Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Society for Precision Engineering
Journal Basic Information
Journal DOI :
Korean Society of Precision Engineering
Editor in Chief :
Volume & Issues
Volume 13, Issue 12 - Dec 1996
Volume 13, Issue 11 - Nov 1996
Volume 13, Issue 10 - Oct 1996
Volume 13, Issue 9 - Sep 1996
Volume 13, Issue 8 - Aug 1996
Volume 13, Issue 7 - Jul 1996
Volume 13, Issue 5 - May 1996
Volume 13, Issue 4 - Apr 1996
Volume 13, Issue 3 - Mar 1996
Volume 13, Issue 1 - Jan 1996
Selecting the target year
MACHINE TOOL TECHNOLOGY; THE PRESENT AND THE FUTURE(10)
Kahng, Cheol-Hui ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 5~21
A Study on the Characteristics of Wire-Cut Electrical Discharge Machining for STD-11 Alloy Steel and P-20 Tungsten Carbide Alloy
Lee, Jae-Myeong ; Heo, Seoung-Jung ; Kim, Won-Il ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 22~28
From the experimental study of Wire-Cut Electric Discharge Machining of STD-11 alloy steel and P-20 tungsten carbide, the characteristics such as hand drum form and discharge gap have been observed and evaluated for various conditions. Hand drum form can be improved when gap have been observed and evaluated for various conditions. Hand drum form can be improved when gap voltage and spark cycle become smaller, thickness become thinner, wire tension become larger and the no of cutting increases. When 60mm thickness tungsten carbide is cut in normal condition, hand drum form becomes larger due to the low conductivity machining allowance become slightly larger when peak discharge current and gap voltage become larger, or wire tension becomes smaller. Under the same condition, machining allowance of tungsten carbide is larger than alloyed steel by 1/100mm.
Development of PC Controled Automatic Cutting System
Kim, Sang-Hun ; Chung, Kyung-Ryul ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 29~37
In this study, PC controlled CNC automatic cutting system is developed. Technological introduction of the control process and the computer programming has made possible not only the automatic control for cutting processing unit but also the easy-to-use graphic software that enables the cutting process. This program involves shape part drawing and amendment, pattern reading and saving, reading Autocad file, nesting process, kerf compensation, automatic cutting path generation, NC file conversion and motor control. Software is devided into 3 modules for easy work. First step enables drawing, amendment and pattern making, followed by automatic nesting and cutting path generation with kerf compensation. In the final step, drawing data is transmitted for the resulting automatic cutting processes. This software would be applicated in gas cutting and textile cutting so that it improves the productivity of cutting process.
CAD system development for design of limit gauges
Lee, Dong-Ju ; Lee, Kwang-Gil ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 38~44
The CAD system for design and drawing of limit gauges was constructed and developed. This system was made by Visual Basic program. Using this system, drawings together with concerned data for the manufacturing of limit gauges are generated on the screen, file and printer. The data base was constructed by referring handbooks, textbooks, relevant standards and regulations. This system was proved a powerful tool for design and drawing of limit gauges by actual applications. The output drawings from this system are in good agreement with the drawings and data of the concerned standards and regulations.
A Study on the Evalution of Rotational and Linear Movement Error in Thread Grinder
Park, Cheol-U ; Yoon, Yeong-Sik ; Lee, Sang-Jo ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 45~52
It is one of the important causes that the precision of the thread grinder decide the machining errors of the ball screw. The approach described in this study demonstrates how the dominant causes of the inaccuracies in thread grinding system can be determined. To evaluate the machining error of thread grinder, rotary encoder is allocated to spindle shaft and master screw for measuring the rotational transfer error between spindle shaft and master screw and the laser measuring system is used for checking the movement error.
The Effect of Cutting Edge on the Surface Roughness In Cutting Brittle Materials
Kim, Joo-Hyun ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 53~61
A clear understanding of the surface formation mechanism due to cutting is very important to help produce a good quality surface. Much of the roughness along the length of a bar being cut in a lathe can be explained in terms of macroscopic tool shape and feed rate. However, the roughness along the direction of cutting requires a different explanation. The formation of surface roughness is a problem in flow and fracture of materials in the vicinity of the tool edge. On a microscopic scale the cutting edge is rounded because it is impossible to grind a perfectly sharp cutting edge. Even if a perfectly sharp cutting edge were obtained it would soon become dull as a result of rapid breakdown and wear of the cutting edge. A research project is proposed in which in the main object is to model the surface formation mechanism due to cutting. The tool was assumed to be dull, that is, its edge has a finite radius. In order to study the effect of the radius of cutting edge on the surface formation, tools having different cutting edges were used. For orthogonal cutting experiment, cast iron and glass were chosen as brittle materials. Plowing forces acting in the cutting edge were estimated and its effect on the surface roughness was studied by observing the machined surface using optical microscope.
Optimal control of a flexible robot arm using singular perturbation model
Han, Ki-Bong ; Lee, Shi-Bok ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 62~68
Linear controllers, such as LQG/LTR controller, have been investigated to control flexible link manipulators. The performance and complexity of these depend largely on the linearized model upon which the controller is designed. In this study, singular perturbation model is tested in designing a LQG/LTR controller for a flexible link manipulator. The order of the resulting controller is much lower than the one based on a full model. Through numerical study, it is shown that the performance of the proposed controller reaches reasonably to the one based on the full model.
A Study on performance analysis of screw rotor profiles
Choi, Sang-Hoon ; Kim, Dong-Hyun ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 69~77
To design high-effective profile in screw rotor profile using in screw compressor, we design the symmetric type changing the number of lobes and the non-symmetric type changing the neighbourhood of the top point of lobe. Then, we calculated the performance value of profile according to the scale of these non-symmetric's wrap angle. We had the results as follows. 1. About the non-symmetric case, the larger a wrap angle is the shorter seal line is and the smaller blow hole is, thus we know what the large wrap angle profile is better than the small one. 2. We know what the non-symmetric profile is better than the symmetric profile in the result of the compare of seal line's length, blow hole's area, volume curve. 3. About the non-symmetric case, the deformation of the neighbourhood of lobe's top point of the rotor profile has a large effect upon the increase of performance because the length of seal line became short and the area of blow hole is small.
A Study on the Ultraprecision Cutting of Aluminium Alloy by the Diamond Tool
Yu, Ki-Hyun ; Mun, Sang-Don ; Yu, Jong-Sun ; Kim, Tae-Young ; Seo, Nam-Seob ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 78~83
This paper presents the characteristics of surface roughness and cutting force in ultraprecision cutting of aluminium alloy using natural diamond tools whose edge radii are smaller than those of tools made of other materials. The feed rate and depth of engagement were set to be a micrometer order. After measuring the surface roughness of machined surface and cutting force for each cutting condition, the relations between the surface quality and its condition were investigated qualitatively. If the feed rate was under a certain limit, the machined surface quality was deteriorated unexpectedly. This is supposed to have happened due to vibration leading its condition to abnormal one. In a certain situation the machined surface roughness by a natural diamond tool was inferior to that made by a carbide tool whose cutting edge radius is larger. This is supposed to be caused by not normal machining but burnishing effect.
Mechanics of Diamond Blade Sawing
Seo, Young-Il ; Choi, Hwan ; Lee, Jong-Chan ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 84~90
A theoretical analysis is presented on the mechanics of diamond blade sawing. The normal and tangential components of cutting force are calculated. Experimental results are also presented, which show the effects of cutting variables such as cutting speed, feed speed, cutting area, and concentration of diamond blade on the cutting forces. The experimental results are found to be in good agreement with those predicted by the analytical calculation.
A Study on the Cold Forging Design System Using Neural Networks
Kim, Young-Ho ; Bae, Won-Byong ; Suh, Yun-Soo ; Park, Jong-Ok ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 91~97
This paper deals with a cold forging design system by which designers can determine desirable plans of cold forging design even if they have little experience. In this system, neural networks are used to transform qualitative knowledges to quantitative knowledges. The neural network is learned with three parts which are most important in cold forging design - undercut, narrow hole, sharp corner. The capabilities of the system are illustrated through an example of forging design.
On Error Modeling and Compensation of Machine Tools
Song, Il-Gyu ; Choi, Young ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 98~107
The use of composite hyperpatch model is proposed to predict a machine tool positional error over the entire work space. This is an appropriate representation of the distorted work space. This model is valid for any configuration of 3-axis machine tool. Tool position, which is given NC data or CL data, contains error vector in actual work space. In this study, off-line compensation scheme was investigated for tool position error due to inaccuracy in machine tool structure. The error vector in actual work space is corrected by the error model using Newton-Raphson method. The proposed error compensation method shows the possibility of improving machine accuracy at a low cost.
Study on the Forging of Splines with Hollow and Solid Billets
Cho, Hae-Yong ; Choi, Jong-Ung ; Min, Gyu-Sik ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 108~115
Forging of trapezoidal spline, serration and square spline with solid cylindrical billets and hollow one has been investigated by means of upper bound method. Kinematically admissible velocity fields for forging of splines have been proposed in this study. The half pitch of spline has been divided into several deformation regions. The neutral surface is introduced into forging of splines with flat punch and, for each step, it is assumed as a circle with its radius
. Upper bound solutions obtained by proposed kinematically admissible velocity fields are useful to predict the loads for forging of splines.
Analysis of die wear in wire drawing with temperature effect
Kim, Byeong-Min ; Cho, Hae-Yong ; Kim, Tae-Hyeong ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 116~122
In forming processes, die failure must be considered before die design. One of the main reasons of die failure in industrial application of metal forming technologies is wear. The die wear affects the tolerances of formed parts, metal flow and costs of processes etc. The only way to control these failures is to develop methods which allow prediction of the die wear and which are suited to be used in the design state in order to optimize the process. In this paper, wire drawing processes were simulated using the rigid-plastic finite element method and its results were used for predicting the die wear by Archard's wear model. The effects of the temperature rising on the wear profiles of die were also investigated. The simulation results were compared with the measured die profiles.
A Study on the Design of Throw-away Cutting Tool System for Deep Grooving or Cut-off Machining
Kim, Hyeung-Chul ; Lee, Woo-Young ; Namgung, Suk ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 123~130
The procedure on the design of a new tungsten cabide throw-away cutting tool system for deep grooving or cut-off machining is suggested. For relieving the maximum stress level at the corner radius of the blade holder, the finite element method is used. Also the pulling test device is proposed for measuring the holding force of the insert between the blade holder and the insert considering the materials in contact and configuration parameters of the holder.
An Efficient Calibration Procedure of Arc Welding Robots for Offline Programming Application
Borm, Jin-Hwan ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 131~142
Most industrial robots cannot be off-line programmed to carry out a task accurately, unless their kinematic model is suitably corrected through a calibration procedure. However, normal calibration is an expensive and time-consumming precedure due to the highly accurate measurement equipment required and due to the significant amount of data that must be collected. This paper presents a simple and economic procedure to improve the efficiency of robot calibration especially for arc welding application. To simplify the measurement process, an automotic data measurement algorithm as well as a simple measurement device are developed. Also, a calibration algorithm which can automatically identify the independent model parameters to be estimated is presented. To demonstrated the simplicity and the effectiveness of the procedure, experimental studies and computer simulations are performed and their results are discussed.
Numerical Study on Chaotic Dynamics of Repeated Impacts with Friction - Vibratory Bowl Feeders
Han, In-Hwan ; Lee, Yun-Jae ; Yoon, Koo-Young ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 143~152
The vibratory bowl feeder is the most versatile of all hopper feeding devices for small engineering parts, and the typical nonlinear dynamic system experiencing repeated impacts with friction. We model and analyze the dynamic behavior of a single part on the vibrating track of the bowl feeder. While the previous studies are restricted to the sliding regime, we focus our analysis on the hopping regime where the high conveying rate is available. We present the numerical analysis results for conveying rate and frictional impact process both in periodic and chaotic regimes. We examined the dynamic effects from the variation of several physical parameters, and presented the important features for the design of the vibratory bowl feeder. This research holds much potential for leverage over design problems of wide range of mechanisms and tools with repeated collisions.
Disassemblability of Mechanical Parts in Automobile for Recycling of Materials
Mok, Hak-Soo ; Chung, Hyun-Kyo ; Park, Ju-Hyung ;
Journal of the Korean Society for Precision Engineering, volume 13, issue 1, 1996, Pages 153~166
It is important to make use of the scrapped materials, components, and subassemblies which have still high quality and reliability in an out of service cars from the view point of economy and environment. In this paper, we studied geometrical and material characteristics of parte, subassemblies and joining elements to be assembled in designing a car. The mechanism of disassembly between parts and subassemblies is analyzed in order to disassemble recyclable parts in a scrapped automobile. The weak points of disassembly process are analyzed and the parameters for disassemblability are defined. And the guidelines for disassemblability are developed.