Printing tiles and printhead assemblies for inkjet printers

Abstract

There is a need for large scale processing formats for display manufacturing, and processing formats that are also applicable to the manufacturing of other electronic devices. [Solution] A printing tile for a printer printhead assembly includes a base plate, a printhead, a nozzle plate attached to the printhead, and a plurality of mounting elements. The base plate has an upper surface, a lower surface opposite the upper surface, and a slot extending through the base plate. The printhead has a lower portion inserted into the slot, and the lower portion is provided with a plurality of nozzles for ejecting printing material during a printing operation. The plurality of mounting elements mount the nozzle plate to the base plate while allowing adjustment of the position of the printhead relative to the base plate. The base plate includes first and second adjustable elevation portions below first and second ends of the nozzle plate, respectively, and the first and second adjustable elevation portions allow the positions of the first and second ends of the nozzle plate to be separately adjusted.

Description

[Background technology]

[0001] Industrial inkjet printers are used to apply materials to large substrates to form various devices. The substrates can be hard or soft, thick or thin, and made of a variety of materials. The most typical types of substrates used in this way include substrates made of various types of glass, which are processed to produce electronic displays such as televisions and displays for smartphones.

[0002] Such displays are typically formed by mapping many devices onto a large sheet of glass. Creating multiple devices in a single process allows economies of scale, lowering the unit cost of each individual device. There is a continuing need for large-scale process formats for display manufacturing, as well as process formats that can be adapted to manufacture other electronic devices using other substrates.

[0003] Especially for display devices, while economies of scale are expected to increase, uniformity problems arise as the scale increases. The manufacturing process for display devices can cause visible defects such as lines and patterns on the device, rendering the device unusable. These problems have been largely solved by current commercial printers, but as the scale increases, new uniformity problems always arise.

[0004] In addition, as the substrate size increases and the printing area increases, the printing time naturally becomes longer, so there is also a need to increase the speed of manufacturing each substrate.

[0005] In addition, display devices are constantly trending toward higher resolution, complicating the move to larger sizes of products. Reducing the size of droplets printed on a substrate always comes with the potential for new uniformity problems. The above creates a need to continue to build uniform devices without visible defects while increasing the scale and speed of commercial inkjet printing and increasing the resolution of commercial inkjet printing. Summary of the Invention

[0006] In at least one embodiment, a printing tile for a printer printhead assembly includes a base plate, a printhead, a nozzle plate attached to the printhead, and a number of mounting elements. The base plate has an upper surface, a lower surface opposite the upper surface in a thickness direction of the base plate, and a slot extending through the base plate from the upper surface to the lower surface. The printhead has a lower portion inserted into the slot, and the lower portion is provided with a number of nozzles for ejecting printing material during a printing operation. The number of mounting elements mount the nozzle plate to the base plate while allowing adjustment of the position of the printhead relative to the base plate. The nozzle plate has first and second ends located opposite each other. The base plate includes first and second adjustable lifting members below the first and second ends of the nozzle plate, respectively, for separately adjusting the positions of the first and second ends of the nozzle plate in a thickness direction of the base plate by the lifting members.

[0007] In at least one embodiment, a printing tile for a printhead assembly of a printer includes a base plate, a plurality of printheads, a plurality of nozzle plates attached to correspond to the plurality of printheads, and a plurality of mounting elements for mounting the plurality of nozzle plates to the base plate. The base plate has an upper surface, a lower surface opposite to the upper surface in a thickness direction of the base plate, and a plurality of slots penetrating the base plate from the upper surface to the lower surface. Each of the plurality of printheads has a lower portion inserted into a corresponding one of the plurality of slots, and the lower portion is provided with a plurality of nozzles for ejecting printing material during a printing operation. The plurality of mounting elements include, for each nozzle plate of the plurality of nozzle plates, first and second fastening elements for fastening first and second ends of the nozzle plate, respectively, to the base plate, and a conical screw. A conical surface of the conical screw engages with the first end of the nozzle plate to adjust the position of the first end in a rotational direction. The rotational direction is a rotational direction about an axis located at the second end of the nozzle plate and aligned along the thickness direction of the base plate.

[0008] In at least one embodiment, a printhead assembly for an inkjet printer includes a housing, a feed mechanism supported on an upper portion of the housing, and a plurality of printing tiles removably supported on a lower portion of the housing, each of the plurality of printing tiles including a base plate having a plurality of slots, a plurality of printheads, each printhead having a portion inserted into a corresponding one of the plurality of slots and a plurality of nozzles for ejecting printing material during a printing operation, a plurality of nozzle plates correspondingly mounted to the plurality of printheads, a plurality of mounting elements adjustably fastening the plurality of nozzle plates to the base plate, and a connector set disposed above the plurality of printheads, the connector set including at least one fluid connector fluidically coupled to the plurality of printheads and at least one electrical connector electrically coupled to the plurality of printheads. The feed mechanism includes a corresponding connector set for each of the plurality of printing tiles, the corresponding connector set being coupled to the connector set of the printing tile when the printing tile is removably attached to the feed mechanism from below by the fastening structure and the alignment structure. The alignment structure includes at least one alignment pin on one of the feed mechanism and the print tile and at least one alignment hole on the other of the feed mechanism and the print tile, the at least one alignment pin being aligned and inserted into the at least one alignment hole. [Brief description of the drawings]

[0009] Aspects of the present disclosure will be best understood from the following detailed description when read in conjunction with the accompanying drawings, in which: In accordance with standard practice in the industry, various features have not been drawn to scale, and in fact, dimensions of various features may be arbitrarily increased or decreased for illustrative purposes.

[0010] [Figure 1] 1 is a top perspective view of an inkjet printer according to an embodiment;

[0011] [Diagram 2]FIG. 2 is a bottom perspective view of a printhead assembly according to an embodiment.

[0012] [Diagram 3] FIG. 2 is an elevated perspective view of a printing tile of a printhead assembly according to one embodiment.

[0013] [Figure 4A] FIG. 2 is a top perspective view, partially exploded, of a printhead assembly according to one embodiment.

[0014] [Figure 4B] FIG. 4B is a bottom perspective view, partially exploded, of the printhead assembly of FIG. 4A according to one embodiment.

[0015] [Figure 5A] FIG. 2 is a partial top perspective view of the bottom of a printing tile showing a base plate, nozzle plate, and printhead according to one embodiment.

[0016] [Figure 5B] FIG. 5B illustrates a top view of a portion of the printhead, nozzle plate, and base plate of FIG. 5A in accordance with one embodiment.

[0017] [Figure 5C] FIG. 5B is a schematic cross-sectional view taken along line II of FIG. 5A, according to one embodiment.

[0018] [Figure 5D] FIG. 5B illustrates a top view of the printhead, nozzle plate, and base plate of FIG. 5A with spacers interposed, according to one embodiment.

[0019] [Figure 5E] FIG. 2 is a top perspective view of a spacer according to one embodiment.

[0020] [Figure 6A] FIG. 1 is a side view of a conical screw according to one embodiment.

[0021] [Figure 6B] FIG. 6B is a perspective view of an end of a nozzle plate according to one embodiment, showing the conical thread of FIG. 6A.

[0022] [Figure 6C] 6B is a perspective view similar to FIG. 6B, illustrating how the conical screw of FIG. 6A is operated, according to one embodiment.

[0023] [Figure 6D] FIG. 6B is a top view of a printhead, nozzle plate, and base plate with the conical screw of FIG. 6A in accordance with one embodiment.

[0024] [Figure 7A] FIG. 13 is a perspective view showing an end of a nozzle plate on a base plate according to an embodiment, with a position fixing element provided thereon.

[0025] [Figure 7B] FIG. 7B is a perspective view similar to FIG. 7A, showing a state in which a position adjustment element and a position fixing element are provided, according to one embodiment.

[0026] [Figure 8A] FIG. 13 is a side view of a fastening element for fastening one end of a nozzle plate to a base plate, according to one embodiment. [Figure 8B] FIG. 13 is a side view of an alternative fastening element for fastening the other end of the nozzle plate to the base plate, according to one embodiment.

[0027] [Figure 8C] FIG. 13 is a cross-sectional view of a fastening element according to an alternative embodiment.

[0028] [Figure 8D] FIG. 2 illustrates a top view of a printhead, a nozzle plate, and a portion of a base plate in accordance with an embodiment.

[0029] [Figure 8E] FIG. 2 is a partial top perspective view of the bottom of a printing tile according to one embodiment.

[0030] [Figure 8F] FIG. 8F is a partial cross-sectional view of the biasing element of FIG. 8E, according to one embodiment.

[0031] [Figure 9A] FIG. 2 is a partial top perspective view of the bottom of a printing tile showing a base plate, nozzle plate, and printhead according to one embodiment.

[0032] [Figure 9B] FIG. 9B is a schematic cross-sectional view taken along line II-II of FIG. 9A according to one embodiment.

[0033] [Figure 9C] FIG. 9B is a schematic cross-sectional view taken along line III-III in FIG. 9A according to one embodiment.

[0034] [Figure 9D] 9D is a side view and a top view of the attachment element of FIG. 9C according to one embodiment.

[0035] [Figure 10A] FIG. 2 is a perspective view showing the top of a printing tile and a corresponding connector portion of a feeding mechanism that mates with the printing tile, according to one embodiment.

[0036] [Figure 10B] 1A-1C are schematic cross-sectional views illustrating one state during mating of the top of a printing tile with a corresponding connector portion of a feeding mechanism, according to one embodiment. [Figure 10C] 11 is a schematic cross-sectional view illustrating another state during mating of the top of a printing tile with a corresponding connector portion of a feeding mechanism, according to one embodiment. [Figure 10D] 11 is a schematic cross-sectional view illustrating another state during mating of the top of a printing tile with a corresponding connector portion of a feeding mechanism, according to one embodiment. [Figure 10E] 11 is a schematic cross-sectional view illustrating another state during mating of the top of a printing tile with a corresponding connector portion of a feeding mechanism, according to one embodiment.

[0037] [Figure 11A] FIG. 2 is a bottom view of a printhead assembly according to one embodiment.

[0038] [Figure 11B] FIG. 11B is an enlarged view of a region of FIG. 11A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] In the following disclosure, a number of embodiments or examples are shown for implementing various features of the present subject matter. Specific examples of components, values, operations, materials, arrangements, etc. described below are provided to facilitate understanding of the description of the present subject matter. Of course, these specific examples are merely illustrative and are not intended to be limiting. Other components, values, operations, materials, arrangements, etc. are also contemplated. For example, although reference numbers and / or characters may be repeated in the present disclosure in each example, such repetition is for simplicity and clarity and does not dictate a relationship between the various embodiments and / or configurations described herein. Furthermore, for convenience of explanation, spatially relative terms such as "below," "under," "lower," "above," and "upper" may be used herein to describe the relationship of one element or feature shown in each figure to another element or feature. These spatially relative terms are intended to encompass various orientations of the device during use or operation in addition to the orientation depicted. The device may be placed in other orientations (rotated 90 degrees or placed in other orientations), and the spatially relative descriptions used herein may be interpreted accordingly.

[0040] In an embodiment, an inkjet printer includes a printhead assembly having a number of removable and replaceable print tiles. Each print tile includes a number of removable and replaceable print heads. Each print head includes a number of nozzles that eject print material during a printing operation. To achieve high print quality, it is useful to align the nozzles of the multiple print heads. To this end, in at least one embodiment, each print head is attached to a nozzle plate, and the nozzle plate is attached to a base plate of the print tile using a number of mounting elements that allow the position of the nozzle plate to be adjusted in at least one direction. This allows the position of the print head attached to the nozzle plate, and the corresponding nozzles, to be adjusted in at least one direction. In this specification, unless otherwise specified, the position of the print head (and adjustment and / or alignment of the print head) refers to the position of the nozzle plate attached to the print head (and adjustment and / or alignment of the nozzle plate). The at least one direction in which the position of the print head can be adjusted may be any one or more of translational directions along the x-axis, y-axis, and z-axis, and / or any one or more of rotational directions about the x-axis, y-axis, and z-axis. In at least one embodiment, the mounting elements further allow for thermal expansion of the printhead and / or attached nozzle plate in at least one direction. In at least one embodiment, each print tile is removably mounted to a feed mechanism of the printhead assembly by a blind connection mechanism using at least one pair of alignment pins and alignment holes. One or more advantages are achieved in the embodiments described herein.

[0041] 1 is a top perspective view of an inkjet printer 100 according to one embodiment. The inkjet printer 100 has a heavy base 102 on which a substrate support 104 and a print support 106 are mounted. The substrate support 104 is a floating support that forms a gas cushion above its surface to support the substrate without contacting the surface. In this example, the base 102 sits on two floating supports 108 that levitate the base 102 on the gas cushion.

[0042] The substrate support 104 extends from a first end 110 of the inkjet printer 100 to a second end 112 opposite the first end 110. Gas for the floating support is provided to a number of openings 114 in a surface of the substrate support 104. The print support 106 includes a first stand 122 located on a first side 123 of the substrate support 104 and a second stand (not shown) located on a second side 125 of the substrate support 104 opposite the first side 123, with the substrate support 104 extending between the first stand 122 and the second stand. The substrate support 104 has a longitudinal dimension generally defining an axis referred to as the "y" axis that extends from the first end 110 to the second end 112. The first and second stands extend from the base 102 in a direction that defines an axis referred to as the "z" axis that is perpendicular to the y axis. A substrate handler 134 is positioned along the substrate support 104 to move the substrate along the substrate support 104 during processing.

[0043] The print support 106 includes a printhead assembly support 124 that rests on the first and second stands. The printhead assembly support 124 extends in a direction that defines an axis referred to as an "x" axis that is perpendicular to the y and z axes. A printhead assembly 126 is coupled to the printhead assembly support 124 via a printhead carrier (not shown). The printhead carrier moves the printhead assembly 126 along the printhead assembly support 124, for example, by using a gas cushion. This causes the printhead assembly 126 to move along the x-axis. An actuator that provides power to move the carrier along the x-axis direction is controlled by a controller (e.g., controller 150).

[0044] In one embodiment, the controller 150 comprises at least one hardware processor configured to control one or more operations of the inkjet printer 100 described herein. Such processors include, by way of example only, but not limited to, a microprocessor, a central processing unit (CPU), a multiprocessor, a distributed processing system, an application specific integrated circuit (ASIC), and the like. In at least one embodiment, the controller 150 further comprises a non-transitory computer readable storage device for storing data and / or software used and / or executed by the processor. The storage device includes electronic, magnetic, optical, electromagnetic, infrared, and / or semiconductor systems (or apparatus or devices) for non-transitory storage of instructions and / or data. For example, the storage device may include semiconductor or solid state memory, magnetic tape, removable computer diskettes, random access memory (RAM), read only memory (ROM), rigid magnetic disk, and / or optical disk. As an example of an optical disk, the storage device may include a compact disk ROM (CD-ROM), a rewritable compact disk R / W (CD-R / W), and / or a digital video disk (DVD). In at least one embodiment, the control unit 150 further comprises at least one interface circuit for communicating with external devices and / or a user. For example, the interface circuit includes one or more of a network interface, a keyboard, a keypad, a mouse, a trackball, a trackpad, cursor direction keys, a card reader, a communication port, a display, a signal light, a printer, and / or an audio device for communicating information to and from the processor. For example, the network interface includes one or more of a wireless network interface such as BLUETOOTH (registered trademark), WIFI, WIMAX, GPRS, WCDMA (registered trademark), or a wired network interface such as ETHERNET, USB, IEEE-1394, etc. In one embodiment, the control unit 150 comprises several independent control units, each configured to control one or more operations or functions of the inkjet printer 100.The inkjet printer 100 configuration described above is an example, and other inkjet printer configurations are within the scope of various embodiments.

[0045] In at least one embodiment, the substrate support 104 supports the substrate while the substrate moves along a y-axis direction to deposit print material onto the substrate during a printing operation. The printhead assembly 126 is coupled to the printhead assembly support 124 and moves along the printhead assembly support 124 in an x-axis direction to eject and deposit print material from the printhead assembly 126 onto the substrate below.

[0046] 2 is a bottom perspective view of a printhead assembly 126 according to one embodiment, in which the printhead assembly 126 is shown as viewed from below, i.e., looking up from the substrate support 104.

[0047] The printhead assembly 126 includes a housing 200 and a plurality of print tiles 202. The plurality of print tiles 202 are supported by the housing 200 and are arranged in a staggered arrangement in rows. Each print tile 202 includes a plurality of print heads 204, each print head 204 including a plurality of nozzles. Although FIG. 2 illustrates three print heads 204 for each print tile 202, this configuration is merely an example. Any number of print heads per print tile is possible, for example, two or four print heads per print tile. The nozzles are very small and are not explicitly shown in FIG. 2. In at least one embodiment, the nozzles of each print head 204 are arranged in an array having multiple rows and columns. During a printing operation, a printing material is ejected from the nozzles of one or more print heads 204 and advanced toward a substrate disposed on the substrate support 104. One or more of the plurality of print tiles 202 can be removed and / or rearranged to change the configuration of the print tiles and / or print heads based on printing requirements. For example, if a large number of print materials need to be deposited on a substrate, a printhead assembly with many nozzles or print tiles can be used to deposit the large number of materials in a more versatile manner. Alternatively, if less material is to be deposited, a printhead assembly with fewer nozzles or print tiles can be used to provide all the flexibility needed to deposit the material while still allowing for faster processing and faster printing of designs. The print tile and printhead configurations described above are exemplary. Other configurations are within the scope of various embodiments. For example, in at least one embodiment, the printhead assembly 126 may include a single print tile 202 rather than multiple print tiles, and / or each print tile 202 may include a single print head 204 rather than multiple print heads.

[0048] The housing 200 further includes a receiving portion 206 adjacent the printhead 204 and a receiving portion 208 above the printhead 204 (in the z-axis direction). The receiving portions 206, 208 at least partially house a fluid recirculation circuit that is supported by the housing 200 and recirculates printing material (e.g., fluid or liquid) to and from each of the printheads 204. In one configuration, the fluid recirculation circuit includes one or more reservoirs housed in the receiving portion 206 and a delivery system having one or more manifolds, conduits, and / or valves housed in the receiving portion 208. The delivery system recirculates printing material between the reservoirs and the printheads 204.

[0049] 3 is an elevated perspective view of a print tile 302 of a printhead assembly according to one embodiment. In an embodiment, the print tile 302 corresponds to any one of the print tiles 202 of the printhead assembly 126 described herein. The print tile 302 includes a fluidic component 342 and an electronic component 344, which are assembled together by a cage 329 to form the print tile 302.

[0050] The fluid member 342 has three printheads 304 mounted to corresponding nozzle plates A through C attached to a base plate 320. In one embodiment, the printheads 304 correspond to the printheads 204 described herein. Unless otherwise noted, each printhead 304 is similarly constructed to each other, and the corresponding nozzle plates A through C are similarly constructed to each other. The number of printheads 304 and corresponding nozzle plates may be other than three.

[0051] The printheads 304 are attached to the base plate 320 via corresponding nozzle plates A to C. The base plate 320 allows the printing tiles 302 to be securely mounted to the printhead assembly 126. The base plate 320 also has openings through which the nozzles (not shown) of the printheads 304 are exposed on a nozzle face (not shown) of the base plate 320. The printheads 304 are aligned on the base plate 320. Thus, the nozzles of all the printheads 304 are substantially flush with the nozzle face of the base plate 320, and the opposite edges of the printheads 304 are also aligned. The printheads 304 are spaced apart from one another along the base plate 320, with adjacent printheads 304 equally spaced apart (e.g., along the y-axis). Although not shown in FIG. 3, each printhead 304 has a number of print nozzles. The number of print nozzles are distributed in one or more rows along the longitudinal axis of the printhead 304 (e.g., along the x-axis). Various configurations according to several embodiments for mounting printheads 304 to a base plate 320 via corresponding nozzle plates A-C are described with reference to Figures 5A-9D.

[0052] The print heads 304 are fluidly coupled to a fluid conduit system for delivering and returning printing material to and from the print heads 304. The fluid conduit system includes a supply conduit 310 and a return conduit 312. The supply conduit 310 is fluidly coupled to a first side 336 of each print head 304. The return conduit 312 is fluidly coupled to a second side 338 of each print head 304, opposite the first side 336. The supply conduit 310 and the return conduit 312 are fluidly coupled to fluid connectors 380, 382, ​​respectively, on an end plate 362 of the printing tile 302. The end plate 362 is located on the opposite side of the height (e.g., z-axis) of the printing tile 302 from the base plate 320. The supply conduit 310 extends from the fluid connector 380 to a supply manifold 368 on the first side 336 of the print head 304. The flow provided from the supply conduit 310 is split into three flows inside the supply manifold 368. The split flows are provided from the supply manifold 368 to the first side 336 of each print head 304 via three conduits 373 (one of which is not shown in FIG. 3 ). This delivers the printing material to each print head 304. The supply manifold 368 is configured to deliver the printing material to each print head 304 with substantially no pressure loss variations. This allows the nozzles of the print heads 304 to be controlled to precisely eject the printing material. Similarly, a return manifold 376 is provided having an outlet conduit (not shown in FIG. 3 ). The return manifold 376 fluidly couples the second side 338 of each print head 304 to the return conduit 312. The printing material circulates to and from the print heads 304 through the supply conduit 310 and the return conduit 312. This allows the homogeneity of the printing material to be maintained while printing is in progress or paused. This allows the printing material to circulate to and from the printheads 304 of the printhead assembly 126 while the printing material is not being ejected from the nozzles of the printheads 304, thereby maintaining the printing material mixed.

[0053] The cage 329 includes four strength members 350 (one of which is not shown in FIG. 3). The strength members 350 are arranged in a rectangle and extend parallel to each other along the height direction (e.g., z-axis direction) of the printing tile 302. The cage 329 also includes two web members (a first web member 352A and a second web member 352B) connected to all the strength members 350, which provides structural rigidity. Each of the web members 352A and 352B is a U-shaped member that extends along three sides of the rectangle defined by the strength members 350 and linearly connects adjacent strength members 350. The base plate 320 engages with the lower end of the strength member 350, and the end plate 362 engages with the upper end of the strength member 350. In this way, the cage 329 is completed.

[0054] In an alternative embodiment, each strength member 350 includes a lower strut and an upper strut, and the second web member 352B is replaced by an upper mounting plate and a lower mounting plate. The lower strut of each strength member 350 extends between and connects the base plate 320 and the lower mounting plate. The upper strut of each strength member 350 extends between and connects the upper mounting plate and the end plate 362. The upper mounting plate and the lower mounting plate are fastened together by a plurality of spring-loaded shoulder screws. Each shoulder screw has a compression spring disposed between the upper mounting plate and the lower mounting plate. This allows the upper portion of the cage 329, including the end plate 362, the upper strut, and the upper mounting plate, to be resiliently raised by the spring while being attached to the lower portion of the cage 329, including the lower mounting plate, the lower strut, and the base plate 320. In other embodiments, the springs may be tension springs. Other resilient fasteners may be used.

[0055] The electronics member 344 includes a drive box 330 that houses the printhead drive circuitry. The drive box 330 is attached to an electronics support plate 354, which is in turn attached to a second web member 352B. The electronics support plate 354 provides structural support and positions the electronic components of the print tile 302, thereby enabling electrical connections to be made. The drive box 330 is attached to the electronics support plate 354 and is positioned between the electronics support plate 354 and the first web member 352A. An electronic interface member 360 is attached to the electronics support plate 354 and is located between the electronics support plate 354 and an end plate 362.

[0056] The end plate 362 structurally supports the electrical and fluid connections between the printing tile 302 and the supply assembly. The supply assembly provides fluid, control, and electrical supplies to the printing tile 302 (e.g., the supply mechanism 428 described with reference to FIG. 4A). The end plate 362 has an electronics opening 390 for electrical connection between the electronic interface member 360 and the printer's control circuitry (e.g., the controller 150). In addition to the fluid connectors 380, 382 described herein, the end plate 362 further includes alignment holes 384, 386 and a threaded hole 388 for blind connection with the supply mechanism (described below with reference to FIGS. 10A-10E). The end plate 362 includes a protective wall 363. The protective wall 363 surrounds the fluid connectors 380, 382, ​​the alignment holes 384, 386, and the threaded hole 388.

[0057] FIG. 4A is a partially exploded top perspective view of printhead assembly 126 according to one embodiment.

[0058] The printhead assembly 126 includes a tile support structure 420 that holds the print tiles 302. The tile support structure 420 includes a support plate 422. The support plate 422 allows a supply manifold and a return manifold of the print material to be coupled to the print tiles 302. The support plate 422 includes a plurality of partitions 424. The plurality of partitions 424 guide the positioning of the print material manifold of each print tile and position and engage the electrical connections of each print tile 302. A groove 434 is defined between each partition 424. The cage 329 positions the print tiles 302 in the corresponding groove 434. This allows the print head of the print tile 302 to be accurately positioned within the printhead assembly 126. Each groove 434 defines a row of the print tiles 302.

[0059] The print head assembly 126 further includes a supply plate 426 oriented substantially parallel to the support plate 422. Each printing tile 302 extends substantially from the support plate 422 to the supply plate 426. A supply mechanism 428 is coupled to the supply plate 426. The supply mechanism 428 is disposed proximate each printing tile 302 and provides liquid, gas, control, and electrical supplies to the printing tile 302. A cage 329 for each printing tile 302 extends from the support plate 422 to the supply plate 426 and structurally houses and provides strength to the printing tile 302. This allows the printing tiles 302 to be handled as a unit. The supply mechanism 428 includes valves 431 that control the flow of printing material to and from each printing tile 302. The valves 431 for each printing tile 302 include at least a supply valve that controls the flow of printing material to the printing tile 302 and a return valve that controls the flow of printing material from the printing tile 302.

[0060] For each print tile 302, an enclosure 480 is disposed between the support plate 422 and the supply plate 426. The enclosure 480 guides the mounting of the print tile 302 and the connection of the print tile 302 to the supply mechanism 428 (the connection between the fluid connectors 380, 382 and the electronic interface member 460). The print tile 302 is inserted into the enclosure 480 through a print tile opening (not shown) in the support plate 422 and connected to the supply mechanism 428. In the region 411 shown diagrammatically in FIG. 4A, the supply plate 426 has one or more alignment structures (shown diagrammatically as 484 in FIG. 4B). The alignment structures protrude from the supply plate 426 and engage with corresponding alignment holes in the top of the cage 329 (e.g., the end plate 362). This ensures that the various fluid and electrical connections of the print tile 302 are connected when the print tile 302 is installed in the printhead assembly 126. The base plate 320 of the printing tile 302 is attached to the support plate 422, and the printing tile 302 is fixed within the print head assembly 126. The detailed configuration of the area 411 where the printing tile 302 and the supply mechanism 428 are blind-connected will be described with reference to Figures 10A to 10E.

[0061] FIG. 4B is a bottom perspective view, partially exploded, of the printhead assembly of FIG. 4A according to one embodiment.

[0062] FIG. 4B is a bottom view of the same structure as in FIG. 4A. The print tiles 302 are inserted into the enclosure 480 through tile openings 482 in the support plate 422 and connected to the feed mechanism 428. When fully inserted, the top surface of the base plate 320 (or the top base plate mounting pad) contacts the bottom surface 483 of the support plate 422. The bottom surface 483 of the support plate 422 defines a common mounting surface for the base plates of all the print tiles 302. This facilitates alignment of the nozzles at least in the z-axis direction between all the print heads in the print head assembly 126 (described below with reference to FIGS. 5C-5E and 9A-9D). Other structures for defining a common mounting surface for multiple print tiles are within the scope of various embodiments.

[0063] FIG. 5A is a partial top perspective view of the bottom of a printing tile 500 according to one embodiment.

[0064] The print tiles 500 include a base plate 502 and nozzle plates 504 attached to corresponding print heads 506 (only one print head 506 corresponding to nozzle plate B is shown in FIG. 5A). In an embodiment, the print tiles 500 correspond to the print tiles 202, 302 and include other components as described with reference to FIG. 3. Other print tile configurations are within the scope of various embodiments. In an embodiment, the base plate 502 corresponds to the base plate 320 and / or the print heads 506 correspond to the print heads 204, 304. The individual nozzle plates 504 are shown as nozzle plate A, nozzle plate B, and nozzle plate C. Unless otherwise noted, each nozzle plate 504 is similarly configured to the other. The number of nozzle plates 504 and the corresponding print heads 506 may be other than three. In FIG. 5A, the nozzle plate A is shown in wire frame form, and the print head 506 corresponding to the nozzle plate A is omitted to show the features of the other components.

[0065] The base plate 502 has a top surface 501, a bottom surface 503 opposite the top surface 501 in a thickness direction (e.g., z-axis direction) of the base plate 502, and a slot 505 passing through the base plate 502 from the top surface 501 to the bottom surface 503. The top surface 501 is in the xy plane. The slot 505 extends along the x-axis direction. The top surface 501 of the base plate 502 is further provided with a mounting feature 575 (e.g., a hole or a post) for mounting to a strength member 350 (see FIG. 3) of the cage 329.

[0066] Each nozzle plate 504 engages with the top surface 501 of the base plate 502 and is attached to a corresponding print head 506. The print head 506 has a lower portion 507 (see FIG. 5C) inserted into the slot 505. The print head 506 also includes a number of nozzles 577 (see FIG. 5C) that eject print material, for example, downward along the z-axis direction during a printing operation. The nozzle plates 504 are arranged side by side in the y-axis direction. The nozzle plates 504 extend along the x-axis direction. Each nozzle plate 504 also has a first end 508 and a second end 509 that are located opposite each other. The first end 508 and the second end 509 of the nozzle plate 504 are arranged on the top surface 501 of the base plate 502 and are configured to mount the nozzle plate 504 to the base plate 502.

[0067] The printing tile 500 further includes a number of mounting elements for mounting the nozzle plates 504 to the base plate 502 while allowing adjustment of the position of each nozzle plate 504 relative to the base plate 502. At least one direction in which the nozzle plate 504 can be adjusted may be any one or more of translational directions along the x-axis, y-axis, and z-axis, and / or any one or more rotational directions about the x-axis, y-axis, and z-axis. The rotational directions about the x-axis, y-axis, and z-axis are referred to herein as θ-x, θ-y, and θ-z, respectively.

[0068] The mounting elements may include any one or more of the mounting elements described herein depending on the direction in which the print head needs to be adjusted. In one example, for z-axis adjustment, the mounting elements include one or more spacers as described with reference to Figures 5C-5E and / or one or more adjustable elevators as described with reference to Figures 9A-9D. In another example, for θ-z adjustment, the mounting elements include one or more position adjustment elements as described with reference to Figures 6A-6D. In yet another example, for x-axis and / or y-axis adjustment (also referred to as xy adjustment), the mounting elements include one or more position adjustment elements as described with reference to Figures 7A and 7B. In cases where the xy position of the print head is fixed and no xy adjustment is desired or required, one or more of the position adjustment elements are replaced with one or more corresponding fixed position elements as described further with reference to Figures 7A and 7B. In yet another example, the mounting elements allow the print head to thermally expand in a given direction as described with reference to Figures 8A-8F. The mounting elements for each printhead may be individually adjusted and / or configured differently from the mounting elements for other printheads on the same base plate. In other words, each printhead may be mounted and / or adjusted separately from the other printheads on the same base plate to achieve the desired nozzle alignment between the printheads. In some embodiments, a kit is provided for each printhead, including multiple or all of the mounting elements described herein. Depending on the actual direction in which the printhead needs to be aligned, the end user may select one or more mounting elements of the required type from the kit to mount and / or adjust the printhead on the base plate.

[0069] In the example configuration of Figure 5A, the multiple mounting elements for each printhead (e.g., for nozzle plate A) include a first fastening element 510 and a second fastening element 520 that fasten a first end 508 and a second end 509 of nozzle plate A to the base plate 502, respectively. Each of the first fastening element 510 and the second fastening element 520 includes a bolt or screw that is fastened to a nut to clamp the base plate 502 and the nozzle plate A. Other fastener configurations are within the scope of various embodiments. Example configurations of the first fastening element 510 and / or the second fastening element 520 are described with reference to Figures 5C, 8A-8C, and 9A-9D.

[0070] The mounting elements for each print head (e.g., for nozzle plate A) further include a position adjustment element 530 and an additional mounting element 540 for fixing and / or adjusting the position of the nozzle plate A. Specifically, the position adjustment element 530 is disposed at a first end 508 of the nozzle plate A and fixes and adjusts the position of the first end 508 in the xy plane. The additional mounting element 540 is disposed at a second end 509 of the nozzle plate A and fixes and / or adjusts the position of the second end 509 in the xy plane. If the position of the second end 509 in the xy plane does not need to be adjusted and only needs to be fixed, the additional mounting element 540 may be a position fixing element. Examples of the position fixing element include a cylindrical support fixed to the upper surface 501 of the base plate 502, or a screw screwed into the upper surface 501. If it is required to fix and adjust the position of the second end 509 in the xy plane, the additional mounting element 540 may be a position adjustment element similar to the position adjustment element 530.

[0071] FIG. 5B is a top view of nozzle plate A of FIG. 5A, a corresponding printhead 506, and the portion of base plate 502 disposed thereunder, according to one embodiment.

[0072] As shown in Figure 5B, the printhead 506 includes a pair of inlets and outlets (both shown as 573). The inlets are coupled to conduits 373 (not shown in Figure 5B) that supply printing material to the printhead 506. The outlets are coupled to conduits 373 (not shown in Figure 5B) that return printing material from the printhead 506. Also shown in Figure 5B is an electrical connector 590. The electrical connector 590 is electrically coupled to the drive box 330 (not shown in Figure 5B) for receiving electrical and control signals for controlling the nozzles of the printhead 506 to eject printing material during a printing operation.

[0073] The first end 508 of the nozzle plate A includes a notch 531 recessed toward the first fastening element 510. The position adjustment element 530 is at least partially disposed within the notch 531 and engages a side surface 532 of the first end 508 at the notch 531. The side surface 532 of the first end 508 is located between the position adjustment element 530 and the first fastening element 510. In some embodiments, the notch 531 need not be provided.

[0074] The second end 509 of the nozzle plate A includes a notch 541. A side wall 542 and a side wall 543 of the notch 541 meet at a smaller distance from each other in a longitudinal direction (i.e., the x-axis direction) of the print head 506 or the nozzle plate A from the second end 509 to the first end 508. The additional mounting element 540 is at least partially disposed within the notch 541 and engages with the side walls 542, 543 of the notch 541. The side wall 542 of the notch 541 is located between the additional mounting element 540 and the second fastening element 520. The V-shaped notch 541 as shown in FIG. 5B is an example. Other shapes of the notch 541 are within the scope of various embodiments.

[0075] In the configuration example of FIG. 5B, the second end 509 further includes another notch 561. A positioning pin 562 formed on the upper surface 501 of the base plate 502 is disposed in the other notch 561. The other notch 561 and the positioning pin 562 are used when initially aligning and / or positioning the nozzle plate A on the upper surface 501. That is, they are used before fastening the nozzle plate A to the base plate 502 and / or before adjusting the position of the nozzle plate A relative to the upper surface 501. The first end 508 may also be provided with another notch and a corresponding pair of positioning pins similar to those described above. In some embodiments, the second end 509 may not be provided with the other notch 561 and the positioning pin 562. Additionally or alternatively, the first end 508 may not be provided with another notch and a pair of positioning pins similar to those described above.

[0076] The additional mounting element 540 engaging with the side walls 542, 543 of the notch 541 at least fixes the position of the second end 509 in the longitudinal direction (i.e., the x-axis direction) and in the transverse direction intersecting the longitudinal direction (i.e., the y-axis direction) of the nozzle plate A. If the additional mounting element 540 is a position adjustment element as described herein, the additional mounting element 540 further allows for adjustment of the position of the second end 509 (and the nozzle plate A as a whole) in the x-axis direction.

[0077] The additional mounting element 540 may further allow some rotation of the first end 508 in the θ-z direction, i.e., rotation of the first end 508 in the θ-z direction about an axis along the z-axis direction that passes through the additional mounting element 540 at the second end 509. Such θ-z rotation may adversely affect the parallelism of the printheads on the same base plate, i.e., one printhead may become non-parallel to the other printheads, which may adversely affect nozzle alignment between the multiple printheads. The position adjustment element 530 that engages the first end 508 allows for θ-z rotational position adjustment of the first end 508. The θ-z adjustment provided by the position adjustment element 530 ensures the desired parallelism between the printheads and achieves the desired nozzle alignment between the multiple printheads. Details of the position adjustment element 530 and / or the additional mounting element 540 are further described with reference to Figures 6A-7B.

[0078] FIG. 5C is a schematic cross-sectional view taken along line II in FIG. 5A, according to one embodiment.

[0079] 5C shows an example of the internal structure of the first fastening element 510 and the position adjustment element 530. The first fastening element 510 includes a bolt 511, a nut 518, and a washer 519. The bolt 511 extends in the z-axis direction and has a head 512 at its lower end and a thread 513 at its upper end. The head 512 is inserted into a hole 514 that extends from the lower surface 503 to the upper surface 501 of the base plate 502. The hole 514 is more open at the lower surface 503 than at the upper surface 501, thereby forming a shoulder 515 that engages with the head 512 of the bolt 511. The bolt 511 further extends through a hole 516 in the first end 508, and the thread 513 is exposed above the upper surface 517 of the first end 508. A nut 518 is fastened onto threads 513, and a washer 519 is interposed between the nut 518 and an upper surface 517 of the first end 508. The first end 508 and base plate 502 are clamped in the z-axis direction between the nut 518 and the head 512 of the bolt 511. In one embodiment, the washer 519 is a wave washer, as described below with reference to FIG. 8A. In at least one embodiment, the washer 519 is a regular washer or other type of washer. Alternatively, no washer may be provided.

[0080] The second fastening element 520 is configured similarly to the first fastening element 510, and includes a bolt 521 and a nut 528. The bolt 521 extends in the z-axis direction through a hole 524 in the base plate 502 and a hole 526 in the second end 509 of the nozzle plate A. The bolt 521 also has a head 522 at its lower end and a thread (not numbered) at its upper end. A nut 528 is fastened to the thread of the bolt 521. A washer may or may not be interposed between the nut 528 and the upper surface (not numbered) of the second end 509. The second end 509 and the base plate 502 are fastened in the z-axis direction between the nut 528 and the head 522 of the bolt 521. The bolt-nut configurations of the first fastening element 510 and the second fastening element 520 described above are merely examples. Other fastening configurations are also within the scope of various embodiments.

[0081] As shown in FIG. 5C, the print head 506 includes an upper portion that is above the upper surface 501 of the base plate 502 and a lower portion 507 that is below the upper surface 501 and is at least partially inserted into the slot 505. The lower portion 507 includes a nozzle 577 having an opening or orifice at a lower surface of the lower portion 507. The lower surface of the lower portion 507 defines a nozzle face 578. In one embodiment, it is desirable to mount the print heads to the same base plate such that the nozzle faces 578 of all the print heads are coplanar. In at least one embodiment, the nozzle faces 578 are considered coplanar when they are parallel and are offset from each other along the z-axis by only a few microns (e.g., less than 100 microns). Other criteria for defining a nozzle face as coplanar are within the scope of various embodiments.

[0082] In one embodiment, the nozzle face 578 of the printhead is parallel to the mounting surface of the base plate when each printhead is mounted using corresponding mounting elements. This ensures that the nozzle faces of printheads on the same base plate are coplanar with each other. In FIG. 5C, for simplicity, the mounting surface is shown as corresponding to the top surface 501 of the base plate 502. Other structures for defining the mounting surface are within the scope of various embodiments (e.g., as described below with reference to FIG. 5D). A measurement device (e.g., a laser measurement device) is used to measure a first offset of the nozzle face 578 from the mounting surface at the first end 508 and a second offset of the nozzle face 578 from the mounting surface at the second end 509. If the first and second offsets are the same or are different within a few microns, the nozzle face 578 is considered parallel to the top surface 501. Otherwise, the nozzle face 578 is considered non-parallel to the top surface 501.

[0083] In order to make the nozzle surface 578 of the print head 506 parallel to the mounting surface, one or more spacers having a predetermined thickness are inserted between the upper surface 501 of the base plate 502 and at least one of the first end 508 or the second end 509 of the nozzle plate A. This adjustment corresponds to θ-y adjustment because the print head to be adjusted rotates around an axis substantially along the y-axis direction. Specifically, on the first end 508 side, one or more spacers (schematically shown as number 552) are inserted around the bolt 511 between the first end 508 and the upper surface 501. On the second end 509 side, one or more spacers (schematically shown as number 554) are inserted around the bolt 521 between the second end 509 and the upper surface 501. In one example, when the nozzle surface 578 is farther from the mounting surface on the first end 508 side than on the second end 509 side, the total thickness of the spacers 552 is selected to be greater than the total thickness of the spacers 554. Additionally, the number and / or thickness of the spacers 552, 554 are selected so that the nozzle face 578 of the printhead 506 is spaced a predetermined distance from the mounting surface that is substantially equal to the spacing of the nozzle faces 578 of other printheads on the same base plate 502 from the mounting surface, such that the nozzle faces 578 of all of the printheads are coplanar and spaced the same predetermined distance from the mounting surface.

[0084] In one example, spacers 552, 554 are selected from spacers having different predetermined thicknesses, such as 25.4 microns (0.001 inch), 38 microns (0.0015 inch), 50.8 microns (0.002 inch), etc. By selecting one or more spacers having one or more of the above thicknesses, it is possible to achieve coplanarity of 12.5 microns (0.0005 inch) or less. Spacers having other thicknesses are also within the scope of various embodiments. In one embodiment, the spacers are made of metal or other suitable material.

[0085] As described with reference to FIG. 4B, all the printing tiles have the same and common mounting surface when inserted and mounted in the print head assembly. The print heads are mounted on the individual printing tiles so that the print heads are coplanar and are located at equal predetermined distances from the mounting surfaces of the printing tiles. This allows the print heads of all the printing tiles to be coplanar when mounted in the print head assembly so that they have a common mounting surface. This provides the advantages of ease of control, high printing quality, and the like.

[0086] FIG. 5D illustrates a top view of the nozzle plate 504, print head 506, and base plate 502 of FIG. 5A with spacers 552, 554 interposed, according to one embodiment.

[0087] In the configuration example of Figure 5D, spacers 552, 554 are inserted at all ends of all nozzle plates A, B, and C, but it is possible that a spacer is not inserted at at least one end of at least one nozzle plate.

[0088] As shown in FIG. 5D, the top surface 501 of the base plate 502 is further provided with a base plate mounting pad 580. The base plate mounting pad 580 contacts a support structure of a printhead assembly, for example as described with reference to FIG. 4B. In this configuration, the base plate mounting pad 580 defines the mounting surface of the base plate 502. In some embodiments, the base plate mounting pad 580 may not be provided. In that case, the mounting surface of the base plate 502 is the top surface 501. Other structures for defining the mounting surface of the base plate 502 are within the scope of various embodiments.

[0089] FIG. 5D further illustrates the biasing element 560. Each biasing element 560 is provided on the first end 508 of the corresponding nozzle plate 504. For example, the biasing element 560 corresponding to the nozzle plate A engages with the side 533 of the first end 508 of the nozzle plate A. The side 533 is opposite to the side 532 with which the position adjustment element 530 engages in the y-axis direction. The first fastening element 510 is disposed between the position adjustment element 530 and the biasing element 560. The biasing element 560 resiliently biases the first end 508 of the nozzle plate A toward the position adjustment element 530. In one embodiment, the biasing element 560 includes a spring that presses against the side 533. Other structures for pressing against the side 533 are also within the scope of various embodiments. The biasing element 560 allows the first end 508 of the nozzle plate A to thermally expand in the y-axis direction or the θ-z direction due to temperature deviations. When the temperature returns to ambient or nominal temperature, the first end 508 is returned to its original position by the biasing element 560. This ensures alignment of the nozzles between the printheads and / or print tiles. The biasing elements 560 for the other nozzle plates B, C function in a similar manner.

[0090] Figure 5E is a top perspective view of a spacer 564 according to one embodiment. The spacer 564 of Figure 5E is an example of one or more of the spacers 552, 554 described with reference to Figures 5C and 5D.

[0091] The spacer 564 includes a body 565 having a curved notch 566 at one end and an operating portion 567 at the opposite end. The notch 566 is positioned to surround the corresponding bolt 511 or bolt 521 when the spacer 564 is inserted between the base plate 502 and the first end 508 or second end 509 of the nozzle plate. The operating portion 567 is configured to facilitate operation (e.g., installation or removal) of the spacer 564 between the nozzle plate and the corresponding base plate. The spacer configurations described above are examples. Other spacer configurations are within the scope of various embodiments.

[0092] FIG 6A is a side view of a conical screw 630 according to one embodiment. FIG 6B is a perspective view of a first end 508 of a nozzle plate 504 with the conical screw 630 of FIG 6A in place. FIG 6C is a perspective view similar to FIG 6B, illustrating how the conical screw 630 of FIG 6A is manipulated. The conical screw 630 is an example of a position adjustment element 530. In some embodiments, the conical screw 630 can also be used as an additional attachment element 540.

[0093] 6A, the conical thread 630 includes a head 631, a conical portion or surface 632, and threads 633, arranged in this order. The head 631 is configured to engage a tool to rotate the conical thread 630. The conical surface 632 tapers gradually from the head 631 to the threads 633.

[0094] 6B, conical screw 630 is attached to base plate 502 by engaging threads 633 with threaded holes 634 in top surface 501. Conical surface 632 engages side surface 532 of first end 508 of nozzle plate 504.

[0095] As shown in FIG. 6C, when the conical screw 630 is turned (e.g., by a tool engaging the head 631) into the threaded hole 634, the conical surface 632 pushes the first end 508 toward the right in the y-axis direction (see arrow 635 in the figure). When the conical screw 630 is turned out of the threaded hole 634, the conical surface 632 allows the first end 508 to move back toward the left in the y-axis direction (see arrow 636 in the figure). The first end 508 of the nozzle plate 504 may move back due to the material properties of the nozzle plate 504 and / or the biasing element 560 (not shown in FIG. 6C). In one configuration, turning the conical screw 630 one-quarter (1 / 4) turn moves the first end 508 of the nozzle plate 504 approximately 10 microns. Other configurations are within the scope of various embodiments.

[0096] FIG. 6D illustrates a top view of the nozzle plate 504, printhead 506, and base plate 502 with conical threads 630 according to one embodiment.

[0097] As shown in FIG. 6D, the conical screw 630 engages with the first end 508 of the nozzle plate A and performs θ-z adjustment of the nozzle plate A in a rotation direction around the second end 509. This adjustment method is similar to the method described with reference to the position adjustment element 530 in FIG. 5B and FIG. 5D. Specifically, when the conical screw 630 is turned so as to screw into the top surface 501 of the base plate 502, the nozzle plate A is pressed by the conical screw 630 and rotates around the corresponding additional mounting element 540 (see arrow 637A in the figure). When the conical screw 630 is turned in a direction to loosen from the top surface 501, the first end 508 is allowed to rotate in the opposite direction to the arrow 637A. For the other nozzle plates B and C, the conical screws 630 are similarly operated to perform θ-z adjustment (see arrows 637B and 637C in the figure, respectively). The θ-z adjustment of each print head is performed separately from the other print heads. This allows the nozzle plates A, B, C and the corresponding print heads 506 to be adjusted to be parallel to each other, i.e., the parallelism of the print heads 506 is ensured. Thus, the rows and / or columns of nozzles of the print heads can be adjusted to be parallel to each other among multiple print tiles in the print head assembly, which can provide one or more advantages described herein, such as ease of control and high print quality. In one embodiment, the parallelism of the print heads is verified by imaging the print heads with a camera and processing the images with a processor, which determines the amount and direction of theta-z adjustment to be made to each print head.

[0098] FIG. 6D further illustrates additional mounting elements 660 for each of the nozzle plates A, B, and C. Specifically, the additional mounting element 660 for nozzle plate A is located in a similar position to the biasing element 560 described with reference to FIG. 5D. In one embodiment, the additional mounting element 660 is an element similar to the biasing element 560 and biases the nozzle plate A towards the corresponding conical thread 630. In another embodiment, the additional mounting element 660 defines the limits of the range over which the θ-z adjustment of the nozzle plate A can be made. In such an embodiment, the additional mounting element 660 is configured similarly to the additional mounting element 540 described herein. Additionally or alternatively, the additional mounting element 660 also defines how tightly the nozzle plates are fastened and / or how much room they have for thermal expansion.

[0099] Figure 7A is a perspective view of second end 509 of nozzle plates A, B, C on base plate 502 with position fixing elements 740A to 740C according to one embodiment, and Figure 7B is a perspective view similar to Figure 7A with position adjustment elements 730A, 730C and position fixing element 740B according to one embodiment.

[0100] In Fig. 7A, each of the position fixing elements 740A to 740C is disposed on and engages with a side wall of a notch of a corresponding nozzle plate, similar to the additional mounting element 540 described with reference to Figs. 5B and 5D. The position fixing elements 740A to 740C are disposed to fix the position of the corresponding printhead in the x-axis direction and are configured not to allow position adjustment in the x-axis direction. The position fixing elements 740A to 740C may be cylindrical posts formed integrally with or permanently attached to the top surface 501 of the base plate 502.

[0101] 7A , each of the position fixing elements 740A to 740C has a cylindrical upper portion and a lower portion having a screw thread (not shown) and is removably screwed into a corresponding screw hole 734A to 734C formed in the upper surface 501 of the base plate 502. This configuration allows one or more of the position fixing elements 740A to 740C to be removed and replaced with one or more corresponding position adjustment elements (e.g., conical screws) when position adjustment is required.

[0102] In the configuration example shown in FIG. 7B, the position fixing elements 740A, 740C in FIG. 7A are removed (unscrewed) from the corresponding screw holes 734A, 734C, and instead, the corresponding conical screws 730A, 730C are screwed into the corresponding screw holes 734A, 734C. The conical screws 730A, 730C have the same configuration and function as the conical screw 630. For example, the conical screw 734A has a conical surface 732. The conical surface 732 engages with the side walls 542, 543 of the notch provided in the second end 509 of the nozzle plate A. When the conical screw 734A is turned so as to be screwed into the base plate 502, the conical surface 732 is pressed against the side walls 542, 543, moving the nozzle plate A along the x-axis direction toward the first end 508. The further the conical screw 734A is screwed into the base plate 502, the further the nozzle plate A moves along the x-axis direction away from the conical screw 734A. Thus, the conical screw 734A can be used to adjust or fix the x-axis position of the nozzle plate A and the corresponding print head 506. The conical screw 734C functions in a similar manner. The above configuration in FIG. 7B is an example. Any one or more of the position fixing elements 740A to 740C can be replaced with a corresponding position adjustment element (e.g., a conical screw).

[0103] In one example of an alignment process, the positional fixing elements 740A-740C are initially (e.g., initially) positioned on the base plate 502. In this initial positioning, the x-axis positional accuracy is determined by the machining tolerances and the print head tolerances. In some cases, the machining tolerances are within 100 microns, and the print head tolerances are added to the machining tolerances. If the positional fixing elements 740A-740C provide an acceptable x-axis positional accuracy, the conical screws are not required. If it is determined that the x-axis positional accuracy needs to be improved, one or more of the positional fixing elements 740A-740C are replaced with a corresponding conical screw to adjust the x-axis. As described in the above example, a quarter turn of the conical screw allows for an adjustment of about 10 microns, which is often smaller than the machining tolerances and the print head tolerances. Thus, the x-axis positional accuracy of each print head can be improved, improving nozzle alignment between multiple print heads and / or multiple print tiles across the print head assembly.

[0104] 8A and 8B are side views of a first fastening element 510 and a second fastening element 520, respectively, for fastening a first end 508 and a second end 509 located on opposite sides of a nozzle plate 504 to a base plate 502, in accordance with one embodiment.

[0105] The first fastening element 510 in FIG. 8A is similar to that described with reference to FIG. 5C, but has an additional feature that the washer 519 in FIG. 5C is configured as a wave washer 819 in FIG. 8A. A washer 809 is disposed between the wave washer 819 and the nozzle plate 504. In one embodiment, the washer 809 is made of PEEK (polyether ether ketone) so as to allow the nozzle plate 504 to slide due to thermal expansion while being fixed. As described with reference to FIG. 8D, the torque of the nut 518 is controlled so as to allow the nozzle plate 504 to slide in the x-axis direction due to thermal expansion while fixing the nozzle plate 504 with the wave washer 819. The second fastening element 520 in FIG. 8B is similar to that described with reference to FIG. 5C.

[0106] FIG. 8C is a cross-sectional view of a fastening element 510 according to an alternative embodiment. Compared to FIG. 8A, the fastening element 510 of the alternative embodiment of FIG. 8C further includes a spacer 811 between the nut 518 (in this embodiment, a barrel screw) and the wave washer 819. The spacer 811 has an upper portion 812 and a lower portion 813. Compared to the upper portion 812, the thickness of the lower portion 813 is radially thinner, thereby forming a recessed area 814. The lower portion of the wave washer 819 is inserted into the recessed area 814. The upper portion 812 has a slot 815 into which the upper end of the wave washer 819 is inserted. This allows the bolt 511 to be held in the center of the wave washer 819. When the barrel screw 518 is screwed downward to tighten the wave washer 819, the wave washer 819 is prevented from moving radially to the side. The clamping force of the wave washer 819 is selected to fasten the first end 508 of the nozzle plate 504 to the base plate 502 in alignment with the other nozzle plates / printheads, while still allowing for thermal expansion of the first end 508 as described herein. In some embodiments, the lower portion 813 of the spacer 811 may not be provided.

[0107] FIG. 8D illustrates a top view of the nozzle plate 504, print head 506, and a portion of the base plate 502 according to one embodiment.

[0108] As described with reference to one or more of Figures 8A to 8C, the first end 508 and the second end 509 of the nozzle plate 504 are fastened to the base plate 502 by the first fastening element 510 and the second fastening element 520, respectively. As described with reference to Figure 5B, the position of the second end 509 in the x-axis direction is fixed by the additional mounting element 540 engaging the side wall of the notch 541. In the x-axis direction (i.e., the longitudinal direction of the nozzle plate 504), the nozzle plate 504 has a side 808 opposite the notch 541. The x-axis side 808 is not engaged or contacted by a mounting element or other feature. Thus, the nozzle plate 504 is free to thermally expand along the x-axis direction (i.e., the longitudinal direction of the nozzle plate 504) away from the notch 541, as indicated by the arrow 839. Such thermal expansion of the nozzle plate 504 is further facilitated by the provision of a wave washer 819, as described with reference to Figures 8A and 8C.

[0109] As described with reference to FIG. 5B, the first end 508 engages the alignment element 530 at the side 532 in the y-axis direction or θ-z direction. The alignment element 530 thus prevents the first end 508 from thermally expanding at the side 532. Meanwhile, the first end 508 is allowed to thermally expand away from the alignment element 530 at the opposite side 533, as indicated by arrow 849. In one embodiment, a biasing element 560 is provided to engage the side 533, as described with reference to FIG. 5D. Again, the biasing element 560 allows the first end 508 to thermally expand away from the alignment element 530 due to temperature deviations. When the temperature returns to the ambient or nominal temperature, the first end 508 returns to its initial position under the action of the biasing element 560. This ensures that the nozzles are aligned between the printheads and / or print tiles. Thus, any concerns that thermal expansion of nozzle plate 504 may affect nozzle alignment can be alleviated by allowing thermal expansion of the nozzle plate in multiple directions with the above-described configuration.

[0110] In an alternative embodiment, instead of the biasing element 560, a biasing element 860 (having an example configuration described with reference to Figures 8E and 8F) is provided. The biasing element 860 engages with an inclined surface 858 connecting the side 808 and the side 533 of the first end 508. In the example configuration described herein, the biasing element 860 is attached to a slot 857 provided in the upper surface 501 of the base plate 502. The biasing element 860 exerts an elastic force in the direction of arrow 859. The biasing element 860 allows the first end 508 to thermally expand in both the x-axis direction and the y-axis direction away from the position adjustment element 530 (in the directions indicated by arrows 839, 849). When the temperature returns to the ambient or nominal temperature, the first end 508 returns to its original position in both the x-axis direction and the y-axis direction due to the action of the biasing element 860. One or more of the advantages described herein with respect to biasing element 560 may also be achieved by biasing element 860.

[0111] FIG. 8E is a partial top perspective view of the bottom of a print tile showing biasing element 860 for nozzle plates A-C, according to one embodiment. FIG. 8F is a partial cross-sectional view of biasing element 860 of FIG. 8E, according to one embodiment. Here, biasing element 860 for nozzle plate C is described. Biasing elements 860 for nozzle plates A and B are similarly configured. As described with reference to FIG. 8D and shown in FIG. 8E, biasing element 860 is mounted in slot 857 in top surface 501 of base plate 502 and resiliently engages with inclined surface 858 of first end 508 of nozzle plate C. In FIG. 8F, biasing element 860 is a spring clip (e.g., a type of Tinnerman clip). Biasing element 860 has a lower portion 861 that fits into slot 857 by spring force and an upper portion 862 that resiliently engages with inclined surface 858 of first end 508.

[0112] FIG. 9A is a partial top perspective view of the bottom of a printing tile 900 showing the base plate and print head according to one embodiment. FIG. 9B is a schematic cross-sectional view taken along line II-II in FIG. 9A. FIG. 9C is a schematic cross-sectional view taken along line III-III in FIG. 9A. FIG. 9D is a side view and a top view of the mounting element of FIG. 9C according to one embodiment. In one embodiment, the printing tile 900 corresponds to one or more of the printing tiles 202, 302, 500 described herein. Where components in FIG. 9A-9D are shown to have corresponding components in FIG. 5A-5E, the reference numbers in FIG. 5A-5E are increased by 400.

[0113] In FIG. 9A, the print tile 900 includes a base plate 902, a print head 906, and a nozzle plate 904. In some embodiments, the print tile 900 further includes other components as described with reference to FIG. 3. Other print tile configurations are within the scope of various embodiments. Similar to the nozzle plate 504, the individual nozzle plates 904 are shown as nozzle plate A, nozzle plate B, and nozzle plate C. Unless otherwise noted, each nozzle plate 904 is similarly configured to the others. The number of print heads 906 and the corresponding nozzle plates 904 may be other than three. In FIG. 9A, the nozzle plates B and C and the corresponding print heads 906 are omitted to show the features of the other components. The base plate 902 has a top surface 901, a bottom surface 903 opposite the top surface 901 in the thickness direction (e.g., z-axis direction) of the base plate 902, and a number of slots 905 penetrating the base plate 902 from the top surface 901 to the bottom surface 903. In FIG. 9A, the slots 905 for the nozzle plate A are not shown. The top surface 901 of the base plate 902 further includes mounting features 975 (e.g., holes or posts) for mounting to the strength members 350 (see FIG. 3) of the cage 329. The nozzle plates 904 are attached to corresponding print heads 906 and are arranged side by side in the y-axis direction. Each nozzle plate 904 extends along the x-axis direction. Also, each nozzle plate 904 has a first end 908 and a second end 909 located opposite each other. FIG. 9A further shows additional mounting elements 940A, 940B, 940C for the nozzle plates A, B, C. Each of the additional mounting elements 940A, 940B, 940C corresponds to the additional mounting element 540, the conical screw 630, 730A, 730C, or one of the position fixing elements 740A to 740C.

[0114] The printing tile 900 differs from the printing tile 500 in that the base plate 902 incorporates structure for z-axis adjustment and / or θ-y adjustment. Specifically, the first end 908 and the second end 909 of each of the outer nozzle plates A and C are disposed on adjustable elevation parts 981 and fastened to the base plate 902 by first fastening elements 910 and second fastening elements 920, respectively. An example of the configuration of the second fastening elements 920 and the corresponding adjustable elevation parts 981 is described with reference to FIG. 9B. Also shown in FIG. 9A is a hole 983 for each of the nozzle plates A and C to receive the locking set screw of the second fastening element 920. An example of the configuration of the first fastening elements 991 and the corresponding raised pads 982 is described with reference to FIGS. 9C and 9D.

[0115] In one embodiment, the raised pads 982 located under the first and second ends of the nozzle plate B are fixed and the height of the raised pads 982 is not adjustable. In other embodiments, such as those described with reference to Figures 9C and 9D, the height of at least one raised pad 982 is adjustable. In one example, the raised pads 982 are at a height of about 50 microns from the top surface 901 of the base plate 902, and the nozzle plate B defines a coplanar surface with the nozzle plates A and C. The adjustable elevations 981 located under the first and second ends of each of the nozzle plates A and C are adjusted separately from each other and from the other nozzle plate. Such adjustments position the nozzle faces of the print heads attached to the nozzle plates A and C in a coplanar surface with the nozzle faces of the print heads attached to the nozzle plates B. The above configuration is by way of example. Other configurations are within the scope of various embodiments. For example, the raised pads 982 may be raised at a height other than 50 microns relative to the top surface 901 of the base plate 902.

[0116] 9B is a schematic cross-sectional view taken along line II-II in FIG. 9A , showing an example structure of a second fastening element 920 that fastens a second end 909 of the nozzle plate C to the base plate 902. In an embodiment, a first fastening element 910 that fastens a first end 908 of the nozzle plate C to the base plate 902 has the same configuration as the second fastening element 920.

[0117] The second fastening element 920 includes a bolt 921, a nut 928, a differential screw 985, and a locking set screw 990. The bolt 921 extends in the z-axis direction and has a head 922 at its lower end and a thread 923 at its upper end. The head 922 is inserted into a hole 924 in the base plate 902. The bolt 921 extends from the head 922 and passes through a hole 926 in the second end 909 of the nozzle plate C. The thread 923 of the bolt 921 extends beyond the second end 909 and is inserted through a spacer 988 and a washer 989 and engages with the nut 928. The upper surface of the head 922 constitutes an adjustable lifting portion 981. The second end 909 is clamped tightly between the nut 928 and the adjustable lifting portion 981. Lifting the adjustable lift portion 981 by manipulating the differential screw 985 as described herein raises the second end 909 along with the adjustable lift portion 981. This provides z-axis adjustment and / or theta-y adjustment.

[0118] The differential screw 985 is inserted into a hole opening in the lower surface 903 of the base plate 902. The differential screw 985 has a first thread 986 and a second thread 987. The first thread 986 engages with a corresponding thread cut in a hole in the base plate 902. The second thread 987 engages with a corresponding thread cut in the head 922 of the bolt 921. A first thread pitch Pitch1 of the first thread 986 is different from a second thread pitch Pitch2 of the second thread 987. The effective pitch of the differential screw 985 is equal to Pitch1 minus Pitch2. When the differential screw 985 rotates, for example, clockwise, the adjustable lifting portion 981 lifts by an amount corresponding to the amount of rotation and the effective pitch. In one example, the diameter of the first thread 986 is 3 mm, and the first thread pitch Pitch1 is 0.5 mm. The second thread 987 has a diameter of 2.5 mm and a second thread pitch Pitch2 of 0.45 mm. One revolution of the differential screw 985 raises the adjustable lift section 981 and the second end 909 of the nozzle plate C by 50 microns. A quarter revolution raises or lowers the second end 909 of the nozzle plate C by 12.5 microns. This configuration allows all nozzle faces 978 to be coplanar to within a few microns. Once coplanarity is achieved, a locking set screw 990 accessible through a hole 983 is manipulated to contact the differential screw 985 (shown at 984) to lock the differential screw 985 in the adjusted position. The specific thread pitch and / or dimensions described above are exemplary. Other configurations are within the scope of various embodiments. For example, Pitch1 and Pitch2 can be varied to reduce the effective pitch of the differential screw 985. In that case, the amount of adjustment per revolution of the differential screw 985 can be reduced.

[0119] 9C is a schematic cross-sectional view taken along line III-III in FIG. 9A, and shows an example of the structure of a first fastening element 991 that fastens a first end 908 of the nozzle plate B to the base plate 902. A second fastening element 992 that fastens a second end 909 of the nozzle plate B to the base plate 902 has the same configuration as the first fastening element 991.

[0120] The first fastening element 991 includes a bolt 993, a nut 968, and a locking set screw 964. The bolt 993 is shown in side and top views in FIG. 9D. As shown in FIG. 9D, the bolt 993 includes a first thread 994 at a lower end, a second thread 995 at an upper end, and a support 996 between the first thread 994 and the second thread 995. A washer 997 is disposed on the support 996 so as to surround the bolt 993. The upper surface of the washer 997 constitutes the raised pad 982. In some embodiments, the washer 997 may not be provided. In that case, the support 996 itself constitutes the raised pad 982. Another washer 998 is also provided so as to surround the second thread 995 of the bolt 993. In one embodiment, one or more of the washers 989, 997, 998 are made of PEEK to allow for sliding due to thermal expansion of the corresponding nozzle plate. Washers made of other materials are within the scope of various embodiments. The top view of Figure 9D shows an engagement portion 999 on the top of the bolt 993. The engagement portion 999 engages a tool to rotate the bolt 993 to adjust the height of the raised pad 982.

[0121] As shown in FIG. 9C, the bolt 993 is inserted into the blind hole 963. The blind hole 963 has an extension near the top surface 901 of the base plate 902. The extension defines a flange 966. A first thread 994 of the bolt 993 engages a corresponding thread in the hole 963 in the base plate 902. A washer 997 on the support 996 protrudes in the z-axis direction beyond the top surface 901 of the base plate 902 to define a raised pad 982. The bolt 993 extends in the z-axis direction through and beyond the hole 916 in the first end 908. A second thread 995 of the bolt 993 extends beyond the first end 908. A washer 998 and a spacer 967 are positioned to surround the second thread 995, which is fastened to a nut 968. A first end 908 of the nozzle plate is clamped between a washer 998 below the nut 968 and a washer 997 on the support 996. The torque of the nut 968 is controlled so as to secure the nozzle plate between the washers 998, 997, while not preventing the nozzle plate from sliding due to thermal expansion.

[0122] The raised height of the raised pad 982 in the z-axis direction can be individually adjusted based on the thickness of the washer 997 and / or the depth to which the bolt 993 is threaded into the hole 963. When the bolt 993 is fastened into the hole 963, the support 996 may rest on the flange 966. The position at which the support 996 rests on the flange 966 corresponds to the minimum height that the raised pad 982 can be. The bolt 993 may be positioned such that the support 996 does not rest on the flange 966. In one example, the first thread 994 of the bolt 993 has a diameter of 4 mm and a thread pitch of 0.25 mm. One rotation of the bolt 993 raises or lowers the support 996, raised pad 982, and the first end 908 of the nozzle plate by 250 microns. Once the raised pads 982 are adjusted to the desired height, locking set screws 964 accessible through holes (not numbered) in the sides of the base plate 902 are manipulated to contact and lock the bolts 993, thereby locking the corresponding raised pads 982 at the desired raised height. The specific thread pitch and / or dimensions discussed above are examples. Other configurations are within the scope of various embodiments.

[0123] In one configuration, adjustable raised pads 982, as described with reference to Figures 9C and 9D, are positioned below the first and second ends of each nozzle plate, respectively. The height of each raised pad 982 is adjusted independently of the other raised pads 982 by rotating bolts 993 with a tool engaging engagement portion 999. This adjustment is made so that the nozzle faces of the printheads are coplanar, or nearly coplanar to within 50 microns. Once coplanarity is achieved, the corresponding locking set screws 964 are manipulated to lock the raised pads 982 to maintain the coplanar nozzle faces. In an alternative configuration, adjustable elevation portions 981, as described with reference to Figure 9B, are positioned below the first and second ends of each nozzle plate, respectively. In another configuration, both one or more adjustable raised portions 981 and one or more raised pads 982 (which may be fixed or adjustable) are provided on the same printing tile for use in aligning the printheads and / or nozzles.

[0124] In one example of a print head and / or nozzle alignment process in a print tile, the nozzle faces are first aligned using spacers and / or adjustable lifts and / or raised pads as described with reference to Figures 5C-5E and 9A-9D to make z-axis and / or θ-y adjustments to make the nozzle faces coplanar. The print heads are then aligned using the alignment elements or cone screws as described with reference to Figures 5B, 5D, 6A-6D to make the print heads parallel. An x-axis adjustment is then optionally made using the alignment elements or cone screws as described with reference to Figures 7A and 7B. The fastening elements are fastened to maintain the resulting coplanarity of the nozzle faces, the parallelism of the print heads, and / or the x-axis accuracy of the print heads. In one embodiment, the fastened print heads are allowed to thermally expand at least at one end as described with reference to Figures 8A-8F. This ensures that temperature variations during operation do not significantly affect the aligned print heads and / or nozzles. The specific order of adjustments described above is merely exemplary. Adjustments may be made in other orders in one or more of the six directions mentioned above (i.e., x-axis, y-axis, z-axis, θ-x, θ-y, θ-z) and such adjustments are within the scope of various embodiments.

[0125] When the printheads and / or nozzles of each printing tile are properly aligned as described above and the tiles are assembled into the printhead assembly so that they have a common mounting surface (see FIG. 4B), the alignment of the printheads and / or nozzles can be maintained throughout the printhead assembly.

[0126] Figure 10A is a perspective view of an upper portion of a printing tile 302 and a corresponding connector portion of a feeding mechanism 428 that is mated to the printing tile 302, according to one embodiment. Figures 10B-10E are schematic cross-sectional views illustrating various conditions for mating the upper portion of the printing tile 302 with a corresponding connector portion of the feeding mechanism 428. The structures and / or connections described with reference to Figures 10A-10E correspond to region 411 of Figure 4A.

[0127] 10A to 10E, the end plate 362 of the printing tile 302 is provided with a protective wall 363. The protective wall 363 surrounds the fluid connectors 380, 382, ​​the alignment holes 384, 386, and the screw hole 388 (see FIG. 3). The fluid connectors 380, 382, ​​the alignment holes 384, 386, and the screw hole 388 are not shown in FIG. 10A, but are shown and described in FIGS. 10B to 10E. The protective wall 363 forms a reservoir for collecting printing material that leaks out when the printing tile 302 is disconnected from the supply mechanism 428. The end plate 362 further includes an electronics opening 390 as described with reference to FIG. 3, and an electronic connector 1060 exposed from the electronics opening 390. The electronic connector 1060 is coupled to or is part of the electronic interface member 360 as described with reference to FIG. 3. The electronic connector 1060 and the fluid connectors 380, 382 form a connector set for the printing tile 302 through which the printing material supply, electrical supply, and control for the printheads of the printing tile 302 are provided.

[0128] The feed mechanism 428 includes a corresponding connector set that is coupled to the connector set of the end plate 362. For example, the connector set of the feed mechanism 428 includes, for each print tile 302, an electronic connector 1040 that is electrically coupled to the electronic connector 1060 of the print tile 302, and fluid connectors 1080, 1082 (see FIGS. 10B-10E ) that are fluidly coupled to corresponding fluid connectors 380, 382 of the print tile 302. The feed mechanism 428 further includes alignment pins 1084, 1086 that are aligned and inserted into alignment holes 384, 386 of the print tile 302, and a threaded connector 1088 (e.g., a thumb screw) that is threadedly coupled to a threaded hole 388 of the print tile 302. The alignment pins 1084, 1086 and the corresponding alignment holes 384, 386 together form an alignment structure. In an alternative arrangement, one or more alignment holes are provided in the feeding mechanism 428 and one or more corresponding alignment pins are provided in the end plate 362. The threaded connector 1088 and the threaded holes 388 together form a fastening structure. The alignment and fastening structures allow the printing tiles 302 to be removably attached to the feeding mechanism 428 from below with a blind connection. Other configurations for the alignment and / or fastening structures are within the scope of various embodiments.

[0129] 10B-10E are schematic cross-sectional views illustrating various states during the connection process between the top of the print tile 302 and the corresponding connector portion of the delivery mechanism 428. For simplicity, the electronic connectors 1040, 1060 are omitted from FIG. 10B-10E. In one embodiment, the fluid connectors 1080, 1082 and the fluid connectors 380, 382 are brought close together to align, make an initial connection, and then fully connect. At the same time, the electronic connectors 1040, 1060 are also brought close together to align, make an initial connection, and then fully connect.

[0130] FIG. 10B shows the beginning of the connection process, in which the printing tile 302 is lifted from below and brought closer to the supply mechanism 428. FIG. 10B further shows the conduits 1011, 1013 coupled to the fluid connectors 1080, 1082. Once the connection is complete, the printing material can be supplied and returned through the conduits 1011, 1013. The supply mechanism 428 further includes a recess 1063. The recess 1063 surrounds the fluid connectors 1080, 1082, the alignment pins 1084, 1086, and the threaded connector 1088. The aspect is similar to the protective wall 363 surrounding the fluid connectors 380, 382, ​​the alignment holes 384, 386, and the threaded hole 388. The printing tile 302 further includes a seal ring 1010, 1012 surrounding the corresponding fluid connectors 380, 382.

[0131] 10C illustrates the next stage in the connection process, where the print tile 302 is brought closer to the feeding mechanism 428. At this stage, the threaded connector 1088 begins to be partially inserted into the threaded hole 388, but is not yet threaded into the threaded hole 388.

[0132] 10D illustrates the next stage of the connection process, where the print tile 302 is brought closer to the feeding mechanism 428. In this stage, the threaded connector 1088 is threaded into the threaded hole 388. In one embodiment, the threaded connector 1088 can be manipulated from above with a tool (not shown). The tool engages the threaded connector 1088 and rotates it, threading it further into the threaded hole 388. As the threaded connector 1088 rotates, the print tile 302 is drawn toward the feeding mechanism 428. The alignment pins 1084, 1086 align with the corresponding alignment holes 384, 386 and gradually move into these holes 384, 386. The alignment pins 1084, 1086 are tapered at their lower ends, and the upper openings of the alignment holes 384, 386 are flared upward. This shape allows the alignment pins 1084, 1086 to easily align with and enter the corresponding alignment holes 384, 386. When the alignment pins 1084, 1086 are inserted into the corresponding alignment holes 384, 386, the fluid connectors 1080, 1082 are aligned with the fluid connectors 380, 382, ​​and the recesses 1063 are aligned with the protective wall 363.

[0133] FIG. 10E shows the final stage where the connections are complete. In FIG. 10E, the threaded connector 1088 and threaded holes 388 are not shown (omitted). The alignment pins 1084, 1086 are fully inserted into the corresponding alignment holes 384, 386. The fluid connector 1080 is mated to the fluid connector 380, with a seal ring 1010 surrounding the mated fluid connectors 1080, 380 to seal against leakage. Similarly, the fluid connector 1082 is mated to the fluid connector 382, ​​with a seal ring 1012 surrounding the mated fluid connectors 1082, 382 to seal against leakage. This allows the conduits 1011, 1013 to be fluid-tightly mated to the corresponding conduits 310, 312 to supply and return printing material to and from the print heads of the connected printing tiles 302. A protective wall 363 is inserted into the recess 1063, which further provides a seal to prevent leakage and / or foreign matter around the fluid connection. Although not shown in FIG. 10E, the electronic connectors 1040, 1060 are also fully connected at this final stage. The connected printing tiles 302 can be removed in reverse for repair or replacement.

[0134] Figure 11A is a bottom view of a printhead assembly 1100 according to one embodiment, showing an array of printheads 1110. In an embodiment, the printhead assembly 1100 and array 1110 correspond to one or more of the printhead assemblies and arrays of printheads described with reference to Figures 1, 2, 4A, and 4B.

[0135] The array 1110 includes a plurality of print tiles 1102 print heads. Each print tile 1102 includes a plurality of print heads 1104. In an embodiment, the print tiles 1102 and print heads 1104 correspond to one or more of the print tiles and print heads described with reference to FIGS. 2 to 10E. In each print tile 1102, the print heads 1104 are attached to the base plate 1103 via a corresponding nozzle plate. As described herein, the print heads and nozzle plates are aligned with each other and / or with respect to the base plate in one or more translational directions along the x-axis, y-axis, z-axis, and / or in one or more rotational directions θ-x, θ-y, θ-z. As described with reference to FIGS. 4A, 4B, 10A to 10E, each print tile 1102 is inserted and pressed into a corresponding hole in the support plate 422 with the print heads 1104 aligned and fastened to connect to the feed mechanism 428. When the printing tile 1102 is connected, the base plate 1103 is supported on the lower surface 483 of the support plate 422 .

[0136] The print tiles 1102 are arranged in multiple rows, and in the example configuration of FIG. 11A, different rows are configured to deposit different print materials. For example, in FIG. 11A, the print heads in the top two rows 1111 deposit a first print material, the print heads in the middle two rows 1112 deposit a second print material, and the print heads in the bottom two rows 1113 deposit a third print material. Other arrangements for depositing the same or different print materials may be used and are within the scope of various embodiments. The print tiles 1102 and print heads 1104 in adjacent rows are staggered. The print tiles 1102 and print heads 1104 in each row are aligned along the x-axis direction using a tool 1120 (e.g., a plate or card) with a known straight edge 1121. As shown in FIG. 11A, the straight edge 1121 can be applied to the edge of an adjacent print tile in the same row to ensure that the print tiles in that row are aligned along the x-axis direction. The print heads 1104 in each printing tile 1102 are already aligned with respect to each other and to the printing tile base plate, so that the positions of all the print heads 1104 in each row, and therefore the entire array 1110, are aligned within a given tolerance range. In one example, the x-axis positions of all the nozzles in a printing tile are aligned to within 100 μm, the y-axis positions are determined by machining tolerances, the z-axis positions of all the nozzles in a printing tile are aligned to within 100 μm, the θ-z positions of the print heads on the printing tile are aligned to within 20 μrad in the x-axis direction, the x-axis and y-axis positions of all the printing tiles in a printhead assembly are aligned to within 1 mm, and the z-axis positions of all the printing tiles in a printhead assembly are aligned to within 100 μm.

[0137] Figure 11B is an expanded view of region 1130 of Figure 11A, showing the overlap of nozzles of adjacent printheads 1134, 1144 in printed tiles 1132, 1142 of adjacent columns 1111. The overlap d is the distance along the x-axis between the right-most nozzle 1136 of printhead 1134 and the left-most nozzle 1146 of printhead 1144. In one embodiment, the overlap d is between 0.91 mm and 1.12 mm.

[0138] While embodiments in accordance with one or more aspects of the present invention have been described above, other embodiments not specifically described in this disclosure may be devised without departing from the basic scope of the disclosure, which scope is defined by the following claims.

Claims

1. In a printing tile for a print head assembly of a printer, a base plate having an upper surface, a lower surface opposite to the upper surface in a thickness direction of the base plate, and a slot penetrating the base plate from the upper surface to the lower surface; a printhead having a lower portion disposed within the slot, the printhead having a plurality of nozzles disposed in the lower portion for ejecting a printing material during a printing operation; a nozzle plate attached to the printhead; a plurality of mounting elements for mounting the nozzle plate to the base plate while allowing adjustment of the position of the printhead relative to the base plate; Equipped with the nozzle plate having opposed first and second ends; A printing tile, wherein the base plate has first and second adjustable lifting portions below the first and second ends of the nozzle plate, respectively, and the lifting portions separately adjust the positions of the first and second ends of the nozzle plate in the thickness direction of the base plate.

2. The printing tile of claim 1 , wherein the plurality of mounting elements includes first and second fastening elements that fasten the first and second ends of the nozzle plate to the base plate, respectively.

3. Further comprising a spacer having a predetermined thickness; The printing tile of claim 2 , wherein the spacer is disposed between the top surface of the base plate and the first end or the second end of the nozzle plate.

4. Further comprising a plurality of spacers having different predetermined thicknesses; a first spacer of the plurality of spacers is disposed around the first fastening element between the first end of the nozzle plate and the top surface of the base plate; The printing tile of claim 2 , wherein a second spacer of the plurality of spacers is disposed about the second fastening element between the second end of the nozzle plate and the top surface of the base plate.

5. The plurality of mounting elements further includes a position adjustment element; The printing tile according to claim 2 , wherein the position adjustment element engages with a side surface of the nozzle plate to adjust the position of the nozzle plate in a rotational direction about an axis along the thickness direction of the base plate.

6. the plurality of mounting elements further comprising a conical thread; 3. The printing tile of claim 2, wherein the conical surface of the conical screw engages with the first end of the nozzle plate to adjust the position of the first end in a rotational direction, the rotational direction being a rotational direction about an axis located at the second end of the nozzle plate and aligned along the thickness direction of the base plate.

7. the plurality of mounting elements further including a biasing element engaging the first end of the nozzle plate; The first fastening element is disposed between the conical thread and the biasing element; The printing tile of claim 6 , wherein the biasing element resiliently biases the first end of the nozzle plate toward the conical thread.

8. the plurality of mounting elements further including another mounting element that engages the first end of the nozzle plate; The printing tile of claim 6 , wherein the first fastening element is disposed between the conical thread and the further mounting element.

9. The plurality of mounting elements further include a position fixing element or a position adjustment element, 3. The printing tile of claim 2, wherein the position fixing element or the position adjustment element engages with the second end of the nozzle plate so as to fix or adjustably fix the position of the second end in the longitudinal direction while allowing the position of the first end of the nozzle plate to change in the longitudinal direction of the nozzle plate due to thermal expansion of the nozzle plate.

10. The plurality of mounting elements further includes a wave washer surrounding the first fastening element, the wave washer is disposed between the first end of the nozzle plate and a nut or head of the first fastening element; The printing tile of claim 9 , wherein the wave washer secures the first end of the nozzle plate to the base plate while allowing for thermal expansion of the nozzle plate.

11. The printing tile of claim 9 , wherein the second end of the nozzle plate has a notch in which the position fixing element or the position adjustment element is disposed.

12. the slot is a first slot, the printhead is a first printhead, the nozzle plate is a first nozzle plate, the plurality of nozzles is a first plurality of nozzles, and the printing tile further comprises: a second slot extending through the base plate; a second printhead having a lower portion disposed within the second slot, the second printhead having a second plurality of nozzles disposed at the lower portion for ejecting the printing material during the printing operation; a second nozzle plate attached to the second printhead and the base plate; Equipped with the second nozzle plate having opposed first and second ends; the base plate further includes a first pad disposed between the first end of the second nozzle plate and the base plate, and a second pad disposed between the second end of the second nozzle plate and the base plate, 2. The printing tile of claim 1, wherein the first and second adjustable lift sections are adjustable to align the first nozzle plate and the first printhead with the second nozzle plate and the second printhead over the first and second pads.

13. At least one of the first and second adjustable lift sections includes a differential screw; the differential screw has a first thread that engages with the base plate and a second thread that engages with a head of the first fastening element; a first thread pitch of the first thread is different from a second thread pitch of the second thread; The printing tile of claim 1 , wherein the head of the first fastening element engages the first end from below.

14. The first or second fastening element is a first thread engaging the base plate; a second thread that engages the nut; and a support portion disposed between the first thread and the second thread, the support portion including a raised pad; having The printing tile of claim 1 , wherein the corresponding first or second end of the nozzle plate is fastened between the support and the nut.

15. In a printing tile for a print head assembly of a printer, a base plate having an upper surface, a lower surface opposite to the upper surface in a thickness direction of the base plate, and a plurality of slots penetrating the base plate from the upper surface to the lower surface; a plurality of print heads, each print head having a lower portion disposed within a corresponding one of the plurality of slots and each print head having a plurality of nozzles disposed on the lower portion for ejecting printing material during a printing operation; a plurality of nozzle plates, each nozzle plate attached to a corresponding one of the plurality of printheads, each nozzle plate having opposed first and second ends; a plurality of mounting elements for mounting the plurality of nozzle plates to the base plate; Equipped with The plurality of mounting elements, for each nozzle plate of the plurality of nozzle plates, a first fastening element fastening the first end of the nozzle plate to the base plate, and a second fastening element fastening the second end of the nozzle plate to the base plate; Cone thread and Including, A printing tile, wherein the conical surface of the conical screw engages with the first end of the nozzle plate to adjust the position of the first end in a rotational direction, the rotational direction being a rotational direction about an axis located at the second end of the nozzle plate and aligned along the thickness direction of the base plate.

16. For each nozzle plate of the plurality of nozzle plates, the plurality of mounting elements further including a biasing element configured to resiliently bias the first end of the nozzle plate toward the conical thread; The printing tile of claim 15 , wherein the first fastening element is disposed between the conical thread and the biasing element.

17. For each nozzle plate of the plurality of nozzle plates, the second end of the nozzle plate has a notch, the side walls of the notch being tapered such that the distance between the side walls decreases from the second end to the first end of the nozzle plate in a longitudinal direction of the nozzle plate; a screw hole exposed through the notch is provided on the upper surface of the base plate; The plurality of attachment elements further include: a position fixing pin that is removably disposed in the screw hole so as to engage with the side wall of the notch and that fixes the position of the second end of the nozzle plate in the longitudinal direction and in a lateral direction intersecting the longitudinal direction; or 16. The printing tile of claim 15, including another conical screw removably screwed into the threaded hole to engage the side wall of the notch and adjustably fix the position of the second end of the nozzle plate in the longitudinal and lateral directions.

18. For each nozzle plate of the plurality of nozzle plates, the nozzle plate is unconstrained in the longitudinal direction away from the notch; or 18. The printing tile of claim 17, wherein the plurality of mounting elements further includes a wave washer surrounding the first fastening element, the wave washer being positioned between the first end of the nozzle plate and a nut or head of the first fastening element to accommodate thermal expansion of the nozzle plate.

19. in at least one nozzle plate of the plurality of nozzle plates, the first and second fastening elements are disposed on corresponding raised pads on the top surface of the base plate; The printing tile of claim 15, wherein in at least one other nozzle plate of the plurality of nozzle plates, the first and second fastening elements are arranged on corresponding adjustable elevation portions to separately adjust the positions of the first and second ends in the thickness direction of the base plate.

20. In a printhead assembly for an inkjet printer, Housing and a feed mechanism supported on an upper portion of the housing; a plurality of printing tiles removably supported on a lower portion of the housing; Equipped with Each of the plurality of print tiles comprises: a base plate having a plurality of slots; a plurality of printheads, each printhead being partially inserted into a corresponding one of the plurality of slots and each printhead having a plurality of nozzles for ejecting printing material during a printing operation; a plurality of nozzle plates attached corresponding to the plurality of print heads; a plurality of mounting elements adjustably fastening the plurality of nozzle plates to the base plate; a connector set disposed above the plurality of printheads, the connector set comprising at least one fluid connector fluidly coupled to the plurality of printheads and at least one electrical connector electrically coupled to the plurality of printheads; Equipped with the feed mechanism includes a mating connector set for each of the plurality of printing tiles, the mating connector set being coupled to the connector set of the printing tile when the printing tile is removably attached to the feed mechanism from below by a fastening structure and an alignment structure; The alignment structure comprises: at least one alignment pin on one of the feed mechanism and the printing tile; at least one alignment hole in the other of the feed mechanism and the printing tile; Equipped with The at least one alignment pin is aligned and inserted into the at least one alignment hole.

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