Thomson delivers smooth, backlash-free “horsepower”

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Thomson ball screw and linear rail bearing assemblies support heavy loads while delivering accurate equine patient positioning for fast and accurate CT scans.

The EquusCT from Artec Imaging is a patient position and CT scanning table with floating carousel that offers a high degree of manoeuvrability for veterinarians practising equine healthcare. EquusCT utilises a Thomson ball screw assembly and Thomson bearings and shafting rail assemblies to enable a horse’s head, neck, front and rear legs to be accurately scanned in any CT scanner, with 2D and 3D diagnostic image output.

Art Gaines, President, Artec Imaging, says: “In selecting components for the EquusCT, smooth, backlash-free motion, as well as total weight and drive accuracy, were paramount considerations. The Thomson solution met all of our design criteria, including the need for highly accurate and repeatable motion, and it did so within budget.”

Thomson’s ball screw assembly moves the EquusCT carousel in a longitudinal direction for a distance of 36 inches. The ball screw is driven by a servo motor that gets its data from an on-board computer; the computer obtains its data from a sensor that tracks the movement of the CT table-top.

The longitudinal movement and weight of the carousel/carriage/patient is accomplished by riding on two 1-inch Thomson 60 Case LinearRace stainless steel shafts that are each 84 inches long, with double pillow block bearings. The lateral movement and combined weight of the carousel/carriage/patient is accomplished by riding on four 0.75-inch 60 Case shafts, each 15 inches long and supported by double pillow blocks. The Thomson equipment supports total loads up to 1360kg (3000 lbs.) while delivering lateral movement accuracy to +/- 3.0 inches – capabilities that permit ease of patient positioning and accurate anatomical scans for horses and other large animals up to 935kg (2100 lbs.).

Gaines explains: “The EquusCT is positioned directly over a CT couch for scanning head, neck or limbs without any electrical or mechanical interfacing. It automatically tracks with the CT couch, moving the selected anatomy into the gantry for scanning. The EquusCT can be customised to suit any fixed or variable height CT/TOMO scanner. The head, rump, leg supports and IV pole support are secured to the carousel and can be placed around the outer perimeter for optimum patient positioning.”

The EquusCT imaging table is used currently in private equine clinics around the world. It is also used in schools of veterinary medicine at the University of Florida, Oregon State University, North Carolina State University, Louisiana State University, Texas A & M University, University of Tennessee, Auburn University, the University of Queensland in Brisbane, Australia, Murdoch University, Perth Australia, the University of Melbourne, Melbourne, Australia, and Charles Sturt University, Wagga Wagga, Australia.

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