Medical and laboratory devices that require compact, powerful motors are using PMW’s brushed pancake motors in crucial applications. Printed armature motors are ideal for applications such as these, since their design offers inherently high torque, rapid acceleration and deceleration, zero cogging and they are easy to control.
Their slim packaging means that smaller motors can fit neatly into printers, centrifuges and sample preparation devices, while larger motors can rotate MRI and x-ray equipment for example. Others are used in material testing machines, milk analysers and floor polishing machines.
Application: an MRI scanner
An MRI scanner is using PMW’s GPM16 motor to turn its scanning drum for positioning and rotating around the patient. This brushed pancake motor has zero cogging to ensure extremely smooth turning of the drum, since a motor with any cogging or torque ripple would have this jerkiness amplified through the drivetrain. Needless to say, the motors work perfectly in the high magnetic fields generated by the MRI scanner.
Application: a mobile x-ray machine
A higher powered GPN16 motor is used in the drivetrain to move a heavy mobile x-ray machine from patient to patient. The motor uses an array of rare earth NdFeB (neodymium) magnets for higher torque output, almost double that possible from ferrite magnets, to support and move the machine.
PMW worked with the load information supplied by the client (such as that arising from the slopes and bumps in the hospital floor) to customise the printed armature motor with a fully bespoke mounting plate in 10 mm thick steel and a reinforced bearing housing. The motor is mounted with the shaft horizontal, connected to each drive wheel via a gear train. The front motor plate and bearing housing enables the motor to support the whole weight of the x-ray machine. Being flat, it does not encroach on the load space, thereby keeping the machine as compact as possible.