Stretch forming die

Patent metadata

Field	Value
Publication number	US-10933458-B2
Application number	US-201816225748-A
Country	US
Kind code	B2
Filing date	Dec 19, 2018
Priority date	Dec 19, 2018
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A stamping press binder assembly for forming a finished stamped product from a blank includes an upper die for at least partially forming the finished stamped product, a stationary punch, an inner lower binder, and an outer lower binder. The inner and outer lower binders are both supported by a single cushion.

First claim

What is claimed is:

1. A stamping press binder assembly for forming a finished stamped product from a blank, the press binder assembly comprising:
an upper die for at least partially forming the finished stamped product;
a stationary punch positioned below the upper die;
an inner lower binder;
an outer lower binder moveably positioned on the inner lower binder; and
a single cushion;
wherein the inner and outer lower binders are both supported by the single cushion, and
wherein the cushion is programmable and includes a plurality of cushion pins extending between the inner lower binder and at least one first high pressure fluid cylinder, and wherein the outer lower binder is supported by a die cylinder having a piston and a second high pressure fluid cylinder, wherein the binder assembly further comprises a controller configured to:
set the programmable cushion with a first predetermined cushion force and move the upper die downward a first predetermined distance;
set the programmable cushion with a second predetermined cushion force and move the upper die further downward a second predetermined distance such that the die cylinder is at least partially compressed; and
set the programmable cushion with a third predetermined cushion force and move the upper die further downward a third predetermined distance such that a plurality of stinger teeth on an upper surface of the inner lower binder penetrate the blank to facilitate substantially locking sheet draw-in.

2. The binder assembly of claim 1 , wherein the outer lower binder is supported by the inner lower binder and configured to nest within a recessed area of the inner lower binder.

3. The binder assembly of claim 1 , wherein the second high pressure fluid cylinder is a nitrogen cylinder.

4. The binder assembly of claim 1 , wherein the inner lower binder has an upper surface with a plurality of stinger teeth configured to penetrate the blank.

5. The binder assembly of claim 4 , wherein the stinger teeth have a pyramidal shape.

6. The binder assembly of claim 5 , wherein the plurality of stinger teeth are formed on a stinger insert removably received within a recess formed on the upper surface of the inner lower binder.

7. The binder assembly of claim 6 , wherein the stinger insert is removably coupleable to the inner lower binder.

8. The binder assembly of claim 7 , wherein the stinger insert includes an outer surface from which the plurality of stinger teeth extend, and an aperture extending therethrough configured to receive a fastener.

9. The binder assembly of claim 8 , wherein the aperture is a threaded aperture.

10. The binder assembly of claim 1 , wherein the second predetermined force is greater than the first predetermined force.

11. The binder assembly of claim 10 , wherein the third predetermined force is greater than the second predetermined force.

12. The binder assembly of claim 11 , wherein the first predetermined force is 20 tons, the second predetermined force is 40 tons, and the third predetermined force is 100 tons.

13. A method of forming a finished stamped product from a blank in a stamping press binder assembly having an upper die, a stationary punch, an inner lower binder, an outer lower binder, and a die cylinder disposed on the inner lower binder and supporting the outer lower binder, wherein the inner and outer lower binders are both supported by a single cushion, the method comprising:
positioning the blank on the outer lower binder and the stationary punch;
setting the cushion with a first predetermined cushion force and moving the upper die downward a first predetermined distance;
setting the cushion with a second predetermined cushion force and moving the upper die further downward a second predetermined distance such that the die cylinder is at least partially compressed; and
setting the cushion with a third predetermined cushion force and moving the upper die further downward a third predetermined distance such that a plurality of stinger teeth on an upper surface of the inner lower binder penetrate the blank to facilitate substantially locking sheet draw-in to reduce springback.

14. The method of claim 13 , further comprising removably coupling a stinger insert to the inner lower binder, the stinger insert having an outer surface with the plurality of stinger teeth extending therefrom configured to penetrate the blank.

15. The method of claim 14 , wherein the stinger insert is removably coupled within a recess formed in an upper surface of the inner lower binder.

16. The method of claim 15 , further comprising forming the stinger teeth with a pyramidal shape.

Assignees

• Zhou Dajun
• Du Changqing
• Miller Robert D
• Siemen Richard J
• Fca Us Llc

Inventors

• Zhou Dajun
• Du Changqing
• Miller Robert D
• Siemen Richard J

Classifications

• B21D25/02

  by pulling over a die · CPC title

• B21D22/22

  with devices for holding the edge of the blanks (B21D22/24 - B21D22/30 take precedence; shaping over a die without external former B21D11/02) · CPC title

• B21D22/06

  having relatively-movable die parts · CPC title

• B21D24/08 Primary

  Pneumatically or hydraulically loaded blank holders · CPC title