Electrically controlled liquid-crystal heat valve
US5222548A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 1992 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | May 26, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S165/905
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
An improved electrically controlled thermotropic liquid-crystal heat valve to control the flow of heat between two bodies of different temperatures by interposing therebetween a fluid layer of liquid-crystal material having a nematic temperature range that includes the temperature of both bodies. This type of heat valve has particular application to any free-swimming divers' diving garments, to provide some thermal protection against the cold ambient water. The heat valve uses stable liquid-crystal materials encapsulated in a sealed environment, with the valves' electrodes being shielded and not in direct electrical contact with the liquid-crystal material. This arrangement essentially completely eliminates the electrochemical effects which can otherwise degrade the liquid-crystal materials, so that the liquid crystal may function for a very long time. The valve is electrically controlled between the respective two different modes of its open and closed conditions, the open mode occurring when a low frequency AC field is applied to one of the liquid crystal materials; and the closed mode occurring when a high frequency field is applied to effect reorientation of the molecules of th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.