JP6226607B2 - Image forming apparatus provided with transfer means, or fixing method of transfer means - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile machine, and a multi-function machine that forms an image by electrophotography.

  2. Description of the Related Art Conventionally, for example, in an image forming apparatus using an electrophotographic system, a toner image, which is a developer image, is formed on an electrophotographic photoreceptor as an image carrier. Then, a transfer process is performed in which the toner image is electrostatically transferred from the photosensitive member to the transfer material carried on the transport belt or to the intermediate transfer belt. In the transfer process, a voltage having a polarity opposite to the normal polarity of the toner is applied to the transfer unit from the transfer power source, and the transfer unit to which the voltage is applied is in contact with the inner peripheral surface of the intermediate transfer belt or the conveyance belt. As this transfer means, a configuration including a contact member that contacts a transfer belt such as a roller shape, a blade shape, or a brush shape has been conventionally known.

  Patent Document 1 discloses a transfer unit including a brush-like contact member. Patent Document 1 discloses a configuration in which a brush-like contact member made of a plurality of conductive fibers is brought into contact with a transfer belt with a predetermined inclination angle. Patent Document 1 proposes that an antistatic member that shields and leaves the tip of the contact member is provided so that only the exposed upstream end of the contact member serves as a contact portion for the photosensitive member.

Japanese Patent Laid-Open No. 10-232574

  In general, if there is an upstream end (contact start end) of the contact area between the transfer belt and the contact member outside the contact area between the transfer belt and the photosensitive member in the moving direction of the transfer belt, it is applied to the transfer means. An electric field is formed between the photosensitive member and the contact member by the applied voltage. Due to the influence of the electric field, the toner image on the photoconductor may be transferred to the transfer belt before the contact area between the transfer belt and the photoconductor, which may cause image quality degradation such as scattering. Therefore, it is necessary to accurately position the contact member with respect to the contact area between the transfer belt and the photoconductor.

  However, in the transfer means including the brush-like contact member of Patent Document 1, it is difficult to accurately manage the position where the contact member contacts the transfer belt due to variations in conductive fibers forming the brush. Therefore, it is difficult to position the transfer unit with respect to the photoconductor, and depending on the positioned position, the upstream end of the contact region between the contact member and the transfer belt greatly protrudes from the contact region between the transfer belt and the photoconductor, thereby causing scattering. There is a risk.

  Therefore, an object of the present invention is to position the transfer means with high accuracy with a simple configuration and to suppress the occurrence of scattering.

In order to solve the above problems, the present invention provides an image carrier that carries a toner image, a transfer belt that can move in contact with the image carrier, and a position that faces the image carrier via the transfer belt. A transfer unit disposed and configured to transfer a toner image carried from the image carrier to the transfer belt side, and a fixing member provided so that a relative position with respect to the image carrier is determined. An image forming apparatus comprising: a raised portion made of a plurality of conductive fibers in contact with the transfer belt; and a base portion that contacts the raised portion and supports the raised portion. A holding member that holds a surface opposite to the surface that contacts the raised portion of the portion, the holding member is fixed to the fixing member, and the holding member is related to the moving direction of the transfer belt, At least said group Characterized in that it includes a hole or cutout in a position corresponding to one end of the section.

  In order to solve the above problems, another aspect of the present invention provides an image carrier that carries a toner image, a transfer belt that can move in contact with the image carrier, and the image carrier via the transfer belt. A transfer unit that is disposed at an opposing position and transfers a toner image carried from the image carrier to the transfer belt side, and a fixing member provided so that a relative position with respect to the image carrier is determined; In the image forming apparatus, the transfer unit includes a raised portion made of a plurality of conductive fibers in contact with the transfer belt, and a base material portion that contacts the raised portion and supports the raised portion. And a holding member that holds a surface opposite to the surface that contacts the raised portion of the base material portion, the holding member being fixed to the fixing member, and the holding member being transparent It is characterized by.

In order to solve the above problems, another aspect of the present invention provides an image carrier that carries a toner image, a transfer belt that can move in contact with the image carrier, and the image carrier via the transfer belt. A transfer unit that is disposed at an opposing position and transfers a toner image carried from the image carrier to the transfer belt side, and a fixing member provided so that a relative position with respect to the image carrier is determined; The transfer means is in contact with the raised portion made of a plurality of conductive fibers in contact with the transfer belt, the base portion that contacts the raised portion and supports the raised portion, and the raised portion of the base portion. In the method of fixing the transfer unit to the fixing member in an image forming apparatus including a holding member that holds a surface opposite to the surface, one end of the base material portion that is fixed in advance to the holding member is connected to the holding member. Detected through By based on the detection result fixing one end of said base portion in a predetermined position of the fixing member, characterized by securing said transfer means to said fixing member.

  According to the present invention, the positioning of the transfer means can be performed with a simple configuration with high accuracy by positioning one end of the base material portion supporting the contact member as a reference, and the occurrence of scattering is suppressed. Is possible.

1 is a schematic diagram of an image forming apparatus according to a first embodiment. Sectional view of the image forming apparatus of Embodiment 1 Sectional view of the photosensitive drum unit and intermediate transfer belt unit Explanatory drawing of photoconductor drum unit and intermediate transfer belt unit Schematic explaining the transfer means of Embodiment 1 The perspective view of the transcription | transfer means and fixing jig in Embodiment 1. Sectional drawing of transfer means and fixing jig in Embodiment 1 The perspective view of the transfer means after fixing the transfer means with the fixing jig in Embodiment 1. Sectional drawing of the transfer means after fixing the transfer means by the fixing jig in Embodiment 1. Schematic explaining the transfer means of Embodiment 2 The perspective view of the transcription | transfer means and fixing jig in Embodiment 2. Sectional drawing of the transfer means and fixing jig in Embodiment 2 The perspective view of the transfer means after fixing the transfer means with the fixing jig in Embodiment 2. Sectional drawing of the transfer means after fixing a transfer means with the fixing jig in Embodiment 2

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions. Therefore, unless specifically stated otherwise, the scope of the present invention is not intended to be limited thereto.

(Embodiment 1)
FIG. 1 is a schematic diagram illustrating an example of a color image forming apparatus. The image forming apparatus 100 forms an image on a transfer material such as a recording sheet or an OHP sheet by an electrophotographic method in accordance with a signal sent from an external device such as a personal computer that is communicably connected to the image forming apparatus 100. be able to. FIG. 2 is a cross-sectional view of the image forming apparatus according to the present embodiment.

  The image forming apparatus according to the present embodiment will be described by taking a rotary (developer rotating) type four-cycle full-color image forming apparatus as an example.

[Outline of image forming operation of color image forming apparatus]
The photosensitive drum 1 (image carrier) is moved in synchronization with the rotation of the intermediate transfer belt 5 stretched around the driving roller 40, the first driven roller (tension roller) 41, and the second driven roller (idler roller) 42. Rotate in the arrow direction (clockwise) in FIG. The surface of the rotating photosensitive drum 1 is uniformly charged by the charging means 2. Thereafter, the yellow image is exposed by the exposure means 3 to form a yellow electrostatic latent image on the photosensitive drum 1. Simultaneously with the formation of the electrostatic latent image, the rotary developing unit 4 is driven to place the yellow developing device 4Y at the developing position. Then, the yellow toner is attached to the electrostatic latent image by applying a voltage having the same polarity as the charging polarity on the photosensitive drum 1 so that the yellow toner is attached to the electrostatic latent image on the photosensitive drum 1. And develop. Thereafter, the yellow toner image on the photosensitive drum 1 is primarily transferred toward the intermediate transfer belt 5 side (transfer belt side) by the transfer means 7 in the intermediate transfer belt unit.

  When the primary transfer of the yellow toner image is completed as described above, the next developing device rotates. Then, it is positioned at the development position facing the photosensitive drum 1, and in the same manner as in the case of yellow, formation of electrostatic latent images, development, and primary transfer are sequentially performed for each color of magenta, cyan, and black, and an intermediate transfer belt. A toner image of 4 colors is superimposed on 5.

  During this time, the secondary transfer roller 11 is not in contact with the intermediate transfer belt 5. At this time, the charging brush 22 and the charging roller 23 as a cleaning unit are also in a non-contact state with the intermediate transfer belt 5.

  After the formation of the four color toner images on the intermediate transfer belt 5, the secondary transfer roller 11 is brought into contact with the intermediate transfer belt 5 (state shown in FIG. 2), and further in synchronization with the rotation of the intermediate transfer belt 5. The transfer material is separated and fed one by one from the stacking means 19 by the pickup roller 18. Then, the transfer material is waited by the registration roller pair 17 and sent to the secondary transfer nip portion of the intermediate transfer belt 5 and the secondary transfer roller 11 in accordance with the toner image of the intermediate transfer belt 5.

  Here, a registration sensor (not shown) is provided immediately before the conveying roller pair 17 to detect the leading edge of the transfer material, temporarily cut off the rotational driving force of the conveying roller pair 17 and wait the transfer material at a predetermined position. . Further, a voltage having a polarity opposite to that of the toner is applied to the secondary transfer roller 11, and the toner image on the intermediate transfer belt 5 is secondarily transferred onto the surface of the transfer material that has been conveyed all at once.

  The transfer material secondary-transferred in this way reaches the fixing device 8, and after fixing the toner images of a plurality of colors, it is placed on the discharge tray 10 above the color image forming apparatus A by the discharge roller pair 9. The paper is discharged and image formation is completed.

  On the other hand, after the secondary transfer, the cleaning charging brush 22 and the charging roller 23 are brought into contact with the intermediate transfer belt 5, and the residual toner remaining on the intermediate transfer belt 5 is charged to a polarity opposite to the normal polarity (positive polarity). The charged residual toner is electrostatically moved from the intermediate transfer belt 5 to the photosensitive drum 1 at the primary transfer nip portion (contact portion between the intermediate transfer belt 5 and the photosensitive drum 1). It is collected by the cleaning blade 6 for use.

  Here, the driving roller 40 is wider than the secondary transfer roller 11 in the width direction, and wider than the charging brush 22 and the charging roller 23. The driving roller 40 is coated with a rubber having a low electrical resistance and has a function as a counter electrode of the secondary transfer roller 11, the charging brush 22, and the charging roller 23.

[Intermediate transfer belt unit and photosensitive drum unit]
3 is a schematic sectional view of the intermediate transfer belt unit 21 and the photosensitive drum unit 20, and FIG. 4 is an explanatory view of the intermediate transfer belt unit 21 and the photosensitive drum unit 20 of FIG. 3 as viewed from above.

  Here, the intermediate transfer belt unit 21 includes at least an intermediate transfer belt 5 (transfer belt), a driving roller 40, first and second driven rollers 41 and 42, transfer means 7, a charging brush 22, and a charging roller 23. Are integrated into a unit. The photosensitive drum unit 10 includes at least the photosensitive drum 1, the charging roller 2, and the waste toner box 16, and is a unitized unit.

  The photosensitive drum unit 20 is held on the photosensitive drum unit 20 by a right bearing 202 and a left bearing 206 so as to be rotatable at both ends, and a predetermined rotational driving force is transmitted from the apparatus main body via a coupling 49 at the right end. It has become.

  Further, the charging roller 2 is pressed against the photosensitive drum 1 with a predetermined force by a compression spring 26 via bearings 25 at both ends, and is driven to rotate.

  The intermediate transfer belt unit 21 is stretched by a driving roller 40, a first driven roller (tension roller) 41, and a second driven roller (idler roller) 42.

  The drive roller 40 is rotatably supported at both ends by a right bearing 201 and a left bearing 205, and a predetermined rotational drive is transmitted from the apparatus main body via a drive gear 48 of the right bearing portion. The bearings at both ends of the first driven roller 41 are provided with compression springs 44 so as to apply a predetermined tension to the intermediate transfer belt 5.

  A transfer means 7 is provided at a position facing the photosensitive drum 1 with the intermediate transfer belt 5 interposed therebetween, and is brought into pressure contact with a predetermined force by a compression spring 47 via a transfer support member 46.

  By applying a predetermined bias to the transfer means 7 from a power supply circuit (not shown), the toner image on the surface of the photosensitive drum 1 is primarily transferred onto the intermediate transfer belt 5.

  Further, the intermediate transfer unit 21 of the present embodiment includes a light reflector marker 71 attached to the outside of the intermediate transfer belt 5 in the width direction image forming area. Further, the intermediate transfer unit 21 of the present embodiment includes a detection unit 70 that detects a toner patch formed on the intermediate transfer belt 5, and a counter member 72 that faces the detection unit 70 through the intermediate transfer belt 5. Yes. Based on the detection result of the detection means 70, the image forming apparatus 100 can correct the density and color misregistration.

[Transfer means 7]
Next, the transfer unit 7 in the image forming apparatus 100 of this embodiment will be described in detail. FIG. 5 is a schematic diagram illustrating the transfer unit 7.

  The transfer means 7 includes a raised portion 7a made of a plurality of conductive fibers that contact the intermediate transfer belt 5, a base portion 7b that supports the raised portion 7a, and a holding member 7d that holds the base portion 7b. The material portion 7b and the holding member 7d are bonded by a double-sided tape 7c (bonding portion). Here, the raised portion 7 a is a contact member in which a plurality of conductive fibers are in a brush shape and come into contact with the intermediate transfer belt 5. 7 d of holding members hold | maintain the surface on the opposite side to the surface where the base material part 7b supports the raising part 7a. If the base material portion 7b is a pile woven type brush, it is a base fabric for weaving raised fibers made of fibers, and if it is an electrostatic flocking type brush, the film member to which the raised hair is bonded and its adhesive layer It is.

  In the present embodiment, a transparent PET film that is a transparent member is used as the holding member 7d, and the reason will be described later.

  The elastic body 14 in contact with the holding member 7d is a substantially rectangular rubber, and is pressed toward the intermediate transfer belt 5 via the transfer means 7 by the compression spring 47. That is, the elastic body 14 presses the transfer unit 7 against the intermediate transfer belt 5 at a position facing the photosensitive drum 1. One surface of the elastic body 14 is in contact with the back surface of the holding member 7d. The coefficient of friction between the surface of the raised portions 7a and the intermediate transfer belt 5 is set low, and the intermediate transfer belt 5 can move stably.

  The transfer support member 46 supports the elastic body 14, and the elastic body 14 is fixed by being bonded to the transfer support member 46. On the other hand, the holding member 7 d of the transfer means 7 is fixed by being bonded to the fixing member 12 by the double-sided tape 13. The fixing member 12 and the transfer support member 46 are fixed by screws (not shown). The fixing member 12 is made of sheet metal, is positioned with respect to the moving direction of the intermediate transfer belt 5 on the frame 16 of the intermediate transfer belt unit, and is supported so as to be movable in the vertical direction. The frame 16 of the intermediate transfer belt unit is positioned with respect to the photosensitive drum 1 in the moving direction and the vertical direction of the intermediate transfer belt 5 (not shown). The fixing member 12 is a fixing member provided so that the relative position with respect to the photosensitive drum 1 is determined. For this reason, the transfer means 7 bonded and fixed to the fixing member 12 is positioned at a predetermined position with respect to the moving direction of the intermediate transfer belt 5 with respect to the photosensitive drum 1.

  Next, the positional relationship of the transfer unit 7 with respect to the moving direction of the intermediate transfer belt 5 will be described. Since the photosensitive drum 1 and the intermediate transfer belt 5 are installed in contact with each other, a physical contact region (physical nip) exists between the photosensitive drum 1 and the intermediate transfer belt 5. The width of the physical nip is indicated by the distance A. The transfer means 7 is in contact with the back surface of the intermediate transfer belt 5 through the raised portion 7a, and the contact start end of the raised portion 7a with the intermediate transfer belt 5 is indicated as B, and the contact end end is indicated as C. Here, it is preferable that the contact start end B is within the range of the physical nip A, the contact end end C is outside the range of the physical nip, and the intermediate transfer belt 5 is moved downstream in the operation.

  The width of the raised portion 7a of the transfer means 7 is at least wider than the image printing area width that can be printed by the image forming apparatus 100 described in the present embodiment with respect to the direction orthogonal to the moving direction of the intermediate transfer belt 5, and Is positioned outside the image print area width. In addition, the width of the raised portion 7 a of the transfer unit 7 is shorter than the intermediate transfer belt 5 in the direction orthogonal to the moving direction of the intermediate transfer belt 5, and both ends are located inside the both ends of the intermediate transfer belt 5. . The transfer unit 7 and the primary transfer voltage power source are connected to the primary transfer power source via a contact plate (not shown) or the like by extending at least a part of the transfer unit 7 in the moving direction of the intermediate transfer belt 5.

[Positioning and fixing method of transfer means 7]
Next, a method for fixing the transfer means 7 of the present embodiment to the fixing member 12 will be described in detail with reference to FIGS.

  FIG. 6 is a perspective view of the fixing device 300 for fixing the transfer means 7 to a predetermined position with respect to the fixing member 12 and the transfer means 7 before being fixed to the fixing member 12. FIG. 7 is a sectional view of the transfer means 7 before fixing the fixing means 300 to the fixing member 12 and the fixing jig 300 for fixing the transfer means 7 to the fixing member 12 in a predetermined position.

  The fixing jig 300 includes a positioning part 300a, an alignment scale 300b, a movable stage 300c, a micrometer 300d, and a pin 300e.

  When fixing with the fixing jig 300, the transfer means 7 is oriented so that the raised portion 7a faces downward, and the pin 300e of the movable stage 300c and the opening 7e of the holding member 7d are engaged and positioned. . (The opening 7e of the holding member 7d is a positioning hole formed in the holding member 7d, which will be described with reference to FIG. 8.) In this state, the holding member 7 is a suction hole (not shown) of the movable stage 300c. The air is adsorbed and fixed to the fixing jig 300.

  The movable stage 300c can be translated in the short direction of the transfer means (direction of arrow E) by the micrometer 300d. Since the holding member 7d of the transfer means 7 is a transparent PET film as described above, the position of the base material portion 7b can be visually confirmed through the holding member 12 from above the fixing jig 300 (in the direction of arrow D).

  The fixing member 12 is fixed to the fixing jig 300 by positioning the positioning portion 12a of the fixing member to the positioning portion 300a of the fixing jig and adsorbing the holding member 7d by air adsorption through an adsorption hole (not shown).

  As shown in FIG. 7, when the width of the double-sided tape 7 c is narrower than that of the base material portion 7 b and is inside, the movable stage 300 c is moved in parallel, and the short-side direction of the base material portion 7 b of the transfer unit 7 is moved. The position of one end is visually aligned with the alignment scale 300b. By visual alignment, the relative position of the transfer means 7 and the fixing member 12 in the short direction can be adjusted to a predetermined position.

  On the other hand, when the width of the double-sided tape 7c is wider than that of the base 7b and is on the outside, the position of one end of the double-sided tape in the short direction is visually aligned with the alignment scale 300b. By visual alignment, the relative position of the transfer means 7 and the fixing member 12 in the short direction is adjusted to a predetermined position.

After the alignment, the fixing member 12 is moved up and down by an elevating mechanism (not shown) of the fixing jig 300 and is bonded and fixed to the holding member 7d by the double-sided tape 13. At this time, in order to avoid interference with the pin 300e of the movable stage 300c, the fixed member 12 and the double-sided tape 13 are provided with an opening sufficiently larger than the size of the pin 300e. Therefore, the fixed member 12 and the double-sided tape 13 do not interfere with the movable stage 300c. (The dotted lines of the fixing member 12 and the double-sided tape 13 in FIG. 7 indicate the openings.)
Up to this point, the case where the movable stage 300c of the fixed jig 300 is translated in the short direction by the micrometer 300d has been described. Further, in order to correct the inclination in the longitudinal direction of the transfer means 7 at the time of alignment, it may be rotatable. Alternatively, the movable stage 300c is divided into a plurality of parts in the longitudinal direction, and can be aligned with each other by correcting the inclination in the longitudinal direction of the transfer means 7 by parallel movement (in the direction of arrow E) by a plurality of micrometers. It may be. Further, a plurality of alignment marks 300b of the fixing jig 300 may be provided.

  Further, the case has been described so far in which the movable stage 300c of the fixed jig 300 is moved by the micrometer 300d and the position of the end portion in the longitudinal direction of the base material portion 7b of the transfer means 7 is visually aligned with the alignment scale 300b. An optical sensor may be used. The optical sensor detects the position of the end portion in the longitudinal direction of the base material portion 7b through the transparent holding member 7d, thereby matching the relative position in the short direction of the transfer means 7 and the fixing member 12 to a predetermined position. Is possible.

  FIG. 8 is a perspective view after the transfer means 7 is fixed by the fixing jig 300. FIG. 9 is a sectional view after the transfer means 7 is fixed by the fixing jig 300. By using the fixing jig 300, the relative position of the transfer means 7 and the fixing member 12 in the short direction is adjusted to a predetermined position and bonded by the double-sided tape 13. X is the relative distance between the predetermined transfer means 7 and the reference position in the short direction of the fixing member 12 required for the transfer means 7 to be positioned at a predetermined position with respect to the photosensitive drum 1. Y is the amount of deviation between the raised portions 7a and the end portions of the substrate portion 7d when the width of the raised portions 7a of the transfer means 7 is wider than the width of the substrate portion 7b due to the inclination of the hair.

  For example, when the positioning of the transfer means 7 and the fixing member 12 is performed from the raised portion 7a side, the accuracy is deteriorated by the error Y. In this embodiment, by using a transparent PET film for the holding member 7d, as described above, the relative position with respect to the transfer means 7 and the fixing member 12 is changed from the base material portion 7b side through the holding member 7d to the base material portion 7b. The position can be adjusted so that the position can be confirmed.

  With this configuration, the raised portion 7a is non-contacting without damage and can be positioned with high accuracy to the desired relative distance X without including the error Y.

  The holding member 7d may be a member other than a transparent PET film. For example, a transparent polycarbonate film may be used. Since the holding member 7d does not need conductivity, the holding member 7d may not include a conductive material such as carbon. When the position of the base material portion 7b is detected by the optical sensor via the holding member 7d, a member having a transmittance that allows the optical sensor to discriminate between the holding member 7d and the base material portion 7b even if not transparent is used. May be.

  As described above, according to the above configuration, it is possible to position the transfer means with high accuracy with a simple configuration, and it is possible to obtain better and stable transferability.

(Embodiment 2)
In the first embodiment, a case has been described in which a transparent PET film is used as the holding member 7d in order to detect the end of the base material portion 7b via the holding member 7d. In contrast, the present embodiment is characterized in that an opening is provided in the holding member 7d and the end of the base material portion 7b is detected through the opening. Since other configurations are the same as those of the image forming apparatus according to the first embodiment, the same portions are denoted by the same reference numerals and described.

  The transfer unit 7 in the image forming apparatus 100 of this embodiment will be described in detail. The structure of the transfer means 7 is shown in FIG.

  In the present embodiment, a holding member 7g having a hole 7f is used instead of the holding member 7d of the first embodiment. The hole 7f of the holding member 7d is provided at a position corresponding to one end of the base member 7b in the short direction. The holding member 7g may not be transparent, and a plurality of holes 7f provided in the holding member 7g may be provided at the end portion of the base material portion 7b. In addition, instead of providing an opening in the holding member 7g, the shape of the holding member 7g itself may have a notch shape at the end of the base material portion 7b. The holding member 7g is bonded and fixed to the fixing member 12 by the double-sided tape 13 as described above.

  Next, the positional relationship of the transfer unit 7 with respect to the moving direction of the intermediate transfer belt 5 will be described. Since the photosensitive drum 1 and the intermediate transfer belt 5 are installed in contact with each other, a physical contact region (physical nip) exists between the photosensitive drum 1 and the intermediate transfer belt 5. The width of the physical nip is indicated by the distance A. The transfer means 7 is in contact with the back surface of the intermediate transfer belt 5 through the raised portion 7a, and the contact start end of the raised portion 7a with the intermediate transfer belt 5 is indicated as B, and the contact end end is indicated as C. Here, it is preferable that the contact start end B is within the range of the physical nip A, the contact end end C is outside the range of the physical nip, and the intermediate transfer belt 5 is moved downstream in the operation.

  The width of the raised portion 7a of the transfer means 7 is at least wider than the image printing area width that can be printed by the image forming apparatus 100 described in the present embodiment with respect to the direction orthogonal to the moving direction of the intermediate transfer belt 5, and Is positioned outside the image print area width. In addition, the width of the raised portion 7 a of the transfer unit 7 is shorter than the intermediate transfer belt 5 in the direction orthogonal to the moving direction of the intermediate transfer belt 5, and both ends are located inside the both ends of the intermediate transfer belt 5. The transfer unit 7 and the primary transfer voltage power source are connected to the primary transfer power source via a contact plate (not shown) or the like by extending at least a part of the transfer unit 7 in the moving direction of the intermediate transfer belt 5.

  Next, a method for fixing the transfer means 7 of this embodiment to the fixing member 12 will be described in detail with reference to FIGS. The fixing jig 300 used in the present embodiment is the same as the fixing jig of the first embodiment, and a detailed description regarding each member is omitted.

  FIG. 11 is a perspective view of the fixing device 300 for fixing the transfer means 7 at a predetermined position with respect to the fixing member 12 and the transfer means 7 before being fixed to the fixing member 12. FIG. 12 is a cross-sectional view of the transfer means 7 before fixing the fixing means 300 to the fixing member 12 and the fixing jig 300 for fixing the transfer means 7 to the fixing member 12. The transfer means 7 is oriented so that the raised portion 7a is on the lower side, and is positioned by the pin 300e of the movable stage 300c of the fixed jig 300 and the opening 7e of the holding member 7g. The holding member 7g is fixed to the fixing jig 300 by adsorbing the holding member 7g by air adsorption through an adsorption hole (not shown) of the movable stage 300c. The movable stage 300c can be translated in the short direction (direction of arrow E) of the transfer means 7 by a micrometer 300d. As described above, the holding member 7g of the transfer means 7 is provided with the hole 7f at the end portion of the base portion 7b, so that the holding member 7g is fixed from the upper side of the fixing jig 300 (in the direction of arrow D). 12, the position of the base material portion 7b can be confirmed. The fixing member 12 is fixed to the fixing jig 300 by positioning the positioning portion 12a of the fixing member to the positioning portion 300a of the fixing jig and adsorbing the holding member 7g by air adsorption through an adsorption hole (not shown).

  As shown in FIG. 12, when the width of the double-sided tape 7c is narrower than the base 7b and is inside, the movable stage 300c is moved in parallel and the base 7b of the transfer means 7 is short. The position of one end is visually aligned with the alignment scale 300b. By visual alignment, the relative position of the transfer means 7 and the fixing member 12 in the short direction can be adjusted to a predetermined position. On the other hand, when the width of the double-sided tape 7c is wider than that of the base 7b and is on the outside, the position of one end of the double-sided tape in the short direction is visually aligned with the alignment scale 300b. By visual alignment, the relative position in the short direction of the transfer means 7 and the fixing member 12 is adjusted to a predetermined position.

  After the alignment, the fixing member 12 is moved up and down by an elevating mechanism (not shown) of the fixing jig 300 and bonded and fixed to the holding member 7g by the double-sided tape 13. At this time, in order to avoid interference with the pin 300e of the movable stage 300c, the fixed member 12 and the double-sided tape 13 are provided with an opening sufficiently larger than the size of the pin 300e. Therefore, the fixed member 12 and the double-sided tape 13 do not interfere with the movable stage 300c.

  Up to this point, the case where the movable stage 300c of the fixed jig 300 is translated in the short direction by the micrometer 300d has been described. Further, it may be rotatable so as to correct the inclination in the longitudinal direction of the transfer means 7 at the time of alignment. Alternatively, the movable stage 300c is divided into a plurality of parts in the longitudinal direction, and can be aligned with each other by correcting the inclination in the longitudinal direction of the transfer means 7 by parallel movement (in the direction of arrow E) by a plurality of micrometers. It may be. Further, a plurality of alignment marks 300b of the fixing jig 300 may be provided.

  Further, the relative position in the short direction of the transfer means 7 and the fixing member 12 may be adjusted to a predetermined position by detecting the position of the end portion of the base material portion 7b in the longitudinal direction using an optical sensor.

  FIG. 13 is a perspective view after the transfer means 7 is fixed by the fixing jig 300. FIG. 14 is a sectional view after the transfer means 7 is fixed by the fixing jig 300. By using the fixing jig 300, the relative position of the transfer means 7 and the fixing member 12 in the short direction is adjusted to a predetermined position and bonded by the double-sided tape 13. X is the relative distance between the predetermined transfer means 7 and the reference position in the short direction of the fixing member 12 required for the transfer means 7 to be positioned at a predetermined position with respect to the photosensitive drum 1. Y is the amount of deviation between the raised portion 7a and the end of the substrate 7d when the width of the raised portion 7a of the transfer means 7 is wider than the width of the substrate 7b due to the inclination of the hair. For example, when the positioning of the transfer means 7 and the fixing member 12 is performed from the raised portion 7a side, the accuracy is deteriorated by the error Y.

  In the present embodiment, the holding member 7g of the transfer means 7 is provided with an opening at the position of the end of the base material portion 7b, so that the relative position of the transfer means 7 and the fixing member 12 can be set as described above. The position of the base material portion 7b can be confirmed through the holding member 12 from the side. With this configuration, the transfer unit 7 can be positioned with high accuracy at a desired relative distance X without causing any damage to the raised portions 7a and without including the error Y.

  As described above, according to the above configuration, even when the holding member 7d is not transparent, the transfer unit can be positioned with high accuracy with a simple configuration as in the first embodiment.

  In the first and second embodiments, the image forming apparatus including the intermediate transfer belt 5 as the transfer belt has been described. However, the configurations of the first and second embodiments can also be applied to an image forming apparatus including a conveyance belt that carries and conveys a transfer material as a transfer belt.

DESCRIPTION OF SYMBOLS 100 Image forming apparatus 1 Photoconductor drum 21 Intermediate transfer belt unit 5 Intermediate transfer belt 7 Transfer means 7a Raised portion 7b Base material portion 7c Double-sided tape 7d Holding member 12 Fixing member

Claims (15)

An image carrier for carrying a toner image;
A transfer belt movable in contact with the image carrier;
A transfer unit disposed at a position facing the image carrier via the transfer belt, and transferring a toner image carried from the image carrier to the transfer belt;
A fixing member provided so as to determine a relative position with respect to the image carrier,
In the image forming apparatus, the transfer unit includes a raised portion made of a plurality of conductive fibers that are in contact with the transfer belt, and a base material portion that is in contact with the raised portion and supports the raised portion.
The transfer means includes a holding member that holds a surface opposite to the surface that contacts the raised portion of the base material portion, and the holding member is fixed to the fixing member. An image forming apparatus comprising a hole portion or a notch portion at least at a position corresponding to one end of the substrate portion with respect to a moving direction of the transfer belt .   The image forming apparatus according to claim 1, wherein the holding member is transparent. The image forming apparatus according to claim 1 , wherein the holding member includes a plurality of the hole portions or the chipped portions at a position corresponding to the one end of the base material portion.   The image forming apparatus according to claim 1, wherein the holding member and the fixing member are bonded to each other by a double-sided tape. Before SL fixing member, wherein the double-sided tape is respectively openings formed, the image forming apparatus according to claim 4, characterized in that overlap respective openings.   The base part includes an adhesive part, and the base part is adhered to the holding member by the adhesive part, and the width of the adhesive part is shorter than the width of the base part with respect to the moving direction of the transfer belt. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.   The image forming apparatus according to claim 1, wherein the fixing member is a sheet metal. An image carrier for carrying a toner image;
A transfer belt movable in contact with the image carrier;
A transfer unit disposed at a position facing the image carrier via the transfer belt, and transferring a toner image carried from the image carrier to the transfer belt;
A fixing member provided so as to determine a relative position with respect to the image carrier,
In the image forming apparatus, the transfer unit includes a raised portion made of a plurality of conductive fibers that are in contact with the transfer belt, and a base material portion that is in contact with the raised portion and supports the raised portion.
The transfer means includes a holding member that holds a surface opposite to the surface that contacts the raised portion of the base material portion, and the holding member is fixed to the fixing member. An image forming apparatus characterized by being transparent.   The image forming apparatus according to claim 8, wherein the holding member and the fixing member are bonded to each other by a double-sided tape.   The image forming apparatus according to claim 9, wherein the holding member, the fixing member, and the double-sided tape each have an opening, and the openings overlap each other.   The base part includes an adhesive part, and the base part is adhered to the holding member by the adhesive part, and the width of the adhesive part is longer than the width of the base part with respect to the moving direction of the transfer belt. The image forming apparatus according to claim 8, wherein the image forming apparatus is an image forming apparatus.   The image forming apparatus according to claim 11, wherein the holding member is fixed to the fixing member with reference to one end of the adhesive portion in the moving direction of the transfer belt.   The image forming apparatus according to claim 1, wherein the transfer belt is an intermediate transfer belt to which a toner image is transferred from the image carrier.   The image forming apparatus according to claim 1, wherein the transfer belt is a conveyance belt that carries and conveys a transfer material onto which a toner image is transferred from the image carrier. An image carrier that carries a toner image, a transfer belt that can move in contact with the image carrier, and a position that faces the image carrier via the transfer belt, and is carried from the image carrier. A transfer unit configured to transfer a toner image to the transfer belt; and a fixing member provided so that a relative position with respect to the image carrier is determined. The transfer unit includes a plurality of conductive members that contact the transfer belt. An image comprising a raised portion made of a conductive fiber, a base material portion that contacts the raised portion and supports the raised portion, and a holding member that holds a surface of the base portion opposite to the surface that contacts the raised portion. In the method of fixing the transfer means in the forming apparatus to the fixing member,
By detecting one end of the base material portion fixed in advance to the holding member through the holding member, and fixing one end of the base material portion to a predetermined position of the fixing member based on the detection result, A fixing method comprising fixing the transfer means to the fixing member.

Images