Abstract:
A generally horizontal wood comminuter has a crosswise rotor with comminuting knives moving in a path of rotation and a crosswise coacting anvil. A feed works provides a material support surface and a power-driven feed member above it for feeding material toward the rotor. The rotor is driven in an uphill path of rotation relative to the feed works. Lift arms pivotally carry the feed member for swinging vertical movement toward and away from the material support surface. A crosswise deflector plate is carried independently of the lift arms and extends toward the anvil and a crosswise lift arm plate coacts with the deflector plate to contain fragmented material. The anvil and a grate retainer preferably are pivotal to move together from an operative to an inoperative position. A torque limiting device controls the drive of the rotor.

Description:
This application is a division of U.S. application Ser. No. 09/716,532 filed Nov. 20, 2000, now U.S. Pat. No. 6,474,579. 
     This application claims the priority of provisional application Ser. No. 60/170,043 filed Dec. 10, 1999, which is identically entitled. This invention relates particularly to machines known commercially as “wood hogs” for recycling heavy wood material, such as old railroad ties, the heavy pallets used widely in industry, the structural timbers which remain from the demolition of old buildings, heavy wood scrap, and many other such items. Horizontally fed machines of this character are in wide use and a machine of this type is the subject of U.S. Pat. Nos. 4,771,953 and 5,713,525, which are owned by the applicant&#39;s assignee and are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     It is to be understood that machines of this general character, which are in wide use today for recycling heavy wood products particularly, are of a portable nature in the sense that they can be drawn by tractors or may be self-propelled, can weigh up to 100,000 pounds, and may be up to 50 feet in overall length. Normally such machines, which employ heavy knifed hammers to demolish the wood, are powered by heavy duty diesel engines providing as much as 800-1,000 horsepower. 
     SUMMARY OF THE INVENTION 
     The present wood processing system incorporates a rotary drum having a plurality of peripherally supported comminuting members or hammers. Both uphill and downhill rotors are known and in use, and the machine depicted is an uphill rotor machine in which the rotor moves the material upwardly with respect to the horizontal feed of the material. An anvil is supported near the upper end of the machine just upstream of a grating system which facilitates easy maintenance and the ready changing of grates to provide a considerable selection of grate opening sizes and configurations. The material feed system includes a compression feed drum associated with a horizontal conveyor at the entrance to the comminuting drum or rotor and both are driven in a direction to move material to the comminuting drum. The present invention is concerned with various improvements in machines of this character. One of these involves the use of the downwardly swinging compression feed roll to facilitate upward swinging movement of the anvil and upper grate retainer member for maintenance and clearing purposes. 
     Another improvement is concerned with utilizing a comminuting drum shaft release system which prevents foreign objects, such as heavy metal bolts and fragments from damaging the machine. Still another improvement is concerned with the general construction of the machine including the stacked mounting of the comminuting drum drive shaft and the pivot shaft for the compression feed roll, and a top wall containment deflector plate which is separate from the compression feed roll assembly and pivots with the anvil. 
     A prime object of the present invention is to provide a rugged heavy duty machine, which can be economically operated at chosen locations, which might be at a landfill, or in the field at a demolition site. 
     A further object of the invention is to provide a safer machine which confines the material and does not throw it out in the manner that so-called horizontal tub grinders do. 
     A still further object of the invention is to provide a machine which is particularly designed to handle heavy waste wood material in an effective manner, while, at the same time, being so constructed as to be capable of being economically manufactured and sold at an economically attractive price. 
     Other object and advantages of the invention will become apparent with reference to the accompanying drawings and the accompanying descriptive matter. 
    
    
     GENERAL DESCRIPTION OF THE DRAWINGS 
     The presently preferred embodiment of the invention is disclosed in the following description and in the accompanying drawings, wherein: 
     FIG. 1 is a schematic side elevational view of the machine with part of the near side wall broken away to show elements of the machine; 
     FIG. 2 is a partly sectional fragmentary schematic side elevational interior view on an enlarged scale showing the feed drum in down position; 
     FIG. 3 is a similar view with the feed drum in raised position and with certain components omitted from the view for the sake of clarity; 
     FIG. 4 is a still further enlarged fragmentary side elevational view of the comminuting drum and drum grate system only; 
     FIG. 5 is a greatly enlarged side elevational view of a portion of the grate and grate retainer system only; 
     FIG. 6 is a view similar to FIG. 3 with the cylinder for lifting the upper grate retainer hood reconnected to the hood; 
     FIG. 7 is a partly sectional fragmentary schematic view similar to FIG. 6, but showing the feed drum in down position and the upper grate retainer hood raised, certain components being missing from the view; 
     FIG. 8 is a similar schematic partly sectional fragmentary side elevational view illustrating elements used in the changing of the grate; 
     FIG. 9 is a side elevational view of one of the lower grate holder arms only; 
     FIG. 10 is a partly sectional top plan view of the comminuting drum drive shaft assembly only; 
     FIG. 11 is an enlarged sectional end elevational view showing the drive members in engaged driving position; and 
     FIG. 12 is a similar view showing the drive members in disengaged position. 
    
    
     DETAILED DESCRIPTION 
     Referring now, more particularly, to the accompanying drawings wherein a presently preferred embodiment of the invention is disclosed and directing attention initially to FIGS. 1 and 2, a letter M generally designates the wood processing machine which is shown as mounted on a trailer frame F which may be readily towed to the site of use, and which has a tow coupling mounted on one of its ends to facilitate coupling the machine to a towing vehicle. The trailer or machine frame F includes longitudinal channels or beams  10  and  10   a  connected by suitable cross beams or the like  11  at spaced intervals along the length of the machine. Wheels  12 , with tires  13  thereon, are journaled on axles  14  carried by the frame F and vertically adjustable columns  15 , with ground engaging pivotable plates  15   a  thereon, are movable in casings  16  secured to the frame F from a retracted position to an extended lowered position in which the support columns  15 , in conjunction with the wheels  12 , support the machine for operation in generally horizontal disposition. 
     At the front end of the machine, front and side walls  17  are provided to enclose a wood receiving conveyor system, generally designated C, which includes motor driven longitudinally extending endless chains  18 , traveling over a floor plate  17   a  around front and rear sprockets  19  mounted on shafts  20  jounaled by the frame F. Material supporting, transversely extending bars or plates may be provided to connect the chains  18 . 
     The walls  17  may be braced by suitable vertical stanchions  21 . Upstanding side walls  22  and  22   a  are provided on the frame F rearwardly of the walls  17  to extend rearwardly therefrom to collectively house a material feed wheel, feed member, or drum, generally designated  23 , and a wood shredding or fragmenting rotor or drum, generally designated  24 . The conveyor  18  and the wheel  23 , operating in conjunction, or either of them singularly, may be aptly termed a “feed works” for feeding material to be comminuted to the rotor drum  24  in a continuous longitudinal stream or flow of waste wood material. 
     The side walls of the machine,  22  and  22   a,  are supported by upper longitudinally extending beam members  22   b,  which connect to the upright side beams  21 . Vertically slotted aligned openings O (FIG. 2) are provided in side walls  22  and  22   a  and vertical shaft and bearing support plates  27  and  28 , which vertically abut at  29  are disposed in alignment with the openings O interiorly thereof. The lower plates  28 , in FIG. 2, carry the comminuting drum drive shaft  30  and the plates  27  carry the feed drum pivot shaft  31  in a state of vertical alignment. Once the shafts  30  and  31  are inserted through the openings O at each side of the machine when plates  27  and  28  are lowered into position, the ends of the shaft  30  may be captured by shaft journaling bearings, generally designated  32 , which comprise a lower half  33  supported on plates  34  and  35  carried by the side walls  22  and  22   a  of the machine M and upper bearing parts  36  which bolt to the lower bearing parts  33  as at  36   a.  Vertical retainer bars  26  and  26   a  bolt over the plates  27  and  28  to the side walls  22  and  22   a  to secure the plates  27  and  28  in fixed position. Suitable bearings (not shown) are also provided to journal shaft  31 . 
     The feed drum  23  is shown in lowered position in FIG.  2  and in raised position in FIG.  3 . Feed drum side plate assemblies, generally designated  38 , connected by arm portions or arms  38   a  to laterally spaced bushings  39 , received on shaft  31 , support the shaft  40  of feed drum  23  via bearings  41  provided on the side plate assemblies  38 . The side plate assemblies  38  or support assemblies, which between them carry feed drum or feed member  23 , include curved walls  38   b  and  38   c  which effectively span the arms  38   a  of the assemblies  38  which lie adjacent to side walls  22  and  22   a  and keep wood fragments from entering or leaving the comminuting region along the upper end of the feed drum or feed member  23  when it is in lowered operative position. A curved wall  38   d  connects walls  38   b  and  38   c  which may be referenced as lift arms. An anvil frame or anvil plate assembly AF, to which anvil A is fixed, is stationary when the machine is in operation and also mounts a top containment wall and material deflector plate  37  which normally is in fixed position. The frame AF which includes arms  37   a  fixed to wall  37  is fixed to bushings B which are pivotal on shaft  31  between the bushings  39  to permit anvil frame AF to pivot upwardly thereon when the machine is not in operation. 
     A feed drum shaft  40  (FIG. 2) has drum end plates  42 , forming a part of assemblies  38 , which support wood engaging and driving toothed members  43  constituting a peripheral drum surface as usual, generally designated  44 . A suitable reversible rotary hydraulic motor, generally designated  45 , and supported by one of the side plate assemblies  38  may be coupled to the shaft  40  for purposes of driving it in the direction indicated, or in the opposite direction of rotation. Double acting hydraulic cylinders  46  connected to the side plate assemblies  38  as at  47 , and to a bracket  48  fixed on vertical frame stanchions  49  at  50 , is utilized in moving the drum  23  from the position shown in FIG. 2 to the position in which it is shown in FIG.  3 . 
     The cutting or chipping drum  24 , which is shown as rotated in the uphill direction by the arrow x in FIG. 2, has a rotary drum periphery  51  extending from end to end of the drum  24  which includes a series of cutting teeth or comminuting members  52  in suitably spaced tool holders  53 . For purposes of convenience, only several of the many laterally and circumferentially spaced teeth  52  are shown in the drawings. 
     As FIGS. 2-8 particularly illustrate, the periphery of the cutting drum  24  is partly surrounded by perforate grate members  54 ,  55 ,  56 , and  57  (FIG.  4 ), which, as FIG. 5 shows, are provided with grate openings  58 . These grates  54 - 57 , which all have the openings  58 , extend lengthwisely or axially across the periphery of the drum, and are held in place by a grate retainer mechanism, generally designated  59  (FIGS.  4  and  5 ). The retainer mechanism has holding elements or arms  63  which pivotally mount at  60  to a frame F frame member  61 . The mechanism  59  includes a pair of stationery end tracks  62 , which embrace the ends of the grates  54 - 57  and are supported by frame members  61  upon side walls  22  and  22   a,  or in some other suitable manner. The intermediate clamp arms  63  (FIG.  5 ), which pivotally mount on shaft  60 , are moveable sufficiently peripherally outwardly from the knife drum  54  to permit changing of the grates  54 - 57 . 
     It is to be understood that the grates  54 - 57  are very heavy and typically are handled by a chain hoist device, generally designated  64 , in FIG.  8 . The chain hoist device  64  is moveable on rollers  65  along longitudinal tracks  66 . The chain hoist device  64  is shown in FIG. 8 in the process of lifting an uppermost grate  67  having the same openings  58 . Grate  67  is retained by an upper grate retainer device  74  forming a part of anvil frame AF, but also may be used to lift any of the grates  54 - 57  once the pivotal retainer arms  63  are released and swing outwardly sufficiently to clear the grates for upward sliding removal guided by fixed end supports  62  and curvilinear plates  70   b.    
     Wood chips of the proper and desired size pass through the grate openings  58  and the various grates  54 - 57  and  67 , and are removed by an underneath endless conveyor, generally designated  68 . As shown, the chip take away conveyor  68  includes endless belts  69  trained around pulleys  70  in the usual manner and driven by motors powered by the engine E of the machine. 
     A laterally extending grate support member, generally designated  70   a,  which spans the grate assembly G and bolts to the frame side walls  22  and  22   a,  has blocks  71  with front edges cut away as at  71   a  to accommodate the stepped configuration  63   a  provided on each of the arms  63  (FIG. 9) and function as a stop, limiting radially outward swinging movement of the grate support arms  63 . The curvilinear plates  70   b,  forming a part of the member  70   a,  extend to meet the marginal abutting edges of the grate plates  56  and  57 . The plates  70   b  have triangularly shaped gussets  70   c.  Bolts  171  extending through the blocks  71   b  and threaded through nuts  171   a  are adjustable to engage and hold the arms  63  in grate retaining position. The bolts  171  are backed off when it is desired to release the arms  63  to move outward and rest on nuts  171   a.  The curved plates  70   b  do not exert sufficient pressure on the grates to prevent withdrawal of the grates upwardly and function as grate supports. At their upper ends arms  63  have straps  72 , with flared ends  72   a,  fixed to them for a purpose to be presently described. 
     As noted previously, the system also includes an upper grate  67 , which is in abutting engagement with the plate  57 , and is held in place by the anvil frame housing or hood member  74 , which can be raised outwardly away from the position in which it is shown in FIG. 2 to the position shown in FIG.  7 . It will be seen that a double acting hydraulic cylinder, generally designated  75  and pivotally received on a mount bracket  76  connected to the side plate assembly or housing  38 , has a piston rod  77   a  normally inactively pivotally connected to a mount  78  on assemblies  38 . Anvil frame AF, and hood  74  are mounted for pivotal movement on the shaft  31  by the sleeve or bushing members B, which interleave with the sleeve or bushing members  39  that mount the feed drum assembly  38  pivotally on the shaft  31 . Guide members  72   b  on the hood  74  in alignment with arms  63  are received in and guide on the flared ends  72  on arms  63  when the hood  74  is in grate retaining position. 
     To remove grate retaining hood  74 , the assembly or housing  38  is first moved to the raised position shown in FIG. 3 from the operative position shown in FIG. 2 by the double acting cylinders  46 . When in this raised position, the piston rod  77   a  can be decoupled from the mount  75   a,  extended, and pivotally attached to a bracket  77   b  provided on housing  74  as shown in FIG.  7 . With the system disclosed, lifting of the grate retaining housing or hood  74  is readily accomplished using the weight of the feed drum assembly  23  returning to operative position, the weight of plate  37 , and cylinder  75  with its relocated piston  77   a.  Cylinder  75  later can control the restoration of the housing  74  to the closed grate embracing position when an upper grate  67  is restored to position. With the piston  77   a  in its maximum position of extension, the cylinder  75  and piston rod  77  initially function as a lever connected to the assembly  38  which causes the housing  74  to be initially lifted away from the grate  67  and then complete the final movement to the FIG. 7 position. 
     The shaft  30  extends through one of the side walls  22  and  22   a  to be driven by a belt operated sheave  76  (FIG. 10) via a torque limiter device, generally designated  76   a,  which now will be described. The belt sheave  76  is driven appropriately by belts  76   a  connected with a drive  76   b  operated by the diesel engine E. The torque limiter  76   a  comprises a series of circumferentially spaced torque limiting devices, generally designated  77  (FIG.  11 ), which operate, under normal conditions, to couple a flange  78  keyed to shaft  30  to a flanged part  79  fixed to the sheave  76  but rotatable on shaft  30 . Part  79  incorporates a drive disc  79   b  attached to sheave web  76   b  by bolts  76   c.    
     To understand the operation of the torque limiting devices  77 , attention is directed to FIG. 11 which shows the members  78  and  79  in engaged position and to FIG. 12 which shows them in disengaged position. Each of the six circumferentially spaced torque limiting devices which are utilized includes adjoining fittings  79   a  and  78   a  which are received within normally communicating openings  79   b  and  78   b  provided in the flanges  79  and  78 , respectively. The fitting  79   a  is secured to the flange member  79  by a bolt member  81  and the fitting includes an enlarged recessed portion  82 , which in the engaged (driving) position, receives a portion of a drive ball  83 , which is retained in the bore  84  of the sleeve fitting  78   a.  A slideable plunger  85 , extends into the sleeve fitting  78   a  from a torque limiter end housing portion  86 , and it will be seen that the plunger  85  has an enlarged flange portion  87  inward of a ball accommodating valley or recess  89  with a sloped wall  90 . 
     The plunger  85  is retained axially by means of a system of race forming members  91  and  92  acting on a circle of balls  94 . The members  91  and  92  are loaded by the spring pressure of a spring, such as a coil spring  93 . Screw member  95  threadingly engaged at  96  with the interior of housing bore  86  and alters the spring force as required for the torque limiting operation desired. 
     In a situation in which the cutting drum  24  should become jammed and not be free to rotate with the sheave flange  76   b,  the flange  79  will force each ball  83  to escape its socket  82  and cause each plunger  85  to be forced through each circle of balls  94 , overcoming the spring loading on the angled races  91  and  92 . Thus, the drive motor or engine for rotating the drum and the drum is protected without the necessity of the grates being disengaged when foreign matter is encountered in the wood fed to the machine. Typically for material jams between the grates and the rotating comminuting drum in such horizontally fed machines, the previous solution to the problem has been a disengageable grate which is forced to a disengaged position. 
     In the present machine once the foreign matter has been removed, the resetting of each torque limiter is a simple matter of first aligning the flanges  78  and  79  so that each ball  83  is opposite a cavity  82  and then pushing the plungers  85  toward the flanges  79  to permit each circle of balls  94  to return to original position. It is to be understood that the torque limiter described is a commercially available unit. 
     The Operation 
     In operation, the material to be comminuted is fed from the conveyor chains  18  to a position beneath the feed drum  23 , which is in the position shown in FIG.  3 . It will be raised upwardly as necessitated by the flow of material. The wood is advanced forwardly toward the comminuting drum  24  by the combined forwarding action of the conveyor chains  18  and the feed drum  23 . Material processed forwardly by the conveyor chains and the drum  23  into the path of the teeth  52  on drum  24  is initially fragmented by the teeth  52  and moved upwardly between the drums  22  and  24  where it is contained by the deflecting surface or plate  37  which substantially spans the area between side walls  22  and  22   a  and extends to a position just short of the curvilinear shield  38   c.  With wall  37  remaining in fixed position regardless of the position of the feed drum  23  which moves upwardly and downwardly with the height of material being fed under feed drum  23 , the deflection of material to the also fixed anvil A remains constant and controlled. The moving housing portion  38   c  contains the fragments of materials and deflects them toward plate  37  which directs them to pass beneath anvil A where they are further reduced or comminuted. Thereafter, if they are of sufficient size to pass through the grate openings in the overall grate G, they do so and, of course, the grate assists further fragmentation in view of the limited clearance, i.e. five-eighths of an inch, between the fixed teeth  52  on the rotating drum  24  and the grate G. 
     As indicated should a foreign non-fragmentable body become jammed between the grate G and the drum  24 , the torque limiters will disengage the drive motor from drum  24  which is held stationery by the jammed condition. As indicated earlier, when the jammed condition is relieved and the flanges  78  and  79  restored to the engaged position of peripheral alignment shown in FIG. 11, the plungers  85  may simply be readily pressed inwardly to restore the balls  83  to an engaged position in which torque is transmitted once again to the drum  24 . 
     To obtain access to the front portion of drum  24 , cylinder  46  can be activated to swing the drum  23  from the position shown in FIG. 2 to the raised position shown in FIG.  3 . In this position of the parts, it will be noted that cylinder  75  is inactively connected to bracket  75   a.  To remove the upper grate  67 , which is retained by housing or hood  74 , the piston rod  77   a,  of the cylinder  75 , may be unhooked from brackets  75   a,  power extended, and reattached to bracket  77   b  provided on the hood member  74 . Accordingly, when the cylinders  46  are operated to restore the feed drum  23  to operative position, the weight of this assembly will initially lift the frame AF and relatively heavy housing  74  from the position shown in FIG. 2 to a position in which it is partly removed from the grate  67 , and with this momentum, piston rod  77  can then be retracted to complete the upward swing of retention hood  74 . 
     The chain hoist  64 , traveling on trolley  65 , may then have its hook  64   a  extended through one of the openings in grate  67 , which may then be lifted off as FIG. 8 indicates is occurring. The grate sections  54 - 57  may be removed by sliding them upwardly, once the retainer arm members  63  are released by backing off bolts  71  and swung outwardly to rest the on stepped members provided on member  70   a.  Hooks  64   a,  are also employed, in this further removal of the heavy grate sections. 
     The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims.