scholarly journals A Study of Profile Measurement with Zone-Plate Interferometer on Ultra Precision Machines

1992 ◽  
Vol 28 (1) ◽  
pp. 164-165
Author(s):  
Fumio KOBAYASHI ◽  
Takashi NOMURA ◽  
Kazuo YOSHIKAWA ◽  
Hatsuzo TASHIRO ◽  
Masane SUZUKI ◽  
...  
Keyword(s):  
Zone Plate ◽  
Profile Measurement ◽  
Ultra Precision ◽  
Precision Machines

Air Characteristics in Air Turbine Spindle of Ultra Precision Machines

2010 ◽  
Vol 297-301 ◽  
pp. 396-401
Author(s):  
Mehrdad Vahdati ◽  
E. Azimi ◽  
Ali Shokuhfar
Keyword(s):  
High Speed ◽  
Design Procedure ◽  
Inlet Pressure ◽  
Cylindrical Shape ◽  
Air Inlet ◽  
Wind Turbine System ◽  
Air Turbine ◽  
Ultra Precision ◽  
The One ◽  
Precision Machines

Air Spindles have been used in ultra precision machines for several years due to their advantages such as high speed rotation, low friction, and low vibration, [1]. Air spindles are widely used in these machines for producing precise work pieces. Although, spindles function on a very complicated theoretical basis, [2, 3], their structure is very simple and consists of mainly a rotor and a stator. The rotor/stator could be made of different shapes. A cylindrical shape is the one commonly in use. The spindle designed in this work has a spherical configuration. It has been designed so that it could be moved without application of electric motor and only by a wind turbine system, [4]. The spindle studied in this research uses compressed air for rotor suspension, and has an air turbine for rotating its shaft. A thin air film acts as bearing layer between rotor and stator. In design procedure, operation parameters such as air inlet pressure for turbine, air inlet pressure for bearing, diameter of turbine nuzzles, diameter of bearing nuzzles, clearance between rotor and stator and etc. have been considered, [5]. A prototype spindle has been manufactured using design criteria. The influence of above mentioned parameters have been recognized through experiments.

An Analytical Study on the Spherical Spindle of an Ultra Precision Machine for Use in Nano Machining Technology

2009 ◽  
Vol 283-286 ◽  
pp. 171-176
Author(s):  
Mehrdad Vahdati ◽  
Ali Shokuhfar
Keyword(s):  
Analytical Study ◽  
Spherical Shape ◽  
Air Pressure ◽  
Work Piece ◽  
Ultra Precision ◽  
The Common ◽  
Air Flow Velocity ◽  
Precision Machines ◽  
Common Combination ◽  
Subsequent Result

Air spindles in ultra precision machines produce rotational movements for the cutting tool or work piece. The common combination of a simple cylindrical rotor and stator is the design for most spindles. If the length of such a spindle is longer than usual, it will deviate from its stable situation and start vibrating during operation, especially in high rotational speeds. In order to overcome the vibration problem, one of possible solutions is the application of a spherical rotor and stator. The manufacturing and assembly limitations do not allow obeying the spherical shape exactly. Thus, the design has been committed according to a quasi-sphere. This form of the rotor will be more stable. The subsequent result of stability improvement will be less air pressure and power consumption. There are some specific characterizations of the spindle which must be calculated for the spherical case. For this purpose a computer model of the object was made. Then, the model was put under finite element study to find the best air pressure and air flow velocity condition.

scholarly journals Highly Accurate Digital Processing of Large Stroke Guideway with an Optical Material-Corning Code 7972

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3809
Author(s):  
Hanqiang Zhang ◽  
Yifan Dai ◽  
Tao Lai
Keyword(s):  
Edge Effect ◽  
High Frequency ◽  
Digital Processing ◽  
Profile Measurement ◽  
Frequency Error ◽  
Magnetorheological Finishing ◽  
Technology Process ◽  
Ultra Precision ◽  
Grinding Tool ◽  
Surface Figure

Currently, meter-long guideways rarely achieve an accuracy of dozens of nanometers due to processing difficulties such as the material and the edge effect. In this paper, we focus on this problem and propose a set of optimization processing methods to cope with it. In the grinding stage, a grinding tool is designed to improve the reciprocating processing and address the problem of warping; in the polishing stage, three different processes are compared, and the combination of magnetorheological finishing technology and the polyurethane disc technology process is purposed to reduce the polishing cycle and improve the surface figure accuracy. Moreover, through the combined process of magnetorheological finishing and smoothing, the edge effect and medium- and high-frequency error are essentially suppressed. The meter-long guideway is achieved with an accuracy of dozens of nanometers. Although the sizes of surface A/C and B/D are 1000 mm × 240 mm and 1000 mm × 160 mm, the surface figures are 20.33 nm, 22.78 nm, 39.23 nm and 26.58 nm RMS (Root Mean Square), respectively. The nanometer accuracy guideway is critical to an ultra-precision machine tool. Finally, the X-axis straightness of the profile measurement system formed by the guideway reaches 200 nm/600 mm.

A Study on Design of Ultra-Precision Micro-Feed Stage

2006 ◽  
Vol 315-316 ◽  
pp. 131-135
Author(s):  
Q. Zhang ◽  
Ze Sheng Lu
Keyword(s):  
Design Method ◽  
Dynamic Performance ◽  
Design Procedure ◽  
Performance Parameters ◽  
Element Analysis ◽  
Flexure Hinges ◽  
Ultra Precision ◽  
Positioning Technique ◽  
Precision Machines ◽  
Geometrical Dimensions

Ultra-precision positioning technique has become one of the important parts in the development of precision machines. Flexure stage driven by piezoelectric actuator (PZT) has been used widely as micro-feed installation because they have many advantages, such as: driving directly, fine displacement resolution, no friction or spacing. This paper designed a micro-feed stage driven by PZT using clinograph mechanism, analyzed the influence of flexure hinges on the static and dynamic performance of micro-feed stage based on finite element analysis. The design procedure was presented by which we can determine the geometrical dimensions of flexure hinge easily and achieve desired performance parameters of the stage, and the effectiveness of the design method was validated by experiment.

Wear of Coated Carbide Tools in the Ultra-Precision Machining of Stainless Steel

2005 ◽  
Author(s):  
W. Y. H. Liew ◽  
X. Ding
Keyword(s):  
Stainless Steel ◽  
Cutting Tool ◽  
Cutting Speed ◽  
Precision Machining ◽  
Mould Insert ◽  
Ultra Precision ◽  
Coated Carbide ◽  
Precision Machines ◽  
Coated Carbide Tools ◽  
Steel Mould

Ultra-precision machines are widely used to turn aspherical profiles on mould inserts for the injection moulding of optical lenses. During turning of a profile on a stainless steel mould insert, the cutting speed reduces significantly to 0 as the cutting tool is fed towards the center of the machined profile. This paper reports on experiments carried out to study the wear of uncoated, PVD-coated and CVD-coated carbide tools in the ultra-precision machining of STAVAX (modified AISI 420 stainless steel) at low speeds.

Structural Analysis for an Ultra-Precision Machine Slide by FEM Based on Applied Mechanics

2012 ◽  
Vol 496 ◽  
pp. 321-324
Author(s):  
Bin Gao ◽  
Jing Hua Zhu ◽  
Wen Chang Lang
Keyword(s):  
Structural Analysis ◽  
Machine Tool ◽  
Permanent Magnet ◽  
Applied Mechanics ◽  
Full Load ◽  
Linear Motors ◽  
Precision Machine ◽  
Analytical Results ◽  
Ultra Precision ◽  
Precision Machines

Micro/nano machining becomes more and more important and popular. Ultra-precision machines are the fundamentals. Aiming at design and developing an ultra-precision machine tool for micro/nano machining, the slide, one of the most important part of the machine has been analyzed by FEM. The software Abaqus has been used for the analysis. Based on the full load created by the coils and permanent magnet of the linear motors, the kinetics characteristics have been analyzed. According to the analytical results, the slide structure has been optimized to fulfill the requirements of the developed micro/nano machine tool.

The Influence of External Load and Air Pressure on Air Slide Table Performance of Ultra Precision Machines in Nano Machining

2009 ◽  
Vol 283-286 ◽  
pp. 177-182
Author(s):  
Mehrdad Vahdati ◽  
Ali Shokuhfar ◽  
Meysam Bagheri
Keyword(s):  
External Load ◽  
Air Pressure ◽  
Ultra Precision ◽  
Load Location ◽  
Air Table ◽  
Precision Machine Tools ◽  
Straightness Error ◽  
Air Spindle ◽  
Precision Machines ◽  
Influential Parameters

Ultra precision machine tools are used in nano machining technology. Two main assemblies creating rotational and linear motion, called air spindle and linear air table are used in these machines. The linear air table has been simulated experimentally like a linear air bearing. This bearing moves in the main direction, X, while it has straightness error motions in Y and Z directions. The error values vary due to different parameters. This investigation deals with the influential parameters and their proportion in the error value. As far as the two mating surfaces are separated by a thin layer of pressurized air, the air pressure, location and amount of external load, are some of the parameters which have been studied. Results show that the more air pressure, the more stability and stiffer table. There will be less error motions as well. The error amount is not the same in X and Y directions. Finally, in order to have linear stiffness, the optimum air pressure, external load, and load location have been decided.

Design of Moving Components of an Ultra Precision Machine Tool for Nanometric Machining

2007 ◽  
Vol 553 ◽  
pp. 232-238
Author(s):  
Mehrdad Vahdati ◽  
Ali Shokuhfar
Keyword(s):  
Machine Tool ◽  
Surface Texture ◽  
Work Piece ◽  
Effective Parameters ◽  
Precision Machine ◽  
Wide Range ◽  
Ultra Precision ◽  
Air Table ◽  
Air Spindle ◽  
Precision Machines

Ultra precision machines are used for very precise machining as well as small parts. Due to their application, the accuracy of products has been upgraded in recent years. Thus, dimensional accuracies could be compared with surface texture dimensions like roughness and etc. In order to attain dimensions with surface texture accuracy, usually micro/nano meter, it is necessary to adopt ordinary machining technologies with micro/nano techniques. This measuring by adoption leads to nano-machining. Nano-machining researches deal with all three basic components of, machine tools, work piece, and cutting tool, which have fundamental importance for development of this technique. Despite of wide range of possible researches, only part of design points of ultra precision machines have been considered in this report. Air operated systems, like air slide table, and air spindle are examples of ultra precision machine tool components. These two components have been analyzed for some of their characteristics. Experiments have been planed to extract the relationship between stiffness, employing some of the effective parameters such as air pressure and air gap. The results describe the performance condition of air table and air spindle under different loadings.

Reproducibility of a Nanometre Accurate Moving-Scale Measurement System

2014 ◽  
Vol 613 ◽  
pp. 37-42 ◽  
Author(s):  
Niels Bosmans ◽  
Jun Qian ◽  
Dominiek Reynaerts
Keyword(s):  
Measurement Uncertainty ◽  
Measurement System ◽  
Machine Tools ◽  
Uncertainty Budget ◽  
Experimental Setup ◽  
Thermal Drift ◽  
System A ◽  
Ultra Precision ◽  
Precision Machines

A dedicated experimental setup has been designed and built up for determining the reproducibility of a 1-DOF moving-scale measurement system. A 3-DOF moving-scale system would enable the measurement of the position of a workpiece table moving in three perpendicular directions with minimized Abbe-offset. This allows normal machine tools and CMMs to match or even surpass the accuracy of ultra-precision machines. An uncertainty budget indicates that the 1-DOF moving-scale system can obtain a measurement uncertainty of 18 nm. Thermal drift is the largest contribution to the measurement uncertainty and should be accurately determined.

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