Expandable cushion plunger for piston and cylinder devices
US4352318A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1980 |
| Grant date | Oct 5, 1982 |
| Priority date | — |
| Expiry date | Mar 6, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B15/222
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An expandable cushion plunger for use with a fluid pressure driven piston and cylinder device includes a cushion sleeve mounted on a piston rod in floating relation thereto, and having a skirt, the interior of which is exposed to the cushioning fluid within the cylinder. As the piston nears the end of its stroke, the sleeve begins to enter a fluid exit port, trapping fluid between the piston and the cylinder head, which will slow and cushion the piston travel as it approaches the cylinder head. As the sleeve continues to enter the fluid exit port, the pressure of the trapped fluid increases due to the smaller size of the annular orifice between the sleeve and the port as compared with the port size. The cushion sleeve may expand under influence of increased pressure, further restricting the flow of pressurized fluid through the annular orifice to provide smooth deceleration of the piston as it reaches the end of its stroke and comes to rest against the cylinder head without undesirable impact.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.