JP2018097319A - Developing unit and image forming apparatus - Google Patents

Abstract

There is provided means for suppressing variation in toner regulating force caused by a developer regulating member and suppressing deterioration in image quality formed on a recording medium. A photosensitive member on which an electrostatic latent image is formed, a developer carrying member that develops the electrostatic latent image, and a developer regulating member that is bent in contact with the developer carrying member. The developer regulating member is sandwiched between the first holding member and the second holding member and fixed with screws, and the first holding member is a fixing portion that fixes the developer regulating member with the screws. And a fulcrum part serving as a fulcrum of the developer restricting member that contacts and bends the developer restricting member, and the fixed part and the fulcrum part are divided surfaces of the first holding member. Respectively. [Selection] Figure 1

Description

  The present invention relates to a developing device and an image forming apparatus having a developing blade.

A conventional image forming apparatus uniformly and uniformly charges the surface of a photoconductor, exposes the charged surface to form an electrostatic latent image, and attaches toner to the electrostatic latent image to form a toner image. Form. The toner image formed on the surface of the photoconductor is transferred to a recording medium and then fixed to form an image on the recording medium.
Such an image forming apparatus includes a developing unit that forms toner images by conveying toner supplied from a toner cartridge to a photosensitive member by a developing roller, and extends in the direction of the rotation axis of the developing roller provided in the developing unit. A developing blade that regulates the amount of toner on the developing roller by contacting is provided (see, for example, Patent Document 1).

JP 2008-89808 A

However, in the conventional technology, when a developing blade as a developer regulating member is sandwiched between two holding members and fixed at a plurality of positions with screws, the difference in rigidity between the screw fixing portion of the developing roller and other portions is caused. , The deflection of the developing blade cannot be held uniformly in the axial direction of the developing roller, the toner restricting force on the developing roller varies, and toner density difference occurs in the toner image. There is a problem that the quality of the image formed on the medium is degraded.
An object of the present invention is to solve such a problem, and an object of the present invention is to suppress variation in toner regulating force by a developer regulating member and to suppress deterioration in image quality formed on a recording medium.

  Therefore, the present invention provides a photosensitive member on which an electrostatic latent image is formed, a developer carrying member that develops the electrostatic latent image, and a developer regulating member that is bent in contact with the developer carrying member. And the developer regulating member is sandwiched between the first holding member and the second holding member and fixed with a screw, and the first holding member fixes the developer regulating member with the screw. A fixing portion, and a fulcrum portion serving as a fulcrum of the developer regulating member that contacts and bends the developer regulating member, and the fixing portion and the fulcrum portion are separated from the first holding member. It is characterized by being arranged on each surface.

  According to the present invention as described above, it is possible to suppress the variation in the toner regulating force by the developer regulating member and to suppress the deterioration of the image quality formed on the recording medium.

Explanatory drawing which shows the structure of the image development blade in an Example. Schematic side sectional view showing the structure of the image forming apparatus in the embodiment Schematic side sectional view showing the configuration of the developing device in the embodiment External perspective view of the developing device in the embodiment Sectional view of the developing device in the embodiment Sectional drawing of developing roller and developing blade in embodiment Explanatory drawing of the 1st holder in an Example Explanatory drawing of the developing roller and the developing blade in the embodiment Explanatory drawing which shows the structure of the developing blade in a comparative example Explanatory drawing which shows the structure of the image development blade in a 1st modification. Explanatory drawing which shows the structure of the image development blade in a 2nd modification.

  Embodiments of a developing device and an image forming apparatus according to the present invention will be described below with reference to the drawings.

FIG. 2 is a schematic cross-sectional side view showing the configuration of the image forming apparatus in the embodiment.
In FIG. 2, an image forming apparatus 100 is an electrophotographic printer, for example, and forms an image with toner as a developer on a recording medium. The image forming apparatus 100 includes a paper cassette 20, a stacker 21, a paper feeding unit 22, a medium conveyance path 15, medium conveyance rollers 16 to 19, a developing device 23, and a transfer belt in a lower frame 28. A unit 24 and a fixing unit 25 are provided.

The paper feed cassette 20 stores recording media in a stacked manner.
The stacker 21 accumulates recording media on which images are formed.
The medium conveyance path 15 is disposed in a substantially S shape and is a path through which the recording medium is conveyed by the medium conveyance rollers 16 to 19. A paper feed cassette 20 is disposed at the beginning of the medium conveyance path 15, and a stacker 21 is disposed at the end of the medium conveyance path 15.

The medium conveying rollers 16 to 19 are a roller pair that is disposed in the medium conveying path 15 and rotates to pinch and convey the recording medium. The medium transport rollers 16 to 19 are arranged in the order of the medium transport rollers 16, 17, 18, and 19 from the upstream in the medium transport direction.
A detection unit 26 that detects the paper thickness of the recording medium to be conveyed is disposed between the medium conveyance roller 16 and the medium conveyance roller 17.

The paper feed unit 22 feeds the recording medium stored in the paper feed cassette 20 and sends it to the medium transport roller 16 in the medium transport path 15.
The developing device 23 is arranged in the medium conveyance path 15 between the medium conveyance roller 17 and the fixing device 25, and forms a toner image as a developer image. In this embodiment, four developing devices 23 are arranged side by side to form toner images of four colors of yellow (Y), magenta (M), cyan (C), and black (K). To do. Note that the number of the developing devices 23 may be three or less, or five or more.

The transfer belt unit 24 transports the recording medium transported by the medium transport roller 17 by attaching it to the transfer belt 11 by electrostatic effect. The transfer belt 11 is disposed so as to face each developing device 23 and is rotatably stretched around a driving roller and a driven roller.
In the transfer belt unit 24, a transfer roller 12 is arranged to face each developing device 23 via the transfer belt 11, and a toner image formed by each developing device 23 is applied by applying a transfer voltage to the transfer roller 12. 11 is transferred to the recording medium conveyed.

The fixing unit 25 is disposed downstream of the transfer belt unit 24 in the medium conveyance direction, and fixes the toner to the recording medium on which the toner image is transferred with heat and pressure.
The recording medium on which the toner image is fixed by the fixing unit 25 is discharged to the stacker 21 by the medium transport rollers 18 and 19.
FIG. 3 is a schematic cross-sectional side view showing the configuration of the developing device in the embodiment.

In FIG. 3, the developing unit 23 includes a photosensitive member 1, a charging roller 2, a light source 3, a toner cartridge 5, a developing roller 6, a developing blade 7, a toner supply roller 8, a cleaning blade 9, a frame. 10.
The photosensitive member 1 as an image carrier is a drum on which an electrostatic latent image is formed and is rotatably supported at a predetermined rotational speed. The photoreceptor 1 can store electric charges on the surface, and can remove the electric charges on the surface by exposure to form an electrostatic latent image.

The charging roller 2 as a charging unit is rotatably supported so as to come into contact with the surface of the photoreceptor 1 with a constant pressure. The charging roller 2 is provided so that a predetermined voltage can be applied to the surface of the photoreceptor 1.
A light source 3 as an exposure unit is disposed above the photosensitive member 1, and an LED (Light Emitting Diode) head that forms an electrostatic latent image on the surface of the photosensitive member 1 by irradiating the surface of the photosensitive member 1 with light. It is.

The toner cartridge 5 accommodates the toner 4 therein. The toner cartridge 5 is detachably attached to the developing device 23 main body.
The developing roller 6 as a developer carrying member develops the electrostatic latent image formed on the photoreceptor 1 and is rotatably supported so as to contact the surface of the photoreceptor 1 with a constant pressure. Is. The developing roller 6 conveys the toner 4 supplied from the toner cartridge 5 to the electrostatic latent image formed on the photoreceptor 1 and develops it to form a toner image.

The developing blade 7 as the developer regulating member is bent in contact with the developing roller 6 and regulates the toner supplied from the developing roller 6 to a predetermined thickness.
The toner supply roller 8 as the developer supply means is rotatably supported so as to come into contact with the surface of the development roller 6 with a constant pressure. The toner supply roller 8 supplies the toner 4 supplied from the toner cartridge 5 to the developing roller 6.

The cleaning blade 9 is arranged so that the edge thereof is in contact with the surface of the photoreceptor 1 with a constant pressure, and scrapes off the toner remaining on the surface of the photoreceptor 1 and is made of an elastic body. .
The frame 10 constitutes an outer frame of the developing device 23 and supports the above-described members.

  A transfer roller 12 is disposed below the photoconductor 1 of the developing unit 23 so as to face the photoconductor 1 through the transfer belt 11. A voltage is applied to the transfer belt 11 and the transfer roller 12 from a high voltage power source, and the toner image formed on the surface of the photoreceptor 1 is transferred onto the recording medium 13 that is conveyed in the medium conveyance direction indicated by an arrow C in the drawing. 14 is transferred.

  4 is an external perspective view of the developing device in the embodiment, FIG. 5 is a sectional view of the developing device in the embodiment, and FIG. 6 is a sectional view of the developing roller and the developing blade in the embodiment. 4A is a perspective view seen from the upstream side in the medium conveyance direction indicated by the arrow Y in the drawing, and FIG. 4B is a perspective view seen from the downstream side in the medium conveyance direction indicated by the arrow Y in the drawing. is there.

The developing roller 6 and the developing blade 7 shown in FIGS. 5 and 6 are arranged to extend in the direction indicated by the arrow X in the drawing of the developing device 23 shown in FIG.
The direction indicated by the arrow X is the rotation axis direction of the developing roller 6 and is a direction substantially orthogonal to the medium conveyance direction indicated by the arrow Y.

In FIGS. 5 and 6, the toner supply roller 8 is composed of two rollers, a first toner supply roller 8a and a second toner supply roller 8b. The toner supply roller 8 may be constituted by a single roller.
FIG. 1 is an explanatory view showing a configuration of a developing blade in the embodiment, FIG. 1A is a perspective view of the developing blade, FIG. 1B is a cross-sectional view taken along line AA in FIG. c) is a cross-sectional view taken along arrow BB in FIG.

7 is an explanatory view of the first holder in the embodiment, FIG. 7 (a) is a perspective view of the first holder as seen from the fixed portion side, and FIG. 7 (b) is as seen from the arm portion side. FIG. 7C is a cross-sectional view taken along the CC arrow in FIG. 7B, and FIG. 7D is a cross-sectional view taken along the DD arrow in FIG. 7B.
1 and 7 indicate the direction of the rotation axis of the developing roller, and arrow Y indicates the direction orthogonal to the direction of the rotation axis of the developing roller.

In FIGS. 1, 6 and 7, the developing blade 7 is sandwiched between a first holder 30 as a first holding member and a second holder 31 as a second holding member. Is held and fixed by screws 32 at a plurality of screw fixing portions 37 in the rotation axis direction of the developing roller.
The first holder 30 is composed of a single member, and has a fixed portion 33, an arm portion 34, and a fulcrum portion 35.

The fixing part 33 fixes the developing blade 7 sandwiched between the second holder 31. The fixing portion 33 has a fixing surface 33 a that is fixed to the second holder 31 with a screw 32, and is fixed to the surface of the second holder 31 via the developing blade 7.
The arm portion 34 is formed between the fixed portion 33 and the fulcrum portion 35, and a fulcrum portion 35 that is in contact with the surface of the second holder 31 via the developing blade 7 is formed at the tip portion. The arm portion 34 presses the developing blade 7 against the second holder 31 at a fulcrum portion 35 formed at the tip portion continuous from the fixing portion 33.

The fulcrum portion 35 is a portion that is a fulcrum of the developing blade 7 that contacts and bends the developing blade 7. The fulcrum portion 35 has a fulcrum surface 35a that contacts the developing blade 7 and a fulcrum 35b that becomes a fulcrum when the developing blade 7 is bent at the end of the fulcrum surface 35a.
Further, the arm portion 34 is formed with at least one bent portion 40a, 40b, 40c as a bent portion between the fixed portion 33 and the fulcrum portion 35.

The bent portions 40a, 40b, and 40c are provided at three locations between the fixed portion 33 and the fulcrum portion 35, and are formed as three bent portions that bend in the same direction at a substantially right angle, and have a substantially rectangular cross-sectional shape. Has been.
In the present embodiment, the bent portion is described as three bent portions 40a, 40b, and 40c, but may be three bent portions that are bent in the same direction. In addition, it is only necessary that at least one curved portion is formed between the fixed portion 33 and the fulcrum portion 35.

The second holder 31 supports and fixes the developing blade 7 and the first holder 30.
The second holder 31 and the fixing portion 33 of the first holder 30 are fixed with screws 32 at a plurality of points in the region of the printing range in the rotation axis direction of the developing roller 6.

The screw 32 passes through the second holder 31, the first holder 30, and the developing blade 7, and the developing blade 7 is sandwiched and fixed between the second holder 31 and the first holder 30.
In this embodiment, as shown in FIG. 1A, the screws 32 are disposed at five locations inside the printing area W in the rotation axis direction of the developing roller 6 and fix the developing blade 7.

  Moreover, as shown in FIG.1 (c), the positioning part 39 is provided in the location in which the screw | thread 32 is not arrange | positioned. The positioning unit 39 adjusts and determines the positions of the second holder 31, the first holder 30, and the developing blade 7.

  The positioning portion 39 includes a recess (or hole) formed in the fixing surface 33a of the fixing portion 33 of the first holder 30 and a protrusion formed in the second holder 31 that fits into the recess. The The convex portion of the positioning portion 39 according to the present embodiment is formed by punching, passes through a hole formed in the developing blade 7, and fits with the concave portion of the fixing portion 33 of the first holder 30. The holder 31, the first holder 30, and the developing blade 7 are positioned.

The developing blade 7 is represented by SUS301 / SUS304 and is made of a thin stainless steel material having a thickness of 0.05 to 0.15 mm. The developing blade 7 is formed in a bent shape as a contact portion 7 a in which the tip end on the free end side contacts the outer peripheral surface of the developing roller 6.
The 1st holder 30 and the 2nd holder 31 are comprised with stainless steel materials, such as a plated steel plate represented by EGC-QS1, or SUS301 / SUS304.

  In the first holder 30 of this embodiment, a fulcrum portion 35 of the developing blade 7 that is bent from the fixing portion 33 fixed by the screw 32 through the bent portions 40a, 40b, and 40c is disposed. The fixed part 33 and the fulcrum part 35 along the line 31 are discontinuous. Thus, the 1st holder 30 is each arrange | positioned on the surface into which the fixed surface 33a of the fixing | fixed part 33 and the fulcrum surface 35a of the fulcrum part 35 were divided | segmented.

The operation of the above configuration will be described.
First, the operation of the image forming apparatus will be described with reference to FIG.
The recording medium accommodated in the paper feed cassette 20 is fed from the paper feed cassette 20 by the paper feed unit 22, sent to the medium transport roller 16, and transported through the medium transport path 15 by the medium transport rollers 16 to 19. The thickness of the recording medium conveyed through the medium conveyance path 15 is detected by the detection unit 26 disposed in the medium conveyance path 15.

The recording medium whose thickness is detected is transported to the transfer belt 11 of the transfer belt unit 24 by the medium transport rollers 16 and 17, and the toner image formed by the developing unit 23 in the transfer belt unit 24 is recorded by the transfer roller 24. Transferred to the medium.
The recording medium on which the toner image has been transferred is conveyed to the fixing unit 25 by the transfer belt 11, and the toner image is fixed by heat and pressure in the fixing unit 25, and conveyed to the stacker 21 by the medium conveying rollers 18 and 19.

Next, the operation of the developing device will be described with reference to FIG.
The toner 4 supplied from the toner cartridge 5 into the toner storage chamber of the developing device 23 is supplied to the developing roller 6 by the toner supply roller 8. The toner supplied to the developing roller 6 is regulated to a constant layer thickness by the developing blade 7 and is conveyed to an electrostatic latent image formed by the light source 3 on the photoreceptor 1 to develop the toner image.

The developed toner image is transferred as a toner 14 to a recording medium 13 conveyed by a transfer belt 11 by a transfer roller 12 to which a transfer voltage is applied.
Residual toner that is not transferred to the recording medium 13 and remains on the surface of the photoreceptor 1 is scraped off by the cleaning blade 9, and the scraped toner is transported to a waste toner collecting portion by a waste toner transport spiral.

The cleaned surface of the photosensitive member 1 was neutralized by light from a static eliminator in order to make the potential difference between the area where the electrostatic latent image was formed and other areas uniform, and then a charged voltage was applied. The charging roller 2 is uniformly charged.
Next, the operation of the developing blade 7 shown in FIG. 3 will be described with reference to FIGS. 1 and 6 to 9.
The developing blade 7 is sandwiched and held between the fixing surface 33 a of the fixing portion 33 of the first holder 30 and the second holder 31, and is fixed by screws 32.

  Further, as shown in FIG. 6, the developing blade 7 is attached to the developing device 23 while being held by the first holder 30 and the second holder 31, and as shown in FIG. 8, the developing blade 7 abuts substantially uniformly in the direction of the rotation axis of the developing roller 6 (the direction indicated by the arrow X in the figure).

  The developing blade 7 is in a state where the tip side is bent from the fulcrum 35 b of the fulcrum part 35 of the first holder 30 by contacting the developing roller 6. Further, the contact portion 7a of the developing blade 7 regulates the amount of toner on the developing roller 6 to be a constant amount and uniform in the direction of the rotation axis of the developing roller 6 by contacting the developing roller 6. .

  Thus, since the developing blade 7 bends at the front end side, a pressure corresponding to the contact pressure between the developing roller 6 and the developing blade 7 is applied to the fulcrum portion 35 of the first holder 30, which is very small. The fulcrum part 35 of one holder 30 is also bent.

  Further, the first holder 30, the second holder 31, and the developing blade 7 are integrated in the vicinity of the screw fixing portion 37 (the fixing portion 37 by the screw 32 shown in FIG. 1A) due to the fixation of the screw 32. , Rigidity increases. Due to the influence, the bending of the fixing surface 33a of the fixing portion 33 of the first holder 30 differs between the vicinity of the screw fixing portion 37 and other portions, and the vicinity of the screw fixing portion 37 is smaller than the other portions.

  Therefore, a minute undulation is generated in the rotation axis direction of the developing roller 6 on the fixing surface 33 a of the fixing portion 33 of the first holder 30.

  Here, as in the comparative example shown in FIG. 9, when the fixing surface 33 a of the fixing portion 33 and the fulcrum surface 35 a are fixed to the fulcrum surface 35 a with the first holder 38 that is the same continuous surface, the screw 32 is used. Due to the fixation, the amount of bending of the first holder 38 varies in the longitudinal direction of the first holder 38, that is, in the direction of the rotation axis of the developing roller (the direction indicated by the arrow X in the figure), and the amount of bending of the developing blade 7 is reduced. Variation will also occur. For this reason, the regulation force for regulating the toner on the developing roller 6 varies, and a vertical band due to the density difference of the toner is generated in the toner image of the printing result, and the image quality is deteriorated.

  In this embodiment, the fixing surface 33a of the fixing portion 33 of the first holder 30 and the fulcrum surface 35a of the fulcrum portion 35 are respectively connected to different surfaces that are not continuous via the bent portions 40 (40a, 40b, 40c). As a result of the formation, the fixing surface 33 a of the fixing portion 33 of the first holder 30 near the screw fixing portion 37, the second holder 31, and the developing blade 7 are slightly affected by the fixing of the screw 32. Although undulation occurs, the minute undulation generated on the fixing surface 33 a of the fixing portion 33 of the first holder 30 is not transmitted to the fulcrum 35 b of the fulcrum surface 35 a of the fulcrum portion 35.

  As described above, the minute undulation of the developing blade 7 generated in the vicinity of the screw fixing portion 37 is generated as a deflection to the fulcrum surface 35a of the fulcrum portion 35 of the first holder 30, but the contact portion 7a of the developing blade 7 develops. By contacting the roller 6 and being supported by the fulcrum 35b of the fulcrum portion 35 of the first holder 30, the undulation of the developing blade 7 is corrected and the undulation is suppressed.

  Therefore, the developing blade 7 can uniformly contact the surface of the developing roller 6 in the direction of the rotation axis of the developing roller 6. Further, since the developing blade 7 can be held by the first holder 30 and the second holder 31 by fastening the screw 32, the fastening force by the screw 32 can be maintained.

  Further, the positioning portion 39 that determines the positions of the developing blade 7, the first holder 30, and the second holder 31 has a convex portion formed on the second holder 31 and a concave portion that is a fixing portion of the first holder 30. 33 is formed on the fixing surface 33a of the developing member 33, and therefore, the transmission of waviness is suppressed without increasing the dimensional variation of the developing blade 7, the first holder 30, the second holder 31, and the fulcrum portion 35 of the first holder 30. be able to.

  As described above, in this embodiment, the developing blade 7 is sandwiched between the first holder 30 and the second holder 31 and fixed with the screw 32, and the first holder 30 holds the developing blade 7 with the screw 32. A screw fixing portion 37 to be fixed and a fulcrum portion 35 that is a fulcrum of the developing blade 7 that contacts and bends the developing blade 7. The screw fixing portion 37 and the fulcrum portion 35 are separated from the first holder 30. Further, by being arranged on each surface, the undulation of the developing blade 7 can be corrected, and the variation in the regulating force of the toner on the developing roller 6 by the developing blade 7 is suppressed, and the image formed on the recording medium A reduction in quality can be suppressed.

  Next, a modification of the present embodiment will be described with reference to FIGS. 10A is a perspective view of the developing blade, FIG. 10B is a cross-sectional view taken along the line AA in FIG. 10A, and FIG. 10C is a cross-sectional view taken along the line BB in FIG. 10A. is there. Moreover, FIG. 11 is sectional drawing in a screw part, and is sectional drawing similar to FIG.10 (b). In FIG. 10, the arrow X indicates the direction of the rotation axis of the developing roller, and the arrow Y indicates the direction orthogonal to the direction of the rotation axis of the developing roller.

As shown in FIG. 10, the first holder 130 of the first modified example has a fixing part 133, an arm part 134, and a fulcrum part 135.
The fixing portion 133 is a surface that is fixed to the second holder 31 with the screw 32, and is fixed to the surface of the second holder 31 via the developing blade 7.
The arm portion 134 has a fixing surface 133 a that is fixed to the second holder 31 with the screw 32, and is fixed to the surface of the second holder 31 via the developing blade 7.

The arm part 134 is formed between the fixed part 133 and the fulcrum part 135, and a fulcrum part 135 that contacts the surface of the second holder 31 via the developing blade 7 is formed at the tip part. The arm part 134 presses the developing blade 7 against the second holder 31 at a fulcrum part 135 formed at the tip part continuous from the fixing part 133.
The fulcrum part 135 has a fulcrum 135b that serves as a fulcrum when the developing blade 7 is bent as a fulcrum surface in contact with the developing blade 7.

The arm part 134 is bent as one or more bent parts between the fixed part 133 and the fulcrum part 135 in the direction indicated by the arrow Y in the figure orthogonal to the rotation axis direction of the developing roller indicated by the arrow X in the figure. Portions 140a and 140b are formed.
The bent portion formed in the arm portion 134 of this modification has two bent portions 140a that are bent at approximately 45 degrees and two bent portions 140b that are bent at approximately 90 degrees in a direction opposite to the bending direction of the bent portion 140a. The cross-sectional shape is formed in a substantially mountain shape.

As shown in FIG. 11, the first holder 230 of the second modified example has a fixing part 233, an arm part 234, and a fulcrum part 235.
The fixing portion 233 has a fixing surface 233 a that is fixed to the second holder 31 with the screw 32, and is fixed to the surface of the second holder 31 via the developing blade 7.

  The arm part 234 is formed between the fixed part 233 and the fulcrum part 235, and a fulcrum part 235 that contacts the surface of the second holder 31 via the developing blade 7 is formed at the tip part. The arm portion 234 presses the developing blade 7 against the second holder 31 with a fulcrum portion 235 formed at the tip portion continuous from the fixing portion 233.

The fulcrum part 235 has a fulcrum surface 235a that contacts the developing blade 7, and a fulcrum 235b that becomes a fulcrum when the developing blade 7 is bent at the end of the fulcrum surface 235a.
In the arm portion 234, one or more bent portions 240a are formed between the fixed portion 233 and the fulcrum portion 235 in a direction orthogonal to the rotation axis direction of the developing roller.

In the bent portion formed in the arm portion 234 of this modification, a bent portion 240a that is bent at approximately 90 degrees is formed as one bent portion, and the cross-sectional shape is formed in a substantially semicircular shape.
The bent portion 240a may be a curved portion.
Even in the above-described two modified examples, the undulation of the developing blade 7 can be corrected, the variation in the regulating force of the toner on the developing roller 6 by the developing blade 7 is suppressed, and the image quality formed on the recording medium is reduced. Can be suppressed.

As described above, in this embodiment, the undulation of the developing blade can be corrected, the variation in the regulating force of the toner on the developing roller by the developing blade is suppressed, and the quality of the image formed on the recording medium is reduced. The effect that it can suppress is acquired.
Further, it is possible to obtain an effect that the transmission of waviness can be suppressed without increasing the dimensional variation of the developing blade, the first holder, the second holder, and the fulcrum portion of the first holder.

  In this embodiment, the image forming apparatus is described as a printer. However, the image forming apparatus is not limited thereto, and may be a copier, a facsimile machine, or a multifunction peripheral (MFP).

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Charging roller 3 Light source 5 Toner cartridge 6 Developing roller 7 Developing blade 8 Toner supply roller 9 Cleaning blade 10 Frame 15 Medium conveyance path 16, 17, 18, 19 Medium conveyance roller 20 Paper feed cassette 21 Stacker 22 Paper feeding part 23 Developing unit 24 Transfer belt unit 25 Fixing unit 30, 130, 230 First holder 31 Second holder 32 Screw 33, 133, 233 Fixing unit 33a, 133a, 233a Fixing surface 34, 134, 234 Arm unit 35, 135 235 fulcrum part 35a, 235a fulcrum surface 35b, 135b, 235b fulcrum 39 positioning part 40a, 40b, 40c, 140a, 140b, 240a bent part

Claims (8)

A photoreceptor on which an electrostatic latent image is formed;
A developer carrier for developing the electrostatic latent image;
A developer regulating member that is bent in contact with the developer carrier;
Have
The developer regulating member is sandwiched between the first holding member and the second holding member and fixed with screws.
The first holding member includes a fixing portion that fixes the developer restricting member with the screw, and a fulcrum portion that is a fulcrum portion of the developer restricting member that contacts and bends the developer restricting member.
The developing device according to claim 1, wherein the fixing portion and the fulcrum portion are respectively disposed on separate surfaces of the first holding member. The developing device according to claim 1,
A developing device, wherein at least one curved portion is formed between the fixed portion and the fulcrum portion. The developing device according to claim 2,
The developing unit, wherein the bent portions are bent portions provided at three positions between the fixed portion and the fulcrum portion, and are bent at right angles in the same direction. The developing device according to claim 2,
The developing device according to claim 1, wherein the bent portion is a bent portion provided at least one between the fixed portion and the fulcrum portion in a direction orthogonal to a rotation axis direction of the developer carrier. The developing device according to any one of claims 1 to 4,
The developing device, wherein the developer regulating member is fixed by a plurality of the screws in a printing region in a rotation axis direction of the developer carrying member. The developing device according to any one of claims 1 to 5,
The developing device according to claim 1, wherein the first holding member having the fixed portion and the fulcrum portion is formed of a single member. The developing device according to any one of claims 1 to 6,
The developing device according to claim 1, wherein the fixing surface having the fixing portion includes a positioning portion that determines a position of the developer regulating member.   An image forming apparatus comprising the developing device according to claim 1.

Images