JPH0950182A - Electrostatic latent image developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic latent image developing device capable of uniformalizing a press contact force of a blade over in the width direction, and forming toner layer formed on the surface of a developing roller in a uniform thickness over in the width direction, even if the parallelism between the developing roller and the blade composed of a rigid member varies in some degree. SOLUTION: This device is provided with a developing housing 12, the developing roller 16 placed inside the developing housing 12, a control means equipped with a blade composed of a rigid member acting on the circumferential surface of the developing roller 16 for controlling the developer quantity held on its surface. The controlling means is provided with the blade composed of the rigid member whose one-side is in press contact with the surface of the developing roller 16, the supporting member 47 consisting of a flexible member whose one end part is mounted on the blade and the other end is fixed to the developing housing 12 so as to project in almost the tangent direction on the contact point with the blade on the upstream side in rotary direction from the developing roller 16, and an elastic energizing means 48 for pressing the blade toward the contact point between it and the developing roller 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic latent image developing device used for developing an electrostatic latent image into a toner image in an image forming machine such as an electrostatic copying machine or a laser printer, and more specifically, The present invention relates to an electrostatic latent image developing device having a developing roller that holds a developer on its surface and conveys it to a developing area, and a regulating unit that regulates the amount of the developer retained on the surface of this developing roller.

[0002]

2. Description of the Related Art As is well known, in order to develop an electrostatic latent image into a toner image in an image generator, an electrostatic latent image developing device having a developing roller that is rotationally driven in a predetermined direction is widely used. Have been served. When the developing roller is driven to rotate in a predetermined direction, the developing agent holding area, the developer amount regulating area, and the developing area are sequentially moved. In the developer holding area, the developer supplied by an appropriate mode is held on the surface of the developing roller. In the developer amount regulation area, the regulation means acts on the developer retained on the surface of the developing roller to regulate the developer retained on the surface of the developing roller to a required amount. In the developing area, a developer is applied to the surface of an electrostatic latent image bearing member such as a rotating drum having an electrostatic photoconductor on the peripheral surface, and the electrostatic latent image formed on the surface of the electrostatic latent image bearing member is developed. The latent image is developed into a toner image.
In order to perform good development, the amount of developer retained on the surface of the developing roller is appropriately regulated by the regulating means, and the amount of developer retained on the surface of the developing roller is adjusted to the required amount in the width direction. It is important to make it sufficiently uniform.

Japanese Patent Publication No. 63-16736 discloses an electrostatic latent image developing device having a regulating means having a blade made of a rubber elastic body made of synthetic rubber such as urethane rubber and silicon rubber. The rubber elastic body that constitutes the developing roller has one surface or the leading edge thereof pressed against the surface of the developing roller, and regulates the amount of toner as a developer held on the surface of the developing roller to a considerably small amount, thereby reducing the surface of the developing roller. Form a thin layer of developer on. In addition, a blade of a developing roller formed of a stainless thin plate for spring having a thickness of 0.1 to 0.2 mm has been put into practical use.

[0004]

However, in the developer regulating means using the elastic blade such as the rubber elastic body or the stainless thin plate, the both ends of the elastic blade have low rigidity and the regulating force is inferior to the central portion. Therefore, both ends of the toner layer formed on the surface of the developing roller are thicker than the central part, and according to the experiments by the present inventors, when the urethane blade is used, the toner layer at both ends is 3. 5-7.0 μm
It turned out to be thick. As described above, when the elastic blade is used, it is difficult to make the toner layer formed on the surface of the developing roller have a uniform thickness in the entire width direction, and thus it is difficult to obtain a uniform image. Yes, again
The elastic blade has low wear resistance and is not necessarily satisfactory in terms of prolonging its life.

In order to solve the above problems of the elastic blade, the applicant of the present invention has disclosed an invention in which the blade constituting the developer regulating means is formed of a rigid member such as glass.
Proposed as No. 36277. By forming the blade from plate glass, abrasion resistance was improved and the life could be extended. Further, when the blade support accuracy is high, the amount of developer retained on the surface of the developing roller can be regulated uniformly in the width direction. However, it has been found that the accuracy of the support means for supporting the blade formed of a rigid member such as plate glass affects the developer amount regulation performance. That is, if the parallelism between the developing roller and the blade formed by the rigid member is changed, the pressure contact force of the blade is not uniform in the entire width direction, and the toner layer formed on the surface of the developing roller is uniform in the entire width direction. It is difficult to make it thick. Maintaining the processing accuracy and the assembly accuracy of the components of the supporting means for supporting the blade with high precision leads to an increase in manufacturing cost.

The present invention has been made in view of the above facts, and its main technical problem is to reduce the pressure contact force of the blade even if the parallelism between the developing roller and the blade formed by the rigid member changes to some extent. It is an object of the present invention to provide an electrostatic latent image developing device that can be made uniform in the entire width direction and can form a toner layer formed on the surface of a developing roller with a uniform thickness in the entire width direction.

[0007]

In order to solve the above-mentioned main technical problems, according to the present invention, a developing housing,
A developing roller for holding the developer on the surface in the developer holding area and conveying the held developer to the developing area and applying it to the electrostatic latent image; and the developer holding area. An electrostatic latent image developing device, comprising: a regulating means that acts on a peripheral surface of the developing roller in a developer regulating area located between the developing area and the developer, and regulates the amount of the developer retained on the peripheral surface. The regulating means includes a blade made of a rigid member, one surface of which is pressed against the surface of the developing roller, and one end of which is attached to the blade and the other end of which is a contact point of the blade on the upstream side in the rotation direction of the developing roller. A support member made of a flexible member extending substantially tangentially and fixed to the developing housing; and an elastic urging means for pressing the developing roller and the blade toward a contact point thereof. , Electrostatic latent The developing device is provided.

Further, according to the present invention, the supporting member made of the above-mentioned flexible member is made of a thin plate material having a width direction length corresponding to the width direction length of the blade, and an opening is provided in the middle portion. An electrostatic latent image developing device is provided.

Further, according to the present invention, a holder for holding the blade is provided, and the supporting member made of the flexible member is composed of two wire members each having one end connected to both ends in the width direction of the holder. An electrostatic latent image developing device is provided. Is provided.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an electrostatic latent image developing device constituted according to the present invention will be described below in more detail with reference to the accompanying drawings.

FIG. 1 shows an image generator equipped with an electrostatic latent image developing device constructed according to the present invention. The illustrated image generator includes a rotary drum 1 as an image carrier having a photosensitive layer on its peripheral surface. The rotary drum 1 is rotatably mounted in a machine body housing (not shown) by a rotary shaft 2. Around the rotating drum 1 which is rotated in the direction indicated by the arrow 3, a charging corona discharger 4 for sequentially charging the photosensitive layer of the rotating drum 1 to a specific polarity in the direction of rotation, and the charging corona discharger. A laser optical device 5 as an exposing means for forming an electrostatic latent image on the photosensitive layer of the rotary drum 1 which is charged with a specific polarity by an electrostatic latent image formed by the laser light emitted from the optical device 5. An electrostatic latent image developing device 6 for developing a toner image, a transfer corona discharger 7, a peeling corona discharger 8, a cleaning device 9, and a charge eliminating lamp 10 are provided.

The developing device 6 is provided with a developing housing 12 which can be made of synthetic resin. Inside the developing housing 12, a developing roller 16, a supplying means 18, an agitating means 20 and a regulating means 22 are provided. It is arranged. Further, although not shown, a toner cartridge containing toner is mounted on the developing housing 12.

The developing roller 16 is the developing housing 1 described above.
It includes a rotary shaft 24 rotatably mounted between the two side walls and a roller 26 fixed to the rotary shaft 24.
The rotating shaft 24 can be formed of a suitable metal material such as stainless steel. The roller 26 is made of a relatively soft and conductive material, for example, a conductive solid rubber such as urethane rubber. The roller 26 has an Asker C hardness of 60 to 85 in the illustrated embodiment.
The volume resistance of the roller 26 is set to about 10 ^{6 to} 10 ⁹ Ω · cm. The roller 26 of the developing roller 16 configured as described above is exposed through an opening formed in the developing housing 12 and is positioned to face the rotary drum 1. The peripheral surface of the roller 26 that constitutes the developing roller 16 is
It is pressed against the peripheral surface of the rotary drum 1, and the peripheral surface of the roller 26 is slightly elastically compressed in the pressed region. The rotating shaft 24 of the developing roller 16 is continuously driven to rotate in a direction indicated by an arrow 28 in FIG. By the above rotation of the rotary shaft 24, the roller 26 is also continuously driven to rotate in the direction indicated by the arrow 28, and the peripheral surface of the roller 26 is sequentially conveyed through the developer holding area 30, the developer regulating area 32 and the developing area 34. It

The supply means 18 includes a rotary shaft 36 rotatably mounted between both side walls of the developing housing 12.
An auxiliary roller 38 fixed to the rotating shaft 36 is included. The auxiliary roller 38 is made of a foam material such as foam silicon or foam urethane. The auxiliary roller 38 is pressed against the roller 26 of the developing roller 16. The hardness of the foam forming the auxiliary roller 38 is considerably smaller than the hardness of the roller 26 (for example, the Asker C hardness is about 35), and the auxiliary roller 38 is pressed against the roller 26, so that the auxiliary roller 38 becomes 0 It is desirable to be elastically compressed by about 0.15 to 0.25 mm. This auxiliary roller 38 is continuously driven to rotate in the direction indicated by arrow 39 in FIG. The stirring means 20 is the developing housing 12
And a stirring member 42 fixed to the rotating shaft 40.
It is continuously driven to rotate in a direction indicated by an arrow 44 in FIG. 1 by a driving means (not shown).

Next, the regulating means 22 will be described with reference to FIGS. 2 and 3. The restricting means 22 includes a blade 46 made of a rigid member that is pressed against the peripheral surface of the roller 26 of the developing roller 16, one end of which is attached to the other surface of the blade 46 and the other end of which is fixed to the developing housing 12. A supporting member 47 made of a flexible member and an elastic biasing means 48 for pressing one surface of the blade 46 in a direction of pressing against the peripheral surface of the roller 26 are provided.

At least one surface (that is, the surface pressed against the peripheral surface of the roller 26) of the blade 46 made of the above-mentioned rigid member extends along the peripheral surface of the roller 26 in the width direction (direction perpendicular to the paper surface in FIG. 1). It is composed of a plate-like member that is a flat surface that extends. The surface roughness of at least a region of the one side of the blade 46 which is pressed against the peripheral surface of the roller 26 is sufficiently small, and the center line average roughness Ra defined in JIS B 0601 is 6.00 or less, particularly 0.2.
It is preferably 0 or less, and particularly preferably 0.02 or less. If the surface roughness of the one surface of the blade 46 becomes excessive, the surface of the toner layer formed on the peripheral surface of the roller 26 constituting the developing roller 16 is not sufficiently flattened and tends to be non-uniform. There is. Therefore, a commercially available sheet glass is used as a suitable rigid material having a sufficiently small surface roughness and high hardness and abrasion resistance even though the blade 46 can be formed relatively inexpensively. Can be mentioned. The plate glass may have a thickness of about 3 mm. If it is desired to apply the required voltage to the blade 46 to control the charging characteristics of the toner, a conductive coating can be applied to one side of the sheet glass. As a plate glass with a conductive coating on one side, the trade name is "Nesa glass"
The glazing marketed as is may conveniently be used. Instead of the plate glass, the blade 46 may be made of a rigid member made of an appropriate metal plate such as stainless steel. In order to sufficiently reduce the surface roughness of one surface of the metal plate that constitutes the blade 46, one surface of the metal plate can be subjected to appropriate surface treatment, if necessary. If desired, the blade 46 may be constructed from a laminate of sheet glass and metal sheet,
One surface of the developing roller 16 which is brought into pressure contact with the roller 26 can be defined by the exposed surface of the plate glass.

The support member 47 made of the above flexible member is
In the illustrated embodiment, it is made of a thin steel plate 470, has a width direction length substantially corresponding to the width direction length of the blade 46, and a plurality of openings 471 are provided in the middle portion thereof. Thin steel plate 4 that constitutes the support member 47
One end of 70 is fixed to the other surface of the blade 46 by a fixing means such as an adhesive. The other end of the thin steel plate 470 forming the support member 47 is extended in the direction substantially tangential to the contact point with the blade 46 on the upstream side in the rotation direction of the roller 26 forming the developing roller 16, and is screwed to the developing housing 12. Is fixed by. In addition, a plurality of spring supporting protrusions 472 (six in the illustrated embodiment) are mounted on the rear surface of one end of the thin steel plate 470 forming the supporting member 47 at predetermined intervals in the width direction. The spring support protrusion 472 is located on the normal line passing through the contact point between the roller 26 and the blade 46. As described above, in the illustrated embodiment, the thin steel plate 470 forming the support member 47 made of a flexible member is provided with the plurality of openings 471 in the middle portion thereof, so that the rigidity thereof is lowered. However, in particular, the torsional rigidity is reduced. The plurality of openings 471 formed in the intermediate portion of the thin steel plate 470 forming the supporting member 47 serve as a passage for feeding the toner stirred by the stirring member 42 forming the stirring unit 20 to the supply unit 18 side. Also works.

The elastic biasing means 48 is used for the blade 4
A plurality of compression coil springs 480 (six in the illustrated embodiment) that press the back surface of one end of the thin steel plate 470 that constitutes the support member 47 mounted on the other surface of the six. One end of each of the plurality of compression coil springs 480 is fitted to each of the plurality of spring supporting protrusions 472 mounted on the back surface of one end of the thin steel plate 470 that constitutes the supporting member 47, and the other ends thereof are connected to the developing housing. A plurality of holes 121 (six holes in the illustrated embodiment) formed in the mounting portion 120 provided in the No. 12 are respectively penetrated to be projected from the outer surface of the mounting portion 120. Then, the closing plate 49 that closes the plurality of holes 121 formed in the mounting portion 120 is compressed by the compression coil spring 480 and attached by the screw 50. When the compression coil spring 480 is compressed and mounted in this manner, the pressing force of the compression coil spring 480 is applied to the blade 4 via the thin steel plate 470 forming the support member 47.
6 and one side of the blade 46 is the developing roller 16
Is pressed against the peripheral surface of the roller 26. At this time, the compression coil spring 480 that presses the thin steel plate 470 and the blade 46 is fixed to the roller 26 and the blade 4.
6, the spring supporting protrusion 4 located on the normal line passing through the contact point with 6.
Since it is fitted to 72, the pressing force acts toward the contact point between the roller 26 and the blade 46. The supporting member 47 for supporting the blade 46 is constituted by a thin steel plate 470 which is a flexible member in the illustrated embodiment, and moreover, since a plurality of openings 471 are provided in the middle portion thereof, Because of low rigidity, especially torsional rigidity,
Even if the parallelism between the developing roller 16 and the blade 46 is slightly deviated, the thin steel plate is easily twisted, so that the blade 46 on the peripheral surface of the roller 26 constituting the developing roller 16 is easily twisted.
The pressure contact force of is uniform in the entire width direction. The pressing force of the blade 46 against the peripheral surface of the roller 26 constituting the developing roller 16 can be appropriately set according to the thickness of the toner layer to be formed on the peripheral surface of the roller 26. When the pressure contact force increases, the thickness of the developer layer formed on the peripheral surface of the roller 26 decreases. On the other hand, if the pressure contact force becomes excessively large, smooth rotation of the roller 26 tends to be impeded. In the developing mode in the illustrated embodiment, the thickness of the toner layer formed on the peripheral surface of the roller 26 is usually about 20 to 30 μm, and in order to properly form the developer layer having such a thickness. Is the linear pressure of the blade 46 against the peripheral surface of the roller 26 (pressure per unit length in the width direction).
The pressure may be 4 to 50 g / cm.

The electrostatic latent image developing device according to the embodiment shown in FIGS. 1 and 2 is configured as described above, and its operation will be described below. With the start of operation of the electrostatic latent image developing device,
Roller 26 constituting the developing roller 16 and supply means 1
The auxiliary roller 38 and the stirring means 20 of No. 8 are rotationally driven in the directions indicated by the arrows by a driving means (not shown). The roller 26 forming the developer roller 16 is indicated by an arrow 28.
Is continuously driven to rotate in the direction indicated by
In the above, the supplying means 18 acts on the roller 26 to separate the toner held on the peripheral surface of the roller 26 until then from the roller 26, and the toner is newly supplied to the peripheral surface of the roller 26. In the developer regulation area 32, the blade 46 of the regulation means 22 acts on the developer retained on the peripheral surface of the roller 26 to regulate the toner retained on the peripheral surface of the roller 26 to a required amount and reduce the toner. Form in layers. In order to make the thickness of the toner layer formed on the peripheral surface of the roller 26 uniform in the entire width direction, the roller 2
Although it is important to make the pressure contact force of the blade 46 to the peripheral surface of 6 in the entire width direction uniform, in the illustrated embodiment, the support member 47 that supports the blade 46 is a thin steel plate that is a flexible member. 470, and since a plurality of openings 471 are provided in the middle portion thereof,
Because of its low rigidity, especially the torsional rigidity, even if the parallelism between the developing roller 16 and the blade 46 is slightly different, the thin steel plate 4
By easily twisting 70, the pressing force of the blade 46 against the peripheral surface of the roller 26 becomes uniform in the entire width direction.
Therefore, the thickness of the toner layer formed on the peripheral surface of the roller 26 can be made uniform in the entire width direction. The other end of the thin steel plate 470 which constitutes the support member 47 having the blade 46 attached to one end is extended substantially in the tangential direction of the contact point with the blade 46 on the upstream side in the rotation direction of the developing roller 16 to develop. Since it is fixed to the housing 12, it provides trail support for the rotation of the developing roller 16, so that the driving torque of the developing roller 16 can be reduced. Next, in the developing area 34, a developer is applied to the electrostatic latent image on the electrostatic photoconductor disposed on the peripheral surface of the rotary drum 1 to develop the electrostatic latent image into a toner image. . For example, an electrostatic latent image has a non-image area charged to about +700 V and a +
The image area is charged to about 120 V, and toner is attached to the image area (so-called reversal development).
The rotary drum 1 is continuously driven to rotate in the direction indicated by the arrow 3 in FIG. 1, so that the peripheral surface of the rotary drum 1 and the peripheral surface of the roller 26 of the developing roller 16 are moved in the same direction in the developing zone 34. . The moving speed V2 of the peripheral surface of the roller 26 is set to be slightly higher than the moving speed V1 of the peripheral surface of the rotating drum 1, and 1.2V1 ≦ V2 ≦ 2.
It is preferably 2V1. In this case, the roller 2
Sufficient toner is conveyed to the developing area 34 by 6 and the toner once attached to the non-image portion of the electrostatic latent image is appropriately peeled off by the sliding action of the peripheral surface of the roller 26 against the peripheral surface of the rotary drum 1. Thus, it is possible to obtain a good toner image having an appropriate development density and no fog. As the developer, a volume average particle diameter (Vol.
%: Toner having a volume average particle size or less and a toner having a volume average particle size or more are the same) having a volume resistance of about 8.0 to 12.0 μm and a volume resistance of 10 ⁸ Ω · cm or more Agents are preferably used.

FIG. 3 shows another embodiment of the regulating means constituting the electrostatic latent image developing device. The restricting means according to this embodiment includes a holder 51 that holds the blade 46.
It has. The holder 51 is provided with a recess 511 for fitting the blade 46. The depth of the recess 511 provided in the holder 51 is slightly smaller than the thickness of the blade 46. Therefore, when the blade 46 is fitted in the recess 511, one side of the blade 46 slightly protrudes. It has become. Further, coupling protrusions 512 are provided on both end surfaces of the holder 51 in the width direction. Although not shown, the holder 51 has a rear surface (a surface opposite to the surface on which the concave portion 511 is formed) with a predetermined interval in the width direction similar to the support member 47 shown in FIGS. 1 and 2. And a plurality of spring support protrusions are provided. On the other hand, in this embodiment, two wire members 520 and 520 are provided as the support member 52 made of a flexible member that constitutes the regulation means. The two wire members 520, 520 are provided with a connecting fitting 521 that engages with the connecting projection 512 provided on the holder 51 at one end thereof, and a fixing fitting 522 having a screw insertion hole at the other end. Each is installed. The two wire members 52, 52 configured in this manner are connected to the connecting fitting 52, respectively.
1 is engaged with the connecting projection 512 provided on the holder 51, and the fixing fittings 522 are fixed to the developing housing 12 by the screws 53. Since the supporting member 52, which is a flexible member that constitutes the regulating means in this embodiment, is composed of the two wire members 520 and 520, the torsional rigidity as the supporting member is extremely low, Even if the parallelism between the developing roller 16 and the blade 46 is deviated, the pressing force of the blade 46 to the peripheral surface of the roller 26 becomes uniform in the entire width direction. Therefore, the thickness of the toner layer formed on the peripheral surface of the roller 26 can be made uniform in the entire width direction.

[0021]

The electrostatic latent image developing device according to the present invention is constructed as described above, and supports the blade made of a rigid member which acts on the peripheral surface of the developing roller and regulates the amount of developer retained on the peripheral surface. Since the supporting member is made of a flexible member and has a low torsional rigidity, even if the parallelism between the developing roller and the blade is slightly different, the pressing force of the blade to the peripheral surface of the roller becomes uniform in the entire width direction. . Therefore, the thickness of the toner layer formed on the peripheral surface of the roller can be made uniform in the entire width direction. Further, since the other end of the supporting member having the blade attached to one end thereof is fixed to the developing housing by being extended substantially in the tangential direction of the contact point with the blade on the upstream side in the rotation direction of the developing roller. Since the trail is supported against the rotation of the developing roller, the driving torque of the developing roller can be reduced.

Further, according to the present invention, since the supporting member is made of a thin plate material which is a flexible member, and moreover, a plurality of openings are provided in an intermediate portion thereof, its rigidity, particularly torsion. Since the rigidity is low, even if the parallelism between the developing roller and the blade is slightly distorted, the thin steel plate can be easily twisted, so that the pressing force of the blade to the peripheral surface of the roller can be made uniform in the entire width direction. .

Further, according to the present invention, since the supporting member for supporting the holder for holding the blade is composed of two wire members, the torsional rigidity as the supporting member is extremely low, so that the developing Even if the parallelism between the roller and the blade is different, the pressure contact force of the blade with the peripheral surface of the roller can be made uniform in the entire width direction.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an image generator equipped with an electrostatic latent image developing device configured according to the present invention.

FIG. 2 is a perspective view of a principal part showing one embodiment of a regulating unit that constitutes the electrostatic latent image developing device shown in FIG.

FIG. 3 is a perspective view of a main part showing another embodiment of a regulating unit that constitutes the electrostatic latent image developing device.

[Explanation of symbols]

 1: Rotating drum 4: Corona discharger for charging 5: Laser optical part 6: Electrostatic latent image developing device 7: Corona discharger for transfer 8: Corona discharger for peeling 9: Cleaning device 10: Static elimination lamp 16: Development roller 18: Supplying Means 20: Stirring Means 22: Restricting Means 26: Developing Roller Rollers 30: Developer Holding Area 32: Developer Restricting Area 34: Developing Area 38: Auxiliary Roller of Supplying Means 46: Blade 47: Supporting Member 48: Elastic urging means 49: Closing plate 51: Holder 52: Support member 470: Thin steel plate 471: Opening 472: Spring support protrusion 480: Compression coil spring 520: Wire member 521: Connection fitting 522: Fixing fitting

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoyuki Ishida 1-2-2 Tamatsukuri, Chuo-ku, Osaka Mita Kogyo Co., Ltd. (72) Inventor Hiroshi Inui 1-2-2 Tamatsukuri, Chuo-ku, Osaka Mita Within Kogyo Co., Ltd.

Claims (3)

[Claims] 1. A developing housing, and a developer for holding a developer on a surface in a developer holding area provided in the developing housing and conveying the held developer to the developing area to apply it to an electrostatic latent image. A roller, and a regulating means for regulating the amount of the developer retained on the peripheral surface of the developing roller in the developer regulating area located between the developer retaining area and the developing area. In the electrostatic latent image developing device, the regulating means includes a blade made of a rigid member, one surface of which is pressed against the surface of the developing roller, and one end of which is attached to the blade and the other end of which is upstream in the rotational direction of the developing roller. A support member made of a flexible member that is fixed to the developing housing by being extended in a substantially tangential direction of a contact point with the blade on the side,
An electrostatic latent image developing device comprising: an elastic biasing unit that presses the developing roller and the blade toward a contact point between the developing roller and the blade. 2. The supporting member made of a flexible member is made of a thin plate material having a width direction length corresponding to the width direction length of the blade, and an opening is provided in an intermediate portion.
The electrostatic latent image developing device according to claim 1. 3. A holder for holding the blade,
The electrostatic latent image developing device according to claim 1, wherein the supporting member made of a flexible member is composed of two wire members each having one end connected to both ends in the width direction of the holder.