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US4177665A Expired / Lapsed US ⏱️ 0.0 years remaining

Cold flow forming

Assignee: Individual
•
Filing: 1978-04-03
•
Granted: 1979-12-11
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Expires: 1998-04-03
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Abstract

Abstract A process and associated apparatus are provided for producing cold flow formed items from slugs. First and second dies are aligned for relative movement axially towards and away from one another. The dies have respective opposed first and second faces and the first face defines a cavity having portions including generally axial walls. The first die has a peripheral chamfer extending axially away from the first face and a sleeve is provided containing the dies to combine with outer parts of the second face and the peripheral chamfer to define an annular space. The slug is formed into the item by causing relative movement between the dies to impact the slug and then causing further relative movement so that the slug is caused to flow into contact with the axial walls and also into the annular space so that destructive forces applied to the axial walls are countered by forces applied to the chamfer thereby stabilizing the material of the first die between the axial walls and the chamfer. A slug for use with the die set is also provided.

Inventors

  • 👤 Heinz P. Schurmann

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 19:03
CPC Classifications
B; B21; B21J; B21J13/00; B21J13/02; B21C; B21C23/00; B21C23/01; B21C23/02; B21C23/03; B21J5/00; B21J5/02

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 189 words
A process for producing cold flow formed items from slugs, the process comprising the steps: providing a slug to be cold flow formed; providing first and second dies aligned for relative movement axially towards and away from one another, the dies having respective opposed first and second faces and the first face defining a cavity having portions including generally axial walls, and the first die having a peripheral chamfer extending axially away from the first face; providing a sleeve containing the first and second dies to combine with outer parts of the second face and the peripheral chamfer to define an annular space; placing the slug between said dies inside the sleeve; causing said relative movement between the dies to create an impact between the slug and the dies; causing said relative movement to continue so that the slug is caused to cold flow into contact with said generally axial walls and also into the annular space so that destructive forces applied to the axial walls are countered by forces applied to the chamfer thereby stabilizing the material of the first die between the axial walls and the chamfer.
Claim 2
Dependent Claim 189 words
A process for producing cold flow formed items from slugs, the process comprising the steps: providing a slug to be cold flow formed; providing first and second dies aligned for relative movement axially towards and away from one another, the dies having respective opposed first and second faces and the first face defining a cavity having portions including generally axial walls, and the first die having a peripheral chamfer extending axially away from the first face; providing a sleeve containing the first and second dies to combine with outer parts of the second face and the peripheral chamfer to define an annular space; placing the slug between said dies inside the sleeve; causing said relative movement between the dies to create an impact between the slug and the dies; causing said relative movement to continue so that the slug is caused to cold flow into contact with said generally axial walls and also into the annular space so that destructive forces applied to the axial walls are countered by forces applied to the chamfer thereby stabilizing the material of the first die between the axial walls and the chamfer.
Claim 3
Dependent Claim 39 words
A process as claimed in claim 1 in which the second die defines second axial walls and a second peripheral chamfer so that the annular space is then defined by the first and second peripheral chamfers and the sleeve.
Claim 4
Dependent Claim 24 words
A process as claimed in claim 1 wherein the slug is provided having a crowned impact surface for impact engagement with said first face.
Claim 5
Dependent Claim 31 words
A process as claimed in claim 2 in which the slug is provided having respective first and second crowned impact surfaces for respective impact engagement with said first and second faces.
Claim 6
Dependent Claim 51 words
A process as claimed in claim 3 in which the slug is provided with the impact surface having a projected plan area at least approximating the planar surface area of the first face surrounded by the peripheral chamfer, and the projected plan area having a similar shape to the first face.
Claim 7
Dependent Claim 63 words
A process as claimed in claim 4 in which the slug is provided with each of the impact surfaces having a projected plan area at least approximating the planar surface area of the respective first and second faces of the dies surrounded by the associated peripheral chamfers, each of the projected plan areas having similar shapes to the respective first and second faces.
Claim 8
Dependent Claim 26 words
A process as claimed in claim 3 in which the slug is provided with the crowned impact surface defining an included angle greater than 84 degrees.
Claim 9
Dependent Claim 28 words
A process as claimed in claim 4 in which the slug is provided with each of the crowned impact surfaces having an included angle greater than 84 degrees.
Claim 10
Dependent Claim 28 words
A process as claimed in claim 1 in which the first die is provided with the peripheral chamfer defining an angle of about 15 degrees with the sleeve.
Claim 11
Dependent Claim 29 words
A process as claimed in claim 2 in which the first and second dies are provided with respective peripheral chamfers having angles of about 15 degrees with the sleeve.
Claim 12
Dependent Claim 159 words
A die set for use in cold flow forming an item from a slug, the die set comprising: first and second dies having respective opposed first and second faces, the first face defining a cavity having portions including generally axial walls, and the first die having a peripheral chamfer extending axially away from the first face; and a sleeve adapted to contain the dies with the dies aligned for relative movement axially towards and away from one another, the sleeve combining with outer parts of the second face and the peripheral chamfer to define an annular space so that upon causing cold flow forming to take place between the dies the slug will flow into contact with the generally axial walls and also into the annular space so that destructive forces applied to the axial walls are countered by forces applied to the chamfer thereby stabilizing the material of the first die between the axial walls and the chamfer.
Claim 13
Dependent Claim 159 words
A die set for use in cold flow forming an item from a slug, the die set comprising: first and second dies having respective opposed first and second faces, the first face defining a cavity having portions including generally axial walls, and the first die having a peripheral chamfer extending axially away from the first face; and a sleeve adapted to contain the dies with the dies aligned for relative movement axially towards and away from one another, the sleeve combining with outer parts of the second face and the peripheral chamfer to define an annular space so that upon causing cold flow forming to take place between the dies the slug will flow into contact with the generally axial walls and also into the annular space so that destructive forces applied to the axial walls are countered by forces applied to the chamfer thereby stabilizing the material of the first die between the axial walls and the chamfer.
Claim 14
Dependent Claim 40 words
A die set as claimed in claim 11 in which the second die defines second axial walls and a second peripheral chamfer so that the annular space is then defined by the first and second peripheral chamfers and the sleeve.
Claim 15
Dependent Claim 25 words
A die set as claimed in claim 11 in which the peripheral chamfer defines an angle of about 15 degrees with the sleeve after assembly.
Claim 16
Dependent Claim 25 words
A die set as claimed in claim 12 in which the peripheral chamfers each define angles of about 15 degrees with the sleeve after assembly.

References Cited (Backward Citations)

US376508A Cited
US1142419A Cited
US3962899A Cited
US4078415A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-12-10 1983-06-11 1983-12-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-12-10 1987-06-11 1987-12-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-12-10 1991-06-11 1991-12-11 $7700.00 Window Closed / Lapsed

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