Chun H Li

7135792, Nov 14, 2006

May 11, 2005

11/127469

Thomas J. Devaney - Watchung NJ, US
Chun Li - Plainview NY, US

Dexter Magnetic Technologies, Inc. - Fremont CA

H02K 41/00

310 12

An embodiment of the invention is a particular arrangement of permanent magnets that generates a higher strength and more uniform magnetic field than existing permanent magnet arrangements for a voice coil motor. The permanent magnet arrangement of an embodiment is based on the Halbach arrangement of permanent magnets. The increased magnetic field strength and uniformity allows for a voice coil motor that is both capable of higher frequency actuations as well as more uniform force over the full stroke of the actuation.

8305177, Nov 6, 2012

Jan 5, 2010

12/652621

Chun Li - Plainview NY, US
David Choit - Dix Hills NY, US

Dexter Magnetic Technologies, Inc. - Elk Grove Village IL

H01F 7/02

335306

A magnet assembly for decoupling a plurality of different types of magnetically operated security devices includes a center pole magnet having a magnetic orientation along a first direction. A plurality of magnets adjacent to and surrounding the center pole magnet define an opening above the center pole magnet. Each adjacent magnet has a magnetic orientation orthogonal to the first direction. An end pole magnet is disposed adjacent to one of the magnets adjacent to the center pole magnet. The end pole magnet has magnetic orientation opposed to the first direction.

8520333, Aug 27, 2013

Apr 11, 2011

13/084012

Chun Li - Plainview NY, US

Dexter Magnetic Technologies, Inc. - Elk Grove Village IL

G11B 5/03
H01F 13/00

360 66, 361149

A structure for erasure of magnetic media in a hard drive includes a main field pole magnet polarized in a direction toward a drive spindle motor in the hard drive. At least two quadrature magnets are disposed adjacent the main field pole magnet and polarized in a direction toward the main field pole magnet. The main field pole magnet and the at least two quadrature magnets are shaped to provide a slot for insertion of the magnetic media. At least two inverse polarity magnets are disposed on portions of the main pole and quadrature magnets forming the slot. The inverse polarity magnets are polarized in a direction opposed to the direction of the main field pole magnet.

49804499, Dec 25, 1990

Jul 14, 1988

7/219290

Joachim B. Kohn - Highland Park NJ
Chun Li - Piscataway NJ

Rutgers, The State University - Piscataway NJ

C08G 7300
C08G 6540

528211

Novel polyiminocarbonates having molecular weights exceeding 70,000 daltons. Novel solution polymerization and interfacial polymerization processes for the preparation of polyiminocarbonates in which cyanate compounds are reacted with diphenol compounds in the presence of a strong base catalyst.

51400944, Aug 18, 1992

Jul 13, 1990

7/553224

Joachim B. Kohn - Highland Park NJ
Chun Li - Piscataway NJ

Rutgers, The State University - Piscataway NJ

C08G 7300
C08G 6540

528211

Novel polyiminocarbonates having molecular weights exceeding 70,000 daltons. Novel solution polymerization and interfacial polymerization processes for the preparation of polyiminocarbonates in which cyanate compounds are reacted with diphenol compounds in the presence of a strong base catalyst.

52645371, Nov 23, 1993

Mar 5, 1992

7/846603

Joachim B. Kohn - Highland Park NJ
Chun Li - Piscataway NJ

Rutgers, The State University - Piscataway NJ

C08G 7300

528211

Novel polyiminocarbonates having molecular weights exceeding 70,000 daltons. Novel solution polymerization and interfacial polymerization processes for the preparation of polyiminocarbonates in which cyanate compounds are reacted with diphenol compounds in the presence of a strong base catalyst.

52429970, Sep 7, 1993

Nov 19, 1992

7/978787

Joachim B. Kohn - Highland Park NJ
Chun Li - Piscataway NJ

Rutgers, The State University of New Jersey - New Brunswick NJ

C08G 6700

525534

Poly(N-phenyl urethanes) and methods of preparing same by heating poly(N-phenyl iminocarbonates) to a temperature above 250. degree. C. so that the backbone of the polyiminocarbonate rearranges to form the poly(N-phenyl urethane). Poly(N-substituted iminocarbonates and methods of preparing same by suspending a dialkaline diphenol in an aprotic solvent at a basic pH and adding to the suspension an N-substituted iminophosgene. Methods for making heat-stable articles by forming an article from a poly(N-phenyl iminocarbonate) while heating the article to a temperature above about 250. degree. C. so that the poly(N-phenyl iminocarbonate) rearranges to form a poly(N-phenyl urethane).