Patent US4307475A successfully refreshed from Google Patents.
US4307475A
Expired / Lapsed
US
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Vacuum cuspidor
Assignee: A Dec Inc
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Filing: 1979-10-05
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Granted: 1981-12-29
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Expires: 1999-10-05
Abstract
Abstract The specification discloses an improved dental cuspidor having a vacuum drain means. The specification also discloses a drain having a drain chamber of which one side is formed by a diaphragm so that when water reaches a given height in the chamber, the diaphragm actuates an air valve to drive a piston to open a drain valve to a vacuum drain.
Inventors
- 👤 Theodore E. Schmidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:08
CPC Classifications
A; A61; A61C; A61C17/00; A61C17/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
147 words
An improved dental cuspidor, a cuspidor bowl, a drain means for the cuspidor comprising a cylindrical trap body having an open vertical side, diaphragm means closing the vertical side, a drain opening in the side wall of said trap body, a poppet valve for closing said opening including a stem extending exteriorly of said body and adapted to be grasped manually for manual operation of said poppet valve, spring means operatively connected to said poppet valve and biasing the same to closed position, a cylinder encompassing said stem and a piston on said stem slidably engaging the cylinder wall, a source of fluid under pressure connected to said cylinder to cause said piston to move said poppet valve to open position against the bias of said spring, and valve means actuated by the diaphragm means for controlling the flow of fluid from said source to said cylinder.
Claim 2
Dependent Claim
147 words
An improved dental cuspidor, a cuspidor bowl, a drain means for the cuspidor comprising a cylindrical trap body having an open vertical side, diaphragm means closing the vertical side, a drain opening in the side wall of said trap body, a poppet valve for closing said opening including a stem extending exteriorly of said body and adapted to be grasped manually for manual operation of said poppet valve, spring means operatively connected to said poppet valve and biasing the same to closed position, a cylinder encompassing said stem and a piston on said stem slidably engaging the cylinder wall, a source of fluid under pressure connected to said cylinder to cause said piston to move said poppet valve to open position against the bias of said spring, and valve means actuated by the diaphragm means for controlling the flow of fluid from said source to said cylinder.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-12-28 | 1985-06-29 | 1985-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-28 | 1989-06-29 | 1989-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-28 | 1993-06-29 | 1993-12-29 | $7700.00 | Window Closed / Lapsed |