Pressure-equalized ink transport system for acoustic ink printers

In an acoustic ink printer having a plurality of ejectors aligned in an axis, each ejector associated with a free surface of liquid ink, said ejector radiating acoustic pressure upon said free surface to eject individual ink droplets on demand, a system for transporting ink under flow constantly to said free surfaces comprising:

• an input manifold parallel to said ejector axis for supplying ink to said ejectors, said input manifold having a first end and a second end opposite said first end, said first end connected to a first liquid ink source at a first predetermined pressure;
• an output manifold parallel to said ejector axis for removing ink from said ejectors, said output manifold having a first end and a second end opposite said first end, said first end adjacent said input manifold first end and connected to a second liquid ink source at a second predetermined pressure, equal in magnitude but opposite in sign to said first predetermined pressure;
• and
• a transverse conduit coupled to at least one of said ejectors and connected to said input manifold and to said output manifold, said transverse conduit having at least one opening defining said free surface associated with said ejector;
• said input manifold having a fluidic resistance defined between said first end and said transverse conduit, said output manifold having a fluidic resistance defined between said first end, said transverse conduit having input and output fluidic resistances, said input fluidic resistance defined between said input manifold and said opening, said output fluidic resistance defined between said opening and said output manifold, the sum of said input manifold fluidic resistance and said transverse conduit input fluidic resistance being equal to the sum of said output manifold fluidic resistance and said transverse conduit output fluidic resistance;
• whereby hydrostatic gauge pressure at each free surface associated with each ejector is substantially equal and zero.

In an acoustic ink printer having a plurality of ejectors aligned in an array of rows and columns, each ejector associated with a free surface of liquid ink, said ejector radiating acoustic pressure upon said free surface to eject individual ink droplets on demand, a system for transporting ink under flow constantly to said free surfaces comprising:

• a primary input manifold parallel to said ejector rows, said manifold having a first end connected to a first ink supply source at a first predetermined pressure and having a plurality of openings, each opening corresponding to one of said ejector columns, said manifold having a predetermined fluidic resistance between each of two adjacent openings;
• a plurality of secondary input manifolds, each input manifold associated with one of said ejector columns and parallel thereto, said input manifold having a first end connected to said primary input manifold opening associated with said ejector column, said input manifold having a plurality of openings corresponding to one ejector in said ejector column, said input manifold having a predetermined fluidic resistance between each of two adjacent openings;
• a primary output manifold parallel to said ejector rows, said manifold having a first end adjacent said primary input manifold first end connected to a second ink supply source at a second predetermined pressure equal in magnitude but opposite in sign to said first predetermined pressure, said primary input manifold having a plurality of openings, each opening corresponding to one of said ejector columns, said manifold having a predetermined fluidic resistance between each two adjacent openings, each fluidic resistance between said two adjacent primary output manifold openings being equal to said fluidic resistance between said two primary input manifold openings corresponding to said two adjacent primary output manifold openings;
• a plurality of secondary output manifolds, each output manifold associated with one of said ejector columns and parallel thereto, said output manifold having a first end adjacent said first end of said secondary output manifold associated with said one ejector column, said secondary output manifold first end connected to said primary output manifold opening associated with said ejector column, said output manifold having a plurality of openings corresponding to one ejector in said ejector column, said output manifold having a plurality of predetermined fluidic resistances between two adjacent openings, each fluidic resistance between said two adjacent secondary output manifold openings being equal to said fluidic resistance between said two secondary input manifold openings corresponding to said two adjacent secondary output manifold openings;
• and
• a plurality of transverse conduits, each transverse conduit coupled to one of said ejectors and connected to said secondary input manifold opening and to said secondary output manifold opening corresponding to said ejector, said transverse conduit having an opening defining said free surface associated with said ejector, said conduit having a predetermined input fluidic resistance between said input manifold opening and said transverse conduit opening, and a predetermined output fluidic resistance between said conduit opening and said output manifold opening, said input and output fluidic resistances being equal to each other;
• whereby hydrostatic gauge pressure at the surface of each free surface is substantially equal and zero.

In an acoustic ink printer having a plurality of ejectors aligned in an array of rows and columns, each ejector associated with a free surface of liquid ink, said ejector radiating acoustic pressure upon said free surface to eject individual ink droplets on demand, a system for transporting ink under flow constantly to said free surfaces comprising:

• a primary input manifold parallel to said ejector rows, said manifold having a first end connected to a first ink supply source at a first predetermined pressure and having a plurality of openings, each opening corresponding to one of said ejector columns, said manifold having a predetermined fluidic resistance between each of two adjacent openings;
• a plurality of secondary input manifolds, each input manifold associated with one of said ejector columns and parallel thereto, said input manifold having a first end and a second end opposite said first end, said first end connected to said primary input manifold opening associated with said ejector column;
• a primary output manifold parallel to said ejector rows, said manifold having a first end adjacent said first input manifold first end connected to a second ink supply source at a second predetermined pressure equal in magnitude but opposite in sign to said first predetermined pressure, said primary output manifold having a plurality of openings, each opening corresponding to one of said ejector columns, said manifold having a predetermined fluidic resistance between each of two adjacent openings, each fluidic resistance between said two adjacent primary output manifold openings being equal to said fluidic resistance between said two primary input manifold openings corresponding to said two adjacent primary output manifold openings;
• a plurality of secondary output manifolds, each output manifold associated with one of said ejector columns and parallel thereto, said output manifold having a first end and a second end opposite said first end, said first end adjacent said first end of said secondary input manifold associated with said ejector column, said secondary output manifold first end connected to said primary output manifold opening associated with said ejector column;
• and
• a transverse conduit coupled to at least one of said ejectors in said ejector column and connected to said secondary input manifold and to said secondary output manifold associated with said ejector column, said transverse conduit having at least one opening defining said free surface associated with said ejector;
• said secondary input manifold having a fluidic resistance defined between said first end and said transverse conduit, said secondary output manifold having a fluidic resistance defined between said first end, said transverse conduit having input and output fluidic resistances, said input fluidic resistance defined between said input manifold and said opening, said output fluidic resistance defined between opening and said output manifold, the sum of said input manifold fluidic resistance and said transverse conduit input fluidic resistance being equal to the sum of said output manifold fluidic resistance and said transverse conduit output fluidic resistance;
• whereby hydrostatic gauge pressure at the surface of each free surface is substantially equal and zero.