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Patent US3601444A successfully refreshed from Google Patents.
US3601444A
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Chair control with support for the torsion spring
Assignee: Doerner Products Co Ltd
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Filing: 1969-11-25
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Granted: 1971-08-24
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Expires: 1989-11-25
Abstract
Abstract A chair control for tilting chairs and posture chairs having a coiled torsion spring oriented in a horizontal plane with its axis parallel to the pivots on which the control tilts. The chair control has two frames which are pivotally connected to permit relative pivotal movement, one of the frame members being mountable on the top end of the chair post which is carried by the chair base. The torsion spring is supported by a fixed frame of the chair control so that it is fully supported thereby both when at rest and when subjected to torsional stresses induced by a person sitting in the chair when such person leans back in the chair.
Inventors
- 👤 Joseph T Doerner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:10
CPC Classifications
A; A47; A47C; A47C1/00; A47C1/02; A47C1/022; A47C1/024; A47C1/027; A47C7/00; A47C7/36; A47C7/40; A47C7/44; A47C7/441; A47C7/443; A47C7/444
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
122 words
A chair control having: a. a first nontiltable frame mountable on a chair base; b. a second tiltable frame member; c. a helical torsion spring operatively connected to the frame members to resist relative movement of the frame members in one direction; d. a hinge pin pivotally connecting the frame members together for relative pivotal movement, said pin extending axially through the torsion spring; and e. a spring support pad mounted on the first frame underneath the torsion spring, said pad having its upper surface concaved to receive therein adjacent portions of the spring in free slidable relationship whereby the forces generated by the torsionally loaded spring are carried solely on said support member and the spring is restrained against eccentric displacement.
Claim 2
Dependent Claim
122 words
A chair control having: a. a first nontiltable frame mountable on a chair base; b. a second tiltable frame member; c. a helical torsion spring operatively connected to the frame members to resist relative movement of the frame members in one direction; d. a hinge pin pivotally connecting the frame members together for relative pivotal movement, said pin extending axially through the torsion spring; and e. a spring support pad mounted on the first frame underneath the torsion spring, said pad having its upper surface concaved to receive therein adjacent portions of the spring in free slidable relationship whereby the forces generated by the torsionally loaded spring are carried solely on said support member and the spring is restrained against eccentric displacement.
Claim 3
Dependent Claim
52 words
The invention according to claim 1 in which the torsion spring comprises a pair of oppositely wound coils connected together by a rearwardly extending connecting portion and the spring support pad being divided into two spaced-apart sections forming a passageway through which connecting portion extends, each section supporting one of said coils.
References Cited (Backward Citations)
US2202630A
Cited
US3339973A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |