Abstract:
Apparatus for stacking sticks of split-firewood has a drum with interior flights as well as a ramp and chute which do not rotate with the drum. The flights partition the inside wall of the drum into a procession of shelves and pockets. Each shelf extends radially between the drum sidewall and an inner edge. The ramp is mounted inside the drum and has an axially extending upper edge disposed to be spaced by a small gap from the shelf edges at about 9 o&#39;clock relative clockwise rotation of the drum. The chute is also mounted partly inside the drum slopes from a top to a discharge end. The chute is mounted relative to the ramp to form a catch zone for sticks sliding off the ramp inside the drum. The chute furthermore extends outside the drum to discharge sticks of split firewood in neat stacks there.

Description:
CROSS-REFERENCE TO PROVISIONAL APPLICATION(S) 
     This application claims the benefit of U.S. Provisional Application No. 61/396,242, filed May 24, 2011. 
    
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
     The invention relates to a machine for stacking split firewood and, more particularly, to a machine for accepting an input of randomly-oriented sticks of split-firewood and outputting neat stacks or bundles thereof. The output of such a split-firewood stacking machine can thereafter be inputted to, for example and without limitation, a bundling machine (not shown) as for wrapping the bundle of stacked sticks with shrink wrap or the like for further transit in commerce in that form. 
     A number of additional features and objects will be apparent in connection with the following discussion of the drawings and preferred embodiment(s) and example(s). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       There are shown in the drawings certain exemplary embodiments of the invention as presently preferred. It should be understood that the invention is not limited to the embodiments disclosed as examples, and is capable of variation within the scope of the appended claims. In the drawings, 
         FIG. 1  is a perspective view of a machine in accordance with the invention for stacking split firewood; 
         FIG. 2  is an elevational section view taken through line II-II in  FIG. 1 ; 
         FIG. 3  is an enlarged-scale section view of detail in  FIG. 2 ; and 
         FIG. 4  is a section view comparable to  FIG. 3  except showing the ramp flip up in order to avoid damage. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIGS. 1 and 2  shows the ‘front’ of a split-firewood stacking machine  20  in accordance with the invention. While referred to herein as the ‘front’ end, this end is more accurately the output end. 
     The split-firewood stacking machine  20  comprises a fixed base  22  carrying a frame drum  24  for rotation about a horizontal axis. The frame drum  24  comprises front and back annular frames  24  and  26  that have about a six foot ( ˜ 1.8 m) inner diameter and about a seven and one-half foot ( ˜ 2.3 m) outer diameter. The drum  24  is spun by a drive system  30  which is powered by an electric motor  32  mounted on the ‘right’ side of the base  22  (eg., ‘right’ according to the perspective of  FIG. 2 ). 
     As  FIG. 1  shows better, the drum  24  comprises a sidewall  34  that stretches between the front and back annular frames  24  and  26 . As  FIG. 2  shows better, the drum sidewall  34  has a repetitious series of flights  40  attached to it. The sidewall  34  together with the flights  40  resemble an internal ring gear. The front and back annular frames  24  and  26 , the sidewall  34 , and flights  40  turn in unison about a the generally horizontal rotation axis. 
       FIG. 2  also shows better the drive system  30  for the drum  24 . The drum  24  floats on left and rights sets of a front and back pair of spaced idler tires  42  (only the front tire of each of the left and right sets shown in view in  FIG. 2 , wherein the rear tires are hidden from view immediately behind the front tires). These tires  42  may comprise inflatable wheelbarrow tires or the like. The left and right sets of tires  42  are in rolling contact against the drum  24  at about the eight o&#39;clock position and four o&#39;clock position, respectively. The electric motor  32  turns a gear box (not shown) which reduces the input spin speed of the electric motor  32  to a relatively slow output speed for a drive pulley  44 . The drive pulley  44  drives a drive belt  46  which is looped around the outside of the drum sidewall  34 . Hence the electric motor  32  powers the spinning of the drum  24 . To date, the preferred operational speed is just a few rotations per minute. 
     Referring again to  FIGS. 1 and 2  together, split-firewood stacking machine  20  in accordance with the invention further comprises a front and back cover  50  and  52 , a ramp  54  as well as a chute  56 , all which do not rotate with the drum  24 . 
     The drum sidewall  34  has an axial span (ie., the measure between the front and back frames  24  and  26 ) which is chosen according to the length of the sticks  60  the drum  24  is intended to handle. Nominal stick lengths of split firewood can vary according to end use, and, typically vary between twelve inches ( − 0.1 m) and thirty-six inches ( − 1 m) in length. The axial span of this drum sidewall  34  is sized (for sake of a non-limiting example) to tumble sticks  60  of split firewood that are nominally sixteen inches ( ˜ 0.13 m) in length. Hence the axial span of the drum sidewall  34  will be designed to handle slightly over-sized sticks  60 , and might be given an axial span of between seventeen and eighteen inches ( − 0.14 and 0.15 m). 
       FIGS. 3 and 4  are close-up view of what is shown in  FIG. 2 , except on an enlarged scale.  FIGS. 3 and 4  prominently shows the ramp  54  and several of the flights  40  of the drum  24 . The inside of the drum sidewall  34  is studded with an endless succession of these flights  40 . One exemplary, non-limiting design for the flights  40  is to make them out of folded sheet metal (or light gauge plate steel). Another exemplary, non-limiting design for the flights  40  is to make each one individually, and then fasten the flights  40  to the drum sidewall  34  in head to tail fashion to give the appearance of an endless ring. 
     Each flight  40  comprises an abbreviated shelf portion  62  joined to an elongated apron portion  64 , which together are flanked by a diminutive leading flange  66  and a counter-part diminutive trailing flange  67 . The diminutive flanges  66  and  67  provide relatively thin strips of axially-extending material in which to run a series of fasteners (not shown). The fasteners fasten the flights  40  to the sidewall  34 . In a prototype of machine  20  in accordance with the invention, the drum sidewall  34  was produced of rolled plywood. The fasteners comprised wood screws. 
     The flights  40  are fastened to the sidewall  34  in such head-to-tail fashion that the leading flange  66  of any given flight  40  essentially abuts against the trailing flange  67  of the flight  40  ahead of it. 
     Hence the flanges  66  and  67  more or less merge into a seamless unit. Again, the flights  40  are affixed to the drum sidewall  34 , ‘head-to-tail’ so to speak. The leading flange  66  of one flight  40  is nearly abutted right up to the trailing flange  66  of the flight  40  ahead of it, and so on all the way around the drum sidewall  34 . 
     More particularly, each flight  40  comprises the sheet-metal leading flange  66 , which transitions into the sheet-metal shelf portion  62  at a first fold line, which transitions into the sheet-metal apron portion  64  at a second fold line, which transitions into the trailing flange  67  at a third fold line. 
     Two such flights  40  form a pocket  70 . The pocket  70  is characterized by one shelf portion  62  (which is from a following flight  40 ), one apron portion  64  (which is from the flight  40  ahead of the following flight  40 ), and a pocket outer wall  66 - 67  (which is the merger of the leading and trailing flange  66  and  67 , respectively, of the following flight  40  and flight  40  ahead of the following flight  40 ). 
     In use, a jumble of sticks  60  of split firewood are fed into the open bottom of the turning drum  24 . For example, the sticks  60  might be fed by a conveyor  72  into the input end of the open drum  24 , to fall in a heap in the bottom of the drum  24 . The pocket  70  serves to scoop out and lift a (presumably single) stick  60  of split firewood from the tumbling heap in the bottom of the drum  24 . The apron portion  64  serves as a slide for sending sticks  60  into the pocket  70 . When the pocket  70  rotates from the seven o&#39;clock position on toward the eight o&#39;clock position, the stick  60  transfers from resting predominantly on the pocket outer wall  66 - 67  to predominantly on the shelf portion  62 . 
     The shelves  62  of six such flights  40  are in view in  FIG. 3 , one of which is above the elevation of the ramp  54 , another which is about level with an upper edge  74  of the ramp  54  (and there are four more flights  40  below those two flights  40  as well in  FIG. 3 , but the rest are outside the view). 
     For the shelf  62  about level with the upper edge  74  of the ramp  54 , this shelf  62  is indeed carrying one stick  60  of split firewood. It is a non-exclusive design preference that the shelf width is intentionally designed to be wide enough to steadily carry just one stick  60  of split firewood thereon, and not two. If a second stick  60  would try to hang on the very edge of a shelf  62 , the shelf  62  is narrow enough such that the second stick  60  would fall off and slide down the apron  64  before the shelf  62  ever ascended above the elevation of the ramp  54 . Indeed, it would be preferred if the upper edge  74  of the ramp  54  would be the final insurance to ensure one stick  60  per shelf  62 , and scrape off any second sticks  60  that are managing to hang on. 
     In  FIG. 3 , the flights  40  travel up in this view. The shelf  62  about level with the upper edge  74  of the ramp  54  has carried one stick  60  of firewood to about the nine o&#39;clock position. As that flight  40  travels upward to the about the ten o&#39;clock position, it will rotate above the elevation of the upper edge  74  of the ramp  54 , and its shelf  62  will begin to tip at a continually steepening angle. Eventually, that one stick  60  of firewood will slide off the shelf  62  and land on the ramp  54  (as shown). 
       FIG. 3  shows that the flight  40  below the elevation of the ramp  54  is also loaded with one stick  60  of firewood. The shelf  62  of that flight  40  is indexed to about the eight o&#39;clock position. Indeed, that stick  60  of firewood has to travel through an arc behind the upper end of the ramp  54 . That stick  60  is still safely nestled on the shelf  62  and against the pocket outer wall  66 - 67 , and shall safely remain there until the shelf  62  indexes to the ten o&#39;clock position or higher. 
       FIG. 4  shows how the upper edge  74  of the ramp  54  tends to enforce the operational preference for one stick  60  per pocket  70 . Experience has taught that, as these shelves  62  swing through the eight o&#39;clock position to the ten o&#39;clock position (and behind the upper edge  74  of the ramp  54 ), now and then, a stick  60  of firewood gets jammed against the upper edge  74  of the ramp  54 . 
     Typically this happens when two sticks  60  which are just a little thinner than the general population of sticks  60  manage to be scooped up in one pocket  70  after all. 
     The outer stick  60  typically extends off the shelf  62  to such an extent as to jam into the ramp  54  from the underside of the upper edge  74  (as shown). 
     Alternatively, a single stick  60  might every now and then ride on a shelf  62  in an askew orientation. During test trials, the upper edge  74  of the ramp  54  was fixed. An askew stick  60  of firewood could almost pop the ramp  54  off at the upper edge  74  thereof. Hence  FIG. 4  shows one design solution to this discovery. Now, the upper edge  74  of the ramp  54  is no longer fixed but biased by a spring  76  to pivot about a pivot pin  78  to tip up safely out of the way of an askew stick  60  of firewood. 
       FIG. 3  shows that the stick  60  dumped off the shelf  62  in the now near ten o&#39;clock position has by this time slid down the ramp  54  and is proceeding to land in the chute  56 .  FIG. 1  shows the front and back covers  50  and  52  of the machine  20  assembled in place. These covers  50  and  52  are half circles and cover the left half of the front and back open ends of the machine  20 . The drum  24  turns such that its flights  40  orbit its horizontal spin axis. The left half of the orbit can be reckoned as the up run, the right half as the down or return run. The flights  40  predominantly do the work of carrying sticks  60  of firewood between about the five o&#39;clock position to the ten o&#39;clock position. 
     The back cover  52  preferably comprises a ‘solid’ half circle. In contrast, preferably the front cover  50  has a discharge opening  82  through it in its lower half, and out protrudes an extension of the chute  56 . 
     Pause can be taken now to consider use of the machine  20 .  FIG. 1  shows the feed conveyor  72  feeding a supply of randomly-oriented sticks  60  of split firewood for dumping into the bottom of the drum  24 . The sticks  60  land in heaps or piles and the like in the bottom of the drum  24 , such that the separate sticks  60  land in random orientations. 
     It is preferred to load the drum  24  with sticks  60  such that a bottom quarter of the drum  24  (eg., from about the five o&#39;clock position to about the eight o&#39;clock position) is covered with a heap of sticks  60 . The flights  40  continually pass under the pile or heap of sticks  60 . 
     As a flight  40  climbs out from under the pile of sticks  60 , somewhere where its shelf  62  is at about the eight o&#39;clock position, the flight  40  should emerge free with a single stick  60  scooped up on its shelf  62 , and as shown better by  FIG. 3 . Again,  FIG. 3  shows that, the flights  40  which have emerged out from under the pile at about the eight o&#39;clock position do indeed have one stick  60  apiece scooped up on each&#39;s shelf  62 . 
       FIG. 3  furthermore shows that, every time a flight  40  loaded with a stick  60  of firewood orbits past the nine o&#39;clock position and to about the ten o&#39;clock position, it dumps its load of the single stick  60  onto the ramp  54 . The stick  60  might slide one end first, or laterally. Either way, the stick  60  drops into the crosswise chute  56 . The chute  56  has a generally U-shaped cross-section. If the stick  60  successfully lands in the crosswise chute  56 , the stick  60  then orients itself, sliding one end first down the trough of the chute  56 . 
       FIG. 1  shows one stick  60  sliding one end first down the chute  56 &#39;s extension through the front cover  50 . The stick  60  is oriented in the intended orientation for it, and as according to design.  FIG. 1  also shows that an earlier stick  60  has landed to rest in a collection bin  84  for it at the end of the chute  56  extension. Preferably, the bin  84  is indexed back and forth left and right by an outflow conveyor  86  to catch the sticks  60  in a neat stack. Additionally, the bin  84  might be vertically indexed as well to further ensure neat stacking (this is not shown). Alternatively, the sticks  60  might be stacked on end in a five gallon bucket or the like (as shown in the priority provisional application, but not in the drawings here). Preferably, once such a stack has been collected, such a stack can be advanced to a bundling machine  20  or the like (not shown) as for wrapping the bundle of neatly stacked sticks  60  in shrink wrap or the like for shipping in commerce in that form. 
     The invention having been disclosed in connection with the foregoing variations and examples, additional variations will now be apparent to persons skilled in the art. The invention is not intended to be limited to the variations specifically mentioned, and accordingly reference should be made to the appended claims rather than the foregoing discussion of preferred examples, to assess the scope of the invention in which exclusive rights are claimed.