The invention relates to a tool for forming a drilled hole (B), comprising a shank that is rotatable or rotates about a tool axis (A), at least one first portion, which is rotatable or rotates about the tool axis (A), for producing and/or widening a drilled hole (B) by chip cutting, and a second portion, which rotates about the tool axis (A), for widening a drilled hole (B) without chip cutting, wherein the second portion is arranged behind the first portion in a direction of advance (V) of the tool. The invention additionally relates to a method for producing a drilled hole (B).

For improving a drill, in particular a spiral drill, comprising a base body extending substantially longitudinally in a direction axial to a drill axis, said base body comprising a drilling portion, wherein a radially inward core region in relation to the drill axis and a radially outer region are provided in the base body in the drilling portion, and the drilling portion comprises a plurality of spiral-shaped recesses in the outer region, and arranged between each two spiral-shaped recesses is a wall part, it is proposed that the drill comprises at least four main cutting edges, in particular exactly four main cutting edge and/or the drill comprises at least three central cutting edge portions.

The drill comprises a base body, which extends in the axial direction along an axis of rotation and rotates about the axis of rotation in a direction of rotation during operation. Into the base body are incorporated flutes and between consecutive flutes is formed a rear surface, which extends, in relation to the direction of rotation, from a leading flute to a trailing flute. On the rear surface in the region of the leading flute, a guide chamfer and a support chamfer spaced apart from it in the direction opposite the direction of rotation are formed, wherein the support chamfer, as radially outermost region, forms a support edge for a merely linear support.

A device for opening a connection to a lined pipe is disclosed. The device has a body that includes a front end and a rear end and being rotatable about a rotation axis. The device also has a drill head that has multiple cutters for puncturing and enlarging a hole in a liner, and multiple side cutters have at least one cutting edge parallel to the rotation axis. A safety ring is disposed on the body between the drill head and the side cutters. The safety ring has a circular periphery extending beyond the drill head and the side cutters in a direction perpendicular to the rotation axis.

This document provides orthopedic and dental devices and methods for their use. For example, novel bone drills and dental drills are described. The bone and dental drills have at least some centers of mass that are offset from the drills' axis of rotation. Accordingly, the bone and dental drills may rotate and cut using a precessional pattern of motion. The design facilitates bone cutting, chip formation and hauling capacity, irrigation and bone harvesting. In some embodiments, the bone chips are collected in a removable apparatus fixed to the distal portion of the drill, and the collected bone chips can be used for bone grafting.

A device for opening a connection to a lined pipe is disclosed. The device has a body that includes a front end and a rear end and being rotatable about a rotation axis. The device also has a drill head that has multiple cutters for puncturing and enlarging a hole in a liner, and multiple side cutters have at least one cutting edge parallel to the rotation axis. A safety ring is disposed on the body between the drill head and the side cutters. The safety ring has a circular periphery extending beyond the drill head and the side cutters in a direction perpendicular to the rotation axis.

A method for producing a twist drill has the following steps. A blank is shaped to form a semi-finished product. The semi-finished product is formed from a core, coaxial with the drill axis, having a radius and a number of webs, arranged on the core, having a height. The semi-finished product has a constant cross section along the drill axis. The webs have a first portion which adjoins the core and in which a width of the web remains constant or decreases in the circumferential direction with increasing radial distance from the drill axis. The webs have a second portion which adjoins the first portion and in which the width of the web increases in the circumferential direction with increasing radial distance from the drill axis. The webs of the semi-finished product are shaped into helical segments using a plurality of rolling tools that annularly enclose the semi-finished product and roll on the webs along the drill axis. The rolling tools have teeth that are inclined with respect to the drill axis. A height of the helical segments is less than the height the webs. Helical segments formed from adjacent webs are in contact with one another in a closing fold. The invention also relates to a twist drill.

A device for opening a connection to a lined pipe is disclosed. The device has a body that includes a front end and a rear end and being rotatable about a rotation axis. The device also has a drill head that has multiple cutters for puncturing and enlarging a hole in a liner, and multiple side cutters have at least one cutting edge parallel to the rotation axis. A safety ring is disposed on the body between the drill head and the side cutters. The safety ring has a circular periphery extending beyond the drill head and the side cutters in a direction perpendicular to the rotation axis.

A device for opening a connection to a lined pipe is disclosed. The device has a body that includes a front end and a rear end and being rotatable about a rotation axis. The device also has a drill head that has multiple cutters for puncturing and enlarging a hole in a liner, and multiple side cutters have at least one cutting edge parallel to the rotation axis. A safety ring is disposed on the body between the drill head and the side cutters. The safety ring has a circular periphery extending beyond the drill head and the side cutters in a direction perpendicular to the rotation axis.

A drill bit for drilling laminates includes at least two main chip flutes separated by corresponding webs. The free end faces of the webs form relief surfaces. At least one secondary flute, which is formed in the periphery of each of the webs divides the web into a main and a secondary web. A main cutting edge is formed by the intersection of a main chip flute and a relief surface on the main web. A secondary cutting edge is formed by the intersection of the secondary flute with a relief surface on the secondary web following the main cutting edge in the direction of operation, the main cutting edges extending to the nominal radius of the drill. The secondary cutting edges terminate at a distance before the nominal radius and axially project from the main cutting edge by an axial overhang at least along their radially outer section.