A. Field of the Invention
The field of the present invention relates generally to apparatuses for harvesting grapes, raisins and other crops. More particularly, the present invention relates to such apparatuses that are configured for collecting crops from the field that are disposed on continuous trays, such as those made out of paper and the like. Even more particularly, the present invention relates to such apparatuses that reduce labor by separating the crop from the continuous trays and depositing the crop in a bin or like receptacle.
B. Background
As is generally well known, the conventional methods of harvesting grapes, raisins and other vine crops is typically a very labor intensive process requiring a significant number of laborers to separate the crop from the vines and then harvest the crop from the field. Such methods generally require labor crews to walk through the vineyard and individually cut clusters of the fruit from the vine. As such, the economics of producing vine crops is subject to and substantially driven by such factors as labor availability, ever increasing labor and material costs, and, with regard to dried fruit, unpredictable weather. The conventional method of growing raisins is to grow grape vines in separate, generally parallel rows utilizing a trellis system that runs along the row, producing rows of vines that stand approximately four to six feet high. The predominate method of harvesting raisins in use today utilizes manual labor to cut the grapes from the vines, remove the grapes from the stems and then place the bunches of grapes on individual paper sheets, typically two feet by two feet in size and commonly referred to as trays, to dry in the sun. Periodically, the laborers turn the grapes on the trays to obtain more thorough drying. Once dried, the paper trays are folded and rolled, with the raisins disposed inside, and collected from the field. Once collected, the raisins are then separated from the trays, placed in raisin bins and delivered to packing houses for final processing before being sold.
While the above method has been successfully utilized for many years, the use of individual paper trays had a number of limitations with regard to the efficient harvesting of raisins. For instance, the laying out and later collecting of the individual paper trays is quite labor intensive. The removal of the grapes from the vines and their placement on the individual paper trays also requires a significant amount of labor. With increasing labor costs, this type of raisin production has become relatively very expensive and, therefore, less attractive to many raisin growers than more modern raisin production methods. The general unavailability of labor to perform the necessary operations to harvest the raisins in this manner, has only compound the problems facing the grower who is utilizing the conventional method of harvesting raisins.
As a result of increased labor costs and labor unavailability, many growers have opted to utilize one of the newer mechanized methods of raisin production. Two of the most common methods of raisin harvesting which take advantage of the benefits of increased mechanization are the continuous paper tray method of harvesting, to which the present invention pertains, and the dried-on-the-vine or DOV method of harvesting. Although the DOV method of harvesting raisins has certain advantages with regard to the process of drying grapes into raisins and mechanization of the harvesting of the dried raisins, it has certain disadvantages that has prevented many growers from being able to switch to DOV harvesting. Chief among the disadvantages is that most of the DOV methods of harvesting raisins require the vines to be grown in a specialized manner which facilitates later cutting a portion of the vine to cause the grapes to dry into raisins while still attached to the vine. The cost of installing a trellis system that advantageously supports the vines for the chosen DOV method and the cost of the equipment to efficiently and effectively harvest the DOV raisins hanging on the vines creates substantial barriers for many growers to the utilization of one the various DOV methods.
The continuous paper tray method of harvesting raising utilizes a paper tray which is laid out from a roll of paper instead of the individual two foot by two foot trays. The continuous paper tray typically extends the entire length of the area between two adjacent rows of vines. As with the individual paper trays, the continuous paper tray is typically laid out shortly before it is time to cut the grapes from the vines and place them on the continuous paper tray for drying in the sun. Once the raisins are sufficiently dry, the continuous paper tray and raisins are picked up from the field and taken to a packing facility for cleaning and/or other processing. Although the laying out of the continuous paper tray, removal of the grapes from the vines and placement of the grapes on the continuous paper tray, and the subsequent collecting of the raisins and paper tray can be done by utilizing hand labor, this would eliminate many of the benefits of this method of growing raisins. As a result, various procedures and mechanisms have been developed to improve the efficiency of raisin production and to reduce the costs associated with harvesting raisins by the continuous paper tray method. One mechanical method of harvesting/drying raisins with a continuous paper tray requires special soil preparation, namely that the row must be free of weeds and terraced smooth. The canes are hand cut about ten days prior to harvest so that the grape can be removed from the cluster with the stem attached. The grapes are then removed from the vines with a mechanical vibration system and simultaneously placed on a continuous tray. This procedure requires a four man crew. After the raisins are dried, they are mechanically removed from the tray and deposited into a bin trailer in the adjacent row using a mechanical conveyor system. This process requires two machines and two operators.
Some of the mechanisms for harvesting with continuous paper trays are addressed to machines capable of removing the green grapes from the vines and then placing them on the paper trays for drying. For instance, U.S. Pat. No. 2,869,284 to Abernathy, et al. describes an apparatus configured to unroll a strip of paper between adjacent rows of vines and cut the paper at the end of the row while it simultaneously deposits fruit on the paper. It is believed that this is one of the earliest patents to describe the placement of grapes on paper for the continuous paper tray method of harvesting raisins. U.S. Pat. No. 3,587,931 to Studer, et al. also describes a machine for depositing a continuous strip of paper tray on the ground and grapes on top of the paper tray. While both of these patents describe apparatuses for laying the continuous paper tray between the rows of vines and depositing grapes thereon for drying, neither patent addresses the need to later collect the raisins from the field.
As stated above, once the continuous paper tray is laid out on the ground and the grapes are placed on top thereof, there exists a need to collect the raisins from the field and separate them from the continuous paper tray. U.S. Pat. No. 3,762,577 to Olmo, et al. describes a raisin pick-up machine having a carriage that advances along the strip of paper in a manner that applies tension to the paper as the carriage advances. From the tensioned strip, the raisins are brushed into a receiver for conveyance to a bin carried by the machine. An elevating conveyor and presser wheel at the front of the machine start the paper into the tensioner. U.S. Pat. No. 3,955,343 to Tico describes a fruit harvesting machine for picking up, rolling up and storing a continuous paper strip having fruit placed thereon and a mechanism for transferring the fruit to a container for later transportation. As with the Olmo patent, this device comprises a device for guiding, supporting and moving the paper strip towards the rear of the machine. U.S. Pat. No. 4,221,665 to Decker describes a raisin harvesting apparatus that is configured for picking up raisin paper trays and depositing the raisins into bins. This apparatus has a rearward disposed fork mechanism which slides under the paper trays, a draper web situated above the fork for engaging the trays and sliding them along the fork to a conveyor mechanism that transfers the raisins to a receptacle. Workers standing on the running boards of the apparatus remove the raisins from the paper trays, which are impaled upon spikes for later disposal. U.S. Pat. No. 4,759,680 to Simpson, III describes an apparatus for separating a crop from a continuous paper tray that comprises a first conveyor that engages and transports the paper tray, having the crop thereon, to a second conveyor. The second conveyor engages and inverts the paper tray to dislodge the crop onto a third conveyor, which is placed in receiving relation to the second conveyor to receive the crop and then transport it to a collection point. U.S. Pat. No. 5,042,240 to Rocca, et al. describes a crop recovery apparatus comprising a first conveyor configured to receive and convey the continuous paper tray, a second conveyor moving with the first conveyor and configured to overlay the paper tray and crop on the first conveyor, finger members which maintain the space between the two conveyors, a vacuum system for removing debris and a folding mechanism that folds the first conveyor downward so the crop thereon will fall onto a third conveyor for conveyance to a receptacle.
Although the prior art does describe several harvesting apparatuses for picking-up continuous paper trays having crop thereon and separating the crop from the paper tray for transport to a raisin bin or other receptacle, each of the foregoing has limitations which have prevented their full acceptance for use with the continuous paper tray method of harvesting crops. What is needed, therefore, is an improved apparatus for picking up and separating raisins or other crops from a continuous paper tray. The preferred harvesting apparatus will be configured to move over the ground between two adjacent rows of plants, collect a continuous paper tray placed on the ground with crop placed on the paper tray, separate the crop from the paper tray and then convey the crop to a bin or other receptacle. Preferably, the harvesting apparatus will accomplish the above tasks with minimal input from laborers other than the operator of the apparatus. The preferred harvesting apparatus will be configured so as to be economical to manufacture and operate.