H02K 31/02
Acyclic motors or generators, i.e. dc machines having drum or disc armatures
Official title: with solid-contact collectors
H02K31/02 (Acyclic motors or generators, i.e. dc machines having drum or disc armatures) appears on 68 US grants and 55 published applications in this corpus.
Search patents in H02K- Granted patents
- 68
- Published applications
- 55
- Assignees
- 32
- Inventors
- 103
- Latest grant
- 10 Feb 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 1 | 0 |
| 1982 | 2 | 0 |
| 1983 | 0 | 0 |
| 1984 | 1 | 0 |
| 1985 | 4 | 0 |
| 1986 | 2 | 0 |
| 1987 | 5 | 0 |
| 1988 | 0 | 0 |
| 1989 | 3 | 0 |
| 1990 | 2 | 0 |
| 1991 | 2 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 3 | 0 |
| 1995 | 2 | 0 |
| 1996 | 3 | 0 |
| 1997 | 0 | 0 |
| 1998 | 2 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 1 |
| 2003 | 2 | 3 |
| 2004 | 3 | 7 |
| 2005 | 3 | 4 |
| 2006 | 3 | 3 |
| 2007 | 0 | 0 |
| 2008 | 2 | 2 |
| 2009 | 1 | 0 |
| 2010 | 0 | 2 |
| 2011 | 1 | 0 |
| 2012 | 1 | 1 |
| 2013 | 2 | 3 |
| 2014 | 0 | 4 |
| 2015 | 1 | 2 |
| 2016 | 1 | 1 |
| 2017 | 3 | 3 |
| 2018 | 1 | 4 |
| 2019 | 1 | 1 |
| 2020 | 2 | 3 |
| 2021 | 2 | 1 |
| 2022 | 4 | 5 |
| 2023 | 0 | 2 |
| 2024 | 1 | 0 |
| 2025 | 0 | 2 |
| 2026 | 1 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Homo-polar DC electric generator with positive electromagnetic and positive electro-mechanical feedback10 Feb 2026US 12,549,081 B2
- Systems and methods for battery impedance matching to facilitate improved battery charging23 Jul 2024US 12,046,935 B2Premergy, Inc.
- Device and method to generate and apply gravito-magnetic energy8 Nov 2022US 11,496,033 B2
- Turbofan jet engine, powered by an electric motor with power from a high efficiency electric generator16 Aug 2022US 11,418,103 B2
- Systems and methods for battery impedance matching to facilitate improved battery charging3 May 2022US 11,322,952 B2Premergy, Inc.
- Method and apparatus for reversing induction of disadvantageous emf from electrical connection moving in return flux23 Jul 2026US 2026/0213634 A1Nextpower360 Co.
- Homopolar type generators and motors18 Dec 2025US 2025/0385582 A1Nextpower360 Co.
- Homopolar type generators and motors11 Dec 2025US 2025/0379499 A1Nextpower360 Co.
- Flat dc electric machine2 Mar 2023US 2023/0067006 A1
- Turbofan jet engine, powered by an electric motor with power from a high efficiency electric generator5 Jan 2023US 2023/0006533 A1Holcomb Scientific Research Limited
Most cited
By later US patents
- Direct current homopolar machine95US 5,587,618 A1996
- Homopolar dynamo-electric machines40US 3,944,865 AReyrolle Parsons Limited · 1976
- Electrical machine29US 5,049,771 AIAP Research, Inc. · 1991
- Homopolar machine with shaft axial thrust compensation for reduced thrust bearing wear and noise29US 6,856,062 B2General Atomics · 2005
- Homopolar machine23US 5,530,309 ABoard of Regents, The University of Texas System · 1996