EP1291729B1 - Bilderzeugungsgerät mit Einheiten zum Entfernen von Papierstaub - Google Patents

Bilderzeugungsgerät mit Einheiten zum Entfernen von Papierstaub Download PDF

Info

Publication number
EP1291729B1
EP1291729B1 EP02020402.0A EP02020402A EP1291729B1 EP 1291729 B1 EP1291729 B1 EP 1291729B1 EP 02020402 A EP02020402 A EP 02020402A EP 1291729 B1 EP1291729 B1 EP 1291729B1
Authority
EP
European Patent Office
Prior art keywords
paper dust
dust removing
paper
sheet
image forming
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.)
Expired - Lifetime
Application number
EP02020402.0A
Other languages
English (en)
French (fr)
Other versions
EP1291729A3 (de
EP1291729A2 (de
Inventor
Takeshi Fuwazaki
Makoto Hattori
Kazushi Fukuta
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.)
Brother Industries Ltd
Original Assignee
Brother Industries Ltd
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
Priority claimed from JP2001274323A external-priority patent/JP4429555B2/ja
Priority claimed from JP2001274325A external-priority patent/JP4203785B2/ja
Priority claimed from JP2002067642A external-priority patent/JP3835318B2/ja
Priority claimed from JP2002067641A external-priority patent/JP3750618B2/ja
Application filed by Brother Industries Ltd filed Critical Brother Industries Ltd
Publication of EP1291729A2 publication Critical patent/EP1291729A2/de
Publication of EP1291729A3 publication Critical patent/EP1291729A3/de
Application granted granted Critical
Publication of EP1291729B1 publication Critical patent/EP1291729B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H5/00—Feeding articles separated from piles; Feeding articles to machines
    • B65H5/06—Feeding articles separated from piles; Feeding articles to machines by rollers or balls, e.g. between rollers
    • 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
    • B41J13/00—Devices or arrangements of selective printing mechanisms, e.g. ink-jet printers or thermal printers, specially adapted for supporting or handling copy material in short lengths, e.g. sheets
    • B41J13/02—Rollers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H37/00—Article or web delivery apparatus incorporating devices for performing specified auxiliary operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H5/00—Feeding articles separated from piles; Feeding articles to machines
    • B65H5/06—Feeding articles separated from piles; Feeding articles to machines by rollers or balls, e.g. between rollers
    • B65H5/062—Feeding articles separated from piles; Feeding articles to machines by rollers or balls, e.g. between rollers between rollers or balls
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/65—Apparatus which relate to the handling of copy material
    • G03G15/6555—Handling of sheet copy material taking place in a specific part of the copy material feeding path
    • G03G15/6558—Feeding path after the copy sheet preparation and up to the transfer point, e.g. registering; Deskewing; Correct timing of sheet feeding to the transfer point
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2301/00—Handling processes for sheets or webs
    • B65H2301/50—Auxiliary process performed during handling process
    • B65H2301/51—Modifying a characteristic of handled material
    • B65H2301/511—Processing surface of handled material upon transport or guiding thereof, e.g. cleaning
    • B65H2301/5115—Cleaning
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2301/00—Handling processes for sheets or webs
    • B65H2301/50—Auxiliary process performed during handling process
    • B65H2301/53—Auxiliary process performed during handling process for acting on performance of handling machine
    • B65H2301/531—Cleaning parts of handling machine
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2301/00—Handling processes for sheets or webs
    • B65H2301/50—Auxiliary process performed during handling process
    • B65H2301/53—Auxiliary process performed during handling process for acting on performance of handling machine
    • B65H2301/532—Modifying characteristics of surface of parts in contact with handled material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2404/00—Parts for transporting or guiding the handled material
    • B65H2404/10—Rollers
    • B65H2404/13—Details of longitudinal profile
    • B65H2404/131—Details of longitudinal profile shape
    • B65H2404/1316—Details of longitudinal profile shape stepped or grooved
    • B65H2404/13162—Helicoidal grooves
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
    • G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
    • G03G15/1665—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/23—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 specially adapted for copying both sides of an original or for copying on both sides of a recording or image-receiving material
    • G03G15/231—Arrangements for copying on both sides of a recording or image-receiving material
    • G03G15/232—Arrangements for copying on both sides of a recording or image-receiving material using a single reusable electrographic recording member
    • G03G15/234—Arrangements for copying on both sides of a recording or image-receiving material using a single reusable electrographic recording member by inverting and refeeding the image receiving material with an image on one face to the recording member to transfer a second image on its second face, e.g. by using a duplex tray; Details of duplex trays or inverters
    • G03G15/235—Arrangements for copying on both sides of a recording or image-receiving material using a single reusable electrographic recording member by inverting and refeeding the image receiving material with an image on one face to the recording member to transfer a second image on its second face, e.g. by using a duplex tray; Details of duplex trays or inverters the image receiving member being preconditioned before transferring the second image, e.g. decurled, or the second image being formed with different operating parameters, e.g. a different fixing temperature
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/00362—Apparatus for electrophotographic processes relating to the copy medium handling
    • G03G2215/00535—Stable handling of copy medium
    • G03G2215/00607—Debris handling means

Definitions

  • the present invention relates to an image forming device such as a laser printer.
  • An image forming device such as a laser printer generally includes a sheet supply section for supplying sheets and an image forming section for forming an image on a sheet supplied from the sheet supply section.
  • the sheet supply section generally includes a sheet supply tray on which a stack of sheets is mounted, a sheet supply roller positioned near one end and above the sheet supply tray, and a separation pad positioned in confrontation therewith. Upon rotation of the sheet supply roller, an uppermost sheet on the sheet supply tray is nipped between the sheet supply roller and the separation pad and is delivered to the image forming section.
  • the image forming section includes a photosensitive drum, a charger, a scanner device, a developing roller and an image transfer roller those positioned around the photosensitive drum and in order in a rotating direction thereof.
  • a surface of the photosensitive drum is uniformly charged by the charger, and then, the surface is exposed to laser beam emitted from the scanner device and scanned at high speed in accordance with image data to form an electrostatic latent image on the surface.
  • toners carried on the developing roller are supplied to the surface of the photosensitive drum by the rotation of the developing roller to form a visible toner image on the surface of the photosensitive drum corresponding to the electrostatic latent image.
  • the toner image carried on the surface of the photosensitive drum is then transferred onto the sheet supplied from the sheet supply section when the sheet passes between the photosensitive drum and the image transfer roller.
  • a toner image can be formed on the sheet.
  • paper dusts may be inevitably generated on the sheet due to the friction against the separation pad because each sheet is supplied while being nipped between the sheet supply roller and the separation pad. Thus, image quality may be lowered, if such paper dusts are mixed with the toners at the image forming section.
  • a paper dust removing roller disposed upstream of the sheet supply roller.
  • the paper dust removing roller has a width approximately the same as that of the separation pad in order to remove the paper dust on the sheet before the sheet reaches the image forming section.
  • paper dusts have already inherently existed over the entire surface of the sheet due to sheet cutting. Therefore, it would be difficult to remove the inherent paper dusts only by such paper dust removing roller having the width the same as that of the separation pad.
  • Both inherently generated paper dusts as well as the paper dusts generated due to the friction with the separation pad may be removed by a paper dust removing roller as far as the paper dust removing roller has a width the same as the sheet width.
  • amount of the paper dust generated by the friction against the separation pad is greater than the inherently generated amount. Therefore, even if the removal of the paper dust is intended by such paper dust removing roller having the paper width, paper dust cannot be removed uniformly, but removal unevenness occurs between an area where paper dusts were generated due to the friction against the separation pad and an area where the paper dusts have been inherently generated. Thus, uniform removal of the paper dusts cannot be achieved.
  • a plurality of paper dust removing rollers can be provided along a sheet supply path in order to remove the paper dust on the sheet supplied from the sheet supply section.
  • a paper dust transport mechanism and a paper dust accumulator are provided for every paper dust removing roller for transporting and accumulating paper dusts removed by each paper dust removing roller. Therefore, an entire structure becomes complicated, and mechanical components and parts are increased, which renders a resultant image forming device bulky and costly.
  • a copier/printer having a transfer station for transferring images from an imaging member to copy sheets, which includes the improvement of removing debris from the surfaces of copy sheets facing the imaging member before the copy sheets reach the transfer station.
  • At least a pair of cooperating rolls are positioned to form a nip for driving the copy sheets therebetween toward the transfer station.
  • the cooperating rolls include a drive roll and a dielectric roll with the dielectric roll being electrostatically charged by the drive roll and paper through contact and separation during the intercopy gaps between copy sheets in transition to the transfer station through contact with the copy sheets to electrostatically attract depress from the copy sheets.
  • an apparatus for separating of sheets which comprises transport means for exerting a force on an outermost sheet of a pack of sheets in a direction of transport and separation means for exerting a force on at least one other sheet of the pack against the direction of transport to prevent the other sheet from moving along with the outermost sheet in the direction of transport. Because the apparatus comprises a treating device for treatment of the engaging surface of the transport means and/or the separation means to increase the roughness of the rough surface, a more reliable separation effect can be obtained especially over a longer period.
  • Another object of invention is to provide such image forming device with a simplified arrangement and capable of reducing numbers of mechanical parts, yet performing a sufficient paper dust removal by a plurality of paper dust removing units.
  • Still another object of the present invention is to provide such image forming device capable of stably transporting, by way of the paper dust transport means, the paper dusts removed by the paper dust removing unit to assure a sufficient falling distance between the paper dust removing unit and the paper dust transport means in order to unit and the paper dust transport means in order to provide a sufficient paper dust accumulation space below the paper dust removing unit.
  • Still another object of the present invention is to provide such image forming device capable of preventing paper dusts absorbed by the paper dust removing unit from again returning back to a sheet transport path in order to avoid mixture of the paper dusts with developing agent such as toners in a image forming operation performed at downstream of the paper dust removing unit.
  • an image forming device for forming an image on an image recording medium, the device including a sheet supply section, an image forming section, a sheet transport path, and an improved at least two paper dust removing units.
  • the sheet supply section includes a sheet supply roller and a separation pad for nippingly supplying each image recording medium therebetween.
  • the image forming section is adapted for forming an image on the image recording medium supplied from the sheet supply section.
  • the sheet transport path extends from the sheet supply section to the image forming section and defines a sheet feeding direction.
  • the at least two paper dust removing units include a first paper dust removing unit and a second paper dust removing unit.
  • the first paper dust removing unit is disposed at a position beside the sheet transport path and is contactable with the image recording medium for removing paper dusts from the image recording medium running in the sheet transport path toward the image forming section.
  • the second paper dust removing unit is disposed at a position beside the sheet transport path and different from the position of the first paper dust removing unit with respect to the sheet feeding direction and also is contactable with the image recording medium for also removing paper dusts from the image recording medium running in the sheet transport path toward the image forming section.
  • the first paper dust removing unit includes a first paper dust removing member in contact with the image recording medium during its travel in the sheet transport path
  • the second paper dust removing unit includes a second paper dust removing member in contact with the image recording medium during its travel in the sheet transport path.
  • the first paper dust removing member has a width perpendicular to the sheet feeding direction greater than the width of the separation pad
  • the second paper dust removing unit has a width perpendicular to the sheet feeding direction greater than the width of the image recording medium.
  • the width of the first paper dust removing member is smaller than the width of the image recording medium.
  • the first paper dust removing member can remove paper dusts from the image recording medium at least in an area corresponding to the width of the separation pad.
  • the second paper dust removing unit can remove paper dusts in overall surface of the image recording medium.
  • the image forming device preferably further provides a paper dust accumulating section for congregately accumulating therein paper dusts removed by at least two paper dust removing units from the image recording mediums and then released from the respective paper dust removing units.
  • the image forming device includes, the image forming section, a sheet transport path extending to the image forming section, a paper dust removing member, a scraping member, and a reverse transport preventive member.
  • the paper dust removing member is positioned in confrontation with the sheet transport path and contactable with the image recording medium passing therethrough for removing paper dusts from the image recording medium.
  • the scraping member is in contact with the paper dust removing member for scraping off the paper dusts from the paper dust removing member.
  • the paper dust removing member is supported rotatably in a normal direction equivalent to the sheet feeding direction and a reverse direction opposite to the normal direction.
  • the reverse transport preventive member is disposed between a first contact position defined between the paper dust removing member and the image recording medium and a second contact position defined between the paper dust removing member and the scraping member for preventing the paper dusts released from the scraping member from being transported back toward the sheet transport path during the reverse rotation of the paper dust removing member.
  • a paper dust transport unit and a regulation wall.
  • the paper dust transport unit is disposed lower than the first paper dust removing unit for transporting in a paper dust transporting direction the paper dusts falling down from the paper dust removing unit.
  • the regulation wall is disposed at a part of the paper dust transport unit for regulating a flow of the paper dusts.
  • the printer 1 includes a main casing 2, a feeder portion 4 for feeding a sheet 3 as an image recording medium, and an image forming section 5 for forming an image on the fed sheet 3.
  • the feeder portion 4 and the image forming section 5 are installed in the casing 2.
  • the feeder portion 4 includes a sheet supply tray 6 positioned on a bottom of the main casing 2 and detachable therefrom, a sheet supply section 7 disposed at one side of the sheet supply tray 6, a sheet mount plate 8 disposed in the sheet supply tray 6, a first transport portion 9 (a first paper dust removing unit), a second transport portions 10 (a second paper dust removing unit), and a register roller 11.
  • the first and second transport portions 9 and 10 are positioned at a downstream side of the sheet supply section 7 in a sheet feeding direction.
  • the register roller 11 is positioned downstream of the first and second transport portions 9,10.
  • the sheet supply tray 6 is of a box shape with an upper open construction so as to accommodate therein a stack of sheets 3.
  • the sheet supply tray 6 is slidable with respect to the bottom of the main casing 2, so that the tray 6 is detachable from the casing 2.
  • the sheet supply section 7 includes a sheet supply roller 12 and a separation pad 13 in confrontation therewith.
  • the separation pad 13 includes a support frame 13a, a pad member 13b, and a spring 13c.
  • the support frame 13a has generally L-shape in cross-section including a flat member positioned immediately below the sheet supply roller 12 and a support member extending downwardly from one side edge of the flat member and bent at a right angle with respect to the flat member. A lower end portion of the support member is pivotally connected to the main casing 2.
  • the pad member 13b is embedded in one surface of the flat member to confront with the sheet supply roller 12.
  • the flat member has an opposite surface to which the spring 13c is seated for urging the pad member 13b toward the sheet supply roller 12.
  • the pad member 13b has a generally rectangular shape and is formed of an elastic material such as a polyurethane rubber. As shown in Fig. 3(a) and 3(d) , the pad member 13b has a width B in a direction perpendicular to the sheet feed direction smaller than a width A of the sheet, the width A being a maximum width of the sheet undergoing printing by the laser printer 1. The pad member 13b is in contact with at least a widthwise center portion of the sheet 3 for the sheet supply.
  • a sheet mount plate 8 is adapted for mounting thereon the sheet stack.
  • the sheet mount plate 8 has a rear end pivotally connected to the sheet supply tray 6 and a front free end movable in a vertical direction.
  • a compression spring (not shown) is provided below the sheet mount plate 8 for normally urging the sheet mount plate 8 upwardly. Therefore, if sheet stack amount on the sheet mount plate 8 is increased, the free end of the sheet mount plate 8 is pivotally moved downwardly about the rear pivot axis against the biasing force of the compression spring (not shown).
  • An uppermost sheet 3 on the sheet stack on the sheet mount plate 8 is urged toward the sheet supply roller 12 because of the biasing force of the compression spring associated with the sheet mount plate 8.
  • Upon rotation of the sheet supply roller 12 a leading end portion of the uppermost sheet is nipped between the sheet supply roller 12 and the pad member 13b. In this manner each uppermost sheet is separated from the sheet stack and is delivered.
  • the sheet supply section 7 employs the friction/separation system and provides the following relationship in the friction force at the sheet supply timing. That is, frictional force between the sheet supply roller 12 and the sheet 3 is greater than the frictional force between the pad member 13b and the sheet 3, and the latter frictional force is greater than the frictional force between overlapping sheets.
  • the sheet is delivered to the register roller 11 through a sheet transport path 38 between the sheet supply section 7 and the image forming section 5 by way of first and second transport portions 9 and 10 described later.
  • the register roller 11 includes a pair of rollers for correcting diagonal feeding of the sheet 3 so as to feed the sheet 3 in a correct orientation to the image forming section 5.
  • the image forming section 5 includes a scanner portion 17, a process unit 18, and a fixing portion 19.
  • the scanner portion 17 is disposed at an upper interior portion of the main casing 2, and includes a laser emitting portion (not shown), a rotatably driven polygon mirror 20, lenses 21a, 21b, and a reflection mirror 22,
  • the laser beam according to image data is emitted from the laser emitting portion and is scanningly irradiated at high speed onto a surface of the photosensitive drum 23 of the process unit 18 through an optical path as shown by a dotted chain line in Fig. 1 defined by the polygon mirror 20, the lenses 21a, the reflection mirror 22 and the lens 21b.
  • the process unit 18 is disposed below the scanner portion 17 and is provided detachable from the main casing 2.
  • the process unit 18 includes a drum cartridge and a developing cartridge 24.
  • the drum cartridge houses therein the photosensitive drum 23 serving as a photosensitive member, an image transfer roller 25, and a scorotoron charger 37.
  • the developing cartridge 24 is detachable from the drum cartridge and houses therein a toner hopper 26. the developing roller 27, a toner layer thickness regulation blade 28, and a toner supply roller 29.
  • the toner hopper 26 positively chargeable non-magnetic single component type polymerized toners are filled as the developing agents.
  • Such toners are supplied to the developing roller 27 by the toner supply roller 29, and are carried on the developing roller 27 as a constant thin thickness toner layer because of frictional sliding relation with the toner layer thickness regulation blade 28.
  • the photosensitive drum 23 is rotatably disposed in confronting relation to the developing roller 27.
  • the photosensitive drum 23 includes a drum body which is grounded, and a positively chargeable photosensitive layer made from polycarbonate formed over the drum body.
  • the surface of the drum 23 is uniformly charged with positive polarity by means of the scorotoron charger 37, and is subjected to exposure to laser beam scanningly emitted from the scanner portion 17 at high speed according to the print data, whereupon electrostatic latent image is formed on the photosensitive surface.
  • the toner carried on the developing roller 27 and charged with positive polarity is supplied to the exposed part of the photosensitive drum 23, the potential level of the exposed part being lower than that of the remaining part of the photosensitive drum surface uniformly positively charged.
  • a visible toner image is formed on the photosensitive drum 23 to complete a reverse image developing.
  • the transfer roller 25 is positioned immediately below the photosensitive drum 23.
  • the transfer roller 25 includes a rotation shaft made of a metal and connected to an electrical power source, and an electrically conductive rubber layer formed over the rotation shaft.
  • a predetermined transfer bias voltage is applied to the rotation shaft for the toner transfer from the photosensitive drum 23 to the sheet 3.
  • the visible toner image is transferred onto the sheet 3, which is then delivered to the fixing portion 19 through a transport belt 30.
  • the fixing unit 19 is positioned beside the process unit 18 and downstream side of the process unit 18.
  • the fixing unit 19 includes a heat roller 31, a pressure roller 32 in pressure contact with the heat roller 31, and a feed roller 33 positioned downstream of the heat roller 31 and the pressure roller 32.
  • the heat roller 31 is made from a metal and is provided with a halogen lamp as a heat source.
  • the toner image transferred onto the sheet 3 at the process unit 18 is thermally fixed to the sheet 3 when the image carrying sheet passes through the heat roller 31 and the pressure roller 32.
  • the sheet 3 is then delivered to a downstream side feed roller 34, a discharge roller 35 disposed in the main casing 2 by way of the feed roller 33.
  • the sheet 3 fed by the downstream side feed roller 34 is discharged onto a discharge tray 36 by way of the discharge roller 35.
  • This toner collection manner is so called a cleaner-less system in which a blade for wiping out the residual toner and a residual toner container can be dispensed with, to simplify an overall arrangement of the image forming device.
  • a sheet re-circulation unit 41 is provided for forming images on both surfaces of the sheet 3.
  • the re-circulation unit 41 includes a sheet reverse section 42 and a re-circulation tray 43 integrally therewith.
  • the re-circulation unit 41 is positioned at a rear wall of the main casing 2 in such a manner that the sheet reverse section 42 is attached beside the rear wall, and the re-circulation tray 43 is detachably insertedly assembled into the rear wall at a position above the feeder section 4.
  • the sheet reverse section 42 has a casing 44 having a rectangular cross-section and attached to the rear wall of the main casing 2.
  • a flapper 45 In the casing 44, a flapper 45, reverse rollers 46 and re-circulation rollers 47 are provided. Further, a reverse guide plate 48 extends upwardly from an upper end portion of the casing 44.
  • the flapper 45 is pivotably provided at the rear portion of the main casing 2 and is positioned at a downstream side of the feed roller 33.
  • the flapper 45 is pivotally moved upon energization or deenergization of a solenoid (not shown) for switching a feeding direction of the one-sided image carrying sheet 3 fed by the feed roller 33 either to the downstream feed roller 34 as shown by a solid line or to the reverse rollers 46 as shown by a broken line.
  • the reverse rollers 46 include a pair of rollers and are positioned downstream of the flapper 45 and at an upper portion of the casing 44. Rotational direction of the reverse rollers is changeable in both normal and reverse directions.
  • the reverse rollers 46 are first rotated in the normal direction to direct the sheet 3 toward the reverse guide plate 48, and then rotated in the reverse direction to transport the sheet 3 in the reverse direction.
  • the re-circulation rollers 47 are positioned downstream of the reverse rollers 46 and are positioned immediately therebelow in the casing 44.
  • the re-circulation rollers 47 include a pair of rollers to direct the sheet 3 reversely driven by the reverse rollers 46 toward the re-circulation tray 43.
  • the reverse guide plate 48 is constituted by a plate like member extending upwardly from the upper end of the casing 44 for guiding travel of the sheet 3 fed by the reverse rollers 46.
  • the flapper 45 is switched to a position allowing the sheet 3 to be fed toward the reverse roller pair 46.
  • the sheet 3 whose front surface has been formed with an image is received in the sheet reverse section 42.
  • the reverse roller 46 is rotated in a normal direction for temporarily discharging the paper upwardly along the reverse guide plate 48.
  • the reverse roller pair 46 are reversely rotated to feed the sheet 3 downwardly toward the re-circulation roller pair 47.
  • a sheet sensor 56 is provided downstream of the fixing portion 19 for detecting the sheet 3.
  • a reverse timing for changing the rotating direction of the reverse roller 46 from the normal rotation to the reverse rotation is controlled such that the reverse timing occurs after elapse of a predetermined period starting from a detection timing at which the sheet sensor 56 detects a trailing edge of the sheet 3.
  • the flapper 45 is switched to its original posture, i.e., a posture allowing the sheet to be fed to the downstream feed roller 34 from the feed roller 33 upon completion of feeding of the sheet to the reverse roller 46.
  • the sheet 3 reversely fed by the re-circulation roller pair 47 is delivered to the re-circulation tray 43 by the re-circulation roller pair 47.
  • the re-circulation tray 43 has a sheet receiving portion 49, a tray 50 and diagonal feed rollers 51.
  • the sheet receiving portion 49 is externally attached to the main casing 2 at a position below the sheet reverse section 42, and has an arcuate sheet guide member 52.
  • the sheet 2 substantially vertically downwardly oriented from the re-circulation roller pair 47 can be oriented in a substantially horizontal direction along the curvature of the sheet guide member 52 toward the tray 50.
  • the tray 50 has a rectangular plate-like shape, and is oriented in a horizontal direction above the sheet tray 6. An upstream end of the tray 50 is connected to the sheet guide member 52, and a downstream end of the tray 50 is connected to a re-circulation path guide 53 provided along the sheet transport path 38 in order to guide the sheet 3 from the tray 50 to the second transport portion 10.
  • each diagonally feed roller 51 includes a diagonal feed drive roller 54 whose rotation axis extends substantially perpendicular to the sheet feeding direction, and a diagonal feed driven roller 55 in nipping relation to the drive roller 54.
  • a rotation axis of the driven roller 55 extends in a direction displacing from the direction perpendicular to the sheet feeding direction, but extends in a slanting direction for allowing the sheet to be brought into abutment with the reference plate.
  • the sheet 3 delivered from the sheet receiving portion 49 to the tray 50 moves toward the image forming section 5, with the sheet having been turned upside down, through the re-circulation path guide 53 while one widthwise edge of the sheet is in slidingly abutting relation to the reference plate by the driving of the diagonally feed rollers 51.
  • the back surface of the sheet 3 is in confrontation with the photosensitive drum 23 for transferring a toner image to the back surface from the photosensitive drum 23.
  • the toner image is then fixed at the fixing portion 19, and is then discharged onto the discharge tray 36.
  • the first and second transport portions 9 and 10 are disposed at the sheet transport path 38 for efficiently removing paper dusts spreading over the entire surface of the sheet 3 accompanied by sheet cutting for providing cut sheets or generated due to friction force occurring between the pad member 13b and the sheet supply roller 12 at the paper supply section 7.
  • the first transport portion 9 is positioned at a frontal side of the sheet transport path 38 and downstream of the sheet supply roller 12 of the sheet supply section 7 with a predetermined space therefrom. Further, the first transport portion 9 is positioned upstream of a joining portion between the sheet transport path 38 and a downstream end of the re-circulation path guide 53.
  • the first transport portion 9 includes a first transport roller 9a for transporting the sheet 3, a first paper dust removing roller 9b and positioned in opposition to the first transport roller 9a with respect to the sheet transport path 38, a first sponge member 9c serving as a first scraper disposed immediately below the first paper dust removing roller 9b, and first reverse transport preventive member 9m for preventing the paper dust from being transported from the first sponge member 9c to the sheet transport path 38.
  • the first transport roller 9a is positioned inwardly of a curvature of the sheet transport path 38, and includes a metallic roller shaft 9d and a rubber layer 9e formed thereover.
  • the roller shaft 9d is rotatably supported by the main casing 2.
  • the first transport roller 9a is drivingly rotatable in a direction indicated by an arrow,(clockwise direction in Fig. 1 ) through a power transmission from a motor (not shown). That is, a region of the first transport roller 9a confronting the sheet transport path 38 is rotated in the normal direction, i.e., in the sheet feeding direction.
  • the first paper dust removing roller 9b is disposed outwardly of the curvature of the sheet transport path 38, and includes a metallic roller shaft 9f and a rubber layer 9g having easily chargeable surface.
  • the rubber layer is made from a fluororesin, or rubber whose outer surface is formed with fluorine coating.
  • the first paper dust removing roller 9b is shown in Fig. 3(c) .
  • the first paper dust removing roller 9b is so positioned as to brought into contact with the sheet surface (to be in contact with the photosensitive drum) which has been contacted with the pad member 13b, and to align with a longitudinally center portion of the first transport roller 9a, the center portion being in confrontation with the separation pad 13.
  • the width (axial length) of the rubber layer roller 9g is smaller than a width of a roller 10g of a second paper dust removing roller 10b described later, and slightly greater than the width B of the pad member 13b as shown in Figs. 3(c) and 3(d) .
  • the main casing 2 has a support member 100a, and the first paper dust removing roller 9b has a roller, shaft 9f roatably supported by the support member 100a as shown in Fig 2 .
  • the first paper dust removing roller 9b is driven by the first transport roller 9a and rotated in a direction indicated by an arrow (counterclockwise direction in Fig. 1 ). That is, a region of the first paper dust removing roller 9b confronting the sheet transport path 38 is rotated in the normal direction, i.e., in the sheet feeding direction.
  • the first transport roller 9a and the first paper dust removing roller 9b nip the sheet 3 therebetween for transporting the sheet 3 while removing the paper dusts from the sheet 3.
  • the first transport roller 9a and the first paper dust removing roller 9b can be reversely rotated for removing a jamming sheet.
  • the first sponge member 9c is formed from a material which can easily charge the first paper dust removing roller 9b. Typical material is urethane foam.
  • the first sponge member 9c is positioned immediately below the first paper dust removing roller 9b and in pressure contact therewith at a position opposite to the sheet transport path 38 with respect to the paper dust removing roller 9b so as to scrape off the paper dust from the paper dust removing roller 9b.
  • the first sponge member 9c is in sliding contact with the first paper dust removing roller 9b to frictionally charge the surface of the first paper dust removing roller 9b.
  • a width of the first sponge member 9c is slightly greater than the width of the roller 9g of the first paper dust removing roller 9b as shown in Fig. 3(c) .
  • the first reverse transportation preventive member 9m is disposed downstream of a contacting position between the first paper dust removing roller 9b and the sheet 3 in the normal rotating direction of the roller 9b, and upstream of a contacting position between the first paper dust removing roller 9b and the first sponge member 9c in the normal rotating direction of the roller 9b.
  • The'first reverse transportation preventive member 9m extends in parallel with the axial direction of the first paper dust removing roller 9b and confronts the roller 9b with a predetermined space.
  • the first reverse transportation preventive member 9m is L-shape in cross-section having a base portion 9n and a tip portion 9p bent from the base portion 9n.
  • the first reverse transportation preventive member 9m is provided integrally with the support member 100a of the main casing 2 as a part of the support member. As shown in Fig. 6 , a width of the first reverse transportation preventive member 9m is greater than the widths of the first paper dust removing roller 9b and the first sponge member 9c.
  • the base portion 9n is positioned opposite to the sheet transport path 38 with respect to the first paper dust removing roller 9b and slantingly extends in generally vertical direction and spaced away from the first paper dust removing roller 9b.
  • the tip portion 9p is bent from an upper end of the base portion 9n at an acute angle toward the first paper dust removing roller 9b.
  • a gap L between a tip end 9t of the tip portion 9p and the outer peripheral surface of the first paper dust removing roller 9b is in a range of from 0.2 to 2.0 mm, preferably, 0.5 to 2.0 mm.
  • this gap L permits the paper dusts (about several ⁇ mm in size) adhered onto the first paper dust removing roller 9b during its normal rotation to pass through the gap toward the first sponge member 9c, but prevents a lump of paper dusts (about several mm in size) scrapped off by the first sponge member 9c and then released therefrom from passing through the gap toward the sheet transport path 38 during reverse rotation of the first paper dust removing roller 9b.
  • the first reverse transportation preventive member 9m is designed to provide an angle ⁇ at an intersection between lines Y and Z not more than 90 degrees, in which the line Y is a tangential line with respect to a line X connecting between the tip end 9t of the tip end portion 9p and a rotational center of the first paper dust removing roller 9b, and the line Z is the extending direction of the tip end portion 9p. Further, the tip end portion 9p is positioned upstream of the line X in the normal rotating direction of the first paper dust removing roller 9b. With this arrangement, the tip end 9t can confront with and contact with the paper dusts adhered onto the first paper dust removing roller 9b from the first sponge member 9c during reverse rotation (clockwise rotation in Fig. 4 ) of the first paper dust removing roller 9b.
  • the second transport portion 10 is positioned above and downstream of the first transport portion 9. Further, the second transport portion 10 is positioned downstream of the joining portion between the sheet transport path 38 and the downstream end of the re-circulation path guide 53.
  • the second transport portion 10 includes a second transport roller 10a for transporting the sheet 3, a second paper dust removing roller 10b positioned in opposition to the second transport roller 10a with respect to the sheet transport path 38, a second sponge member 10c serving as a scraper disposed immediately below the second paper dust removing roller 10b, and a second reverse transportation preventive member 10m for preventing the paper dust from being transported from the second sponge member 10c to the sheet transport path 38.
  • the second transfer roller 10a is positioned inwardly of the curvature of the sheet transport path 38, and includes a metallic roller shaft 10d and a rubber layer 10e formed thereover.
  • the roller shaft 10d is rotatably supported by the main casing 2.
  • the second ransport roller 10a is drivingly rotatable in a direction indicated by an arrow, (clockwise direction in Fig. 1 ) through a power transmission from the motor (not shown). That is, a region of the second transport roller 10a confronting the sheet transport path 38 is rotated in the normal direction, i.e., in the sheet feeding direction.
  • the second paper dust removing roller 10b is disposed outwardly of the curvature of the sheet transport path 38, and includes a metallic roller shaft 10f and a rubber layer 10g having easily chargeable surface.
  • the rubber layer is made from a fluororesin, or rubber whose outer surface is formed with fluorine coating.
  • the second paper dust removing roller 10b is so positioned as to brought into contact with an entire sheet surface (to be in contact with the photosensitive drum 23) which has been contacted with the pad member 13b.
  • a width (axial length) of the rubber layer roller 10g is slightly greater than the sheet width A as shown in Fig. 3(b) .
  • the main casing 2 has a second support member 100b, and the roller shaft 10f of the second paper dust removing roller 10b is rotatably supported by the support member 100b.
  • the second paper dust removing roller 10b is positively driven upon power input from a motor (not shown), so that the second paper dust removing roller 10b is rotatable in a normal direction indicated by an arrow in Fig. 2 , that is, in the sheet feeding direction (counter clockwise direction in Fig. 1 ) at a region facing with the sheet transport path 38.
  • the sheet 3 is nipped between the second transport roller 10a and the second paper dust removing roller 10b for feeding, while the paper dust is removed by the second paper dust removing roller 10b.
  • the second transport roller 10a and second paper dust removing roller 10b are reversely rotatable for removing jamming sheet described later.
  • the second sponge member 10c is formed from a material which can easily charge the second paper dust removing roller 10b. Typical material is urethane foam.
  • the second sponge member 10c is positioned immediately below the second paper dust removing roller 10b and in pressure contact therewith at a position opposite to the sheet transport path 38 with respect to the paper dust removing roller 10b so as to scrape off the paper dust from the paper dust removing roller 10b.
  • the second sponge member 10c is in sliding contact with the second paper dust removing roller 10b to frictionally charge the surface of the roller 10g of the second paper dust removing roller 10b.
  • a width of the second sponge member 10c is slightly greater than the width (axial length) of the second paper dust removing roller 10b as shown in Fig. 3(b) .
  • the second reverse transportation preventive member 10m is disposed downstream of a contacting position between the second paper dust removing roller 10b and the sheet 3 in the normal rotating direction of the roller 10b, and upstream of a contacting position between the second paper dust removing roller 10b and the second sponge member 10c in the normal rotating direction of the roller 10b.
  • the second reverse transportation preventive member 10m extends in parallel with the axial direction of the second paper dust removing roller 10b and confronts the roller 10b with a predetermined space.
  • the second reverse transportation preventive member 10m is L-shape in cross-section having a base portion 10n and a tip portion 10p bent from the base portion 10n.
  • the second reverse transportation preventive member 10m is provided integrally with the support member 100b as a part of the support member 100b. As shown in Fig. 3(b) , a width of the second reverse transportation preventive member 10m is greater than the widths of the second paper dust removing roller 10b and the second sponge member 10c.
  • the base portion 10n is positioned opposite to the sheet transport path 38 with respect to the second paper dust removing roller 10b and slantingly extends in generally vertical direction and spaced away from the second paper dust removing roller 10b.
  • the tip portion 10p is bent from a lower end of the base portion 10n at an acute angle toward the second paper dust removing roller 10b.
  • a gap between a tip end of the tip portion 10p and an outer peripheral surface of the second paper dust removing roller 10b is in a range of from 0.2 to 2.0 mm, preferably, 0.5 to 2.0 mm.
  • this gap permits the paper dusts (about several ⁇ mm in size) adhered onto the second paper dust removing roller 10b during its normal rotation to pass through the gap toward the second sponge member 10c, but prevents a lump of paper dusts (about several mm in size) scrapped off by the second sponge member 10c from passing through the gap toward the sheet transport path 38 during reverse rotation of the second paper dust removing roller 10b.
  • the second reverse transportation preventive member 10m is designed to provide an angle at an intersection between a tangential line with respect to a line connecting between the tip end of the tip end portion 10p and a rotational center of the second paper dust removing roller 10b and an extension line of the tip end portion 10p as being not more than 90 degrees. Further, the tip end portion 10p is positioned upstream of the line connecting between the tip end of the tip end portion 10p and the rotational center of the second paper dust removing roller 10b in the normal rotating direction of the second paper dust removing roller 10b. With this arrangement, the tip end of the second reverse transportation preventive member 10m can confront with and contact with the paper dusts adhered onto the second paper dust removing roller 10b from the second sponge member 10c during reverse rotation of the second paper dust removing roller 10b.
  • the sheet 3 stacked on the sheet supply tray 6 is separated from the sheet stack and supplied in cooperation with the sheet supply roller 12 and the separation pad 13. During this sheet supply, a large amount of paper dusts are generated at the image forming surface of the sheet due to the friction against the separation pad 13. However, when the sheet 3 is transported to the first transport portion 9 and the sheet 3 is nipped between the first transport roller 9a and the first paper dust removing roller 9b, the image forming surface is in brought into contact with the roller 9g of the first paper dust removing roller 9b.
  • the width of the first paper dust removing roller 9b is greater than that of the separation pad 13, the paper dusts spreading in a width substantially equal to the width of the pad member 13b is scraped off by the roller 9g of the first paper dust removing roller 9b and are electrostatically absorbed thereon.
  • the paper dusts transferred onto the roller 9g of the first paper dust removing roller 9b is then scraped off therefrom by the first sponge member 9c by the normal rotation of the first paper dust removing roller 9b, after the paper dusts passes through the gap L between the first reverse transportation preventive member 9m and the first paper dust removing roller 9b.
  • the image forming surface is in brought into contact with the roller 10g of the second paper dust removing roller 10b. Because the width of the second paper dust removing roller 10b is greater than the sheet width, the paper dusts having been generated at the sheet cutting and spreading over entire width of the sheet as well as residual paper dusts which have not been completely removed by the first paper dust removing roller 9b can be scraped off by the roller 10g of the second paper dust removing roller 10b and are electrostatically absorbed thereon.
  • the paper dusts transferred onto the roller 10g of the second paper dust removing roller 10b is then scraped off therefrom by the second sponge member 10c through the normal rotation of the second paper dust removing roller 10b, after the paper dusts passes through the gap between the second reverse transportation preventive member 10m and the second paper dust removing roller 10b.
  • the paper dusts removed by the first and second transport portions 9, 10 are scraped by the first and second sponge members 9c, 10c, and accumulated thereon to become paper dust lumps, which are then fallen down onto a receiving surface 65 described later.
  • the sheet 3 supplied by the sheet supply section 7 is first subjected to paper dust removal by the first paper dust removing roller 9b, the dust being generated in greater amount due to the friction against the pad member 13b, and then, subjected to paper dust removal by the second paper dust removing roller 10b, the dust having being inherently spreading in a lesser amount over the entire surface of the sheet due to paper cutting. Accordingly, efficient paper dust removal in accordance with the amount of paper dust can be performed, thereby achieving uniform paper dust removal.
  • the width of the second paper dust removing roller 10b is greater than the sheet width whereas the width of the first paper dust removing roller 9b is greater than that of the separation pad 13 and smaller than,the width of the second paper dust removing roller 10b, the first paper dust removing roller 9b does not necessarily has a longer width but has an optimum width yet performing sufficient paper dust removal. Thus, production cost can be lowered.
  • the first paper dust removing roller 9b is spaced away from and downstream of the sheet supply roller 12 by a predetermined space to avoid direct contact therewith. Assuming that the first paper dust removing roller 9b is in direct contact with the sheet supply roller 12. If a subsequent sheet 3 is slightly pulled out and follows a precedent sheet 3 in partly overlapping relation with the precedent sheet due to the frictionally sliding relationship between the sheet supply roller 12 and the separation pad 13, operation of the laser printer 1 may be stopped while the leading end portion of the subsequent sheet is nipped between the sheet supply roller 12 and the first paper dust removing roller 9b. Therefore, the nipped leading end portion of the subsequent sheet may be shaped into a curl. Therefore, sheet jamming may occur due to the subsequent feeding of the curly sheet, or image distortion may occur at the curled portion.
  • the first sponge member 9c is provided in confrontation with the first paper dust removing roller 9b to scrape off the paper dust adhered to the first paper dust removing roller 9b
  • the second sponge member 10c is provided in confrontation with the second paper dust removing roller 10b to scrape off the paper dust adhered to the second paper dust removing roller 10b.
  • first and second sponge members 9c and 10c is slightly greater than the width of the associating first and second paper dust removing rollers 9b and 10b, respectively, paper dust can be desirably scraped off even if a paper dust area slightly exceeds from the width of the paper dust removing rollers due to the pressure contact between the sheet and the paper dust removing rollers.
  • the sheet 3 supplied by the sheet supply section 7 is first delivered by the first transport roller 9a and the first paper dust removing rollers 9b while the paper dusts are removed, and is then delivered by the second transport roller 10a and the second paper dust removing rollers 10b while the paper dusts are again removed. Therefore, desirable sheet transportation to the image forming section 5 results while performing efficient paper dust removal.
  • the second paper dust removing roller 10b is not slave-driven by the second transport roller 10a but the second paper dust removing roller 10b is a self-driving component, because it is supplied with driving power from the motor (not shown). Therefore, constant rotation of the second paper dust removing roller 10b can result to perform effective paper dust removal and effective sheet feeding, even if a resistive load is applied to the entirety of the roller portion 10g of the second paper dust removing roller 10b due to the contact with the sheet 3 and the second sponge member 10c.
  • the re-circulation unit 41 is provided, and the first transport portion 9 is disposed upstream of the joint portion between the sheet transport path 38 and the re-circulation path guide 53, whereas the second transport portion 10 is disposed downstream of the joint portion.
  • the first paper dust removing roller 9b is disposed upstream of the joint portion, the first paper dust removing roller 9b is exclusively in contact with the sheet 3 supplied from the sheet supply section 7.
  • the second paper dust removing roller 10b is disposed downstream of the joint portion, the second paper dust removing roller 10b is in contact with the sheet supplied from the sheet supply section 7 and the sheet supplied from the re-circulation path guide 53.
  • the first paper dust removing roller 9b removes the greater amount of paper dusts generated due to the friction against the pad member 13b with respect to the sheet supplied from the sheet supply section 7, whereas the second paper dust removing roller 10b removes the paper dust on the sheet which has been subjected to paper dust removal by the first paper dust removing roller 9b and which has been fed from the sheet supply section 7, and also removes the paper dust on the sheet fed from the re-circulation path guide 53.
  • the sheet fed from the re-circulation path guide 53 one image forming surface which has been in contact with the roller portion 9g of the first paper dust removing roller 9b is not in confrontation with the second paper dust removing roller 10b, but an opposite surface of the sheet is in contact therewith. Because the opposite surface of the sheet does not carry the paper dusts caused by the friction against the pad member 13b. Accordingly, the second paper, dust removing roller 10b can only remove the lesser amount of paper dusts caused by paper cutting over the entire surface of the sheet.
  • the feeder portion 4 of the laser printer 1 also includes a multiple purpose tray 14 for stacking thereon a stack of a random size sheets 3, a multiple purpose sheet supply mechanism 15 for supplying the sheet on the multiple purpose tray 14, and a multiple purpose sheet transport portion 16.
  • the multiple purpose sheet supply mechanism 15 includes a multiple purpose sheet supply roller 15a and a multiple purpose separation pad 15b positioned in direct confrontation with the multiple purpose sheet supply roller 15a.
  • the multiple purpose separation pad 15b includes a support frame 15c, a multiple purpose pad member 15d and a spring 15e.
  • the support frame 15c has a base end portion pivotally supported to the main casing 2 and having an L-shape cross-section, and a free end portion integral with the base end portion and in confrontation with and below the multiple purpose sheet supply roller 15a.
  • the free end portion is embedded with the multiple purpose pad member 15d, and the spring 15e is seated on the other side of the pad member 15d for normally urging the multiple purpose pad member 15d toward the sheet supply roller 15a.
  • the multiple purpose pad member 15d has a generally rectangular plate shape and is made from an elastic material such as polyurethane rubber.
  • a width of the multiple purpose separation pad 15b has such width as to contact with a widthwise center portion of the sheet for the sheet feeding.
  • the multiple purpose transport portion 16 is positioned above the second transport portion 10, downstream of the multiple purpose sheet supply mechanism 15 and upstream of the register roller 11 disposed at a sheet transport path 38a between the multiple purpose sheet supply mechanism 15 and the image forming section 5.
  • the multiple purpose transport portion 16 includes a multiple purpose transport roller 16a for transporting the sheet 3, a multiple purpose paper dust removing roller 16b in confrontation therewith, a multiple purpose sponge member 16c as a scraping member immediately below the multiple purpose paper dust removing roller 16b, and a multiple purpose reverse transportation preventive member 16m for preventing the paper dusts released from the multiple purpose sponge member 16c from being transported, into the sheet transport path 38a.
  • the multiple purpose transport roller 16a includes a metallic roller shaft 16d and a rubber layer 16e formed thereover.
  • the roller shaft 16d is rotatably supported by the main casing 2, and is drivingly rotatable in a direction indicated by an arrow in Fig. 2 (counterclockwise direction in Fig. 1 ) through a power transmission from a motor (not shown). That is, the region of the roller 16a in confrontation with the sheet transport path 38a is drivingly rotated in the normal direction the same as the sheet feeding direction.
  • the multiple purpose paper dust removing roller 16b includes a metallic roller shaft 16f and a rubber layer 16g having easily chargeable surface.
  • the rubber layer is made from a fluororesin, or rubber whose outer surface is formed with fluorine coating.
  • the multiple paper dust removing roller 6b is so positioned as to brought into contact with the sheet surface which has been contacted with the multiple purpose pad member 15d, and to align with a center portion of the multiple purpose transport roller 16a, the center portion being in confrontation with the multiple purpose separation pad 15b.
  • the width (axial length) of the multiple purpose rubber layer roller 16g is slightly greater than a width of the multiple purpose pad member 15d.
  • the main casing 2 has a support member 100c, and the roller shaft 16f of the multiple purpose paper dust removing roller 16b is rotatably supported by the support member 100c.
  • the multiple purpose paper dust removing roller 16b is driven by the multiple purpose transport roller 16a, and is rotated in a direction indicated by an arrow (clockwise direction) in Fig. 2 , that is, in the sheet feeding direction at a region facing with the sheet transport path 38a.
  • the sheet 3 is nipped between the multiple purpose transport roller 16a and the multiple purpose paper dust removing roller 16b for feeding, while the paper dust is removed by the multiple purpose paper dust removing roller 16b.
  • the multiple purpose transport roller 16a and the multiple purpose paper dust removing roller 16b are reversely rotatable for removing jamming sheet.
  • the multiple purpose sponge member 16c is formed from a material which can easily charge the multiple purpose paper dust removing roller 16b. Typical material is urethane foam.
  • the multiple purpose sponge member 16c is positioned immediately below the multiple purpose paper dust removing roller 16b and in pressure contact therewith at a position opposite to the sheet transport path 38a extending from the multiple purpose sheet supply mechanism 15 with respect to the paper dust removing roller 16b so as to scrape off the paper dust from the paper dust removing roller 16b.
  • a width of the multiple purpose sponge member 16c is slightly greater than the width of the roller 16g of the multiple purpose paper dust removing roller 16b.
  • the multiple purpose sponge member 16c is in sliding contact with the multiple purpose paper dust removing roller 16b to frictionally charge the surface of the roller portion 16g of the multiple purpose paper dust removing roller 16b.
  • the multiple purpose reverse transportation preventive member 16m is disposed downstream of a contacting position between the multiple purpose paper dust removing roller 16b and the sheet 3 in the normal rotating direction of the roller 16b, and upstream of a contacting position between the multiple purpose paper dust removing roller 16b and the multiple purpose sponge member 16c in the normal rotating direction of the roller 16b.
  • the multiple purpose reverse transportation preventive member 16m extends in parallel with the axial direction of the multiple purpose paper dust removing roller 16b and confronts the roller 16b with a predetermined space.
  • the multiple purpose reverse transportation preventive member 16m is L-shape in cross-section having a base portion 16n and a tip portion 16p bent from the base portion 16n.
  • the multiple purpose reverse transportation preventive member 16m is provided integrally with the support member 100c of the main casing 2 as a part of the support member 100c.
  • a width of the multiple purpose reverse transportation preventive member 16m is greater than the widths of the multiple purpose paper dust removing roller 16b and the multiple purpose sponge member 16c.
  • the base portion 16n is positioned opposite to the sheet transport path 38a with respect to the multiple purpose paper dust removing roller 16b and therebelow, and slantingly extends in generally vertical direction and spaced away from the multiple purpose paper dust removing roller 16b.
  • the tip portion 16p is bent from an upper end of the base portion 16n at an acute angle toward the multiple purpose paper dust removing roller 16b.
  • a gap between a tip end of the tip portion 16p and the multiple purpose paper dust removing roller 16b is in a range of from 0.2 to 2.0 mm, preferably, 0.5 to 2.0 mm.
  • this gap permits the paper dusts (about several ⁇ mm in size) adhered onto the multiple purpose paper dust removing roller 16b during its normal rotation to pass through the gap toward the multiple purpose sponge member 16c, but prevents a lump of paper dusts (about several mm in size) scrapped off by the multiple purpose sponge member 16c and released therefrom from passing through the gap toward the sheet transport path 38a during reverse rotation of the multiple purpose paper dust removing roller 16b.
  • the multiple purpose reverse transportation preventive member 16m is designed to provide an angle at an intersection between a tangential line with respect ,to a line connecting between the tip end of the tip end portion 16p and a rotational center of the multiple purpose paper dust removing roller 16b and an extension line of the tip end portion 16p as being not more than 90 degrees. Further, the tip end portion 16p is positioned upstream of the line connecting between the tip end of the tip end portion 16p and the rotational center of the multiple purpose paper dust removing roller 16b in the normal rotating direction of the multiple purpose paper dust removing roller 16b.
  • the tip end of the multiple purpose reverse transportation preventive member 16m can confront with and contact with the paper dusts adhered onto the multiple purpose paper dust removing roller 16b from the multiple purpose sponge member 16c during reverse rotation of the multiple purpose paper dust removing roller 16b.
  • the sheet 3 stacked on the multiple purpose sheet supply tray 14 in the multiple purpose sheet supply mechanism 15 is separated from the sheet stack and supplied in cooperation with the multiple purpose sheet supply roller 15a and the multiple purpose separation pad 15b. During this sheet supply, a large amount of paper dusts are generated at the surface of the sheet due to the friction against the multiple purpose separation pad 15b.
  • the paper dusts generated upon friction against the multiple purpose separation pad 15b and spreading in a width substantially equal to the width of the multiple purpose pad member 15d is scraped off by the roller 16g of the multiple purpose paper dust removing roller 16b and are electrostatically absorbed thereon, because the width of the multiple purpose paper dust removing roller 16b is slightly greater than that of the multiple purpose separation pad 15b.
  • the paper dusts transferred onto the roller 16g of the multiple purpose paper dust removing roller 16b is then scraped off therefrom by the multiple purpose sponge member 16c by the rotation of the multiple purpose paper dust removing roller 16b in the direction of arrow (clockwise direction in Fig. 2 ) after the paper dusts pass through the gap between the multiple purpose reverse transportation preventive member 16m and the multiple purpose paper dust removing roller 16b.
  • paper dust generated upon friction against the multiple purpose separation pad 15b and spreading over the width of the multiple purpose separation pad 15b can be desirably removed off from the surface of the sheet 3.
  • the paper dusts will become a paper dust lump after scraped off from multiple purpose paper dust removing roller 16b by the multiple purpose sponge member 16c and being deposited thereon, and then the paper dust lump will be falling down onto the receiving surface 65 as described later.
  • the jammed sheet can be pulled out from the sheet supply section 7, i.e., from the lower side of the first transport portion 9 after pulling out the sheet supply tray 6.
  • the first paper dust removing roller 9b and the second paper dust removing roller 10b those in contact with the sheet 3 are reversely rotated, which causes the paper dust lumps scraped by and accumulated on the first and second sponge members 9c and 10c to be transported back toward the first paper dust removing roller 9b and the second paper dust removing roller 10b.
  • the paper dust lumps cannot pass through the gap L between the tip end 9t of the first reverse transportation preventive member 9m and the first paper dust removing roller 9b nor through the gap between the second reverse transportation preventive member 10m and the second paper dust removing roller 10b when the lumps are brought into confrontation with the tip end portions of the first and second reverse transportation preventive members 9m, 10m, respectively.
  • the lumps are dammed at the tip end portions 9p, 10p of the first and second reverse transportation preventive member 9m, 10m, respectively. Therefore, these lumps cannot be introduced into the sheet transport path 38.
  • the jammed sheet can be pulled out from the sheet supply section, i.e., from the multiple purpose supply tray 14.
  • the multiple purpose paper dust removing roller 16b in contact with the sheet 3 is reversely rotated, which causes the paper dust lumps scraped by and accumulated on the multiple purpose sponge member 16c to be transported back in accordance with the reverse rotation of the multiple purpose paper dust removing roller 16b.
  • the paper dust lump cannot pass through the gap between the multiple purpose reverse transportation preventive member 16m and the multiple purpose paper dust removing roller 16b when the lump is brought into confrontation with the tip end portion 16p of the multiple purpose reverse transportation preventive member 16m.
  • the lump is dammed at the tip end portion 16p of the multiple purpose reverse transportation preventive member 16m. Therefore, the lump cannot be introduced into the sheet transport path 38a.
  • the respective gaps allow the paper dusts to pass therethrough toward the first sponge member 9c, the second sponge member 10c and the multiple purpose sponge member 16c, respectively, during normal rotations of the first paper dust, removing roller 9b, the second paper dust removing roller 10b and the multiple purpose paper dust removing roller 16b, but the gaps prevent the paper dusts from passing therethrough in the reverse direction during reverse rotations of the first paper dust removing roller 9b, the second paper dust removing roller 10b and the multiple purpose paper dust removing roller 16b.
  • paper dusts adhered onto the rollers 9b, 10b, 16b can surely be transported to the sponge members 9c, 10c, 16c, and reversal transportation of the paper dusts from the sponge members 9c, 10c, 16c to the transport paths 38, 38a can be prevented.
  • the tip end portions 9p, 10p and 16p of the first reverse transportation preventive member 9m, second reverse transportation preventive member 10m and multiple purpose reverse transportation preventive member 16m can confront and contact with the paper dust lumps transported back in accordance with the reverse rotations of these rollers 9b, 10b, 16b. Therefore, the paper dust lumps cannot be transported back any more.
  • the first reverse transportation preventive member 9m, second reverse transportation preventive member 10m and multiple purpose reverse transportation preventive member 16m can prevent reversal transportation of the paper ust lumps.
  • the paper dust lumps can surely be blocked by the first reverse transportation preventive member 9m, second reverse transportation preventive member 10m and multiple purpose reverse transportation preventive member 16m, even if the paper dust lumps are spreading over the entire width of the sponge members 9c, 10c, 16c, and these paper dust lumps are transferred toward the rollers 9b, 10b, 16b over their entire widths.
  • first reverse transportation preventive member 9m, second reverse transportation preventive member 10m, and multiple purpose reverse transportation preventive member 16m are not separate members but provided integrally with the support members 100a, 100b, 100c of the main casing 2, respectively. Therefore, the first reverse transportation preventive member 9m, second reverse transportation preventive member 10m, and multiple purpose reverse transportation preventive member 16m can be easily formed to reduce the number of mechanical components, to thus lower the production cost.
  • the base portion 9n and the tip end portion 9p are flat plate shapes, and the base end portion 9n and the tip end portion 9p are formed by bending at an acute angle at a proper portion.
  • a tip end portion 9p' is an extension of a curved portion instead of the acute angled bent portion.
  • a tip end face 9t' is directed to confront against the reversal rotation of the first paper dust removing roller 9b, and the tip end portion 9p' is intersected with the tangential line at an angle not more than 90 degrees, and further, the tip end portion 9b is disposed upstream of the line X connecting between the tip end face 9t' and the rotational center of the first paper dust removing roller 9b in the normal rotating direction thereof.
  • the paper dusts scraped by the first sponge member 9c, the second sponge member 10c, and the multiple purpose sponge member 15c are dropped down from each sponge due to gravity when the scraped paper dust has become a mass or lump of a predetermined size.
  • a paper dust chute 39 for guiding downward travel of the paper dust mass.
  • the paper dust chute 39 vertically extends in front of the sheet transport path 38 and is constituted by a guide plate section 61, an extension section 62 and a partition plate 63.
  • the guide plate 61 is a thin plate like member constituting a front side of the sheet transport path 38 so as to guide the sheet 3 from the sheet supply section 7 to the image forming section 5.
  • the guide plate 61 has one side serving as the sheet transport path 38, and another side serving as the paper dust chute. More specifically, the guide plate 61 includes a first guide plate 61a for directing the sheet 3 from the second transport portion 10 to the register roller 11, and a second guide plate 61b for directing the sheet 3 from the first transport portion 9 to the second transport portion 10.
  • the first guide plate 61a is a thin plate member slantingly extending from an upper space of the second transport portion 10 to the front of the register roller 11.
  • the first guide plate 61a has one side face guiding the travel of the sheet 3 from the second transport portion 10 to the register roller 11. Another side face of the first guide plate 61a allows the paper dust falling from the multiple purpose transport portion 16 positioned above the first guide plate 61a to direct downwardly.
  • the first guide plate 61a has a lower end integrally provided with an extension portion 62a slantingly extending downwardly for covering an upper portion of the second transport portion 10.
  • the second guide plate 61b is a thin plate member and is moderately curved in S-shape from the lower space of the second transport portion 10 to the lower space of the first transport portion 9.
  • the second guide plate 61b has one side face guiding the travel of the sheet 3 from the first transport portion 9 to the second transport portion 10. Another side face of the second guide plate 61b allows the paper dust falling from the second transport portion 10 positioned above the second guide plate 61b to direct downwardly as well as the paper dust falling from the multiple purpose transport portion 16.
  • the second guide plate 61b has an intermediate portion provided with a thin plate-like extension portion 62b slantingly extending downwardly for covering an upper portion of the first transport portion 9.
  • base end portions 9n, 10n of the first and second reverse transportation preventive member 9m, 10m also serve as guide members for guiding downward travel of the falling paper dusts.
  • a third guide plate 61c is formed continuously from the second guide plate 61b at a position lower than the confronting position between the first paper dust removing roller 9b and the first sponge member 9c.
  • the third guide plate 61c has a lower end portion bent horizontally at a position above the attachment/detachment path of the sheet supply tray 6.
  • the partition plate 63 is positioned in front of the second guide plate 61b with a predetermined space therefrom.
  • the partition plate 63 includes a side plate 63c extending in a vertical direction and a bottom plate 63d bent at substantially right angle from a lower end of the side plate 63c toward frontward.
  • a front side bottom wall 64 is provided in front of and below the first paper dust removing roller 9b and first sponge member 9c.
  • the front side bottom wall 64 positioned above and extends in parallel with the attachment/detachment path of the sheet supply tray 6, and has a front end portion contiguous with a front wall of the main casing 2, and a rear end portion serving as the receiving surface 65 for receiving thereon the paper dusts falling down from the multiple purpose transport portion 16, the second transport portion 10, and the first transport portion 9.
  • the receiving surface 65 includes a recessed portion 66, a slant wall portion 67 and a ridge portion 68.
  • the recessed portion 66 has a semi-circular cross-section and is positioned opposite to the sheet transport path 38 with respect to the first paper dust removing roller 9b and the first sponge member 9c, and extends in the axial direction of the first paper dust removing roller 9b.
  • the slant wall portion 67 is positioned closer to the sheet transport path 38 than the recessed portion 66 to the sheet transport path 38, and is slanted upwardly toward the sheet transport path 38.
  • the ridge portion 68 is positioned opposite to the first paper dust removing roller 9b and first sponge member 9c with respect to the recessed portion 66, and has a height lower than the upper end portion of the slant wall portion 67.
  • an auger member (spiral feed member) 71 as paper dust transport unit described later is provided at a space of the recessed portion 66.
  • the paper dust scraped by the multiple purpose sponge member 16c in the multiple purpose transport portion 16 and becoming paper dust lumps are guided along the first guide plate 61a and dropped onto the extension portion 62a, and also guided along the base end portion 10n of the second reverse transportation preventive member 10m. Then, the paper dusts are further guided along the second guide plate 61b and dropped onto the extension portion 62b, and then guided along the base end portion 9n of the first reverse transportation preventive member 9m, and then dropped onto the receiving surface 65.
  • the paper dusts scraped by the second sponge member 10c in the second transport portion 10 and becoming the lumps are guided along the second guide plate 61b and dropped onto the extension portion 62b, and then guided along the base end portion 9n of the first reverse transportation preventive member 9m. Then, the paper dusts are dropped onto the receiving surface 65. The paper dusts scraped by the first sponge member 9c and becoming the lumps are dropped onto the receiving surface 65.
  • the base end portions 9n, 10n of the first and second reverse transportation preventive members 9m, 10m also serve as guide members for guiding downward travel of the paper dusts. Therefore, additional guide members are not required at side areas of the first and second paper dust removing rollers 9b, 10b. Accordingly, simple construction results with reducing mechanical components, to thus lower the production cost.
  • the laser printer 1 provides, as shown in Figs. 6 and 7 , the auger member 71 for transporting the paper dusts falling on the receiving surface 65 from a paper dust falling down area 83 to paper dust accumulating portions 84 those described later.
  • the auger member 71 is disposed along the recessed portion 66 of the receiving surface 65. As shown in Figs. 6 and 7 , the auger member 71 includes a shaft member 72, a first spiral portion 73 and a second spiral portion 74 integrally mounted over the shaft member 72. Spiral direction of the second spiral portion 74 is opposite to that of the first spiral portion 73. An auger drive gear 75 is mounted on one end of the shaft member 72 and beside the second spiral portion 74 for drivingly rotating the auger member 71 through a gear train 90 described later connected to a motor (not shown).
  • the gear train 90 includes a motor coupling gear 91, an upper gear train 92 for transmitting power from the motor coupling gear 91 to the multiple purpose sheet supply mechanism 15 for driving the same, and a lower gear train 93 for transmitting power from the motor coupling gear 91 to the auger member 71 for drivingly rotating the same.
  • the motor coupling gear 91 is a two sage gear including a large diameter gear in meshing engagement with the upper gear train 92 and a small diameter gear in meshing engagement with the lower gear train 93.
  • the upper gear train 92 includes three transmission gears 94, 95, 96 arrayed in a vertical direction.
  • a multiple purpose sheet supply roller drive gear 97 is fixedly mounted on one end of the roller shaft of the multiple purpose sheet supply roller 15a.
  • the transmission gear 96 is meshedly engaged with the multiple purpose sheet supply roller drive gear 97, so that the latter is rotatable in the counterclockwise direction by the rotation of the large diameter gear of the motor coupling gear 91 through the transmission gears 94, 95, 96.
  • the lower gear train 93 includes two transmission gears 98,99 arrayed in the vertical direction.
  • the transmission gear 99 is meshedly engaged with the auger drive gear 75, so that the shaft member 72 of the auger member 71 is rotatable in a clockwise direction by the rotation of the small diameter gear of the motor coupling gear 91 through the transmission gears 98, 99.
  • the auger member 71 is rotated such that the its surface moves downwardly at a side in confrontation with the slant wall portion 67 on the receiving surface 65 and moves upwardly at a side in confrontation with the ridge portion 68.
  • the first spiral portion 73 is disposed at axially half length of the shaft member 72 and is adapted for transporting the paper dusts toward one axial end of first paper dust removing roller 9b (X direction in Fig. 6 ) upon rotation of the shaft member 72.
  • the second spiral portion 74 is disposed at axially remaining half length of the shaft member 72 and is adapted for transporting the paper dusts toward other axial end of first paper dust removing roller 9b (Y direction in Fig. 6 ) upon rotation of the shaft member 72.
  • the auger member 71 can transport the paper dusts in opposite directions simultaneously toward both axial ends.
  • the paper dusts falling from the first transport portion 9, the second transport portion 10 and multiple purpose transport portion 16 can be transported toward both ends of the auger member 71 by the rotation thereof.
  • the thus distributed paper dusts into two directions can be accumulated in the paper dust accumulators 84 described later.
  • rotation speed of the first paper dust removing roller 9b is set to about 180 r.p.m.
  • rotation speed of the auger member 71 is lower than that of the first paper dust removing roller 9b such as about 60 r.p.m.
  • the laser printer 1 is provided with a regulation wall 76 at a part of and along the auger member 71.
  • the regulation wall 76 includes a first partition wall and a second partition wall.
  • the first partition wall includes one side first partition wall 77 disposed across the first spiral portion 73 in a direction perpendicular to the axial direction of the auger member 71, and another side first partition wall 78 disposed across the second spiral portion 74 in a direction perpendicular to the axial direction of the auger member 71.
  • the second partition wall 79 extends in parallel with the auger member 71 with a predetermined space therefrom.
  • One end of the second partition wall 79 is joined to the front end of the one side partition wall 77 and another end of the second partition wall 79 is joined to the front end of the other side partition wall 78, so that the regulation wall 76 is in a U-shape in a plan view.
  • the first partition walls 77, 78 have generally rectangular shape, and have widths in a direction perpendicular to the axial direction of the auger member 71 approximately the same as the width of the receiving surface 65. Lower ends of the first partition walls 77,78 are positioned lower than the contacting region between the first paper dust removing roller 9b and the first sponge member 9c, and are spaced away from an upper portion of the auger member 71 by a predetermined space. Upper ends of the first partition walls 77,78 are positioned upper than the contact region between the first paper dust removing roller 9b and the first sponge member 9c, and extend to a lid member 85 described later. The first partition walls 77, 78 are disposed in confronting relation and outwardly of the axial ends of the first paper dust removing roller 9b and the first sponge member 9c.
  • the second partition wall 79 includes a central wall 80 extending in parallel with the auger member 71 with a predetermined space therefrom, a one side slant wall 81,extending from and bent at one end of the central wall 80 toward the auger member 71, and another side slant wall 82 extending from and bent at another end of the central wall 80 toward the auger member 71.
  • the central wall 80 and the slant walls 81, 82 are provided integrally with each other.
  • the one side slant wall 81 extends between the one end of the central wall 80 and the front end of the one side first partition wall 77, and is continuous with the central wall 80.
  • the one side slant wall 81 provides a gradually narrowing space between the one side slant wall 81 and the auger member 71 toward one end of the auger member 71, i.e., in one paper dust transporting direction X.
  • the other side slant wall 82 extends between the other end of the central wall 80 and the front end of the other side first partition wall 78, and is continuous with the central wall 80.
  • the other side slant wall 82 provides a gradually narrowing space between the other side slant wall 82 and the auger member 71 toward the other end of the auger member 71, i.e., in the other paper dust transporting direction Y.
  • the lower end of the second partition wall 79 including the central wall 80 and slant walls 81, 82 is joined with an upper surface of the front side bottom wall 64, whereas the upper end of the second partition wall 79 extends to the lid member 85 described later.
  • the front side bottom wall 64 including the receiving surface 65 is divided into the paper dust falling portion 83 and the paper dust accumulators 84 by the regulation wall 76 provided by the first partition walls 77, 78 and the second partition wall 79.
  • the paper dust falling portion 83 is a region on the front side bottom wall 64 and at the axially center portion of the auger member 71 and below the first paper dust removing roller 9b and the first sponge member 9c, so that the paper dusts scraped off from the first paper dust removing roller 9b are falling on the region.
  • This region is an interior of the first partition walls 77, 78 and the second partition wall 79.
  • the paper dust accumulators 84 are regions on the front side bottom wall 64 and adjacent to each end of the auger member 71 where the paper dusts transported by the auger member 71 are accumulated. The latter regions are an exterior of the first partition walls 77, 78 and the second partition wall 79.
  • Paper dusts scraped off at the multiple purpose transport portion 16, second transport portion 10 and first transport portion 9 and falling onto the paper dust falling portion 83 are transported toward the paper dust accumulators 84 at both ends of the auger member 71 according to the rotation of the auger member 71.
  • the one slant wall 81 and the other slant wall 82 of the second partition wall 79 are directed to gradually reduce the width of the transportation passage between the wall and the auger member 71 toward the transporting direction, paper dusts transported by the auger member 71 can be guided toward one side partition wall 77 and the other side partition wall 78 by the slant walls 81, 82.
  • the paper dusts transported by the auger member 71 can be smoothly and desirably moved past through the lower edge of the one and the other side partition walls 77, 78, and can reach the paper dust accumulators 84 each disposed downstream of the first partition walls.
  • the one side and other side partition walls 77, 78 can prevent paper dusts already accumulated in the paper dust accumulator 84 from being reversely moved, i.e., from being returned back to the paper dust falling portion 83 disposed upstream of the partition walls 77, 78 in the paper dust transporting direction. Consequently, sufficient falling length from the first transport portion 9 to the auger member 71 can be obtained at the paper dust falling portion 83. As a result, sufficient amount of paper dusts can be deposited on the paper dust falling portion 83, and can be removed therefrom.
  • the paper dust falling portion 83 is isolated from the first transport portion 9 by the regulation wall 76 as a region surrounding the lower front side of the first transport portion 9, the paper dusts can be fallen into the paper dust falling portion 83 and thereafter transported by the auger member 71. Accordingly, sufficient amount of paper dust removal can be attained with ensuring sufficient falling stroke from the first transport portion 9 to the auger member 71, while removing a greater amount of paper dusts at the first transport portion 9.
  • the regulation wall 76 is higher than the contacting region between the first paper dust removing roller 9b and the first sponge member 9c, the regulation wall 76 can prevent the paper dusts fallen from the first transport portion 9 from being scattered toward the external side of the regulation wall 76, i.e., toward the paper dust accumulators 84 and remaining area of the front side bottom wall 64.
  • the first transport portion 9 is in confrontation with the internal side of the regulation wall 76 defining the paper dust falling portion 83.
  • the paper dusts released from the first transport portion 9 are fallen onto the receiving surface 65 at a position below the auger member 71.
  • the slant surface 67 guides the paper dusts toward the auger member 71, and the paper dusts can be involved into the auger member 71 rotating downwardly at a side confronting to the slant surface 67. Accordingly, the paper dusts can be smoothly directed toward the paper dust accumulators 84.
  • the paper dusts After the paper dusts are transported to the paper dust accumulators 84, the paper dusts can be smoothly discharged from the auger member 71 into the paper dust accumulators 84 at the ridge portion 68 whose upper end is lower than the slant surface 67 and where the surface of the auger member 71 confronting the ridge portion 68 is moved upwardly.
  • the lid member 85 is provided above the front side bottom wall 64 for covering the regulation wall 76.
  • the lid member 85 is in a plate like shape and positioned below the bottom wall 63d of the partition plate 63.
  • the lid member 85 extends between the front wall of the main casing 2 and a position adjacent to the extension portion 62b positioned above the first paper dust removing roller 9b and first sponge member 9c.
  • a support portion 86 upstands from the front side bottom wall 64 for fixing the lid member 85 by a screw 87.
  • An opening 88 is provided between a rear side (a side of the sheet transport path 38) of the lid member 85 and the extension portion 62b.
  • the opening extends in the axial direction of the first paper dust removing roller 9b.
  • the opening 88 is provided between the lid member 85 and the extension portion 62, the paper dusts released from the second transport portion 10 and the multiple purpose transport portion 16 those positioned above the lid member 85 can be introduced into the paper dust falling portion 83 and the paper dust accumulators 84 through the opening 88. After the paper dusts released from the second transport portion 10 and multiple purpose transport portion 16 are introduced into the paper dust falling portion 83, these paper dusts can be transported to the paper dust accumulators 84 by the auger member 71. Thus, effective paper dust removal can be provided.
  • the lid member 85 is positioned higher than the contact region between the first paper dust removing roller 9b and the first sponge member 9c, the paper dusts released from the first transport portion 9 cannot be easily scattered outwardly through the opening 88. Thus, more effective paper dust removal can be attained.
  • the paper dust accumulators 84 can be disposed on the front side bottom wall 64 since the paper dusts removed by the multiple purpose transport portion 16, second transport portion 10 and first transport portion 9 are transported toward axial ends of the auger member 71 through rotation thereof. Therefore, it is unnecessary to provide a paper dust accumulation space at a position lower than the front side bottom wall 64. To this effect, the auger member 71 is disposed above the attachment/detachment space of the sheet supply tray 6. As a result, attachment/detachment work of the sheet supply tray 6 can be performed easily while ensuring smooth removal of the paper dusts from the sheet 3 supplied from the sheet supply tray 6.
  • the laser printer 1 is of an electro-photographic type laser printer in which an electrostatic latent image is developed into a visible image which in turn transferred onto the sheet 3. Therefore, it is absolutely necessary to remove the paper dusts from the paper otherwise the paper dusts may be mingled into the image forming section 5 at the time of image transfer. In the present embodiment however, paper dusts can be efficiently removed from the sheet 3 by the first and second transport portions 9, 10 and the multiple purpose transport portion 16.
  • residual toner remaining on the surface of the photosensitive drum 23 after the image transferring operation is collected by the developing roller 27 with a cleaner-less system of the electro-photographic printing system using the non-magnetic single component type toners. If the paper dusts from the sheet 3 is adhered onto the surface of the photosensitive drum 23 at the time of image transfer operation, the paper dust may be collected together with the residual toner by the developing roller 27 and may be mixed with the toner in the developing cartridge 24, to thus degrade the output image.
  • the paper dusts on the sheet 3 can be efficiently removed by the first and second transport portion 9, 10 and the multiple purpose transfer portion 16 in the image forming operation, and further, can be prevented the reversal transportation of the paper dusts into the sheet transport paths 38, 38a, the paper dusts having been scraped by the first sponge member 9c, second sponge member 10c and the multiple purpose sponge member 16c in spite of the reversal rotation of the first paper dust removing roller 9b, second paper dust removing roller 10b and multiple purpose paper dust removing roller 16b for removing the jamming sheet. Therefore, the subsequent sheet is not subjected to the adhesion of the paper dusts, and a desirable image can be formed while easily collecting the residual toner with the cleaner-less system.
  • the multiple purpose transport portion 16, the second transport portion 10, and the first transport portion 9 are arrayed substantially in the vertical direction and in front of the sheet transport path 38, and paper dusts removed by these portions 16, 10, 9 are respectively dropped because of their gravity through the chute 39 and are fallen onto the receiving portion 65. Thereafter, these paper dusts are congregately accumulated into the receiving portion 65. Accordingly, paper dusts removed at every multiple purpose transport portion 16, the second transport portion 10 and the first transport portion 9 can be guided with the simple arrangement and can be accumulated congregately. Thus, it is not necessary to provide each paper dust accumulator for each transport portion, which in turn simplifies the overall device, and can reduce numbers of mechanical components to provide a compact device.
  • the paper dust chute 39 since one side face of the guide plate 61 constituting the sheet transport path 38 can be utilized as the paper dust chute 39, which can also simplify the overall device, and can reduce numbers of mechanical components to provide a compact device.
  • the extension portion 62a prevents the paper dusts from falling onto the second transport portion 10, the paper dust being released from the multiple purpose transport portion 16 positioned above the second transport portion 10, and further, the extension portion 62b prevents the paper dusts from falling onto the first transport portion 9, the paper dust being released from the multiple purpose transport portion 16 as well as from the second transport portion 10 positioned above the first transport portion 9. Consequently, desirable paper dust removing operations in the first and second transport portions 9 and 10 can be attained for a long period.
  • the first paper dust removing roller 9b in the first transport portion 9 removes the paper dusts on the sheet 3 in rotational contact therewith, and then the paper dusts adhered onto the first paper dust removing roller 9b is scrapped off by the first sponge member 9c disposed opposite to the sheet transport path 38 with respect to the first paper dust removing roller 9b.
  • the second paper dust removing roller 10b in the second transport portion 10 removes the paper dusts on the sheet 3 in rotational contact therewith, and then the paper dusts adhered onto the second paper dust removing roller 10b is scrapped off by the second sponge member 10c disposed opposite to the sheet transport path 38 with respect to the second paper dust removing roller 10b.
  • the paper dusts scraped by the first and second sponge members 9c and 10c are stayed thereon in confrontation with the sheet transport path 38 and are grown into paper dust masses, whereupon each paper dust mass is dropped because of its gravity along the paper dust chute 39. In this way, entry of the scrapped paper dusts into the sheet transport path 38 can be prevented, while the paper dusts removed by the first and second transport portions 9 and 10 can be congregately accumulated in the paper dust accumulators 84.
  • the multiple purpose paper dust removing roller 16b in the multiple purpose transport portion 16 removes the paper dusts on the sheet 3 in rotational contact therewith, and then the paper dusts adhered onto the multiple purpose paper dust removing roller 16b is scrapped off by the multiple purpose sponge member 16c disposed opposite to the sheet transport path 38a with respect to the multiple purpose paper dust removing roller 16b.
  • the paper dusts scraped by the multiple purpose sponge members 16c are dropped because of its gravity along the paper dust chute 39. In this way, entry of the scrapped paper dusts into the sheet transport path 38a can be prevented, while the paper dusts removed by the multiple purpose transport portions 16 can be congregately accumulated in the paper dust accumulator.
  • FIG. 9 An image forming device according to a second embodiment of the present invention will be described with reference to Figs. 9 through 13(b) wherein like parts and components are designated by the same reference numerals and characters as those shown in the first embodiment shown in Figs. 1 through 8 .
  • a laser printer 101 according to the second embodiment is different from the first embodiment in terms of the arrangement of collection of paper dusts.
  • a second paper dust removing roller 110b is driven upon power input from a motor (not shown) into an input gear 110h as shown in Fig. 10 , serving as power input means mounted on one end portion of the roller shaft 110f, so that the second paper dust removing roller 110b is rotatable in a direction indicated by an arrow in Fig. 9 , that is, in the sheet feeding direction (counter clockwise direction in Fig. 9 ) at a region facing with the sheet transport path 38.
  • the sheet 3 is nipped between the second transport roller 10a and the second paper dust removing roller 110b for feeding, while the paper dust is removed by the second paper dust removing roller 110b.
  • a lower end of a second guide plate 161b is integrally provided with a receiving plate 161c bent at substantially right angle from the second guide plate 161b toward frontward.
  • the receiving plate 161c is positioned above an attachment/detachment path of the sheet supply tray 6 and extends in parallel therewith.
  • An upper surface of the receiving plate 161c surves as a receiving surface 165 adapted for receiving paper dusts removed by and falling from the multiple purpose transport portion 16, the second transport portion 10 and the first transport portion 9.
  • a partition plate 163 is positioned in front of the second guide plate 161b with a predetermined space therefrom.
  • the partition plate 163 includes a side plate 163c extending in a vertical direction and a bottom plate 163d bent at substantially right angle from a lower end of the side plate 163c toward frontward. Further, a plate-like fixing portion 163a bendingly extends upwardly from a front end of the bottom plate 163d for fixing a paper dust transport plate 166 and a transport drive portion 167 described later.
  • the laser printer 101 further provides a paper dust accumulators 168 for accumulating therein paper dusts falling onto the receiving surface 165 due to their gravity from the multiple purpose transport portion 16, the second transport portion 10 and the first transport portion 9.
  • the printer 101 also provides the paper dust transport plate 166 for transporting paper dusts on the receiving surface 165 toward the paper dust accumulators 168, and the transport drive portion 167 for driving the paper dust transport plate 166.
  • the paper dust accumulators 168 are positioned below the multiple purpose transfer portion 16, the second transfer portion 10 and the first transfer portion 9.
  • the paper dust accumulator 168 is provided at spaces located outward of the widthwise ends of the receiving surface 165, so that all paper dusts falling on the receiving surface 165 can be ultimately accumulated in the accumulators 168.
  • the paper dust transport plate 166 is positioned above the sheet supply tray attachment/detachment path and above the receiving surface 165.
  • the plate 166 includes a T-shaped plate like base portion 169 as viewed from the front as shown in Fig. 12 and a generally L-shaped thin plate-like wiper plate 170 as shown in Fig. 9 protruding rearwardly from and integrally with a widthwise center portion of the lower portion of the base portion 169 and extending downwardly to a position below the first transport portion 9.
  • the paper dust transport plate 166 has a T-shape in plan view in which the wiper plate 170 protrudes perpendicularly from the widthwise center portion of the base portion 169.
  • the base portion 169 is fixed to a rack 174 of the transport drive portion 167 through screws 171 interposing the fixing portion 163a of the partition plate 163 between the paper dust transport plate 166 and the rack 174.
  • the fixing portion 163a is formed with an elongated horizontally extending slot 163b through which the screws 171 extend.
  • the paper dust transport plate 166 is reciprocally and horizontally movable along the horizontally extending slot 163b in accordance with the horizontal movement of the rack 174.
  • a lower end of the wiper plate 170 is spaced away from the receiving surface 165 by a predetermined distance (about 2 mm) as shown in Fig. 9 , so that the lower end is out of sliding contact from the receiving surface 165 during reciprocating movement of the wiper plate 170.
  • the transport drive portion 167 is disposed above the paper dust transport plate 166 and the paper dust accumulator 168 as shown in Fig. 9 , and is separated from the first and second transport portions 9, 10 and the multiple purpose transport portion 16 by the partition plate 163.
  • the transport drive portion 167 includes a power transmission mechanism 194 (see Figs. 13(a) and 13(b) ), a first bevel gear 172, a composite gear 173 and the rack 174.
  • the power transmission mechanism 194 is disposed along a side wall of the main casing 2, and includes an input gear 177, a conversion gear portion 178 and an output gear 179.
  • the input gear 177 is fixedly mounted on one end of an input shaft 180 drivingly rotated in one direction by a motor (not shown).
  • the input gear 177 is meshedly engaged with a first conversion gear 181 of the conversion gear portion 178 described later.
  • the conversion gear portion 178 includes the first conversion gear 181, a second conversion gear 182, a pendulum member 183, and a third conversion gear 184.
  • the first conversion gear 181 has a large diameter first outer gear 185 meshedly engaged with the input gear 177, and a small diameter first inner gear 186 concentrically integral with the first outer gear 185 and meshedly engaged with the second conversion gear 182.
  • the second conversion gear 182 has a gear teeth meshedly engaged with the first inner gear 186 of the first conversion gear 181.
  • a cylindrical sleeve 187 extends from a wheel body of the second conversion gear 182 in an axial direction thereof at a position offset from the rotational center of the second conversion gear 182.
  • the sleeve 187 is loosely engaged with a slot 188 formed in the pendulum member 183.
  • the pendulum member 183 is a plate member in a form of an elongated sector shape.
  • the pendulum member 183 has a lower end formed with an arcuate teeth portion 189 meshedly engaged with a third inner gear 192 of the third conversion gear 184 described later.
  • the slot 188 is formed in a longitudinal direction of the pendulum member 183 and at a widthwise center thereof.
  • a pivot support 190 is provided between one end of the slot 188 and the arcuate teeth portion 189.
  • the pendulum member 183 is pivotally movably supported by the pivot support 190, while the sleeve 187 of the second conversion gear 182 is loosely engaged with the slot 188.
  • the third conversion gear 184 has a large diameter third outer gear 191 meshedly engaged with the output gear 179, and a small diameter third inner gear 192 provided integrally and concentrically with the third outer gear 191 and meshedly engaged with the arcuate teeth portion 189 of the pendulum member 183.
  • the output gear 179 is fixedly mounted on one end portion of an output shaft 193 which transmits power to the first bevel gear 172.
  • the output gear 179 is adapted for transmitting power from the third outer gear 191 of the third conversions gear 184 to the first bevel gear 172.
  • the first bevel gear 172 is mounted on another end portion of the output shaft 193 which transmits power from the output gear 179.
  • the first bevel gear 172 is meshedly engaged with a second bevel gear 176 of the composite gear 173 directing perpendicular to the first bevel gear 172.
  • the composite gear 173 has a pinion gear 175 meshedly engaged with the rack 174 and the second bevel gear 176 provided integrally with the pinion gear 175 and positioned in radially inner side thereof.
  • the pinion gear 175 is rotatable about a horizontal axis.
  • the rack 174 has a rack teeth 174a meshedly engaged with the pinion gear 175 of the composite gear 173.
  • the rack 174 has an elongated rectangular shape whose longitudinal length is slightly greater than the width of the first paper dust removing roller 9b.
  • the rack 174 extends in parallel with the axial direction of the first paper dust removing roller 9b in a state where the rack teeth 174a is meshedly engaged with the pinion gear 175.
  • the rack 174 is linearly reciprocatingly moved in the axial direction of the first paper dust removing roller 9b while a rear surface of the rack 174 is in sliding contact with the fixing portion 163a of the partition plate 163 ( Fig. 11 ).
  • the transport drive portion 167 including the gear transmission from the input gear 177 to the output gear 179 provides speed deceleration in such a manner that the reciprocal moving speed of the paper dust transport plate 166 is not more than 100 mm/sec.
  • the transport drive portion 167 is disposed above the paper dust transport plate 166 and the paper dust accumulator 168, and is isolated by the partition plate 163. Therefore, the partition plate 163 can effectively prevent paper dust from entering into the transport drive portion 167, the paper dust being released from the multiple purpose transport portion 16, the second transport portion 10 and the first transport portion 9 due to gravity, or transported by the paper dust transport plate 166, or the accumulated in the accumulator 168. As a result, operational malfunction of the transport drive portion 167 due to entry of the paper dust can be eliminated, to provide a stabilized operation thereof, thereby providing sufficient paper dust removing operation for a long duration of time.
  • the paper dust is wiped by the wiper 170 of the paper dust transport plate 166, the wiper being reciprocatingly moved in the horizontal direction, and is transported to the paper dust accumulators 168. Therefore, stabilized transportion of the paper dusts is achievable with a simple arrangement without any complicated transportation mechanism.
  • the wiper 170 is linearly reciprocatingly moved along the axial direction of the first paper dust removing roller 9b. Therefore, desirable transportation of the paper dusts toward the accumulator 168 can be attained without any residual paper dusts on the receiving surface 165 with a minimized space and simplified arrangement.
  • the wiper 170 is not a linear reciprocation type but a pivotally moving reciprocation type.
  • large pivotally moving locus is required, which in turn makes the entire device bulky.
  • a flexible blade member may be used which may be deformed or flexed in contacting with an opponent component.
  • a complicated arrangement is required for assembling the flexible blade and number of mechanical components may be increased.
  • the paper dust transport plate 166 is moved at a low speed such as not more than 100 mm/sec., the paper dusts on the receiving surface 165 can be transported to the accumulator 168 without any scattering of the paper dust. Accordingly, entry of the paper dust into the transport drive portion 167 can further be avoided, to attain desirable paper dust removing operation for a long duration of time.
  • the wiper 170 is spaced away from the receiving surface 165 by the predetermined gap (about 2 mm) while the wiper is reciprocatingly moved in the horizontal direction, frictional contact of the wiper 170 agaist the receiving surface 165 can be eliminated, to avoid damage to the wiper.
  • enhanced durability of the paper dust transport plate 166 results for providing efficient transportation of the paper dust.
  • the paper dusts falling onto the receiving surface 165 is not a fine particle but in the form of a mass, the paper dusts can still be wiped by the wiper 170 regardless of the predetermined gap. The gap does not affect the transportation of the paper dusts mass.
  • the paper dust transport plate 166 can be positioned above the attachment/detachment path of the sheet supply tray 6, yet performing efficient paper dust removal from the sheet supplied from the sheet supply tray 6, while ensuring smooth attachment/detachment of the sheet supply tray 6.
  • driving force in one direction input into the input gear 177 can be converted into the driving force in reciprocating direction through the conversion gear portion 178 in the power transmission mechanism 194, and thereafter, the reciprocally driving force is output to the paper dust transport plate 166 through the output gear 179.
  • one directional driving force can be converted into reciprocating directional driving force with the simple arrangement, to provide reciprocal motion of the paper dust transport plate 166.
  • first transport portion 9 and only one second transport portion 10 are provided.
  • a plurality of first transport portions and a plurality of second transport portions can be provided.
  • a plurality of transport portions can be provided for one of the first and second transport portions.
  • the first transport portion 9 provided with the first paper dust removing roller 9b is provided upstream of the second transport portion 10 provided with the second paper dust removing roller 10b.
  • the second transport portion 10 provided with the second paper dust removing portion 10b can be disposed upstream of the first transport portion 9 provided with the first paper dust removing roller 9b.
  • the width of the first paper dust removing roller 9a and the width of the first sponge member 9c should desirably be greater than the widths thereof in case of the arrangement where the first transport portion 9 is provided upstream of the second transport portion 10.
  • a center register type is applied for the sheet feeding from the sheet supply section 7 to the first transport portion 9, and the auger member 71 is adapted to transport paper dusts toward both axial ends thereof.
  • a side register type can be applied and the auger member 71 can be adapted for transporting the paper dusts to one side only, the one side being opposite to the sheet register portion.
  • the rotating direction of the auger 71 is such that the surface of the auger member 71 is moved downwardly at a side facing the first transport portion 9.
  • the rotating direction of the shaft member 72 of the auger member 71 is not restrictive, but the surface of the auger member can be moved upwardly at a side facing the first transport portion 9.
  • the second partition wall 79 of the regulation wall 76 includes the center wall 80 extending in parallel with the auger member 71 with a predetermined space therefrom, the one side slant wall 81 and the other side slant wall 82 extending from the ends of the center wall 80 toward the auger member 71 by bending at the ends of the center wall. These walls are integrally with each other.
  • the second partition wall is not limited to the above-described configuration. For example, a plurality of walls can be used to make a center wall with a slit between the neighboring walls. Alternatively, an opening or a notch can be formed at a longitudinally intermediate portion of the second partition wall 79.
  • the first reverse transportation preventive member 9m, the second reverse transportation preventive member 10m, and the multiple purpose reverse transportation preventive member 16m are positioned spaced away from the corresponding first paper dust removing roller 9b, second paper dust removing roller 10b, and multiple purpose paper dust removing roller 16b, respectively.
  • these preventive members 9m, 10m, 16m can be contacted with the corresponding rollers by constituting these preventive members by brushes, films and unwoven fabrics those allowing the paper dusts to be transported during the normal rotation of the paper dust removing rollers 9b, 10b, 16b, but preventing the paper dusts from passing therethrough during reversal rotation of these rollers.
  • the second paper dust removing roller 10b, 110b has a width perpendicular to the sheet feeding direction greater than the width of the sheet 3 for removing the paper dusts from overall surface of the sheet 3.
  • paper dusts generated upon sheet cutting is particularly located adjacent to the cutting edge, i.e., widthwise edge potions of the sheet 3. Therefore, as shown in Fig. 14 , two second paper dust removing roller 10b' are provided on a roller shaft 10f' at positions corresponding to the widthwise edge portions of the sheet 3 for removing the paper dust from the sheet 3 at least in areas corresponding to the widthwise edge portions of the sheet 3.
  • the present invention is particularly available for the sheet supply section 7 in which sheet separation is achieved by making use of a friction, which easily provides paper dusts.
  • the present invention is also available for another sheet separation systems other than frictional separation, such as a system using pawls or a system using a bank.

Claims (53)

  1. Bilderzeugungsvorrichtung (1) zum Erzeugen eines Bildes an einem Bildaufzeichnungsmedium (3), wobei die Vorrichtung Folgendes aufweist:
    einen Blattzuführbereich (7), der eine Blattzuführwalze (12) und einen Trennblock (13) hat, um dazwischen jedes Bildaufzeichnungsmedium (3) greifend zuzuführen;
    einen Bilderzeugungsbereich (5) zum Erzeugen eines Bildes an dem Aufzeichnungsmedium (3), das von dem Blattzuführbereich (7) zugeführt wird; und
    einen Blatttransportpfad (38), der sich von dem Blattzuführbereich (7) zu dem Bilderzeugungsbereich (5) erstreckt und eine Blattvorschubrichtung definiert;
    eine erste Papierstaubbeseitigungseinheit (9), die an einer Position neben dem Blatttransportpfad (38) angeordnet ist und mit dem Bildaufzeichnungsmedium (3) in Kontakt treten kann, um Papierstaub von dem Bildaufzeichnungsmedium (3) zu beseitigen, das in dem Blatttransportpfad zu dem Bilderzeugungsbereich (5) wandert,
    gekennzeichnet durch zumindest: eine zweite Papierstaubbeseitigungseinheit (10), die an einer Position neben dem Blatttransportpfad (38) und hinsichtlich der Blattvorschubrichtung an einer anderen Position als die erste Papierstaubbeseitigungseinheit (9) angeordnet ist und auch mit dem Bildaufzeichnungsmedium (3) in Kontakt treten kann, um auch Papierstaub von dem Bildaufzeichnungsmedium (3) zu beseitigen, das in dem Blatttransportpfad (38) zu dem Bilderzeugungsbereich (5) wandert;
    wobei das Bildaufzeichnungsmedium (3) und der Trennblock (13) jeweils eine Breite haben, die senkrecht zu der Blattvorschubrichtung ist, und
    wobei ein erstes Papierstaubbeseitigungselement (9b) eine Fläche zum Beseitigen des Papierstaubs von dem Bildaufzeichnungsmedium (3) zumindest in einer Fläche hat, die der Breite (B) des Trennblocks (13) entspricht; und
    wobei ein zweites Papierstaubbeseitigungselement (10b) eine Fläche zum Beseitigen des Papierstaubs von der gesamten Oberfläche des Bildaufzeichnungsmediums (3) hat,
    wobei die erste Papierstaubbeseitigungseinheit (9) das erste Papierstaubbeseitigungselement (9b) aufweist, das mit dem Bildaufzeichnungsmedium (3) während dessen Bewegung in dem Blatttransportpfad in Kontakt ist; und
    wobei die zweite Papierstaubbeseitigungseinheit (10) das zweite Papierstaubbeseitigungselement (10b) aufweist, das mit dem Bildaufzeichnungsmedium (3) während dessen Bewegung in dem Blatttransportpfad (38) in Kontakt ist, und
    wobei die Breite des ersten Papierstaubbeseitigungselements (9b) kleiner ist als die Breite des zweiten Papierstaubbeseitigungselements (10b).
  2. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei die zweite Papierstaubbeseitigungseinheit (10) eine Breite senkrecht zu der Blattvorschubrichtung hat, die größer ist als die Breite (A) des Bildaufzeichnungsmediums (3).
  3. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei das erste Papierstaubbeseitigungselement (9b) eine Breite senkrecht zu der Blattvorschubrichtung hat, die größer ist als die Breite (B) des Trennblocks (13) und kleiner ist als die Breite (A) des Bildaufzeichnungsmediums (B).
  4. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei die zweite Papierstaubbeseitigungseinheit (10) stromabwärts von der ersten Papierstaubbeseitigungseinheit (9) in der Blattvorschubrichtung angeordnet ist.
  5. Bilderzeugungsvorrichtung gemäß Anspruch 1, des Weiteren mit einem Antriebskrafteingabeelement, das zumindest mit dem zweiten Papierstaubbeseitigungselement (10b) verbunden ist, um das zweite Papierstaubbeseitigungselement (10b) drehend anzutreiben.
  6. Bilderzeugungsvorrichtung gemäß Anspruch 2, wobei der Blattzuführbereich des Weiteren eine Blattzuführablage (6) aufweist, an der viele Bildaufzeichnungsmedien (3) als ein Blattstapel gestapelt sind, wobei die Blattzuführwalze (12) und der Trennblock (13) ein oberstes Blatt (3) von dem Blattstapel trennen und das oberste Blatt (3) zu dem Bilderzeugungsbereich zuführen; und
    wobei das erste Papierstaubbeseitigungselement (9b) und das zweite Papierstaubbeseitigungselement (10b) stromabwärts von der Blattzuführwalze (12) in der Blattvorschubrichtung und außer Kontakt von der Blattzuführwalze (12) angeordnet sind.
  7. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei die erste Papierstaubbeseitigungseinheit (9) des Weiteren ein erstes Schabelement (9c) aufweist, dass gegenüber dem ersten Papierstaubbeseitigungselement (9b) angeordnet ist, um den Papierstaub abzuschaben, der an dem ersten Papierstaubbeseitigungselement (9b) haftet; und
    wobei die zweite Papierstaubbeseitigungseinheit (10) des Weiteren ein zweites Schabelement (10c) aufweist, das gegenüber dem zweiten Papierstaubbeseitigungselement (10b) angeordnet ist, um den Papierstaub abzuschaben, der an dem zweiten Papierstaubbeseitigungselement (10b) haftet.
  8. Bilderzeugungsvorrichtung gemäß Anspruch 7, wobei das erste und das zweite Papierstaubbeseitigungselement (9b, 10b) Bereiche haben, die dem Blatttransportpfad (38) gegenüberliegen, wobei die Bereiche in der Blattvorschubrichtung bewegbar sind; und
    wobei das erste und das zweite Schabelement (9c, 10c) jeweils an Positionen gegenüber dem Blatttransportpfad (38) hinsichtlich des ersten und des zweiten Papierstaubbeseitigungselements (9b, 10b) und unter dem ersten und dem zweiten Papierstaubbeseitigungselement (9b, 10b) angeordnet sind.
  9. Bilderzeugungsvorrichtung gemäß Anspruch 8, wobei das erste Papierstaubbeseitigungselement (9b) und das zweite Papierstaubbeseitigungselement (10b) in einer normalen Drehrichtung, die die Blattvorschubrichtung ist, und auch in einer Rückwärtsdrehrichtung drehbar sind, die der Blattvorschubrichtung entgegengesetzt ist; und
    wobei die erste Papierstaubbeseitigungseinheit (9) des Weiteren ein erstes Rückwärtstransportverhinderungselement (9m) aufweist, das zwischen einer ersten Kontaktposition zwischen dem ersten Papierstaubbeseitigungselement (9b) und dem Bildaufzeichnungsmedium (3) und einer zweiten Kontaktposition zwischen dem ersten Papierstaubbeseitigungselement (9b) und dem ersten Schabelement (9c) angeordnet ist, um zu verhindern, dass der von dem ersten Schabelement (9c) gelöste Papierstaub zu dem Blatttransportpfad (38) während der Rückwärtsdrehung des ersten Papierstaubbeseitigungselements (9b) transportiert wird.
  10. Bilderzeugungsvorrichtung gemäß Anspruch 9, wobei die zweite Papierstaubbeseitigungseinheit (10) des Weiteren ein zweites Rückwärtstransportverhinderungselement (10m) aufweist, das zwischen einer ersten Kontaktposition zwischen dem zweiten Papierstaubbeseitigungselement (10b) und dem Bildaufzeichnungsmedium (3) und einer zweiten Kontaktposition zwischen dem zweiten Papierstaubbeseitigungselement (10b) und dem zweiten Schabelement (10c) angeordnet ist, um zu verhindern, dass der von dem zweiten Schabelement (10c) gelöste Papierstaub zu dem Blatttransportpfad (38) während der Rückwärtsdrehung des zweiten Papierstaubbeseitigungselements (10b) transportiert wird.
  11. Bilderzeugungsvorrichtung gemäß Anspruch 1, des Weiteren mit:
    einer ersten Transportwalze (9a), die gegenüber dem ersten Papierstaubbeseitigungselement (9b) angeordnet ist, um das Bildaufzeichnungsmedium (3) in einem Greifzustand mit dem ersten Papierstaubbeseitigungselement (9b) zu transportieren; und
    eine zweite Transportwalze (10a), die gegenüber dem zweiten Papierstaubbeseitigungselement (10b) angeordnet ist, um das Bildaufzeichnungsmedium (3) in einem Greifzustand mit dem zweiten Papierstaubbeseitigungselement (lob) zu transportieren.
  12. Bilderzeugungsvorrichtung gemäß Anspruch 1, des Weiteren mit einem Blattrückzirkulationsbereich (41), der einen Blattrückzirkulationspfad (53) und einen Blattumkehrbereich (42) einschließt, der an dem Blattrückzirkulationspfad (53) angeordnet ist, wobei der Blattrückzirkulationspfad (53) ein stromaufwärtiges Ende, das mit dem Bilderzeugungsbereich (5) verbunden ist, um das von dem Bilderzeugungsbereich (5) ausgelassene Bildaufzeichnungsmedium (3) aufzunehmen, an dessen einen Fläche ein Bild erzeugt wurde, und um das Bildaufzeichnungsmedium (3) zu dem Blattumkehrbereich (42) zu liefern, und ein stromabwärtiges Ende hat, das an dem Blatttransportpfad (38) an einem Fügeabschnitt stromaufwärts von dem Bilderzeugungsbereich (5) gefügt ist, um das Bildaufzeichnungsmedium (3) von dem Blattumkehrbereich (42) zu dem Bilderzeugungsbereich (5) vorzuschieben, um ein anderes Bild an einer anderen Fläche des Bildaufzeichnungsmediums (3) zu erzeugen, wobei das erste Papierstaubbeseitigungselement (9b) stromaufwärts von dem Fügebereich positioniert ist und das zweite Papierstaubbeseitigungselement (10b) stromabwärts von dem Fügeabschnitt positioniert ist.
  13. Bilderzeugungsvorrichtung gemäß Anspruch 1, des Weiteren mit einem Papierstaubsammelbereich (84), um darin Papierstaub anzusammeln, der zumindest durch zwei Papierstaubbeseitigungseinheiten (9, 10) von dem Bilderzeugungsmedien (3) beseitigt und dann von den jeweiligen Papierstaubbeseitigungseinheiten (9, 10) gelöst wurde.
  14. Bilderzeugungsvorrichtung gemäß Anspruch 13, wobei der Papierstaubsammelbereich (84) an einer Position angeordnet ist, die niedriger ist als die zumindest zwei Papierstaubbeseitigungseinheiten (9, 10), um darin den Papierstaub aufzunehmen, der von den jeweiligen Papierstaubbeseitigungseinheiten (9, 10) gelöst wurde und aufgrund der Schwerkraft des Papierstaubs nach unten gefallen ist.
  15. Bilderzeugungsvorrichtung gemäß Anspruch 14, des Weiteren mit einem Papierstaubablagerungsbereich (83), der niedriger als die zumindest zwei Papierstaubbeseitigungseinheiten (9, 10) positioniert ist.
  16. Bilderzeugungsvorrichtung gemäß Anspruch 15, des Weiteren mit einer Papierstaubtransporteinheit (71), die angrenzend an dem Papierstaubablagerungsbereich (83) angeordnet ist, um den an dem Papierstaubablagerungsbereich (83) abgelagerten Papierstaub zu dem Papierstaubsammelbereich (84) zu transportieren.
  17. Bilderzeugungsvorrichtung gemäß Anspruch 16, wobei der Papierstaubsammelbereich (84) an jeder Seite des Papierstaubablagerungsbereichs (83) in der Breitenrichtung des Bildaufzeichnungsmediums (3) angeordnet ist, um als ein Papierstaubsammelpaar zu funktionieren, und
    wobei die Papierstaubtransporteinheit (71) eine Wischerplatte aufweist, die in der Breitenrichtung des Bildaufzeichnungsmediums (3) über dem Papierstaubablagerungsbereich (83) und teilweise über dem Papierstaubsammelpaar hin und her bewegbar ist.
  18. Bilderzeugungsvorrichtung gemäß Anspruch 16, wobei der Papierstaubsammelbereich (84) an jeder Seite des Papierstaubablagerungsbereiches (83) in der Breitenrichtung des Bildaufzeichnungsmediums (3) angeordnet ist, um als ein Papierstaubsammelpaar zu wirken, und
    wobei die Papierstaubtransporteinheit (71) ein Schneckenelement (71) aufweist, das sich in der Breitenrichtung des Bildaufzeichnungsmediums (3) über dem Papierstaubablagerungsbereich (83) und teilweise über dem Papierstaubsammelpaar erstreckt, wobei das Schneckenelement (71) um seine Achse drehbar ist.
  19. Bilderzeugungsvorrichtung gemäß Anspruch 16, des Weiteren mit einer Regulierwandkomponente (76, 77, 78), die so angeordnet ist, dass sie die Papierstaubtransporteinheit (71) schneidet, wobei die Regulierwandkomponente (76, 77, 78) den Papierstaubablagerungsbereich (83) von dem Papierstaubsammelbereich (84) trennt.
  20. Bilderzeugungsvorrichtung gemäß Anspruch 15, des Weiteren mit einer Papierstaubrinne (39), um den nach unten fallenden Papierstaub zu führen und um den Papierstaub zu dem Papierstaubablagerungsbereich (83) zu leiten.
  21. Bilderzeugungsvorrichtung gemäß Anspruch 20, wobei der Blatttransportpfad (38) eine Führungsplatte (61) aufweist, die eine Fläche hat, die eine Bewegung des Bildaufzeichnungsmediums (3) führt; und
    wobei die Führungsplatte (61) eine entgegengesetzte Fläche hat, die als die Papierstaubrinne (39) dient.
  22. Bilderzeugungsvorrichtung gemäß Anspruch 21, wobei die Führungsplatte (61) mit einer ersten Erweiterungsplatte (61b), die unmittelbar über der ersten Papierstaubbeseitigungseinheit (9) angeordnet ist, und mit einer zweiten Erweiterungsplatte (61a) versehen ist, die unmittelbar über der zweiten Papierstaubbeseitigungseinheit (10) angeordnet ist.
  23. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei die zumindest zwei Papierstaubbeseitigungseinheiten (9, 10) in einer im Wesentlichen vertikalen Richtung an einer entsprechenden Seite des Blatttransportpfades (38) aufgereiht sind.
  24. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei der Bilderzeugungsbereich (5) elektrophotographische Systemkomponenten aufweist, in denen ein sichtbares Bild bei einer Entwicklung eines elektrostatischen, latenten Bildes auf das Bildaufzeichnungsmedium (3) übertragen wird.
  25. Bilderzeugungsvorrichtung gemäß Anspruch 24, wobei der Bilderzeugungsbereich (5) Folgendes aufweist:
    eine lichtempfindliche Trommel (23), an der das elektrostatische, latente Bild erzeugt wird; und
    eine Entwicklungsvorrichtung (24), die ein Entwicklermittel zu der lichtempfindlichen Trommel (23) zuführt, wobei das Entwicklungsmittel Mittel einer nicht-magnetischen, einzigen Komponente aufweist; die Entwicklungsvorrichtung außerdem restliches Entwicklungsmittel sammelt, das an der lichtempfindlichen Trommel (23) verbleibt, nachdem das Bild von der lichtempfindlichen Trommel zu dem Bildaufzeichnungsmedium übertragen wurde.
  26. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei das Bildaufzeichnungsmedium (3) und der Trennblock (13) jeweils eine Breite haben, die senkrecht zu der Blattvorschubrichtung ist, und
    wobei das erste Papierstaubbeseitigungselement (9b) eine Fläche zum Beseitigen des Papierstaubs von dem Bildaufzeichnungsmedium (3) zumindest in einer Fläche hat, die der Breite (B) des Trennblocks (13) entspricht, und
    wobei das zweite Papierstaubbeseitigungselement (10b) eine Fläche zum Beseitigen des Papierstaubs von dem Bildaufzeichnungsmedium (3) zumindest in Flächen hat, die den Kantenabschnitten in der Breite des Bildaufzeichnungsmediums (3) entsprechen.
  27. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei
    Schabelemente (9c, 10c) mit dem ersten bzw. zweiten Papierstaubbeseitigungselement (9b, 10b) in Kontakt sind, um den Papierstaub von dem ersten und dem zweiten Papierstaubbeseitigungselement (9b, 10b) abzuschaben, wobei die Papierstaubbeseitigungselemente (9b, 10c) in einer normalen Richtung, die äquivalent zu der Blattvorschubrichtung ist, und in einer Rückwärtsrichtung entgegen der normalen Richtung drehbar gestützt sind; und
    wobei das erste und das zweite Rückwärtstransportverhinderungselement (9m, 10m) zwischen einer ersten Kontaktposition, die zwischen dem ersten bzw. zweiten Papierstaubbeseitigungselement (9b, 10b) und dem Bildaufzeichnungsmedium (3) definiert ist, und einer zweiten Kontaktposition angeordnet sind, die zwischen dem ersten bzw. zweiten Papierstaubbeseitigungselement (9b, 10b) und den Schabelementen (9c, 10c) definiert ist, um zu verhindern, dass der von dem Schabelement (9c, 10c) gelöste Papierstaub während der Rückwärtsdrehung des ersten bzw. zweiten Papierstaubbeseitigungselements (9b, 10b) zu dem Blatttransportpfad (38) zurück transportiert wird.
  28. Bilderzeugungsvorrichtung gemäß Anspruch 27, wobei das erste Rückwärtstransportverhinderungselement (9m) und das erste Papierstaubbeseitigungselement (9b, ) dazwischen einen Spalt (L) vorsehen, wobei der Spalt (L) ein Maß bereitstellt, das es ermöglicht, dass der Papierstaub während der normalen Drehung des ersten Papierstaubbeseitigungselements (9b, ) dort hindurch tritt, das es aber verhindert, dass der Papierstaub während der Rückwärtsdrehung des ersten Papierstaubbeseitigungselements (9b, ) dort hindurch tritt.
  29. Bilderzeugungsvorrichtung gemäß Anspruch 28, wobei der Spalt (L) eine Länge hat, die in einem Bereich von 0,2 bis 2 mm ist.
  30. Bilderzeugungsvorrichtung gemäß Anspruch 27, wobei das erste Rückwärtstransportverhinderungselement (9m, ) einen Spitzenendabschnitt (9p,) hat, der eine Orientierung hat, wobei ein Schnittwinkel (θ) zwischen einer Tangente (Y) und einer Erweiterungslinie (Z) definiert ist, die die Orientierung des Spitzenendabschnitts (9p,) ist, wobei die Tangente (Y) an dem ersten Papierstaubbeseitigungselement (9b,) hinsichtlich einer Linie liegt, die ein Spitzenende (9t,) des Spitzenendabschnitts (9p,) und eine Drehmitte des ersten Papierstaubbeseitigungselements (9b,) verbindet, und wobei der Schnittwinkel (θ) nicht größer als 90° ist.
  31. Bilderzeugungsvorrichtung gemäß Anspruch 30, wobei der Spitzenendabschnitt (9p,) stromaufwärts von der Linie angeordnet ist, die das Spitzenende (9t,) des Spitzenendabschnitts (9p,) und die Drehmitte des Papierstaubbeseitigungselements (9b,) verbindet, und zwar in der normalen Drehrichtung des ersten Papierstaubbeseitigungselements (9b).
  32. Bilderzeugungsvorrichtung gemäß Anspruch 30, wobei der Spitzenendabschnitt (9p,) des ersten Rückwärtstransportverhinderungselements (9b,) so orientiert ist, dass er dem Papierstaub direkt entgegengesetzt wird, der an dem ersten Papierstaubbeseitigungselement (9b,) während dessen Rückwärtsdrehung transportiert wird.
  33. Bilderzeugungsvorrichtung gemäß Anspruch 27, wobei das erste und das zweite Rückwärtstransportverhinderungselement (9m, 10m) jeweils eine Breite haben, die sich in einer Richtung senkrecht zu der Blattvorschubrichtung erstreckt und größer ist als eine Breite des jeweiligen ersten bzw. zweiten Papierstaubbeseitigungselements (9b, 10b).
  34. Bilderzeugungsvorrichtung gemäß Anspruch 27, wobei das erste und das zweite Rückwärtstransportverhinderungselement (9m, 10m) jeweils eine Breite haben, die sich in einer Richtung senkrecht zu der Blattvorschubrichtung erstreckt und größer ist als eine Breite des jeweiligen ersten bzw. zweiten Schabelementes (9c, 10c).
  35. Bilderzeugungsvorrichtung gemäß Anspruch 27, des Weiteren mit einem Gehäuse (100a, 100b), das das erste und das zweite Papierstaubbeseitigungselement (9b, 10b) und das Schabelement (9c, 10c) stützt, wobei das erste und das zweite Rückwärtstransportverhinderungselement (9m, 10m) einstückig mit dem Gehäuse (100a, 100b) vorgesehen sind.
  36. Bilderzeugungsvorrichtung gemäß Anspruch 27, wobei das erste und das zweite Rückwärtstransportverhinderungselement (9m, 10m) eine Seite, die dem ersten bzw. zweiten Papierstaubbeseitigungselement (9b, 10b) entgegengesetzt ist, und eine andere Seite haben, die als ein Führungselement zum Führen des Papierstaubs nach unten dient, wobei der Papierstaub auf das jeweilige Rückwärtstransportverhinderungselement (9m, 10m) gefallen ist.
  37. Bilderzeugungsvorrichtung gemäß Anspruch 27, des Weiteren mit einem ersten und einem zweiten Transportelement (9a, 10a), das mit dem ersten bzw. zweiten Papierstaubbeseitigungselement (9b, 10b) in Kontakt ist, um das Bildaufzeichnungsmedium (3) entlang des Transportpfades (38) zu transportieren.
  38. Bilderzeugungsvorrichtung gemäß Anspruch 1, wobei
    die Papierstaubtransporteinheit (71) niedriger als die erste Papierstaubbeseitigungseinheit (9) angeordnet ist, um den Papierstaub, der von der ersten Papierstaubbeseitigungseinheit (9) herunter fällt, in einer Papierstaubtransportrichtung zu transportieren; und
    eine Regulierwand (76) an einem Teil der Papierstaubtransporteinheit (71) angeordnet ist, um einen Fluss des Papierstaubs zu regulieren.
  39. Bilderzeugungsvorrichtung gemäß Anspruch 38, des Weiteren mit einem Papierstaubablagerungsbereich (83), der niedriger als die erste Papierstaubbeseitigungseinheit (9) angeordnet ist, und einem Papierstaubsammelbereich (84), der neben dem Papierstaubablagerungsbereich (83) in der Breitenrichtung des Bildaufzeichnungsmediums (3) positioniert ist; und
    wobei die Regulierwand (76) einen Wandbereich (77, 78) aufweist, der den Papierstaubablagerungsbereich (83) von dem Papierstaubsammelbereich (84) trennt, wobei der Papierstaubablagerungsbereich (83) Papierstaub aufnimmt, der von der ersten Papierstaubbeseitigungseinheit (9) herunter fällt, und wobei der Papierstaubsammelbereich (84) darin den Papierstaub sammelt, der durch die Papierstaubtransporteinheit (71) aus dem Papierstaubablagerungsbereich (83) transportiert wird, wobei der Wandbereich (77, 78) eine Form und ein Maß hat, das es ermöglicht, dass der Papierstaub aus dem Papierstaubablagerungsbereich (83) zu dem Papierstaubsammelbereich (84) während des Transports des Papierstaubs durch die Papierstaubtransporteinheit (71) befördert wird, das es aber verhindert, dass der Papierstaub von dem Papierstaubsammelbereich (84) zu dem Papierstaubablagerungsbereich (83) bewegt wird.
  40. Bilderzeugungsvorrichtung gemäß Anspruch 38, wobei die Papierstaubtransporteinheit (71) ein drehbares Schneckenenvorschubelement (71) mit einer Drehachse aufweist, wobei der Papierstaub in einer Richtung der Drehachse durch die Drehung des Schneckenvorschubelements (71) transportiert wird.
  41. Bilderzeugungsvorrichtung gemäß Anspruch 40, wobei das drehbare Schneckenvorschubelement (71) Folgendes aufweist:
    eine Drehwelle (72), die um ihre Achse drehbar ist und einen Zwischenabschnitt und Endabschnitte hat;
    ein erstes Schneckenelement (73), das eine erste Schneckenrichtung hat und über eine rechte Hälfte der Drehwelle (72) ausgebildet ist; und
    ein zweites Schneckenelement (74), das eine zweite Schneckenrichtung entgegen der ersten Schneckenrichtung hat und über eine linke Hälfte der Drehwelle (72) ausgebildet ist, wodurch der Papierstaub zu beiden axialen Enden der Drehwelle (72) transportiert wird.
  42. Bilderzeugungsvorrichtung gemäß Anspruch 41, wobei der Papierstaubablagerungsbereich (83) an dem Zwischenabschnitt der Drehwelle (72) angeordnet ist und der Papierstaubsammelbereich (84) zwei Papierstaubsammelzonen aufweist, die sich angrenzend an den axialen Endabschnitten der Drehwelle (72) befinden.
  43. Bilderzeugungsvorrichtung gemäß Anspruch 40, wobei das drehbare Schneckenvorschubelement (71) einen gegenüberliegenden Bereich gegenüber der ersten Papierstaubbeseitigungseinheit (9) hat, wobei der gegenüberliegende Bereich durch die Drehung des Schneckenvorschubelements (71) nach unten bewegt wird.
  44. Bilderzeugungsvorrichtung gemäß Anspruch 43, des Weiteren mit einem Papierstaubaufnahmeabschnitt (65), der den Papierstaubablagerungsbereich (83) enthält, wobei der Papierstaubaufnahmebereich (65) unter der Papierstaubtransporteinheit (71) positioniert ist, wobei der Papierstaubaufnahmeabschnitt (65) einen sich längs erstreckenden, ausgesparten Abschnitt (66), in dem die Papierstaubtransporteinheit (71) positioniert ist, eine schräge Fläche (67) an einer sich längs erstreckenden Seite des ausgesparten Abschnitts (66) und gegenüber einer sich längs erstreckenden Seite des Vorschubelements (71) und einen Kantenabschnitt (68) gegenüber der schrägen Fläche (67) hinsichtlich des Vorschubelements (71) aufweist, wobei das Vorschubelement (71) eine sich längs erstreckende Seite hat, die zu der schrägen Fläche (67) nach unten bewegbar ist, und wobei das Vorschubelement (71) eine andere sich längs erstreckende Seite hat, die zu dem Kantenabschnitt (68) nach oben bewegbar ist, wobei das Kantenelement (68) eine Höhe hat, die niedriger ist als die schräge Fläche (67).
  45. Bilderzeugungsvorrichtung gemäß Anspruch 44, wobei ein Blattzuführbereich (7) zum Zuführen des Bildaufzeichnungsmediums (3) zu dem Bilderzeugungsbereich (5) dient, und wobei die erste Papierstaubbeseitigungseinheit (9) in einen ersten Kontakt mit dem Bildaufzeichnungsmedium (3) angeordnet wird, nachdem das Medium (3) von dem Blattzuführbereich (7) zugeführt wurde.
  46. Bilderzeugungsvorrichtung gemäß Anspruch 38, wobei die Regulierwand (76) Folgendes aufweist:
    eine erste Trennwand (77, 78), die die Papierstaubtransporteinheit (71) in einer Richtung trennt, die sich mit ihr schneidet, und
    eine zweite Trennwand (79), die mit der ersten Trennwand (77, 78) verbunden und mit einem Zwischenraum von der Papierstaubtransporteinheit (71) positioniert ist, wobei die zweite Trennwand (79) den Zwischenraum von der Papierstaubtransporteinheit (71) so vorsieht, dass er sich zu der Papierstaubtransportrichtung allmählich verengt.
  47. Bilderzeugungsvorrichtung gemäß Anspruch 40, wobei die Papierstaubtransporteinheit (71) eine Drehzahl vorsieht, die kleiner ist als eine Drehzahl des Papierstaubbeseitigungselements (9b).
  48. Bilderzeugungsvorrichtung gemäß Anspruch 7, wobei das Papierstaubbeseitigungselement (9b) und das Schabelement (9c) dazwischen einen Kontaktabschnitt vorsehen, wobei die Regulierwand (76) ein oberes Ende hat, das höher als der Kontaktabschnitt ist.
  49. Bilderzeugungsvorrichtung gemäß Anspruch 38, des Weiteren mit einem Deckelelement (85), das einen oberen Raum der Regulierwand (76) abdeckt.
  50. Bilderzeugungsvorrichtung gemäß Anspruch 47, des Weiteren mit der zweiten Papierstaubbeseitigungseinheit (10), die an einer Position über der Regulierwand (76) und an einer Position angeordnet ist, die sich von jener der ersten Papierstaubbeseitigungseinheit (9) in der Blattvorschubrichtung unterscheidet, um den Papierstaub von dem Bildaufzeichnungsmedium (3) zu beseitigen, das zu dem Bilderzeugungsbereich (5) zuzuführen ist.
  51. Bilderzeugungsvorrichtung gemäß Anspruch 50, wobei das Deckelelement (85) mit einer Öffnung ausgebildet ist, durch die der Papierstaub, der von der zweiten Papierstaubbeseitigungseinheit (10) fällt, in einen Innenraum der Regulierwand eintritt.
  52. Bilderzeugungsvorrichtung gemäß Anspruch 51, wobei die Öffnung (88) höher positioniert ist als der Kontaktabschnitt zwischen dem Papierstaubbeseitigungselement (9) und dem Schabelement (9c) der ersten Papierstaubbeseitigungseinheit (9).
  53. Bilderzeugungsvorrichtung gemäß Anspruch 52, des Weiteren mit einer Ablage (14), die hinsichtlich eines Hauptgehäuses (2) zum Stapeln von vielen Bildaufzeichnungsmedien (3) abnehmbar vorgesehen ist, wobei das Hauptgehäuse (2) mit einem Anbringungs-/Entnahmepfad für die Ablage (14) ausgebildet ist, und wobei die Papierstaubtransporteinheit (71) über dem Anbringungs-/Entnahmepfad angeordnet ist.
EP02020402.0A 2001-09-10 2002-09-10 Bilderzeugungsgerät mit Einheiten zum Entfernen von Papierstaub Expired - Lifetime EP1291729B1 (de)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
JP2001274323A JP4429555B2 (ja) 2001-09-10 2001-09-10 画像形成装置
JP2001274323 2001-09-10
JP2001274325A JP4203785B2 (ja) 2001-09-10 2001-09-10 画像形成装置
JP2001274325 2001-09-10
JP2002067642A JP3835318B2 (ja) 2002-03-12 2002-03-12 画像形成装置
JP2002067641 2002-03-12
JP2002067642 2002-03-12
JP2002067641A JP3750618B2 (ja) 2002-03-12 2002-03-12 画像形成装置

Publications (3)

Publication Number Publication Date
EP1291729A2 EP1291729A2 (de) 2003-03-12
EP1291729A3 EP1291729A3 (de) 2003-05-07
EP1291729B1 true EP1291729B1 (de) 2013-06-19

Family

ID=27482545

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02020402.0A Expired - Lifetime EP1291729B1 (de) 2001-09-10 2002-09-10 Bilderzeugungsgerät mit Einheiten zum Entfernen von Papierstaub

Country Status (3)

Country Link
EP (1) EP1291729B1 (de)
CN (1) CN100397246C (de)
HK (1) HK1053358A1 (de)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4013148B2 (ja) * 2004-03-09 2007-11-28 村田機械株式会社 画像形成装置
CN100386696C (zh) * 2005-07-29 2008-05-07 虹光精密工业（苏州）有限公司 具有静电集尘功能的馈纸装置
CN102785487B (zh) * 2012-08-24 2015-07-29 东莞井上五金橡塑有限公司 一种无研磨粉尘粒的清洁滚筒
CN111930084B (zh) * 2020-08-04 2022-09-23 广东理文造纸有限公司 基于纸面尘埃检测的无尘纸生产控制系统及方法
CN113301451B (zh) * 2021-04-13 2023-05-09 广州良驹信息科技有限公司 一种基于网络科技用家庭防尘快速冷却机构
CN114671293A (zh) * 2022-05-24 2022-06-28 江苏启航研磨科技有限公司 一种砂纸加工用具有砂粒压平功能的砂纸送料装置

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000335764A (ja) * 1999-05-28 2000-12-05 Canon Inc 画像形成装置

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4878657A (en) * 1986-12-24 1989-11-07 Konica Corporation Sheet conveyance apparatus
US4750018A (en) * 1987-06-26 1988-06-07 Xerox Corporation Pre-transfer copy sheet cleaning apparatus
EP0346934B1 (de) * 1988-06-17 1995-01-25 Canon Kabushiki Kaisha Bildaufzeichnungsgerät
JPH04129940A (ja) * 1990-09-19 1992-04-30 Fuji Xerox Co Ltd 紙粉除去装置
JP2863372B2 (ja) * 1992-05-07 1999-03-03 キヤノン株式会社 プロセスカートリッジ及び画像形成装置
JPH07319357A (ja) * 1994-05-25 1995-12-08 Fuji Xerox Co Ltd 紙粉除去装置
CN1092348C (zh) * 1994-11-08 2002-10-09 佳能株式会社 显影与清洁同时进行的成像方法和成像装置
JPH1039720A (ja) * 1996-07-22 1998-02-13 Ricoh Co Ltd 画像形成装置
JPH11199084A (ja) * 1998-01-06 1999-07-27 Minolta Co Ltd 紙粉除去装置
US6219505B1 (en) * 1998-09-30 2001-04-17 Brother Kogyo Kabushiki Kaisha Image forming apparatus having paper-dust removing devices
NL1010934C2 (nl) * 1998-12-31 2000-07-03 Neopost Bv Inrichting voor het separeren van vellen.

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000335764A (ja) * 1999-05-28 2000-12-05 Canon Inc 画像形成装置

Also Published As

Publication number Publication date
CN1409177A (zh) 2003-04-09
HK1053358A1 (en) 2003-10-17
CN100397246C (zh) 2008-06-25
EP1291729A3 (de) 2003-05-07
EP1291729A2 (de) 2003-03-12

Similar Documents

Publication Publication Date Title
US6708009B2 (en) Image forming device having paper dust removing units
US7680446B2 (en) Cleaning device, process cartridge and image forming apparatus
US6928252B2 (en) Process unit and image forming apparatus having a structure to remove foreign matter
US7954814B2 (en) Feeding device and image forming apparatus
EP1008918A2 (de) Doppelseitigerdrucker und Steuerungsverfahren dafür
US7130096B2 (en) Light beam scanning device and image forming apparatus
EP2075647B1 (de) Bilderzeugungsvorrichtung
US7305207B2 (en) Cleaning system
KR20000005715A (ko) 개선된전사장치,방법및상기전사장치혹은방법을사용하는화상형성장치
US5144385A (en) Curl removing device for an image recorder
EP1291729B1 (de) Bilderzeugungsgerät mit Einheiten zum Entfernen von Papierstaub
JP2509283B2 (ja) 接地装置
US7914215B2 (en) Image forming apparatus
US6129347A (en) Entrance guide for friction/retard feeding systems
EP0778503A2 (de) Elektrophotographische Bilderzeugungsvorrichtung mit positif geladenem Toner
JP3627718B2 (ja) プロセス装置および画像形成装置
JP4203785B2 (ja) 画像形成装置
US7374166B2 (en) Sheet conveying unit, and image reading unit, post-processing unit, and image forming apparatus employing the sheet conveying unit
JP3651380B2 (ja) 画像形成装置
JP2750259B2 (ja) 静電複写プリンティング装置
JP3835318B2 (ja) 画像形成装置
JP4429555B2 (ja) 画像形成装置
JP3750618B2 (ja) 画像形成装置
US9429895B2 (en) Cleaning device and image forming apparatus
JP3624896B2 (ja) プロセス装置および画像形成装置

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

17P Request for examination filed

Effective date: 20031107

AKX Designation fees paid

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

17Q First examination report despatched

Effective date: 20100111

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 617973

Country of ref document: AT

Kind code of ref document: T

Effective date: 20130715

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 60245109

Country of ref document: DE

Effective date: 20130814

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130930

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130920

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 617973

Country of ref document: AT

Kind code of ref document: T

Effective date: 20130619

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130919

REG Reference to a national code

Ref country code: NL

Ref legal event code: VDEP

Effective date: 20130619

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: CY

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130415

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20131021

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CY

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130619

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

26N No opposition filed

Effective date: 20140320

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 60245109

Country of ref document: DE

Effective date: 20140320

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130930

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130910

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130930

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20130619

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130910

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 15

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 16

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20180817

Year of fee payment: 17

Ref country code: DE

Payment date: 20180815

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20180828

Year of fee payment: 17

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 60245109

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20200401

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20190910

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20190930

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20190910