Patent US3518199A successfully refreshed from Google Patents.
US4773993A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for purifying and dispensing water with stagnation preventing means
Assignee: Hitachi Ltd
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Filing: 1987-03-06
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Granted: 1988-09-27
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Expires: 2007-03-06
Abstract
Abstract An apparatus for producing pure water from raw water, comprises a reverse osmotic membrane unit, a polisher, an ultraviolet sterilizer, a high pressure pump for forcing raw water to flow through a reverse osmotic membrane in said reverse osmotic membrane unit to produce pure water permeated therethrough, and for feeding pure water to a use point, and a circulating line extending between said use point and a suction side of said high pressure pump for circulating pure water therebetween. With this construction, degradation of pure water due to stagnation is avoided.
Inventors
- 👤 Hiroaki Yoda
- 👤 Minoru Kuroiwa
- 👤 Yoshitsugu Itoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:30
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/02; B01D61/08; B01D65/00; B01D2311/00; B01D2311/06; B01D2313/00; B01D2313/18; B01D2313/24; B01D2313/243
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
160 words
An apparatus for producing pure water from raw water, the apparatus comprising: a reverse osmotic membrane means; a purifying means connected to said reverse osmotic membrane means, said purifying means including a polisher and an ultraviolet sterilizer; a high pressure pump means having a suction side and a discharge side, said high pressure pump means having its discharge side connected to said reverse osmotic membrane means for forcing raw water to flow through a reverse osmotic membrane in said reverse osmotic membrane means to produce pure water permeated therethrough and for feeding said pure water through said purifying means and to a use point where the pure water can be used; and a circulating line means extending between said use point and the suction side of said high pressure pump means for circulating unused pure water from said use point to the suction side of said high pressure pump means for recirculation through said apparatus without storage in a tank.
Claim 2
Independent Claim
160 words
An apparatus for producing pure water from raw water, the apparatus comprising: a reverse osmotic membrane means; a purifying means connected to said reverse osmotic membrane means, said purifying means including a polisher and an ultraviolet sterilizer; a high pressure pump means having a suction side and a discharge side, said high pressure pump means having its discharge side connected to said reverse osmotic membrane means for forcing raw water to flow through a reverse osmotic membrane in said reverse osmotic membrane means to produce pure water permeated therethrough and for feeding said pure water through said purifying means and to a use point where the pure water can be used; and a circulating line means extending between said use point and the suction side of said high pressure pump means for circulating unused pure water from said use point to the suction side of said high pressure pump means for recirculation through said apparatus without storage in a tank.
Claim 3
Dependent Claim
30 words
An apparatus according to claim 1, further comprising a check valve means disposed in said circulating line means for preventing raw water from flowing backward into said circulating line means.
Claim 4
Dependent Claim
49 words
An apparatus according to claim 1, further comprising an opening and closing valve means disposed in said circulating line means, and a relief valve means disposed in parallel to said opening and closing valve means, said opening and closing valve being closed when said apparatus is brought into operation.
Claim 5
Dependent Claim
41 words
An apparatus according to claim 1, further comprising an ejector means disposed in said circulating line means and a washing liquid tank means connected with said ejector means for supplying a washing liquid through said ejector means into said circulating line
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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) | 1991-09-27 | 1992-03-28 | 1992-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-27 | 1996-03-28 | 1996-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-27 | 2000-03-28 | 2000-09-27 | $7700.00 | Window Closed / Lapsed |