FIELD OF THE INVENTION
This invention is directed to nesting containers such as bottles on a moving conveyor and reducing the number of gaps between bottles that tend to form when the bottles are nested on the conveyor. After nesting the containers, the nested containers are moved on a conveyor to a film wrapping station and then to through a heat shrink tunnel to shrink the film to form a bundle of containers.
SUMMARY OF THE INVENTION
The objective of the invention is to accumulate the bottles in a nested formation at a high speed on a moving conveyor and the reduction or elimination of gaps between the bottles that are caused by missing bottles. The is done by oscillating the conveyor belt
Another objective of the invention is to accumulate a predetermined number of bottles in rows to be bundled by establishing a first barrier to retain the bottles on the conveyor and using second barrier to control the number of rows to be included in the bundle.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1 and 2 show containers on a moving oscillating conveyor pressing against a first barrier causing the containers to form a nested arrangement.
FIG. 3 shows a blown of view of the first and second barriers with the oscillating guides.
FIG. 4 shows a finger of the second barrier in a bottle.
FIG. 5 shows a second barrier.
FIG. 6 shows a scalloped first barrier.
DETAILED DESCRIPTION OF THE INVENTION
This invention is directed to making bundles of containers that can be placed on pallets. Depending on the size of the containers the dimension of the bundle can be approximately 1/16 to ½ of pallet. FIGS. 1 and 2 show transporting containers 2 resting on a moving oscillating conveyor belt 3 of an in feed conveyor 1. The containers are moved against a first barrier causing the containers to form a nested arrangement. The nested containers 2 form gaps where containers can be missing. To reduce or eliminate the gaps the containers can be shaken by oscillating side guides or by oscillating the conveyor belt 3. An oscillation of about 0.5 inch is usually sufficient to reduce or eliminate the gaps. The preferred embodiment is to oscillate the moving conveyor belt 3. This can be accomplished by using two oscillating side guides 18 and 19 located on each side of the belt to move the conveyor belt sideways by pushing the conveyor belt back and forth while the adjustable guides keep the containers on the conveyor belt in a stable condition. The adjustable side guides have enough play to accommodate the movement of the belt and still maintain stability of the containers. The conveyor belt can be rigid or flexible. If a rigid belt is used the belt and the belt pulleys at each end of the conveyor will have to move sideways as a unit. The preferred embodiment is to use a flexible belt such as made by Regina under the name Matveyar to avoid having to move the pulleys. This belt is made of small plastic elements that allow the oscillating side guides 18, 19 to move the belt sideways under the containers without moving the pulleys.
FIG. 3 shows the oscillating guides 18, 19 almost parallel to the plane of the conveyor belt. The adjustable guides 13 are above the oscillating guides 5
Figure one and two show a oscillating conveyor belt 4 moving the containers 2 on an in feed conveyor toward a first barrier 6. First barrier 6 stops the containers from moving on the conveyor and allows the containers to nest and form rows as they accumulate against the first barrier 6. To form the nesting, the first barrier 6, as shown in FIG. 6, can be a flat plate having scallops to accommodate the diameter of the containers. The moving conveyor forces the containers into the scalloped plate causing a nested arrangement. The preferred embodiment is to manually place a number of rows of containers in a nested arrangement against a flat first barrier before the conveyor begins to run. Three nested rows of manually placed is sufficient to initiate the nesting of the moving containers. This alleviates the need to replace the first barrier with scallops to accommodate containers having a different diameter. After a predetermined number of rows of the containers have accumulated against the manually placed rows pressing against the first barrier 6, a second barrier 5 having fingers 10, shown in FIG. 5, is inserted between the last row of the predetermined number of containers and the first row of the next predetermined number of containers to stop the movement of the containers. When the containers are of sufficient diameter the fingers are inserted in a vertical position between the rows of containers into the diamonds formed by the nested containers. Usually there will be one finger for every other container in the row. After the second barrier is inserted, the first barrier is moved to release the predetermined number of rows of nested containers trapped between the barriers. Usually the movement of the first barrier 6 is delayed until at least a sufficient number of rows to make about two bundles of containers behind the second barrier. The released rows of containers are conveyed to the forming head 7. A square motion pusher having a scallop pusher plate to accommodate the structure of the nested bottles sits above the height of the bottles. After the bundle has gone passed the pusher to the forming head, the pusher will lower and push the bottles through the forming head 7 and over the seal bar 1. Then the square motion pusher retracts to its previous position by rising back up so the next bundle can pass underneath. At the forming head 7, the predetermined number of rows of containers is film wrapped with film 17 into a bundle. Sealing bar 11 seals the rear of the bundle. Then the bundle is transported to a heat shrink tunnel 9 to shrink the film.
The position of the second barrier with respect to the first barrier needs to be adjusted to accommodate containers having various diameters. This achieved by adjusting the distance between the first and second barrier. To achieve this adjustment the second barrier is mounted as shown in FIG. 3 that allows the second barrier to be moved horizontally. Using a screw with a stepper motor or a servomotor, the second barrier can be horizontally positioned to the desired distance from the first barrier.
The desired distance between the barriers can be calculated by using the diameter of the containers and the desired number of rows of containers. This can be done manually or by a conventional sensor such as optical sensor or a capacitance sensor or a clamp potentiometer that can provide the diameter of a sample bottle and sends the data to a computer that calculates where the second barrier has to be positioned in relation to the number of rows to achieve the desired number of rows to be bundled. The computer can send a signal to the servo motor or stepper motor to move the barrier to the correct position. A photo cell 12 or a vision system can be used to check the exact position of the last bottle in the row and if needed to provide data to a computer that will provide a signal to move the second barrier to the correct position.
When the containers are empty bottles and the diameters of the bottles are small such as 19 to 25 mm there is almost no room to insert the fingers of the second barrier. In this situation the barrier 5 has fingers 10 to accommodate every other bottle. FIG. 4 shows the finger 10 inserted inside the upper opening of the bottle 2. The fingers are inserted at an angle and will stop against the inside body of the bottle. The insertion of the finger 10 into a bottle needs be controlled to accommodate the shape of the bottle. If the bottle is high and the fingers rest on the inside the neck of the bottle, the bottle can become unstable and tip. To adjust for different types of bottles, a sensor such as potentiometer sensor, having a moving vertical plate, can be used determine the height of a sample bottle and send a data to a computer that can create a signal to adjust the stroke length of the second barrier. A servomotor or a stepper motor can be used to change the stroke length of the finger. The first or second barrier is generally coated with a Teflon or a ceramic coating.
By sensing the diameter of the containers the computer can automatically calculate the distance between the barriers and automatically adjust to accommodate the number of rows between the barriers.
Patent Grant
8806841
