Development of Chisel-less New Point Drills and Study on High Efficiency Drilling System

无凿子新型尖头钻头研制及高效钻孔系统研究

• 批准号: 61460095
• 负责人: SAKUMA Keizo
• 金额: $ 2.11万
• 依托单位: Fukuoka Insitute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460095/
• 关键词: Cutting; Design; Chisel-less; New point drill; Twith drill; Measurement; Torque; スラスト; ドリル; チゼルレスドリル; 穴加工; 深穴加工; 加工能率; 加工精度

In drilling with conventional twist drills, cutting thrust is so large that many roubles occur in workshop. For aims to improve the hole-making process, new type of drill point, called "Chisel-less drill point" is developed. Design, point grinding method and cutting performance on this tool are investigated, using theoretical analysis and cutting experiments.1. In this drill point, dual apex-point type of cutting lip is constructed by regrinding the conventional drill point. So, "chisel edge" is not formed on center portion of tool. The result of drilling tests by new tool has shown a large decrease o fthrust force. Its magnitude is 1/2 - 1/3 compared with the force of conventional point drill.2. Optimum value is observed in apex distance. The ratio of 1mm to 12.5 diameter shows good results. Larger the value of apex distance, run-out of the tool increases. It increase the hole oversize as well as instabillity in start of cut. New design of point is further investigated to avoid this phenomenon, which is verified by cutting tests.3. Point grinding method is introduced by geometrical analysis of tool. This tool shape is easily ground by the periphery and side face of cup-type wheel, using a universal tool grinder. Special tool attachment, which has 3 regulating axis, was produced.4. The causes of concentration of excessive large thrust force on chisel edge are analyzed on conventional drills. This extra force is perfectly avoidable on "Chisel- less point drill". Theoretical analysis of cutting forces verified that calculated values agreed well with experimental values on thrust force of new tool.

普通麻花钻钻削时，切削推力大，给车间带来了很大的困难。为了改善钻削加工工艺，研制了一种新型钻尖--无凿钻尖。通过理论分析和切削试验，对该刀具的设计、点磨削方法和切削性能进行了研究.该钻尖通过对常规钻尖进行二次磨削，构造出双尖型切削刃。因此，“横刃”不会形成在工具的中心部分。钻削试验结果表明，新型钻具的钻削推力有较大幅度的下降。它的大小是传统点钻的1/2 - 1/3。观察到顶点距离的最佳值。直径比为1 mm/12.5时，效果较好。齿顶距越大，刀具跳动越大。增加了开孔的尺寸和开孔的不稳定性。进一步研究了新的刀尖设计，避免了这种现象，并通过切削试验进行了验证.通过对刀具的几何分析，介绍了点磨削法。这种工具形状很容易通过杯形砂轮的周边和侧面，使用万能工具磨床磨削。制作了具有3个调节轴的专用工具附件.分析了常规钻头横刃推力集中过大的原因。这种额外的力量是完全可以避免的“无凿点钻”。通过对切削力的理论分析，验证了新刀具推力的计算值与实验值吻合较好。

项目成果

榊原昭二: 日本機械学会北陸信越支部北陸地方(富山)講演会講演概要集. 877-2. 50-52 (1987)

Shoji Sakakibara：日本机械工程师学会北陆地区（富山）演讲会摘要 877-2（1987）。

田口紘一: 精密工学会九州支部福岡地方講演会講演論文集. 5-6 (1986)

Koichi Taguchi：日本精密工程学会九州分会的会议记录，福冈地区会议 5-6 (1986)。

Taguchi,Koichi: "Development of Chisel-less New point Drills (Shape Design and) Grinding Method)" Proc. of JSPE, Tokyo, (1986,March). 917-918 (1986)

田口浩一：“无凿子新型钻头的开发（形状设计和）磨削方法）”Proc。

Taguchi,Koichi: "Cutting Performance of Chisel-less New Point Drills" Proc. Of JSME, Kyushu, (1986,March). 36-37 (1987)

田口浩一：“无凿子新点钻头的切削性能”Proc。

Taguchi,Koichi: "Cutting Performance of Four-facet Drills" Proc. of JSPE, Fukuoka, (19868November). 5-6 (1986)

田口浩一：“四面钻的切削性能”Proc。