Patent Publication Number: US-11391149-B2

Title: Mining machine with articulating boom and independent material handling system

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of prior-filed, co-pending U.S. patent application Ser. No. 15/680,637, filed Aug. 18, 2017, U.S. Provisional Patent Application No. 62/377,150, filed Aug. 19, 2016, and U.S. Provisional Patent Application No. 62/398,834, filed Sep. 23, 2016. The entire contents of these documents are incorporated by reference herein. 
    
    
     BACKGROUND 
     The present disclosure relates to mining and excavation machines, and in particular to a cutting device for a mining or excavation machine. 
     Hard rock mining and excavation typically requires imparting large energy on a portion of a rock face in order to induce fracturing of the rock. One conventional technique includes operating a cutting head having multiple mining picks. Due to the hardness of the rock, the picks must be replaced frequently, resulting in extensive down time of the machine and mining operation. Another technique includes drilling multiple holes into a rock face, inserting explosive devices into the holes, and detonating the devices. The explosive forces fracture the rock, and the rock remains are then removed and the rock face is prepared for another drilling operation. This technique is time-consuming and exposes operators to significant risk of injury due to the use of explosives and the weakening of the surrounding rock structure. Yet another technique utilizes roller cutting element(s) that rolls or rotates about an axis that is parallel to the rock face, imparting large forces onto the rock to cause fracturing. 
     SUMMARY 
     In one aspect, a cutting assembly for a rock excavation machine having a frame includes a boom supported on the frame and a cutting device. The boom includes a first portion and a second portion. The first portion includes a first structure and a second structure slidable relative to the first structure. The second portion includes a first member pivotably coupled to the second structure, and a second member pivotably coupled to the first member. The cutting device is supported on the second member. 
     In another aspect, a cutting assembly for a rock excavation machine having a frame includes a boom and a cutting device. The boom includes a first end supported on the frame and a second end. The boom further includes a first portion adjacent the first end and a second portion adjacent the second end. The second portion is supported for movement relative to the first end by a telescopic coupling and is pivotable relative to the first portion about an axis. The cutting device is supported on the second end of the boom. 
     In yet another aspect, a rock excavation machine includes a chassis, a boom supported on the chassis, a cutting device supported on the boom, and a material handling device supported on the chassis independently of the boom. At least a portion of the boom is movable relative to the chassis between a retracted position and an extended position. The material handling device is movable relative to the chassis between a retracted position and an extended position independent of the boom. 
     Other aspects will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a mining machine. 
         FIG. 2  is side view of the mining machine of  FIG. 1 . 
         FIG. 3  is a top view of the mining machine of  FIG. 1 . 
         FIG. 4  is a top view of the mining machine of  FIG. 1  with a boom in a pivoted position. 
         FIG. 5  is a front view of the mining machine of  FIG. 1 . 
         FIG. 6  is a side view of a portion of the boom in a retracted position. 
         FIG. 7  is a side view of a portion of the boom in an extended position. 
         FIG. 8  is a cross-section view of a portion of the boom of  FIG. 2 , viewed along section  8 - 8 . 
         FIG. 9  is a cross-section view of a portion of the boom of  FIG. 2 , viewed along section  9 - 9 . 
         FIG. 10  is an enlarged view of portion  10 - 10  of the cross-section view of  FIG. 8 . 
         FIG. 11  is a cross-section view of a portion of the mining machine of  FIG. 5 , viewed along section  11 - 11 . 
         FIG. 12  is a side view of a portion of the mining machine with a boom in a lower position. 
         FIG. 13  is a perspective view of a portion of the mining machine of  FIG. 12  with the boom in a lower position. 
         FIG. 14  is a side view of a portion of the mining machine with a boom in an upper position. 
         FIG. 15  is a perspective view of a portion of the mining machine of  FIG. 14  with the boom in an upper position. 
         FIG. 16  is an enlarged perspective view of a cutter head. 
         FIG. 17  is an enlarged perspective view of the cutter head of  FIG. 16 , with the boom in a lower position. 
         FIG. 18  is a schematic top view of a portion of the mining machine of  FIG. 4 , with a cutter head engaging a rock wall. 
         FIG. 19  is a cross-section view of the cutter head of  FIG. 16 , viewed along section  19 - 19 . 
         FIG. 20  is a cross-section view of the mining machine of  FIG. 5 , viewed along section  11 - 11 , with the gathering head in a retracted position. 
         FIG. 21  is an enlarged side view of the mining machine of  FIG. 2  with the gathering head in a retracted position. 
         FIG. 22  is a cross-section view of the mining machine of  FIG. 5 , viewed along section  11 - 11 , with the gathering head in an extended position. 
         FIG. 23  is an enlarged side view of the mining machine of  FIG. 2  with the gathering head in an extended position. 
         FIG. 24  is a cross-section view of a portion of the mining machine of  FIG. 1 . 
     
    
    
     Before any embodiments are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “mounted,” “connected” and “coupled” are used broadly and encompass both direct and indirect mounting, connecting and coupling. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings, and can include electrical or fluid connections or couplings, whether direct or indirect. Also, electronic communications and notifications may be performed using any known means including direct connections, wireless connections, etc. 
     DETAILED DESCRIPTION 
       FIGS. 1-4  illustrate a mining machine  10  (e.g., an entry development machine) including a chassis  14 , a boom  18 , a cutter head  22  for engaging a rock face  30  ( FIG. 18 ), and a material handling system  34 . In the illustrated embodiment, the chassis  14  is supported on a crawler mechanism  42  for movement relative to a floor (not shown). The chassis  14  includes a first or forward end and a second or rear end, and a longitudinal chassis axis  50  extends between the forward end and the rear end. The boom  18  is supported on the chassis  14  by a turntable or swivel joint  54 . The swivel joint  54  ( FIG. 2 ) is rotatable about a swivel axis  58  that is perpendicular to the chassis axis  50  (e.g., a vertical axis perpendicular to the support surface) to pivot the boom  18  in a plane that is generally parallel the chassis axis  50  (e.g., a horizontal plane parallel to the support surface). In the illustrated embodiment, the chassis  14  includes slew actuators or cylinders  66  for pivoting the swivel joint  54  and the boom  18  laterally about the swivel axis  58 . 
     As shown in  FIGS. 2-4 , the machine  10  also includes a service support member or bridge  62  extending between the chassis  10  and the boom  18 . In the illustrated embodiment, the bridge  62  includes a first portion  62   a  coupled to the chassis  14 , a second portion  62   b  coupled to the boom  18 , and an intermediate portion  68   c  coupled between the first portion  62   a  and the second portion  62   c . The second portion  62   b  is substantially aligned with the swivel axis  58  but does not rotate with the boom  18 . In some embodiments, a bearing (not shown) permits sliding movement between the second portion  62   b  and the boom  18 . The intermediate portion  68   c  may be rigidly secured at each end to the first portion  68   a  and second portion  62   b , respectively, or a coupling (e.g., a spherical joint) may permit some relative movement. The bridge  62  supports and/or guides various service lines (e.g., conduits, cables, wires, hoses, and pipes not shown) between the chassis  14  and the boom  18 . The service lines may include electrical slip rings, rotary unions, or manifolds at connection points. 
     As shown in  FIG. 2 , the boom  18  includes a first portion or base portion  70  and a second portion or wrist portion  74  supporting the cutter head  22 . Referring to  FIGS. 6 and 7 , in the illustrated embodiment, the wrist portion  74  is pivotably coupled to the base portion  70  by a pin joint  78 . The base portion  70  includes a first or stationary structure  86  secured to the swivel joint  54  and a second or movable structure  90 . The stationary structure  86  is pivotable with the swivel joint  54  and includes an opening  94  ( FIG. 8 ) receiving the movable structure  90 . The movable structure  90  is movable relative to the stationary structure  86  in a telescoping manner along a base axis  98 . Linear actuators or slide actuators  102  (e.g., fluid cylinders) may be coupled between the stationary structure  86  and the movable structure  90  to move the movable structure  90  between a retracted position ( FIG. 6 ) and an extended position ( FIG. 7 ). The slide actuators  102  may be coupled to the exterior surfaces of the stationary structure  86  and the movable structure  90 . In some embodiments, a sensor (e.g., a transducer—not shown) measures the stroke or position of the slide actuators  102 . 
     As shown in  FIG. 8 , the movable structure  90  is supported relative to the stationary structure  86  by bearing assemblies  110 . In the illustrated embodiment, six bearing assemblies  110  are located in a common plane normal to the base axis  98 , with two bearing assemblies  110  abutting the upper and lower surfaces of the movable structure  90  and one bearing assembly  110  abutting each lateral surface of the movable structure  90 . 
     As shown in  FIG. 9 , an additional set of bearing assemblies  110  may be positioned in a second plane normal to the base axis  98  and axially offset from the plane illustrated in  FIG. 8 . In the illustrated embodiment, the second set includes four bearing assemblies  110 , with one bearing assembly  110  abutting each surface of the movable structure  90 . In other embodiments, the base portion  70  may include fewer or more bearing assemblies  110 , and the bearing assemblies  110  may be positioned in additional planes along the length of the base axis  98 . The bearing assemblies  110  may be positioned in a different manner. In the illustrated embodiment, the bearing assemblies  110  are accessible from an outer surface of the boom  18 ; in other embodiments, the bearing assemblies  110  may be accessible only from an interior portion of the boom  18 . 
     As shown in  FIG. 10 , each bearing assembly  110  includes a main support  118  secured to the base portion  70  and a pad  122  abutting a surface of the movable structure  90 . In addition, a spherical bearing member  126  is coupled to the main support  118  to permit pivoting movement of the pad  122  relative to the main support  118 . The pad  122  includes one or more pockets or chambers or galleries  130  formed in a surface of the pad  122  adjacent the movable structure  90 . The main support  118  includes a port  134  and a passage  138  providing communication between the port  134  and galleries  130 . The port  134  may receive a lubricant (e.g. grease) through a manual feed or an automatic lubrication system, and the lubricant may be transferred to the galleries  130  to lubricate the interface between the pad  122  and the movable structure  90 . In addition, in the illustrated embodiment, a hard, low-friction bearing surface  146  is secured to an outer surface of the movable structure  90 . The bearing surface  146  may be removably secured to the movable structure  90  (e.g., by fasteners) or attached by fusion (e.g., welding). The bearing assemblies  110  provide a low-friction interface and are capable of transmitting large forces caused by the cutting operation. 
     In addition, a shim pack  150  may be positioned between the main support  118  and the stationary structure  86  to adjust the position of the main support  118 . A spring pack (not shown) may be positioned between the main support  118  and the spherical bearing member  126  to provide an initial load or preload to ensure that the pad  122  maintains positive contact with the movable structure  90  during operation. In other embodiments, other types of bearing assemblies may be used. 
     As shown in  FIG. 11 , the wrist portion  74  is pivotable relative to the base portion  70  due to operation of one or more fluid actuators (e.g., hydraulic cylinder) or luff actuators  162 . In the illustrated embodiment, extension and retraction of the luff actuators  162  causes the wrist portion  74  to pivot about a transverse axis  166  that is perpendicular to the base axis  98 . The wrist portion  74  may be pivoted between a first or lower position ( FIGS. 12 and 13 ) and a second or upper position ( FIGS. 14 and 15 ), or an intermediate position between the lower position and the upper position. Stated another way, the luff actuators  162  drive the wrist portion  74  to pivot in a plane that is parallel to the base axis  98  and the plane generally extends between an upper end of the machine  10  and a lower end of the machine  10 . 
     In the illustrated embodiment, each luff actuator  162  includes a first end and a second end, with the first end coupled to the movable structure  90  of the base portion  70  and the second end coupled to the wrist portion  74 . Each actuator  162  extends through the base portion  70  of the boom  18 , such that the actuators  162  are positioned in the movable structure  90 . Also, the transverse axis  166  may be offset from the base axis  98  such that the transverse axis  166  and the base axis  98  do not intersect each other. In the illustrated embodiment, the machine  10  includes two luff cylinders  162 ; in other embodiments, the machine  10  may include fewer or more actuators  162 . 
     As shown in  FIGS. 16 and 17 , the wrist portion  74  includes a first member  174  proximate a first end  178  and a second member  182  proximate a second end  186 , and a wrist axis  190  extends between the first end  178  and the second end  186 . The first end  178  of the wrist portion  74  is coupled to the movable structure  90  of the base portion  70 , and therefore the wrist portion  74  translates or telescopes with the movable structure  90  in a direction parallel to the base axis  98 . The cutter head  22  ( FIG. 16 ) is positioned adjacent the second end  186  of the wrist portion  74 . 
     The cutter head  22  is positioned adjacent a distal end of the boom  18 . As shown in  FIG. 16 , in the illustrated embodiment the cutter head  22  includes a cutting member or bit or cutting disc  202  having a peripheral edge  206 , and a plurality of cutting bits  210  ( FIG. 19 ) are positioned along the peripheral edge  206 . The peripheral edge  206  may have a round (e.g., circular) profile, the cutting bits  210  may be positioned in a common plane defining a cutting plane  214  ( FIG. 18 ). The cutting disc  202  may be rotatable about a cutter axis  218  that is generally perpendicular to the cutting plane  214 . In the illustrated embodiment, the cutter axis  218  is aligned with the wrist axis  190  ( FIG. 18 ). 
     As shown in  FIG. 18 , the wrist portion  74  includes a universal joint or U-joint  226  coupling the first member  174  and the second member  182 . In particular, the first member  174  includes a pair of parallel first lugs  234  and the second member  182  includes a pair of parallel second lugs  238 . A first shaft  242  extends between the first lugs  234  and a second shaft  246  extends between the second lugs  238  and is coupled to the first shaft  242 . In some embodiments, the second shaft  246  is rigidly coupled to the first shaft  242 . The first shaft  242  defines a first axis  250  that is substantially perpendicular to the wrist axis  190 , and the second shaft  246  defines a second axis  254 . The second axis  254  may be substantially perpendicular to the cutter axis  218  ( FIG. 16 ). The first axis  250  and the second axis  254  are oriented perpendicular to each other. The universal joint  226  allows the second member  182  to pivot relative to the first member  174  about the first axis  250  and the second axis  254 . Other aspects of universal joints are understood by a person of ordinary skill in the art and are not discussed in further detail. Among other things, the incorporation of the universal joint  226  permits the cutter head  22  to precess about the axes  250 ,  254  of the universal joint  226 , and the joint  226  is capable of transferring shear and torque loads. 
     The cutter head  22  engages the rock face  30  by undercutting the rock face  30 . The cutting disc  202  traverses across a length of the rock face  30  in a cutting direction  266 . A leading portion of the cutting disc  202  engages the rock face  30  at a contact point and is oriented at an angle  262  relative to a tangent of the rock face  30  at the contact point. The cutting disc  202  is oriented at an acute angle  262  relative to a tangent of the rock face  30 , such that a trailing portion of the cutting disc  202  (i.e., a portion of the disc  202  that is positioned behind the leading portion with respect to the cutting direction  266 ) is spaced apart from the face  30 . The angle  262  provides clearance between the rock face  30  and a trailing portion of the cutting disc  202 . 
     In some embodiments, the angle  262  is between approximately 0 degrees and approximately 25 degrees. In some embodiments, the angle  262  is between approximately 1 degree and approximately 10 degrees. In some embodiments, the angle  262  is between approximately 3 degrees and approximately 7 degrees. In some embodiments, the angle  262  is approximately 5 degrees. 
     Referring again to  FIGS. 16 and 17 , the wrist portion  74  further includes a suspension system for controlling movement of the second member  182  relative to the first member  174 . In the illustrated embodiment, the suspension system includes multiple suspension actuators  270  (e.g., hydraulic cylinders). The suspension actuators  270  may be independently operated to maintain a desired offset angle  274  ( FIG. 18 ) between the first member  174  and the second member  182 . In addition, the suspension actuators  270  may be filled with fluid and act similar to springs to counteract the reaction forces exerted on the cutter head  22  by the rock face  30 . 
     In the illustrated embodiment, the suspension system includes four fluid cylinders  270  spaced apart from one another about the wrist axis  190  by an angular interval of approximately 90 degrees. The cylinders  270  extend in a direction that is generally parallel to the wrist axis  190 , but the cylinders  270  are positioned proximate the end of each of the first shaft  242  and the second shaft  246  of the universal joint  226 . Each fluid cylinder  270  includes a first end coupled to the first member  174  and a second end coupled to the second member  182 . The ends of each cylinder  270  may be connected to the first member  174  and the second member  182  by spherical couplings to permit pivoting movement. The suspension system transfers the cutting force as a moment across the universal joint  226 , and controls the stiffness between the first member  174  and the second member  182 . 
     In other embodiments, the suspension system may include fewer or more suspension actuators  270 . The suspension actuators  270  may be positioned in a different configuration between the first member  174  and the second member  182 . In still other embodiments, the suspension system may incorporate one or more mechanical spring element(s) either instead of or in addition to the fluid cylinders  270 . Also, in some embodiments, a fluid manifold  184  (e.g., a sandwich manifold— FIGS. 16 and 17 ) may be positioned between the first member  174  and the universal joint  226  to provide fluid communication to the suspension actuators  270 . 
     As shown in  FIG. 19 , the cutter head  22  is positioned adjacent a second end  186  of the wrist portion  74  ( FIG. 16 ). The cutting disc  202  is rigidly coupled to a carrier  282  that is supported on a shaft  286  for rotation (e.g., by straight or tapered roller bearings  288 ) about the cutter axis  218 . The cutter head  22  further includes a housing  290 . In the illustrated embodiment, the housing  290  is positioned between the second end  186  of the wrist portion  74  and the shaft  286 , and the housing  290  is formed as a separate structure that is removably coupled to the second end  186  of the wrist portion  74  (e.g., by fasteners) and is removably coupled to the shaft  286  (e.g., by fasteners). In some embodiments, the housing  290  is formed as multiple separate sections that are coupled together. 
     The housing  290  supports an excitation element  302 . The excitation element  302  includes an exciter shaft  306  and an eccentric mass  310  positioned on the exciter shaft  306 . The exciter shaft  306  is driven by a motor  314  and is supported for rotation (e.g., by straight or tapered roller bearings  316 ) relative to the housing  290 . The rotation of the eccentric mass  310  induces an eccentric oscillation in the housing  290 , the shaft  286 , and the cutting disc  202 . The excitation element  302  and cutter head  22  may be similar to the exciter member and cutting bit described in U.S. Publication No. 2014/0077578, published Mar. 20, 2014, the entire contents of which are hereby incorporated by reference. In the illustrated embodiment, the cutting disc  202  is supported for free rotation relative to the shaft  286 ; that is, the cutting disc  202  is neither prevented from rotating nor positively driven to rotate except by the induced oscillation caused by the excitation element  302  and/or by the reaction forces exerted on the cutting disc  202  by the rock face  30 . 
     Referring now to  FIG. 20 , the material handling system  34  includes a gathering head  316  and a conveyor  318 . The gathering head  316  includes an apron or deck  322  and rotating arms  326  ( FIG. 5 ). As the machine  10  advances, the cut material is urged onto the deck  322 , and the rotating arms  326  move the cut material onto the conveyor  318  for transporting the material to a rear end of the machine  10 . The conveyor  318  may be a chain conveyor driven by one or more sprockets  330 . In the illustrated embodiment, the conveyor  318  is coupled to the gathering head  316  by a pin joint  334  and is supported for movement relative to the chassis  14  by a roller  338  ( FIG. 24 ). In other embodiments, the arms may slide or wipe across a portion of the deck  322  (rather than rotating) to direct cut material onto the conveyor  318 . Furthermore, in other embodiments, the material handling system  34  may also include a pair of articulated arms, each of which supports a bucket for removing material from an area in front of the machine  10  and directing the material onto the deck  322 . 
     As shown in  FIG. 21 , the gathering head  316  and the conveyor  318  are coupled together and are supported for movement relative to the chassis  14 . Specifically, the gathering head  316  and conveyor  318  are coupled to the chassis  14  by a link  350  and a sumping actuator  354 . Although only one link  350  and sumping actuator  354  is shown in  FIG. 20 , it is understood that the machine  10  may include a similar link  350  and sumping actuator  354  on each side of the machine  10 . 
     In the illustrated embodiment, a first end of the link  350  is pivotably coupled to the chassis  14  (e.g., proximate an upper end of the front of the chassis  14 ) and a second end of the link  350  is pivotable coupled to the gathering head  316 . The sumping actuator  354  is coupled between the chassis  14  and the link  350  such that operation of the sumping actuator  354  moves the gathering head  316  and conveyor  318  relative to the chassis  14  (movement that is commonly referred to as “sumping”). The gathering head  316  and chassis  14  may be moved between a retracted position ( FIGS. 20 and 21 ) and an extended position ( FIGS. 22 and 23 ), and any intermediate position between the retracted position and the extended position. The stroke of the sumping actuators  354  may be measured with a sensor (e.g., an internal transducer—not shown). In some embodiments, the sumping actuators  354  include floating pistons to maintain the forward edge of the deck  322  against the ground. 
     In general, the coupling between the wrist portion  74  and the base portion  70  is positioned forward (i.e., distal) with respect to the telescoping coupling between the stationary structure  86  and the movable structure  90 . As a result, the articulating portion of the boom  18  is more compact, thereby reducing the area between the cutter head  22  and the forward edge of the gathering head  316 . Also, the material handling system  34  is coupled to the chassis  14  independent of the boom  18 . As a result, the material handling system  34  can be extended and retracted independent of the boom  18 . For example, the boom  18  may be extended relative to the chassis  14 , and the material handling system  34  may be extended by a distance that is greater than, less than, or equal to the extension of the boom  18 . This provides versatile control of the cutting and gathering operations. In some embodiments, the material handling system  34  can be extended and retracted through a linear distance of approximately 500 mm, and the boom  18  can be extended and retracted through a similar distance. 
     Although the cutter head  22  has been described above with respect to a mining machine (e.g., an entry development machine), it is understood that one or more independent aspects of the boom  18 , the cutter head  22 , the material handling system  34 , and/or other components may be incorporated into another type of machine and/or may be supported on a boom of another type of machine. Examples of other types of machines may include (but are not limited to) drills, road headers, tunneling or boring machines, continuous mining machines, longwall mining machines, and excavators. 
     Although various aspects have been described in detail with reference to certain embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects as described. Various features and advantages are set forth in the following claims.