JP2017097321A - Photoconductor foreign matter removing mechanism, process unit, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove fixed foreign matter on a photoconductor generated from an edge of a spacer member of an optical writing head near both ends in a width direction of a toner thin layer region. A foreign matter removing mechanism for removing foreign matter including toner remaining at an axial end portion on a photoconductor 108. The foreign matter removing member 71, which is in sliding contact with the surface of the photoconductor 108 and scrapes off the fixed foreign matter, is inserted into the widthwise end of the toner thin layer region L3 from the inner end of the spacer member 51 of the optical writing head 103. It is arranged so as to cross an extension line extending to the upstream side or the downstream side in the circumferential direction of 108. [Selection diagram] Fig. 4

Description

The present invention relates to a foreign matter removing mechanism for a photoreceptor that removes foreign matter on the surface of a photoconductor provided with an optical writing head, a process unit having the foreign matter removing mechanism, and an image forming apparatus.

An image forming apparatus such as a printer, a copier, a facsimile, or a composite machine of these includes a cleaning blade that cleans residual toner remaining on a photosensitive member carrying an electrostatic latent image and a toner image. However, in the vicinity of the edge of the maximum sheet width, foreign matters in which transfer residual toner or silica as a free substance from the toner is mixed with paper dust and talc components from the sheet are likely to adhere (fix).

The foreign matter is difficult to remove with a cleaning blade, and damages the edge of the cleaning blade. Then, the foreign matter is transferred as a streak-like image or a granular image due to toner dropping near the edge in the width direction of the paper, thereby causing an image defect.

Therefore, in Patent Document 1 (Japanese Patent Laid-Open No. Sho 61-120181) and Patent Document 2 (Japanese Patent Laid-Open No. 2004-252030), toner for cleaning is preferentially attached in the vicinity of the maximum paper width to remove the foreign matter. Techniques for removal have been proposed. However, there is a problem in the related art that the exposure width of the optical writing head is increased to increase the size of the apparatus, increase the cost, increase the toner consumption for cleaning, and remove the foreign matter beyond the maximum exposure width.

For example, Patent Document 3 (Japanese Patent Application Laid-Open No. 2015-108645), Patent Document 4 (Japanese Patent Application Laid-Open No. 2015-31708), and Patent Document 5 (Japanese Patent Application Laid-Open No. 2005-2005) are known as techniques for removing foreign matters in portions exceeding the maximum exposure width. 141109) and Patent Document 6 (Japanese Patent Application Laid-Open No. 2004-045771) have been proposed. In Patent Document 3 (Japanese Patent Laid-Open No. 2015-108645), a foreign matter removing member is arranged separately from the cleaning blade in a form straddling the edge of the toner thin layer outside the maximum exposure width. In Patent Document 4 (Japanese Patent Laid-Open No. 2015-31708), a spacer member that determines the distance between the photosensitive member and the optical writing head has a foreign substance removing function. Patent Document 5 (Japanese Patent Laid-Open No. 2005-141109) provides a second polishing member for photoconductor polishing. In Patent Document 6 (Japanese Patent Application Laid-Open No. 2004-045771), a polishing sheet is sandwiched between a photosensitive member and a cleaning blade to polish and remove discharge products.

In the technique of Patent Document 4 (Japanese Patent Laid-Open No. 2015-31708), the spacer member is made of a material such as polyacetal (POM) that has good slidability so that foreign matter does not bite into the contact surface of the spacer member with respect to the photosensitive member. Has been. However, if the contact pressure of the spacer member is weak, the fixed object removing function is lowered and a vertical stripe image is generated.

On the other hand, if the contact pressure of the spacer member is strong, the film thickness of the photoconductor is worn by the spacer member, and the wear accuracy decreases the positioning accuracy of the optical writing head, or streaks due to wear failure at the end of the life. The image is generated. Another problem is that foreign matter overflowing from the edge of the spacer member that comes into contact with the photoconductor causes new fixed foreign matter to start from the edge.

SUMMARY OF THE INVENTION An object of the present invention is to provide a foreign matter removing mechanism capable of removing a sticking foreign matter on a photoconductor generated from the edge of a spacer member of an optical writing head near both ends in the width direction of a toner thin layer region.

In order to solve the above-mentioned problem, the present invention sets the maximum paper width that can be passed through and the maximum exposure width inside the maximum paper width inside the width direction of the toner thin layer region formed in the circumferential direction, A photosensitive member carrying an electrostatic latent image and a toner image within the region of the maximum exposure width, and a pair of inner end portions that are disposed at both ends in the axial direction of the photosensitive member and face each other are the toner thin layer regions. Light that is positioned on the surface of the photoconductor through a spacer member that is slidably contacted with the surface of the photoconductor so as to bite into both ends in the width direction, and that exposes the surface of the photoconductor to form the electrostatic latent image A writing head; a developing member that forms a toner image by supplying a toner thin layer as a developer to the toner thin layer region on the surface of the photoconductor after exposure; and a development that remains on the surface of the photoconductor Image forming apparatus having cleaning member for removing agent Use the photoconductor to remove foreign matter including toner remaining on the axial end of the photoconductor after the toner image on the photoconductor is transferred to a paper or intermediate transfer material as a transfer material. In the removing mechanism, a foreign matter removing member that slides in contact with the surface of the photosensitive member and scrapes off the foreign matter that adheres to the surface of the photosensitive member from the inner end portion of the spacer member that bites into the widthwise end portion of the toner thin layer region A foreign matter removing mechanism for a photosensitive member, wherein the foreign matter removing mechanism is disposed so as to cross an extension line extending upstream or downstream in the circumferential direction of the body.

According to the present invention, the foreign matter removing member crosses the extension line extending from the inner end portion of the spacer member biting into the width direction end portion of the toner thin layer region to the upstream side or the downstream side in the circumferential direction of the photosensitive member. Since it is arranged, it is possible to remove the adhering foreign matter on the photoconductor generated from the edge of the spacer member of the optical writing head near the end of the toner thin layer region.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. It is a schematic block diagram of the process unit which concerns on this embodiment. (A) and (b) are schematic sectional drawings of an image forming device. It is a schematic block diagram of an optical writing head positioning mechanism. (A) And (b) is a perspective view of a spacer member, (c) is a bottom view of a spacer member. It is a figure similar to FIG. 5A which made the columnar part cylindrical. (A) (b) is a figure which shows the state in which a stripe-like foreign material generate | occur | produces from the edge part of a spacer member. It is a figure which shows the preferable positional relationship of a spacer member and a removal member. It is a figure which shows the undesirable positional relationship of a spacer member and a removal member. It is a figure which shows the 1st example of arrangement | positioning of the foreign material removal member of a photoconductor. It is a figure which shows the 2nd example of arrangement | positioning of the foreign material removal member of a photoconductor. It is a perspective view which shows the attachment structure of the foreign material removal member of a photoconductor. It is a side view which shows the attachment structure of the foreign material removal member of a photoconductor. It is a schematic sectional drawing which shows the deformation | transformation embodiment which changed the attachment position and attachment structure of the foreign material removal member of a photoconductor. It is a figure which shows the example of arrangement | positioning of the foreign material removal member of FIG. It is a figure which shows the modification of the example of arrangement | positioning of the foreign material removal member of FIG. It is a figure which shows the example of arrangement | positioning of the foreign material removal member in the case of using an optical scanning device. It is a figure which shows the deformation | transformation embodiment which changed the shape and arrangement | positioning of the foreign material removal member of FIG. 11A. It is a figure which shows the deformation | transformation embodiment which changed the shape and arrangement | positioning of the foreign material removal member of FIG. 11C. It is a figure which shows the attachment structure of the foreign material removal member of FIG. It is a figure which shows other embodiment of a foreign material removal member. It is sectional drawing of FIG. 14A. (A) is a perspective view of the holding member of the foreign matter removing member, (b) is a perspective view of the cleaning blade holder, (c) is a perspective view of the cleaning blade holder attached with a spring, and (d) is a holding member of the foreign matter removing member. It is a perspective view of the cleaning blade holder of the state which attached to the spring. It is a schematic sectional drawing of the process unit which supported the foreign material removal member via the flat plate spring. It is a schematic sectional drawing of the process unit which supported the foreign material removal member via the bent leaf | plate spring. It is sectional drawing which shows the specific attachment structure of the leaf | plate spring with respect to the cleaning blade holder in a process unit. It is a side view which shows the assembly | attachment procedure of a leaf | plate spring schematically. It is a schematic sectional drawing which shows the state which assembled | attached the leaf | plate spring in the process unit. (A)-(d) is a figure explaining the attachment structure of the leaf | plate spring with respect to a process unit.

Hereinafter, an embodiment of a foreign matter removing mechanism for a photoreceptor according to the present invention will be described with reference to the accompanying drawings. In the drawings for explaining the present invention, components such as members and components having the same function or shape are denoted by the same reference numerals as much as possible, and once described, the description will be given. Omitted.

(Schematic configuration of image forming apparatus)
FIG. 1 is a schematic configuration diagram illustrating an example of an electrophotographic image forming apparatus including a photoreceptor foreign matter removing mechanism according to an embodiment of the present invention. This image forming apparatus is a general tandem color image forming apparatus.

In the main body of the image forming apparatus 100, the process units 102b to 102d of three colors (for example, cyan, magenta, and yellow) are detachably mounted following the black process unit 102a for monochrome. Here, “a”, “b”, “c”, and “d” next to the reference numbers indicate parts related to the respective process units of black, cyan, magenta, and yellow. However, in the following description, when components common to each color are described, a to d are omitted as appropriate and only numbers are described.

In the main body of the image forming apparatus 100, an optical writing head 103, transfer rollers 101a to 101d, a paper feed tray 104, a fixing device 106, and the like are disposed. Each process unit 102 a to 102 d has an exterior case 1021 as shown in FIG. 2, and the photoreceptor 108 and the like are accommodated in the exterior case 1021. The photoreceptor 108 is cylindrical, and as an example, rotates in the clockwise direction at a linear speed of 150 mm / s.

As shown in FIGS. 3 and 4, support shafts 1081 are provided at both ends of the photoconductor 108, and the support shafts 1081 protrude from the exterior case 1021 to the outside and are rotatably supported by bearings on the main body side of the image forming apparatus 100. ing. A driven gear 1082 disposed on the outer periphery of one end of the photoconductor 108 is engaged with a driving gear connected to the motor shaft on the main body side.

As shown in FIGS. 2 and 3, a roller-shaped charger 110 serving as a charging unit is pressed against the surface of the photoreceptor 108, and the charger 110 is driven to rotate by the rotation of the photoreceptor 108. ing. Then, a DC bias (or AC superimposed on DC) bias is applied to the charger 110 from a high voltage power source, so that the photosensitive member 108 is charged to a substantially uniform surface potential and initialized.

In the photoconductor 108, image information is exposed by the optical writing heads 103a to 103d, and as a result, a low potential portion where the potential is attenuated by the exposure is formed on the peripheral surface of the photoconductor 108 charged to the uniform high potential. And an electrostatic latent image formed by the initialization and the high potential portion. A developing roller 111 as a developing unit is disposed around the photoconductor 108, and a high voltage power source is connected to the developing roller 111.

Then, the electrostatic latent image is transferred to the low potential portion of the electrostatic latent image on the photosensitive member 108 by a predetermined developing bias supplied from the high voltage power source, for example, a negative developing bias voltage. It has come to be visualized as an image. Above the developing roller 111, a developer container that contains the one-component toner necessary for the visualization is disposed.

Four process units 102a to 102d are arranged in parallel, and an intermediate transfer belt 120 is arranged below the process units 102a to 102d. The intermediate transfer belt 120 can be separated from each photoconductor 108 at an arbitrary timing by a contact / separation mechanism.

Examples of the material of the intermediate transfer belt 120 include PVDF (vinylidene fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), PI (polyimide), PC (polycarbonate), TPE (thermoplastic elastomer), and carbon. A resin film-like endless belt in which a conductive material such as black is dispersed is used.

The intermediate transfer belt 120 is stretched around a tension roller 121, a driving roller 122, and a plurality of transfer rollers 101. Then, the driving roller 122 is rotationally driven by the driving motor, so that the intermediate transfer belt 120 is driven to rotate in the direction of the arrow. A transfer electric field is formed on the transfer roller 101 by applying a predetermined transfer bias independent of each color from a high voltage power source.

A toner density detection unit 126 is disposed in the intermediate transfer belt 120 at a position closest to the tension roller 121. The toner density detecting means 126 is an optical sensor composed of a regular reflection type sensor and a diffuse reflection type sensor. The toner density detection means 126 detects the amount of reflected light of the image and toner patch formed on the photoconductor 108 and then transferred to the intermediate transfer belt 120.

Then, the toner density or adhesion amount is detected based on the reflected light amount, and the detected toner adhesion amount is fed back to the development control means 131 described later to determine the image forming conditions. The toner density detecting means 126 may be disposed on the outer periphery of each photoconductor 108.

On the other hand, a sheet as a transfer material is stored in a paper feed tray 104. Then, in accordance with the timing at which the front end of the toner image on the photoconductor 108 reaches the transfer portion between the tension roller 121 and the secondary transfer roller 125, the sheet is transferred to the transfer portion by the paper feed roller 105 and the timing roller pair 107. To be sent to. The secondary transfer roller 125 is configured by covering an elastic body with a conductive material on a metal core.

When a full color image is formed by the image forming apparatus, visible images are formed in the order of yellow, cyan, magenta, and black from the right to the left in the figure. The visible images of the toner images of the respective colors on the photoconductor 108 are sequentially transferred onto the intermediate transfer belt 120 with the transfer roller 101, so that a full color image is formed on the intermediate transfer belt 120.

The image is transferred onto a sheet at a transfer portion between the tension roller 121 and the secondary transfer roller 125. The sheet onto which the image has been transferred is then subjected to heat and pressure by the fixing device 106 to fix the image, and is then discharged out of the device.

The transfer residual toner remaining on the intermediate transfer belt 120 that has passed through the tension roller 121 is collected by the cleaning blade 123. The collected transfer residual toner is stored in the waste toner storage unit 124 through the toner conveyance path.

The optical writing heads 103a to 103d of each process unit collect LED elements or organic EL elements having a desired number of pixels (image width × pixel density 1200 dpi) as the light emitting elements 1031, their drive circuits, and light emitted by the elements. It has a lens array that shines. These are incorporated in a housing to constitute an LED head or an organic EL head.

Each element emits light according to an image signal, and a latent image is formed on the photoconductor 108. The lens array has a large numerical aperture and a short focal length in order to efficiently secure the amount of emitted light. Therefore, the head is installed close to the photoconductor (a proximity position of several mm from the photoconductor).

A shape (hole, protrusion, plane, etc.) for mounting the head is formed on the casing. A harness for supplying an image signal in accordance with a power source and image data is coupled to the head.

In the main body of the image forming apparatus 100, development control means 131 is disposed. A temperature sensor 132 and a humidity sensor 133 are connected to the development control means 131, and the temperature and humidity in the apparatus are detected by these sensors 132 and 133, and the measured values are taken into the development control means 131. The development control unit 131 is configured to calculate an absolute humidity amount in the apparatus from the captured temperature value and humidity value, and to calculate a charging bias and a surface potential of the photoconductor based on the absolute humidity.

The tandem color image forming apparatus has been described above as an example, but the present invention can also be applied to a 4-cycle color image forming apparatus and a monochrome image forming apparatus. Further, a developing method using a two-component toner instead of the one-component toner may be employed.

(Process unit)
FIG. 2 shows a schematic diagram of the process unit 102 as an image forming apparatus. The process unit 102 includes an upper toner supply container 201 that stores toner for replenishment, and a lower developing chamber 203 that stores a predetermined amount of toner from the beginning. In the toner supply container 201, a stirring paddle 208 or the like may be disposed in order to constantly stir the toner and maintain its fluidity.

Inside the toner supply container 201, a conveying unit 202 such as a screw or a coil is disposed along with the stirring paddle 208. The transport unit 202 is configured to be connectable to a main body drive unit via a known contact / separation unit such as a clutch, and the toner supply container 201 is replenished by driving the transport unit 202 as necessary. It has become.

The toner replenishment amount can be controlled by the drive time of the main body drive unit. For example, it is possible to perform control such as changing the driving time in response to the change in toner fluidity in a temperature and humidity environment.

A toner transporting member 205 such as a screw is disposed in the developing chamber 203 disposed at the lower part of the process unit 102 to transport the toner replenished from the upper toner supply container 201 to the entire longitudinal direction. Yes. In addition, an agitator 204 for agitating the toner is disposed adjacent to the toner transport member 205.

The draft level of the remaining amount of toner in the developing chamber 203 is detected by a remaining amount detection sensor 211. The remaining amount detection sensor 211 may be a light transmission type sensor, a piezoelectric sensor, or a mechanical detection sensor. When the remaining amount of toner in the developing chamber 203 falls below the sensor detection surface, the toner supply from the toner supply container 201 is performed.

At the bottom of the developing chamber 203, a developing roller 111, which is a toner carrier, and a supply roller 206 that supplies toner to the developing roller are disposed. The supply roller 206 is mainly made of a sponge material.

A developing bias is applied to the developing roller 111 by a developing bias applying unit 212. A supply bias is applied to the supply roller 206 by a supply bias application unit 213. The development bias applying unit 212 and the supply bias applying unit 213 are controlled by the control unit 130.

The developing roller 111 is disposed in a non-contact state with respect to the photoconductor 108 and develops the electrostatic latent image on the surface of the photoconductor 108 with toner in a non-contact manner. The developing roller 111 can be placed in contact with the photosensitive member 108 for contact development.

The toner moved to the developing roller 111 by the supply roller 206 is made uniform on the toner layer adhering to the surface of the developing roller 111 by the regulating blade 207, and then an amount of toner corresponding to the surface potential of the photosensitive member 108 is transferred to the photosensitive member 108. Move to the surface. The toner image developed with the toner moved to the surface of the photoconductor 108 is then transferred to the intermediate transfer belt 120 through the primary transfer nip.

Residual toner on the developing roller 111 that has not moved to the photoconductor 108 is rubbed against the toner leakage prevention sheet 210 disposed in the gap around the developing roller 111 and then collected into the developing chamber 203. .

The toner that has moved to the photoconductor 108 but remains on the photoconductor 108 as a transfer residual toner passes through the seal member 82 and is removed by the cleaning blade 209, and then is transferred to the image forming apparatus by the toner transport member 214 such as a screw. The waste toner is stored in the waste toner storage unit 124 in 100.

The sheet on which the toner image has been transferred is conveyed to the fixing device 106 and heated and pressurized by passing through the fixing nip between the fixing roller 106a and the pressure roller 106b, and the toner image on the sheet is fixed. Is done. The paper is then discharged out of the apparatus by the paper discharge roller 112 and placed on the paper discharge tray 113.

(Spacer member for positioning optical writing head)
As described above, the optical writing head 103 uses an LED or an organic EL element as the light emitting element 1031. Since the light emitting element 1031 has a shallow depth of focus (about 100 μm), it is necessary to determine the position of the optical writing head 103 with respect to the photosensitive member 108 with high accuracy.

Therefore, the process unit 102 is provided with a spacer member 51 for positioning the optical writing head 103 with respect to the photoreceptor 108. Hereinafter, the spacer member 51 will be described with reference to FIGS.

As shown in FIGS. 3A and 3B, the spacer member 51 contacts the surface of the photoconductor 108 and the lower surface of the optical write head 103, thereby positioning the optical write head 103 with respect to the photoconductor 108. It plays a role in regulating and determining the distance between them. FIGS. 3A and 3B are different in the position of a foreign substance removing member 71 described later, and the rest of the configuration is the same.

As shown in FIG. 4, the optical writing head 103 is arranged extending in the axial direction (main scanning direction) of the photoconductor 108. An LED element or an organic EL element having a desired number of pixels (image width × pixel density 1200 dpi) is disposed on the lower surface of the optical writing head 103 as the light emitting element 1031.

The spacer members 51 are disposed on both ends in the longitudinal direction of the optical writing head 103 or in the axial direction of the photosensitive member 108, and are in contact with the lower surface of the optical writing head 103 and the surface of the photosensitive member 108, respectively. In a state where the spacer member 51 is in contact with both the photoconductor 108 and the optical writing head 103, the spacer member 51 applies a load from the optical writing head 103 to the photoconductor 108 by an urging means such as a coil spring. It is configured to receive.

Here, assuming that the maximum exposure width on the photoconductor 108 is L1, in order to suppress wear of the photoconductor 108 within the maximum exposure width L1, the spacer member 51 in contact with the photoconductor 108 is outside the maximum exposure width L1. Has been placed.

In the present embodiment, each spacer member 51 is in contact with the photosensitive member 108 at two locations separated from each other in the axial direction. That is, as shown in FIG. 5A, each spacer member 51 has a linear portion 51b and an inclined portion 51c that contact the photoconductor 108 at positions separated from each other.

These are arranged one by one on both sides of the photosensitive member 108 so as to avoid the boundary (cleaning region end) of the photosensitive member cleaning blade width L4 with which the cleaning blade 209 contacts. This is because streaky sticking foreign matter is generated in the vicinity of the boundary.

That is, by arranging linear portions 51b and inclined portions 51c (to be described later) of the spacer member 51 on both sides of the boundary of the photosensitive member cleaning blade width L4, streak-like fixed foreign matter is formed between the photosensitive member 108 and the spacer member 51 ( The contact surface is prevented from entering. This prevents a decrease in the positional accuracy of the optical writing head 103 with respect to the photosensitive member 108 due to the entry of a fixed foreign substance between the photosensitive member 108 and the spacer member 51.

A foreign matter removing member 71 described later is disposed on the downstream side of the spacer member 51 close to the driven gear 1082. The foreign matter removing member 71 may be arranged on the downstream side of the opposite spacer member 51 as shown by a chain line in FIG.

5A (a) to 5 (c) are two perspective views showing the spacer member 51 and a bottom view thereof. The spacer member 51 includes a trapezoidal plate-like portion 51a serving as a base, and two rib-like leg portions provided on the photosensitive member 108 side of the plate-like portion 51a (lower sides of FIGS. 5A (a) and 5 (b)). Have

One rib-like leg portion is a straight portion 51 b extending in the circumferential direction of the photoconductor 108. The other leg portion is an inclined portion 51 c that forms an inner end portion that is inclined with respect to the axial direction of the photoconductor 108 and faces each other. The straight portion 51b and the inclined portion 51c are spaced apart from each other by parallel to the plate-like portion 51a at a right angle to the plate-like portion 51a and at a predetermined interval in the axial direction of the photoconductor 108. Is formed.

As shown in FIG. 4, the spacer members 51 are arranged in a pair of left and right at both ends in the axial direction of the photosensitive member 108. Although the spacer member 51 is symmetrical, the number of the columnar parts 51d integrally formed on the upper side of the plate-like part 51a is different.

The number of the columnar portions 51d is one in the left spacer member 51 and two in the right spacer member 51 in FIG. The number may be reversed left and right. Each of the columnar parts 51d is arranged at a position close to the center of the columnar part 51d. The reason why the columnar part 51d is arranged at such a position will be described later with reference to FIGS. 6, 7A and 7B.

5A (a) to 5 (c) illustrate the right spacer member 51. Two prismatic columnar portions 51d are integrally formed on the upper side of the plate-shaped portion 51a. A total of three columnar portions 51d on the left and right sides are formed with the same shape and height, and the upper end surface of the columnar portion 51d is formed in parallel with the lower surface (contact reference surface) of the optical writing head 103. Then, the upper end surfaces of the three columnar portions 51d are in contact with the lower surface of the optical writing head 103, so that the posture and height of the optical writing head 103 with respect to the surface of the photosensitive member 108 are uniquely determined by so-called three points. It has come to be determined. In addition, the columnar part 51d does not need to be prismatic, and may be cylindrical as shown in FIGS. 5B (a) to 5 (c).

The inclined portion 51c and the linear portion 51b are in sliding contact with the surface of the photoconductor 108 in a state where the spacer member 51 is disposed between the optical writing head 103 and the photoconductor 108. As shown in FIGS. 5A (a) and 5 (b), the contact surface between the inclined portion 51c and the linear portion 51b is formed in an arc shape following the surface shape of the photosensitive member 108, whereby the inclined portion 51c and the linear part 51b are in sliding contact with the photoreceptor 108 in a stable posture.

The inclined portion 51c and the straight portion 51b are formed in a rib shape extending along the surface of the photoreceptor 108. For this reason, the inclined portion 51 c and the straight portion 51 b are easily elastically deformed along the surface of the photoconductor 108, and a gap is less likely to be generated between the photoconductor 108.

In particular, since the inclined portion 51c is narrower than the straight portion 51b, the inclined portion 51c is more likely to be elastically deformed and more easily contacted with the photoreceptor 108. In addition, as shown in FIG. 5A (c), the tip width t1 of the inclined portion 51c is formed to be smaller than the root width t2. For this reason, the tip width t1 and the root width t2 are more easily elastically deformed than the same.

As described above, the inclined portion 51c is particularly easily elastically deformed, so that it is difficult for a gap to be formed between the inclined portion 51c and the photosensitive member 108. Accordingly, the cleaning residue hardly passes between the contact surfaces of the inclined portion 51c and the photosensitive member 108, and moves along the inclination of the inclined portion 51c. Therefore, the cleaning residue adheres within the maximum exposure width L1. Can be suppressed.

FIGS. 6A and 6B show a state in which streaky fixed foreign matters are formed. Foreign matter such as residual toner in the vicinity of the axial end of the toner thin layer region on the photoconductor 108 comes into contact with the inclined portion 51c of the spacer member 51 by the rotation of the photoconductor 108, and is guided by the inclined portion 51c to be photosensitive. The body 108 is moved outward in the axial direction. However, the foreign matter colliding with the upstream end of the inclined portion 51c (the end of the spacer member 51) does not move outward in the axial direction of the photosensitive member 108, but falls from the upstream end of the inclined portion 51c inward in the axial direction. The surface of the body 108 may be fixed as a circumferential streak. The streak-like image is formed by transferring the streak-like fixing to the end in the width direction of the paper. In the present embodiment, such streaky fixed foreign matter is removed by the foreign matter removing member 71 of the foreign matter removing mechanism described below.

(Foreign matter removal mechanism of photoconductor)
Next, the foreign matter removing mechanism of the photoconductor 108 will be described. As shown in FIGS. 3A and 3B, this foreign matter removing mechanism has a rectangular plate-like foreign matter removing member 71 urged toward the surface of the photoreceptor 108 by a spring 72a.

The foreign matter removing member 71 is disposed on the downstream side in the circumferential direction of the photosensitive member 108 as seen from the spacer member 51 as shown in FIG. 3A, or the photosensitive member 108 as seen from the spacer member 51 as shown in FIG. It can arrange | position to the circumferential direction upstream. As shown in FIG. 3A, the arrangement of the photosensitive member 108 on the downstream side in the circumferential direction can immediately remove the sticking foreign matter generated from the edge of the spacer member 51. Therefore, the photosensitive member 108 is more sensitive than the arrangement on the upstream side in the circumferential direction. The effect of removing foreign matters adhered to the surface of the body 108 can be enhanced.

The foreign matter removing member 71 is a member that scrapes off the foreign matter that is slidably brought into contact with the surface of the photoreceptor 108 and scrapes it off by a polishing action, and can contain various inorganic fine particles having a polishing action such as cerium oxide. Specific examples of the inorganic fine particles include, besides the cerium oxide, for example, alumina, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, silica ash Examples thereof include stone, diatomaceous earth, chromium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. These can also be used as external additives for assisting the toner in fluidity, developability and chargeability.

The foreign matter removing member 71 can be formed into a rectangular plate shape by the following method, for example. That is, first, a slurry is prepared by dispersing the inorganic fine particles and a resin such as polyurethane resin in a predetermined solvent. As the solvent, for example, ketones such as methyl isobutyl ketone, methyl ethyl ketone and acetone, aromatics such as toluene, esters such as ethyl acetate, and ethers such as tetrahydrofuran can be used.

When the slurry is prepared, it is applied in a suitable rectangular mold so as to have a desired thickness. Thereafter, when the slurry is heated and dried to remove the solvent, a rectangular plate-like foreign matter removing member 71 having a polishing function on the surface can be obtained.

The foreign matter can be removed by sliding the foreign matter removing member 71 against the surface of the photoconductor 108, but it is inevitable that the surface of the photoconductor 108 is worn to some extent over time. The abrasion powder is mixed with residual toner or the like to form the above-mentioned fixed foreign matter, but is finally removed by the foreign matter removing member 71.

FIG. 7A shows the positional relationship in the axial direction between the inclined portion 51 c of the spacer member 51 and the foreign matter removing member 71 of the photoconductor 108. As shown in the figure, the foreign matter removing member 71 is disposed so that the circumferentially extending line B1 of the outer edge in the axial direction of the foreign matter removing member 71 crosses the inner front end portion of the inclined portion 51c of the spacer member 51. By arranging in this way, the fixed foreign matter T on the photoconductor generated from the end of the spacer member 51 of the optical writing head 103 (the inner front end of the inclined portion 51c) near the end of the toner thin layer region L3 becomes a foreign matter. It can be removed by the removing member 71.

On the other hand, when the foreign matter removing member 71 comes into contact with the surface of the photoconductor 108, the surface of the photoconductor 108 is worn by friction with the foreign matter removing member 71. FIG. 7A shows a state where the surface of the photoconductor 108 is worn in a circumferential belt shape.

When the entire inclined portion 51c is located at the worn portion 1083, the spacer member 51 is inclined with the straight portion 51b as a fulcrum. As a result, the distance between the optical writing head 103 and the photoconductor 108 decreases, and the exposure performance deteriorates.

Therefore, in the embodiment of the present invention, only a limited portion on the tip side of the inclined portion 51c is brought into contact with the wear portion 1083. By arranging the spacer member 51 and the foreign matter removing member 71 as described above, the spacer member 51 is not inclined even when the tip side of the inclined portion 51c is placed on the wear portion 1083, and the optical writing head 103 and It is possible to prevent the distance from the photoconductor 108 from changing, and the exposure performance of the optical writing head 103 can be maintained.

In this case, as shown in FIG. 7A, the position of the columnar portion 51d that supports the load of the optical writing head 103 connects the end portion (end portion of the hatched portion) riding on the wear portion 1083 and the end portion of the linear portion 51b. The downstream side of the straight line B2. In other words, the region surrounded by the straight portion 51b, the straight line B2, and the inclined portion 51c that does not ride on the wear portion 1083 (the region marked with light ink) has a force acting on the columnar portion 51d without the spacer member 51 being inclined. It is the range to support.

When the columnar part 51d is arranged outside the thin ink region in FIG. 7A, the spacer member 51 is inclined by the load applied to the columnar part 51d, and the height position of the optical writing head 103 with respect to the photoconductor 108 is changed. Exposure performance deteriorates. 7B, when the entire inclined portion 51c is placed on the worn portion 1083, the spacer member 51 is inclined with time regardless of the position of the columnar portion 51d. As a result, the height of the optical writing head 103 with respect to the photosensitive member 108 changes, and the exposure performance of the optical writing head 103 deteriorates.

Next, with reference to FIGS. 8A and 8B, the relationship with the maximum sheet width L2 that can be passed in the arrangement of FIG. 7A described above will be described. FIG. 8A shows an example in which the foreign matter removing member 71 is disposed within the range of the photosensitive member cleaning blade width L4 and outside the maximum sheet width L2 through which paper can be passed.

By disposing the foreign matter removing member 71 at the position, even if foreign matter spills occur at the tip of the inclined portion 51c, the foreign matter can be removed by the foreign matter removing member 71. It is possible to prevent image defects adhering to the surface.

On the other hand, FIG. 8B is an example in which the foreign matter removing member 71 is arranged so as to overlap the outer position of the maximum sheet width L2 within the range of the photosensitive member cleaning blade width L4 and capable of passing paper. By disposing the foreign substance removing member 71 at the position, when a streak-like image is generated due to wear failure at the end of the life, the user can quickly execute a predetermined cleaning maintenance or know the end of the life of the process unit 102. it can. That is, when foreign matter spills at the tip of the inclined portion 51c, the foreign matter adheres to the margin of the paper P as a streak-like image st, so that the user can know the occurrence of fixed foreign matter on the photoconductor 108. It is.

Since the streak-shaped image st appears only in the margin, the formed image im is not disturbed. In general, the life of the process unit 102 is notified to the user from the counter information of the main body of the image forming apparatus 100 or the chip information of the process unit 102. However, the user is alerted only by the output image of the paper P. By issuing a (warning), you can be sure of the end of your life.

(Foreign matter removal member mounting structure)
9A and 9B show an example of the attachment structure of the foreign matter removing member 71. FIG. 9A is a perspective view of one end portion of the photoconductor 108, and FIG. 9B is a cross-sectional view of the same portion. As described above, the foreign matter removing member 71 is composed of a member having a polishing performance for removing the sticking foreign matter on the photoreceptor 108.

The foreign matter removing member 71 is connected to a holder 80 that holds the spacer member 51 via a support plate 72. Thus, by holding the foreign substance removing member 71 with the same holder 80 as the spacer member 51, the relative positioning accuracy between the spacer member 51 and the foreign substance removing member 71 can be improved.

The support plate 72 that holds the foreign matter removing member 71 is preferably made of a leaf spring material having spring properties such as SUS301. This eliminates the need for the spring 72a shown in FIGS. 3A and 3B as a separate component, and can reduce the number of components.

The foreign matter removing member 71 can be easily fixed to the tip of the support plate 72 with a double-sided tape or an adhesive. Using the deflection of the support plate 72, the foreign matter removing member 71 can be stably urged toward the photoconductor 108 by a simple and low-cost method.

The foreign matter removing member 71 is brought into contact with the rotating direction of the photoconductor 108 in the trading direction. As a result, the fine powder scraped off by the foreign matter removing member 71 on the photoconductor 108 steadily flows downstream, so that it is possible to prevent the sticking foreign matter from being generated from the foreign matter removing member 71. The fine powder that has been scraped off and has flowed downstream on the surface of the photoconductor 108 is again scraped off by the photoconductor cleaning blade 209, and is transported to the waste toner container 124 together with the waste toner and collected.

(Modified Embodiment of Foreign Object Removal Mechanism)
FIG. 10 shows a modified embodiment of the foreign matter removing mechanism used in the process unit 102 of FIG. In this modified embodiment, the foreign matter removing member 711 is not located at the position shown in FIG. 3A or 3B (both are downstream of the charging roller 110), but upstream of the charging roller 110, that is, the rotation of the photoconductor 108. It is disposed upstream of the charging roller 110 as viewed from the direction and downstream of the cleaning blade 209. This foreign matter removing member 711 is supported by the holder 81 of the cleaning blade 209.

In the embodiment described above, the foreign matter removing member 71 is connected to the holder 80 that holds the spacer member 51 via the support plate 72 as shown in FIGS. 9A and 9B. However, in this configuration, the foreign matter removing member 71 is optically written. Supported by the casing of the head 103. Since the housing of the optical writing head 103 is generally made of resin, it is difficult to ensure sufficient rigidity of the holder 80. On the other hand, the holder 81 of the cleaning blade 209 is usually made of metal, and by attaching the foreign matter removing member 711 to the holder 81, the support rigidity of the foreign matter removing member 711 can be increased, and the foreign matter removing member 711 can be used as a photoreceptor. 108 can be pressed against the surface with sufficient and stable force.

The shape and the axial direction position of the foreign substance removing member 711 may be exactly the same as those in the above-described embodiment (see FIG. 4), and are shifted slightly outside the maximum sheet width L2 through which paper can be passed as shown in FIG. 11A. Also good. As a result, while the photoconductor 108 in the image area is prevented from being worn, foreign matter fixed on the photoconductor at the end of the toner thin layer can be scraped off, and it grows from minute scratches on the photoconductor due to the edge of the spacer member 51. It is also possible to scrape off foreign matter adhering to the photoreceptor.

Further, by disposing the foreign matter removing member 711 on the upstream side of the charging roller 110, it is possible to eliminate the influence on the electrostatic latent image, that is, the influence of the foreign matter removing member 711 on the surface of the photoconductor in the image area. The arrangement position of the foreign substance removing member 711 in the axial direction of the photoconductor 108 can be set in a wider range than the embodiment of FIG. Therefore, as shown in FIG. 11B, the inner edge of the foreign substance removing member 711 can be disposed so as to extend inside the maximum sheet width L2 through which paper can be passed and inside the maximum exposure width L1.

The foreign matter removing member 711 can be used in an image forming apparatus using the LED type optical writing head 103 as in the embodiment described above as shown in FIG. 11A. The foreign matter removing member 711 is an image forming apparatus that does not use the LED type optical writing head 103 as shown in FIG. 11C, for example, an optical scanning apparatus that performs optical writing by scanning the surface of the photoreceptor 108 with laser light in the axial direction. It can also be used for an image forming apparatus having the same.

In the image forming apparatus having the optical scanning device, there is no spacer member 51 and no streaky toner generated from the edge of the spacer member 51, but streaky toner may be generated near the end of the maximum paper width. It is necessary to dispose the foreign matter removing member 711. The shape and position of the foreign substance removing member 711 may be the same as in FIG. 11A.

The foreign matter removing member 711 in FIGS. 11A to 11C has a simple rectangular shape. However, the foreign matter removing member 711 has an elongated rectangular or strip shape like the foreign matter removing member 712 in FIGS. 12A and 12B, and is inclined with respect to the axial direction of the photoconductor 108. May be arranged. By adopting such a shape and arrangement of the foreign matter removing member 712, foreign matters such as residual toner on the photoconductor 108 are moved outward in the axial direction of the photoconductor 108, thereby preventing streaky toner from being transferred to the paper. can do. Further, by adopting such an inclined arrangement, the foreign matter removing member having the same width in the longitudinal direction of the photoconductor 108 is more sensitive than the one arranged in parallel to the axis of the photoconductor 108. Since the contact area with the body 108 increases, the removal performance can be improved.

FIG. 13 shows a structure for attaching the foreign matter removing member 711 of FIGS. 10 to 11C to the cleaning blade holder 81. The cleaning blade 209 is disposed on the upstream side of the charging roller 110 shown in FIG. 2, and extends in the axial direction of the photosensitive member 108 as indicated by a width L4 in FIG. The cleaning blade holder 81 has substantially the same width L4 as the cleaning blade 209, and is fixed to the process unit case 1021 as shown in FIG.

That is, on the inner surface of the process unit case 1021, a pair of left and right projections 1021a for positioning both ends of the cleaning blade holder 81 are integrally formed. The convex portion 1021 a has a cylindrical shape with a tapered tip, and the cleaning blade holder 81 is positioned in the process unit case 1021 by inserting the convex portion 1021 a into the holes 81 e at both ends of the cleaning blade holder 81. Is done.

The cleaning blade holder 81 is made of a metal plate and has an L-shaped cross section for imparting rigidity, and a pair of left and right positioning holes 81e are formed on the surface of the long side portion 81b of the L-shaped cross section. Has been. And the front-end | tip of the convex part 1021a protrudes from the hole 81e by predetermined length.

The foreign substance removing member 711 is formed in a rectangular plate shape as shown in FIG. 13, and the upper end side is formed in the thick part 711a, and the thick part 711a is formed with a hole 711c through which the convex part 1021a can pass. Yes. With the convex portion 1021a inserted into the hole 711c, the upper edge of the foreign material removing member 711 comes into contact with the short side portion 81a of the cleaning blade holder 81 so that the position of the foreign material removing member 711 is accurately determined. .

By positioning the foreign substance removing member 711 in this manner, it is not necessary to add a new positioning member or to add an existing part, and the foreign substance removing member 711 can be installed at a low cost. Further, the foreign substance removing member 711 is more stably installed on the metal cleaning blade holder 81 than the case where the foreign substance removing member 711 is installed on the resin holder 80 as shown in FIGS. 9A and 9B. 108 abuts.

The lower side of the thick part 711a of the foreign matter removing member 711 is formed in a thin part 711b having a thickness about half that of the thick part 711a. The cleaning blade 209 is sandwiched between the thin portion 711b and the cleaning blade holder 81, and the upper end portion of the cleaning blade 209 is in contact with the step portion between the thick portion 711a and the thin portion 711b. The cleaning blade holder 81, the cleaning blade 209, and the foreign matter removing member 711 are fixed to each other with a double-sided tape or an adhesive.

14A and 14B show a modified embodiment in which the foreign matter removing member 713 is movably arranged in the vertical direction. In other words, in this modified embodiment, the foreign matter removing member 713 is urged downward by the spring 84, that is, toward the photoreceptor 108 side. As shown in FIGS. 14B and 15A, the foreign matter removing member 713 includes an upper urethane rubber layer 713a and a lower abrasive layer 713b. The upper surface of the urethane rubber layer 713a is a double-sided tape on the lower surface 83a of the resin holding member 83. Alternatively, it is fixed by an adhesive or the like. The holding member 83 is biased toward the photoconductor 108 by a pair of left and right springs 84. Further, both ends of the cleaning blade 209 are disposed between the holding member 83 and the cleaning blade holder 81.

In the vicinity of both ends of the cleaning blade holder 81, vertically long rectangular holes 81c for attaching the springs 84 are formed in two parallel rows. A coiled spring 84 is accommodated in each rectangular hole 81c. The upper end portion of the spring 84 is held by a convex portion formed on the inner edge of the rectangular hole 81 c, while the lower end portion of the spring 84 is held by a pair of left and right convex portions 83 d formed on the holding member 83.

The upper end portion 83 b of the holding member 83 is formed in a rectangular plate shape, and the upper end portion 83 b is attached to the cleaning blade holder 81 so as to be movable up and down. That is, a longitudinal slot 83c is formed at the center of the upper end 83b, and the projection 1021a protruding from the hole 81e of the cleaning blade holder 81 is inserted into the slot 83c. L-shaped engaging portions 83e are formed at both ends of the holding member 83, and the engaging portions 83e are engaged with the lower edge of the rectangular hole 81c.

The abrasive layer 713b contains inorganic fine particles having an abrasive action such as cerium oxide, and is in contact with the photosensitive member 108 rotating in the clockwise direction as shown in FIG. 14B in the trading direction. As a result, the fine powder scraped off by the abrasive layer 713b of the foreign matter removing member 713 on the photoconductor 108 constantly flows downstream, thereby preventing the sticking foreign matter from being generated in the form of streaks from the foreign matter removing member 713. be able to. The fine powder that has been scraped off and has flowed downstream on the surface of the photoconductor 108 is again scraped off by the photoconductor cleaning blade 209, and is transported to the waste toner container 124 together with the waste toner and collected.

(Support structure for foreign matter removal mechanism by leaf spring)
Next, a modified example of the structure in which the foreign matter removing member 71 is supported on the cleaning blade holder 81 by the leaf spring 72 will be described with reference to FIGS. In the modification of FIG. 16, the foreign matter removing member 71 is attached to the cleaning blade holder 81 by a flat plate spring 72. As the leaf spring 72, a spring having a spring property such as SUS301 is used. Accordingly, the foreign matter removing member 71 can be stably biased to the photosensitive member 108 by a simple method using the deflection of the leaf spring 72.

The foreign matter removing member 71 is disposed downstream of the cleaning blade 209 and upstream of the charging roller 110 described above. The foreign matter removing member 71 abuts the photosensitive member 108 rotating in the clockwise direction in the trading direction, thereby preventing the sticking foreign matter from being generated in the form of streaks from the foreign matter removing member 71 as described above. it can. The fine powder that has been scraped off and has flowed downstream on the surface of the photoconductor 108 is again scraped off by the photoconductor cleaning blade 209, and is transported to the waste toner container 124 together with the waste toner and collected.

In addition to a flat plate shape as shown in FIG. 16, the leaf spring 72 can be used in a bent shape bent at at least one place as shown in FIG. When the leaf spring 72 extends from the substantially same direction as the cleaning blade 209 toward the photosensitive member 108, the trailing contact can be realized by adopting such a bent shape.

By bending the leaf spring 72, the elasticity of the bent tip 72c is enhanced, and the ability of the foreign matter removing member 71 to remove streaky fixed foreign matter on the photoconductor 108 is enhanced. When the leaf spring 72 is attached to the cleaning blade holder 81, a configuration in which bending is further added to avoid the rubber portion on the proximal end side of the cleaning blade 209 may be employed.

That is, in the example of FIG. 17, the leaf spring 72 is bent at three locations until reaching the bent tip 72 c. The rising portion 72a is formed by the first bending, and the rising portion 72a overcomes the thickness of the rubber on the proximal end side of the cleaning blade 209. A portion 72b that covers the proximal end side of the cleaning blade 209 by the second bending is formed. The third is an acute angle bent portion 72j.

The bent tip portion 72c is formed first from the bent portion 72j, and the foreign matter removing member 71 is fixed to the bent tip portion 72c with an adhesive or a double-sided tape. Since the bent tip 72c can swing about the bent portion 72j, the ability to remove streaky fixed foreign matter by the foreign matter removing member 71 is enhanced as described above.

FIG. 18 shows a specific mounting structure of the leaf spring 72 to the cleaning blade holder 81 in the process unit 102. The plate spring 72 is bent as shown in FIG. 17 described above, and a bent tip 72 c facing the outer peripheral surface of the photoreceptor 108 is formed at the tip of the plate spring 72. The bent tip 72c is formed on the tip side of the third bent portion 72j, and can swing in the radial direction of the photoconductor 108 with the bent portion 72j as a center.

The base end side of the leaf spring 72 is clamped together with the cover member 73 and the cleaning blade holder 81 together with the cover member 73 while being sandwiched between the cleaning blade holder 81 and the cover member 73. The cover member 73 can be made of any material such as metal, ceramic, or resin as long as it has a predetermined strength and durability. However, the cover member 73 can be made of a metal and can save space.

When the cover member 73 is not present, repeated vibrations occur in which the foreign matter removing member 71 slightly moves in the rotational direction of the photosensitive member 108 due to the sliding load of the foreign matter removing member 71 and the photosensitive member 108 and returns to the original position. To do. As a result, abnormal sounds such as chattering and squealing may be generated. By providing the cover member 73, the vibration of the leaf spring 72 can be suppressed and the occurrence of abnormal noise can be suppressed.

As the urging means of the foreign matter removing member 71, the leaf spring 72 is made of a spring material such as SUS, so that the fixing force can be kept within a range where the urging force of the leaf spring 72 is not lost. That is, in the case of the configuration shown in FIG. 19, it is preferable that the bent portion 72j and the subsequent portions be free (cantilevered).

FIG. 19 schematically shows the procedure for assembling the leaf spring 72. First, the leaf spring 72 is positioned on the cleaning blade holder 81 as shown in FIG. Then, a cover member 73 is put on the base end portion of the leaf spring 72 as shown in FIG. Then, it is fixed with the screw 74 described above.

FIG. 20 shows a state in which the leaf spring 72 is assembled in the process unit 102. FIG. 21 shows a structure for attaching the leaf spring 72 to the process unit 102. Here, when the charger 110 is arranged close to the downstream side of the cleaning blade 209 as shown in FIG. 20, it is necessary to pay attention to the discharge of the leaf spring 72.

That is, it is preferable to provide a gap of 1 mm or more between the cover member 73 and the charger 110 so that the leaf spring 72 that supports the foreign matter removing member 71 does not discharge between the cover member 73. However, when an insulating resin material is used for the cover member 73, it is difficult for the discharge to occur. Therefore, a layout in which the gap is 1 mm or less is also possible.

As shown in FIG. 21D, the cleaning blade holder 81 is formed with two half-cut convex holes 81d, one through hole 81g, and two screw holes 81f. The half punched convex hole 81d protrudes to the near side in FIG.

On the other hand, on the attachment surface of the leaf spring 72 facing the two convex holes 81d, as shown in FIG. 21 (c), two half-cut convex holes 72e, one through hole 72f, and two through holes 72g are formed. Has been. The half punching convex hole 72e protrudes to the near side.

By positioning and fitting the convex hole 81 d of the cleaning blade holder 81 into the convex hole 72 e of the plate spring 72, the plate spring 72 can be easily positioned with respect to the cleaning blade holder 81. In FIG. 21, the boss 1021a on the outer case 1021 side for positioning the cleaning blade holder 81 with respect to the outer case 1021 of the process unit 102 using the through hole 81g is positioned, for example. If used, the half punch boss can be provided at one place (for rotation prevention).

After positioning the leaf spring 72 in this way, the cover member 73 is put on the proximal end side of the leaf spring 72. The cover member 73 has a pressing portion 73 a that holds and fixes the proximal end side of the cleaning blade 209. Further, the cover member 73 has two through holes 73b for receiving the convex holes 72e of the leaf spring 72 and a rectangular long hole 73c for preventing the boss 1021a on the exterior case 1021 side from interfering with the base end side of the pressing portion 73a. And a through hole for the screw 74 located on both sides of the elongated hole 73c.

Two screws 74 are used for fastening the cover member 73. By providing the screw hole 81 f in the cleaning blade holder 81 in advance, the leaf spring 72 and the cover member 73 can be easily fastened to the cleaning blade holder 81.

The plate thickness of the plate spring 72 is preferably set to 1.0 mm or more in order to secure the amount of the screw 74. When the plate thickness is moderately large, the height of the positioning half-extruded convex hole 72e can be increased, so that the setability when the cover member 73 is assembled can be improved.

The characteristics of the above modified examples are summarized as in the following Invention 11-18.
[Invention 11]
9. The foreign matter removing mechanism according to claim 8, wherein the foreign matter removing member is urged against the photoconductor by a leaf spring. According to the eleventh aspect, the removal member can be brought into contact with the photoconductor with an inexpensive and simple configuration, and space saving can be realized.
[Invention 12]
The foreign matter removing mechanism according to claim 11, wherein the leaf spring accesses the photoconductor from substantially the same direction as the cleaning blade and has at least one bent portion to hold the foreign matter removing member. An image forming apparatus. According to the twelfth aspect, the removing member can be brought into the trailing contact with an inexpensive and space-saving configuration.
[Invention 13]
13. The foreign matter removing mechanism according to claim 12, further comprising a cover member that holds the leaf spring between the cleaning blade holder. According to the thirteenth aspect, it is possible to suppress the vibration of the leaf spring due to the frictional force between the foreign matter removing member and the photosensitive member.
[Invention 14]
14. The foreign matter removing mechanism according to claim 13, wherein the cover is an insulating resin member. According to the fourteenth aspect, it is possible to suppress the occurrence of an abnormal image without discharging even when the distance to the charging roller is short.
[Invention 15]
14. The foreign matter removing mechanism according to claim 13, wherein the cover is a metallic plate material. According to the fifteenth aspect, since the cover member is metallic, the vibration of the leaf spring can be suppressed even if it is thin.
[Invention 16]
The foreign matter removing mechanism according to any one of claims 13 to 15, wherein the cover member is fastened together with a leaf spring. According to the sixteenth aspect, it is possible to fasten the leaf spring which is a holder for the cover member and the foreign matter removing member with a simple configuration.
[Invention 17]
The foreign matter removing mechanism according to a sixteenth aspect of the invention is characterized in that the cleaning blade holder has a plate thickness of 1.0 mm or more and has a screw hole into which a screw for fastening the cover member and the leaf spring is inserted. Foreign matter removal mechanism. According to the seventeenth aspect, the leaf spring that is the holder for the cover member and the foreign matter removing member can be fastened with a simple configuration.
[Invention 18]
18. A foreign matter removing mechanism according to any one of claims 13 to 17, wherein the cleaning blade holder has a half punched convex hole, and the cover member and the leaf spring are positioned together in the half punched convex hole. According to the eighteenth aspect, the holder of the cover member and the foreign matter removing member can be positioned with a simple configuration.

The embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the present invention. For example, the foreign substance removing member 71 does not have to be a rectangular plate shape, and the shape is arbitrary, and the disposition position on the photosensitive member 108 is also arranged on the upstream side or the downstream side in the circumferential direction of the photosensitive member 108 from the inner end portion of the spacer member 51. It is optional as long as it extends across the extended line.

In the above-described embodiment, the drum-shaped photoconductor 108 is exemplified. However, instead of the drum-shaped photoconductor 108, for example, an endless belt-shaped so-called photoconductor belt may be used. In this case, a spacer member is brought into contact with the stretching roller (backup roller) of the photosensitive belt via the photosensitive belt, and the optical writing head 103 is positioned with respect to the photosensitive belt by the spacer member.

101a-101d: transfer roller 102a-102d: process unit 103a-103d: optical writing head 108a-108d: photoconductor 51: spacer member 51a: plate-like part 51b: linear part 51c: inclined part 51d: columnar part 71,711 713: Foreign material removing member 72: Support plate 72a: Spring 80: Holder 81: Cleaning blade holder 82: Seal member 83: Holding member 84: Spring 100: Image forming apparatus 103: Optical writing head 1031: Light emitting element 104: Supply Paper tray 105: Paper feed roller 106: Fixing device 106a: Fixing roller 106b: Pressure roller 107: Timing roller pair 108: Photoreceptor 1081: Photosensitive member support shaft 1082: Photosensitive member driven gear 1083: Photoreceptor wear Part 110: Charger 111: Developing roller 112: Paper discharge Roller 113: Paper discharge tray 120: Intermediate transfer belt 121: Tension roller 122: Drive roller 123: Cleaning blade 124: Waste toner storage unit 125: Secondary transfer roller 126: Toner density detection means 130: Control unit 131: Development control Means 132: Temperature sensor 133: Humidity sensor 201: Toner supply container 202: Conveying means 203: Developing chamber 204: Agitator 205: Toner transport member 206: Supply roller 207: Restricting blade 208: Stir paddle 209: Cleaning blade 210: Toner leakage Prevention sheet 211: Residual amount detection sensor 212: Development bias application unit 213: Supply bias application unit 214: Toner transport member B1: Circumferential extension line L1: Maximum exposure width L2: Maximum sheet width L3: Toner thin layer region L4: Photoreceptor Cree Ring Blade Width P: sheet st: streaky image T: on the photoreceptor fixed foreign matter t1: End width t2: root width

JP2015-31708A JP2015-108645A Japanese Patent Laid-Open No. 61-120181 JP 2004-252030 A JP-A-2005-141109 JP 2004-045771 A

Claims (10)

The maximum sheet width that can be passed and the maximum exposure width inside the maximum sheet width are set on the inner side in the width direction of the toner thin layer area formed in the circumferential direction. A photoreceptor carrying an image and a toner image;
A pair of inner end portions that are disposed at both ends in the axial direction of the photoconductor and are opposed to each other through a spacer member that is slidably contacted with the surface of the photoconductor so as to bite into both ends in the width direction of the toner thin layer region. An optical writing head that is positioned on the surface of the photoreceptor and forms the electrostatic latent image by exposing the surface of the photoreceptor;
A developing member that forms a toner image by supplying a toner thin layer as a developer to the toner thin layer region on the surface of the photoreceptor after exposure;
Using an image forming apparatus having a cleaning member for removing the developer remaining on the surface of the photoreceptor,
In the foreign matter removing mechanism of the photosensitive member for removing foreign matter including toner remaining on the axial end portion on the photosensitive member after the toner image on the photosensitive member is transferred to a sheet or intermediate transfer material as a transfer material,
A foreign matter removing member that slides in contact with the surface of the photoconductor and scrapes off the foreign matter that adheres to the surface of the photoconductor from the inner end of the spacer member that bites into the widthwise end of the toner thin layer region. A foreign matter removing mechanism for a photoreceptor, which is disposed so as to cross an extended line extending upstream or downstream.   The foreign matter removing mechanism according to claim 1, wherein the foreign matter removing member is disposed on the outer side in the axial direction of the maximum paper width through which paper can pass.   2. The foreign matter removing mechanism according to claim 1, wherein the inside edge of the foreign matter removing member is disposed outside the maximum exposure width and inside the maximum paper width that allows paper to pass.   The pair of spacer members have inclined portions that constitute inner end portions that are inclined with respect to the axial direction of the photoconductor and face each other, and linear portions that extend in the circumferential direction of the photoconductor, and the foreign matter The foreign matter removing mechanism according to any one of claims 1 to 3, wherein the foreign matter removing member is arranged so that a circumferentially extending line of an outer edge in the axial direction of the removing member crosses an inner front end portion of the inclined portion. .   The foreign matter removing mechanism according to claim 1, wherein the foreign matter removing member contains cerium oxide.   6. The foreign matter removing mechanism according to claim 1, wherein the foreign matter removing member contacts the photoconductor in a trading direction.   The foreign matter removing mechanism according to claim 1, wherein the foreign matter removing member is connected to the spacer member via a support member.   The foreign matter removing mechanism according to any one of claims 1 to 6, wherein the foreign matter removing member is attached to a holder that holds the cleaning member.   A process unit comprising the foreign matter removing mechanism according to claim 1. An image forming apparatus comprising the process unit according to claim 9.