US 11,901,142 B2
Variable field magnetic couplers and methods for engaging a ferromagnetic workpiece
David H. Morton, Boulder, CO (US); Cengiz Kizilkan, Ingolstadt (DE); and Paul J. Karp, Boulder, CO (US)
Assigned to Magswitch Technology, Inc., Superior, CO (US)
Filed by David H. Morton, Boulder, CO (US); Cengiz Kizilkan, Ingolstadt (DE); and Paul J. Karp, Boulder, CO (US)
Filed on Dec. 19, 2022, as Appl. No. 18/084,194.
Application 18/084,194 is a continuation of application No. 17/130,868, filed on Dec. 22, 2020.
Application 17/130,868 is a continuation of application No. 15/965,582, filed on Apr. 27, 2018, granted, now 10,903,030, issued on Jan. 26, 2021.
Claims priority of provisional application 62/634,783, filed on Feb. 23, 2018.
Claims priority of provisional application 62/490,705, filed on Apr. 27, 2017.
Prior Publication US 2023/0343530 A1, Oct. 26, 2023
Int. Cl. H01H 36/00 (2006.01); H01F 7/02 (2006.01); H01F 7/04 (2006.01); B65H 3/16 (2006.01); B66C 1/04 (2006.01)
CPC H01H 36/002 (2013.01) [B65H 3/16 (2013.01); B66C 1/04 (2013.01); H01F 7/021 (2013.01); H01F 7/0226 (2013.01); H01F 7/0242 (2013.01); H01F 7/0257 (2013.01); H01F 7/04 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A fixture for holding a ferromagnetic workpiece, the fixture comprising:
a frame;
at least one magnetic coupling device supported by the frame and positioned to support a lower side of the ferromagnetic workpiece, each magnetic coupling device comprising:
a housing having a first side;
a plurality of workpiece contact interfaces supported by the housing and adapted to contact the ferromagnetic workpiece;
a first permanent magnet supported by the housing and having an active N-S pole pair;
a second permanent magnet supported by the housing and having an active N-S pole pair, the second permanent magnet being moveable relative to the first permanent magnet;
an actuator operatively coupled to the second permanent magnet to move the second permanent magnet relative to the first permanent magnet; and
an electronic controller operatively coupled to the actuator, the electronic controller including logic which actuates the actuator to position the second permanent magnet relative to the first permanent magnet in at least each of:
(a) a first state wherein the second permanent magnet has a first position relative to the first permanent magnet to provide a first level of magnetic flux available to the ferromagnetic workpiece at the workpiece contact interfaces, the first level of magnetic flux available to the ferromagnetic workpiece at the workpiece contact interfaces being insufficient to hold the ferromagnetic workpiece relative to the magnetic coupling device; and
(b) a second state wherein the second permanent magnet has a second position relative to the first permanent magnet to provide a second level of magnetic flux available to the ferromagnetic workpiece at the workpiece contact interfaces, the second level of magnetic flux available to the ferromagnetic workpiece at the workpiece contact interfaces being sufficient to hold the ferromagnetic workpiece relative to the magnetic coupling device, the second level of magnetic flux being greater than the first level of magnetic flux.