Patent Publication Number: US-11020768-B2

Title: Vibratory classifiers

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Stage application of PCT/US2017/045844 filed Aug. 8, 2017 and claims the benefit of U.S. Provisional Patent Application Ser. No. 62/372,563, filed Aug. 9, 2016, and U.S. Provisional Patent Application Ser. No. 62/410,660, filed Oct. 20, 2016, all of which are incorporated by reference herein. 
     BACKGROUND 
     Vibratory classifiers (such as screens and feeders) use vibration to move material such as aggregate to separate the material into different constituent sized material elements. Grizzly bar classifiers generally are a spaced arrangement of structural metal beams (commonly referred to as grizzly bars) supported on a frame that are capable of supporting material that is larger than the spacing of the bars and allow material smaller than the spacing of the bars to pass between the bars. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of a vibratory classifier in a first configuration. 
         FIG. 2  is a perspective view of the vibratory classifier of  FIG. 1  in the first configuration, with certain components including a sidewall not shown for clarity. 
         FIG. 3  is a side elevation view of the vibratory classifier of  FIG. 1  in the first configuration, with certain components including a sidewall not shown for clarity. 
         FIG. 4  is a perspective view of the vibratory classifier of  FIG. 1  in a second configuration, with certain components including a sidewall not shown for clarity. 
         FIG. 5  is a side elevation view of the vibratory classifier of  FIG. 1  in the second configuration, with certain components (including a sidewall) not shown for clarity. 
         FIG. 6  is a perspective view of the vibratory classifier of  FIG. 1  in the first configuration with certain components including a grizzly bar classifier not shown for clarity. 
         FIG. 7  is a perspective view of the vibratory classifier of  FIG. 1  in the second configuration with certain components including a grizzly bar classifier not shown for clarity. 
         FIG. 8  is a bottom view of the vibratory classifier of  FIG. 1 . 
         FIG. 9  is an enlarged partial bottom view of the vibratory classifier of  FIG. 1  illustrating the grizzly bar classifier. 
         FIG. 10  is an enlarged perspective view of the vibratory classifier of  FIG. 1  illustrating a spring assembly having a lift support. 
         FIG. 11  is a perspective view of the vibratory classifier of  FIG. 1  with certain components including a grizzly bar classifier and supports removed for clarity. 
         FIG. 12  is a side elevation view of the vibratory classifier of  FIG. 1  with certain components including a grizzly bar classifier and supports removed for clarity. 
         FIG. 13  is a partial side elevation view of another embodiment of a vibratory classifier. 
         FIG. 14  is a partial side elevation view of a sidewall of the vibratory classifier of  FIG. 13 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 through 12 , one embodiment of a vibratory classifier is illustrated in two configurations. Various embodiments may be referred to as feeders or grizzly feeders. In some embodiments, although not required, a spring assembly of the vibratory feeder may include a lift support. In some embodiments, a classifying deck (e.g., grizzly bar classifier which may be referred to as a cassette) and corresponding supports are adjustable between a plurality of (e.g., at least two) configurations. 
     Turning to  FIG. 1 , a vibratory feeder  2200  is illustrated in a first configuration. A deck having an upper surface  2240  is optionally disposed to receive aggregate and/or other material to be classified. The upper surface  2240  is optionally disposed generally horizontally or in some embodiments at a downwardly-sloping angle between sidewalls  2210 ,  2220  of the feeder. A general direction of travel T of aggregate material on surface  2240  is illustrated in  FIG. 1 , although it should be appreciated that the path of travel of material on the surface may include complex movement as the material bounces against the surface. 
     The feeder  2200  is optionally driven for vibration by a vibration assembly  2250  (e.g., including one or more eccentric shafts which may be disposed at a lower end of the feeder, including one or more eccentric weights, etc.). Referring to  FIGS. 1 and 8 , a first drive housing  2258  may contain one or more driven elements (e.g., gears) for driving one or more shafts (e.g., eccentric shafts, non-eccentric shafts, etc.) which are optionally housed in a shaft housing  2256 . The drive elements and shafts are optionally driven by a drive wheel  2259  (e.g., sheave) which is optionally directly or indirectly driven by a motor (not shown) such as an electric motor. The shafts optionally extend transversely across the width of the feeder  2200  and are optionally driven and/or supported by drive elements (e.g., gears, bearings, wheels, etc.) disposed in a second drive housing  2252 . One or more eccentric weights are optionally supported on the shaft (e.g., near left and right ends of the shaft). The drive housing  2252  is optionally supported on the sidewall  2210 , e.g., by being mounted to a plate  2254  supported on the sidewall  2210 . It should be appreciated that other mechanisms may be employed to vibrate the feeder  2200  in various embodiments. 
     Referring to  FIGS. 2, 3 and 8 , the feeder  2200  is optionally resiliently supported on a plurality of spring assemblies which may vary in configuration and location in various embodiments. In some embodiments, the feeder  2200  is supported on left and right forward spring assemblies  2240 - 1 ,  2240 - 2 , respectively. In some embodiments, the feeder  2200  is supported on rearward spring support assembly  2260  which may include a plurality of springs  2262  (e.g.,  2262   a ,  2262   b ,  2262   c ,  2262   d ,  2262   e ) which are optionally disposed in transverse relation at least partially along the width of the feeder. 
     The upper surface  2240  optionally comprises one or more removable plates  2244  (e.g.,  2244   a ,  2244   b ,  2244   c ,  2244   d ). The plates  2244  may comprise a wear resistant material such as abrasion-resistant steel. The plates  2244  may be removably mounted (e.g., by fasteners such as bolts) to one or more support plates  2205 . The support plate  2205  is optionally supported on (e.g., welded to) a plurality of supports  2290  (e.g., I-beams). Supports  2290  are optionally disposed at least partially along the length of the surface  2240  and optionally welded to sidewalls  2210 ,  2220  at opposing ends thereof. A forward support  2295  (e.g., a beam such as a channel beam, I-beam or other support) optionally supports (e.g., is welded to) a forward portion of the support plate  2205 . The forward support  2295  is optionally mounted (e.g., by welding) to sidewalls  2210 ,  2220  such as at opposing ends thereof. 
     Referring to  FIG. 2 , a portion of each sidewall  2210 ,  2220  optionally extends above the surface  2240 . A part (e.g., a substantial part) of the portion of each sidewall extending above surface  2240  is optionally protected by one or more removable side liners  2242  (e.g., plates). The side liners  2242  are optionally removably mounted (e.g., by fasteners such as bolts) to the respective sidewalls. The side liners  2242  optionally comprise a wear-resistant material such as abrasion-resistant metal (e.g., steel). 
     In various embodiments, vibration of the feeder  2200  may comprise a generally elliptical, circular, linear, or other motion or pattern. As shown in  FIG. 1 , vibration of the feeder  2200  optionally tends to urge aggregate material on the upper surface  2240  to advance (e.g., while bouncing on the surface  2240 ) generally along travel direction T from a rearward end thereof (e.g., adjacent to a rearward wall  2230  extending laterally between the sidewalls  2210 ,  2220 ) toward a forward end thereof (e.g., a forward edge of plate  2244   d ). One or more lifting eyes  2232  are optionally mounted (e.g., welded) to the rearward wall  2230  or elsewhere on the feeder to install or adjust a position of the feeder. Vibration of the feeder  2200  optionally tends to urge aggregate material on the upper surface  2240  to advance (e.g., while bouncing on the surface  2240 ) generally along the travel direction T from the surface  2240  onto a grizzly bar classifier  2300  which in some embodiments may be referred to as a classifying deck or cassette. 
     The grizzly bar classifier  2300  optionally comprises a series of longitudinally-extending grizzly bars  2310  (e.g., five grizzly bars). In various embodiments, the grizzly bars may comprise rods, rectangular beams, tubes or other structure. The grizzly bars  2310  are optionally disposed in transversely spaced-apart relation such that undersize material (e.g., aggregate material smaller than the transverse spacing between the bars) tends to fall through the classifier  2300 . The undersize material may be processed according to a first post-sorting process, e.g., may be directed by an undersize material chute (not shown) onto a conveyor or other processing equipment. Oversize material (e.g., aggregate material larger than the transverse spacing between bars  2310 ) optionally tends to fall off a generally forward end of the classifier  2300 . Oversize material may be processed according to second post-sorting process, e.g., may be directed by an oversize material chute (not shown) into an input opening of a rock crusher or other processing equipment. 
     In some embodiments, a grizzly finger classifier (e.g., including grizzly fingers and/or spring fingers) may be incorporated in addition to or alternatively to the grizzly bar classifier described herein. Some such grizzly finger classifiers may be adjustably mounted (e.g., in a fashion similar to the grizzly bar classifiers described herein.) Some grizzly bars or grizzly fingers incorporated in various embodiments may comprise single components or may comprise assemblies (e.g., bimetallic assemblies or assemblies made of a single type of metal or other material). The grizzly bars and/or grizzly fingers of various embodiments may be supported in two or more locations along a length thereof or may be supported at one end thereof (e.g., a rearward end thereof along a general direction of aggregate material travel). 
     The grizzly bar classifier  2300  is optionally carried on a support structure  2400  that is mounted to side walls  2210 ,  2220 . The support structure  2400  generally comprises one or more transverse support structures, such as support beams or support plates. In one embodiment, support structure  2400  comprises first and second supports and optionally comprises a rearward support  2410  and a forward support  2420 . The rearward support  2410  is optionally generally laterally oriented and may be removably mounted at lateral ends thereof to the sidewalls  2210 ,  2220 . The forward support  2420  is optionally generally laterally oriented and is optionally removably mounted at lateral ends thereof to the sidewalls  2210 ,  2220 . 
     Comparing  FIGS. 3 and 5 , in  FIG. 3  the vibratory classifier  2200  is illustrated in a first configuration in which the grizzly bars of grizzly bar classifier  2300  are oriented at a first angle (e.g., 5 degrees below horizontal, between 4 and 6 degrees below horizontal, about 5 degrees below horizontal, less than about 10 degrees below horizontal, 5 degrees below the plane of surface  2240 , about 5 degrees below the plane of surface  2240 , less than 10 degrees below the plane of surface  2240  etc.). In the illustrated embodiment the upper surface  2240  is generally level (e.g., horizontal). In alternative embodiments, the grizzly bar classifier  2300  is disposed at an angle above horizontal. In  FIG. 5 , the vibratory classifier is illustrated in a second configuration (denoted  2200 ′) in which the grizzly bar classifier  2300  is oriented at a second angle with (e.g., about 0 degrees below horizontal, 0 degrees below horizontal, generally parallel to the plane of surface  2240 , etc.). In some embodiments, the support  2400  is in a first position in the first configuration and in a second position in the second configuration. 
     Referring to  FIGS. 4-6 and 9 , an exemplary embodiment of the classifier  2300  and support  2400  is illustrated in more detail. In the illustrated embodiment, each grizzly bar  2310  is tapered at forward and rearward end thereof; in other embodiments, the grizzly bars may be of a different shape or configuration. In some embodiments, the grizzly bar includes an upper contact portion  2312 . Each contact portion  2312  optionally has a width which tapers from the rearward to the forward end thereof; in other embodiments, the contact portion may be of constant width or of a different shape or configuration. In some embodiments, the contact portion  2312  is omitted or replaced with other structure. In some embodiments, the grizzly bar has a different cross-section (e.g., circular, elliptical, rectangular, square, etc.) such that aggregate material contacts an upper surface of the grizzly bar. 
     The grizzly bars  2310  are optionally removably mounted to the supports  2400 . In the illustrated embodiments, forward and rearward mounting footings  2324 ,  2314 , respectively are provided on either or both lateral sides of each bar  2310  for securing the bar to each support  2400 . A fastener (e.g., bolt and nut combination) optionally secures each mounting footing to the support  2400 . In the illustrated embodiment, a fastener  2325  (e.g., a bolt thereof) extends through each forward mounting footing  2324 , optionally through the forward support  2420 , and optionally through a mounting plate  2   326  disposed on the bottom of the forward support  2420 . In the illustrated embodiment, a fastener  2315  (e.g., a bolt thereof) extends through each rearward mounting footing  2314 , optionally through the rearward support  2410 , and optionally through a mounting plate  2316  disposed on the bottom of the rearward support  2410 . Tightening of each fastener  2315 ,  2325  removably fixes the associated mounting footing (and optionally the associated plate) to the support. 
     The rearward support  2410  optionally comprises one or more support beams or other structure which in various embodiments may be of various configurations (e.g., closed, open, generally rectangular, tubular, etc.). In one embodiment, rearward support  2410  comprises a pair of spaced beams, e.g., rearward beam  2414   a  and a forward beam  2414   b ). In the illustrated embodiment, the beams  2414  are mounted (e.g., by welding) at laterally opposing ends to mounting plates  2412 - 1  and  2412 - 2 . In some embodiments, the mounting plates  2412  include openings for receiving an array of fasteners  2480 . The fasteners  2480  are used in some embodiments to mount the rearward support  2410  to corresponding openings in the sidewall  2210 . 
     The forward support  2420  optionally comprises one or more support beams or other structure which in various embodiments may be of various configurations (e.g., closed, open, generally rectangular, tubular, etc.). In one embodiment, forward support  2420  comprises beams (e.g., rearward beam  2424   a  and a forward beam  2424   b ). In the illustrated embodiment, the beams  2424  are mounted (e.g., by welding) at laterally opposing ends to mounting plates  2422 - 1  and  2422 - 2 . In some embodiments, the mounting plates  2422  include openings for receiving an array of fasteners  2490 . The fasteners  2490  are used in some embodiments to mount the rearward support  2410  to corresponding openings in the sidewall  2220 . 
     An array of openings is optionally provided in each sidewall (or other supporting structure) for removably mounting each mounting plate of the support  2400  with associated fasteners. In some embodiments, a plurality of (e.g., two) arrays of openings are provided for each mounting plate; one of each plurality of arrays of openings may be selected in order to select an orientation of the support  2400  and thus of the classifier  2300  supported by the support  2400 . 
     In the illustrated embodiment, each rearward support  2410  includes openings for receiving an array of fasteners  2480 . The array of fasteners  2480  may include four fasteners  2481 ,  2482 ,  2483 ,  2484  as illustrated. The array of fasteners  2480  is optionally arranged generally in a polygonal (e.g., rectangular arrangement external to the beams  2414 . An additional fastener  2485  is optionally disposed between the beams  2414 . 
     In the illustrated embodiment, each forward support  2420  includes openings for receiving an array of fasteners  2490 . The array of fasteners  2490  may include four fasteners  2491 ,  2492 ,  2493 ,  2494  as illustrated. The array of fasteners  2490  is optionally arranged external to the beams  2424 . Fasteners  2491  and  2494  are separated by a first distance (e.g., height) which is optionally less than a second distance (e.g., height) separating fasteners  2492  and  2493 . An additional fastener  2495  is optionally disposed between the beams  2424 . The arrangement of the array of fasteners  2480  is optionally different from the arrangement of the array of fasteners  2490 . In some embodiments, the array of fasteners  2490  forms an irregular polygon (e.g., rectangle). 
     Referring to  FIGS. 11 and 12 , in some embodiments arrays of openings  3400 - 1 ,  3400 - 2  are provided in each sidewall  2210 ,  2220 , respectively, for removably mounting the support  2400  in one or more configurations. In some embodiments each array of openings  3400  includes a lower array  3401  for removably mounting the support  2400  in the first configuration (e.g., 5 degrees below horizontal). In some embodiments each array of openings  3400  includes an upper array  3402  for removably mounting the support  2400  in the second configuration (e.g., generally horizontal). In the illustrated embodiment, the upper array  3402  and the lower array  3401  overlap in the sense that individual openings of the lower array are disposed higher than individual openings of the upper array. However, individual openings of the upper and lower arrays optionally do not overlap and optionally are separated by at least a threshold distance (e.g., one millimeter, five millimeters, 10 millimeters, 20 millimeters, 50 millimeters a quarter-inch, a half-inch, an inch, two inches, etc.). The threshold distance optionally leaves sufficient material between openings such that the strength of the sidewall (e.g., the portion of the sidewall between the openings) is not substantially compromised by the proximity of the openings. In some embodiments, one or more openings of the first and second forward arrays of openings  3430 ,  3440  (e.g., all openings, at least one opening, two or more openings, three or more openings) in one or both sidewalls  2210 ,  2220  have a diameter D. Referring to  FIG. 12 , in various embodiments, the threshold distance Dt between any opening in the upper array  3430  and any opening in the lower array  3440  is optionally greater than the diameter D, greater than D/2, greater than D/3, etc. 
     In the illustrated embodiment, each lower array  3401  includes a rearward array  3420  opening for supporting the rearward support  2410  in the first configuration (e.g., by the array of fasteners  2480 ). The rearward array  3420  optionally includes a plurality of openings  3422  arranged in a generally polygonal (e.g., rectangular) arrangement. The rearward array  3420  optionally includes an inner opening  3424 . 
     In the illustrated embodiment, each lower array  3401  includes a forward array  3440  opening for supporting the forward support  2420  in the first configuration (e.g., by the array of fasteners  2490 ). The forward array  3440  optionally includes a plurality of openings  3442  (e.g.,  3442   a ,  3442   b ,  3442   c ,  3442   d ) arranged in a generally polygonal (e.g., irregular rectangular) arrangement. The forward array  3440  optionally includes an inner opening  3444 . 
     In the illustrated embodiment, each upper array  3402  includes a rearward array  3410  opening for supporting the rearward support  2410  in the second configuration (e.g., by the array of fasteners  2480 ). The rearward array  3410  optionally includes a plurality of openings  3412  arranged in a generally polygonal (e.g., rectangular) arrangement. The rearward array  3410  optionally includes an inner opening  3414 . 
     In the illustrated embodiment, each upper array  3402  includes a forward array  3430  opening for supporting the forward support  2420  in the second configuration (e.g., by the array of fasteners  2490 ). The forward array  3430  optionally includes a plurality of openings  3432  (e.g.,  3432   a ,  3432   b ,  3432   c ,  3432   d ) arranged in a generally polygonal (e.g., irregular rectangular) arrangement. The forward array  3430  optionally includes an inner opening  3434 . 
     In some embodiments, the offset position of openings  3442   c  and  3432   c  (or in other embodiments the offset position of other openings or other mounting features) causes the arrays  3440 ,  3430  to have an irregular polygonal (e.g., irregular rectangular) arrangement. In the illustrated embodiment, the offset position of the openings  3442   c ,  3432   c  avoids overlap and/or separation by less than the threshold distance between the openings  3432   c  and  3442   a . Other configurations (e.g., irregular polygonal configurations) of the arrays of openings are possible in order to avoid overlap and/or less-than-threshold separation of individual openings in the upper and lower arrays  3401 ,  3402 . 
     Referring to  FIGS. 4 and 9 , in some embodiments side bars  2246 - 1 ,  2246 - 2  are mounted to the sidewalls  2210 ,  2220 , respectively. The side bars  2246  are optionally disposed to the side of the classifier  2300 . The side bars  2246  optionally extend generally parallel to the classifier  2300 . The side bars  2246  optionally comprise upward-facing contact surfaces. The side bars  2246  are optionally made from a metal such as abrasion-resistant steel. The side bars  2246  are optionally mounted to respective sidewalls by mounting plates  2247  (e.g., vertical mounting plates removably fastened to each sidewall). The mounting plates  2247  optionally support side bars  2246  by angle supports  2249  (e.g., angle plates or angle brackets). 
     The side bars  2246  are optionally removably mounted to the sidewalls  2210 ,  2220  (e.g., by fasteners such as nut-and-bolt combinations) such that the side bars may be adjusted between a first configuration (e.g., generally parallel to the first configuration of the classifier  2300 ) and a second configuration (e.g., generally parallel to the second configuration of the classifier  2300 ). 
     Referring to  FIGS. 11 and 12 , each sidewall  2210 ,  2220  optionally includes an array of openings  3340  (e.g., a generally linearly arranged array as illustrated) having a plurality of openings  3342  (e.g.,  3342   a ,  3342   b ,  3342   c ,  3342   d ,  3342   e ) for supporting the side bar  2246  in the first configuration. Each array of openings  3340  optionally extends generally parallel to the first configuration of the classifier  2300 . 
     Referring to  FIGS. 11 and 12 , each sidewall  2210 ,  2220  optionally includes an array of openings  3330  (e.g., a generally linearly arranged array as illustrated) having a plurality of openings  3332  (e.g.,  3342   a ,  3342   b ,  3342   c ,  3342   d ,  3342   e ) for supporting the side bar  2246  in the second configuration. Each array of openings  3330  optionally extends generally parallel to the second configuration of the classifier  2300 . 
     Referring to  FIGS. 2 and 4 , side liners are optionally removably mounted to each of the sidewalls  2210 ,  2220  and positioned adjacent to the classifier  2300 . The side liners optionally protect the sidewalls  2210 ,  2220  from contact with aggregate material bouncing on the classifier  2300 . The side liners may be made of wear-resistant material such as abrasion-resistant steel. The side liners may comprise plates of such material as illustrated. 
     The side liners are optionally modifiable or replaceable when changing the position of the side bars  2246  and/or classifier  2300 . Comparing  FIGS. 2 and 4 , a first side liner  2243  ( 2243 - 2 ) is optionally removably mounted to each sidewall when the classifier  2300  is in the first configuration and a second side liner  2245  is optionally removably mounted to each sidewall when the classifier  2300  is in the second configuration. Each side liner  2243 ,  2245  optionally substantially covers a vertical portion of the associated sidewall disposed above the classifier  2300 . In other embodiments, an additional side liner portion (e.g., triangular portion) is optionally added in the first configuration and removed in the second configuration. 
     Referring to  FIG. 12 , an array of openings  3300  is optionally provided in each side wall to support the side liners. The array  3300  optionally includes a first array  3310  and a second array  3320 . The first array  3310  optionally includes a plurality of openings  3312  (e.g.,  3312   a ,  3312   b ,  3312   c ,  3312   d ). A second array of openings  3320  is optionally provided in each side wall to support the second side liner  2245 . The second array  3320  optionally includes a plurality of openings  3322  (e.g.,  3222   a ,  3322   b ,  3322   c ). The second array  3320  may be disposed below the first array  3310  as illustrated. The second array  3320  may be disposed at an angle to a horizontal as illustrated (e.g., generally parallel to the classifier  2300  in the first configuration). 
     Referring to  FIGS. 13 and 14 , an alternative embodiment of a vibratory feeder  4200  is illustrated. The vibratory feeder  4200  is optionally generally similar to the vibratory feeder  4200 , except that the vibratory feeder  4200  optionally comprises a grizzly classifier having a modified forward support and sidewalls as described below. 
     The vibratory feeder  4200  optionally comprises support  4400  including a modified forward support  4420  having an array of fasteners  4490  optionally arranged in a parallelogram (e.g., slanted parallelogram, oblique parallelogram, etc.) arrangement. The fasteners  4490  optionally extend through a modified forward mounting plate  4422 . 
     The sidewalls (e.g., sidewall  4220 ) of the vibratory feeder  4200  optionally include a plurality of modified forward arrays of openings corresponding to the array of fasteners  4490 . Referring to  FIG. 14 , a first forward array  4430  of openings  4432  (e.g.,  4432   a ,  4432   b ,  4432   c ,  4432   d ) is optionally disposed to support the forward support  4420  so that the grizzly classifier is in a first orientation (e.g., generally horizontal, at about 0 degrees below horizontal, etc.). A second forward array  4440  of openings  4442  (e.g.,  4442   a ,  4442   b ,  4442   c ,  4442   d ) is optionally disposed to support the forward support  4420  so that the grizzly classifier is in a second orientation (e.g., at 5 degrees below horizontal, at about 5 degrees below horizontal, at less than 10 degrees below horizontal, etc.). Each of the first and second forward arrays  4430 ,  4440  are optionally arranged in a parallelogram (e.g., slanted parallelogram, oblique parallelogram, etc.) arrangement. The fasteners  4490  optionally extend through the openings  4432  in the first orientation and optionally extend through the openings  4442  in the second orientation. 
     In some alternative vibratory feeder embodiments, multiple grizzly bar classifiers are incorporated. For example, two, three or more grizzly may be disposed in vertically stacked or stair-stepped relation. In various embodiments, one or more of such classifiers may be adjustably mounted as described elsewhere herein. 
     In some alternative vibratory feeder embodiments (and/or other classifier embodiments), one or more classifying decks being adjustably-mounted as described herein comprise differently-configured grizzly bars (e.g., with or without contact portions, having round or other cross-sections, etc.), other types of sorting or classifying bars, classifying media such as plastic or metal screens, etc. 
     In some vibratory feeder embodiments, material exits the feeder through an opening such as a hole disposed in a bottom end of the feeder rather than through an open end of the feeder. 
     In some vibratory feeder embodiments, the feeder is supported from above such as on cables or other support structure. 
     In some vibratory feeder embodiments, mounting holes (or other attachment structure) are provided in an inner wall (or other structure) separate from the feeder sidewalls for mounting a grizzly bar classifier in two or more configurations. The inner wall (or other structure) is optionally supported on the sidewalls. 
     In some vibratory feeder embodiments, mounting holes (or other attachment structure) are provided in left and right mounting plates (or other structure) independently moveable relative to a sidewall of the feeder. A grizzly bar classifier is mounted to the left and right mounting plates, which are adjustably mounted by sidewall mount fasteners to the left and right sidewalls (or other structure) by one or more fasteners. For example, a sidewall mount fastener may be inserted in one or more openings in the sidewall or in an arcuate slot in the sidewall for adjustment of the mounting plates and grizzly bar classifier between a plurality of configurations (e.g., a horizontal configuration and one or more sloped configurations). 
     In some embodiments, at least a portion of the surface  2240  is curved (e.g., forming a trough-shaped surface) or sloped along a longitudinal (e.g., along direction T) or transverse direction. In some embodiments, the surface  2240  may be omitted such that aggregate material is received directly on a grizzly classifier or other component. 
     In some embodiments, a grizzly bar classifier (e.g., a laterally-extending support thereof such as a rearward support) is pivotally coupled (e.g., by bearings or other structure) to one or more sidewalls of the vibratory feeder. In some embodiments, an actuator such as a hydraulic cylinder is used to modify an orientation of the grizzly bar classifier. 
     Spring Suspension Embodiments 
     Referring to  FIG. 10 , each of the sidewalls  2210 ,  2220  of the feeder  2200  optionally includes a spring suspension system  2270 - 1 ,  2270 - 2 , respectively. 
     The spring suspension may include one or more springs  2272  (e.g.,  2272   a ,  2272   b ) resiliently supporting a generally horizontal plate  2273  as illustrated. The horizontal plate  2273  may removably support (e.g., by fasteners such as bolts) a spring support  2278  which optionally includes downwardly-extending cylinders (not shown) or other features for holding the springs  2272  in position. The horizontal plate  2273  is optionally mounted (e.g., by welding) to the associated sidewall of the feeder. The horizontal plate is also optionally mounted (e.g., by welding) to one or more side support plates  2274  (e.g.,  2274   a ,  2274   b ). The side support plates  2274  are optionally mounted (e.g., by welding) to the associated sidewall. In the illustrated embodiment, the side support plates  2274  extend substantially along a height of the sidewall (e.g., from a lower lip  2214  to an upper lip  2212  of the sidewall  2210 ). An additional angle support  2277  (e.g., angle plate) may additionally be mounted (e.g., welded) to both the horizontal plate  2273  and to the sidewall. 
     A support assembly  1260  is optionally adjustably mounted to at least one of the side support plates  2274 . The support assembly  1260  optionally includes a support surface  1264  (e.g., a horizontal plate as illustrated) which is optionally sized and configured to support at least a portion of the weight of the feeder  2200  on a lifting device (e.g., lift jack) disposed between the support surface and a base such as a base member or the ground. The support surface  1264  optionally extends away from the spring suspension system  2270  (and/or from the sidewall) such that an open space is disposed vertically between the support surface  1264  and the base member (and/or the ground). The open space is optionally sized to receive at least a portion of the lifting device (e.g., lift jack). 
     In some embodiments, the support surface  1264  is optionally formed as a part with ot or otherwise joined to an angle bracket  1266  which is removably fastened (e.g., by bolts  1268 ) to the side support plate  2274 ). In some embodiments, the support assembly  1260  additionally includes one or more plates  1262  mounted (e.g., by welding) to the support surface  1264  and/or the angle bracket  1266  for strengthening the angle bracket and/or the support surface  1264 . 
     In some embodiments, the support assembly  1260  is adjustable. For example, the height of the support surface  1264  may be adjustable by selecting which of an array of vertically spaced holes  2275  in side support plates  2274  to which to fix the support assembly  1260  to the sidewall (e.g., using removable bolts  1268 ). The support assembly  1260  may also have two or more orientations (e.g., a first orientation and a second orientation vertically flipped from the first orientation); in a first orientation (e.g., the orientation illustrated in  FIG. 10 ), the support surface  1262  is optionally disposed higher relative to the base member (and/or the ground) than in the second orientation (e.g., an orientation vertically flipped from that illustrated in  FIG. 10 ). The support surface  1264  is optionally disposed to provide a support surface for the lifting device (e.g., is disposed generally horizontally) in both the first and second orientations. 
     In some embodiments, a maximum height to which the support surface  1264  may be adjusted relative to an upper surface base member is approximately equal to a height of one of the springs of the spring suspension system  2270 . The maximum height of the support surface  1264  relative to the ground may be approximately twice the height of the spring and/or approximately equal to the height of the spring plus a height of the base member. 
     In some embodiments, the support assembly  1260  and corresponding adjustable mounting structure described above may be mounted to other portions of the spring suspension system  2270  or to other structure on the feeder  2200  such as the sidewalls thereof. 
     Although specific embodiments have been illustrated and described, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the disclosure. This application is intended to cover any adaptations or variations of the specific embodiments of the support structures described herein. Therefore, it is intended that the specification is exemplary in nature, and that the scope of the invention is solely defined by the claims the equivalents thereof. For example, any feature described for one embodiment may be used with any other embodiment.