1.

論文

論文
田中, 秀岳 ; 安田, 嘉和 ; 鈴木, 直彦 ; 坂谷, 勝明 ; 安井, 武司 ; 平尾, 政利
出版情報: 精密工学会誌論文集 = Journal of the Japan Society for Precision Engineering. Supplement. Contributed papers.  70  pp.838-842,  2004-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/43214
概要: The study deals with a development of an electric power chuck system for CNC lathe. Today, almost power chuck system for CNC lathes are used with hydraulic system included with hydraulic fluid which causes the environment pollution. Besides, not only the hydraulic pump always wastes energy, but also its heat transfer causes thermal deformation and deteriorates machining accuracy. In the study, in order to remove the hydraulic pump system from CNC lathe, the electric power chuck system which is able to adopt to the general CNC lathe and to have enough capability as general hydraulic power chuck system are developed. The electric power chuck system adopt to alternate general hydraulic pump system. From the experimental result, the developed electric power chuck system is found to have enough abilities. In addition, the electric power chuck system aims to improve machining accuracy by intercepting heat transfer and environmental pollution as well as removing the hydraulic system from machine tools. 続きを見る
2.

論文

論文
平尾, 政利 ; 寺島, 淳雄 ; 朱, 浩允 ; 白瀬, 敬一 ; 安井, 武司
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  64  pp.1067-1071,  1998-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41944
概要: Many researches about cutting temperature have been reported, because of the great influence of a tool face temperature on a tool wear. However, there is few report about cutting heat. The cutting conditions (cutting speed, feed, etc.) and accuracy of temperature measurement in recent cutting are quite different from those in the past. In case of cutting a material like aluminum, for instance, the cutting speed is usually adopted as 1000m/min much higher than that in the past. The behavior of cutting heat (heat into chip, work and tool) in high speed cutting has been investigated applying theory and experiment methods in the present study. The heat generated in the cutting process is distributed to three parts such as main shear plane, rake face and clearance face. In this experiment, the work materials are AISI 1045 steeland Aluminum alloy A5052, and each cutting speed is up to 400m/min and 850m/min. The cutting heat are measured by accurate thermometers at different depths of cut and flank contact lengths. In addition, the heat ratio of chip, work and tool is calculated from theory. Experimental data are similar to theoretical results. Results of this research show that higher the cutting speed, higher the percentage of heat into the chip and lower the percentage of heat in the tool and work. (1) 切込みや逃げ面接触長さを変化させることにより, 切屑, 被削材, 工具への切削熱の流入割合を求めることができた. (2) 切削熱の切屑への流入割合は, 切削速度の上昇とともに増加し, 被削材, 工具へは減少していく. (3) 高速切削になるにつれて, 逃げ面での摩擦による発熱は無視できなくなる. 続きを見る
3.

論文

論文
白瀬, 敬一 ; 平尾, 政利 ; 安井, 武司
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  63  pp.269-273,  1997-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41948
概要: Instantaneous force with static deflection feedback model is applied to predict cutting force and dimensional surface error generation in peripheral milling with irregular tooth pitch end mills. It is demonstrated that the irregular tooth pitch end mill reduces the dimensional surface errors according to the chip regeneration mechanism. Unlike in case of uniform tooth pitch cutters, chip loads on each flute are different in milling with irregular tooth pitch cutters. The excess surface error generated by the flutes which have larger chip loads is removed by the following flutes which have smaller chip load due to the irregular tooth pitch. In order to predict precise cutting force and dimensional surface error for the irregular tooth pitch end mill, the chip regeneration mechanism or the static tool deflection has to be considered to derive the accurate chip loads. Predicted cutting force and dimensional sur face error show good agreement with experimental results. Up to 20% reduction in surface errors is achieved by using the irregular tooth pitch end mills tested. 続きを見る
4.

論文

論文
平尾, 政利 ; 井澤, 正樹 ; 井口, 信明 ; 白瀬, 敬一 ; 安井, 武司
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  64  pp.1335-1339,  1998-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41946
概要: A new experimental method of in-process dressing has been conducted by means of water-jet, as well its application investigated in the present study. While the workpiece is difficult to be ground by the surface grinding machine, the high pressure waterjet is supplied to the grinding wheel as a supplementary method. The principle of this method can be simply described as that the waterjet is a kind of processing technique, which is able to strip the chips on the surface of the grinding wheel without damaging it by adjusting the injection pressure and stand-off distance. The dressing effects are examined according to the surface conditions of the grinding wheel and ground workpiece by a surface roughness and profile measuring device and a microscope. Because of the complexity of the interaction influences between the jet pump pressure and the stand-off distance on the dressing results, in this report at fixed stand-off distance condition the effects of the jet pressure on the grinding wheel of CBN #325 and finished surface of Ti6A14V materials have been clarified. From the results of the experiments, it was found that the dressing life time of the grinding wheel and the roughness of the ground material finished surface have been improved distinctly when the injection pressure is 107.1MPa at stand-off distance 20mm. On the other hand much lower pressure will have no influence on dressing results, and much higher one will damage the CBN wheel. 続きを見る
5.

論文

論文
白瀬, 敬一 ; 平尾, 政利 ; 安井, 武司 ; 河端, 裕 ; 藤村, 善雄
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  60  pp.235-239,  1994-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41947
概要: An NC program simulator has been developed for evaluating productivity in NC lathe turning. Machining information about cutting parameters, tool paths and operating time are retrieved from an NC program by the simulator. These information are very useful in order to evaluate productivity in NC lathe turning. A total of 193 NC programs from 29 manufacturing companies are investigated their productivity by comparing the percentage of jog feeding time during turning operation. The result of the investigation shows that the jog feeding time occupies about 80% of total operation time on an average of 193 examples. The simulation of the revised NC programs using the touch and cut method which eliminates an air-cut travel during jog feeding shows that the operation time of the NC program can be reduced about 6% on an average. The cutting test for estimating tool life proved that the touch and cut method does not reduce the tool lifetime under the experimental cutting condition. 続きを見る
6.

論文

論文
閻, 喜仁 ; 白瀬, 敬一 ; 河端, 裕 ; 平尾, 政利 ; 安井, 武司
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  63  pp.1044-1048,  1997-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41828
概要: The productivity of machining centers is influenced strongly by the quality of NC programs. To investigate the productivity, an NC program simulator has been developed to analyze and evaluate an NC program by decoding its NC codes. With the simulator, even before the actual machining, the tool paths can be displayed and the operational times occupied in the positioning feed motion and cutting feed motion, etc. can be calculated. The effects of the maximum speed and the acceleration of positioning feed on the productivity have been analyzed. Additionally, the influence of feedrate override function to shorten the operational time has been investigated in the conventional and the high speed cutting, respectively. From the results obtained from analyzing three NC programs, it is found that the effectiveness of the override function depends on the relation among the average moving distance, the commanded feedrate and the acceleration of cutting feed. Especially, in the case of the NC program for machining dies or molds, the productivity will be hardly improved using faster feedrate, because the actual feedrate hardly increases as expected due to the tiny moving distances of NC blocks. High speed & high precision function, which is an advanced optional function, is much more effective not only to improve the productivity but also to keep the machining accuracy of high speed cutting. 続きを見る
7.

論文

論文
白瀬, 敬一 ; 佐野, 雅基 ; 平尾, 政利 ; 安井, 武司
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  64.  pp.465-469,  1998-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41949
概要: Chatter vibration for irregular tooth pitch end mill has been simulated using time domain cutting simulation based on the regenerative force and dynamic deflection model. The time domain cutting simulation program assumes that the vibration of end mill can be represented by using a lumped-parameter model with two degrees-of-freedom. Furthermore, it treats realistic nonlinearities accounting for the variation of uncut chip thickness, the changing of cutting force direction. In order to get a stability lobe diagram, the results of many time domain cutting simulations are evaluated by the average acceleration of the tool vibration during one rotation. Predicted stability lobes are compared with the results of cutting experiments, and they show that an irregular tooth pitch end mill can lead to an increase of stability. It is difficult to accomplish the quantitative agreement because of the assumptions in the modeling such as the constraint of tool motion and the treatment of process damping. But, the time domain cutting simulation can give the information to find an optimum cutting condition and a chatter free tool configuration. 続きを見る
8.

論文

論文
閻, 喜仁 ; 白瀬, 敬一 ; 河端, 裕 ; 平尾, 政利 ; 安井, 武司
出版情報: 精密工学会誌 = Journal of the Japan Society for Precision Engineering.  64  pp.768-772,  1998-01-01.  精密工学会 = The Japan Society for Precision Engineering
URL: http://hdl.handle.net/2297/41827
概要: (1) 生産性評価指数として有効送り速度比を導出し, 生産性の良否には, 位置決め制御系の時定数, 工具の1ブロック当たり平均移動距離, 工具移動ベクトルの向きの変化が影響を及ぼすことを示した. (2) 斜面加工で同じ加工精度を目標に, 同 じ半径方向の切込み条件で加工時間を比較すると, 斜面の勾配が0°または90°に近くない限り, スクウェアエンドミルよりもボールエンドミルを用いた方が生産性が良くなる.また, 工具径が大きいほどボールエンドミルがスクウェアエンドミルより効率的である. (3) 典型的な加工形状に対して, 生産性評価指数eを用いて工具経路パターンの違いによる生産性評価を行い, 等高線パターンによるeが, Zigzagパターンによるeよりも大きいことを示した. (4) 加工時間の比較でも, 一般に等高線パターンはZigzagパターンに比べて加工時間が短い.例外は, 波状スプライン面をZigzagパターンで波状に沿って加工する場合であった. (5) 等動力, 中高送りでの加工では, 一般に小径工具の方が加工時間が短い.例外は, 島があるポケット加工の場合であった. The productivity of machining centers is affected not only by the effective feed rates and average tool travel per block studied in the first report, but also by the generated tool paths, especially the variation of moving vectors of the tool. In this paper, first of all, the factor of productivity evaluation is defined extensively to the case of multi-F code, and furthermore expressed as a function of the time constants, feed, average travel per block and the moving vectors of the tool. The expression of the factor shows that the smaller the time constants and the average variation per block of moving vectors, the higher the productivity is, and the longer the average travel per block, the higher the productivity is. Then with feature-based work models, namely, spline plane, slope, boss, island and pocket, being exemplified, the productivity of those NC programs generated by I-DEAS CAM tool is analyzed by the self-developed NC program simulator in two patterns of tool paths, namely the contour line and zigzag. The results show that in most cases, the productivity of the tool path in contour line pattern is higher, and the productivity of machining with a tool of smaller diameter is higher when the cutting power is kept constant. The theoretic and simulative studies on the tool path will contribute to the development of new CAM tools. 続きを見る