H01F 27/20
Cooling by special gases or non-ambient air
H01F27/20 (Cooling by special gases or non-ambient air) appears on 39 US grants and 43 published applications in this corpus.
Search patents in H01F- Granted patents
- 39
- Published applications
- 43
- Assignees
- 37
- Inventors
- 128
- Latest grant
- 28 Jul 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1981 | 1 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 1 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 1 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 1 |
| 2004 | 0 | 0 |
| 2005 | 2 | 1 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 0 |
| 2012 | 0 | 2 |
| 2013 | 2 | 0 |
| 2014 | 1 | 2 |
| 2015 | 1 | 1 |
| 2016 | 1 | 4 |
| 2017 | 3 | 7 |
| 2018 | 1 | 5 |
| 2019 | 3 | 2 |
| 2020 | 10 | 4 |
| 2021 | 2 | 1 |
| 2022 | 2 | 4 |
| 2023 | 0 | 2 |
| 2024 | 3 | 5 |
| 2025 | 1 | 2 |
| 2026 | 2 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Electric device with forced direct cooling28 Jul 2026US 12,695,019 B2Siemens Energy Global GmbH & Co. KG
- Shunt reactor with auxiliary power13 Jan 2026US 12,525,382 B2Hitachi Energy Ltd
- Transformer cooling system and transformer installation20 May 2025US 12,308,159 B2Hitachi Energy Ltd
- Electrical device having heat generating components with improved heat removal using turbulent flow13 Aug 2024US 12,062,478 B2
- Cooling structure for transformer9 Jul 2024US 12,033,780 B2TMEIC Corporation
- Integrated gas sensing and regulation system8 May 2025US 2025/0147473 A1Prolec-GE Waukesha, Inc.
- Coil device for generating plasma and semiconductor equipment20 Mar 2025US 2025/0095962 A1Beijing Naura Microelectronics Equipment Co., Ltd.
- The insulating gas mixture for replacing sf6, as well as its formulation method and application24 Oct 2024US 2024/0355538 A1Wuhan University
- Induction coil apparatus and radio frequency matching network incorporating the same25 Jul 2024US 2024/0249869 A1ASM IP Holding B. V.
- Insulation assembly, transformer assembly, and dry type transformer4 Jul 2024US 2024/0222000 A1Hitachi Energy Ltd
Most cited
By later US patents
- Transformer with windings completely embedded in cast resin20US 4,488,134 ATransformatoren Union Aktiengesellschaft · 1984
- Method for monitoring unusual signs in gas-charged apparatus17US 5,128,269 AKabushiki Kaisha Toshiba · 1992
- Gas-insulated electric apparatus16US 5,252,778 AKabushiki Kaisha Toshiba · 1993
- System, method and apparatus for transformer cooling8US 8,461,953 B12013
- Electrical reactor with foil windings7US 4,307,364 AWestinghouse Electric Corp. · 1981