A shearer cutting unit with double-speed rollers includes a motor driving unit, a motor driving unit, a gear transmission unit and a roller output unit. The motor driving unit includes a left cutting motor and a right cutting motor which are both arranged in a cutting unit case and connected with the roller output unit in a transmission way through the gear transmission unit. The roller output unit comprises a middle output shaft (3-1), a far-end output shaft, a middle support frame, a middle roller, a far-end support frame and a far-end roller. A cutting roller is separated into two coaxially-rotating parts, and the two rollers can rotate in different speeds.

A shearer cutting unit with double-speed rollers includes a motor driving unit, a motor driving unit, a gear transmission unit and a roller output unit. The motor driving unit includes a left cutting motor and a right cutting motor which are both arranged in a cutting unit case and connected with the roller output unit in a transmission way through the gear transmission unit. The roller output unit comprises a middle output shaft (3-1), a far-end output shaft, a middle support frame, a middle roller, a far-end support frame and a far-end roller. A cutting roller is separated into two coaxially-rotating parts, and the two rollers can rotate in different speeds.

A vertical lifting type drum coal-mining machine without a rocker arm includes a central control box, left and right cutting and lifting reduction gear boxes, left and right guide rail fixing box bodies, left and right traction reduction gear boxes, and left and right traveling gear boxes. The left and right cutting and lifting reduction gear boxes are provided with slideways in fit with lifting guide rails of the left and right guide rail fixing box bodies. Lifting cylinders drive the left and right cutting and lifting reduction gear boxes to make lifting motion. A cutting gear reduction mechanism adopts two-stage fixed-axle gear transmission and two-stage planetary gear transmission, is free from multiple idler pulley groups and has simple transmission chain. The fit between the lifting guide rails and the slideways enables the entire machine to be compact in structure, and the reliability and stability of operation are improved.

A vertical lifting type drum coal-mining machine without a rocker arm includes a central control box, left and right cutting and lifting reduction gear boxes, left and right guide rail fixing box bodies, left and right traction reduction gear boxes, and left and right traveling gear boxes. The left and right cutting and lifting reduction gear boxes are provided with slideways in fit with lifting guide rails of the left and right guide rail fixing box bodies. Lifting cylinders drive the left and right cutting and lifting reduction gear boxes to make lifting motion. A cutting gear reduction mechanism adopts two-stage fixed-axle gear transmission and two-stage planetary gear transmission, is free from multiple idler pulley groups and has simple transmission chain. The fit between the lifting guide rails and the slideways enables the entire machine to be compact in structure, and the reliability and stability of operation are improved.

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 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 cutter head includes a first member, a cutting bit, and a second member. The first member includes a first end and a second end and includes a first mass. The cutting bit is coupled to the first member proximate the second end. The cutting bit includes a cutting edge rotatable about the axis. The second member is rotatable about the axis and includes a second mass eccentrically positioned with respect to the axis. Rotation of the second mass causes the first member and the cutting bit to oscillate.

A cutter head includes a first member, a cutting bit, and a second member. The first member includes a first end and a second end and includes a first mass. The cutting bit is coupled to the first member proximate the second end. The cutting bit includes a cutting edge rotatable about the axis. The second member is rotatable about the axis and includes a second mass eccentrically positioned with respect to the axis. Rotation of the second mass causes the first member and the cutting bit to oscillate.

A cutting assembly is provided for a rock excavation machine having a frame. The cutting assembly includes a boom, a cutting device, and a plurality of fluid actuators. The boom includes a base portion and a movable portion. The base portion is configured to be supported by the frame, and the movable portion is supported for sliding movement relative to the base portion in a direction parallel to a longitudinal axis of the base portion. The boom includes a wrist portion pivotably coupled to the movable portion at a pivot joint. The cutting device is supported on a distal end of the wrist portion. The fluid actuators are coupled between the base portion and the wrist portion. The fluid actuators are operable to move the movable portion and the wrist portion parallel to the longitudinal axis, and are also operable to bias the wrist portion against cutting loads exerted on the cutting device.