RESEARCH ON MODELING AND CHARACTERISTICS OF THE SPINDLE DYNAMIC COUPLING ABSORBERING SYSTEM OF A SUPER-PRECISION SURFACE GRINDING MACHINE

The bearing is described by constrain matrix, and the spindle system of a NCsurface grinding machine is simplified as elastic-coupling beam, then modal synthesis method is usedto establish the dynamic model of beam. Moreover, the response of the end of rotor is analyzed, andthe natural frequency, principle mode and other dynamic characteristics of the coupling system arestudied, the law of bearing stiffness to coupling frequency and amplitude of rotor is also found.Finally, according to the actual condition, a dynamic absorber is designed. The simulation andexperimental results show that the amplitude of spindle can be declined effectively when the dynamicabsorber is attached.

Theoretical Study on Non-transmission High Efficient Parallel Camber Grinding Machine

Be directed against the development trend of modern CNC grinding machine towards high precision and high efficiency, some general weaknesses of existing camber grinding machine are analyzed in detail. In order to develop new type CNC camber grinding machine that can grind complex die, and genuinely achieved accurate feed and high efficient grinding, a new type camber grinding machine is put forward, called non-transmission virtual-shaft CNC camber grinding machine. Its feed system is a parallel mechanism that is directly driven by linear step motor. Therefore, traditional transmission types, such as the ball lead-screw mechanisms, the gears, the hydraulic transmission system, etc. are cancelled, and the feed system of new type CNC camber grinding machine can truly possess non-creep, good accuracy retentiveness a wide range of feed-speed change, high kinematical accuracy and positioning precision, etc. In order to realize that the cutting motion is provided with high grinding speed, step-less speed variation, high rotational accuracy, good dynamic performance, and non-transmission, the driving technology of hollow rotor motor is applied to drive the spindle of new type grinding machine,thus leading to the elimination of the transmission parts of cutting motion. The principle structure model of new type camber grinding machine is advanced. The selection, control gist and driving circuit line of the linear step motor are expounded. The main technology characteristics and application advantages of non-transmission virtual-shaft CNC camber grinding machine are introduced.

YK 7425 GEAR GRINDING MACHINE

This is a newly developed product,CNC gear grinding machine basedon original Y 7125 A large planargear grinding machine, produced by theQinchuan Machine Tool Works. It is chieflyused for grinding the involute tooth profilesof gear-shaping cutters, gear-shaving cuttersand master gears, and is also used for grindinghigh precision spur and helical gears. It issuitable for the departments of the automobiles,tractors, aircraft, machine tools and toolmanufacturing industries.

MODELM1432C——UNIVERSAL CYLINDRICAL GRINDING MACHINE

The new machine features high precision,excellent rigidity and practical structure.It is made by the Beijing No.2 MachineTool Works with 40 years of experience inproducing high-precision cylindrical grindingmachines.It is already close to the standardof high precision machine tools in terms ofmachining accuracy,therefore its variousfeatures are distinctly better than previousmodels.Since being put on the market,it hasbeen well received by users. The machine is used in machineprocessing shops,tool shops and repair shopsto grind internal and external cylindricalsurfaces of cylinders and tapers.

YM7132A——GEAR GRINDING MACHINE WITH CONICAL GRINDING WHEEL

The YM7132A gear grindingmachine with a conical grindingwheel is used for grindingcylindrical spur and helical involutegears,especially for hardenedprecision gears of small andmedium sizes.

YK7232——GEAR GRINDING MACHINE WITH WORM GRINDING WHEEL

The machine is used for precisiongrinding of hardened cylindricalgears with medium module inbatches for the industries ofaircraft,automobile,machine tool,gear box and various transmissiondevices.

YK7250 Gear Grinding Machine With Worm-Grinding Wheel

The YK7250 gear grinding machine with worm grinding wheel is manufactured by the Qinchuan Machine Tool Group Co., Ltd. in Baoji City, Shaanxi Province.

Development of an oscillating grinding machine tool based on error analysis

Oscillating grinding machine tool is the core equipment when machining crankshaft pin journal,which directly determines the final quality.This paper describes the development of an oscillating grinding machine tool based on error analysis.First,the error analysis of oscillating grinding for crankshaft pin journal is carried out,including the effect on machining accuracy caused by each error and corresponding error sensitivity.The results show that the tracking error of X-axis has the greatest influence on the grinding accuracy of pin journal,thus,the grinding carriage feed system is the critical component of an oscillating grinding machine tool,which should be given priority during the development process.Next,the development of an oscillating grinding machine tool is described.The whole structure is given,and the grinding carriage feed system is emphatically presented involving drive mode and assembly method.Other components of the oscillating grinding machine tool are also introduced.Finally,some grinding experiments are performed on the prototype,and the results show that all workpieces are qualified under different conditions,which verify the performance of the developed oscillating grinding machine tool.

Research of Plane Grinding under Combined Movement of X-Y Axis

There are many parameters which can influence plane grinding. It is a situation in high workload and poor realizability to find the optimization parameters of the grinding by using experimental method. Taking X-Y linkage plane grinding as the platform, influence of grinding quality with 4 factors including initial diameter of the abrasive, initial phase angle, lapping plate ＆ workpiece speed ratio and X-Y linkage workbench through simulation is studied. The results show that initial radius vector of the abrasive basically has not effect on grinding trace. When speed ratio between lapping plate with workpiece is decimal the grinding trace seems much better. The significant influence of grinding quality can made by straight and helical X-Y linkage motion on workbench

Study of CNC Grinding Machining Method About Isometric Polygon Profile

The formed principle and CNC grinding machining method of isometric polygonal profile are studied deeply and systematically. Equation about section curve of isometric polygon profile is set up by means of geometric principle. With the use of differential geometry theory, the curve is proved to be with geometric feature of convex curve. It is referred to as Isometric Polygonal Curve (IPC), because that is a kind of convex curve on which the distance between any parallel tangent lines is equal. Isometric Polygonal Profile (IPP) or Isometric Polygonal Cone Profile (IPCP) or Isometric Polygonal Topless Cone (IPTC) is formed with the IPC and straight line as generating curve. But the machining and measuring of the IPCP are so inconvenient that it has little value. Keeping in mind the characteristic of the IPP and IPTC, this paper puts forward the program method of CNC grinding machining. Isometric polygonal profile connection is a kind of polygonal profile connection. It has the superiority over keys (prismatic key & spline etc), and can be suit for the situations such as high rotative velocity, large torque, high precision, and small fixed room and vibration. Nowadays, some countries such as America, Russia, German and Switzerland applied CNC machining to the machining of polygon surface coupling parts, which makes their applications in machine productions such as motor engine, heavy machine increase day by day. But reports about concrete machining technology of isometric polygonal profile and programming of CNC machining program are very few. CNC grinding of the IPP and IPTC is one kind of the precision machining technology. It is of great importance to the popularization of the IPP and IPTC connection. From the forming mechanism, we can see that the machining and measuring of the IPP and IPTC are convenient, and therefore they have the value of the popularization. But the machining and measuring of the IPCP are so inconvenient that it has little value. In the programming the CNC grinding of the IPP and IPTC, it is more reasonable to calculate the coordinate of node according to the approaching method of equal error arc. According to the method of CNC grinding mentioned above to design the grinding machine, the structure is simple and of economical and practical.

FORMING AND PRECISION MACHINING TO NANOMATERIALS LUMP

The technology of forming and machining lump nano-materials has beeninvestigated. Grinding, abrasive machining test has been conducted to Fe, Co, Ni and Al lumpnano-materials. Experiments have been done to measure grinding force, grinding thermal, machiningroughness and micro-hardness. Image analysis is carried out by metallographic and scanning tunnelmicroscopic microscope. Researches provide the basis data for forming and machining lumpnano-materials.

RESEARCH OF NEWTECHNOLOGIES IN GEAR-MACHINING

This paper describes the basic principles and the researched technology levels of involute gear forming-grinding technology in a economic way,and special shaping technology,cycloidal gear machining technology and enveloping electrospark machining technology of internal gear harden surfaces.

Detection of subsurface defects of fused silica optics by confocal scattering microscopy

A non-destructive technique for subsurface measurements is proposed by combining light scattering method with laser confocal scanning tomography. The depth and distribution of subsurface defect layers are represented in term of scattered light intensity pattern, and three types of fused silica specimens are fabricated by different grinding and polishing processes to verify the validity and effectiveness. By using the direct measurement method with such technique, micron-scale cracks and scratches can be easily distinguished, and the instructional subsurface defect depths of 55, 15, and 4 μm are given in real time allowing for an in-process observation and detection.

Experimental investigation on laser-induced surface damage threshold of Nd-doped phosphate glass

Nd-doped phosphate glass is the dominant amplifier material used in solid state high average power laser systems.Surface imperfection and subsurface damage（SSD）of the glass,resulting from the optical fabrica-tion process,limit the increment of laser system energy output.Thus,it is important to enhance the surface damage threshold of Nd-doped phosphate glass surface.The influence of abrasive size,polishing powder,grinding mode,and chemical treatment on the laser-induced damage threshold（LIDT）of Nd-doped phos-phate glass surface is investigated.Results show that the LIDT is affected little by different polishing powders and grinding modes.The LIDT correlates with the abrasive size,which produced different depths of SSD.A suitable acid etching treatment can remove the imperfection and the SSD for improving the LIDT of Nd-doped phosphate glass surface.The combination of several effective techniques and methods,which are low-cost and practical,should be useful to enhance the LIDT of Nd-doped phosphate glass surface.