Liquid crystal liquid level indicator
US6260414A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1998 |
| Grant date | Jul 17, 2001 |
| Priority date | — |
| Expiry date | Oct 22, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/22
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A cholesteric liquid crystal fluid level indicator that determines the level of a cooled liquid, such as beer, in a closed, opaque keg when placed in thermal contact with the exterior surface of the keg, by producing a color change that is a function of the liquid temperature when the liquid is within a predetermined temperature range, the indicator comprises a multiple level strip having a top transparent layer, liquid crystal layer, a black background layer and an attachment layer employing a protected adhesive on its bottom surface for removably attaching the strip to the keg, the instant invention employs a heat conducting adhesive on the attachment layer and for securing certain layers in the strip, such as the liquid crystal layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.