Abstract: Systems and methods are used to control operation of a rotary compressor of a refrigeration system to improve efficiency by varying the volume ratio and the speed of the compressor in response to current operating and load conditions. The volume of the axial and/or radial discharge ports of the compressor can be varied to provide a volume ratio corresponding to operating conditions. In addition, permanent magnet motors and/or control of rotor tip speed can be employed for further efficiency gains.

Abstract: Systems and methods are used to control operation of a rotary compressor of a refrigeration system to improve efficiency by varying the volume ratio and the speed of the compressor in response to current operating and load conditions. The volume of the axial and/or radial discharge ports of the compressor can be varied to provide a volume ratio corresponding to operating conditions. In addition, permanent magnet motors and/or control of rotor tip speed can be employed for further efficiency gains.

Abstract: Systems and methods for controlling a conveyor in a mining system. The conveyor includes a sprocket, a chain, a hydraulic cylinder, one or more sensors, and a controller. In one implementation, the method includes sensing a characteristic associated with the conveyor, generating a signal based on the characteristic, determining a tension associated with the chain based on the signal, determining an amount of chain stretch based on the tension, and modifying a position of the hydraulic cylinder based on the amount of chain stretch.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: Systems and methods for controlling a conveyor in a mining system. The conveyor includes a sprocket, a chain, a hydraulic cylinder, one or more sensors, and a controller. In one implementation, the method includes sensing a characteristic associated with the conveyor, generating a signal based on the characteristic, determining a tension associated with the chain based on the signal, determining an amount of chain stretch based on the tension, and modifying a position of the hydraulic cylinder based on the amount of chain stretch.

Abstract: Systems and methods for controlling a conveyor in a mining system. The conveyor includes a sprocket, a chain, a hydraulic cylinder, one or more sensors, and a controller. In one implementation, the method includes sensing a characteristic associated with the conveyor, generating a signal based on the characteristic, determining a tension associated with the chain based on the signal, determining an amount of chain stretch based on the tension, and modifying a position of the hydraulic cylinder based on the amount of chain stretch.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: Systems and methods are used to control operation of a rotary compressor of a refrigeration system to improve efficiency by varying the volume ratio and the speed of the compressor in response to current operating and load conditions. The volume of the axial and/or radial discharge ports of the compressor can be varied to provide a volume ratio corresponding to operating conditions. In addition, permanent magnet motors and/or control of rotor tip speed can be employed for further efficiency gains.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: A conveyor and a dowel assembly. The dowel assembly may generally include a dowel body positioned between the frame and the housing and a seal arrangement. The seal arrangement may include an end seal member engageable with the end wall of the recess, and a side seal member engageable with the side wall of the recess, and a carrier member supported by the dowel body and supporting one of the end seal member and the side seal member, the carrier member being supported for movement relative to the dowel body to provide engagement of the one of the end seal member and the side seal member with the associated one of the end wall and the side wall.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: Systems and methods for controlling a conveyor in a mining system. The conveyor includes a sprocket, a chain, a hydraulic cylinder, one or more sensors, and a controller. In one implementation, the method includes sensing a characteristic associated with the conveyor, generating a signal based on the characteristic, determining a tension associated with the chain based on the signal, determining an amount of chain stretch based on the tension, and modifying a position of the hydraulic cylinder based on the amount of chain stretch.

Abstract: A rack bar haulage system including a plurality of rack bars, each having spaced apart gear teeth extending between cheek sections at opposite sides of the rack bar. The haulage system also includes a clog including two spaced apart sidewalls, and openings through the sidewalls. One cheek section has a clog wall receiving cavity adapted to receive one of the clog sidewalls, the clog wall receiving cavity being defined by spaced apart cheek section flanges. The cheek section flanges each have an opening there through, and the cheek section flange openings are aligned with the clog sidewall openings. A pin is insertable through the sidewall openings and the openings in the cheek section flanges, and the spaced apart cheek sections are positioned so that the envelope formed by the gear teeth is at the same level on the rack bar as the pin for retaining the rack bar in the clog.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: A conveyor and a dowel assembly. The dowel assembly may generally include a dowel body positioned between the frame and the housing and a seal arrangement. The seal arrangement may include an end seal member engageable with the end wall of the recess, and a side seal member engageable with the side wall of the recess, and a carrier member supported by the dowel body and supporting one of the end seal member and the side seal member, the carrier member being supported for movement relative to the dowel body to provide engagement of the one of the end seal member and the side seal member with the associated one of the end wall and the side wall.

Abstract: A chain tension sensor for a chain conveyor, the conveyor including a frame and a chain having a plurality of flights. The tension sensor includes a reaction arm and a load sensing pin. The reaction arm includes a first end, a second end opposite the first end, and a load pad. The first end is pivotably coupled to the frame by a pivot pin defining a pivot axis. The load pad is adjacent the conveyor chain and positioned to contact flights passing the load pad. The flights contacting the load pad exert a force on the reaction in a direction that is perpendicular to the pivot axis. The load sensing pin is coupled to the reaction arm such that the load sensing pin senses the force that is exerted by the flights.

Abstract: A link chain comprises a chain link including two shank portions and two arc portions connecting the two shank portions. The two shank portions and the two arc portions define an interior space of the first chain link; and a dividing element extends inwardly from an inside surface of one of the two shank portions and extends inwardly from the inside surface of the other shank portion. The dividing element divides the interior space into two movement spaces, and the dividing element has a centerline, and the centerline is not a straight line perpendicular to the shank.

Abstract: A rack bar haulage system including a plurality of rack bars, each having spaced apart gear teeth extending between cheek sections at opposite sides of the rack bar. The haulage system also includes a clog including two spaced apart sidewalls, and openings through the sidewalls. One cheek section has a clog wall receiving cavity adapted to receive one of the clog sidewalls, the clog wall receiving cavity being defined by spaced apart cheek section flanges. The cheek section flanges each have an opening there through, and the cheek section flange openings are aligned with the clog sidewall openings. A pin is insertable through the sidewall openings and the openings in the cheek section flanges, and the spaced apart cheek sections are positioned so that the envelope formed by the gear teeth is at the same level on the rack bar as the pin for retaining the rack bar in the clog.