As manufactured goods become more sophisticated, so too do the conveyor
systems that whisk them around the factory floor. These high-end models feature improvements to
drive systems, controls and mechanical components that allow them to handle expensive,
delicate or contamination-prone goods such as solar panels or medical devices.
Here at the Assembly Technology Expo just outside of
Chicago, Bosch-Rexroth showed off a collection of
these advanced conveyor systems.
The company displayed a new conveyor system designed for solar
cell manufacturing. "Solar cell manufacturing is exploding right now, and we
found there were no standards for setting up the manufacturing cells," says
Kevin Gingerich, marketing director for Bosch-Rexroth's Linear Motion and Assembly
That's where the new TSsolar conveyor comes in. Based on the company's
modular TS Conveyors, the TSsolar features modifications intended to protect
delicate wafer- and thin-film solar cells as they make their way through their
multi-step manufacturing processes.
to Gingerich, the conveyor modifications include an upgrade to servo drives,
which can better meet the need for controlled acceleration and deceleration of
the panels. Each segment of the TSsolar features its own drive unit, which all
work in a coordinated fashion to help manage the flow of multiple panels on the
production line without collisions.
also stands up to hot glass panel temperatures associated with solar cell
manufacturing. Gingerich says the conveyors have a high-temperature
option that allows the belts to withstand temperatures up to 200C.
to the rigors of solar cell production include ESD protection and cleanliness
provisions – such as coated belts that don't need external lubrication. These
provison allow the TSsolar to meet ISO 14644-1 Class 6 cleanroom standards.
Solar cells aren't the only goods that need special handling. Semiconductors, flat panel displays, hard disk drives,
medical devices, photovoltaics and micro-electromechanical systems also need
conveyors that can protect them from ESD and contamination as well as gently
transport them – without collisions or sudden starts or stops.
For the cleanroom conveyors used in
these manufacturing processes, Bosch-Rexroth
has entered into a joint sales agreement with Switzerland's Middlesex
Industries SA, a specialist in
cleanroom-capable handling and logistics systems.
Here at the show, Middlesex showed off
a Series 8 Clean Drive conveyor. With a mechanical design that features
ESD-resistant and low-particulate polymers for the conveyor wheels, the Series
8 conveyors are capable of meeting Class 100 cleanroom standards – though the
company also offers models that meet more stringent standards. Adrian Pyke,
Middlesex's vice president of U.S. operations, called it a system for "cleanish
manufacturing" of products such as medical and electronic devices.
This conveyor system employs a unique
drive system in which a series of custom-wound stepper motors with magnetic
hysteresis clutches directly drive the conveyor's powered rollers. Photo
sensors and a Linux-based controller, which has been embedded into the conveyor
frame, round out the system.
Together, the drive, clutch sensors and
controls enable the system to asynchronously accumulate goods without
collisions or slippage on the belt. "The system creates a contactless buffer
between all the objects on the conveyor," says Pyke.