US3633964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for adjusting the slope of a chair back
Assignee: Individual
•
Filing: 1970-02-10
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Granted: 1972-01-11
•
Expires: 1990-02-10
Abstract
Abstract The device comprises a hollow casing, supported by the seat frame of a chair and delimiting two opposed truncated bearings on which are applied, by the action of at least one resilient recoil member, two truncated cones, also opposed, loosely screwed on to a large pitch helicoidal grooved common rod, an operating member controlling, against the action of the resilient member, the simultaneous loosening of the truncated cones in relation to the truncated bearings.
Inventors
- 👤 Jean-Claude Andre Bertin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:56
CPC Classifications
A; A47; A47C; A47C1/00; A47C1/02; A47C1/022; A47C1/024; A47C1/027; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20576; Y10T74/20636; Y10T74/2066
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
195 words
A chair back adjusting mechanism comprising a casing defining a first pair of spaced brake elements, a rod moveably mounted in and extending through said casing and said brake elements, a second pair of brake elements moveably mounted on said rod within said casing, spring means in said casing normally urging said second pair of brake elements respectively into braking engagement with said first pair of brake elements, means between said rod and said second pair of brake elements to retain said rod against movement when said first and second pairs of brake elements are in braking engagement, and control means in said casing for engaging the facing portions of said second pair of brake elements to move said elements in opposition to said spring means to disengage said second brake elements from said first brake elements and permit adjustment of the mechanism, said control means including an operating member externally of said casing, said first pair of brake elements comprise truncated conical brake drums, said second pair of brake elements comprise truncated brake shoes, and said rod retaining means comprises interengaging threads on said shoes and rod, said rod extending axially through said shoes.
Claim 2
Dependent Claim
195 words
A chair back adjusting mechanism comprising a casing defining a first pair of spaced brake elements, a rod moveably mounted in and extending through said casing and said brake elements, a second pair of brake elements moveably mounted on said rod within said casing, spring means in said casing normally urging said second pair of brake elements respectively into braking engagement with said first pair of brake elements, means between said rod and said second pair of brake elements to retain said rod against movement when said first and second pairs of brake elements are in braking engagement, and control means in said casing for engaging the facing portions of said second pair of brake elements to move said elements in opposition to said spring means to disengage said second brake elements from said first brake elements and permit adjustment of the mechanism, said control means including an operating member externally of said casing, said first pair of brake elements comprise truncated conical brake drums, said second pair of brake elements comprise truncated brake shoes, and said rod retaining means comprises interengaging threads on said shoes and rod, said rod extending axially through said shoes.
Claim 3
Dependent Claim
72 words
A mechanism according to claim 1, wherein said drums are in the end portions of said casing with their large bases in facing relation, said shoes each having a grooved collar extending from its large base portion, and said control means comprising a yoke pivotally mounted in said casing on an axis perpendicular to said rod, said yoke having cam means on its arms respectively engaged in the grooves of said collars.
Claim 4
Dependent Claim
89 words
A mechanism according to claim 1, wherein said drums are in the intermediate portion of said casing with their smaller ends in adjoining relation and defining a through opening for said rod, the smaller ends of said shoes being in facing relation and being urged toward each other by said spring means which are in the end portions of said casing, and said control means comprising a cam pivotally mounted in said through opening for engagement with said shoes to move the latter out of engagement with said drums.
Claim 5
Dependent Claim
45 words
A mechanism according to claim 1, in combination with a chair comprising a seat frame and a back frame pivotally mounted on said seat frame, said casing being mounted on said seat frame and one end of said rod being connected to said back frame.
References Cited (Backward Citations)
BE528038A
Cited
US2252097A
Cited
US2750994A
Cited
US2928621A
Cited
US3048416A
Cited
FR1449684A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |