Rotary actuator achieves high speeds
Sharon Tecklenburg, Marketing Executive, Ledex Products,
Lucas Control Systems Products, Vandalia, OH
Any motion-control system includes the following standard components: a load to be moved or influenced, a prime mover or output element, a position sensor, system controller, and signal conditioner, and some means of communication. Lucas Control Systems Products and the LedexActuation Product Group supply more than the conventional prime mover.
The InterAct is a bi-directional rotary actuator with internal PWM drive circuitry and an optical encoder for position sensing. It provides 100 oz-inches of torque over a total stroke of 45 degrees. The stroke takes place equally around the center zero-point for a ±22.5-degree stroke. Designed for higher-speed rotary-actuation devices, the actuator therefore achieves speeds exceeding 100 Hz with open-loop bandwidth of 78 Hz at -3db. Response time of 8 milliseconds to 20 degrees of rotation from rest is typical for low-mass loads.
Speed, precision, cool operation, and electromagnetic compatibility (EMC) of the actuation system require careful design of efficient drive circuitry. Ledex Products therefore incorporates pulse-width modulation (PWM) circuitry within the package of the InterAct. PWM provides a drive methodology to the actuator to vary the level of excitation applied to the coil.
To speak with a Lucas Control Systems Products applications engineer, call (800) 998-2298.
Modular gearmotors reduce cost
Christopher Cook, Joint Chief Executive,
David Brown Group PLC, Hudderfield, UK
Compatibility is critical when selecting geared motor ranges. Before David Brown designed the Series M, C, and F gear motors, engineers asked customers what they wanted. Many innovative features, such as a modular design, dimensional interchangeability, and a motor adapter system were developed to meet customer requirements.
The ability to fit any standard electric motor is a key feature of the new series of products. Thanks to the patented Radicon-Ector adapter system, all ranges accept all variants of standard IEC and standard NEMA flange-mounted electric motors without expensive modifications or interface connectors. This flexibility means that the original motor, and any replacements, may be sourced at very competitive prices from a wide range of suppliers.
Users can also fit standard motors in all variant types--such as ac, dc, single-phase, energy-efficient, washdown, and explosion-proof--without the high costs associated with gearboxes designed to accept special motor flange and shaft interfaces. Units are available in foot, flange, and shaft-mounted configurations in horizontal and vertical mountings.
All units in the family of products were developed with the aim of reducing manufacturing and repair costs, and maximizing product availability. The Radicon modular systems are based on a "kit" principle. David Brown produces sub-assemblies and packs and stores them individually.
A 90% reduction in inventory cost can be achieved by stocking spare parts in kit form; this allows instant replacement and reduces expensive down-time.
To speak with a David Brown applications engineer, fax 011 44 1484 420291.