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US 4,072,288 AGranted
Chair with pneumatically adjustable seat height and back support inclination
AssigneeStabilus GmbH
InventorsWinfried Wirges, Herbert Freitag
Life of this patent
Estimating the term…
Abstract
The height of a chair and the inclination of its back support may be varied by changing the respective, effective lengths of two pneumatic springs whose assembly forms the chair leg. The cylinder of one spring is coaxially received in the cylinder or the hollow piston rod of the other spring, and relative axial movement of the received spring and the receiving element of the other spring is limited or entirely prevented. A valve connects the two compartments separated in the cylinder of each spring and may be operated by a mechanism separate from the valve operating mechanism of the other spring.
Claims17
A pneumatic spring assembly comprising:
- a. a first pneumatic spring including a first cylinder portion having an axis and defining a first cavity therein, a first piston axially movable in said cavity and axially separating two compartments of said cavity, a first piston rod portion secured to said piston for joint axial movement and axially projecting from said cavity, a gas under a pressure higher than atmospheric pressure filling said compartments, first valve means connecting said compartments, and first manually operable means for opening and closing said valve means and for thereby controlling flow of said gas between said compartments;
- b. a second pneumatic spring including a second cylinder portion having an axis and defining a second cavity therein, a second piston axially movable in said second cavity and axially separating two compartments of said second cavity, a second piston rod portion secured to said second piston for joint axial movement and axially projecting from said second cavity, a gas under a pressure higher than atmospheric pressure filling said compartments of said second cavity, second valve means connecting said compartments of said second cavity for controlling flow of said gas therebetween, and second manually operable means for opening and closing said second valve means while said first valve means are open and while said first valve means are closed,
- 1. one of said portions of said second pneumatic spring being received in one of said portions of said first pneumatic spring;
- and
- c. securing means connecting said one portion of said second pneumatic spring to said one portion of said first pneumatic spring and limiting relative axial movement of the connected portions.
2 more elements
An assembly comprising:
- a. a first pneumatic spring including a first cylinder member having an axis and defining a first cavity therein, a first piston axially movable in said cavity and axially separating two compartments of said cavity, a first piston rod member secured to said piston for joint axial movement and axially projecting from said cavity, first valve means communicating with said compartments, and first manually operable means for opening and closing said valve means;
- b. a second pneumatic spring including a second cylinder member having an axis and defining a second cavity therein, a second piston axially movable in said second cavity and axially separating two compartments of said second cavity, a second piston rod member secured to said second piston for joint axial movement and axially projecting from said second cavity, second valve means communicating with said compartments of said second cavity, and second manually operable means for opening and closing said second valve means,
- 1. said second pneumatic spring being received in one of said members of said first pneumatic spring;
- c. securing means connecting one of said members of said second pneumatic spring to said one member of said first pneumatic spring and limiting relative axial movement of the connected members;
- d. a base secured to one of said members of said first pneumatic spring;
- e. a carrier member secured to the other member of said first pneumatic spring for joint axial movement relative to said one member;
- f. a supporting member movably mounted on said carrier member;
- and
- g. motion transmitting means connecting said supporting member to the other member of said second pneumatic spring for moving said supporting member relative to said carrier member in response to axial movement of said second piston in said second cavity.
6 more elements
Dependencies are inferred from the claim text.