Return apparatus
US4935985A · kind A · utility
Inventor
Key dates
| Filing date | May 25, 1989 |
| Grant date | Jun 26, 1990 |
| Priority date | — |
| Expiry date | May 25, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16F5/00
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A return apparatus includes a first hollow cylindrical member and a second hollow cylindrical member sleeved in the first cylindrical member to create a telescoping movement in a sealed relationship. The first cylindrical member has a first and a second closed end to define a first sealed chamber. The second cylindrical member has a first closed end protruding beyond the first closed end of the first cylindrical member and a second closed end having a flange radially extended therefrom to seal and engage movably with the inner face of the first cylindrical member in the first chamber. A floating piston is mounted in the axial bore of the second cylindrical member defining a second chamber and a third chamber. The third chamber is provided with a compressible gas. The first and second chambers are filled with fluid under the pressure of the compressible gas. In this way, the second cylindrical member can be retracted to an original position after it is pulled outward by an axially external force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.