Sharp Packaging Systems has introduced its first vertical
form fill and seal (VFFS) machine, called the Hawk Evolution. It can make a bag up to 12” wide and 18” long. Its motor is a Kollmorgen
stepper motor, which is maintenance free, and designed to run for hundreds of millions of
cycles with little to no maintenance. The Hawk Evolution accommodates three bag styles: pillow bag, typically used in the
potato chip industry; a gusseted bag; and a flat bottom bag, commonly used for coffee in
one pound packages. It will run and seal just about any structure of polyethylene, laminated
or metalized film, or foil. Businesses that use the Hawk Evolution for packaging include
companies that manufacture or process candy, nuts, salted snacks, IQF (individually quick
frozen) foods, pet food, fresh produce, hot foods like soup and gravy, and coffee. There are
also applications for the medical industry.
A double stack Kollmorgen stepper motor operates the jaw drive mechanism. This motor is
known for its long life expectancy and dependability, and is used in a wide variety of
industries. There are very few moving parts in the drive mechanism for the jaws, so there
are very few parts that could wear out. The only wear parts that would be slotted for routine
replacement are the high speed bearings, which are very easy to change. All of the parts
for the Hawk Evolution are off the shelf, available through a wide variety of distributors.
Also included is a motorized unwind; the spindle on which the roll sits is turned by a DC
motor. This motor aids in feeding the film off the roll, helps to maintain a constant tension
on the film, and reduces stress on the pull belts, allowing for a smooth movement of the
film through the system.
When a bag width change is needed, the Hawk is equipped from the film spindle through
the pull belt mechanism with no tool change features. The forming tubes have quick
release locks for fast, easy changeovers. The pull belt assembly is self-centering, so after
the forming tube change, the pull belts return to the proper position automatically. As a
result, there is less time and material wasted.
The number of printers required is optional, dictated by the particular application. The Hawk
Evolution can accommodate up to 2 printers. The most prevalent printers used are the 53
mil and the 107 mil Videojet printers which have a thermal transfer printing technology to
imprint bar codes, graphics and alphanumerics directly on the package.
The Hawk Evolution is equipped with an edge guide system, a pair of “eyes” that watches
the edge of the film. If the film wanders one way or the other, the eyes communicate with
an air cylinder that will move the whole back stand, so that the film will be centered on the
forming tube. This feature is important to keep the vertical seal in its proper position.
The Hawk Evolution can be customized with a powerful PC based system, which stores
the manuals for the HMI which include troubleshooting video clips to view right on the
computer screen. The operator can pull up a video on how to fix any problem. Videojet or
print label programs can also be stored in the system.
There is an Allen-Bradley PLC (programmable logic controller) in the machine, the
MicroLogix 1400. All of the prime movers have sensors on their openings and closings.
Sensor driven step logic program is used to animate the machine. There are no delays
between steps. As soon as it completes a job, it immediately moves to the next step. This
approach should optimize the machine cycle speed. If a step isn’t completed, a sensor
sends a fault notice to the screen, and the operator knows exactly what happened and
where to look for the problem. It is especially helpful in troubleshooting for wear parts.