kuò)大的實(shí)踐，從分散性的、主要依賴匠師們個(gè)人才智和手藝的一種技藝，逐漸發(fā)展成為一門有理論指導(dǎo)的、系統(tǒng)的和獨(dú)立的工程技術(shù)。機(jī)械工程是促成18～19世紀(jì)的工業(yè)革命，以及資本主義機(jī)械大生產(chǎn)的主要技術(shù)因素。
??? 動(dòng)力是發(fā)展生產(chǎn)的重要因素。17世紀(jì)后期，隨著各種機(jī)械的改進(jìn)和發(fā)展，隨著煤和金屬礦石的需要量的逐年增加，人們感到依靠人力和畜力不能將生產(chǎn)提高到一個(gè)新的階段。
??? 在英國(guó)，紡織、磨粉等產(chǎn)業(yè)越來(lái)越多地將工場(chǎng)設(shè)在河邊，利用水輪來(lái)驅(qū)動(dòng)工作機(jī)械。但當(dāng)時(shí)的煤礦、錫礦、銅礦等礦井中的地下水，仍只能用大量畜力來(lái)提升和排除。在這樣的生產(chǎn)需要下，18世紀(jì)初出現(xiàn)了紐科門的大氣式蒸汽機(jī)，用以驅(qū)動(dòng)礦井排水泵。但是這種蒸汽機(jī)的燃料消耗率很高，基本上只應(yīng)用于煤礦。
??? 1765年，瓦特發(fā)明了有分開的冷凝器的蒸汽機(jī)，降低了燃料消耗率。1781年瓦特又創(chuàng)制出提供回轉(zhuǎn)動(dòng)力的蒸汽機(jī)，擴(kuò)大了蒸汽機(jī)的應(yīng)用范圍。蒸汽機(jī)的發(fā)明和發(fā)展，使礦業(yè)和工業(yè)生產(chǎn)、鐵路和航運(yùn)都得以機(jī)械動(dòng)力化。蒸汽機(jī)幾乎是19世紀(jì)唯一的動(dòng)力源，但蒸汽機(jī)及其鍋爐、凝汽器、冷卻水系統(tǒng)等體積龐大、笨重，應(yīng)用很不方便。
??? 19世紀(jì)末，電力供應(yīng)系統(tǒng)和電動(dòng)機(jī)開始發(fā)展和推廣。20世紀(jì)初，電動(dòng)機(jī)已在工業(yè)生產(chǎn)中取代了蒸汽機(jī)，成為驅(qū)動(dòng)各種工作機(jī)械的基本動(dòng)力。生產(chǎn)的機(jī)械化已離不開電氣化，而電氣化則通過機(jī)械化才對(duì)生產(chǎn)發(fā)揮作用。
??? 發(fā)電站初期應(yīng)用蒸汽機(jī)為原動(dòng)力。20世紀(jì)初期，出現(xiàn)了高效率、高轉(zhuǎn)速、大功率的汽輪機(jī)，也出現(xiàn)了適應(yīng)各種水利資源的水輪機(jī)，促進(jìn)了電力供應(yīng)系統(tǒng)的蓬勃發(fā)展。
??? 19世紀(jì)后期發(fā)明的內(nèi)燃機(jī)經(jīng)過逐年改進(jìn)，成為輕而小、效率高、易于操縱、并可隨時(shí)啟動(dòng)的原動(dòng)機(jī)。它先被用以驅(qū)動(dòng)沒有電力供應(yīng)的陸上工作機(jī)械，以后又用于汽車、移動(dòng)機(jī)械和輪船，到20世紀(jì)中期開始用于鐵路機(jī)車。蒸汽機(jī)在汽輪機(jī)和內(nèi)燃機(jī)的排擠下，已不再是重要的動(dòng)力機(jī)械。內(nèi)燃機(jī)和以后發(fā)明的燃?xì)廨啓C(jī)、噴氣發(fā)動(dòng)機(jī)的發(fā)展，是飛機(jī)、航天器等成功發(fā)展的基礎(chǔ)技術(shù)因素之一。
??? 工業(yè)革命以前，機(jī)械大都是木結(jié)構(gòu)的，由木工用手工制成。金屬(主要是銅、鐵)僅用以制造儀器、鎖、鐘表、泵和木結(jié)構(gòu)機(jī)械上的小型零件。金屬加工主要靠機(jī)匠的精工細(xì)作，以達(dá)到需要的精度。蒸汽機(jī)動(dòng)力裝置的推廣，以及隨之出現(xiàn)的礦山、冶金、輪船、機(jī)車等大型機(jī)械的發(fā)展，需要成形加工和切削加工的金屬零件越來(lái)越多，越來(lái)越大，要求的精度也越來(lái)越高。應(yīng)用的金屬材料從銅、鐵發(fā)展到以鋼為主。
??? 機(jī)械加工包括鍛造、鍛壓、鈑金工、焊接、熱處理等技術(shù)及其裝備，以及切削加工技術(shù)和機(jī)床、刀具、量具等，得到迅速發(fā)展，保證了各產(chǎn)業(yè)發(fā)展生產(chǎn)所需的機(jī)械裝備的供應(yīng)。
??? 社會(huì)經(jīng)濟(jì)的發(fā)展，對(duì)機(jī)械產(chǎn)品的需求猛增。生產(chǎn)批量的增大和精密加工技術(shù)的進(jìn)展，促進(jìn)了大量生產(chǎn)方法的形成，如零件互換性生產(chǎn)、專業(yè)分工和協(xié)作、流水加工線和流水裝配線等。
??? 簡(jiǎn)單的互換性零件和專業(yè)分工協(xié)作生產(chǎn)，在古代就已出現(xiàn)。在機(jī)械工程中，互換性最早體現(xiàn)在莫茨利于1797年利用其創(chuàng)制的螺紋車床所生產(chǎn)的螺栓和螺帽。同時(shí)期，美國(guó)工程師惠特尼用互換性生產(chǎn)方法生產(chǎn)火槍，顯示了互換性的可行性和優(yōu)越性。這種生產(chǎn)方法在美國(guó)逐漸推廣，形成了所謂“美國(guó)生產(chǎn)方法”。
??? 20世紀(jì)初期，福特在汽車制造上又創(chuàng)造了流水裝配線。大量生產(chǎn)技術(shù)加上泰勒在19世紀(jì)末創(chuàng)立的科學(xué)管理方法，使汽車和其他大批量生產(chǎn)的機(jī)械產(chǎn)品的生產(chǎn)效率很快達(dá)到了過去無(wú)法想象的高度。
??? 20世紀(jì)中、后期，機(jī)械加工的主要特點(diǎn)是：不斷提高機(jī)床的加工速度和精度，減少對(duì)手工技藝的依賴；提高成形加工、切削加工和裝配的機(jī)械化和自動(dòng)化程度；利用數(shù)控機(jī)床、加工中心、成組技術(shù)等，發(fā)展柔性加工系統(tǒng)，使中小批量、多品種生產(chǎn)的生產(chǎn)效率提高到近于大量生產(chǎn)的水平；研究和改進(jìn)難加工的新型金屬和非金屬材料的成形和切削加工技術(shù)。
??? 18世紀(jì)以前，機(jī)械匠師全憑經(jīng)驗(yàn)、直覺和手藝進(jìn)行機(jī)械制作，與科學(xué)幾乎不發(fā)生聯(lián)系。到18～19世紀(jì)，在新興的資本主義經(jīng)濟(jì)的促進(jìn)下，掌握科學(xué)知識(shí)的人士開始注意生產(chǎn)，而直接進(jìn)行生產(chǎn)的匠師則開始學(xué)習(xí)科學(xué)文化知識(shí)，他們之間的交流和互相啟發(fā)取得很大的成果。在這個(gè)過程中，逐漸形成一整套圍繞機(jī)械工程的基礎(chǔ)理論。
??? 動(dòng)力機(jī)械最先與當(dāng)時(shí)的先進(jìn)科學(xué)相結(jié)合。蒸汽機(jī)的發(fā)明人薩弗里、瓦特，應(yīng)用了物理學(xué)家帕潘和布萊克的理論；在蒸汽機(jī)實(shí)踐的基礎(chǔ)上，物理學(xué)家卡諾、蘭金和開爾文建立起一門新的科學(xué)——熱力學(xué)。內(nèi)燃機(jī)的理論基礎(chǔ)是法國(guó)的羅沙在1862年創(chuàng)立的；1876年奧托應(yīng)用羅沙的理論，徹底改進(jìn)了他原來(lái)創(chuàng)造的粗陋笨重、噪聲大、熱效率低的內(nèi)燃機(jī)而奠定了內(nèi)燃機(jī)的地位。其他如汽輪機(jī)、燃?xì)廨啓C(jī)、水輪機(jī)等都在理論指導(dǎo)下得到發(fā)展，而理論也在實(shí)踐中得到改進(jìn)和提高。
??? 早在公元前，中國(guó)已在指南車上應(yīng)用復(fù)雜的齒輪系統(tǒng)，在被中香爐中應(yīng)用了能永保水平位置的十字轉(zhuǎn)架等機(jī)件。古希臘已有圓柱齒輪、圓錐齒輪和蝸桿傳動(dòng)的記載。但是，關(guān)于齒輪傳動(dòng)瞬時(shí)速比與齒形的關(guān)系和齒形曲線的選擇，直到17世紀(jì)之后方有理論闡述。
??? 手搖把和踏板機(jī)構(gòu)是曲柄連桿機(jī)構(gòu)的先驅(qū)，在各文明古國(guó)都有悠久歷史，但是曲柄連桿機(jī)構(gòu)的形式、運(yùn)動(dòng)和動(dòng)力的確切分析和綜合，則是近代機(jī)構(gòu)學(xué)的成就。機(jī)構(gòu)學(xué)作為一個(gè)專門學(xué)科，遲至19世紀(jì)初才首次列入高等工程學(xué)院(巴黎的工藝學(xué)院)的課程。通過理論研究，人們方能精確地分析各種機(jī)構(gòu)，包括復(fù)雜的空間連桿機(jī)構(gòu)的運(yùn)動(dòng)，并進(jìn)而能按需要綜合出新的機(jī)構(gòu)。
??? 機(jī)械工程的工作對(duì)象是動(dòng)態(tài)的機(jī)械，它的工作情況會(huì)發(fā)生很大的變化。這種變化有時(shí)是隨機(jī)而不可預(yù)見；實(shí)際應(yīng)用的材料也不完全均勻，可能存有各種缺陷；加工精度有一定的偏差，等等。
??? 與以靜態(tài)結(jié)構(gòu)為工作對(duì)象的土木工程相比，機(jī)械工程中各種問題更難以用理論精確解決。因此，早期的機(jī)械工程只運(yùn)用簡(jiǎn)單的理論概念，結(jié)合實(shí)踐經(jīng)驗(yàn)進(jìn)行工作。設(shè)計(jì)計(jì)算多依靠經(jīng)驗(yàn)公式；為保證安全，都偏于保守，結(jié)果制成的機(jī)械笨重而龐大，成本高，生產(chǎn)率低，能量消耗很大。
??? 從18世紀(jì)起，新理論的不斷誕生，以及數(shù)學(xué)方法的發(fā)展，使設(shè)計(jì)計(jì)算的精確度不斷的提高。進(jìn)入20世紀(jì)，出現(xiàn)各種實(shí)驗(yàn)應(yīng)力分析方法，人們已能用實(shí)驗(yàn)方法測(cè)出模型和實(shí)物上各部位的應(yīng)力。
??? 20世紀(jì)后半葉，有限元法和電子計(jì)算機(jī)的廣泛應(yīng)用，使得對(duì)復(fù)雜的機(jī)械及其零件、構(gòu)件進(jìn)行力、力矩、應(yīng)力等的分析和計(jì)算成為可能。對(duì)于掌握有充分的實(shí)踐或?qū)嶒?yàn)資料的機(jī)械或其元件，已經(jīng)可以運(yùn)用統(tǒng)計(jì)技術(shù)，按照要求的可靠度，科學(xué)地進(jìn)行機(jī)械設(shè)計(jì)。
機(jī)械工程以增加生產(chǎn)、提高勞動(dòng)生產(chǎn)率、提高生產(chǎn)的經(jīng)濟(jì)性為目標(biāo)來(lái)研制和發(fā)展新的機(jī)械產(chǎn)品。在未來(lái)的時(shí)代，新產(chǎn)品的研制將以降低資源消耗，發(fā)展?jié)崈舻脑偕茉?，治理、減輕以至消除環(huán)境污染作為超經(jīng)濟(jì)的目標(biāo)任務(wù)。
??? 機(jī)械可以完成人用雙手和雙目，以及雙足、雙耳直接完成和不能直接完成的工作，而且完成得更快、更好。現(xiàn)代機(jī)械工程創(chuàng)造出越來(lái)越精巧和越來(lái)越復(fù)雜的機(jī)械和機(jī)械裝置，使過去的許多幻想成為現(xiàn)實(shí)。
??? 人類現(xiàn)在已能上游天空和宇宙，下潛大洋深層，遠(yuǎn)窺百億光年，近察細(xì)胞和分子。新興的電子計(jì)算機(jī)硬、軟件科學(xué)使人類開始有了加強(qiáng)，并部分代替人腦的科技手段，這就是人工智能。這一新的發(fā)展已經(jīng)顯示出巨大的影響，而在未來(lái)年代它還將不斷地創(chuàng)造出人們無(wú)法想象的奇跡。
??? 人類智慧的增長(zhǎng)并不減少雙手的作用，相反地卻要求手作更多、更精巧、更復(fù)雜的工作，從而更促進(jìn)手的功能。手的實(shí)踐反過來(lái)又促進(jìn)人腦的智慧。在人類的整個(gè)進(jìn)化過程中，以及在每個(gè)人的成長(zhǎng)過程中，腦與手是互相促進(jìn)和平行進(jìn)化的。
??? 人工智能與機(jī)械工程之間的關(guān)系近似于腦與手之間的關(guān)系，其區(qū)別僅在于人工智能的硬件還需要利用機(jī)械制造出來(lái)。過去，各種機(jī)械離不開人的操作和控制，其反應(yīng)速度和操作精度受到進(jìn)化很慢的人腦和神經(jīng)系統(tǒng)的限制，人工智能將會(huì)消除了這個(gè)限制。計(jì)算機(jī)科學(xué)與機(jī)械工程之間的互相促進(jìn)，平行前進(jìn)，將使機(jī)械工程在更高的層次上開始新的一輪大發(fā)展。
??? 19世紀(jì)時(shí)，機(jī)械工程的知識(shí)總量還很有限，在歐洲的大學(xué)院校中它一般還與土木工程綜合為一個(gè)學(xué)科，被稱為民用工程，19世紀(jì)下半葉才逐漸成為一個(gè)獨(dú)立學(xué)科。進(jìn)入20世紀(jì)，隨著機(jī)械工程技術(shù)的發(fā)展和知識(shí)總量的增長(zhǎng)，機(jī)械工程開始分解，陸續(xù)出現(xiàn)了專業(yè)化的分支學(xué)科。這種分解的趨勢(shì)在20世紀(jì)中期，即在第二次世界大戰(zhàn)結(jié)束的前后期間達(dá)到了最高峰。
??? 由于機(jī)械工程的知識(shí)總量已擴(kuò)大到遠(yuǎn)非個(gè)人所能全部掌握，一定的專業(yè)化是必不可少的。但是過度的專業(yè)化造成知識(shí)過分分割，視野狹窄，不能統(tǒng)觀和統(tǒng)籌稍大規(guī)模的工程的全貌和全局，并且縮小技術(shù)交流的范圍，阻礙新技術(shù)的出現(xiàn)和技術(shù)整體的進(jìn)步，對(duì)外界條件變化的適應(yīng)能力很差。封閉性專業(yè)的專家們掌握的知識(shí)過狹，考慮問題過專，在協(xié)同工作時(shí)配合協(xié)調(diào)困難，也不利于繼續(xù)自學(xué)提高。因此自20世紀(jì)中、后期開始，又出現(xiàn)了綜合的趨勢(shì)。人們更多地注意了基礎(chǔ)理論，拓寬專業(yè)領(lǐng)域，合并分化過細(xì)的專業(yè)。
??? 綜合-專業(yè)分化-再綜合的反復(fù)循環(huán)，是知識(shí)發(fā)展的合理的和必經(jīng)的過程。不同專業(yè)的專家們各具有精湛的專業(yè)知識(shí)，又具有足夠的綜合知識(shí)來(lái)認(rèn)識(shí)、理解其他學(xué)科的問題和工程整體的面貌，才能形成互相協(xié)同工作的有力集體。
綜合與專業(yè)是多層次的。在機(jī)械工程內(nèi)部有綜合與專業(yè)的矛盾；在全面的工程技術(shù)中也同樣有綜合和專業(yè)問題。在人類的全部知識(shí)中，包括社會(huì)科學(xué)、自然科學(xué)和工程技術(shù)，也有處于更高一層、更宏觀的綜合與專業(yè)問題。
附錄B
Mechanical engineering course of the development and prospects
Human become "modern" sign is to create tools. The Stone Age stone axes,stone hammers and wood, a simple cortex rough tool is the subsequent emergence of mechanical pioneer. From the manufacture of simple tools created by the evolution of a number of parts, components consisting of modern machinery, has undergone a long process.
Thousands of years ago, mankind has created for the cereals shelling and grinding of the acetabulum and grinding, to provide water and jigging machine Well Water Fetching Tool. equipped with wheels of a car, navigation on the river and paddle boats, organized, such as the rudder. Used the momentum from the man's own physical development of the use of animal power, hydro and wind. From the use of natural materials of stone, wood, soil, leather, the development of man-made materials. The earliest man-made materials are ceramics, pottery manufacture of pottery car, is motivation. Transmission and the integrity of the three parts of machinery.
Mankind from the Stone Age into the Bronze Age and further to the Iron Age. Winds Mong stoves for the blast, the development has played an important role. Powerful enough for the blast, metallurgical furnace can be sufficiently high temperature, can be extracted from ore in the metal. In China, 221 1000-900 years ago has had carriage for the blast. and gradually blast from human to animal and hydraulic blast.
15 ~ 16 centuries ago, the slow development of mechanical engineering. But in the Millennium of practice, the development of machinery or accumulated a lot of experience and technical knowledge, Later in mechanical engineering as an important potential for development. After the 17th century, capitalism in the United Kingdom, France, and the West European countries there, the volume of production has become the central issue.
The late 18th century, the steam engine from the application of the mining industry to promote textile, flour, and metallurgical industries. The main production machinery gradually materials from wood to switch to more resilient, it is difficult to manually processing metals. Machinery manufacturing industry began to take shape, and in several decades as an important industry.
Mechanical engineering through the growing practice, from the scattered, lovingly mainly rely on human ingenuity and craft a song, and gradually developed into a theoretical guidance. system and independent engineering. Mechanical engineering contributed 18 ~ 19th century industrial revolution and the capitalist machinery, large-scale production of the main technical factors.
Dynamics of the development of the important factors of production. The late 17th century, with all the mechanical improvements and development, as the coal and metal ore requirements of the yearly increase, People are relying on the human and animal production can be raised to a new stage.
In Britain, textile mills and other industries will be more and more factories set up by the river, and the use of turbine driven mechanical work. But, at that time, coal, tin and copper mines such as the groundwater, only with a large number of animal resources to upgrade and exclusion. In this production needs, the early 18th century there Newcomen the atmospheric steam engine to drive mine drainage pump. However, the steam engine of this high rate of fuel consumption, basically applies only to coal.
1765, Watt invented the separate condenser of the steam engine, reducing fuel consumption rates. 1781 watts is to create a provider rotary engine of the steam engine, the steam engine to expand the scope of its application. The invention of the steam engine and development, mining and industrial production, railways and shipping have all been of mechanical power. The steam engine to the 19th century is almost the only source of power, but the steam engine and boiler, condenser, cooling water system bulky, bulky and inconvenient to use.
End of the 19th century, the power supply system and electrical began the development and promotion. The early 20th century, the motor industry has replaced the production of the steam engine, all driven into the basic mechanical work force. Mechanized production is inseparable from the electrification and electrification through mechanization only play a role in the production.
Power stations initial impetus for the invention of the steam engine. Early 20th century, emerged as a highly efficient, high speed, high power of the turbine, there to keep the turbine water resources, and promote the power supply system to flourish.
The late 19th century after the invention of the internal combustion engine has improved and become light, small, high efficiency, easy manipulation, could start at any time the original motivation. It was first used to drive without an electricity supply mechanical work on land and later used in vehicles, mobile machinery and ships. to the mid-20th century for railway locomotives. Turbine and the steam engine in the engine exclusion, it has ceased to be an important force driving the machinery. After the invention of the internal combustion engine and gas turbines, jet engines and the development of the aircraft, Spacecraft such as the successful development of the basic technology one of the factors.
Before the industrial revolution, machinery mostly wooden structure, made of wood by hand. Metals (mainly copper, iron) just to manufacture equipment, locks, clocks, pumps and wood structure of small mechanical parts. Metal processing machine Carpenter mainly rely on the intricate communications to the needs of accuracy. The steam engine to power devices in promotion, and the concomitant emergence of mining, metallurgical, ships, locomotives and other large machinery, Forming and processing needs machining metal parts to more, the accuracy requirements are increasingly high. Application of metal materials from copper and iron to the development of the steel-based.
Forging including machining, forging, sheet metal process, welding, heat treatment technology and equipment, and machining technology and machine tools, knife, measuring tools, rapid development, and guarantee the development of the industrial production of machinery and equipment supply.
Socio-economic development of the machinery of the surge in demand for products. Mass production and the increasing precision processing technology progress, a great deal to promote the formation of production methods, such as the production of parts interchangeability, professional division of labor and cooperation, water lines and water processing, and other assembly line.
Simple parts interchangeability and professional collaboration division of production, in ancient times there was already. In mechanical engineering, Interchangeability Mocili reflected in the earliest in 1797 to use its originator of the thread lathe production of bolts and nuts. The same period, the United States engineers Whitney interchangeability with production rifle production methods, shows that the interchangeability of the feasibility and advantages. Such production methods in the United States gradually extended, forming a so-called "American production methods."
Early 20th century, Ford, the car manufacturer has created a pipeline assembly line. Mass production technology combined with Taylor in the late 19th century created the scientific management methods, vehicles and other large-scale production of machinery products will soon achieve production efficiency in the past unimaginable height.
20th century, the late machining the main features are : machine continuously improve the processing speed and accuracy, reduce dependence on manual skills; improve forming, machining and assembly of mechanization and automation; use NC machine tools, machining centers, group technology, the development of flexible manufacturing systems, allowing small and medium-sized manufacturers - multiple types of production to more efficient production of near-mass production level; Study hard and improve processing of a new type of metal and non-metallic materials forming and machining technology.
18 centuries ago, it all depends on the mechanical lovingly experience, intuition and craft mechanical production, with almost no scientific link. To the 18-19th century, the emerging capitalist economy under the promotion, access to scientific knowledge to start production, and the direct production of the Paradise, he started to learn scientific and cultural knowledge, The exchanges between them and the cross-fertilization achieved great results. In this process, and gradually form a set of mechanical engineering on the basis of the theory. .
Dynamic mechanical first and then combining advanced science. The invention of the steam engine were Safuli, Watt, applied physicist Papan and Blake's theory; In the steam engine on the basis of practice, physicist Kano, Portland reserves Kelvin build a new science -- thermodynamics. ICE is the basis of the theory of France Rosa founded in 1862; 1876 Otto application Rosa theory, radically improved his original creation of the true heavy, noise, thermal efficiency and lower engine lay the status of the internal combustion engine. Other steam turbine, gas turbine, the turbine so under the guidance of the theory of the development, Theory and practice also be improved and increased.
As early as 221, China has guidelines on the application of the complex gear systems, Chinese incense burner in the application of the standard to the people of the location of such cross-mechanical switch. Ancient Greece has cylindrical gear and bevel gear and worm drive documented. However, in terms of instantaneous transmission gear ratio and the relationship between tooth and tooth curve of choice, It was not until the 17th century after the side theory expounded.
Knob agencies and pedal crank linkage is the pioneer in the ancient civilization has a long history, But crank linkage in the form of kinetic and dynamic analysis of the precise and comprehensive, is the modern institutions of learning achievements. Mechanism as a specialized disciplines, until the early 19th century was the first to include the Higher Institute (Paris Institute of Technology) courses. Through theoretical study, people can accurately analyze various agencies, including the complex spatial linkages campaign and thus by the need to come up with new institutions.
Mechanical engineering work objects is a dynamic mechanical, its work will change very much. This change is sometimes random and unpredictable; Practical application of the material is not entirely uniform, there may be some shortcomings; Machining accuracy of this deviation, and so on.
And the static structure of the civil engineering work objects, the mechanical engineering problems more difficult to solve theoretical precision. Therefore, the early mechanical engineering only use simple theoretical concepts, practical experience work. Design calculations rely on the empirical formula; To ensure safety, conservative bias, the results were the heavy machinery and large, high cost, low productivity, energy consumption great.
From the 18th century onwards, new birth of the theory of continuous and mathematical methods, the development of the design and calculation precision continuously. The beginning of the 20th century, the emergence of various experimental stress analysis, People can use experimental methods and measuring the physical model on the part of the stress.
20 half-century, the finite element method and the computer's extensive use made of complex machinery and spare parts, components for power, torque, stress analysis and calculation possible. For a full grasp of the practice of experimental data or the machinery or its components, we can use statistical techniques, In accordance with the requirements of the reliability and scientific mechanical design.
Mechanical engineering to increase production, improve labor productivity, raising productivity goals for economic development and to the development of new machinery products. In the next era, new product development will lower their consumption of resources, the development of clean renewable energy, governance, reduce and ultimately eliminate pollution as a super-economic targets and tasks.
Machinery can be completed using hands and eyes, and both feet, his ears and can be completed directly direct the work completed and completed faster, and better. Modern mechanical engineering to create increasingly sophisticated and increasingly complex machinery and mechanical devices, so many previous fantasy become a reality.
Now mankind has been able sky and the upper reaches of the universe, the deep ocean dive, gleaned 10 billion light years distant, nearly monitor cellular and molecular. Emerging electronic computer hardware, software, human sciences began to strengthen, and partially replace the human brain means of science and technology, This is the artificial intelligence. This new development has demonstrated great influence, and in the coming years it will continue to create unimaginable miracle.
Human wisdom is not to reduce the growth of the hands, but instead asked for more hands, more sophisticated and more complicated work, thereby facilitating hand function. Hand practice, in turn, promote the wisdom of the human brain. In the human evolutionary process as a whole, and in each of the process of growing up, brain and hands is a mutual and parallel evolution.
Artificial Intelligence and mechanical engineering akin to the relationship between brain and the relationship between the hands, The only difference lies only in artificial intelligence hardware also need to use the machinery manufactured. The past, various machinery is inseparable from the operation and control its reaction speed and precision operation by the very slow evolution of the human brain and nervous system constraints, Artificial intelligence will eliminate this restriction. Computer science and mechanical engineering among the promotion, parallel, will mechanical engineering at a higher level to start a new round of large-scale development.
19 century, the mechanical engineering knowledge volume is still very limited. European universities which it is also the general and civil engineering as a single subject, known as civil engineering, 19 the second half of the century before becoming an independent discipline. The beginning of the 20th century, along with mechanical engineering technology development and knowledge of the total growth, mechanical engineering begins to decompose, the emergence of specialized branches. This decomposition trend in the mid-20th century, that is before and after the end of the Second World War reached its peak.
As mechanical engineering knowledge has expanded to the total far from the best all in the hands of individuals, some of specialization is essential. However, the excessive specialization of knowledge too divided, and narrow vision, Marketing concept, and not just to co-ordinate large-scale projects for the whole picture and the whole, and to narrow the scope of exchanges of technology, hin
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