Customised precision "˜slit' packages used at ISIS facility

Heason Technology has designed and manufactured a range of application customised and completely non-magnetic four-axis precision "slit" packages for use on the LARMOR instrument at the STFC's ISIS neutron and muon beamline facility in Oxfordshire. LARMOR is presently under construction and due for completion in 2014. Following Heason's success in supplying similar neutron beam conditioning positioners for the WISH and NIMROD instruments at ISIS, as well as many other micropositioning devices for a number of synchrotron source/particle accelerator applications worldwide, the West Sussex-based motion systems specialist has supplied several types of slit packages for use in ambient and UHV environments that suit the wide range of diffraction and spectroscopy techniques that the new multi-purpose instrument will offer the scientific community.

The detailed nature of the project, involving a rigorous design, development and manufacturing process with ISIS scientists and engineers, demonstrates Heason Technology's capability to provide bespoke motion systems to its customers across research and industry.

Heason's slit packages, which all feature piezo-ceramic direct drive linear motor systems and ceramic bearings, are essentially four-axis motorised linear blades that are precisely positioned to sub-micron levels in order to modify the face area and size of the neutron beam, to enable the scientists to tune its resolution and divergence in order to achieve the optimal frequency required for the materials being examined on the instrument.

A design feature engineered by Heason's expert design team was the development of the package comprising of ceramic motors and bearings, support frames, housings and feedback encoders assemblies built using completely non-ferromagnetic materials so as not to influence the instrument's measurement capability in any way. With no lead-screws or externally mounted motors, the zero backlash direct drive design has reduced the amount of components typically employed in slit packages that use rotary motors - which also require complex magnetic screening and feed through devices - resulting in increased long-term reliability, greater stability, much improved accuracy and positional repeatability, as well as considerable space savings.

Non-magnetic micropositioning element

The ceramic motor technology used in the packages - from Nanomotion, an exclusive distribution partner of Heason Technology - not only provides the non-magnetic micropositioning element for the application but also benefits from its ability to hold position with no movement whatsoever when power is removed. This feature allows the slit package to be isolated from power at the critical measurement phase, maintaining its exact dimensions but eliminating any potential for movement and heating that could influence the measured results.

Heason Technology has developed many customised jaw/slit package variants for the global community of synchrotron research facilities. From its UK design, manufacturing and assembly facility, the Company plans to add to the range and invites suggestions from interested parties to develop standard jaw/slit packages with a fixed range of apertures, and with standard drive and feedback options.

For further information about standard and custom motion system design and build, go to the website at www.heason.com