The
Challenge:
A customer in the beverage
industry required an economical linear positioner for beverage
handling equipment. This unit would be subjected to highly caustic
chemical wash-downs and also be required to satisfy a very demanding
motion profile:
- 3g acceleration to 120 inches per second, followed by a 3g
deceleration;
- 48” cycle per second;
- 24 hours operation - 365 days per year.

The Solution:
A Daedal belt driven round rail table was designed utilizing (2)
316 stainless steel bearing shafts combined with phenolic sleeve
type bushings to form the support bearing assembly. The bushing
housings were "self aligning", to enable the bushings to pivot about
their centers adjusting for any misalignment between bushings on
each shaft.
On subsequent units, Daedal designed
a FR4 glass filled phenolic substitute for 316 stainless and
aluminum in the bushings and other construction components to reduce
costs (this material is is about ¾ the cost of 316 stainless) as
well as satisfy the caustic environment condition. This material
demonstrate machining and strength properties comparable to aluminum
and has chemical
resistance properties similar to 316 stainless.

The prototype unit successfully
completed rigorous life testing (over 3 million cycles) to assure
that the desired performance would be achieved. Since then,
production units have installed and operating successfully for over
18 months, requiring only routine maintenance after six months of
continuous operation. |