MAGNET TARGET WHEELS
Phoenix America Inc.’s radial, multi-pole magnetized target wheels are uniquely constructed of a proprietary mix of magnet materials and engineering thermoplastics. The result is a unitized magnet target wheel which produces a very accurate, homogeneous magnetic field and has very tight mechanical tolerances. This provides for a very low cost product, compared to the traditional, high component count wheels with individual magnet bars glued into place.
Radial, multi-pole target magnets are available with a large range of pole patterns on 5/8”, 1”, 2”and 3-5/8” outside diameters. The North and South pole spacing accuracy is better than .25 degrees. All standard radial target magnet wheels are magnetized with the pole pattern on the outside diameter with alternating North and South poles.
Tight tolerance control, precise pole location, and very consistent magnetic performance make these target wheels well suited for speed, commutation, encoding, counting and tachometry applications. Three standard grades of materials allow for a wide range of air gap capabilities. Adhesive bonding is the recommended mode of mounting, although many customers have satisfactorily attached these targets to their shafts using various other schemes. Please feel free to contact Phoenix America Inc. for application engineering or product assistance.
PROXIMITY MAGNET TARGETS
Phoenix America Inc. proximity target magnets are manufactured from a proprietary compound that utilizes the advantages of high energy Neodymium-Iron-Boron material. The Proximity target magnets are designed for use in either a slide-by or head-on mode. All standard target magnets are magnetized axially, with the one pole on each the end of the magnet. A listing of popular target magnets appears on the following pages, grouped by mode of use. Many other target magnets are available, however they are not necessarily stocked. Please do not hesitate to ask us about other sizes and shapes that may be more suitable for your application.
The head-on mode of operation is simple, works well, and is relatively insensitive to lateral movement (offset). The user should be aware that overtravel of the mechanism could cause damage to the sensor and magnet target. The attached charts indicate operate and release positions for three magnet targets. Note that for the head-on mode, the airgap is in the direction of travel. Alternate magnet targets can be used to optimize the performance of the sensor for a given application. Also the addition of ferrous materials can be used to change the performance of any magnet target.
Moving the magnet target to the side as depicted produces the slide-by mode of operation. The slide-by mode is commonly used to avoid direct contact of the sensor and magnet target if overtravel of the mechanism is likely. The attached charts indicate operate and release positions for three magnet targets. Note that for the slide-by mode, the air gap is constant and the offset is in the direction of travel. Alternate magnet targets can be used to optimize the performance of the sensor for a given application. Also the addition of ferrous materials can be used to change the performance of any magnet target.