Spence Engineering Company, Inc.
4Patents
2Active
4Granted
34Portfolio score
Filing activity: Jun 18, 1975 → Jan 30, 2009 · 2 expiring within 5 years
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4040440A | Silenced valve construction | Emerging Cross-Sectional Technologies | 7 | Expired |
| US4561458A | Steam-metering method and apparatus | Emerging Cross-Sectional Technologies | 3 | Expired |
| US8057192B2 | Cyclic condensate pump having a three-way valve | Emerging Cross-Sectional Technologies | 2 | Active |
| US7491035B2 | Cyclic condensate pump having a three-way valve | Mechanical Engineering; Lighting; Heating | 0 | Active |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.