H01F 29/04
Having provision for tap-changing without interrupting the load current
Official title: having provision for tap-changing without interrupting the load current
H01F29/04 (Having provision for tap-changing without interrupting the load current) appears on 148 US grants and 147 published applications in this corpus.
Search patents in H01F- Granted patents
- 148
- Published applications
- 147
- Assignees
- 67
- Inventors
- 320
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 1 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 3 | 0 |
| 1981 | 3 | 0 |
| 1982 | 2 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 2 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 1 | 0 |
| 1991 | 1 | 0 |
| 1992 | 1 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 2 | 0 |
| 1998 | 2 | 0 |
| 1999 | 1 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 1 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 1 | 3 |
| 2005 | 1 | 1 |
| 2006 | 3 | 3 |
| 2007 | 0 | 1 |
| 2008 | 3 | 2 |
| 2009 | 2 | 18 |
| 2010 | 1 | 2 |
| 2011 | 5 | 4 |
| 2012 | 12 | 4 |
| 2013 | 5 | 8 |
| 2014 | 4 | 14 |
| 2015 | 10 | 13 |
| 2016 | 11 | 11 |
| 2017 | 10 | 6 |
| 2018 | 6 | 5 |
| 2019 | 11 | 4 |
| 2020 | 6 | 8 |
| 2021 | 6 | 6 |
| 2022 | 3 | 9 |
| 2023 | 6 | 12 |
| 2024 | 7 | 5 |
| 2025 | 6 | 5 |
| 2026 | 3 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Method and device for changing a transformation ratio, an impedance, or a voltage used for excitation6 Oct 2026US 12,756,193 B2Reinhausen GmbH
- On-load tap changer and tap-changing transformer having an on-load tap changer29 Sep 2026US 12,749,634 B2Maschinenfabrik Reinhausen GmbH
- Full range boosting device for accumulator of on-load tap changer, accumulator, and on-load tap changer21 Apr 2026US 12,609,240 B2Beijing Aerospace Control Device Institute
- On-load tap changer and method for actuating an on-load tap changer21 Oct 2025US 12,451,299 B2Maschinenfabrik Reinhausen GmbH
- On-load tap changer and method for actuating an on-load tap changer2 Sep 2025US 12,406,801 B2Maschinenfabrik Reinhausen GmbH
- On-load tap-changer, method for actuating an on-load tap-changer, and tap-changing transformer having an on-load tap-changer23 Apr 2026US 2026/0112539 A1Maschinenfabrik Reinhausen GmbH
- Electrical operating means comprising a tap changer5 Feb 2026US 2026/0038736 A1
- On-load tap-changer25 Dec 2025US 2025/0391617 A1West Journey Corporation
- Method for adapting a target voltage value for controlling a tap-changing transformer, and device for adapting a target voltage value for controlling a tap-changing transformer13 Nov 2025US 2025/0350220 A1Maschinenfabrik Reinhausen GmbH
- Method and device for changing a transformation ratio, an impedance, or a voltage used for excitation23 Oct 2025US 2025/0330018 A1Maschinenfabrik Reinhausen GmbH
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- Ranging methods for developing wellbores in subsurface formations87US 8,011,451 B2Shell Oil Company · 2011
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