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1、<p><b>  原文</b></p><p>  Commonly used grinding machine</p><p>  As a kind of important ultra-precision processing method,the advantage of grinding is high machining accuracy, p

2、rocessing materials range, almost suitable for all kinds of materials processing, grinding can get very high precision and shape accuracy, even can reach the limit, the machining accuracy of grinding device is simple, do

3、es not need a lot of the complex mechanical and not demanding equipment precision conditions.</p><p>  As a super finishing one method, grinding machine is mainly used for the high precision grinding workpie

4、ce plane, the surface of cylindrical workpieces both inside and outside, tapered face inside, sphere, thread face and other type surface. Its main types have dise-type grinding machine, shaft type grinding machine, magn

5、etic grinding machine and all kinds of special grinding machine.</p><p>  Dise-type grinding machine points single plate and double-tray two to double-tray grinding machine used the most common. In double-tr

6、ay polishing machine, multiple workpiece and into the mill plate, located on the cage between inside, maintain frame and workpiece drives by eccentric or planet of plane parallel movement. The mill rotating, the parallel

7、 with the grinding plate can not turn, or with grinding plate under negative spin, and can move to pressure workpiece (pressure adjustable). In add</p><p>  Shaft type grinding machine from positive, negativ

8、e spin of spindle drive work-piece or inquiry with adjustable grinding ring or abrasive (great) rotation, the structure is simple, used for grinding inside and outside cylindrical planes.</p><p>  Magnetic g

9、rinding machine is by using magnetic force transmission to stainless steel mill for high frequency workpiece needle to rotary motion; But for precision workpiece in the hole and blind Angle, tiny crack rise obvious good

10、polishing grinding remove burr effect.</p><p>  Special grinding machine by grinding workpiece in accordance with the different, have central hole grinding machine, steel ball grinding machine and gear grind

11、ing machine, etc.</p><p>  In addition, still have a kind of adopting similar centerless grinding principle unconditional grinding machine, used for grinding cylindrical workpieces.</p><p>  Gri

12、nding is by abrasive abrasive effect on surface of workpiece, to trace processing. Grinding workpiece surface dimension accuracy, form and position precision, abrasive tools, such as life and milling efficiency depends l

13、argely on whether grinding movement. In order to make the surface of workpiece grinding uniform, from the perspectives of kinematics concludes the following plane grinding best kinematics condition: firstly, workpiece wi

14、th relative research of plane movement, should guarantee </p><p>  Grinding basic principle is to use embedded in coating or pressure with the abrasive particles on grind workpiece with and, through research

15、 in the relative movement under certain pressure for processing surface finish machining process.</p><p>  The cylindrical plane grinding process is to use free grits are two plane of cylinder scraping and e

16、xtrusion process of removing materials to reduce cylindrical height, improve planar degree and reduce the surface roughness purpose. These remove effects through the cylindrical grinding plate with the relative movement

17、in grits role down to perform. Abrasive is the main medium grinding process. The grinding process according to abrasive change can be divided into three stages.</p><p>  The first stage: the broken free abra

18、sive stage. At the beginning of precision lapping ,initial larger grits cutting, then first participate in a belt of edges and abrasive polyhedron, cutting ability. The role of the pressure, the grits size by crushing ma

19、ke more grits are competing in cutting, then on one hand consumption dimensions and cylinder of processes, this phase residual surfaces grinding efficiency is higher, size, cylindrical surface roughness consumed fast. Bu

20、t this stage time is ve</p><p>  Second stage: the grits particular and Mosaic stage. Due to the effects of stress fluctuation grinding plate and cylinder interaction constantly rolling mill grain, make the

21、coarse grinding grain gradually broken into fine grits and size to converge, then the highest grinding efficiency, time also the longest. With the continuously detailed, all kinds of abrasive is also relatively stable st

22、age elements, at this stage of the geometry precision ball improved and basically reaches corresponding re</p><p>  The third stage: grits passivation and grinds light phase. In this phase abrasive most refi

23、ned for o. apms m the following three fine grits, grits by the shape of the original sharp geometry without sharp edges into the sleek sphere, grinding speed greatly reduced. Passivation of grits only to micro powder cyl

24、indrical plane more trace grinding, polishing quantity Grinding quantity is about from 0.2 to 0.3 microns per hour .This stage cylindrical surface roughness further reduce and eventually r</p><p>  Generall

25、y speaking, there are four main grind track: (1) linear grinding trajectory. This method is applicable to the steps of long and narrow plane workpiece grinding can obtain higher geometry precision, but not easily get sma

26、ller surface roughness. (2) swing linear grinding trajectory. Can achieve good straightness. (3) spiral grinding trajectory. Mainly used for discs shape or cylindrical workpieces grinding, flat end can gain a high flatne

27、ss and smaller surface roughness. (4) "8" glyph grin</p><p>  In the production practice, grinding is a kind of common finishing craft, grinding method unceasing progress and renewal, to adapt to t

28、he different processing requirements of various literature material reports, there are many methods of grinding, polishing, abrasive flow injection of ultrasonic machining, electrochemical polishing, chemical polishing,

29、magnetic abrasive grinding, liquid abrasive grinding etc exterior smooth the whole processing technology. The most commonly used and application </p><p>  Magnetic abrasive law is through magnetic polarity w

30、ill magnetic abrasive surface processing, suction pressure in surface processing and between the poles for millimeter clearance, can be in magnetic abrasive machining gap arrange them along the field, forming elastic mag

31、netic brush and pressure on the surface of workpiece attached. Rotating magnetic field or rotating product, make magnetic brush and relative motion processing, thus pure polisher a surface. The characteristics of magneti

32、c grindi</p><p>  Grinding machine adopts stepless speed regulation control system, can be easily adjusted adheasine grind various parts of grinding speed. Using electricity - gas proportional valve close-lo

33、op feedback grinding machine pressure control, can independence regulation pressure device. Slow falling installed in the up-tray to prevent the crash of brittleness slice. Through a time relay and a grinding counter, ca

34、n press processing requirements accurately Settings and control of milling time and grindin</p><p>  Grinding machine variable speed control method, grinding has three stages, namely beginning, formal stage

35、and end stage, beginning abrasive acc rotation, the official stage abrasive constant speed rotating, end stage abrasive slow down, whose character is, rotating grinding beginning in grinding speed, artificially controlle

36、d by slow from zero to acceleration of fast speed increases, when the abrasive ascended to the formal grinding speed, acceleration the half of the changes occur a inflection </p><p>  Use the characteristic

37、of a solid abrasive abrasive, according to the relative movement between grinding workpiece track density distribution, a reasonable design abrasive abrasive density distribution on, in order to make abrasive that occur

38、in the grinding process does not affect the abrasive wear face type, thereby significantly improve the precision of the surface type precision.</p><p>  Future as people are becoming more demanding to improv

39、e product performance, grinding machining accuracy and processing with its high quality, which has attracted the attention of people. Therefore, ultra-precision will be more conspicuous in the future.</p><p&g

40、t;<b>  譯文</b></p><p><b>  常用研磨機(jī)</b></p><p>  研磨是超精密加工中一種重要加工方法,其優(yōu)點(diǎn)是加工精度高,加工材料范圍廣,幾乎適合于各種材料的加工,研磨加工可以得到很高的尺寸精度和形狀精度,甚至可以達(dá)到加工精度的極限,研磨裝置簡(jiǎn)單,不需要大量復(fù)雜的機(jī)械并且不苛求設(shè)備的精度條件。</p>

41、<p>  作為超精加工的一種方法,研磨機(jī)主要用于研磨工件中的高精度平面、內(nèi)外圓柱面、圓錐面、球面、螺紋面和其他型面。其主要類(lèi)型有圓盤(pán)式研磨機(jī)、轉(zhuǎn)軸式研磨機(jī)、磁力研磨機(jī)和各種專(zhuān)用研磨機(jī)。</p><p>  圓盤(pán)式研磨機(jī)分單盤(pán)和雙盤(pán)兩種,以雙盤(pán)研磨機(jī)應(yīng)用最為普通。在雙盤(pán)研磨機(jī)上,多個(gè)工件同時(shí)放入位于上、下研磨盤(pán)之間的保持架內(nèi),保持架和工件由偏心或行星機(jī)構(gòu)帶動(dòng)作平面平行運(yùn)動(dòng)。下研磨盤(pán)旋轉(zhuǎn),與之平行的上研

42、磨盤(pán)可以不轉(zhuǎn),或與下研磨盤(pán)反向旋轉(zhuǎn),并可上下移動(dòng)以壓緊工件(壓力可調(diào))。此外,上研磨盤(pán)還可隨搖臂繞立柱轉(zhuǎn)動(dòng)一角度,以便裝卸工件。雙盤(pán)研磨機(jī)主要用于加工兩平行面、一個(gè)平面(需增加壓緊工件的附件)、外圓柱面和球面(采用帶V形槽的研磨盤(pán))等。加工外圓柱面時(shí),因工件既要滑動(dòng)又要滾動(dòng),須合理選擇保持架孔槽型式和排列角度。單盤(pán)研磨機(jī)只有一個(gè)下研磨盤(pán),用于研磨工件的下平面,可使形狀和尺寸各異的工件同盤(pán)加工,研磨精度較高。有些研磨機(jī)還帶有能在研磨過(guò)程中

43、自動(dòng)校正研磨盤(pán)的機(jī)構(gòu)。</p><p>  轉(zhuǎn)軸式研磨機(jī)由正、反向旋轉(zhuǎn)的主軸帶動(dòng)工件或研具(可調(diào)式研磨環(huán)或研磨棒)旋轉(zhuǎn),結(jié)構(gòu)比較簡(jiǎn)單,用于研磨內(nèi)、外圓柱面。 </p><p>  磁力研磨機(jī)是通過(guò)采用磁場(chǎng)力量傳導(dǎo)至不銹鋼磨針使工件作高頻率旋轉(zhuǎn)運(yùn)動(dòng);可對(duì)精密工件內(nèi)孔、死角、細(xì)小夾縫起到明顯較好的拋光研磨去除毛刺的效果。 </p><p>  專(zhuān)用研磨機(jī)依被研磨工件的不

44、同,有中心孔研磨機(jī)、鋼球研磨機(jī)和齒輪研磨機(jī)等。 </p><p>  此外,還有一種采用類(lèi)似無(wú)心磨削原理的無(wú)心研磨機(jī),用于研磨圓柱形工件。</p><p>  研磨是磨具通過(guò)磨料作用于工件表面,進(jìn)行微量加工的過(guò)程 。研磨工件表面的尺寸精度、形位精度、研磨工具的壽命及研磨效率等,在很大程度上取決于研磨運(yùn)動(dòng)。為使工件表面研磨均勻,從運(yùn)動(dòng)學(xué)角度歸納出如下的平面研磨最佳運(yùn)動(dòng)學(xué)條件:(1)工件相對(duì)研

45、具作平面運(yùn)動(dòng),應(yīng)保證工件被研磨表面上各點(diǎn)相對(duì)研具均有相同或相近的研磨軌跡;(2)研磨運(yùn)動(dòng)是由工件與研具之間的相對(duì)運(yùn)動(dòng)實(shí)現(xiàn)的,工件表面上各點(diǎn)的研磨運(yùn)動(dòng)速度應(yīng)盡可能相同;(3)研磨運(yùn)動(dòng)方向應(yīng)不斷變化,研磨紋路交錯(cuò)多變,以利于工件加工表面粗糙度的降低,但應(yīng)盡量避免工件被研磨表面上各點(diǎn)相對(duì)研具的研磨軌跡曲率變化過(guò)大;(4)研具或拋光盤(pán)工作表面的形狀精度會(huì)反映到工件表面上,所以工件的運(yùn)動(dòng)軌跡應(yīng)遍及整個(gè)研具表面并且分布均勻,以利于研具的均勻磨損;(

46、5)工件相對(duì)研具在被研磨材料的去除方向上具有運(yùn)動(dòng)自由度,這樣可以避免因研磨機(jī)械的導(dǎo)向精度不高而引起誤差。</p><p>  研磨基本原理是利用涂敷或壓嵌在研具上的磨料顆粒,通過(guò)研具與工件在一定壓力下的相對(duì)運(yùn)動(dòng)對(duì)加工表面進(jìn)行的精整加工的過(guò)程。</p><p>  圓柱面的研磨加工過(guò)程就是利用游離磨粒對(duì)圓柱兩平面進(jìn)行刮削和擠壓去除材料的過(guò)程,達(dá)到減小圓柱高度,提高平面度和降低表面粗糙度的目的

47、。這些去除作用要通過(guò)柱面與研磨盤(pán)的相對(duì)運(yùn)動(dòng)在磨粒的作用下來(lái)完成。磨料是研磨加工的主要介質(zhì)。整個(gè)研磨過(guò)程根據(jù)磨料的變化可分為三個(gè)階段。</p><p>  第一階段:游離磨料的破碎階段。精研初期較大的磨粒首先參與切削,這時(shí)磨料多呈帶棱角的多面體,切削能力強(qiáng)。在壓力的作用下,尺寸大的磨粒被破碎使更多的磨粒得以參加切削,這時(shí)圓柱體一方面消耗尺寸及上工序的殘留表面,這個(gè)階段磨削效率較高,尺寸消耗快,圓柱表面粗糙。但該階段

48、時(shí)間很短。</p><p>  第二階段:磨粒細(xì)化和鑲嵌階段。由于壓力的作用上下研磨盤(pán)和圓柱體相互作用不斷地輾壓磨粒,使粗磨粒逐漸破碎為細(xì)磨粒且大小趨于一致,這時(shí)磨削效率達(dá)到最高,時(shí)間也最長(zhǎng)。隨著磨料的不斷細(xì)化,各種要素也處于相對(duì)穩(wěn)定階段,在這個(gè)階段鋼球的幾何精度得以改善并基本達(dá)到相應(yīng)的要求,表面質(zhì)量逐漸提高,粗糙度下降。這個(gè)階段是鋼球的穩(wěn)定加工階段。</p><p>  第三階段:磨粒鈍

49、化和研光階段。在這個(gè)階段磨料絕大部分細(xì)化為O.3µm以下的微細(xì)磨粒,磨粒的形狀也由原來(lái)銳利的幾何體變?yōu)闊o(wú)銳棱的圓滑球體,磨削速度大大降低。鈍化了的磨粒微粉對(duì)圓柱面只能進(jìn)行更微量的研磨,研磨量大約0.2~O.3/µm/h。此階段圓柱表面粗糙度值進(jìn)一步降低,最終達(dá)到標(biāo)準(zhǔn)要求。</p><p>  一般來(lái)講,研磨軌跡主要有4種:(1)直線(xiàn)研磨運(yùn)動(dòng)軌跡。此種方法適用于臺(tái)階的狹長(zhǎng)平面工件研磨,可獲得較高

50、的幾何精度,但不易獲得較小的表面粗糙度。(2)擺動(dòng)式直線(xiàn)研磨運(yùn)動(dòng)軌跡??梢垣@得較好的平直度。(3)螺旋形研磨運(yùn)動(dòng)軌跡。主要用于圓片形或圓柱形工件端平面研磨,能獲得較高的平面度和較小的表面粗糙度。(4)“8”字形研磨運(yùn)動(dòng)軌跡。適用于平板類(lèi)工件的修整和小平面工件的研磨,能使相互研磨的平面介質(zhì)均勻接觸,并且研具均勻地磨損。</p><p>  在生產(chǎn)實(shí)踐中,研磨是一種常用的精加工工藝,研磨的方法不斷進(jìn)步和更新,為適應(yīng)不

51、同的加工要求,各種文獻(xiàn)資料報(bào)道的研磨方法有多種,有超聲波拋光、磨料流噴射加工、電解研磨、化學(xué)拋光、磁性磨料研磨、液體磨料研磨等表面光整加工技術(shù)。 最常用的并且應(yīng)用最多的是機(jī)械研磨,其特點(diǎn)是可獲得較高的尺寸精度、形狀精度和較低的表面粗糙度,但要求操作者有很高的技術(shù)水平和經(jīng)驗(yàn),加工效率低,勞動(dòng)強(qiáng)度大,加工質(zhì)量不易控制,表面殘余應(yīng)力大,表面殘留磨粒還會(huì)影響表面質(zhì)量。</p><p>  磁性研磨法是通過(guò)磁場(chǎng)的磁極將磁性

52、磨料吸壓在加工件表面,加工件表面與磁極之間可以有數(shù)毫米的間隙,磁性磨料在加工間隙中沿磁力線(xiàn)整齊排列, 形成彈性磁刷,并壓附在工件表面!旋轉(zhuǎn)磁場(chǎng)或旋轉(zhuǎn)加工件,使磁刷與加工件產(chǎn)生相對(duì)運(yùn)動(dòng),從而精磨工件表面。磁研磨加工的特點(diǎn)是,不管加工件表面形狀如何,只要使磁極形狀與加工表面形狀大體吻合,就可精磨有曲面的工件表面,因而磁研磨法適用于通常研削和研磨加工難以勝任的復(fù)雜形狀零件表面的光滑加工。</p><p>  研磨機(jī)采用

53、無(wú)級(jí)調(diào)速系統(tǒng)控制,可輕易調(diào)整出適合研磨各種部件的研磨速bocuo度。采用電—?dú)獗壤y閉環(huán)反饋研磨機(jī)壓力控制,可獨(dú)立調(diào)控壓力裝置。上盤(pán)設(shè)置緩降功能,有效的防止薄脆工件的破碎。通過(guò)一個(gè)時(shí)間繼電器和一個(gè)研磨計(jì)數(shù)器,可按加工要求準(zhǔn)確設(shè)置和控制研磨時(shí)間和研磨圈數(shù)。工作時(shí)可調(diào)整壓力模式,達(dá)到研磨設(shè)定的時(shí)間或圈速時(shí)就會(huì)自動(dòng)停機(jī)報(bào)警提示,實(shí)現(xiàn)半自動(dòng)化操作。   </p><p>  研磨機(jī)變速控制方法,研磨加工有三個(gè)階段,即開(kāi)始

54、階段、正式階段和結(jié)束階段,開(kāi)始階段磨具升速旋轉(zhuǎn),正式階段磨具恒速旋轉(zhuǎn),結(jié)束階段磨具降速旋轉(zhuǎn),其特征在于,在研磨加工開(kāi)始階段,人為控制磨具轉(zhuǎn)速的加速度從零由慢到快地增大,當(dāng)磨具轉(zhuǎn)速升到正式研磨速度的一半時(shí),加速度的變化出現(xiàn)一個(gè)拐點(diǎn),控制磨具轉(zhuǎn)速的加速度由最大值由快到慢地減小,直到磨具轉(zhuǎn)速達(dá)到正式的研磨速度,磨具轉(zhuǎn)速的加速度降為零。   </p><p>  利用固著磨料研磨的這一特點(diǎn),根據(jù)工件磨具間的相對(duì)運(yùn)動(dòng)軌跡密

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