A device for fixing a disk cutter to the cutter head of a shield excavator, wherein a plurality of cylindrical cases (2) are provided on the face plate (1a) of the cutter head (1) rotatably disposed on the front part of the shield proper, bosses (3) are disposed to project face-to-face in each of said cases (2), U-shaped grooves (4a) of retainers (4) provided on both ends of a shaft (7) rotatably supporting the cutter proper (5) are fitted on the bosses (3) so that the cutter proper (5) is turned around the shaft (7) together with the retainer (4); a key block (10) is fixed to the open side of the U-shaped groove (4a) formed on said retainer (4); and the cutter proper (5) is fixed to the case (2) with the boss (3) clamped by the key block (10) and retainer (4). In this way, the cutter proper can be fixed to the cutter proper without forming insertion grooves in the case, the case is small in height, and thus more pieces of cutters can be fixed to the cutter head than before, whereby a fixing device simple in structure, easy to mount, and excellent in strength can be obtained.

The invention relates to a roller cutter comprising rows (41,42) of cutting means, e g hard material inserts, extending along the circumference of the cutter (16-38), said roller cutter (16-38) being reversibly mountable in a saddle (12) of a drill bit (10), the number of rows of the roller cutter being two, the rows (41,42) of cutting means being located on each side of the transverse symmetry plane (45) of the roller cutter, and the distance (B) between the first row (42) and the symmetry plane (45) being longer than the distance (A) between the second row (41) and the symmetry plane (45).

The characterizing feature of the roller cutter (16-38) is that said roller cutter (16-38) is cylindrical. Preferably the distance (B) between the first row (42) and the symmetry plane (45) is essentially three times the distance (A) between the second row (41) and the symmetry plane (45).

Rock working tool for a tunnel boring machine. The tool comprises a shaft (34) with a central hole (35). A tool part (8,9) is rotatably journalled on the shaft. The tool is cooled through the arrangement of channels (40,41,42) in the tool for conducting cooling liquid from a pressure liquid source (22) to the central hole and via the channel (42) which flushes directly on the tool part (8,9).

Rock working tool for a tunnel boring machine. The tool comprises a shaft (34) with a central hole (35). A tool part (8,9) is rotatably journalled on the shaft. The tool is cooled through the arrangement of channels (40,41,42) in the tool for conducting cooling liquid from a pressure liquid source (22) to the central hole and via the channel (42) which flushes directly on the tool part (8,9).

Bei einer Rolle (1) für ein Rollenbohrwerkzeug wird eine Vibrations- oder Schlagbewegung durch eine Unwucht mit Bezug auf die Rollenachse erzielt. Die Grösse der Unwucht und damit die Amplitude der Schlagbewegung ist regelbar durch Einfüllen einer Flüssigkeit von hoher Dichte in einen exzentrisch zur Rollenachse angebrachten Hohlraum (3).

Um bei Bohrköpfen von Tunnelbohrmaschinen, Großlochbohrmaschinen, Schachtbohrmaschinen od.dgl. die Werkzeuge von der Bohrkopfrückseite her ein- und ausbauen zu können, Ist ein Halter mit festen Abstützflächen und mit Durchgangswegen, Durchlässen od.dgl. für die Kopfteile eines Werkzeug-Tragkörpers versehen, in einer solchen Anordnung, daß das Werkzeug in einer zusammengesetzten Bewegung, die eine Drehung oder Schwenkung zumindest eines seiner Teile einbegreift, in den Einbauzustand bewegbar Ist, in dem an den Kopfteilen befindliche Anlageflächen unmittelbar auf den festen Abstützflächen des Halters aufliegen. Die Erfindung ist sowohl für Werkzeuge mit drehbaren Werkzeugelementen, wie Schneidrollen u.dgl., als auch für Werkzeuge mit feststehenden Werkzeugelementen, wie Schrämmeißeln od.dgl., anwendbar.