A motor the size of a pencil tip!

Citation

(2003), "A motor the size of a pencil tip!", Industrial Robot, Vol. 30 No. 3. https://doi.org/10.1108/ir.2003.04930cad.003

A motor the size of a pencil tip!

A motor the size of a pencil tip!

Keywords: Motors, Actuators, Miniaturisation

The maxon RE 8 has been designed for applications which require a powerful motor unit to be packed into a very tight space – in situations where there can be no compromise on precision and reliability (Plate 3).

Only 8 mm in diameter, 16 mm long and weighing less than 4 g, it is nevertheless capable of achieving an impressive nominal power rating of 0.5 W.

Plate 3 The maxon RE 8 has been designed for applications which require a powerful motor unit to be packed into a very tight space – in situations where there can be no compromise on precision and reliability

Its ceramic shaft is as thin as a pencil lead – just 0.8 mm in diameter – and turns in two sleeve bearings. The superiority of the ceramic material over steel in terms of its electrical insulating properties allows for a very compact commutator design. Bearing wear is also minimal in comparison with that of systems using steel components.

High speed and virtually everlasting life are guaranteed, thanks largely to the precious metal brushes, which ensure constant and low-contact resistance between themselves and the commutator – even after a prolonged standstill.

The "heart" of the motor is the worldwide patented ironless rotor, System maxon^®, which benefits from maxon's unique coil winding. Advantages of its lightweight construction include an unusually low mass inertia and very fast acceleration. There is no magnetic detent at all – and minimal electromagnetic interference.

Combined with a neodymium permanent magnet – one of the best magnetic materials currently available – the ironless winding makes the design of these maxon motors much more efficient than those of their competitors.

To add to its versatility, the RE 8 is compatible with maxon planetary gearheads – which can be attached for applications where the given motor speed is too high and the torque is too low. It can also be fitted with an encoder system, if needed, although its integral Hall effect sensors will be sufficient for most speed and position detecting purposes.

"Among other uses, the characteristics of the maxon RE 8 make it perfect for 'light chopping' in a wide variety of laser-based equipment," says Keith Ellenden, CEO of maxon motor uk.

"With its small size and weight, minimal current requirement and exceptional reliability, it is also ideally suited to life-preserving medical applications such as body-worn insulin pumps."

For further information, contact: maxon motor uk ltd, Maxon House, Hogwood Lane, Finchampstead, Berks, RG40 4QW. Tel: 01189 733337; Fax: 01189 737472; E-mail: sales@maxonmotor.co.uk. Further technical details are also available from the maxon Web site: www.maxonmotor.co.uk