Abstract:
A transplanting apparatus which can plant virtually 100% of the seedlings from a nursery tray, while avoid skips when planting which may happen when seeds in a tray row fail to grow into seedlings. This is accomplished by picking up an entire row of seedlings from a tray, transferring the seedlings to a mechanism which eliminates gaps between seedlings, and then discharging the seedlings one at a time to the ground with a desired spacing between the seedlings while having full physical control of the seedlings. 
     A root ball compressor is provided to provide better control of the seedlings as the compressed root balls are less likely to tip over, and the compressed root balls are easier to be grabbed by the pinch disks.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation-in-part of U.S. patent application Ser. No. 12/221,081 filed Jul. 31, 2008, and entitled TRANSPLANTER, and published as US-2009-0031935-A1. This application also claims priority from U.S. provisional patent application 61/206,804 filed Feb. 4, 2009 and U.S. provisional patent application 61/274,988 filed Aug. 24, 2009. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates generally to transplanting apparatus, and more particularly to one which can plant virtually 100% of the seedlings from a nursery tray, while avoid skips when planting which may happen when seeds in a tray row fail to grow into seedlings. This is accomplished by picking up an entire row of seedlings from a tray, transferring the seedlings to a mechanism which eliminates gaps between seedlings, and then discharging the seedlings one at a time to the ground with a desired spacing between the seedlings while having 100% control of the seedlings. 
       BACKGROUND OF THE INVENTION 
       [0003]    Transplanting apparatus is well known in the art. Typical transplanters, which transplant from a plant tray, are shown in U.S. Pat. Nos. 4,644,880; 5,431,116; 5,573,558; 5,676,072; 6,073,564; and 6,634,306. Frequently there are skips between seedlings which may occur when seeds in a tray row fail to grow into seedlings. Transplanters which try to eliminate skips include U.S. Pat. No. 6,327,986 which discloses three separate sets of sensors to look for plant skips and advance a root ball chamber belt assembly one cell to make up for skips and eject the deficient root ball at the same time. U.S. Pat. No. 6,080,951 discloses another approach to overcome the seedling tray skip problem. These approaches rely heavily on the accuracy of detectors to sense the presence of plant foliage. Considering the chaotic nature of the foliage and the necessary speed to be efficient, there is substantial room for error in these systems. Prior U.S. published application No. US-2009-0031935-A1 uses conveyor belts which push together the root balls of the rows of plants extracted from a plant tray. 
         [0004]    Unfortunately, the root balls in a tray, when received at the transplanter, are not always firm and fully packed, making the subsequent handling somewhat difficult. Thus the root ball may tip over when placed on a conveyor belt. In addition, it may be difficult for a pinch disk to grab the root ball. 
         [0005]    In U.S. published application No. US-2009-0031935-A1, the subject matter of which is incorporated herein by reference thereto, after gaps between seedlings have been eliminated, individual seedlings pass through a drop tube to a mechanism for discharging the seedlings one at a time to the ground with a desired spacing between the seedlings. 
         [0006]    It is a feature of the foregoing patent application that the transplanter has a forward pair of transfer disks; a rear pair of planter disks; and an air knife mounted adjacent the forward pair of transfer disks for extending the stem and foliage of a seedling while in the forward pair of transfer disks for proper engagement by the rear pair of planting disks. It has been found that approximately 95% of seedlings will pass through a drop-tube type planter system without issues. The last 5% consists of plants with poor root systems, crooked stems, dwarfed size and soft stems. These types of plants tend to drag on the side of the drop tube and travel slowly because the soil has dislodged from the root ball or tipped over because of the soft stems. This results in skips and drop tube plugging issues. 
       OBJECTS AND SUMMARY OF THE INVENTION 
       [0007]    It is an object of the present invention to overcome the problems which occur when trying to transplant poor quality seedlings, which may have poor quality root balls, crooked stems, dwarfed size, tangled foliage, soft stems, etc. 
         [0008]    More particularly it is an object of this invention to provide a transplanting method for transplanting seedlings grown in trays having a plurality of side-by side rows of seedling cells, which method plants the seedlings uniformly apart even though not all cells have seedlings, the method including the steps of picking up an entire row of seedlings from a tray by engaging the stems of the seedlings, which row in the tray may have gaps between seedlings, transferring the seedlings to a mechanism which eliminates gaps between seedlings, and, maintaining full control of each seedling as it is moved from the mechanism which eliminates gaps to the ground one at time with a desired spacing between the seedlings to a mechanism which plants the seedlings; whereby the seedlings are planted uniformly spaced apart in the ground. 
         [0009]    It is a further object of the present invention to provide a transplanting apparatus for transplanting seedlings grown in trays having a plurality of side-by side rows of seedling cells, which transplanting apparatus plants the seedlings uniformly apart even though not all cells have seedlings, the transplanting apparatus having means for picking up an entire row of seedlings from a tray by engaging the stems of the seedlings, having means for eliminating gaps between seedlings, and means for discharging and planting the seedlings while maintaining full control of the seedling as they are moved from the means for eliminating gaps until they are planted. 
         [0010]    It is an additional object of the present invention to provide a transplanting apparatus of the type set forth above with means for compressing the root balls along their length so they can be handled better, the compressing means being located between the means for eliminating gaps and the transferring means. 
         [0011]    The above and other objects and advantages of this invention will become more apparent from a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the invention is illustrated. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0012]    In the following views right hand and left hand reference is determined by standing behind the transplanter and facing its direction of travel. In addition, terms such as raised and downwardly are with reference to the parts as shown in the various views. 
           [0013]      FIG. 1  is a left side elevational view of a one row transplanter of this invention mounted behind a tractor, this view showing the mechanism for picking up an entire row of seedlings from a tray, transferring the seedlings to a mechanism which eliminates gaps between seedlings, and a discharge and planting mechanism for discharging the seedlings one at a time to the ground with a desired spacing between the seedlings, some parts not being illustrated. 
           [0014]      FIG. 2  is a side view showing a number of seedlings on gap up belts with the cut-off gate extended to its raised position, and the root ball pinchers retracted, permitting the row plants to travel up to the cut-off gate and to gap up any missing plants, a root ball compressor and cut-off knives being shown in their raised retracted position. 
           [0015]      FIG. 3  is a partial section taken generally along the line  3 - 3  in  FIG. 2 . 
           [0016]      FIG. 4  is a side view, similar to  FIG. 2 , but showing the cut-off gate retracted, the trash knives extended downwardly, the overhead root ball compressor extended downwardly to crush the root balls to approximately ¾ of their original length, the first set of inverter disks gripping a single root ball, and the root ball pinchers extended to secure all root balls on the gap-up belts. 
           [0017]      FIG. 5  is a section taken generally along the line  5 - 5  in  FIG. 4 . 
           [0018]      FIG. 6  is a view similar to  FIG. 1 , but on a larger scale, some nonessential parts not being shown. 
           [0019]      FIGS. 7 and 8  show the transplanter of this invention when planting 5 inch seedlings,  FIG. 7  showing the planter subframe when planting in a seedbed which is raised above the tractor wheels, and  FIG. 8  showing the planter subframe when planting in a flat field. 
           [0020]      FIGS. 9 and 10  are views similar to  FIGS. 7 and 8 , but showing the transplanter of this invention when planting 9 inch seedlings. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    The transplanter of this invention is indicated generally at “T” in  FIG. 1 . It may be semi-integrally mounted on the three point hitch  20 ,  22 ,  24  of a tractor  10 , only a portion of which is shown in  FIG. 1 . A box-like subframe indicated generally at  30  is in turn carried by the three point hitch. Mounted on the back of the subframe  30  is a tool bar  32  which in turn carries a pivoted sub-frame, not shown, for supporting wheels, also not shown. Each of the wheels may be moved up and down. As this design is conventional, it is not illustrated. 
         [0022]    Mounted on the sub-frame  30  are high volume and high pressure air compressors, a 24 volt alternator, and a 24 volt battery source, the compressors and alternator being powered by the PTO shaft  42  of the tractor  10 . The transplanter includes an operator support or platform  50 . Mounted on the operator support  50  is a horizontal transplanter subframe  52 . This in turn carries vertical subframe assemblies indicated generally at  54  and  56 . An arched subframe  58  extends from a location above the top of the vertical subframe  54  forwardly and downwardly to a location adjacent subframe  56 . The arched subframe  58  carries many air lines and electrical controls, not shown. In addition, control modules  62  may be mounted on the subframe  58 . A high pressure air reservoir  70  and a low pressure air manifold  72  are carried below the platform  50 . 
         [0023]    The transplanter consists of several major subassemblies. A first major subassembly is the tray indexing mechanism (not shown). The subassembly for picking up an entire row of seedlings from a tray is indicated generally at  300 . These various components of the transplanter of this invention will not be discussed in detail as they are adequately discussed in US published application 2009-0031935-A1. The subassembly which eliminates gaps between seedlings is indicated generally at  500  and includes continuously running gap-up belts  506 ,  508 , and a cut-off gate  510 , as shown in  FIGS. 2-5 . These various components will be discussed in detail below. In addition to the above, there is a planter assembly, which plants individual seedlings in the ground, the planter assembly including a planter frame subassembly indicated generally at  800 , which frame subassembly supports furrow opening and closing mechanisms. 
       Gap Eliminating Subassembly 
       [0024]    The subassembly which eliminates gaps between seedlings and which compresses the root balls is best illustrated in  FIGS. 2-5 . The gap eliminating subassembly includes a plant transfer carriage or seedling loader group, which group carries root ball which will engage the root balls RB of the seedlings and move them towards and over a pair of gap-up belts  506 ,  508  which run continuously during the operation of the apparatus of this invention. As the root ball loaders of this invention are more fully described in US published application 2009-0031935-A1, they will not be described in detail here. When the root balls of the seedlings are fully positioned over the gap-up belts, they will be released by the root ball loaders, and the tops of the root balls, which are in an upside-down position, will rest on the gap-up belts for movement towards a cut-off gate  510 . The cut-off gate will be operated in a suitable manner to release one seedling at a time, which seedling will be picked up by a discharge mechanism, or inverter disk assembly  700 , which includes outer and inner disks  703 ,  705  best shown in  FIG. 1 . 
         [0025]    The root ball loaders are moved between a forward position and a rear position by an air cylinder assembly  544 , which includes cylinder  545 . The anchor end of cylinder  545  is supported by a transverse structure  520  which is in turn supported by right and left side plates  516 ,  518 . An air manifold block  592  is supported on the cylinder  545  by upper and lower clamps  522 ,  523  as shown in  FIG. 5 . 
         [0026]    As set forth above, the gap-up belts  506 ,  508  are driven continuously during the operation of the machine and will cause the root balls RB placed on the belts to move towards a cut-off gate  510 , closing up the root balls and eliminating any gaps between the root balls which may be caused by seeds failing to germinate, or the like. More particularly, the cut-off gate  510  has the function of stopping the lead root ball so that next trailing root ball will press against the leading root ball, thus eliminating any gaps. In addition, the cut-off gate will be operated to release individual root balls at precise intervals to insure that proper planting spacing may be achieved. In the illustrated embodiment, the single cut-off gate  510  is operated by a pair of double acting air cylinders  680 , only one of which is shown, which cylinders are supported for adjustable longitudinal fore and aft movement by a carriage assembly  682  supported for adjustable movement on a pair of longitudinally extending rods  684  which are in turn supported by opposed plates  686 . The plates are in turn supported on the right and left upper side plates  516 ,  518  in any suitable manner. A screw mechanism including a screw  688  may be used to adjust the position of the gate to accommodate root balls of differing diameters as differing nurseries use plant trays having differing sized cells. 
         [0027]    According to this invention means are provided to compress the root balls while on the gap-up belts  506 ,  508 . To this end an L-shaped bracket  692  is mounted on a further transverse structure  521  as shown in  FIG. 5 , upon which are mounted double acting air cylinder assemblies  694 . The rods  695  of the cylinder assemblies are secured to a transverse plate  696  which carries at its lower end a longitudinally extending member  697  which may contact the root balls RB. Cut-off knives  734  are carried by L-shaped brackets  736  mounted on the transverse plate  696 . As the root balls RB move towards the cut-off gate, the knives  734  will strip away excess trash which may be associated with the root balls. In addition, the knives will move up and down with the rood ball compressor  697 , and this movement will facilitate the removal of the trash associated with the root balls 
         [0028]    The operation of the cut-off gate cylinder assembly  680  is responsive to a PLC (or the equivalent) trigger input received from a wheel encoder processor, which is in turn responsive to a signal generated from a wheel encoder carried by a sensing wheel (not illustrated) which generates a distance signal as a function of the distance traveled by the transplanter. In addition, root ball pinchers, indicated generally at  702  in  FIGS. 3 and 5 , will act in concert with the gate  510 , to control the discharge of a root ball at selected time intervals. The right and left root ball pinchers  702  are mounted on the upper edge of the right and left upper side plates  516  and  518 , respectively. To this end, each of the root ball pinchers includes a L-shaped bracket  706  secured to a bar  708  secured to an upper end of the side plate  516  or  518 . The cylinder  710  of a double acting air cylinder assembly is secured to the L-shaped bracket  706 , the rod  712  of the cylinder passing through the bracket  706 , the root ball pinchers  702  being secured to the end of the rod  712 . Each root ball pincher includes a flared pressure plate  716  mounted on a block  718 , which is in turn secured to the rod  712 . Simultaneous actuation of the cylinder assemblies  710 ,  712  will cause opposed root ball pinchers in the form of the pressure plates  716  to either move towards each other to pinch and hold the root balls from further movement, or to release the root balls so that they can be advanced,  FIG. 3  showing the root ball pinchers in their retracted position, and  FIG. 5  showing the root ball pinchers in their root ball holding position. 
         [0029]    In operation, the cylinder assemblies  710  will be operated at substantially the same time to extend the pressure plates  716  into engagements with the sides of the root balls, and, at the same time, the cylinder assemblies  694  will be operated simultaneously to force the longitudinally extending member  697  into contact with the bottom of the inverted root balls RB which are between the pressure plates  716  to compress the root balls RB along their length. As can be seen from  FIGS. 2 and 4 , not all root balls are compressed, but the ones nearest the cut-off gate  510  are. At or near the full extension of the cylinder assemblies  694  and  710  the cylinder assembly  680  will be retracted to permit the leading seedling to be discharged to the disks  703 . It should be noted that the timing to the cylinders  694  and  710  is coordinated with the timing of the gate cylinder assembly  680 . After the leading root ball has been discharged, all of the cylinders  680 ,  694 , and  710  will be moved to their initial position. 
       Plant Delivery System 
       [0030]    In accordance with this invention a plant delivery system is provided which maintains 100% control of the seedlings after they leave the cut-off gate  680  of the gap eliminating mechanism. Thus there is provided an inverter disk assembly indicated generally at  700  and which is supported on shaft  615  ( FIG. 6 ), a middle plant transition disk assembly  901  carried by arms which extend downwardly from shaft  615 , and a row unit disk assembly  1301  carried by the planter subassembly  800 . The shaft  615  is carried by the transplanter subframe  52 , the shaft  615  and gap-up belts  506 ,  508  being driven by a DC motor in the same manner as shown and described in US-2009-0031935-A1. 
         [0031]    As best shown in  FIG. 6 , the inverter disk assembly  700  consists of a pair of flexible outer disks  703  and a pair of flexible inner disks  705 , which are of a lesser diameter. Means are provided to move the periphery of each of the pairs of disks towards and away from each other as they are rotated in a counter clockwise direction as viewed in  FIG. 6 . Thus, the periphery of the outer disks, when in the 12 o&#39;clock position, will be moved towards each other to grasp each discharged root ball. The root balls are caused to be rotated to the 7 or 8 o&#39;clock position with the outer disks  703 . At this location the periphery of the inner disks  705 , which are rotating at the same speed as the outer disks, will be moved towards each other to capture and/or pinch the plant foliage of each seedling. After a little more rotation, the periphery of the outer disks  703  will forced apart to release the root ball. To this end, the side plates  516 ,  518  and each of the arms  801  carries supports for rollers and shields which will cause the disks  703  and  705  to open and close at the appropriate times, the rollers preferably being carried by suitable leaf springs. It is a feature of this invention that the pair of outer disks  703  is formed of high density polyethylene plastic which have their outer periphery formed with many apertures as shown in  FIG. 6  for the purpose of providing a more flexible and aggressive surface. 
         [0032]    The middle plant transition disk assembly  901  includes a pair of high density polyethylene plastic disks  902  secured to rotatable shaft  903  for clockwise rotation therewith. The shaft  903  is carried by a pair of fixed length swing arms  801  which are journalled at their upper ends on the shaft  615  and at their lower ends to shaft  903 . The shaft  903 , including the disks mounted on it, has its speed synchronized to the inverter disk assembly  700 . To this end, it is caused to be driven by a chain or cogged belt  904  which passes over suitable drive, driven, idler, and tensioning sheaves, which are not numbered. As shown, the drive sprocket or sheave is supported on shaft  615 , the idler and tensioning sheaves are supported on side plate  518 , and the driven sheave is keyed to the shaft  903 . Rollers and shields will cause the disks  902  to open and close at the appropriate times. A foliage shield located at approximately the 11 o&#39;clock position as seen in  FIG. 6  will cause the disks  902  to be spread apart for the reception of the root balls carried by the disks  703 . Meanwhile, as set forth above, the disks  703  are being spread apart as they approach the 6 o&#39;clock position, releasing the root balls for transfer, and during the same time the inner pair of disks  705  will engage the stem and foliage of the seedling to insure that the seedling is under control during the transfer. As the rollers  902  approach the 1 or 2 o&#39;clock position the rollers  909  on leaf springs will force the disks  902  towards each other while a shield (not shown) causes the inner inverter disk  705  when it reaches the 5 o&#39;clock position to be spread apart, thereby releasing the foliage of the root ball being transferred to the middle plant transition disk assembly. 
         [0033]    A pair of telescoping lower drag link assemblies  910  is also secured at their upper ends to shaft  903  and its lower end to the shaft  1303 . This structure is necessary to deal with the up and down movement of the of the row unit, or planter frame subassembly,  800 , as adjustments may be necessary to deal with seedlings of differing heights. 
         [0034]    The row unit planter frame subassembly  800  is adapted to be secured to the tool bar  32  shown in  FIG. 1 . The subassembly, which is more fully disclosed in US-2009-0031935-A1, includes a mounting weldment  802  secured to the tool bar in any conventional manner. Upper and lower parallel links  804  and  806  are pivotally secured to the weldment, and the rear ends of the upper and lower links are pivotally secured to a further weldment  812 . Upper and lower rearwardly extending structures  818  and  820 , respectively, are secured to the weldment  812 . In addition a cylinder  807  is mounted between the weldment  802  and the weldment  812  for the purpose of applying either a raising or a lowering force to the weldment  812 . A soil conditioning unit, indicated generally at  821 , is pivotally secured to the lower end of weldment  812 . The height of the soil conditioning unit can be adjusted by a screw mechanism (no number). A furrow opener  830  is secured to the lower rearwardly extending structure  820  by a vertical bar  832 . The furrow opener is of a generally V shaped construction, the apex of the V being to the forward side, and the spaced apart sides of the V being flared to the upper side. As can be seen from a comparison of  FIGS. 7-10 , the planter subassembly can be moved to a raised position, as shown in  FIGS. 7 and 9 , or to a lowered position when planting in a flat field as shown in  FIGS. 8 and 10 . 
         [0035]    Each of the telescoping lower drag link assemblies  910  includes telescoping tubular portions  912  and  914  which are caused to move relative to each other by a suitable mechanism  916 , which causes telescopic movement. One of the tubular portions  914  has an end portion journalled about shaft  903 , and the other tubular portion has an end portion journalled about shaft  1303 , shaft  1303  being journalled to the planter subframe  800 . Each of the forward tubular portions carries a foliage shield and also carries a vectoring air knife  920  which blows the foliage and stem of the root ball away from the disks  902  to straighten the foliage to facilitate a hand-off to the disk assembly  1301  which include a pair of planting disks  1304 ,  1305 . The drive for the disks includes a motor  1308  mounted on side plates  1109 . The speed of the motor is proportional the speed of a ground wheel and is controlled in a manner more fully set forth in published U.S. patent application US-2009-0031935-A1. The disks  1304  and  1305  may be made of high density polypropylene, aore they may be made of fiber reinforced rubber. 
         [0036]    As can be seen from a comparison of  FIGS. 7-8  with  FIGS. 9-10  the distance between the disk assembly  901  and the disk assembly  1301  may be varied. Thus,  FIGS. 7 and 8  show the distance between the disk  901  and  1301  when planting seedlings with 5 inch tall plants, and  FIGS. 9 and 10  showing the disk positions when planting seedlings with 9 inch tall plants. As can be seen the disks  902  will be moved forwardly within the planter subassembly  800  when planting seedlings having longer stems. 
       SUMMARY 
       [0037]    Plants are extracted from the tray and travel through the indexer up to the cut-off gate by the same method used on the original design. The inverter disc has been equipped with a pair of smaller diameter discs inside the original disc. When plants are discharged at the cut-off gate, the inverter disc grabs the root balls as normal. The inverter discs rotate the root ball to approximately the 7 or 8 o&#39;clock position. At this location, the smaller diameter disc captures and pinches the plant foliage while the larger disc spreads apart allowing the root ball to hang free. Next, the middle transition discs capture the root ball and rotate the plant to the row unit planting disc. Vectoring air knives and shielding straighten the plant foliage to facilitate a hand-off to the row unit disc. To deal with the up and down movement of the row unit, the middle transition disc hangs on swing arms mounted from the inverter disc. Twin telescoping drag links connect the middle transition link to the row unit. An electric servo is coupled onto one of the telescoping drag links for changing stand off distance between the middle disc and the planting disc for different length plant stems. In operation, the middle transition disc swings forward as the row unit comes up and back as it drops, but always maintains the same plant hand off positions from disc to disc. 
         [0038]    While a preferred form of this invention has been described above and shown in the accompanying drawings, it should be understood that applicant does not intend to be limited to the particular details described above and illustrated in the accompanying drawings, but intends to be limited only to the scope of the invention as defined by the following claims. In this regard, the terms as used in the claims are intended to include not only the designs illustrated in the drawings of this application and the equivalent designs discussed in the text, but are also intended to cover other equivalents now known to those skilled in the art, or those equivalents which may become known to those skilled in the art in the future.