Patent US3787019A successfully refreshed from Google Patents.
US3787019A
Expired / Lapsed
US
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Supporting element of adjustable length
Assignee: Stabilus Industrie und Handels GmbH
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Filing: 1972-04-03
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Granted: 1974-01-22
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Expires: 1992-04-03
Abstract
Abstract A normally upright, telescopically adjustable, supporting element, such as a leg for a stool, has a cylinder whose cavity is axially divided into two chambers by a partition. The lower chamber is liquid-filled, the upper chamber contains liquid under the pressure of a gas cushion, and the two chambers may be connected by a valve in the partition. The position of a plunger axially projecting from the lower chamber is generally determined by the amount of non-compressible liquid in the lower chamber, but limited axial movement is made possible by a gas cell partly bounded by the plunger and otherwise by a sealing member separating the gas in the cell from the liquid in the lower chamber.
Inventors
- 👤 H Freitag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:31
CPC Classifications
A; A47; A47C; A47C3/00; A47C3/20; A47C3/30; A47B; A47B9/00; A47B9/10; B; B60; B60N; B60N2/00; B60N2/02; B60N2/04; B60N2/16; B60N2/1635; B60N2/1665
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
259 words
A supporting element of adjustable length comprising, in combination: a. a cylinder member having an axis and defining a sealed cavity therein; b. a partition fixed to said cylinder member in said cavity and axially dividing the cavity into a first chamber and a second chamber; c. valve means operatively interposed between said chambers and movable between respective open and closed positions in which said valve means connects said chambers and seals said chambers from each other; d. valve operating means accessible outside said cavity for moving said valve means between said positions thereof; e. a first body of liquid in said first chamber; f. an amount of a gas under a pressure higher than atmospheric pressure in pressure-transmitting relationship to said body of liquid; g. a plunger member axially movable in said cylinder member, 1. said plunger member having respective axially terminal portions in said second chamber and outside said cylinder; h. a second body of liquid substantially completely filling the remainder of said second chamber and communicating with said first body in said open position of the valve means, 1. whereby said gas in the open position of the valve means exerts a first axial force on said plunger member in a direction outward of said cavity when said valve means is in the open position thereof; and i. yieldably resilient means in said second chamber opposing movement of said plunger member inward of said second chamber with a second force substantially greater than said first force when said valve means is in the closed position thereof.
Claim 2
Dependent Claim
259 words
A supporting element of adjustable length comprising, in combination: a. a cylinder member having an axis and defining a sealed cavity therein; b. a partition fixed to said cylinder member in said cavity and axially dividing the cavity into a first chamber and a second chamber; c. valve means operatively interposed between said chambers and movable between respective open and closed positions in which said valve means connects said chambers and seals said chambers from each other; d. valve operating means accessible outside said cavity for moving said valve means between said positions thereof; e. a first body of liquid in said first chamber; f. an amount of a gas under a pressure higher than atmospheric pressure in pressure-transmitting relationship to said body of liquid; g. a plunger member axially movable in said cylinder member, 1. said plunger member having respective axially terminal portions in said second chamber and outside said cylinder; h. a second body of liquid substantially completely filling the remainder of said second chamber and communicating with said first body in said open position of the valve means, 1. whereby said gas in the open position of the valve means exerts a first axial force on said plunger member in a direction outward of said cavity when said valve means is in the open position thereof; and i. yieldably resilient means in said second chamber opposing movement of said plunger member inward of said second chamber with a second force substantially greater than said first force when said valve means is in the closed position thereof.
Claim 3
Dependent Claim
65 words
An element as set forth in claim 1, wherein said yieldably resilient means are stressed during said inward movement of said plunger member and partly relaxed during movement of said plunger member outward of said second chamber when said valve means is in the closed position, said supporting element further comprising limiting means for limiting relaxation of said yieldably resilient means during said outward movement.
Claim 4
Dependent Claim
47 words
An element as set forth in claim 1, wherein said yieldably resilient means include a sealing member movable relative to said plunger member and defining therewith a cell, and a body of gas sealed from said second body of liquid in said cell by said sealing member.
Claim 5
Dependent Claim
57 words
An element as set forth in claim 3, wherein the axially terminal portion of said plunger member in said second chamber is formed with a recess therein, said sealing member being received in said recess for movement inward and outward of said recess, a portion of said recess constituting said cell and receiving said body of gas.
Claim 6
Dependent Claim
21 words
An element as set forth in claim 3, further comprising guide means axially guiding said sealing member in said second chamber.
Claim 7
Dependent Claim
47 words
An element as set forth in claim 5, wherein said sealing member is formed with a recess therein, the axially terminal portion of said plunger member being received in said recess for movement inward and outward of said recess, a portion of said recess constituting said cell.
Claim 8
Dependent Claim
47 words
An element as set forth in claim 5, wherein said guide means include a piston member axially movable in said second chamber and dividing the same into two compartments, said piston member being formed with a throttling passage connecting said compartments,said plunger member engaging said piston member.
Claim 9
Dependent Claim
54 words
An element as set forth in claim 7, wherein said sealing member is fixedly mounted on said piston member and formed with a recess therein, the axially terminal portion of said plunger member being received in said recess for movement inward and outward of said recess, a portion of Said recess constituting said cell.
Claim 10
Dependent Claim
101 words
An element as set forth in claim 3, wherein said partition is formed with a conduit axially extending thereto, said valve operating means include a rod member elongated in the direction of said axis and having respective longitudinal portions outside said cavity, in said first chamber, and in said conduit, sealing means interposed between said rod member and said cylinder member permitting axial movement of said rod member inward and outward of said cavity, said valve means including a valve member mounted on said rod member for movement therewith and sealing said conduit in the closed position of said valve means.
Claim 11
Dependent Claim
33 words
An element as set forth in claim 3, wherein said first body of liquid has a free horizontal surface in said first chamber, said amount of gas making direct contact with said surface.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |