Abstract: A drill head manufacturing method calls for a cutting tip to be CVD coated, brazed to a distal end of a drill head, polished and then PVD coated. The process effectively utilizes features of a CVD coating, which renders a tool service life longer and enables a drill head more suitable for high-speed cutting to be manufactured. A cutting tip having been CVD coated with a hard material is brazed at a brazing temperature to a predetermined portion at a distal end side of a head main body. An outer diameter portion OD of the brazed tip about a rotation axis of the head main body is polished. Then, the cutting tip and the head main body are PVD coated with a hard material at a second temperature lower than the brazing temperature.

Abstract: A three-way indexable throwaway tip for deep-hole drilling can be used as a center cutting blade body for a drill head in either whole cutting type or uncut core break-off type applications. The throwaway tip for deep-hole drilling is of a thick plate body having a three-fold symmetry with three cutting sections that are rotationally spaced apart at a central angle of 120 degrees. When mounted on a drill head, one cutting section of the throwaway tip faces a drilling direction. The forward facing blade edge of that cutting section includes an inner blade edge shorter in blade length and an outer blade edge longer in blade length forming an apex. The outer blade edge is composed of two consecutive blade edge portions of a peak-side outer blade edge portion having a smaller outer blade edge angle and a corner-side outer blade edge portion having a larger outer blade edge angle.

Abstract: Provided is a drill head for deep-hole drilling which does not generate such a disc that clogs a cutting chip discharge port when a head main body of the drill head penetrates a work material. The drill head is mounted with a central cutting blade tip 6 at the head center portion so as for a blade edge 6a thereof to be inclined downward toward the head center portion, a circumferential cutting blade tip 7 at a circumferential portion so as for a blade edge 7a thereof to be inclined upward toward the head center portion, and an intermediate cutting blade tip 8 therebetween so as for a blade edge 8a thereof to be inclined upwardly and inwardly toward the head center portion, while the cutting blade tips face a cutting chip discharge port 4 or 5. The drill head includes a head main body 2 having an interior hollow portion 3 serving as a cutting chip discharge passage which communicates with the discharge ports 4 and 5.

Abstract: Provided is a drill head for deep-hole drilling in which a cutting blade tip is mounted to face a cutting chip discharge port opened at a head distal end surface and a hollow inside is made into a cutting chip discharge passage communicating with the cutting chip discharge port, wherein high cutting efficiency based on good cutting chip dischargeability can be achieved and the cutting blade itself is also easily processed in terms of form.

Abstract: A gun drill having excellent cutting efficiency, having high deep-hole drilling efficiency, and having a prolonged blade service life has a cutter head having a coolant discharge port communicating with a coolant supplying path at the distal end face at the distal end of a hollow shank portion having a cutting chip discharge groove, whose section along the lengthwise direction is V-shaped, on the outer surface and having the interior thereof made into a coolant supplying path, wherein a blade portion of the cutter head is made of cemented carbide alloy, and at the same time, the guide pads and that are brought into sliding contact with the inner circumference of a cutting bore are composed of a dissimilar material having higher hardness than the cemented carbide alloy.

Abstract: A gun drill has a cutting blade which attains high cutting efficiency without requiring exact positional accuracy at the time of brazing an associated cutting blade tip onto a cutting head. Thus, the cutting head can be manufactured easily and the cutting blade itself is also easily processed. The cutting blade is configured such that an inner end of a blade edge is spaced apart from a head central axis to form a non-cutting zone in the vicinity of the shaft center, a cutting blade side face at the inner end side constitutes an inclined surface which is inclined from the inner end to the head central axis side, and a uncut core of a work material generated in the non-cutting zone is broken off by press-contact of the inclined cutting blade side face during drilling operations.

Abstract: A gun drill is capable of supplying a coolant sufficiently to a cutting region even when a cutting blade or a guide pad is of a brazed type, or when an opening angle of a cutting chip discharge groove is large or when a tool diameter is small and of achieving high cutting efficiency by discharging cutting chips efficiently from the cutting region. The gun drill includes coolant supply passages inside a tool shank and inside a cutting head. A lengthwise direction linear cutting chip discharge groove on an outer circumferential surface extends from a proximal side of the tool shank to a cutting head distal end. The cutting head is formed with a coolant lead-out groove extending from a head-lengthwise direction intermediate portion to the head distal end, at an outer circumferential surface portion at a back side relative to the cutting chip discharge groove. A coolant lead-out port communicating with a coolant supply passage is open at a proximal end side of the coolant lead-out groove.

Abstract: A deep hole cutting apparatus has a guide pad brazed to a cutting head section. With the deep hole cutting apparatus, high machining accuracy can be obtained in a stable cutting status and the service life of the guide pad is lengthened. A guide pad (5) brazed to a cutting head section (10a) is diagonally arranged so that the leading end side of the tool is closer to the front side in a tool rotating direction (y) compared with the rear end side of the tool.

Abstract: A machine reamer has a plurality of slender blades erected on the outer peripheral part of a reamer head body. Each blade of a pair of blades facing each other in a radial direction are different in material kind from each other. One of the blades treated as a pair is made of super-hard alloy and the other blade is made of one kind of material selected from the group of sintered ceramic, cermet, and microcrystalline diamond sintered material.

Abstract: The invention provides a drill head for deep hole machining capable of raising circularity and straightness of a hole and improving precision of hole machining. In the drill head for deep hole machining constituted by fixing a cutting blade to a tip surface of a head body and fixing guide pads to a periphery of a tip of the head body, the length Lm of a margin, which is formed at a tip side of a periphery of the cutting blade in a drill rotating direction, in an axis direction is made substantially the same as the length Lp of the guide pads in the axis direction, and a top end and rear end of the margin are substantially aligned with a top end and rear end of the guide pads, respectively, in a circumference direction.