1、中国地质大学 长城学院 2013 届毕业设计 原文 Commonly used grinding machine As a kind of important ultra-precision processing method， the advantage of grinding is high machining accuracy, processing materials range, almost suitable for all kinds of materials processing, grinding can get very high precision and shape a
2、ccuracy, even can reach the limit, the machining accuracy of grinding device is simple, does not need a lot of the complex mechanical and not demanding equipment precision conditions. As a super finishing one method, grinding machine is mainly used for the high precision grinding workpiece plane, th
3、e 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, magnetic grinding machine and all kinds of special grinding machine. Dise-type grinding machine p
4、oints single plate and double-tray two to double-tray grinding machine used the most common. In double-tray 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 mi
5、ll rotating, the parallel with the grinding plate can not turn, or with grinding plate under negative spin, and can move to pressure workpiece (pressure adjustable). In addition, with the grinding plate can also turning round pillar rocker to Angle, unloading workpieces. Double-tray grinding machine
6、 is mainly used for processing two parallel planes, a plane (two pressure should be increased to the workpiece accessorie), outside YuanZhuMian and sphere (with belt v-shaped slot grinding plate), etc. YuanZhuMian, because the processing and workpiece to both sliding, shall be reasonable choose to k
7、eep rolling type and arrangement plane slots Angle. Only a single plate grinding machine, used for grinding plate under the grind workpiece under plane, can make the different shapes and sizes with plate processing, grinding workpiece higher precision. Some grinding machine with the grinding process
8、 can be automatic calibration grinding plate institution. Shaft type grinding machine from positive, negative 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. Magn
9、etic grinding machine is by using magnetic force transmission to 中国地质大学 长城学院 2013 届毕业设计 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 polishing grinding remove burr effect. Special grin
10、ding machine by grinding workpiece in accordance with the different, have central hole grinding machine, steel ball grinding machine and gear grinding machine, etc. In addition, still have a kind of adopting similar centerless grinding principle unconditional grinding machine, used for grinding cyli
11、ndrical workpieces. Grinding 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 largely on whether grinding movement. In order to make the
12、 surface of workpiece grinding uniform, from the perspectives of kinematics concludes the following plane grinding best kinematics condition: firstly, workpiece with relative research of plane movement, should guarantee by grinding workpiece surface with different points on relative research are the
13、 same or similar grinding track； secondly, grinding motion is provided by the workpiece and the relative movement between developed a realization, different points on the surface of workpiece velocity should as far as possible the grinding the same； thirdly, grinding movement direction should consta
14、ntly change, grinding grain crisscross changeful, favors the surface roughness of workpiece machining, but should avoid reduced by grinding workpiece surface with different points on the relative research curvature grinding track changes too big, fourthly, grind with or pads working surface shape ac
15、curacy will reflect on the surface of workpiece, so the trajectories of workpiece with throughout the inquiry should be distributed homogeneously, favors the surface and uniform worn with research； finally, workpiece with relative research by abrasive removal direction a sports freedom, so that can
16、avoid for grinding machines guidance precision and cause errors. Grinding basic principle is to use embedded in coating or pressure with the abrasive particles on grind workpiece with and, through research in the relative movement under certain pressure for processing surface finish machining proces
17、s. The cylindrical plane grinding process is to use free grits are two plane of cylinder scraping and extrusion process of removing materials to reduce 中国地质大学 长城学院 2013 届毕业设计 cylindrical height, improve planar degree and reduce the surface roughness purpose. These remove effects through the cylindri
18、cal grinding plate with the relative movement 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. The first stage: the broken free abrasive stage. At the beginning of precision lapping ,initi
19、al 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 make more grits are competing in cutting, then on one hand consumption dimensions and cylinder of processes, this phase residual surfaces
20、grinding efficiency is higher, size, cylindrical surface roughness consumed fast. But this stage time is very short. 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 coarse gr
21、inding 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 stage elements, at this stage of the geometry precision ball improved and basically reaches
22、 corresponding requirements, the surface quality gradually enhance, roughness decline. This phase is gangqiu stability processing phases. The third stage: grits passivation and grinds light phase. In this phase abrasive most refined for o. apms m the following three fine grits, grits by the shape of
23、 the original sharp geometry without sharp edges into the sleek sphere, grinding speed greatly reduced. Passivation of grits only to micro powder cylindrical plane more trace grinding, polishing quantity Grinding quantity is about from 0.2 to 0.3 microns per hour .This stage cylindrical surface roug
24、hness further reduce and eventually reach the standard. Generally 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 smaller surface rou
25、ghness. (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 flatness and smaller surface roughness. (4) 8 glyph grinding trajectory. Suitable for flat class overhauled and small plane workpiece of grinding workpiece,
