“Flat” linear motor with steel-core forcer provides highest power in low-profile design

Citation

(2006), "“Flat” linear motor with steel-core forcer provides highest power in low-profile design", Assembly Automation, Vol. 26 No. 1. https://doi.org/10.1108/aa.2006.03326aaf.003

“Flat” linear motor with steel-core forcer provides highest power in low-profile design

“Flat” linear motor with steel-core forcer provides highest power in low-profile design

Keywords: Linear motion

The BLMFS5 “Flat” linear motor range from Aerotech has a special laminated iron-core design which yields more force per coil-length than equivalent sized motors by efficiently focussing the magnetic field created by the winding. A typical dynamics improvement of up to 25 per cent compared to other manufacturers' equivalent sized motors has been achieved thanks to the proprietary process Aerotech have developed using design and manufacturing experience of “Flat” and “U-channel” linear motors over the past 15 years (Plate 3).

Plate 3 The BLMFS5 “Flat” linear motor range from Aerotech

In comparative tests with competitive linear motors of the same envelope size, the Aerotech motor delivered higher dynamics for a given temperature rise and conversely had a lower temperature rise for same dynamics. (Test results are available on request from Aerotech web site: www.aerotech.co.uk) This shows that the Aerotech motor performed more efficiently than its rivals and in applications where existing linear motors are running too hot or not providing enough power, the BLMFS5 will simply outperform them.

Furthermore, the range is available with optional water cooling for even higher performance applications where minimal motor size is essential. The range combines a rare-earth magnet system and a low-profile package for a peak force rating of up to 1,500N which is practically specified with and without water cooling for a continuous force rating of almost 700N at an operating temperature of 125°C.

Aimed at high-speed, point-to-point precision motion application solutions for pick and place systems, automated assembly and general automation, the compact and competitively priced BLMFS5 has a nominal width of just 66mm and a combined forcer and magnetic track height of just under 37 mm. Travel range is effectively unlimited by stacking magnet tracks; available in 240 and 420 mm lengths or customised for special applications. Mechanical interfacing is simplified via a matrix of M5 mounting holes on the forcer and M4 clearance holes on the magnet track.

The ceramic/epoxy moving forcer assembly contains hall-effect devices for motor commutation and a thermistor-based temperature sensor to help ensure safe operation when used in demanding applications. One metre long flying-lead cable assemblies are provided for convenient and quick electrical connection for motor, HED's and thermistor. A wide range of Aerotech brushless servo amplifiers are available to drive the BLMFS5 according to the customers' force and speed requirements. Motion control is available from single axis configuration using the Soloist Intelligent Drive to applications of up to 32 axes of decentralised motion, using Aerotech's “soft-motion” A3200 Automation Platform with high speed IEEE-1394 Firewire^® network and dedicated modules for HMI, PLC and Vision.

Customisation options for the BLMFS5 include higher power magnets to further increase force output, special mechanical interfacing and electrical connectors for simplified installation. One of the main advantages of applying linear motor direct-drive technology is the elimination of backlash, hysterysis and windup as well as the wear and maintenance issues associated with traditional power transmission systems such as ball screws, belt drives and rack and pinion based motion control and positioning systems. The attractive magnetic force generated by the motor has also been used to apply pre-load to linear bearing systems and being non-contact components, their suitability for clean- room and contamination restricted applications such as medical devices is assured.

Aerotech also manufactures a wide range of “U-channel” brushless linear servo motors, used extensively in its own programme of linear stage and gantry systems with cross-roller, linear motion guide and air bearing technologies. The quality of this “tried and tested” application experience continues to drive the research and development programme towards higher performance and competitively priced direct-drive motors. The range is also used in component form in robotics, specialised actuators, fibre optics and photonics alignment, assembly machines, machine tools, semiconductor equipment, electronic manufacturing, vision systems, and in many other demanding industrial automation applications.