US3662584A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sheet metal forming apparatus
Assignee: Niagara Machine and Tool Works
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Filing: 1970-06-15
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Granted: 1972-05-16
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Expires: 1990-06-15
Abstract
Abstract A sheet metal forming apparatus comprising an upstanding member having a pressure foot on the upper end thereof movable into a work clamping position. A rotatable forming member engages the free edge of the workpiece and reversely bends it about a lip formation provided on the pressure foot. Prior to the completion of the bending operation, the pressure foot is pivotally withdrawn from the workpiece to permit the forming member to overbend the reversely bent portion of the workpiece beyond 180* and permit the natural resiliency of the material to restore the reversely bent portion to a true 180* reverse bend.
Inventors
- 👤 Clarence O Jones Jr
- 👤 Fred F Snuszki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:04
CPC Classifications
B; B21; B21D; B21D19/00; B21D19/08; B21D5/00; B21D5/04; B21D5/042
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
166 words
Apparatus for forming a reverse bend along an edge of a sheet of metal comprising: a frame, a pressure foot mounted on said frame and having a lip formation along an edge thereof, a stationary clamping member mounted on said frame above said pressure foot, means for raising said pressure foot for clamping a workpiece between said clamping member and said pressure foot with the marginal edge of said workpiece protruding beyond said clamping member and said pressure foot, means engageable with said marginal edge of said workpiece for reversely bending said marginal edge about said lip formation, means for withdrawing said pressure foot from said workpiece to disengage said lip formation from said workpiece while said bending means is maintained engaged with said marginal edge for continued bending thereof, means operable subsequent to said disengagement for continuing the movement of said bending means to continue reverse bending to the degree required to compensate for springback and produce a final reverse bend of the required degree.
Claim 2
Dependent Claim
166 words
Apparatus for forming a reverse bend along an edge of a sheet of metal comprising: a frame, a pressure foot mounted on said frame and having a lip formation along an edge thereof, a stationary clamping member mounted on said frame above said pressure foot, means for raising said pressure foot for clamping a workpiece between said clamping member and said pressure foot with the marginal edge of said workpiece protruding beyond said clamping member and said pressure foot, means engageable with said marginal edge of said workpiece for reversely bending said marginal edge about said lip formation, means for withdrawing said pressure foot from said workpiece to disengage said lip formation from said workpiece while said bending means is maintained engaged with said marginal edge for continued bending thereof, means operable subsequent to said disengagement for continuing the movement of said bending means to continue reverse bending to the degree required to compensate for springback and produce a final reverse bend of the required degree.
Claim 3
Dependent Claim
56 words
Apparatus according to claim 1 wherein said means for raising said pressure foot comprises a rotatable shaft, a cam mounted on said shaft, a rocker arm connected at one end to said pressure foot and having a cam follower engageable with said cam, the other end of said rocker arm being pivotally mounted on said frame.
Claim 4
Dependent Claim
41 words
Apparatus according to claim 1 wherein said means for withdrawing said pressure foot from said workpiece comprises a rotatable shaft, a cam mounted on said shaft, a bracket connected to said pressure foot and having a cam follower engaging said cam.
Claim 5
Dependent Claim
31 words
Apparatus according to claim 1 wherein said bending means comprises a forming member rotatable on an axis parallel to said marginal edge of said workpiece and engageable against said marginal edge.
Claim 6
Dependent Claim
37 words
Apparatus according to claim 4 wherein said forming member is secured to an elongated member extending parallel to the marginal edge of said workpiece and having gear teeth for rotation of said member on said parallel axis.
Claim 7
Dependent Claim
17 words
Apparatus according to claim 5 including drive means engaging said gear teeth for rotating said forming member.
Claim 8
Dependent Claim
39 words
Apparatus according to claim 6 wherein said drive means comprises a power source, a rotatable crankshaft operatively connected to said power source and gear means on said crankshaft having driving connection with said gear teeth on said forming member.
References Cited (Backward Citations)
GB190906629A
Cited
US1192797A
Cited
US1530502A
Cited
US2028869A
Cited
US2394193A
Cited
US2687162A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |