F04C 2220/50
Pumps with means for introducing gas under pressure for ballasting
F04C2220/50 (Pumps with means for introducing gas under pressure for ballasting) appears on 27 US grants and 21 published applications in this corpus.
Search patents in F04C- Granted patents
- 27
- Published applications
- 21
- Assignees
- 16
- Inventors
- 45
- Latest grant
- 10 Feb 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 3 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 0 | 0 |
| 1989 | 1 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 1 | 0 |
| 1999 | 1 | 0 |
| 2000 | 2 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 1 | 0 |
| 2005 | 0 | 1 |
| 2006 | 0 | 2 |
| 2007 | 1 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 0 |
| 2012 | 0 | 0 |
| 2013 | 0 | 0 |
| 2014 | 0 | 1 |
| 2015 | 0 | 1 |
| 2016 | 1 | 2 |
| 2017 | 1 | 0 |
| 2018 | 1 | 0 |
| 2019 | 0 | 2 |
| 2020 | 1 | 0 |
| 2021 | 0 | 2 |
| 2022 | 2 | 2 |
| 2023 | 2 | 2 |
| 2024 | 3 | 4 |
| 2025 | 1 | 1 |
| 2026 | 1 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Rotary piston compressor/pump/blower with a ventilation channel10 Feb 2026US 12,546,315 B2Gardner Denver Schopfheim GmbH
- Rotary piston compressor/pump/blower with a ventilation channel14 Jan 2025US 12,196,204 B2Gardner Denver Schopfheim GmbH
- Vacuum pump with an oil management system31 Dec 2024US 12,180,962 B2Fieldpiece Instruments, Inc.
- Liquid containing gas bubbles production apparatus19 Nov 2024US 12,145,116 B2KYB Corporation
- Rotary piston compressor/pump/blower with a ventilation channel23 Jan 2024US 11,879,458 B2Gardner Denver Schopfheim GmbH
- Rotary piston compressor/pump/blower with a ventilation channel18 Jun 2026US 2026/0168495 A1
- Rotary piston compressor/pump/blower with a ventilation channel8 May 2025US 2025/0146489 A1Gardner Denver Schopfheim GmbH
- Method for operating a vacuum pump and vacuum pump12 Sep 2024US 2024/0302852 A1
- Rotary piston compressor/pump/blower with a ventilation channel4 Apr 2024US 2024/0110564 A1Gardner Denver Schopfheim GmbH
- Vacuum pump with an oil management system4 Apr 2024US 2024/0110566 A1Fieldpiece Instruments, Inc.
Most cited
By later US patents
- Cooling structure for an oil sealed rotary vacuum pump25US 4,283,167 AVarian Associates, Inc. · 1981
- Oil flow metering structure for oil sealed mechanical vacuum vane pump13US 4,276,005 AVarian Associates, Inc. · 1981
- Vacuum pump9US 6,123,516 ALeybold Vakuum GmbH · 2000
- Liquid ring compressor including a calibrated gas input opening8US 4,083,658 ASiemens Aktiengesellschaft · 1978
- Gas ballast for oil sealed mechanical vacuum vane pump8US 4,268,230 AVarian Associates, Inc. · 1981