• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1227-1230
• /
• 2003

A roughing process is one of the most important and indispensable shoe manufacturing processes of various types of shoes. This basic process to rough the upper of the shoe is studied to improve the productivity and to reduce the processing time. In this study, the CAM system for shoe roughing is developed. The B-spline surface generated by the developed CAM system ignores the small inclinations of the real roughing surface because the developed roughing tool has potential to rough the roughing surface of the shoe properly. The roughing tool roughs the roughing surface using its side along the generated tool paths. The generated NC codes were applied to 5-axis polishing machine for the test. Experimental results show good evaluation result. The upper of the shoe is roughed properly along the roughing path line and the roughing surface was good to cement the outsole of the shoe.

• Journal of the Korean Society for Precision Engineering
• /
• v.22 no.7 s.172
• /
• pp.122-129
• /
• 2005

Shoe with leather upper such as safety and golf shoe requires a roughing process where the upper is roughed fur helping outsole to be cemented well. It is an important and basic process for production of leather shoe but is not automated yet. Thus, there are problems that the defect rate is high and the quality of roughed surface is not uniform. In order to solve such problems, the interest in automation of roughing process is being increased and this paper introduces CAM system for 5-axis automatic roughing machine as one part of automation of roughing process. The CAM system developed interpolates a B-spline curve using points measured from the Roughing Path Measurement System. The B-spline curve is used to generate the tool path and orientation data fer a roughing tool which has not only stiffness but also flexibility to rough the inclined surface efficiently. For productivity, the upper of shoe is machined by side of the roughing tool and tool offset is applied to the roughing tool for machining of inclined surface. The generated NC code was applied to 5-axis polishing machine for the test. The upper of shoe was roughed well along the roughing path data from CAM and the roughed surface was proper fur cementing of the outsole.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.568-571
• /
• 2004

This paper presents an efficient 5-axis roughing method for centrifugal impeller. The efficient roughing is minimization of cutting time through minimizing tool tilting & rotating motions. Roughing tool path plan consists of the three steps. First, machining areas are divided into sub cutting regions using ruling lines. The biggest tool diameter is, then, determined for each region. Finally, tool paths are generated after fixing the tilting and rotating axis of 5-axis machine. Experimental results showed that the proposed roughing plan considering the divided machining regions is more efficient than the conventional methods.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.27 no.11
• /
• pp.1917-1924
• /
• 2003

This paper proposes a roughing path generation method fer machining impeller with 5-axis machining center. Traditional researches are focus on finishing for machining impeller. To achieve efficient machining, roughing method must be studied. The proposed method consists two steps : One is to select optimal tool size and tool attitude by dividing cutting area into two regions to reduce cutting time. The regions are automatically divided by character point on the geometry of impeller blade. After dividing, the tool of the optimal size is selected for each divided region. The other is avoidance of tool interference. Tool interference in cutting areas is avoided by checking the distance between tool axis vector and ruling line on blade surface or approximated plan between ruling line. Using this method, the cutting time is reduced efficiently.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.7 s.196
• /
• pp.60-68
• /
• 2007

This paper presents an efficient 5-axis roughing method for centrifugal impeller. The efficient roughing is minimization of cutting time through minimizing tool tilting and rotating motions. To minimized cutting time, machining area is divided into sub-cutting regions using control points on hub curves and shroud curves of blade used to design and analyze centrifugal impeller. For sub-cutting regions, diameters of cutting tools are determined as big as possible. Then, tool paths are generated with the tilting axis and rotating axis of 5-axis machine limited and fixed, which can give more efficient machining speed and machining stability than the conventional methods. Experimental results show that the proposed method is more efficient than the conventional methods to mill with the only one cutting tool without dividing area and the previous methods to mill with simultaneous 5-axis processing with dividing area.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1994.04a
• /
• pp.187-196
• /
• 1994

This study deals with roughing planning by cross sectional information generated from sculptured surfaces. Bicubic Bezier surface is adopted as sculptured surfaces in this paper. The system consists of 3 pstyd : 1) modeling sculptured surface, 2) reconstruction of cross-section in 2D coordinates, 3) determination of roughing tool path with structural data. The system is developed by using BIM-PC in the environment of Auto CAD R11, AutoLISP and MetaWare C. The proposed system shows an efficient algorithm for roughing planning with cross sectional information.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.398-401
• /
• 2001

This paper presents rough cutting pat고 drilling. This method has differences from conventional method which uses boundary curve by intersecting object to machine and each cutting plane. Die-cavity shape is drilled in z-map, we select various tool and remove much material in the short time. as a result, this method raise productivity. The major challenges in die-cavity pocketing include : 1)finding an inscribed circle for removing material of unmachined regions, 2) selecting optimal tool and efficiently arranging tool, 3) generating offset surface of shape, 4) determining machined width according to the selected tool, 5) detecting and removing unmachined regions, and 6) linking PJE(path-joining element). Conventional machining method calling contour-map is compared with drilling method using Z-map, for finding efficiency in the view of productivity.

• KSTLE International Journal
• /
• v.3 no.1
• /
• pp.17-22
• /
• 2002

Roughing of tool steel in its hardened state represents a real challenge in the die and meld industry and process improvement depends on research of tool material, coating technique, and lubrication. However, roughing of hardened steels generates extreme heat and without coolant flooding, tool material cannot withstand the high temperature without choosing the right tools with proper coating. This research conducted milling tests using coated ball end mills to study effects of cutting conditions and geometric parameters of ball end mills on the machinability of hardened tool steel. KP4 steel and STD 11 heat treated steels were used in the dry cutting as the workpiece and TiAIN coated ball end mills with side relief angle of 12$^{\circ}$ was utilized in the cutting tests. Cutting forces, tool wear, and surface roughness were measured in the cutting tests. Results from the experiments showed that 85 m/min of cutting speed and 0.32 mm/rev of feed rate were optimum conditions for better surface finish during rough cutting and 0.26mm/rev with the same cutting speed are optimum conditions in the finish cutting.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.18 no.11
• /
• pp.89-95
• /
• 2019

In this research, the effect of roughing on tool load through bottom-up machining is investigated through actual machining. Generally, through the use of high-speed machining technology, machining methods, such as general roughing, operate by deepening the cutting depth for as long as the tool is able to withstand it, giving a slower feed rate, less cutting depth, and faster feed. However, when the cutting depth is deep, there is a problem in that the stepped shape of the cutting area is increased (e.g., by the shaking of the tool or the chipping load). However, if the cutting is performed less, the cutting time becomes relatively long. To compensate for these drawbacks and extend the service life of the tool, economic efficiency needs to be secured.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.15 no.5
• /
• pp.79-84
• /
• 2006

In modem manufacturing, many products that have geometrically complicated features, including three-dimensional sculptured surfaces, are designed and produced. In the production of these complex-shaped mechanical components, e.g. automobile dies, molds, and various engineering applications, the ball-end milling process is one of the most widely used NC machining processes that consists of roughing, semi-finishing and finishing. In semi-finishing, cusps remained after roughing according to the used tools that have two patterns of stairs and wave shapes. These cusp shapes have air-cut in cutting and instability caused by high cutting speed that affects the cutting characteristics such as cutting force and tool wear. Cutting characteristics are measured and analyzed through cutting force, FFT analysis of cutting force and tool wear along cutting length according to low tool paths with same metal removal rate. As a results of the experiments, this study suggests the optimal conditions of tool path and cutting direction. This approach for the cutting characteristics of semi-finishing provides a useful aid for the productivity and efficiency improvements of NC machining processes.