US3789649A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Draw ring for cans
Assignee: Alcoa Corp
•
Filing: 1973-01-16
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Granted: 1974-02-05
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Expires: 1993-01-16
Abstract
Abstract An improved die means for sheet metal drawing is provided which permits lower pad pressures and mitigates the problem of earring by the provisions of concentric depressions in at least one of the draw rings.
Inventors
- 👤 E Clowes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:05
CPC Classifications
B; B21; B21D; B21D24/00; B21D24/04; B21D22/00; B21D22/20; B21D22/22
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
127 words
In a drawing die apparatus for drawing shaped members from sheet material wherein the sheet is peripherally engaged respectively by opposing surfaces of a pair of dies while a central post member on one of the dies draws the sheet material into a corresponding cylinder on the other die, the improvement wherein: at least one of said opposing surfaces is provided with a plurality of concentric depressions each having a width of about 0.09-0.15 inch, and forming an angle with the planar portion of the die not exceeding about 12* separated by planar portions which are opposed by planar portions of the opposed die surface defining the extremities of the opposed surfaces to engage said sheet material in a common plane without deformity of said sheet material.
Claim 2
Dependent Claim
127 words
In a drawing die apparatus for drawing shaped members from sheet material wherein the sheet is peripherally engaged respectively by opposing surfaces of a pair of dies while a central post member on one of the dies draws the sheet material into a corresponding cylinder on the other die, the improvement wherein: at least one of said opposing surfaces is provided with a plurality of concentric depressions each having a width of about 0.09-0.15 inch, and forming an angle with the planar portion of the die not exceeding about 12* separated by planar portions which are opposed by planar portions of the opposed die surface defining the extremities of the opposed surfaces to engage said sheet material in a common plane without deformity of said sheet material.
Claim 3
Dependent Claim
45 words
The improvement of claim 1 wherein said width of each of said depressions is greater than the width of the planar portion between adjacent depressions to provide a substantial reduction in contact area between the opposing die surfaces and the sheet material being drawn therebetween.
Claim 4
Dependent Claim
34 words
The improvement of claim 1 wherein the depressions are arcuate in cross section and the radius of the arc defined by each of said depressions is about 4.25 times the width of the depression.
Claim 5
Dependent Claim
24 words
The improvement of claim 1 wherein the depth of each of said depressions does not exceed about one-third of the thickness of sheet material.
Claim 6
Dependent Claim
118 words
Improved draw ring members for peripheral engagement of sheet metal stock during a drawing operation comprising opposing draw ring surfaces wherein at least one of said surfaces contains a plurality of concentric concave channels therein, each of said concave channels having a width of approximately 0.09-0.15 inch, a depth not exceeding about one-third of the thickness of the sheet metal to be engaged by said opposing surfaces, and an angle of intersection with the planar portions of the surface therebetween not exceeding about 12*, each of said planar portions having a width not exceeding the width of said channel to provide a reduction in contact area between the opposing die surfaces and the sheet metal being drawn therebetween.
Claim 7
Dependent Claim
118 words
Improved draw ring members for peripheral engagement of sheet metal stock during a drawing operation comprising opposing draw ring surfaces wherein at least one of said surfaces contains a plurality of concentric concave channels therein, each of said concave channels having a width of approximately 0.09-0.15 inch, a depth not exceeding about one-third of the thickness of the sheet metal to be engaged by said opposing surfaces, and an angle of intersection with the planar portions of the surface therebetween not exceeding about 12*, each of said planar portions having a width not exceeding the width of said channel to provide a reduction in contact area between the opposing die surfaces and the sheet metal being drawn therebetween.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |