Patent Publication Number: US-9849682-B2

Title: Ink port adapter for inkjet head

Description:
RELATED APPLICATIONS 
     This non-provisional patent application is a continuation of U.S. patent application Ser. No. 15/058,093 filed on Mar. 1, 2016, which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The following disclosure relates to the field of printing, and in particular, to inkjet heads used in printing. 
     BACKGROUND 
     Inkjet printing is a type of printing that propels drops of ink (also referred to as droplets) onto a medium, such as paper, a substrate for 3D printing, etc. The core of an inkjet printer includes one or more print heads (referred to herein as inkjet heads) having multiple ink channels arranged in parallel to discharge droplets of ink. A typical ink channel includes a nozzle, a chamber, and a mechanism for ejecting the ink from the chamber and through the nozzle, which is typically a piezoelectric actuator connected to a diaphragm. To discharge a droplet from an ink channel, a drive circuit provides a drive waveform to the piezoelectric actuator of that ink channel that includes a jetting pulse. In response to the jetting pulse, the piezoelectric actuator generates pressure oscillations inside of the ink channel to push the droplet out of the nozzle. The drive waveforms provided to individual piezoelectric actuators control how droplets are ejected from each of the ink channels. 
     Inkjet heads are typically configured as single-color, two-color, or four-color heads. Users select the type of inkjet head based on their printing needs. For example, if a user has a need for both two-color and four-color printing, then they will select both a two-color and a four-color inkjet head. Users may therefore need to purchase multiple types of inkjet heads based their printing needs. 
     SUMMARY 
     Embodiments described herein include adapters for multi-color inkjet heads that reduce the number of colors that are printed with the inkjet heads. For example, an adapter may allow a four-color inkjet head to print in two-color or single-color. An adapter may allow a two-color inkjet head to print in single-color. Therefore, use of adapters as described herein advantageously gives users flexibility in how multi-color inkjet heads are used for printing. 
     One embodiment is an apparatus including an ink port adapter. The ink port adapter comprises a body having a first surface and a second surface, two hose fittings that extend from the first surface of the body for connecting to hoses, four openings on the second surface of the body that align with four ink ports on one end of a four-color inkjet head, a first ink path through the body that connects a first one of the hose fittings to a first one of the openings and to a second one of the openings, and a second ink path through the body that connects a second one of the hose fittings to a third one of the openings and to a fourth one of the openings. This type of ink port adaptor is for converting a four-color inkjet head to a two-color inkjet head. 
     In another embodiment, the apparatus includes o-rings to be compressed between the four openings of the ink port adapter and the four ink ports of the inkjet head. 
     In another embodiment, the o-rings are seated in recesses in the four ink ports of the inkjet head. 
     In another embodiment, the apparatus further includes fastening members configured to attach the ink port adapter to the four-color inkjet head. 
     In another embodiment, the ink port adapter further includes a plurality of connecting holes through the body to align with threaded holes on the inkjet head. The fastening members are inserted through the connecting holes of the ink port adapter to screw into the threaded holes on the inkjet head. 
     In another embodiment, a first one of the hose fittings connects with a first hose that supplies a first color of ink, and a second one of the hose fittings connects with a second hose that supplies a second color of ink. 
     Another embodiment is an apparatus that includes an ink port adapter. The ink port adapter includes a body having a first surface and a second surface, a hose fitting that extends from the first surface of the body for connecting to a hose, four openings on the second surface of the body that align with four ink ports on one end of a four-color inkjet head, and an ink path through the body that connects the hose fitting to each of the openings. This type of ink port adaptor is for converting a four-color inkjet head to a single-color inkjet head. 
     Another embodiment is an apparatus that includes an ink port adapter. The ink port adapter includes a body having a first surface and a second surface, a hose fitting that extends from the first surface of the body for connecting to a hose, two openings on the second surface of the body that align with two ink ports on one end of a two-color inkjet head, and an ink path through the body that connects the hose fitting to each of the openings. This type of ink port adaptor is for converting a two-color inkjet head to a single-color inkjet head. 
     The above summary provides a basic understanding of some aspects of the specification. This summary is not an extensive overview of the specification. It is intended to neither identify key or critical elements of the specification nor delineate any scope particular embodiments of the specification, or any scope of the claims. Its sole purpose is to present some concepts of the specification in a simplified form as a prelude to the more detailed description that is presented later. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Some embodiments of the present disclosure are now described, by way of example only, and with reference to the accompanying drawings. The same reference number represents the same element or the same type of element on all drawings. 
         FIG. 1  illustrates an inkjet head. 
         FIG. 2  illustrates an I/O side of an inkjet head in one example. 
         FIG. 3  is a schematic view of an inkjet head. 
         FIG. 4  illustrates an I/O side of an inkjet head in another example. 
         FIG. 5  is a schematic view of an inkjet head. 
         FIG. 6  illustrates one end of a four-color inkjet head in an exemplary embodiment. 
         FIG. 7  is an isometric view of an ink port adapter in an exemplary embodiment. 
         FIGS. 8A-8B  illustrate top and bottom views of an ink port adapter in an exemplary embodiment. 
         FIGS. 9-10  are cross-sectional views of an ink port adapter being attached to an inkjet head in an exemplary embodiment. 
         FIG. 11  is an isometric view of an ink port adapter in an exemplary embodiment. 
         FIGS. 12A-12B  illustrate top and bottom views of an ink port adapter in an exemplary embodiment. 
         FIGS. 13-14  are cross-sectional views of an ink port adapter being attached to an inkjet head in an exemplary embodiment. 
         FIG. 15  illustrates one end of a two-color inkjet head in an exemplary embodiment. 
         FIG. 16  is an isometric view of an ink port adapter in an exemplary embodiment. 
         FIGS. 17A-17B  illustrate top and bottom views of an ink port adapter in an exemplary embodiment. 
         FIG. 18  is a cross-sectional view of an ink port adapter being attached to an inkjet head in an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The figures and the following description illustrate specific exemplary embodiments. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the embodiments and are included within the scope of the embodiments. Furthermore, any examples described herein are intended to aid in understanding the principles of the embodiments, and are to be construed as being without limitation to such specifically recited examples and conditions. As a result, the inventive concept(s) is not limited to the specific embodiments or examples described below, but by the claims and their equivalents. 
       FIG. 1  illustrates an inkjet head  100 . Although not visible in  FIG. 1 , inkjet head  100  includes a nozzle surface  102  with one or more rows of nozzles that jet or eject droplets of liquid material, such as ink (e.g., water, solvent, oil, or UV-curable). Opposite the nozzle surface  102  is the side of inkjet head  100  used for input/output (I/O) of ink, electronic signals, etc. This side of inkjet head  100  is referred to as the I/O side  104 . I/O side  104  includes electronics  106  that connect to a data source through cabling  108 . Electronics  106  control how the nozzles of inkjet head  100  jet droplets of ink. As will be described in more detail below, I/O side  104  also includes ink ports for transferring ink into or out of inkjet head  100 . Although the term “ink” is used herein, inkjet head  100  is capable of dispersing different types of liquid material used for printing. 
       FIG. 2  illustrates the I/O side  104  of inkjet head  100  in one example. In the example shown in  FIG. 2 , inkjet head  100  is a four-color head. I/O side  104  has two ends  202 - 203  that are separated by electrical connectors  206 - 207 . Each end  202 - 203  includes four ink ports. For example, end  202  includes ink ports  210 ,  212 ,  214 , and  216 . End  203  includes ink ports  211 ,  213 ,  215 , and  217 . An ink port represents an opening for receiving ink from an ink supply, or transferring ink out of inkjet head  100 . Ink ports  210 - 217  provide a pathway to ink manifolds within inkjet head  100 . An ink manifold is a conduit within an inkjet head for providing ink to a plurality of ink channels/nozzles for jetting.  FIG. 3  is a schematic view of inkjet head  100  as shown in  FIG. 2 . Ink ports  210 - 211  provide pathways to an ink manifold  310  for a first color. Ink ports  212 - 213  provide pathways to an ink manifold  312  for a second color. Ink ports  214 - 215  provide pathways to an ink manifold  314  for a third color. Ink ports  216 - 217  provide pathways to an ink manifold  316  for a fourth color. Each of the ink manifolds  310 - 316  connects to a row of nozzles  320 - 322 , and provides ink to the nozzles  320 - 322  for jetting. 
       FIG. 4  illustrates the I/O side  104  of inkjet head  100  in another example. In the example shown in  FIG. 4 , inkjet head  100  is a two-color head. I/O side  104  has two ends  402 - 403  that are separated by electrical connectors  406 - 407 . Each end  402 - 403  includes two ink ports. For example, end  402  includes ink ports  410  and  412 . End  403  includes ink ports  411  and  413 .  FIG. 5  is a schematic view of inkjet head  100  as shown in  FIG. 4 . Ink ports  410 - 411  provide pathways to ink manifolds  510  and  512  for a first color. Ink ports  412 - 413  provide pathways to ink manifolds  514  and  516  for a second color. Each of the ink manifolds  510 - 516  connects to a row of nozzles  520 - 522 , and provides ink to the nozzles  520 - 522  for jetting. 
     When using multi-color inkjet heads as described above, a user may want to reduce the number of colors that are used with an inkjet head. For example, if a user has a four-color inkjet head, he/she may want to operate the four-color inkjet head as a two-color or a single-color inkjet head. If a user has a two-color inkjet head, he/she may want to operate the two-color inkjet head as a single-color inkjet head. To accommodate this, ink port adapters are described herein that allow multi-color inkjet heads to be used with a reduced number of colors. For example, an ink port adapter may convert a four-color inkjet head for use as a two-color or a single-color inkjet head. An ink port adapter may convert a two-color inkjet head for use as a single-color inkjet head. Descriptions of the ink port adapters are described below. 
       FIG. 6  illustrates one end of a four-color inkjet head  600  in an exemplary embodiment. End  602  is separated from the other end (not shown) of inkjet head  600  by electrical connectors  606 - 607 . End  602  includes four ink ports  610 - 613 , which comprise openings for transferring ink to/from inkjet head  600 . Although not visible in  FIG. 6 , each ink port  610 - 613  connects to an ink manifold within inkjet head  600 . In this embodiment, ink ports  610 - 613  may each include a recess  620 - 623  for receiving an o-ring, which is described further below. End  602  also includes threaded holes  630 - 632  for receiving a fastening member, such as a screw or bolt. 
     Although inkjet head  600  is a four-color inkjet head, it may be used as a two-color inkjet head with the use of an ink port adapter as described herein.  FIG. 7  is an isometric view of an ink port adapter  700  in an exemplary embodiment. Ink port adapter  700  is an apparatus configured to convert a four-color inkjet head to a two-color inkjet head. Ink port adapter  700  includes a body  701  having a top surface  702  and a bottom surface  703 . Although the terms “top” and “bottom” are used herein, it is merely to distinguish the surfaces  702 - 703  in  FIG. 7 . The body  701  of ink port adapter  700  may be made from plastic, Teflon®, or any other desired material. Top surface  702  includes hose fittings  710 - 711 , which are hollow cylindrical features that extend from top surface  702  to act as a connection point for a hose, such as from an ink reservoir. A hose is able to slide over each of hose fittings  710 - 711 . Although not shown in  FIG. 7 , hose fittings  710 - 711  may be barbed or have other surface features for securing a hose. Ink port adapter  700  also includes a plurality of connecting holes  720 - 722  that pass from top surface  702  to bottom surface  703  to align with threaded holes  630 - 632  on inkjet head  600 . Fastening members  730 , such as screws or bolts, are inserted through connecting holes  720 - 722 , and screw into threaded holes  630 - 632  to secure ink port adapter  700  to inkjet head  600 . 
       FIGS. 8A-8B  illustrate top and bottom views of ink port adapter  700  in an exemplary embodiment. The top view  801  in  FIG. 8A  illustrates hose fittings  710 - 711  and connecting holes  720 - 722  on top surface  702  of ink port adapter  700 . The bottom view  802  in  FIG. 8B  illustrates four openings  810 - 813  on bottom surface  703  of ink port adapter  700 , and connecting holes  720 - 722 . As is evident from top view  801  and bottom view  802 , connecting holes  720 - 722  pass through the body  701  of ink port adapter  700  from top surface  702  to bottom surface  703 . Openings  810 - 813  are configured to align with the four ink ports  610 - 613  of inkjet head  600  (see  FIG. 6 ). Although not visible in  FIGS. 8A-8B , an ink path passes through body  701  that connects hose fitting  710  to openings  810 - 811 . Another separate ink path passes through body  701  that connects hose fitting  711  to openings  812 - 813 . An ink path is a hollow channel through body  701  that allows ink to flow, such as between a hose fitting  710 - 711  on top surface  702  and multiple openings  810 - 813  on bottom surface  703 . 
       FIGS. 9-10  are cross-sectional views of ink port adapter  700  being attached to inkjet head  600  in an exemplary embodiment.  FIG. 9  is a cross-section along line  9 - 9  of  FIG. 6 , and  FIG. 10  is a cross-section along line  10 - 10  of  FIG. 6 . Ink ports  610 - 613  of inkjet head  600  include recesses  620 - 623 , respectively. O-rings  902  may be inserted into recesses  620 - 623 . When compressed, o-rings  902  provide a seal between ink port adapter  700  and inkjet head  600 . Openings  810 - 813  on ink port adapter  700  align with ink ports  610 - 613  to provide a fluid connection. An ink path  910  connects hose fitting  710  to openings  810 - 811 . Therefore, ink flowing from a hose into hose fitting  710  will travel through adapter  700  to both opening  810  and opening  811 . Another ink path  911  connects hose fitting  711  to openings  812 - 813 . Therefore, ink flowing from a hose into hose fitting  711  will travel through adapter  700  to both opening  812  and opening  813 . 
     When in use, ink port adapter  700  is placed onto end  602  of inkjet head  600 , and is fastened to inkjet head  600  with fastening members  730 . In  FIG. 6 , the other end (not shown) of inkjet head  600  will have a similar configuration with ink ports, and an ink port adapter may be attached to the other end of inkjet head  600  in a similar manner. Hoses are connected to hose fittings  710 - 711 . The hoses may be attached to ink reservoirs of different colors to supply two colors of ink to inkjet head  600 . When one color of ink is supplied through the hose connected to hose fitting  710 , the ink will flow through hose fitting  710 , through ink path  910 , and out openings  810 - 811  into ink ports  610 - 611  of inkjet head  600 . When another color of ink is supplied through the hose connected to hose fitting  711 , the ink will flow through hose fitting  711 , through ink path  911 , and out openings  812 - 813  into ink ports  612 - 613  of inkjet head  600 . Thus, even though inkjet head  600  has four ink ports  610 - 613  on each end for receiving four colors of ink, ink port adapter  700  allows inkjet head  600  to operate while receiving only two colors of ink. 
     Although o-rings  902  are illustrated in  FIGS. 9-10 , other types of sealing mechanisms may be used between ink port adapter  700  and inkjet head  600 . For example, a gasket may be used as a sealing mechanism in another embodiment. When a gasket is used, recesses  620 - 623  may not be needed in ink ports  610 - 613 . 
     Inkjet head  600  (see  FIG. 6 ) may also be used as a single-color inkjet head with the use of another ink port adapter.  FIG. 11  is an isometric view of an ink port adapter  1100  in an exemplary embodiment. Ink port adapter  1100  is an apparatus configured to convert a four-color inkjet head to a single-color inkjet head. Ink port adapter  1100  includes a body  1101  having a top surface  1102  and a bottom surface  1103 . Top surface  1102  includes a hose fitting  1110 . Ink port adapter  1100  also includes a plurality of connecting holes  1120 - 1122  that pass from top surface  1102  to bottom surface  1103  to align with threaded holes  630 - 632  on inkjet head  600 . Fastening members  1130  are inserted through connecting holes  1120 - 1122 , and screw into threaded holes  630 - 632  to secure ink port adapter  1100  to inkjet head  600 . 
       FIGS. 12A-12B  illustrate top and bottom views of ink port adapter  1100  in an exemplary embodiment. The top view  1201  in  FIG. 12A  illustrates hose fitting  1110  and connecting holes  1120 - 1122  on top surface  1102  of ink port adapter  1100 . The bottom view  1202  in  FIG. 12B  illustrates four openings  1210 - 1213  on bottom surface  1103  of ink port adapter  1100 , and connecting holes  1120 - 1122 . As is evident from top view  1201  and bottom view  1202 , connecting holes  1120 - 1122  pass through the body  1101  of ink port adapter  1100  from top surface  1102  to bottom surface  1103 . Openings  1210 - 1213  are configured to align with the four ink ports  610 - 613  of inkjet head  600  (see  FIG. 6 ). Although not visible in  FIGS. 12A-12B , an ink path passes through body  1101  that connects hose fitting  1110  to openings  1210 - 1213 . 
       FIGS. 13-14  are cross-sectional views of ink port adapter  1100  being attached to inkjet head  600  in an exemplary embodiment.  FIG. 13  is a cross-section along line  9 - 9  of  FIG. 6 , and  FIG. 14  is a cross-section along line  10 - 10  of  FIG. 6 . Ink ports  610 - 613  of inkjet head  600  include recesses  620 - 623 , respectively. O-rings  902  may be inserted into recesses  620 - 623 . When compressed, o-rings  902  provide a seal between ink port adapter  1100  and inkjet head  600 . Openings  1210 - 1213  on ink port adapter  1100  align with ink ports  610 - 613  to provide a fluid connection. An ink path  1310  connects hose fitting  1110  to openings  1210 - 1213 . Therefore, ink flowing from a hose into hose fitting  1110  will travel through adapter  1100  to each of openings  1210 - 1213 . 
     When in use, ink port adapter  1100  is placed onto end  602  of inkjet head  600 , and is fastened to inkjet head  600  with fastening members  1130 . In  FIG. 6 , the other end (not shown) of inkjet head  600  will have a similar configuration with ink ports, and an ink port adapter may be attached to the other end of inkjet head  600  in a similar manner. A hose is connected to hose fitting  1110 . The hose may be attached to an ink reservoir of a single color to supply one color of ink to inkjet head  600 . When one color of ink is supplied through the hose connected to hose fitting  1110 , the ink will flow through hose fitting  1110 , through ink path  1310 , and out openings  1210 - 1213  into ink ports  610 - 613  of inkjet head  600 . Thus, even though inkjet head  600  has four ink ports on each end for receiving four colors of ink, ink port adapter  1100  allows inkjet head  600  to operate while receiving only one color of ink. 
       FIG. 15  illustrates one end of a two-color inkjet head  1500  in an exemplary embodiment. End  1502  is separated from the other end (not shown) of inkjet head  1500  by electrical connectors  1506 - 1507 . End  1502  includes two ink ports  1510 - 1511 , which comprise openings for transferring ink to/from inkjet head  1500 . Although not visible in  FIG. 15 , each ink port  1510 - 1511  connects to an ink manifold within inkjet head  1500 . In this embodiment, ink ports  1510 - 1511  may each include a recess  1520 - 1521  for receiving an o-ring, which is described further below. End  1502  also includes threaded holes  1530 - 1532  for receiving a fastening member, such as a screw or bolt. 
     Although inkjet head  1500  is a two-color inkjet head, it may be used as a single-color inkjet head with the use of an ink port adapter.  FIG. 16  is an isometric view of an ink port adapter  1600  in an exemplary embodiment. Ink port adapter  1600  is an apparatus configured to convert a two-color inkjet head to a single-color inkjet head. Ink port adapter  1600  includes a body  1601  having a top surface  1602  and a bottom surface  1603 . Top surface  1602  includes a hose fitting  1610 . Ink port adapter  1600  also includes a plurality of connecting holes  1620 - 1622  that pass from top surface  1602  to bottom surface  1603  to align with threaded holes  1530 - 1532  on inkjet head  1500 . Fastening members  1630 , such as screws or bolts, are inserted through connecting holes  1620 - 1622 , and screw into threaded holes  1530 - 1532  to secure ink port adapter  1600  to inkjet head  1500 . 
       FIGS. 17A-17B  illustrate top and bottom views of ink port adapter  1600  in an exemplary embodiment. The top view  1701  in  FIG. 17A  illustrates hose fitting  1610  and connecting holes  1620 - 1622  on top surface  1602  of ink port adapter  1600 . The bottom view  1702  in  FIG. 17B  illustrates two openings  1710 - 1711  on bottom surface  1603  of ink port adapter  1600 , and connecting holes  1620 - 1622 . As is evident from top view  1701  and bottom view  1702 , connecting holes  1620 - 1622  pass through the body  1601  of ink port adapter  1600  from top surface  1602  to bottom surface  1603 . Openings  1710 - 1711  are configured to align with the two ink ports  1510 - 1511  of inkjet head  1500  (see  FIG. 15 ). Although not visible in  FIGS. 17A-17B , an ink path passes through body  1601  that connects hose fitting  1610  to openings  1710 - 1711 . 
       FIG. 18  is a cross-sectional view of ink port adapter  1600  being attached to inkjet head  1500  in an exemplary embodiment.  FIG. 18  is a cross-section along line  18 - 18  of  FIG. 15 . Ink ports  1510 - 1511  of inkjet head  1500  include recesses  1520 - 1521 , respectively. O-rings  902  may be inserted into recesses  1520 - 1521 . When compressed, o-rings  902  provide a seal between ink port adapter  1600  and inkjet head  1500 . Openings  1710 - 1711  on ink port adapter  1600  align with ink ports  1510 - 1511  to provide a fluid connection. An ink path  1810  connects hose fitting  1610  to openings  1710 - 1711 . Therefore, ink flowing from a hose into hose fitting  1610  will travel through adapter  1600  to both opening  1710  and opening  1711 . 
     When in use, ink port adapter  1500  is placed onto end  1502  of inkjet head  1500 , and is fastened to inkjet head  1500  with fastening members  1630 . In  FIG. 15 , the other end (not shown) of inkjet head  1500  will have a similar configuration with ink ports, and an ink port adapter may be attached to the other end of inkjet head  1500  in a similar manner. A hose is connected to hose fitting  1610 . The hose may be attached to an ink reservoir of a single color to supply one color of ink to inkjet head  1500 . When one color of ink is supplied through the hose connected to hose fitting  1610 , the ink will flow through hose fitting  1610 , through ink path  1810 , and out openings  1710 - 1711  into ink ports  1510 - 1511  of inkjet head  1500 . Thus, even though inkjet head  1500  has two ink ports on each end for receiving two colors of ink, ink port adapter  1600  allows inkjet head  1500  to operate while receiving only one color of ink. 
     The ink port adapters described above are able to transform multi-color inkjet heads for use with fewer colors. For example, if an ink port adapter is attached to a four-color inkjet head, then the four-color inkjet head may be used as a two-color or single-color inkjet head. If an ink port adapter is attached to a two-color inkjet head, then the two-color inkjet head may be used as a single-color inkjet head. Therefore, a consumer may not have to buy new inkjet heads for different applications. A consumer may buy a four-color head, and use that four-color head for four-color printing in one application, two-color printing in another application (with an adapter), or single-color printing in yet another application (with an adapter). Use of the ink port adapters described above advantageously gives the consumer flexibility in printing with an individual inkjet head. 
     Although specific embodiments were described herein, the scope of the invention is not limited to those specific embodiments. The scope of the invention is defined by the following claims and any equivalents thereof.