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最完整的英语词根词缀表(一)最完整的英语词根词缀表(一)Root, Prefix or Suffix Meaning Examples a, ac, ad, af, ag, al, an, ap, as, at to, toward, near, in addition to, by aside, accompany, adjust, aggression, allocate, annihilate, affix, associate, attend, adverb a-, an- not, without apolitical, atheist, anarchy, anonymous, apathy, aphasia, anemia ab, abs away from, off absolve, abrupt, absent -able, -ible Adjective: worth, ability solvable, incredible acer, acid, acri bitter, sour, sharp acerbic, acidity, acrid, acrimony act, ag do, act, drive active, react, agent, active, agitate acu sharp acute, acupuncture, accurate -acy, -cy Noun: state or quality privacy, nfancy, adequacy, intimacy, supremacy -ade act, product, sweet drink blockade, lemonade aer, aero air, atmosphere, aviation aerial, aerosol, aerodrome ag, agi, ig, act do, move, go agent, agenda, agitate, navigate, ambiguous, action -age Noun: activity, or result of action courage, suffrage, shrinkage, tonnage agri, agro pertaining to fields or soil agriculture, agroindustry -al Noun: action, result of action referral, disavowal, disposal, festival -al, -ial, -ical Adjective: quality, relation structural, territorial, categorical alb, albo white, without pigment albino, albite ali, allo, alter other alias, alibi, alien, alloy, alter, alter ego, altruism alt high, deep altimeter, altitude am, ami, amor love, like, liking amorous, amiable, amicable, enamoured ambi both ambidextrous ambul to walk ambulatory, amble, ambulance, somnambulist -an Noun: person artisan, guardian, historian, magician ana, ano up, back, again, anew anode, anagram, anagenetic -ance, -ence Noun: action, state, quality or process resistance, independence, extravagance, fraudulence -ancy, -ency Noun: state, quality or capacity vacancy, agency, truancy, latency andr, andro male, characteristics of men androcentric, android ang angular angle anim mind, life, spirit, anger animal, animate, animosity ann, annu, enni yearly annual, annual, annuity, anniversary, perrenial -ant, -ent Noun: an agent, something that performs the action disinfectant, dependent, fragrant -ant, -ent, -ient Adjective: kind of agent, indication important, dependent, convenient ante before anterior, anteroom, antebellum, antedate, antecedent antediluvian anthrop man anthropology, misanthrope, philanthropy anti, ant against, opposite antisocial, antiseptic, antithesis, antibody, antinomies, antifreeze, antipathy anti, antico old antique, antiquated, antiquity apo, ap, aph away from, detached, formed apology, apocalypse, aphagia aqu water aqueous -ar, -ary Adjective: resembling, related to spectacular, unitary arch chief, first, rule archangel, architect, archaic, monarchy, matriarchy, patriarchy, Archeozoic era -ard, -art Noun: characterized braggart, drunkard, wizard aster, astr star aster, asterisk, asteroid, astronomy, astronaut -ate Noun: state, office, fuction candidate, electorate, delegate -ate Verb: cause to be graduate, ameliorate, amputate, colligate -ate Adjective: kind of state inviolate -ation Noun: action, resulting state specialization, aggravation, alternation auc, aug, aut to originate, to increase augment , author, augment, auction aud, audi, aur, aus to hear, listen audience, audio, audible, auditorium, audiovisual, audition, auricular, ausculate aug, auc increase augur, augment, auction aut, auto self automobile, automatic, automotive, autograph, autonomous, autoimmune bar weight, pressure barometer be on, around, over, about, excessively, make, cause, name, affect berate, bedeck, bespeak, belittle, beleaguer belli war rebellion, belligerent, casus belli, bellicose bene good, well, gentle benefactor, beneficial, benevolent, benediction, beneficiary, benefit bi, bine two biped, bifurcate, biweekly, bivalve, biannual bibl, bibli, biblio book bibliophile, bibliography, Bible bio, bi life biography, biology, biometricsm biome, biosphere brev short abbreviate, brevity, brief cad, cap, cas, ceiv, cept, capt, cid, cip to take, to seize, to hold receive, deceive, capable, capacious, captive, accident, capture, occasion, concept, intercept, forceps, except, reciprocate cad, cas to fall cadaver, cadence, cascade -cade procession motorcade calor heat calorie, caloric, calorimeter capit, capt head decapitate, capital, captain, caption carn flesh carnivorous, incarnate, reincarnation, carnal cat, cata, cath down, with catalogue, category, catheter caus, caut burn, heat caustic, cauldron, cauterize cause, cuse, cus cause, motive because, excuse, accusation ceas, ced, cede, ceed, cess to go, to yield, move, go, surrender succeed, proceed, precede, recede, secession, exceed, succession cent hundred centennial, century, centipede centr, centri center eccentricity, centrifugal, concentric, eccentric chrom color chrome, chromosome, polychrome, chromatic chron time chronology, chronic, chronicle chronometer, anachronism, synchronize cide, cis, cise to kill, to cut, cut down fratricide, homicide, incision, incision, circumcision, scissors circum around circumnavigate, circumflex, circumstance, circumcision, circumference, circumorbital, circumlocution, circumvent, circumscribe, circulatory cit call, start incite, citation, cite civ citizen civic, civil, civilian, civilization clam, claim cry out exclamation, clamor, proclamation, reclamation, acclaim clin lean, bend decline, aclinic, inclination clud, clus claus to close, shut include, exclude, clause, claustrophobia, enclose, exclusive, reclusive, conclude co, cog, col, coll, con, com, cor with, together cohesiveness, cognate, collaborate, convene, commitment, compress, contemporary, converge, compact, confluence, convenient, concatenate, conjoin, combine, correct cogn, gnos to know recognize, cognizant, diagnose, agnostic, incognito, prognosis com, con fully complete, compel, conscious, condense, confess, confirm contr, contra, counter against, opposite contradict, counteract, contravene, contrary, counterspy, contrapuntal cord, cor, cardi heart cordial, concord, discord, courage, encourage corp body corporation, corporal punishment, corpse, corpulent, corpus luteum cort correct escort, cortage cosm universe, world cosmos, microcosm, cosmopolitan, cosmonaut cour, cur, curr, curs run, course occur, excursion, discourse, courier, course crat, cracy rule autocrat, aristocrat, theocracy, technocracy cre, cresc, cret, crease grow create, crescent, accretion, increase crea create creature, recreation, creation cred believe creed, credo, credence, credit, credulous, incredulous, incredible cresc, cret, crease, cru rise, grow crescendo, concrete, increase, decrease, accrue crit separate, choose critical, criterion, hypocrite cur, curs run current, concurrent, concur, incur, recur, occur, courier, precursor, cursive cura care curator, curative, manicure cycl, cyclo wheel, circle, circular Cyclops, unicycle, bicycle, cyclone, cyclic de- from, down, away, to do the opposite, reverse, against detach, deploy, derange, decrease, deodorize, devoid, deflate, degenerate dec, deca ten, ten times decimal, decade, decalogue, decimate, decathlon dec, dign suitable decent decorate dignity dei, div God divinity, divine, deity, divination, deify dem, demo people, populace, population democracy, demography, demagogue, epidemic dent, dont tooth dental, denture, orthodontist, periodontal derm skin, covering hypodermic, dermatology, epidermis, taxidermy di-, dy- two, twice, double divide, diverge, diglycerides dia through, across, between diameter, diagonal, dialogue dialect, dialectic, diagnosis, diachronic dic, dict, dit say, speak dictation, dictionary, dictate, dictator, Dictaphone, edict, predict, verdict, contradict, benediction dis, dif not, opposite of, reverse, separate, deprive of, away dismiss, differ, disallow, disperse, dissuade, divide, disconnect, disproportion, disrespect, distemper, disarray dit give credit, audit doc, doct teach, prove docile, doctor, doctrine, document, dogma, indoctrinate domin master, that which is under control dominate, dominion, predominant, domain don give donate, condone dorm sleep dormant, dormitory dox thought, opinion, praise orthodox, heterodox, paradox, doxology -drome run, step syndrome, aerodrome, velodrome duc, duct to lead, pull produce, abduct, product, transducer, viaduct, aqueduct, induct, deduct, reduce, induce dura hard, lasting durable, duration, endure dynam power dynamo, dynamic, dynamite, hydrodynamics dys- bad, abnormal, difficult, impaired, unfavorable dysfunctional, dyslexia, dyspathy
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Several item of the scenic area rule:In order to strengthen the safe management of whole city park, scenic area, Article 1 insures a public safety, according to relevant law, laws and regulation, combine my city physically, specially made settle this provision. The main representative director's safe work to this unit of the second park, scenic area takes a total responsibility, and be responsible for the implementation that the this unit safe management rule. The park, scenic area should build up various sound safe responsibility systems, by law establish a this unit safety management organization or provide with particularly part-time safe manager. Organization in the third park, scenic area management should according to rule capacity a reception a visitor, be visitor when the quantity exceed design capacity, the park management organization should adopt valid measure and avoid result in safety concealed suffer from. The fourth park, scenic area holds a large activity, have to report upper grade supervisor's section to agree, and want to be by rule to report a local public security official, fire fight section a reviewing an approval rear can carry on, protect unit to hold an activity in the cultural object should also report the city cultural object protection section a reviewing an approval.According to the principle of "who sponsor, who be responsible for", is undertaken an activity safety a work by the movable sponsor the first responsibility, and draw up a homologous safety a work a project and meet an emergency to prepare a case.Examine and approve the unit undertakes to take charge of a responsibility. The fifth park, scenic area wants perfect each item to meet an emergency to prepare a case, and periodically practice.In the gold week, main stanza day off and hold a large movable period, because immediately start to meet an emergency to prepare a case when the personnel is excessive or meet an urgent circumstance with abrupt affairs, and report toward the department concerned in time. The sixth park, scenic area wants to strengthen the safe technocracy work toward the special kind equipmentses, such as boiler and pressure container...etc. and build up sound safe management system of the special kind equipments and the technique file of the special kind equipments.Also to special kind equipments direct manage the section register register and carry on a periodical examination.Have never obtained the special kind equipments usage certificate and existence safety concealed suffer from of special kind equipments, can not throw in movement. The homework in the park, scenic area special kind personnel has to be investigate by nation or this city special kind homework's personnel's safe technique and hold a certificate a top Gang. The seventh pleasure boat, cable car, cableway in the park, scenic area, wharf etc. transportation tour and play facilities beard Be carried on quality and safety to examine by department concerned, and periodical maintenance check, keep intact, safety, valid.Each kind of transportation tour facilities and play facilities have to male show safe beard to know. The eighth park, scenic area are sight-see a black spot should the perfect safety guard against measure and establish obvious caution marking. The ninth road in the scenic area should meet provision standard, and press the road transportation a management of relevant rule that the constitution forbids a line, limit soon, caution etc. marking, guarantee road is unimpeded, traffic safety. The construction part should establish obvious construction marking, and provide safe protection measure. The tenth park, scenic area internal help be according to fire fight safe the provision be reasonable to establish fire fight headwaters and facilities device, promise fire fight passage to be unimpeded, and build up obligation fire brigade by law, organization correspond of fire drill.The fire fight facilities device should periodically check to maintain to maintain and keep intact. The 11th park, scenic area wants to strengthen the fire fight safety which constructs to thou inside the magistracy a management: (A)any thou construct of management, usage unit, have to strictly to the management of the whole fire sources, power supply and various easy Ran, explosive substance article. Forbid in the thou to construct the protection heap inside the scope to save an easy Ran combustible product of the firewood grass, timber...etc..Strictly forbid to lead the coal gas, liquefied petroleum gas...etc. into ancient building. (Two)forbid to make use of a thou to construct to be trip store, dining room, guest house or officers and workers' dormitory.The main palace house which forbids in the thou to construct carries on production and live to use fire. (Three)at point vital part place, should establish the obvious marking of "forbid firework".Appointed construct for the religious movable amenity thou, like important point light, burn paper, Fen joss-stick, have to be have the appointed location of fire fight facilities, equipments, and send specially assigned to put in the custody of or adopt on duty to patrol etc. measure. (Four)any constructs adjacent to other houses with thou, should have a fire prevention to box off a wall or develop fire fight passage.The thou constructs the passage, exit and entrance of sanctuary and have to keep unimpeded, can not stop and seize.(Five)When the thou constructs to need to be repair, should management construct by thou and usage unit and construction the unit together establish the fire fight safe measure, strict management system, explicit responsibility, and report superior after manage the section examination and approval then can start work.In the process of repair in, should have a fire prevention personnel's on duty to patrol a check, meet a circumstance to handle in time. The 12th park, scenic area should draw up homologous Lin2 Qu fire prevention management way.The point part should establish to obviously forbid smoke to forbid fire marking, and establish a specially assigned management. The 13th origin rules to city park bureau, Anne Jian bureau...etc. be responsible to organize the implement reaches agreement to release.中文:风景区的几项规定:第一条 为加强全市公园、风景区的安全管理,确保公众安全,根据有关法律、法规和规章,结合我市实际,特制定本规定。 第二条 公园、风景区的主要负责人对本单位的安全工作负总责,并负责本单位安全管理规定的落实。 公园、风景区应建立健全各项安全责任制,依法设立本单位安全管理机构或配备专兼职安全管理人员。 第三条 公园、风景区管理机构应当按照规定容量接待游人,当游人量超过设计容量时,公园管理机构应当采取有效措施,避免造成安全隐患。 第四条 公园、风景区举办大型活动,必须报上级主管部门同意,并要按规定报当地公安、消防部门审查批准后方可进行,在文物保护单位举办活动还应报市文物保护部门审查批准。按照“谁主办,谁负责”的原则,由活动主办单位承担活动安全工作第一责任,并制定相应的安全工作方案和应急预案。审批单位承担监管责任。 第五条 公园、风景区要完善各项应急预案,并定期演练。在黄金周、主要节假日及举办大型活动期间,因人员过多或遇有紧急情况和突发事件时,要立即启动应急预案,并及时向有关部门报告。 第六条 公园、风景区要加强对锅炉、压力容器等特种设备的安全技术管理工作,建立健全特种设备安全管理制度和特种设备技术档案。并向特种设备监督管理部门注册登记,进行定期检验。未取得特种设备使用证及存在安全隐患的特种设备,不得投入运行。 公园、风景区特种作业人员必须经国家或本市特种作业人员安全技术考核,持证上岗。 第七条 公园、风景区内的游船、缆车、索道、码头等交通游览及游乐设施须经有关部门进行质量和安全检验,并定期维护检查,保持完好、安全、有效。各类交通游览设施及游乐设施必须公示安全须知。 第八条 公园、风景区在游览危险地段应当完善安全防范措施、设置明显的警示标志。 第九条 风景区内的道路应当符合规定标准,并按道路交通管理的有关规定设置禁行、限速、警示等标志,保障道路畅通、交通安全。 施工部位应当设置明显的施工标志,并提供安全防护措施。 第十条 公园、风景区内应当按照消防安全规定合理设置消防水源和设施器材,保证消防通道畅通,并依法建立义务消防队,组织相应的消防演习。消防设施器材应当定期检查维修保养,保持完好。 第十一条 公园、风景区要加强对辖区内古建筑的消防安全管理: (一)凡古建筑的管理、使用单位,必须严格对一切火源、电源和各种易燃、易爆物品的管理。 禁止在古建筑保护范围内堆存柴草、木料等易燃可燃物品。严禁将煤气、液化石油气等引入古建筑物内。 (二)禁止利用古建筑当旅店、食堂、招待所或职工宿舍。禁止在古建筑的主要殿屋进行生产、生活用火。 (三)在重点要害场所,应设置“禁止烟火”的明显标志。指定为宗教活动场所的古建筑,如要点灯、烧纸、焚香时,必须在配有消防设施、设备的指定地点,并派专人看管或采取值班巡查等措施。 (四)凡与古建筑毗连的其他房屋,应有防火分隔墙或开辟消防通道。古建筑保护区的通道、出入口必须保持畅通,不得堵塞和侵占。(五)古建筑需要修缮时, 应由古建筑的管理与使用单位和施工单位共同制订消防安全措施,严格管理制度,明确责任,并报上级管理部门审批后,才能开工。在修缮过程中,应有防火人员值班巡逻检查,遇有情况及时处理。 第十二条 公园、风景区应当制定相应的林区防火管理办法。重点部位应当设置明显的禁烟禁火标志,并设专人管理。 第十三条 本规定由市园林局、安监局等负责组织实施和解释。
1024个西瓜
第一台镗床问世工场手工业虽然是相对落后的,但是它却训练和造就了许许多多的技工,他们尽管不是专门制造机器的行家里手,但他们却能制造各种各样的手工器具,例如刀、锯、针、钻、锥、磨以及轴类、套类、齿轮类、床架类等等,其实机器就是由这些零部件组装而成的。说起镗床,还先得说说达·芬奇。这位传奇式的人物,可能就是最早用于金属加工的镗床的设计者。他设计的镗床是以水力或脚踏板作为动力,镗削的工具紧贴着工件旋转,工件则固定在用起重机带动的移动台上。1540年,另一位画家画了一幅《火工术》的画,也有同样的镗床图,那时的镗床专门用来对中空铸件进行精加工。到了17世纪,由于军事上的需要,大炮制造业的发展十分迅速,如何制造出大炮的炮筒成了人们亟需解决的一大难题。世界上第一台真正的镗床是1775年由威尔金森发明的。其实,确切地说,威尔金森的镗床是一种能够精密地加工大炮的钻孔机,它是一种空心圆筒形镗杆,两端都安装在轴承上。1728年,威尔金森出生在美国,在他20岁时,迁到斯塔福德郡,建造了比尔斯顿的第一座炼铁炉。因此,人称威尔金森为“斯塔福德郡的铁匠大师”。1775年,47岁的威尔金森在他父亲的工厂里经过不断努力,终于制造出了这种能以罕见的精度钻大炮炮筒的新机器。有意思的是,1808年威尔金森去世以后,他就葬在自己设计的铸铁棺内。但是,威尔金森的这项发明没有申请专利保护,人们纷纷仿造它,安装它。1802年,瓦特也在书中谈到了威尔金森的这项发明,并在他的索霍铁工厂里进行仿制。以后,瓦特在制造蒸汽机的汽缸和活塞时,也应用了威尔金森这架神奇的机器。原来,对活塞来说,可以在外面一边量着尺寸,一边进行切削,但对汽缸就不那么简单了,非用镗床不可。当时,瓦特就是利用水轮使金属圆筒旋转,让中心固定的刀具向前推进,用以切削圆筒内部,结果,直径75英寸的汽缸,误差还不到一个硬币的厚度,这在当对是很先进的了。在以后的几十年间,人们对威尔金森的镗床作了许多改进。1885年,英国的赫顿制造了工作台升降式镗床,这已成为了现代镗床的雏型。车床诞生记早在古埃及时代,人们已经发明了将木材绕着它的中心轴旋转时用刀具进行车削的技术。起初,人们是用2根立木作为支架,架起要车削的木材,利用树枝的弹力把绳索卷到木材上,拉动绳子转动木材,用刀具车削。这种古老的方法逐渐演化,发展成了在滑轮上绕二三圈绳子,绳子架在弯成弓形的弹性杆上,来回推拉弓使加工物体旋转从而进行车削,这便是“弓车床”。到了中世纪,有人设计出了用脚踏板旋转曲轴并带动飞轮,再传动到主轴使其旋转的“脚踏车床”。16世纪中叶,法国有一个叫贝松的设计师设计了一种用螺丝杠使刀具滑动的车螺丝用的车床,可惜的是,这种车床并没有推广使用。时间到了18世纪,又有人设计了一种用脚踏板和连杆旋转曲轴,可以把转动动能贮存在飞轮上的车床上,并从直接旋转工件发展到了旋转床头箱,床头箱是一个用于夹持工件的卡盘。在发明车床的故事中,最引人注目的是一个名叫莫兹利的英国人,因为他于1797年发明了划时代的刀架车床,这种车床带有精密的导螺杆和可互换的齿轮。莫兹利生于1771年,18岁的时候,他是发明家布拉默的得力助手。据说,布拉默原先一直是干农活的,16岁那年因一次事故致使右踝伤残,才不得不改行从事机动性不强的木工活。他的第一项发明便是1778年的抽水马桶,莫兹利开始一直帮助布拉默设计水压机和其他机械,直到26岁才离开布拉默,因为布拉默粗暴地拒绝了莫利兹提出的把工资增加到每周30先令以上的请求。就在莫兹利离开布拉默的那一年,他制成了第一台螺纹车床,这是一台全金属的车床,能够沿着2根平行导轨移动的刀具座和尾座。导轨的导向面是三角形的,在主轴旋转时带动丝杠使刀具架横向移动。这是近代车床所具有的主要机构,用这种车床可以车制任意节距的精密金属螺丝。3年以后,莫兹利在他自己的车间里制造了一台更加完善的车床,上面的齿轮可以互相更换。不久,更大型的车床也问世了,为蒸汽机和其他机械的发明立下了汗马功劳。19世纪,由于高速工具钢的发明和电动机的应用,车床不断完善,终于达到了高速度和高精度的现代水平。刨床和铣床在发明过程中,许多事情往往是相辅相承、环环相扣的:为了制造蒸汽机,需要镗床相助;蒸汽机发明发后,从工艺要求上又开始呼唤龙门刨床了。可以说,正是蒸汽机的发明,导致了“工作母机”从镗床、车床向龙门刨床的设计发展。其实,刨床就是一种刨金属的“刨子”。由于蒸汽机阀座的平面加工需要,从19世纪初开始,很多技术人员开始了这方面的研究,其中有理查德·罗伯特、理查德·普拉特、詹姆斯·福克斯以及约瑟夫·克莱门特等,他们从1814年开始,在25年的时间内各自独立地制造出了龙门刨床。这种龙门刨床是把加工物件固定在往返平台上,刨刀切削加工物的一面。但是,这种刨床还没有送刀装置,正处在从“工具“向“机械”的转化过程之中。到了1839年,英国一个名叫博德默的人终于设计出了具有送刀装置的龙头刨床。另一位英国人内史密斯从1831年起的40年内发明制造了加工小平面的牛头刨床,它可以把加工物体固定在床身上,而刀具作往返运动。此后,由于工具的改进、电动机的出现,龙门刨床一方面朝高速切割、高精度方向发展,另一方面朝大型化方向发展。19世纪,英国人为了蒸汽机等工业革命的需要发明了镗床、刨床,而美国人为了生产大量的武器,则专心致志于铣床的发明。铣床是一种带有形状各异铣刀的机器,它可以切削出特殊形状的工件,如螺旋槽、齿轮形等。早在1664年,就有人依靠旋转圆形刀具制造出了一种用于切削的机器,这可算是原始的铣床了。当然,真正确立铣床在机器制造中地位的,要算美国人惠特尼了。1818年,惠特尼制造了世界上第一台普通铣床,但是,铣床的专利却是英国的博德默于1839年捷足先“得”的。1862年,美国的布朗制造出了世界上最早的万能铣床,这种铣床在备有万有分度盘和综合铣刀方面是划时代的创举。万能铣床的工作台能在水平方向旋转一定的角度,并带有立铣头等附件。同时,布朗还设计了一种经过研磨也不会变形的成形铣刀,接着还制造了磨铣刀的研磨机,使铣床达到了现在这样的水平。磨床和钻床磨削是人类自古以来就知道的一种古老技术,旧石器时代,磨制石器用的就是这种技术。以后,随着金属器具的使用,促进了研磨技术的发展。但是,设计出名副其实的磨削机械还是近代的事情,即使在19世纪初期,人们依然是通过旋转天然磨石,让它接触加工物体进行磨削加工的。1864年,美国制成了世界上第一台磨床,这是在车床的溜板刀架上装上砂轮,并且使它具有自动传送的一种装置。过了12年以后,美国的布朗发明了接近现代磨床的万能磨床。人造磨石的需求也随之兴起。如何研制出比天然磨石更耐磨的磨石呢?1892年,美国人艾奇逊试制成功了用焦炭和砂制成的碳化硅,这是一种现称为C磨料的人造磨石;2年以后,以氧化铝为主要成份的A磨料又试制成功,这样,磨床便得到了更广泛的应用。以后,由于轴承、导轨部分的进一步改进,磨床的精度越来越高,并且向专业化方向发展,出现了内圆磨床、平面磨床、滚磨床、齿轮磨床、万能磨床等等。与磨削技术相似,钻孔技术也有着久远的历史。考古学家现已发现,公元前4000年,人类就发明了打孔用的装置。古人在两根立柱上架个横梁,再从横梁上向下悬挂一个能够旋转的锥子,然后用弓弦缠绕带动锥子旋转,这样就能在木头石块上打孔了。不久,人们还设计出了称为“辘轳”的打孔用具,它也是利用有弹性的弓弦,使得锥子旋转。到了1850年前后,德国人马蒂格诺尼最早制成了用于金属打孔的麻花钻;1862年在英国伦敦召开的国际博览会上,英国人惠特沃斯展出了由动力驱动的铸铁柜架的钻床,这便成了近代钻床的雏形。以后,各种钻床接连出现,有摇臂钻床、备有自动进刀机构的钻床、能一次同时打多个孔的多轴钻床等。由于工具材料和钻头的改进,加上采用了电动机,大型的高性能的钻床终于制造出来了。不断发展的车床19世纪末到20世纪初,单一的车床已逐渐演化出了铣床、刨床、磨床、钻床等等,这些主要机床已经基本定型,这样就为20世纪前期的精密机床和生产机械化和半自动化创造了条件。在20世纪的前20年内,人们主要是围绕铣床、磨床和流水装配线展开的。由于汽车、飞机及其发动机生产的要求,在大批加工形状复杂、高精度及高光洁度的零件时,迫切需要精密的、自动的铣床和磨床。由于多螺旋线刀刃铣刀的问世,基本上解决了单刃铣刀所产生的振动和光洁度不高而使铣床得不到发展的困难,使铣床成为加工复杂零件的重要设备。被世人誉为“汽车之父”的福特,提出:汽车应该是“轻巧的、结实的、可靠的和便宜的”。为了实现这一目标,必须研制高效率的磨床,为此,美国人诺顿于1900年用金刚砂和刚玉石制成直径大而宽的砂轮,以及刚度大而牢固的重型磨床。磨床的发展,使机械制造技术进入了精密化的新阶段。在1920年以后的30年中,机械制造技术进入了半自动化时期,液压和电器元件在机床和其他机械上逐渐得到了应用。1938年,液压系统和电磁控制不但促进了新型铣床的发明,而且在龙门刨床等机床上也推广使用。30年代以后,行程开关——电磁阀系统几乎用到各种机床的自动控制上了。第二次世界大战以后,由于数控和群控机床和自动线的出现,机床的发展开始进入了自动化时期。数控机床是在电子计算机发明之后,运用数字控制原理,将加工程序、要求和更换刀具的操作数码和文字码作为信息进行存贮,并按其发出的指令控制机床,按既定的要求进行加工的新式机床。数控机床的方案,是美国的帕森斯在研制检查飞机螺旋桨叶剖面轮廓的板叶加工机时向美国空军提出的,在麻省理工学院的参加和协助下,终于在1949年取得了成功。1951年,他们正式制成了第一台电子管数控机床样机,成功地解决了多品种小批量的复杂零件加工的自动化问题。以后,一方面数控原理从铣床扩展到铣镗床、钻床和车床,另一方面,则从电子管向晶体管、集成电路方向过渡。1970年至1974年,由于小型计算机广泛应用于机床控制,出现了3次技术突破。第一次是直接数字控制器,使一台小型电子计算机同时控制多台机床,出现了“群控”;第二次是计算机辅助设计,用一支光笔进行设计和修改设计及计算程序;第三次是按加工的实际情况及意外变化反馈并自动改变加工用量和切削速度,出现了自适控制系统的机床。1968年,英国的毛林斯机械公司研制成了第一条数控机床组成的自动线,不久,美国通用电气公司提出了“工厂自动化的先决条件是零件加工过程的数控和生产过程的程控”,于是,到70年代中期,出现了自动化车间,自动化工厂也已开始建造。经过100多年的风风雨雨,机床的家族已日渐成熟,真正成了机械领域的“工作母机”。车床的发展史车床的发展大致可区分成四个阶段,雏型期,基本架构期、独立动力期与数值控制期,底下将针对 其 发展的过程加以介绍。车床的诞生不是发明出来的,而是逐渐演进而成,早在四千年前就记载有人利用简单的拉弓原理完成钻孔 的工作,这是有记录最早的工具机,即使到目前仍可发现 以人力做为驱动力的手工钻床,之后车床衍生而出,并被 用于木材的车削与钻孔,英文中车床的名称 Lathe(Lath 是 木板的意思 ) 就是由此而来,经过数百年的演进,车床的 进展很慢,木质的床身,速度慢且扭力低,除了用在木工 外,并不适合做金属切削,直到工业革命前。这段期间可 称为车床的雏型期18 世纪开始的工业革命,象征着以工匠主导的农业社会结束,取而代之的是强调大量生产的工业社会, 由于 各种金属制品被大量使用,为了满足金属另件的加工,车床成了关键性设备, 18 世纪初车床的床身已是 金属制,结构强度变大更适合做金属切削,但因结构简单, 只能做车削与螺旋方面的加工,到了 19 世纪才有完全以铁制 零件组合完成的车床,再加上诸如螺杆等传动机构的导入, 一部具有基本功能的车床总算开发出来。但因动力只能靠人 力、兽力或水力带动,仍无法满足需求,只能算是刚完成基 本架构的建构。瓦特发明了蒸气机,使得车床可藉由蒸气产生动力用来驱动车床运 转,此时 车床的动力是集中一处,再藉由皮带与齿轮的传递分散到工厂各处的车床, 20 世纪初拥有独立动力源的动力车床 (Engine Lathe) 终于被开发 ( 见图三 ) ,也将车床带到新的领域。此期间拜福特公司大量生产汽车所赐,许多汽车零件必须以车床加工,为了确保零件供应充足,供货商必须大量采购车床才能应付所需,即使到今天车床的发展仍受到汽车产业的荣枯所左右。20 世纪中,计算机被发明,不久计算机即被应用在工具机上,数值控制车床逐渐取代传统车床成为工厂 利器 ,生产效率倍增,零件加工精度更是大幅提升,且随着计算机软、硬件日趋进步与成熟,许多以往视为 无法加工的技术一一被克服, CNC 化工具机的比率成了国家现代化 的重要指标。从历史的角度来看促使车床发展除了 18 世纪工业革命与 20 世 纪汽车业兴起是主因外,另一项主因是切削刀具的进步,早期使用 的切削刀具材质是碳钢,切削速度只能限制在 20m/min 以下,而且 加工精度不佳,之后刀具材质采用合金钢,仍至今日的陶瓷刀具, 切削速度更提升到 1000m/min 以上,于是车床转速愈来愈高,进给 速度也愈来愈快,而且加工精度也从百年前的 1mm 大幅提0.001mm ,进步之快除了刀具的改良与技术的提升,当然有数值控制的配合也是最大的功臣。
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