Wax elements as passive control devices in fuel cell power systems
US8785067B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 2007 |
| Grant date | Jul 22, 2014 |
| Priority date | — |
| Expiry date | Sep 22, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/50
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A fuel cell system that employs one or more wax elements to provide passive control. In one embodiment, a wax element device is positioned within a coolant stream pipe. The wax element device includes a wax element positioned within a container. An electrically conductive rod is positioned within the wax element and extends out of the pipe. As the wax element expands and contracts in response to temperature changes in the cooling fluid, the rod moves up and down to make various electrical contacts and control the various devices, such a coolant pump and a coolant fan. In another embodiment, the rod extends into a cathode exhaust pipe of the fuel cell system, and is coupled to a back-pressure valve therein. As the temperature of the cooling fluid changes, the wax element expands and contracts to control the position of the back-pressure valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.