Patent US3820186A successfully refreshed from Google Patents.
US3820186A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Elongated hole brush
Assignee: Tennant Co
•
Filing: 1972-03-29
•
Granted: 1974-06-28
•
Expires: 1992-03-29
Abstract
Abstract A ROTARY TUBULAR BRUSH HAVING A TUBULAR CORE, SAID CORE HAVING AXIALLY ELONGATED TUFT HOLES, AND TUFTS SECURED IN THE HOLES BY STAPLES. THE TUFT HOLES MAY BE FORMED BY, FOR EXAMPLE, A MACHINE THAT MOVES A ROTARY DRILL FOR DRILLING CIRCULAR HOLES FIRST DOWNWARDLY AND THEN UPWARDLY WHILE THE CORE IS MOVED AXIALLY. ALSO THE TUFT HOLES MAY BE FORMED BY BURNING, CASTING OR PUNCHING. ADDITIONALLY, BRUSHED OTHER THAN TUBULAR BRUSHED MAY HAVE TUFT HOLES FOR TUFTS THAT ARE OF A GREATER CROSS-SECTIONAL DIMENSION IN ONE DIRECTION THAN THE OTHER IN A PLANE PERPENDICULAR TO THE DEPTH DIRECTION OF THE HOLES.
Inventors
- 👤 R Peabody
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:33
CPC Classifications
A; A46; A46B; A46B13/00; A46B13/001
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |