Magnetic innovations
> Magnetic error compensation for the highest precision
Together with the considerable cost advantages, the flexibility of Bogen's patented manufacturing technology, the general advantages of magnetic standards such as robustness under harsh process conditions and the large distance tolerance are the key factors for the success of Bogen's products.
Nonetheless, optical and inductive procedures for precision applications for large shafts are still dominant, even though elaborate mechanical bearings are often necessary and mounting tolerances are often very limited.On the other hand, magnetic rotary sensors are utilised in large quantities in numerous standard industrial applications to determine the rotation speed, position, and angle.
For cost reasons, these rotary sensors are usually magnetised through procedures that utilise set pole lengths. The disadvantages of these procedures are considerable. Eccentricity errors and visible magnetic junctions considerably limit the precision of this procedure to ±1°.
New demanding customer utilisations are making it increasingly necessary to measure more precisely and at higher resolutions.
In order to be able to supply innovative solutions for these applications, the engineers at Bogen have developed a new procedure for automated error compensation.
The new developments are furthering the advantages of the dynamic Bogen magnetisation principle with real angle graduation.
For the Bogen procedures, junctions and eccentricities have principally not played a role so far, as the actual pole widths have been flexibly fitted to the diameter of the rotary sensors through a high-resolution angle measuring system. The interesting thing about the new technology is that unique ring errors of the magnetic materials, such as inhomogeneity or fluctuations of the layer thickness, can be well compensated.
The new procedure is as simple as it is ingenious. When the target value is off, the pole position is altered until the individual optimum status of each rotary sensor has been achieved.
Whether simple mechanical magnetic rings are to be utilised for a low-cost solution or precise mechanical rotary sensors are required for high-precision applications, the new procedure of error compensation increases the graduation precision by a factor of 5-10.
This makes completely new fields of application for magnetic measuring systems possible.
...Error compensation
> NEW magnetisation devise for large diameters
In order to be able to optimally utilise the procedure for error compensation for applications with large diameters, the existing production facilities were expanded with a state-of-the-art magnetisation devise, which is designed for ring diameters of up to 1,200 mm and which can provide separation precision of under 10".
