US3823979A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dental chair
Assignee: DEN-TAL-EZ DENTAL PRODUCTS CORP A CORP OF PA
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Filing: 1973-01-11
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Granted: 1974-07-16
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Expires: 1993-01-11
Abstract
Abstract A dental chair comprising a seat portion having a back portion pivotally secured thereto. A lever element is secured at its upper end to the lower center portion of the back portion and is pivotally secured at its lower end to the rearward end of a clevis element. The lever element is pivotally secured, above its lower end, to the seat portion. The forward end of the clevis element is secured to a sleeve which is threaded onto the screw shaft of an electric motor for longitudinal movement thereon. Movement of the sleeve by the screw shaft causes the clevis element to act upon the lower end of the lever element thereby causing the lever element and the back portion to pivot about the pivotal connection of the lever element and the seat portion.
Inventors
- 👤 R Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:14
CPC Classifications
A; A61; A61G; A61G15/00; A61G15/02; A47; A47C; A47C1/00; A47C1/02; A47C1/022; A47C1/024; A47C1/0242; A61G2203/00; A61G2203/70; A61G2203/72; A61G2203/726
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
191 words
A dental chair comprising, a seat portion comprising a frame means and having rearward and forward end, a back portion having upper and lower ends, an electric motor secured to said frame means having a rearwardly extending screw shaft, a member threadably mounted on said screw shaft for longitudinal movement thereon, a clevis element having rearward and forward ends said clevis element having a first pair of spaced apart arms at its forward end secured to said member, and a second pair of spaced apart arms at its rearward end, a lever element having upper and lower ends, the upper end of said lever element being secured to said back portion, the lower end of said lever element being pivotally secured to the spaced apart arms of the rearward end of said clevis element, and means pivotally connecting said lever element above its said lower end to said frame means whereby activation of said motor will cause the rearward end of said clevis element to act upon the lower end of said lever element to pivot said back portion about the pivotal connection between said lever element and said frame means.
Claim 2
Dependent Claim
191 words
A dental chair comprising, a seat portion comprising a frame means and having rearward and forward end, a back portion having upper and lower ends, an electric motor secured to said frame means having a rearwardly extending screw shaft, a member threadably mounted on said screw shaft for longitudinal movement thereon, a clevis element having rearward and forward ends said clevis element having a first pair of spaced apart arms at its forward end secured to said member, and a second pair of spaced apart arms at its rearward end, a lever element having upper and lower ends, the upper end of said lever element being secured to said back portion, the lower end of said lever element being pivotally secured to the spaced apart arms of the rearward end of said clevis element, and means pivotally connecting said lever element above its said lower end to said frame means whereby activation of said motor will cause the rearward end of said clevis element to act upon the lower end of said lever element to pivot said back portion about the pivotal connection between said lever element and said frame means.
Claim 3
Dependent Claim
31 words
The dental chair of claim 1 wherein said back portion comprises a hollow frame member having front and back panels securEd thereto, said lever element being secured to said front panel.
Claim 4
Dependent Claim
25 words
The dental chair of claim 2 wherein said panel has an access opening provided therein in communication with said upper end of said lever element.
Claim 5
Dependent Claim
22 words
The dental chair of claim 1 wherein said second pair of arms dwell in a plane below said first pair of arms.
Claim 6
Dependent Claim
20 words
The dental chair of claim 1 wherein said lever element comprises a plate means having an arcuate lower end portion.
Claim 7
Dependent Claim
32 words
The dental chair of claim 1 wherein a pair of spaced apart ears are secured to said frame means, said lever element being pivotally secured to said ears above its lower end.
Claim 8
Dependent Claim
17 words
The dental chair of claim 6 wherein said ears extend rearwardly and upwardly from said frame means.
Claim 9
Dependent Claim
43 words
The chair of claim 1 wherein said clevis element has a limit switch actuating arm which deactivates said motor at the extreme limits of travel of said member threadably mounted on said screw shaft, thereby preventing damage to the components of said chair.
Claim 10
Dependent Claim
28 words
The chair of claim 8 wherein the rearward end portion of said clevis element is slightly offset with respect to the forward end portion of said clevis element.
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) | 1977-07-15 | 1978-01-14 | 1978-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-15 | 1982-01-14 | 1982-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-15 | 1986-01-14 | 1986-07-16 | $7700.00 | Window Closed / Lapsed |