JP2001060041A - Developing device, process cartridge, developing unit cartridge and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device by which the force of a layer thickness regulating blade pressing to a developing roller is properly maintained while surely preventing toner leakage between a side seal and the layer thickness regulating blade. SOLUTION: The pressing member 64a of the layer thickness regulating blade 64 is formed to have a length by which an interstice of the width portion of the side seal is formed on the sides of both end end parts of a leaf spring 64b, and is attached at a position thereof. Then, a front face side blade side seal 112 made of a sponge is attached so as to come into contact with the side end surfaces of both sides of the pressing member 64a in the interstice thereof. Also, Teflon(R) felt that is the rubbing part of the side seal is formed to have a length to cover the front face side blade side seal 112, and is attached on the leaf spring 64b so as to cover the front face side blade side seal 112.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of a developing apparatus, a process cartridge, a developing cartridge, and an image forming apparatus provided with any one of them for developing using a developer which is charged fine particles. Belong to.

[0002]

2. Description of the Related Art In a developing device which uses a toner, which is charged fine particles, as a developer and electrostatically adheres the toner to an electrostatic latent image to perform development, there is a problem that the toner leaks from the developing device. is there. If the toner leaks from the developing device, the inside of the image forming apparatus main body equipped with the developing device becomes dirty, resulting in poor printing, and further, when the developing device is replaced, the hands and clothes of the worker become dirty. There was sometimes.

In particular, a non-magnetic one-component developing a thin layer of toner on a developing roller having a function of carrying and transporting the toner by using a layer thickness regulating blade and facing the electrostatic latent image. In the case of development, toner is likely to leak from around the rotating developing roller.

Conventionally, the above-described toner leakage has been prevented by providing a toner leakage prevention member inside the developing device. For example, in order to prevent toner leakage from both ends of the developing roller around the developing roller, a toner leakage preventing member called a side seal is rubbed against the peripheral surfaces of both ends of the developing roller, In order to prevent toner from leaking from the gap between the developing roller formed below and the opening of the toner container, a toner leak preventing member called a lower film is rubbed against the developing roller below the developing roller. . Further, in order to prevent toner from leaking from the gap between the developing roller formed above the developing roller and the opening of the toner container, the layer thickness regulating blade is pressed against the developing roller, and the layer thickness is reduced. The regulating blade has a function as a toner leakage preventing member.

The side seal has a structure in which a sliding member made of Teflon felt is attached to a urethane sponge. Urethane sponges are required to be sufficiently soft and have low compression set. Teflon felt is used for both securing the pressing force and reducing the rotational torque.

The lower film is made of PET (polyethyle).
ne terephthalate) sheet, urethane rubber or the like is used. Although urethane rubber can be expected to be softly pressed, it is necessary to press it with a sponge or the like from the back because it has no waist. Since the PET sheet is harder than the urethane rubber film, there is no need to press with a sponge or the like from the back, and there is an advantage that the assembling work is easier than the urethane rubber film.

[0007]

However, in the case where the method of rubbing the side seal against the peripheral surface of the developing roller is adopted, toner leakage or layer thickness control depends on the joining state between the layer thickness regulating blade and the side seal. There has been a problem that a pressing failure of the blade against the developing roller occurs.

In other words, when the layer thickness regulating blade interferes with the side seal, the pressure of the layer thickness regulating blade against the developing roller tends to be non-uniform at the end portion. If the pressing force with the side seal is reduced, toner leakage is likely to occur. As described above, there is a trade-off relationship between toner leakage based on the bonding state between the layer thickness regulating blade and the side seal and poor pressing of the layer thickness regulating blade against the developing roller, and it is very difficult to design.

For example, when a layer thickness regulating blade in which a pressing member such as rubber or resin is integrally provided on a plate spring made of stainless steel or the like is used, the length in the longitudinal direction of the plate spring and the pressing member are made equal. There is a method of preventing toner leakage by bringing a pressing member into contact with a side end surface of a side seal. Further, there is a method in which the length of the leaf spring and the pressing member in the longitudinal direction are made the same, and the upper end surface of the side seal is brought into contact with the pressing member to prevent toner leakage.

However, the former method has a problem that the toner easily leaks from between the layer thickness regulating blade and the side seal. In the latter case,
Initially, it was possible to prevent toner leakage.However, in long-term use, the Teflon felt fiber, which is a sliding member of the side seal, runs over the pressing member of the And a gap is created between the pressing member of the layer thickness regulating blade and the developing roller, and there is a problem that toner leaks from the gap.

In any of the systems, if the pressure between the layer thickness regulating plate and the side seal is increased in order to prevent toner leakage, the elastic force of the leaf spring does not work properly as a pressing force on the developing roller. The pressure on the roller may be stronger or weaker than the elastic force of the leaf spring. As a result, there is a problem that the pressure of the end of the layer thickness regulating blade against the developing roller changes, and the toner layer becomes unstable at the end.

In view of the above, the present invention provides a developing apparatus and a process capable of properly maintaining the pressing force of the layer thickness regulating blade against the developing roller while reliably preventing toner leakage between the side seal and the layer thickness regulating blade. It is an object to provide a cartridge, a developing device cartridge, and an image forming apparatus.

[0013]

According to a first aspect of the present invention, there is provided a developing device, wherein a developer carrier is rotatably disposed in an opening of a developing device housing for accommodating a developer. ,
A developing device that forms a visible image by making a thin layer of developer formed on the developer carrier face an electrostatic latent image, and is formed to extend in a longitudinal direction of the developer carrier. A leaf spring member, and a rubber or resin pressing member extending in the longitudinal direction of the developer carrier and integrally formed with the leaf spring member, wherein the pressing member is provided on a peripheral surface of the developer carrier. A developer layer thickness regulating member that is provided so as to be pressed and forms a thin layer of the developer, and includes at least a foamed elastic body;
A base portion attached to the developing device housing near both ends in the longitudinal direction of the opening of the developing device housing, and a peripheral surface mounted on the base portion and at both ends of the developer carrier is rubbed. And a developer leakage prevention member at both ends comprising a rubbing portion,
The developer layer thickness regulating member is such that the length in the longitudinal direction of the leaf spring member is longer than the length in the longitudinal direction of the pressing member, and the pressing member is provided at both ends in the longitudinal direction of the leaf spring member. The exposed portion of the surface of the spring member is provided at a position to form an exposed portion, the rubbing portion of the developer leakage prevention member at both ends is formed to extend so as to cover the exposed portion of the leaf spring member, It is characterized by being adhesively attached to the exposed part.

According to the first aspect of the present invention, the length of the developer layer thickness regulating member in the longitudinal direction of the leaf spring member is made longer than the longitudinal length of the pressing member. Suppresses the developer from entering the side end surface of the pressing member,
It is possible to reliably prevent toner from leaking from the side end surface of the pressing member. Further, the pressing member is provided at a position where the exposed portion of the surface of the leaf spring member is formed at both ends in the longitudinal direction of the leaf spring member, and the sliding portion of the developer leakage preventing member at both ends is provided with the exposed portion of the leaf spring member. Formed so as to cover the portion and adhesively attached to the exposed portion, so that a part of the rubbing portion does not enter between the pressing member and the developer carrier to form a gap, and such a gap is formed. To reliably prevent toner leakage. Also,
Since the rubbing portions of the developer leakage prevention members at both ends move together in accordance with the movement of the leaf spring member of the developer layer thickness regulating member, the movement of the leaf spring member of the developer layer thickness regulating member causes the developer leakage at both ends. There is no hindrance by the prevention member.

According to a second aspect of the present invention, in order to solve the above-mentioned problem, a developer carrier is rotatably disposed in an opening of a developing device housing for accommodating the developer. A developing device that forms a visible image by causing a thin layer of developer formed thereon to face an electrostatic latent image, and a leaf spring member formed to extend in a longitudinal direction of the developer carrier,
A rubber or resin pressing member formed integrally with the leaf spring member extending in the longitudinal direction of the developer carrying member,
The pressing member is provided so as to press against the peripheral surface of the developer carrying member, and a developer layer thickness regulating member that forms a thin layer of the developer, and near both longitudinal ends of the developing device housing opening. An end-end developer leakage prevention member attached to the developing device housing and rubbing against a peripheral surface on both end sides of the developer carrying member, wherein the developer layer thickness regulating member is a plate spring member. Is longer than the length of the pressing member in the longitudinal direction, and the pressing member is provided at a position where exposed portions of the surface of the leaf spring member are formed at both longitudinal ends of the leaf spring member. A foamed elastic material layer is adhesively attached to the exposed portion, and the developer leakage preventing members at both ends are formed so as to extend so as to cover the foamed elastic material layer, and the foamed elastic material layer is formed. It is characterized by being adhered and attached to.

According to the second aspect of the present invention, since the length of the leaf spring member of the developer layer thickness regulating member in the longitudinal direction is longer than the length of the pressing member in the longitudinal direction, from the back side of the leaf spring member. Suppresses the developer from entering the side end surface of the pressing member,
It is possible to reliably prevent toner from leaking from the side end surface of the pressing member. Further, the pressing member is provided at a position where an exposed portion of the surface of the leaf spring member is formed at both ends in the longitudinal direction of the leaf spring member, and a foamed elastic material layer is formed on the exposed portion to prevent developer leakage at both ends. Since the member is formed to extend so as to cover the foamed elastic material layer on the leaf spring member and is adhered and attached to the foamed elastic material layer, the developer leakage between the foamed elastic material layer and the developer leakage preventing members at both ends is prevented. To reliably prevent Further, since the rubbing portions of the developer leakage prevention member at both ends move together in accordance with the movement of the leaf spring member of the developer layer thickness regulating member, the movement of the leaf spring member of the developer layer thickness regulating member is developed at both ends. There is no hindrance by the agent leakage prevention member. Furthermore, even when the pressing member is worn, the amount of collapse of the foamed elastic body layer increases, and the pressing force of the pressing member against the developer carrier is not changed.

According to a third aspect of the present invention, in the developing device according to the first aspect, the pressing member has a length of a contact portion with the developer leakage preventing member at both ends. It is characterized in that it is set to 4 mm or more.

According to the third aspect of the present invention, the side end surfaces of the pressing member and the side end surfaces of the developer leakage preventing members at both ends are places where they are rubbed against each other without being bonded and attached. However, the length of the contact portion on both side end surfaces is 4 mm
It was confirmed that the setting described above can reliably prevent the developer from leaking from the contact portion. This is probably because the area of the contact portion is large enough to prevent the developer from leaking.

According to a fourth aspect of the present invention, in order to solve the above-mentioned problem, in the developing device according to the second aspect of the present invention, the pressing member includes a developer leakage preventing member at both ends and the foamed elastic material layer. The length of the contact portion is set to 4 mm or more.

According to the fourth aspect of the present invention, the side end surfaces of the pressing member and the side end surfaces of the developer leakage prevention member and the foamed elastic layer at both ends are not attached to each other, but are attached to each other. It is a place to be rubbed, but by setting the length of the contact portion on each side end surface to 4 mm or more,
It was confirmed that leakage of the developer from the contact portion could be reliably prevented. This is probably because the area of the contact portion is large enough to prevent the developer from leaking.

According to a fifth aspect of the present invention, in order to solve the above problem, in the developing device of the first aspect, the pressing member is formed of silicone rubber. And

According to the fifth aspect of the present invention, since the pressing member is formed of silicone rubber, good chargeability can be maintained, and the developer is appropriately frictionally charged. Moreover, as described above, when the developer leakage preventing members at both ends can secure a certain amount of crushing, even if the silicone rubber has been worn over a long period of use, the developer at both ends can be used in accordance with the degree of wear. The leakage prevention member is crushed, and the pressure of the developer layer thickness regulating member against the developer carrier is not changed. Therefore, the developer layer thickness is maintained uniform in the longitudinal direction of the developer carrier while reliably preventing the developer from leaking.

According to a sixth aspect of the present invention, in order to solve the above problem, in the developing device according to the first aspect, the pressing member has conductivity. And

According to the developing device of the present invention, since a conductive member is used as the pressing member, a predetermined voltage is applied between the pressing member and the developer carrying member.
Injection of charge into the developer or prevention of the developer of the opposite polarity from passing through the pressure contact portion between the pressing member and the developer carrier is prevented, thereby reducing the occurrence of print fog. Moreover, as described above, the pressing member of the developer layer thickness regulating member is provided at a position sandwiched between the developer leakage preventing members provided at both ends of the developer carrier. Therefore, the developer always exists in the pressure contact portion between the pressing member and the developer carrier over the entire area in the longitudinal direction of the developer carrier, and even when a voltage is applied to the pressing member, the developer is developed from the pressing member. No current flows directly to the agent carrier.

According to a seventh aspect of the present invention, in order to solve the above-mentioned problems, in the developing device according to any one of the first to sixth aspects, the developer is a polymerized toner produced by a polymerization method. It is characterized by the following.

According to the developing device of the present invention, since the polymerized toner produced by the polymerization method is used as the developer, the developing operation with high fluidity and high definition is performed. However, this polymerized toner tends to cause toner leakage due to its high fluidity, but as described above, toner leakage from both ends of the developer layer thickness regulating member is reliably prevented.

According to an eighth aspect of the present invention, in order to solve the above-mentioned problem, in the developing device according to any one of the first to seventh aspects, the developer carrier is formed of a conductive elastic body. Characterized in that it is a finished roller.

According to the developing device of the present invention, since a roller made of a conductive elastic material is used as the developer carrying member, a part of the developer leaking member at both ends is formed in the developer layer. When entering between the thickness regulating member and the developer carrying member, the developer is likely to leak due to damage to the surface of the developer carrying member. Since the layer thickness regulating member is provided on both side end surfaces of the pressing member, there is no such penetration between the developer layer thickness regulating member and the developer carrier, so that the surface of the developer carrier is damaged. To prevent the developer from leaking.

According to a ninth aspect of the present invention, a process cartridge is provided.
9. A process cartridge detachably formed in an image forming apparatus for solving the above-mentioned problem, comprising: a carrier for the electrostatic latent image; and a developing device according to claim 1. It is characterized by having.

According to the process cartridge of the ninth aspect, the process cartridge detachably formed in the image forming apparatus is provided with the developing device of any one of the first to eighth aspects. Even when the cartridge is attached or detached, the developer is reliably prevented from leaking. Further, depending on the developer leakage preventing members at both ends, the pressing of the developer layer thickness regulating member against the developer carrier does not change in the longitudinal direction of the developer carrier, so that a good developing operation is performed.

The developing device cartridge according to claim 10 is
In order to solve the above-mentioned problem, a developing device according to any one of claims 1 to 8 is formed so as to be detachable from an image forming apparatus or a process cartridge.

According to the tenth aspect of the present invention, the developing device according to any one of the first to eighth aspects is formed detachably with respect to the image forming apparatus or the process cartridge. The leakage of the developer is surely prevented even during the attachment and detachment. Further, depending on the developer leakage preventing members at both ends, the pressing of the developer layer thickness regulating member against the developer carrier does not change in the longitudinal direction of the developer carrier, so that a good developing operation is performed.

According to an eleventh aspect of the present invention, there is provided an image forming apparatus according to any one of the first to ninth aspects, wherein the developing device is a process cartridge, or the process cartridge is a third aspect. A developing device cartridge is provided.

According to the image forming apparatus of the eleventh aspect,
Since the developing device according to any one of claims 1 to 9 or the process cartridge according to claim 9 or the developing device cartridge according to claim 10 is provided, the developer does not leak and the inside of the image forming apparatus main body is not generated. Is not contaminated by the developer. Further, depending on the developer leakage preventing members at both ends, the pressing of the developer layer thickness regulating member against the developer carrier does not change in the longitudinal direction of the developer carrier, so that a good image forming operation is performed.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. First, an overview of the entire image forming apparatus according to the present embodiment will be described.

FIG. 1 is a sectional view showing a schematic configuration of a laser beam printer 1 as an embodiment of the image forming apparatus of the present invention. In FIG. 1, the laser beam printer 1 includes a feeder unit for feeding paper (not shown) at the bottom of a main body case 2. The feeder unit includes a paper pressing plate 10 that is pressed by a spring (not shown), a paper feeding roller 11, and a friction separating member 14. The uppermost sheet is separated between the feed roller 11 and the friction separating member 14 by the rotation of the roller, and the sheet is supplied at a predetermined timing.

A pair of registration rollers 12 and 13 are rotatably supported on the downstream side in the sheet transport direction by the rotation of the sheet supply roller 11 rotating in the direction of the arrow in FIG. The sheet is conveyed to a transfer position formed by the transfer roller 21 at a predetermined timing.

The photosensitive drum 20 is made of a positively chargeable material, for example, an organic photoreceptor mainly composed of positively chargeable polycarbonate. More specifically, the photosensitive drum 20 has, for example, a cylindrical aluminum sleeve as a main body, and has a predetermined thickness (for example, about 20 μm) in which a photoconductive resin is dispersed in polycarbonate on an outer peripheral portion thereof. It is composed of a hollow drum on which a conductive layer is formed, and is rotatably supported by the main body case 2 with the cylindrical sleeve grounded. Further, the photosensitive drum 20 is driven to rotate in a direction indicated by an arrow by driving means (not shown).

The charger 30 is composed of a scorotron type charger for positive charging for generating corona discharge from a charging wire made of, for example, tungsten.

The laser scanner unit 40 includes a laser generator (not shown) that generates a laser beam L for forming an electrostatic latent image on the photosensitive drum 20, and a polygon mirror (pentahedral mirror) 41 that is driven to rotate. , A pair of lenses 42 and 4
5 and reflection mirrors 43, 44 and 46.

In the developing device 50, a toner accommodating chamber 52 as a developer chamber is formed in a case 51 as a developing device housing. In the toner accommodating chamber 52, an agitator 53 and a cleaning member 54 are provided with a rotating shaft 55. It is provided rotatable around. The toner accommodating chamber 52 accommodates a positively chargeable nonmagnetic one-component developer having electrical insulation. The rotation shaft 55 of the toner storage chamber 52
Light transmitting windows 56 are provided on the side walls located at both ends of the light emitting element. On the photosensitive drum 20 side of the toner accommodating chamber 52, a developing chamber 57 that communicates with the toner accommodating chamber 52 through the opening A to perform development is formed, and a supply roller 58 and a developing roller 59 as a developer carrier are rotated. Pivot as possible.
The toner on the developing roller 59 is regulated to a predetermined layer thickness by a thin plate-like elastic layer thickness regulating blade 64 and is used for development.

Here, a developing roller 59 as a developer carrying member is a cylindrical metal formed of conductive silicone rubber containing fine particles of conductive carbon on a metal core formed of stainless steel or the like. A base material is provided, and a coat layer of a resin or rubber material containing fluorine is formed on the base material. The base of the developing roller 59 does not necessarily have to be made of conductive silicone rubber, and may be made of conductive urethane rubber.

As shown in FIGS. 13A and 13B, a layer thickness regulating blade 64 as a developer layer thickness regulating member has a support portion 64c made of iron or stainless steel.
, A thin plate-shaped leaf spring 64b made of phosphor bronze or stainless steel is attached, and a pressing member 6 made of silicone rubber is further placed on the leaf spring 64b.
4a is attached. Note that FIG.
(B) is a diagram viewed from the arrow A side shown in FIG. 13 (C), that is, the front side, and FIG. 13 (A) is a diagram viewed from the opposite back surface side.

The support portion 64c is provided with the boss hole 115 shown in FIG. 13A and the boss 1 on the case 51 side shown in FIG.
15A and attached to the case 51 by screwing it through a screw hole 116 shown in FIG. Then, by attaching the developing roller 59 to the case 51 thereafter, the pressing member 64a comes into pressure contact with the peripheral surface of the developing roller 59 by the elastic force of the leaf spring 64b and the elastic force of the silicone rubber itself. This allows
The thickness of the toner layer on the developing roller 59 is regulated to a desired value.

As can be seen from FIGS. 13A and 13B, the layer thickness regulating blade 64 in this embodiment is such that the longitudinal length of the support portion 64c and the leaf spring 64b is
4a is formed longer than the length in the longitudinal direction, and the pressing member 64a is provided with a distance between the right end thereof and the right end of the leaf spring 64b,
And it is attached to a position where the distance between the left end thereof and the left end of the leaf spring 64b is substantially equal. Thereby, the leaf spring 64
Exposures at which the surface of the leaf spring 64b is exposed are formed at both ends of the b. In the present embodiment, as shown in FIG. A front side blade side seal 112 as an elastic layer is attached with a double-sided tape. Further, as shown in FIG. 13A, on the back side, a back side blade side seal 111 is attached to the leaf spring 64b by a double-sided tape. Each of the front-side blade side seal 112 and the back-side blade side seal 111 is formed of a sponge softer than a urethane sponge.

The toner accommodated in the toner accommodating chamber 52 is a positively charged non-magnetic one-component developer, and a styrene-acrylic resin formed into a spherical shape by a suspension polymerization method, such as carbon black or the like. The toner base particles have a particle diameter of 6 μm to 10 μm and an average particle diameter of 8 μm to which a well-known coloring agent and a charge control agent such as nigrosine, triphenylmethane, and quaternary ammonium salt are added. The toner is configured by adding silica as an external additive to the surface of the toner base particles.

The transfer roller 21 is rotatably pivotally supported,
It is made of a conductive foamed elastic body made of silicone rubber or urethane rubber. The transfer roller 21 is configured to reliably transfer the toner image on the photosensitive drum 20 to the paper by the applied voltage.

The fixing unit 70 includes the registration roller 12
The heating roller 71 and the pressing roller 72 are provided on the further downstream side in the sheet conveyance direction from the sheet feeding roller 13 to the pressure contact portion between the photosensitive drum 20 and the transfer roller 21. The toner image transferred to the sheet is heated and pressed while being conveyed by the heating roller 71 and the pressing roller 72 and is fixed on the sheet.

A pair of transport rollers 73 and a paper discharge roller 74 for paper transport are provided on the downstream side in the transport direction of the fixing unit 70, respectively, and a paper output tray 75 is provided on the downstream side of the paper discharge roller 74. Have been.

The above-described photosensitive drum 20, transfer roller 21, charger 30, and developing device 50 are housed in a drum cartridge 2a, and the drum cartridge 2a is detachably attached to the laser beam printer 1. Is provided. Further, the developing device 50 is provided detachably with respect to the drum cartridge 2a (process cartridge of claim 10) as a developing device cartridge.

In the laser beam printer 1 of the present embodiment as described above, the surface of the photosensitive drum 20 is
When the laser beam L modulated according to image information is emitted from the laser scanner unit 40, an electrostatic latent image is formed on the surface of the photosensitive drum 20.
This electrostatic latent image is visualized with toner by the developing device 50, and the visible image formed on the photosensitive drum 20 is transported by the photosensitive drum 20 to a transfer position. At the transfer position, the paper is supplied via the paper feed roller 11 and the registration rollers 12 and 13, and the visible image is transferred to the paper by a transfer bias applied by the transfer roller 21. The toner remaining on the photosensitive drum 20 after the transfer is collected in the developing chamber 57 by the developing roller 59.

Next, the sheet is conveyed to the fixing unit 70, is nipped and conveyed by the heating roller 71 and the pressing roller 72 of the fixing unit 70, and the visible image on the sheet is pressed and heated to be fixed on the sheet. You. Then, the sheet is discharged to the discharge tray 75 above the laser beam printer 1 by the pair of transport rollers 73 and the discharge rollers 74, and the image forming operation is completed.

(Seal Structure in Developing Apparatus) Next, a sealing structure using a developer leakage prevention member in the developing apparatus 50 of the present embodiment will be described with reference to FIGS. I do.

FIGS. 2 (A), 3 (A), 4 (A), 5 (A), 6 (A), 7 (A), 8 (A), 1
1 (A), FIG. 12 and FIG.
5 is a partially cutaway perspective view showing a seal portion of a case 51 in FIG. 2 (B), FIG. 3 (C), FIG. 4 (C), FIG. 5 (B), FIG. 6 (B), FIG. 7 (B), FIG.
1 (B) and FIG. 14 (C) are views showing the seal portion viewed from the direction of arrow B shown in each of the partially cutaway perspective views. FIG. 3B is a sectional view taken along line CC of FIG.
FIG. 8B is a diagram showing the seal portion viewed from the direction of arrow A shown in FIG. 4A, FIG. 8B is a diagram showing the seal portion viewed from the direction of arrow A shown in FIG. Is a front view showing a seal portion of the case 51 at a stage where the upper seal is attached, FIG. 10 is a view showing the seal portion viewed from the direction of arrow B shown in FIG. 9, and FIG. 13 (B) is a diagram of the layer thickness regulating blade viewed from the front side, FIG. 13 (C) is a diagram showing a seal portion viewed from the direction of arrow B similarly to FIG. 11 (B), and FIG. (B) is FIG. 14 (A)
FIG. 14 is a diagram showing a seal portion viewed from the direction of arrow A shown in FIG.
(D) is a sectional view taken along line DD of FIG. 14 (C), and FIG.
Is a plan view showing the lower film and its surroundings,
FIG. 15 (B) is a view showing the bonding surface of the lower film, and FIG.
14A is a partially cutaway perspective view showing a seal portion of the case 51 on the opposite side to FIG. 14A, and FIG.
FIG. 5 is a view showing a seal portion viewed from the direction of arrow B as shown in FIG.

First, in FIG. 2A, an area indicated by oblique lines is an area where a seal member described below is attached by a double-sided tape, and a side-side seal attachment area 100 along the circumferential direction of the developing roller 59. , Developing roller 5
9 is divided into a lower seal mounting area 101 along the longitudinal direction of the developing roller 59. Side seal mounting area 100 and lower seal mounting area 101
Is subjected to a degreasing treatment in order to enhance the adhesiveness of the double-sided tape.

The developing roller 59 is arranged so that its end face is close to the side face 51a in the developing roller accommodating portion of the case 51 shown in FIG. FIG. 2 (B)
The center point Q shown in FIG. 7 indicates the position of the rotation center axis of the developing roller 59. The supply roller 58 is attached to a supply roller housing provided at a position behind the developing roller housing, as indicated by a two-dot chain line in FIG.

Next, as shown in FIGS. 3A, 3B, and 3C, an end surface of the bottom surface 51b of the developing roller housing portion following the lower seal mounting region 101 on the side seal mounting region 100 side. 51c, and the side edge seal 102 is attached to the side side seal mounting area 1 with a double-sided tape.
Attach it to 00. The double-sided tape is attached to the bottom of the side edge seal 102, and the side edge seal 10
The end face 2 is pressed against the end face 51c of the bottom surface portion 51b on the side-side seal mounting area 100 side to be brought into close contact therewith. As shown in FIG. 3B, the side seal mounting area 100 has a bottom surface portion 51 in consideration of the thickness of a side seal described later.
b, and a step having an end face 51c is formed between the bottom face 51b and the side seal mounting area 100. Side seal installation area 1
00, the side seal 10 as shown by the dotted line in FIG.
4, the end face 51c is attached to the side seal 10
4 comes into contact with the end face of the side seal 104.
, A urethane sponge having relatively high rigidity among sponges is used, so that the adhesiveness to the resin forming the case 51 is weakened, and the end face 51 c and the side seal 104 are used.
Toner enters the contact portion with the end surface of the toner, and toner leakage occurs. The intrusion of the toner is not limited to the intrusion through the bottom surface 51b, but also from the supply roller housing. Therefore, in the present embodiment, the side edge seal 102 formed of a sponge softer than the urethane sponge is brought into close contact with the end face 51c to reliably prevent such intrusion of the toner.

Next, as shown in FIGS. 4A, 4B and 4C, the film 103 for attaching the upper side seal is formed.
To the case 51 using a double-sided tape. A blade side seal for preventing toner leakage from both end portions is attached to the layer thickness regulating blade 64, and an upper side seal for improving adhesion to the blade side seal is provided on the case 51 side. It is attached. This upper side seal is attached so as to be superimposed on the film 103 shown in FIG. 4B, but if there is no film 103, the bonding area of the upper side seal to the case 51 is indicated by hatching in FIG. 4B. Only the region shown indicates lack of stability. Therefore,
In the present embodiment, the PET film 103 is
1 to secure the bonding area of the upper side seal.

Next, as shown in FIGS. 5A and 5B,
In order to prevent toner from leaking from the end of the developing roller 59, a side seal 104 constituting a base material of a developer leak preventing member at both ends is attached to the side seal attaching area 100 with a double-sided tape. The side seal 104 is formed of a urethane sponge (trade name: Poron, manufactured by Rogers INOAC) having relatively high rigidity among sponges, and is compressed when the developing roller 59 is attached so as to exert a predetermined pressing force. It has a certain thickness. With such a configuration, Teflon felt, which is the uppermost layer of the both-end developer leakage prevention member described below,
The developing roller 59 can be pressed with a predetermined pressing force.

Further, in the present embodiment, FIG.
As shown in (1), the side end surface of the supply roller 58 is configured to rub against the side end surface of the side seal 104, so that toner leakage from between the supply roller 58 and the side seal 104 is prevented.

Next, as shown in FIGS. 6A and 6B,
In order to prevent toner leakage from the boundary between the lower seal mounting area 101 and the side seal mounting area 100 and toner leakage from a gap between a movable section of the lower seal and the lower seal mounting area 101, which will be described later. The side seal 105 is attached to the lower seal mounting area 10 with a double-sided tape.
Attach to one end. The lower side seal 105 is formed of a soft urethane sponge, and a double-sided tape is attached to the bottom surface of the lower side seal 105. The end face on the side seal 104 side is attached so as to overlap in a partial area W0 as shown in FIG. 6B, and the lower side seal 105 is brought into close contact with the side seal 104 by pressing.
In the present embodiment, the overlapping area W0 is set to about 2 mm.

Next, as shown in FIGS. 7A and 7B,
Adhesive surface of side seal 104 of case 51 and film 1
The edge seal 106 is attached from the stepped portion E formed between the adhesive surface 03 and the upper surface of the side seal 104. The edge seal 106 is formed of a soft urethane sponge, and is adhered to the step portion E and the upper end surface of the side seal 104 by attaching a double-sided tape to the bottom surface. By providing such an edge seal 106, the lower end face of the upper side seal attached to the film 103 and the blade side seal attached to the layer thickness regulating blade, to which the double-sided tape is not attached, is brought into contact with the edge seal 106. Thus, a contact portion between the sponge and the sponge can be formed to reliably prevent the toner from leaking.

Next, as shown in FIGS. 8 (A), 8 (B) and 8 (C), the upper side seal 107 is attached to the film 103 in order to improve the adhesion to the blade side seal described later.
And attached to the case 51 with double-sided tape. The upper side seal 107 is formed of a soft urethane sponge, and is provided at a position in contact with a blade side seal described later. With this configuration, the contact portion between the upper side seal 107 and the blade side seal is
The sponge is in contact with the sponge, so that toner leakage can be reliably prevented.

Next, as shown in FIGS. 9 and 10, in order to prevent toner from leaking from an upper position behind the mounting portion of the layer thickness regulating blade 64, the layer thickness regulating blade 64 is formed to extend in the longitudinal direction. The mounted upper seal 108 is attached. The upper seal 108 is formed of a soft urethane sponge. With this upper seal 108,
It is possible to reliably prevent toner leakage due to toner spraying in the toner storage chamber or toner leakage when the developing device 50 is turned upside down.

Next, as shown in FIGS. 11A and 11B, an intermediate film 109 constituting an intermediate layer of a developer leakage preventing member at both ends is attached on the side seal 104. The film 109 is formed of PET, and is attached to the side seal 104 with a double-sided tape. As shown in FIG. 11A, the intermediate layer film 109 is wider than the side seal 104, and has a protruding portion whose end protrudes toward the center of the case 51. With this configuration, it is possible to reduce the toner density near the pressure contact portion between the Teflon felt attached to the intermediate layer film 109 and the developing roller, as described later, and to reduce the toner pressure on the pressure contact portion. be able to. As a result, the developing roller 5 of the side seal 104
The toner leakage can be reliably prevented without increasing the pressing force to the toner 9 more than necessary.

As shown in FIG. 11A, a cutout portion 109a is provided at the projecting portion of the intermediate layer film 109 from the center of the case 51 along the longitudinal direction of the developing roller 59. Developing roller 59 and supply roller 5
The intermediate layer film 109 is prevented from being torn by the deformation caused by the load caused by the rotation of the motor 8.

Next, as shown in FIG. 12, the side edge seal 110 is attached to the upper part of the intermediate film 109 using a double-sided tape. This side edge seal 110
Is formed of a sponge, and prevents a gap from being formed between a leaf spring of the layer thickness regulating blade 64 described later and the intermediate layer film 109, thereby preventing toner leakage.

Next, as shown in FIG. 13A, the back side blade side seal 111 is attached to the leaf spring 64b attached to the support portion 64c of the layer thickness regulating blade 64 with a double-sided tape. The lateral length W1 of the back side blade side seal 111 along the longitudinal direction of the layer thickness regulating blade 64 is determined by the pressing member 64 from the side end of the leaf spring 64b.
a is formed wider than the interval W2 to the side end of
It covers from the side end of the leaf spring 64b to a position corresponding to the end of the pressing member 64a. When the layer thickness regulating blade 64 is attached to the case 51, the leaf spring 64b receives a pressing force from the upper side seal 107 and the back side blade side seal 111 as shown in FIG. By providing the side blade side seal 111 in the above region, not only the leaf spring 64b, but also
Since the end of the pressing member 64a is also pressed, the leaf spring 64b is not bent. Therefore, it is possible to prevent toner leakage due to the bending of the leaf spring 64b. Also,
The longitudinal length H1 of the back side blade side seal 111 along the lateral direction of the layer thickness regulating blade 64 is the leaf spring 6
4b covers the entire area of the leaf spring 64b in the short direction. The double-sided tape is attached to the back surface of the back-side blade side seal 111, and the front surface is as shown in FIG.
As shown in FIG. Since the back side blade side seal 111 is formed of a soft urethane sponge, the contact portion between the back side blade side seal 111 and the upper side seal 107 is a sponge-to-sponge contact portion. Also,
The lower end surface of the back side blade side seal 111 is shown in FIG.
As shown in (C), it is in contact with the side edge seal 106. Accordingly, the contact portion between the back side blade side seal 111 and the side edge seal 106 is also a contact portion between sponges. As described above, the boundary between the back side blade side seal 111 and other members is a contact portion between the sponge and the sponge except for the adhesive surface with the leaf spring 64b, thereby reliably preventing toner leakage. .

On the other hand, on the front side of the leaf spring 64b on which the pressing member 64a is provided, as shown in FIG. 13B, a front blade side seal 112 is provided on both sides so as to contact both ends of the pressing member 64a. Attached by tape. The front blade side seal 112 is formed of a soft urethane sponge. Teflon felt, which will be described later, is mounted on the front blade side seal 112. The thickness when the front blade side seal 112 and Teflon felt are combined is as shown in FIG.
As shown in (1), it is configured to be thicker than the pressing member 64a in consideration of a certain amount of crushing. With this configuration, even when the pressing member 64a is worn, the pressing force of the pressing member 64a at both ends on the developing roller 59 is not changed, and the toner from the pressing contact portion between the pressing member 64a and the developing roller 59 is not changed. Leakage can be reliably prevented.

The front blade side seal 1
As shown in FIG. 13B, 12 is attached so as to be in contact with the side end surface of the pressing member 64a.
In the side end surface, a hatched portion shown in FIG. 17 is a contact portion 64 d with the front blade side seal 112.
The length W5 of the contact portion 64d in the direction along the surface of the leaf spring 64b is 4 m in the present embodiment.
m or more. Since the contact portion 64d is not attached to the front side blade side seal 112 with a double-sided tape or the like, the front side blade side seal 11 is moved in accordance with the movement of the leaf spring 64b of the layer thickness regulating blade 64.
2 would be rubbed. However, by setting the length W5 of the contact portion 64d to 4 mm or more, the front blade side seal 11
2, the contact area with the contact portion 2 becomes sufficiently large, and toner leakage from the contact portion can be reliably prevented for a long period of time.

On the other hand, the length W5 of the contact portion 64d
Was shorter than 4 mm, and the contact portion 6
The contact area of the 4d with the front blade side seal 112 was insufficient, and in a long-term use, a small amount of toner leakage might occur.

The shape of the side end surface of the pressing member 64a is a so-called kamaboko shape as shown in FIG. 17, and the pressing portion against the developing roller 59 has a round shape. However, since the mounting portion of the pressing member 64a to the leaf spring 64b has a surface perpendicular to the leaf spring 64b, it can be formed as a rectangular contact portion 64d as shown in FIG. W5 can be secured. Therefore, as long as the length W5 can be secured, the shape of the side end surface of the pressing member 64a is not limited to the shape shown in FIG.

As described above, according to the configuration of the present embodiment, not only can toner leakage from the pressure contact portion between the pressing member 64a and the developing roller 59 be reliably prevented, but also
It is possible to reliably prevent toner from leaking from a contact portion between the pressing member 64a and the front blade side seal 112.

Next, as shown in FIGS. 14 (A), (B) and (C), the Teflon felt 113 as the rubbing portion of the developer leakage preventing member at both ends is attached to the plate spring of the layer thickness regulating blade 64. 64b, front blade side seal 112, intermediate layer film 109, and side seal mounting area 100
Using double-sided tape. On the layer thickness regulating blade 64, as shown in FIGS. 14 (B) and 14 (C), the tip of Teflon felt is attached to the leaf spring 64b, and the subsequent portion covers the front side blade side seal 112. Paste. With such a configuration, the pressing member 6 of the layer thickness regulating blade 64 is
4a can be reliably prevented from leaking from both ends.

That is, in the present embodiment, FIG.
As shown in (A) and (B), the length in the longitudinal direction of the leaf spring 64a is configured to be longer than the length in the longitudinal direction of the pressing member 64a, so that the side end surface of the pressing member 64a and the Teflon felt 113 are formed. Intrusion of the toner from the back surface side of the leaf spring 64b into the contact portion is prevented by the leaf spring 64b covering the contact portion, thereby reliably preventing toner from leaking in this direction. Therefore, compared to the conventional example in which the plate spring and the pressing member have the same longitudinal length and are in contact with the side end surface of the side seal, there is no toner leakage from the contact portion between the pressing member and the side seal, and Demonstrates excellent effects.

In this embodiment, FIG.
As shown in (B), (C), and (D), the Teflon felt 113 is configured to ride on the position on the side end surface side of the pressing member 64a and on the leaf spring 64b.
The Teflon felt hair is pressed against the pressing member 64a and the developing roller 5
As a result, no gap is formed between the pressing member 64 a and the developing roller 59.
As a result, toner leakage from between the pressing member 64a and the developing roller 59 can be reliably prevented. Therefore,
The length of the pressing member in the longitudinal direction is extended to a position on the side end surface outside the side seal, and the side member is brought into contact with the pressing member from the upstream side in the rotation direction of the developing roller. The effect of preventing toner from leaking from between the roller 59 can be significantly increased. Further, as described above, by configuring the Teflon felt 113 to ride on the leaf spring 64b, the Teflon felt 113 moves together with the movement of the leaf spring 64b of the layer thickness regulating blade 64, and the layer thickness is increased. Regulator blade 64
Does not hinder the movement of the leaf spring 64b. Therefore,
Compared to the two conventional examples in which the pressing force between the layer thickness regulating blade and the side seal was increased to prevent toner leakage and the pressing force of the layer thickness regulating blade against the developing roller was changed, The configuration of the embodiment has a remarkably excellent effect in that the pressing force of the layer thickness regulating blade against the developing roller can always be appropriately maintained.

Further, in the present embodiment, FIG.
As shown in (C) and (D), Teflon felt 113
The front side blade side seal 112 as a foamed elastic material layer formed of a sponge different from the side seal 104 as a base material of the developer leakage prevention member on both ends is formed by a leaf spring 64b and Teflon. This is provided between the felt 113 and the leaf spring 64b and the Teflon felt 113 with a double-sided tape. As a result, even if the Teflon felt 113 is pressed against the developing roller 59 with a sufficient pressing force so as to reliably prevent toner leakage from both ends of the developing roller 59, the repulsive force of this portion is reduced by an appropriate amount. The pressing force of the pressing member 64 a of the layer thickness regulating blade 64 against the developing roller 59 is absorbed by the front side blade side seal 112
9 does not become weak on both end sides.

In particular, when silicone rubber having excellent chargeability is used as the material of the pressing member 64a of the layer thickness regulating blade 64 as in this embodiment, there is a problem that the silicone rubber is scraped off over a long period of use. Occurs.
However, even in such a case, the amount of crushing of the front side blade side seal 112 attached to the leaf spring 64b increases by the amount of the silicon rubber shaved, and the pressing member 64a at both ends of the developing roller 59 with respect to the developing roller 59 The pressure does not change. That is, even when the silicone rubber of the pressing member 64a is shaved, toner leakage from between the developing roller 59 and the pressing member 64a can be reliably prevented.

In this embodiment, the thickness in the W4 direction shown in FIG. 14D is 1.1 mm for the front blade side seal 112, 0.8 mm for the Teflon felt 113, and 1.5 mm for the pressing member 64a. The combined thickness of the front-side blade side seal 112 and the Teflon felt 113 is larger than the thickness of the pressing member 64a, and the crushing amount is 0.4 mm.
The reason for setting such a value is that, as a result of the experiment, if the thickness of the front-side blade side seal 112 is too large, the repulsive force increases as the amount of crushing increases, and both ends of the developing roller 59 This is because it has been confirmed that the pressing force of the pressing member 64a against the developing roller 59 changes.

In this embodiment, the Teflon felt 113 and the front blade side seal 112 are pressed against the side end surface of the pressing member 64a in the direction of arrow E in FIG. ing. With this configuration, the pressing member 64a, the Teflon felt 113, and the front-side blade side seal 112
The toner can be reliably prevented from leaking from a contact portion with the toner. In the present embodiment, it has been confirmed that toner can be reliably prevented from leaking without adversely affecting the pressing force of the pressing member 64a against the developing roller 59 when crushed by about 0.5 mm.

In this embodiment, in particular, a part of the side end face of the Teflon felt 113 contacts the contact portion 64d of the pressing member 64a shown in FIG.
The contact length W5 is the same as the length for the front blade side seal 112 as shown in FIG. 14B, and is set to 4 mm or more. Accordingly, not only the front blade side seal 112 but also the contact area between the contact portion 64d of the pressing member 64a and the side end surface of the Teflon felt 113 becomes sufficiently large, and the pressing member 64a and the Teflon felt 113 and the front blade side seal 112 are sealed. 11
2 can be more reliably prevented from leaking from the contact portion.

In this embodiment, the thickness regulating blade 6
Although a conductive silicone rubber is used as the pressing member 64a, the area where the pressing member 64a is provided is:
Since the positions are inside the side seals 104 at both ends, the toner is always sandwiched between the pressing member 64 a and the developing roller 59 over the entire area in the longitudinal direction of the developing roller 59. Even when a voltage is applied between the developing roller 59 and the developing roller 59, a current does not flow directly from the layer thickness regulating blade 64 to the developing roller 59.

As described above, by applying a voltage to the layer thickness regulating blade 64, charge is injected into the toner to assist charging of the toner, or a toner of the opposite polarity is pressed by a voltage of the same polarity as the toner. Since it is possible to make it difficult to pass through the pressure contact portion between the member 64a and the developing roller 59, it is possible to reduce the occurrence of print fog.

Next, FIG. 15A, FIG. 16A,
As shown in (B), a lower film 114 as a lower end developer leakage prevention member is attached. Lower film 11
4 is a PET sheet or a urethane rubber film. In this embodiment, a PET sheet is used. The lower film 114 is, as shown by oblique lines in FIG.
A part of the lower seal mounting area 101, a part of the front edge 51 d of the case 51, and a part of the lower side seal 105 are attached using a double-sided tape. in this way,
Since the adhesive surface of the lower film 114 includes not only the lower seal mounting area 101 but also the area of the width W3 and the height H2 of the front edge 51d, it is difficult to peel off. Accordingly, even when the pressing force between the developing roller 59, the lower film 114 and the Teflon felt 113 is increased to some extent, the peeling of the lower film 114 can be reliably prevented. Also, both ends of the lower film 114 are as shown in FIG.
As shown in FIG. 16 (B) and FIG. 16 (A), the user rides on the Teflon felt 113. With this configuration, when the developing roller 59 is mounted, the lower film 114 is pressed toward the Teflon felt 113 by the developing roller 59, and the gap between the Teflon felt 113 and the lower film 114 is eliminated.
It is possible to reliably prevent toner from leaking from the contact portion between the Teflon felt 113 and the lower film 114.

As described above, in the developing device 50 of this embodiment, toner leakage from the upper portion, both ends, and the lower portion of the developing roller 59 can be reliably prevented. In particular, the length of the pressing member 64a of the layer thickness regulating blade 64 in the longitudinal direction is made shorter than that of the leaf spring 64b, and the Teflon felt 113 rides on the leaf spring 64b on both end surfaces of the pressing member 64a. Since the front side blade side seal 112 made of sponge is provided between the Teflon felt 113 and the leaf spring 64b, the pressing force of the pressing member 64a against the developing roller 59 is not changed. It is possible to reliably prevent toner leakage at both ends. When a polymerized toner having a fine particle diameter and high fluidity is used as in the present embodiment, it is possible to reliably prevent toner leakage, which is extremely effective.

In the above description, the front blade side seal 112 is provided on the leaf spring 64b of the layer thickness regulating blade 64, and the front blade side seal 112 is covered with the Teflon felt 113. As the pressing member 64a of the layer thickness regulating blade 64,
When urethane rubber or the like that is hard to be scraped is used, the front blade side seal 112 is omitted, and the leaf spring 64 is directly used.
A configuration may be adopted in which the Teflon felt 113 rides on “b”.

In the above description, the developer leakage preventing member at both ends is constituted by the side seal 104 of the base material, the intermediate layer film 109 and the Teflon felt 113 of the rubbing portion. The configuration is not limited to this. For example, the Teflon felt 113 is omitted, and the sponge side seal is extended to extend the leaf spring 6.
4b, the front blade side seal 112
May be configured so as to cover. Even in the case of such a configuration, the sponge-to-sponge contact portions are formed on both end sides of the pressing member 64a, and toner leakage can be reliably prevented.

In the above description, the developing device 5
0 has been described as an example in which the drum cartridge 2a is detachably attached to the image forming apparatus main body. However, the present invention is not limited to this. The drum cartridge 2a and the developing device 50 may be detachably attached to the apparatus main body, and may be detachably attached to the image forming apparatus by a process cartridge (the process cartridge of claim 9) in which the drum cartridge 2a and the developing device 50 are formed in an integrated housing. It may be configured. Further, the developing device 50 does not necessarily need to be detachable from the image forming apparatus, and may be a stationary type. If the present invention is applied to a developing device cartridge or a process cartridge, there is an effect that toner leakage at the time of attachment / detachment can be surely prevented. The effect of not contaminating can be exerted.

Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. Can easily be inferred.

[0090]

According to the first aspect of the present invention, there is provided a leaf spring member formed to extend in the longitudinal direction of the developer carrier.
A pressing member made of rubber or resin integrally formed with the leaf spring member and extending in a longitudinal direction of the developer carrier, and pressing the peripheral surface of the developer carrier by the pressing member to A developer layer thickness regulating member that forms a thin layer of, a base member that is made of at least a foamed elastic body, and is attached to the developing device housing near both longitudinal ends of the developing device housing opening;
A developer slidable portion attached to the base portion and rubbing against the peripheral surfaces of both ends of the developer carrier. The length of the leaf spring member in the longitudinal direction is longer than the length of the pressing member in the longitudinal direction, and the pressing member is formed at both ends in the longitudinal direction of the leaf spring member with exposed portions of the surface of the leaf spring member. And the rubbing portions of the developer leakage preventing members at both ends are formed so as to extend so as to cover the exposed portions of the leaf spring members, and are adhered and attached to the exposed portions. The developer can be prevented from entering the side end surface of the pressing member from the back side of the pressing member, and toner leakage from the side end surface of the pressing member can be reliably prevented. Part of the rubbing portion does not enter between the pressing member and the developer carrying member to form a gap, so that it is possible to reliably prevent toner leakage due to such a gap. The movement of the leaf spring member of the developer layer thickness regulating member is not hindered by the developer leakage prevention members at both ends, and the pressing of the pressing member against the developer carrier is uniformly performed in the longitudinal direction of the developer carrier. Can be kept. As a result, a favorable developing operation can be performed.

According to the second aspect of the present invention, the leaf spring member is formed to extend in the longitudinal direction of the developer carrier, and is formed integrally with the leaf spring member to extend in the longitudinal direction of the developer carrier. A developer or a pressing member made of rubber or resin, and a pressing member pressed against the peripheral surface of the developer carrier to form a thin layer of developer, and a developing device housing. And a developer leakage prevention member attached to the developing device housing near both ends in the longitudinal direction of the opening and rubbing against the peripheral surfaces of both ends of the developer carrying member. The regulating member, the longitudinal length of the leaf spring member is longer than the longitudinal length of the pressing member, the pressing member,
At the both ends in the longitudinal direction of the leaf spring member, provided at positions where exposed portions of the surface of the leaf spring member are formed, a foamed elastic material layer is adhesively attached to the exposed portion, and the developer leakage preventing members at both ends are further provided. Is formed so as to cover the foamed elastic material layer and is adhered and attached to the foamed elastic material layer, so that intrusion of the developer from the back side of the leaf spring member to the side end face side of the pressing member is suppressed, and the pressing is performed. It is possible to reliably prevent toner from leaking from the side end surface of the member. Further, it is possible to reliably prevent the developer from leaking between the foamed elastic material layer and the developer leak preventing members at both ends. Further, the movement of the leaf spring member of the developer layer thickness regulating member is not hindered by the developer leakage preventing members at both ends, and the amount of collapse of the foamed elastic layer increases even when the pressing member is worn, so that the pressing force increases. Since the pressing force of the member against the developer carrier is not changed, the pressing of the pressing member against the developer carrier can be kept uniform in the longitudinal direction of the developer carrier, and a good developing operation can be performed. it can.

According to the third aspect of the present invention, the side end surfaces of the pressing member and the side end surfaces of the developer leakage preventing members at both ends are places where they are rubbed with each other without being adhered and attached. However, the length of the contact portion on both side end surfaces is 4 mm
With the above setting, it is possible to reliably prevent the developer from leaking from the contact portion.

According to the fourth aspect of the present invention, the side end surfaces of the pressing member and the side end surfaces of the developer leakage preventing member and the foamed elastic layer at both ends are not attached to each other but are attached to each other. It is a place to be rubbed, but by setting the length of the contact portion on each side end surface to 4 mm or more,
Leakage of the developer from the contact portion can be reliably prevented.

According to the developing device of the fifth aspect, since the pressing member is formed of silicone rubber, good chargeability can be maintained, and the developer can be appropriately frictionally charged. Moreover, as described above, if the developer leakage preventing members at both ends can secure a certain amount of collapse,
Even when the silicone rubber is worn by long-term use, the pressure change of the developer layer thickness regulating member against the developer carrier can be reliably prevented. Therefore, the developer layer thickness can be uniformly maintained in the longitudinal direction of the developer carrying member while reliably preventing the developer from leaking, and a good developing operation can be performed.

According to the developing device of the sixth aspect, since a conductive member is used as the pressing member, a predetermined voltage is applied between the pressing member and the developer carrier,
Injection of charge into the developer or prevention of the developer of the opposite polarity from passing through the pressure contact portion between the pressing member and the developer carrier can be prevented, thereby reducing the occurrence of print fog. In addition, since the developer is always present in the pressure contact portion between the pressing member and the developer carrier over the entire region in the longitudinal direction of the developer carrier, even when a voltage is applied to the pressing member, the developer is It is possible to prevent a current from flowing directly to the developer carrier.

According to the developing device of the present invention, since the polymerized toner produced by the polymerization method is used as the developer, the developing operation with high fluidity and high definition can be performed. However, this polymerized toner is liable to cause toner leakage due to its high fluidity. However, as described above, toner leakage from both ends of the developer layer thickness regulating member can be reliably prevented.

According to the developing device of the present invention, since a roller made of a conductive elastic material is used as the developer carrying member, a part of the developer leaking member at both ends is partially covered with the developer layer. When entering between the thickness regulating member and the developer carrying member, the developer is likely to leak due to damage to the surface of the developer carrying member. Since the layer thickness regulating member is provided on both side end surfaces of the pressing member, there is no such penetration between the developer layer thickness regulating member and the developer carrier, so that the surface of the developer carrier is damaged. Developer can be reliably prevented.

According to the ninth aspect of the present invention, the process cartridge detachably formed in the image forming apparatus is provided with the developing device according to any one of the first to eighth aspects. Even when the cartridge is attached or detached, the developer can be reliably prevented from leaking. Further, depending on the developer leakage preventing members at both ends, the pressing of the developer layer thickness regulating member against the developer carrier does not change in the longitudinal direction of the developer carrier, so that a good developing operation can be performed. .

According to the tenth aspect of the present invention, the developing device according to any one of the first to eighth aspects is formed detachably with respect to the image forming apparatus or the process cartridge. Also, it is possible to reliably prevent the developer from leaking even when attaching or detaching. Further, depending on the developer leakage preventing members at both ends, the pressing of the developer layer thickness regulating member against the developer carrier does not change in the longitudinal direction of the developer carrier, so that a good developing operation can be performed. .

According to the image forming apparatus of the eleventh aspect,
Since the developing device according to any one of claims 1 to 8, the process cartridge according to claim 9, or the developing device cartridge according to claim 10 is provided, the developer does not leak and the inside of the image forming apparatus main body is not generated. Developer contamination can be reliably prevented. Further, depending on the developer leakage preventing members at both ends, the pressing of the developer layer thickness regulating member against the developer carrier does not change in the longitudinal direction of the developer carrier, so that a good image forming operation can be performed. it can.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention.

2 (A) is a partially cutaway perspective view showing a seal portion of a developing device case before a seal member is attached, and FIG. 2 (B) is the seal seen from the direction of arrow B shown in FIG. 2 (A). It is a figure which shows a part.

3 (A) is a partially cutaway perspective view showing a seal portion of a developing device case when a side edge seal is attached, and FIG. 3 (B) is a cross-sectional view taken along line CC of FIG. 3 (A). , FIG.
FIG. 4C is a view showing the seal portion viewed from the direction of arrow B shown in FIG.

4 (A) is a partially cutaway perspective view showing a seal portion of a developing device case when an upper side seal attaching film is attached, and FIG. 4 (B) is an arrow A shown in FIG. 4 (A); FIG. 4C is a view showing the seal portion viewed from the direction, and FIG.
It is a figure showing the seal part concerned seen from the arrow B direction shown to (A).

5A is a partially cutaway perspective view showing a seal portion of a developing device case when a side seal is attached, FIG.
FIG. 5B is a diagram showing the seal portion as viewed from the direction of arrow B shown in FIG.

FIG. 6A is a partially broken perspective view showing a seal portion of a developing device case when a lower side seal is attached,
FIG. 6B is a diagram showing the seal portion as viewed from the direction of arrow B shown in FIG. 6A.

7A is a partially cutaway perspective view showing a seal portion of a developing device case when an edge seal is attached, FIG.
FIG. 8B is a diagram showing the seal portion as viewed from the direction of arrow B shown in FIG.

FIG. 8A is a partially broken perspective view showing a seal portion of a developing device case when an upper side seal is attached;
FIG. 8B is a diagram showing the seal portion viewed from the direction of arrow A shown in FIG. 8A, and FIG. 8C is a diagram showing the seal portion viewed from the direction of arrow B shown in FIG. It is.

FIG. 9 is a front view showing a seal portion of the developing device case when an upper seal is attached.

FIG. 10 is a view showing a seal portion viewed from the direction of arrow B shown in FIG. 9;

11 (A) is a partially cutaway perspective view showing a seal portion of a developing device case when an intermediate layer film is attached, and FIG. 11 (B) is viewed from an arrow B direction shown in FIG. 11 (A). FIG. 3 is a diagram showing the seal portion.

FIG. 12 is a partially cutaway perspective view showing a seal portion of the developing device case when a side edge seal is attached.

13 (A) is a diagram of the layer thickness regulating blade viewed from the back side, FIG. 13 (B) is a diagram of the layer thickness regulating blade viewed from the front side, and FIG. 13 (C) is a diagram of FIG. 11 (B). It is a figure showing the seal part seen from the arrow B direction similarly.

14A is a partially cutaway perspective view showing a seal portion of a developing device case when Teflon felt is attached, and FIG. 14B is viewed from the direction of arrow A shown in FIG. 14A. FIG. 14C is a diagram showing the seal portion, and FIG. 14C is a diagram showing the seal portion viewed from the direction of arrow B shown in FIG.
FIG. 14D is a sectional view taken along line DD of FIG.

FIG. 15A is a plan view showing a lower film and the vicinity of a mounting portion thereof, and FIG. 15B is a diagram showing an adhesive surface of the lower film.

16 (A) is a partially cutaway perspective view showing a seal portion of a case 51 on the opposite side to FIG. 14 (A) when a lower film is attached, and FIG. 16 (B) is FIG. 14 (C). FIG. 7 is a view showing the seal portion as viewed from the direction of arrow B as in FIG.

FIG. 17 is a diagram showing the shape of the side end surface of the pressing member 64a shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser beam printer 50 Developing device 51 Case 52 Toner accommodating chamber 59 Developing roller 64 Layer thickness regulating blade 64a Pressing member 64b Leaf spring 64d Contact portion 100 Side seal mounting area 101 Lower seal mounting area 102 Side edge seal 103 Upper side seal 103 Attachment film 104 Side seal 105 Lower side seal 106 Edge seal 107 Upper side seal 108 Upper seal 109 Intermediate layer film 109a Cut portion 110 Side edge seal 111 Back side blade side seal 112 Front side blade side seal / 113 Teflon felt 114 Lower film

Claims (11)

[Claims] A developer carrier is rotatably disposed in an opening of a developing device housing for accommodating a developer, and a thin layer of the developer formed on the developer carrier is formed into an electrostatic latent image. What is claimed is: 1. A developing device which forms a visible image by facing each other, comprising: a leaf spring member formed extending in a longitudinal direction of said developer carrier; and a leaf spring member extending in a longitudinal direction of said developer carrier. And a pressing member made of rubber or resin integrally formed with the pressing member. The pressing member is provided so as to press against the peripheral surface of the developer carrying member, and a developer layer thickness regulation for forming a thin layer of the developer is provided. A member, which is made of at least a foamed elastic body, and is attached to the developing device housing near both ends in the longitudinal direction of the opening of the developing device housing; and the developer carrier mounted on the base material portion And a rubbing portion that rubs against the peripheral surfaces on both ends of the developer. The developer layer thickness regulating member, wherein the length of the leaf spring member in the longitudinal direction is longer than the length of the pressing member in the longitudinal direction, and the pressing member is a longitudinal member of the leaf spring member. At both ends in the direction to form exposed portions of the surface of the leaf spring member, and the rubbing portions of the developer leakage preventing members at both ends cover the exposed portions of the leaf spring member. A developing device, which is formed so as to extend and is adhesively attached to the exposed portion. 2. A developer carrier is rotatably disposed at an opening of a developing device housing for accommodating a developer, and a thin layer of the developer formed on the developer carrier is formed into an electrostatic latent image. What is claimed is: 1. A developing device which forms a visible image by facing each other, comprising: a leaf spring member formed extending in a longitudinal direction of said developer carrier; and a leaf spring member extending in a longitudinal direction of said developer carrier. And a pressing member made of rubber or resin integrally formed with the pressing member. The pressing member is provided so as to press against the peripheral surface of the developer carrying member, and a developer layer thickness regulation for forming a thin layer of the developer is provided. A member, both ends of which are attached to the developing device housing in the vicinity of both ends in the longitudinal direction of the opening of the developing device housing, and rub against the peripheral surfaces of both ends of the developer carrying member; The developer layer thickness regulating member has a length in the longitudinal direction of the leaf spring member, The pressing member is longer than the longitudinal length of the pressing member, and the pressing member is provided at a position forming an exposed portion of the surface of the leaf spring member at both ends in the longitudinal direction of the leaf spring member. Has an elastic foam layer bonded and attached, and the developer leakage preventing members at both ends are formed to extend so as to cover the elastic foam layer, and are adhesively attached to the elastic foam layer. A developing device. 3. The developing device according to claim 1, wherein a length of a contact portion between the pressing member and the developer leakage preventing member at both ends is set to 4 mm or more. 4. The pressing member has a length of 4 m in contact with the developer leakage preventing member at both ends and the foamed elastic material layer.
3. The developing device according to claim 2, wherein m is set to m or more. 5. The developing device according to claim 1, wherein said pressing member is formed of silicone rubber. 6. The developing device according to claim 1, wherein the pressing member has conductivity. 7. The developing device according to claim 1, wherein said developer is a polymerized toner produced by a polymerization method. 8. The apparatus according to claim 1, wherein the developer carrier is a roller formed of a conductive elastic body.
8. The developing device according to any one of items 7 to 7. 9. A process cartridge detachably formed in an image forming apparatus, comprising: a carrier for the electrostatic latent image; and a developing device according to claim 1. A process cartridge characterized by the above-mentioned. 10. A developing device cartridge, wherein the developing device according to claim 1 is detachably mounted on an image forming apparatus or a process cartridge. 11. An image forming apparatus comprising the developing device according to claim 1, a process cartridge according to claim 9, or a developing device cartridge according to claim 10.