US3581543A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Roll forming apparatus for sheet metal
Assignee: Niagara Machine and Tool Works
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Filing: 1969-06-23
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Granted: 1971-06-01
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Expires: 1989-06-23
Abstract
Abstract A pair of forming rolls for forming an outwardly opening return bent channel formation at an end of a cylindrical sheet metal workpiece such as a duct. The channel is formed in two operations. The workpiece is first inserted between the forming rolls to full depth against a gauge, the rolls are closed, and a relatively open V-shaped formation is formed. The rolls are then released and the workpiece is partially withdrawn until the apex of the V-shaped formation registers with a narrow annular groove in one roll and the rolls are again closed, whereby a plain cylindrical formation on the other roll engages the outer ends of the V formation and forces the same into the annular groove to complete a relatively narrow U-shaped return bent formation.
Inventors
- 👤 Lawrence L Hock
- 👤 Clarence O Jones Jr
- 👤 Henry Kardas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:31
CPC Classifications
B; B21; B21D; B21D17/00; B21D17/04; B21D53/00; B21D53/76; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49877
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
170 words
A pair of forming rolls for effecting successive roll forming operations along an edge of a sheet metal workpiece, said rolls being rotatably supported at one end thereof, one of said rolls being movable away from the other for introducing the edge of a workpiece therebetween, said rolls having first and second pass peripheral formations with the first pass formations toward the supported ends of the rolls and the second pass formations outwardly thereof, said first pass formations comprising a relatively open annular groove in one of said rolls and a complementary annular flange on the other roll to produce an open return bent formation along the edge of the workpiece, the second pass formations of said grooved roll comprising a narrower Ushaped annular groove, a peripheral portion of the flanged roll being adapted to engage the outer ends of the return bent formation of the workpiece and force the same into said U-shaped groove to produce a return bent formation with a relatively narrow space between the walls thereof.
Claim 2
Dependent Claim
170 words
A pair of forming rolls for effecting successive roll forming operations along an edge of a sheet metal workpiece, said rolls being rotatably supported at one end thereof, one of said rolls being movable away from the other for introducing the edge of a workpiece therebetween, said rolls having first and second pass peripheral formations with the first pass formations toward the supported ends of the rolls and the second pass formations outwardly thereof, said first pass formations comprising a relatively open annular groove in one of said rolls and a complementary annular flange on the other roll to produce an open return bent formation along the edge of the workpiece, the second pass formations of said grooved roll comprising a narrower Ushaped annular groove, a peripheral portion of the flanged roll being adapted to engage the outer ends of the return bent formation of the workpiece and force the same into said U-shaped groove to produce a return bent formation with a relatively narrow space between the walls thereof.
Claim 3
Dependent Claim
24 words
A pair of forming rolls in accordance with claim 1 wherein the relatively open annular groove and the complementary annular flange are generally V-shaped.
Claim 4
Dependent Claim
29 words
A pair of forming rolls in accordance with claim 1 wherein said open return bent formation has an external radius approximately one-half the width of said V-shaped annular groove.
Claim 5
Dependent Claim
29 words
A pair of forming rolls in accordance with claim 2 wherein said open return bent formation has an external radius approximately one-half the width of said V-shaped annular groove.
Claim 6
Dependent Claim
60 words
A pair of forming rolls in accordance with claim 1 wherein said one roll has a reduced diameter portion outwardly of said annular groove and said other roll has an increased diameter portion outwardly of said annular flange whereby said workpiece is provided with a tapering enlargement between the workpiece proper and the return bent formation at the end thereof.
Claim 7
Dependent Claim
60 words
A pair of forming rolls in accordance with claim 2 wherein said one roll has a reduced diameter portion outwardly of said annular groove and said other roll has an increased diameter portion outwardly of said annular flange whereby said workpiece is provided with a tapering enlargement between the workpiece proper and the return bent formation at the end thereof.
Claim 8
Dependent Claim
50 words
A pair of forming rolls in accordance with claim 5 wherein said U-shaped groove is formed in the reduced diameter portion of said one roll and the increased diameter portion of said other roll engages the return bent formation of the workpiece to force the same into said U-shaped groove.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |