Among changes from the 2002 survey on proximity sensors, 2005 results show significant gains in the other category, which indicate other bus technologies entering the arena. |
When asked about the mix of applications, Ernie Maddox, product manger, position sensors at ifm efector inc. (www.ifmefector.com), says he believes th
em to be accurate. ‘Applications for proximity sensors in continuous or batch processes are limited. In discrete manufacturing, proximity sensors are used for both detecting machine position and detecting products being manufactured. Use of proximity sensors for detecting machine position has grown dramatically over the past 15 years. The primary reason for this trend has been the switch from mechanical switches and relay logic to the use proximity sensors and PLCs by machine builders. This trend has now run its course for the most part.’
In the product detection arena, applications include part presence in fixtures, part counting on conveyors, and ‘line full/line empty’ detection on conveyor lines and machine infeeds. According to Maddox, the trend is growing ‘as manufacturers continue to implement sensors to improve production rates and to improve the quality of parts being manufactured. Error proofing and part verification are major trends today.’
Rough, tough, rugged
Corrosive environments, moisture, and collisions (and even near misses) with sharp, heavy, oily, or abrasive parts can be rough on proximity devices. Serdar Guvenc, product manager at Sick Inc. (www.sick.com) points to ruggedness as an essential design characteristic that is growing even more significant. ‘Sick sees both price and ruggedness as very important,’ says Guvenc. ‘While standard inductive sensor pricing is declining due to standardized manufacturing techniques,’ he continues, ‘many manufacturers in