JP2010286519A - Image forming apparatus and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-noise image forming apparatus having high energy efficiency. <P>SOLUTION: The image forming apparatus includes: a secondary transfer roller 61 having a transfer material gripping mechanism 610 gripping transfer material; a transfer material conveying member 250 having a vent hole non-forming area of a first distance in a conveying direction and a vent hole forming area provided with a plurality of vent holes of a second distance different from the first distance; a transfer material conveying device 230 conveying the transfer material released from the transfer material gripping mechanism 610 while sucking the transfer material by the vent hole forming area of the transfer material conveying member; and a control part which controls a circulating position of the transfer material conveying member 250 in the transfer material conveying device 230. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  In the present invention, a latent image formed on a photoreceptor is developed with a liquid developer composed of toner and a carrier, and the resulting developer is further transferred onto a transfer material such as recording paper, and the transfer material is conveyed by a conveyance mechanism. The present invention also relates to an image forming apparatus and an image forming method for forming an image by fusing and fixing a toner image on a medium transferred to a transfer material.

In an image forming apparatus that forms a developed image and transfers the developed image onto a transfer material, various transfer material transport mechanisms for transporting the transfer material are generally incorporated. As such a transfer material transport mechanism, there is known a mechanism in which a transfer material is sucked and held from the back surface where a developed image is not formed by an air flow. As an example of the transfer material transport mechanism, for example, Patent Document 1 (Japanese Patent Laid-Open No. 6-72586) can be cited. This Patent Document 1 discloses an endless conveyance belt that has a large number of air holes and conveys a sheet to a predetermined position, a driving unit that spans the conveyance belt and drives the conveyance belt, and the conveyance belt. And a drive port and a substantially V-shaped suction port having a wide angle toward the predetermined position on the sheet conveyance surface side, and sucks air through the vent hole of the conveyance belt. There is disclosed a paper conveying device characterized by comprising a suction means.
JP-A-6-72586

  In the conventional apparatus described in Patent Document 1, at the timing immediately after the conveying belt starts to suck the paper, the suction means only sucks only a part of the end portion of the paper. Among them, the suction force used for attracting the paper is very small, and most of the suction force is used for sucking air through the ventilation holes of the conveyance belt. Even in such a situation, in order to attract the sheet firmly by the suction means, a suction means having a relatively large suction force must be used. However, the suction means having such a large suction force has a problem that the operation noise is loud, and the noise generated by the image forming apparatus increases due to the leakage of the operation sound to the outside of the apparatus. There is also a problem that a large electric power is required to drive the suction means having a large suction force, and the energy efficiency of the apparatus is deteriorated.

  In order to solve the above-described problems, the image forming apparatus according to the present invention includes a transfer roller having a transfer material gripping portion that grips a transfer material, an airflow forming portion that generates an airflow, and the transfer material. A transfer hole forming region in the transfer direction of the transfer material provided with a vent hole non-formation region in the transfer direction and a transfer hole in which the air flow formed by the air flow forming portion is passed. A transfer material conveying belt that conveys the transfer material transferred by a roller while being sucked by the airflow in the vent hole forming region; and a control unit that controls a rotation position of the transfer material conveying belt. And

  In the image forming apparatus according to the present invention, the control unit controls a speed at which the transfer material conveyance belt rotates.

The image forming apparatus according to the present invention further includes a fixing unit that fixes the transfer material conveyed by the transfer material conveyance belt, wherein the peripheral speed of the transfer roller is v _2T , and the transfer material conveyance belt is rotated. When the moving speed is v and the transfer material conveyance speed of the fixing unit is v _F , the relationship is v _F >v> v _2T .

  The image forming apparatus according to the present invention further includes an image carrier that carries an image and forms a transfer nip by contacting the transfer roller with the transfer material, and the fixing unit includes a first roller. And a second roller that makes contact with the first roller via the transfer material to form a fixing nip, and the transfer material is not simultaneously nipped between the transfer nip and the fixing nip. .

  In the image forming apparatus according to the present invention, the control unit controls a speed of a driving roller that drives the transfer material conveyance belt.

  In the image forming apparatus according to the present invention, the control unit controls the operation of a driving roller that drives the transfer material conveyance belt.

  Further, in the image forming apparatus according to the present invention, the length in the conveyance direction of the transfer material of the air hole non-formation area is the area of the area where the transfer material is sucked and conveyed by the air flow in the air hole formation area. It is longer than the length of the transfer material in the conveyance direction.

  Further, the image forming method according to the present invention is configured such that the transfer material is gripped by the transfer material gripping portion provided in the transfer roller, and the airflow forming portion and the airflow forming portion are formed in the transfer material transport direction. Formation of the vent hole by using a transfer material transport belt having a vent hole forming region in the transport direction of the transfer material in which a vent hole for allowing airflow to pass is disposed, and controlling a rotational position of the transfer material transport belt The transfer material released from the transfer material gripping portion in the region is conveyed while being sucked.

  As described above, according to the image forming apparatus and the image forming method of the present invention, it is not necessary to use a large-sized airflow generating unit that is configured to generate a suction force in the transfer material conveying device, and therefore, it is possible to reduce operation noise. In addition, the sound generated from the image forming apparatus can be suppressed. In addition, according to the image forming apparatus and the image forming method of the present invention, a small-sized apparatus can be used as a structure for generating a suction force, so that an apparatus with high energy efficiency can be configured.

1 is a diagram illustrating main components constituting an image forming apparatus according to an embodiment of the present invention. It is a perspective view of a secondary transfer roller used in the image forming apparatus according to the embodiment of the present invention. It is a figure which shows operation | movement of the transfer material holding | grip mechanism of the secondary transfer roller used with the image forming apparatus which concerns on embodiment of this invention. FIG. 6 is a diagram illustrating an operation of a transfer material transport unit used in the image forming apparatus according to the embodiment of the present invention. FIG. 5 is a diagram illustrating a transfer material conveyance member 250 of a transfer material conveyance device 230 used in an image forming apparatus according to an embodiment of the present invention. FIG. 6 is a diagram illustrating an operation of a transfer material transport unit used in the image forming apparatus according to the embodiment of the present invention. FIG. 6 is a diagram illustrating an operation of a transfer material transport unit used in the image forming apparatus according to the embodiment of the present invention. FIG. 6 is a diagram illustrating an operation of a transfer material transport unit used in the image forming apparatus according to the embodiment of the present invention. FIG. 6 is a diagram illustrating an operation of a transfer material transport unit used in the image forming apparatus according to the embodiment of the present invention. FIG. 2 is a diagram illustrating an outline of a control block in the image forming apparatus according to the embodiment of the present invention. FIG. 4 is a diagram illustrating an example of a control sequence by a control block of the image forming apparatus according to the embodiment of the present invention. FIG. 4 is a diagram illustrating an example of a control sequence by a control block of the image forming apparatus according to the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing main components constituting the image forming apparatus according to the embodiment of the present invention. The developing devices 30Y, 30M, 30C, and 30K are arranged in the lower portion of the image forming apparatus with respect to the image forming units of the respective colors arranged in the central portion of the image forming apparatus, and are transferred to the transfer belt 40, the secondary transfer unit (secondary transfer unit). The configuration of the transfer unit 60, the fixing unit 90, and the like is disposed in the upper part of the image forming apparatus. In particular, since the fixing unit 90 is laid out above the transfer belt 40, the installation area of the entire image forming apparatus can be suppressed. In the present embodiment, a transfer material such as paper that has undergone secondary transfer in the secondary transfer unit 60 is transported to the fixing unit 90 while being sucked by the transfer material transport device 230, the suction devices 210 and 270, and the like. Therefore, such a layout can be realized.

  The developing devices 30Y, 30M, 30C, and 30K are photoconductors 10Y, 10M, 10C, and 10K, corona chargers 11Y, 11M, 11C, and 11K, and exposure units 12Y, 12M, such as an LED array, for forming an image using toner. , 12C, 12K, etc. The photoconductors 10Y, 10M, 10C, and 10K are uniformly charged by the corona chargers 11Y, 11M, 11C, and 11K, and the exposure units 12Y, 12M, 12C, and 12K perform exposure based on the input image signal. Then, electrostatic latent images are formed on the charged photoreceptors 10Y, 10M, 10C, and 10K.

  The developing devices 30Y, 30M, 30C, and 30K generally include liquid developers of respective colors including the developing rollers 20Y, 20M, 20C, and 20K, yellow (Y), magenta (M), cyan (C), and black (K). Developer containers (reservoirs) 31Y, 31M, 31C, 31K to be stored, and application rollers for applying liquid developers of these colors from the developer containers 31Y, 31M, 31C, 31K to the developing rollers 20Y, 20M, 20C, 20K. The anilox rollers 32Y, 32M, 32C, 32K and the like are provided, and the electrostatic latent images formed on the photoreceptors 10Y, 10M, 10C, 10K are developed with the liquid developers of the respective colors.

  The transfer belt 40 is an endless belt, and is stretched around a driving roller 41 and tension rollers 42, 52, and 53. It is rotationally driven by the drive roller 41 while in contact. In the primary transfer portions 50Y, 50M, 50C, and 50K, the primary transfer rollers 51Y, 51M, 51C, and 51K are arranged to face each other with the transfer belt 40 sandwiched between the photoreceptors 10Y, 10M, 10C, and 10K. The developed toner image of each color on the photoreceptors 10Y, 10M, 10C, and 10K is sequentially transferred and transferred onto the transfer belt 40 by using the contact position with 10C and 10K as the transfer position to form a full-color toner image. To do.

  In the secondary transfer unit 60, a secondary transfer roller 61 is disposed opposite to the belt driving roller 41 with the transfer belt 40 interposed therebetween, and a cleaning device including a secondary transfer roller cleaning blade 62 is disposed. Then, at a transfer position where the secondary transfer roller 61 is disposed, transfer of a single-color toner image or a full-color toner image formed on the transfer belt 40 through a transfer material transport path L is performed. Transfer to material.

  Further, a first suction device 210, a transfer material transport device 230, and a second suction device 270 are sequentially arranged downstream of the path transfer material transport path L so as to transport the transfer material to the fixing unit 90. In the fixing unit 90, a single-color toner image or a full-color toner image transferred onto a transfer material such as paper is fused and fixed to the transfer material such as paper.

  The tension roller 42 stretches the transfer belt 40 together with the belt driving roller 41 and the like, and the cleaning device including the transfer belt cleaning blade 49 is brought into contact with the tension roller 42 at a position where the tension roller 42 is stretched. The remaining toner on the transfer belt 40 and the carrier are cleaned.

  The transfer material is supplied to the image forming apparatus by a paper feeding device (not shown). The transfer material set in such a sheet feeding device is sent to the transfer material conveyance path L one by one at a predetermined timing. In the transfer material conveyance path L, the transfer material is conveyed to the secondary transfer position by the gate rollers 101, 101 ′ and the transfer material guide 102, and a single color toner development image or a full color toner development image formed on the transfer belt 40 is obtained. Transfer to transfer material. As described above, the transfer material subjected to the secondary transfer is further conveyed to the fixing unit 90 by the transfer material conveying means centering on the transfer material conveying device 230. The fixing unit 90 includes a heating roller 91 and a pressure roller 92 urged to the heating roller 91 side with a predetermined pressure. A transfer material is inserted between the nips, and the transfer material is placed on the transfer material. The transferred single-color toner image or full-color toner image is fused and fixed to a transfer material such as paper.

  Immediately before the secondary transfer unit 60, a first detection unit 131 composed of a pair of a light emitting element and a light receiving element for detecting a transfer material passing through the transfer material conveyance path L, a heating roller 91 and a pressure roller Immediately after the fixing nip formed at 92, a second detection unit 132 comprising a pair of a light emitting element and a light receiving element that similarly detects the passage of the transfer material is disposed.

  Next, the developing device will be described. Since the configurations of the image forming unit and the developing device for each color are the same, the following description is based on the yellow (Y) image forming unit and the developing device.

  The image forming unit includes a photosensitive member cleaning blade 18Y, a corona charger 11Y, an exposure unit 12Y, a developing roller 20Y of the developing device 30Y, a first photosensitive member squeeze roller 13Y, and a second photosensitive member along the rotation direction of the outer periphery of the photosensitive member 10Y. A photoconductor squeeze roller 13Y ′ is disposed.

  The photoreceptor cleaning blade 18Y that is in contact with the photoreceptor 10Y cleans the liquid developer rich in carrier components on the photoreceptor 10Y.

  A cleaning blade 21Y, an anilox roller 32Y, and a compaction corona generator 22Y are arranged on the outer periphery of the developing roller 20Y in the developing device 30Y. A regulating blade 33Y that adjusts the amount of liquid developer supplied to the developing roller 20Y is in contact with the anilox roller 32Y. An auger 34Y is accommodated in the liquid developer container 31Y. Further, a primary transfer roller 51Y of the primary transfer portion is disposed at a position facing the photoconductor 10Y so as to sandwich the transfer belt 40.

  The photoconductor 10Y is a photoconductor drum made of a cylindrical member having a photosensitive layer such as an amorphous silicon photoconductor formed on the outer peripheral surface, and rotates in the clockwise direction.

The corona charger 11Y is disposed upstream of the nip portion between the photoconductor 10Y and the developing roller 20Y in the rotation direction of the photoconductor 10Y, and a voltage is applied from a power supply device (not shown).
0Y is corona charged. The exposure unit 12Y irradiates light onto the photoconductor 10Y charged by the corona charger 11Y downstream of the corona charger 11Y in the rotation direction of the photoconductor 10Y, thereby forming a latent image on the photoconductor 10Y. Note that, from the beginning to the end of the image forming process, the configuration of the rollers and the like arranged in the preceding stage is defined to be upstream from the configuration of the rollers and the like arranged in the subsequent stage.

  The developing device 30Y includes a compaction corona generator 22Y that performs a compaction action, and a developer container 31Y that stores a liquid developer in a state where toner is dispersed in a carrier at a weight ratio of approximately 20%.

  Further, the developing device 30Y includes a developing roller 20Y that carries the liquid developer, an anilox roller 32Y that is a coating roller for applying the liquid developer to the developing roller 20Y, and a liquid developer amount that is applied to the developing roller 20Y. A regulating blade 33Y for regulating, an auger 34Y for feeding the liquid developer to the aniloc roller 32Y while stirring and transporting the liquid developer, a compaction corona generator 22Y for bringing the liquid developer carried on the developing roller 20Y into a compacted state, and a developing roller 20Y A developing roller cleaning blade 21Y that performs the above cleaning.

  The liquid developer contained in the developer container 31Y is a low-concentration (about 1 to 3 wt%) and low-viscosity volatile at room temperature using a conventionally used Isopar (trademark: exon) as a carrier. Is a non-volatile liquid developer having a high concentration and high viscosity and having non-volatility at room temperature. That is, in the liquid developer in the present invention, a solid having an average particle diameter of 1 μm in which a colorant such as a pigment is dispersed in a thermoplastic resin is introduced into a liquid solvent such as an organic solvent, silicon oil, mineral oil, or edible oil. High viscosity (HAAKE RheoStress RS600, which is added together with a dispersant and has a toner solid content concentration of about 15 to 25%, and has a viscoelasticity of 30 to 30 at a shear rate of 1000 (1 / s) at 25 ° C. (About 300 mPa · s).

  The anilox roller 32Y functions as an application roller that supplies and applies a liquid developer to the developing roller 20Y. The anilox roller 32Y is a cylindrical member, and is a roller having a concave and convex surface formed by grooves engraved in a fine and uniform spiral shape on the surface so as to easily carry a developer on the surface. The anilox roller 32Y supplies the liquid developer from the developer container 31Y to the developing roller 20Y. During operation of the apparatus, as shown in FIG. 1, the auger 34Y rotates counterclockwise to supply the liquid developer to the aniloc roller 32Y, and the aniloc roller 32Y rotates counterclockwise to develop the developing roller 20Y. A liquid developer is applied to the substrate.

  The regulating blade 33Y is an elastic blade having a surface covered with an elastic body, and includes a rubber portion made of urethane rubber or the like that comes into contact with the surface of the anilox roller 32Y. Then, the film thickness and amount of the liquid developer carried and conveyed by the anilox roller 32Y are regulated and adjusted, and the amount of the liquid developer supplied to the developing roller 20Y is adjusted.

  The developing roller cleaning blade 21Y is made of rubber or the like that contacts the surface of the developing roller 20Y. The developing roller 20Y is disposed downstream of the developing nip portion where the developing roller 20Y contacts the photoreceptor 10Y in the rotation direction of the developing roller 20Y. The liquid developer remaining on the roller 20Y is scraped off and removed.

The compaction corona generator 22Y is an electric field applying means for increasing the charging bias on the surface of the developing roller 20Y. An electric field is applied from the compaction corona generator 22Y to the developing roller 20Y at the compaction site by the compaction corona generator 22Y. The The electric field applying means for compaction may use a compaction roller or the like instead of the corona discharge of the corona discharger shown in FIG.

  The developer carried on the developing roller 20Y and compacted is developed corresponding to the latent image on the photoconductor 10Y by applying a predetermined electric field at the developing nip portion where the developing roller 20Y contacts the photoconductor 10Y.

  The developer remaining after development is scraped off and removed by the developing roller cleaning blade 21Y and dropped into the collecting section in the developer container 31Y to be reused. The carrier and toner that are reused in this way are not in a mixed color state.

  The photosensitive member squeeze device disposed upstream of the primary transfer is disposed downstream of the developing roller 20Y so as to face the photosensitive member 10Y, and collects excess carrier of the toner image developed on the photosensitive member 10Y. is there. This photoconductor squeeze device is composed of a first photoconductor squeeze roller 13Y and a second photoconductor squeeze roller 13Y ′ made of an elastic roller member that slides in contact with the photoconductor 10Y, and is developed on the photoconductor 10Y. It has a function of collecting excess carrier and originally unnecessary fog toner from the toner image and increasing the toner particle ratio in the visible image (toner image). A predetermined bias voltage is applied to the photoconductor squeeze rollers 13Y and 13Y '.

  The surface of the photoreceptor 10Y that has passed through the squeeze device including the first photoreceptor squeeze roller 13Y and the second photoreceptor squeeze roller 13Y 'enters the primary transfer unit 50Y.

  In the primary transfer portion 50Y, the developer image developed on the photoreceptor 10Y is transferred to the transfer belt 40 by the primary transfer roller 51Y. In the primary transfer portion, the toner image on the photoconductor 10 is transferred to the transfer belt 40 side by the action of the transfer bias applied to the primary transfer backup roller 51. Here, the photoconductor 10Y and the transfer belt 40 are configured to move at a constant speed, and the driving load of rotation and movement is reduced, and the disturbance effect on the visible toner image of the photoconductor 10Y is suppressed.

  In the developing devices 30M, 30C, and 30K, magenta (M), cyan (C), and black (K) toners are respectively formed on the photoreceptors 10M, 10C, and 10K by a process similar to the developing process of the developing device 30Y. Each image is formed. The transfer belt 40 passes through the nip of the primary transfer portion 50 for each color of yellow (Y), magenta (M), cyan (C), and black (K), and a developer (development image) on the photoreceptor of each color. Are transferred, color-superposed, and enter the nip portion of the secondary transfer unit 60.

  The transfer belt 40 that has passed through the secondary transfer unit 60 circulates again to receive the transfer image at the primary transfer unit 50, but on the upstream side where the primary transfer unit 50 is executed, the transfer belt 40 is a transfer belt cleaning blade. 49 or the like is performed for cleaning.

  The transfer belt 40 has a three-layer structure in which an elastic intermediate layer of polyurethane is provided on a polyimide base layer, and a PFA surface layer is provided thereon. Such a transfer belt 40 is stretched on the polyimide base layer side by a driving roller 41 and tension rollers 42, 52 and 53, and is used so that a toner image is transferred on the PFA surface layer side. Since the transfer belt 40 having elasticity formed in this way has good followability and responsiveness to the surface of the transfer material, toner particles having a particularly small particle diameter are transferred to the recesses of the transfer material during the secondary transfer. It is effective for sending and transferring.

Next, the secondary transfer roller 61 used in the image forming apparatus according to the present embodiment will be described in more detail. FIG. 2 is a perspective view of a secondary transfer roller used in the image forming apparatus according to the embodiment of the present invention, and FIG. 3 is a drawing of a transfer material of the secondary transfer roller used in the image forming apparatus according to the embodiment of the present invention. It is a figure which shows operation | movement of a mechanism. 2 and 3, reference numeral 601 denotes a roller body, 602 denotes a roller shaft portion, 605 denotes an opening recess, 607 denotes an elastic member, 610 denotes a transfer material gripping mechanism, 611 denotes a transfer material gripping portion, and 612 denotes a transfer material gripping portion receiver. Reference numeral 640 denotes a transfer material peeling member.

  Roller shaft portions 602 are provided at both ends of the roller body portion 601 of the secondary transfer roller 61, and are attached to the apparatus main body side so as to be rotatable around the roller shaft portion 602. The roller body 601 is provided with an opening recess 605 extending in the axial direction. The transfer material gripping mechanism 610 is provided in the opening recess 605, and the elastic member 607 is provided in the roller body 601 other than the opening recess 605. Is provided. The transfer material gripping mechanism 610 is a mechanism for gripping or releasing the transfer material. The elastic member 607 is composed of a semiconductive elastic rubber layer having an electrical resistance component, and passes through the secondary transfer nip in the secondary transfer unit in a state where a transfer material is wound around the elastic member 607. In this case, the toner image is transferred from the transfer belt 40 to the transfer material.

  In general, the transfer material gripping mechanism 610 is appropriately arranged between a plurality of pairs of transfer material gripping portions 611 and transfer material gripping portion receiving portions 612 provided discretely in the roller axial direction, and between the pairs in the roller axial direction. And a plurality of transfer material peeling members 640 that are formed. All the transfer material gripping portions 611 are configured to be movable, and operate to clamp the transfer material with the transfer material gripping portion receiving portion 612 to grip the transfer material, or to receive the transfer material gripping portion. The transfer material can be released by operating so as to be spaced from the portion 612. All the transfer material peeling members 640 operate so as to push out the transfer material held by the transfer material holding portion 611 and the transfer material holding portion receiving portion 612 in a direction away from the secondary transfer roller 61 side.

  The operation of the transfer material gripping mechanism 610 will be described in more detail with reference to FIG. FIG. 3 is a diagram showing each configuration of the transfer material gripping mechanism 610 schematically shown from the axial direction. Each state of the transfer material gripping mechanism 610 shown in FIGS. 3A, 3B, 3C, and 3D is applied to the secondary transfer roller 61 of FIG. 6 schematically shows an operation state that the transfer material gripping mechanism 610 takes when the transfer material gripping mechanism 610 of the secondary transfer roller 61 comes to the position marked as C or D. FIG.

  FIG. 3A shows a state where the secondary transfer roller 61 is rotating without gripping the transfer material by the transfer material gripping mechanism 610. At this time, the transfer material gripping portion 611 and the transfer material peeling member 640 are configured to fit within the outermost periphery when the secondary transfer roller 61 is viewed as a cylinder. This shows a state when the transfer material gripping mechanism 610 exists in the range of A in FIG. 1 during the rotation process of the secondary transfer roller 61.

  In FIG. 3B, the transfer material gripping portion 611 moves in the direction (a), a predetermined space is formed between the transfer material gripping portion receiving portion 612, and the transfer material S entering the space is transferred. FIG. 10 is a diagram showing a state where preparation is made to be held between a material gripping portion 611 and a transfer material gripping portion receiving portion 612. In the rotation process of the secondary transfer roller 61, the transfer material gripping mechanism 610 comes to the position B in FIG. 1 and enters along the transfer material guide 102 along with the rotation of the gate rollers 101 and 101 ′. The state which is preparing the holding | grip of a transfer material is shown.

FIG. 3C shows a state in which the transfer material S that has entered the space is sandwiched between the transfer material gripping portion 611 moved in the (a ′) direction and the transfer material gripping portion receiving portion 612. Yes. At this time, the transfer material S held at one end by the transfer material gripping mechanism 610 is wound around the roller body 601 of the secondary transfer roller 61 as the secondary transfer roller 61 rotates. Thus, since the transfer material S is held and fixed by the transfer material gripping mechanism 610 before the transfer material enters the secondary transfer nip, the transfer material S to which the toner image is transferred can be positioned accurately. . In the rotation process of the secondary transfer roller 61, when the transfer material gripping mechanism 610 is positioned in the range C in FIG. 1, the state shown in FIG. 3C is maintained.

  In FIG. 3D, the transfer material gripping portion 611 moves in the direction (a) to form a predetermined space between the transfer material gripping portion receiving portion 612 and release the transfer material S, and the transfer material peeling member 640. Shows a state in which the transfer material S is pushed in the direction away from the secondary transfer roller 61 by moving in the (b) direction. In such an operation state, in the rotation process of the secondary transfer roller 61, the transfer material gripping mechanism 610 comes to the position D in FIG. 1, and the transfer material S on which the toner image has been transferred through the secondary transfer nip, This is when handing over to the next transfer material conveyance process.

  As described above, the transfer material gripping mechanism 610 grips the transfer material S before the transfer material S is inserted between the secondary transfer nips of the transfer belt 40 and the secondary transfer roller 61, and The operation is to release the gripped transfer material S after being inserted between the secondary transfer nips with the transfer roller 61. The transfer material S that has passed through the secondary transfer nip reliably separates the transfer material S from the secondary transfer roller 61 when the transfer material gripping mechanism 610 operates as shown in FIG. It can be reliably guided to the material transport process. In general, in an image forming process using a liquid developer, the transfer material S on which the toner image is transferred at the secondary transfer nip is attached to either the secondary transfer roller 61 or the transfer belt 40. Although the peeling may be difficult, the transfer material S can be reliably peeled from each component by the operation of FIG. 3D by the transfer material gripping mechanism 610.

  The transfer material S released by the transfer material gripping mechanism 610 as described above is then transported to the transfer unit 90. The transport means for performing this transport will be described next. FIG. 4 is a diagram for explaining the operation of the transfer material conveying means used in the image forming apparatus according to the embodiment of the present invention, and FIG. 5 is a transfer material conveying device 230 used in the image forming apparatus according to the embodiment of the present invention. FIG. 6 is a view for explaining a transfer material conveying member 250. 6 to 9 are diagrams for explaining the operation of the transfer material transport unit used in the image forming apparatus according to the embodiment of the present invention.

  4 to 9, 133 is a belt position detection unit, 135 is a drive motor, 139 is a detection claw piece, 210 is a first suction device, 211 is a housing unit, 212 is a suction surface, 215 is an air flow generation unit, 230 is a transfer material conveyance device, 231 is a casing, 232 is a suction surface, 233 is a partition member, 235 is an air flow generation unit, 250 is a transfer material conveyance member, 251 is a transfer material conveyance member driving roller, and 252 and 253 are transfer Material conveying member stretching roller, 270 is a second suction device, 271 is a housing portion, 272 is a suction surface, 275 is an airflow generating portion, 400 is a blower device, 401 is a housing portion, 402 is an opening portion, and 405 is an airflow Each generation part is shown.

  The first suction device 210 has a casing 211 to which an airflow generation unit 215 such as a sirocco fan is attached. The exhaust can be performed. The lower surface side of the housing 211 is a suction surface 212 having a plurality of ventilation holes on one surface. The first suction device 210 operates the air flow generation unit 215 to perform exhaust as shown by a outside the housing unit 211 to generate a suction force as shown by A. By this suction force, the transfer material S onto which the toner image has been transferred is held on the suction surface 212 against gravity. The suction force is such that the transfer material S is held on the suction surface 212, but the transfer material S is prevented from advancing against the force by which the transfer material S is pushed out from the secondary transfer nip. is not.

The transfer material transport device 230 is generally configured by a housing portion 231 to which an airflow generating portion 235 such as a sirocco fan is attached, a transfer material transport member 250 disposed around the housing portion 231, and the like. In the transfer material transport device 230, the airflow generation unit 235 can exhaust air from the space R <b> 2 in the housing unit 231 to the outside of the housing unit 231.

  The lower surface side of the housing portion 231 is a suction surface 232 having a plurality of air holes provided on one surface. Along with the exhaust operation b of the airflow generation portion 235, the suction surface 232 has a suction force as shown at B. appear. At this time, due to the action of the partition wall member 233 provided in the housing part 231, the air is discharged relatively uniformly from the space R2 in the housing part 231, and the suction force on the suction surface 232 is also biased depending on the location. It does not occur.

  The transfer material conveying member 250 disposed around the casing 231 is an endless belt provided with a plurality of through holes (not shown) penetrating in a part of the region, and a driving force is applied to the transfer material conveying member 250. The transfer material conveying member driving roller 251 to be applied and the transfer material conveying member stretching rollers 252 and 253 are stretched. The transfer material conveying member 250 moves in the direction of the arrow in the figure as the transfer material conveying member driving roller 251 driven by the drive motor 135 rotates. This moving speed is determined by the image forming process (transfer of the two transfer units 60). The speed is about 1.1 times the speed. The axial length of the transfer material conveyance member 250 (the width of the transfer material conveyance member 250) is configured to be longer than the width of the transfer material having the maximum width that can be handled by the image forming apparatus.

  Here, with reference to FIG. 5, the transfer material conveyance member 250 in the transfer material conveyance device 230 will be described in more detail. The transfer material conveying member 250 is stretched in a direction perpendicular to the roller axis direction of the transfer material conveying member drive roller 251 and the transfer material conveying member stretching rollers 252 and 253, and the rotation direction is conveyed. It can be defined as a direction.

  The transfer material conveying member 250 has two characteristic areas in this conveying direction. One of them is a vent hole forming region Bh in which a vent hole penetrating from one main surface to another main surface is formed, and this region has a length Lh (first distance) in the transport direction. . The other is a vent hole non-formation region Bn in which no through vent is formed as described above, and this region has a conveyance direction length Ln (second distance). In the present embodiment, such a ventilation hole non-formation region Bn of the transfer material conveying member 250 covers the suction surface 232 of the housing portion 231, so that the transfer material S is efficiently sucked by the ventilation hole formation region Bh. I can do it. In order to cover the suction surface 232 of the housing portion 231, the conveyance direction length Ln (second distance) is set to be longer than the conveyance direction length of the suction surface 232 of the transfer material conveyance device 230. ing.

  When viewed from the conveying direction of the transfer material conveying member 250, the front end of the air hole non-forming region Bn is Bo and the rear end is Be. A detection claw 139 is provided at the tip Bo of the air hole non-formation region Bn of the transfer material conveying member 250, and the belt position detection unit 133 consisting of a pair of a light emitting element and a light receiving element serves as the detection claw piece. By detecting the passage of 139, the circulation state (circulation position) of the transfer material conveying member 250 can be grasped.

  Moreover, it can be defined as follows. The vent holes are formed in the conveying direction of the transfer material conveying member 250 at the first interval in the vent hole forming region Bh, and the non-venting region Bn in which the vent holes are formed in the second interval. . When there are a plurality of inter-hole distances, the part with the longest interval becomes the second interval, which becomes the vent hole non-forming region Bn.

When the air hole forming area Bh of the transfer material conveying member 250 exists below the suction surface 232, the suction force on the suction surface 232 acts from the air holes of the transfer material conveying member 250, so that the toner image is transferred. The transfer material S is held on the transport surface P of the transfer material transport member 250 against gravity, and is transported on the transport surface P as the transfer material transport member 250 is moved by the driving force of the transfer material transport member driving roller 251. Will be. An area between the transfer material conveyance member stretching roller 252 and the transfer material conveyance member driving roller 251 of the transfer material conveyance member 250 is used as a conveyance surface P for conveying the transfer material S.

  The second suction device 270 includes a housing part 271 to which an airflow generation unit 275 such as a sirocco fan is attached. By this airflow generation unit 275, the outside of the housing part 271 is separated from the space R3 in the housing part 271. To exhaust. The lower surface side of the housing portion 271 is a suction surface 272 having a plurality of air holes provided on one surface, and a suction force as shown in C is obtained by the exhaust operation c of the air flow generation unit 275 of the second suction device 270. Can be generated. With this suction force, the transfer material S onto which the toner image has been transferred is held on the suction surface 272 against gravity. This suction force is such that the transfer material S is held on the suction surface 272, but is not so great as to prevent the transfer material S from being conveyed against the force accompanying the transfer material S being conveyed.

  The transfer material conveying means according to this embodiment including the first suction device 210, the transfer material conveying device 230, the second suction device 270, etc. conveys the transfer material with the surface of the transfer material onto which the toner image is transferred being vertically downward. To do.

  The blower 400 is for discharging air into the space between the transfer belt 40 and the secondary transfer roller 61 near the outlet of the secondary transfer nip. Air is sent into a space R4 in 401. The casing 401 is provided with an opening 402 extending in the axial direction of the rollers, and the air sent into the casing 401 due to the airflow generation operation d of the airflow generator 405 is the opening 402. To D as shown in FIG. The air ejection force at this time is adjusted so that the transfer material S on which the toner image is transferred does not sag against gravity and the transfer material S does not flutter with the air.

Next, the operation of the transfer material transport unit in the present embodiment configured as described above will be described. FIG. 4 shows the state immediately after the leading end ( _SO ) of the transfer material S in the transport direction is discharged from the secondary transfer nip of the secondary transfer unit 60, that is, from the secondary transfer unit 60 side toward the transport means. The state immediately after delivery is shown. As shown in the figure, the transfer material S is held on the suction surface 212 without falling by the suction force A of the suction surface 212 generated in accordance with the operation a of the air flow generation unit 215, while falling from the secondary transfer unit 60 side. It is conveyed so as to slide on the suction surface 212 by the force of the feeding operation. In this case, the surface of the transfer material S attracted by the suction surface 212 is the surface on which the toner image is not formed by the immediately preceding secondary transfer operation. There will be no disturbance. Further, in the present embodiment, by providing the first suction device 210, the discharge posture of the transfer material S can be stably maintained, and as a result, the toner image forming surface of the transfer material S is downward in the gravity direction. It is possible to prevent an unfixed toner image from being disturbed by touching a member such as a transfer belt 40. In addition, since the first suction device 210 that sucks the transfer material S is provided between the secondary transfer roller 61 and the transfer material transport device 230, the posture of the transfer material after the front end of the transfer material is separated from the belt or the transfer roller 61. Can follow the air suction, and the posture of the transfer material can be stabilized.

  At this time, the timing control is performed so that the air hole non-forming region Bn that is the region from the front end Bo to the rear end Be of the transfer material transport member 250 in the transfer material transport device 230 is arranged on the lower surface of the suction surface 232. Has been. Therefore, in the state shown in FIG. 4, the suction force B at the lower part of the transfer material conveying device 230 is cut off. At this time, the transfer material conveyance member driving roller 251 of the transfer material conveyance device 230 is stopped, and the transfer material conveyance member 250 is also kept stopped.

The suction surface 2 of the first suction device 210 receives the force of the feeding operation from the secondary transfer unit 60 side.
When the leading end of the transfer material S transported while sliding on the sheet 12 reaches the transfer material transport device 230 side, the state shown in FIG. 6 is obtained.

FIG. 6 shows a state in which the leading end portion (S _O ) of the transfer material S in the conveyance direction is approaching the lower surface portion of the transfer material conveyance device 230. At this time, rotation of the transfer material conveyance member drive roller 251 of the transfer material conveyance device 230 is started, and the air hole formation region Bh immediately after Be in the transfer material conveyance member 250 (as viewed from the conveyance direction) is formed on the suction surface 232. The suction force B of the transfer material transport device 230 acts on the lower surface from the air hole forming region Bh. The leading end portion (S _O ) of the transfer material S in the conveyance direction reaches the lower surface of the suction force B action region, and the transfer material S is transferred to the transfer material conveyance device 2.
By being sucked and held by the transfer member 30, the transfer material is conveyed along with the circular movement of the transfer material conveying member 250. At this time, most of the area on the lower surface of the suction surface 232 is covered by the air hole non-formation area Bn of the transfer material conveying member 250. For this reason, the suction force generated by the airflow generation unit 235 is effectively used to attract the transfer material S. For this reason, it is not necessary to use an air flow generation unit 235 that generates a large suction force, and it is possible to suppress the operation sound of the air flow generation unit 235 and to limit the sound generated by the image forming apparatus. Become.

FIG. 7 shows a state in which the leading end portion (S _O ) of the transfer material S in the conveyance direction passes through the region where the suction surface 232 of the transfer material conveyance device 230 is formed and is directed toward the second suction device 270. . At this time, in the state shown in FIG. 7, the air hole forming region Bh of the transfer material transport member 250 covers the entire suction surface 232, and the suction force B is applied to the entire lower surface of the transfer material transport device 230. Has come to work. Note that, during the transition from FIG. 6 to FIG. 7, the detection claw piece 139 provided at the front end Bo of the air hole non-forming region Bn of the transfer material transport member 250 passes through the belt position detection unit 133. The rotation position of the transfer material conveying member 250 can be grasped on the apparatus side.

Further, the state shown in FIG. 7 shows a state immediately after the trailing end (S _E ) in the transport direction of the transfer material S is discharged from the secondary transfer nip of the secondary transfer unit 60. In particular, at this time, by operating the air blower 400 to discharge air as indicated by D, the rear end portion of the transfer material S when the rear end portion (S _E ) of the transfer material S is discharged from the secondary transfer nip. It is possible to prevent (S _E ) from touching the transfer belt 40 and the like so that the image is soiled.

In this embodiment, since the blower 400 that discharges air into the nip exit space between the secondary transfer roller 61 and the transfer belt 40 is provided as described above, the transfer material trailing edge (S _E ) is 2.
Even after being discharged from the secondary transfer nip, it can be pressed against the secondary transfer roller 61 side, and the posture of the transfer material S after the secondary transfer nip is discharged can be stabilized.

Next, the rear end portion (S _E ) of the transfer material S in the transport direction is held by the suction force B on the transport surface P of the transfer material transport member 250 and moves along the transport surface P as the transfer material transport member 250 moves. The process proceeds toward the fixing unit 90.

In FIG. 8, the transfer material S conveyance direction leading end (S _O ) passes through the fixing nip of the fixing unit 90, and the transfer material S conveyance direction rear end (S _E ) is the bottom surface of the transfer material conveyance device 230. It shows the state of approaching. In such a state, the second detection unit 132 is in a state of detecting the leading end portion (S _O ) of the transfer material S in the transport direction.

Further, the timing control is performed so that the air hole non-formation region Bn of the transfer material transport member 250 comes immediately after the rear end portion (S _E ) of the transfer material S transported by the transfer material transport device 230. Yes. In the region where the transfer material S does not exist on the transfer material conveying member 250, the air hole non-forming region Bn serves as a cover for the suction surface 232 so that the suction force generated by the airflow generation unit 235 is not wasted. It has become.

FIG. 9 shows a state immediately after the rear end portion (S _E ) of the transfer material S in the conveyance direction passes through the region where the suction surface 232 of the transfer material conveyance device 230 is formed. In this state, the air hole non-forming region Bn, which is the region from the front end Bo to the rear end Be of the transfer material transport member 250, is arranged on the lower surface of the suction surface 232 and then transferred by the transfer material transport device 230. The material conveying member driving roller 251 is stopped, and the transfer material conveying member 250 is also stopped. In the state shown in FIG. 9, the suction force B below the transfer material transport device 230 is completely blocked.

  According to the above configuration, it is not necessary to use a large fan for the airflow generation unit 235 that generates a suction force in the transfer material transport device 230, so that it is possible to reduce operation noise and image formation. It is also possible to suppress sound emitted from the device. In addition, according to the image forming apparatus and the image forming method of the present invention, since a small-sized airflow generation unit 235 that generates a suction force can be used, an apparatus with high energy efficiency can be configured.

  The transfer material S shown in FIGS. 4 and 6 to 9 is the longest transfer material that can be handled by the image forming apparatus when viewed from the transfer material conveyance direction. In the image forming apparatus of the present invention, even when the longest transfer material is used, the transfer material S is not sandwiched between the fixing nip of the fixing unit 90 and the secondary transfer nip of the secondary transfer unit 60. As described above, the dimensions of each component are determined. For this reason, even if there is a difference in the speed at which the transfer material S is transported between the fixing unit 90 and the secondary transfer unit 60, the transfer material S does not sag or pull, and the image or the like can be obtained. It is possible to avoid the adverse effects of.

  Further, when the transfer material S is being transported on the transport surface P of the transfer material transport device 230 while being sandwiched between the secondary transfer nips of the secondary transfer unit 60, the transport speed of the secondary transfer unit 60 is Even if there is a difference between the transfer speed of the transfer material transport member 250, the transfer material S held by the transfer material transport member 250 is held only by the suction force of air, so that the transfer material transport Since the member 250 can be slid, the transfer material S does not sag or pull.

  Similarly, when the transfer material S is being transported on the transport surface P of the transfer material transport device 230 while being sandwiched between the fixing nips of the fixing unit 90, the transport speed of the fixing unit 90 and the transfer material transport member Even if there is a difference between the conveyance speed of 250, the transfer material can be slid on the transfer material conveyance member 250, and the transfer material S is not slacked or pulled.

  As described above, the transfer material conveyance device 230 can function as a mechanism that absorbs the difference in the conveyance speed of the transfer material S in each unit.

In this embodiment, the circumferential speed of the secondary transfer roller 61 (same as the secondary transfer process speed) is v _2T , the circumferential speed of the transfer material conveying member 250 is v, and the fixing speed in the fixing unit 90 is v. when the _F, v _F> v> v has been set to have a relation of _2T, the transfer material S, at the same time both the secondary transfer nip of the fixing nip and the secondary transfer unit 60 of the fixing unit 90 Since no pinching occurs, there is no influence on the transfer material S even if there is a speed difference as described above. Note that the relationship of v _F >v> v _2T in the present embodiment will be described in more detail: v = 1.1 × v _2T and v _F = 1.1 × v.

The transfer material S transported on the transport surface P of the transfer material transport device 230 passes through the suction surface 272 of the second suction device 270 and passes between the fixing nip formed by the heating roller 91 and the pressure roller 92 in the fixing unit 90. Enter. The transfer material S that has passed through the fixing nip is fused with a toner image to become a permanent visible image.

  In the image forming method using the liquid developer, a phenomenon occurs in which the fixing unit 90 can obtain a good fixing efficiency if a predetermined time after the secondary transfer in the secondary transfer unit 60 is set. There is. This is because the carrier that has inhibited fixing can penetrate into the transfer material when the predetermined time has elapsed. If the layout in which the fixing unit 90 is provided immediately after the secondary transfer unit 60 is taken, the transfer material S is subjected to toner transfer by the secondary transfer unit 60 and is fixed soon, and there is a concern that fixing efficiency is lowered. However, the image forming apparatus according to the present invention includes the first suction device 210, the transfer material transport device 230, the second suction device 270, and the like between the secondary transfer unit 60 and the fixing unit 90. Therefore, the fixing unit 90 can obtain a good fixing efficiency because a predetermined time until the fixing after the secondary transfer is performed can be obtained depending on the time required for transporting the transfer material S. be able to.

  Further, according to the image forming apparatus of the present invention, since the first suction device 210 that sucks the transfer material S discharged from the secondary transfer unit 60 is provided, the transfer material S after the secondary transfer is transferred. Since the sheet can be discharged into the space above the belt 40 and the fixing unit 90 can be arranged using the space, there is an effect that the installation surface of the apparatus can be reduced.

  Next, control of the image forming apparatus according to the present invention configured as described above will be described. FIG. 10 is a diagram showing an outline of a control block in the image forming apparatus according to the embodiment of the present invention. In FIG. 10, 131 is a first detector, 132 is a second detector, 133 is a belt position detector, 134 is a motor controller, 135 is a drive motor, and 150 is a main controller.

  The main control unit 150 is a main controller for performing each control of the image forming apparatus according to the present invention. As such a main control unit 150, a general-purpose information processing apparatus including a CPU, a RAM, a ROM, and the like is used, and a program for causing the CPU to execute an operation of outputting a command to a predetermined block based on input predetermined information Can be realized by storing in advance in the ROM. The main control unit 150 receives signals from the first detection unit 131, the second detection unit 132, and the belt position detection unit 133, executes a predetermined calculation, and sends a command signal to the motor controller 134 according to the calculation result. It is supposed to be sent out. Upon receiving a command signal from the main controller 150, the motor controller 134 can perform on / off control such as rotation and stop of the drive motor 135, speed control, and the like.

  The first detection unit 131 is provided immediately before the secondary transfer unit 60 in the transfer material conveyance path L, and detects the passage of the transfer material S passing through the transfer material conveyance path L. The first detection unit 131 sends an on signal to the main control unit 150 when the transfer material S is detected, and sends an off signal to the main control unit 150 when the transfer material S is not detected.

  The second detection unit 132 is provided immediately after the fixing unit 90 in the transfer material conveyance path L, and detects the passage of the transfer material S passing through the transfer material conveyance path L. The second detection unit 132 sends an on signal to the main control unit 150 when the transfer material S is detected, and sends an off signal to the main control unit 150 when the transfer material S is not detected.

  The belt position detection unit 133 detects the passage of the detection claw piece 139 provided on the transfer material conveyance member 250 and transmits it to the main control unit 150. The main control unit 150 can obtain the rotation position information of the transfer material conveyance member 250 in the transfer material conveyance device 230 based on the detection signal from the belt position detection unit 133.

  Next, an example of control by the control block configured as described above will be described. FIG. 11 is a diagram showing an example of a control sequence by the control block of the image forming apparatus according to the embodiment of the present invention.

  In FIG. 11, the first level is the detection signal of the first detection unit 131, the second level is the detection signal of the second detection unit 132, the third level is the detection signal of the belt position detection unit 133, and the fourth The stages indicate the speed control status of the drive motor 135, respectively. Note that the initial state of the transfer material conveying member 250 in the transfer material conveying device 230 is assumed to be the state shown in FIG.

When the first detection unit 131 arranged in the transfer material conveyance path L upstream from the secondary transfer unit 60 detects the transfer material S conveyance direction front end (S _O ), the main control unit 150 performs this timing. Based on the above, the timing for starting driving the drive motor 135 at the first speed (v) is measured. More specifically, the timing at which the leading end portion (S _O ) of the transfer material S in the conveyance direction reaches the lower part of the suction surface 232 of the transfer material conveyance device 230 is calculated, and based on this, as shown in FIG. Is started at the first speed (v).

Next, when the first detection unit 131 detects the rear end portion (S _E ) of the transfer material S in the transport direction, the main control unit 150 stores this timing in memory. Further, when the belt position detection unit 133 detects the detection claw piece 139 provided at the leading end Bo of the ventilation hole non-forming region Bn of the transfer material transport member 250, the rear end portion (S _{E of the} transfer material S in the transport direction). ) And the tip portion Bo of the vent hole non-forming region Bn are calculated, the adjustment speed is calculated based on this, and the drive motor 135 is stopped after a predetermined time.

By controlling in the sequence as described above, the suction surface 232 is not formed with a vent hole before the transfer material S conveyance direction front end (S _O ) reaches the lower portion of the suction surface 232 of the transfer material conveyance device 230. The state is covered with the region Bn. Similarly, after the rear end (S _E ) in the transport direction is removed from the lower portion of the suction surface 232, the suction surface 232 is similarly covered with the air hole non-forming region Bn.

Next, another example of control by the control block will be described. FIG. 12 is a diagram showing another example of the control sequence by the control block of the image forming apparatus according to the embodiment of the present invention. The difference from the previous example is that the drive motor 135 is only controlled to be turned on and off in the case shown in FIG. 12, and the other points are the same. In the control example of FIG. 12, based on the detection of the detection claw piece 139 provided at the front end Bo of the air hole non-forming region Bn, the transfer material S conveyance direction rear end (S _E ) Adjustment is made with the stop time of the drive motor 135 so that the tip end Bo of the formation region Bn substantially coincides. Even in such a control, the suction surface 232 is vented before the leading end (S _O ) of the transfer material S in the transport direction reaches the lower portion of the suction surface 232 of the transfer material transport device 230 as in the previous example. Even after the rear end (S _E ) in the transport direction is removed from the lower portion of the suction surface 232, the suction surface 232 is covered with the air hole non-forming region Bn.

  As described above, according to the image forming apparatus and the image forming method of the present invention, it is not necessary to use a large-sized airflow generating unit that is configured to generate a suction force in the transfer material conveying device, and therefore, it is possible to reduce operation noise. In addition, the sound generated from the image forming apparatus can be suppressed. In addition, according to the image forming apparatus and the image forming method of the present invention, a small-sized apparatus can be used as a structure for generating a suction force, so that an apparatus with high energy efficiency can be configured.

10Y, 10M, 10C, 10K ... photoreceptor, 11Y, 11M, 11C, 11K ... corona charger, 12Y, 12M, 12C, 12K ... exposure unit, 13Y, 13M, 13C, 13K ... First photosensitive member squeeze roller, 13Y ′, 13M ′, 13C ′, 13K ′... Second photosensitive member squeeze roller, 14Y, 14Y ′, 14M, 14M ′, 14C, 14C ′, 14K, 14K ′,. Photoconductor squeeze roller cleaning blade, 18Y, 18M, 18C, 18K ... Photoconductor cleaning blade, 20Y, 20M, 20C, 20K ... Developing roller, 21Y, 21M, 21C, 21K ... Developing roller cleaning blade , 22Y, 22M, 22C, 22K ... compaction corona generator, 30Y, 3 M, 30C, 30K ... developing apparatus, 31Y, 31M, 31C, 31K ... developer container, 32Y, 32M, 32C, 32K ... anilox roller, 31Y, 31M, 31C, 31K ... developer Container, 33Y, 33M, 33C, 33K ... Regulating blade, 34Y, 34M, 34C, 34K ... Auger (supply roller), 40 ... Transfer belt, 41 ... Belt drive roller, 42 ... Tension roller, 45 ... developer recovery unit, 46 ... transfer belt cleaning roller, 47 ... transfer belt cleaning roller cleaning blade, 49 ... transfer belt cleaning blade, 50Y, 50M, 50C, 50K ... Primary transfer section, 51Y, 51M, 51C, 51K ... primary transfer backup roller, 5 53 ... tension roller, 60 ... secondary transfer unit, 61 ... secondary transfer roller, 62 ... secondary transfer roller cleaning blade, 74 ... (cleaning) blade holding member, ..Secondary transfer unit collection and storage unit, 90... Fixing unit, 91... Heating roller, 92... Pressure roller, 101, 101 '. 131 ... 1st detection part, 132 ... 2nd detection part, 133 ... Belt position detection part, 134 ... Motor controller, 135 ... Drive motor, 139 ... Claw piece for detection, 150: main control unit, 210: first suction device, 211: housing unit, 212: suction surface, 215: air flow generation unit, 230: transfer material transport device, 231・..Case unit, 232... Suction surface, 233 .. partition member, 235 .. air flow generation unit, 250... Transfer material transport member, 251. 253: Transfer material conveying member stretching roller, 270: Second suction device, 271: Housing portion, 272 ... Suction surface, 275 ... Airflow generating portion, 400 ... Blower , 401, casing, 402, opening, 405, air flow generating unit, 601, roller body, 602, roller shaft, 605, opening recess, 607,. Elastic member 610: Transfer material gripping mechanism 611 Transfer material gripping portion 612 Transfer material gripping portion receiving portion 640 Transfer material peeling member

Claims (8)

A transfer roller having a transfer material gripping part for gripping the transfer material;
An airflow forming section for generating an airflow;
A ventilation hole non-formation region in the transfer material conveyance direction, and a ventilation hole formation region in the transfer material conveyance direction in which a ventilation hole through which the airflow formed in the airflow formation unit passes is provided. A transfer material conveying belt that conveys the transfer material transferred by the transfer roller while being sucked by the airflow in the air hole forming region;
An image forming apparatus comprising: a control unit that controls a rotational position of the transfer material conveyance belt. The image forming apparatus according to claim 1, wherein the control unit controls a speed at which the transfer material conveyance belt rotates. A fixing unit for fixing the transfer material conveyed by the transfer material conveyance belt;
The peripheral speed of the transfer roller is v _2T ,
The rotation speed of the transfer material conveying belt is v,
When the transfer material conveyance speed of the fixing unit is v _F ,
v _F >v> v _2T
The image forming apparatus according to claim 1, wherein the image forming apparatus has the following relationship. An image carrier that carries an image and forms a transfer nip by contacting the transfer roller with the transfer material;
The fixing unit includes a first roller and a second roller that contacts the first roller and the transfer material to form a fixing nip,
4. The image forming apparatus according to claim 1, wherein the transfer material is not simultaneously nipped between the transfer nip and the fixing nip. 5. The image forming apparatus according to claim 1, wherein the control unit controls a speed of a driving roller that drives the transfer material conveyance belt. The image forming apparatus according to claim 1, wherein the control unit controls an operation of a driving roller that drives the transfer material conveyance belt. The length in the transport direction of the transfer material in the air hole non-formation region is longer than the length in the transport direction of the transfer material in the region in which the transfer material is sucked and transported by the airflow in the air hole formation region. The image forming apparatus according to claim 1. Grasping the transfer material with the transfer material gripping part provided on the transfer roller,
Transfer material conveyance having a ventilation hole non-formation area in the conveyance direction of the transfer material and a ventilation hole formation area in the conveyance direction of the transfer material provided with a ventilation hole through which the airflow formed by the airflow formation portion passes. An image forming method using a belt and sucking and transporting the transfer material released from the transfer material gripping portion in the vent hole forming region by controlling the rotational position of the transfer material transport belt .

Images