Low-Inertia Motors Move Forward Biomedical Imaging Technology

OriginallyPublished MPMN January 2004

HOTLINE

Low-Inertia Motors Move Forward Biomedical Imaging Technology

Rapid 1-mm x-y movements are accurateto within 1 µm

Rita Emmanouilidou

Traditional instruments for positioning slides, test tubes, and microarrays have depended on leadscrew mechanisms. However, such devices are subject to friction and rotational inertia, which makes it difficult to meet OEM demands for high throughput. Low-inertia, direct-drive Micro Linear motors are a better alternative for precise, repetitive, short-distance positioning applications, according toCopley Controls (Canton, MA). The company's motors currently are 
used in blood cell- imaging devices.

The motors' tubular polymer construction is designed with a 0.016-in. symmetrical air gap between the fixed and moving parts. This helps to lessen friction and wear. The units are available with a peak force from 19 to 45 N and continuous force from 3.1 to 8.7 N; they achieve a 15-25-m/sec2 peak acceleration range and 3-m/sec velocity. The thrust rods, which measure 11 mm in diameter, can be specified in 62-510-mm lengths. Forcers that encapsulate the drive coils are available in lengths of 36-113 mm. They measure 34 mm wide and 25 mm in height. 

In the blood cell-imaging device, two Micro linear motors form an x and y stage that positions blood-coated slides under a camera lens. The equipment captures images of white blood cells that measure 10-25 µm in diameter. Positioning accuracy in this application is 1 µm. As many as 200 blood cell images can be captured froma few square centimeters of slide surface. The motors complete repetitive 1-mmx-y movements at1-µm accuracy within 25 milliseconds.

Copley Controls
20 Dan Rd.
Canton, MA 02021
tel: 781/828-8090
fax: 781/828-6547
www.copleycontrols.com 

Copyright ©2004 Medical Product Manufacturing News