US3877751A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Split back dental chair apparatus
Assignee: HEK Manufacturing Co Inc
•
Filing: 1973-07-30
•
Granted: 1975-04-15
•
Expires: 1993-07-30
Abstract
Abstract A dental chair conversion apparatus capable of use as a loungetype chair and having an adjustable head rest mounted on an elongated plate with a rack formed thereon and with the plate and rack slidable in a bracket which is mounted in the keyway of a conventional back support of the dental chair and fixedly held there by a screw. A latch having a projection is pin mounted through ears on the bracket and spring biased to permit manual operation of the latch to selectively engage the rack in ratchet fashion, to permit manual adjustment of the height of the head rest.
Inventors
- 👤 Keith O Rasmussen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:00
CPC Classifications
A; A47; A47C; A47C7/00; A47C7/36; A47C7/38; A61; A61G; A61G15/00; A61G15/10; A61G15/12; A61G15/125
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
152 words
A thin profile split back conversion for a dental chair having a frame including a tiltable back support member formed with a keyway for slidably supporting a backrest and an articulated headrest, said conversion comprising a bracket formed for slidable mounting in the keyway of the back support member and having a second keyway formed therein; Means for adjustably securing said bracket in said first named keyway; a thin profile backrest secured to said bracket; a thin profile headrest having an elongated tongue slidable in said second keyway and formed with a series of ratchet teeth therealong; a pawl pivotally mounted on said bracket medially thereof in underlying relation to said backrest and formed for selective engagement with said ratchet teeth; spring means urging said pawl against said teeth; and a handle secured to said pawl and extending laterally from said bracket for selective manual engagement and manipulation to disengage said pawl.
Claim 2
Dependent Claim
152 words
A thin profile split back conversion for a dental chair having a frame including a tiltable back support member formed with a keyway for slidably supporting a backrest and an articulated headrest, said conversion comprising a bracket formed for slidable mounting in the keyway of the back support member and having a second keyway formed therein; Means for adjustably securing said bracket in said first named keyway; a thin profile backrest secured to said bracket; a thin profile headrest having an elongated tongue slidable in said second keyway and formed with a series of ratchet teeth therealong; a pawl pivotally mounted on said bracket medially thereof in underlying relation to said backrest and formed for selective engagement with said ratchet teeth; spring means urging said pawl against said teeth; and a handle secured to said pawl and extending laterally from said bracket for selective manual engagement and manipulation to disengage said pawl.
Claim 3
Dependent Claim
42 words
A thin profile split back conversion as described in claim 1 and wherein said bracket is of substantially U-shaped cross section opening toward said backrest, and mounting ears are formed at the corners of said bracket for rigidly securing to said backrest.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |