Abstract: An operator's compartment for a mobile machine, such as a machine used in underground mining operations, is pivotally connected to the machine frame for positioning at a preselected elevation above the ground or in contact with the ground to follow the contour of the ground in a "free floating" condition. The first overhead canopy is supported above the operator's compartment at a fixed elevation. Positioned beneath the first overhead canopy is an operator's seat securely positioned on the platform to provide an operator's station from which the machine is operated. Positioned in underlying relation with the first overhead canopy is a second overhead canopy that extends forwardly from the operator's station. The first and second canopies provide for complete overhead protection of an operator.

Abstract: A self-propelled boring type mining machine includes a mobile frame and a pair of spaced apart drive shafts that extend forwardly from a gear box mounted on the frame. A pair of rotary boring heads are nonrotatably connected to the pair of drive shafts and are operable to cut a pair of bores in a mine face to dislodge the mine material. Cusps formed at the mine roof and floor are dislodged by upper and lower cutter chains that are carried by upper and lower cutter bars movably positioned on the front end of the frame. Cutter bar extensions are movably positioned on both sides of the upper and lower cutter bars by control links pivotally connected to the extensions and the mobile frame. The upper and lower cutter bars are vertically extended and retracted by piston cylinder assemblies. Movement of the cutter bars is transmitted to the cutter bar extensions which are guided on the respective cutter bars along combined horizontal and vertical paths.

Abstract: A rotor arm cutting assembly includes a plurality of cutter arm members extending radially outwardly from a hub portion which is adapted for nonrotatable connection to a drive shaft extending from the front of a mining machine. Each cutter arm member includes a front face for supporting cutter bits operable to dislodge solid material from a mine face upon rotation of the drive shaft. A slot extends longitudinally outwardly from the hub portion to the end of each cutter arm member on the front face. A cutter arm extension is positioned for longitudinal movement in the slot. Complimentary guide members and guide ways associated with the extension portion and the cutter arm member maintain the extension portion movable in a longitudinal direction in the slot. The extension portion is extended and retracted relative to the cutter arm member by operation of a fluid actuated cylinder positioned for convenient servicing within a recess in the back of the cutter arm member.