Tools and methods for forming acoustic cores
An acoustic core may include an array of resonant cells configured as a plurality of resonant cell groups. The resonant cell groups may include a plurality of resonant cells configured as a partitioned resonant cell that include a converging resonant cell and a diverging resonant cell. The converging resonant cell and the diverging resonant cell may be defined by a plurality of cell walls integrally formed with one another and a partition integrally formed with the plurality of cell walls. The partition may at least partially delimit the converging resonant cell from the diverging resonant cell. The converging resonant cell may define an upper resonant space delimited by the partition and a top face of the array of resonant cells. The diverging resonant cell may define a lower resonant space delimited by the partition and a bottom face of the array of resonant cells.
1. A tooling assembly for forming an acoustic core, the tooling assembly comprising:
a plurality of forming tools, respective ones of the plurality of forming tools comprising a support member and a plurality of forming elements coupled to the support member;
wherein when the plurality of forming tools are in operating proximity to one another, a mold cavity defined at least in part by the plurality of forming elements corresponds to an acoustic core to be formed by the tooling assembly;
wherein the acoustic core comprises:
an array of resonant cells, the array of resonant cells comprising
a plurality of resonant cell groups, respective ones of the resonant cell groups comprising a plurality of resonant cells, at least some of the plurality of resonant cells comprising:
a partitioned resonant cell comprising a first converging resonant cell and a first diverging resonant cell, the first converging resonant cell and the first diverging resonant cell defined by a plurality of cell walls integrally formed with one another and a partition integrally formed with the plurality of cell walls, the partition at least partially delimiting the first converging resonant cell from the first diverging resonant cell;
wherein the first converging resonant cell defines an upper resonant space delimited by the partition and a top face of the array of resonant cells, and wherein the first diverging resonant cell defines a lower resonant space delimited by the partition and a bottom face of the array of resonant cells;
wherein at least some of the plurality of resonant cells comprise:
a coupled resonant cell, the coupled resonant cell defining a coupled resonant space comprising an antecedent resonant space and a subsequent resonant space, and the coupled resonant cell comprising at least one cell wall having one or more wall-apertures defining a pathway between the antecedent resonant space and the subsequent resonant space; and
wherein the coupled resonant cell is configured as a second diverging resonant cell, the coupled resonant cell located at portion of the acoustic core that has a concave curvilinear profile; or
wherein the coupled resonant cell is configured as a second converging resonant cell, the coupled resonant cell located at a portion of the acoustic core that has a curvilinear profile.
2. The tooling assembly of claim 1 , wherein the plurality of forming elements have a draft angle such that a cross-sectional dimension of the respective forming element decreases from a cross-sectional dimension proximal to the support member to a cross-sectional dimension distal from the support member.
3. The tooling assembly of claim 2 , wherein the draft angle of the respective ones of the plurality of forming elements allow for the acoustic core formed using the tooling assembly to release from the respective ones of the plurality of forming tools.
4. The tooling assembly of claim 2 , wherein the draft angle is provided by one or more dimensions of the resonant cells of the acoustic core configured to be formed by the tooling assembly.
5. The tooling assembly of claim 2 , wherein at least some of the resonant cells of the acoustic core have a convergence angle that corresponds to the draft angle of the respective forming elements and/or wherein at least some of the resonant cells of the acoustic core have a convergence angle that differs from the draft angle of the respective forming elements.
6. The tooling assembly of claim 2 , wherein the draft angle is from about 0.5 degrees to about 10 degrees.
7. The tooling assembly of claim 1 , wherein the tooling assembly comprises an injection molding assembly, or wherein the tooling assembly comprises a compression molding assembly, or wherein the tooling assembly comprises a press-forming assembly.
8. The tooling assembly of claim 1 , wherein the tooling assembly is configured to form an acoustic core that has a curvilinear profile.
9. The tooling assembly of claim 1 , wherein the plurality of forming tools comprise one or more sprue elements through which a moldable material may be injected into the mold cavity.
10. The tooling assembly of claim 1 , wherein the plurality of forming tools respectively comprise one or more ejector pins, the one or more ejector pins respectively extensible through the respective support member and/or through a respective forming element, the one or more ejector pins configured to push an acoustic core formed using the tooling assembly away from the respective forming tool and/or out of the mold cavity.
11. The tooling assembly of claim 1 , wherein at least some of the plurality of resonant cells comprise:
a third diverging resonant cell delimited by the top face and the bottom face; and/or
a third converging resonant cell delimited by the top face and the bottom face.
12. The tooling assembly of claim 1 , wherein the curvilinear profile is defined by the top face and/or the bottom face.
13. The tooling assembly of claim 12 , wherein the curvilinear profile comprises a convex curvilinear profile and/or a concave curvilinear profile.
14. The tooling assembly of claim 13 , wherein the array of resonant cells comprises a plurality of third diverging resonant cells defined by the top face and the bottom face at a location where the acoustic core has a convex curvilinear profile; and/or wherein the array of resonant cells comprises a plurality of third converging resonant cells defined by the top face and the bottom face at a location where the acoustic core has a concave curvilinear profile.
15. The tooling assembly of claim 1 , wherein the first converging resonant cell is configured as a high-frequency resonant cell defining a high-frequency resonant space, the high-frequency resonant cell being matched with the coupled resonant cell.
16. The tooling assembly of claim 13 , wherein at least some of the plurality of resonant cells comprise:
a first intermediate-frequency resonant cell defining an intermediate-frequency resonant space, the intermediate-frequency resonant space delimited by the top face and an additional partition, the additional partition separating the intermediate-frequency resonant space from the coupled resonant space; and
wherein the first intermediate-frequency resonant cell is configured as a converging resonant cell.
17. The tooling assembly of claim 1 , wherein the first converging resonant cell exhibits a convergence angle relative to a longitudinal axis of the first converging resonant cell of from 0.5 degrees to 30 degrees; and/or wherein the first diverging resonant cell exhibits a convergence angle relative to a longitudinal axis of the first diverging resonant cell of from −0.5 degrees to −30 degrees.
18. The tooling assembly of claim 1 , wherein the acoustic core comprises an injection molded acoustic core, or wherein the acoustic core comprises a press-formed acoustic core, or wherein the acoustic core comprises an additively manufactured acoustic core.
19. The tooling assembly of claim 1 , wherein the first converging resonant cell is realized at least in part by a cross-sectional thickness of one or more cell walls and/or at least in part by an angle or orientation of one or more cell walls; and/or wherein the first diverging resonant cell is realized at least in part by a cross-sectional thickness of one or more cell walls and/or at least in part by an angle or orientation of one or more cell walls.
20. A method of forming an acoustic core, the method comprising:
determining, with a tooling assembly configuration system, a configuration for a tooling assembly and/or a configuration for one or more forming tools for use in the tooling assembly;
making the one or more forming tools and/or assembling a tooling assembly that includes the one or more forming tools; and
forming the acoustic core using the tooling assembly that includes the one or more forming tools;
wherein the tooling assembly and/or the one or more forming tools have a configuration determined based at least in part on a configuration determined for the acoustic core;
wherein the acoustic core comprises:
an array of resonant cells, the array of resonant cells comprising
a plurality of resonant cell groups, respective ones of the resonant cell groups comprising a plurality of resonant cells, at least some of the plurality of resonant cells comprising:
a partitioned resonant cell comprising a first converging resonant cell and a first diverging resonant cell, the first converging resonant cell and the first diverging resonant cell defined by a plurality of cell walls integrally formed with one another and a partition integrally formed with the plurality of cell walls, the partition at least partially delimiting the first converging resonant cell from the first diverging resonant cell;
wherein the first converging resonant cell defines an upper resonant space delimited by the partition and a top face of the array of resonant cells, and wherein the first diverging resonant cell defines a lower resonant space delimited by the partition and a bottom face of the array of resonant cells;
wherein at least some of the plurality of resonant cells comprise:
a coupled resonant cell, the coupled resonant cell defining a coupled resonant space comprising an antecedent resonant space and a subsequent resonant space, and the coupled resonant cell comprising at least one cell wall having one or more wall-apertures defining a pathway between the antecedent resonant space and the subsequent resonant space; and
wherein the coupled resonant cell is configured as a second diverging resonant cell, the coupled resonant cell located at portion of the acoustic core that has a concave curvilinear profile; or
wherein the coupled resonant cell is configured as a second converging resonant cell, the coupled resonant cell located at a portion of the acoustic core that has a curvilinear profile.