A cutting assembly for a rock excavation machine having a frame includes a boom and a cutting device supported on the boom. The boom includes a first portion and a second portion, the first portion supported for pivotable movement relative to the frame. In some embodiments, the first portion includes a first structure extending along a longitudinal base axis and a second structure moveable relative to the first portion in a direction parallel to the longitudinal base axis, and at least one bearing supports the second portion for movement relative to the first portion. In some embodiments, the second portion is pivotably coupled to the first portion by a universal joint, and a suspension system including a plurality of biasing members may be coupled between the first portion and the second portion.

A cutting assembly for a rock excavation machine having a frame includes a boom and a cutting device supported on the boom. The boom includes a first portion and a second portion, the first portion supported for pivotable movement relative to the frame. In some embodiments, the first portion includes a first structure extending along a longitudinal base axis and a second structure moveable relative to the first portion in a direction parallel to the longitudinal base axis, and at least one bearing supports the second portion for movement relative to the first portion. In some embodiments, the second portion is pivotably coupled to the first portion by a universal joint, and a suspension system including a plurality of biasing members may be coupled between the first portion and the second portion.

A cutting device for engaging a rock face includes a disc body supported for rotation about an axis of rotation, and a plurality of peripheral portions removably secured to the disc body. Each of the peripheral portions including a plurality of cutting bits positioned on a peripheral edge. The peripheral edge of each peripheral portion is aligned with the peripheral edges of adjacent peripheral portions.

A cutting device for engaging a rock face includes a disc body supported for rotation about an axis of rotation, and a plurality of peripheral portions removably secured to the disc body. Each of the peripheral portions including a plurality of cutting bits positioned on a peripheral edge. The peripheral edge of each peripheral portion is aligned with the peripheral edges of adjacent peripheral portions.

A cutting apparatus suitable for creating tunnels and subterranean roadways includes independently pivoting supports that each carry a respective independently pivoting arm and a rotatable cutting head. Each cutting head via the supports and arms, is configured to slew laterally outward in a sideways direction and to pivot in a vertical upward and downward direction. The supports and arms are mounted on a linear moving sled carried by a main frame.

A cutting apparatus suitable for creating tunnels and subterranean roadways includes independently pivoting supports that each carry a respective independently pivoting arm and a rotatable cutting head. Each cutting head via the supports and arms, is configured to slew laterally outward in a sideways direction and to pivot in a vertical upward and downward direction. The supports and arms are mounted on a linear moving sled carried by a main frame.

A machine for excavating rock includes a frame, a cutting device, and a boom. The cutting device includes a cutting disc having a cutting edge, and the cutting disc is rotatable about a cutting device axis. The boom supports the cutting device and includes a first end, a second end, and a boom axis substantially parallel to the cutting device axis. The boom further includes a first portion and a second portion. The first portion is coupled to the frame for rotation about a first pivot axis between a raised position and a lowered position. The second portion is coupled to the cutting device, and the second portion is pivotable about a second pivot axis between a raised position and a lowered position.

A machine for excavating rock includes a frame, a cutting device, and a boom. The cutting device includes a cutting disc having a cutting edge, and the cutting disc is rotatable about a cutting device axis. The boom supports the cutting device and includes a first end, a second end, and a boom axis substantially parallel to the cutting device axis. The boom further includes a first portion and a second portion. The first portion is coupled to the frame for rotation about a first pivot axis between a raised position and a lowered position. The second portion is coupled to the cutting device, and the second portion is pivotable about a second pivot axis between a raised position and a lowered position.

A cutter for a cutting unit used in cutting apparatus suitable for creating tunnels or subterranean roadways. The cutter includes a disc body having an underside, an upper side arranged substantially opposite to the underside, and a radially peripheral part. A plurality of buttons for abrading rock are mounted in the radially peripheral part of the disc body and protrude outwardly therefrom to engage rock during an undercutting operation, wherein at least some of the buttons have a cutting part having a dome-shaped cutting surface.

A cutting apparatus includes a support structure and first and second cutting assemblies. Each cutting assembly includes a rotatable cutting head and a mounting assembly for movably attaching the cutting head to the support structure. The cutting head is movable about a first pivot axis of the mounting assembly in a sideways direction relative to the support structure, and about a second pivot axis in an upwards-downwards direction. Each cutting head includes a plurality of cutting units, which each have a rotatable shaft and a cutter mounted thereon. The cutter includes a disc body and a plurality of buttons mounted in a radially peripheral portion of the disc body. At least some of the buttons have a central longitudinal axis that subtends an angle to a reference axis, which extends perpendicularly outwards from an axis of the shaft, the angle being to 20 and to 34.