A compressor design from Purdue University innovators proposes a new drive mechanism for compressors used in residential homes, supermarkets, other large buildings, trains, cars and refrigerated trucks.

Based in Indiana, the university researchers created a new design to create the orbiting motion for scroll compressors, which are commonly used in cooling systems of different sizes. 

The new design relies on a gear mechanism to create the orbiting motion of a scroll wrap within another stationary scroll wrap to compress a refrigerant. 

“In the conventional scroll compressor setup, typically an Oldham coupling is used, which is based on a metal to metal sliding contact,” said Leon Brendel, a Ph.D Student in Mechanical Engineering.

“This causes frictional losses and requires complicated wear-in processes for the manufacturer.”

“Our design is driven by a gear mechanism instead, aiming to reduce the overall friction to offer a more efficient compressor and simplify wear-in processes to reduce manufacturing cost.”

The Purdue orbiting scroll design is driven by a gear mechanism consisting of a centre gear and three smaller gears surrounding and connected to the centre gear. The smaller gears have off-centred anchor points to attach the base plate of the orbiting scroll.

“The mechanism also can be designed to define the orbit more accurately, thereby reducing leakage gaps, which could improve the compressor efficiency,” Brendel continued.

The Purdue design moves any weight-balancing away from the centre shaft to the three smaller gears, leading to a reduction of vibrations and potentially an increased maximum compressor speed.

Brendel said the Purdue compressor design has applications for cooling systems in residential homes, supermarkets and other large buildings, trains, cars and refrigerated trucks.