F04C 23/001
Combinations of two or more pumps, each being of rotary-piston or oscillating-piston
Official title: {of similar working principle}
F04C23/001 (Combinations of two or more pumps, each being of rotary-piston or oscillating-piston) appears on 830 US grants and 897 published applications in this corpus.
Search patents in F04C- Granted patents
- 830
- Published applications
- 897
- Assignees
- 255
- Inventors
- 1,511
- Latest grant
- 22 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 1 | 0 |
| 1978 | 3 | 0 |
| 1979 | 0 | 0 |
| 1980 | 7 | 0 |
| 1981 | 2 | 0 |
| 1982 | 1 | 0 |
| 1983 | 1 | 0 |
| 1984 | 2 | 0 |
| 1985 | 7 | 0 |
| 1986 | 1 | 0 |
| 1987 | 2 | 0 |
| 1988 | 3 | 0 |
| 1989 | 4 | 0 |
| 1990 | 6 | 0 |
| 1991 | 11 | 0 |
| 1992 | 13 | 0 |
| 1993 | 6 | 0 |
| 1994 | 11 | 0 |
| 1995 | 5 | 0 |
| 1996 | 7 | 0 |
| 1997 | 10 | 0 |
| 1998 | 12 | 0 |
| 1999 | 6 | 0 |
| 2000 | 11 | 0 |
| 2001 | 16 | 5 |
| 2002 | 19 | 33 |
| 2003 | 29 | 27 |
| 2004 | 28 | 46 |
| 2005 | 14 | 52 |
| 2006 | 33 | 50 |
| 2007 | 32 | 18 |
| 2008 | 18 | 53 |
| 2009 | 23 | 31 |
| 2010 | 24 | 45 |
| 2011 | 8 | 27 |
| 2012 | 33 | 27 |
| 2013 | 23 | 26 |
| 2014 | 20 | 39 |
| 2015 | 25 | 29 |
| 2016 | 25 | 27 |
| 2017 | 32 | 49 |
| 2018 | 28 | 38 |
| 2019 | 40 | 38 |
| 2020 | 28 | 44 |
| 2021 | 28 | 42 |
| 2022 | 48 | 36 |
| 2023 | 42 | 34 |
| 2024 | 41 | 23 |
| 2025 | 24 | 30 |
| 2026 | 15 | 28 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Vertical type compressor and laundry treating apparatus having the same22 Sep 2026US 12,742,456 B2LG Electronics Inc.
- Throttle valve for coolant circulation system18 Aug 2026US 12,710,056 B2Ingersoll-Rand Industrial U.S., Inc.
- Method for controlling a compressor installation4 Aug 2026US 12,698,766 B2Kaeser Kompressoren SE
- Method for operating a pump system9 Jun 2026US 12,650,120 B2Leybold Aktiengesellschaft
- Rotary compressor for rapid freezing appliances9 Jun 2026US 12,650,128 B2Rechi Precision Co., Ltd.
- Scroll compressor1 Oct 2026US 2026/0298234 A1Ishikawa Energy Research Co., Ltd.
- Pump body assembly, compressor and air conditioner17 Sep 2026US 2026/0275987 A1Gree Electric Appliances, Inc. of Zhuhai
- Vacuum pump20 Aug 2026US 2026/0243257 A1Pfeiffer Vacuum GmbH
- Gas Compressor20 Aug 2026US 2026/0243258 A1Hitachi Industrial Equipment Systems Co., Ltd.
- Simultaneous compressor-expander13 Aug 2026US 2026/0235127 A1
Most cited
By later US patents
- Two stage screw type vacuum pump with motor in-between the stages140US 5,846,062 AEbara Corporation · 1998
- Oil level control system129US 6,125,642 ASporlan Valve Company · 2000
- Compressor with control and protection system115US 6,302,654 B1Copeland Corporation · 2001
- Capacity modulation for plural compressors70US 6,672,846 B2Copeland Corporation · 2004
- Scroll compressor of two-stage compression type having an improved volumetric efficiency52US 5,304,047 ADaikin Industries, Ltd. · 1994