One-sided mounting of S-shaped print head

Abstract

Techniques and manufacturing schemes are described that allow multiple printheads to be mounted side-by-side to create a consistent single line width print swath suitable for at least single pass and wide format scanning printers.

Description

[Technical Field]

[0001] (Related Applications) This application claims priority to co-pending U.S. patent application Ser. No. 17 / 931,850, filed Sep. 13, 2022, the entire contents of which are incorporated herein by reference.

[0002] The innovation relates generally to the field of printheads. More specifically, the innovation relates to a method and device for a single-sided mounting device and process that allows a mounting support to hold an S-shaped printhead from one side of the printhead. [Background technology]

[0003] Inkjet printing is a printing method that reproduces digital images by depositing droplets of ink onto substrates such as paper and plastic. Many modern inkjet printers use drop-on-demand (DOD) technology to expel ink droplets from a reservoir through a nozzle onto the substrate. Therefore, the mounting and positioning of components, particularly the reservoir and nozzle, is critical to accurately depositing ink at the desired location. These components together form the printhead, also known as the printhead assembly or print beam.

[0004] To ensure high quality printing, it is desirable for the print head to be accurately positioned above the substrate being printed on. Print head placement and mounting are critical elements of an inkjet printer. Even small errors can degrade print quality, especially when multiple sources of error combine to adversely affect the placement of droplets on the substrate.

[0005] The physical position of a printhead is typically controlled by tightly toleranced machined parts, adjustment mechanisms, or both. Printheads have precise surfaces called reference or datum surfaces. A reference surface is a surface on the printhead body that is precisely positioned relative to the printhead nozzles. Reference surfaces are used to precisely position the printhead within the printing device, ensuring that the printhead reference contacts an equally precise feature on the printing device (the reference surface on the printing device). Two or more reference surfaces are required for each printhead, and these are manufactured into the printhead body by the printhead manufacturer. Printhead references are known to require very tight tolerances for nozzle positioning. The tolerance of the printhead reference surface relative to the printhead nozzles is a few microns (typically + / - 5µ to + / - 10µ). The printer can achieve precise nozzle positioning using tightly toleranced machined parts, adjustment mechanisms, or a combination of both. The precision with which printheads are positioned varies depending on the application. A tolerance of + / - 10µ is typically required for high-quality printing. This value is a combination of the printhead reference surface tolerance and the printing device reference surface tolerance.

[0006] Each printhead has a limited number of nozzles that eject ink to form a single droplet on the substrate. To print on wide substrates or to increase productivity, multiple printheads are used to create a wider array of nozzles than is usually possible with a single printhead.

[0007] Due to mechanical constraints, printing wide substrates using multiple printheads is typically achieved by overlapping each printhead with the next in a brick-like fashion, a method widely adopted in the industry that requires a lot of space due to the staggered layout.

[0008] Printhead suppliers have designed S-shaped printheads to enable interlocking printheads without the need for the aforementioned brick-like or staggered layouts where each printhead overlaps the next. S-shaped printheads achieve continuous printing by overlapping one printhead with the next without any staggering. This configuration allows for a much more compact printer. The standard mounting method for a typical printhead is to attach it to a flat surface (hereafter referred to as a jet plate) using mounting screws or an equivalent attachment mechanism located on both sides of the printhead. However, for example, in a multiple S-shaped printhead design where no gaps in the continuous line of nozzles or very little gap between printheads are desired, the resulting part (e.g., jet plate) to which the printheads are attached must be hollow along the entire length of the printing array to accommodate or accommodate multiple S-shaped printheads. The brick-like printhead flat surface (also called a jet plate or plate) 101 is provided with strength by a certain amount of material between one hole 104 and the next hole 104. In contrast, the jet plate 201 of an S-shaped printhead has a series of holes (e.g., the hole shown between 205 and 206) that span the entire printhead array. This series of holes weakens the plate. The hollow features in the jet plate 201 can be considered an inherent result of the S-shaped printhead design. It should be understood that, according to some embodiments herein, plates 101 and 201 are designed or provided by the printer manufacturer (e.g., Electronics for Imaging, Inc. ("EFI") of Fremont, California) rather than being provided by the printhead manufacturer.

[0009] It has been found that short arrays of S-shaped printheads can be mounted using standard mounting techniques. As an example, three to four printheads each are short arrays that can be mounted using an approach similar to that shown in Figure 2. However, as arrays become longer, the strength and manufacturing precision of the resulting plate become insufficient. For example, typical long arrays include six printheads for large scanning machines, 15 printheads for very large scanning machines, 20 printheads for small single-pass machines, and up to 50 printheads for very wide single-pass machines. As previously mentioned, because there is little clearance left between one printhead and the next, the mounting supports to accommodate such long arrays would be hollow and weak, and there may be no material connecting the two sides (e.g., 205 and 206 in Figure 2). As shown in Figure 2, the jet plate 201 for an S-shaped printhead can be thought of as two long, parallel beams (e.g., 205 and 206) with no material between them.

[0010] This presents industrial printer manufacturers with two problems. First, due to the inherent constraint that the two sides of the mount support are not connected, the mount support of an S-shaped printhead weakens as the number of mounted printheads increases. Second, the tight-tolerance machined parts (herein referred to as reference surfaces) that are manufactured or attached to the mount support and that help accurately position each printhead cannot be manufactured to the required tolerances due to the weak mount support. Summary of the Invention

[0011] The disclosed embodiments include a method for mounting an S-shaped printhead using one side of the printhead, which allows for the production of a stronger mounting support that overcomes at least the problems and shortcomings presented by standard mounting methods.

[0012] One of the disclosed methods allows access to one side of the print head, i.e., the side not attached to the mount support, for maintenance and assembly.

[0013] One disclosed mounting method involves a mechanical component (also referred to herein as a brace) attached to the printhead. Such a brace can be attached to the printhead with screws, using mounting points on the printhead frame or new mounting points manufactured into the printhead frame and / or other parts of the printhead.

[0014] The brace can be designed to mount the printhead to the face of the printer in either or both horizontal and vertical planes, and to hold the printhead to the printer.

[0015] Such braces may be attached to the printhead using adhesives, screws, or other attachment means conventional in the industry, which may include nails, bolts, removable clips, loop and hook fasteners, adhesives, or other suitable fasteners.

[0016] Such a brace can include new reference surfaces on the printhead that are precisely positioned relative to the print nozzles. The original reference surfaces on the printhead are designed by the printhead manufacturer, which limits the way the printhead can be mounted to a flat surface. By attaching a brace to the printhead, the printer manufacturer can replace some or all of the original reference surfaces and position them as needed.

[0017] The new reference can be positioned by optical or mechanical alignment to tolerances exceeding those of the original printhead and in a location more suitable for the mounting scheme disclosed herein.

[0018] This summary is provided to introduce a selection of concepts in a simplified form that are further described in the detailed description. This summary is not intended to be used to limit the scope of the claimed subject matter. Other aspects of the disclosed embodiments will become apparent from the accompanying figures and detailed description. [Brief explanation of the drawings]

[0019] The technology presented herein can be better understood by reference to the following detailed description in conjunction with the accompanying drawings, in which like reference numbers indicate identical or functionally similar elements.

[0020] [Figure 1] 1 is a schematic diagram showing an example of an array of brick-shaped printheads stacked and mounted in a staggered arrangement like bricks, according to the prior art; [Figure 2] FIG. 1 is a schematic diagram showing a standard mount for an array of S-shaped printheads according to the prior art. [Figure 3] FIG. 1 is a schematic diagram showing an array of S-shaped printheads viewed from above, according to the prior art. [Figure 4] FIG. 10 is a schematic diagram illustrating an example of a brace attached to one side of a print head, according to one embodiment. [Figure 5] FIG. 10 is a schematic diagram illustrating an example of an array of S-shaped printheads, each assembled with a respective brace, according to one embodiment. [Figure 6A] 1A-1C are schematic diagrams illustrating examples of different mounting schemes using braces, according to one embodiment. [Figure 6B] 1A-1C are schematic diagrams illustrating examples of different mounting schemes using braces, according to one embodiment. [Figure 6C] 1A-1C are schematic diagrams illustrating examples of different mounting schemes using braces, according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] Inkjet printing is a printing method that reproduces digital images by depositing droplets of ink on a substrate such as paper, plastic, or textile. Many modern inkjet printers use drop-on-demand (DOD) technology to expel droplets of ink from a reservoir through a nozzle onto the substrate. The device used to implement DOD technology is called a printhead.

[0022] A printhead includes a frame made of multiple materials and components that houses electronics, an inking system, and nozzles. The electronics drive the nozzles, while the inking system delivers ink to the nozzles. The ink is delivered from the nozzles as droplets to a target substrate, forming dots that form the printed image. Each droplet can be thought of as a pixel on the substrate. Therefore, the position of a nozzle relative to other nozzles on the printhead, relative to the substrate, and relative to nozzles on other printheads must be precise within a few microns of tolerance. This becomes important when multiple printheads are used per color.

[0023] In recent years, one of the main development goals has been to increase productivity. Productivity is measured in square meters that a printer can print in a certain amount of time. One way to increase productivity is to use multiple printheads per color. A printhead is much like a paintbrush: two or more printheads assembled precisely side-by-side result in a wider stroke, and therefore increased productivity. Another reason for increasing the number of printheads per color is to print wider substrates in single-pass applications, where the printable width is the combined width of the printheads.

[0024] Two types of inkjet printheads are discussed here: brick-type and S-type.

[0025] Brick-shaped printheads do not interlock with one another. Assembling multiple color printheads requires staggering the brick-shaped printheads. Figure 1 shows an example of a prior art brick-shaped printhead mounted on top of another brick. Each printhead 103 has a limited number of nozzles 102. To print wide substrates or increase productivity, multiple printheads are used to create wider nozzle lines than are possible with a single printhead. The mounting support can be a flat plate 101 with staggered holes 104 and mounting features (not shown) that allow the printheads to be precisely positioned relative to one another within tolerances. Mounting features include, but are not limited to, tightly toleranced machined parts that serve as reference surfaces, precisely located pins that serve as reference surfaces, alignment features that allow the printheads to be moved precisely (within acceptable tolerances) to the correct position, and combinations of the above. When brick-shaped printheads are staggered, the overall width 105 of the mounting support 101 is greater than what can be achieved with an S-shaped printhead. Such an overall width would adversely affect machine performance, affecting cost, productivity, and quality, however the mount support 101 is strong and can accommodate a variety of printheads without flexing.

[0026] S-shaped printheads can be designed by printhead manufacturers to form continuous lines without interlocking with each other. S-shaped printheads create continuous printing by allowing one printhead to overlap the next without shifting. This allows for much more compact printers.

[0027] Figure 2 shows an example of a standard mount for an array of S-shaped printheads according to the prior art. Each printhead 203 overlaps the next printhead with its S-shape. The nozzles 202 form a continuous line without the need for offsetting the printheads. The resulting mount support 201 can be made much narrower than a brick-type printhead support, but it is much more difficult to manufacture and has proven to be structurally less stable. Because the geometry used to support a line of S-shaped printheads is unique, using such a design for wider print arrays has proven problematic and sometimes impossible. The mount support structure weakens as the number of printheads aligned increases, and beyond a certain number of printheads, such a structure becomes too weak to support. For example, such a mount configuration has proven unsuitable for print widths of more than two printheads. Structurally, a single continuous line of nozzles weakens the reliability of the mount support or jet plate, leading to problems with bending and instability of the mount support. For much the same reason, jet plates have proven difficult to manufacture to precise tolerances, as the structure would be too weak and hollow to be accurately manufactured.

[0028] 3 shows a top view of a prior art array of S-shaped printheads 301. Standard mount attachment points 302 and 303 are on opposite sides of printhead 301. Because mount support 304 does not have the space to cross or otherwise support the printhead array, the resulting mount support 304 can be hollow and weak.

[0029] The present invention proposes a method and apparatus that enables or provides a compact and structurally stable mounting support by using one side of an S-shaped printhead (such as a commercially available S-shaped printhead) to hold the printhead to the printer body. This innovation is achieved by attaching a novel part (called or referred to as a brace) to the printhead, which effectively relocates (or effectively reassigns or replaces) the original mounting points 302 and 303 to new mounting points on the part or brace itself.

[0030] In one embodiment, the brace is configured to abut the S-shaped printhead and abut the mount support, thereby securing the S-shaped printhead to a single mounting point.

[0031] One embodiment can be understood with reference to FIG. 4, which is a schematic diagram illustrating an example of a brace 405 attached to one side of a print head 401. In this embodiment, the brace 405 is attached to the print head 401 by a screw 404. In one embodiment, the screw 404 has two or more threads. According to embodiments herein, two or more screws are sufficient to secure the brace 405 in place. In another embodiment, a combination of a single screw and a mechanism to prevent the brace from rotating also works. Examples include a screw and pin or a screw and bayonet mount. The original attachment point 407 remains unused. New attachment points 403 and 406 are located on the brace 405 and allow the print head 401 to be held to one side. The shape and attachment method of the brace 405 are not limited to this embodiment. The brace 405 may be attached in different ways, such as, but not limited to, using adhesive on the side of the print head. Other attachment methods include using screws, pins, or clamps that tighten around the print head. The shape of brace 405 may be tailored to suit the particular application and shape of the mounting support. Examples of different shapes are shown in part 603 of Figures 6A-C.

[0032] Embodiments can be understood with reference to Figures 6A-C. Figure 5 is a schematic diagram illustrating an example of an array of S-shaped printheads 503, each printhead combined with a respective brace 502 of the present invention. In this embodiment, the mounting support is a T-shaped beam 501. By allowing the mounting support to hold each printhead 503 on only one side of each printhead 503, the strength of the mounting support 501 is independent of the length of the array of heads. For example, adding printheads to the mounting support 501 does not weaken or destabilize the support. By using such a vertical mounting support instead of a flat plate of the prior art, the mounting support 501 can be sized to hold the required number of printheads with minimal bending. It should be understood that, according to one embodiment, one skilled in the art can mount the innovative printheads 503 and braces 502 on a flat surface, regardless of the bending of the support 501, allowing for some bending and correcting for such bending (which is not possible with the standard flat jet plate of Figure 2). This innovative configuration therefore improves the reliability and efficiency of mounting at least large printhead arrays by enabling the manufacture of compact, high-strength mounting supports, regardless of the number of printheads.

[0033] Figures 6A-6C are schematic diagrams of examples of different mounting schemes that can be used with the proposed method and apparatus. Element 601 is the print head, and element 604, similar to element 407 described above, is the original mounting point that remains unused in this embodiment. According to embodiments herein, brace 603 may have different shapes that allow the print head 601 to be mounted from different areas, such as from above the mount support 602, as shown in Figure 6A, from below the mount support 602, as shown in Figure 6C, or from the side of the mount support 602, as shown in Figure 6B. According to embodiments herein, the shape of brace 603 may be the same in each of Figures 6A-6C, but the print head placement can be different. Thus, this innovative brace 603 can have different mounting features (not shown) that allow the print head to be mounted from above (Figure 6A) or below (Figure 6B), for example. The brace can have a variety of shapes, but their purpose is the same: to provide a new mounting point that allows printer manufacturers to hold and secure the printhead on one side while leaving the other side of the printhead suspended or accessible. The shape of the mount support 602 can also vary, not limited to a flat plate or vertical bar, such as the T-beam 501 described in FIG. 5. The brace 603 can be attached to the mount support 602 in a variety of ways, such as with screws or adhesive. Common materials include, but are not limited to, stainless steel, aluminum, and carbon fiber. Less common materials include hard plastic.

[0034] The benefit of using braces to hold the S-shaped printhead on one side goes beyond increased flexibility in the design of the mount support. By leaving one side of the printhead free or suspended, that portion of the printhead is more accessible than the remaining portion. For example, this innovative configuration allows printhead assembly and maintenance to be performed much more easily than previously possible. For example, as shown in FIG. 5, by not using one side of the printhead to hold the printhead, operators are free to perform printhead maintenance. In contrast, a design similar to FIG. 2 would require not only some material 205-206 on both sides of the printhead 203, but also braces on the 205-206 beams to hold them in place. These braces further limit accessibility. Therefore, the innovations described herein improve accessibility to the printhead and its components.

[0035] Consistent with embodiments herein, new reference surfaces can be machined or mounted on braces (e.g., 405, 502, and 603) to modify and improve the method for mounting and locating a printhead on a printer. In an exemplary embodiment, the braces may be attached to the printhead by mechanical or optical alignment to align the new reference surfaces with the nozzles of the printhead. A jig may be used for such an operation. Such new reference surfaces can be seen in FIG. 4. In an exemplary embodiment, the original reference surface 402 is not used, and new reference surfaces 403 and 406 are machined directly into brace 405. In this example, the original reference surface 402 is flat, while the new reference surfaces are precision bores 403 and slots 406. This change in reference type allows the mounting of printhead 401 to be customized according to the needs of the printer manufacturer (e.g., Electronics For Imaging, Inc., Fremont, California). In one embodiment, in the absence of an optical jig, the original reference surface 402 may be used to align the brace 405 to the print head 401. Furthermore, some or all of the original reference surface 402 may be used when installing the print head into the printer. Alternatively, the reference surface may be completely replaced, as shown in the example of FIG. 4. Thus, according to embodiments herein, printer manufacturers can further customize the brace with auxiliary functions (e.g., providing a reference surface) in addition to the function of holding the print head on only one side.

[0036] conclusion The above description and drawings are illustrative and should not be construed as limiting. Numerous specific details are set forth to provide a thorough understanding of the disclosure. However, well-known details may not be described to avoid obscuring the description. Furthermore, various changes may be made without departing from the scope of the embodiments.

[0037] References herein to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. The appearances of the phrase "one embodiment" in various places herein do not necessarily all refer to the same embodiment, nor do they imply that different or alternative embodiments are mutually exclusive of other embodiments. Furthermore, various features may be described as being exhibited in some embodiments but not in other embodiments. Similarly, various features may be described as being a requirement of some embodiments but not in other embodiments.

[0038] The terms described herein generally have their ordinary meanings in the art, the context of this disclosure, and in the specific context in which each term is used. Certain terms used to describe this disclosure are described above or elsewhere herein to provide additional guidance to practitioners regarding the description of this disclosure. For convenience, certain terms may be highlighted, for example, using italics and / or quotation marks. The use of highlighting does not affect the scope and meaning of a term. The scope and meaning of a term are the same, in the same context, whether or not it is highlighted. It will be understood that the same thing can be expressed in multiple ways.

[0039] Accordingly, alternative language and synonyms may be used for one or more of the terms described herein, and no term has a special meaning, whether or not it is elaborated or discussed herein. Synonyms for certain terms are provided. The listing of one or more synonyms does not exclude the use of other synonyms. The use of any examples herein, including examples of terms described herein, is for illustrative purposes only and is not intended to further limit the scope and meaning of the disclosure or the scope of the exemplified term. Likewise, the disclosure is not limited to the various embodiments set forth herein.

[0040] Examples of devices, apparatus, methods, and their associated results according to embodiments of the present disclosure are described above without intending to further limit the scope of the disclosure. Titles or subtitles are used in the examples for the convenience of the reader, but in no way limit the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. In the event of a conflict, the present document, including definitions, will prevail.

[0041] From the foregoing, it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the scope of the invention. Accordingly, the invention is not limited except as by the appended claims.

Claims

1. 1. An apparatus for single-sided mounting of an S-shaped printhead to a mounting support of a printing press, comprising: abutting the S-shaped print head; and abutting against the mount support, This secures the S-shaped printhead for mounting at a single attachment point. The brace is constructed as follows: An apparatus comprising:

2. 2. The apparatus of claim 1, wherein the brace abuts the S-shaped print head by being attached to the S-shaped print head with optical or mechanical alignment, the alignment being directly aimed at the print nozzles of the S-shaped print head.

3. 10. The apparatus of claim 1, wherein the mount support is capable of stably holding an array of S-shaped printheads, the array comprising three or more S-shaped printheads.

4. 2. The apparatus of claim 1, wherein the brace abuts the S-shaped print head by being attached to the S-shaped print head using one or more attachment points on the S-shaped print head or using one or more attachment points on the brace.

5. 2. The apparatus of claim 1, wherein the brace is configured to mount the S-shaped print head to a face of the printing press in one or both of a horizontal and a vertical plane, thereby retaining the S-shaped print head to the printing press.

6. 10. The apparatus of claim 1, wherein the brace abuts the S-shaped print head by being attached to the S-shaped print head with any of or any combination of adhesive, one or more screws, one or more nails, one or more bolts, one or more removable clips, one or more loop and hook fasteners, adhesive, or other suitable fasteners.

7. 2. The apparatus of claim 1, wherein the brace abuts the S-shaped print head by being attached to the S-shaped print head with a single screw along with a mechanism to prevent rotation of the brace.

8. 10. The apparatus of claim 1, wherein the brace comprises one or more reference surfaces intended to control the positioning of the S-shaped print head by being precisely located relative to the print nozzles, thereby allowing a print manufacturer to effectively replace, in part or in whole, one or more original reference surfaces of the S-shaped print head.

9. the one or more reference surfaces are created and located on the brace using an optical or mechanical alignment process or are machined directly into the brace; the reference surface is located on the S-shaped printhead with a tolerance that exceeds the tolerance of one or more original reference surfaces; and the position is suitable for mounting the S-shaped print head to the mount support; 9. The apparatus of claim 8.

10. The apparatus of claim 1 , wherein the brace is attached to one side of the S-shaped print head so as to abut against the S-shaped print head.

11. The apparatus of claim 1 , wherein the brace abuts the S-shaped printhead by being mounted to a bottom of the mount support, a top surface of the mount support, or a side of the mount support.

12. The apparatus of claim 1 , wherein the brace is attachable to the mount support using one or more screws or adhesive.

13. The apparatus of claim 8 , wherein the one or more original reference surfaces are used to align the brace to the S-shaped printhead in the absence of an optical jig.

14. 1. A method for single-sided mounting of an S-shaped printhead to a mounting support of a printing press, comprising: attaching a brace to one side of the S-shaped print head; mounting the S-shaped printhead on one side of the S-shaped printhead to a mounting support of a printing press by attaching the brace to the mounting support; How to prepare.

15. The method of claim 14 , wherein the brace is attached to a bottom of the mount support, a top surface of the mount support, or a side of the mount support.

16. 15. The method of claim 14, wherein the brace is attached to the S-shaped printhead by optical or mechanical alignment, the alignment being directly to the print nozzles of the S-shaped printhead.

17. 15. The method of claim 14, wherein the brace is configured to mount the S-shaped print head to a face of the printing press in one or both of a horizontal and a vertical plane, thereby retaining the S-shaped print head to the printing press.

18. 15. The method of claim 14, wherein the brace comprises one or more reference surfaces intended to control the positioning of the S-shaped printhead by being precisely located relative to the print nozzles, thereby allowing a print manufacturer to effectively replace, in part or in whole, one or more original reference surfaces of the S-shaped printhead.

19. the one or more reference surfaces are created and located on the brace using an optical or mechanical alignment process or are machined directly into the brace; the reference surface is located on the S-shaped printhead with a tolerance that exceeds the tolerance of one or more original reference surfaces; 20. The method of claim 18, wherein the location is suitable for mounting the S-shaped printhead to the mounting support.

20. 20. The method of claim 18, wherein the one or more original reference surfaces are used to align the brace to the S-shaped printhead in the absence of an optical jig.

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