H01F 7/18
Circuit arrangements for obtaining desired operating characteristics
Official title: Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
H01F7/18 (Circuit arrangements for obtaining desired operating characteristics) appears on 993 US grants and 800 published applications in this corpus.
Search patents in H01F- Granted patents
- 993
- Published applications
- 800
- Assignees
- 575
- Inventors
- 2,177
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 9 | 0 |
| 1977 | 5 | 0 |
| 1978 | 6 | 0 |
| 1979 | 4 | 0 |
| 1980 | 6 | 0 |
| 1981 | 13 | 0 |
| 1982 | 14 | 0 |
| 1983 | 7 | 0 |
| 1984 | 10 | 0 |
| 1985 | 6 | 0 |
| 1986 | 9 | 0 |
| 1987 | 20 | 0 |
| 1988 | 6 | 0 |
| 1989 | 8 | 0 |
| 1990 | 10 | 0 |
| 1991 | 7 | 0 |
| 1992 | 8 | 0 |
| 1993 | 8 | 0 |
| 1994 | 11 | 0 |
| 1995 | 17 | 0 |
| 1996 | 16 | 0 |
| 1997 | 16 | 0 |
| 1998 | 31 | 0 |
| 1999 | 30 | 0 |
| 2000 | 25 | 0 |
| 2001 | 21 | 3 |
| 2002 | 21 | 17 |
| 2003 | 18 | 14 |
| 2004 | 14 | 23 |
| 2005 | 16 | 29 |
| 2006 | 18 | 23 |
| 2007 | 13 | 30 |
| 2008 | 19 | 33 |
| 2009 | 18 | 44 |
| 2010 | 26 | 29 |
| 2011 | 23 | 21 |
| 2012 | 21 | 24 |
| 2013 | 24 | 35 |
| 2014 | 18 | 16 |
| 2015 | 29 | 41 |
| 2016 | 25 | 28 |
| 2017 | 27 | 45 |
| 2018 | 29 | 49 |
| 2019 | 55 | 47 |
| 2020 | 47 | 51 |
| 2021 | 43 | 50 |
| 2022 | 43 | 48 |
| 2023 | 39 | 31 |
| 2024 | 41 | 30 |
| 2025 | 29 | 19 |
| 2026 | 14 | 20 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
- H01F 7/1844Monitoring or fail-safe circuits518
- H01F 7/1805Circuit arrangements for holding the operation of electromagnets or for holding the276
- H01F 2007/1888Using pulse width modulationIndexing code102
- H01F 7/1877Controlling a plurality of loads54
- H01F 2007/1894Minimizing impact energy on closure of magnetic circuitIndexing code44
- H01F 7/1872Bistable or bidirectional current devices33
- H01F 7/1883By steepening leading and trailing edges of magnetisation pulse33
Recent patents
- Switch arrangement and method for operating a switch arrangement25 Aug 2026US 12,718,999 B2Siemens Aktiengesellschaft
- Dialysis system having reduced valve noise18 Aug 2026US 12,712,080 B2Vantive Health GmbH
- Metamaterial and metadamper7 Jul 2026US 12,676,257 B2The Royal Institution for the Advancement of Learning/Mcgill University
- Dialysis system having a valve functionality assessment16 Jun 2026US 12,658,323 B2Vantive Health GmbH
- Solenoid position sensing16 Jun 2026US 12,658,348 B2Rivian IP Holdings, LLC
- Method and system for enhancing subsurface permeability via electromagnetic fields and electromagnetically responsive particles27 Aug 2026US 2026/0251044 A1
- Solenoid actuator efficiency optimization13 Aug 2026US 2026/0237547 A1Analog Devices International Unlimited Company
- Circuit and method for driving an inductive load with reduced power loss13 Aug 2026US 2026/0237548 A1
- Electromagnet current control method and related assembly6 Aug 2026US 2026/0229393 A1Crrc Qingdao Sifang Co., Ltd.
- Demagnetization of working-channel tools in an electromagnetically tracked endoscope30 Jul 2026US 2026/0221326 A1Magnisity Ltd.
Most cited
By later US patents
- Method and apparatus for rapidly changing a magnetic field produced by electromagnets164US 6,128,174 AStereotaxis, Inc. · 2000
- Method of operating an electromagnetically actuated fuel intake or exhaust valve of an internal combustion engine102US 4,823,825 A1989
- Electromagnetic contactor with energy balanced closing system101US 4,893,102 AWestinghouse Electric Corp. · 1990
- Methods and applications for efficient genetic suppressor elements101US 5,217,889 A1993
- Monitor and control circuit for electric surface controlled subsurface valve system91US 5,293,551 AOtis Engineering Corporation · 1994