H01T 13/44
With transformers
Official title: with transformers, e.g. for high-frequency ignition
H01T13/44 (With transformers) appears on 145 US grants and 117 published applications in this corpus.
Search patents in H01T- Granted patents
- 145
- Published applications
- 117
- Assignees
- 57
- Inventors
- 261
- Latest grant
- 9 Dec 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1989 | 1 | 0 |
| 1990 | 2 | 0 |
| 1991 | 3 | 0 |
| 1992 | 2 | 0 |
| 1993 | 2 | 0 |
| 1994 | 3 | 0 |
| 1995 | 6 | 0 |
| 1996 | 0 | 0 |
| 1997 | 1 | 0 |
| 1998 | 0 | 0 |
| 1999 | 2 | 0 |
| 2000 | 2 | 0 |
| 2001 | 8 | 0 |
| 2002 | 6 | 3 |
| 2003 | 4 | 9 |
| 2004 | 8 | 9 |
| 2005 | 6 | 3 |
| 2006 | 7 | 4 |
| 2007 | 6 | 6 |
| 2008 | 3 | 3 |
| 2009 | 3 | 4 |
| 2010 | 2 | 4 |
| 2011 | 5 | 0 |
| 2012 | 2 | 5 |
| 2013 | 4 | 7 |
| 2014 | 4 | 12 |
| 2015 | 5 | 8 |
| 2016 | 9 | 5 |
| 2017 | 8 | 16 |
| 2018 | 11 | 8 |
| 2019 | 11 | 4 |
| 2020 | 4 | 2 |
| 2021 | 0 | 0 |
| 2022 | 2 | 1 |
| 2023 | 1 | 1 |
| 2024 | 1 | 1 |
| 2025 | 1 | 2 |
By publication year. Applications have been published since 2001.
Recent patents
- Ignition system using push-pull transformer9 Dec 2025US 12,494,622 B2
- System and method for spark plug identification and engine monitoring14 May 2024US 11,984,705 B2Ai Alpine US Bidco Inc
- Focused microwave or radio frequency ignition and plasma generation21 Feb 2023US 11,585,312 B1Southwest Research Institute
- High voltage ignition coil with improved insulating characteristics5 Jul 2022US 11,380,479 B2
- Ignition coil15 Mar 2022US 11,276,524 B2Denso Corporation
- Ignition system using push-pull transformer21 Aug 2025US 2025/0266665 A1Marshall Electric Corp.
- Tubular structure adapted to at least partly enclose a pencil coil for internal combustion engines14 Aug 2025US 2025/0257683 A1Sem AB
- Spark plug connector1 Aug 2024US 2024/0258772 A1
- Focused Microwave or Radio Frequency Ignition and Plasma Generation16 Mar 2023US 2023/0083067 A1Southwest Research Institute
- System and method for spark plug identification and engine monitoring10 Mar 2022US 2022/0077660 A1Ai Alpine US Bidco Inc
Most cited
By later US patents
- Engine ignition coil device34US 5,870,012 AToyo Denso Kabushiki Kaisha · 1999
- Integrated spark plug ignition coil with pressure sensor for an internal combustion engine31US 6,119,667 ADelphi Technologies, Inc. · 2000
- Ignition system for internal combustion engine28US 5,146,906 AHonda Giken Kogyo Kabushiki Kaisha · 1992
- Ignition coil for internal combustion engine27US 5,170,767 ANippondenso Co., Ltd. · 1992
- Electrically wiring parts mounted on an engine27US 5,390,648 AYazaki Corporation · 1995