JP2021086092A - Image forming apparatus - Google Patents

Abstract

To solve the problem in which poor cleaning may occur when a toner accumulated near a recovery member is pressed together in a configuration to recover a toner remaining on an image carrier with the recovery member in contact with the image carrier.SOLUTION: An intermediate transfer belt 10 has a plurality of grooves 45 formed along a direction of movement of the intermediate transfer belt 10, on a surface on an outer peripheral surface in contact with a blade 51, with respect to a width direction of the intermediate transfer belt 10 intersecting with the direction of movement of the intermediate transfer belt 10. When viewed from a direction of an axis of rotation of a stirring member 52, an area of the blade 51 with which a toner is in contact, the area being at least a partial area on a free end of the blade 51 with respect to the direction of movement of the intermediate transfer belt 10, overlaps an area of a rotation locus Rm of an outermost peripheral part of the stirring member 52.SELECTED DRAWING: Figure 7

Description

The present invention relates to an image forming apparatus such as a copier or a printer using an electrophotographic method.

Conventionally, as an electrophotographic image forming apparatus, a configuration including a transfer belt or a photosensitive drum as an image carrier for supporting a toner image and a cleaning means for collecting the toner remaining on the transfer belt or the photosensitive drum is known. Has been done. The cleaning means includes a frame and a cleaning blade provided in contact with the transfer belt and the photosensitive drum as a recovery member for recovering the toner remaining on the transfer belt and the photosensitive drum.

Patent Document 1 describes a configuration of an image forming apparatus including a cleaning means including a transport member for transporting toner recovered from a photosensitive drum by a cleaning blade, and an accommodating portion for accommodating toner recovered by the cleaning means. It is disclosed. In Patent Document 1, the toner collected by the cleaning blade is provided in the frame and is conveyed to the accommodating portion by a conveying member such as a screw that rotates by receiving a driving force.

Japanese Unexamined Patent Publication No. 2016-218435

In Patent Document 1, the toner recovered by the cleaning blade is deposited in the vicinity of the cleaning blade, reaches the transport member, and is then transported by the transport member. As the toner continues to be collected by the cleaning blade and the amount of toner accumulated in the vicinity of the cleaning blade increases, the pressure applied to the toner staying in the vicinity of the cleaning blade may increase. In this case, the toner staying in the vicinity of the cleaning blade is compacted, and the compacted toner slips through the position where the cleaning blade and the photosensitive drum come into contact with each other, which may cause a cleaning failure.

Therefore, an object of the present invention is to suppress the occurrence of cleaning defects in an image forming apparatus having a cleaning means for transporting the toner recovered from the image carrier by the collecting member that comes into contact with the image carrier. ..

In the present invention, there is an image carrier that carries a toner image, an endless belt that is movable and is in contact with the image carrier, and an endless belt that is in contact with the inner peripheral surface of the belt, and the image carrier to the belt. In an image forming apparatus including a transfer member for transferring a toner image toward the belt and a collecting means for collecting the toner remaining on the belt, the collecting means comes into contact with the belt and is attached to the belt. A recovery member that recovers residual toner, the recovery member having one end fixed and the other end contacting the belt having a free end, and the rotatable toner collected by the recovery member. The belt has a stirring member for stirring, and the belt is formed on the surface on the outer peripheral surface side in contact with the recovery member along the moving direction with respect to the width direction of the belt intersecting the moving direction of the belt. A region of the recovery member that has a plurality of grooves and is in contact with the toner when viewed from the rotation axis direction of the stirring member, and is at least a part of the other end side of the recovery member with respect to the movement direction. The region overlaps with a region formed by a rotation locus of the outermost peripheral portion of the stirring member.

According to the present invention, it is possible to suppress the occurrence of cleaning defects in an image forming apparatus having a cleaning means for transporting the toner recovered from the image carrier by the collecting member that comes into contact with the image carrier.

It is schematic cross-sectional view explaining the structure of the image forming apparatus in Example 1. FIG. It is a schematic diagram explaining the structure of the collection means in Example 1. FIG. It is a schematic diagram explaining the structure of the belt in Example 1. FIG. It is a schematic diagram explaining the method of forming a groove in a belt in Example 1. FIG. It is a schematic diagram explaining the minute displacement of the recovery member in Example 1. FIG. It is a schematic diagram explaining the relationship between the groove and the recovery member in Example 1. FIG. It is a schematic diagram explaining the recovery of toner in Example 1. FIG. It is a schematic diagram explaining the contact state between a groove and a belt in Example 1. FIG. It is a schematic diagram explaining the toner transfer in Example 1, the modified example 1, and the comparative example 1. It is a schematic diagram explaining the structure of the belt in Example 2. FIG. It is a schematic diagram explaining the structure of the belt in Example 3. FIG.

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

(Example 1)
FIG. 1 is a schematic cross-sectional view showing the configuration of the image forming apparatus 100 of this embodiment. The image forming apparatus 100 of this embodiment is a so-called tandem type image forming apparatus provided with a plurality of image forming portions of Sa to Sd. The first image-forming unit Sa is yellow (Y), the second image-forming unit Sb is magenta (M), the third image-forming unit Sc is cyan (C), and the fourth image-forming unit Sd is black (Bk). ) Toners of each color form an image. These four image forming portions are arranged in a row at regular intervals, and most of the configurations of the image forming portions are substantially the same except for the color of the toner to be accommodated. Therefore, the image forming apparatus 100 of this embodiment will be described below using the first image forming unit Sa.

The first image forming unit Sa includes a photosensitive drum 1a which is a drum-shaped photosensitive member, a charging roller 2a which is a charging member, a developing means 4a, and a drum cleaning means 5a. The photosensitive drum 1a is rotationally driven in the direction of arrow R1 shown at a predetermined process speed (200 mm / sec in this embodiment). The developing means 4a has a developing container containing yellow toner, and a developing roller as a developing member for supporting the yellow toner contained in the developing container and developing a yellow toner image on the photosensitive drum 1a. The drum cleaning means 5a is a means for recovering the toner adhering to the photosensitive drum 1a. The drum cleaning means 5a includes a cleaning blade that comes into contact with the photosensitive drum 1a, and a waste toner box that stores toner and the like removed from the photosensitive drum 1a by the cleaning blade.

When the image forming operation is started by the control means (not shown) receiving the image signal, the photosensitive drum 1a is rotationally driven. During the rotation process, the photosensitive drum 1a is uniformly charged to a predetermined potential (charging potential) with a predetermined polarity (negative electrode property in this embodiment) by the charging roller 2a, and is exposed according to the image signal by the exposure means 3a. receive. As a result, an electrostatic latent image corresponding to the yellow component image of the target color image is formed. Next, the electrostatic latent image is developed by the developing means 4a at the developing position and visualized as a yellow toner image (hereinafter, simply referred to as a toner image). Here, the normal charging polarity of the toner contained in the developing means 4a is negative electrode. In this embodiment, the electrostatic latent image is reverse-developed with toner charged with the same polarity as the charging polarity of the photosensitive drum by the charging member, but in the present invention, the toner charged with the polarity opposite to the charging polarity of the photosensitive drum is used. It can also be applied to an image forming apparatus for positively developing an electrostatic latent image.

The intermediate transfer belt 10 (image carrier) as an endless and movable intermediate transfer body is arranged at a position where it comes into contact with the photosensitive drums 1a to 1d of the image forming portions Sa to Sd, and is a support that is a tension member. It is stretched by three axes of a roller 11, a tension roller 12, and an opposing roller 13. The intermediate transfer belt 10 is stretched by a tension roller 12 with a tension of a total pressure of 60 N, and moves in the direction of arrow R2 shown by the rotation of the opposing roller 13 that rotates in response to the driving force. Although details will be described later, the intermediate transfer belt 10 in this embodiment is composed of a plurality of layers.

The toner image formed on the photosensitive drum 1a applies a positive voltage from the primary transfer power source 15 to the primary transfer roller 14a in the process of passing through the primary transfer portion N1a where the photosensitive drum 1a and the intermediate transfer belt 10 are in contact with each other. As a result, the primary transfer is performed on the intermediate transfer belt 10. After that, the toner remaining on the photosensitive drum 1a without being first transferred to the intermediate transfer belt 10 is collected from the surface of the photosensitive drum 1a by the drum cleaning means 5a.

Here, the primary transfer roller 14a is a primary transfer member (contact member) that is provided at a position corresponding to the photosensitive drum 1a via the intermediate transfer belt 10 and comes into contact with the inner peripheral surface of the intermediate transfer belt 10. Further, the primary transfer power supply 15 is a power supply capable of applying a positive electrode or negative electrode voltage to the primary transfer rollers 14a to 14d. In this embodiment, a configuration in which a voltage is applied from a common primary transfer power source 15 to a plurality of primary transfer members will be described, but the present invention is not limited to this, and a plurality of primary transfer power supplies are provided corresponding to each primary transfer member. The present invention can be applied even if the configuration is provided.

Hereinafter, in the same manner, a magenta toner image of the second color, a cyan toner image of the third color, and a black toner image of the fourth color are formed and sequentially superimposed on the intermediate transfer belt 10 and transferred. As a result, a four-color toner image corresponding to the target color image is formed on the intermediate transfer belt 10. After that, the four-color toner images carried on the intermediate transfer belt 10 are supplied by the paper feeding means 60 in the process of passing through the secondary transfer portion formed by the secondary transfer roller 20 and the intermediate transfer belt 10 in contact with each other. The secondary transfer is collectively performed on the surface of the transfer material P such as paper or OHP sheet.

The secondary transfer roller 20 as a secondary transfer member, a nickel-plated steel bar having an outer diameter of 8 mm, a volume resistivity of 10 ⁸ Ω · cm, foamed sponge body mainly composed of NBR and epichlorohydrin rubber adjusted to a thickness of 5mm The one with an outer diameter of 18 mm covered with is used. The rubber hardness of the foamed sponge body was measured using an Asker hardness tester C type, and the hardness was 30 ° when a load of 500 g was applied. The secondary transfer roller 20 is in contact with the outer peripheral surface of the intermediate transfer belt 10, and a pressing force of 50 N is applied to the opposing roller 13 arranged at a position facing the secondary transfer roller 20 via the intermediate transfer belt 10. Is pressed to form the secondary transfer portion N2.

The secondary transfer roller 20 is driven to rotate with respect to the intermediate transfer belt 10, and when a voltage is applied from the secondary transfer power supply 21, a current flows from the secondary transfer roller 20 toward the opposing roller 13. As a result, the toner image supported on the intermediate transfer belt 10 is secondarily transferred to the transfer material P at the secondary transfer portion. When the toner image of the intermediate transfer belt 10 is secondarily transferred to the transfer material P, the current flowing from the secondary transfer roller 20 toward the opposing roller 13 via the intermediate transfer belt 10 is made constant. The voltage applied from the secondary transfer power supply 21 to the secondary transfer roller 20 is controlled. Here, the magnitude of the current for performing the secondary transfer is determined in advance depending on the ambient environment in which the image forming apparatus 100 is installed and the type of the transfer material P. In the configuration of this embodiment, when the toner image is secondarily transferred from the intermediate transfer belt 10 to the transfer material P, a voltage of 1800 to 2300 [V] is applied from the secondary transfer power source 21 to the secondary transfer roller 20. doing.

The transfer material P to which the four-color toner image is transferred by the secondary transfer is then heated and pressurized by the fixing means 30, so that the four-color toner is melt-mixed and fixed to the transfer material P. The toner remaining on the intermediate transfer belt 10 after the secondary transfer is cleaned and removed by the belt cleaning means 50 (recovery means) provided on the downstream side of the secondary transfer unit N2 in the moving direction of the intermediate transfer belt 10. The belt cleaning means 50 has a cleaning blade 51 as a recovery member that abuts on the outer peripheral surface of the intermediate transfer belt 10 at a position facing the opposing roller 13. In the following description, the belt cleaning means 50 is simply referred to as a cleaning means 50, and the cleaning blade 51 is simply referred to as a blade 51. Details of the configuration of the cleaning means 50 will be described later.

In the image forming apparatus 100 of this embodiment, a full-color printed image is formed by the above operation.

[Cleaning means 50]
FIG. 2A is a schematic cross-sectional view for explaining the configuration of the cleaning means 50, and FIG. 2B is a schematic diagram for explaining the configuration of the stirring member 52 provided in the cleaning means 50. Further, FIG. 2C is a schematic view illustrating a contact state between the blade 51 provided in the cleaning means 50 and the intermediate transfer belt 10. The blade 51 in this embodiment is a plate-like member that is long in the width direction (longitudinal direction of the blade 51) of the intermediate transfer belt 10 that intersects the moving direction of the intermediate transfer belt 10 (hereinafter referred to as the belt transport direction).

As shown in FIG. 3A, the cleaning means 50 includes a stirring member 52 that stirs the toner collected by the blade 51 and a transport member for transporting the toner collected by the blade 51 in the longitudinal direction of the blade 51. The screw 53 and the like. The stirring member 52 and the screw 53 are continuously provided in substantially the entire area inside the frame of the cleaning means 50 in the longitudinal direction of the blade 51. Toner can be conveyed by rotating the screw 53 by receiving a driving force from a driving source (not shown). In this embodiment, a molded screw having an outer diameter of 10 mm is used as the screw 53. ..

As shown in FIG. 2B, the stirring member 52 has a rotating shaft 52a that rotates in response to a driving force transmitted from a driving source (not shown), and a seat member 52b. The sheet member 52b is a flexible sheet member such as PET having a thickness of about 80 μm, is fixed to the rotating shaft 52a, and can rotate on the rotating shaft 52a. The rotating shaft 52a is made of a resin member having a length of 250 mm in the longitudinal direction of the blade 51, and possesses at least one flat surface portion a1 parallel to the longitudinal direction of the blade 51.

In the sheet member 52b, one end side of the sheet member 52b is fixed to the flat surface portion a1 by a double-sided tape or the like (not shown). More specifically, when viewed from the rotation axis direction of the rotation shaft 52a, one end side of the seat member 52b is fixed to the flat surface portion a1 with respect to the radial direction of the rotation locus Rm of the seat member 52b. The other end on the opposite side is the free end. In this embodiment, the length (free length Lf) of the seat member 52b that is not fixed to the flat surface portion a1 is 5 mm. The rotation locus Rm is a rotation locus of the outermost peripheral portion of the stirring member 52, that is, a rotation locus of the outermost end portion of the free end of the seat member 52b. In this embodiment, as shown in FIG. 2A, at least a part of the elastic portion 51a of the blade 51 on the free end side is located inside the circular region formed by the rotation locus Rm.

The toner recovered from the intermediate transfer belt 10 by the blade 51 is deposited in the vicinity of the blade 51 and then supplied to the screw 53 by the rotation of the stirring member 52. Then, by rotating the screw 53, the toner is conveyed toward a collection container (not shown) for collecting toner. The transfer of the toner collected by the blade 51 in the cleaning means 50 will be described in detail later.

<Structure of blade 51>
As shown in FIG. 2C, the blade 51 in this embodiment has an elastic portion 51a that contacts the intermediate transfer belt 10 and scrapes off toner, and a sheet metal portion 51b that supports the elastic portion 51a. 51a is made of polyurethane. The blade 51 has a blade shape in which the width of the elastic portion 51a in contact with the intermediate transfer belt 10 is 245 mm in length, and the elastic portion 51a and the sheet metal portion 51b are adhered to each other. The elastic portion 51a of the blade 51 has a longitudinal width of 245 mm and a thickness of 2 mm in a width direction orthogonal to the moving direction of the intermediate transfer belt 10, and has a free length of 15 mm, which is the length from the adhesion point with the sheet metal portion 51b. Is. The hardness of the blade 51 is 77 degrees according to JIS K 6253 standard.

As shown in FIG. 1, an opposing roller 13 is arranged on the inner peripheral side of the intermediate transfer belt 10 so as to face the blade 51. The blade 51 is in contact with the surface of the intermediate transfer belt 10 in the counter direction with respect to the belt transport direction at a position facing the opposing roller 13. That is, the blade 51 is in contact with the surface of the intermediate transfer belt 10 so that the elastic portion 51a has its end on the free end side in the lateral direction facing upstream with respect to the belt transport direction. Here, the free end side of the elastic portion 51a is the side of the elastic portion 51a that comes into contact with the intermediate transfer belt 10, and is the lateral direction of the elastic portion 51a when viewed from the belt width direction orthogonal to the belt transport direction. This is the other end side opposite to the one end side fixed to the sheet metal portion 51b. Further, as shown in FIG. 2C, a blade nip portion Nb is formed at a position where the blade 51 and the intermediate transfer belt 10 come into contact with each other.

In this embodiment, the blade 51 is _{arranged with respect to the intermediate transfer belt 10 so that the set angle θ a} is 20 ° and the penetration amount δ is 2.0 mm. Here, the set angle θ _a is the tangent line of the opposing roller 13 at the intersection of the intermediate transfer belt 10 and the blade 51 (more specifically, the end surface on the free end side thereof) and the blade 51 (more specifically, the thickness direction thereof). It is the angle formed by one surface that is substantially orthogonal to. Further, the penetration amount δ is the length in the thickness direction in which the blade 51 overlaps with the opposing roller 13. The contact pressure is defined by the pressing force (linear pressure in the longitudinal direction) from the blade 51 at the blade nip portion Nb, and is measured using a film type pressurizing measurement system (trade name: PINCH, manufactured by Nitta Corporation). To. By setting in this way, it is possible to suppress curling and slipping noise of the blade 51 in a high temperature and high humidity environment, and good cleaning performance can be obtained.

[Intermediate transfer belt 10]
FIG. 3 (a) is a schematic enlarged partial cross-sectional view of the intermediate transfer belt 10 cut in a direction substantially orthogonal to the belt transport direction (viewed along the belt transport direction), and FIG. 3 (b) is a schematic enlarged partial cross-sectional view. The surface layer 40 of the intermediate transfer belt 10 described later is shown in more detail in the same cross section.

The intermediate transfer belt 10 of this embodiment is an endless belt member (or film-like member) having a peripheral length of 700 mm and a longitudinal width of 250 mm and composed of two layers, a base layer 41 and a surface layer 40. Here, the base layer is defined as the thickest layer among the layers constituting the intermediate transfer belt 10 in the thickness direction of the intermediate transfer belt 10. The surface layer 40 is a layer that comes into contact with the photosensitive drums 1a to 1d and the blade 51, and is formed on the outer peripheral surface side of the intermediate transfer belt 10.

As shown in FIG. 3A, the base layer 41 of the intermediate transfer belt 10 has a thickness of 60 μm and uses an endless polyethylene terephthalate (PET) resin mixed with an ionic conductive agent as a conductive agent. The intermediate transfer belt 10 exhibits ionic conductivity as an electrical property, and the electrical conductivity is obtained by propagating ions between polymer chains. Therefore, the resistance value fluctuates with respect to the temperature and humidity of the ambient environment. However, it is characterized by good unevenness of resistance value in the circumferential direction. The surface layer 40 is made of acrylic resin and is formed on the surface of the base layer 41. In this example, the thickness of the surface layer 40 was set to 3 μm. The surface layer 40 has an action of adjusting the resistance of the intermediate transfer belt 10 and an action of adsorbing toner on the surface layer 40.

In this embodiment, in order to suppress the voltage drop in the intermediate transfer belt 10, as the resistance of the base layer 41, it was used in 1 × below 10 ⁸ Omega · cm in volume resistivity. The volume resistivity was measured by using a ring probe type UR (model MCP-HTP12) for Hiresta-UP (MCP-HT450) of Mitsubishi Chemical Corporation. The measurement conditions were an indoor temperature of 23 ° C., an indoor humidity of 50%, an applied voltage of 100 V, and a measurement time of 10 sec.

Here, the materials of the base layer 41 and the surface layer 40 are not limited to those described above, and may be other materials. For example, as the base layer 41, other than polyethylene naphthalate resin, polycarbonate, polyvinylidene fluoride (PVDF), polyethylene, polypropylene, polymethylpentene-1, polystyrene, polyamide, polysulfone, polyarylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate. , Polyphenylidene fluoride, polyether sulfone, polyether nitrile, thermoplastic polyimide, polyether ether ketone, thermotropic liquid crystal polymer, thermoplastic resins such as polyamic acid. These can be mixed and used in two or more kinds.

Regarding the surface layer 40, examples of the organic material other than the acrylic resin include curable resins such as melamine resin, urethane resin, alkyd resin, and fluorine-based curable resin (fluorine-containing curable resin). Examples of the inorganic material include alkoxysilane / alkoxyzirconium-based materials and silicate-based materials. Examples of the organic / inorganic hybrid material include an inorganic fine particle-dispersed organic polymer-based material, an inorganic fine-particle-dispersed organoalkoxysilane-based material, an acrylic silicon-based material, and an organoalkoxysilane-based material.

Further, as shown in FIGS. 3A to 3B, in this embodiment, the surface layer 40 is subjected to surface processing in order to suppress deterioration of cleanability, and is subjected to surface processing in the belt transport direction. A groove (groove shape, groove portion) 45 is formed along the groove.

As shown in FIG. 3B, the width W (hereinafter, simply referred to as width W) of the opening of the groove 45 in the direction substantially orthogonal to the belt transport direction (width direction of the intermediate transfer belt 10) is 2 μm. Further, the depth D (hereinafter, simply referred to as the depth D) from the surface (opening) where the groove of the surface layer 40 is not formed to the bottom of the groove 45 in the thickness direction of the intermediate transfer belt 10 is 2 μm. .. Further, the spacing K (hereinafter, simply referred to as pitch K) of the grooves 45 in the direction substantially orthogonal to the belt transport direction is 20 μm. From the viewpoint of cleanability, the pitch K is preferably set between 10 μm and 100 μm, typically between 10 μm and 20 μm.

The width W of the groove 45 is preferably a width up to about half of the average particle size of the toner from the viewpoint of cleanability. If the width W of the groove 45 is too wide, if the toner fits in the groove 45, it may slip through the blade nip portion Nb, resulting in poor cleaning. Further, if the width W of the groove 45 is too narrow, the contact area between the blade 51 and the intermediate transfer belt 10 becomes too large, so that the friction at the blade nip portion Nb becomes large, and the tip of the elastic portion 51a of the blade 51 becomes large. May accelerate wear. Therefore, in the configuration of this embodiment, the width W of the groove 45 is preferably set to 0.5 μm or more and 3 μm or less.

In this embodiment, since the thickness of the surface layer 40 is 3 μm, the groove 45 does not reach the base layer 41 and exists only in the surface layer 40. Further, the groove 45 is continuously formed along the circumferential direction (rotational direction) of the intermediate transfer belt 10 over the entire circumference of the intermediate transfer belt 10. In this embodiment, a mold having a convex shape on the surface is pressed against the surface layer 40 to give a groove shape to the surface of the intermediate transfer belt 10.

Here, as a means for forming the groove 45 on the surface of the intermediate transfer belt 10, means such as polishing, cutting, and imprinting can be used. The intermediate transfer belt 10 having a groove 45 on the surface in this embodiment can be obtained by appropriately selecting and using a preferable one from these forming means. Above all, from the viewpoint of processing cost and productivity, it is preferable to perform imprint processing utilizing the photocurability of acrylic resin as a base material on the surface of microfabrication. Further, the groove may be formed by performing a wrapping treatment after curing the acrylic resin. In this case, it is possible to form a groove shape on the surface of the intermediate transfer belt 10 by using a wrapping film (Lapika # 2000 (trade name), manufactured by KOVAX) or the like. Since the fine abrasive particles are uniformly dispersed in the lapping film, it is possible to impart a uniform shape without deep scratches or uneven polishing.

In this embodiment, the mold having the fine uneven shape is pressed against the surface layer 40 of the intermediate transfer belt 10, and the fine uneven shape of the mold is transferred to the surface of the intermediate transfer belt 10 by imprint processing. A groove 45 is formed on the surface of the belt 10. In this embodiment, the groove 45 is formed in the entire circumference of the intermediate transfer belt 10 along the moving direction of the intermediate transfer belt 10.

Hereinafter, the details of the imprint processing in this embodiment will be described in detail with reference to FIGS. 4 (a) to 4 (c). FIG. 4A is a schematic view showing the imprint processing apparatus from the upper side in the cylindrical axis direction of the intermediate transfer belt 10. FIG. 4B is a schematic cross-sectional view of the imprint processing apparatus cut in a direction parallel to the cylindrical axis of the intermediate transfer belt 10. FIG. 4C is a cross-sectional view of the mold 92 used for imprint processing.

When the groove 45 is formed by imprinting, first, the intermediate transfer belt 10 in which the surface layer 40 is formed on the base layer 41 is press-fitted into the core 91 (diameter 227 mm, made of carbon tool steel). Then, the intermediate transfer belt is rotated by rotating the core 91 in a state where a cylindrical mold 92 having a diameter of 50 mm and a length of 250 mm is pressed against the surface of the press-fitted intermediate transfer belt 10 with a predetermined pressing force. Processing is performed on the entire length of 250 mm of 10.

When the groove 45 is formed in the intermediate transfer belt 10, the mold 92 is heated to a temperature of 130 ° C., which is 5 to 15 ° C. higher than the glass transition temperature of polyethylene naphthalate, by a heater (not shown). Then, with the heated mold 92 in contact with the core 91, the core 91 is rotated once at a peripheral speed of 264 mm / s, and then the mold 92 is separated from the core 91. While the core 91 is being rotated, the mold 92 rotates in accordance with the rotation of the core 91. In this embodiment, the surface shape is processed as described above, and the groove 45 is formed in the surface layer 40 of the intermediate transfer belt 10.

As shown in FIG. 4C, the mold 92 of the present embodiment has a length Lk in which triangular protrusions are formed on the surface at equal intervals of Ip in parallel with the circumferential direction of the cylinder. A mold is used. The interval Ip in this example is 20 μm, and the length Lk is 250 mm. The triangular convex shape is formed by cutting so that the length of the bottom of the convex shape is 2.0 μm and the height is 2.0 μm. By performing the above-mentioned imprint processing using the mold 92 having such a shape, it is possible to obtain the intermediate transfer belt 10 having the surface shape shown in FIG.

[Recovery of toner by cleaning means 50]
By providing the intermediate transfer belt 10 with a groove shape, it is possible to reduce the contact area between the blade 51 and the intermediate transfer belt 10 and improve the wear resistance of the blade 51. This makes it possible to suppress a decrease in cleanability when the image forming apparatus 100 is operated for a long period of time.

Further, by providing the intermediate transfer belt 10 with a groove shape, the posture of the blade 51 can be made minute between the position where the groove 45 is formed and the position where the groove 45 is not formed during the rotational operation of the intermediate transfer belt 10. It can be transformed. Hereinafter, description will be made with reference to FIGS. 5 (a) to 5 (c), FIGS. 6 and 7. 5 (a) to 5 (c) are schematic views illustrating the behavior of the toner that has reached the position where the intermediate transfer belt 10 and the blade 51 come into contact with each other in this embodiment.

As shown in FIG. 5A, the toner remaining on the intermediate transfer belt 10 after passing through the secondary transfer portion N2 is blocked by the elastic portion 51a at the blade nip portion Nb where the intermediate transfer belt 10 and the blade 51 come into contact with each other. It is stopped and deposits in the vicinity of the blade 51. If the amount of toner accumulated in this state increases, the accumulated toner will be compacted. However, in the configuration of this embodiment, as shown in FIGS. 5 (b) to 5 (c), the intermediate transfer belt 10 It is possible to slightly displace the tip of the blade 51 with the rotation of the blade 51. This makes it possible to break down the toner accumulated in the vicinity of the blade nip portion Nb.

More specifically, in the position where the groove 45 is not formed, the blade 51 has the shape of FIG. 5 (a), but in the position where the groove 45 is formed, the blade 51 is shown in FIG. 5 (b). It will be the shape shown. That is, by releasing the contact with the intermediate transfer belt 10, the tip of the blade 51 is opposite to the belt transport direction at the position where the groove 45 is formed as compared with the position where the groove 45 is not formed. It is in a state of being slightly displaced in the direction of (in the direction of the arrow in the figure).

Here, the intermediate transfer belt 10 is conveyed while being slightly displaced in the width direction of the intermediate transfer belt 10. FIG. 6 describes the positional relationship between the blade 51 and the intermediate transfer belt 10 when the intermediate transfer belt 10 moves in the direction of the arrow shown from the position of the dotted line in the illustration to the position of the practice in the illustration with respect to the width direction of the intermediate transfer belt 10. It is a schematic diagram. As shown in FIG. 6, when the intermediate transfer belt 10 moves in the direction of the arrow shown in the drawing along with the rotational movement operation, the position where the groove 45 and the elastic portion 51a of the blade 51 come into contact with each other changes. That is, in the configuration of this embodiment, the intermediate transfer belt 10 rotates while being displaced with respect to the width direction of the intermediate transfer belt 10, so that the entire region of the elastic portion 51a with respect to the width direction of the intermediate transfer belt 10 becomes the groove 45. It is possible to make contact.

Therefore, the elastic portion 51a is shown in the state of FIG. 5A at the position where the groove 45 is not formed and the state of FIG. 5B at the position where the groove 45 is formed due to the rotational movement of the intermediate transfer belt 10. Both states can be taken. More specifically, as the intermediate transfer belt 10 rotates while being displaced as described above, the elastic portion 51a has the groove 45 from the state of FIG. 5B facing the position where the groove 45 is formed. It is slightly displaced to the state shown in FIG. 5 (c) facing the position where it is not formed. Then, by repeating this minute displacement with the transfer of the intermediate transfer belt 10, it is possible to break the toner accumulated in the vicinity of the blade nip portion Nb.

By forming the groove 45 on the surface of the intermediate transfer belt 10 in this way, it is possible to slightly displace the tip portion of the elastic portion 51a and break the toner accumulated in the vicinity of the blade nip portion Nb. However, if the amount of toner deposited in the vicinity of the blade nip portion Nb continues to increase, the pressure applied to the deposited toner may increase, causing a phenomenon in which the toner is gradually compacted.

Therefore, in this embodiment, the toner that has been destroyed by the minute deformation of the elastic portion 51a is conveyed to the screw 53 by the rotation of the stirring member 52, so that the toner accumulated in the vicinity of the blade nip portion Nb is compacted. Is suppressed. Hereinafter, a detailed description will be given with reference to FIGS. 7 (a) to 7 (c).

FIG. 7A is a schematic cross-sectional view for explaining a range of toner that collapses due to a minute displacement of the blade 51. FIG. 7B is a schematic cross-sectional view of the rotating shaft 52a when viewed from the direction of the rotating axis, which describes the state before the stirring member 52 scrapes the toner in the vicinity of the blade nip portion Nb. Further, FIG. 7C is a schematic cross-sectional view of the rotating shaft 52a when viewed from the direction of the rotating axis, which describes the state after the toner in the vicinity of the blade nip portion Nb is scraped off by the stirring member 52. is there.

As described above, the end portion of the elastic portion 51a on the free end side is slightly displaced with the rotational movement of the intermediate transfer belt 10, so that the toner accumulated in the vicinity of the blade nip portion Nb is destroyed. At this time, the region of the toner that collapses due to the minute displacement of the blade 51 is larger than the range Ls in the belt transport direction from the end of the elastic portion 51a that comes into contact with the accumulated toner when viewed from the rotation axis direction of the rotation shaft 52a. This is the inner area. The range Ls is determined by the pitch K of the groove 45, the contact pressure of the blade 51 with respect to _{the intermediate transfer belt 10, the set angle θ a} of the blade 51, the moving speed of the intermediate transfer belt 10, and the like. The range Ls is 1 mm. The range Ls can also be measured by photographing the behavior of the blade 51 of the blade nip portion Nb from the direction of the rotation axis of the rotation shaft 52a in a state where the intermediate transfer belt 10 is rotationally moved.

As shown in FIG. 7B, in the present embodiment, when viewed from the rotation axis direction of the rotation shaft 52a, the region formed by the rotation locus Rm of the sheet member 52b and the toner that collapses due to the minute displacement of the blade 51. Each member is arranged so as to overlap with the range Ls which is a region. In other words, it is a region of the blade 51 that comes into contact with the toner when viewed from the rotation axis direction of the rotation shaft 52a, and is at least a part of the region on the free end side of the blade 51 with respect to the belt transport direction (region in this embodiment). Rt) overlaps the region formed by the rotation locus Rm. As a result, as the stirring member 52 passes through the range Ls, as shown in FIG. 7C, a part of the toner broken by the minute displacement of the blade 51 is conveyed by the sheet member 52b and supplied to the screw 53. Will be done.

In this embodiment, since the blade 51 and the sheet member 52b are in contact with each other, the toner is conveyed by the stirring member 52 having the sheet member 52b. Further, the sheet member 52b is made of a soft member such as a PET sheet. As a result, the toner transport region of the sheet member 52b can be used to the maximum while minimizing the impact due to the contact between the blade 51 and the stirring member 52.

Here, if the stirring member 52 is brought too close to the blade 51, the length of contact of the sheet member 52b with the blade 51 becomes long, the contact time of the sheet member 52b becomes long, and the bent posture at the time of contact becomes large. .. Then, the pressure applied to the blade 51 increases due to the rotation of the stirring member 52, so that the impact received on the blade 51 increases, which may lead to a decrease in cleanability. Therefore, in this embodiment, the contact region T of the blade 51 with which the sheet member 52b comes into contact with the rotation of the stirring member 52 is set to 1 mm. In order to suppress the above-mentioned decrease in cleanability, it is more preferable to set the contact distance T to 2 mm or less.

In order to increase the amount of toner conveyed by the stirring member 52 described above, it is preferable to increase the displacement of the blade 51 due to the rotational movement of the intermediate transfer belt 10. Hereinafter, the preferred shape of the groove 45 in this embodiment will be described with reference to FIGS. 8A to 8B. FIG. 8A is a schematic view illustrating a groove shape when the displacement of the blade 51 is relatively small, and FIG. 8B is a groove shape when the displacement of the blade 51 is relatively large. It is a schematic diagram explaining.

As shown in FIG. 8A, when the groove 45 having a gentle shape is formed, the blade 51 follows the groove 45 as the intermediate transfer belt 10 rotates, so that the blade 51 and the intermediate transfer belt 10 are formed. The contact area between them becomes relatively large. As a result, the displacement of the blade 51 at the position where the groove 45 is formed becomes smaller than the shape of the blade 51 at the position where the groove 45 is not formed. On the other hand, in the shape of the groove 45 shown in FIG. 8B, the contact area between the blade 51 and the intermediate transfer belt 10 can be made smaller than that in FIG. 8A, so that the position where the groove 45 is formed is formed. The displacement of the blade 51 in the above can be made relatively large.

Here, in order to observe the contact state between the intermediate transfer belt 10 and the blade 51, the blade 51 is brought into contact with the transparent member in which each groove shape is molded so as to have a linear pressure of 80 gf / cm, and the blade 51 is brought into contact with the transparent member from the back surface. The contact state of was observed, and the results shown in Table 1 were obtained. As shown in Table 1, in order to reduce the contact area between the blade 51 and the intermediate transfer belt 10 so that the displacement of the blade 51 becomes relatively large, the depth D and width W of the groove 45 are set to D ≧ W. It is desirable to set it so as to satisfy / 2. Based on the results in Table 1, in this example, the depth D was set to 2.0 μm and the width W was set to 2.0 μm.

Further, regarding the shape of the groove 45 formed in the intermediate transfer belt 10 in this embodiment, if the depth D is too large, it becomes difficult to clean the toner that has entered the groove 45. It is preferable to set it smaller than the average particle size of the toner. In the configuration of this embodiment, since a toner having an average particle size of 6 μm is used, it is more preferable to set the depth D to 4 μm or less. Further, when the depth D is too small, the blade 51 easily follows the rotational movement of the intermediate transfer belt 10, so that the depth D is more preferably set to 0.05 μm or more.

[Action and effect]
9 (a) is a schematic diagram illustrating the configuration of the present embodiment, FIG. 9 (b) is a schematic diagram illustrating the configuration of the modified example 1 of the present embodiment, and FIG. 9 (c) is a schematic diagram. It is a schematic diagram explaining the structure of the comparative example 1 of this Example. In the modified examples 1 and the comparative example 1, the free length Lf of the seat member 152b is set shorter than the configuration of the present embodiment, the free length Lf of the seat member 152b in the modified example 1 is 4 mm, and the free length Lf in the comparative example 1 is set. The free length Lf of the seat member 252b is 2 mm. Further, as Comparative Example 2, a configuration in which the stirring member 52 is not provided was also prepared, and the cleanability in each configuration was examined.

Hereinafter, a method for examining the cleanability will be described. After continuously forming a predetermined image on 5000 sheets of transfer material P, the amount of residual toner was determined by measuring the amount of toner remaining in the vicinity of the blade nip portion Nb. Further, the operation of continuously forming a predetermined image on 5000 sheets of transfer material P was repeatedly executed, and the number of transfer materials P in which cleaning failure did not occur during this examination operation was determined.

When the free length Lf of the sheet member 52b becomes short, the toner transport region by the stirring member 52 becomes narrow. Therefore, among the toner deposited in the vicinity of the blade nip portion Nb, the amount of toner that cannot be conveyed by the stirring member 52 increases. Table 2 is a table showing the weight of the toner remaining in the vicinity of the blade nip portion Nb and the number of transfer materials P in which cleaning defects did not occur (hereinafter referred to as the number of cleanable sheets) in each configuration. ..

In the configuration of this example, the amount of residual toner was 1.9 g, and no cleaning failure was confirmed even after forming a predetermined image on 30,000 transfer materials P. In the configuration of the modified example 1 in which the free length Lf is shorter than that of the present embodiment, the amount of residual toner is 2.4 g, which is larger than that of the present embodiment, but the number of cleaning sheets is the same as that of the present embodiment. ..

On the other hand, in the configuration of Comparative Example 1 in which the free length Lf is shorter than that of Modified Example 1, the amount of residual toner increased to 3.5 g. Further, the number of sheets to be cleaned was also reduced to 12000, and after forming a predetermined image on the transfer material P of 12000 sheets, the toner that passed through the blade nip portion Nb was confirmed on the image of the transfer material P, and a cleaning failure occurred. .. Further, in the configuration of Comparative Example 2 in which the stirring member 52 was not provided, the amount of residual toner increased to 4.2 g and the number of cleaning sheets decreased to 3000.

This is different from the present embodiment and the first modification in which the range Ls in which the blade 51 is minutely displaced and the rotation locus Rm of the seat member 52b overlap, and in the comparative example 1, the range Ls in which the blade 51 is minutely displaced and the seat member 52b are This is because the rotation locus Rm does not overlap. In Comparative Example 1, the blade 51 is slightly displaced due to the formation of the groove 45, but it is difficult for the sheet member 52b to convey the toner that has collapsed due to the minute displacement of the blade 51. A decrease was confirmed. Further, in Comparative Example 2, since the stirring member 52 is not provided, the toner accumulated in the vicinity of the blade nip portion Nb cannot be conveyed to the screw 53, and cleaning failure occurs more than in Comparative Example 1. confirmed.

As described above, in the configuration of the present embodiment, by providing the groove 45 in the intermediate transfer belt 10, the blade 51 can be slightly displaced with respect to the belt transport direction as the intermediate transfer belt 10 rotates and moves. is there. Further, in the present embodiment, since the range Ls in which the blade 51 is minutely displaced and the rotation locus Rm of the sheet member 52b overlap, the toner collapsed due to the minute displacement of the blade 51 is screwed by the rotation of the stirring member 52. It can be transported to 53.

Further, in the present embodiment, the region of the blade 51 that comes into contact with the toner when viewed from the rotation axis direction of the rotation shaft 52a, that is, at least a part of the region on the free end side of the blade 51 with respect to the belt transport direction. , It has a structure that overlaps the region formed by the rotation locus Rm. As a result, the contact region T in which the elastic portion 51a of the blade 51 and the sheet member 52b are in contact with each other is formed, so that the stirring member 52 can more efficiently convey the toner to the screw 53. As a result, it is possible to achieve further suppression of deterioration in cleanability.

In this embodiment, the configuration having the sheet member 52b as the stirring member 52 has been described, but if the member has a configuration capable of transporting toner in the vicinity of the blade 51 and the impact on the blade 51 does not become excessive, this can be used. Not exclusively. For example, a rotating brush member or the like may be used as the stirring member 52. In this case, the same effect as in this embodiment can be obtained by making the rotation locus of the outermost circumference of the brush member overlap with the range Ls.

(Example 2)
In the first embodiment, the intermediate transfer belt 10 rotates while being slightly displaced in the width direction of the intermediate transfer belt 10, so that the entire region of the elastic portion 51a in the width direction of the intermediate transfer belt 10 comes into contact with the groove 45. The configuration that makes this possible has been described. On the other hand, the second embodiment is different from the first embodiment in that, as shown in FIG. 10, the groove 245 along the moving direction of the intermediate transfer belt 210 is provided diagonally with respect to the moving direction of the intermediate transfer belt 210. .. In the following description, the same configurations and controls as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 10 is a schematic view illustrating the relationship between the groove 245 formed on the surface of the intermediate transfer belt 210 and the blade 51 in this embodiment. _{As shown in FIG. 10, the intermediate transfer belt 210 forms an angle θ b} on the surface (surface layer) of the intermediate transfer belt 210 with respect to the virtual line VL drawn with respect to the moving direction of the intermediate transfer belt 210, and the intermediate transfer belt 210 A plurality of grooves 245 extending along the moving direction of the above are provided. Here, θ _b = 1.5 °, and the grooves 245 are formed at an interval I of 18 mm in the width direction intersecting the moving direction of the intermediate transfer belt 210. In this embodiment, the distance I between the adjacent grooves is set so as to satisfy the following equation 2 by using the circumference L of the intermediate transfer belt 210 and the angle θ _b.

I ≦ L × tan θ _b ... (Equation 2)
As shown in FIG. 10, the interval I of the grooves 245 in the width direction of the intermediate transfer belt 210 orthogonal to the moving direction of the intermediate transfer belt 210 is set to a value satisfying Equation 1. As a result, the entire region of the elastic portion 51a of the blade 51 can face the groove 245 in the width direction of the intermediate transfer belt 210 while the intermediate transfer belt 210 orbits are overlapped. As a result, according to the configuration of the present embodiment, the minute displacement of the blade 51 described in the first embodiment occurs in the entire region of the blade 51 with the rotational movement of the intermediate transfer belt 210, so that the entire region of the blade 51 The effect of toner breaking can be obtained stably.

As described above, according to the configuration of the present embodiment, in the configuration in which the intermediate transfer belt 210 does not move in the width direction of the intermediate transfer belt 210, that is, in the configuration in which the movement of the intermediate transfer belt 210 in the width direction is restricted. It is also possible to obtain the same effect as in Example 1.

Further, as compared with Example 1, in this example, regardless of the presence or absence of movement of the intermediate transfer belt 210 in the width direction, at the interval I where the groove 245 is formed with the rotational movement of the intermediate transfer belt 210. The minute displacement of the blade 51 is repeated. That is, at each point of the blade 51, the state of contact with the groove 245 and the state of not contacting the groove 245 are alternately repeated at regular intervals (interval I). Therefore, since the minute displacement of the blade 51 is performed more finely, the operation of breaking the toner accumulated in the vicinity of the blade nip portion Nb is frequently performed. As a result, in the configuration of the present embodiment, not only the same effect as that of the first embodiment can be obtained, but also the toner can be more effectively decomposed than that of the first embodiment, so that the stirring member 52 increases the amount. Toner can be conveyed to the screw 53.

(Example 3)
FIG. 11 is a schematic view illustrating the configuration of the intermediate transfer belt 310 in the third embodiment. In this embodiment, as a method of deforming the posture of the blade 51, regions having different intervals of the grooves 345 are created. In the following description of the third embodiment, the same components and controls as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

Specifically, in the configuration of this embodiment, as shown in FIG. 11, a region X having a narrow space between the partial grooves 345 is provided on the intermediate transfer belt 310. The region X is a region provided for a certain distance with respect to the moving direction of the intermediate transfer belt 310 (the direction orthogonal to the width direction of the intermediate transfer belt 310 in the drawing). Further, with respect to the moving direction of the intermediate transfer belt 310, in the regions other than the region X, the distance between the adjacent grooves 345 is set wider than that in the region X.

In the configuration of the present embodiment, when the blade 51 passes through the region X, the gap between the grooves 345 is narrow, so that minute displacement of the blade 51 occurs more frequently than when passing through a region other than the region X. To do. That is, when the blade 51 passes through the region X, the operation of breaking the toner accumulated in the vicinity of the blade nip portion Nb is frequently performed. Further, by providing the region X in which the intervals of the grooves 345 are different between the circumferences of the intermediate transfer belt 310, the frequency of minute displacements of the blade 51 increases at regular intervals while the intermediate transfer belt 310 rotates once, and the toner is broken. The state in which the effect of is high can be expressed at regular intervals. As described above, in the configuration of the present embodiment, not only the same effect as that of the first embodiment can be obtained, but also the toner can be broken down more effectively than that of the first embodiment, so that the stirring member 52 It is possible to transfer more toner to the screw 53.

Here, as a method of creating the narrowly spaced regions X of the grooves 345, after forming the equally spaced grooves 345 on the intermediate transfer belt 310 as in the first embodiment, the same groove mold is formed again at equal intervals. There is a method of forming and providing the groove 345 between the grooves. Further, the present invention is not limited to this, and the region X may be formed by using a mold in which the distance between the grooves 345 is partially narrowed.

Specifically, in this embodiment, the distance between the adjacent grooves 345 in the region X is 10 μm, and the distance between the adjacent grooves 345 in the regions other than the region X is 20 μm. As a method for creating the grooves 345, first, a mold having protrusions at intervals of 20 μm is pressed against the intermediate transfer belt 310 to form a region having a groove interval of 20 μm. Then, using the same mold, the region X having a groove spacing of 10 μm is formed by pressing the mold with the width direction of the intermediate transfer belt 310 shifted by 10 μm from the position where the groove 345 is formed. Formed.

Here, in this embodiment, 20 μm and 10 μm have been described as examples of the groove 345 spacing, but the present invention is not limited to this, and wider spacing or narrower spacing may be formed on the intermediate transfer belt 310. .. Further, a region without a groove may be provided on the intermediate transfer belt 310, and the posture of the blade 51 may be deformed in that region.

Further, as a method of forming the region X, when the same groove mold is pressed against the intermediate transfer belt 310, the region X may be formed by forming the groove so that the start point and the end point at which the mold is pressed overlap. Good. For example, when an oblique groove as in the second embodiment is provided, the inclination angle is set so that the groove shapes do not completely overlap after one round, and the groove region of a certain distance (for example, 100 mm) with the circumference of the intermediate transfer belt in the mold. Should be provided. As a result, it is possible to provide a narrow region in which the groove shapes do not overlap and the groove spacing is different for a certain distance. In such a groove shape, in addition to the shape of the diagonal groove of the second embodiment, both regions having different groove spacings can be provided. Therefore, both the blade 51 performing uniform posture deformation in the rotation direction and the vertical longitudinal direction of the intermediate transfer belt and increasing the effect of the posture deformation can be achieved, which is a very effective method. ..

In Examples 1 to 3, the image forming apparatus 100 of the intermediate transfer method using the intermediate transfer belt has been described, but the present invention is not limited to this. Even in a direct transfer type image forming apparatus having a transport belt for transporting the transfer material P, the same effects as in Examples 1 to 3 can be obtained by adopting the configurations and controls described in Examples 1 to 3. It is possible.

1 Photosensitive drum 10 Intermediate transfer belt 14 Primary transfer roller 45 Groove 50 Cleaning means 51 Cleaning blade 52 Stirring member

Claims (13)

An image carrier that carries a toner image, an endless belt that is movable and is in contact with the image carrier, and a toner that comes into contact with the inner peripheral surface of the belt and is directed from the image carrier toward the belt. In an image forming apparatus including a transfer member for transferring an image and a collecting means for recovering toner remaining on the belt.
The recovery means is a recovery member that recovers toner remaining on the belt in contact with the belt, and has a recovery member having one end fixed and the other end in contact with the belt free end. It has a stirring member that is rotatable and that stirs the toner collected by the collecting member.
The belt has a plurality of grooves formed along the moving direction with respect to the width direction of the belt intersecting the moving direction of the belt on the surface on the outer peripheral surface side in contact with the collecting member.
When viewed from the direction of the rotation axis of the stirring member, at least a part of the region of the recovery member with which the toner comes into contact, which is the other end side of the recovery member in the moving direction, is the region of the stirring member. An image forming apparatus characterized in that the rotation locus of the outermost peripheral portion overlaps with a region formed. The image forming apparatus according to claim 1, wherein the collecting member is a cleaning blade that is brought into contact with the moving direction of the image carrier in a counter direction. The stirring member has a rotatable rotating shaft and a flexible sheet member whose one end side is fixed with respect to the rotating shaft and whose other end side is a free end, and the rotation locus is the said. The image forming apparatus according to claim 1 or 2, wherein the rotation locus is the end of the free end of the sheet member. The collecting means includes a transporting member capable of transporting toner in the width direction of the belt, and the toner recovered from the belt by the collecting member is directed toward the transporting member by rotation of the stirring member. The image forming apparatus according to any one of claims 1 to 3, wherein the image forming apparatus is transported. The plurality of grooves are formed obliquely with respect to the moving direction at an angle θ _b along the moving direction, and the width thereof is defined as a circumference L which is a length related to the moving direction. The image forming apparatus according to any one of claims 1 to 4, wherein the distance I between adjacent grooves satisfies the following formula in terms of direction.
I ≦ L × tan θ _b The belt is composed of a plurality of layers, and is characterized by having a base layer, which is the thickest layer among the plurality of layers, and a surface layer formed on the surface of the belt, which is in contact with the image carrier. The image forming apparatus according to any one of claims 1 to 5. A claim characterized in that the belt has a first region in which the groove is formed and a second region in which the distance between the grooves formed is different from that of the first region in the moving direction. Item 6. The image forming apparatus according to any one of Items 1 to 6. The belt is an intermediate transfer belt, and the toner image carried on the image carrier is primarily transferred from the image carrier to the intermediate transfer belt and then secondarily transferred from the intermediate transfer belt to the transfer material. The image forming apparatus according to any one of claims 1 to 7. A toner image primary transferred from the image carrier to the intermediate transfer belt at a position where the secondary transfer member abuts on the outer peripheral surface of the intermediate transfer belt and the secondary transfer member and the intermediate transfer belt come into contact with each other. Is secondarily transferred to the transfer material,
The collecting means is arranged on the downstream side of the position where the secondary transfer member and the intermediate transfer belt come into contact with each other and on the upstream side of the transfer portion with respect to the moving direction of the intermediate transfer belt. The image forming apparatus according to claim 8. A first tensioning member and a second tensioning member for tensioning the intermediate transfer belt are provided.
The image forming apparatus according to claim 9, wherein the secondary transfer member is arranged at a position facing the first tension member via the intermediate transfer belt. The image forming apparatus according to claim 10, wherein the recovery member is arranged at a position facing the first tension member via the intermediate transfer belt. The belt is a transport belt for transporting a transfer material, and the toner image carried on the image carrier is sequentially superimposed on the transfer material transported by the transport belt and transferred. The image forming apparatus according to any one of 7 to 7. An image carrier that carries a toner image, an endless belt that is movable and is in contact with the image carrier, and a toner that comes into contact with the inner peripheral surface of the belt and is directed from the image carrier toward the belt. In an image forming apparatus including a transfer member for transferring an image and a collecting means for recovering toner remaining on the belt.
The recovery means is a recovery member that recovers toner remaining on the belt in contact with the belt, and has a recovery member having one end fixed and the other end in contact with the belt free end. It has a stirring member that is rotatable and that stirs the toner collected by the collecting member.
The recovery member is slightly displaced in the moving direction of the belt with the rotational movement of the belt, and the other end side of the recovery member is slightly displaced when viewed from the rotation axis direction of the stirring member. An image forming apparatus characterized in that a region where the toner collapses in the vicinity of the recovery member overlaps with a region formed by a rotation locus of the outermost peripheral portion of the stirring member.

Images