公开(公告)号：US20220241873A1

公开(公告)日：2022-08-04

申请号：US17619207

申请日：2020-06-10

Applicant: BIC TOOL CO., LTD.

Inventor： Koichi Arai ,  Giichi Arai ,  Katsuyo Kimura ,  Satoshi Teshima

IPC: B23B51/02

Abstract: The drill of the invention has: two cutting edges, each having a main cutting edge and a thinned cutting edge, wherein two relief surfaces formed symmetrically around rotation axis, first and second margin portions are formed, the first margin portions have a forward-end small-diameter portion with diameter smaller than the drill diameter, that is formed from the side of the drill forward-end toward the drill rearward-end, the second margin portions have a second forward-end small-diameter portion with diameter smaller than the first forward-end small-diameter portion, that is formed from the side of the drill forward-end toward the side of the drill rearward-end, the first forward-end small-diameter portion and the second forward-end small-diameter portion have inclination portions, the diameters of which gradually increase from the side of the drill forward-end toward the side of the drill rearward-end, and the inclination portions of the first forward-end small-diameter portion have relief surfaces.

公开(公告)号：US20230054778A1

公开(公告)日：2023-02-23

申请号：US17619229

申请日：2020-12-26

Applicant: BIC TOOL CO., LTD.

Inventor： Koichi Arai ,  Giichi Arai ,  Katsuyo Kimura ,  Satoshi Teshima

IPC: A61B17/16

Abstract: To design a novel tip end shape that performs most of the drilling process so as to prevent chips from entering the gap between the hollow drill bit and the small-diameter drill bit fitted into the hollow portion of the hollow drill bit as well as to provide a structure of the outer periphery so as to allow chips to be discharged toward the outer periphery and prevent them from entering the gap portion.
A hollow drill bit for medical use of the present invention is characterized in comprising a hollow portion that penetrates the axial center in the axial direction from the tip end to the distal end; and four cutting edges at the tip end section, wherein arc-shaped outer peripheral grooves are helically formed in the cylinder-shaped outer peripheral portion.

公开(公告)号：US11364555B2

公开(公告)日：2022-06-21

申请号：US16369223

申请日：2019-03-29

Applicant: Bic Tool Co., Ltd

Inventor： Koichi Arai ,  Giichi Arai ,  Katsuyo Kimura ,  Satoshi Teshima

IPC: B23B51/02

Abstract: Provided herein is a drill having less possibility of cracks in an inner periphery of a drilled workpiece and deformation of a workpiece upon penetrating with a drill, as well as delamination.
A drill according to the present invention comprises two cutting blades which are formed symmetrical about an axis of rotation, wherein each of the cutting blades has a main cutting blade formed from a drill tip toward a peripheral side of the drill to become a shape with curves, a thinning cutting blade in a shape with curves formed in closer to the drill tip than the main cutting blade, and an U-shaped cutting blade in a shape with curves formed in closer to the periphery of the drill than the thinning cutting blade.

公开(公告)号：US20190308254A1

公开(公告)日：2019-10-10

申请号：US16369223

申请日：2019-03-29

Applicant: Bic Tool Co., Ltd

Inventor： Koichi Arai ,  Giichi Arai ,  Katsuyo Kimura ,  Satoshi Teshima

IPC: B23B51/02

Abstract: Provided herein is a drill having less possibility of cracks in an inner periphery of a drilled workpiece and deformation of a workpiece upon penetrating with a drill, as well as delamination.A drill according to the present invention comprises two cutting blades which are formed symmetrical about an axis of rotation, wherein each of the cutting blades has a main cutting blade formed from a drill tip toward a peripheral side of the drill to become a shape with curves, a thinning cutting blade in a shape with curves formed in closer to the drill tip than the main cutting blade, and an U-shaped cutting blade in a shape with curves formed in closer to the periphery of the drill than the thinning cutting blade.