Constant length strut
US4742261A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1986 |
| Grant date | May 3, 1988 |
| Priority date | — |
| Expiry date | Dec 10, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/505
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A constant length strut includes an axially elongated body having a fixed attachment point at one end and an attachment point carried at its opposite end and supported for axial movement toward and away from the fixed attachment point. A quartz reference rod is connected at one end to one attachment point and extends internally for substantially the length of the strut. The free end of the reference rod moves axially lengthwise relative to the other attachment point as the strut changes length due to thermal expansion and contraction or tensile and compressive loading. A positional displacement transducer senses this relative movement. An electrical signal directly proportional to the displacement excites a linear actuator connected between the telescopic attachment point and the strut body to provide a corrective displacement to maintain the strut at a constant length.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.