EP0891727A2 - Gasdruckfeder, insbesondere für Bürostühle - Google Patents
Gasdruckfeder, insbesondere für Bürostühle Download PDFInfo
- Publication number
- EP0891727A2 EP0891727A2 EP98112532A EP98112532A EP0891727A2 EP 0891727 A2 EP0891727 A2 EP 0891727A2 EP 98112532 A EP98112532 A EP 98112532A EP 98112532 A EP98112532 A EP 98112532A EP 0891727 A2 EP0891727 A2 EP 0891727A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- column
- stem
- cylinder
- aforesaid
- piston
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
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Classifications
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47C—CHAIRS; SOFAS; BEDS
- A47C3/00—Chairs characterised by structural features; Chairs or stools with rotatable or vertically-adjustable seats
- A47C3/20—Chairs or stools with vertically-adjustable seats
- A47C3/30—Chairs or stools with vertically-adjustable seats with vertically-acting fluid cylinder
Definitions
- the present invention relates to a compressed-air column, cushioned and turning, particularly suitable for office chairs.
- this column includes a closed cylinder at one end, and a piston integral with the stem running with lateral seal and coming out with lateral seal and co-axially from the other end of the aforesaid cylinder, the opposed ends of the same cylinder and of the stem being prearranged to be linked to the base and/or to the chair seat.
- a control that can be operated by the user comes out from one end of the stem: this control is linked to a drawer valve placed in the aforesaid piston, which controls the passage of a fluid between two pressure chambers, an upper and a lower one, in the column, corresponding to the opposite faces of the same piston, in order to allow the desired adjustment of the column height by the person sitting down.
- Column of this kind are described, for example, in the European patents EP-0357595 and EP-0462997. Columns of the kind described above are also known: they operate only with air or gas and with a limited pressure, about 6-7 Bar.
- a first aim of the presentinvention is the creation of a compressed-air column, with low pressure, occupying a relatively small space and without the aforesaid disadvantages.
- a further aim of the present invention is the creation of a column with the aforesaid features, which is relatively easy to build, with a low cost and with a high technological reliability.
- the column according to the present invention is substantially characterized by the fact that it includes a cylinder-piston group of the known kind, with the piston integral with the stem end within the cylinder, this end usually pointing with the stem itself upwards and equipped inside with stroke end means which stop the stem extension within such limits that the volume and length of the upper chamber do not fall below the predetermined minimum values, so that these two goals can be achieved: - even when the stem has reached the maximum extension stroke, the upper chamber of the column has such a volume and contains such a quantity of compressed air that the aforesaid cavitation phenomena are avoided; even when the stem has reached the maximum extension stroke, the stem itself is still guided within the cylinder, on one side through the piston and on the other through the upper closing bushing of the cylinder itself, with such a length stretch as to make sure that the whole column maintains the necessary qualities of bending strength.
- the lower end of the cylinder column can be tapered for a length useful for the link with the chair base, or the cylinder may have a constant diameter the whole of its length and can be coated with a skirt of any suitable material, which is tapered in the lower end to be linked to the chair base.
- Figure 1 shows that column C includes a cylindrical body or cylinder 1, made of steel, with a round section, in which a piston 3 is axially moving with lateral seal by means of gasket 2, a piston 3 made, for instance, with a suitable antifriction plastic material and being equipped with an upper axial tang 103 which is inserted with lateral seal by means of gasket 4 and which is fixed with suitable means (see below) to the lower end of a steel tubular stem 5, which runs in a guide bushing 6 made, for instance, of a suitable antifriction plastic material, closing the upper end of the said cylinder 1. At least one suitable seal 7 ensures the sealed link of the bushing 6 to the stem 5 and to the cylinder 1.
- the tang 103 of the piston is axially fixed to the stem 5 by means of an elastic ring 8 placed in a round recess of the tang itself and that snap in a similar round recess provided on the inside lateral surface of the stem.
- the tang 103 can be provided with a ring-shaped recess 9 where a portion of the stem 5 is rimmed by means of a rolling operation, as shown with 205. It is understood that the piston can be fixed to the stem 5 in any other way, also differently from the ones which are here indicated.
- the base 10 is equipped, on its inner side, with a seat where a ring 13, partly projecting, is placed: the ring is made of elastomeric material and it is suitable as a cushion of the lower end stroke of the piston 3.
- the base itself 10 is equipped, in its center, with a threaded through hole 14, with a small groove 15 along the generatrix (see also fig. 4): in the aforesaid threaded hole there is a screw 16 with a seal 116 which seals the said hole and the said groove 15.
- an inflation unit not shown
- the column is provided with opposite conical ends which are introduced into correspondent conical seats in the base and in the seat of the chair itself.
- the stem 5 is provided with a conical end 105 and the cylinder 1 may show as well a lower conical end, which would, however, limit the stroke of the piston 3.
- Figures 1 and 3 show that in the stem 5 there is a control rod which can move axially and which is preferably made of a suitable plastic material.
- the aforesaid rod projects from the upper open end of the stem itself with the section 118, which can be linked to the operating lever or to any other known means connected with the chair seat, and that, with its lower end, operates on a drawer valve placed axially in the piston 3 and in its respective tang 103, said valve being normally closed by means of the air pressure in the lower chamber A of the column and, when pushed down and opened by means of the aforesaid rod 18, connecting said chamber A with the upper chamber B, in order to allow the axial travel of the complex 3-5 and the necessary adjustment in height of the column.
- the drawer valve demands that the complex 3, 103 is axially equipped with a hole divided into three portions with downward increasing diameter, as indicated with 19, 20 and 21.
- the central hole portion 20 the following elements are introduced: an O-ring 22, a bushing 23 made of plastic material, whose inside diameter is substantially the same as that of the hole 19, and then a second O-ring 24, and the whole is blocked on the place by means of a metal washer 25 which, through its outward rim profiled against unthreading, is forced by pressure into the hole portion 21, until it reaches the bottom of the hole.
- the inside diameter of the washer 25 is substantially the same as - or only slightly bigger than - the diameter of the aforesaid hole portion.
- the inside diameter of the O-rings 22 and 24 is appropriately smaller than diameter of the same hole portion 19.
- the bushing 23 is outwardly equipped with a central ring-shaped recess which forms, with the hole portion 20, a ring-shaped chamber 26, which is constantly connected with the upper chamber B of the column by means of at least one suitable hole 27, radially positioned on a base bulge of the tang 103 of the piston 3.
- some holes 28 are also open: they are provided on the bushing 23, which can be introduced into its seat in any direction.
- the hole portion 19 and the assembly 22-25 are crossed by a cylindrical drawer 29, preferably made of steel, which can move axially and cooperates with lateral seal with the O-rings 22, 24, a portion of it projecting into the axial cavity of the stem 5, at atmospheric pressure, while the other end is in the pressure chamber A of the column, and which is, provided with a head 30, for instance adjoined, which usually leans against the washer 25.
- the pressure in the chamber A in fact, normally keeps the drawer 29 pushed upwards. In such a condition, as shown in figure 1, the portion of the drawer 29 which projects from the top of the tang 103 of the piston 3, keeps the control rod lifted and appropriately projecting from the stem 5.
- the drawer 29 is provided with a central ring-shaped recess 31 which, when the drawer itself is at rest, is positioned between the O-rings 22 and 24, preventing the communication between the chambers A and B, since the O-ring 24 is in sealing contact with the drawer itself.
- the rod pushes down the drawer 29 and brings the ring-shaped recess 31 across the O-ring 24, which does not play its sealing role anymore.
- the chambers A and B of the column communicate in this case by means of the hole 28, the chamber 26 and the hole 27, as well shown in figure 3.
- the main feature of the column according to the present invention is the fact that in the column itself means are provided which stop the piston 3 stroke in the phase of extension of stem 5 to such an extent that the stem itself is still guided within the cylinder 1, with so long a portion, for example, as 1/3 of the length of the stem itself or, anyway, with such a length that the whole telescopic system keeps its features of bending strength which are necessary for the use to which it is bound.
- the chamber B of the column should keep such a predetermined minimum volume as to avoid those cavitation phenomena which can be observed in the columns of the known type.
- a spacing bushing 32 is introduced, made for instance of a suitable plastic material, equipped on its lower end with a rim 132, thickened and shaped to house a ring 33 made of a suitable elastomeric material, which can be useful as a damper for the upper end stroke of the piston 3.
- the upper end of the bushing 32 leans onto a metal washer 34, which is kept at a distance from the gasket 7 by means of an elastic ring 35, fitted into an appropriate ring-shaped recess 36, which has been obtained from the inside lateral surface of the cylinder.
- the bushing 32 has such an outside diameter that it must be fitted into the cylinder 1 by means of a light forcing, so as to remain in its high position.
- the bushing 32 will be equipped, at least on its lower end, with appropriate radial holes, similarly to bushing 23 of the drawer valve placed on the piston 3.
- the elastic ring 35 other means can be used, such as a ring-shaped ledge towards the inside of the cylinder 1, which should be carried out with an outward rolling of the cylinder itself.
Landscapes
- Chairs Characterized By Structure (AREA)
- Nozzles (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT97BO000435A IT1293250B1 (it) | 1997-07-17 | 1997-07-17 | Colonna ad aria compressa, ammortizzata e girevole, particolarmente per sedie da ufficio. |
ITBO970435 | 1997-07-17 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0891727A2 true EP0891727A2 (de) | 1999-01-20 |
EP0891727A3 EP0891727A3 (de) | 1999-11-10 |
Family
ID=11342409
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP98112532A Withdrawn EP0891727A3 (de) | 1997-07-17 | 1998-07-07 | Gasdruckfeder, insbesondere für Bürostühle |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0891727A3 (de) |
IT (1) | IT1293250B1 (de) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006058272A2 (en) * | 2004-11-24 | 2006-06-01 | Humanscale Corporation | Delayed gas spring chair |
EP3001932A1 (de) * | 2014-09-30 | 2016-04-06 | Innotec Motion GmbH | Vorrichtung zur höhenverstellung einer sitzfläche eines sitzmöbels |
WO2016050286A1 (de) * | 2014-09-30 | 2016-04-07 | Innotec Motion GmbH | Vorrichtung zur höhenverstellung einer sitzfläche eines sitzmöbels |
CN113123042A (zh) * | 2021-03-05 | 2021-07-16 | 李海宁 | 一种新型纺织用染色装置 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0357595A1 (de) | 1985-12-20 | 1990-03-14 | Eberspaecher J | Abgasreinigungsvorrichtung für dieselmotoren. |
EP0462997A1 (de) | 1989-03-13 | 1992-01-02 | Lifter Srl | Hydropneumatische vorrichtung zum höhenverstellen von stühlen. |
IT1262248B (it) | 1993-12-10 | 1996-06-19 | Lifter Srl | Colonna ammortizzata girevole per sedia da ufficio |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2907100A1 (de) * | 1979-02-23 | 1980-08-28 | Bauer Fritz & Soehne Ohg | Laengenverstellbare gasfeder |
DE4009100A1 (de) * | 1990-03-21 | 1991-09-26 | Stabilus Gmbh | Stufenlos blockierbares hubaggregat |
US5211379A (en) * | 1991-12-18 | 1993-05-18 | P. L. Porter Company | Continuously self-compensating hydraulic positioner |
US5516082A (en) * | 1993-06-25 | 1996-05-14 | Talleres Gain, S. Coop. S.L. | Gas cylinder |
DE9315245U1 (de) * | 1993-10-09 | 1994-01-05 | Suspa Compart Ag, 90518 Altdorf | Längenverstellbare Gasfeder |
DE4426846A1 (de) * | 1994-07-28 | 1994-12-15 | Suspa Compart Ag | Längenverstellbare Gasfeder für Stühle, Tische o. dgl. |
-
1997
- 1997-07-17 IT IT97BO000435A patent/IT1293250B1/it active IP Right Grant
-
1998
- 1998-07-07 EP EP98112532A patent/EP0891727A3/de not_active Withdrawn
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0357595A1 (de) | 1985-12-20 | 1990-03-14 | Eberspaecher J | Abgasreinigungsvorrichtung für dieselmotoren. |
EP0462997A1 (de) | 1989-03-13 | 1992-01-02 | Lifter Srl | Hydropneumatische vorrichtung zum höhenverstellen von stühlen. |
IT1262248B (it) | 1993-12-10 | 1996-06-19 | Lifter Srl | Colonna ammortizzata girevole per sedia da ufficio |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2006058272A2 (en) * | 2004-11-24 | 2006-06-01 | Humanscale Corporation | Delayed gas spring chair |
WO2006058272A3 (en) * | 2004-11-24 | 2007-08-16 | Humanscale Corp | Delayed gas spring chair |
US7673941B2 (en) | 2004-11-24 | 2010-03-09 | Humanscale Corporation | Delayed gas spring chair |
EP3001932A1 (de) * | 2014-09-30 | 2016-04-06 | Innotec Motion GmbH | Vorrichtung zur höhenverstellung einer sitzfläche eines sitzmöbels |
WO2016050286A1 (de) * | 2014-09-30 | 2016-04-07 | Innotec Motion GmbH | Vorrichtung zur höhenverstellung einer sitzfläche eines sitzmöbels |
CN113123042A (zh) * | 2021-03-05 | 2021-07-16 | 李海宁 | 一种新型纺织用染色装置 |
CN113123042B (zh) * | 2021-03-05 | 2022-12-23 | 江西江顺纺织有限公司 | 一种新型纺织用染色装置 |
Also Published As
Publication number | Publication date |
---|---|
EP0891727A3 (de) | 1999-11-10 |
ITBO970435A0 (it) | 1997-07-17 |
ITBO970435A1 (it) | 1999-01-17 |
IT1293250B1 (it) | 1999-02-16 |
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