Axially contractable actuator
US4939982A · kind A · utility
Inventors
Key dates
| Filing date | Oct 16, 1985 |
| Grant date | Jul 10, 1990 |
| Priority date | — |
| Expiry date | Oct 16, 2005 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B15/103
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An axially contractable actuator which includes an elongated hollow enclosure (14) formed by a fluid impermeable substantially non-elastic material and having a plurality of protrusions each with respective bases having more than three sides. Each base side (48) of a protrusion is attached to a base side (48) of an adjacent protrusion by a flexible seam of continuous fold (55). Each protrusion is foldable about a plane dividing the protrusion into two parts from an axially-extended condition in which the base sides are substantially parallel, to an axially-contracted condition in which the protrusion encloses a volume larger than that enclosed in the axially-extended condition. A pair of axially-aligned end terminations (18) are formed at each end of the enclosure with one of the end terminations being hollow. A pair of end connectors are each coupled to a respective end termination with one of the end connectors having an axial bore providing fluid communication between an interior of the hollow enclosure as a source of pressurized fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.