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滚齿机床身部件结构设计【13张CAD图纸+毕业答辩论文】

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滚齿机床身部件结构设计

摘要:齿轮加工机床是一种技术含量高且结构复杂的机床。滚齿机又是齿轮加工机床中应用最为广泛的一种,滚齿机主要是用于加工圆柱齿轮和蜗轮的。

滚齿机床身为箱形结构,与底座铸成一个整体,左上部是方形导轨,留安放工作台之用;右上部是用来固定刀架、立柱;床身内部安装差动机构;床身后端连出分齿挂轮架;背面为主传动牙箱;左面底盘为冷却箱;右面底盘为润滑油箱;主电动机和冷却电动机都安装在床身上,方形导轨中间装一丝杆供移动工作台之用,分度挂轮架处的手柄供铣正齿轮或者斜齿轮时操纵使用。

差动机构是用来加工斜齿轮的,分析了差动机构的组成原理,并进行了相应的设计计算,确定了其结构形状与参数。

这次设计是在传统的设计思路上对原有产品的改造,力求满足强度、刚度、经济性、工艺性等方面的要求。


关键词:滚齿机;床身装配结构;差动机构


Abstract: The gear finishing lathe is one kind of technical content high also the structure complex engine bed. The gear-hobbing machine also is a machine equipment which is applies the most widespread, the gear-hobbing machine mainly is uses in processing the cylindrical gears and the worm gear.

The body of gear-hobbing machine is box shape structure, casts a whole with the foundation upside, the left is the square shape of guide rail, remains places using of the work table; Right upside is uses for the immovable support of the column; The interior of the body installs the differential motion organization; Behind the body is main transmission gear-box; Back transmission is tooth box, in left side of it is a cooling tank; the right side of it is lubricating-oil tank; The main motor and the cooling electric motor all are installed on the lathe bed, among the square shape guide rail installs a lead screw to move the work table, divides the swing frame gear place handle for when milling spur gear or the helical gear operates the use.

The differential device is uses for to process the helical gear, analyzed the differential device composition principle, carried on the corresponding design calculation, and determined its structure shape and the parameter.

This design improves product transformation on the basic of traditional design, makes effort to satisfy the request as intensity, rigidity, efficiency, process.


Key words: Gear-hobbing machine; assembling structure of the body; Differential motion mechanism


目    录

1  前   言1

2  总体设计3

2.1滚齿机工作原理3

2.1.1加工直齿轮时机床的运动和传动原理3

2.1.2加工斜齿圆柱齿轮时的运动和传动原理3

2.2拟定选择传动方案4

2.3 主切削力的估算及电动机的选择8

3  机床床身装配结构设计9

3.1 滚齿机床身的特性9

3.2 滚齿机床身的结构分析9

3.3 床身材料的选择10

3.4 床身导轨及机床的润滑11

4  差动机构设计13

4.1 总传动比的计算13

4.2 传动比的分配13

4.3 设计计算14

4.3.1 螺旋伞齿轮的设计14

4.3.2 运动合成机构设计15

4.3.3差动蜗轮设计16

4.3.4圆柱直齿轮的设计20

5 结束语25

参考文献26

致    谢27

附件清单28


1 前   言

齿轮加工机床是一种技术含量高而且机构复杂的机床系统,由于齿轮使用的量大面广,齿轮加工机床已成为机械等行业的关键设备。特别是,随着汽车行业的高速发展,对齿轮的需求量日益增加,对齿轮加工的效率、质量及加工成本的要求愈来愈高,使齿轮加工机床在汽车、摩托车等行业中占有越来越重要的作用。滚齿机是齿轮加工机床中的一种,其占齿轮加工机床拥有量的40%~50%。它主要用来加工圆柱齿轮和蜗轮等。传统滚齿机在加工过程中有以下特点:

a.滚削钢齿轮时,应用切削液可提高刀具寿命,改善加工表面的质量和利于排出切削热而不致引起机床的热变形;

b.机床漏、混油严重;

c.加工成本高;

d.生产效率低下,加工质量差,难以满足现代企业生产的要求。

近几年,我国在滚齿机设计技术方面研究的主要内容经历了从传统机械式滚齿机通过数控改造发展为2-3轴(直线运动轴)实用型数控高效滚齿机,到全新的六轴四联动数控高速滚齿机的开发。滚齿机加工(钢件)全部采用湿式滚齿方式。目前,国内主要滚齿机制造商重庆机床厂及南京二机床有限责任公司生产的系列数控高效滚齿机已采取全密封护罩加油雾分离器和磁力排屑器的方式部分地解决环保问题。世界上滚齿机产量最大的制造商——重庆机床厂从2001 年开始研究面向绿色制造的高速干切滚齿技术,2002年初研制成功既能干切又能湿切的YKS3112六轴四联动数控高速滚齿机,2003年初又开始研制面向绿色制造的YE3116CNC7高速干式切削滚齿机,即将进入商品化阶段。


内容简介:
International Journal of Machine Tools & Manufacture 41 (2001) 915922A standard conical point drill grinding machineM.A. Fugelso*Industrial Engineering Department, The University of Minnesota, 176 Engineering Building, Duluth, MN 55812,USAReceived 13 August 1999; received in revised form 7 July 2000; accepted 13 July 2000AbstractThis paper describes a drill grinding machine that can produce conical twist drill points with very accu-rately specified point shapes. The machine is adjusted by precise orthogonal movements using shims andgages to make sure that the drill parameters are set precisely. The confidence in the point shape producedis high enough that inspection of the points produced is not necessary.Keywords: Drill grinding; Drill sharpening; Cone model drill point; Twist drill grinding1. IntroductionThere are some problems in the adjustment of existing simple conical twist drill grindingmachines. Many of these machines allow the operator to easily vary point parameters that arenot very important as far as drilling performance is concerned, such as point angle, and at thesame time do not allow straightforward adjustment of parameters that have a very powerful effecton performance, such as skew distance, d parameter described by Tsai and Wu 1,2 and wparameter described by Fugelso 3,4. Most machines adjust w in a trial-and-error manner untilan acceptable but uncharacterized drill is produced. This leads to variations in batches of drillpoints produced.After a conical drill point has been produced it is very difficult to measure the point andascertain its model parameters. It is easy to find the sum of q and f because twice that sum isthe easily measured point angle, but separating q and f is difficult. The measured chisel edgeangle contains the w parameter and w cannot easily be separated from the chisel edge angle.While the d parameter cannot be measured directly, Tsai and Wu 1 showed that it can be inferred* Fax: +1-218-726-8596.E-mail address: mfugelso (M.A. Fugelso).nts916 M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 915922Nomenclatured distance between tip of drill and tip of grinding cone measured parallel to coneaxisD drill diameterHRheight of calibrating rod tip over the baseHSheight of contact point of square calibrating bar and grinding wheel over the baseL a calibration distanceP skew distance adjusting shim thicknessP0thickness of shim P that causes the drill axis to intersect the cone axis AA9Q a parameter adjusting shim thicknessQ0shim thickness required to produce d=0 on a drill of diameter D=0QCthickness of shim Q in place during Q0calibration, any thickness will doR distance from base to top side of gage GR0distance from base to tip of calibrating rodS skew distance between drill axis and grinding cone axisw width of gage block to set w parameterw0width of gage block that lines up with cone axis in side view, Fig. 2W drill web thicknessq grinding cone half anglef angle between drill axis and grinding cone axisw rotation of drill blank about its own axis before grindingfrom the chisel edge angle if the other parameters are known. This confounding of cone modelparameters makes it difficult to inspect points, and it is therefore important to produce the pointscorrectly in the first place.This paper describes a twist drill grinding machine that allows the setting of all of the conedrill point parameters and makes sure that these parameters are well known and repeatable. Thisis because they are set directly from first principles using shims and gage blocks to position thedrill blank precisely. And it can be calibrated with as little knowledge of grinder part dimensionsas possible.2. Description of grinderFig. 1 shows the cone model of a twist drill point with the parameters cone half angle (q),drill axis to cone axis angle (f), skew distance (S) and distance from cone tip to drill tip (d)asdescribed by Tsai and Wu 1.Fig. 2 shows the configuration of the standard conical drill grinder. The axis AA9 is the axisof the cone model. The angle q is set at 30 as this gives a good distribution of relief angle alongthe cutting edge, but not too large a chisel edge angle, see Fugelso 4; a chisel edge angle lessthan 120 sacrifices potential drill performance. The angle f is fixed at 29 to give a standardnts917M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 915922Fig. 1. Cone model of a twist drill point.Fig. 2. Side view of the standard conical twist drill grinder.point angle of 118 , the point angle being double the sum of f and q. If desired q and f couldbe different, but the above values should be adequate for a wide range of applications.Skew distance has a great effect on drill geometry. A small change in skew distance changesthe relief angles as defined in 5 a great deal. An increase in skew distance results in a uniformnts918 M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 915922increase in relief angle over the entire length of the cutting edge of the drill. Typically the skewdistance is about equal to the web thickness. The skew distance S can be accurately adjusted byvarying the thickness of shim P, Fig. 3. The value of skew distance is equal to a machine constantP0determined after construction minus the shim thickness P.The d parameter can be adjusted with shim Q, Fig. 3. The shim Q causes displacements atright angles to the displacements caused by shim P, raising and lowering the drill blank. Theshim thickness Q is given by the following equation that is a function of drill diameter D andthe d parameter:Q5Q02D2 sin 45 sin(q+f)2dcos q. (1)The d parameter is a function of the drill diameter because the drill is held in a V groove. Ifthe drill were held in a chuck, d would not be a function of drill diameter. The value of d shouldbe equal to 6090% of the drill diameter, as small as possible without making the chisel edgeangle too large, i.e., greater than 133 . This results in the relief angle increasing as much aspossible along the cutting edge traveling toward the drill axis. Most existing drill grinders do notallow adjustment of this parameter and have a built-in fixed d value that is marginally acceptablefor large drills and much too large for smaller drills.The top side of gage G must be at a distance J from the cone tip to properly align w, Fig. 2.J is given by:J5d1d cos q2 sin(q+f). (2)Then distance R would be:R5R02J. (3)Fig. 3. Isometric view of the standard conical twist drill grinder.nts919M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 915922Fig. 4. Setting distance R, with drill rotated 90 about cone axis.Fig. 4 shows the distance R from gage G to the base. The gage G must be positioned along theZ axis of the flute stop, Fig. 5, so that it engages the flute of the drill, but this is not a precisionadjustment because of the concave shape of the flute. The w parameter is adjusted by the width(w) of gage G. The drill holder rotates 90 about the cone axis AA9. Then the gage contacts thepoint on the drill where the cutting edge will reach the outside diameter after grinding has takenplace, Figs. 4 and 5. This results in setting w from first principles, w is given by the following equ-ation:Fig. 5. Setting drill point w parameter.nts920 M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 915922w5w02W22D2tan w. (4)The w parameter ranges from zero to a small positive angle, not more than +15 . Increasing wby 1 increases the chisel edge angle by 1 . Increasing w has a beneficial effect on the distributionof relief angle along the cutting edge, see Fugelso 3,4. But doing this increases chisel edgeangle. The chisel edge angle must be less than about 133 or the chisel edge will be too long.Often the w parameter is increased to compensate for a built-in d parameter that is too large, asdemonstrated by Fugelso 3.After touching off the drill flute on the gage G as shown in Fig. 4, the drill is clamped in theV groove drill holder and the drill holder is rotated backward by 90 on the cone axis, encoun-tering the grinding wheel and forming half the point. The drill is then loosened and rotated about180 , and the drill holder is rotated forward 90 . The second flute is touched off on gage G toline up the second half of the point and the drill is reclamped. Then the drill holder is rotatedback again, forming the second half of the point. For clarity the clamps and AA9 axis rotationstops are not shown on the figures.3. CalibrationIt is desirable to calibrate the machine without explicitly knowing the dimensions of the grinderbecause then the calibration is not affected by inaccurately formed or measured parts. While thereis no easy way to get around measuring the angular dimensions, it is possible to calibrate withoutknowing many of the linear dimensions. But, finding P0is very simple and may be found utilizingordinary measuring tools.The calibration of Q0and R0assumes that the grinding wheel can be moved along its axis ofrotation and returned to a previous axial position accurately. R0may be found by replacing therotating part of the grinder with a conical pointed calibrating rod, dashed lines in Fig. 2. R0isthe distance from the base to the tip of the rod when the side of the cone touches the grindingwheel. The height HRfrom the tip of the rod to the base must be recorded to use in the calibrationof Q0. HRonly needs to measured once because it has a constant ratio with R0.Q0may be found by placing a square calibrating bar on the V groove and measuring theheight HSfrom the base to the point of contact of the square bar and the grinding wheel, dashedlines in Fig. 2. Also, the distance L should be measured at this point for future recalibrations. Then:Q05HR2HS1QC. (5)In a grinding machine intended to produce a wide range of drill diameters, the range of shimQ thicknesses required may be inconveniently large. The grinding wheel may be translated to theleft increasing L, Fig. 2. Increasing L from its originally measured value will increase d and threeof the calibration constants according to the following relations:Dd5DL/tan q2DL tan(902q2f) cos q, DR05DL/sin q, DHR5DL/tan q, DHS(6)nts921M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 9159225DL tan(902q2f).Eq. (6) also may be used to recalibrate the machine after dressing the side of the grindingwheel. The effect of wheel dressing is to create a small DL.4. AccuracyWhen the V groove drill holder is in the position shown in Fig. 2, there is a very small gapbetween the drill point and the grinding wheel. The gap width is given by:Gap width5S- (W/2)2D. (7)The gap width approaches 0.0 as the skew distance approaches its lower limit of W/2. This gapincreases with increasing skew distance. Neglecting this gap produces a small error in of thesecond term of Eq. (2) of about 1%. This could result in a fraction of a degree error in the wparameter. This is acceptable because w is normally specified in whole degrees, not fractions.5. DiscussionThe drill points created by this standard drill grinder can be compared with drills produced byother grinders in a number of ways. The surface of the drill flank and its edges could be measuredwith a coordinate-measuring machine (CMM) to compare the point produced by a productiongrinder with a standard point. This would tell if the two points were the same. However, it wouldbe good for the comparison if the drill parameters of the point could be extracted from the flanksurface points measured by the CMM. Then the production drill grinder could be adjusted in arational way so that it produces points the same as the standard drill grinder.Another comparison would be to conduct tool life tests of the standard point and the productionpoint, but the problem is that the cutting performance could be quite similar for points that haddifferent shapes. The drills produced by the standard grinder are intended to provide a geometricbenchmark for tests of new drill point shapes.A third comparison would be to check the relief angle of the two drill points at the outerdiameter (OD) and at a point near the end of the chisel edge. These angles are critical to drillperformance. The relief angle near the chisel edge should be larger than at the OD. This approachwould yield good drilling performance but still leave the shape of the production drill incom-pletely specified.6. ConclusionsWhile cam-driven mechanical grinding machines and computer-controlled grinders can producea wide variety of points with programmed changeover from one point shape to another, the drillnts922 M.A. Fugelso / International Journal of Machine Tools & Manufacture 41 (2001) 915922grinder proposed in this paper, although somewhat tedious to set up, can produce large batchesof identical cone points with high confidence in the point shape being produced. This is especiallyimportant for very small diameter drills because they are difficult to inspect. These drills can beused for benchmark tests of common conical drill point performance for comparison with morecomplex points produced for research. Future work would include designing measuring techniquesfor production drill flank shapes, with this grinder providing the first step toward rational compari-sons of drilling performance.References1 W.D. Tsai, S.M. Wu, Computer analysis of drill point geometry, International Journal of Machine Tool Designand Research 19 (2) (1979) 95108.2 W.D. Tsai, S.M. Wu, A mathematical model for drill point design and grinding, ASME Journal of Engineeringfor Industry 101 (1979) 330340.3 M.A. Fugelso, Cylindrical flank twist drill points, ASME Journal of Engineering for Industry 105 (1983) 183186.4 M.A. Fugelso, Conical flank twist drill points, International Journal of Machine Tools and Manufacture 30 (2)(1990) 291295.5 ISO 3002/I-1977(e): Geometry of the Active Part of Cutting Tools, Part 1: General Term, Reference Systems, Tooland Working Angles.nts 外文翻译 专 业 机械设计制造及其自动化 学 生 姓 名 黄 海 班 级 BD 机制 051 学 号 0520110112 指 导 教 师 邢 青 松 nts 1 外文资料名称: A standard conical point drill grinding machine 外文资料出处: International journal of machine tools&manufacture 附 件: 1.外文资料翻译译文 2.外文原文 指导教师评语: 签名: 年 月 日 (用外文写 ) nts 2 一个标准的圆锥点钻磨床 M.A. Fugelso 黄海 译 摘要 : 本文介绍了一种钻头磨床能产生锥形麻花钻点 并带有 非常准确 的 点的形状。 该机器 通过 精确正交动作用垫片 来 调整, 这样是为了 确保 钻削 参数设定准确。在这一点形状制作 上有足够的精度 , 以至于 要点制作 的 检查 都是没有 必要的。 关键词 :钻头磨削 ;钻头刃磨 ;牙轮钻机模型点 ;麻花钻磨削 。 1 前言 现在 在调整现有的简单锥形麻花钻磨削机器 上存在着 一些问题 , 操作者 要求很容易就能改变这些 机器不同点 的 参数, 前提是这些参数对钻削运动不重要, 如点 的 角 度 ,同时不 能对 性能 有 非常大影响 的 参数 进行 简单 直截了当 的调整, 例如通过图 Tsai and Wu 1,2 描述 的 斜距 d和 图 Fugelso 3,4 描述 的 参数 。大多数机器 在 调整 上采用试错 方式,直到可以 制成被 接受的 非特性的钻削才行, 这导致 不同 分批钻点 的形成 。 当 锥形钻头 的 制作完成 后 , 使得 很难衡量点 和 确定其模型参数。 由于 很容易测 出 点的角度 的 两倍 ,使得很 容易找到 和 ,但分 离 和 是困难的。实测横刃角包含 参数 , 不能够脱离横刃角 ,同时 不能直接测量参数 d , 从 Tsai and Wu 1 的 表 中 可以推断 出: 如果其他参数 都是知道 的 话, 横刃角度 可以从中推导出来 。 又因为 锥体模型参数 很复杂 , 使得 很难检查 这些 点,因此 首先制做出正确的点,这是很重要的 。 本文介绍了一种麻花钻磨床, 该磨床上 所有的锥钻点参数 都是 允许 重新 设置的,并保证这些参 数是 常用的 ,并且重复性好。这是因为它们是直接用垫片和盖奇块 精确 定位 的 一套钻机 , 它可以校准 参数 甚少的磨床零件尺寸 且效果很好 。 nts 3 图 1 麻钻的锥点 图 2 标准麻花钻一边的观察图 2 磨床 的 描述 图 1显示锥体模型的麻花钻点与参数半锥角( )的轴线,锥轴角( ), 斜距( s)和锥尖 到 钻探 的距离 ( d) 如图 Tsai and Wu 1,2中 所描述 。 图 2显示了圆锥钻头磨床配置标准。轴线 AA 是主轴的锥模。 是定在 30,因为沿 着 切削刃 这可 给人一个 均匀分割角的感觉 ,但横刃角不能过大,见 Fugelso 4 ;一横刃角度小于 120, 角度 固定在 29到 标准 值为 118的 点角度 ,点角度是 和 的和的两倍。 如果想要 和 有所不同,上述的 数 值应该有足够广泛的应用范围。 斜交距离 对 钻头的几何形状 有 很大的影响 ,一个斜距离 的 小小改变 就会大大改变如 5 所定义的一样的限定的 角度。增加斜交距离, 将会导致限定角度按照一定的角度增长从而超过钻孔的切削边沿的整个角度 。通常斜距离约等于网 边 厚度。 如 图 .3,斜距中心 S能由 改变 不同垫片 的 厚度 P得到准确的调整 。在横量 减去 一个 垫片 的 厚度 Pnts 4 后, 斜交距离 的数值就 等于一台机器 的常量0P。 如图 .3,通过调整 垫片 Q可以调整参数 d。垫片 P的位移 会 造成垫片 Q成直角位移, 以此来 提高 或 降低钻机的空 余间隙 。该垫片厚度 Q是 可 由 包含 钻直径 D和 d参数以下公式 得到 : c o ss in45s in2 00 dDQQ 其中 d参数是钻孔直径,因为钻孔 是放在 V型槽里的 。如果钻头被 放 在一个夹头 里,d将不是 钻孔直径。 d的数值将和 钻孔直径 的 60-90 相当 ,尽可能小而不使横刃角度过大,即大于 0133 。这一结果 使得随着剪切 角度 沿着 钻轴 进 行 切削,并使得整个角度会 尽可 能地增加。大多数现有的钻磨不容许调整这个参数,并有一个固定 的 d值,即 对 大 的钻头 仅可接受, 而对小的钻头则过大 。 如 图 2.顶部 G必须 到 锥尖 处有一个适当的 距离 J, 此时的合适角速度为 w。 J可由下式得到 : s in2 co sddJ,然后 R距离可以由 JRR 0得出: 图 3 标准麻花钻 nts 5 图 4显示由 表面 G到该基地 的 距离 R, 测量仪必须定位于沿 Z轴的 出削槽。 图 5,表示的是钻孔和其出削槽的连接 ,但是因为该 出削槽 凹 的 形状 ,使得 这 个 调整不是 很 精确。 其中 参数 的 调整 由 G的 宽度 w来进行计算,钻孔套可沿 锥轴 AA 旋转 90 左右。在 磨削 以 后 ,切削边可 达到外径测量仪接触点 ,如图 4和 5所示 。这一结果在第一原理 下 设定 w, W是由以下公式 得到 : ta n220 DWww W参数范围从零到一 个很小的 角度,不超过 15
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