Magnetic disk couplings cope with angular or parallel misalignment

Paul Boughton
A new series of magnetic disk couplings from Sterling Instrument features no friction or wearing parts, uses no electricity and has no magnetic particles to leak. These units, identified as the S50DCM... (inch) and S50DCMM... (metric) series, are stocked in eight different bore sizes ranging from 0.1875 to 1.000inch (5mm to19mm). The couplings consist of two opposing disk halves with powerful rare earth magnets. The torque applied to one disk is transferred across an air gap to the other disk. Because of the simple flat design, one can have angular misalignment of up to 3 degrees or parallel misalignment of up to 1/4inch (6.4mm) and still transmit almost full torque.
These 416 stainless steel couplings incorporate an NdFeB, nickel plated magnet. The hub sections are offered singularly and with or without a keyway. The coupling outside diameter ranges from 1.72 to 2.86inches (43.7 to 73mm).
Other features include high-accuracy, repeatable torque control, and easy-to-adjust, easy-to-apply, smooth torque transfer with no friction, since there is no physical contact between the driving and driven parts.
Applications include: material handling such as for conveyor belts; film transport; capping of syringes or bottles; shrink wrapping; constant-tension coil winding; and film tensioning. 3D CAD models are available via the website.
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