Sensorless Position Measurement
System for Control of an Electromagnetic Actuator U.S. 6,249,418 Gary Bergstrom
We control pulse duty cycle, sense current, and derive the position and velocity of the actuator, as needed for sensorless servo feedback and soft landing control.
State Space Controller
State space control of solenoids U.S. 7,099,136 Joseph Seale, Gary Bergstrom
multiple simulation runs or multiple instrumented landings we derive a
“roadmap,” in the solenoid state space, of routes that lead to good
landings. Use of this “roadmap” yields
consistent good results with straightforward software.
Single-Winding Dual-Latching Valve Actuation Solenoid U.S. 6,724,606 Joseph Seale, Gary Bergstrom
two windings of a traditional system are wired in series and driven
from one channel
of driver electronics. The surprise:
one driver is almost as efficient as from two, and significantly
Three Wire Drive/Sense for Dual Solenoid, U.S. 7,612,978 Gary Bergstrom, Joseph Seale
The two windings of a traditional system are wired in series and a center tap brought out from the common connection, so the windings are driven with three power drivers instead of four.
Flat Lamination Solenoid U.S. 6,550,745 Gary Bergstrom
Stack the armature laminations in a horizontal plane rather than in a vertical plane. The eddy current losses are only slightly worse, and the structure is mechanically much stronger.
Side-by-Side Helical Spring
Spring for Valve Control in Engines U.S. 6,341,767 Joseph Seale, Gary Bergstrom
A single piece of spring wire is bent into a double side-by-side helix with fixed ends and a moving center attachment. It’s a good shape to fit the available space of a valve actuator, it’s less expensive, and the moving mass is lower.
Quick Landing Solenoid
A Solenoid for Efficient Pull-In and Quick Landing, U.S. 6,737,946 Joseph Seale, Gary Bergstrom
Passive magnetic design gives a quick transition from armature deceleration to latching and holding, reducing total transit time. Passive damping windings complement active servo control to yield landings that combine quickness with low impact.
Sensorless Position without Drift
System to Determine Solenoid Position and Flux without Drift U.S. 6,300,733 Gary Bergstrom
Our “Sensorless Position Measurement” is modified to overcome long-term drift of the flux linkage integral, using current ripple data associated with the frequency of the PWM drive voltage.
Magnesense LLC Gorham,ME (207) 839-8637
©2005-2007 Joseph Seale