Wexxar WF-10T, Operation And Service Manual

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WF-10T Case Former Controls
5-32
5.7
Case Orientation Changes
Corrugated case blanks have an orientation (or ‘handing’), depending on what is sometimes
called the case printing direction. The handing is determined by the orientation of printing on the
longest sides of the case in relation to the relative position of the smaller end panels. There are
two possibilities that are mirror images of each other, and the relationship determines the
direction in which the case is opened. The illustration below shows the difference in relative
position of printing on the major side panel in relation to minor end panels and the Wexxar
definition of matching right-hand and left-hand case erecting machine construction.
In hand erecting of cases, the printing direction is not usually an issue, as the individual who is
forming the case will compensate for the difference by keeping the bottom of the case ‘down’ and
the print upright and readable. However, automatic case forming requires that the case be
erected from the case blank in a consistent left-to-right or right-to-left direction as determined by
the way the cases were printed when they were made. If the erecting order does not match the
printing direction, the only way the cases can be erected on an automatic former is with the
printing, and therefore the formed case, upside down.
Needless to say, case printing direction orientation has been a source of considerable confusion
in matching forming machines to the case blanks that they are intended to erect, and a common
problem in the industry has been the arrival of case samples to test on a completed machine
being of the opposite hand to which the machine was built. Contract packing houses have
usually had to have separate machines of each orientation in order to handle the variation in
customer cases.
The WF-10T case former is not only unique in its use of mechanical case gripping through Pin &
Dome technology to form the case from the bottom, it uses this technology to erect either right-
hand or left-hand cases through a relatively straightforward machine change-over procedure.
The WF-10T manages to handle the different case orientations by gripping the flaps of both
opposing side panels at the same time as it erects the case from the case blank. The
significance of this method is that erecting a right- or left-handed case is primarily determined by
the direction of rotation of the jawplates as the case moves through the machine.