Abstract:
A method of arranging sod rolls on a pallet including the steps of using a sod harvester to create a plurality of sod rolls and deposit them onto a platform; rotating all but one of the sod rolls so that an end flap on each of the sod rolls is at the same position; rotating the first sod roll for a duration that is longer than the duration by which the remaining sod rolls are rotated so that an end flap on the first sod roll is in a different position on the first sod roll than the end flaps on the remaining sod rolls; using a sod carrier to pick up the plurality of sod rolls from the platform simultaneously; and depositing the plurality of sod rolls simultaneously onto a pallet such that the end flap on the first sod roll faces outward and is viewable by consumers.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 13/946,956 tiled on Jul. 19, 2013, the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to the field of sod harvesters, and more specifically, to a sod harvester with a flap control device for consistently and neatly rolling pieces of sod so that the end of the flap is situated at roughly the same position on each roll of sod. 
         [0004]    2. Description of the Related Art 
         [0005]    Sod harvesters for cutting strips of sod from the ground, rolling them into sod rolls, and stacking the sod rolls onto pallets have existed for a number of years. Various sod harvester innovations have been patented, several of which relate to the rolling of sod pieces, and at least one of which has attempted to solve the same problem as the present invention. U.S. Pat. No. 7,021,584 discloses a sod roller for automatically controlling the angular position of the end or flap of a roll of sod about the roll. The latter invention differs structurally from the present invention in a number of respects, including, but not limited to, the fact that it utilizes three conveyors rather than two, and it also incorporates a sensor for measuring displacement of the transport conveyor. The transport conveyor sensor is not needed in the present invention. 
         [0006]    When sod is sold at commercial establishments, it is typically stacked several rows high on a pallet. The more neatly the stack appears, the more likely it is to be sold. In addition, neatly stacked rolls are less likely to fell off of the pallet. In both of these respects, the placement of the end of the flap on the sod roll is important. If the end of the flap is located at roughly the same position on each of the sod rolls, this creates a more uniform appearance and adds stability to the overall configuration of the sod rolls. The present invention is designed to ensure that the end of the flap on a roll of sod is situated at roughly the same position on each roll of sod that comes off of the sod harvester. 
         [0007]    Other innovations relating to sod rollers include U.S. Pat. No. 3,790,096 (Brouwer, 1974) (device for starting a two in the end of a sod strip); U.S. Pat. No. 4,142,691 (Watton, 1979) (apparatus tor starting a turn in a strip of sod traveling along a conveyor); U.S. Pat. No. 6,834,729 (Brouwer et al, 2004) (pre-starter for starting a turn in the end of a sod strip travelling up a conveyor); and U.S. Patent Application No. 2001/0050174 (Van Vuuren) (in one embodiment, incorporating a rolling conveyor between the receiving and discharge ends of the conveyor head for purposes of rolling cut grass sods). None of these innovations, however, is concerned with the consistent positioning of the end of the flap on the sod roll. 
       BRIEF SUMMARY OF THE INVENTION 
       [0008]    The present invention is a sod harvester comprising: a start gate; a first switch that is configured to interact with a first sensor; a second switch that is configured to interact with a second sensor; an inclined conveyor with a first end and a second end; and a rollup conveyor positioned above the second end of the inclined conveyor; wherein the first switch is positioned between the start gate and the second switch; wherein the second switch is positioned between the first switch and the rollup conveyor; wherein when the second sensor is activated, the rollup conveyor begins rotating; wherein when the first sensor is activated, an encoder begins measuring distance traveled rotationally by the rollup conveyor; and wherein the rollup conveyor stops rotating when the rollup conveyor has traveled a certain distance rotationally. 
         [0009]    In a preferred embodiment, the first sensor is activated when a trailing edge of a sod piece moves out from underneath a bottom end of the first switch and a top end of the first switch is moved into proximity with the first sensor. Preferably, the second sensor is activated when a piece of sod causes the second switch to change position so that the second switch is moved into proximity with the second sensor. 
         [0010]    In a preferred embodiment, the bottom end of the first switch extends through a front rollup ladder, and the start gate is attached to the front rollup ladder. Preferably, the rollup conveyor is situated within a rear rollup frame. In one embodiment, the second switch is situated on the front rollup ladder. In another embodiment the second switch is situated on the rear rollup frame. 
         [0011]    In yet another embodiment, the invention further comprises a bumper that is secured to a rear of the rear rollup frame, the bumper extending beneath the rollup conveyor along a width, of the rollup conveyor and preventing from over-rotating an end flap on a first sod roll in a plurality of sod rolls that are picked up simultaneously by a sod carrier and deposited, simultaneously onto a pallet, each of the sod rolls in the plurality of sod rolls having an end flap, the end flap on all but the first sod roll in the plurality of sod rolls being at a same position, the end flap on the first sod roll being in a different position, and the end flap on the first sod roll being at a position between nine o&#39;clock and twelve o&#39;clock when the first sod roll is viewed from a side of the first sod roll. 
         [0012]    In a preferred embodiment, the inclined conveyor and the rollup conveyor move at a same speed and in a same direction rotationally. The certain distance measured by the encoder is preferably adjustable by an operator. 
         [0013]    The present invention is also a method of arranging sod rolls on a pallet, the method comprising: using a sod harvester to create a plurality of sod rolls and deposit them onto a platform; as each of the sod rolls is deposited onto the platform, rotating all but one of the sod rolls in the plurality of sod rolls so that an end flap on each of the all but one of the sod rolls in the plurality of sod rolls is at the same position on the sod roll; wherein one of the sod rolls in the plurality of sod rolls is the first sod roll in the plurality of sod rolls to be deposited onto the platform, as the first sod roll is deposited onto the platform, rotating the first sod roll for a duration that is longer than the duration by which the all but one of the sod rolls in the plurality of sod rolls are rotated so that an end flap on the first sod roll is in a different position on the first sod roll, than the end flaps on the all but one of the sod rolls in the plurality of sod rolls, the end Hap on the first sod roll being at a position between nine o&#39;clock twelve o&#39;clock when the first sod roll is viewed from a side of the first sod roll; using a sod carrier to pick up the plurality of sod rolls from the platform simultaneously; and depositing the plurality of sod rolls simultaneously onto a pallet such that the end flap on the first sod roll faces outward and is viewable by consumers. 
         [0014]    In a preferred embodiment, the duration of rotation of the first sod roll is adjustable by an operator via a control screen in a cab of the sod harvester. In another preferred embodiment, the method further comprises using a bumper that is situated over the platform to prevent the end flap on the first sod roll from over-rotating. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0015]      FIG. 1  is a perspective view of a sod harvester with the flap control device of the present invention. 
           [0016]      FIG. 2  is a perspective view of the flap control device of the present invention shown with a sod piece on the inclined conveyor. 
           [0017]      FIG. 3  is the same view shown in  FIG. 2  except that two of the chains, one turn buckle, and the start gate spring have been removed for clarity. 
           [0018]      FIG. 4A  is a top view of the flap control device indicating where the section view of  FIG. 4B  has been taken. 
           [0019]      FIG. 4B  is a side section view of what is shown in  FIG. 3 . 
           [0020]      FIG. 5  is a detail perspective view of the flap control device of the present invention shown with a leading edge of a sod piece in contact with the start gate of the flap control device and beginning to roll. 
           [0021]      FIG. 6  is a side section view of what is shown in  FIG. 5 . 
           [0022]      FIG. 7  is a first detail perspective view perspective view of the flap control device of the present invention shown with the leading (rolled) edge of the sod piece situated under the tail of the first switch and the first sensor in a deactivated position. 
           [0023]      FIG. 8  is a side section view of what is shown in  FIG. 7 . 
           [0024]      FIG. 9  is a second detail perspective view of what is shown in  FIG. 7 . 
           [0025]      FIG. 10A  is a top perspective view of what is shown in  FIG. 7 . 
           [0026]      FIG. 10B  is the same view shown in  FIG. 10A  except that two of the chains, one turn buckle, the start gate spring, and part of the hanging frame have been removed for clarity. 
           [0027]      FIG. 11  is a wider perspective view of what is shown in  FIG. 7 . 
           [0028]      FIG. 12A  is a detail perspective view of the flap control device of the present invention shown with the leading (rolled) edge of the sod piece situated underneath the second switch and the second sensor in an activated position. 
           [0029]      FIG. 12B  is a perspective section view of what is shown in  FIG. 12A . 
           [0030]      FIG. 13  is a side section view of what is shown in  FIG. 12B . 
           [0031]      FIG. 14  is a wider perspective view of what is shown in  FIG. 12A . 
           [0032]      FIG. 15  is a side section view of the flap control device of the present invention shown with the trailing edge of the sod piece no longer situated underneath the tail of the first switch and the first sensor in an activated position. 
           [0033]      FIG. 16  is a perspective view of the flap control device of the present invention shown with the sod roll in a fully rolled position but with the flap not yet located in the preferred position. 
           [0034]      FIG. 17  is a side section view of what is shown in  FIG. 16 . 
           [0035]      FIG. 18  is a side view of the flap control device of the present invention showing two sod rolls on the platform. 
           [0036]      FIG. 19  is a bottom perspective view of the second switch. 
           [0037]      FIG. 20  is a side view of the present invention showing the over-rotation of the end roll in a group of sod rolls. 
           [0038]      FIG. 21  is a detail view of the rubber bumper on the rear end of the rear rollup frame. 
       
    
    
     REFERENCE NUMBERS 
       [0039]      1  Sod harvester 
         [0040]      2  Sod cutting knife 
         [0041]      3  Inclined conveyor 
         [0042]      4  Roll up conveyor 
         [0043]      5  Tension roller 
         [0044]      6  Front rollup ladder 
         [0045]      7  Rear rollup frame 
         [0046]      8  Sod piece 
         [0047]      9  Start gate 
         [0048]      10  Pivot rod 
         [0049]      11  Chain 
         [0050]      11   a  Spring (on start gate) 
         [0051]      11   b  Spring (on first switch) 
         [0052]      12  First switch 
         [0053]      12   a  Bottom end (of first switch) 
         [0054]      12   b  Top end (of first switch) 
         [0055]      13  First sensor 
         [0056]      14  Second switch 
         [0057]      15  Second sensor 
         [0058]      16  Encoder 
         [0059]      17  Hydraulic motor 
         [0060]      18  Platform 
         [0061]      19  Conveyor side rail 
         [0062]      20  Main frame 
         [0063]      21  Hanger frame 
         [0064]      22  Collar (first switch) 
         [0065]      23  Turn buckle 
         [0066]      24  Bolt 
         [0067]      25  Support bracket 
         [0068]      26  Plate 
         [0069]      27  End collar 
         [0070]      28  Collar (second switch) 
         [0071]      29  Rubber bumper 
       DETAILED DESCRIPTION OF INVENTION 
       [0072]      FIG. 1  is a perspective view of a sod harvester with the flap control device of the present invention. As shown in this figure, the sod harvester  1  comprises a sod cutting knife  2 , an inclined conveyor  3 , and a rollup conveyor  4 . The rollup conveyor  4  is situated directly on top of the upper part of the inclined conveyor  3 . The conveyor side rail  19  and main frame  20  have been removed from subsequent figures for clarity. 
         [0073]      FIG. 2  is a first perspective view of the flap control device of the present invention shown with a sod piece on the inclined conveyor.  FIG. 3  is the same view shown in  FIG. 2  except that two of the chains  11 , one turn buckle  23 , and the start gate spring  11   a  have been removed for clarity. In this figure, the sod piece  8  has not yet come into contact with the start gate  9  of the flap control device. As shown in this figure, the flap control device comprises a tension roller  5 , a front rollup ladder  6 , and a rear rollup frame  7 . The tension roller  5  is configured, to ensure that the piece of sod  8  on the inclined conveyor  3  maintains contact with the inclined conveyor  3 . The front rollup ladder  6  comprises a start gate  9  that pivots on two pivot rods  10  on either end of the start gate  9 . 
         [0074]    Note that although turn buckles  23  are shown in the accompanying figures, the present invention is not limited to the use of turn buckles  23  to support the front rollup ladder  6 . Any method of supporting the front rollup ladder  6  may be used. Note also that although two pivot rods  10  are shown, the start gate  9  may pivot on a single pivot rod  10  that extends from one end of the start gate  9  to the other. In addition, the present invention is not limited to the use of chains  11  to suspend the front rollup ladder  6  or the rear rollup frame  7 , nor is it limited to any particular number of chains  11 . 
         [0075]    When a piece of sod  8  moves upward on the inclined conveyor  3 , it first passes underneath the tension roller  5 . Next, the leading edge of the piece of sod  8  comes into contact with the start gate  9 , which causes the piece of sod  8  to being rolling up. A spring  11   a  is used to adjust the tension on the start gate  9 . Note that both the front rollup ladder  6  and the rear rollup frame  7  are preferably suspended by chains  11  so that they can move upward to accommodate the growing sod roll as it passes underneath them. The rollup conveyor  4  is attached to and situated within the rear rollup frame  7  so that it moves upward with the entire rear rollup frame  7 . 
         [0076]    A first switch  12  is attached (welded) to a collar  22  that pivots about a bolt (see  FIG. 9 ). A spring  11   b  attached to the first switch  12  and to the banger frame  21  biases the first switch downward. The bottom end  12   a  of the first switch  12  extends through the front rollup ladder  6  so that it is in a position to come into contact with a piece of sod  8  as it moves up the inclined conveyor  3 . The top end  12   b  of the first switch  12  is configured to interact with a first sensor  13 . A second switch  14  is attached to two end collars  27  that pivot about a bolt  24  (see  FIG. 10B and 12B ); the second switch  14  is configured to interact with a second sensor  15 . The function of the first and second sensors  13 ,  15  is discussed below. Although the first and second sensors  13 ,  15  are depicted as proximity sensors in the drawings, any suitable type of sensor (for example, an optical sensor) may be used. 
         [0077]    The inclined conveyor  3  and rollup conveyor  4  are preferably powered by hydraulic motors  17 . During operation of the sod harvester  1 , the inclined conveyor  3  is in continuous movement whereas the rollup conveyor  4  starts and stops based on the activation or deactivation of the first and second sensors  13 ,  15 , as explained more fully below. When the rollup conveyor  4  is on, it rotates at the same speed and in the same direction as the inclined conveyor  3  (that is, counterclockwise from the perspective of the viewer in  FIG. 4B ). 
         [0078]      FIG. 4A  is a top view of the flap control device indicating where the section view of  FIG. 4B  has been taken.  FIG. 4B  is a side section view of what is shown in  FIG. 3 .  FIG. 4B  shows the relation of the first and second switches  12 ,  14  to the inclined conveyor  3 . 
         [0079]      FIG. 5  is a perspective view of the flap control device of the present invention shown with a leading edge of a sod piece in contact with the start gate of the flap control device and beginning to roll.  FIG. 6  is a side section view of what is shown in FIG.  5 ; the section is taken as indicated in  FIG. 4A . As shown in these two figures, the sod piece  8  starts to form a roll when the leading edge of the sod piece  8  comes into contact with the start gate  9 . The start gate  9  pivots upward on the pivot rods  10  to allow the leading (and beginning to roll) edge of the sod piece  8  to pass through it. Once the sod roll starts to form, the sod piece  8  continues rolling as it moves upward on the inclined conveyor  3 . The front rollup ladder  6  maintains pressure on the forming sod roll so that it stays on the inclined conveyor  3 . 
         [0080]      FIG. 7  is a perspective view of the flap control device of the present invention shown with the leading (rolled) edge of the sod piece situated under the tail of the first switch and the first sensor in a deactivated position. The turn buckle  23  and start gate spring  11   a  have been removed from this figure for clarity.  FIG. 8  is a side section view of what is shown in  FIG. 7 ; the section is taken as indicated in  FIG. 4A . As shown in these two figures, the piece of sod  8  continues to roll (with the roll getting larger) as it makes Its way up the inclined conveyor  3  and underneath the front rollup ladder  6 . As this happens, the bottom end  12   a  of the first switch  12  rises, and the top end  12   b  of the first switch moves away from the first sensor  13 . 
         [0081]      FIG. 9  is a second detail perspective view of what is shown in  FIG. 7 . This view shows that the first switch  12  pivots on a collar  22  that rotates about a bolt  24  in a support bracket  25  that is attached (in this case, bolted) to the underside of the hanger frame  21 .  FIG. 10A  is a top perspective view of what is shown in  FIG. 7 . This particular view shows more clearly how the bottom end  12   a  of the first switch  12  extends through the front rollup ladder  6 .  FIG. 10B  is the same view shown in  FIG. 10A  except that two of the chains  11 , one turn buckle  23 , the start gate spring  11   a , and part of the hanging frame  21  have been removed for clarity.  FIG. 11  is a wider perspective view of what is shown in  FIG. 7 . 
         [0082]    With regard to the first switch, the present invention is not limited to any particular configuration of the first switch, as long as it is positioned between the start gate  9  and the second switch  14 , as long as the top end  12   b  of the first switch  12  is configured to interact with a first sensor  13 , and as long as the first switch  12  is configured so that the bottom end of the first switch  12  extends through the front rollup ladder  6 . 
         [0083]      FIG. 12A  is a detail perspective view of the flap control device of the present invention shown with the leading (rolled) edge of the sod piece situated underneath the second switch and the second sensor in an activated position.  FIG. 12B  is a perspective section view of what is shown in  FIG. 12A ; the section is taken as indicated in  FIG. 4A . In this position, the piece of sod  8  (now a partially formed sod roll) has moved upward so that the second switch  14  is forced to rotate upward, thereby activating the second sensor  15 . The trailing edge of the sod piece  8  is still underneath the front rollup ladder  6 , with part of the sod piece  8  situated underneath the bottom end  12   a  of the first switch  12  (see  FIG. 13 ). As long as there is a piece of sod  8  underneath the bottom end  12   a  of the first switch  12 , the first sensor  13  will be deactivated.  FIG. 13  is a side section view of what is shown in  FIG. 12B ; the section is taken as indicated in  FIG. 4A .  FIG. 14  is a wider perspective view of what is shown in  FIG. 12A . 
         [0084]    The present invention comprises a controller (not shown) with embedded software that controls the flap control device. When the second sensor  15  is activated, this software causes the rollup conveyor  4  to start. Specifically, the controller software causes the rollup conveyor  4  to start when the second sensor  15  is activated, the encoder  16  to begin counting when the first sensor  13  is activated, and the rollup conveyor  4  to stop when the encoder  16  counts a certain number of intervals tan interval being a measure of distance traveled rotationally by the rollup conveyor  4 ). 
         [0085]      FIG. 15  is a side section view of the flap control device of the present invention shown with the trailing edge of the sod piece no longer situated underneath the tail of the first switch and the first sensor in an activated position. At this juncture, the trailing edge of the sod piece  8  has moved out from underneath the bottom end  12   a  of the first switch  12 , thereby causing the top end  12   b  of the first switch to move downward so that it is aligned with (in proximity to) the first sensor  13 . In this position, the first sensor  13  is activated. 
         [0086]    Activation of the first sensor  13  causes the encoder  16  to begin counting the rotational distance traveled by the rollup conveyor  4 . This particular interval is preferably adjustable by the operator to ensure that the sod piece  8  continues to roll and that it is not ejected onto the platform  18  until the trailing edge (or flap) of the sod roll is in the preferred position. In the position shown in  FIG. 16 , the sod roll has moved past the second switch  14 , and the sod roll is situated between the inclined conveyor  3  and the rollup conveyor  4 . The sod piece  8  continues to roll as long as it is situated between the inclined conveyor  3  and the rollup conveyor  4  and both conveyors are moving at the same speed. (As noted above, whenever the rollup conveyor  4  is on, it is preferably moving at the same speed as the inclined conveyor  3 .) 
         [0087]      FIG. 16  is a perspective view of the flap control device of the present invention shown with the sod roll in a fully rolled position hut with the flap not yet located in the preferred position.  FIG. 17  is a side section view of what is shown in  FIG. 16 . At this stage, the sod piece  8  is continuing to roll and will continue to do so until the encoder  16  reaches the end of its counting limit (that is, its measurement of the distance traveled by the rollup conveyor  4 ). At that point, the controller software causes the rollup conveyor  4  to stop. When the rollup conveyor  4  stops rotating, the sod roll  8  is ejected by the inclined conveyor  3  onto the platform  18 . 
         [0088]      FIG. 18  is a side view of the flap control device of the present invention showing two sod rolls on the platform. Note that the present invention ensures that each sod roll will be placed onto the platform  18  with the end of the roll (or flap) in the same position each time, even if the sod piece  8  does not start rolling as soon as the leading edge of the sod piece  8  hits the start gate  9 . If the sod piece  8  does not begin to roll until the leading edge of the sod piece  8  has passed the start gate  9 , then the sod roll will be smaller around by the time it hits the second switch  14  than it would have been had the sod piece  8  begun, to roll at the start gate  9 . In this situation, however, the sod roll will continue to turn longer (in between the inclined conveyor  3  and the rollup conveyor  4 ) because if will take longer for the trailing edge of the sod piece  8  to clear the bottom end  13   a  of the first switch  12 , thereby triggering the encoder  16  to count and the rollup conveyor  4  to stop after a certain interval. In other words, the present invention ensures that every sod roll is the same size before the encoder  16  begins to count because the trailing edge of the sod piece  8  must clear the bottom end  12   a  of the first switch  12  before the rollup conveyor  4  stops and the sod roll is ejected onto the platform  18 . 
         [0089]      FIG. 19  is a bottom perspective view of the second switch. As explained above, the second switch  14  is attached to two end collars  27  mat rotate (or pivot) about a bolt  24 . The bolt  24  extends through a collar  28  that is fixed to a plate  26 . The plate  26  in turn is attached (welded) to the rear rollup frame  7 . Note that the present invention is not limited to any particular configuration of the second switch  14 , as long as it is positioned between the first switch  12  and the rollup conveyor  4 , and as long as it is configured to interact with the second sensor  15 . For example, the second switch may be attached to either the rear rollup frame  7 , as shown in the drawings, or it may be attached to the front rollup ladder  6 . 
         [0090]    The invention described above, that is, with a second switch that starts the rollup conveyor upon being triggered by the sod roll, is an improvement over prior art (for example, the invention described in U.S. Pat. No. 7,021,584 ) because it provides a greater degree of accuracy in terms of starting the rollup conveyor. 
         [0091]    In the embodiment discussed above, the end of the roll (or flap) on each piece of sod that is deposited onto the platform  18  is in the same position; however, in an alternate embodiment, the software that controls the flap control device is programmed so that the first sod roll (also called the “end” roll) in a group of five sod rolls is rotated slightly longer than the other four sod rolls so that the flap is situated in a 10:00 position when the end roll is deposited onto the platform  18  (see  FIG. 20 ). In other words, for every fifth sod roll  8 , the controller software causes the rollup conveyor  4  to start when the second sensor  15  is activated (as described above), the encoder  16  to begin counting when the first sensor  13  is activated (as described above), and the rollup conveyor  4  to stop when the encoder  16  counts a certain number of intervals (the number of intervals being larger for the end sod roll than for the other four sod rolls in the same group). The duration of rotation of the end roll is preferably adjustable by the operator via a control screen in the cab of the harvester. 
         [0092]    In  FIG. 20 , six sod rolls are shown on the platform  18 ; five of these sod rolls will be picked up by the sod carrier (not shown) and deposited onto a pallet (not shown). Thus, the sixth sod roll (that is, the one closest to the inclined conveyor  3 ) will be the end roll in the next group of sod rolls. As used herein, the term “end roll” or means the roll of sod that is the first in a group of sod rolls that are sequentially deposited onto the platform  18  and picked up simultaneously by the sod carrier. When the group of sod rolls is deposited onto the pallet, the array of sod rolls appears neater and more attractive if the flaps on the end rolls (which face the outside of the pallet) are all in the 10:00 position. Note that the flaps on the next three sod rolls in the group do not need to be at a 10:00 position because they are interior sod rolls (that is, they do not lace tire outside of the pallet when the sod rolls are arranged on the pallet), and the flaps on these rolls are held in place by virtue of the feet that the flap abuts up against an adjacent sod roll. Although the fifth or last sod roll in the group is an exterior sod roll (that is, it does have a side that is exposed to the outside of the pallet), the flap on this sod roll faces inward rather than outward on the pallet and is held in place by abutting up against the adjacent sod roll; therefore, there is no need to over-rotate this particular sod roll either. 
         [0093]    Note that in the embodiment shown in  FIG. 20 , five sod rolls  8  constitute a group that is then lifted off of the platform  18  by the sod carrier and deposited onto a pallet. The present invention is not limited to any particular number of sod rolls being picked up at once; rather, the invention constitutes rotating the first or “end” roll in a group of sod rolls (all of which are picked up at the same time by the sod carrier) more than the other sod rolls in the group so that the flap on the end roll is positioned differently than the flap on the other sod rolls in the same group. In a preferred embodiment, the flaps on the five non-end sod rolls are in the 7:00 position, and the flap on the end roll is in a 10:00 position. 
         [0094]    In the embodiment shown in  FIGS. 20 and 21 , a rubber bumper  29  has been secured to the rear of the rear rollup frame  7  and extends beneath the rollup conveyor  4 . Preferably, the rubber bumper  29  extends the entire width of the rollup conveyor  4 . The purpose of this rubber bumper  29  is to prevent the flap on the end roll from opening up clockwise (that is, from flapping over from the 10:00 position shown in  FIG. 20  to a 1:00 or greater position) and getting caught up in the rollup conveyor  4 . The rubber bumper  29  is situated so that if the flap on the end roll were to open up (clockwise from the vantage point of  FIG. 20 ), the rubber bumper  29  would knock the flap back into place (that is, back into its 10:00 position). Although the bumper is rubber in a preferred embodiment, it could be made of any suitable material. 
         [0095]    Although the preferred embodiment of the present invention has been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fell within the true spirit and scope of the invention.