JP2001183903A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device which allows preventing the toner from scattering effectively, keeping picture quality and parts in the device excellently thereby and unnecessitating the maintenance for removing the toner periodically. SOLUTION: A seal-like member 6 which extends over the entire region in the width direction of a developing roll 2 is disposed on the tip part of a frame 18 of the developing device. The seal-like member 6 is made to be a thin and almost rectangular sheet having the thickness of 0.1-0.2 mm and is constituted of the material having flexibility and low frictional resistance. One side of long sides of the seal-like member 6 is stuck to the upstream side of a toner passage 19 from a tip of the back surface of the frame 18 via a double coated adhesive tape 61 and, on the other hand, the other side is stuck on the lower surface of the tip part of the frame 18 via the double coated adhesive tape 61. The other side of the seal-like member 6 is curved and protruded toward the toner passage 19 and the curved part is brought into soft contact with a developing brush G on the developing roll 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device in an electrophotographic image forming apparatus such as a copying machine, a printer and a facsimile, and more particularly, to a developer scatter (toner scatter) and a printing by dropping the scattered toner. Related to measures to prevent quality deterioration.

[0002]

2. Description of the Related Art Generally, in an electrophotographic image forming apparatus such as a copying machine, a printer and a facsimile,
The developer on the surface is sequentially supplied (operated) to the photoreceptor that carries and transports the electrostatic latent image from the circumferential direction by the rotation of a developing roller of a developing device that holds the developer on the surface. The image is developed on the surface (electrostatic latent image). Then, the developer on the developing roller is brushed on the developing roller by a spike height regulating blade provided on the upstream side in the rotation direction of the developing roller from an opposing portion facing the photoconductor (developer). Is regulated, and in this state, it is fed to the portion facing the photoconductor through the developer flow path and supplied to the electrostatic latent image on the surface of the photoconductor.

In this case, since the developer flow path at the corresponding portion of the developing roller corresponding to the downstream side in the rotation direction of the developing roller from the ear height regulating blade is exposed to the outside, the rotation of the developing roller causes the developer to flow on the surface thereof. Until the developer whose layer thickness is regulated is supplied to the photoreceptor, it is necessary to prevent the developer from scattering from the developer flow path to the outside.

For this reason, conventionally, as shown in FIG. 13, a frame b that covers the developer flow path a downstream of the developing roller e with respect to the ear height regulating blade c from outside is utilized by using a frame body d of the developing device. Of the frame b (frame d) located on the downstream end side in the rotation direction of the developing roller e (the developing roller e
At the downstream end in the rotation direction of the photoconductor f, an opening g is formed in the frame d so as to face the developing roller e to the photoconductor f, and is located downstream of the opening g in the rotation direction of the photoconductor f. A seal member h is provided at the end of the frame b to be in contact with the photoreceptor f to prevent the developer from scattering from the developer flow path a.

[0005]

However, in the above-described conventional developing device, as shown in FIG. 13, a gap exists between the frame b and the developing brush i formed on the developing roller e. The developer scattered from the developer flow path a adheres to the frame b and gradually accumulates. The accumulated developer falls into the developer flow path a due to internal vibration, rubbing of the developing brush i, and its own weight, and further falls on paper, a transfer belt, and the like as the developing roller e rotates. This causes poor image quality and stains on the in-flight parts.

Therefore, for example, as shown in FIG. 14, a resin-made sealing member j whose tip projects toward the developing roller e is provided at the tip of the frame b, or as shown in FIG. A gap between the frame b and the developing roller e is closed at the front end of the frame b, for example, by providing a seal-shaped member k made of a flexible elastic body whose front end projects toward the developing roller e at the front end of the frame b. It is conceivable to prevent the developer adhering and accumulating on the frame b from scattering from the developer flow path a to the outside.

However, in these proposals,
Since the seal members j and k themselves have poor flexibility, when the seal members j and k come into contact with the surface of the developing brush i on the developing roller e, the developing brush i is strongly pressed, resulting in poor standing or longitudinal direction. In such a case, adverse effects such as non-uniformity of the supply amount of the developer are caused, which causes image unevenness.

Further, in the seal-like members j and k having poor flexibility as in these proposals, the developer scattered from the developer flow path a when the developing brush i is strongly pressed is placed on the seal-like member j. (Contact surface with the developing brush). In this case, the frame b and the sealing member j are located downstream of the developer flow path a in the rotation direction of the developing roller e.
(Or a seal member k), a latent image carrier such as a photoreceptor f, a developing roller e, and a space m surrounded by a seal member h, the developer accumulated on the seal member j. Will fall into the space m and fall on the latent image carrier while the latent image carrier is rotating, etc., and this developer is loaded on the latent image carrier and is on paper or a transfer belt. Will fall. For this reason, these proposals cannot be a solution to the cause of the poor image quality or the contamination of the in-machine parts, and in addition, the maintenance must be performed regularly to remove the developer accumulated on the seal member j. There is a need to do.

SUMMARY OF THE INVENTION The present invention has been made in view of the foregoing, and it is an object of the present invention to effectively suppress the prevention of the developer from scattering, improve the image quality and the in-machine parts, and perform the periodic operation. Another object of the present invention is to provide a developing device which can eliminate the need for maintenance for removing the developer.

[0010]

In order to achieve the above object, according to the present invention, as a developing device, a developing device is provided at a portion opposed to a latent image carrier for carrying and transporting an electrostatic latent image. An opening portion of the frame body that opens in a width direction orthogonal to the transport direction, and a developer provided on the surface of the latent image carrier, which is provided to face the surface of the latent image carrier with the opening portion interposed therebetween. A developing roller for developing an image on the surface of the latent image carrier by acting on the latent image with its own rotation; and a developing roller provided upstream of the opening in the direction of rotation of the developing roller and held by the developing roller. A layer thickness regulating member for regulating the layer thickness of the developer, a developer flow path covered from outside by a frame between corresponding portions corresponding to the layer thickness regulating member and the opening of the developing roller, and the opening, Is provided on the downstream side in the transport direction of the latent image carrier from the A sealing member that comes into contact with the holding member, and a curved portion that is provided across the width direction of the developing roller at the periphery of the opening located on the upstream side in the rotation direction of the developing roller and that projects toward the developer flow path. A sealing member made of a material that is soft and has low frictional resistance so as to make soft contact with the developer on the developing roller.

In this case, the seal member made of a material that is soft and has low frictional resistance is directed toward the developer flow path at the leading end of the frame, that is, at the periphery of the opening located on the upstream side in the rotation direction of the developing roller. Since the protruding curved portion makes soft contact with the surface of the developing brush (developer) on the developing roller, the developing brush is strongly pressed like a poorly flexible seal member such as a resin or a flexible elastic body. Never. For this reason, it is possible to form a stable image without unevenness without causing any adverse effects such as poor standing of the developing brush and uneven supply of the developer in the longitudinal direction.

Further, when the curved portion of the seal member comes into soft contact with the developing brush on the developing roller, the developer adhering to the seal member loses the developing brush ears on the surface (curved surface) of the seal member. ) Is scraped off by rubbing, and the accumulation of the developer on the seal-like member is prevented.
For this reason, the developer is prevented from falling into the space surrounded by the frame and the seal-like member, the latent image carrier, the developing roller, and the sealant, and from above the latent image carrier onto the paper or the transfer belt. For example, the developer does not fall down, and it is possible to effectively prevent poor image quality and contamination of parts in the machine. In addition, the developer attached to the seal member is scraped off by the rubbing of the developing brush ears, thereby eliminating the accumulation of the developer on the seal member and maintaining the developer on a regular basis. Can be eliminated.

On the other hand, in the case where the sealing member made of a soft and low frictional material is configured such that its curved portions are in soft contact with the latent image carrier and the developer on the developing roller, respectively, The curved portion of the seal member makes soft contact with the surface of the latent image carrier and the surface of the developing brush (developer) on the developing roller, and the developing brush is gently and slowly pressed while sealing the surface of the latent image carrier. Will be.
This eliminates the need for a sealing material downstream of the opening in the conveyance direction of the latent image carrier, and seals the surface of the latent image carrier with a seal-shaped member located around the opening located upstream in the rotation direction of the developing roller. On the other hand, it is possible to form a stable image by eliminating image unevenness due to adverse effects such as poor standing of the developing brush and uneven supply of the developer in the longitudinal direction.

Further, when the curved portion of the seal member comes into soft contact with the developing brush on the developing roller, the developer adhering to the seal member loses the developer brush on the surface (curved surface) of the seal member. ) Is scraped off by rubbing, and the accumulation of the developer on the seal-like member is prevented.
For this reason, the developer does not fall from the latent image carrier onto the paper or the transfer belt through a space surrounded by the frame and the seal-like member, the latent image carrier, and the developing roller. It is possible to effectively prevent defects and dirt on the internal components.

[0015] In particular, the following configuration is provided to facilitate the attachment of the seal-like member.

That is, at least one of the two long side edges of the seal member is attached to the longitudinal edge of the opening together with the reinforcing member for reinforcing the long side of the seal member. In this case, at least one of the long side edges of the sealing member made of a soft and low frictional resistance material has a stable shape due to the strength of the reinforcing member itself, and an opening located on the upstream side in the rotation direction of the developing roller. When sticking to the peripheral edge, the seal-like member is smoothly stuck without causing waving or distortion. In addition, the strength of the reinforcing member itself reinforces the seal-like member even after sticking, stabilizing the shape of the long side, and applying uniform pressure to the surface of the developing roller in the longitudinal direction thereof. Can be brought into soft contact.

On the other hand, when a seal member made of a material that is soft and has low frictional resistance is configured such that an abdominal portion having an annular cross section protruding toward the developer flow path is in soft contact with the developer in the developer flow path. In this case, the developing brush is gently and gently pressed by the abdomen of the seal-shaped member, so that soft contact with the developing roller (developing brush) is stably performed. In addition, when the seal-like member is attached, the seal-like member can be easily handled because of its annular cross section, and the mounting workability can be improved.

In particular, the following configuration is provided to stabilize the contact with the developing roller.

That is, when the seal-like member is formed in a substantially annular shape in cross section or in a substantially semi-annular shape in cross section, the antinode of the seal-like member comes into linear contact with the developing brush on the developing roller only in a tangential direction. Thus, the soft contact with the developing roller is performed more stably.

On the other hand, the following structure is proposed to stabilize the contact pressure with the developing roller.

That is, when the elastic foam is filled in the inside of the sealing member, the abdomen of the sealing member always comes into contact with the developing brush on the developing roller with a stable contact pressure from the longitudinal direction, and the developing roller contacts the developing roller. Stable soft contact will be performed effectively.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a cross-sectional view illustrating an example of a developing device according to the embodiment.

In FIG. 1, a developing device X is of a sleeve type using a two-component developer, and has a container-like developing tank 1 as a frame for containing a toner as a developer.
A developing roller 2 rotatably housed in a lower portion of the developing tank 1 and a rotatably connected rotatable one side (the right side in the figure) of the developing roller 2 such that outer peripheral surfaces thereof face each other;
A stirring roller 3 for conveying or stirring the toner in the developing tank 1
And a pair of agitating screw rollers 4 and 5 rotatably provided near one upper side of the developing roller 2 and the agitating roller 3 and supplying and circulating toner at the upper part of the developing tank 1.

The developing roller 2 is provided with a cylindrical sleeve 21 made of a non-magnetic material, and is provided in the sleeve 21. The developing roller 2 has five magnetic poles S1, N1, S3 in the rotation direction (the direction of the arrow shown in the figure) by radiation extending from the center. , S2, and N2 in this order. In this case, the developing roller 2 is rotatable by rotation of the sleeve 21 with respect to the fixed magnet roller 22.

The magnetic pole S 2 of the magnetic poles S 1, N 1, S 3, S 2, N 2 is located at a pumping position facing the stirring roller 3. At the magnetic pole S2, the toner from the stirring roller 3 is pumped up. Magnetic pole S2
On the other hand, at the magnetic pole N2 adjacent in the rotation direction of the sleeve 21, the toner pumped by the magnetic pole S2 is brushed to form a developing brush G on the surface of the sleeve 21 (on the developing roller 2). . At the magnetic pole S1 adjacent to the magnetic pole N2 in the rotation direction of the sleeve 21, the magnetic pole N1 is maintained while the developing brush G is attached to the developing roller 2.
To be transported. The magnetic pole N1 is arranged at a developing position facing the surface of the photosensitive drum D as a latent image carrier that carries and conveys the electrostatic latent image. This magnetic pole N
In step 1, the developing brush G is rubbed (acted) on the surface of the photosensitive drum D, and toner is adhered to the electrostatic image on the surface of the photosensitive drum D to develop the toner image as a toner image. At the magnetic pole S3 adjacent to the magnetic pole N1 in the rotation direction of the sleeve 21, the toner (developing brush G) that does not contribute to the development is separated from the surface of the developing roller 2 by a magnetic force relationship with the magnetic pole S2. I have. The toner separated from the surface of the developing roller 2 at the magnetic pole S3 is taken into the stirring roller 3 side. In this case, the length of the developing roller 2 in the axial direction is slightly longer than the developing range of the electrostatic image on the photosensitive drum D, and is substantially equal to the axial length of the photosensitive drum D.

The stirring roller 3 rotates in the direction of the arrow shown in the figure, and sufficiently stirs the toner separated from the surface of the developing roller 2 at the magnetic pole S3 of the magnet roller 22 in preparation for the next development. To be supplied to the apparatus.

Between the photosensitive drum D and a facing portion of the developing roller 2 facing the photosensitive drum D (near the boundary between the magnetic pole S1 and the magnetic pole N1), the rotation direction (transport direction) of the photosensitive drum D is perpendicular to the photosensitive drum D. A long, substantially rectangular opening 11 having a cutout in the lower portion of the developing tank 1 is provided over the width direction of the developing tank 1.
In this case, the developing roller 2 faces the surface of the photosensitive drum D with an opening 11 cut out along the outer peripheral surface thereof.

At a position upstream of the opening 11 in the rotation direction of the developing roller 2, that is, radially outward of the magnetic pole N 2, a spike height as a layer thickness regulating member for regulating the layer thickness of the toner held by the developing roller 2. A regulating blade 12 is provided.
The ear height regulating blade 12 is formed over the width direction of the developing roller 2. And Hotaka regulation blade 12
The toner removed (regulated) is sent to the upper portion of the developing tank 1 through an inlet 13 that opens to one side of the spike height regulating blade 12. In this case, the developing tank 1 is
Are separated by a vertical line.

Each of the stirring screw rollers 4 and 5 is disposed above the partition 14. One stirring screw roller 4 (the left stirring screw roller in the figure) near one side of the upper side of the developing roller 2 is provided with a toner supplied from a toner supply port 15 opening thereabove and an inlet 13.
Is mixed with the toner taken in from above, and is conveyed and delivered to the other stirring screw roller 5 (the stirring screw roller on the right side in the figure) which is closer to the upper side of the stirring roller 3.
The other stirring screw roller 5 rotates in the opposite direction to the one stirring screw roller 5 as indicated by an arrow in the drawing, and similarly stirs the toner delivered from the one stirring screw roller 4. The toner is gradually dropped onto the stirring roller 3 through a return port 16 opened to the partition 14 below the other stirring screw roller 5 and returned.

Below the stirring roller 3, a developing device X
A toner density detecting sensor 17 for detecting the density of the toner inside (in the developing tank 1) is provided. The detection signal of the toner concentration detection sensor 17 is transmitted to a controller (not shown).
And the controller determines the toner density based on the detection result of the toner density detection sensor 17. Here, when the controller determines that the toner concentration in the developing device X is lower than the reference value, the toner supply motor (not shown) is driven, and the new toner stored in the toner hopper (not shown) is removed. The toner is supplied onto one of the stirring screw rollers 5 through the toner supply port 15 by the rotation of the toner transport roller and the toner supply roller which are not used. The toner supply operation stops when the toner concentration in the developing device X reaches the reference value due to the toner supply.

A toner flow path 19 as a developer flow path for transporting toner (developing brush G) between the spike height regulating blade 12 of the developing roller 2 and a portion corresponding to the opening 11 is provided in the developing tank 1. Is covered from the outside by a frame 18 provided integrally with the frame. A base end of a sealing material 10 whose front end is in contact with the surface of the photosensitive drum D is adhered downstream of the opening 11 of the frame 18 in the rotation direction of the photosensitive drum D. The seal material 10 extends over the entire width of the photosensitive drum D in the width direction.

As a characteristic portion of the present invention, as shown in FIGS. 2 and 3, the upper edge of the opening 11 located on the upstream side in the rotation direction of the developing roller 2, ie, the frame 1
8 has an entire area in the width direction of the developing roller 2 (opening 1).
1 (the entire area in the longitudinal direction). This seal-shaped member 6 has a thickness of 0.1 mm.
It has a thin, substantially rectangular sheet shape of about 1 mm to 0.2 mm and is made of a material having flexibility and low friction resistance, for example, a material such as polyurethane rubber coated with a high molecular polymer. One side (upper side in FIGS. 2 and 3) of the long side (long side in the longitudinal direction) of the seal-shaped member 6 has a double-sided tape 61 (shown in FIG. 3) via a double-faced tape 61 (shown in FIG. 3). ) Is attached to the upstream side of the toner flow path 19 from the front end, that is, is adhered from the corresponding position on the back side substantially corresponding to the base end of the sealing material 10 on the front side to the upstream side of the toner flow path. The other side (the lower side in FIGS. 2 and 3) is a longitudinal edge of the opening 11 via a double-sided tape 61 (shown in FIG. 3), that is, the lower surface of the leading end of the frame 18 (confronts the photosensitive drum D). Surface). The other side of the long side of the seal member 6 has a PET as a reinforcing member for reinforcing the long side of the seal member 6 on its sticking surface.
Film (polyethylene terephthalate film)
A reinforcing blade member 62 (shown in FIG. 3) is adhered to the reinforcing blade member 62, and is adhered to the lower surface of the distal end portion of the frame 18 via a double-sided tape 61. Then, the seal-shaped member 6 is attached to surfaces (the back surface of the frame 18 and the lower surface of the distal end portion) where the long sides on both sides intersect at an acute angle with each other.
The other side (the lower surface of the front end of the frame 18) is the toner flow path 1
The projection is curved and protrudes toward the developing roller 9 so that the curved portion (projecting portion) is brought into soft contact with the developing brush G (toner) on the developing roller 2.

In FIGS. 2 and 3, M denotes the frame 18 and the seal member 6, the photosensitive drum D, and the developing roller 2 on the downstream side of the toner flow path 19 in the rotation direction of the developing roller 2. , And a sealing material 10.

In the case of the present embodiment, the seal-like member 6 made of a material that is flexible and has low frictional resistance is attached to the surfaces (the back surface of the frame 18 and the lower surface of the tip end) where the long sides of both sides cross each other at an acute angle. By being attached, the curved portion (projecting portion) on the other side (the lower surface of the front end portion of the frame 18) that projects while curving toward the toner flow path 19 is attached to the developing brush G (toner) on the developing roller 2. On the other hand, the developing brush is softly pressed, so that the developing brush is not strongly pressed as in the case of a poorly flexible sealing member such as a resin or a flexible elastic body. For this reason, it is possible to form a stable image without unevenness, without causing adverse effects such as poor standing of the developing brush G and uneven supply of toner in the longitudinal direction.

When the curved portion of the seal-shaped member 6 comes into soft contact with the developing brush G on the developing roller 2, the toner adhering to the seal-shaped member 6 loses the spikes of the developing brush G. Is rubbed off by rubbing the surface (curved surface), thereby preventing the accumulation of toner on the seal-like member 6. For this reason, the toner is prevented from falling into the space M surrounded by the frame 18, the seal-shaped member 6, the photosensitive drum D, the developing roller 2, and the sealant 10, and the toner is transferred from the photosensitive drum D to the paper. It is possible to effectively prevent poor image quality and contamination of internal components without causing toner to fall onto the transfer belt or the like. In addition, the maintenance that removes the toner on the seal member 6 by removing the toner on the seal member 6 by removing the toner adhered on the seal member 6 by the rubbing of the ears of the developing brush G by the rubbing of the ears of the developing brush G Can be eliminated.

Further, since the other side of the long side of the sealing member 6 is adhered to the lower surface of the front end portion of the frame 18 by the double-sided tape 61 via the reinforcing blade member 62 adhered to the adhering surface, The other side of the long side of the seal member 6 made of a soft and low-frictional material has a stable shape due to the strength of the reinforcing blade member 62 itself. Can be smoothly adhered without causing waving or distortion. In addition, the strength of the reinforcing blade member 62 itself reinforces the seal-like member 6 even after sticking, stabilizing its shape, and applying uniform pressure to the developing brush G on the developing roller 2 in the longitudinal direction thereof. The sealing member 61 can be in soft contact. As a result, the stable performance of the developing device X can be exhibited.

Here, in evaluating the performance of the developing storage X according to the present embodiment, the performance is compared with the comparative example 1 shown in FIG. 13, the comparative example 2 shown in FIG. 14, and the comparative example 3 shown in FIG. An experimental result will be described based on FIG. In this case, the conditions of the experiment were as follows: a band chart having a solid area ratio of 10% was used, and a toner whose toner concentration was 3% higher than usual was used.
No accelerated test aging of 0 sheets is performed.

From the experimental results shown in FIG. 4, in the developing device X of the first embodiment, the number of toner particles dropped on paper
One-fifth of that in Comparative Example 3, which is one-fifth, indicating that very excellent performance can be obtained.

Further, it was also found that in the developing device X of the first embodiment, adverse effects such as poor standing were hardly generated as compared with those of Comparative Examples 2 and 3.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIGS.

In this embodiment, the structures of the sealing member and the sealing material are changed. The other configuration except for the sealing member and the sealing material is the same as that of the first embodiment, and the same portions are denoted by the same reference numerals and description thereof will be omitted.

That is, in the present embodiment, as shown in FIGS. 5 and 6, the seal-shaped member 7 is located at the upper edge of the opening 11 located on the upstream side in the rotation direction of the developing roller 2 from the opening 11, ie, At the leading end of the frame 18, it is provided to extend over the entire area in the width direction of the developing roller 2 (the entire area in the longitudinal direction of the opening 11). The seal-like member 7 has a thin, substantially rectangular sheet shape with a thickness of about 0.1 mm to 0.2 mm, and is made of a material having flexibility and a low frictional resistance, such as a polyurethane rubber coated with a polymer. Made of material. The seal-like member 7 has one side (the upper side in FIGS. 5 and 6) of its long side (side in the longitudinal direction).
Through the double-sided tape 71 (shown in FIG. 6)
8 is adhered from a position (a position substantially corresponding to the base end of the seal material 10) away from the front end of the rear surface (the side surface of the toner flow path 19) from the front end to the upper side, while the other side (FIG. The lower surface in FIG. 6 is a front edge surface of the longitudinal direction of the opening 11 via the double-sided tape 71, which is shown in FIG. It is stuck on. The above-mentioned sealing member 7
On the other side of the long side, a reinforcing blade member 72 (shown in FIG. 6) made of a PET film (polyethylene terephthalate film) as a reinforcing member for reinforcing the long side of the seal-shaped member 7 on its sticking surface. Is attached to the reinforcing blade member 72 via the double-sided tape 71.
Is attached to the surface of the distal end portion. The seal-shaped member 7 is adhered to the surfaces (the back surface and the front end surface of the frame 18) whose long sides on both sides are substantially parallel to each other, so that the other side (the frame 18
Of the photosensitive drum D and then project toward the toner flow path 19 while curving. The curved portion (protruding portion) is developed on the surface of the photosensitive drum D and on the developing roller 2. The brushes G (toner) are each brought into soft contact with each other.

Note that M 'in FIGS. 5 and 6 is
On the downstream side of the toner flow path 19 in the rotation direction of the developing roller 2, a space surrounded by the seal member 7, the photosensitive drum D, and the developing roller 2.

In the case of the present embodiment, the seal-like member 7 made of a material that is soft and has low frictional resistance is adhered to surfaces (the back surface and the front end surface of the frame 18) whose long sides on both sides are substantially parallel to each other. As a result, the curved portion (projecting portion) on the other side (the lower surface side of the front end portion of the frame 18) that projects toward the toner flow path 19 while bending toward the photoconductor drum D side is projected. And the developing brush G (toner) on the developing roller 2 is in soft contact, so that the developing brush G is gently and gently pressed while sealing the surface of the photosensitive drum D.
For this reason, a sealing material on the downstream side of the photosensitive drum D in the transport direction from the opening 11 becomes unnecessary, and the sealing member 7 at the end of the frame 18 seals the surface of the photosensitive drum D while the developing brush G It is possible to form a stable image by eliminating image unevenness due to adverse effects such as poor earing and uneven toner supply in the longitudinal direction.

When the curved portion of the seal member 7 comes into soft contact with the developing brush G on the developing roller 2, the toner adhering to the seal member 7 loses the The surface (curved surface) is scraped off by rubbing, and the accumulation of toner on the seal member 7 is prevented. For this reason, the toner does not drop onto the paper or the transfer belt from the photosensitive drum D via the space M 'surrounded by the seal member 7, the photosensitive drum D, and the developing roller 2, It is possible to effectively prevent poor image quality and dirt on in-machine parts.

Here, in order to evaluate the performance of the developing storage device according to the present embodiment, an experiment comparing the performance with Comparative Example 1 shown in FIG. 13, Comparative Example 2 shown in FIG. 14, and Comparative Example 3 shown in FIG. Is performed under the same conditions as in the first embodiment, and the experimental results are shown in FIG.

From the experimental results shown in FIG. 7, in the developing device of the second embodiment, as in the case of the developing device X of the first embodiment, the number of toner drops on paper is one hundredth of that of Comparative Example 1. ,
This is one-fifth of that of Comparative Example 3, indicating that very excellent performance can be obtained.

Also, in the developing device of the second embodiment, problems such as poor spikes hardly occur as compared with those of Comparative Examples 2 and 3.

<Third Embodiment> Next, a third embodiment of the present invention will be described.
An embodiment will be described with reference to FIGS.

In this embodiment, the structure of the seal member is changed. The other configuration except for the seal member is the same as that of the first embodiment, and the same portions are denoted by the same reference numerals and description thereof will be omitted.

That is, in the present embodiment, as shown in FIGS. 8 and 9, the seal-shaped member 8 has the upper edge of the opening 11 located on the upstream side in the rotation direction of the developing roller 2 with respect to the opening 11, that is, On the rear surface of the leading end of the frame 18, the developing roller 2 extends over the entire area in the width direction of the developing roller 2 (the entire area in the longitudinal direction of the opening 11). This sealing member 8
It has a thin annular shape with a thickness of about 0.1 mm to 0.2 mm, specifically a substantially track-shaped cross section with a hollow inside, and is coated with a material having flexibility and low friction resistance, for example, a polymer. It is made of a material such as polyurethane rubber. One of the two long sides of the seal member 8 (the left side in FIGS. 8 and 9) is adhered to the back surface of the front end portion of the frame 18 via a double-sided tape 81 (shown in FIG. 9). I have. The seal-shaped member 8 has one long side of the long diameter adhered to the back surface of the front end of the frame 18, so that the center of the other side (the right side in FIGS. 8 and 9) has toner abdomen. The abdomen (protruding portion) projects toward the path 19 and is brought into soft contact with the developing brush G (toner) on the developing roller 2.

In the case of the present embodiment, the developing brush G on the developing roller 2 is gently and gently pressed by the abdomen of the other long side of the seal member 8 made of a soft and low frictional resistance, and the developing roller 2 (developing) Soft contact with the brush G) can be performed stably.

In addition, when the seal-like member 8 is adhered, the seal-like member 8 can be easily handled because of its annular cross section, and the mounting workability can be improved.

Here, in order to evaluate the performance of the developing storage device according to the present embodiment, an experiment for comparing the performance with Comparative Example 1 shown in FIG. 13, Comparative Example 2 shown in FIG. 14, and Comparative Example 3 shown in FIG. Is performed under the same conditions as in the first embodiment, and the experimental results are shown in FIG.

From the experimental results shown in FIG. 10, the number of toner drops on the paper in the developing device of the third embodiment is 1/100 as in the case of the developing device X of the first embodiment. In addition, it is one-tenth of that of Comparative Example 3, and it can be seen that very excellent performance can be obtained.

Also, in the developing device of the third embodiment, problems such as poor spikes hardly occur as compared with those of Comparative Examples 2 and 3.

<Other Embodiments> In the third embodiment, the seal-like member 8 having a substantially track-shaped cross section and having a hollow inside is used. However, as shown in FIGS. 11 and 12, a substantially semicircular cross section is used. An annular seal member 9 may be used, and the flat portion of the seal member 9 is attached to the back surface of the front end portion of the frame 18 via a double-sided tape 91, so that the semi-circular abdomen is formed. The protruding portion (protruding portion) projects toward the toner flow path 19, and is brought into soft contact with the developing brush G (toner) on the developing roller 2. In this case, the antinode of the seal-shaped member 9 makes linear contact with the developing brush G on the developing roller 2 only in the tangential direction, and the soft contact with the developing roller 2 can be performed more stably.

In the second embodiment and the other embodiments described above, since the material is hollow, the material is brought into soft contact with the developing brush G on the developing roller 2 by the elastic force of the material itself. The hollow portion of the seal-like member may be filled with an elastic foam such as polyurethane foam or polyethylene foam. In this case, a stable pressure is applied to the seal-shaped member, and the abdomen constantly contacts the developing brush on the developing roller with a stable contact pressure from the longitudinal direction,
Stable soft contact with the developing roller can be effectively performed.

Further, in the first and second embodiments, the other side of the long side of the sealing member 6 (or 7) is connected to the double-sided tape 6 via the reinforcing blade member 62 (or 72).
1 (or 71), but one side of the long side of the seal-like member may be adhered to the back side of the frame with a double-sided tape via a reinforcing blade member. In this case, the long sides of both sides of the seal-like member are stable in shape due to the strength of the two reinforcing blade members themselves, and when sticking to the frame, the seal-like member is smoothly attached without waving or distortion. You can wear it. In addition, the strength of the reinforcing blade member itself strengthens the seal-like member even after application, stabilizes its shape, and applies a uniform pressure to the developing brush on the developing roller in the longitudinal direction thereof. Can be brought into soft contact effectively.

Further, in each of the above embodiments, the photosensitive drum D is used as the latent image carrier, but a photosensitive belt may be applied as the latent image carrier.

[0062]

As described above, by making the curved portion of the seal member which is flexible and has low frictional resistance softly contact the surface of the developing brush on the developing roller, poor standing of the developing brush and the longitudinal direction can be prevented. It is possible to form a stable image by eliminating image unevenness without causing adverse effects such as uneven supply of the developer. In addition, the developer adhering to the seal member is scraped off by the rubbing of the developing brush ears to prevent the accumulation of the developer, thereby preventing the developer from dropping, thereby effectively preventing poor image quality and contamination of internal components. Can be done. Further, the developer adhering to the seal-like member is scraped off by the ears of the developing brush, so that maintenance for periodically removing the developer can be eliminated.

On the other hand, the curved portion of the seal member is brought into soft contact with the developer on the latent image carrier and the developer on the developing roller, so that the surface of the latent image carrier is sealed while developing. It is possible to form a stable image by eliminating image unevenness due to adverse effects such as poor brushing of the brush and uneven supply of the developer in the longitudinal direction. Moreover,
The developer adhering on the seal-like member is scraped off by the ears of the developing brush to prevent the accumulation of the developer, and to prevent the developer from dropping from the latent image carrier onto the paper or the transfer belt, thereby reducing the image quality. It is possible to effectively prevent contamination of the in-machine parts.

In particular, by attaching at least one of both long side edges of the seal member together with a reinforcing member for reinforcing the long side of the seal member to the longitudinal edge of the opening, it is flexible and frictional. The shape of the sealing member made of a material having low resistance can be stabilized by the strength of the reinforcing member itself, and the sealing member can be stuck smoothly without waving or distortion at the time of sticking. In addition, the strength of the reinforcing member itself stabilizes the shape of the long side of the seal member even after sticking, and the seal member can be in soft contact with the surface of the developing roller while applying uniform pressure in the longitudinal direction thereof. As a result, stable performance of the developing device can be exhibited.

On the other hand, the annular abdomen of the annular section of the seal member is brought into soft contact with the developer in the developer flow path, so that the seal member is gently and gently pressed against the developing brush, and the soft contact with the developing roller is stabilized. You can do it. Moreover,
At the time of sticking the seal-like member, the seal-like member having an annular cross section can be easily handled, and the mounting workability can be improved.

In particular, by forming the seal-like member in a substantially circular cross section or a substantially semi-circular cross-section, the antinode of the seal-like member is brought into line contact with the developing brush on the developing roller, and is softly contacted with the developing roller. Can be performed more stably.

On the other hand, by filling the inside of the seal-like member with the elastic foam, the abdomen of the seal-like member is always brought into contact with the developing brush on the developing roller with a stable contact pressure, and the developing roller is stabilized. Soft contact can be made effectively.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a developing device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the vicinity of a developing roller.

FIG. 3 is a cross-sectional view of the vicinity of the seal member.

FIG. 4 is an explanatory diagram showing an experimental result comparing performance with a comparative example.

FIG. 5 is a cross-sectional view around a developing roller according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view of the vicinity of the seal member.

FIG. 7 is an explanatory diagram showing an experimental result of comparing performance with a comparative example.

FIG. 8 is a cross-sectional view around a developing roller according to a third embodiment of the present invention.

FIG. 9 is a cross-sectional view of the vicinity of the seal member.

FIG. 10 is an explanatory view showing an experimental result of comparing performance with a comparative example.

FIG. 11 is a cross-sectional view around a developing roller according to another embodiment of the present invention.

FIG. 12 is a cross-sectional view showing the vicinity of the seal member.

FIG. 13 is a cross-sectional view around a developing roller according to a conventional example.

FIG. 14 is a sectional view showing the vicinity of a developing roller according to another conventional example.

FIG. 15 is a cross-sectional view of the vicinity of a developing roller according to another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Developing tank (frame) 10 Seal material 11 Opening 12 Spike height regulating blade (layer thickness regulating member) 18 Frame (frame) 19 Toner flow path (developer flow path) 2 Developing roller 6, 7, 8, 9 Seal Member 62, 72 Reinforcement blade member (reinforcement member) D Photoconductor drum (latent image carrier) X Developing device

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tomohiko Kimura 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Europe 22-22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka F-term (for reference) 2H077 AA12 AA14 AD06 AD13 AD22 BA08 CA12

Claims (6)

[Claims] An opening portion of a frame provided at a portion opposed to a latent image carrier for carrying and transporting the electrostatic latent image, and opening in a width direction orthogonal to a transport direction of the latent image carrier; The developer is provided so as to face the surface of the latent image carrier with the opening interposed therebetween, and the developer held on the surface is caused to act on the electrostatic latent image with its own rotation, thereby causing the developer on the surface of the latent image carrier to rotate. A developing roller that develops an image; a layer thickness regulating member provided upstream of the opening in the rotation direction of the developing roller to regulate a layer thickness of the developer held by the developing roller; and a layer thickness of the developing roller. A developer flow path that is covered from outside by a frame between corresponding portions corresponding to the regulating member and the opening, and a developer flow path provided downstream of the opening in a conveying direction of the latent image carrier; And a sealing material that comes in contact with A flexible and low-frictional material that is provided over the width direction of the developing roller at the periphery of the opening to be formed and that makes a curved portion protruding toward the developer flow path softly contact the developer on the developing roller. And a sealing member comprising: 2. An opening of a frame provided at a portion facing a latent image carrier for carrying and transporting the electrostatic latent image, and opening in a width direction orthogonal to a transport direction of the latent image carrier. The developer is provided so as to face the surface of the latent image carrier with the opening interposed therebetween, and the developer held on the surface is caused to act on the electrostatic latent image with its own rotation, thereby causing the developer on the surface of the latent image carrier to rotate. A developing roller that develops an image; a layer thickness regulating member provided upstream of the opening in the rotation direction of the developing roller to regulate a layer thickness of the developer held by the developing roller; and a layer thickness of the developing roller. A developer flow path covered from outside by a frame between corresponding portions corresponding to the restricting member and the opening, and a width direction of the developing roller at a position upstream of the opening in a rotational direction of the developing roller. Provided and protrudes toward the developer flow path side. Developing apparatus is characterized by comprising a seal member made of a flexible and low frictional resistance material such as to respectively soft contact to the developer on the latent image bearing member and developing roller tracks section. 3. A long-side edge of at least one of the long sides of the seal member is attached to a longitudinal edge of the opening together with a reinforcing member for reinforcing the long side of the seal member. The developing device according to claim 1 or 2, wherein 4. An opening provided in a portion facing a latent image carrier for carrying and transporting an electrostatic latent image, and opening in a width direction orthogonal to a direction in which the latent image carrier is transported, The developer is provided so as to oppose the surface of the latent image carrier, and the developer held on the surface acts on the electrostatic latent image with its own rotation to develop an image on the surface of the latent image carrier. And a layer thickness regulating member provided upstream of the opening in the rotation direction of the developing roller to regulate the layer thickness of the developer held by the developing roller; and a layer thickness regulating member of the developing roller. A developer flow path partitioned by a frame between corresponding portions corresponding to the openings, and a seal member provided downstream of the opening in the conveying direction of the latent image carrier and in contact with the latent image carrier. And an opening located on the upstream side in the rotation direction of the developing roller. A flexible and low-frictional material that is provided at the edge of the developing roller in the width direction of the developing roller and that makes an abdominal portion having an annular cross section projecting toward the developer flow path softly contact the developer in the developer flow path. And a sealing member comprising: 5. The developing device according to claim 4, wherein said seal-like member is formed in a substantially circular cross section or a substantially semicircular cross section. 6. The developing device according to claim 4, wherein the inside of the seal member is filled with an elastic foam.