Magnetizing Fixtures

The magnetizing fixture - i.e. that part of the system in which the magnetic fields are generated - is always specially designed in accordance with the customers’ demands.

At best, we only have to recalculate the dimensions for an axial coil, and the fixture can be constructed and manufactured pursuant to a standard method. In more complicated cases, it requires complex FEM calculations taking into account loss of eddy currents together with multipolar magnet structures.

We regularly validate the field characteristics and strengths by means of FEM calculations before construction and often already during the quotation stage. Through this, we save our customers from unpleasant surprises - just with nontrivial and individual constructions. And, what is more, we can quarantee the magnetic result when we accept the order.

In all cases, the magnetic field is technically generated by a fast pulse current. The used currents are in the dimension between 1 kA and 70 kA. The pulse duration lies between 50 µsec and 250 msec (depending on the application).
A major problem as regards cycle time and lifetime of magnetizing fixtures is the warming up because of the required high energies. In principle, MAGSYS magnetizing fixtures are always air cooled. The required air volume is generated by a side-channel blower.

Here are some examples from earlier projects:

Fixture for Voice Coil Motors (VCM) in Hard Disks

With these fixtures we magnetize positioning systems in hard disk drives. This is a bipolar magnetization of NdFeB magnets. Their distinctiveness lies in the very small pole gap between the two poles. Reached cycle times are at approximately 1.7 sec per each magnet system. All systems of this kind operate in clean rooms. The magnet systems are used in disk drives by well-known producers such as Maxtor, Seagate oder Western-Digital.

Fixture for Multipolar Permanent Magnet Motors

Fixture for Multipolar Permanent Magnet Motors.

Fixture for the Magnetization of Loudspeaker Systems

Loudspeaker systems are magnetized either inside an axial fixture or, as shown in this picture, in the stray field of a flat coil arrangement.

Fixture for Multipolar Front Magnetization of Automotive Sensors

The magnetizing fields for high-polar magnetic applications are generated by complex and at the same time very precise conductor types.

Fixture for Magnetization of Position Sensors in Automotive Applications

In this application we magnetize four systems of a position sensor simutaneously. Through a special construction, the carriers are shielded against parasitic magnetization. The magnetizing fixtures are integrated in the automized line. The cycle time lies at approx. 5 sec per part. MAGSYS designed and provided the entire handling system as well.