| 摘要 |
PURPOSE:To prevent the generation of burrs and milling marks by providing a plurality of concave grooves axially on the outer peripheral surface of an end mill having outer peripheral blades and end face blades, and providing left hand and right hand spiral outer peripheral edges on the outer peripheral surface between the concave grooves. CONSTITUTION:This end mill is provided on the front end of shaft body 1 with a end face end 2, and a shaft body 1 is provided on the outer peripheral surface with a plurality of concave grooves 3 extending axially. Left and right hand spiral outer peripheral edges 4a, 4b are provided between the concave grooves 3. Thus, during one revolution of the end mill, the side surface and others of groove 3 are cut alternatively in different directions by said edges 4a, 4b. Burrs and milling marks produced by cutting with one of said edge 4a or 4b are removed by the other of said edge 4b or 4a. Thus, high quality cutting with extremely few burrs and milling marks can be carried out by such alternative cutting operations. |
