PRIOR ART AND BACKGROUND OF THE INVENTION
Oranges and grapefruit have been packaged in bags at the shipping point more than three decades in Florida. For about twenty years it was all done manually. Only fabric mesh bags were used before polyethylene film bags, which first appeared in Florida statistics for the 1958-59 season. Polyethylene net bags first appeared in Florida statistics for the 1966-67 season.
In Flordia most citrus bagging in polyethylene film bags is done by semiautomatic machinery; limited automatic machines are in used. In all semiautomatic bagging operations, purchased (premanufactured) bags are used entirely. The semiautomatic equipment used by the larger portion of the packinhouses counts the desired quantity of fruit into the bag upon actuation of a foot pedal or other control by the operator. The operator holds the bag in position to catch the fruit, then closes it by a tape or stapling device, and places it in a master carton. Similar semiautomatic equipment is used elsewhere for packaging such produce as apples, onions, and potatoes in polyethylene film bags. Generally, this equipment measures quantity by weight instead of count. Machine action or the operator pours the measured quantity from a pan or accumulating chamber into the bag after the machine feed has stopped at a preset weight. Bag closing practices are similar to those employed on semiautomatic citrus bagging operations. Semiautomatic machines suitable for polyethylene film bags are also generally usable for bagging fruit in polyethylene net bags.
Automatic polyethylene film bagging machines have been installed in several Florida packinghouses over approximately the past three years. Premade bags are used by all of them except for one make that uses specially prepared film, doubled, in a ribbon with perforations in heat-sealed strips between bags. The bagging machine heat-seals the top after filling except where twist-tie or Kwik-lok closing has been substituted. Bags separate along perforation lines in passing out of the machine onto the takeaway conveyor. Manual checking of bag weight is required in operating one make of these machines, a carrousel type.
No fully automatic machines are available for handling polyethylene net bags except one type, recently offered in the Florida citrus area, with an attachment for automatically handling net bags supplied on wickets. Thus far, the tooling of bagmakers has not provided for supplying polyethylene net bags in this way. Even if manufacturers were to supply these bags on wickets, the price of the bags might be higher than that for net bags supplied in the usual manner.
Manufactured polyethylene net bags cost about twice as much as film bags. Economic advantages would accrue to consumers and packers alike by having bag forming incorporated into an automatic cycle of bag filling and closing, as in the experimental machine.
Testing of the machine was confined to packing 5-pound bags of oranges because of their lead in shipments of Florida citrus fruit in polyethylene net bags. The machine is adaptable, however, to other bag sizes, produce, and applications.
This machine has the following objectives: (1) It eliminates the need for preformed bags in the citrus packaging industry. (2) It enables previous equipment to operate totally automatically. (3) Bag forming can be incorporated into an automatic packaging cycle. (4) It eliminates the need for manual labor. (5) It reduces considerably the cost of packaging citrus fruit. (6) It can be used for other types of produce as well as citrus fruit. (7) It holds the polyethylene material in position during fabrication of the bag. (8) It positions and holds the bag during the produce filling operation.
FIG. 1 is an isometric exploded view showing the lower portion of the bagging machine. Section AA is the opening and gripping mechanism portion of the bagging machine and is the same as FIG. 2.
FIG. 2 is an isometric view of the opening and gripping mechanism in the opening and gripping position.
FIG. 3 is an illustrative view of the opening and gripping mechanism in the open and closed position.
Reference is made to illustrative drawing FIGS 1, 2, and 3. The opening and gripping mechanism operates in conjunction with an automatic produce bagging machine that uses factory-roll polyethylene net tubing. The opening and gripping mechanism can be seen in relation to the bagging machine by referring to FIG. 1 section AA.
Air cylinders 19 are attached to cylinder rod 25, FIG. 2, which is attached to pivot block 3, FIG. 2, using connecting screw 4, FIG. 2, which is attached to crossed members 1 and 2. The forward ends of cross members 1 and 2 have cylindrical vertical gripping fingers 26, FIG. 2, attached at 90° angles to said cross members 1 and 2. The aft end of cross members 1 and 2 are secured by slide action bushing 31, FIG. 3, and a screw through the cross member. Cross member 2 has a spacer 30, FIG. 2, on the secured aft end. This spacer 30 is slightly thicker than the cross member 1. It is the function of this spacer to allow for horizontal leveling of cross member 2.
Since it is the basic function of the gripping surfaces to grip and hold the polyethylene bagging in place during the automatic machine cycle, this operation takes place as follows: air cylinders 12 are actuated forward. This causes cylinder rod 25, FIGS. 2 and 3, to move forward. Since it is attached to pivot block 3 which is attached to cross members 1 and 2 at 2/8 inches forward of the center of the cross bar by screw 24, the forward end with the gripping fingers 26, FIGS. 2 and 3, moves forward to the center of frame 27, FIGS. 2 and 3, aligning themselves in the entry position 33, FIG. 3. Simultaneously, the aft secured end rides the slide action bushing 31. FIG. 3, along slots 28, FIG. 3, such that the aft ends come together in alignment, thus completing a closing cycle.
The opening cycle takes place by the direct reverse of the operation described above. Air cylinders 12 move rod 25, FIGS. 2 and 3, backward causing gripping fingers 26, FIGS. 2 and 3, to move backward bringing gripping fingers 26 and gripping surface 29, FIGS. 2 and 3, together with the polyethylene net tubing held firmly between fingers 26 and gripping surface 29, FIGS. 2 and 3, thus completing a full open and closing cycle.
The entire gripping head assembly is capable of being lowered and raised during the bag-forming cycle of the automatic bagging machine.