Abstract: A boring head for reaming a pre-drilled hole in raise boring or for similar earth cutting operations comprising a plurality of roller cutters (13, 14), each of which being rotatably journalled over a bearing system. The bearing system comprises a split roller bearing (60) having axially spaced rollers (62, 63) which are separated by a loose guide ring (69).

Abstract: A tool mounting for a planing machine in which the cutting tools are exposed to high tangential forces. The tool is held on a rotary drum by a wedging action so as to be more readily replaced. The tool may comprise separate adapter and cutter bit components, or in the form of a one-piece member. The tool adapter includes a projection extending from an end opposite from the cutting tool. The projection includes a first contact surface and the mounting includes a second contact surface located outwardly from the first contact surface which first and second contact surfaces converge toward one another. In this way, the first and second contact surfaces cooperate with corresponding surfaces on the cutting head to wedgingly secure the adapter thereto.

Abstract: A bore head for reaming a pre-drilled hole in raise boring or for similar earth cutting operations comprising at least two sets of roller cutters. The roller cutters in the same set of cutters have the same number of rows of cutting means. The roller cutters are mounted in pairs on each side of the rotational axis of the bore head. During rotation of the bore head the cutting means move along concentric circles. In order to change the distance between two consecutive circles a roller cutter in one of the pairs of cutters is replaced by a roller cutter of the other set of cutters.

Abstract: A reamer bit for raise boring in rock, of the type comprising a body on which a number of rolling cutters with cutting inserts are rotatably mounted for contact with and disintegration of the rock, and a detachable stem mounted in a central bore on the body and adapted to be received in a pilot hole drilled in advance in the rock. The stem has two cylindrical portions, an upper one of which having a smaller diameter than a lower one thereof. The bore in the body has corresponding upper and lower cylindrical portions surrounding the stem. The upper cylindrical portions of the body and the stem define upper stem restraining surface means. The lower cylindrical portions of the body and the stem define lower stem restraining surface means. The stem at its lower portion is provided with a flange abutting the body from below and supporting it axially. The upper and lower restraining surface means together comprise a substantial axial portion of the part of the stem that is surrounded by the bore.

Abstract: The invention relates to an apparatus for connecting a male part to a female part, of the type wherein the female part comprises a hole and a locking pin extending eccentrically across the hole. The male part comprises a cylindrical shank, the shank including a groove for engagement with the locking pin. The periphery of the shank includes a beveled portion of sufficient depth to allow a lower portion of the shank to pass the locking pin during insertion of the shank into the hole. The groove is disposed in such lower portion of the shank and is arranged to receive the locking pin in response to rotation of the shaft to prevent withdrawal of the shank.