US3683559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for producing perforated sheet material
Assignee: Johnson and Johnson
•
Filing: 1970-10-05
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Granted: 1972-08-15
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Expires: 1990-10-05
Abstract
Abstract Apparatus for perforating sheet materials comprising a pair of rotatable rolls which form a nip. One roll has raised projections on its surface and the other roll has an abrading surface. The abrading surface roll has a greater surface linear speed than the other roll.
Inventors
- 👤 Frank Kalwaites
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:30
CPC Classifications
B; B24; B24B; B24B19/00; B24B19/22; B24B19/223; B26; B26F; B26F1/00; B26F1/24
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
142 words
Apparatus for perforating sheet material comprising: a pair of rotatable rolls cooperating to form a nip through which the sheet material to be perforated passes, the surface of one of said rolls consisting of from 100 to 150,000 raised projections per square foot of roll area, the ends of said projections being flat and having individual areas of from about .0001 square inch to 0.1 square inch, the outer end area of said projections occupying from about 7 percent to 11 percent of the area of the circular surface passing about the ends of the projection of said roll, the other roll having an abrading surface positioned to contact the flat area of said projections at said nip, said abrading roll rotating at a surface linear speed of at least two times the surface linear speed of said roll having raised projections.
Claim 2
Dependent Claim
142 words
Apparatus for perforating sheet material comprising: a pair of rotatable rolls cooperating to form a nip through which the sheet material to be perforated passes, the surface of one of said rolls consisting of from 100 to 150,000 raised projections per square foot of roll area, the ends of said projections being flat and having individual areas of from about .0001 square inch to 0.1 square inch, the outer end area of said projections occupying from about 7 percent to 11 percent of the area of the circular surface passing about the ends of the projection of said roll, the other roll having an abrading surface positioned to contact the flat area of said projections at said nip, said abrading roll rotating at a surface linear speed of at least two times the surface linear speed of said roll having raised projections.
Claim 3
Dependent Claim
22 words
Apparatus according to claim 1 wherein the roll having raised projections has about 20,000 raised projections per square foot of roll area.
Claim 4
Dependent Claim
31 words
Apparatus according to claim 1 wherein the roll having raised projections has about 20,000 raised projections per square foot of roll area and said abrading surface comprises closely spaced wire points.
References Cited (Backward Citations)
US2218674A
Cited
US3255496A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |