Lee C.-S.,Sogang University |
Heo E.-Y.,Sogang University |
Kim J.-M.,Sogang University |
Choi I.-H.,CSCAM Co. |
Kim D.-W.,Chonbuk National University
Robotics and Computer-Integrated Manufacturing | Year: 2015
Abstract Electric discharge machining (EDM) is commonly used to machine precise and tiny parts when conventional cutting methods face difficulty in meeting productivity and tolerance requirements. Especially, EDM-drilling is an efficient process for the fabrication of micro-diameter deep hole even though material type is difficult to cut such as high strength steel, cemented carbide, and titanium alloys. EDM drilling is excellent for machining deep and narrow holes regardless of material hardness and location, whereas die-sinking EDM works well to machine micro-parts and perpendicular walls of die and molds. However, the electrode wear of EDM-drilling is rapid compared to that of die-sinking EDM and makes it difficult to control the electrode feed and machine precisely. Thus, this paper presents an effective model to estimate the electrode wear of EDM-drilling. To validate the proposed method, a commercial EDM drilling machine was used. Experimental results show that electrode wear amount can be predicted acceptably. © 2015 Elsevier Ltd.
Kim J.-M.,Sogang University |
Hwang S.Y.,Sogang University |
Kim D.-S.,CSCAM. Co. |
Choi I.-H.,CSCAM. Co. |
And 2 more authors.
International Journal of Mechanical and Mechatronics Engineering | Year: 2014
This research describes the performance data of the aluminum automobile wheel manufactured by wheel flow forming machine. The performance is examined after designing and operating the CNC controller which is customized for the wheel flow-forming machine. In general, the existing wheel flow forming machine simultaneously controls the 3 rollers and axis, which results in the degradation of the quality of the product due to syncing to the slowest one and slowing down in its processing speed. In order to solve this problem, multi-channel CNC controller has been developed and is able to independently control each individual roller and axis in short cycles. In order to practice the multi-channel CNC, the mutual communication of the fundamental structure of the CNC controller utilizes sync signal and each thread is applied with the sharing memory data sync method through the EtherCAT communication. When producing wheel forming by utilizing the customized CNC controller, it has been found that there had been a great improvement in processing time (productivity) and degree of precision, in comparison to the existing wheel flow-forming machine. © December 2014 IJENS.
Lee J.-H.,CSCAM Co Ltd
International Journal of Advanced Manufacturing Technology | Year: 2010
A model propeller plays important roles in the design of the marine vehicles. The cavitations, the erosion, the pressure fluctuation, and the flow are measured by the model propeller. These measurements help to create the actual marine propeller. In this paper, geometry modeling and tool path generation for a model propeller are proposed, and the hub surface and lateral surface of the wing surfaces are generated by the proposed method. Considering the characteristics of the model propeller, efficient Cutter Location (CL) data are proposed: (1) the finish machining is completed with one setup posture. (2) A four-axis machining algorithm is proposed that makes it possible to the propeller with one setup and that minimizes machining error. (3) To minimize the maximum machining load, zigzag machining and an outside-to-inside tool path are introduced. A tilting guide curve is proposed to determine the tool axis vector. A smoothly changing tool axis vector is obtained through this curve, and the calculation is simple and fast. The results demonstrate that the proposed method is useful for the manufacturing of model propellers. © Springer-Verlag London Limited 2010.