Abstract:
A mobile harvesting apparatus and method utilizes a stream of liquid, propelled under high pressure through at least one nozzle, to harvest produce. Preferably, a plurality of nozzles is provided. Additionally, it is preferred that, for each nozzle provided, there is an associated diverter plate. With this configuration, a stream of liquid exiting a nozzle will, after harvesting an item of produce, strike its associated diverter plate.

Description:
RELATED APPLICATION 
   This non-provisional application claims priority from provisional application No. 60/495,026, filed on Aug. 14, 2003. 

   FIELD OF THE INVENTION 
   The present invention relates generally to harvesting apparatuses and methods and, more particularly, to a harvesting apparatus and method utilizing a stream of water under pressure to harvest produce. 
   BACKGROUND OF THE INVENTION 
   The harvesting of leafy produce, such as lettuce, typically involves the use of a sharpened cutting implement of some type to cut the produce head from the remainder of the produce body. In the past, the cutting implement was typically a sharp knife. More recently, automated harvesting devices of various types have been employed, utilizing a band-saw type of cutting implement. U.S. patent application Ser. No. 10/207,779, filed Jul. 14, 2003, in the name of the applicants herein, relates to one type of harvesting apparatus and method utilizing a band-saw type of cutting implement. 
   There are certain limitations associated with prior art apparatuses and methods. The utilization of a sharpened cutting implement can be hazardous to workers operating in the vicinity thereof, and harvesting accidents do occur. Additionally, in the event the blade rusts or is otherwise not kept sufficiently clean, there is a risk of contamination of the harvested produce, and indeed the spreading of contamination from one plant to another. Still further, the use of a blade as a harvesting tool tends to “milk” the harvested produce, reducing shelf-life. 
   A need therefore exists for a harvesting apparatus and method that, among other things, eliminates the need for a sharpened cutting implement, including the risks of accident and contamination associated therewith, and that reduces “milking.” The present invention addresses this need and provides other, related, advantages. 
   SUMMARY OF THE INVENTION 
   In accordance with one embodiment of the present invention, a harvesting apparatus is disclosed. The harvesting apparatus comprises, in combination: at least one nozzle positioned on the harvesting apparatus at a height that is appropriate for the harvesting of produce; a source of liquid; and means for propelling the liquid through the nozzle under high pressure in a direction of an item of produce so that the liquid may harvest the item of produce. 
   In accordance with another embodiment of the present invention, a harvesting apparatus is disclosed. The harvesting apparatus comprises, in combination: a plurality of nozzles positioned on the harvesting apparatus at a height that is appropriate for the harvesting of produce; a source of liquid; means for propelling the liquid through the plurality of nozzles under high pressure in a direction of an item of produce so that the liquid may harvest the item of produce; and a plurality of diverter plates, each of which is associated with at least one of the plurality of nozzles and positioned on the mobile harvesting apparatus so that the liquid, after exiting its associated the nozzle and cutting the item of produce, will strike the diverter plate; wherein each the diverter plate is separated from its associated the nozzle by a seed line of produce; and wherein each the diverter plate is comprised of stainless steel. 
   In accordance with another embodiment of the present invention a method for harvesting produce is disclosed. The method comprises the steps of: harvesting an item of produce utilizing liquid propelled under pressure through at least one nozzle; wherein the at least one nozzle is located on a mobile harvesting apparatus; and wherein the mobile harvesting apparatus travels on wheels. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of an embodiment of a lettuce harvesting apparatus, consistent with an embodiment of the present invention. 
       FIG. 2  is a front view of the lettuce harvesting apparatus of  FIG. 1 . 
       FIG. 3  is a top view of the lettuce harvesting apparatus of  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring first to  FIG. 1 , an embodiment of the lettuce harvesting apparatus  10  (“apparatus  10 ”) of the present invention is shown. The apparatus  10  is intended to be used for the harvesting of produce. It is preferred to use the apparatus  10  to harvest celery and lettuce (including romaine lettuce), though other types of produce may also be harvested using an embodiment of the apparatus  10  of the present invention. 
   In one embodiment, the major components of the apparatus  10  may include a water-cutting apparatus  12  (which will be described in more detail below), a feed conveyor  14 , a lift conveyor  16 , an inspection conveyor  18 , a washing station  20 , a transfer conveyor  22 , and at least one elevator conveyor  24 . The apparatus  10  may be powered by an engine  26 , ride on wheels  28 , and may be driven by a person  29  sitting in driving compartment  30 . (It should be noted that instead of being self-propelled, it would be possible to have the apparatus  10  be towable by another vehicle. In addition, instead of traveling on wheels, the apparatus  10  could be configured to travel on a track assembly.) 
   The water-cutting apparatus  12  may be positioned at the front of the apparatus  10  as shown in  FIGS. 1-3 . The water-cutting apparatus  12  may consist of at least one and preferably a plurality of water nozzles  32  positioned at the base of the feed conveyor  14 . The nozzles project water under high pressure, in a direction that is substantially parallel to the level of the ground, and across the front (i.e., perpendicular to the seed line being harvested) of the feed conveyor  14 . The height of the nozzles  32  should be adjustable, for example in the manner described below, so that the cutting height may be adjusted as desired. 
   It is preferred that there be six nozzles  32 , each of which is coupled to a corresponding diverter plate  34 . The diverter plates  34  should be positioned at the front of the feed conveyor  14 . As best shown in  FIG. 2 , the spacing of the diverter plates  34  should be sufficient to permit a single seed line of the produce that is to be harvested to pass between neighboring diverter plates  34 , so that produce in a single seed line is being harvested as it passes between neighboring diverter plates  34  and is exposed to the spray from a nozzle  32 . The spray of the nozzles  32  is preferably aimed so that it contacts the neighboring diverter plate  34 , or, particularly for the nozzle  32  on the end diverter plate  34 , otherwise contacts a shielding device of some kind after passing through the produce to be harvested, so as to avoid injuring a worker passing nearby. 
   The diverter plates  34  are preferably comprised of stainless steel, for food safety reasons. They preferably have a height of about 24 inches, a depth (from leading edge to trailing edge) of about 10 inches, and a width of about 0.5 inches. It should be noted that deviation, including of a fairly substantial nature, would be possible from these dimensions without departing from the spirit or scope of the present invention. As shown in  FIG. 1 , it is preferred that the leading edge of the diverter plates  34  have a rounded anterior, inferior edge. 
   The diverter plates  34  are preferably coupled proximate a superior portion thereof to horizontal header bar  36 . Such coupling preferably permits height adjustment of the diverter plates  34 , and thus of the nozzle  32  coupled thereto. Side to side adjustment of the diverter plates  34  should also be permitted, to take into account the seed line size of the particular produce that is to be harvested. It is also preferred that the coupling of the diverter plates  34  permit the removal of at least one diverter plate  34  as necessary for a particular harvesting application. For example, where there are fewer seed lines, it may be desired to remove one or more diverter plates  34  and associated nozzle(s)  32  so that there will only be as many nozzles  32  as there are seed lines to harvest, so as to avoid the unnecessary wasting of water. Preferably, removal is facilitated by providing for rotational coupling of the diverter plates  34  to the horizontal header bar  36 , so that an unneeded diverter plate  34  can be rotated upward and away from the base of the feed conveyor  14 . 
   Water should be propelled from each nozzle  32  at a pressure and spray size sufficient to harvest the particular produce with which the apparatus  10  is being utilized. For most applications, including particularly celery, a pressure of about 25,000 pounds per square inch will be sufficient, projected from a nozzle having an orifice size of about 0.01 inches. At these specifications, water would be utilized at the rate of approximately 0.25 gallons, per minute, per nozzle. It is further preferred that the water utilized be filtered down to about one micron, so as to reduce orifice wear. 
   The water that is to be propelled from each nozzle is preferably fed through tubes  38  (see  FIG. 1 ) that couple between a water tank  40  and the nozzle  32 . A possible location for the water tank  40  is shown by way of example in  FIG. 1 , though other locations may be desired. The water tank  40  may have any desired capacity, taking into account the nature of the particular harvesting task, with a volume of about 500 gallons being considered sufficient and desirable for most applications. 
   It should be noted that it is preferred to provide a back-up nozzle  32   a  (see  FIG. 1 ) proximate each nozzle  32 . The purpose of the back-up nozzles  32   a  is to permit their utilization in the event of clogging, or other failure on the part of its corresponding main nozzle  32 . Preferably, a valve or other switching mechanism should be interposed between the nozzle  32  and its associated back-up, so as to permit switching therebetween. 
   The feed conveyor  14  may, in one embodiment, be coupled to a lift conveyor  16 . Such coupling may be as described in Ser. No. 10/207,779, filed Jul. 14, 2003, incorporated herein by reference. The entire feed conveyor  14  preferably maintains a generally upward angle, as indicated in  FIG. 1 . The belt  42  of the feed conveyor  14  travels in an upward direction, so as to move harvested produce from the front of the feed conveyor  14  upward toward the lift conveyor  16 , where provided. 
   Turning now to the lift conveyor  16 , as shown in  FIGS. 1 and 2 , it is preferably oriented in an upward direction, when viewed moving backward along the apparatus  10  from the feed conveyor  14 . The feed conveyor  14  is preferably oriented at about a 45 degree angle. The belt  44  of the feed conveyor  14  preferably has a plurality of outwardly projecting steps  46 . The purpose of the steps  46  is to prevent the produce from falling backward as it is moved upward along the lift conveyor  16 . 
   Means for leveling the apparatus  10  are also, preferably, provided. By way of example, these may be as set forth in Ser. No. 10/207,779, filed Jul. 14, 2003, incorporated herein by reference. 
   When the produce reaches the topmost point of the lift conveyor  16 , it will pass to the inspection conveyor  18 . As the produce moves along the inspection conveyor  18 , it will pass through a washing station  20 . 
   Referring now to  FIG. 1 , in one embodiment, a portion of the inspection conveyor  18  may be left exposed from the top thereof, so as to permit one or preferably two persons  29  to be positioned on either side thereof. (The number of persons  29 , if any, desired for the inspection conveyor  18  will depend on harvesting conditions. For particular applications, more than two persons  29  may be desired on one or both sides of the inspection conveyor  18 , including for example eight persons  29  per side for some applications.) From that position, the persons  29  may inspect the produce as it passes along the inspection conveyor  18 , for purposes of quality control. Alternatively, or in combination with the inspection step, one or more persons  29  could remove harvested produce (or a portion of harvested produce—e.g., the heart or the leaves) from the inspection conveyor  18  for packaging. (It should be noted that it would also be possible to position the exposed portion after the washing station  20 .) 
   Referring now to  FIGS. 2-3 , it is preferred that from the end of the inspection conveyor  18 , the produce may be alternatively routed via a transfer conveyor  22  to first or second elevators. Such a configuration will permit the routing of harvested produce to one of two destinations, including for example a tote bin or trailer. 
   Water-cutting confers a number of benefits as compared to prior art cutting methods. For example, water cutting is cleaner. Where a blade is used, the blade can rust, or can spread disease or other contamination from one plant to another. In addition, water cutting tends to cauterize the harvested produce to a greater extent than blade cutting, reducing “milking” and increasing shelf-life. 
   While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention. 
   For example, it may be possible to operate the feed conveyor  14  with the water cutting apparatus  12  as a stand-alone unit, so as to achieve the advantage of automated cutting of the produce—and then performing the washing and loading steps separately. Moreover, the feed conveyor  14  and lift conveyor  16  could be combined into a single conveyor. Still further, it would be possible to eliminate the transfer conveyor  22 , and instead to configure the elevator conveyor  24  in combination with the steps  46  so that produce could pass directly from the inspection conveyor  18  to the elevator conveyor  24  without falling backward. Yet further, it would be possible to eliminate both the transfer conveyor  22  and elevator conveyor  24 , with dumping of the produce taking place at the terminus of the inspection conveyor  18 . Still further, the number, size, spray direction, and positioning of the nozzles  32  may be varied as desired, so long as they are able to cut produce during the harvesting process.