1. Field of the Invention
This invention relates to and has among its objects the provision of novel apparatus for harvesting vegetable heads which are non-colinear with respect to the stalk line in a row of heads. Further objects of the invention will be evident from the following description wherein parts and percentages are by weight unless otherwise specified.
2. Description of the Prior Art
Vegetable heads, such as cauliflower or cabbage, grown in the United States are presently harvested manually. The harvesters select the head to be harvested by visual observation according to size. The head is then manually cut and thrown into a suitable receptacle, e.g., a trailer drawn by a tractor.
Manual harvesting is fraught with disadvantages such as large consumption of time and expense, inevitable spoilage of mature vegetable heads, etc. For example, during peak growth periods a sufficient number of workers cannot be obtained to pick a cauliflower crop. As a result, the cauliflower heads, which can become over-mature one-day after they are ready for harvest, are lost as a salable product.
Mechanical means for harvesting lettuce heads are known and described in U.S. Pat. Nos. 3,300,954, and 3,300,955. In the known apparatus the maturity of the head is determined by compression rollers, one fixed and the other laterally movable. The compression rollers are composed of a plurality of cylindrical rollers mounted on shafts and projected downwardly. The compression rollers form a V-shaped configuration. A mature lettuce head will laterally displace the movable compression roller thus triggering a cutting mechanism which cuts the mature lettuce head. The cutting mechanism includes a pair of knife baskets vertically rotatable. Each knife basket is equipped with a knife and a basket or cradle portion. The knife severs the lettuce head and the cradle portion conveys the harvested head to a container.
Although the known harvester works well for harvesting lettuce heads, it cannot be used for harvesting vegetable heads such as cauliflower and cabbage. A mature head of cauliflower, for example, is composed of a center or head of cauliflower engulfed in an abundance of large, loose-fitting leafy material. Thus, the cauliflower head is quite different from a lettuce head which is composed of leaves of lettuce tightly formed into a ball-like shape. Cauliflower and cabbage plants also have longer stems and grow further out of line from the row in which they are planted than do lettuce plants. That is to say certain of the heads ar non-colinear with the stalk line in a particular row. Generally, the stalks of the plant remain in a straight line corresponding to that formed when the seeds are planted. The plants, themselves, however, grow out of this stalk line, i.e., they are non-colinear therewith. Lettuce heads, on the other hand, will grow colinearly within the row.
The leaves surrounding the cauliflower and cabbage heads cause the known harvester to function improperly by fouling the compression rollers. In addition, the known selector cannot align itself with non-colinearly growing vegetable plants because one compression roller is fixed. Furthermore, the cutting mechanism is not adequate to sever mature heads of cauliflower or cabbage with their bulky leaf package.