US4157203A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Articulated double back for chairs
Assignee: Center for Design Research and Development NV
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Filing: 1978-05-01
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Granted: 1979-06-05
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Expires: 1998-05-01
Abstract
Abstract A back for a chair comprises at least one back-supporting frame member, a lower back mounted on the frame member for backward tilting movement about a first horizontal, transverse axis and yieldably restrained against such backward tilting and an upper back mounted on the lower back for tilting movement relative to and independently of the lower back about a second horizontal, transverse axis spaced a substantial distance above the first axis and yieldably restrained against such backward tilting. The axis about which the lower back tilts is located a substantial distance above the seat at a location corresponding to about the middle of the back of an adult human sitting in the chair.
Inventors
- 👤 Emilio Ambasz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:10
CPC Classifications
A; A47; A47C; A47C7/00; A47C7/36; A47C7/40; A47C7/44; A47C7/448; A47C7/441; A47C7/443; A47C7/46
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
187 words
A chair back comprising at least one back-supporting frame member, a lower back, means mounting the lower back on the frame member for backward tilting movement about a first horizontal, transverse axis and for yieldably restraining such backward tilting, the first axis being located substantially above the seat at a location corresponding to about the middle of the anatomical back of an adult human sitting in the chair, an upper back, and means mounting the upper back on the lower back for backward tilting movement of the upper back relative to and independently of the lower back about a second horizontal, transverse axis located substantially above the first horizontal axis and for yieldably restraining such backward tilting, the lower back being vertically and transversely co-extensive with the major portion of the middle part of the anatomical back of an adult human, and the upper back being verticallly and transversely co-extensive with the major portion of the upper part of the anatomical back of an adult human in the region where the spine curves forward when such human is sitting upright and straightens when such human arches backward.
Claim 2
Dependent Claim
187 words
A chair back comprising at least one back-supporting frame member, a lower back, means mounting the lower back on the frame member for backward tilting movement about a first horizontal, transverse axis and for yieldably restraining such backward tilting, the first axis being located substantially above the seat at a location corresponding to about the middle of the anatomical back of an adult human sitting in the chair, an upper back, and means mounting the upper back on the lower back for backward tilting movement of the upper back relative to and independently of the lower back about a second horizontal, transverse axis located substantially above the first horizontal axis and for yieldably restraining such backward tilting, the lower back being vertically and transversely co-extensive with the major portion of the middle part of the anatomical back of an adult human, and the upper back being verticallly and transversely co-extensive with the major portion of the upper part of the anatomical back of an adult human in the region where the spine curves forward when such human is sitting upright and straightens when such human arches backward.
Claim 3
Dependent Claim
45 words
A chair according to claim 1, wherein the means mounting the lower back and the means mounting the upper back include substantially identical articulating resilient coupling assemblies, each of which assemblies has an upper part and a lower part connected to each other for articulation.
Claim 4
Dependent Claim
41 words
A chair according to claim 2, wherein the frame member includes a hollow upper portion receiving telescopically the lower member of a coupling assembly and the lower back has a downwardly opening socket receiving the upper member of the coupling assembly.
Claim 5
Dependent Claim
40 words
A chair according to claim 2, wherein the lower back has an upwardly open socket receiving the lower end of a coupling assembly and the upper back has a downwardly open socket receiving the upper end of the coupling assembly.
Claim 6
Dependent Claim
36 words
A chair according to claim 4, wherein the sockets on the lower and upper backs are spaced apart and wherein the parts of the coupling assembly between the sockets are enclosed within a flexible, extensible tube.
Claim 7
Dependent Claim
58 words
A chair according to claim 2, wherein each coupling assembly includes means establishing and maintaining a given position of the upper part relative to the lower part in the absence of application of a predetermined force to the upper part and for yielding to a force imposed on the upper part that is greater than such predetermined force.
Claim 8
Dependent Claim
43 words
A chair according to claim 1, wherein there is a back-supporting frame member located adjacent each side of the chair and wherein the means mounting the lower back on the frame member includes a resilient articulating coupling assembly associated with each frame member.
Claim 9
Dependent Claim
30 words
A chair according to claim 7, wherein the means mounting the upper back on the lower back includes a resilient articulating coupling assembly adjacent each side of the chair back.
Claim 10
Dependent Claim
76 words
A chair according to claim 1, wherein the profiles of the upper edge of the lower back and the lower edge of the upper back are substantially complementary and the front surfaces of the upper and lower backs intersect at an angle with the front surface of the upper back being more upright than the front surface of the lower back when the upper back is in its upright, restrained position relative to the lower back.
Claim 11
Dependent Claim
22 words
A chair according to claim 1, wherein in its restrained position the upper back is inclined forwardly relative to the lower back.
Claim 12
Dependent Claim
48 words
A chair according to claim 1, wherein the means mounting the lower back on the frame member includes means affording vertical movement of the lower back relative to the back-supporting frame member and for releasably locking the lower back in a selected position relative to the frame member.
Claim 13
Dependent Claim
52 words
A chair according to claim 1, wherein the means mounting the lower back on the frame member includes first stop means engageable to establish the restrained position of the lower back and second stop means engageable to limit the extent of backward tilting movement of the lower back about the first axis.
Claim 14
Dependent Claim
52 words
A chair according to claim 1, wherein the means mounting the upper back on the lower back includes first stop means engageable to establish the restrained position of the upper back and second stop means engageable to limit the extent of backward tilting movement of the upper back about the second axis.
Claim 15
Dependent Claim
20 words
A chair according to claim 1, wherein the back-supporting frame member is located in generally the center of the chair.
Claim 16
Dependent Claim
65 words
A chair according to claim 1, wherein the means mounting the lower back on the frame member includes a resilient articulating coupling assembly having an upper part and a lower part joined for articulation, means establishing and resiliently maintaining a given position of the upper part relative to the lower part, and stop means for limiting the extent of rearward tilting of the lower back.
Claim 17
Dependent Claim
104 words
A chair according to claim 1, wherein the means mounting the lower back on the frame member includes a resilient articulating coupling assembly having a lower part joined to the frame member, an upper part joined to the lower back, an axle joining the upper and lower parts for pivoting about the axis, a spring reaction plate mounting on the axle, the plate and the two parts having spaced-apart surfaces facing each other, and a compression spring positioned between the facing surface of each part and the corresponding facing surface of the reaction plate and yieldably restraining the lower back in the upright position.
Claim 18
Dependent Claim
35 words
A chair according to claim 16, wherein the parts and the reaction plate include first stop portions adapted to engage and hold the parts in a position establishing the upright position of the lower back.
Claim 19
Dependent Claim
32 words
A chair according to claim 17, wherein the parts and the reaction plate include second stop portions adapted to engage in a selected limit position of backward tilting of the lower back.
Claim 20
Dependent Claim
31 words
A chair according to claim 18 wherein the means mounting the upper back on the lower back is substantially identical to the means mounting the lower back on the frame member.
Claim 21
Dependent Claim
108 words
In a chair having a back mounted on a back-supporting member to tilt backward from a restrained relatively upright position, an improved resilient articulating coupling assembly comprising a first part joined to the back-supporting member, a second part joined to the back, an axle joining the two parts for pivotal movement relative to each other, a spring reaction plate mounted on the axle, each of the parts and the reaction plate having spaced-apart surfaces facing each other, and a compression spring engaged between the facing surface of each part and the corresponding facing surface of the reaction plate and yieldably restraining the back in a generally upright position.
Claim 22
Dependent Claim
108 words
In a chair having a back mounted on a back-supporting member to tilt backward from a restrained relatively upright position, an improved resilient articulating coupling assembly comprising a first part joined to the back-supporting member, a second part joined to the back, an axle joining the two parts for pivotal movement relative to each other, a spring reaction plate mounted on the axle, each of the parts and the reaction plate having spaced-apart surfaces facing each other, and a compression spring engaged between the facing surface of each part and the corresponding facing surface of the reaction plate and yieldably restraining the back in a generally upright position.
Claim 23
Dependent Claim
36 words
The improvement claimed in claim 20, wherein the parts and the reaction plate include first stop portions adapted to engage each other and hold the parts in a position establishing the upright position of the back.
Claim 24
Dependent Claim
31 words
The improvement according to claim 20, wherein the parts and the reaction plate include second stop portions adapted to engage in a selected limit position of backward tilting of the back.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-06-04 | 1982-12-04 | 1983-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-04 | 1986-12-04 | 1987-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-04 | 1990-12-04 | 1991-06-05 | $7700.00 | Window Closed / Lapsed |