JP3472961B2 - Developing device for image forming machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic copying machine,
Applied to image forming machines such as the printer and facsimile
Developing device for developing an electrostatic latent image into a toner image, more specifically
Are projecting walls extending inward from both side walls of the developing housing
A seal member is disposed on each of the arc-shaped surfaces of the
The lower semicircle of each peripheral surface of the non-development working area of the member is
Is configured to be pressed against the surface of the corresponding seal member.
And a developing device of the image forming machine. [0002] 2. Description of the Related Art In an image forming machine such as an electrostatic copying machine,
Forms an electrostatic latent image on the surface of the photoreceptor drum, and then
The electrostatic latent image is developed into a toner image by an image device, and the toner image is developed.
An image forming process of transferring the image onto a transfer paper such as a normal paper is performed.
You. The developing device includes a developing housing having both side walls and a front end wall.
Between the front ends of the side walls in the developing housing.
Supported to apply the developer to the peripheral surface of the photosensitive drum.
And a developer application means. Developer application means
Is disposed within the sleeve member and the sleeve member.
And a stationary magnet member. Magnet member is sleeve part
It extends through the material in its axial direction, but its axial length is three.
It is formed shorter than the axial length of the valve member. sleeve
On the peripheral surface of the member, there is a magnet member inside, so
Axial direction where a considerable magnetic field (ie magnetic attraction) exists
There is no magnet member inside the developing work area in the center and inside,
Therefore, the magnetic field (ie, magnetic attraction) is extremely small.
And non-developing work areas at both ends in the axial direction.
The sleeve member is made of non-magnetic material such as aluminum.
ing. The developing work area on the peripheral surface of the sleeve member
Sandblasting to improve the transferability of the image agent
Is applied to form an uneven surface.
Each of the non-developing work areas on the surface is formed as a smooth surface.
Projections extending inward in the axial direction are formed on both side walls of the developing housing.
An exit wall is formed. Each of the projecting walls is a sleeve member
The lower semicircle of the peripheral surface in the corresponding non-developing work area
The front end extends inside the front end wall with a gap along
Has an arc-shaped surface connected to the Each of arc-shaped surfaces
In each case, a seal member for preventing the developer from scattering is provided.
You. Below the peripheral surface of each of the non-developing working areas of the sleeve member
The semicircle is pressed against the surface of the corresponding sealing member.
You. A rectangular sheet extending in the longitudinal direction with a predetermined width
Each of the tool members is placed on the corresponding arc-shaped surface.
, One end of each of the seal members is
Positioned upstream in the rotation direction, one of the side edges is
Positioned to extend along the axially outer edge of the development work area
Attached. One end of each of the sealing members is a sleeve portion.
It extends linearly in the axial direction perpendicular to the rotation direction of the material.
The upstream side. [0003] SUMMARY OF THE INVENTION The above conventional developing device
As described above, the current value of the peripheral surface of the sleeve member is changed.
Concavo-convex surface formed by sandblasting in image working area
During the developing operation, the developer has a considerable magnetic field.
On the peripheral surface where the uneven surface is formed
Non-developing work area carried and transported, and the magnetic field is extremely small
Are transported on the peripheral surfaces of both ends consisting of smooth surfaces.
Desirably not. However, the development work area
Transported along the border with each of the non-developing work areas
Some of the developer after development may cross the boundary and
It slightly protruded into each of the areas, and this protruded
The developer is released to the smooth surface side of each of the non-development work areas.
And each one of the seal members is conveyed on the smooth surface.
It is left on the end face. Or developer that has overflowed
Interferes with the one end of each of the seal members and is on the one end surface.
It will be left. By repeating the development process,
The amount of developer stored at one end of each of the
To be increased. And finally the development housing
The upper end at both ends of the front end wall and the peripheral surface of the photosensitive drum
Is scattered outside the developing housing through the gap between
Is dropped on both ends of the transfer paper
May be a factor of In addition, both transfer paper
Developer that has fallen on the end surface adheres to the peripheral surface of the photosensitive drum
The cleaning blades at both ends.
The edge may be damaged. Furthermore, during transportation
The developer that has fallen on both end surfaces of the transfer paper is located at the center of the transfer paper.
When it sticks out to the peripheral surface of the photoconductor drum
May damage the photoconductor. An object of the present invention is to provide a three-dimensional developer application means.
Non-developing work areas formed at both ends of the peripheral surface of the
Prevents the developer from scattering outside the developing housing
Developing a new image forming machine
To provide. [0005] Another object of the present invention is to provide a developer application means.
Non-development work area formed at both ends of the peripheral surface of the leave member
To efficiently return the developer transported to the development area to the development work area
To provide a new image forming machine developing device that enables
That is. [0006] Still another object of the present invention is to provide a developer applying means.
Non-development work formed at both ends of the peripheral surface of the sleeve member
Conveyed to one end face on the upstream side of the seal member that seals the work area
The developer to the developing work area efficiently.
To provide a developing device for a new image forming machine.
You. [0007] According to the present invention, both side walls are provided.
And a developing housing having a front end wall, and inside the housing.
At the front end of both side walls
Means for applying a developer to the peripheral surface.
The developer applying means includes a cylindrical sleeve member and the sleeve.
A stationary magnet member disposed within the probe member.
The member extends axially within the sleeve member but is
The axial length is shorter than the axial length of the sleeve member,
The sleeve member is a developing work area in which the magnet member is present.
Of both ends in the axial direction where the magnet member does not exist in the region and inside
Having an image working area, and extending inward in the axial direction on both side walls.
Protruding walls are formed, each of the protruding walls being the sleeve member.
Of the peripheral surface in the corresponding non-developing work area,
A front end wall extending at a gap along the lower semicircle and having a front end wall
Has an arc-shaped surface connected to the inner surface of the
Each is provided with a sealing member, and the non-display of the sleeve member is provided.
Substantially the lower semicircle of each peripheral surface of the image working area corresponds
Is pressed against the surface of the sealing member to be
One end is positioned upstream of the sleeve member in the rotational direction.
One of each side edge is the axially outer edge of the development work area.
Of an image forming machine positioned to extend along a line
In the apparatus, the one end of each of the sealing members is in the axial direction.
Developing from outside toward downstream in the rotational direction of the sleeve member
Extends close to the working area and contacts the corresponding side edge.
Sloping partAnd the magnet member is a photosensitive drum.
Main pole located at the circumferential position closest to the peripheral surface of
And a transfer arranged at an interval downstream of the main pole.
And a corresponding one of the inclined portions of the seal member.
The downstream end of the slope that intersects the side edge is the slot of the transport pole.
Within the range of the magnetic field acting on the peripheral surface of the
At least from the circumferential position where the magnetic force is strongest
Orientation position,Picture characterized by the fact that
A developing device for an image forming machine is provided. [0008] [0009] BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described.
Preferred embodiments of the developing device of the image forming machine are described with reference to the attached drawings.
I will explain. FIG. 1 shows the structure of the image forming unit 100.
Is schematically shown. The image forming unit 100
Developing device 2, photosensitive drum 4, cleaning device 6, belt
And an electric copying machine (not shown).
Be worn. The image forming unit 100 is mounted on the electrostatic copying machine
In this state, the photosensitive drum 4 is driven by driving means (not shown).
Is driven clockwise in FIG. 1 and charged
Peripheral surface of photosensitive drum 4 uniformly charged by device 8
In addition, the image is exposed by an appropriate method known per se.
To form an electrostatic latent image. This electrostatic latent image is
Then, the toner image is developed by the developing device 2. This Tona
-The image is transferred to a sheet member such as plain paper in the transfer area.
After the image is fixed by a fixing device (not shown),
You can get a picture. Residual toner on the peripheral surface of the photosensitive drum 4
Is the cleaning device 6 in the cleaning area.
Is scraped off by the cleaning blade 6a and the toner is collected.
Spiral member 6b makes toner collection container not shown
Discharged and collected. Referring to FIG. 1 to FIG. 3, the developing device 2
A housing 10 is provided. For example, appropriate
Developing housing that can be integrally molded from synthetic resin
The bottom wall 12 and the front edge of the bottom wall 12 in the longitudinal direction.
A front wall 14 extending upward and a longitudinal rear edge of the bottom wall 12
Rear wall 16 extending upwardly from the front end of the bottom wall 12 in the width direction.
From the front wall 14 and the front end of the rear wall 16.
From the continuous front end wall 17 and the width direction rear end of the bottom wall 12
It extends upward and is connected to the rear ends of the front side wall 14 and the rear side wall 16.
And a rear end wall 18 that is provided. In this specification,
The longitudinal direction of the developing housing 10 is shown in FIG.
Indicates the front and back sides of the paper surface, and the front or front in the longitudinal direction.
Is the direction toward the front side or the front side of the paper in FIG.
The term “rear side” or “rear side” in the longitudinal direction refers to paper in FIG.
It indicates the direction to the back side or the back side of the surface. Ma
The width direction of the developing housing 10 is the left direction in FIG.
The right direction is shown, and the front or front in the width direction is shown in FIG.
Indicates the direction to the left or left, and
The rear of the chair means the direction from right to right in FIG.
Shall be shown. The same applies to other figures
And The bottom wall 12 of the developing housing 6 has a bottom wall 1
2 and extends longitudinally at a predetermined height
Partition wall 19 is integrally formed. Longitudinal direction of partition wall 19
Between the front end and the front side wall 14 and the longitudinal direction of the partition wall 19.
A developer transfer opening is provided between the rear end and the rear side wall 16.
Are defined. Development housing
A developer applying means 20 is provided at the forefront of the cartridge 10 in the width direction.
Have been. The developer applying means 20 is substantially horizontally extended in the longitudinal direction.
The cylindrical sleeve member 22 and the cylindrical three
From the stationary permanent magnet member 24 disposed in the
It is configured. In the following description, “Three
The term “bub member 22” is an abbreviation for the cylindrical sleeve member 22.
And the “magnet member 24” refers to the stationary permanent magnet member 24.
It is an abbreviation. The sleeve member 22 is made of non-magnetic material such as aluminum.
The magnet member 24 is made of a conductive material and is rotatable.
Is fixed at a predetermined angular position. For the sleeve member 22
Has a fixed rotating shaft (not shown),
By means of rotation in FIG.
It is. Incidentally, the front side wall 14 and the rear side wall of the developing housing 10 are provided.
Between the sleeve member 22 and the peripheral surface of the sleeve member 22
An ear cutting plate 26 is arranged in parallel. This hotplate 26
Is held on the peripheral surface of the sleeve member 22 and
Regulates the amount of developer transported to the printer. The developer is agitated and transported behind the developer applying means 20.
A transport mechanism is provided. The developer stirring and transport mechanism
A stirring and conveying member 30 comprising a rotating shaft and a spiral blade, respectively;
32, a stirring and conveying member 34 including a rotating shaft and a plurality of plate blades
And The stirring and conveying members 30 and 32 are
Arranged on both sides in the width direction with the partition wall 19 of the housing 10 interposed therebetween
And each extends longitudinally along the bottom wall 12.
Rotatably supported between the front side wall 14 and the rear side wall 16.
ing. The stirring and conveying member 30 is driven by a driving unit (not shown).
1 is rotated counterclockwise in FIG.
Is transported from the front to the back in the longitudinal direction while stirring
You. The stirring and conveying member 32 is driven by a driving unit (not shown).
1 to rotate clockwise to stir the developer
While transporting from the rear side to the front side in the longitudinal direction. did
Consequently, the developer is applied to both sides of the partition 19 and the partition 1
9 and the corresponding front side wall 14 and the rear side.
Between a developer transfer opening formed with the side wall 16
Is circulated and transported while being stirred. Contained in developer
Toner is triboelectrically charged. The stirring and conveying member 34 is connected to the stirring and conveying member 32.
Between the developer applying means 20 and the bottom wall 12
Between the front side wall 14 and the rear side wall 16 so as to extend in the longitudinal direction
It is supported rotatably. In the stirring and conveying member 34
In the central area in the axial direction of the rotating shaft, there is an interval in the circumferential direction.
And a plurality of radially outwardly extending plate blades are formed.
Spiral blades are formed in both end regions of the turning shaft, and the center region is formed.
Radially outward in the intermediate region between the region and the two end regions
One extending plate blade is formed. The central area is
Image formation on sleeve member 22 and photosensitive drum 4
Corresponding to the region. The stirring and conveying member 3 configured as described above
Reference numeral 4 denotes a counterclockwise direction in FIG.
It is driven to rotate in the direction. Central area of the stirring and conveying member 34
The plurality of plate blades arranged in the region
Downstream of the position facing the photosensitive drum 4 in the rotational direction
When the existing developer is conveyed to the stirring / conveying member 32 side,
Then, the developer on the stirring / conveying member 32 side is
On the upstream side in the rotation direction from the position facing the cutting board 26
Transport. Further, it is arranged at both end regions of the stirring conveying member 34.
The spiral blades exist in both end regions of the stirring and conveying member 34.
Move the developer toward the inside in the axial direction, and
The plate blades arranged separately are moved by the spiral blades.
The developer acts to return the developer to the stirring and conveying member 34. In the developing housing 10 of the developing device 2,
Front ends of the front side wall 14 and the rear side wall 16 in the width direction.
Parts 14A and 16A extend in a direction approaching each other
And extends upward from the upper end surface at the rear in the width direction.
It is configured to issue. Front wall 14 and rear wall 16
Of the front ends 14A and 16A in the width direction.
The rear end in the width direction is from the upper end surfaces of the front side wall 14 and the rear side wall 16.
It is formed so as to form an upright wall. The above
The front end plate 14 of the front side wall 14 and the rear side wall 16
A is arranged to extend between A and 16A. Also,
Upper end surfaces of the front side wall 14 and the rear side wall 16,
Behind the upright wall formed at the rear end of 4A and 16A
Formed by the region and the upper end surface of the rear end wall 18
At the upper end opening of the housing 10, a developer container 36 is provided.
Is attached so as to cover the opening. Developer storage container
A start developer is stored in 36. Developer storage container
36 is a container body having a developer outlet at the lower end,
An annular flange extending outward from the periphery of the outlet, and a container
It is detachably mounted on the lower surface of the main body and closes the discharge port
A seal film member. Seal film section
The material is on the bottom surface from the front to the back in the longitudinal direction of the container body.
The seal part that is detachably mounted on the
An inversion polymerization section which inverts at the rear side and reaches the front side,
It is composed of the joint and the peeling grip formed continuously.
Has been established. Before using the image forming machine for the first time,
Peel off the seal against the bottom of the container body
When pulled in the longitudinal direction, which is the
Is pulled forward relative to the
The film member has its seal part peeled off and the outlet is opened.
It is. The developer contained in the container main body has the discharge port and
Developing housing through an upper end opening of the developing housing 10
Drop 10 into the box 10. FIG. 1 shows a developer container 3
6. All the developer in the container body is in the developing housing 10.
This shows a state where the sheet is discharged and used for development. What
In the developing device 2 according to the embodiment, the magnetic carrier
A developer consisting of toner and toner is used.
Other embodiments using only developer
I do. The both side walls of the developing housing 10, that is, the front side
The axial direction of the sleeve member 22 is provided on the side wall 14 and the rear side wall 16.
The front protruding wall 14B and the rear protruding wall 16B extending inwardly
Is formed. To the front protruding wall 14B and the rear protruding wall 16B
Are arcuate surfaces 14C and 16C which are substantially semicircular.
Are formed. Constant width (axial direction of sleeve member 22)
Arc-shaped surface 14C extending with a width in the
The front end of 16C (the front end in the width direction) is
It is connected to the inner surface of the front end wall 17 of the jing 10. The magnet member 24 of the developer applying means 20
Extends in the sleeve member 22 in its axial direction.
Is shorter than the axial length of the sleeve member 22.
(Not shown). Referring to FIGS. 4 and 5,
The magnet member 2 is provided inside the peripheral surface of the sleeve member 22.
4 are present and therefore a considerable magnetic field (ie magnetic attraction)
Force) is present in the developing work area 40 at the axial center,
There is no magnet member 24 in the part, and therefore the magnetic field (ie,
Non-development at both ends in the axial direction with extremely low magnetic attraction
A work area 42 is formed. The circumference of the sleeve member 22
In the development work area 40 on the surface, the developer transportability is improved.
Is subjected to sand blasting to form an uneven surface
Have been. In addition, the non-developing work on the peripheral surface of the sleeve member 22 is performed.
Each of the work areas 42 is formed on a smooth surface. Front protruding wall
14B and the arc-shaped surface 14C of the rear protruding wall 16B and
16C is the corresponding non-development work area of the sleeve member 22.
Substantially along the lower semicircular portion of the peripheral surface in region 42
Are positioned so as to extend with a gap of. arc
The widths of the shape surfaces 14C and 16C correspond to the corresponding non-developing work areas.
42 is substantially the same as the axial width. On the arc-shaped surfaces 14C and 16C, a developer
A seal member 50 for preventing scattering is provided. Non-woven
Appropriate materials such as cloth, acrylic resin, Teflon (trade name)
Each of the seal members 50 that can be formed from FIG.
Has a constant thickness as a whole as shown in 7
Each have a long, narrow band shape,
Side edges that run parallel and straight in the longitudinal direction and are short in length
52 and the long side edge 54 and the long side edge 54
Linearly inclined toward the short side edge 52
One end in the longitudinal direction of the inclined portion 56 and the side edge 52
Between each of the side edges 52 and 54 at right angles to each of the side edges 52 and 54.
And the other longitudinal end 58 extending linearly.
You. Each width of the seal member 50 is equal to the arc-shaped surface 14C.
And 16C, and therefore the non-development operation of the sleeve member 22.
The width is substantially the same as the width of each of the work areas 42.
Each of the sealing members 50 configured as described above
To the arc-shaped surfaces 14C and 16C through an appropriate adhesive.
Is attached. Non-developing work area 42 of sleeve member 22
Substantially the lower semicircle of each peripheral surface of the corresponding seal
The surface of the member 50 is pressed and sealed. Seal member
Each of the non-developing working areas 42 of the sleeve member 22
It is arranged to be pressed against the smooth peripheral surface
As a result, the sealing performance is improved, and the wear of each of the sealing members 50 is reduced.
Is prevented. Each of the sealing members 50 has a corresponding arc shape.
In the state of being adhered to the surface 14C and 16C, respectively
The inclined portion 56 which is one end in the longitudinal direction of the sleeve member 2
2 is located on the upstream side in the rotation direction and has a short side edge 5.
2 extends along the axially outer edge of the development work area 40
It is positioned as follows. Therefore, each of the seal members 50
Are affixed to the corresponding arc-shaped surfaces 14C and 16C.
In this state, one end of each of the seal members 50 is
The rotation of the sleeve member 22 from the axially outside of the leave member 22
So as to approach the developing work area 40 in the downstream direction.
Extending from the slope 56 intersecting the corresponding side edge 52.
It can be said that it has been done. Referring to FIG. 4 (a) and FIG.
24 is a circumferential direction closest to the peripheral surface of the photosensitive drum 4
The main pole N1 arranged at the position and a sleeve for the main pole N1
A transporter arranged at an interval downstream of the member 22 in the rotation direction.
A transmission pole S2 (a transport pole S2 on the downstream side with respect to the main pole N1);
A slot arranged at an interval downstream of the transport pole S2.
The developer peeling pole S3 on the sleeve member 22 and the sleeve member
22 on the downstream side of the developer stripping pole S3
The upstream side of the developer regulating member (spike plate 26)
Upstream of the developer regulating member
An interval is provided between the transmission pole N2 and the downstream side of the upstream transport pole N2.
And at an interval upstream of the main pole N1
And a downstream transport pole S1 of the developer regulating member.
I have. The main pole N1 causes the developer to have a spike phenomenon as required
To achieve the desired development action
The transport pole S2 is a magnetic pole, and the developer after development is
A magnetic pole for drawing into the developing housing 10
You. The developer peeling pole S3 on the sleeve member 22 is pulled in.
The developer on the sleeve member 22 is applied to the developing housing 1.
Magnetic pole for peeling as required within 0
The upstream transport pole N2 of the developer regulating member is
An appropriate amount of the developer is held on the sleeve member 22.
For transporting the developer regulating member downstream
The pole S1 is provided with the developer held on the sleeve member 22.
The gap between the peripheral surface of the sleeve member 22 and the cutting board 26 is
These are magnetic poles that allow the gas to pass smoothly. These poles
By using well-known sequence and function itself
Good. In FIG. 6, curves n1, s2, s3, n
2 and s1 are the normal directions of the magnetic poles (of the sleeve member 22).
(In the direction perpendicular to the axis).
You. Referring to FIG. 4 and FIG.
50 at the corresponding side edge 52 of each ramp 56.
The downstream end of the inclined portion 56 (the rotation direction of the sleeve member 22).
Downstream end) is the sleeve member 22 of the transport pole S2.
Within the magnetic field acting on the peripheral surface of
From the circumferential position where the magnetic force is strongest to the circumferential position on the downstream side
It is important to be positioned in between. In the embodiment
As shown in FIG.
Of the inclined portion 56 intersecting the corresponding side edge 52 of the portion 56
The downstream end is the circumferential surface of the sleeve member 22 of the transport pole S2.
Within the range of the magnetic field acting on the surface and the strongest magnetic force
Directional position. The front side wall 14 and the rear side of the developing housing 10
Side plates 60 are mounted on the outside of the wall 16 respectively.
(Only one side plate 60 is shown in FIG. 1). Feeling
The optical drum 4 rotates around each of the side plates 60 via a bearing member.
Rollably supported. The photosensitive drum 4 is a sleeve
The axial length is formed longer than the member 22,
Excluding the non-image forming areas at both ends of the body drum 4 in the axial direction
The image forming area in the center is located on the peripheral surface of the sleeve member 22.
Then, it is positioned with a predetermined gap. In addition,
At the foremost end of the front side wall 14 and the rear side wall 16 of the housing 10
An arc-shaped surface is formed at the upper end of the
In each case, the peripheral surfaces at both ends of the photosensitive drum 4 are pressed against each other.
A side seal member is provided (not shown).
Further, the cleaning device 6 and the charger 8 are connected to the side plate 60.
Are arranged between each of them. As shown in FIG. 1 and FIG.
As shown, the front end 1 of the front side wall 14 and the rear side wall 16
Between the upper end portions at the rear positions of the foremost end portions of 4A and 16A
(In the embodiment, between the top ends)
Are arranged. The upper seal body 62 is a sheet-shaped upper seal.
The lock member 62a is provided. Width of upper seal member 62a
The front end portion is the entire area in the axial direction between both end portions of the photosensitive drum 4.
Firmly against the peripheral surface of the
The seal at the front end in the width direction of the upper opening of the jing 10 is sufficient.
It will be done in minutes. The cutting board 2 of the developing housing 10
6 is covered with an upper seal body 62.
You. Image forming unit 1 including the developing device 2
00 is detachably mounted on a copying machine (not shown) and used.
It is. Hereinafter, the operation of the developing device 2 will be summarized and described. Figure
1 and FIG. 4, photosensitive drum 4, developing housing
Agitating and conveying members 30, 32 and 34 in the
In FIG. 1, each of the probe members 22
It is driven to rotate. Developer in developing housing 10
Is controlled by the stirring and conveying members 30 and 32 as described above.
The developer is stirred and circulated, and a part of the developer is stirred and transported.
The toner is returned to the stirring and conveying member 32 by the feeding member 34, and
Another part of the agent is the
Conveyed to the upstream area. A part of the developer is supplied to the magnet member 24.
The action of the N2 pole magnetic field at
It is an appropriate amount for the peripheral surface of the sleeve member 22 in the upstream region.
It is pumped and held. The circumference of the sleeve member 22
The developer pumped to the surface is rotated by the sleeve member 22.
Counterclockwise direction indicated by an arrow in FIGS.
Transported to At this time, by the action of the cutting board 26,
Excess developer is removed from the peripheral surface of the sleeve member 22.
You. Peripheral surface of photosensitive drum 4 and peripheral table of sleeve member 22
In the development area, which is the area closest to the surface,
Develops on the electrostatic latent image formed on the peripheral surface of the body drum 4
The toner in the agent is selectively adhered, and the electrostatic latent image
Is developed into a toner image. Retained on the peripheral surface of sleeve member 22
The developed developer is located downstream of the development zone.
As a result, the developing housing 1
0, and further in the downstream area, the above S3
By the action of the pole magnetic field, from the peripheral surface of the sleeve member 22
Peeled off. Detached from the peripheral surface of the sleeve member 22
The mixed developer is mixed with the developer in the developing housing 10.
You. Thus, the developing operation is continued. Referring to FIG. 4 to FIG.
During the developing operation, the peripheral surface of the sleeve member 22
The boundary between the developing work area 40 and each of the non-developing work areas 42
A part of the developer after the development is transported along the boundary,
Slightly out of each of the non-developing work areas 42 beyond the
The protruding developer is transferred to the non-development work area 4.
2 is separated to the smooth surface side and transported on the smooth surface
And on one end surface of each of the seal members 50 (sleeve member
22 on one end face on the upstream side in the rotation direction
And Alternatively, the protruding developer is applied to the seal member 50.
Each of which interferes with the one end face and is left on the one end face
To try. However, in the present invention,
As such, one end of each of the seal members 50 is
From the outside in the axial direction of the member 22 in the rotational direction of the sleeve member 22
Extending toward the working area 40 toward the flow
To the corresponding side edge 52 (axially outside of the developing work area 40).
Side edge 52) positioned to extend along the edge
The sleeve 56
The sealing member 5 extends along the smooth surfaces at both axial ends of the member 22.
The developer transported to each of the inclined portions 56 is a sleeve portion.
In the axial direction of the developing work area 40 accompanying the rotation of the material 22
It is drawn toward the outer edge and stays on the slope 56.
Is reliably prevented. The magnet member 24 is provided on the peripheral surface of the photosensitive drum 4.
Main pole N1 disposed at a circumferential position closest to
Spaced on the downstream side in the rotation direction of the sleeve member 22 with respect to the pole N1
And a transport pole S2 arranged at a distance.
0 of each inclined portion 56 at the corresponding side edge 52.
The downstream end of the inclined portion 56 is the sleeve portion of the transport pole S2.
Within the range of the magnetic field acting on the peripheral surface of
At least from the circumferential position where the magnetic force is strongest to the downstream circumferential direction
If configured to be positioned between
Seal along the smooth surfaces at both ends in the axial direction of the leave member 22
The developer carried to each inclined portion 56 of the member 50 is transported.
Due to the magnetic attraction of the pole S2, the sleeve member 2
2 in the axial direction outside of the developing work area 40 accompanying the rotation operation
More efficiently and effectively retracted and sloped towards the edge
Stagnation in the portion 56 is more reliably prevented. In addition,
Departure from the development work area 40 to each of the non-development work areas 42
The drawn-in developer is drawn into the developing work area 40.
The corresponding side edge 5 of each inclined portion 56 of the
2 and the downstream end of the inclined portion 56 is the
Within the range of the magnetic field acting on the peripheral surface of the leave member 22.
So that it can be positioned at the circumferential position where the magnetic force is strongest.
It has the greatest effect when it is formed,
Within the range, it is downstream from the circumferential position where the magnetic force is strongest.
The above-mentioned retraction is effective even if the
Will be The developing device 2 according to the present invention is as described above.
It is configured and performs the above-mentioned actions,
Non-development of both ends in the axial direction on the peripheral surface of the leave member 22
Even if the developer is transported to the work area 42,
Reliably drawn into the developing work area 40 and retained
Therefore, both the front end wall 17 of the developing housing 10 and the
The gap between the upper end at the end and the peripheral surface of the photosensitive drum 4
It is certain that it will scatter to the outside of the developing housing 10 from between
Is prevented. As a result, the developer
Dropping on both end faces, the cause of so-called carrier fireflies
There is no risk of becoming. In addition, the developer
Drops on both end surfaces and adheres to the peripheral surface of the photosensitive drum 4
Damaged edges at both ends of cleaning blade
There is no danger of doing so. Furthermore, when the developer is being transported,
It falls on both end surfaces of the transfer paper, and
There is no danger of damage to the photoconductor due to adhesion. FIG. 8 shows another example of the seal member 50.
An embodiment is shown. The sealing member 50 shown in FIG.
The difference from the seal member 50 shown in FIG.
56 is formed over the entire area of one end in the longitudinal direction
Instead, the inclined portion 56 is formed leaving a portion 59.
The other configuration is substantially the same. part
The minute 59 has a shorter length, perpendicular to the longer side edge 54.
It is formed so as to extend a predetermined length in the direction of the side edge 52.
You. The length of the portion 59 may be formed relatively small.
preferable. As a result, when the developer is accumulated in a part 59,
Even so, it is not enough to scatter outside,
Due to the presence of the inclined portion 56, substantially the same as in the previous embodiment
Above, the same function and effect can be achieved. FIG.
As shown in (a), each of the sealing members 50
Of the sleeve member 22 on the upstream side in the rotation direction
Arc shape formed on front protruding wall 14B and rear protruding wall 16B
Located in the vicinity of the upstream end in the rotational direction of the convex surfaces 14C and 16C.
The upper end inside the front end wall 17 or the upper end
Each of the sealing members 50 is positioned so that
There is another embodiment in which the length of the one end is extended (FIG. 4).
A virtual extension part y shown by a two-dot chain line in FIG.
See). In the case of this embodiment, each of the seal members 50
The inner surface on the one end side (in FIG. 4, inside the virtual extension portion y)
Surface) and the smooth surfaces at both axial ends of the sleeve member 22.
There is a possibility that a gap is formed between the developer and the developer stays
However, the inclined portion 56 is formed in each of the seal members 50.
So that when it accumulates to some extent, the downstream end side of the inclined portion 56
Is likely to be discharged from the
The more the developer scatters outside the housing 10, the more the developer stays
Never. [0027] According to the developing device of the image forming machine according to the present invention,
If so, both ends of the peripheral surface of the sleeve member of the developer applying means
Outside the developing housing from the non-developing working area
It is possible to reliably prevent the developer from being scattered into the developer.
Further, both ends of the peripheral surface of the sleeve member of the developer applying means
The developer transported to the non-development work area
To efficiently return to the business domain. Furthermore,
Formed on both ends of the peripheral surface of the sleeve member of the developer application means
Upstream of the seal member that seals the undeveloped work area
Efficiently returns developer transported to one end to the development work area
Make it possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view showing an image forming unit provided with a developing device according to an embodiment of the present invention. FIG. 2 is a perspective view of a developing housing of a developing device provided in the image forming unit shown in FIG. 1 as viewed from a certain angle; FIG. 3 is a perspective view of the developing housing shown in FIG. 2 as viewed from a different angle from that of FIG. 2; FIG. 4A is an enlarged view of a main part of FIG. FIG. 4B is a schematic view of the main part of FIG. 4A viewed from the left in FIG. FIG. 5 is a schematic view of a main part of FIG. 4 (a) viewed from the upper left in FIG. 4 (a). FIG. 6 is a view for explaining a positional relationship between the seal member and the stationary permanent magnet member shown in FIGS. 4 and 5; FIG. 7 is a perspective view of the seal member shown in FIGS. 4 to 7; FIG. 8 is a perspective view showing another embodiment of the seal member. DESCRIPTION OF SYMBOLS 2 Developing device 4 Photoreceptor drum 10 Developing housing 14 Front side wall 14A Front end 14B Front protruding wall 16 Rear side wall 16A Front end 16B Rear protruding wall 20 Developer applying means 22 Cylindrical sleeve 24 Static permanent magnet member 40 Developing work area 42 Non-developing work area 50 Seal members 52, 54 Side edge 56 Inclined portion (one end in the longitudinal direction) N1 Main pole S2 Transport pole 100 Image forming unit

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tomohide Hozono 1-2-28 Tamazo, Chuo-ku, Osaka City Inside Kyose Lamita Co., Ltd. (72) Inventor Susumu Taniguchi 1-2-28 Tamaki, Chuo-ku, Osaka City Inside Kyose Lamita Co., Ltd. (72) Inventor Tetsuro Tomoe 1-2-2, Tamazo, Chuo-ku, Osaka City Inside Kyose Lamita Co., Ltd. (56) References JP-A 2000-206791 (JP, A) 153058 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 15/08 505 G03G 15/09

Claims (1)

(57) Claims: (1) A developing housing having both side walls and a front end wall, and a developing agent supported between front ends of both side walls in the housing to apply a developer to a peripheral surface of the photosensitive drum. Developer application means for applying, the developer application means including a cylindrical sleeve member, and a stationary magnet member disposed in the sleeve member, the magnet member passes through the sleeve member. The sleeve member extends in the axial direction, but has an axial length shorter than the axial length of the sleeve member. The sleeve member includes a developing work area in which the magnet member is present and axial ends in which the magnet member is not present. And a non-developing working area, wherein both side walls are formed with projecting walls extending inward in the axial direction, each of the projecting walls being substantially a peripheral surface of the sleeve member in a corresponding non-developing working area. Create a gap along the upper and lower semicircle Has an arc-shaped surface that extends vital front end is connected to the inner surface of the front end wall, the sealing member is disposed on the respective arc-shaped surface,
Substantially the lower semicircular portion of each peripheral surface of the non-developing working area of the sleeve member is pressed against the surface of the corresponding seal member, and one end of each of the seal members is located upstream of the sleeve member in the rotational direction. A developing device of the image forming machine, wherein one end of each side edge is positioned to extend along an axially outer edge of the developing work area, wherein one end of each of the seal members is positioned from the axially outer side. The sleeve member is configured to extend toward the developing work area toward the downstream side in the rotational direction of the sleeve member, and includes a slope portion that intersects the corresponding side edge, and the magnet member is closest to the peripheral surface of the photosensitive drum. A main pole disposed at a circumferential position, and a transport pole disposed at a distance downstream from the main pole, and intersects the corresponding side edge of each inclined portion of the seal member. The downstream end of the slope is the A magnetic field acting on the peripheral surface of the leave member and positioned between at least the circumferential position where the magnetic force is strongest and the circumferential position on the downstream side. apparatus.