EP0034068A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Height adjustment device for furniture and a chair incorporating the device
Assignee: Steelcase Inc
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Filing: 1981-02-11
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Granted: —
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Expires: 2001-02-11
Abstract
Abstract A height adjustment device for furniture, such as chairs, comprises a pair of telescoping tubular members (3, 4) which, in a chair interconnect the base portion (5) and the seat portion (6) of the chair and form a supportive pedestal therefor. A ram (7) is mounted in the tubular members, such that extension and retraction of the ram respectively raises and lowers the chair seat. The ram and tubular members are sized in a manner to form an annular space therebetween which permits the ram to assume an eccentric position in the tubular members during a loaded chair condition. The ram ends are pivotally connected in the tubular members (27a, 29; 32, 43), such that lateral forces (as distinguished from vertical forces) which are applied to a chair seat are supported primarily by the tubular members, and are not transmitted to the ram.
Inventors
- 👤 Duane Milo Beukema
- 👤 Jack Richard Knoblauch
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 02:34
CPC Classifications
A; A47; A47C; A47C3/00; A47C3/20; A47C3/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
193 words
A height adjustment device for an item of furniture, comprising a pair of telescoping tubular members (3, 4) for interconnecting upper and lower portions of the item of furniture, and a ram (7) mounted within the tubular members and having a lower end thereof connected with one of the tubular members, and an upper end thereof connected with the other of the tubular members, whereby extension and retraction of the ram respectively raises and lowers the upper portion with respect to the lower, the ram normally assuming a substantially concentric relationship with the tubular members during a nonloaded condition, characterised in that the ram and the tubular members are mutually sized in a radial direction to form a space therebetween for permitting the ram to assume an eccentric relationship with the tubular members during a loaded condition, and there are means (27a, 29; 32, 43) for permitting the upper and lower ram ends to pivot with respect to the associated tubular members in which they are connected, whereby lateral forces which are applied to the upper portion during use are supported wholly by the tubular members, end are not transmitted to the ram.
Claim 2
Dependent Claim
193 words
A height adjustment device for an item of furniture, comprising a pair of telescoping tubular members (3, 4) for interconnecting upper and lower portions of the item of furniture, and a ram (7) mounted within the tubular members and having a lower end thereof connected with one of the tubular members, and an upper end thereof connected with the other of the tubular members, whereby extension and retraction of the ram respectively raises and lowers the upper portion with respect to the lower, the ram normally assuming a substantially concentric relationship with the tubular members during a nonloaded condition, characterised in that the ram and the tubular members are mutually sized in a radial direction to form a space therebetween for permitting the ram to assume an eccentric relationship with the tubular members during a loaded condition, and there are means (27a, 29; 32, 43) for permitting the upper and lower ram ends to pivot with respect to the associated tubular members in which they are connected, whereby lateral forces which are applied to the upper portion during use are supported wholly by the tubular members, end are not transmitted to the ram.
Claim 3
Dependent Claim
17 words
A height adjustment device as claimed in Claim 1 in which the ram comprises a pneumatic cylinder.
Claim 4
Dependent Claim
110 words
A height adjustment device as claimed in Claim 1 or Claim 2 which includes: means (27a, 29) for rotatably mounting the lower end of the ram relative to the tubular members; a mounting bracket (14) shaped for fixed connection with a lower surface of a load-receiving platform (6) and including a noncircularly shaped socket (33) therein; and a stud (32) extending upwardly and axially from the ram upper end, and including a noncircularly shaped portion mating with and telescopingly received in the socket of the mounting bracket, whereby rotation of the platform is positively transmitted to the ram to rotate the ram about the said one of the tubular members.
Claim 5
Dependent Claim
53 words
A height adjustment device as claimed in Claim 3 in which the socket includes an arcuately shaped upper surface (48) which abuttingly mates with an arcuately shaped free end (49) of the stud to form an articulating joint portion of the pivot means for eliminating the transmission of lateral forces to the ram.
Claim 6
Dependent Claim
151 words
A height adjustment device as claimed in Claim 1 or Claim 2 which includes a mounting bracket (14) for connection with a lower surface of a load-receiving platform (6), a stud (32) extending upwardly and axially from the ram upper end and including a pin (41) received in a mating aperture in the mounting bracket, and in which the pivot means includes: an annularly shaped space disposed between the ram pin and the mounting member aperture for permitting the mounting member to assume an eccentric relationship with the ram pin; an arcuately shaped terminal surface (49) on the upper end of the ram stud supporting the seat mounting member thereon; and an arcuately shaped surface (48) on the mounting member mating with and abutting the said ram terminal surface, thereby permitting slight pivoting between said platform and the ram for avoiding the application of nonlongi- tudinally oriented forces to the ram.
Claim 7
Dependent Claim
32 words
A height adjustment device as claimed in Claim 5 in which the mounting member has a separate insert portion (43) disposed adjacent the stud and includes the said arcuate surface (48) thereon.
Claim 8
Dependent Claim
28 words
A height adjustment device as claimed in Claim 6 in which the insert is constructed of a synthetic resin material for antifriction abutment with the said stud surface.
Claim 9
Dependent Claim
48 words
A height adjustment device as claimed in Claim 6 or Claim 7 in which the insert has a socket shaped body into which the stud is received, the stud and insert being sized to form a space (47) therebetween for permitting pivoting between the said abutting arcuate surfaces.
Claim 10
Dependent Claim
48 words
A height adjustment device as claimed in Claim 8 in which the insert socket and the stud have hexagonal lateral-cross-sections and are sized to form a space therebetween sufficient to permit pivoting between said abutting arcuate surfaces, yet positively to transmit rotation of the platform to said ram.
Claim 11
Dependent Claim
30 words
A chair which comprises in combination a base portion, a seat portion and, connecting the two portions, a height adjustment device as claimed in any one of the preceding claims.
References Cited (Backward Citations)
No citation records indexed.
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