Abstract: A mining machine includes a frame, a boom supported for pivoting movement relative to the frame, and a cutter head pivotably coupled to the boom. The cutter head includes a housing, a cutter shaft coupled to the housing, a cutting disc, and an excitation mechanism. A second portion of the cutter shaft extends parallel to a cutter axis. The cutting disc is coupled to the second portion of the cutter shaft and is supported for free rotation relative to the cutter shaft about the cutter axis. The cutting disc includes a plurality of cutting bits defining a cutting edge. The excitation mechanism includes an exciter shaft and a mass eccentrically coupled to the cutter shaft. The excitation mechanism is coupled to the first portion of the cutter shaft. Rotation of the exciter shaft induces oscillating movement of the second portion of the cutter shaft and the cutting disc.

Abstract: In some aspects, a conveyor chain includes a first link, a second link, and a coupler link coupled between the first link and the second link. The first link includes a first portion and a second portion, the second portion oriented parallel to and laterally spaced apart from the first portion. The first portion includes a first sprocket-engaging pin protruding laterally, and the second portion includes a second sprocket-engaging pin protruding laterally. The second link includes a first portion and a second portion. The first portion includes a first sprocket-engaging portion protruding laterally, and the second portion includes a second sprocket-engaging portion protruding laterally. A flight bar is positioned adjacent an end of the first sprocket-engaging portion of the first link.

Abstract: A wheel unit includes a suspension housing having a pin defining a steering axis, a transmission housing pivotable about the steering axis, a wheel rim rotatable about a rotational axis and configured to pivot about the steering axis, and a coupled compound planetary transmission drivingly engaged with the wheel rim. The coupled compound planetary transmission includes an input drive shaft, a sun gear rotatable about the rotational axis, a constant velocity joint coupled between the input drive shaft and the sun gear, a first ring gear fixed relative to the transmission housing, a first planet gear enmeshed with the sun gear and the first ring gear, a second ring gear fixed relative to the wheel rim for co-rotation about the rotational axis, a second planet gear enmeshed with the second ring gear, and a shaft coupling the first planet gear and the second planet gear for co-rotation.

Abstract: A linkage for moving material from a first end of a conveyor toward a second end of the conveyor includes a first link and a second link. The first link includes a first side edge and a first indicator. The second link includes a second side edge and a second indicator. The second link is coupled to the first link such that the first side edge of the first link overlaps with the second side edge of the second link. Elongation of the first link in the direction of movement causes the first indicator to move relative to the second indicator, and a position of the first indicator relative to the second indicator provides an indication of a wear condition of the first link. In some aspects, a first surface and/or a second surface of one of the links includes a wear indicator representing a surface wear condition.

Abstract: A method of monitoring a longwall shearing mining machine in a longwall mining system, wherein the shearing mining machine includes a shearer having a first cutter drum and a second cutter drum, includes receiving, by a processor, shearer position data over a shear cycle. The horizon profile data includes information regarding at least one of the group comprising of a position and angle of the shearer, a position of the first cutter drum, and a position of the second cutter drum. The method also includes analyzing the shearer position data, by the processor, to determine whether a position failure occurred during the shear cycle based on whether the computed horizon profile data was within normal operational parameters during the shear cycle, and generating an alert upon determining that the position failure occurred during the shear cycle.

Abstract: A fluid spray for an underground roof support includes a first housing portion, a spray outlet, a second housing portion formed integrally with the first housing portion, and a service port. The first housing portion includes an elongated shaft having a first end, a second end, and a first fluid passage extending between the first end and the second end. The spray outlet is positioned adjacent the second end of the shaft. The second housing portion is positioned adjacent the first end of the shaft. The second housing portion includes at least one port and a second fluid passage between the at least one port and the first fluid passage. The service port is aligned with the first fluid passage, and the service port is selectively opened to provide access to the first fluid passage from the first end of the first housing portion.

Abstract: Systems and methods are described for monitoring a condition of a mine roof using a longwall mining system. A plurality of powered roof supports is controlled to apply an adjustable support pressure on a mine roof. A condition of the mine roof is monitored based on the adjustable support pressure applied to the roof by a respective actuator of each powered roof support. In some implementations, the condition of the mine roof is monitored by generating and analyzing a graphical pressure map based on the adjustable support pressure applied by each powered roof support and a relative position of a shearer moving across the mine face. In some implementations, roof collapse events are detected based on temporally similar changes in the adjustable support pressure applied by multiple adjacent powered roof supports as indicated by the graphical pressure map.

Abstract: A mining machine including a frame, a cutting head moveably coupled to the frame and pivotable about an axis that is substantially perpendicular to a first mine surface, and a first actuator for stabilizing the frame relative to the first mine surface. The first actuator is coupled to the frame and includes a first end extendable in a first direction to engage the first mine surface. The extension of the first actuator is automatically controlled based on measurements of at least one indicator of the force between the first actuator and the first mine surface.

Abstract: A cutting device for a cutting head includes a disc, a plurality of cutting elements secured to the disc, and a plurality of wear elements secured to the disc. The disc rotates about an axis of rotation, and the disc includes a peripheral edge. The cutting elements are spaced apart from one another along the peripheral edge of the disc. The wear elements are spaced apart from one another and from the cutting elements.

Abstract: A conveyor support includes a frame, a roller, and a retainer. The frame includes a support arm. The roller includes a shaft and a shell supported for rotation relative to the shaft, and the shaft includes an end. The retainer releasably secures the end of the shaft relative to the support arm. The retainer includes a first portion engaging a first side of the support arm and a second portion engaging a second side of the support arm. The second portion is biased toward the first portion to exert a compressive force on the support arm. At least one of the first portion and the second portion engages the shaft of the roller.

Abstract: A method is provided for removing slack in a chain conveyor driven between a first sprocket and a second sprocket, the first sprocket and the second sprocket rotating in a first direction. The method includes: locking the second sprocket to prevent rotation of the second sprocket in a second direction opposite the first direction; operating the first sprocket in the second direction to position a slack portion between the first sprocket and the second sprocket; and removing at least one chain link from the slack portion.

Abstract: A mining machine includes a chassis, a cutting assembly coupled to the chassis, and a spray arm coupled to the chassis and positioned proximate the cutting assembly. The chassis includes a first end, a second end, and a chassis axis extending between the first end and the second end. The chassis is movable in a direction parallel to the chassis axis. The cutting assembly includes an arm and a rotatable cutting drum having a plurality of cutting elements. The spray arm includes a first portion, a second portion pivotably coupled to the first portion, and at least one spray nozzle for emitting a fluid spray in a region adjacent the cutting assembly. The first portion is coupled to the chassis and extends away from the chassis along a spray arm axis. The second portion is pivotable relative to the first portion about a wrist axis.

Abstract: A mining machine including a chassis, an actuator, a cutter drum supported by the chassis, the cutter drum driven by the actuator, a cutter bit coupled to the cutter drum, and a controller. The controller includes a processor and memory and is configured to measure a characteristic of the actuator, determine the cutter bit is worn based on the measured characteristic of the actuator, and output a signal when the cutter bit is determined to be worn.

Abstract: A system for guiding movement of a chassis of a mining machine along a rack includes a shoe and a fluid line for receiving fluid from a fluid source. The shoe is configured to be coupled to the chassis and slidably engage the rack. The shoe is configured to extend at least partially around the rack. The shoe includes a first end, a second end, an inner surface, and an outer surface. At least a portion of the inner surface is configured to be positioned adjacent the rack. The fluid line includes an outlet positioned proximate the shoe for dispensing the fluid at an interface between the shoe and the rack.

Abstract: A conveyor assembly for moving material includes a plurality of chains each defining a longitudinal axis, and a plurality of flights coupled to the at least two chains and configured to contact and move the material in a direction parallel to the longitudinal axes. Each of the plurality of flights extends along a central axis oriented oblique with respect to the longitudinal axes. Each flight includes a first portion offset from a second portion in a direction parallel to the longitudinal axes.

Abstract: Systems and methods for monitoring extraction height and volume of material extracted for a mining machine. The method includes operating the machine using a shearing motion at a plurality of cut locations. The method includes receiving boom height data and power consumption data. The method includes determining a cut start time, based on a conveyor motor start time, and a conveyor motor stop time. The method includes determining whether a relocation has occurred. The method includes, when the relocation has occurred: determining a cut end time based on conveyor motor stop time and the relocation; and storing, in a memory, the cut start and end time, and the boom height and power consumption data. The method includes adjusting the operation of the mining machine based on the cut start and end time, and the boom height and power consumption data for at least one of the cut locations.

Abstract: A method of controlling a longwall mining system, the longwall mining system including a longwall shearer, a conveyor, and a plurality of roof supports, such that the method includes creating, by a controller, a load profile of the conveyor representing a distribution of mineral along a length of the conveyor, calculating, by the controller, a desired change in the load profile based on the load profile of the conveyor, and controlling, by the controller, the longwall mining system to adjust the distribution of mineral on the conveyor based on the desired change in load profile.

Abstract: A monitoring device and method for monitoring a longwall mining system having a roof support, the roof support including a pressure sensor to determine pressure levels of the roof support during a monitoring cycle. Pressure information is obtained for the roof support. An electronic processor then determines whether the pressure information is indicative of a first type of pressure failure of the roof support and whether the pressure information is indicative of a second type of pressure failure of the roof support. An alert is generated in response to determining that the pressure information is indicative of at least one selected from the group consisting of the first type of pressure failure and the second type of pressure failure.

Abstract: A crawler track includes a link and is driven in a direction of travel by a sprocket having a plurality of teeth. The link includes a pad, a first grouser, and a second grouser. The pad defines a first surface, a second surface opposite the first surface, a first end, and a second end spaced apart from the first end along the direction of travel. The pad defines at least one opening extending through the pad between the first surface and the second surface, and the opening is operable to receive a sprocket tooth. The first grouser is positioned on the first surface proximate the first end of the pad, while the second grouser is positioned on the first surface proximate the second end of the pad. The first grouser and the second grouser extend in a direction substantially perpendicular to the direction of travel of the track.

Abstract: A control system monitors the angle of each ranging arm, with respect to the mainframe of the machine. While the machine is in a defined zone along the face, if the angle of the arm is detected to be lower than a parameter defined set-point called the undercut limit, the control system does not allow the arm to be lowered further. When entering the run of face from either gate end, if either of the ranging arms are below the set point, the horizontal movement of the shearer is stopped, and an alarm message is generated, and a warning light begins to flash, alerting the operator that he must raise the arm before horizontal movement of the shearer can be enabled.