A roof support includes a base, a canopy for engaging a mine surface, a shield coupled to the canopy, and a link coupled between the base and the shield. The canopy is supported relative to the base and includes an end configured to be spaced apart from a mine face by a distance. The link is movable between a first position and a second position, and movement of the link between the first position and the second position causing the distance to change.

A roof support includes a base, a canopy for engaging a mine surface, a shield coupled to the canopy, and a link coupled between the base and the shield. The canopy is supported relative to the base and includes an end configured to be spaced apart from a mine face by a distance. The link is movable between a first position and a second position, and movement of the link between the first position and the second position causing the distance to change.

The present invention pertains to a method for monitoring operation of a mining machine unit, particularly of a longwall mining system, having a shield unit connected to a material removing unit by means of an actuator for adjusting a distance between the shield unit and the material removing unit, the method comprises the steps of determining a position change of the shield unit during an actuating operation of the actuator; and a step of detecting a malfunction of the mining machine unit based on the determined position change.

A system for controlling a roof support, including a canopy for engaging a mine surface, includes a sensor configured to generate a signal indicative of a position of an end of the canopy, and a controller. The controller is configured to receive the signal and determine whether a portion of a mining machine will contact a portion of the canopy based on the signal.

A system for controlling a roof support, including a canopy for engaging a mine surface, includes a sensor configured to generate a signal indicative of a position of an end of the canopy, and a controller. The controller is configured to receive the signal and determine whether a portion of a mining machine will contact a portion of the canopy based on the signal.

A distributed coal cutting device for a Longwall face of a coal mine includes coal cutting units, where each coal cutting unit includes one coal cutting machine and two hydraulic supports, the two hydraulic supports are arranged side by side, the arrangement direction of the two hydraulic supports is parallel to the coal wall of the Longwall face, and the coal cutting machine is connected with one of the hydraulic supports. According to the device, multiple coal cutting machines are used for simultaneously carrying out coal cutting operation, and single-point coal cutting is changed into multiple-point simultaneous coal cutting, so that the coal cutting production capacity and the production efficiency are greatly improved. The multiple coal cutting machines can derive multiple control modes, so that the production flexibility and adaptability are improved.

A distributed coal cutting device for a Longwall face of a coal mine includes coal cutting units, where each coal cutting unit includes one coal cutting machine and two hydraulic supports, the two hydraulic supports are arranged side by side, the arrangement direction of the two hydraulic supports is parallel to the coal wall of the Longwall face, and the coal cutting machine is connected with one of the hydraulic supports. According to the device, multiple coal cutting machines are used for simultaneously carrying out coal cutting operation, and single-point coal cutting is changed into multiple-point simultaneous coal cutting, so that the coal cutting production capacity and the production efficiency are greatly improved. The multiple coal cutting machines can derive multiple control modes, so that the production flexibility and adaptability are improved.

A roof support includes a base, a canopy for engaging a mine surface, a shield coupled to the canopy, and a link coupled between the base and the shield. The canopy is supported relative to the base and includes an end configured to be spaced apart from a mine face by a distance. The link is movable between a first position and a second position, and movement of the link between the first position and the second position causing the distance to change.

A roof support includes a base, a canopy for engaging a mine surface, a shield coupled to the canopy, and a link coupled between the base and the shield. The canopy is supported relative to the base and includes an end configured to be spaced apart from a mine face by a distance. The link is movable between a first position and a second position, and movement of the link between the first position and the second position causing the distance to change.

A distributed coal cutting device for a Longwall face of a coal mine includes coal cutting units, where each coal cutting unit includes one coal cutting machine and two hydraulic supports, the two hydraulic supports are arranged side by side, the arrangement direction of the two hydraulic supports is parallel to the coal wall of the Longwall face, and the coal cutting machine is connected with one of the hydraulic supports. According to the device, multiple coal cutting machines are used for simultaneously carrying out coal cutting operation, and single-point coal cutting is changed into multiple-point simultaneous coal cutting, so that the coal cutting production capacity and the production efficiency are greatly improved. The multiple coal cutting machines can derive multiple control modes, so that the production flexibility and adaptability are improved.