JPH06124040A - Image forming unit - Google Patents

Abstract

PURPOSE:To improve the operability of the cleaning and exchange of a toner replenishing roller and a thin layer forming blade provided inside a developing unit. CONSTITUTION:A pair of side plates of the developing unit are composed of a pair of replenishing unit side plates 20 and a pair of developing/stirring unit side plates 30 as separated bodies, which are separated in the vicinities of both sides in the width directions of a thin layer forming blade 10 and a blade holder 14 and overlapped on both sides in the axial direction of a toner replenishing roller 3 and have bearing attaching holes on the overlapped parts of both sides, respectively. The side wall of a toner housing room is composed of a pair of the replenishing unit side plates 20 to hold respective members 3, 14, 11, etc., in the toner housing room. The side wall of a developing/stirring room is composed of a pair of the developing/stirring unit side plates 30 to hold respective members 2, 8, 18, etc., in the developing/stirring room. The shaft part of the toner replenishing roller 3 is held via the bearing capable of being removed on the overlapped parts of both pairs of the side plates 20 and 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming unit employed in an image forming apparatus such as a copying machine, a facsimile, a printer, etc., for example, a developing device and a cleaning device, and more specifically, it is disposed facing a developing roller. The present invention relates to an image forming unit capable of improving workability in cleaning and replacing a toner supply roller and the like.

[0002]

2. Description of the Related Art In this type of image forming unit, it is necessary to clean and replace built-in parts. For example, in a developing device that forms a thin layer of toner as a developer on a roller by contact with a blade or the like, changes in surface properties such as surface roughness due to abrasion of the roller surface, toner filming on the roller surface, and roller As the surface material, for example, rubber deteriorates, the toner thin layer ability of the roller itself deteriorates over time, and therefore the roller needs to be cleaned and replaced. In addition, since the toner adheres to the blade with time and the toner thin layer ability is lowered, cleaning and replacement are required.

[0003]

When a member such as a roller or a blade that needs to be cleaned or replaced is attached near the unit opening facing the image carrier such as the photoconductor, the cleaning or replacement is required. Although the work is relatively easy, if such a member is mounted inside the unit away from the unit opening, the cleaning or replacement work becomes difficult. For example, in the developing unit 1 shown in FIG. 2, a developing roller 2 with a built-in magnet is arranged so that a part of the developing roller 2 is exposed from the opening toward the photosensitive drum. Inside the unit, a toner replenishing roller 3, upper and lower conveying rollers 4, 5, upper and lower conveying screws 6, 7 and a developing doctor 8 also serving as a left side wall of the unit 1 are arranged so as to face the developing roller 2. It is set up. Further, the replenishment sponge roller 9 is brought into contact with the surface of the toner replenishment roller 3.
Further, a thinning blade 10 is provided, and an agitator 11 and a toner conveying screw 12 are provided above the supply sponge roller 9.

Here, in the developing unit 1, a lower end is attached to a peripheral wall of the unit and an upper end is in contact with the toner replenishing roller 3 at a predetermined pressure, a replenishing roller seal 13, the toner replenishing roller 3, and the thinning blade 10. And a blade holder 1 in which the upper part of the thinning blade 10 is attached to the lower end and the upper end is attached to the peripheral wall of the unit.
The developing roller 2 is formed by a partition wall 4
And the like, and is divided into a developing agitating chamber in which the agitator 11 and the like are disposed. Then, in the toner storage chamber, the upper toner transport screw 12
The toner sent from a toner tank (not shown) via the toner storage chamber is stored in the developing agitation chamber. The developer and the toner are replenished from the toner storage chamber via the toner replenishing roller 3. Is housed. In the figure, reference numeral 16 is a right casing forming the right side surface of the toner storage chamber, reference numeral 17 is an upper cover forming the upper surface of the storage chamber, and reference numeral 18 is developer replenishment forming the upper surface of the developing stirring chamber. The port cover, reference numeral 19 denotes a developing casing that constitutes the lower surface of the developing stirring chamber.

In such a developing unit 1, the toner replenishing roller 3 and the thinning blade 10 also need to be cleaned or replaced by fixing toner. However, since these are located inside the developing unit 1 away from the opening, cleaning and replacement are difficult, and moreover, they also function as partition walls for partitioning the toner storage chamber as described above. At the time of cleaning and replacement, the toner in the toner storage chamber and the two-component developer in the development agitation chamber may be mixed.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an image forming unit capable of improving workability of cleaning and replacement of built-in parts. .

[0007]

In order to achieve the above-mentioned object, the invention of claim 1 is an image forming unit having a rotating body therein which requires cleaning or replacement. Consist of a first side plate pair and a second side plate pair which are separate from each other and overlap each other in the axial direction of the rotating body, and have holes for bearing mounting respectively formed in the overlapping portions on both sides. Then, both shaft portions of the rotating body are held by the first side plate pair through a bearing removably attached to the shaft portion whose outer peripheral surface fits into the bearing mounting hole of the first side plate pair. At the same time, the outer peripheral surface is held by the second side plate pair via a bearing removably attached to the shaft portion that fits into the bearing mounting hole of the second side plate pair.

According to a second aspect of the present invention, in an image forming unit having a rotating body which needs cleaning or replacement inside, the side plate pairs of the unit overlap each other on both sides in the axial direction of the rotating body. And a first side plate pair and a second side plate pair that are separate from each other and have holes for mounting bearings formed in the overlapping portions on both sides, and both shaft portions of the rotating body are In the shaft portion, which fits into a hole for shaft attachment in one side plate pair of the side plate pair and the second side plate pair and penetrates the hole, and also fits in a hole for shaft attachment in the other side plate pair. It is characterized in that it is held by the first side plate and the second side plate via a bearing that is detachably attached.

According to a third aspect of the present invention, in the image forming unit according to the first or second aspect, which contains a member to which a bias is applied and a developer, the one of the first side plate pair and the second side plate pair is the above. A bearing housing having an end face portion that substantially covers an end face of the bearing inside the unit is attached to the hole for attaching the bearing in the pair of side plates positioned relatively inward in the axial direction of the rotating body, and the hole is formed in the hole of the bearing housing. It is characterized by fitting a bearing.

According to a fourth aspect of the present invention, there is provided a rotating body which requires cleaning or replacement, and an abutting member which abuts a peripheral surface of the rotating body in an axial direction of the rotating body. In the image forming unit using the contact member and the side plate as a part of the wall forming the developer accommodating portion, the side plate pair of the unit is divided in the vicinity of both sides in the width direction of the rotating body. It is composed of a first side plate pair that constitutes both side surface portions of the developer accommodating portion and a second side plate pair that constitutes the other unit side surface portion, and holds the rotating body and the corresponding contact member in the first side plate pair. It is characterized by that.

According to a fifth aspect of the present invention, both shaft portions of the rotating body are fitted into at least the first side plate pair and into bearing mounting holes formed in the first side plate pair. The image forming unit according to claim 4, wherein the bearing is detachably attached to the rotary body, and the displacement amount of the shaft portion in the direction perpendicular to the axis line when the bearing is removed is the rotation body and the rotary body. The present invention is characterized in that a regulating portion for regulating the position of the shaft portion is provided so that the contact state with the contact member falls within a range where the contact member is not released.

According to a sixth aspect of the present invention, there is provided a plate-shaped member that needs cleaning or replacement inside, and the plate-shaped member and the side plate are used as a part of a wall forming the developer accommodating portion for image formation. In the unit, a pair of side plates of the unit is divided in the vicinity of both sides in the width direction of the plate-shaped member, and a first side plate pair that constitutes both side surfaces of the developer accommodating portion, and the other side surface portion of the unit. And a second pair of side plates constituting the above, and the plate-shaped member is detachably held by the first pair of side plates.

[0013]

According to the first aspect of the invention, when cleaning or replacing the internal rotating body, the side plate pair of the first side plate pair and the second side plate pair, which is relatively outside at the overlap portion, is used. Both the bearings fitted in the bearing mounting holes in the above are removed from the shaft portion of the rotating body and the bearing mounting holes. As a result, the unit can be separated into two while the rotating body is held by the side plate pair located relatively inside at the overlapping portion. For example, if a notch portion having a width that allows the shaft portion of the rotating body to penetrate and that is open to the peripheral edge of the pair of side plates is formed in a row connected to the bearing mounting holes of the pair of side plates that are relatively outside, The unit can be separated into two by relatively separating the both side plates so that the shaft portion of the body passes through the cutout portion. At this time, the first side plate pair and the second side plate pair overlap each other on both sides in the axial direction of the rotary body, and bearing mounting holes are formed in the overlapping portions on both sides. Therefore, the rotating body is exposed between the pair of side plates while it is held.
Therefore, in this state, the peripheral surface of the rotating body can be cleaned. Then, when the rotating body is replaced or when it is necessary for cleaning, two bearings fitted into the bearing mounting holes in the side plate pair in which the rotating body is held are further provided. Both are removed from the shaft of the rotor and the hole for mounting the bearing. As a result, the rotating body can be removed from the pair of side plates. Here, after removing the rotary body as needed and installing a new rotary body,
The image forming unit can be reconfigured by mounting the bearings and assembling the pair of both side plates in the reverse order of the above.

According to a second aspect of the present invention, when cleaning or replacing the internal rotating body, the first side plate pair and the second side plate pair are fitted through the bearing mounting holes in the overlapping portions. Both bearings are removed from the shaft portion of the rotating body and the bearing mounting hole. As a result, the unit can be separated into two while the rotating body is gently held by the pair of side plates positioned relatively inward at the overlapping portion. For example, if a notch portion having a width that allows the shaft portion of the rotating body to penetrate and that is open to the peripheral edge of the pair of side plates is formed in a row connected to the bearing mounting holes of the pair of side plates that are relatively outside, The unit can be separated into two by relatively separating the both side plates so that the shaft portion of the body passes through the cutout portion. At this time, the first side plate pair and the second side plate pair overlap each other on both sides in the axial direction of the rotary body, and bearing mounting holes are formed in the overlapping portions on both sides. Therefore, the rotating body is exposed between the pair of side plates while it is held. Therefore, the peripheral surface of the rotating body can be cleaned in this state. When the rotating body is replaced or when cleaning is necessary,
The rotating body can be removed from the pair of side plates while the rotating body is held gently. Here, the image forming unit can be reconfigured by removing the rotating body and installing a new rotating body, if necessary, and then mounting the bearings and assembling the pair of both side plates in the reverse order of the above.

According to the third aspect of the invention, the end surface of the bearing inside the unit, which is fitted in the bearing mounting hole of the side plate pair located relatively inside, is substantially covered with a predetermined end surface portion of the bearing housing. This prevents the developer from coming into contact with the bearing. Further, when the unit is separated into two parts by the above-mentioned procedure, the end surface portion of the bearing housing comes into contact with a seal member such as an E ring attached to the shaft portion of the rotating body or a large diameter portion of the shaft. Thus, the sliding of the rotating body in the axial direction with respect to the relatively inner side plate pair is restricted.

According to a fourth aspect of the present invention, when cleaning or replacing the internal rotating body, after removing or adjusting a component for bringing the first side plate pair and the second side plate pair into a coupled state, the both side plates are removed. The pairs are separated, which separates the unit in two. At this time, the first side plate pair and the second side plate pair are
Since the rotor is divided near both sides in the width direction, the rotor is exposed between the pair of first side plates holding the rotor. Therefore, the peripheral surface of the rotating body can be cleaned in this state. Further, the first side plate pair that constitutes both side surfaces of the developer accommodating portion holds the rotating body and the abutting member that abuts against the rotating body, which constitutes a wall of the developer accommodating portion together with the side plate pair. So even if the unit is separated into two,
The developer container is maintained as it is on the first side plate side.

According to a fifth aspect of the present invention, in the image forming unit according to the fourth aspect, both shaft portions of the rotating body are mounted on at least the first side plate pair for mounting a bearing formed on the first side plate pair. It is held via a bearing that is removably attached to the shaft portion that fits into the hole. When cleaning or replacing the internal rotating body, after removing the bearing, which is one of the components for bringing the first side plate pair and the second side plate pair into the coupled state, the both side plate pairs are separated from each other. To separate the unit into two. At this time, as described above, the developer accommodating portion is maintained as it is on the side of the first side plate even when the unit is separated into two. Further, in the present invention, the displacement amount of the shaft portion in the direction perpendicular to the axis line when the bearing is removed by the regulating member is a range in which the contact state between the rotating body and the contact member is not released. Regulated to be inside.

According to the sixth aspect of the present invention, when cleaning or replacing the internal plate-shaped member, after removing or adjusting the parts for bringing the first side plate pair and the second side plate pair into the coupled state, both sides are removed. The plate pairs are separated, which separates the unit in two. At this time, the first side plate pair and the second side plate pair are
Since the plate-shaped member is divided near both sides in the width direction, the plate-shaped member is exposed between the pair of first side plates holding the plate-shaped member. Therefore, in this state, the exposed portion of the plate member can be cleaned. Further, since the first side plate pair that constitutes both side surface portions of the developer accommodating portion holds the plate-shaped member that constitutes the wall of the developer accommodating portion together with the side plate pair,
Even when the unit is separated into two parts, the plate-shaped member exposed between the pair of side plates becomes a part of the outer wall of the developer containing part, and the developer containing part is maintained as it is on the first side plate side. Then, when the plate-shaped member is replaced or when cleaning is necessary, the plate-shaped member exposed between the first side plates can be further removed. Here, after removing the plate-shaped member as necessary and attaching a new plate-shaped member, the image forming unit can be reconfigured by assembling the pair of both side plates in the reverse procedure to the above.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a developing unit of an electrophotographic copying machine (hereinafter referred to as copying machine) which is an image forming apparatus will be described below. First, the outline of the developing unit of this embodiment will be described. The built-in member of the developing unit of this embodiment is the same as that of the developing unit 1 shown in FIG. That is, the developing roller 2 with a built-in magnet is arranged so that a part thereof is exposed from the opening toward the photosensitive drum, and the toner replenishing roller 3, the upper and lower conveying rollers 4, 5 are arranged so as to face the developing roller 2. Vertical transport screw 6,
7 and a developing doctor 8 are provided. Further, a replenishing sponge roller 9 and a thinning blade 10 are arranged so as to be in contact with the surface of the toner replenishing roller 3, and an agitator 11 and a toner conveying screw 12 are arranged above the replenishing sponge roller 9. . Further, the inside of the developing unit 1 is partitioned into a developing stirring chamber and a toner accommodating chamber by a partition wall constituted by the replenishing roller seal 13, the toner replenishing roller 3, the thinning blade 10, and the blade holder 14. The toner is accommodated in the toner accommodating chamber, and the two-component developer (hereinafter referred to as developer) composed of the carrier and the toner is accommodated in the developing stirring chamber.

Here, as the material of the toner replenishing roller 3, a rubber material such as NBR (nitrile rubber) or silicon rubber, or a resin material such as fluororesin is used, and this rubber material or resin material is used in the entire roller. Instead, it may be provided only on the roller surface layer. Further, as the material of the toner supply roller 3, a metal roller such as aluminum or stainless steel can be used. As the material of the thinning blade 10, a thin plate metal such as carbon steel, a rubber material such as silicon rubber,
It is preferable to use a resin material such as a fluororesin, which has an appropriate elasticity. The replenishment sponge roller 9 may be formed by winding a metal cored bar on which foamed polyurethane is dispersed with carbon and subjected to a conductive treatment. When selecting materials for the toner replenishing roller 3, the replenishing sponge roller 9, and the thin layer blade 10, the toner charging polarity,
Alternatively, it is determined in consideration of the required charge amount and the like.

The upper and lower conveying rollers 4 and 5 are N,
A block magnet of S2 pole is built in and rotated counterclockwise so that the developer from the developing roller 2 is pumped up and conveyed. The upper conveying screw 6 rotates counterclockwise in the gutter-shaped screw casing 15,
The developer dropped from the peripheral surface of the upper conveying roller and received by the screw casing 15 is conveyed to the inner side of the developing device. An unillustrated developer dropping opening is formed in the lower lower portion of the screw casing 15, and an unillustrated overflow opening in the width direction is formed in the side wall opposite to the vertical transport rollers 4 and 5. . The lower conveying screw 7 rotates counterclockwise in the developer reservoir above the developing roller 2 and conveys the developer from the back side of the developing device to the front side.

The operation of the developing unit 1 will be described. The developing roller 2 rotates counterclockwise, and the electrostatic latent image on the photosensitive member 2 is developed and visualized by a bias voltage applied from a developing bias source (not shown). Image. Developing roller 2
The toner replenishing roller 3 arranged close to is rotated counterclockwise by turning on a toner replenishing clutch (not shown). The replenishing sponge roller 9, the thinning blade 10, and the replenishing roller seal 13 are pressed against the peripheral surface of the toner replenishing roller 3 and the entire area in the axial direction, so that the toner in the toner containing chamber rotates at the same time as the toner replenishing roller 3. The toner is rubbed against the toner replenishing roller 3 by the roller 9, conveyed along with the rotation of the toner replenishing roller 3, and continuously thinned on the toner replenishing roller 3 by the thinning blade 10. The toner thinned on the toner replenishing roller 3 is charged by a series of frictional actions, and is taken into contact with the developer magnetized and conveyed on the developing roller 2 by a contact and electrical action, and as a result, Increase the toner concentration in the developer.

The developer which has passed between the developing roller 2 and the toner replenishing roller 3 is located at a position facing the lower conveying roller 5.
All of the magnetic force of the lower conveyance roller 5 is pumped up to the lower conveyance roller 5. The developer drawn up by the lower carrying roller 5 is further drawn up by the upper carrying roller 4 and beyond the top of the carrying roller 4 to reach a location where there is no influence of the magnetic force on the screw casing 15 side. Thus, it falls by its own weight over the entire width and is received by the screw casing 15. Then, it is conveyed to the inner side of the developing device by the lower conveying screw in the screw casing 15 and falls from the developer dropping opening formed in the lower portion of the inner side of the screw casing 15. Also, this screw casing 15
A part of the developer received in step 6 also falls from the overflow opening. Then, the developer dropped from the developer dropping opening or the carver flow opening forms a developer pool above the developing roller 2 and is moved to the inner side of the developing device by the lower conveying screw 7 in the developer pool. Be transported. The developer thus sufficiently cross-mixed by the upper and lower conveying screws 6 and 7 is carried on the developing roller 2 by the magnetic force of the developing roller 2 and conveyed, and is regulated to a predetermined thickness by the developing doctor 8 on the way. After that, it is conveyed to a portion facing the photoconductor 2.

Next, in the main developing unit 1, a structure for improving workability of cleaning and replacing the toner replenishing roller 3 and the thin layer blade 10 which are built-in parts will be described. As described above, although the toner replenishing roller 3 and the thin layer blade 10 need to be cleaned and replaced, since they are located inside the developing unit 1 away from the opening, it is difficult to clean and replace them. Since they also function as partition walls that partition the developing chamber and the toner storage chamber, the toner in the toner storage chamber and the two-component developer in the developing agitation chamber may be mixed when cleaning and replacing them. is there. Therefore, in the present embodiment, in order to facilitate cleaning and replacement of the thinning blade 10 and the toner replenishing roller 3 located inside the part apart from the opening, they are held while being held between the pair of side plates. The side plate pair of the developing unit 1 is dividable into two pairs so that the side plate pair is exposed between the pair of side plates. Moreover, the side plate pair of the developing unit 1 can be divided into two pairs so that the toner storage chamber of the developing unit 1 is maintained as it is in a state where the side plate pair of the developing unit 1 is separated into two pairs.

The structure for this purpose will be described in detail below with reference to FIGS. 1 and 3A. FIG. 1 shows the developing unit 1.
Is an explanatory view of a state in which the replenishment unit side plate pair 20 and the development stirring unit side plate pair 30 which are two pairs of side plates are separated, and FIG. 3A is a sectional view showing an example of a support mechanism of the replenishment roller 3. .

In FIG. 1, the side plate pair of the developing unit 1 is divided near both sides of the thinning blade 10 and the blade holder 14 in the width direction and overlaps on both sides of the toner supply roller 3 in the axial direction ( The hatching 30a indicates an overlapping portion with respect to the developing stirring unit side plate pair 30), and a pair of replenishing unit side plate pairs 20 each having a bearing mounting hole formed in each of the overlapping portions on both sides. And a developing stirring unit side plate pair 30. Replenishing unit side plate pair 2
Reference numeral 0 forms a side wall of the toner storage chamber as a developer storage portion, and holds each member in the toner storage chamber. That is, the toner replenishing roller 3, the blade holder 14, the agitator 11 and the like are detachably attached, and the right casing 16 and the upper cover 17 to which the replenishing roller seal 13 is attached are also detachably attached. Here, the replenishing unit side plate pair 20, the toner replenishing roller 3,
A replenishing roller seal 13, which is in axial contact with the peripheral surface of the toner replenishing roller 3, a right casing 16, an upper cover 17, a blade holder 14, and a thinning blade 10.
This constitutes the wall of the toner storage chamber. The toner replenishing roller 3 is supported by the replenishing unit side plate pair 20 and the developing agitating unit side plate pair 3 as described later.
It is also bearing 0. The developing stirring unit side plate pair 3
0 constitutes a side wall of the developing and stirring chamber and holds each member in the developing and stirring chamber. That is, the developing roller 2, the carrying rollers 4, 5, the carrying screws 6, 7, the screw casing 15, the developing doctor 8, the developer replenishing port cover 1
8 and the developing casing 19 are removably attached. In addition, a bearing mounting hole 31 for mounting a bearing 32 (see FIG. 3A) for supporting both shaft portions of the toner replenishing roller 3 described later is formed in the overlap portion, and further, this bearing is provided. A notch portion 31a is formed in a row that is continuous with the mounting hole 31 and has a width that allows the shaft portion 3a of the toner replenishing roller 3 to penetrate therethrough and opens at the peripheral edge of the pair of side plates 30. The replenishing port cover 18 has a function of pressing when the replenishing unit side plate pair 20 and the developing and stirring unit side plate pair 30 are coupled.

An example of a supporting mechanism for supporting the toner replenishing roller 3 on the replenishing unit side plate pair 20 and the developing agitating unit side plate pair 30 will be described with reference to FIG. FIG. 3A is a cross-sectional view of the developing unit 1 adopting the same support mechanism, taken along a plane along the line XX in FIG. In this support mechanism, both shaft portions 3a of the toner replenishing roller 3 are detachably attached to the shaft portion 3a whose outer peripheral surface fits into the bearing mounting hole of the replenishing unit side plate pair 20. The outer peripheral surface of the replenishing unit side plate pair 20 is held, and the outer peripheral surface of the developing and stirring unit side plate pair 30 has a hole 31 for mounting a bearing.
It is held by the pair of side plates 30 of the developing and stirring unit via a bearing 32 which is detachably attached to the shaft portion 3a fitted to. In FIG. 3A, reference numeral 22 denotes a large diameter portion 23 of the shaft portion 3a of the toner replenishing roller 3 in the developing unit.
Is a ring seal mounted on the shaft portion 3a so as to be interposed between the end surface of the shaft and the inner surface of the pair of replenishing unit side plates 20, and the ring reel 22 prevents toner from entering the bearing 21. . Further, in FIG. 3A, reference numeral 33 is a magnet roller built in the developing roller 2, and this magnet roller 33 is the magnet roller shaft 3.
3a, the developing agitator unit side plate pair 30 is supported and positioned via the adjuster 34. Further, the developing roller 2 is
It is supported and positioned by a developing roller bearing 35 press-fitted into the developing stirring unit side plate pair 30, and is rotationally driven by a gear (not shown).

In the above construction, when cleaning or replacing the toner replenishing roller 3 and the thinning blade 10 inside, a component for connecting the replenishing unit side plate pair 20 and the developing stirring unit side plate pair 30 to each other. The bearing 3 for the toner replenishing roller 3 attached to the developing agitating unit side plate pair 30, which is also a component for removing the replenishing port cover 18 and also for bringing the pair of side plates 20, 30 into a coupled state.
Remove both two. Then, the pair of side plates of the supply unit
With the toner replenishing roller 3 held at 0, both side plate pairs 20 and 30 are so arranged that both shaft portions 3a of the toner replenishing roller 3 pass through the notch 31a connected to the bearing hole 31 of the developing stirring unit side plate pair 30. The developing unit 1 is separated and separated into a replenishing unit and a developing stirring unit.

Since the replenishing unit side plate pair 20 and the developing and stirring unit side plate pair 30 are divided in the vicinity of both sides of the thinning blade 10 in the width direction, the thinning blade 10 and toner replenishment. The rollers 3 are exposed between the pair of side plates while they are held. In this state, the peripheral surface of the toner supply roller 3 and the exposed portion of the thin layer blade 10 can be cleaned. Further, on the pair of replenishing unit side plates 20 forming both side surfaces of the toner accommodating chamber, the toner replenishing roller 3, which constitutes the wall of the toner accommodating chamber together with the pair of side plates, the replenishing roller seal 13 contacting the toner replenishing roller 3, and the thin roller Since the layering blade 10 is held, even when the developing unit 1 is separated into two, the layering blade 10 and the like exposed between the pair of side plates 20 become a part of the outer wall of the toner storage chamber. The toner storage chamber is maintained as it is on the side of the replenishment unit side plate pair 20. For example, the contact state between the toner replenishing roller 3 and the thinning blade 10 or the replenishing roller seal 13 is maintained as it is. Therefore, it is possible to prevent the toner from leaking from between these portions at the start of separation and mixing in the developing agitation unit, or the toner from leaking from between these portions to be scattered around during the separation. In addition, both side plates 20,
In the joined state of 30, the toner replenishing roller 3, the replenishing roller seal 13 abutting against the toner replenishing roller 3, and the thinning blade 10 which form a partition wall of the toner accommodating chamber and the developing stirring chamber As the outer wall of the room,
Since the developing unit 1 is used as it is, it is not necessary to provide another member for the outer wall of the toner storage chamber in the separated state, so that the developing unit 1 can be downsized.

When the thinning blade 10 needs to be replaced or needs to be cleaned, a replenishment unit is placed on the floor with the right casing 16 down, as shown in FIG. In the laid state, the thinning blade 10 can be removed together with the blade holder 14 exposed between the replenishing unit side plate pair 20. Even when the thinning blade 10 is removed in this way, the opening of the replenishing unit caused by this removal faces upward as shown in FIG. 4, so that toner leakage to the surroundings can also be prevented. Also,
When the toner replenishing roller 3 needs to be replaced or needs to be cleaned, the toner replenishing roller 3 is fitted in a bearing mounting hole in the replenishing unit side plate pair 20 which is still held. Both of the bearings 21 are removed from the shaft portion 3a of the toner replenishing roller 3 and the bearing mounting hole. As a result, the toner supply roller 3 can be removed from the side plate pair 20.

After the toner replenishing roller 3 and the thin layer blade 10 are cleaned and replaced, the bearings 21 and 32 are mounted and the pair of side plates 20 and 30 are assembled in the reverse order of the above. The developing unit 1 can be reconfigured. Here, the toner adhesion amount and the toner charge amount of the toner thin layer formed on the toner replenishing roller 3 may be varied.
The positional accuracy of the toner replenishing roller 3, the replenishing sponge roller 9 and the thin layer blade 10 is the same as those of the side plate pair 2 having the same position.
Since it is held at 0, it is accurately maintained even after the pair of both side plates 20, 30 are rejoined. Also, the developing roller 2
The gap accuracy between the developing roller 2 and the toner replenishing roller 3, which causes the variation in the amount of toner supplied to the upper developer, is also determined by the developing agitating unit side plate pair 30 that supports and positions the developing roller 2 by the toner replenishing roller 3. Is also supported and positioned via the bearing 32, so that both side plate pairs 2
Precisely maintained even after 0,30 recombination. That is, it is possible to configure the developing unit 1 that can be separated so that the toner replenishing roller 3 and the thinning blade 10 are exposed to the outside while maintaining these precisions.

Next, another example of a supporting mechanism for supporting the toner replenishing roller 3 on the replenishing unit side plate pair 20 and the developing and stirring unit side plate pair 30 will be described with reference to FIG. 3B. In the supporting mechanism of this example, both shaft portions 3a of the toner replenishing roller 3 are fitted into the shaft mounting holes 31 in the developing stirring unit side plate pair 30, and the holes 3 are provided.
1, a pair of replenishing unit side plates 20 and a developing agitating unit side plate, through a bearing 40 which is detachably attached to the shaft portion 3a and which also penetrates through the shaft replenishing unit side plate pair 20. The pair 30 holds it. In the figure, the same members as those in the example shown in FIG. 3A are designated by the same reference numerals.

In the supporting mechanism of this example, when cleaning or replacing the toner replenishing roller 3 inside, the bearing mounting hole is penetrated in the overlapping portion of the replenishing unit side plate pair 20 and the developing stirring unit side plate pair 30. The two bearings 40 fitted together are removed from the shaft portion 3a of the toner replenishing roller 3 and the bearing mounting hole. As a result, the shaft portion 3a of the toner replenishing roller 3 is held while the toner replenishing roller 3 is gently held by the replenishing unit side plate pair 20.
The developing unit 1 can be separated into these two units by separating the replenishing unit and the developing agitating unit so as to pass through the notch 31a.

According to the support mechanism of this embodiment, the bearing 40
Of the supporting surface for the shaft portion 3a of the toner replenishing roller 3 is
Since the bearings are larger than the bearing surfaces of the two sets of bearings 21 and 22 in the above example, the play between the bearings and the shaft portion 3a can be made relatively small. Further, in the combined state, the weight of the replenishing unit is set to be equal to that of both shaft portions 3a of the toner replenishing roller 3.
Even when the developing agitator unit side plate pair 30 is configured to receive the replenishing unit side plate through the above, the weight of the replenishing unit can be received in a larger area than the bearing 32 in the above example.
Further, since the bearing 40 is supported by the pair of side plates 20 and 30, the twisting of the front and rear side plates, which is inevitably generated in each of the developing stirring unit and the replenishing unit, is corrected by fitting the outer peripheral surface of the bearing 40. Further, the bending stress applied to the shaft portion 3a of the toner replenishing roller 3 can be reduced.

Next, with reference to FIGS. 5A to 5C, still another supporting mechanism for supporting the toner replenishing roller 3 on the replenishing unit side plate pair 20 and the developing agitating unit side plate pair 30. An example will be described. In the support mechanism of this example, a bearing housing 50 having an end surface portion 50a that substantially covers the end surface of the bearing 51 inside the unit is attached to the hole for bearing installation in the replenishing unit side plate pair 20, and the hole is formed in the bearing housing 50. , The shaft portion 3 of the toner supply roller 3
The bearing 51 with respect to a is fitted. A hole through which both shaft portions 3a of the toner replenishing roller 3 penetrate is formed in the end surface portion 50a, and as shown in FIG.
Is larger than the diameter B of the shaft portion 3a penetrating therethrough, and the difference (A-B) in size of the diameter B of the shaft portion 3a is the axis line when the bearing 51 is removed from the bearing housing 50. Displacement C of the shaft 3a in the direction perpendicular to
(See (c)) is set so that the contact state between the toner replenishing roller 3 and the replenishing roller seal 13 or the thinning blade is within a range where the contact state is not released. That is,
The inner surface of the hole of the bearing housing 50 constitutes a restriction portion that restricts the position of the shaft portion 3a when the bearing 51 is removed.

In the support mechanism of this example, when the internal toner replenishing roller 3 is cleaned or replaced, a bearing mounting hole or a bearing is provided in the overlapping portion of the replenishing unit side plate pair 20 and the developing agitating unit side plate pair 30. Housing 5
Both of the bearings 51 which are fitted to penetrate 0 are removed from the shaft portion 3a of the toner replenishing roller 3 and the bearing mounting hole. As a result, the replenishing unit and the developing agitating unit are separated from each other so that the shaft portion 3a of the toner replenishing roller 3 passes through the cutout portion 31a while gently holding the toner replenishing roller 3 on the replenishing unit side plate pair 20. The developing unit 1 can be separated into these two units. When removing the toner supply roller 3,
Further, after removing the bearing housing 50 from the replenishing unit side plate pair 20, the toner replenishing roller 3 is removed.

According to the support mechanism of the present example, even when the bearing 51 is removed when the unit is separated into two in the above-described procedure, the end face portion of the bearing housing 50 has the toner replenishing roller 3 attached thereto. By abutting on the ring seal 22 attached to the shaft portion 3a, sliding of the toner replenishing roller 3 with respect to the replenishing unit side plate pair 20 in the axial direction is restricted. Therefore, the replenishing roller seal 13 and the thinning blade 10 that are in contact with the toner replenishing roller 3 are not turned up, and the toner leakage from the vicinity of the shaft portion 3a of the toner replenishing roller 3 can be prevented.

When the bearing 51 is removed in order to separate the developing unit 1 into the replenishing unit and the developing agitating unit, the replenishing roller 3 has its own weight and the thinning blade 1
As shown in FIG. 5C, the pressing force of 0 displaces in the direction perpendicular to the axis, but the shaft portion 3a moves to the bearing housing 5
The amount C of displacement of the toner replenishing roller 3 and the replenishing roller seal 13 and the thinning blade 10 is restricted so that the contact state due to the elasticity of the toner replenishing roller 3 and the replenishing roller seal 13 is not released. Therefore, even if the bearing 51 is removed, it is possible to prevent the toner from leaking between the toner replenishing roller 3 and the replenishing roller seal 13 or the thinning blade 10.

Even when the replenishing unit and the developing agitating unit are in the coupled state, the end face of the bearing 51 fitted in the bearing mounting hole of the replenishing unit side plate pair 20 inside the unit is fixed to the bearing housing 50. Since it is almost covered with the end surface portion 50a, it is possible to prevent the developer in the developing stirring chamber from coming into contact with the bearing 51. For this reason, there is no risk of bias leak through the developer, and a metal bearing having good wear resistance, such as sintered metal, can be used as the bearing 51. Further, it is possible to prevent toner from sticking and deterioration of the ring seal 22 due to oil from the bearing 51.

The bearing 51 in the example shown in FIG.
Similar to the example of (b), the developing agitating unit side plate pair 30 is fitted into the shaft mounting hole 31 and penetrates the hole 31,
Moreover, the one that fits also into the shaft mounting hole in the replenishing unit side plate pair 20 is used, but instead of this, as shown in FIG.
You may use two sets of bearings 21 and 32 like the example of (a). Although the developing unit as the image forming unit has been described above, the present invention can also be applied to a cleaning unit and the like.

[0041]

According to the first aspect of the present invention, when cleaning or replacing the internal rotating body, the rotating body is held by the pair of side plates located relatively inside at the overlap portion,
Since the unit can be separated into two parts and the rotor can be exposed between the pair of side plates holding the unit in this separated state, the workability of cleaning and replacement of the rotor can be improved.

According to the second aspect of the present invention, when cleaning or replacing the internal rotating body, the rotating body is gently held by the pair of side plates located relatively inside at the overlap portion, Since the unit can be separated into two parts and the rotor can be exposed between the pair of side plates holding the unit in this separated state, the workability of cleaning and replacement of the rotor can be improved. Further, in order to hold both shaft portions of the rotating body on the first side plate and the second side plate, the shaft fitting holes are fitted in the shaft mounting holes in one side plate pair of the first side plate pair and the second side plate pair. Since a bearing removably attached to the shaft portion that penetrates through and is also fitted into the shaft attachment hole in the other side plate pair is used, the support surface of the bearing for the shaft portion is This is larger than the supporting surface of each bearing when both shafts are held on both side plates by using two sets of bearings. Therefore, the play between the bearing and the shaft can be made relatively small, and the bending stress applied to the shaft can be made small. Therefore, the rotation of the rotating body can be made relatively smooth.

According to the third aspect of the invention, the end surface inside the unit of the bearing fitted in the bearing mounting hole of the side plate pair located relatively inside is substantially covered with the predetermined end surface portion of the bearing housing. Since the developer is prevented from coming into contact with the bearing, it is possible to prevent leakage through the bearing and the developer even when a bias is applied to the rotating body whose shaft portion is supported by the bearing. Therefore, it is possible to use a bearing made of metal such as sintered metal having good wear resistance. Also, when the unit is separated into two parts and the bearing fitted in the bearing mounting hole of the side plate pair located relatively inside is removed, the end face portion of the bearing housing is Since it abuts on a seal member such as a V-ring attached to the shaft portion of the shaft or a large diameter portion of the shaft to restrict the sliding of the rotating body in the axial direction with respect to the relatively inner side plate pair, the axial direction of the rotating body It is possible to prevent the developer from leaking between the shaft portion and the bearing mounting hole due to the sliding of the developer.

According to the fourth aspect of the present invention, when cleaning or replacing the internal rotating body, the unit can be separated into two while the rotating body is held by the first side plate pair, and this separation is performed. In this state, the rotating body can be exposed between the pair of side plates holding the rotating body, so that the workability of cleaning and replacing the rotating body can be improved. Further, the first side plate pair forming both side surfaces of the developer accommodating portion is caused to hold the rotating body and an abutting member that abuts against the rotating body, which constitutes a wall of the developer accommodating portion together with the side plate pair. As a result, even when the unit is separated into two, the developer accommodating portion is maintained as it is on the first side plate side, so that the developer can be prevented from leaking from the developer accommodating portion even when the unit is separated into two. .

According to the invention of claim 5, when the bearing is removed to separate the unit into two, the displacement amount of the shaft portion of the rotating body in the direction perpendicular to the axis is in contact with the rotating body. Since the regulation member regulates the contact state with the member within the range where it cannot be released, even when the bearing is removed, leakage of the developer from between the rotating body and the contact member is prevented. It can be prevented.

In the sixth aspect of the invention, when cleaning or replacing the internal plate-shaped member, the unit can be separated into two while the plate-shaped member is held by the first side plate pair, and Since the plate member can be exposed between the pair of first side plates in the separated state, it is possible to improve the workability of cleaning the exposed portion of the plate member and replacing the plate member. In addition, the first side plate pair that constitutes both side surfaces of the developer accommodating portion holds the plate-shaped member that constitutes the wall of the developer accommodating portion together with the pair of side plates, thereby separating the unit into two parts. However, since the plate-shaped member exposed between the pair of side plates becomes a part of the outer wall of the developer accommodating portion and the developer accommodating portion is maintained on the side of the first side plate as it is, the unit is separated into two. However, it is possible to prevent the developer from leaking from the developer container.

[Brief description of drawings]

FIG. 1 is an explanatory view of a state in which a developing unit 1 according to an embodiment is separated into a replenishing unit side plate pair 20 and a developing stirring unit side plate pair 30 which are two pairs of side plates.

FIG. 2 is a front view showing a schematic configuration in the developing unit 1.

FIG. 3A is a cross-sectional view of a supply roller 3 support mechanism according to an example. (B) is sectional drawing of the supply roller 3 support mechanism which concerns on another example.

FIG. 4 is an explanatory view showing a state in which the toner replenishing roller 3 and the blade holder 14 are removed from the replenishing unit side plate pair 20.

FIG. 5A is a sectional view of a supply roller 3 support mechanism according to still another example. (B) is a partially enlarged view of the support mechanism. (C)
3 is a partially enlarged view of the replenishing unit in which the developing unit 1 employing the same supporting mechanism is separated into a developing stirring unit side plate pair 30 and a replenishing unit side plate pair 20. FIG.

[Explanation of symbols]

 1 Developing Unit 2 Developing Roller 3 Toner Replenishing Roller 3a Shaft 8 Developing Blade 10 Thinning Blade 11 Agitator 13 Replenishing Roller Seal 14 Blade Holder 18 Replenishment Port Cover 20 Replenishing Unit Side Plate Pair 22 Sealing Ring 30 Developing Stirring Unit Side Plate Pair 31 Bearing Mounting hole 31a Notch 21, 32, 40, 51 Bearing 50 Bearing housing 50a End surface

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Nojima 1-3-6 Nakamagome, Ota-ku, Tokyo Stock company Ricoh Co., Ltd. (72) Noboru Sawayama 1-3-6 Nakamagome, Ota-ku, Tokyo Shares Within Ricoh Company (72) Inventor Kaoru Yoshimatsu 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company (72) Inventor Katsuji Watanabe 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh (72) Inventor Takuji Yoneda 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd.

Claims (6)

[Claims] 1. An image forming unit having a rotating body inside which needs cleaning and replacement, wherein side plate pairs of the unit overlap on both sides in the axial direction of the rotating body and on both sides. The lap portion is formed with a pair of first side plates and a pair of second side plates, each of which has a hole for mounting a bearing formed therein, and both shaft portions of the rotating body have an outer peripheral surface having a pair of first side plates. The first side plate pair is held through a bearing that is detachably attached to the shaft part that fits into the bearing mounting hole, and the outer peripheral surface fits into the bearing mounting hole of the second side plate pair. An image forming unit, which is held by a second pair of side plates through a bearing detachably attached to the shaft portion. 2. An image forming unit having a rotating body inside which needs cleaning and replacement, wherein side plate pairs of the unit overlap each other on both sides in the axial direction of the rotating body and both sides overlap each other. The lap portion is formed with a pair of first side plates and a pair of second side plates, each of which has a hole for mounting a bearing, and both shaft portions of the rotating body are composed of a pair of first side plates and a pair of second side plates. A bearing removably attached to the shaft portion that fits into a hole for shaft attachment in one side plate pair and penetrates the hole, and also fits in a hole for shaft attachment in the other side plate pair An image forming unit, which is held by the first side plate and the second side plate via the. 3. The image forming unit according to claim 1, wherein a member to which a bias is applied and a developer are contained, and the first side plate pair and the second side plate pair are compared in the axial direction of the rotating body. A bearing housing having an end face portion that substantially covers the end face of the bearing inside the unit is attached to the hole for attaching the bearing in the pair of side plates located on the inner side, and the bearing is fitted into the hole of the bearing housing. The image forming unit according to claim 1 or 2. 4. A rotating body that needs to be cleaned or replaced, and an abutting member that abuts a peripheral surface of the rotating body in the axial direction of the rotating body. The rotating body, the corresponding contacting member, and a side plate are provided. In an image forming unit used as a part of a wall that constitutes a developer accommodating portion, both side surface portions of the developer accommodating portion, in which a pair of side plates of the unit is divided near both sides in the width direction of the rotating body. And a second side plate pair that constitutes the other side surface of the unit, and the rotating body and the corresponding contact member are held by the first side plate pair. Unit. 5. Both shafts of the rotating body are removably attached to at least the first side plate pair and to the shafts that fit into bearing mounting holes formed in the first side plate pair. The image forming unit according to claim 4, wherein the shaft is held by a bearing, and when the bearing is removed, the displacement amount of the shaft portion in the direction perpendicular to the axis is the contact between the rotating body and the contact member. 5. A restricting portion for restricting the position of the shaft portion is provided so that the state is within the range where the state is not released.
Image forming unit. 6. A unit for image formation, comprising a plate-shaped member which needs cleaning or replacement inside, and which uses the plate-shaped member and the side plate as a part of a wall forming a developer accommodating portion. A pair of first side plates, which are divided in the vicinity of both sides in the width direction of the plate-like member, and which constitute both side face portions of the developer accommodating portion, and a second side plate pair which constitutes the other side face portion of the unit. And a plate-shaped member that is detachably held by the first side plate pair.