A tool coupling used for a clamping connection between two coupling parts, in particular between a cutting head and a carrier of a rotary tool, in particular of a drill. The coupling parts comprise clamping sections, which respectively correspond to one another and which can be clamped against each other by turning counter to a predefined direction of rotation about an axis of rotation so that a press fit is produced. In order to produce a high clamping force and at the same time allow for a simple installation via screwing in, each clamping section comprises several successive clamping surfaces whichwith respect to a cross section viewed orthogonally to the axial directionrespectively travel along a circular arc, wherein the diameter increases for clamping surfaces succeeding one another in the direction of rotation.

An accessory tool includes an effector end and a shank coupled to the effector end. The shank includes a tool engagement portion that is configured to be received within a tool and a reduced diameter portion disposed between the tool engagement portion and the effector end. The shank defines a first length, and the reduced diameter portion defines a second length that is 10% to 45% of the first length.

The present invention relates to a tool bit replaceable rotary cutting tool and a rotary cutting method and a tool bit mounting method thereof and belongs to the field of hole machining in the machining industry. At present, a twist drill for drilling is of an integrated structure, and when service life of a tool bit is exhausted, the whole drill is required to be replaced, so that cost is relatively high. For a tool bit replaceable drilling tool, in a drilling process, radial and axial acting forces on a tool bit are relatively strong and thus may cause the conditions of imprecise drilling caused by radial displacement of the tool bit at a joint and the like, a replaceable structure of the tool bit makes the joint of the tool bit of the drilling tool relatively weak and a design of a chip groove makes a substrate of the drilling tool weaker. According to the tool bit replaceable rotary cutting tool of the present invention, a tool bit is detachably connected with a tool bar, and V-shaped positioning surfaces are adopted for a joint of the tool bit and the tool bar, so that a good tool bit positioning and fixation effect is achieved, and the tool bit is unlikely to deviate; a design with different helical angles is adopted for a chip groove, so that strength of the tool bar is strengthened; due to design of cooling guide grooves, a cooling effect is improved; and the tool bit is easy to mount and dismount.

A cutting head rotatable about a first axis, has a cap portion and a rigid mounting protuberance joined thereto. The cap portion has a plurality of cutting portions circumferentially alternating with a plurality of head chip flutes, and a head base surface facing in an axial rearward direction. The mounting protuberance exhibits rotational symmetry about the first axis, extends axially rearwardly from the head base surface, and has a plurality of circumferentially spaced apart convex clamping surfaces. The plurality of cutting portions define a cutting diameter, the plurality of head chip flutes are inscribed by an imaginary first circle having a first diameter, and the plurality of clamping surfaces are circumscribed by an imaginary second circle having a second diameter. The first diameter is greater than the second diameter, and the second diameter is less than forty percent of the cutting diameter.

A cutting tool may include a circular columnar body extending from a first end to a second end along a rotation axis. At least a part of the columnar body may correspond to an insert including a cutting edge at the first end. The insert may include therein a flow path extending from a side of the first end toward a side of the second end. A width of the flow path along a radial direction of the circular columnar body may be smaller than a width of the flow path along a circumferential direction of the circular columnar body in a cross section orthogonal to the rotation axis.

A machining tool, in the area of a tool tip, includes an integrated cooling structure for transporting a coolant. The cooling structure is optionally or in combination designed as a porous structure or at least one cooling channel having a bent reversing segment, so that two channel segments are oriented in opposite directions. The cooling structure is integrated into a base body of a carrier tool. According to a method of the invention, the cooling structure is manufactured by means of a 3D printing method.

The holder has a first surface and a second surface. The head includes a cutting edge portion and a shank portion. The holder is provided with a first hole and a second hole communicating with the first hole, the first hole extending in a third direction inclined by a second angle relative to a second direction extending from the second surface toward the first surface when viewed in a direction parallel to the axis line. The shank portion has a flat surface portion, and is provided inside the second hole. The fastening portion is provided inside the first hole, and is in contact with the flat surface portion. In a plane perpendicular to the axis line, a third angle between the second direction and a fourth direction perpendicular to the flat surface portion is larger than the second angle. The third angle is less than 90.

A drill bit includes a tool body having a main body in the form of a cylinder. A chip removing structure is provided on the main body. The tool body has a distal end provided with a clamping slot and a cutter inlaid in the clamping slot. The cutter has at least two blade portions arranged circumferentially on the distal end of the tool body and extending radially relative to the tool body. Each of the blade portions has a front side along the drill bit's rotating direction and a back side against the rotating direction. The clamping slot covers the back side of one blade portion by an area larger than that used to cover the front side of the same blade portion.

A rotary tool, comprising: a tool main body comprising a clamping section and a tool head; an exchangeable first cutting insert having at least one first cutting region having a first cutting edge, wherein the first cutting insert can be inserted into an insert groove of the tool main body from the front side of the tool head and can be fastened therein in a rotationally fixed manner; and an exchangeable second cutting insert fastened to the tool head and offset toward the clamping section in the axial direction of the rotary tool relative to the first cutting insert and which has an insert main body and at least one second cutting region having at least one second cutting edge. A fastening means for the second cutting insert is arranged in the insert groove of the first cutting insert. Also, a cutting insert set and a tool main-body set.

A cutting tool according to one aspect of the present disclosure includes an attaching portion, a cutting portion having a core portion and a surface portion, and a joint portion. The attaching portion includes a hard component and a hard material. The hard component is at least one selected from the group consisting of TiC, TiCN, W, WC, Al.sub.2O.sub.3, and a combination of at least one of CBN and diamond and at least one of W and WC. The hard material includes one or two or more types of iron group elements, and has a Young's modulus of not more than 350 GPa. The core portion includes a cemented carbide material. The surface portion includes PCD or CBN. The cutting portion has a chamfer portion. The surface portion includes a groove, a flank face, and a cutting edge. The cutting edge extends toward the attaching portion.