Row based activation appartus for an electrochemical additive manufacturing system
Printhead for a 3D manufacturing system that uses metal electrodeposition to construct parts; embodiments utilize a grid of anodes to achieve high quality parts with features that may be small and detailed. To support grids with thousands or millions of anodes, the printhead may use matrix control with row and column drivers similar to display backplanes. Unlike display backplanes where the design goal is to display images using minimal current, the printhead may be optimized for high current density for fast electrodeposition, and for anode longevity. Current density may exceed 1000 mA per cm-squared, at least an order of magnitude greater than that of display backplanes. Anode longevity may be enhanced by using relatively large anodes compared to the grid pitch of the printhead, by lengthening the conductive paths through anodes, or both. Embodiments may be constructed by adding anode and insulation layers on top of matrix-controlled switching circuits.
1 . An electrochemical additive manufacturing system, comprising:
an array of row traces;
an array of column traces;
a row driver circuit electrically coupled to the array of row traces;
a column driver circuit electrically coupled to the array of column traces;
a power distribution circuit;
an array of deposition elements, wherein each deposition element of the array of deposition elements comprises:
a corresponding deposition anode of a plurality of deposition anodes of the array of deposition elements, each deposition anode of the plurality of deposition anodes is made of an insoluble conductive material and comprises an exposed surface configured to contact an electrolyte solution of the electrochemical additive manufacturing system, wherein the plurality of deposition anodes of the array of deposition elements are electrically connected in a plurality of rows and a plurality of columns; and
a corresponding deposition control circuit of a plurality of deposition control circuits of the array of deposition elements, the corresponding deposition control circuit being electrically coupled to the corresponding deposition anode, a corresponding one of the array of row traces, a corresponding one of the array of column traces, and the power distribution circuit, and operable to control an amount of electrical energy flowing into the corresponding deposition anode; and
a controller configured to:
position a surface of a cathode into the electrolyte solution such that a gap, filled with the electrolyte solution, is defined between the cathode and the deposition anodes;
activate only a first row trace of the array of row traces; and
simultaneously with activation of the first row trace of the array of row traces, activate at least one column trace of the array of column traces such that electrical energy flows into at least one first deposition anode of the plurality of deposition anodes electrically coupled to the first row trace of the array of row traces and the at least one column trace of the array of column traces to activate the at least one first deposition anode.
2 . The system according to claim 1 , wherein the controller is further configured to:
deactivate the first row trace of the array of row traces; and
after deactivating the first row trace of the array of row traces, activate only a second row trace of the array of row traces such that electrical energy flows into at least one second deposition anode electrically coupled to the second row trace of the array of row traces and the at least one column trace of the array of column traces to activate the at least one second deposition anode.
3 . The system according to claim 2 , wherein the controller is further configured to:
deactivate the at least one column trace of the array of column traces after the first row trace of the array of row traces is deactivated; and
simultaneously with activation of the second row trace of the array of row traces, activate at least another column trace of the array of column traces;
wherein the at least one second deposition anode is electrically coupled to the at least another column trace of the array of row traces.
4 . The system according to claim 1 , wherein the controller is further configured to sequentially activate and deactivate, row by row, individual row traces of the array of row traces.
5 . The system according to claim 4 , wherein the controller is further configured to maintain activation of the at least one column trace of the array of column traces as the individual row traces are sequentially activated and deactivated row by row.
6 . The system according to claim 1 , wherein the controller is further configured to estimate a deposition state of the at least one first deposition anode based on characteristics of the electrical energy in the at least one first deposition anode.
7 . The system according to claim 6 , wherein the controller is further configured to estimate the deposition state of the at least one first deposition anode based on a measured current of the electrical energy in the at least one first deposition anode.
8 . The system according to claim 6 , wherein the controller is further configured to estimate the deposition state of the at least one first deposition anode based on a measured voltage of the electrical energy in the at least one first deposition anode.
9 . The system according to claim 1 , wherein the controller is further configured to control an amount of electrical energy flowing into the at least one first deposition anode such that deposition of a quantity of material, corresponding with the amount of electrical energy, is deposited onto the cathode of the electrochemical additive manufacturing system.
10 . The system according to claim 9 , wherein:
the corresponding deposition control circuit comprises a single switching element; and
the controller is further configured to passively control deposition of the material onto the cathode by activating the single switching element corresponding with each one of the at least one first deposition anode.
11 . The system according to claim 9 , wherein:
the corresponding deposition control circuit comprises two switching elements and a capacitor; and
the controller is further configured to actively control deposition of the material onto the cathode by activating a first one of the two switching elements corresponding with each one of the at least one first deposition anode, to store electrical energy in the capacitor corresponding with each one of the at least first deposition anode, and activating a second one of the two switching elements corresponding with each one of the at least one first deposition anode, to flow the electrical energy from the capacitor, corresponding with each one of the at least first deposition anode, to the corresponding one of the at least first deposition anode.