JPH09269657A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device capable of more surely and stably preventing the developer leakage from a developing roll either end part by use of a sealing member, and easily performing fitting work and replacing work of the sealing member in addition thereto, and moreover, suiting to recycling. SOLUTION: As a sealing member 8 provided between the either end part of the developing roll 4 and a housing 2, this device adopts a member composed by combining slide-contacting elastic member 80 arranged on the side held in contact with either end part of the developing roll 4, and the holder member 81 provided with a curving surface shape for holding the slide-contacting elastic member 80 arranged on the side held in contact with the housing 2, while composed so as to be attached in freely attachably and detachably corresponding to the engaging part 20 of the adobe holder member 81 disposing on a region for fixing the developing roll end part of the housing 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a developing device provided with a seal member for preventing leakage of the developer between both ends of a developing roll and a housing.

[0002]

2. Description of the Related Art A developing device is usually provided with a developing roll that rotates in the state of being close to an electrostatic latent image bearing member such as a photoconductor, and the developer is carried by the developing roll to carry the electrostatic latent image bearing member. The electrostatic latent image formed on the electrostatic latent image carrier is visualized as it is conveyed to the developing area facing the body. Especially, both ends of the developing roll and the housing of the developing device are formed. Therefore, there is a problem that the developer leaks out from between the two areas. Therefore, it is necessary to take sufficient measures to prevent such developer leakage.

As a developing device which takes such measures, a device in which a soft elastic seal member such as felt, sponge, rubber or the like is attached between both ends of the developing roll and the housing (Japanese Patent Laid-Open No. 1-150179). ) Or a device having a seal member formed by molding a porous elastic body in the shape of a gap between both ends of the developing roll and the housing (Japanese Patent Laid-Open No. 3-2).
No. 29284) is known.

However, in any of these developing devices, the seal member is attached to the curved developing roller mounting portion of the housing by using a double-sided adhesive tape or adhesive, or by utilizing self-adhesiveness. Since the seal member is attached by attaching the seal member, there are problems that the workability of attaching the seal member is poor, and that the attaching accuracy varies. In particular, when the mounting accuracy is poor, a sufficient sealing effect may not be obtained.

Moreover, when the seal member is worn or deteriorated due to long-term use and the original seal effect cannot be obtained, the seal member needs to be replaced, but it is directly attached to the housing. The work of peeling off the seal member was complicated, and the work of installing a new seal member was also troublesome as described above.

Also in the technical field of developing devices, there is a tendency to positively use those that can be reused in response to the recent increase in the recycling movement, and the developing device is constructed by such an influence. It is also required that each of the parts to be installed be configured to be easily removable. From this point of view, it is not so desirable to directly attach and fix the above-mentioned seal member to the housing.

Further, in recent years, there have been many cases in which a developing device for a two-component developer is used in a copying machine or the like, which is increasing the copying speed. In the case of using the device, when the carrier particles composed of iron powder or the like constituting the two-component type developer enter between the seal member and the developing roll as described above, they are accumulated between them and the sealing effect of the seal member is obtained. May be deteriorated. When such a phenomenon occurs, the seal member may have to be replaced.

Further, in the case of such a two-component developing device, a developer regulating member is provided for regulating the amount of the developer when the magnetic brush is formed on the developing roll to convey the developer. However, since the developer regulating member needs to be accurately installed with a predetermined distance from the developing roll, there are the following problems.

That is, the developer regulating member may be detached and reattached when the seal member is replaced or the like in addition to being attached in the manufacturing process of the developing device. It was necessary to perform the complicated work of adjusting the interval of using a gap gauge (thickness gauge). Specifically, the gap gauge is sandwiched between the developing roll and the developer regulating member to adjust the fixing position of the developer regulating member. May scratch the surface. Also, the gap gauge may wear as the number of times of use increases and the gauge function may not be fulfilled.
It may have to be replaced on a regular basis.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned various problems of the prior art. The purpose of the present invention is to seal the developing roll from both ends by using seal members. Another object of the present invention is to provide a developing device which can prevent developer leakage more reliably and stably, can easily carry out an attaching work and a replacing work of the seal member, and is suitable for recycling.

Further, according to the present invention, when the developer regulating member is provided, the work of attaching the developer regulating member to the developing roll while ensuring a predetermined space can be performed more easily. It is also an object to provide a device.

[0012]

The developing device of the present invention is mounted on a housing of the developing device and an opening provided in the housing so as to rotate in the state of being close to the electrostatic latent image carrier, A developing roll that carries a developer and conveys the developer to a developing area facing the electrostatic latent image carrier, and a seal member that prevents developer leakage is provided between both ends of the developing roll and the housing. In the developing device, the seal member has a sliding contact elastic member arranged on the side in contact with the end of the developing roll, and a curved surface accommodating portion holding the sliding contact elastic member, and the side in contact with the housing. It is configured to be combined with the holder member arranged in the above, and is detachably attached to the fitting portion of the holder member provided at the portion where the developing roll end of the housing is attached. And it is characterized in that it is configured to.

It is desirable that the above-mentioned sheet member is constructed such that the sliding contact elastic member is detachably held in the curved surface accommodating portion of the holder member. In this case, it is desirable to further provide a protrusion for preventing the sliding contact elastic member from being displaced in the curved surface accommodating portion of the holder member.

When the developing device of the present invention is provided with a developer regulating member which is disposed with a predetermined gap from the developing roll and regulates the amount of developer conveyed on the developing roll, the seal member is used. A contact portion that abuts so as to press in the direction of fixing the holder member to the fitting portion provided in the housing when the developer regulating member is fixed to the housing. Is preferred.

When the above-mentioned developer regulating member is provided, the developer regulating member is in contact with a part of the holder member constituting the seal member, and the developer regulating member in the contact state. It is desirable to provide an interval setting rib having a shape in which a predetermined interval is ensured between the developing roller and the developing roller. In this case, it is desirable that the rib for setting the gap has a protrusion formed on the side facing the developing roll, the protrusion being worn or missing by the rotational force of the developing roll.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show an example of a developing device according to the present invention. FIG. 1 is a cross-sectional view showing the entire structure thereof, FIG. 2 is a cross-sectional view showing the main parts thereof, and FIG. 3 is a mounting state of a seal member. FIG.

The developing device 1 illustrated in FIG. 1 is a two-component developing device which uses a two-component developer consisting of carrier particles made of iron powder or the like and toner particles mainly made of resin, and is roughly shown. With respect to the housing 2 formed in a desired shape and the opening 2a formed in the housing 2, a part of the outer peripheral surface of the roll is exposed so that the roller rotates in the state of being close to the electrostatic latent image carrier 3. Developing roll 4 attached to
A developer agitating / supplying unit 6 provided to rotate inside the housing 2 on the back side of the developing roll 4, and a developer regulating member 7 disposed above the developing roll 4 with a predetermined gap. , A seal member 8 disposed between both ends of the developing roll 4 and the housing 2. In this example, a photosensitive drum is used as the electrostatic latent image carrier 3.

Here, the developing roll 4 may have any structure as long as it can carry the two-component developer 5 and convey it at least to the developing area facing the electrostatic latent image carrier 3. . In this example, as the developing roll 4, as shown in FIGS. 1 and 2, a fixedly supported substantially cylindrical magnet member 40 and a cylindrical sleeve body 41 installed so as to rotate around the outer periphery of the magnet member 40. I am using the one consisting of and. The above magnet member 40
Is a stripping pole N1 on a ferritic magnet roll,
A plurality of magnetic poles such as the attraction pole N2, the carrier poles S2 and N3, and the main developing pole S1 are sequentially magnetized, whereby regions (N2 to N3 to S1 to N1 to N1 to S1 to S1) in which magnetic poles having different magnetism are alternately continuous.
In the area (N1), the developer is held so as to form a magnetic brush, and in the area where the magnetic poles are arranged (areas N1 and N2), the developer is peeled off.

Further, the developer agitating and supplying means 6 may be any one capable of supplying the two-component developer 5 to the developing roll 4 while agitating it. In this example, the screw-shaped blades rotate. Two augers 6 standing on the roll
0 and 61 are used. These two augers 60,6
1 rotates in a state in which the developing roll 4 and the rotation axis are parallel to each other inside the housing 2 and within a region divided into two by a partition plate 62 provided upright in the middle of the housing 2. Are arranged as follows. Further, the augers 60 and 61 are set such that the rotation direction and the winding direction of the blades are set so that the developer conveying directions thereof are opposite to each other, whereby the developer 5 and the auger 61 are arranged in a region where the auger 60 is disposed. Are transported and circulated so as to alternately pass through the area where the is arranged. And the developer 5
Is attracted by the magnetic force of the attraction pole N2 at the time when the auger 60 on the side of the developing roll 4 is conveyed, and is carried on the developing roll 4 (sleeve body 41). .

Further, the developer regulating member 7 is not particularly limited as long as it can regulate the amount of the developer conveyed on the developing roll 4, and in this example, a plate-shaped blade (trimmer) is used. are doing. As shown in FIG. 2, the developer regulating member 7 is fixed to a portion of the housing 2 located above the developing roll 4 with a screw 70 or the like. At this time, the regulating member is positioned so that the lower end 7a thereof is separated from the surface of the developing roll 4 by a predetermined distance d.

As shown in FIGS. 2 and 3, the seal member 8 is arranged on the side in contact with the housing 2 and the sliding contact elastic member 80 arranged on the side in contact with the end 4a of the developing roll 4. The holder member 81 is made up of two parts.

The sliding contact elastic member 80 is a sheet-shaped seal member, and is made of Teflon (trade name) type felt or the like. The elastic member 80 is
Since it is in direct contact with the surface of the developing roller and is in sliding contact therewith, it is preferable that the surface has excellent lubricity.

On the other hand, the holder member 81 is a seal member having a shape having at least a curved surface-shaped accommodating portion 83 for holding the elastic member 80 for sliding contact, and is made of a plastic material such as nylon or polyacetal (POM). Is molded in.

In the holder member 81 in this embodiment, the plate-like member is bent along the peripheral surface on one side of the column, and the upper and lower end portions of the holder member 81 are slightly protruded inward toward the inside to hold inwardly. Provided with a locking projection 84,
The inner peripheral surface portion between 85 is used as the curved surface-shaped accommodating portion 83. Further, a flat plate-shaped rib 86 is provided on the tip end side of the upper locking convex portion 84 so as to vertically and outwardly project from the convex portion 84.

The plate-shaped rib 86 is formed to have a thickness corresponding to the distance d of the developer regulating member 7 with respect to the developing roll 4, and the lower end of the developer regulating member 7 is formed on the upper surface of the rib. Are in contact with each other. And rib 8
The outer peripheral surface of the locking convex portion 84 orthogonal to the upper surface of 6 is used as a contact portion 84a with which the inner surface of the lower end of the regulating member 7 abuts when the developer regulating member 7 is fixed to the housing 2. ing.

Further, as shown in FIG. 3, the holder member 81 is constructed so as to be detachably attached to a fitting portion 20 provided in a portion of the housing 2 where the end portion 4a of the developing roll is attached. The fitting portion 20 is
The holder member 81 has such a shape that the holder member 81 can be easily inserted into the housing from the lateral direction (along the axial direction of the developing roll) or can be pulled out in the opposite direction. Any shape may be used as long as it has a convex portion that locks at a position.

The seal member 8 composed of such a combination of the elastic member 80 for sliding contact and the holder member 81 is
It is installed as follows.

First, the sliding contact elastic member 80 is accommodated in the curved surface accommodating portion 83 of the holder member 81. The upper and lower ends of the elastic member 80 are securely held in the accommodating portion 83 by being locked by the locking projections 84 and 85 of the holder member 81. As a result, the seal member 8 is completed.
Next, the seal member 8 is attached by inserting the holder member 81 into the fitting portion 20 of the housing 2 from the lateral direction and fitting. After that, the housing 2
By attaching the developing roll 4 to the seal member 8
Is sandwiched between the developing roll 4 and the housing 2. Then, the lower end 7a of the developer regulating member is brought into contact with the upper surface of the rib 86 of the holder member 81, and the locking projection 8 is formed.
The screwing 70 is carried out in a state of being brought into contact with the contact portion 84a which is the outer peripheral surface of No. 4.

As a result, the seal member 8 is finally fixed so that the contact portion 84a of the holder member 81 is flush with the mounting surface of the lower end 7a of the developer regulating member. As a result, the seal member 8 is not displaced so as to rotate with the rotation of the developing roll 4. The developer regulating member 7 attached together with the seal member 8 is separated from the developing roll 4 by the rib 86 of the holder member 81.
Is set. Therefore, it is not necessary to adjust the distance d between the developer regulating members 7 using a gap gauge as in the conventional case.

Next, the operation of this developing device will be described.

The two-component developer 5 sufficiently agitated by the developer agitating and supplying means 6 is attracted to the developing roll 4 (actually the sleeve body 41) by the magnetic force of the attraction electrode N2 in the area where the auger 60 is arranged. As a result, the magnetic brush is formed, and the magnetic brush is conveyed by the rotation of the sleeve body 41 while being held by the magnetic field formed on the attraction pole N2 and the conveyance pole S3. In FIG. 2b, reference numeral 4b is the developing roll 4.
The area for carrying and conveying the developer is shown.

Developer 5 carried and carried on the developing roll 4.
The conveyance amount of the toner is regulated by the developer regulating member 7 which is disposed in the middle of the transportation corresponding to the gap between the attraction pole N2 and the transportation pole S3. That is, the height of the magnetic brush depends on the restriction member 7.
And the distance d between the developing rolls 4 is restricted. As a result, the developer 5 (magnetic brush) on the developing roll 4 has a constant layer thickness. The developer scraped off by the regulation member 7 is returned to the auger 60 side.

The developer 5 after passing through the developer regulating member 7.
Is transported to the developing area facing the electrostatic latent image carrier 3,
Therefore, only the toner particles adhere to the latent image portion of the electrostatic latent image carrier 3 to perform the development. On the other hand, the developer 5 after the development process is further conveyed as the sleeve body 41 rotates, and is separated from the developing roll 4 between the poles N1 and N2.

A seal member 8 is arranged at both ends 4a of the developing roll 4 on which the developer is carried and carried so as to close a gap formed between the roll end and the housing 2. Since it is provided, the course of the developer 5 that tries to pass through the gap is cut off. This prevents the developer from leaking between the housing and both ends of the developing roll.

The seal member 8 has an elastic member 80 for sliding contact therewith.
Is in contact with the end of the rotating developing roll, it will be worn due to long-term use, and its sealing effect will be reduced. In this case, the seal member 8 will be replaced.

When the seal member 8 is replaced, the above-mentioned mounting process of the seal member 8 can be carried out in the reverse order. However, in the case of this seal member 8, the developer regulating member 7 is used.
The seal member alone can be removed from the housing 2 without removing the developing roller 4 or the developing roller 4. That is, the seal member 8 (holder member 81) may be pulled out from the fitting portion 20 having the above-described configuration along the axial direction of the developing roll 4. Also, the worn elastic member 80 for sliding contact can be easily removed by pulling it from the accommodating portion 83 of the holder member 80. As a result, a new seal member 8 can be prepared simply by replacing only the elastic member 80 with a new one.

When the new seal member 8 is attached to the housing 2 again, the developer regulating member 7
When the developing roller 4 and the developing roller 4 are removed, the above-described work steps may be repeated in the same manner. In the case of the seal member 8, the housing 2 is fitted after the seal member is independently removed. Part 20 and developing roll 4
It can be easily carried out by inserting from the lateral direction into the gap formed between the peripheral surface of the end of the.

The seal member 8 can be further configured as follows.

For example, as shown in FIGS. 4 and 5, the protrusions 8 are arranged at arbitrary intervals in the curved housing portion 83 of the holder member 81.
7 may be provided. The projection 87 illustrated in FIG. 4 has a projection tip formed in a flat shape, and the projection 87 illustrated in FIG. 5 has a projection tip formed in a sharp shape. The shape and the number of the protrusions 87 are appropriately set within a range in which the sliding contact elastic member 80 is not excessively pressed from behind and deformed.

By providing the protruding portion 87, the surface of the sliding contact elastic member 8 on the housing portion 83 side is locked by the protruding portion 87, and as a result, the sliding contact elastic member 8 is formed.
Even when 0 receives the sliding contact force due to the rotation of the developing roll 4, the positional deviation does not occur in the accommodating portion 83. That is, it is possible to prevent the sealing effect from varying or decreasing due to the displacement of the sliding contact elastic member 80.

Further, in the above-mentioned example, the plate-shaped rib 86 is provided at the tip of the locking convex portion 84 of the holder member 81, and this rib 86 is used for setting the interval d of the developer regulating member 7. However, when the space between the developer regulating members 7 is set, the ribs 86 are fixed to the housing 2 by the mounting screws 70 while applying a constant load with the lower end of the regulating member facing the developing roll 4 side. For this reason, the rib 86 is in contact with the peripheral surface of the end portion of the developing roller 4, so that a certain amount of load is applied to the driving torque of the developing roller 4. Therefore, in order to reduce the load as much as possible, for example, as illustrated in FIGS. 4 and 5, on the side of the rib 86 for setting the interval facing the developing roll, the protruding portion 88 where the contact area with the developing roll 4 is reduced.
Can be provided. Further, in order to eliminate the load on the developing roll of the space setting rib, the above-mentioned protrusion 88 is formed.
May be configured as shown in FIGS. 6 and 7.

That is, the protrusion 88a illustrated in FIG.
The tip end portion is configured to be immediately worn by sliding friction with the developing roll 4. This protrusion 88
In the case of "a", the tip portion is formed into a sharp shape so as to be easily worn. With this protrusion 88a, it is possible to set the interval d of the developer regulating member 7 when the seal member or the like is attached (FIG. 6a), while the developing roll 4 rotates after the interval is set. As a result, the tip portion is worn away, and the tip portion can be separated (S) from the peripheral surface of the roll end portion (FIG. 6b). As a result, it is possible to avoid an increase in the drive torque of the developing roll due to the protrusion 88a.

Further, the projection 88b illustrated in FIG. 7 is constructed so that the tip end thereof is immediately broken by the sliding friction with the developing roll 4 and is lost. The protruding portion 88a shown in the figure has a structure in which the tip portion thereof is provided on the rib 86 by a connecting portion 89 which is easily broken. This protrusion 8
According to 8b, it is possible to set the interval d of the developer regulating member 7 when the seal member or the like is attached (see FIG. 7).
a) On the other hand, after the interval setting, the developing roller 4 rotates to drop the leading end portion, and the leading end portion can be separated (S) from the peripheral surface of the roll end portion (FIG. 7).
b). As a result, it is possible to avoid an increase in the drive torque of the projecting portion 88b developing roller.

The present invention is not limited to a two-component developing device,
It may be a one-component developing device that uses a one-component developer. Further, the developing device of the present invention can be applied to an image forming apparatus such as a copying machine and a printer using an electrophotographic method. FIG. 8 shows an example in which the developing device 1 is applied to an image forming apparatus using an electrophotographic method. In this case, the image forming apparatus operates in a known cycle, the electrostatic latent image formed on the photosensitive drum 3 is developed by the developing device 1, and the developed toner image is transferred to a predetermined recording paper P. The image is formed by transferring the image onto the sheet and then fixing it. Further, in the developing device 1, since the development member is reliably prevented from leaking due to the seal member 8, there is almost no occurrence of contamination inside the machine due to such developer leakage.

In FIG. 8, reference numeral 100 is a charging device, 101 is a laser image writing device, 102 is a transfer device, 103 is a peeling device, 104 is a cleaning device, and
105 is a static eliminator, 106 is a conveyor belt, 107 is a fixing device, 108 is a discharge tray, 109 is a first paper tray,
110 is a second paper tray.

[0046]

As described above, in the developing device of the present invention, since the seal member is configured as described above, the seal member ensures more reliable and stable developer leakage from both ends of the developing roll. It is possible to easily prevent the seal member from being attached and replaced.

Moreover, since the sealing member is not attached to the housing with an adhesive tape or an adhesive, it can be cleanly removed from the housing and the constituent parts can be easily separated, which is suitable for recycling. is there.

When a rib for setting the gap of the developer regulating member is provided on a part of the holder member constituting the seal member, the developer regulating member is secured at a predetermined distance from the developing roll. While installing, it can be done easily and accurately.

[Brief description of drawings]

FIG. 1 is a conceptual cross-sectional view showing an example of a developing device according to the present invention.

FIG. 2 shows the configuration of the main part of the developing device,
(A) is the sectional view and (b) is the front view.

FIG. 3 is an exploded explanatory view showing a configuration of a seal member.

4A and 4B show a modified example of a holder member of a seal member, FIG. 4A is a perspective view thereof, and FIG. 4B is an explanatory view showing a usage state thereof.

5A and 5B show another modified example of the holder member of the seal member, FIG. 5A is a perspective view thereof, and FIG. 5B is an explanatory view showing a usage state thereof.

6A and 6B are views showing a modified example of a space setting rib of a holder member, wherein FIG. 6A is an explanatory view showing a usage state when the space is set, and FIG. 6B is an explanatory view showing a usage state after the space is set. Is.

7A and 7B are views showing another modified example of the space setting ribs of the holder member, wherein FIG. 7A is an explanatory view showing a usage state when the space is set, and FIG. 7B shows a usage state after the space is set. FIG.

FIG. 8 is an explanatory diagram showing an example of an image forming apparatus to which the developing device according to the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Developing device, 2 ... Housing, 2a ... Opening part, 3 ... Electrostatic latent image carrier, 4 ... Developing roll, 5 ... Developer, 7 ... Developer regulating member, 8 ... Seal member, 20 ... Fitting part, 80
... Sliding contact elastic member, 81 ... Holder member, 83 ... Curved surface accommodating portion, 84a ... Contact portion, 86 ... Interval setting rib, 8
7 ... Protrusions for preventing positional displacement, 88 ... Protrusions for spacing setting ribs, 88a ... Worn protrusions, 88b ... Missing protrusions, d ... Predetermined intervals.

Claims (6)

[Claims] 1. A housing of a developing device, and an opening formed in the housing, which is mounted so as to rotate in a state of being close to an electrostatic latent image carrier, and carries a developer to carry the electrostatic latent image carrier. A developing device comprising: a developing roll that conveys to a developing area facing the body; and a sealing member that prevents developer leakage between both ends of the developing roll and the housing. Of the elastic member for sliding contact arranged on the side in contact with the end portion of the holder, and a holder member having a curved surface accommodating portion for holding the elastic member for sliding contact and arranged on the side in contact with the housing. And is configured to be detachably attached to the fitting portion of the holder member provided in the portion of the housing to which the developing roll end portion is attached. Image apparatus. 2. The developing device according to claim 1, wherein the elastic member for sliding contact is detachably held in the curved surface accommodating portion of the holder member. 3. The developing device according to claim 2, wherein a protrusion for preventing displacement of the sliding contact elastic member is provided in the curved surface-shaped accommodating portion of the holder member. 4. The seal member comprises a developer regulating member which is disposed with a predetermined gap from the developing roll and regulates the amount of developer conveyed on the developing roll. 2. The developing device according to claim 1, wherein a contact portion is provided on a part of the holder member, the contact portion being in contact with the developer regulating member so as to press when the developer regulating member is fixed to the housing. 5. The seal member comprises a developer regulating member which is disposed at a predetermined distance from the developing roll and regulates the amount of developer conveyed on the developing roll. An interval setting rib having a shape in which a part of the holder member is in contact with the developer restricting member and a predetermined interval is provided between the developer restricting member in the contacted state and the developing roll. The developing device according to claim 1, wherein the developing device is provided. 6. The gap setting rib provided on a part of the holder member has a projection portion, which is worn or lacked by the rotational force of the developing roller, on the side facing the developing roller. Development device.