Freeze protection apparatus for solar collectors
US4450868A · kind A · utility
Inventors
Key dates
| Filing date | Apr 30, 1981 |
| Grant date | May 29, 1984 |
| Priority date | — |
| Expiry date | Apr 30, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/86879
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A freeze protection system allows the working fluid contained in the communicating tubes of the solar collector to drain from both the input and output tubes of the collector when a first predetermined temperature of the working fluid is detected and to fill the collector via both the input and output tubes when a second predetermined temperature is detected. The invention includes valve mechanisms, of the spool valve variety, that communicate the working fluid to be heated to the collector and therefrom to a storage tank, a valve actuator and a sensor. The actuator moves a valve element from a first position for communicating working fluid to be heated from a source to the input tube of the collector and for communicating heated working fluid from the output tube of the collector to a storage facility to a second position for interrupting fluid communication from the source to the collector and for communicating both the input and output tubes of the collector to a drainpipe--draining the collector of working fluid--when the first predetermined temperature level is detected by the sensor. Upon detection of the second predetermined temperature level the sensor causes the actuator t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.