EP0361393A2 - Méthode et appareil pour nettoyer une tête d'impression - Google Patents

Méthode et appareil pour nettoyer une tête d'impression Download PDF

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Publication number
EP0361393A2
EP0361393A2 EP89117753A EP89117753A EP0361393A2 EP 0361393 A2 EP0361393 A2 EP 0361393A2 EP 89117753 A EP89117753 A EP 89117753A EP 89117753 A EP89117753 A EP 89117753A EP 0361393 A2 EP0361393 A2 EP 0361393A2
Authority
EP
European Patent Office
Prior art keywords
face
print head
cavity
aperture
outlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP89117753A
Other languages
German (de)
English (en)
Other versions
EP0361393A3 (fr
Inventor
James C. Oswald
Jeffrey J. Anderson
Ted E. Deur
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tektronix Inc
Original Assignee
Tektronix Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tektronix Inc filed Critical Tektronix Inc
Publication of EP0361393A2 publication Critical patent/EP0361393A2/fr
Publication of EP0361393A3 publication Critical patent/EP0361393A3/fr
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/135—Nozzles
    • B41J2/165—Prevention or detection of nozzle clogging, e.g. cleaning, capping or moistening for nozzles
    • B41J2/16517—Cleaning of print head nozzles
    • B41J2/16552—Cleaning of print head nozzles using cleaning fluids
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/17—Ink jet characterised by ink handling
    • B41J2/175—Ink supply systems ; Circuit parts therefor
    • B41J2/17593—Supplying ink in a solid state

Definitions

  • This invention pertains to an apparatus and method for cleaning a printer print head, and in particular for cleaning of the aperture of an ink jet print head.
  • ink drops are produced on demand.
  • Exemplary drop-on-demand ink jet heads are illustrated in U.S. Patent No. 4,106,032 issued to Miura et al. and U.S. Patent No. 4,727,378 issued to Le et al. These ink jet heads produce an ink drop at an ink-drop-forming aperture. The ink drop is propelled through an air chamber toward a main external aperture of the ink jet head. Air under pressure is delivered to the air chamber and entrains the drop of ink in a generally coaxial air stream as the ink drop travels through the air chamber.
  • Apparatus has also been designed for cleaning the external face of the print head around the outer orifice. For instance physical wipers, such as squeegees and cloth wipes are moved across or blotted against the face. It is possible for such apparatus to leave some part of the cleaner substance in the aperture.
  • This device doesn't necessarily provide a well defined flow past the aperture for several reasons. Firstly, a seal is not developed between the cavity and the aperture face, so that the gas and ink carried by the gas can travel through the space between the print head and the body forming the cavity. Secondly, since a control volume for the impinging air stream from the air jet nozzle is not completely defined by solid boundaries, the air flow will be diverted in all directions when the air stream impinges upon the ink jet head. Thus, the gas flow is uncontrolled and tends to be dispersed. This dispersion creates inconsistency in the effectiveness of the fluid stream to carry the ink from the aperture.
  • the present invention provides an external ink jet print head cleaner that maintains controlled fluid flow into the cleaning region, around an ink jet aperture and out of that region without contacting the aperture region with a solid substance.
  • fluid refers to both liquid and gas.
  • a continuous well-defined passageway is provided that directs a fluid smoothly past the aperture so that the pressure, mass flow and directionality of the fluid is controlled in the vicinity of the aperture, thereby assuring effective removal of the ink drops in the area of the aperture and complete removal of ink from the print head.
  • a body having a first face placeable against the print head face.
  • This first face has an opening sized to surround the ink jet aperture when the first face is placed against the print head face.
  • Means are provided in the body which define a cavity extending along the opening and having an inlet disposed adjacent to one edge of the opening.
  • An outlet is disposed adjacent to a generally oppositely disposed edge of the opening.
  • the cavity preferably has a depth away from the opening less than the length of the opening between the inlet and outlet.
  • means are provided for directing a volume of a fluid through the inlet into the cavity and out the outlet.
  • the present invention also provides a method of cleaning the aperture disposed in the face of an ink jet print head.
  • This method includes enclosing the aperture of the print head with a cavity formed in a body with a first face having an opening facing the print head face, an inlet disposed adjacent to one edge of the opening, and an outlet disposed adjacent to a generally oppositely disposed edge of the opening.
  • a fluid supply is directed through the inlet and cavity at an angle that is substantially tangential to the aperture, and out the outlet, thereby carrying ink disposed around the apertures out through the outlet.
  • the present invention provides a simple, effective ink jet aperture cleaner.
  • the fluid directed substantially tangentially past the aperture is maintained in a controlled fashion in a substantially unidirectional flow by a reduced cavity forming an enclosure around the apertures.
  • Hot melt ink is thermally treated to melt it for deposition, with it then becoming solid upon cooling.
  • Other inks such as aqueous-based or oil-based inks can also be used, though small changes may be required to handle their constant liquid state.
  • an apparatus 10 is usable for cleaning a print head 12.
  • Apparatus 10 includes a body 14 formed of a shell member 16 and a backing member 18. If a hot melt type of ink is used, these members are preferably made of a material that is rigid at the operating temperatures.
  • Member 16 has what is referred to as a first planar face 16a in which is formed an opening 16b. This opening is sized to encompass the total vertical and horizontal dimensions of the array 20 of ink jet apertures of print head 12.
  • a pair of heater elements 17 and 19 are preferably mounted on the exposed faces of member 16 associated with face 16a, as shown, or on backing member 18.
  • Elements 17 and 19 are preferably a resistive serpentine heater within a KaptonTM tape sandwich, such as the commercially available MINCOTM foil heater. Such a heater assists in preventing significant cooling of the print head when it is in contact with body 14. These heaters are only necessary if the print head is operated at temperatures substantially above room temperature.
  • Backing member 18 has a portion 18a that is attached to corresponding back edges of member 16. Member 18 also comprises an insert portion 18b which extends inside member 16. Member 16 and member 18, in combination, form a passageway 22 consisting of a distribution chamber 24, inlet channel 26, head-­ cleaning cavity 28, outlet channel 30, and ink-­collection chamber 32. The ends of the members are sealed so that there is no communication between sections of the passageway other than as described.
  • An inlet hole 18c passes through member 18, as shown, to receive a tube coupling element 34 to which is attached an inlet tube 36.
  • tube 36 may be connected to a supply 38 of air under positive pressure relative to the ambient pressure around body 14, or to what is referred to as an air supply, which may simply be the ambient air.
  • the supply may be any suitable fluid, such as nitrogen gas.
  • a filter be placed between air source 38 and inlet channel 26.
  • air source 38 include a heater 39, such as heater coils positioned in the air path, so that the air passing through cavity 28 and contacting print head 12 is maintained in a heated condition to avoid significantly cooling the print head.
  • Distribution chamber 24, inlet channel 26 and the fluid supply preferably provide a substantially even pressure and mass flow along the length of the inlet channel.
  • a corresponding tube coupling element 40 and outlet tube 42 is coupled to discharge unit 44 that may simply be a discharge into the atmosphere, when a positive pressure supply 38 is used, or may be a subatmospheric pressure source, such as a vacuum pump.
  • discharge unit 44 may simply be a discharge into the atmosphere, when a positive pressure supply 38 is used, or may be a subatmospheric pressure source, such as a vacuum pump.
  • a pump 44 When a pump 44 is used, it also preferably comprises a filter for removing fine particulate matter between the outlet and the pump.
  • Body 14 is attached to a cleaner platform 46 which comprises a floor member 48 on which the body rests, a backing member 49 to which the body is attached.
  • the body is preferably attached to platform 46 by a resilient connection which allows the body to move angularly relative to the platform. In the embodiment shown, this is provided by a connecting copper plate 52 having opposite ends joined to member 49 and member 18, as shown.
  • the copper plate acts like a spring and allows the body to pivot about the plate, which runs along the length of the body.
  • Platform 46 is mounted to a printer frame 54 relative to which the print head is positionable for cleaning, as is conventionally provided at one end of the travel of the print head relative to a printing zone.
  • Platform 46, and body 14 are movable into cleaning position by appropriate drive means, such as an actuator 56 mounted between frame 54 and platform 48, and actuator 58 between platform 48 and body 14. Face 16a is brought against the face of the print head for cleaning by the use of the actuators and spring plate 52.
  • An exemplary head 12 includes a print face 12a.
  • Head 12 includes a plurality of ink jets 60 distributed in array 20 along print face 12a.
  • Each ink jet 60 as shown in Fig. 3, comprises an ink inlet 62, a piezoelectric element 64 for ejecting the ink, an ink chamber 66, and an ink aperture 68 out through which the ink is ejected.
  • the outer surface of face 12a adjacent the apertures is preferably coated with an anti-wetting material 70, such as the material sold under the proprietary name Teflon® by DuPont Corporation. Layer 70 may be deposited to form the surface of face 12a as described in copending application having Serial No. 215,126 and entitled "Modified Ink Jet Printing Head Method for Producing Ink Jet Printed Images".
  • the space between faces 12a and 16a is preferably as narrow as is reasonably possible, without the faces touching.
  • the space between these faces below aperture 68 is preferably closed. This may be accomplished by placing a length of KaptonTM tape 71 along the edge 16d forming one side of outlet channel so that it contacts face 12a during cleaning.
  • Other compliant structures, such as a silicon rubber lip, could also be used.
  • air is directed through inlet channel 26 into cavity 28 toward a point upstream, or in this case, above apertures 68. This assures that the gas will be flowing tangentially along face 12a past the apertures.
  • Face 16a of member 16 has a continuous groove 16c extending around opening 16b.
  • a resilient O-ring 74 is disposed in this groove.
  • print head 12 is brought into position adjacent to cleaner 10.
  • Cleaner 10 is then positioned by actuator 56 with the faces 16a and 12a flush.
  • O-ring 74 contacts face 12a so that cavity 28 is sealed off from the ambient environment.
  • the soft O-ring seal also prevents face 16a from damaging print head face 12a or coating 70 when apparatus 10 and print head 12 come in contact with each other.
  • inlet tube 36 is coupled to an air source, such as filtered ambient air.
  • Outlet tube 42 is coupled to a vacuum pump.
  • the present apparatus can also be used with a positive air source attached to the inlet with substantially the same results.
  • a positive air source attached to the inlet with substantially the same results.
  • the predominance of the subatmospheric pressure source, or vacuum pump creates a stronger seal between faces 12a and 16a, which assures the integrity of passageway 20.
  • outlet chamber 32 The ink that is picked up in cavity 28 by the passing fluid flow is deposited in outlet chamber 32.
  • the outlet channel is directed downwardly into the chamber so that the ink drips into the chamber from a lip 75 or is thrown against the chamber walls.
  • the air exiting the chamber then is substantially clear of entrained ink.
  • a drawer 76 is placed through an opening 16d in the end of member 16.
  • Drawer 76 rests on the bottom of chamber 32 and has sides that conform with the sides of chamber 32.
  • the exposed face 76a of the drawer has a handle 76b.
  • a seal gasket 78 is placed around drawer 76 between extended edges of face 76a and the associated face of member 16 around opening 16d.
  • a latch 80 is mounted to member 16 for securing drawer 76 in chamber 32. Latch 80 is turned to allow removal of the drawer.
  • Drawer 76 is preferably made of a flexible, heat resistent material, such as Teflon®. When the ink settles in the bottom of the drawer, it solidifies if it has not already done so. When the drawer is removed and flexed, the solidified ink is broken into pieces and dislodged from the drawer, thus facilitating removal
  • Cleaner 10 thus provides an effective method and apparatus for providing controlled fluid flow for removing residue ink from the face of an ink jet print head. Variations in the form and structure of the cleaner, and in the steps providing cleaning can be made without parting from the spirit and scope of the invention as defined by the claims.

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  • Ink Jet (AREA)
EP19890117753 1988-09-26 1989-09-26 Méthode et appareil pour nettoyer une tête d'impression Withdrawn EP0361393A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US24906688A 1988-09-26 1988-09-26
US249066 1988-09-26

Publications (2)

Publication Number Publication Date
EP0361393A2 true EP0361393A2 (fr) 1990-04-04
EP0361393A3 EP0361393A3 (fr) 1990-10-24

Family

ID=22941922

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890117753 Withdrawn EP0361393A3 (fr) 1988-09-26 1989-09-26 Méthode et appareil pour nettoyer une tête d'impression

Country Status (2)

Country Link
EP (1) EP0361393A3 (fr)
JP (1) JPH02108549A (fr)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1005997A1 (fr) * 1998-12-04 2000-06-07 Eastman Kodak Company Imprimante à jet d'encre auto-nettoyante à écoulement inverse et procédé d'assemblage de l'imprimante
EP1005998A1 (fr) * 1998-12-04 2000-06-07 Eastman Kodak Company Imprimante à jet d'encre auto-nettoyante à écoulement de fluide inversible et à ultrasons, et procédé d'assemblage de l'imprimante
EP1016530A1 (fr) * 1998-12-29 2000-07-05 Eastman Kodak Company Imprimante à jet d'encre avec cloison oscillante et procédé d'assemblage de l'imprimante
EP1088665A1 (fr) * 1999-09-28 2001-04-04 Eastman Kodak Company Système d'imprimante à jet d'encre auto-nettoyant à écoulement de fluide réversible et à rouleau tournant, et méthode d'assemblage du système d'imprimante
US6254216B1 (en) * 1997-07-01 2001-07-03 Marconi Data Systems Inc. Clean-in place system for an ink jet printhead
EP1162071A1 (fr) * 2000-06-08 2001-12-12 Illinois Tool Works Inc. Nettoyage d'un dispositif à jet de liquide
US6406125B1 (en) 2000-06-08 2002-06-18 Illinois Tool Works Inc. System and method for maintaining the front of a fluid jet device in a relatively clean condition
US6935721B2 (en) 2002-02-08 2005-08-30 Illinois Tool Works, Inc. Maintenance modules for fluid jet device
EP1945459A1 (fr) * 2005-10-10 2008-07-23 Silverbrook Research Pty. Ltd Procede d'entretien d'une tete d'impression par nettoyage a l'air force

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2804613B2 (ja) * 1990-07-24 1998-09-30 キヤノン株式会社 インクジェット記録方法およびその装置
JP2002046285A (ja) * 2000-08-04 2002-02-12 Naltec Inc 印刷用ヘッドのクリーニング装置およびクリーニング方法
JP5133788B2 (ja) * 2008-06-11 2013-01-30 理想科学工業株式会社 インクジェットプリンターのクリーニング装置
JP5133789B2 (ja) * 2008-06-11 2013-01-30 理想科学工業株式会社 インクジェットプリンターのクリーニング装置
JP5153556B2 (ja) * 2008-10-08 2013-02-27 キヤノン株式会社 クリーニング方法、クリーニング冶具およびクリーニング装置
JP4904420B2 (ja) * 2009-09-28 2012-03-28 パナソニック株式会社 インクジェット用のワイプ装置およびこれを用いたワイプ方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3019768A1 (de) * 1980-05-23 1981-12-03 Gunther M. 8918 Diessen Voss Neuartiger verschluss fuer beruehrungsfrei arbeitende tintendrucker
US4591870A (en) * 1985-04-12 1986-05-27 Eastman Kodak Company Ink jet printing apparatus and method with condensate-washing for print head
US4626869A (en) * 1985-04-12 1986-12-02 Eastman Kodak Company Ink jet wet-storage system
JPS6277939A (ja) * 1985-10-01 1987-04-10 Canon Inc インクジエツト記録装置の作動方法
US4734718A (en) * 1985-02-13 1988-03-29 Sharp Kabushiki Kaisha Ink jet printer nozzle clog preventive apparatus

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61193857A (ja) * 1985-02-22 1986-08-28 Nec Corp インクジエツトプリンタのヘツドクリ−ニング方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3019768A1 (de) * 1980-05-23 1981-12-03 Gunther M. 8918 Diessen Voss Neuartiger verschluss fuer beruehrungsfrei arbeitende tintendrucker
US4734718A (en) * 1985-02-13 1988-03-29 Sharp Kabushiki Kaisha Ink jet printer nozzle clog preventive apparatus
US4591870A (en) * 1985-04-12 1986-05-27 Eastman Kodak Company Ink jet printing apparatus and method with condensate-washing for print head
US4626869A (en) * 1985-04-12 1986-12-02 Eastman Kodak Company Ink jet wet-storage system
JPS6277939A (ja) * 1985-10-01 1987-04-10 Canon Inc インクジエツト記録装置の作動方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 11, no. 278 (M-623)(2725) 09 September 1987, & JP-A-62 77939 (H. TERASAWA) 10 April 1987, *

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6254216B1 (en) * 1997-07-01 2001-07-03 Marconi Data Systems Inc. Clean-in place system for an ink jet printhead
EP1005998A1 (fr) * 1998-12-04 2000-06-07 Eastman Kodak Company Imprimante à jet d'encre auto-nettoyante à écoulement de fluide inversible et à ultrasons, et procédé d'assemblage de l'imprimante
US6142601A (en) * 1998-12-04 2000-11-07 Eastman Kodak Company Self-cleaning ink jet printer with reverse fluid flow and method of assembling the printer
US6183057B1 (en) 1998-12-04 2001-02-06 Eastman Kodak Company Self-cleaning ink jet printer having ultrasonics with reverse flow and method of assembling same
EP1005997A1 (fr) * 1998-12-04 2000-06-07 Eastman Kodak Company Imprimante à jet d'encre auto-nettoyante à écoulement inverse et procédé d'assemblage de l'imprimante
EP1016530A1 (fr) * 1998-12-29 2000-07-05 Eastman Kodak Company Imprimante à jet d'encre avec cloison oscillante et procédé d'assemblage de l'imprimante
US6168256B1 (en) 1998-12-29 2001-01-02 Eastman Kodak Company Self-cleaning ink jet printer with oscillating septum and method of assembling the printer
US6290323B1 (en) 1999-09-28 2001-09-18 Eastman Kodak Company Self-cleaning ink jet printer system with reverse fluid flow and rotating roller and method of assembling the printer system
EP1088665A1 (fr) * 1999-09-28 2001-04-04 Eastman Kodak Company Système d'imprimante à jet d'encre auto-nettoyant à écoulement de fluide réversible et à rouleau tournant, et méthode d'assemblage du système d'imprimante
EP1162071A1 (fr) * 2000-06-08 2001-12-12 Illinois Tool Works Inc. Nettoyage d'un dispositif à jet de liquide
US6406125B1 (en) 2000-06-08 2002-06-18 Illinois Tool Works Inc. System and method for maintaining the front of a fluid jet device in a relatively clean condition
US6457802B2 (en) 2000-06-08 2002-10-01 Illinois Tool Works Inc. System and method for maintaining the front of a fluid jet device in a relatively clean condition
AU756643B2 (en) * 2000-06-08 2003-01-16 Illinois Tool Works Inc. System and method for maintaining the front of a fluid jet device in a relatively clean condition
US6739697B2 (en) 2000-06-08 2004-05-25 Illinois Tool Works, Inc. System and method for maintaining the front of a fluid jet device
US6935721B2 (en) 2002-02-08 2005-08-30 Illinois Tool Works, Inc. Maintenance modules for fluid jet device
EP1945459A1 (fr) * 2005-10-10 2008-07-23 Silverbrook Research Pty. Ltd Procede d'entretien d'une tete d'impression par nettoyage a l'air force
EP1945459A4 (fr) * 2005-10-10 2009-01-14 Silverbrook Res Pty Ltd Procede d'entretien d'une tete d'impression par nettoyage a l'air force

Also Published As

Publication number Publication date
EP0361393A3 (fr) 1990-10-24
JPH02108549A (ja) 1990-04-20

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