H01F 29/02
Variable transformers or inductances not covered by group h01f21/00: with tappings on
Official title: with tappings on coil or winding; with provision for rearrangement or interconnection of windings
H01F29/02 (Variable transformers or inductances not covered by group h01f21/00: with tappings on) appears on 382 US grants and 373 published applications in this corpus.
Search patents in H01F- Granted patents
- 382
- Published applications
- 373
- Assignees
- 208
- Inventors
- 780
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 4 | 0 |
| 1977 | 4 | 0 |
| 1978 | 2 | 0 |
| 1979 | 2 | 0 |
| 1980 | 6 | 0 |
| 1981 | 5 | 0 |
| 1982 | 5 | 0 |
| 1983 | 2 | 0 |
| 1984 | 3 | 0 |
| 1985 | 7 | 0 |
| 1986 | 5 | 0 |
| 1987 | 4 | 0 |
| 1988 | 1 | 0 |
| 1989 | 1 | 0 |
| 1990 | 4 | 0 |
| 1991 | 2 | 0 |
| 1992 | 2 | 0 |
| 1993 | 0 | 0 |
| 1994 | 2 | 0 |
| 1995 | 1 | 0 |
| 1996 | 1 | 0 |
| 1997 | 4 | 0 |
| 1998 | 4 | 0 |
| 1999 | 2 | 0 |
| 2000 | 2 | 0 |
| 2001 | 0 | 1 |
| 2002 | 1 | 3 |
| 2003 | 6 | 7 |
| 2004 | 3 | 11 |
| 2005 | 8 | 16 |
| 2006 | 11 | 13 |
| 2007 | 14 | 9 |
| 2008 | 10 | 11 |
| 2009 | 10 | 23 |
| 2010 | 9 | 10 |
| 2011 | 11 | 8 |
| 2012 | 18 | 7 |
| 2013 | 11 | 29 |
| 2014 | 20 | 24 |
| 2015 | 13 | 19 |
| 2016 | 18 | 22 |
| 2017 | 18 | 19 |
| 2018 | 16 | 12 |
| 2019 | 21 | 18 |
| 2020 | 16 | 19 |
| 2021 | 17 | 14 |
| 2022 | 9 | 15 |
| 2023 | 13 | 23 |
| 2024 | 14 | 15 |
| 2025 | 12 | 12 |
| 2026 | 8 | 13 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Monitoring a transformer comprising a tap changer6 Oct 2026US 12,754,255 B2Hitachi Energy Ltd
- Method and device for changing a transformation ratio, an impedance, or a voltage used for excitation6 Oct 2026US 12,756,193 B2Reinhausen GmbH
- Tap changer and a transformer arrangement comprising the tap changer29 Sep 2026US 12,749,618 B2Hitachi Energy Ltd
- On-load tap changer and tap-changing transformer having an on-load tap changer29 Sep 2026US 12,749,634 B2Maschinenfabrik Reinhausen GmbH
- On-load tap changer and tap-changing transformer having an on-load tap changer18 Aug 2026US 12,712,136 B2Maschinenfabrik Reinhausen GmbH
- Device Having a Multimode Antenna With Variable Width of Conductive Wire17 Sep 2026US 2026/0279661 A1NuCurrent, Inc.
- Voltage amplitude and phase adjustment apparatus and method, and computer device and storage medium27 Aug 2026US 2026/0254344 A1
- Method for producing an electrical regulation winding, prefabricated conductor arrangement and electric regulation winding16 Jul 2026US 2026/0204475 A1Hitachi Energy Ltd
- Ac powered nano-processor11 Jun 2026US 2026/0161208 A1PI Invent Inc.
- Three-dimensional vertical inductors with magnetic core11 Jun 2026US 2026/0162861 A1Microchip Technology Incorporated
Most cited
By later US patents
- Planar transformer power supply266US 7,502,234 B2Aaron Medical Industries, Inc. · 2009
- High power battery powered RF amplifier topology200US 10,159,524 B2Ethicon, Inc. · 2018
- Variable output three-phase transformer193US 6,087,738 ARobicon Corporation · 2000
- Power supply circuit with symmetrically tapped auto-transformer184US 4,906,859 ANEC Corporation · 1990
- Method for operation of multi-layer-multi-turn high efficiency inductors153US 8,710,948 B2NuCurrent, Inc. · 2014