Sensor using electro active curved helix and double helix
US7069795B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 2002 |
| Grant date | Jul 4, 2006 |
| Priority date | — |
| Expiry date | Jun 19, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Various sensors use an electro-active device (11) electrically connected to a detector circuit. The electro-active device (11) comprises an electro-active structure in the form of a continuous electro-active member (12) curving in a helix around a minor axis (13) which is in itself curved for example in a helix around a major axis (14). On activation by relative displacement of the ends (16) of the device (11), the electro-active structure twists around the minor axis due to the fact that the minor axis (13) is curved. The continuous member (12) has a bender construction of a plurality of layers (21) and (22) including at least one layer of electro-active material so that concomitantly with the twisting the continuous member (12) bends generating an electrical signal detected by the detector circuit. The electro-active device (11) is advantageous as a sensing element in a sensor because it has a large displacement, high sensitivity and low compliance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.