A printer for forming a full-width image on a receiver exclusive of a transverse side of the receiver, and method of assembling the printer

Abstract: A printer for forming a full-width image (20) on a receiver (30) exclusive of a transverse side (45a/b) of the receiver, and method of assembling the printer. The printer comprises an ink jet print head (50) adapted to eject a plurality of ink droplets (60) onto a receiver sheet for forming an image that extends a full-width (W) of the receiver sheet. To achieve this result, the print head commences ejection of ink droplets beginning at a predetermined distance (d) from a transverse side of the receiver sheet. A reservoir (180,190a,190b) is disposed adjacent the transverse side and along the predetermined distance for collecting ink droplets ejected along the predetermined distance, so that none of the ink droplets are inadvertently deposited onto the transverse side or onto components housed in the printer. In a preferred embodiment of the invention, the reservoir is an absorbent material that absorbs the ink droplets ejected along the predetermined distance. Alternatively, the reservoir can be a drain for collecting the ink droplets ejected along the predetermined distance. As another alternative, the ink droplets are caused to possess an electrostatic charge of a first polarity and the reservoir is caused to possess an electrostatic charge of a second polarity opposite the first polarity, so that the ink droplets ejected along the predetermined distance are preferentially attracted to the reservoir.

Description: BACKGROUND OF THE INVENTION This invention generally relates to ink jet printers and methods and more particularly relates to an ink jet printer for forming a full-width image on a receiver exclusive of a transverse side of the receiver, and method of assembling the printer. An ink jet printer produces images on a receiver by ejecting ink droplets onto the receiver in an imagewise fashion. The advantages of non-impact, low-noise, low energy use, and low cost operation in addition to the capability of the printer to print on plain paper are largely responsible for the wide acceptance of ink jet printers in the marketplace. Traditionally, prints were made with a blank border surrounding the printed image. However, today there is an established market for so-called "borderless" (i.e., full-width) prints. Borderless prints are aesthetically desirable because distracting borders around the image are nonexistent. Also, misaligned images cause uneven borders which are undesirable. Moreover, prints that are borderless when printed conserve print stock because there is then no need to trimaway the distracting border which would otherwise surround the image. A prior art technique for producing borderless prints is simply to begin operating a print head such that ink droplets commence ejection at a predetermined distance before the print head aligns with a marginal edge of the receiver. This prior art technique avoids the previously mentioned borders and thus provides borderless prints. However, use of this prior art technique gives rise to a problem. That is, when the print head is operated in this manner, ink droplets will also deposit onto a transverse side of the receiver and may even migrate to an underside of the receiver. Deposit of ink onto the transverse side as well as onto the underside of the receiver detracts from aesthetic enjoyment of the image. Moreover, commencing ejection of ink before the print head aligns with the marginal edge gives rise to yet another problem. In this regard, ink droplets not deposited onto the receiver are deposited elsewhere within the printer. Deposit of ink elsewhere in the printer may contaminate components contained in the printer, a highly undesirable result. It is therefore important to capture ink droplets not deposited onto the receiver during borderless printing, so that these ink droplets can be later easily removed from the printer for disposal or recycling. EP 0 707 973 A2 discloses an ink jet printer which uses a mesh type guide element for supporting the receiver sheet so that ink that is not deposited upon the receiver sheet is collected within a reservoir. Therefore, an object of the present invention is to provide a printer for forming a full-width image on a receiver exclusive of a transverse side of the receiver, and method of assembling the printer, such that inadvertent deposit of ink on the transverse side and elsewhere in the printer is avoided. SUMMARY OF THE INVENTION With the above object in view, the present invention is defined by the claims 1 and 9 appended hereto. According to an exemplary embodiment of the invention, the feature of the printer or method of forming an image on a receiver sheet that is characterized by a movable support comprising a pair of spaced-apart parallel belts each belt including a recessed lip for receiving the respective marginal side of the receiver sheet thereon and an upright wall of the lip that is spaced from a respective side edge of the receiver sheet. The upright wall is defined as being spaced from the receiver sheet's respective side edge by a gap that is less than the size of the smallest ink droplet ejected from the print head to block droplets falling into the gap and depositing onto the respective side edge of the receiver sheet. An advantage of the present invention is that use thereof provides borderless prints without transverse side ink contamination in order to enhance aesthetic enjoyment of the image formed on the receiver sheet. Another advantage of the present invention is that use thereof avoids ink contamination of components within the printer. These and other objects, features and advantages of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings wherein there are shown and described illustrative embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing-out and distinctly claiming the subject matter of the present invention, it is believed the invention will be better understood from the following description when taken in conjunction with the accompanying drawings wherein: Figure 1 is a view in elevation of a printer belonging to the present invention; Figure 2 is a view in plan of the printer taken along section line 2-2 of Figure 1; Figures 3A, 3B and 3C are views in elevation of a receiver sheet transport mechanism; Figure 4 is a view in perspective of the printer with parts removed for clarity, this view showing a reservoir in the form of a pair of spaced-apart parallel belts; Figure 5 is a view in elevation of a first embodiment of the reservoir; Figure 6 is an enlarged fragmentation view in elevation of the first embodiment reservoir; Figure 7 is a view in elevation of a second embodiment of the reservoir; Figure 8 is an enlarged fragmentation view in elevation of the second embodiment reservoir; and Figure 9 is a view in elevation of a third embodiment of the reservoir. DETAILED DESCRIPTION OF THE INVENTION Therefore, referring to Figs. 1 and 2, there is shown an ink jet printer, generally referred to as 10, for forming an image 20 on a receiver sheet 30 cut to a predetermined length from a roll of receiver 40. As described in more detail hereinbelow, printer 10 is adapted to form image 20 on receiver sheet 30 with no part of image 20 being formed on any of a plurality of transverse sides 45a and 45b of receiver sheet 30. Receiver sheet 30 has a plurality of marginal edges 46a and 46b bounding defining a full-width "W" of receiver sheet 30. Referring again to Figs. 1 and 2, printer 10 comprises a housing 47 containing a movable print head 50 adapted to eject an image-forming fluid, such as a plurality of ink droplets 60 (see Fig. 6), onto receiver sheet 30 to form image 20 thereon. It may be appreciated that ink droplets 60 may be a dye ink, a pigmented ink, or the like. It also may be appreciated that print head 50 may be a piezoelectric ink jet print head of a type well-known to those skilled in the art. More specifically, print head 50 may be formed of a piezoelectric material, such as lead zirconium titanate (PZT), mechanically responsive to electrical stimuli so that print head 50 deforms when electrically stimulated to eject ink droplets 60, as more fully described presently. In this regard, print head 50 includes a plurality of ink chambers 70, each chamber 70 being defined by a pair of oppositely disposed parallel side walls 80a and 80b. When any of the pairs of side walls 80a and 80b are electrically stimulated, such pair of side walls 80a and 80b simultaneously inwardly move to eject ink droplet 60 from chamber 70 (see Fig. 6). In order to form the desired image 20, the electrical stimuli supplied to print head 50 are controlled such that chambers 70 are selectively actuated for selectively ejecting ink droplets 60 from chambers 70. Still referring to Figs. 1 and 2, printer 10 further comprises a first motor 90 for rotating receiver roll 40, such as by means of a shaft 100 connected to first motor 90 and centrally engaging receiver roll 40. As receiver roll 40 rotates, a receiver supply 42 is unwound therefrom to pass between a pair of capstan rollers 110 which guide a desired amount of receiver supply 42 through a cutter blade mechanism 120. When the desired amount of receiver supply 42 passes through cutter blade mechanism 120, the cutter blade mechanism 120 is operated to cut receiver supply 42 in order to form the previously mentioned receiver sheet 30 of predetermined length. Referring to Figs. 1, 2, 3A, 3B and 3C, a transport mechanism, generally referred to as 125, engages receiver sheet 30 for transporting receiver sheet 30 relative to print head 50. In this regard, as receiver supply 42 unwinds from receiver roll 40, it passes between capstan rollers 110, through cutter blade mechanism 120 and onto a movable support, such as a movable platen 130, which is disposed near receiver roll 40. Thus, after cutter blade mechanism 120 cuts receiver supply 42 to form receiver sheet 30, momentum of receiver sheet 30 carries receiver sheet 30 onto platen 130 so that receiver sheet 30 comes to rest on platen 130. At this point, platen 130 supports receiver sheet 30. Moreover, an articulated arm 140 is connected to platen 130 for moving platen 130 along a predetermined path 145 relative to print head 50. Thus, it may be understood that receiver sheet 30 moves along predetermined path 145 as platen 130 moves because platen 130 supports receiver sheet 30. Arm 140 moves platen 130 along predetermined path 145 from a first position P1 to a second position P2, whereupon receiver sheet 30 leaves platen 130, as described in detail hereinbelow. However, to receive another receiver sheet 30, platen 130 must be returned to position P1. In this regard, arm 140 is operated such that platen 130 is caused to move from position P3 to position P4. Platen 130 is then caused to move from position P4 and back to position P1 to receive another receiver sheet 30. That is, movement of platen 130 through positions P1, P2, P3, P4 and back to position P1 is accomplished by articulated arm 140 which is controllably operated by a suitable second motor 150. Rotation of receiver roll 40, cutting of receiver supply 42, movement of print head 50 and platen 130 and articulation of arm 140 are controlled such that the desired image 20 is formed on receiver sheet 30 and such that receiver sheet 30 leaves platen 130 to be retrieved by an operator of printer 10. For this purpose, a controller 160 is preferably connected to print head 50, first motor 90, cutter blade mechanism 120 and second motor 150 for controlling these components of printer 10 in order to form the desired image 20 of receiver sheet 30 and to present the finished print to the operator of printer 10. Such a controller may be of a type available from Texas Instruments, Incorporated located in Dallas, Texas. It may be understood that print head 50 evinces reciprocating movement orthogonally with respect to platen 130 as platen 130 moves along path 145. More specifically, as platen 130 moves, print head 50 reciprocates between a first position X 1 and a second position X 2 along a direction illustrated by doubleheaded arrow 165. This is done in order to print each line of image information forming image 20. Of course, an ink supply 170 is connected to print head 50 for supplying ink to chambers 70 in print head 50. It is desirable to operate print head 50 such that image 20 extends the full width "W" of receiver sheet 30 in order to provide so-called "borderless" prints, if desired. Borderless prints are aesthetically desirable to the viewer of such a print because distracting borders around image 20 are absent. Also, misaligned images cause uneven borders which are undesirable. Moreover, borderless prints conserve receiver stock because the need to trim away a border surrounding image 20 to obtain a borderless print is avoided. A prior art solution to this problem is simply to begin operating print head 50 such that ink droplets 60 commence ejection beginning at a predetermined distance "d" (see Fig. 6) from transverse sides 45a or 45b (depending on direction of travel of reciprocating print head 50). This prior art technique avoids the previously mentioned borders and thus provides borderless prints. However, use of this prior art technique gives rise to a problem. That is, when print head 50 is operated in this manner, ink droplets 60 will deposit onto transverse sides 45a/b and may even migrate to an underside of receiver sheet 30. Deposit of ink onto transverse sides 45a and 45b as well as onto the underside of receiver sheet 30 detracts from aesthetic enjoyment of image 20. Moreover, commencing ejection of ink droplets 60 before print head 50 aligns with marginal edges 46a and 46b causes still another problem. In this regard, ink droplets not deposited onto receiver sheet 30 are deposited elsewhere within housing 47 to contaminate components contained therein, a highly undesirable result. It is therefore important to capture ink droplets not deposited onto receiver sheet 30, so that this ink can be later easily removed from printer 10 for disposal or recycling into ink supply 170. Therefore, referring to Figs. 4,5 and 6, a reservoir, generally referred to as 180, extends along predetermined distance "d" for receiving ink droplets 60 ejected along distance "d", so that transverse sides 45a/b and the underside of receiver sheet 30 are ink-free. Use of reservoir 180 also ensures that ink droplets 60 not deposited onto receiver sheet 30, which ink droplets 60 would otherwise contaminate components within housing 47, are instead captured by reservoir 180. According to a preferred embodiment of the invention, reservoir 180 comprises a pair of spaced-apart parallel belts 190a and 190b, each belt 190a/b being formed into a continuous loop (as shown). Extending around an inboard side of each belt 190a/b may be a lip portion 200 for mounting marginal edges 46a/b of receiver sheet 30 thereon. Belts 190a/b are preferable spaced-apart so that a gap 205 is formed between transverse side 45a/b and an upright wall of lip portion 200. Gap 205 has a predetermined width that is preferably less than the size of the smallest ink droplet 60 ejected from print head 50 to provide added assurance that no ink droplet 60 will fall into gap 205 and deposit onto transverse side 45a/b. However, even if some ink droplets 60 were to fall into gap 205, reservoir 180 nonetheless captures ink droplets 60 and draws such ink droplets 60 away from transverse sides 45a and 45b. In the preferred embodiment of the invention, reservoir 180 is a pad of absorbent material for absorbing, by capillary action, ink droplets 60 that are ejected along distance "d" and that may fall into gap 205. In this manner, no ink droplets 60 are deposited onto transverse sides 45a/b or elsewhere within housing 47. Ink landing on belts 190a/b is not only quickly absorbed by belts 190a/b, but also quickly dries to avoid deposit of the ink on subsequent receiver sheets 30. In this regard, the absorbent material may be a fibrous material, such as a polyester, a reticulated foam with open microscopic cells for receiving fluid, or the like. Of course, absorbent belts 190a/b may be periodically replaced by an operator of printer 10 once belts 190a/b become saturated with ink. Referring again to Figs. 4,5 and 6, a plurality of synchronized motorized rollers 210 engage respective ones of belts 190a/b for simultaneously rotating both belts 190a/b at the same velocity. Moreover, operation of rollers 210 are synchronized with movement of platen 130, so that belts 190a/b move in tandem with platen 130. At a point during rotation of belts 190a/b, receiver sheet 30 will leave belts 190a/190b to fall by force of gravity (see Fig. 1) into a receiver collection tray 215 for retrieval by an operator of printer 10. Turning now to Figs. 7 and 8, a second embodiment of the present invention is there shown. According to this second embodiment of the invention, reservoir 180 comprises a plurality of drains 220 facing print head 50 for receiving ink droplets 60 ejected along predetermined distance "d". To allow efficient collection of these ink droplets 60 ejected along predetermined distance "d", surfaces of reservoir 180 leading to drains 220 may be canted (as shown) to preferentially direct these ink droplets 60 into drain 220. Also, one or more of drains 220 may be in communication with gap 205 for collecting ink droplets that may have fallen into gap 205. Drains 220 are in communication with a suction pump 230, such as by means of a plurality of conduits 240 connected to respective ones of drains 220. The purpose of suction pump 230 is to suction ink droplets 60 through drains 220. Suction pump 230 is connected to a sump 250, such as by means of a pipe 260, which sump 250 receives ink droplets 60 suctioned by suction pump 230. Sump 250 may be periodically emptied by an operator of printer 10 once sump 250 fills with ink. As best seen in Fig. 9, a third embodiment of the present invention is there shown. According to this third embodiment of the invention, a first electrostatic source 270 is connected to print head 50 for electrifying ink droplets 60 ejected from channels 70. In this manner, ink droplets 60 obtain a first electrostatic charge of a first polarity (e.g., positive polarity). In addition, a second electrostatic source 280 is connected to reservoir 180 for electrifying reservoir 180, so that reservoir 180 obtains a second electrostatic charge of a second polarity (e.g., negative polarity) opposite the first polarity. In this manner, ink droplets 60 ejected along predetermined distance "d" are electrostatically preferentially attracted to reservoir 180 for capture. Of course, any ink droplets 60 falling into gap 205 are drawn to reservoir 180 and away from transverse sides 45a/b because such ink droplets are electrostatically attracted to reservoir 180. It may be appreciated from the description hereinabove, that an advantage of the present invention is that use thereof provides borderless prints without transverse side contamination in order to enhance aesthetic enjoyment of image 20 formed on receiver sheet 30. That is, production of borderless prints are now possible without ink being deposited on transverse sides 45a/b or on the underside of receiver sheet 30. This result is in turn due to ink ejected along distance "d" being captured by reservoir 180. It may be appreciated from the description hereinabove, that another advantage of the present invention is that use thereof avoids ink contamination of components within printer 10 during production of borderless prints. This is so because ink ejected along distance "d" is easily captured by reservoir 180 for later disposal or recycling. While the invention has been described with particular reference to its preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements of the preferred embodiments without departing from the invention. For example, the reservoir may be a radiant heater which evaporates the ink droplets ejected along the predetermined distance, such that no liquid ink droplets fall onto the transverse sides of the receiver sheet. Any ink particulate matter resulting from the evaporation process will deposit onto the reservoir for later disposal. In this instance, the reservoir may be coated with a suitable adhesive to bound the falling particulate matter to the reservoir to avoid migration of the particulates to the print or printer components and also for ease of disposal. Therefore, what is provided is an ink jet printer and method for forming a full-width image on a receiver exclusive of a transverse side of the receiver such that inadvertent deposit of ink on the transverse side and elsewhere in the printer is avoided.

Claims: A printer for forming an image (20) on a receiver sheet (30), comprising: (a) a print head (50) adapted to eject a plurality of droplets (60) upon a moving receiver sheet having respective opposite side edges that are parallel to the direction of movement of the receiver sheet; (b) a movable support engaging the receiver sheet for supporting the receiver sheet thereon for movement in said direction of movement; and characterized by : the movable support comprising a pair of spaced-apart parallel belts (190a,b) each belt including a recessed lip for receiving a respective marginal side of the receiver sheet thereon and an upright wall of the lip that is spaced from a respective side edge of the receiver sheet, the upright wall being spaced from the receiver sheet respective side edge by a gap that is less than the size of the smallest ink droplet ejected from the print head to block droplets falling into the gap and depositing onto the respective side edge of the receiver sheet. The printer of claim 1, wherein said belt comprises an absorbent pad for absorbing the ink droplets ejected onto the belt. The printer of claim 1, wherein said belt comprises a drain (220) for receiving the ink droplets thereinto; and a suction pump (230) is connected to said drain for suctioning the ink droplets received into said drain; and a sump (250) is connected to said pump for receiving the ink droplets suctioned by said pump. The printer of claim 1, further comprising: (a) a first electrostatic source (270) connected to said print head for electrifying the ink droplets ejected therefrom, so that the ink droplets have a first electrostatic charge of a first polarity; and (b) a second electrostatic source (280) connected to said belt for electrifying said belt, so that the belt has a second electrostatic charge of a second polarity opposite the first polarity, whereby the ink droplets ejected onto the belt near the side edge of the receiver sheet are preferentially attracted to said belt. The printer of any of claims 1-4, further comprising: (a) a platen support (130) and an articulated arm (140) connected to said platen support for moving said platen support along a predetermined path (145), so that the receiver moves along a portion of the predetermined path as the platen support moves; and (b) a motor (150) engaging said arm for articulating said arm. The printer of any of claims 1-5,wherein each said belt is formed into a loop. The printer of any of claims 1-6, further comprising a plurality of motorized rollers (210) engaging respective ones of said belts for rotating said belts, said rollers capable of rotating said belts so that said belts move in tandem. The printer of any of claims 1-7 and wherein the print head traverses across the receiver sheet in a direction transverse to movement of the receiver sheet and prints an image on the receiver sheet without leaving a blank border on the respective marginal sides of the receiver sheet. A method of forming an image on a receiver sheet, comprising: (a) ejecting a plurality of droplets from a print head upon a moving receiver sheet having respective opposite side edges that are parallel to the direction of movement of the receiver sheet; (b) engaging the receiver sheet upon a support that supports the receiver sheet thereon for movement in said direction of movement; and characterized by wherein the support comprises a pair of spaced-apart parallel belts each belt including a recessed lip, and wherein a marginal side of the receiver sheet is supported for said movement in the recessed lip of each belt, the recessed lip including an upright wall that is spaced from a respective side edge of the receiver sheet, the upright wall being spaced from the receiver sheet respective side edge by a gap that is less than the size of the smallest ink droplet ejected from the print head and blocking droplets falling into the gap and depositing onto the respective side edge of the receiver sheet. The method of claim 9 and wherein each belt includes an absorbent material that absorbs ink droplets ejected thereupon. The method of claim 9 and wherein each belt includes a drain for receiving the ink droplets deposited thereon and a suction pump removes ink droplets received into the drain. The method of claim 9 and wherein the ink droplets have a first electrostatic charge of a first polarity and each belt is electrified with a second electrostatic charge of a second polarity opposite the first polarity, whereby ink droplets ejected from the print head at locations above the belts are preferentially attracted to the belts and not to the side edges of the receiver sheet. The method of any of claims 9-12 and wherein the print head traverses across the receiver sheet in a direction transverse to movement of the receiver sheet and prints an image on the receiver sheet without leaving a blank border on the respective marginal sides of the receiver sheet.

Inventors: CAPURSO ROBERT G, CAPURSO, ROBERT G., Capurso, Robert G., c/o Eastman Kodak Company
Applicants: EASTMAN KODAK CO, EASTMAN KODAK COMPANY
Application year: 1999
Main classification: B41J2
IPC codes: B41J2, B41J11