US 12,280,415 B2
Cold working apparatus and a method for cold working a blank
Lars Sandberg, Luleå (SE); Joakim Innala, Luleå (SE); and Petter Ulfberg, Luleå (SE)
Assigned to Autotech Engineering S.L., Bizkaia (ES)
Appl. No. 17/607,157
Filed by Autotech Engineering S.L., Bizkaia (ES)
PCT Filed Apr. 17, 2020, PCT No. PCT/SE2020/050395
§ 371(c)(1), (2) Date Oct. 28, 2021,
PCT Pub. No. WO2020/222687, PCT Pub. Date Nov. 5, 2020.
Claims priority of application No. 1950512-2 (SE), filed on Apr. 29, 2019.
Prior Publication US 2022/0203427 A1, Jun. 30, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. B21D 22/20 (2006.01); B21D 22/02 (2006.01); B21D 37/01 (2006.01)
CPC B21D 22/20 (2013.01) [B21D 22/02 (2013.01); B21D 37/01 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A cold working apparatus for forming a blank, the cold working apparatus comprising a first die and a second die, wherein the first die has at least one die cavity, and the second die has at least one die protrusion, the die protrusion of the second die being complementary to the die cavity of the first die, wherein the cold working apparatus is configured to, by means of the first and second dies, press form the blank placed between the first and second dies, wherein at least one of the first and second dies has a draw radius, wherein a member is attached to the die which has the draw radius, at least a portion of the member being positioned adjacent to or on the draw radius, wherein the member defines a first press forming surface, and the die holding the member defines a second press forming surface outside the first press forming surface, wherein the member consists of an adhesive tape having a first surface and a second surface, wherein the first surface of the adhesive tape forms the first press forming surface of the member, and the second surface of the adhesive tape is provided with at least one adhesive substance, and wherein the second surface of the adhesive tape is attached to the die by means of the at least one adhesive substance, wherein the member and the die, which holds the member, are configured such that during the same press forming, a first friction arises between the blank and the first press forming surface when the blank is in contact with the member and a second friction arises between the blank and the second press forming surface when the blank is in contact with the die which holds the member, the first friction being lower than the second friction.