Automatic Packaging Machinery - Setting Up Indexing
Automatic packaging equipment, including rinsers, fillers and even some capping equipment, will use indexing systems to properly position bottles for the packaging process taking place. While different indexing systems exist, most automatic machinery will include a quick and simple way to find the correct timing for the system regardless of the indexing used. One of the most common indexing systems is pin, or gate, indexing. Generally speaking, this type of indexing uses an entry gate to allow bottles in to the packaging area and an exit gate to help position the bottles and release them once the process at hand in complete.
A filling machine, for example, will use pin indexing to allow the correct number of bottles in to the fill area, as well as keep them positioned under the heads for the duration of the fill. The entry gate will open to allow bottles in to the fill area, with a count eye ensuring that the desired number pass. Once that number is reached (eight bottles for an eight head filler, for example), the entry gate will close to hold back additional bottles. The exit gate will already be closed, to stop the bottles within the fill area and help to properly line them up under the heads.
The opening and closing of these gates must be timed just right to allow bottles to enter, to allow time for the fill and to allow time for the bottles to exit as well. If the gates do not open and close at the correct times, bottles may jam, spills and splashes may occur, fills will be inconsistent and, overall, the machinery will simply not work efficiently at all. So how do operators ensure that the timing is correct?
While trial and error could be used to calculate the travel times of the bottles, the fill times, the amount of time for head dives and retractions and/or other functions that make up a fill cycle, a much easier way exists to quickly and easily set indexing times. On almost every automatic machine, the operator interface will include a screen that will assist in finding the correct indexing times using a PLC and other pre-sets including the other functions mentioned above. Operators of automatic equipment will simply use the touchscreen interface to navigate to the Auto Set-Up Screen or ASU.
Once on the ASU screen, an operator need only ensure the correct number of bottles will be counted entering the fill area and line up the desired number of bottles behind the entry gate outside of the processing zone, in our example the fill area. (Again, this will typically be four bottles for a four head filler, eight bottles for an eight head filler, etc., though some exceptions do exist). Once this is done, the packager just presses the Start ASU Index on the touchscreen panel and the entry gate will open. The count sensor will keep track of bottles as they pass by the eye and relay this information to the PLC. This process captures an entry gate delay time as well as an exit gate duration time. This info is then incorporated with the other delay and duration times already in the PLC to calculate the necessary times for proper indexing, and saves the times to the machine! Keep in mind that a change in conveyor speed or bottles will require a change in the indexing time!
Once these times are collected for any bottle, they can also be saved as a recipe, for easy recall each time that same bottle is used in production. The ASU screen turns the potentially time-consuming process of finding proper indexing times into a press-a-button solution to keep machinery set up to a minimum and efficient, ensuring more products get packaged during each production day.