Claims
- 1. A pneumatic spring for absorbing an external force by compressing a gaseous fluid trapped therein comprising
- an outer housing comprising a base wall and a side wall defining a first cylinder having an open end,
- a second cylinder slidingly and sealingly positioned in the first cylinder,
- seal means between said cylinders,
- said second cylinder having a cylindrical side wall and inner and outer end walls,
- a rod extending from the base wall of the first cylinder through the inner end wall of the second cylinder,
- a piston fixed on the rod within the second cylinder,
- thereby defining a first chamber between the base wall of the first cylinder and the inner end wall of the second cylinder and a second chamber between the piston on the rod and the outer end wall of the second cylinder,
- said chambers being isolated from one another and being normally charged with gaseous fluid such that fluid will not flow between said chambers during operation,
- said base wall having a single inlet and passages selectively connected to said inlet for supplying fluid under pressure to each of said chambers,
- a valve in each passage entirely within said base wall providing gaseous fluid under pressure to each passage such that the chambers remain isolated from one another whereby when a force is applied to move the second cylinder axially inwardly of the first cylinder, the pressures in the two chambers are built up independently of one another,
- each said valve including check valve means and pressure relief valve means for relieving the pressure in its respective chamber.
- 2. The pneumatic spring set forth in claim 1 wherein each said valve comprises a ball check valve for controlling the flow of fluid into each said chamber and a shuttle valve for controlling excessive pressure in its chamber, said ball check valve being positioned in such shuttle valve.
- 3. A pneumatic spring for absorbing an external force by compressing a gaseous fluid trapped therein comprising
- an outer housing comprising a base wall and a side wall defining a first cylinder having an open end,
- a second cylinder slidingly and sealingly positioned in the first cylinder,
- seal means between said cylinders,
- said second cylinder having a cylindrical side wall and inner and outer ends walls,
- a rod extending from the base wall of the first cylinder through the inner end wall of the second cylinder,
- a piston fixed on the rod within the second cylinder,
- thereby defining a first chamber between the base wall of the first cylinder and the inner end wall of the second cylinder and a second chamber between the piston on the rod and the outer end wall of the second cylinder,
- said chambers being isolated from one another and being normally charged with gaseous fluid such that fluid will not flow between said chambers during operation,
- said base wall having a first inlet and passages selectively connected to said inlet for supplying fluid under pressure to each of said chambers,
- a valve in each passage providing gaseous fluid under pressure to each passage such that the chambers remain isolated from one another whereby when a force is applied to move the second cylinder axially inwardly of the first cylinder, the pressure in the two chambers are built up independently of one another,
- each said valve including check valve means and pressure relief valve means for relieving the pressure in its respective chamber,
- each said valve comprising a ball check valve for controlling the flow of fluid into its respective chamber and a shuttle valve for controlling excessive pressure in its respective chamber, said ball check valve being positioned in such shuttle valve,
- said first inlet extending from the bottom of said base wall, said base wall including a second inlet extending from the side of said base wall and communicating with said passages such that one of the inlets can be used selectively by obstructing the other inlet.
Parent Case Info
This application is a continuation-in-part of U.S. application Ser. No. 180,133 filed Aug. 21, 1980, now abandoned.
US Referenced Citations (11)
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
180133 |
Aug 1980 |
|