Drop-on-demand ink jet print head

Claim 2

An ink jet print head as claimed in Claim 1 wherein the ink pressure chambers are of a substantially equal transverse cress-sectional dimension in all directions.

Claim 3

An ink jet print head as claimed in Claim 1 or Claim 2 wherein the ink pressure chambers are of a circular cross section.

Claim 4

An ink jet print head as claimed in any one of Claims 1 to 3 wherein the ink pressure chambers are arranged in a plurality of parallel adjacent rows.

Claim 5

An ink jet print head as claimed in any preceding claim wherein the ink pressure chambers in a first row thereof are disposed in staggered relation with respect to the ink pressure chambers in a second row thereof.

Claim 6

An ink jet print head as claimed in any preceding claim wherein there are at least four parallel rows of ink pressure chambers.

Claim 7

An ink jet print head as claimed in Claim 6 wherein there are at least four parallel rows of ink pressure chambers, each row having at least four such ink pressure chambers.

Claim 8

An ink jet print head as claimed in any preceding claim wherein the ink pressure chambers have centers arranged in an hexagonal grid.

Claim 9

An ink jet print head as claimed in Claim 8 wherein the hexagonal grid is comprised of regular hexagons.

Claim 10

An ink jet print head as claimed in any preceding claim wherein the centers of the ink pressure chambers are in a common plane.

Claim 11

An ink jet print head as claimed in any preceding claim wherein the passageway means connecting each of said nozzles to an associated outlet are each of substantially the same length and cross-sectional dimension.

Claim 12

An ink jet print head as claimed in any preceding claim wherein each of said passageway means has a major offset channel portion extending in a plane parallel to the plane of the second plate.

Claim 13

An ink jet print head as claimed in any preceding claim wherein each of said nozzles has a central axis extending normal to the plane of the second plate and which intersects the second plate at a location offset from the ink pressure chambers.

Claim 14

An ink jet print head as claimed in any preceding claim in which each ink inlet is substantially larger in cross-sectional dimension than the associated nozzle, the plurality of plates defining at least one ink supply manifold and plural ink supply channel means each coupling the ink supply manifold to an ink inlet of a respective ink pressure chamber. The ink supply channel means and manifold being sized to provide a means for the acoustic damping of pressure pulses from the pressure chambers to reduce acoustic cross-talk between the ink pressure chambers in use of the print head while still providing sufficient ink for ink jet operation at the highest ink jet operating rate.

Claim 15

An ink jet print head as claimed in any preceding claim wherein the plurality of plates defines a purging outlet channel means from the passageway means adjacent the nozzle and through the plates to the exterior of the ink jet print head.

Claim 16

An ink jet print head as claimed in any preceding claim wherein the ink inlets are transversely spaced across the ink pressure chambers from the ink outlets.

Claim 17

An ink jet print head as claimed in any preceding claim and including at least one ink supply manifold means for receiving ink from the ink supply, the ink supply manifold means being connected to plural ink inlets, the ink pressure chambers being arranged in an array with an outer boundary and at a different depth with in the ink jet print head than the depth or depths of the ink pressure chambers.

Claim 18

An ink jet print head for receiving ink from an ink supply and for ejecting drops of ink toward a print medium, the print head comprising a plurality of plates (60, 62, 64, 66, 68, 70, 72, 74, 76, 78) which are held together to form the ink jet print head (10), a first (78) of such plates including plural proximately disposed nozzles (14) therein through which ink drops are ejected, a second (62) of such plates defining a plurality of generally planar ink pressure chambers (22), the ink pressure chambers (22) each being of a transverse circular cross-section with a geometric center, the ink pressure chambers (22) being arranged with their centers positioned in at least four parallel rows, the centers of the ink pressure chambers (22) in one row being offset or staggered from the centers of the ink pressure chambers (22) in an adjacent row, each of said ink pressure chambers (22) having an ink inlet (20) connected to an ink supply and having an outlet (24) for directing ink toward an associated one of said nozzles (14) in the first plate (78), the plurality of plates including at least one passageway-defining plate (64, 66, 68, 70, 72, 74) having passageway means (26) connecting each of said nozzles (14) with an associated one of said outlets (24), the passageway means (64, 66, 68, 70, 72, 74) each being of substantially the same length and cross sectional dimensions, a third one (60) of said plurality of plates being contiguous with the second plate (62) and including driver means (36) for displacing ink contained in each of said ink pressure chambers (22) in use of the print head in a printer to eject ink droplets from each of said nozzles (14), each of said nozzles (14) having a central axis extending normal to the plane of the second plate (62) and intersecting the second plate (62) at a location offset from the ink pressure chambers (22), each ink inlet (20) being larger in cross-sectional dimension than the associated nozzle (14), the plates (64, 66, 68, 70, 72, 74, 76, 78) defining at least one ink manifold means (16) for receiving ink from an ink supply and plural ink supply channel means (18) communicating from the ink supply manifold means (16) to respective ink inlets (20) of the ink pressure chambers (22), the ink supply channel means (18) and manifold means (16) together being sized to provide damping of pressure pulses from pressure chambers (22) to reduce acoustic cross-talk between the ink chambers (22) while still providing sufficient ink for ink jet operation at the highest ink jet operating rate, and each of the ink supply channel means (18) being positioned in a plane between the ink pressure chambers (22) and nozzles (14).

Claim 19

An ink jet print head as claimed in Claim 18 wherein each of said passageway means has a major portion extending in a plane parallel to the plane of the second plate.

Claim 20

A drop-on-demand ink jet print head for receiving ink from an ink supply and for ejecting drops of ink toward a print medium, the print head comprising a body (10) defining at least one row of plural proximately disposed nozzles (14) through which ink drops are ejected, the body (10) also defining a plurality of generally planar ink pressure chambers (22) each having an ink inlet (20) for receiving ink from an ink supply and an ink outlet (24), plural passageway means (26) defined by said body (10) and each coupling the ink outlet (24) of an associated ink pressure chamber (22) to an associated nozzle (14), each nozzle (14) having a central axis normal to the plane of the associated ink pressure chamber (22) and intersecting the plane of the associated ink pressure chamber (22) at a location offset from the associated ink pressure chamber (22), and driver means (36) mounted to the body (10) for displacing ink contained in each of said ink pressure chambers (22) in use of the print head (10) in a printer to eject ink droplets from each of said nozzles (14).

Claim 21

An ink jet print head as claimed in Claim 20 wherein the body is composed of plural plates.

Claim 22

An ink jet print head as claimed in Claim 20 or Claim 21 wherein the ink pressure chambers are generally co-planar.

Claim 23

An ink jet print head as claimed in any one of Claims 20 to 22 wherein the ink pressure chambers are arranged in plural parallel rows, each of the ink pressure chambers having a geometric center, the centers of the ink pressure chambers in one row being staggered from the centers of the ink pressure chambers in an adjacent row.

Claim 24

An ink jet print head as claimed in Claim 23 wherein there are at least four such rows of ink pressure chambers.

Claim 25

An ink jet print head as claimed in any one of Claims 20 to 24 wherein the ink pressure chambers are of circular transverse cross-section.

Claim 26

An ink jet print head as claimed in any one of Claims 18 to 25 wherein each of said passageway means extends in a first direction normal to the plane of the second plate for a first distance, has an offset channel portion extending in a second direction in a plane parallel to the plane of the second plate for a second distance and extends in a third direction parallel to the first direction for a third distance to a nozzle, and wherein the second distance is greater than the first and third distances.

Claim 27

An ink jet print head as claimed in any one of Claims 20 to 26 wherein each ink inlet is larger in cross-sectional dimension than the associated nozzle, the body of said head defining at least one ink supply manifold means and plural ink supply channel means each coupling the ink supply manifold means to an ink inlet of a respective ink pressure chamber, the ink supply channel means and manifold means being sized to provide a means for acoustic isolation one from another of the ink pressure chambers coupled to the manifold.

Claim 28

An ink jet print head as claimed in any one of Claims 20 to 27 wherein the body defines a purging outlet channel means from the passageway means adjacent the nozzle and through the body to the exterior of the ink jet print head.

Claim 29

A drop-on-demand ink jet print head for receiving ink from an ink supply and for ejecting drops of ink toward a print medium, the print head comprising a body (10) defining plural proximately disposed nozzles (14) through which ink drops are ejected, the body also defining a plurality of generally planar ink pressure chambers (22) each having an ink inlet (20) and an ink outlet (24), plural passageway means (26) defined by said body (10) and each coupling the ink outlet (24) of an associated ink pressure chamber (22) to an associated nozzle (14), each nozzle (14) having a central axis normal the plane of the associated ink pressure chamber (22), the body (10) defining at least one ink manifold (16) for receiving ink from an ink supply and plural ink supply channel means (18) communicating from the ink supply manifold (16) to respective ink inlets (20) of the ink pressure chambers, the ink supply channel means (18) and manifold (16) together being sized to provide a means for damping of pressure pulses from pressure chambers (22) to reduce acoustic cross-talk between the ink chambers while still providing sufficient ink for ink jet operation at the highest ink jet operating rate, each of the ink supply channel means (18) being positions in a plane between the associated ink pressure chamber (22) and nozzle (14), and the print head (10) including driver means (36) mounted to the body for displacing ink in each of the ink pressure chambers (22) in use of the print head (10) in a printer to eject ink droplets from each of said nozzles (14).

Claim 30

An ink jet print head as claimed in Claim 29 wherein each of the ink supply channel means is of the same length and cross-sectional dimension.

Claim 31

An ink jet print head as claimed in Claim 29 or Claim 30 wherein each of the ink supply channel means is of a cross-sectional dimension which is substantially greater than the cross-sectional dimension of the nozzles.

Claim 32

An ink jet print head as claimed in any of Claims 29 to 31 wherein there are at least four rows of such ink pressure chambers, with at least four such ink pressure chambers being in each row.

Claim 33

An ink jet print head as claimed in any one of Claims 29 to 32 wherein the body is formed of plural plates, at least one plate defining the ink pressure chambers, at least one plate defining the passageway means, at least one plate defining the nozzles, and at least one plate defining the ink manifold and ink supply passageways.

Claim 34

An ink jet print head as claimed in any one of Claims 29 to 33 wherein each of the passageway means is of the same cross-sectional dimension and length.

Claim 35

An ink jet print head as claimed in any one of Claims 29 to 34 wherein each of the passageway means is of the same acoustic resistance.

Claim 36

An ink jet print head as claimed in Claim 30 wherein each of the passageway means is of the same cross-sectional dimension and length.

Claim 37

An ink jet print head for receiving ink from an ink supply and for ejecting drops of ink toward print medium, the print head comprising a body (10) defining at least N rows of plural generally planar ink pressure chambers (22) each having a geometric center, the center-to-center spacing of the ink pressure chambers (22) of each row being a distance X, each ink pressure chamber (22) having an ink inlet (20) and an ink outlet (24), and being spaced from adjacent ink pressure chambers (22) by substantially no more of the body (10) than is required to define separated ink pressure chambers (22), the body (10) defining plural nozzles (14) through which ink drops are ejected in use of the print head in a printer, the nozzles (14) having central axes normal to the plane of the ink pressure chambers (22), plural passageways (26) defined by said body (10) and coupling the ink outlet (24) of an associated ink pressure chamber (22) to an associated nozzle (14), and the nozzles (14) each having a geometric center and, being arranged in a row with their center-to-center spacing being approximately no greater than a X divided by N.

Claim 38

An ink jet print head as claimed in Claim 37 wherein N is equal to at least four, there being at least four ink pressure chambers (22) in each row.

Claim 39

An ink jet printer as claimed in Claim 37 or Claim 38 wherein the body is formed of plural plates, the ink pressure chambers having been spaced apart substantially no more of the body than is required for bonding of the plates between the ink pressure chambers.

Claim 40

An ink jet print head for receiving ink from an ink supply and for ejecting drops of ink toward print medium comrising a body (10) defining a generally planar ink pressure chamber (22) having an ink inlet (20) for receiving ink from an ink supply and an ink outlet (24), the body (10) defining a nozzle (14) through which ink drops are ejected, the body (10) defining a passageway (26) coupling the ink outlet (24) to the nozzle (14), the passageway (26) having a major portion comprising an offset channel (71) extending in a plane parallel to the plane of the ink chamber (22), the nozzle (14) having a central axis which is normal to the plane of the ink pressure chamber (22) and which is offset from the ink pressure chamber (22) and driver means (36) mounted to the body (10) for displacing ink in the chamber (22) to thereby result in the ejection of ink from the ink chamber (22).

Claim 41

An ink jet print head as claimed in Claim 40 wherein the ink inlet enters the ink pressure chamber at a location in the plane between the ink chamber and nozzle and in which the ink outlets exits from the ink pressure chamber at a location in a plane between the ink pressure chamber and nozzle and at a location which is closer to the nozzle than the ink inlet.

Claim 42

An ink jet print head as claimed in Claim 40 or Claim 41 wherein the ink inlet is positioned transversely across the ink pressure chamber from the ink outlet.

Claim 43

An ink jet print head as claimed in any one of Claims 40 to 42 wherein the ink outlet is fluidically closer to the nozzle than the ink inlet.

Claim 44

An ink jet print head as claimed in any one of Claims 40 to 43 wherein the body is formed of plural generally planar plates which define the ink inlet, the ink pressure chamber, the ink outlet, the passage and nozzle.

Claim 45

An ink jet print head as claimed in Claim 44 and having a nozzle plate which defines the nozzle and a guard plate overlying the nozzle plate.

Claim 46

A drop-on-demand ink jet print head with multiple nozzles (14) for delivering drops of colored ink to print medium, the nozzles (14) being arranged in at least one row, ink supply means for supplying ink of at least two colors to the nozzles (14), the ink supply means comprising means for supplying the nozzles (14) such that adjacent nozzles in the row are each supplied with a different color of ink.

Claim 47

An ink jet printer comprising a drop-on-demand ink jet print head as claimed in any preceding claim.