Patent US4397656A successfully refreshed from Google Patents.
Patent EP0032839A2 successfully refreshed from Google Patents.
EP0032839A2
Expired / Lapsed
EP
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Chair shells
Assignee: Individual
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Filing: 1981-01-20
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Granted: —
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Expires: 2001-01-20
Abstract
Abstract A chair shell of resilient material such as polypropylene comprises a back support 12 and a seat portion 14. The natural deformability of the back support 12 is modified by slits 22, 24 and holes 32, 34, 36 so that under pressure from the back of a sitter resting against the back support the support is resiliently deformed into a shape which, in vertical section, includes a convex curve positioned properly to support the sitter's spine in the lumbo-sacral region and which is horizontal in convex section. The deformability of seat 14 is modified by slits 42, 44 and holes 42,46,48,50,54 to provide softer rear and front zones 44 and 52 to reduce the pressure on the ischial tuberosities and lower thighs of the sitter. The chair shell provides comfortable and orthopaedically desirable support whilst avoiding the need for thick upholstery. The undeformed state of the chair shell may be designed to allow the chairs to be easily stacked.
Inventors
- 👤 Bernard Curtis Watkin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 14:40
CPC Classifications
A; A47; A47C; A47C7/00; A47C7/02; A47C7/024; A47C3/00; A47C3/12; A47C7/029; A47C7/36; A47C7/40; A47C7/405; A47C7/46; Y; Y10; Y10S; Y10S297/00; Y10S297/02
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
78 words
A chair shell of resilient material comprising a back support and a seat portion in which the deformability of the back support is locally modified so that under pressure from the back of a sitter resting against the back support the back support is resiliently deformed into a shape which, in vertical section, includes a convex curve positioned to support the sitter's spine in a convex curve in the lumbo-sacral region and which is concave in horizontal section.
Claim 2
Dependent Claim
78 words
A chair shell of resilient material comprising a back support and a seat portion in which the deformability of the back support is locally modified so that under pressure from the back of a sitter resting against the back support the back support is resiliently deformed into a shape which, in vertical section, includes a convex curve positioned to support the sitter's spine in a convex curve in the lumbo-sacral region and which is concave in horizontal section.
Claim 3
Dependent Claim
31 words
A chair shell as claimed in claim 1, in which the deformability of the back support is locally modified by providing zones of weakness in the material of the back support.
Claim 4
Dependent Claim
50 words
A chair shell as claimed in claim 2, in which an opening is formed in the chair shell at the junction of the back support and seat portion and the back support has a lower portion immediately above the opening which is deformed backwardly under pressure of the sitter's back.
Claim 5
Dependent Claim
30 words
A chair shell as claimed in claim 3, in which the lower portion of the back support is formed with a centrally disposed slit extending upwardly from the said opening.
Claim 6
Dependent Claim
42 words
A chair shell as claimed in claim 4, in which the lower portion of the back support is formed with slits extending upwardly from the said opening and.positioned on either side of the central slit near the sides of the back support.
Claim 7
Dependent Claim
43 words
A chair shell as claimed in claim 5 or claim 6, in which a line of weakness is formed in the back support which extends horizontally across the back support in the region of the upper ends of the said slit or slits.
Claim 8
Dependent Claim
64 words
A chair shell as claimed in any one of claims 3 to 6, in which the upper portion of the back support is formed with lines of weakness arranged so that pressure of the sitter's back causes the top of the back support to move backwards to increase the convexity in horizontal section of the back support whilst increasing its concavity in horizontal section.
Claim 9
Dependent Claim
49 words
A chair shell as claimed in claim 7, in which the upper portion of the back support is formed with two lines of weakness extending from a point near the centre of the back support to points near the upper right and left corner's respectively of the back support.
Claim 10
Dependent Claim
69 words
A chair shell as claimed in any preceding claim, - in which the back support in its undeformed state has a shape which is convex in vertical section and ,concave in horizontal section and the deformability of the back support is locally modified so that under pressure from the back of a sitter the back support is resiliently deformed so as to increase the said convexity and concavity respectively.
Claim 11
Dependent Claim
35 words
A chair shell as claimed in any preceding claim, in which the seat portion is formed with a rear portion adapted to be deformed resiliently downwards under pressure from the ischial tuberosities of a sitter.
Claim 12
Dependent Claim
25 words
A chair shell as claimed in claim 10, in which the seat portion is formed with two independently deformable rear portions positioned side by side.
Claim 13
Dependent Claim
32 words
A chair shell as claimed in claim 10, in which the seat portion has a front portion adapted to be resiliently deformed downwards under pressure from the front under-thighs of a sitter.
Claim 14
Dependent Claim
32 words
A chair shell as claimed in any preceding claim, in which the deformability of the back support is modified by lines of weakness including lines of holes formed in the back support.
Claim 15
Dependent Claim
22 words
A chair shell as claimed in any preceding claim, in which the material of the chair shell is a crystalline propylene polymer.
Claim 16
Dependent Claim
27 words
A chair shell as claimed in claim 14, in which the material is a homopolymer or copolymer of propylene with up to 18% by weight of ethylene.
Claim 17
Dependent Claim
17 words
A chair comprising a chair shell as claimed in any preceding claim fixed to a supporting frame.
References Cited (Backward Citations)
No citation records indexed.
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