Abstract: The boring head has a fine movement mechanism for the tool support and a counterweight mounted in the tool body. In order to compensate for imbalance during the adjustment of the cutting tool, the counterweight is moved automatically in the opposite direction by means of a transmission device. The tool support, the counterweight, and the setting screw of the fine movement mechanism can all be simultaneously clamped firmly to the clamping organ.

Abstract: In the tool body (2), a tool support (4) for a cutting-plate holder (6) is mounted capable of fine radial movements. To compensate for imbalance, a balancing device (30) is provided which has at least two weight bodies (20, 21) movable in opposite circumferential directions within the tool body (2) in essentially the same plane. In certain embodiments, each of the two weight bodies (20, 21) forms approximately one-fourth of a circular ring.

Abstract: For the purpose of rigid connection of the cutter holder (9) to the tool carrier (5), the tool carrier (5) has a driving key (11) on its end side, which driving key is inserted into a corresponding transverse groove (13). The driving key (11) has a specified excess size compared to the transverse groove (13), such that when a setscrew (10) is tightened the tool carrier (5) and the cutter holder (9) are elastically deformed. Laterally next to the transverse groove (13) the surface of the cutter holder (9) is supported on the tool carrier (5).

Abstract: A boring head is retained to a connecting shaft by means of a cylindrical fastening spigot, using a retaining screw with a conical end which engages a conical transverse bore in the spigot such that the boring head is tightened by wedging effect against the connecting shaft. The fastening spigot is provided with a cylindrical transverse bore, at an approximate right angle to the conical transverse bore in the spigot, and a longitudinally displaceable drive pin is supported in the cylindrical transverse bore such that the ends penetrate, with slight play, into recesses in the connecting shaft. During the transmission of torque, the drive pin is automatically centered so that the forces developed are evenly distributed between the two ends of the drive pin, so that the device is particularly suitable for the transmission of high torques, whether of a gradually increasing or an impulse type, and is usable either with a clockwise or a counterclockwise movement.

Abstract: The boring tool has an insert upon which one or two boring heads are slidably guided along a swallowtail track. For fixing the boring heads in position, set screws are provided which are adapted to bear against the clamping surfaces of the insert. To preclude radial sliding of the boring heads, even when the set screws are only partially tightened, the clamping surfaces are inclined relative to the longitudinal axis of the insert, and the spacing of the clamping surfaces from the longitudinal axis increases toward the ends of the insert.

Abstract: The boring head has a tool holder in which the cutting tool is retained by a clamping screw. The tool holder is radially adjustable by an adjustment screw having a fine thread. The adjustment screw has a flange and a pressed-on knob which bears an adjustment scale. Between the knob and the flange, the annular portion of an insert is introduced, free of axial play. The annular portion of the insert is connected to the boring head by a set screw.The insert with the annular portion also is provided with a clamping lip which can be pressed against the tool holder by a locking screw. The tool holder with its fine adjustment can be separately mounted and constitutes an easily replaceable unit.

Abstract: The head has a transverse groove in its leading face in which two cutting blade holders with interchangeable cutting blades are clamped by means of a set screw. After loosening of the set screw, the cutting blade holders can be radially and axially adjusted by means of adjusting screws. This enables precise positioning of the cutting blades, to eliminate unequal chip formation, and rough operation due to unequal loading of the blades.

Abstract: A textile floor covering consisting of a textile layer, to the carrier layer of which the pile has been applied, and a bottom of thermoplastic foam, wherein the textile layer is directly connected with a thermoplastic foamed sheeting of polymerizates as a bottom, the polymerizates being selected from a group consisting of ethylene polymerizate, ethylene vinylacetate copolymerizate, and a mixture of ethylene polymerizate and ethylene vinylacetate copolymerizate, the foamed sheeting having a thickness of between 1.5 and 10 mm and a density of 0.10 to 0.40 g/cm.sup.3, preferably from 0.15 to 0.20 g/cm.sup.3.A method for producing a textile floor covering consisting of a textile layer, to the carrier layer of which the pile has been applied, and a bottom of thermoplastic foam, wherein the textile layer is applied directly to a foamed sheeting of polymerizates, as defined above, by means of thermolaminating, welding, sewing or stitch-bonding.