Self-contained thermal actuator
US7469841B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2004 |
| Grant date | Dec 30, 2008 |
| Priority date | — |
| Expiry date | Mar 4, 2026 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF03G7/06113
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A self-contained thermal actuator positions the piston return member inside the actuator cup. The inventive configuration eliminates the guide and diaphragm seal that closed the open end of the wax filled cup in the typical thermal actuator configuration. The piston and an O-ring seal seated in an annular recess defined by the piston contain the thermally responsive wax. A return member within the cup and engaged between axially spaced, radially overlapping shoulders on the cup and piston biases the piston toward its pre-actuation position. The return member may be a spring or an elastomeric O-ring that also seals the thermal actuator against intrusion of contaminants from the use environment. The piston is closely received in the cup for guided axial reciprocation therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.