US 12,121,959 B2
Three-plate die casting mold having a sprue system and improved sprue separation, and die casting method
Fritz Hirning, Laichingen (DE); Andre Schaefer, Rottenburg a.d.Laaber (DE); Jean-Marc Segaud, Landshut (DE); and Klaus-Peter Tucan, Landshut (DE)
Assigned to Bayerische Motoren Werke Aktiengesellschaft, Munich (DE)
Appl. No. 17/914,273
Filed by Bayerische Motoren Werke Aktiengesellschaft, Munich (DE)
PCT Filed Feb. 22, 2021, PCT No. PCT/EP2021/054309
§ 371(c)(1), (2) Date Sep. 23, 2022,
PCT Pub. No. WO2021/190847, PCT Pub. Date Sep. 30, 2021.
Claims priority of application No. 10 2020 108 022.0 (DE), filed on Mar. 24, 2020.
Prior Publication US 2023/0111366 A1, Apr. 13, 2023
Int. Cl. B22D 17/20 (2006.01); B22D 17/22 (2006.01)
CPC B22D 17/2076 (2013.01) [B22D 17/2236 (2013.01); B22D 17/2272 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A three-plate die casting mold for producing a metal die-cast part by die casting a molten metal, said die casting mold comprising:
a first mold part;
a second mold part;
a third mold part, wherein the third mold part is disposed between the first mold part and the second mold part;
a die cavity;
a sprue system, wherein the molten metal is feedable to the die cavity through the sprue system and wherein the sprue system has a plurality of feed channels that are disposed in the third mold part and open into the die cavity, wherein the plurality of feed channels in the third mold part that open into the die cavity have a respective tapering at a die cavity-side end, and wherein the respective tapering locally decreases a channel cross section such that a predetermined breaking point is generated during a die casting operation which allows a defined separation of the metal die-cast part from a sprue web created in the sprue system when, during opening of the three-plate die casting mold, the first mold part is separated from the third mold part with the third mold part remaining closed on the second mold part; and
a plurality of pins that extend completely through the first mold part and project into respective feed channels in the third mold part when the three-plate die casting mold is closed, wherein the plurality of pins each have a respective conical shape at a front end, and wherein the plurality of pins are each formed with an undercut contour that engages with a respective sprue web formed in the respective feed channel in a form-fit manner and as such retains the respective sprue web adjacent to the first mold part when, during the opening of the three-plate die casting mold, the first mold part is separated from the third mold part with the third mold part remaining closed on the second mold part so as to assist in the defined separation of the metal die-cast part from the respective sprue web.