Abstract:
An apparatus and method for harvesting cranberries, the method including moving frame-mounted transverse dislodging rods over cranberry plants with each rod moving at the speed of the frame, thereby to dislodge cranberries from the cranberry plants. The apparatus includes a plurality of dislodging rods secured below the frame, the dislodging rods positioned substantially parallel to the field surface and generally perpendicular to the direction of movement whereby each dislodging rod is moved through the cranberry plants at the speed of the frame to dislodge the cranberries from the plants. Certain preferred embodiments use follower assemblies to configure an array of dislodging rods in an advantageous arrangement.

Description:
FIELD OF THE INVENTION 
   This invention is related to cranberry harvesting and, more particularly, to cranberry-harvesting equipment and methods. 
   BACKGROUND OF THE INVENTION 
   Cranberries are raised in fields or bogs, which are relatively flat areas divided into sections so that the fields can be flooded both to facilitate harvesting and to protect the vines from frost. The cranberry plants form a mat of vines which may be up to twelve or fourteen inches deep. During harvesting, the berries are removed from the vines and float to the surface of the water. The berries are then gathered up for transport to a processing facility. 
   Traditional methods of harvesting cranberries and the equipment used to implement such methods generally fall into two categories. Both traditional methods have drawbacks which will be described herein later. 
   The first general method can be characterized as “beating” and is carried out using equipment which includes beaters which are bars mounted on combine-like revolving structures. U.S. Pat. No. 3,672,140 (Burford) discloses equipment based on this principal. As the harvesting vehicle moves through the cranberry bog, a rotating wheel with transverse bars to agitate the cranberry vines, causes the cranberries to detach from the plants. The rotation of the wheel causes the transverse bars to move through the cranberry vines at a speed greater than the vehicle speed at the position of principal contact with the plants. Cranberries float to the surface of the flooded bog and are gathered up. U.S. Pat. No. 4,501,111 issued to Abbott describes another harvester unit which uses such a rotating wheel approach. 
   The second general method can be characterized as picking or raking. U.S. Pat. No. 2,524,631 (Minutillo) describes a harvesting machine based on this method. A series of combs mounted on a rotating wheel is moved through the cranberry plants to detach the cranberries from the vines. U.S. Pat. No. 5,067,047 (Rosset) discloses harvesting equipment which employs vertically-oscillating tines to strip the cranberries from the vines. Rosset then collects the stripped cranberries through a vacuum suction unit. 
   As mentioned above, the methods and equipment which are used for cranberry harvesting have certain drawbacks. As in any commercial endeavor, increased productivity is in general a desired performance. Typical harvesting rates for the cranberry-harvesting equipment commonly used today is on the order of 0.5 acres per hour, with maximum rates being about 1.5 acres per hour. Productivity is also affected by the fraction of the fruit which is removed from the vines during harvesting. A higher fraction yields higher productivity. 
   Some of this equipment is quite “aggressive” in how it treats the cranberry plants, often resulting in damage both to harvested fruit as well as the vines. In addition, much of the equipment used today includes a number of moving parts, often driven by hydraulic equipment. The operation of hydraulic equipment during harvesting creates the risk of the fruit becoming contaminated with hydraulic fluid. Also, the complexity of the equipment translates into increased maintenance cost. 
   Finally, for cranberries which are sold as fresh fruit rather than processed into juice or other consumer food products, not only is it advantageous to prevent damage to the fruit, it is also of great benefit to avoid wetting the fruit during harvesting. As mentioned above, the fields or bogs are flooded, allowing the fruit which has been separated from the plants to float, thereby facilitating the collection of the fruit. However, the fruit, being now wet, is subject to the growth of fungus or requires the additional costly step of drying in order to deliver fresh, unblemished fruit to the market. Because of this, it is advantageous to dry-harvest cranberries to avoid these problems or costs. 
   Therefore, there is a need for simple, rapid and efficient, low-cost method and apparatus to harvest cranberries. 
   OBJECTS OF THE INVENTION 
   It is an object of this invention, in the field of cranberry-harvesting, to provide a cranberry-harvesting apparatus and method which harvest cranberries at substantially higher rates (acres per hour) than existing harvesting equipment and methods. 
   Another object is to provide cranberry-harvesting apparatus which is mechanically simple and requires a minimum of maintenance. 
   Another object is to a provide cranberry-harvesting apparatus and method which remove a higher fraction of the cranberries from the vines than existing harvesting equipment and method. 
   Another object is to provide cranberry-harvesting apparatus which can be both pushed or pulled through the field of cranberry vines. 
   Another object is to provide cranberry-harvesting apparatus which reduces the risk of contamination of the fruit being harvested. 
   Still another object is to provide cranberry-harvesting apparatus which reduces the damage to the cranberries being harvested. 
   Yet another object is to provide a cranberry-harvesting apparatus and method which can be used for both wet and dry harvesting of cranberries. 
   These and other objects of the invention will be apparent from the following descriptions and from the drawings. 
   SUMMARY OF THE INVENTION 
   The invention is a method and apparatus for harvesting cranberries, whereby frame-mounted transverse dislodging rods are moved over cranberry plants with each rod moving at the speed of the frame, thereby dislodging cranberries from the cranberry plants. The cranberry-harvesting apparatus of this invention comprises a frame movable over a field of cranberries in a forward direction with a plurality of follower assemblies each secured to and below the frame by a support. Each follower assembly includes: a rod mount having a lower portion, a surface-following leading end, and a pivot attachment to the support at the lower portion behind the center-of-gravity of the follower assembly; and first and second pairs of dislodging rods mounted to the rod mount forward and rearward of the pivot attachment respectively, each pair extending laterally from opposite sides of the lower portion substantially parallel to the field surface and canted rearwardly. Each rod mount is supported such that it moves through the cranberry plants at the speed of the frame to dislodge the cranberries from the plants. 
   In certain highly preferred embodiments of the inventive cranberry-harvesting apparatus, the first and second pairs of dislodging rods are spring-mounted such that the dislodging rods deflect under load in a plane substantially parallel to the field surface. 
   In another preferred embodiment of the cranberry-harvesting apparatus, each rod mount is a vertical plate having spring posts extending downward to the lower portion, and each dislodging rod has a coiled proximal end forming a spring coiled around one of the spring posts. Certain preferred embodiments of such apparatus further include feet extending from the lower portion rearwardly below each pair of spring posts for the purpose of reducing the entanglement of plants with the spring posts. In another preferred embodiment of the apparatus, the dislodging rods have a substantially circular cross-section. 
   In highly preferred embodiments of the cranberry-harvesting apparatus, the frame has a major axis generally perpendicular to the movement thereof and parallel to the field surface. Each dislodging rod has a free distal end, and the follower assemblies are laterally spaced substantially equally along the major axis in alternating forward and rearward positions thereby forming offset forward and rearward gangs of adjacent assemblies such that the distal ends of the dislodging rods of adjacent assemblies overlap along the major axis. The distal ends of the dislodging rods of adjacent assemblies of each gang are spaced apart along the direction of movement. In certain other embodiments of the inventive cranberry-harvesting apparatus, the space along the direction of movement between the dislodging rod distal ends of adjacent follower assemblies is at least four inches. 
   In highly-preferred embodiments of the cranberry-harvesting apparatus, the frame includes a principal cross-member, and each support includes a longitudinal arm pivotably mounted to the cross-member. 
   In some embodiments of the cranberry-harvesting apparatus, each longitudinal arm is downwardly spring-biased against the field surface. In such embodiments, it is most preferred that such apparatus include: an anchor arm affixed to the cross-member and having a first connection spaced therefrom; a second connection on the longitudinal arm spaced from the cross-member; and a spring linkage between the first and second connections such that the longitudinal arm moves under load with respect to the anchor arm to provide the downward biasing. In some embodiments, each surface-following leading end is substantially convex. 
   In other embodiments of the cranberry-harvesting apparatus, the frame is operator-movable up and down such that the surface-following leading ends can be positioned in and out of contact with the field surface. 
   In another preferred embodiment of the inventive apparatus, the space between the first and second pairs of dislodging rods is at least twelve inches. In addition, in some preferred embodiments, the cant angle of the dislodging rods is between 15 and 40 degrees from the major axis. 
   Some highly-preferred embodiments of the invention further include a drive apparatus to move the frame over a field of cranberries. In some embodiments, the frame is mounted to the front of the drive apparatus, and in other embodiments, the frame is mounted to the back of the drive apparatus. 
   Certain embodiments of the cranberry-harvesting apparatus include at least one vacuum nozzle behind the follower assemblies whereby the dislodged cranberries are picked up by vacuum suction. Some embodiments include a vacuum nozzle behind each of the follower assemblies. A collection container may also be included in such apparatus. 
   Broadly considered, the inventive cranberry-harvesting apparatus includes a frame movable over a field of cranberries in a forward direction and a plurality of dislodging rods secured to and below the frame. The dislodging rods are positioned substantially parallel to the field surface and substantially transverse to the direction of movement such that each dislodging rod is moved through the cranberry plants at the speed of the frame to dislodge the cranberries from the plants. 
   The inventive method for harvesting cranberries from a cranberry field includes moving frame-mounted transverse dislodging rods over cranberry plants with each rod moving at the speed of the frame to dislodge cranberries from the cranberry plants. One form of the inventive method of harvesting cranberries includes moving frame-mounted transverse dislodging rods over cranberry plants in a non-flooded field, thus moving each rod at the speed of the frame to dislodge cranberries from the cranberry plants, resulting in dry-harvesting of the cranberry fruit. Certain preferred embodiments of the inventive method further include the steps of vacuuming up dislodged cranberries immediately after dislodgement and collecting the cranberries in a collection container. 
   As used herein, the following terms have the meanings given below, unless the context requires otherwise. 
   The term “field surface” refers to the surface of the cranberry field from which cranberries are being harvesting. Most typically, this will be the upper surface of a mat of cranberry vines (rather than the surface of the soil) which are being compressed by the follower assemblies as such assemblies are biased downwardly and moved over the cranberry field. 
   The term “surface-following” is used herein to describe one function of the leading end of a follower assembly, indicating that the leading end enables the follower assembly to move over the field surface in a path which conforms to the contour of the field surface without digging into the field surface or becoming entangled with vegetation. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of one embodiment of the inventive cranberry-harvesting apparatus. 
       FIG. 2  is a side elevation of the embodiment shown in  FIG. 1 . 
       FIG. 3  is top plan view of the embodiment of  FIG. 1  with the first-from-the-left of the longer longitudinal arms partially removed to show the overlapping distal ends of neighboring dislodging rods. 
       FIG. 4A  is a detailed side elevation of a portion of one embodiment of a rod mount. 
       FIG. 4B  is a top plan view of the rod mount shown in  FIG. 4A . 
       FIG. 5  is a side elevation of the inventive apparatus, including drive apparatus to pull the frame over the field of cranberries. 
       FIG. 6  is a side elevation of the inventive apparatus, including drive apparatus to push the frame over the field of cranberries. 
       FIG. 7  is a side elevation of the inventive apparatus shown in  FIG. 5  further including one vacuum nozzle behind each of the follower assemblies and a collection container. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 1 ,  2   3 , and  5  show a cranberry-harvesting apparatus  10  which is one embodiment of this invention. Apparatus  10  is configured to be pulled over a cranberry field. Apparatus  10  has a frame  20  which is pulled over a cranberry field in the direction indicated in  FIG. 1 . Apparatus  10  includes ten follower assemblies  22  configured in a forward gang  24  of follower assemblies  22  and a rearward gang  26  of follower assemblies  22 . Cranberry-harvesting apparatus  11  of  FIG. 6  is configured to be pushed over a cranberry field. This invention is described primarily with reference to apparatus  10 ; as will be apparent, the two embodiments are substantially similar to each other in their essential elements. 
   Frame  20  consists primarily of a principal cross-member  28 . Each follower assembly  22  is attached to frame  20  by a support  30  (ten supports  30  for ten follower assemblies  22 ). In  FIG. 1 , five supports  30  are short and five are long, supporting gangs  24  and  26  respectively. Each support  30  includes an anchor arm  36  rigidly connected to principal cross-member  28 , a longitudinal arm  32  which is pivotally mounted to anchor arm  36  by a pivot mount  34  located within anchor arm  36  near cross-member  28 , a follower mount  48  affixed to longitudinal arm  32 , a follower pivot  50  within follower mount  48  spaced away from longitudinal arm  32 , and a spring linkage  38 . 
   Follower assembly  22  is pivotally connected to follower mount  48  at a point within follower assembly  22  such that the center-of-gravity of follower assembly  22  is forward of follower pivot  50 . Anchor arm  36  includes a first connection  40  spaced away from principal cross-member  28 . Longitudinal arm  32  includes a second connection  42  also spaced away from cross-member  28 . Spring linkage  38  is pivotally connected to first connection  40  and second connection  42  such that longitudinal arm  32  is able to pivot around pivot mount  34  as the contour of the field surface changes. Spring linkage  38  exerts a force such that follower assembly  22  is pushed downwardly onto the field surface. 
   Referring to  FIGS. 1 and 2 , each follower assembly  22  includes a rod mount  44  which is comprised of a vertical plate  46 , four spring posts  62  affixed to plate  46  (plate  46  and posts  62  are a preferably a weldment), a first pair  52  of dislodging rods  60  positioned forward of follower pivot  50  and a second pair  54  of dislodging rods  60  positioned rearward of follower pivot  50 . Vertical plate  46  includes a convex surface-following leading end  56  and a lower portion  58 . Follower pivot  50  is positioned at lower portion  58 , and as noted above, behind the center-of-gravity of follower assembly  22  such that follower assembly  22  moves over the field surface substantially parallel to the field surface. 
   Referring to  FIGS. 4A and 4B , each dislodging rod  60  is mounted to vertical plate  46  by one of the spring posts  62  at a proximal end  64  of dislodging rod  60 . Dislodging rods  60  typically have a circular cross-section as shown in  FIGS. 4A and 4B . Proximal end  64  is formed into a coil spring  65  wrapped around spring post  62 , thereby enabling dislodging rods  60  to deflect in a plane substantially parallel to the field surface under the load exerted by the cranberry plants on dislodging rod  60  as follower assembly  22  is moved over the field surface. 
     FIG. 3  is a top plan view of apparatus  10 , illustrating the configuration of follower assemblies  22  into forward gang  24  and rearward gang  26 . The leftmost follower assembly of rearward gang  26  is partially removed from  FIG. 3  to illustrate the relative positions of dislodging rods  60  of neighboring follower assemblies within forward gang  24 . Frame  20  has a major axis  70  which is generally perpendicular to the direction of motion of apparatus  10 . Each dislodging rod  60  is mounted in an orientation canted at an angle θ with respect to major axis  70  as indicated on the leftmost and forwardmost dislodging rod  60  in  FIG. 3 . Angle θ is preferably set within the range of 15 to 40 degrees, most preferably about 25 degrees. 
   Each dislodging rod  60  has a distal end  66 , and follower assemblies  22  are positioned within gangs  24  and  26  such that distal ends  66  of neighboring follower assemblies  22  overlap an amount sufficient to ensure that all of the cranberry plants are influenced by dislodging rods  60  as apparatus  10  is moved over the field surface even when dislodging rods  60  are deflected backwards under the load of the cranberry plants. Neighboring dislodging rods  60  of adjacent follower assemblies  22  within gangs  24  and  26  are positioned along the direction of motion with a distance d 1  between distal ends  66  such that cranberry plants which may become caught up on dislodging rods  60  are shed off distal ends  66  as apparatus  10  moves forward over the field surface. Distance d 1  is preferably at least four inches. 
   Each follower assembly  22  has first pair  52  and second pair  54  of dislodging rods  60 , first pair  52  being positioned forward of second pair  54  by a distance d 2 . Distance d 2  is preferably at least 12 inches and more typically between 16 and 18 inches. Distance d 2  is chosen to be sufficient to allow the cranberry plants which are compressed by first pair  52  to rise up before being compressed again by second pair  54 . Distance d 2  is therefore dependent on the speed of the forward motion of apparatus  10 . High speeds require d 2  to be larger. (Distance d, may be about half of distance d 2  or may be significantly less as shown in  FIG. 3 .) 
   The distance between forward gang  24  and rearward gang  26  of follower assemblies  22  is typically larger than distance d 2  to ensure that forward gang  24  and rearward gang  26  act on the cranberry plants in an independent fashion. 
   Referring again to  FIGS. 4A and 4B , each rod mount  44  further includes two feet  68  which extend rearwardly from lower portion  58  of vertical plate  46  below first pair  52  and second pair  54 . The function of feet  68  is to prevent the entanglement of cranberry plants in spring posts  62  and coil springs  65  as apparatus  10  moves over the field surface. Each foot  68  has a tapered front portion  72  to ease movement through the cranberry plants and an open rear portion  74  to release entangled plants. 
     FIGS. 5 and 6  are side elevations simply illustrating the fact that the inventive cranberry-harvesting apparatus can be both pulled ( FIG. 5 ) and pushed ( FIG. 6 ) over the field surface by a drive apparatus  80 , typically a farm tractor suitably configured to drive over a cranberry field. Illustrated in both  FIGS. 5 and 6 , the harvesting apparatus is attached to drive apparatus  80  on a movable hitch  82 . Movable hitch  82  is the standard movable hitch typically available on farm tractors to raise and lower farm implements for proper operation. In addition, frame  20  is able to be rotated on hitch  82  by hydraulic actuator  84  acting on frame arm  86 , further enabling the height and orientation of apparatus  10  and  11  to be adjusted for proper operation. For example, in apparatus  11  in  FIG. 6 , follower assemblies  22  are mounted in the opposite direction from that of apparatus  10  with respect to frame  20  and supports  30 . 
     FIG. 7  is a side elevation of the embodiment of  FIG. 5  configured for dry harvesting of cranberries. Each follower assembly  22  has mounted immediately behind it a vacuum nozzle  88  connected to vacuum unit  90 . Cranberries which are picked up by vacuum unit  90  through vacuum nozzles  88  are deposited into collection container  92 . 
   The general operation of the apparatus  10  is as follows. Apparatus  10  is lowered down onto the field surface such that follower assemblies  22 , primarily through dislodging rods  60 , compress the cranberry plants from an uncompressed thickness, which is typically on the order of twelve inches, down to a thickness of a few inches. Apparatus  10  is moved forward over the field surface, thereby moving dislodging rods  60  over the field surface at the speed of apparatus  10 . As dislodging rods  60  compress the cranberry plants, the cranberry fruit is dislodged from the cranberry plants with a minimum of damage to both fruit and vines. One mechanism by which this dislodging takes place is a squeegee-like action on the field surface. Except those areas covered by the left and right sides of apparatus  10 , every point along the field surface is in general acted on by four dislodging rods  60 , thereby providing significant opportunity for the cranberry fruit to be released from the cranberry plants. 
   Typically, apparatus  10  is moved forward over the field surface by drive apparatus  80  at speeds of five or six miles per hour, thereby being able to harvest approximately three acres of cranberries per hour. High-speed harvesting using the inventive apparatus may be carried out in flooded cranberry bogs, with subsequent cranberry recovery carried out using standard methods known in the art for the gathering of floating berries. 
   Apparatus  10  is able also to be used for dry harvesting of cranberries such that at least a substantial portion of the crop is harvested without being wetted. During dry harvesting, vacuum nozzles  88  mounted immediately behind follower assemblies  22 , are used to pick up the cranberries which have been dislodged by dislodging rods  60 . Since some of the dislodged cranberries may be trapped within the cranberry plants during dislodgement and vacuuming, the cranberry field may then be flooded and the typical methods for the gathering of dislodged cranberries in flooded fields used to complete the harvest. 
   While the principles of this invention have been described in connection with specific embodiments, it should be understood clearly that these descriptions are made only by way of example and are not intended to limit the scope of the invention.