Patent Application
20170217157
Flexographic printing refers to a machine printing process involving the use of cylinders or rollers to impart a print design onto a print medium. The print medium can be any type of substrate capable of receiving printing ink such as paper, cardboard, plastic, metal film, and packaging material, to name a few examples. The print design can include any desired text and/or graphics, and is provided in relief onto a so-called printing plate. The printing plate is a flexible rubberlike sheet that is attached to a print cylinder of the flexographic print machine. The print plate itself can be made using a mold, or by using a chemical or laser etch process. In a typical mold-based plate forming process, a mold such as a bakelite board is formed with the desired design, and a plastic or rubber compound is then pressed into the mold under pressure and temperature to produce a flexible printing plate. In a chemical-based plate forming process, a mask or film negative embodying the desired print design is placed over a light-sensitive photopolymer plate blank. The masked plate is then exposed to ultra-violet light, such that the photopolymer hardens where light passes through the mask. The remaining unhardened photopolymer is then washed away with an appropriate solvent. In a typical laser-based plate forming process, an image of the desired print design is scanned, computer-generated, or otherwise digitized. A computer-guided laser then etches that image onto a printing plate. Given the attendant print quality and cost effectiveness, photopolymer plates are most commonly used. In any such cases, a printing plate is attached to a given print cylinder using a double-sided adhesive. Some such adhesives include an intervening foam layer, to provide varying degrees of softness. In operation, the raised portions of the resulting printing plate carry ink to the print medium. There are a number of non-trivial challenges involved in attaching a printing plate to a print cylinder.
Note that the figures are not necessarily drawn to scale. Moreover, the figures are drawn to depict certain features and do not necessarily reflect actual geometries involved. For instance, some of the figures may refer to or otherwise be discussed with reference to cylinders, yet the figures are drawn with relatively flat lines, so as to simplify drafting. Numerous permutations and mixes of the various techniques and features provided herein will be apparent in light of this disclosure.
Techniques are disclosed for connecting a printing plate to a print cylinder or sleeve using a mechanical bond. The techniques may be implemented, for instance, with respect to a printing plate, a print cylinder, a print sleeve, or a system including any combination thereof. In an embodiment, a field of mechanical fasteners is provisioned on a printing plate, and a complementary field of mechanical fasteners is provisioned on a print sleeve or print cylinder. The mechanical fasteners collectively operate to provide a mechanical bond or interface that not only inhibits lateral and rotational movement of the plate during printing operations, but can also be configured to manage backlash between engaging surfaces of the interface. In some cases, backlash management includes the use of unidirectional fastening elements (such as unidirectional angled hooks) and/or an engineered cushion effect integral with the mechanical bond itself. The mechanical bond may be implemented, for example, with hook-and-loop, hook-and-hook, hook-to-channel, male/female-type fittings, vacuum, suction, magnetics, interlocking gears, or any combination thereof. The connection system may be further configured to inhibit edge and seam lifting of the plate, and may be implemented in a modular fashion so as to allow for a partial plate change-over. The techniques may be equally applied to any number of other plate-based printing systems, whether cylindrical in nature or otherwise (e.g., flat bed printing presses).
General Overview
As previously explained, there are a number of non-trivial challenges involved in attaching a printing plate to a print cylinder. In more detail, a given plate is normally mounted to the print cylinder using a double-sided adhesive tape. The tape may or may not have an intervening foam layer. During the mounting process, the tape is first applied to the print cylinder. This must be accomplished without trapping any air bubbles between the tape and cylinder. The back-side liner of the double-sided tape is then removed and the plate is carefully attached thereto. The plate must be correctly positioned onto the tape and methodically applied to the cylinder in a rolling fashion, again making sure to avoid any air bubbles between the plate and tape. This is generally a time consuming process. Also, depending on the strength of the tape adhesive, the attached plate can be difficult to remove from the print cylinder and is not reusable if the plate is damaged (e.g., stretched or torn) during removal. Moreover, the tape adhesive tends to leave a residue on the plate and cylinder, which has to be removed prior to attaching a new plate thereby further increasing change-over time. In addition, if the plate is not attached properly due to positioning error or the presence of air bubbles, the resulting print quality may be inadequate (e.g., inconsistent application of ink, unacceptable dot gain, misaligned print features, and failure to adequately print certain features). Furthermore, plates attached using double-sided tape can sometimes exhibit edge peeling along the lateral edges of the print plate and/or along the seam where the ends of the print plate meet, further causing print quality issues, particularly with respect to longer print runs.
Thus, and in accordance with an embodiment of the present disclosure, techniques are disclosed herein for connecting a flexographic printing plate to a print cylinder using mechanical fasteners. The mechanical fasteners operate to provide a mechanical bond or interface that not only inhibits lateral and rotational movement of the plate during printing operations, but can also be configured to manage orthogonal play or so-called backlash between engaging surfaces of the interface. As will be appreciated in light of this disclosure, the techniques may be implemented with respect to a printing plate, a print cylinder, a print sleeve, or a system including a plate-sleeve, a plate-cylinder, or a plate-sleeve-cylinder combination, in accordance with various example embodiments. The mechanical bond may be implemented, for instance, with one or more of the following: hook-and-loop, hook-and-hook, hook-to-channel, male/female-type fittings, vacuum, suction, and magnetics. To this end, the mechanical faster elements can include hook elements, loop elements, channel elements, ridge/groove elements, pin/hole elements, interlocking gear elements, vacuum channels/holes, suction elements, magnets, or any combination thereof. Numerous embodiments and variations thereof will be apparent in light of this disclosure, including both flexographic printing systems and other plate-based printing systems.
In an embodiment, one or more fields of mechanical fasteners are provisioned on a printing plate, and one or more complementary fields of mechanical fasteners are provisioned on a print sleeve or the print cylinder itself (or an adaptor thereof, or so-called carrier sleeve). In some such cases, backlash management includes the use of an engineered cushion effect integral with the mechanical bond itself to reduce backlash, and further to eliminate or otherwise reduce the need for a separate foam layer external to the mechanical bond. In other embodiments, backlash management includes the use of unidirectional and possibly angled fastening elements (such as a field of unidirectional angled hooks) that operate to create a snugging effect during printing operations, thereby reducing backlash. Other configurations may include a mechanical bond having a relatively consistent degree of backlash that operates in conjunction with a separate external foam layer. Still other configurations may include a mechanical bond configured with little or no backlash that can be used with or without a separate external foam layer. Thus, numerous degrees of interface hardness/softness can be provided to support a full range of printing applications. In any such cases, the overall thickness profile of the interface, including any functional layers external to the interfaced surfaces, changes predictably throughout a given printing process, and quickly transitions from a first (compressed) thickness when compressed between print rollers to a second (uncompressed) thickness when not compressed between print rollers. In some such embodiments, note that the compressed thickness and the uncompressed thickness may be substantially the same, depending on the hardness of the interface. The hardness of the interface can be selected based on features of the print design.
In some embodiments, the mechanical fasteners attendant to the mechanical bond are integral with the corresponding printing element, thereby eliminating the need to make an adhesive-based connection between the mechanical fastener medium and the printing element at change-over time. For instance, in one embodiment, a shrink-wrap print cylinder sleeve is configured with mechanical fasteners such as hook and/or loop formed on the outside surface of the sleeve (e.g., using a mold or laminating process, or other suitable forming process). A printer operator can slide such a sleeve onto a given print cylinder (or an adaptor thereon) and shrink the sleeve onto that cylinder with the application of heat. Once the sleeve is securely shrunk onto the print cylinder, its outward facing mechanical fasteners can form a mechanical bond with corresponding mechanical fasteners of the various print plates that may be subsequently installed. In another embodiment, a print cylinder is configured with mechanical fasteners formed on the outer physical layer of the print cylinder itself. For instance, the print cylinder may have a metal or otherwise rigid core with an outer layer of polyurethane or other suitable material that has mechanical fasteners such as hook, loop, channels, ridges, gear elements, and/or vacuum channels formed thereon. In such cases, a print plate having complementary fasteners on its non-print side can be mechanically bonded to the print cylinder. Similar embodiments apply to situations where the print cylinder is modified by a so-called carrier sleeve. As is known, a carrier sleeve can be designed to provide a relatively tight tolerance and can be used as an adaptor to increase print cylinder diameter but at a lower weight/inertia as compared to simply using larger steel cylinders. Thus, a carrier sleeve may be configured with mechanical fasteners just as a print cylinder may. To this end, for purposes of this disclosure, assume that any adaptor or so-called carrier sleeve that can be provided between the print plate and the print cylinder is included in the term print cylinder. In yet another embodiment, a print plate blank can be formed on a one side of a substrate that has mechanical fasteners formed on its other side. In one such example case, the print plate blank can subsequently be processed to have a print design formed on the print side of the plate by using, for instance, a chemical etch process assuming a photopolymer plate blank.
Note that a plate blank configured as provided herein can be selected for a given print design, based on the mechanical fastener arrangement on the non-print side and the cushion effect associated therewith when bonded with a particular mechanical fastener arrangement on the print sleeve/cylinder. For instance, Table 1 allows an operator to select a given plate blank based on the particulars of a given print design. Assume the mechanical fastener arrangement on the print sleeve/cylinder is known. As can be seen in this example print scenario, a hard cushion effect can be used when the print design is substantially dominated with bold/solid design features (lacking in fine details), and a soft cushion effect can be used when the print design is substantially dominated with a mixture of points (exhibiting fine details). A medium cushion effect may be used when both bold/solid and point mixture design features appear in the print design.
As will be appreciated in light of this disclosure, such integral mechanical fasteners on the print plate and/or print sleeve or cylinder can greatly simplify the print plate installation process. In one example case, for instance, while the plate may be configured with one or more fields of mechanical fasteners, the print cylinder can be configured with complementary field(s) of mechanical fasteners that can remain on the print cylinder for use with other print plates. So, depending on the particulars of the desired print design, a print plate can be selected that has a mechanical fastener arrangement which will operate in conjunction with the mechanical fasteners on the print cylinder to provide the appropriate cushion effect suitable for that design. For instance, a print design having a multi-color skin tone type image with relatively small features may be better suited for printing with a softer cushion effect, while a print design having one solid color image with relatively large features may be better suited for printing with a harder or minimal cushion effect. Thus, the appropriate print plate blank mechanical fastener arrangement may be one of the only variables requiring consideration at set-up time, which means fewer choices and lower complexity for the printing press operator. Such simplified set-up would be advantageous.
Further note that the mechanical bond may also be configured to effectively self-align during plate installation or otherwise facilitate proper positioning of the plate onto the print sleeve/cylinder, so the operator can quickly and easily conduct a change-over from one print plate to the next. To this end, the interface may include any number of self-aligning features such as pin/hole, ridge/channel, hook/hook, hook/channel, male/female-type elements, and other such arrangements that effectively provide the operator a visual queue or place-holder as to where to place the plate on the print cylinder as well as provide at least an initial holding force while the plate is subsequently wrapped and secured onto the print cylinder. Note that the alignment feature(s) may be part of the mechanical bond and actually provide holding power or may just provide alignment. To this end, the alignment feature(s) may be independent of the mechanical fasteners.
As previously indicated, the mechanical bond can be implemented using any number of mechanical fasteners, including hook elements, loop elements, channel elements, ridge elements, male/female-type elements (e.g., pin/hole elements, ridge/groove elements, press-fittings, interlocking gear elements, other grab elements), vacuum channels/holes, suction elements, magnets, or any combination thereof. In one specific example embodiment, a printing plate includes a field of unidirectional angled hooks facing in a first direction, wherein the hooks engage with loop material of the print sleeve or cylinder. Alternatively, the printing plate may include field(s) of loop designed to engage a field of unidirectional angled hooks provided on the print sleeve/cylinder. In either case, the angle and geometry of the hooks operate in conjunction with the loop material and rotation direction of the print cylinder to provide a snugging effect that inhibits backlash of the mechanical bond. In one specific such case, a second field of unidirectional hooks facing in a direction opposite to the first direction is provided proximate the seam where the ends of the plate meet. Again, the hooks may be provisioned on the plate or the sleeve/cylinder. In another specific example case, the loop is configured with a two-level loop field wherein the shorter loops of the first (lower) level engage the unidirectional hooks and the taller loops of the second (upper) level provide a degree of compressibility or engineered cushion effect once the hooks are engaged with the lower level loops. In another specific example case, a field of loop effectively having one loop level is encased in a foam material. In some such cases, the tips of the loops extend from the top of the foam when the foam is in its uncompressed state, while in other cases the tips of the loops extend from the top of the foam only when the foam is in a compressed state. In either such cases, the bottom of the hooks press into the foam when the hooks engage with the loops, thereby providing a cushion effect that limits backlash. In some cases, the hooks are angled, so as to provide a snugging effect as well, during print operations. In other such example embodiments, the hooks are not angled. In still other such example embodiments, the hooks are not angled or unidirectional. In still other such example embodiments, the hooks are encased in a foam material (partially or completely), rather than the loop.
In another specific example embodiment, a printing plate includes a first field of hooks and the print sleeve or cylinder includes a second field of hooks complementary to the first hook field. The resulting hook-and-hook mechanical bond can be configured with little or no backlash or cushion effect to provide a relatively hard interface, or with an engineered cushion effect integral to the mechanical bond to provide a softer interface. In the latter case, for instance, hooks of one field can be at least partially encased in foam that compresses when the opposing hooks engage as previously explained with respect to a loop field so as to provide a degree of compressibility and a relatively softer interface.
Numerous variations and permutations will be apparent in light of this disclosure, and any number of mechanical fastener types may be used to form a mechanical bond having such an integral cushion effect as provided herein. For instance, magnetic elements may be embedded within a plate body having a foam layer through which the magnetic forces engage a metal print cylinder or sleeve to provide an engineered cushion effect. In another embodiment, vacuum elements may be embedded within a plate body having a foam layer through which the vacuum forces engage a print cylinder or sleeve to provide an engineered cushion effect. Alternatively, the magnet or vacuum elements can be applied directly to the print cylinder or sleeve to provide a relatively harder interface. Still other embodiments may include a combination of vacuum and magnetics. In one such case, the magnetic bond is weaker than the vacuum bond, and allows an operator to readily mount the plate onto a print cylinder and to align accordingly. Once aligned, the vacuum can be engaged. In another embodiment, suction elements may be provisioned on the non-print side of a plate, so that the suction cups engage a print cylinder or sleeve. In any such embodiments, an external layer of foam may also be used to provide a further degree of compressibility, depending on particulars of the print job.
As will be further appreciated in light of this disclosure, the various printing elements may be configured to inhibit edge and seam lifting of the plate. In some embodiments, for example, the density of mechanical fasteners proximate the plate edges/seams can be increased to provide greater holding power in those areas, whereas a lower density of mechanical fasteners can be provided in the central plate area. In other embodiments, a first type of mechanical fastener can be used near the plate edges/seams and a second type of mechanical fasteners can be used to secure other locations of the plate. For example, in one such case, magnets and/or vacuum channels are provisioned along the plate edges/seams while other central parts of the mechanical bond can be provided, for instance, by a hook-hook or hook-loop interface. In another example such case, male-ridges or female-channels can be provisioned along the plate edges/seams while other central parts of the mechanical bond can be provided, for instance, by a magnetic, suction, or vacuum interface. In still other example embodiments, a conventional double-sided adhesive tape (with or without foam) can be used to secure the central portion of the plate, and only the plate edges/seams are configured with mechanical bonding elements. In any such cases, the complementary portion of the mechanical bond can be provided on the print sleeve/cylinder thereby allowing for enhanced or otherwise robust holding power at the plate edges/seams.
As will be further appreciated in light of this disclosure, a given plate may be provided in a modular form, so as to allow for a partial change-over. For example, a portion of a print plate design that is known to wear out quicker than other parts of that design can be modularized or otherwise isolated so that it can be attached and removed as an individual piece, using the same mechanical bonding techniques as provided herein including any enhanced seam/edge bonding. So, a given plate portion can be swapped out from any location on the print sleeve/cylinder, whether it be in a central location of the plate and surrounded by other plate portions, or an edge location. To this end, note that such a modular print plate can be assembled much like a puzzle that includes two or more pieces. For instance, a two piece plate might include two halves or a frame portion and a central portion, while a six piece plate might include four frame portions and two central portions. Any number of plate break-down schemes can be used. Note that such a modular plate scheme allows for self-alignment during partial change-over, given the puzzle-piece nature where one piece can be positioned into place between or otherwise next to already placed pieces. Such self-alignment further facilitates quick change-over times.
Thus, the techniques can be used to provide a stable connection across the complete surface of the print plate, including along the print plate edges and at the seam where the print plate ends meet. Because there is minimal or no use of adhesive to form the mechanical bond, the techniques may further allow for easier re-use of plates as well as easier and quicker changeovers. To this end, further note that there is no need to remove any adhesive residue from the print cylinder or plate, in some embodiments. In addition, while the plate may be configured with one or more fields of mechanical fasteners, the print cylinder can be configured with complementary field(s) of mechanical fasteners that can remain on the print cylinder for use with another print plate (or the same print plate, as the case may be). So, in one particular such embodiment, a desired print design can be initially assessed in advance of transferring that design to a print plate blank so as to determine the best plate blank to use, giving consideration to the cushion effect that will result from the particular mechanical fastener(s) provisioned with that print plate blank and the given print sleeve/cylinder.
Note that, as used herein, the term ‘inhibit’ is not intended to necessarily mean prevent or absolutely eliminate. Rather, inhibit as used herein generally refers to the ability to minimize or otherwise reduce the ability to do something. For instance, in embodiments where the closure system inhibits edge lifting, the occurrence of edge lifting is either eliminated or otherwise reduced relative to other closures not configured as provided herein. Likewise, in embodiments where the closure system inhibits backlash of the mechanical bond, the occurrence of backlash is either eliminated or otherwise reduced relative to other closures not configured as provided herein. Likewise, in embodiments where the closure system inhibits lateral and rotational movement of the plate during printing, the occurrence of lateral and rotational movement is either eliminated or otherwise reduced relative to other closures not configured as provided herein.
Further note the term ‘manage’ and its derivatives as used herein with respect to managing backlash generally refers to the intentional changing or manipulation of naturally occurring backlash associated with a mechanical bond. To this end, a managed backlash of a given mechanical bond is different and distinct from the naturally occurring backlash associated with that bond. The difference may be, for example, with respect to a reduction in backlash distance at any given engagement point in the mechanical bond, or at multiple engagement points in the bond, or at all engagement points of the mechanical bond. In some embodiments, at least 50% of the engagement points of the mechanical bond are associated with reduced backlash distance, in accordance with an embodiment. In other embodiments, at least 75% of the engagement points of the mechanical bond are associated with reduced backlash distance, in accordance with an embodiment. In still other embodiments, at least 95% of the engagement points of the mechanical bond are associated with reduced backlash distance, in accordance with an embodiment. In one specific embodiment, 100% of the engagement points of the mechanical bond are associated with reduced backlash distance. As will be appreciated in light of this disclosure, an engagement point is a mechanical fastener element engaging with a complementary fastener element. For example, an engagement point is a hook engaging with one or more loops or perforations, such that the hook needs to be forcibly pulled/peeled to separate from the one or more loops or perforations.
Example Print Systems and Print System Elements
Numerous other flexographic and non-flexographic print system configurations can be used, and the present disclosure is not intended to be limited to any particular one. For instance, the print plate 109 may be connected directly to the print cylinder 107, or indirectly via a print sleeve that is shrunk onto or otherwise connected to the print cylinder 107. To this end, various such print system elements may be used to form the mechanical bond. Also, other embodiments may not include the impression cylinder 111, or may include a different roller orientation (e.g., vertical as opposed to horizontal). Likewise, other embodiments may include additional components or stations, such as a dryer for setting or otherwise drying the applied ink(s), or in the case of UV-cured inks, a UV curing station. In a more general sense and as will be appreciated in light of this disclosure, the print plate mounting techniques provided herein can effectively be used on any print system having a print plate fastened to a print cylinder or other print machine surface. As will be further appreciated, the plate mounting techniques can be used with other printing systems as well, such as those having a non-cylindrical printing surface, such as a flat-bed printer that works in conjunction with changeable printing plates. Any number of plate-based printing systems may similarly benefit, such as offset, gravure letterpress, screen, and other such plate-based printing systems.
In some embodiments, the mechanical fastener 203 is integrally formed with the body of the plate 209a through an extrusion and/or laminating process, or a three-dimensional (3D) printing process. In one specific example such embodiment, the plate 209a is a co-extrusion of photopolymer (to provide the printing surface of side 201) and thermoplastic (to provide the mechanical fastener 203). The thermoplastic can be, for example, polyethylene, polypropylene, nylon, or polyester, to name a few examples. A 3D print process also can be used to form such a structure. Various backing films or intervening material layers can be used to increase interlayer bonding strength, if affinity between photopolymer and mechanical fastener materials is insufficient. In another specific example embodiment, the plate 209a is an extrusion or mold of photopolymer or some other suitable material to provide both the printing surface of side 201 and the mechanical fastener 203. In one such case, the plate 209a can be formed with mechanical fastener elements embedded or formed in the non-print side surface of the print plate, such as embedded magnets or metal flakes or pieces suitable for use in a magnetic bond and/or surface-formed vacuum channels suitable for use in a vacuum bond, and/or embedded and protruding hooks and/or loop suitable for use in a hook/loop bond. In other such integrally formed embodiments, hook tape or loop tape or a combination of hook-and-loop tape can be used to provide a substrate upon which a print plate is coated or otherwise formed. In non-integrally formed embodiments, the mechanical fasteners can be applied to non-print side of a pre-existing print plate by, for example, a double-sided tape or other suitable bonding technique (e.g., adhesive, thermal or ultrasonic weld).
Example embodiments having a combination of elements making up mechanical fastener 203 include, for instance, a print plate 209a having both vacuum and magnetic elements, wherein the magnetic force is lighter than the vacuum force so as to allow for initial positioning of the plate on a given print cylinder or print sleeve using the magnetic force, and the stronger vacuum force can be engaged to lock the plate in position once registered on cylinder. In another example combinational embodiment, elements that can be used to assist not only in securing the plate to print cylinder/sleeve but also in plate alignment and positioning can be provisioned at the edges (along all four edges or some subset thereof) of plate 209a. For instance, hook, channel, ridge, groove, and/or other male/female grab-type elements can be used in the two leading corners or along the leading edge of the plate 209a, and vacuum, magnetic, hook, and/or loop elements can be provisioned everywhere else. Such alignment features help a printing press operator position and/or initially secure the plate 209a to a given print cylinder or print sleeve so as to avoid registration errors, particularly when those guides are formed in a common process that produces both the alignment features and the print pattern features. Further, note that not every portion of the plate 209a needs to be bonded. To this end, the mechanical fastener 203 may be a pattern of fasteners or otherwise selectively provisioned on the non-print side of the plate 209a, so long as the areas lacking any mechanical fastener don't cause undesired printing issues. The density of mechanical fastener element clusters can be adjusted to meet this goal, as will be appreciated.
In some example cases, print plate 209a is a blank plate that has no print design on it; rather, the design can be added at a later time using standard photopolymer chemical etch processing, once the blank plate with mechanical fastener 203 is formed. In other example cases, print plate 209a can be formed as a ‘ready-to-print’ plate that has a desired print design formed on print side 201 as part of the plate forming process. This could be accomplished, for instance, using 3D printing process coupled with a UV curing stage to set the printed design on the print side 201 (assuming a UV cured photopolymer is dispensed by the 3D printer to form the print side 201). Note that by forming the mechanical fastener 203 (including any alignment features) in effectively the same process as the print features of side 201 are formed creates a self-aligning aspect to print plate 209a that may help alleviate the potential for registration errors associated with processes that form the print design in a subsequent distinct process after the plate has been formed.
In any such cases, the mechanical fastener 203 may operate in conjunction with a corresponding mechanical fastener of the print cylinder or sleeve to provide a degree of orthogonal play including backlash once the mechanical bond is formed when the plate 209a is mounted. The degree of backlash may be small in some cases (such as in the case of hook-and-hook and hook-to-channel mechanical bonds) or relatively large in other cases (such as in the case of certain hook-and-loop mechanical bonds). As will be appreciated in light of this disclosure, left unmanaged or otherwise unacknowledged, such backlash may cause print quality problems, depending on the degree of backlash and the particulars of the given print pattern design.
In some embodiments, the print cylinder 207a is a conventional print cylinder, and mechanical fastener 211 is attached to the outer surface of cylinder 207a as an add-on component. In one such example case, mechanical fastener 211 is implemented with tape having adhesive on one side and mechanical fastener elements formed on the other side. Again, the mechanical fastener elements on the tape can vary, and may include, for example, hook, loop, vacuum, suction, magnet, gear, channel, or ridge elements or some combination thereof. In any case, the adhesive tape can be wound around cylinder 207a to cover a substantial portion of the outer surface (e.g., 50% or more). In some such cases, the tape is spiral wound, which may help further inhibit edge lifting.
In other embodiments, the print cylinder 207a is configured with an integral mechanical fastener 211. In one such example case, mechanical fastener 211 is implemented with a plastic or polyurethane layer having mechanical fastener elements formed on its perimeter (via molding, machining, extrusion, 3D printing, or other suitable forming method). The integral fastener layer 211 can be formed, for example, over a print cylinder core or adaptor, having a desired diameter and roundness. Again, the mechanical fastener elements on fastener layer 211 can vary, and may include, for example, hook, loop, vacuum, suction, magnet, gear, channel, or ridge elements or some combination thereof.
In some embodiments, the print sleeve 215a is a conventional print sleeve, and mechanical fastener 217 is attached to the outer surface of sleeve 215a as an add-on component. In one such example case, mechanical fastener 217 is implemented with tape having adhesive on one side and mechanical fastener elements formed on the other side. Again, the mechanical fastener elements on the tape can vary, and may include, for example, hook, loop, vacuum, suction, magnet, channel, gear, or ridge elements or some combination thereof. In any case, the adhesive tape can be wound around sleeve 215a to cover a substantial portion of the outer surface (e.g., 50% or more). In some such cases, the tape is spiral wound, which may help further inhibit edge lifting.
In other embodiments, the print sleeve 215a is configured with an integral mechanical fastener 217. In one such example case, mechanical fastener 217 is implemented with a plastic or polyurethane layer having mechanical fastener elements formed on its perimeter (via molding, machining, extrusion, 3D printing, or other suitable forming method). The integral fastener layer 217 can be formed, for example, over a print sleeve core, having a desired diameter and roundness. Again, the mechanical fastener elements of mechanical fastener 217 can vary, and may include, for example, hook, loop, vacuum, gear, suction, magnet, channel, or ridge elements or some combination thereof.
In still other embodiments, the print sleeve 215ais configured as a heat-shrinkable sleeve having an integral mechanical fastener 217. In one such example case, the print sleeve 215a is implemented with a tube of nylon or polyolefin having mechanical fastener elements formed on its perimeter (via molding, machining, extrusion, 3D printing, or other suitable forming method). Again, the mechanical fastener elements of mechanical fastener 217 can vary, and may include, for example, hook, loop, vacuum, gear, suction, magnet, channel, or ridge elements or some combination thereof.
In any of the various embodiments disclosed herein, note that it may be useful to employ a slip sheet during the plate mounting process. For example, in some embodiments, a slip sheet may be positioned between the mechanical fastener of the print cylinder/sleeve and the mechanical fastener of the print plate. In general, the slip sheet comprises a material that does not engage with the mechanical fasteners and allows for alignment and adjustment of the print plate on the print cylinder/sleeve prior to engagement of the opposing mechanical fasteners. Once alignment is complete, the slip sheet may be removed thereby allowing the mechanical fasteners to engage and lock the print plate to that selected position. This may be completed in an incremental rotational process that will prevent plate shifting as well as air pockets or wrinkling between the bonding surfaces. In some embodiments, the slip sheet is perforated or otherwise segmented into a number of sub-sheets so as to facilitate its incremental or piecewise removal during the mounting process. In one example case, the slip sheet is segmented into strips that run lengthwise across the print cylinder. The strips can be, for instance, one to three inches wide and delineated with perforation lines. Examples of slip sheet materials may include plastic films, paper, foils or other suitable materials that will prevent engagement of the opposing mechanical fasteners but that can also be slipped out from between those opposing mechanical fasteners.
Example Hook-and-Loop Mechanical Bonds
As can be further seen, there is a degree of orthogonal play associated with the mechanical bond. In particular, d1 represents the potential backlash distance of the hook-loop connections making up the bond, if not in a snugged state during print operations.
As can be seen with the example embodiment in
For instance, and as can be seen with the example embodiment in
In some example cases, the hook elements are configured to penetrate up to the base of the loop field, or even penetrate through that base and up to the print plate or sleeve (d3 is zero). In some such embodiments, the corresponding loop field is configured with loop spacing sufficient to allow for relatively easy hook penetration.
As will be further appreciated in light of this disclosure, such a hook field can be used on a print plate, print sleeve, or print cylinder, and the corresponding loop field(s) can be provided on the other element to form the mechanical bond. Table 2 summarizes the relationship between the location of the unidirectional hook field with respect to the hook direction and machine direction.
Note that the hook direction does not have to be precisely aligned with the machine direction, so as to be exactly the same direction. Rather, there may be some degree of offset between the two directions. For instance, in one example case, the hooks may be facing in a direction that is up to 30 degrees different from the machine direction. This might be the case, for instance, when unidirectional hook tape is applied to the print cylinder in a spiral wound fashion, or the hooks are otherwise formed on the cylinder in an offset fashion. In a more general case, the unidirectional hooks can be facing in any direction that is within +/−90 degrees of the actual machine direction. Said differently, the angle formed by a first vector representing the hook direction and a second vector representing the machine direction is not greater than a right angle, in accordance with some embodiments.
Such a hook field 363 can be made using, for example, extrusion or mold techniques to provide a hook tape that can then be applied to the desired print element (e.g., print plate, cylinder, sleeve). In other embodiments, the hook field 363 can be co-extruded or otherwise integrally formed with a photopolymer or other suitable plate material. In other such integrally formed embodiments, the hook field 363 can be used as a substrate upon which a plate is then formed. In still other such integrally formed embodiments, the hook field 363 can be formed in a layer of polyurethane, resin, or other suitable material on a print cylinder core or outer cylinder portion, such that at least part of the print cylinder and the hook field 363 are of a unitary mass of common material. Such a cylinder could be formed, for example, using a molding process that injects the desired material into an appropriate cylinder mold having the desired circumference and hook pattern (and/or other fastener elements) represented therein. In still other embodiments, the hook field 363 can be co-extruded or otherwise integrally formed with a heat-shrinkable material to provide a shrink sleeve. In still other embodiments, the hook field 363 can be co-extruded or otherwise integrally formed with a stretchable material to provide an elastic sleeve.
In one example case, hook field 367 is implemented with spiral wound hook tape, wherein the hook tape is configured with a field of unidirectional hooks. Such a combination of unidirectional hooks and spiral winding tends to inhibit edge lifting. In still other such embodiments, the unidirectional hooks are angled downward (rather than standing straight up) so as to provide an acute angle with the surface of cylinder/sleeve 307. In one such case, the unidirectional angled hooks 367 cause a plate snugging effect when the cylinder 307 rotates in the machine direction. In particular, a given loop of field 365 catches on an angled hook of field 367 and is effectively forced toward the vertex of the acute angle (closer to the surface of the cylinder). Not wishing to be limited to any particular theory, it seems that such forces resulting from the machine rotation and unidirectional hook scheme eliminate or otherwise reduce backlash normally attendant a hook-loop bond.
As can be further seen in
In more detail, and as shown in
Textile fabrics are generally made using a weaving, circular knitting, warp knitting, flat-bed knitting, and non-woven processes, and any of these processes can be used to create a hook engageable fabric in accordance with an embodiment of the present disclosure. Many textile fabrics do not contain a pile surface and are used for general textile use. Other textile fabrics which are often manufactured for fleece fabrics are manufactured with a pile surface and the pile surface is napped and broken. This napping process can create an irregular pile height. In many cases this fabric is then sheared to create a uniform pile height such as used in velour and Polartec® fabrics but because the loop pile has been broken or sheared, these fabrics are not hook engageable. To this end, unbroken loop fabrics are required if they are to be used as hook fasteners. These fabrics are often napped fabrics, and subject to pile height irregularity mentioned above. While napped or irregular pile height fabrics may work in some cases, there are a number of ways to make the thickness of fabric relatively consistent for purposes of backlash management, in accordance with an embodiment of the present disclosure. For example, a warp knit fabric made on a 3-bar knitter where a 3rd dimensional loop pile is formed on the knit machine will generally have a consistent thickness if a napping or brushing step is not performed. Additionally, a 2-bar warp knit machine with a pile device, where a 3-dimensional pile is formed on the machine, can also make an unnapped warp knit fabric having a consistent thickness. In more detail, with many 2-bar fabrics commonly made, the third dimension pile is formed by napping or brushing to raise the pile. The napping process disorients the pile surface, and often can create a loop pile height with varying thickness.
In another example embodiment, a warp or circular knit fabric using multifilament texturized yarns can be used to implement the loop field of the mounting system. For instance, in some example cases, yarns can be used to create a pile by using flat yarns that can be monofilament or multifilament. Multifilament yarns can be flat yarns with round or other cross-sections, where the fibers in the yarn are straight.
In another example embodiment, so-called spacer fabrics can be made by weaving, or by using circular or warp or flatbed knitting machines. As is generally known, these types of conventional fabrics include top and bottom fabric layers, with a mono or multifilament yarn connecting the top and bottom layers. In accordance with an embodiment herein, a spacer fabric integral to the loop layer can be used to provide a cushioning effect beneficial to the print process. In one such embodiment, with additional knitting bars added, the spacer fabric knitting machine can also knit a loop pile on one or both of the top and bottom spacer fabric surfaces. This type of modified spacer fabric may be preferred in plate mounting applications tolerant of thicker closures.
In another embodiment, yarn size (denier) and yarn thickness changes can be made to change fabric thickness of warp or circular, or flatbed knit fabrics. For instance, in plate mounting applications where a thin closure is preferred, the overall textile loop thickness can be changed by changing yarn denier, and by also utilizing flat or textured yarns. When these yarns are placed in the fabric ground or backing (loop base), the backing thickness changes. In one example plate mounting closure system configured in accordance with an embodiment of this disclosure, the loop pile may allow entry by its mating hook, so that the overall thickness of the closure is mostly determined by the thickness of the ground or back of the textile, and the thickness of the hook. The thickness of the back of the loop textile can be changed by changing the yarn denier. In some cases, fine yarns with a low thickness as low as 10 denier, can be used to make a very thin backing. Thicker yarns such as 20, 40, 70, 100, 140 denier yarns can be used in light to medium weight circular or warp knit fabrics. Heavier yarns around 250 denier are used in heavier weight knit, but yarns exceeding 1000 denier are available.
In another embodiment, selectively punctured or perforated loop fabric can be used. In more detail, one example case of a hook-and-loop plate mounting closure system can be configured so that a least some hooks penetrate past the loop component (if present) and through the ground (loop base), and anchor into the backside of the loop fabric when compression applied during the mounting process is released. In one specific such case, a dual-height hook arrangement is provided, wherein the loop fabric is designed to intentionally create waffle like openings into the loop fabric backing thereby allowing taller hooks to penetrate through these openings, while shorter hooks engage with the loops. In one such case, the taller hooks can be configured to better pass through the loop base material (e.g., J-hook, arrow-head hook, one-way hook), while the shorter hooks can be configured abut up against the loop base (e.g., palm-tree or mushroom or nail-head hook). In some cases, a plain fabric could be punctured to create openings for hooks to enter. In some such cases, a bed of spaced needles used to puncture the fabric can be heated, to melt and seal the puncture edges to prevent fraying. Using this type of compressed plate mounting closure system can be used to reduce the overall thickness of the closure system.
In another embodiment, a two-level loop fabric can be used. In more detail, a warp or circular knit fabric is configured with two distinct height levels of the loop pile. The upper loop pile can act as a spring or integral cushion, so when the closure is compressed, the hook would engage with the lower level loop. As with other integral cushioning techniques provided herein, backlash can be reduced or otherwise managed to create a tighter and more consistent plate mounting system closure. In some cases, the higher loop could be made using flat yarns of high-tenacity which would be stiffer, and provide a spring-like rebound after engaging. In other cases, high-bulk texturized yarn could be used as the upper layer, which would accomplish a similar function. Switching the location of flat and texturized yarns in the two-level fabric construction may provide improved performance, for some printing applications.
In some cases any of the yarns mentioned with respect to
In another embodiment, stretch latex coatings can be used in the plate mounting closure system. For instance, on some stretch fabrics, a latex or rubberized coating can be applied to the loop fabric backing to provide additional reinforcement to stretch fabrics. These coatings can also be used to provide some cushioning and rebound from compression (integral cushion effect).
As will be further appreciated in light of this disclosure, the thickness (height) of the loop can be optimized to work with particular hook geometry to provide a relatively thin closure. So, in accordance with one embodiment, a dense hook field having a relatively low-profile (e.g., 1700 hooks per square inch, with each hook 0.02 inches in height) can be used in conjunction with an unnapped loop having a similar density and low-profile to provide a high degree of hook-loop engagement. Alternatively, a less dense hook field having at least some of the hooks having a higher profile (e.g., 900 hooks per square inch, with each hook 0.028 inches in height) can be used in conjunction with an unnapped loop having a similar profile but lower density to provide a degree of hook penetration through the loop base and also optionally a degree of hook-loop engagement to provide a robust closure. In one such embodiment, note that the hook field may have multiple hook heights (e.g., dual hook-height, where shorter hooks engage loop and taller hooks penetrate through loop base). In any such cases, the density of the loop can be adjusted to allow the hooks higher probability to reach the loop base material or penetrate through perforations or holes therein.
Example Hook-and-Hook and Channel-based Mechanical Bonds
As can be further seen, there may be a degree of orthogonal play associated with the hook-and-hook mechanical bond. In particular, d1 represents the potential backlash distance of the hook-hook connections making up the bond, in some configurations. Other such embodiments may be configured to provide a d1 of zero. In general, backlash in a hook-and-hook design can be relatively small, depending on the mating qualities of the corresponding hook fields. In addition, note that the hook stems can be made flexible, so that they resistively deform if the hook is compressed into the hook field base, as further shown in
In one specific example embodiment, the respective hook fields (552a-b and 554a-b) are implemented with a hook-and-hook configuration similar to that used in Press-Lok® brand products produced by Velcro USA Inc. U.S. Pat. Nos. 6,687,962, 8,225,467, 8,448,305, and 8,685,194, as well as U.S. Patent Publication Nos. 2013/0239371, 2013/0280474, and 2013/0318752 all disclose further details of example hook element configurations that can be used as well as forming methods. Each of these applications is herein incorporated by reference in its entirety. The hooks may have any number of configurations, as will be appreciated in light of this disclosure (e.g., any number of HTH hook styles from Velcro USA Inc. may be used, for instance).
As will be further appreciated in light of this disclosure, note that unidirectional hooks are not required for a hook-and-hook based closure. For instance, some Press-Lok® brand hook-and-hook products alternate the direction of hooks (e.g., from row to row) and such that the hooks engage in both or otherwise multiple directions. Such an alternating or multi-direction pattern can be used in a plate mounting system as provided herein. See, for instance,
Note how each of the embodiments in
In any such cases, the density of the hook field can be configured to provide a uniform distribution of pressure between the print plate and cylinder. In general, and without wishing to be held to any particular theory, it seems that a higher distribution of hooks translates to lower backlash and a thinner overall closure. Conversely, a lower distribution of hooks translates to higher backlash and a thicker overall closure. In more detail, hook fields that are densely populated tend to be relatively short and more rigid than hook fields that are less densely populated. Hook field densities may range, for example, from about 500 hooks per square inch to about 2000 hook per square inch, in accordance with some embodiments of the present disclosure. Example hook designs include HTH hook styles 22 and 29 from Velcro USA Inc, which have hook densities of about 900 and 1700 hooks per square inch, respectively. The 22-style hook is 0.028 inches in height and the 29-style hook is 0.02 inches in height. Customizations of these example hook designs to, for instance, reduce the hook return ratio (via mold change) and/or modify resiliency (via resin change) will be apparent in light of this disclosure.
Example Gear-Based Mechanical Bonds
In one embodiment, the gear-based mechanical fastener 621 is implemented as a gear tape that is applied to the non-print side of the print plate 609 using adhesive or some other suitable bonding mechanism (e.g., ultrasonic weld). Alternatively, the gear-based mechanical fastener field 621 can be used as a substrate upon which the print plate 609 is formed. The gear-based mechanical fastener 623 can be, for example, integrally formed on a print sleeve/cylinder 607, via an extrusion or molding process. Alternatively, the gear-based mechanical fastener 623 is implemented as a gear tape that is applied to the print cylinder/sleeve 607. The gear tape can be formed using, for example, molding or extrusion process, or processes similar to those used in making hooks as provided herein.
In any such cases, such a gear-based mechanical bond generally provides a lower durometer and can be further used in conjunction with foam layers to provide a degree of cushioning if so desired. Note that while the gear troughs and ridges transverse the cylinder in the depicted embodiment, other embodiments may include smaller/shorter such gear troughs and ridges configured in a sequential or array-like fashion. Further note the self-aligning quality associated with such gear-based plate mounting systems.
Example Elastic Mounting System
Note that such stretch qualities in the hook tape 710 may be transferred to the plate 709, which may in turn cause some distortion in the printed image. However, the degree of distortion may or may not be a problem. For instance, if the hook strain is small or slight, then the elastic nature of the hooks would result in a contraction after the applied force is removed (snap back, much like a rubber band). In other words, the elastic hook tape 710 material would attempt to rebound. This would minimize the strain and stretch and as a result, the impact on the plate 709 would be relatively small. Depending on the accuracy requirement and strain (stretch), this may be acceptable. Also, this elasticity would allow the hooks 725a to engage with the hook field 725b (or loop field, as the case may be) and improve the adhesion (peel) strength. Further note that in some places, the elastic hook tape 710 would rebound to its original aspect ratio and this would result in no or otherwise minimal printed image deformation.
Interlocking hook tape 712 provides a complimentary field of hooks 725b to engage with the hooks 725a of hook tape 710, and can be pre-mounted to the print cylinder for longer term use. As will be appreciated, such reusable qualities enable continuous repositioning and quick change-over processes by printer operator. In this specific example case, the opposing, interlocking nature of hook fields 725a and 725b (one way hooks, formed with processes similar to those used to form other molded hooks, as previously explained) prevents slippage during the rotational print process. Further note that such interlocking hook-and-hook or hook-to-channel designs may enable the print plate 709 to slide on and off the print cylinder for easier assembly, and may also provide a self-alignment quality (to reduce time spent on registration of print plate to print machine).
Angled Hooks with Pressure Based Adhesive
Vacuum, Suction, and Magnetic Based Mounting Systems
Plate Mounting Systems with Edge Lifting Inhibitor
As will be appreciated in light of this disclosure, hook-and-hook and hook-to-channel, and channel-to-channel mechanical bonds can be used at any location of the plate mounting systems provided herein. Such mechanical bonds can also be strategically used in problem areas susceptible to peeling or poor print quality, such as the seam and edges of the print plate. For instance,
Plate Mounting Systems with Integral Cushion
Note that, as used herein, a unidirectional hook field may have a plurality of hooks facing in the same direction, but yet a relatively small or otherwise targeted percentage of the hooks in that field may be facing in a different direction. This variance may be intentional (targeted) or unintentional (due to factors such as manufacturing oversight or unforeseen conditions, or otherwise). In some embodiments, the percentage of hooks facing in the same direction in a unidirectional hook field is about 50% or higher. In other embodiments, the percentage of hooks facing in the same direction in a unidirectional hook field is about 85% or higher, in some embodiments. In still other embodiments, the percentage of hooks facing in the same direction in a unidirectional hook field is about 95% or higher, in some embodiments. In one specific embodiment, 100% of the hooks in the unidirectional hook field are facing in the same direction. By ‘same direction’ it is meant that the hooks are within +/−25% of a target direction, or +/−20% of a target direction, or +/−15% of a target direction, or +/−10% of a target direction, or within +/−5% of a target direction, or within +/−2% of a target direction, or within +/−1% of a target direction in some embodiments. Thus, a precise same direction is not required, as will be appreciated.
Methodology
In the example embodiment shown, the mechanical fastening elements 2192 are depicted as hook and/or loop elements. In some such embodiments, the mechanical fastening elements 2192 are unidirectional hooks angled so as to lean in a direction that is generally opposite to the machine direction. In one such case, an intervening layer of foam material 2191 is extruded over the resulting unidirectional hook field 2192, to provide an integral cushion effect. Further details of how to provision a field of foam over a fastener field are provided in the previously incorporated U.S. Pat. No. 7,108,814. In another such case, the resulting unidirectional hook field 2192 is configured with flexible hook stems, to provide an integral cushion effect. In other embodiments, the mechanical fastening elements 2192 are a field of single height loops configured to engage a unidirectional hook field of the print cylinder/sleeve. In another such embodiment, the mechanical fastening elements 2192 are a field of dual-height loops configured to engage a unidirectional hook field of the print cylinder/sleeve, wherein the hooks engage with the lower loops and the upper loops provide an integral cushion effect. In another such embodiment, the mechanical fastening elements 1892 are a field of dual-height unidirectional hooks configured to engage another field of dual-height unidirectional hooks of the print cylinder/sleeve. In another such embodiment, the mechanical fastening elements 2192 are a field of dual-height unidirectional hooks configured to engage a field of dual-height loops of the print cylinder/sleeve. In other embodiments, the mechanical fastening elements 2192 comprise both hook-and-loop fields configured to engage complementary fields of the print cylinder/sleeve. Numerous such variations will be apparent in light of this disclosure. In any such cases, the fastener fields used in forming the mechanical bond (or some sub-set of those fastener fields) can be configured with an integral cushion effect as provided herein. Cushioning external to the mechanical bond may be provided as well, to either supplement the integral cushion effect or as the sole cushioning. Note that ‘external’ cushioning refers to cushioning that is not between the bases of the two interfacing fasteners of the mechanical bond, such as shown in
In still other embodiments, the mechanical fastening elements 2192 comprise other mechanical fasteners, such as channels or ridges or other such grabbing elements that can be molded or otherwise extruded and used in a male-female engagement to secure and/or self-align the print plate to a given print cylinder or sleeve. As will be further appreciated, a combination of mechanical fastening elements may be used as well, such as hooks and ridge, or hooks, channels, and loop. In any such cases, the extrusion, lamination, and molding techniques provided herein or otherwise referenced can be used to form the integrally formed structure, including methods provided in the previously incorporated U.S. Pat. Nos. 5,260,015, 6,687,962, 7,108,814, 8,225,467, 8,448,305, and 8,685,194, as well as U.S. Patent Publication Nos. 2013/0239371, 2013/0280474, and 2013/0318752.
Note that the depiction shown in
Further Example Embodiments
The following examples pertain to further embodiments, from which numerous permutations and configurations will be apparent.
Example 1 is a fastening system for mounting a print plate to a print cylinder, comprising: a first field of mechanical fasteners on one side of the print plate, the other side of the print plate for carrying a print design in relief; and a second field of mechanical fasteners for placement on or integration with the print cylinder. The first and second fields of mechanical fasteners operate together to provide a mechanical bond that inhibits lateral and rotational movement of the plate during printing operations, and is configured to manage backlash between engaging surfaces of the mechanical bond by way of at least one of a field of unidirectional fastening elements and a cushion effect integral with the mechanical bond itself.
Example 2 includes the subject matter of Example 1, wherein at least one of the first or second fields of mechanical fasteners comprises a field of unidirectional hooks.
Example 3 includes the subject matter of Example 2, wherein the unidirectional hooks are angled according to machine direction.
Example 4 includes the subject matter of Example 2 or 3, wherein the field of unidirectional hooks is provided on the print cylinder.
Example 5 includes the subject matter of any of Examples 2 through 4, wherein the field of unidirectional hooks is provided on the print plate.
Example 6 includes the subject matter of any of Examples 2 through 5, wherein the unidirectional hooks lean in a first direction, the system further comprising a second field of unidirectional hooks that lean in a second direction that is opposite the first direction.
Example 7 includes the subject matter of any of Examples 2 through 6, wherein the field of unidirectional hooks is at least partially covered in a cushion material that provides at least part of the cushion effect integral with the mechanical bond itself.
Example 8 includes the subject matter of any of the previous Examples, and further includes a cushion layer external to the mechanical bond that provides additional cushion effect.
Example 9 includes the subject matter of any of the previous Examples, and further includes a cushion layer integral with the mechanical bond that provides at least part of the cushion effect integral with the mechanical bond itself.
Example 10 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises hooks configured with flexible stems to resistively deform during at least one of engagement with the opposing mechanical fastener field and print operations, thereby providing at least part of the cushion effect integral with the mechanical bond itself.
Example 11 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises an unnapped loop field.
Example 12 includes the subject matter of Example 11, wherein unnapped loop field comprises two levels so as to provide a short loop height and a tall loop height.
Example 13 includes the subject matter of Example 12, wherein the tall loop height provides at least part of the cushion effect and the loops having the short height engage with a complementary hook field.
Example 14 includes the subject matter of any of the Examples 11 through 13, wherein one of the first or second fields of mechanical fasteners comprises a spacer fabric configured with loop-like engageability or a loop pile on at least one surface, thereby providing at least part of the cushion effect integral with the mechanical bond itself.
Example 15 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises a loop field and the other field comprises a hook field.
Example 16 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises a male feature and the other field comprises a female feature.
Example 17 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises a magnet and the other field comprises a surface to which a magnet can bond.
Example 18 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises a vacuum element and the other field comprises a surface to which a vacuum can bond.
Example 19 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises a suction cup and the other field comprises a surface to which a suction cup can bond.
Example 20 includes the subject matter of any of the previous Examples, wherein one of the first or second fields of mechanical fasteners comprises a first gear pattern and the other field comprises a second gear pattern that snugly engages with the first gear pattern.
Example 21 includes the subject matter of any of the previous Examples, wherein at least one of the first or second fields of mechanical fasteners is configured to prevent edge lifting of the plate.
Example 22 includes the subject matter of any of the previous Examples, wherein at least one of the first or second fields of mechanical fasteners comprises unidirectional hooks provisioned in an alternating pattern, such that a first row of hooks face in one direction and a next row of hooks face in another direction to provide a bi-directional or otherwise multi-directional hook field.
Example 23 includes the subject matter of any of the previous Examples, wherein at least one of the first or second fields of mechanical fasteners comprises unidirectional hooks, and wherein at least 85% of the hooks that field are facing in a target direction, plus or minus 15 degrees.
Example 24 is a print plate for a cylinder-based printing system, the plate comprising an integral field of mechanical fasteners that form a mechanical bond with a print sleeve or print cylinder having a corresponding field of mechanical fasteners. The plate may be configured, for instance, as variously indicated in any of the previous Examples 1 through 23.
Example 25 includes the subject matter of Example 24, wherein the print plate has a print side and a non-print side, the print side comprising a photopolymer material and the non-print side comprising a material that is laminated with the photopolymer material.
Example 26 is a print sleeve for a cylinder-based printing system, the plate sleeve comprising an integral field of mechanical fasteners that form a mechanical bond with a print plate having a corresponding field of mechanical fasteners. The print sleeve may be configured, for instance, as variously indicated in any of the previous Examples 1 through 23.
Example 27 includes the subject matter of Example 26, wherein the print sleeve is heat-shrinkable. Alternatively, the print sleeve may be elastic or otherwise stretchable.
Example 28 is a print cylinder for printing system, the cylinder comprising an integral field of mechanical fasteners that form a mechanical bond with a print plate having a corresponding field of mechanical fasteners, wherein at least part of the print cylinder and the integral field of mechanical fasteners are of a unitary mass of material. The print cylinder may be configured, for instance, as variously indicated in any of the previous Examples 1 through 23.
Example 29 is a method for forming a print plate for a cylinder-based printing system, the method comprising extruding a field of mechanical fasteners onto a print plate or a print plate blank. The print plate may be configured, for instance, as variously indicated in any of the previous Examples 1 through 25.
Example 30 includes a method for forming a print plate for a cylinder-based printing system, the method comprising co-extruding a field of mechanical fasteners and a print plate or print plate blank. The print plate may be configured, for instance, as variously indicated in any of the previous Examples 1 through 25.
Example 31 includes the subject matter of Example 29 or 30, further including laminating the structure resulting from the extrusion.
Example 32 includes the subject matter of any of Examples 29 through 31, further including forming a cushion layer over the field of mechanical fasteners.
Example 33 is a fastening system for mounting a print plate to a print cylinder, comprising: a first field of mechanical fasteners on one side of the print plate, the other side of the print plate for carrying a print design in relief; and a second field of mechanical fasteners for placement on or integration with the print cylinder. The first and second fields of mechanical fasteners operate together to provide a mechanical bond that inhibits lateral and rotational movement of the plate during printing operations, and is configured to manage backlash between engaging surfaces of the mechanical bond by way of unidirectional fastening elements. In addition, one of the first or second fields of mechanical fasteners comprises unidirectional hooks that are angled according to machine direction.
Example 34 includes the subject matter of Example 33, wherein the field of unidirectional hooks is at least partially covered in a cushion material.
Example 35 includes the subject matter of Example 33 or 34, further including a cushion layer integral with the mechanical bond.
Example 36 includes the subject matter of any of Examples 33 through 35, wherein the other one of the first or second fields of mechanical fasteners comprises an unnapped loop field.
Example 37 includes the subject matter of any of Examples 33 through 36, wherein at least 75% of the hooks of the first or second hook field are facing in a target direction, plus or minus 15 degrees.
Example 38 includes the subject matter of Example 37, wherein a percentage the hooks of the first or second hook field are facing in a direction opposite the target direction, plus or minus 15 degrees.
Example 39 is a print plate for a printing system, the plate comprising an integral field of mechanical fasteners that form a mechanical bond with a corresponding print machine element having a complementary field of mechanical fasteners. The print plate may be configured, for instance, as variously indicated in any of the previous Examples 1 through 25.
Example 40 includes the subject matter of Example 39, wherein the integral field of mechanical fasteners includes metal pieces embedded within the plate and proximate edges of the plate, and wherein concentration of the metal pieces at the edges is higher than a concentration of metal pieces elsewhere in the plate.
Example 41 includes the subject matter of Example 40, wherein the concentration of metal pieces elsewhere in the plate is less than 25 percent by volume.
Example 42 includes the subject matter of Example 40, wherein the concentration of metal pieces elsewhere in the plate is zero.
Example 43 includes the subject matter of Example 40, wherein the concentration of metal pieces elsewhere in the plate is in the range of 5 to 50 percent by volume, and the concentration of the metal pieces at the edges is in the range of 25 to 95 percent by volume.
Example 44 includes the subject matter of any of Examples 40 through 43, wherein at a given plate cross-section containing metal pieces, a remaining percent by volume not occupied by metal pieces is occupied by at least one of a photopolymer and cushion material.
Example 45 includes the subject matter of any of Examples 40 through 44, wherein the metal pieces comprise iron flake.
Example 46 includes the subject matter of any of Examples 39 through 45, wherein the integral field of mechanical fasteners are configured to provide at least two types of mechanical bonds, the types being selected from the group of hook-and-loop bond, hook-and-hook bond, hook-to-channel bond, male/female-type fitting bond, vacuum bond, suction bond, magnetic bond, and interlocking gear bond.
Example 47 includes the subject matter of any of Examples 39 through 46, wherein the integral field of mechanical fasteners is configured to provide a first mechanical bond proximate at least one edge of the plate and that first mechanical bond is stronger than bonds associated with other areas of the plate.
Example 48 includes the subject matter of Example 47, wherein the first mechanical bond is implemented with vacuum or suction and the bonds associated with other areas of the plate are implemented with magnetics.
Example 49 includes the subject matter of Example 47, wherein the first mechanical bond is implemented with magnetics and the bonds associated with other areas of the plate are implemented with vacuum or suction.
Example 50 includes the subject matter of Example 47, wherein the first mechanical bond is implemented with magnetics and the bonds associated with other areas of the plate are implemented with adhesive.
The foregoing description of example embodiments has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the disclosure be limited not by this detailed description, but rather by the claims appended hereto.
This application claims the benefit of and priority to U.S. Provisional Application No. 62/022,889, filed on Jul. 10, 2014, which is herein incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US15/40003 | 7/10/2015 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62022889 | Jul 2014 | US |
