US3172846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hirs filter process
Assignee: —
•
Filing: —
•
Granted: 1965-03-09
•
Expires: 1982-03-09
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:40
CPC Classifications
B; B01; B01D; B01D37/00; B01D37/02; B01D29/00; B01D29/11; B01D29/13; B01D29/15; B01D29/50; B01D29/52; B01D29/62; B01D29/66; B01D37/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
IN A METHOD OF FILTERING CONTAMINATED LIQUID BY FLOWING THE LIQUID THROUGH A FILTER CONTAINER FOR REMOVAL OF CONTAMINANTS AT FILTER ELEMENTS DISPOSED IN SAID CONTAINER AND PRE-COATED WITH A FILTER MEDIUM, SAID CONTAINER COMMUNICATING WITH A SEPARATE SLUDGE TANK, THE STEPS OF PNEUMATICALLY BLOWING DOWN IN THE CONTAINER CONTENTS INCLUDING CONTAMINATED MEDIUM INTO SAID SEPARATE SLUDGE TANK, THEREBY PROGRESSIVELY EMPTYING SAID CONTAINER; DURING THE PROGRESSIVE EMPTYING OF SAID CONTAINER, FORMING A SLURRY OF FRESH PRE-COAT MEDIUM AND LIQUID; AND, AT THE CONCLUSION OF SAID BLOWING DOWN STEPS, REFILLING SAID CONTAINER WITH LIQUID INCLUDING SAID SLURRY, AGAIN FLOWING CONTAMINATED LIQUID THROUGH SAID CONTAINER TO DEPOSIT SAID FRESH PRE-COAT MEDIUM ON SAID FILTER ELEMENTS, AND INITIATING THE FILTRATION OF SAID SLUDGE AT A SECOND NONPRE-COATED MEDIUM COMMUNICATING WITH SAID SLUDGE TANK.
Claim 2
Dependent Claim
130 words
IN A METHOD OF FILTERING CONTAMINATED LIQUID BY FLOWING THE LIQUID THROUGH A FILTER CONTAINER FOR REMOVAL OF CONTAMINANTS AT FILTER ELEMENTS DISPOSED IN SAID CONTAINER AND PRE-COATED WITH A FILTER MEDIUM, SAID CONTAINER COMMUNICATING WITH A SEPARATE SLUDGE TANK, THE STEPS OF PNEUMATICALLY BLOWING DOWN IN THE CONTAINER CONTENTS INCLUDING CONTAMINATED MEDIUM INTO SAID SEPARATE SLUDGE TANK, THEREBY PROGRESSIVELY EMPTYING SAID CONTAINER; DURING THE PROGRESSIVE EMPTYING OF SAID CONTAINER, FORMING A SLURRY OF FRESH PRE-COAT MEDIUM AND LIQUID; AND, AT THE CONCLUSION OF SAID BLOWING DOWN STEPS, REFILLING SAID CONTAINER WITH LIQUID INCLUDING SAID SLURRY, AGAIN FLOWING CONTAMINATED LIQUID THROUGH SAID CONTAINER TO DEPOSIT SAID FRESH PRE-COAT MEDIUM ON SAID FILTER ELEMENTS, AND INITIATING THE FILTRATION OF SAID SLUDGE AT A SECOND NONPRE-COATED MEDIUM COMMUNICATING WITH SAID SLUDGE TANK.
References Cited (Backward Citations)
US2366903A
Cited
US2423172A
Cited
US2952363A
Cited
US3037635A
Cited
US2828862A
Cited
US2867325A
Cited
US2867324A
Cited
US2909285A
Cited
US2867327A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-03-08 | 1968-09-07 | 1969-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-08 | 1972-09-07 | 1973-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-08 | 1976-09-07 | 1977-03-09 | $7700.00 | Window Closed / Lapsed |