JP3521683B2 - Image forming machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic copying machine,
Static electricity formed on the photosensitive layer of the photosensitive drum such as the printer
The latent image is developed into a toner image, and the toner image is transferred to transfer paper.
The present invention relates to an image forming apparatus for printing. 2. Description of the Related Art An image forming apparatus of this type is rotatably disposed.
Charge area, electrostatic latent image formation area, development area and transfer area
A photosensitive drum passing therethrough; and a photosensitive drum disposed in a charging area.
A charger that charges the peripheral surface of the ram to a specific polarity, and a
The peripheral surface of the photosensitive drum in the electrostatic latent image forming area
For developing an electrostatic latent image formed on a surface into a toner image
And is formed on the peripheral surface of the photosensitive drum disposed in the transfer area.
Transfer means for transferring the transferred toner image to transfer paper.
You. In such an image forming machine, the photosensitive drum
The drum rotates the photoreceptor drum to facilitate replacement.
The photoreceptor unit can be freely supported by the photoreceptor support means.
This photoconductor unit is equipped with an optical system unit.
It is configured to be detachably attached to the
Have been. [0003] As described above, the photoconductor unit
Configured to detachably attach the knit to the body frame
Image forming machine has a photoreceptor unit
Optical system in which the photoconductor drum is arranged on the body frame when
Must be positioned in a certain positional relationship to the unit
There is. Thus, the photosensitive drum is disposed on the body frame.
Position precisely to the specified optical unit
To ensure the accuracy of the photoreceptor unit as an assembly
And the assembly precision of this photoreceptor unit and body frame
Degree is required. [0004] The present invention has been made in view of the above facts.
Therefore, the main technical problem is the assembly of the photoconductor unit.
Standing accuracy and assembly accuracy with the machine frame are not necessary.
The photoreceptor unit can be mounted on the fuselage frame without
By attaching the photoconductor drum, it is possible to
To provide an image forming machine that can be positioned
You. [0005] The above-mentioned main technical problems are solved.
To achieve this, according to the present invention, there is provided a photosensitive drum and the photosensitive drum.
Photoreceptor unit comprising photoreceptor support means on which a photoreceptor drum is mounted.
The knit is attached to the body frame where the optical unit is
In the image forming machine detachably mounted, the photosensitive drum
Moves the drum body and the drum body at a predetermined position in the axial direction.
The photosensitive member supporting means rotatably supported in a state where
And a supporting shaft mounted on the
Equipped with a pair of shaft support portions that respectively support both ends of the support shaft,
The pair of shaft supports are formed so as to extend upward.
Contacting the lower end of the guide groove,
A fit formed subsequently and having a width corresponding to the diameter of the support shaft
A mating groove portion is provided, and the outer wall constituting the guide groove portion has an upper end.
A guide surface that slopes inward.
An image forming machine is provided. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention;
An embodiment of an image forming machine configured according to the present invention will be described in detail.
explain. In the illustrated embodiment, the present invention
Therefore, a printer is described as an example of the configured image forming machine.
I do. FIG. 1 shows a pre-processor constructed in accordance with the present invention.
One embodiment of the present invention is schematically illustrated. Printer 2
Is a mark such as a word processor in this embodiment.
Small and low-speed laser printers used as
The body housing 20 formed of a synthetic resin
Is provided. The body housing 20 is open at the top.
Open box-shaped housing body 21 and housing body
21 is pivotally mounted on a shaft 22 disposed above
And a cover 23. Aircraft constructed in this way
An airframe frame is provided on the housing body 21 of the housing 20.
3 is provided. Process on this body frame 3
The unit 4 is detachably mounted. The process unit 4 is provided as shown in FIG.
The photoconductor unit 40 and the photoconductor unit 40
Developing unit 50 swingably supported via shaft 5
And The photoconductor unit 40 is a photoconductor support unit.
41, and the photosensitive member supporting means 41 is
A pair of side wall members 411 (FIG.
2 shows only the rear side wall member) and the pair
Connecting members 412 connecting the lower portions of the side wall members 411
a, 412b. The connecting members 412a and 412a
12b, the inner surfaces facing each other are arranged in parallel,
Charging means mounting space 4 in which charging means to be described later is disposed between persons
12c is formed. In addition, the connecting members 412a and 41
2b, as shown in FIG. 5, the front end portion (in FIG. 5,
(Right side) does not reach the side wall member 411 on the near side.
The side end portion of the front side and the side wall member 411 on the front side are connected laterally.
They are connected by a member 412d. Attaching the charging means
The space 412c is located to face a charging area described later.
You. The photosensitive member supporting means 41 configured as described above is
It is integrally formed of resin. Photoconductor support means 41
Side of the pair of side wall members 411 constituting the developing unit 50
A support portion 413 having a mounting hole 414 is provided at the upper end of
Are provided. The mounting provided on the support portion 413
A developing housing (described later) of the developing unit 50 is inserted into the hole 414.
The support shaft 5 made of a metal bar disposed on the
As a result, the photoconductor unit 40 and the developing unit 50
It is supported so that it can swing mutually. The photoreceptor unit 40 has a photosensitive surface.
The photosensitive drum 42 on which a layer is formed is provided. Less than
Structure of photosensitive drum 42 and support of photosensitive drum 42
The holding structure will be described with reference to FIG. Photoconductor Dora
In the illustrated embodiment, the aluminum 42 is made of aluminum.
Drum body 420 having photosensitive layer mounted on the peripheral surface of cylinder
And a support shaft 4 for rotatably supporting the drum body 420
21. The drum body 420 includes the support shaft 42
It is rotatable in a state where the axial movement is restricted to the predetermined position of 1.
It is supported by. Drum constituting photoconductor drum 42
Driven at one end (right end in FIG. 5) of the main body 420
A gear 70 is mounted. The driven gear 70 is electrically conductive.
Mounting part 701 and helical teeth
It consists of a gear part 702 and a shaft insertion hole 703.
The part 701 is pressed into one end of the drum body 420.
You. The helical gear 702 has a thrust generated at the time of driving.
It is formed in an inclined direction that acts toward the other end.
You. Other than the drum main body 420 constituting the photosensitive drum 42
A flange 71 is attached to the end (the left end in FIG. 5).
Have been. The flange 71 is made of conductive synthetic resin.
The mounting portion 711, the locking claw portion 712, and the shaft insertion hole
713, and the mounting portion 711 is the drum body 4
20 is pressed into the other end. Configured like this
The photoconductive drum 42 has driven teeth mounted on both ends thereof.
Shaft insertion hole 703 provided in wheel 70 and flange 71
And 713, the support shaft 421 is inserted. This support shaft
An annular groove 422 is provided at a predetermined position of 421,
The locking claw portion 712 of the flange 71 is
Are engaged. Annular groove 422 and locking claw
The state of engagement with 712 is shown in an enlarged manner in FIG.
That is, the locking claw 712 has a triangular cross-section.
The inclined surfaces 712a and 712b form an annular groove 422.
Contact the upper edges of the side faces 422a and 422b,
The top part 712c of the locking claw part 712 formed in a square shape is
So as to contact the bottom surface 422c forming the annular groove 422
It is configured. Therefore, the photosensitive drum 42 is configured.
The drum body 420 is moved to the support shaft 421 at a predetermined position in the axial direction.
It is rotatably supported with its movement restricted. this
Shaft 421 supporting drum body 420 as described above
Are a pair of sides constituting the photosensitive member supporting means 41.
It is slidably supported by the wall member 411 in the axial direction. In addition,
Of the flange 71 attached to the other end of the drum body 420
A pad made of felt or the like is provided between the end face and the side wall member 411.
A hook 72 is provided. This packing 72
Contact the end surface of the flange 71 to rotate the photosensitive drum 42
It acts as a frictional resistance. Because of this, gear drive
Rotation fluctuation of the photosensitive drum 42 can be suppressed.
Wear. The driven gear 70 is a driving gear described later.
The direction indicated by the arrow in FIG.
2, electrostatic latent image forming area 423, developing area 424, and transfer area
425 are sequentially driven to rotate. The above-mentioned charging means mounted in the charging area 422 is mounted.
The lower peripheral surface of the photosensitive drum 42 is provided in the space 412c.
And charging means 43 disposed opposite to the charging means.
The charging unit 43 extends in the axial direction in parallel with the photosensitive drum 42.
Corona discharger 43 as a charger disposed
1 and a synthetic resin for mounting and holding the charging corona discharger
And a charger holding member 432.
The material 432 fits into the charging means mounting space 412c, and
It is positioned in a fixed position. The charging area 42
2 and the transfer area 425 on the peripheral surface of the photosensitive drum 42
The contacting foreign matter collecting brush 44 is in the axial direction of the photosensitive drum 42.
It is arranged along the direction. This paper dust collecting brush 44
The axis of the photosensitive drum 42 which is made of acrylic fiber or the like
Has the same length as the direction length, and
Formed in one piece with the material 432 and along the axial direction of the photosensitive drum 42.
Attached to the brush support member 440 disposed
You. The upper end of the charger holding member 432 is
Charging corona discharger 431 disposed in area 422 and foreign matter
The peripheral surface of the photosensitive drum 42 between the collecting brushes 44
Is formed so as to be close to
The prevention wall 47 is constituted. This toner intrusion prevention wall 47
Is attached to the peripheral surface of the photosensitive drum 42 and collects foreign matter.
The residue removed together with foreign matter such as paper dust by the brush 44
The foreign toner is not reliably captured by the foreign matter collecting brush 44 and drops.
When it is dropped, it invades above the corona discharger 431 for charging.
It has a function to prevent it from doing so. A pair of photosensitive member supporting means 41
The space between the side wall members 411 is supplied from diagonally upper left in FIG.
The transferred transfer paper is transferred onto the peripheral surface of the photoreceptor drum 42.
One of the pre-transfer guide plate pair 45 for guiding toward the shooting area 425
Is provided, and a lower guide plate 451 is provided.
The side guide plate 451 is formed integrally with the pair of side wall members 411.
ing. The upper surface of the lower guide plate 451 has a longitudinal direction
(In the direction perpendicular to the plane of FIG. 2)
The individual guide ribs 451a are integrally formed. Also below
The side guide plate 451 is also provided on the lower surface in the longitudinal direction (in FIG.
A plurality of reinforcing ribs 45 at intervals in a direction perpendicular to
1b is integrally formed, and the reinforcing rib 451b is
It is configured to contact the support shaft 5. Therefore,
The lower guide plate 451 is bent by a pressing force acting on the upper surface thereof.
Even if the reinforcing ribs 451b abut against the support shaft 5,
Occurrence can be prevented. Also, the lower guide plate 451
Is a pair of side wall members 41 constituting the photosensitive member support means 41.
Functions as a connecting member that connects the upper parts of the 1
In addition, the rigidity of the photosensitive member supporting means 41 can be improved.
it can. Furthermore, in the illustrated embodiment, the lower guide plate
451 is formed integrally with the pair of side wall members 411.
The photosensitive member rotatably supported by the pair of side wall members 411
Maintaining a high positional relationship with respect to the body drum 42
Can be. Note that the lower guide plate 4 in the illustrated embodiment is used.
Reference numeral 51 denotes a photosensitive drum when the process unit 4 is attached or detached.
It also functions as a contact preventing member for the photosensitive layer of the ram 42.
To the developing roller of the developing unit 50 which will be described later.
It also functions as a touch prevention member for
Transfer toner and transfer paper transport path
It also has a function to prevent it from adhering. A pair of the photosensitive member supporting means 41
Transfer is performed between the side wall members 411 in the transfer area 425.
Post-transfer guide that guides the transferred transfer paper to fixing means described later
A plate 46 is provided, and the guide plate 46 after the transfer is a pair.
Is integrally formed with the side wall member 411. Therefore, transcription
The rear guide plate 46 includes a pair of
Functions as a connecting member that connects the side wall members 411 to each other
In addition, the rigidity of the photosensitive member supporting means 41 can be improved.
it can. The post-transfer guide plate 4 in the illustrated embodiment.
Reference numeral 6 denotes a photosensitive drum when the process unit 4 is attached and detached.
Also functions as a contact preventing member for the photosensitive layer of the camera 42.
be able to. Next, the above-described development as an electrostatic latent image developing device
The unit 50 will be described. In the illustrated embodiment
Developing unit 50 includes a developer composed of a one-component toner.
A developing housing 51 is provided therein. This present
The image housing 51 includes a bottom wall 511 and a portion in front of the bottom wall 511.
From the rear end (the end in the direction perpendicular to the paper surface in FIG. 2)
Front wall 512a (see FIG. 3)
And a rear side wall 512b and a left side wall 513,
These are integrally formed by a synthetic resin, and the stirring chamber 514 is formed.
And the developing chamber 515. Developing housing 51
A stirring chamber 514 and a developing chamber 515 are provided on the bottom wall 511.
In the front-rear direction (the direction perpendicular to the paper surface in FIG. 2)
The provided partition wall 516 is integrally formed. this
Both left and right surfaces of the partition wall 516 are arc-shaped guide surfaces 516a.
And 516b. Development housing 51
Between the front and rear side walls 512 constituting the developing chamber 515 side
Is provided on the front and rear side walls 51.
2 are integrally formed. Note that the developing housing 51 is
A toner supply hole 518 is formed in the rear wall 512 that constitutes the above.
The toner supply hole 518 has a cap 51
9 are fitted. Developing housing constructed in this way
The front and rear side walls 512 are provided on the upper end of the developing chamber 515 on the side of the developing chamber 515.
The support shaft 5 is provided through the support shaft.
5 at both ends of the photosensitive member unit 40
41, the supporting portions 413 of the pair of side wall members 411.
By fitting the mounting hole 414 provided, the photosensitive member
The unit 40 and the developing unit 50 are supported so as to be swingable with each other.
Be held. The photosensitive member supporting means of the photosensitive member unit 40
41 and the lower end of the developing housing 51
Are coil springs 5 serving as spring means at the front end and the rear end.
2 are interposed, and the coil spring 52
The light body support means 41 and the developing housing 51 support the support shaft 5.
The points are biased toward each other. What
The developing housing 51 is located above and to the right, that is,
The photoconductor unit 40 side is open. The developing housing 51 contains a developing row.
Roller 53, supply roller 54, stirring means 55, and developing
The agent regulating means 56 is provided. The developing roller 53 is
The developing unit 51 is disposed in the developing chamber 515 of the developing
The front and rear side walls 512 forming the housing 51
The rotating shaft 531 mounted on the device and the outside of the rotating shaft 531
Including a solid synthetic rubber roller 532 fixed to the peripheral surface.
I have. The rotating shaft 531 is made of a suitable metal material such as stainless steel.
Can be formed from the ingredients. Solid synthetic rubber roller 53
2 is a relatively flexible and conductive material such as urethane
Composed of conductive solid synthetic rubber such as tan rubber
I have. In the illustrated embodiment, a solid synthetic rubber roller 5 is used.
32 surface roughness, ie specified in JISB 0601
10 point average roughness Rz is set to 5.0 to 12.0
Have been. In addition, the volume resistance of the solid synthetic rubber roller 532 is
Anti 10 ^Four -10 ⁹ It is set to about Ω · cm. Ma
The roller hardness of the solid synthetic rubber roller 532 is as shown in FIG.
In the embodiment, the Asker C hardness is set to 60 to 80.
Have been. The roller of the developing roller 53 thus configured
Roller 532 is formed on the right side of the developing housing 51.
The photosensitive drum 42 is exposed through the side opening.
Is positioned opposite to. Then, the developing roller 53
The peripheral surface of the constituting roller 532 is exposed to light in the developing area.
It is pressed against the peripheral surface of the body drum 42,
The peripheral surface of the roller 532 is slightly elastic at the nip
Is compressed. Rotating shaft 53 of developing roller 53
1 is a developing housing 51 as shown in FIG.
Is projected from the front wall 512a of the
A drive gear 501 is mounted, and the drive gear
Therefore, the direction indicated by the arrow in FIG.
In a developing area which is a contact portion between the photosensitive drum 42 and the photosensitive drum 42
To rotate from the lower side to the upper side. In addition,
The driven gear 501 is formed by a helical gear.
I have. A transmission spur tooth is provided inside the driven gear 501.
A car 502 is integrally formed. Above the rotating shaft 531
By the rotation, the roller 532 is also rotated in the direction indicated by the arrow.
The peripheral surface of the roller 532 is moved
3. The developer control area 534 and the development area 424 are sequentially shifted.
Be moved. In the illustrated embodiment, the current
A constant voltage of 300 V is imprinted on the rotating shaft 531 of the image roller 53.
Be added. The replenishing roller 54 is provided with the developing housing.
In the developing chamber 515 of the roller 51 in parallel with the developing roller 53.
It is arranged and forms the front of the developing housing 51.
A rotating shaft 541 rotatably mounted on the rear side wall 512;
A roller 542 fixed to the outer peripheral surface of the rotating shaft 541;
Contains. The rotating shaft 541 rotates the developing roller 53.
A suitable metal material such as stainless steel as in the case of the rotating shaft 531
Can be formed from Roller 542 is made of expanded silicone
Or foams such as urethane foam
You. The roller 542 is a nip portion with the developing roller 53
The roller 5 of the developing roller 53 in the developer holding area 533
32. Roller 54 of supply roller 54
The hardness of the foam that forms the developing roller 53 composes the developing roller 53.
Considerably smaller than the hardness of the roller 532 (for example,
Roller 542 is a developing roller
Nip by pressing against roller 532 of 53
Roller 542 is about 0.1 to 0.6 mm in the area
Desirably, it is sexually compressed. Roller 5
42 also has conductivity, and its volume resistance is 10 ^Two ~ 1
0 ⁶ It is set to about Ω · cm. Of the supply roller 54
The front end of the rotating shaft 541 has a developing housing as shown in FIG.
It is disposed so as to protrude from the front side wall 512a of the jing 51, and
The driven gear 503 is attached to the end of the
The driving gear 503 meshes with the transmission spur gear 502.
It is configured as follows. Therefore, the rotation axis of the supply roller 54
Reference numeral 541 denotes a direction indicated by an arrow in FIG.
2 and the photosensitive area of the photosensitive drum 42
And is driven to rotate upward from below. Illustrated
The direction indicated by the arrow, ie, the roller 5
Nip between the roller 42 and the roller 532 of the developing roller 53
From the upper side to the lower side in the developer holding area 533
It is driven to rotate. Due to the rotation of the rotation shaft 541,
Accordingly, the roller 542 is also driven to rotate in the direction indicated by the arrow.
In the illustrated embodiment, the rotation of the supply roller 54 is
The rotating shaft 541 has a voltage higher than the voltage applied to the developing roller 53.
A constant voltage of 450 V is applied. The peripheral speed V1 of the photosensitive drum 42 is
The peripheral speed V2 of the image roller 53 and the peripheral speed of the supply roller 54
V3 is set in a relationship of V1 <V2 <V3.
In the illustrated embodiment, the photosensitive drum 42
The relationship between the peripheral speed V1 and the peripheral speed V2 of the developing roller 53 is as follows.
1.2V1 ≦ V2 ≦ 2.5V1
The peripheral speed V2 of the roller 53 and the peripheral speed V3 of the supply roller 54
Is set to 1.0V2 ≦ V3 ≦ 2.0V2.
ing. The peripheral speed V2 of the developing roller 53 is 1.2 V1 or less.
, The supply of the developer to the photosensitive drum 42 becomes insufficient.
This causes a reduction in image density. Also, the developing roller
When the peripheral speed V2 of the 53 becomes 1.2V1 or less, after the transfer,
For the non-transferred developer adhered to the photosensitive drum 42
Since the scraping action of the developing roller 53 is reduced, non-transfer
Not generated because the developer cannot be removed from the photosensitive drum 42
This causes the so-called offset fog to occur. other
On the other hand, if the peripheral speed V2 of the developing roller 53 becomes 2.5 V1 or more,
Then, the driving torque of the developing roller 53 increases and
In addition, the developer may be scattered by the centrifugal force. Also replenish
When the peripheral speed V3 of the roller 54 becomes 1.0 V2 or less, the current
The supply of the developer to the image roller 53 becomes insufficient, and the image density decreases.
It may cause a decrease. Also, the peripheral speed V of the supply roller 54
3 is less than 1.0 V2, the current
Since the scraping action of the peripheral surface of the image roller 53 is weak,
The non-transferred developer adhered to the photosensitive drum 42 is developed
When the developer adheres to the roller 53, it is difficult to remove the developer.
This makes it difficult for the deposited developer to appear during the next development.
This can cause a blast phenomenon. On the other hand, the supply roller 54
When the peripheral speed V3 becomes 2.0 V2 or more, the supply roller 54
As the drive torque of the
Tendency to stay above the nip between the developing roller 54 and the developing roller 53
Causes a shortage of developer supply to the developing roller 53.
Become. In the stirring chamber 514 of the developing housing 51,
Is provided with a stirring means 55. The stirring means 55
Are arranged in parallel with the replenishing roller 54, and
The front and rear side walls 512 forming the housing 51
And the rotating shaft 551 attached to the
The fixed stirring member 552 and the stirrer 552
A stirring sheet member 553 having improved elasticity is included.
The stirring member 552 is formed of a synthetic resin,
In the longitudinal direction (the direction perpendicular to the plane of FIG. 2)
It has an opening. The stirring sheet member 553 is flexible and elastic.
For example, polyethylene terephthalate (PET)
P) It is formed of resin, and is
It is fixed to the edge by an adhesive or the like. in this way
The front end of the rotating shaft 551 of the constituted stirring means 55 is shown in FIG.
As shown in FIG.
The driven gear 504 is mounted at this end.
Is being worn. The driven gear 504 is connected to the supply row.
Driven spur gear 503 mounted on the rotating shaft 541 of the
And rotatably mounted on the front side wall 512a of the developing housing 51.
Via the mounted transmission gears 505, 506 and 507
Power transmission is connected. Therefore, the stirring means 55 is
In the direction indicated by the arrow.
You. The developer regulating means 56 is provided with
And presses against the peripheral surface of the roller 532 constituting the roller 32.
And a flexible elastic blade 561.
The blade 561 has a thickness of, for example, 0.1 to 0.2 mm.
Composed of stainless steel plate or spring steel plate of degree
And the length of the roller 532 constituting the developing roller 53
Has substantially the same longitudinal dimension. Blade 561
Is a bottom wall 5 whose base end constitutes the developing housing 51.
11 is provided at the open end of the photoconductor unit 40 side.
Attached to the door mounting portion 511a. That is, the blade 561
The base end of the blade mounting portion 511a and the holding plate 562
And is fixed by screws 563. Blur
The leading end of the node 561 is formed to be bent.
Constitute the developing roller 53 in the developer regulating region 534.
To be pressed against the peripheral surface of the roller 532
Have been. The developing housing 51 has an open state.
A lid 57 covering the upper part is mounted. The lid 57 is made of synthetic resin
And constitute the developing housing 51.
Front and rear side walls 512 and left side wall 513 and connection
It is fixed to the upper surface of the member 517 by an adhesive. This
The inner surface of the lid 57 is located at a position facing the supply roller 54.
Extends in the front-rear direction (the direction perpendicular to the paper in FIG. 2)
The regulating portion 571 projecting toward the developing chamber 515 is integrally formed.
Have been. Note that the lower end of the regulating portion 571 and the supply
Between the outer peripheral surface of the roller 542 constituting the roller 54
Are provided. In the illustrated embodiment, the development
The connecting member 517 constituting the housing 51 includes a seat.
A sealing member 58 is mounted. This sheet-like sheet
The member 58 is made of, for example, polyethylene terephthalate (P
ETP) Flexible sheet material such as resin
A roller constituting the developing roller 53
532 has substantially the same length as the axial length. Sheet
One end of the seal member 58 is connected to the connecting member 517.
Is fixed to the base by fixing means such as an adhesive.
Roller 53 whose end is curved to form developing roller 53
2 is elastically brought into contact with the peripheral surface. like this
The sheet-shaped sealing member 58 configured as described above is
The developing housing 5 together with the blade 561 of the control means 56
1 prevents the developer from being scattered from the opening on the photosensitive unit 40 side.
Stop. Process unit configured as described above
4 is attached to the housing body 21 of the body housing 20.
It is detachably attached to the machine frame 3 provided. Next
1, 4 and 5 for the body frame 3
It will be described with reference to FIG. The fuselage frame 3 is
At the position where the knit 4 is provided,
It is arranged on the housing body 21. Airframe 3
Is formed of a synthetic resin, and as shown in FIG.
It has a bottom wall 31, a near side wall 32 and a far side wall 33.
ing. The front side wall 32 of the body frame 3
One of the ends supporting the one end of the support shaft 421 of the body drum 42
A shaft support portion 34 is provided, and a support
The other shaft support 35 for supporting the other end of the shaft 421 is provided.
Have been. Provided on the front side wall 32 of the body frame 3
One of the shaft support portions 34 is formed so as to spread upward.
A guide groove 341 which is opened at the top and the guide groove 3
41 is formed by being connected to the lower end of
A fitting groove 342 having a corresponding width is provided. Above plan
The outer wall forming the inner groove 341 has an inward direction from the upper end.
A guide surface 341a is formed. Above fitting
The groove 342 is made of a spring steel plate or a stainless steel plate.
A pressing member 343 formed by bending a conductive plate material is provided.
I have. This pressing member 343 is an arm of the photosensitive drum 42.
And functions as a metal plate through the metal plate 344.
And is attached to the front side wall 32. In addition, metal
The plate 344 has a bottom wall whose lower end forms the body frame 3.
Frame base 345 made of a metal plate mounted on 31
And the photosensitive drum 42 is electrically conductive.
Gear 70 and flange 7 made of synthetic resin
1, a support shaft 421 made of a metal bar, a pressing member 343,
Body to the frame base 345 via the metal plate 344
Be used. Provided on the rear side wall 33 of the body frame 3
The other shaft support portion 35 is provided on the front side wall 32.
And is provided to face one of the shaft support portions 34
And extends upward like the shaft support 34.
A guide groove 351 formed and open at the top, and the guide groove
The diameter of the support shaft 421 formed to be connected to the lower end of
A fitting groove 352 having a corresponding width is provided. the above
The outer wall constituting the guide groove 351 is directed inward from the upper end.
Guide surface 351a is formed, and
The outer wall forming the fitting groove 352 is formed on the guide surface 35.
1a is formed continuously from the lower end of the shaft contact portion 352a.
Function. On the front side wall 32 of the body frame 3
Of the photosensitive drum 42 on the shaft support portions 34 and 35
One end of the photosensitive drum 42 when the support shaft 421 is mounted
Gear 3 meshingly engaged with driven gear 70 mounted on
6 are provided. Also, the front side of the body frame 3
The wall 32 is mounted on the rotating shaft 531 of the developing roller 53.
Drive gear 37 meshingly engaged with the driven gear 501
It is arranged. The drive gear 36 and the drive teeth
The wheel 37 is formed by a helical gear. In addition,
The drive gear 36 and the drive gear 37 are an electric motor (not shown).
Drive each through the appropriate gear transmission mechanism by the driving force of the motor.
It is configured to be moved. In the body frame 3 configured as described above,
The process unit 4 is mounted as follows. That is,
Cover 23 Constituting Body Housing 20 of Printer 2
Can be turned counterclockwise in FIG.
By this, a housing book constituting the body housing 20
The upper part of the body 21 is opened, and the body frame 3 is exposed.
You. Next, the process unit 4 is moved from above to the body frame
Attach to 3. At this time, the support shaft 4 of the photosensitive drum 42
21 are guide grooves 34 of shaft supports 34 and 35
1 and 351 guided by fitting grooves 342 and 35
2 and the support shaft 421 is directly supported by the body frame 3.
Is done. In this manner, the support shaft 421 is fitted with the fitting grooves 342 and 342.
And 352, constitute the photosensitive drum 42
The driven gear 70 attached to one end of the drum body 420
The developing roller 53 is engaged with the driving gear 36.
The driven gear 501 mounted on the rotary shaft 531
It engages with the wheel 37. The support of the photosensitive drum 42
As shown in FIG. 5, one end of the holding shaft 421 has one end of the pressing member 3.
43 and is pressed leftward, and the other end is
It is maintained in a state of being abutted against 52a. Therefore,
State in which axial movement is restricted at a predetermined position by the support shaft 421
The drum body 420 rotatably supported by the
It is reliably positioned at a predetermined position of the beam 3. like this
Next, the process unit 4 is mounted on the body frame 3 from above.
Then, the support shaft 421 of the photosensitive drum 42
The photoconductor unit 40 is directly supported by the
It is necessary to have the vertical accuracy and the assembly accuracy with the machine frame 3.
Move the photosensitive drum 42 to a predetermined position without
Can be reliably positioned. The aircraft frame
3, the photosensitive drum 42 is positioned at a predetermined position.
Positioning the process unit 4 in a predetermined position
Positioning means (not shown) is provided.
As a result, the process unit 4 is positioned at a predetermined position on the body frame 3.
Attached to the device. As described above, the process unit
4 is mounted on the body frame 3, and the cover 23 is
By turning clockwise in FIG. 1 around
The upper part is closed. As shown in FIG.
Disposed on a housing body 21 constituting the jing 20.
On the bottom wall 31 of the body frame 3, an optical system unit is provided.
All the laser units 60 are provided. This laser
The unit 60 includes, for example, a word connected to the printer 2.
Laser light corresponding to the print data from the processor
In the electrostatic latent image forming area 423 of the
Irradiates the photosensitive layer of the optical drum 42 to form an electrostatic latent image.
You. Note that an electrostatic latent image is formed by the laser unit 60.
The photosensitive drum 42 is supported by its support shaft 4 as described above.
21 is directly supported at a predetermined position of the body frame 3
The laser unit disposed at a predetermined position on the body frame 3.
Since the positional relationship with the
An electrostatic latent image is reliably formed at a predetermined position on the photosensitive drum 42
be able to. Also, the body housing 20 of the printer 2
The post-transfer guide plate is provided
A fixing roller pair 61 is disposed downstream of the fixing roller 46.
A discharge roller pair 62 is disposed downstream of the roller pair 61.
I have. Further, a discharge tray is provided downstream of the discharge roller pair 62.
63 are provided. The body housing 20 of the printer 2 is constructed.
The transfer paper is placed on the upper left of FIG.
A paper feed tray 64 to be placed is provided. This paper feed
A paper feed roller 65 is disposed downstream of the ray 64,
The feed roller 65 is driven by a driving unit (not shown) as shown in FIG.
In the direction indicated by the arrow. This pay
A friction pad 66 for separating paper is opposed to the paper roller 65.
It is arranged. In the transfer area 422,
A non-contact type transfer roller 67 is disposed to face the body drum 42.
Is established. This transfer roller 67 is used in the illustrated embodiment.
Is made of conductive urethane foam
And is rotatably supported by the cover 23. Transcription low
The outer diameter of the roller 67 is larger than the transfer roller 67 at both ends.
(Not shown) made of insulating material such as synthetic resin having
Are mounted, and the color is the peripheral surface of the photosensitive drum 42.
, So that the transfer roller 67 is
Sliding following the rotation of the photosensitive drum 42
You. The peripheral surface of the transfer roller 67 and the photosensitive drum 42
Is set to about 0.5 mm.
The transfer roller 67 configured as described above has, for example, 10
A constant current of μA is applied. Also, the cover 23
Upper guide plate 45 constituting the other of the pre-transfer guide plate pair 45
2 are provided. The printer 2 in the illustrated embodiment has been described above.
The operation will be described below.
You. Based on a print command from a word processor (not shown), etc.
Then, the above members start to operate, and the charging corona discharger 4
3 makes the surface photosensitive layer of the photosensitive drum 42 a specific polarity.
It is charged substantially uniformly. Next charged photoconductor drum
42 from the laser unit 24 on the surface of the photosensitive layer 42.
Laser light corresponding to the print data from the processor
And an electrostatic latent image is formed. In this way, the photoconductor
The electrostatic latent image formed on the photosensitive layer of the drum 42 is
The toner image is developed by the developing action of the unit 50.
It is. The developing operation of the developing unit 50 is described below.
Details will be described later. On the other hand, the
The transfer paper is subjected to the action of the paper feed roller 29 and the friction pad 30.
Are fed one by one. And the transfer paper is a pre-transfer plan
The photosensitive drum 42 and the transfer roller 3 are guided by the inner plate pair 45.
1 and is formed on the photosensitive drum 42 on the surface thereof.
The formed toner image is transferred. The toner image has been transferred
The transfer paper is guided by a guide plate 46 after the transfer, and
25. The toner image is formed by the fixing roller pair 25.
The heat-fixed transfer paper is discharged by a discharge roller pair 26.
The paper is discharged onto the paper tray 27. On the other hand, through the transfer area 425
The outer peripheral surface of the photosensitive drum 42
Paper dust adhering to its peripheral surface when passing through
Foreign matter such as is removed by the foreign matter collecting brush 44. This
In this case, the peripheral surface of the photosensitive drum 42 together with foreign matter such as paper dust
The residual toner adhering to the surface is also removed. This removed
Remaining toner is not reliably captured by the foreign matter collecting brush 44
May fall on The dropped toner is charged
Causes Charging Unevenness When Accumulated on Corona Discharger 431
However, in the illustrated embodiment, the toner
The stop wall 47 (470) allows the toner
Intrusion into the Rona discharger 431 is prevented. Next, the developing operation of the developing unit 50 will be described.
explain about. By starting the operation of the developing unit 50,
The developing roller 53, the supply roller 54, and the stirring means 5
5 are driven by driving means (not shown) in directions indicated by arrows.
It is driven to rotate. Stirring member 55 constituting stirring means 55
2 and the stirring sheet member 553 rotate in the direction indicated by the arrow.
As a result, the developer accommodated in the stirring chamber 514 is stirred.
The replenishing roller 54 passes over the partition wall 516 while being stirred.
Is supplied into the developing chamber 514 from above. In addition,
And the regulating portion 571 formed on the inner surface of the lid 57,
If the amount of the developer supplied into the developing chamber 514 becomes excessive,
To be restricted. Thus, by the stirring means 55
The supplied developer is supplied onto the roller 542 of the supply roller 54.
And the developer is held with the roller 532 of the developing roller 53
It is transported to the nip area 533. In addition, supply low
Roller 54 and developing roller 53 are in the nip portion as described above.
In the developer holding area 533 from the upper side to the lower side
The supply roller 54 to the developing roller 53
Supply of developer to the
Can be Further, the supply roller 54 and the developing roller 5
3 is a developer holding area 533 which is a nip portion as described above.
Requires large driving force to rotate in the same direction at
It can be driven reliably without the need. As described above, the supply roller 54 and the developing
Conveyed to the developer holding area 533 which is the nip portion of the roller 53
The developed developer is supplied to a roller 53 constituting the developing roller 53.
2 and carried toward the developer regulating area 534.
Sent. At this time, the supply roller 54 and the developing roller 53
Are in the developer holding area 533 which is the nip as described above.
In the same direction from top to bottom
The developer is held by the developing roller 53 through the nip portion between the two.
To the developer regulating area 534 and the developing area 535
So they rub against each other when passing through the nip
It is charged, and so-called fogging is prevented. In the developer regulation area 534, the developer regulation
The blade 561 of the control means 56 is a roller of the developing roller 53
532 acts on the developer held on the peripheral surface,
The amount of developer held on the peripheral surface of the roller 532 is regulated to a required amount.
To form a thin layer. In addition, in the developer regulation area 534
Is regulated by the blade 561 of the developer regulating means 56
And is scraped off on the bottom wall 511 of the developing housing 51.
The supplied developer rotates the supply roller 54 in the direction indicated by the arrow.
The partition wall 516 is not stopped because it is hampered.
Along the guide surface 516b. As described above, the developer holding area 533
On the peripheral surface of the roller 532 constituting the developing roller 53
Held in the developer regulating area 534
Formed into a thin layer by the action of 56 blades 561
The supplied developer is rotated in a direction indicated by an arrow to develop area 424.
Transported to In the developing area 424, the photosensitive drum
Electrostatic latent image on the electrostatic photoreceptor disposed on the peripheral surface of 42
Is applied with a developer, and the electrostatic latent image is developed into a toner image.
You. For example, an electrostatic latent image is charged to about + 600V.
Non-image area and an image charged to about + 120V
An image area, and a toner as a developer is attached to the image area.
It is dressed (so-called reversal development). With the photosensitive drum 42
The developing roller 53 rotates in the direction indicated by the arrow in FIG.
In the development area 535,
Roller 5 constituting peripheral surface of ram 42 and developing roller 53
32 and move it from the bottom to the top in the same direction.
Can be The peripheral speed V2 of the roller 532 and the photosensitive drum 4
2 is set to 1.2V1 ≦ V2 ≦ 2.5V1.
Is fixed, the roller 532 of the developing roller 53
When sufficient developer is conveyed to the development area 535,
Of the roller 532 with respect to the peripheral surface of the photosensitive drum 42
Due to the rubbing action of the peripheral surface, it is temporarily attached to the non-image part of the electrostatic latent image.
The applied developer is peeled off properly, so that the
It is possible to obtain a good toner image with a degree
it can. On the other hand, a roller 532 constituting the developing roller 53
Used after passing through the developing area 424 while being held on the peripheral surface of the
The remaining developer may cause the developing roller 53 and the supply roller 54
It is transferred to the surface of the replenishing roller 54 at the stop. Replenishment
The peripheral speed of the roller 54 is larger than the peripheral speed of the developing roller 53
Move the developer at the nip
Therefore, when passing through the developing area 535,
Reduce the adhesive force of the non-transferred developer that is being worn and collect it
And therefore adheres to the developing roller 53.
Prevents so-called ghosting caused by non-transferred developer
can do. Note that, as in the illustrated embodiment,
Operation is performed with the optical drum 42 and the developing roller 53 pressed against each other.
The peripheral speed V1 of the photosensitive drum 42 is
If the peripheral speed V2 of the roller 53 is smaller than
In driving the drum 42 and the developing roller 53, the photosensitive drum
The arm 42 performs a braking action. Therefore, photosensitive
Driven gear 70 mounted on body drum 42 and developing roller
C of the driven gear 501 mounted on the rotation shaft 531
The direction of the teeth is such that the thrust generated during driving is
Are formed in opposite directions with respect to each other
I have. As described above, an embodiment in which the present invention is applied to a printer
However, the present invention is limited to the illustrated embodiment.
It is not specified.
Without departing from the scope of the technical idea of the present invention.
Various variations or modifications are possible. The image forming apparatus according to the present invention has the following features.
The configuration has the following functions and effects. That is, according to the present invention, the photosensitive drum and the photosensitive drum
A photosensitive body comprising a photosensitive body supporting means equipped with a photosensitive drum
By attaching the body unit to the body frame,
Since the body drum is supported directly on the fuselage frame, the photoconductor
Unit assembly accuracy and assembly with the body frame
The photosensitive drum without increasing the accuracy
It can be reliably positioned at a fixed position. Therefore, the fuselage
Position with the optical system unit arranged at a predetermined position on the frame
The electrostatic latent image on the photoreceptor
It can be reliably formed at a predetermined position on the drum. Ma
According to the present invention, the shaft support portions of the body frame are
Guide groove that is formed so as to expand toward
And formed directly at the lower end of the guide groove,
A fitting groove having a width corresponding to the diameter is provided.
Guide that slopes inward from the upper end on the outer wall that constitutes
Surface, the photoreceptor unit is
When mounted on the system, both ends of the support shaft constitute a pair of shaft support parts
Is guided by the guide surface of the guide groove
Wearing becomes easy. ## EQU1 ##

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view schematically showing an embodiment of an image forming apparatus configured according to the present invention. FIG. 2 is a sectional view of a process unit provided in the image forming apparatus shown in FIG. FIG. 3 is a perspective view of a main part of a process unit provided in the image forming apparatus shown in FIG. 2; 4 is a perspective view of a main part of a body frame of the image forming machine shown in FIG. FIG. 5 is a sectional view taken along line AA in FIG. 1; 6 is an enlarged sectional view of a main part showing an engagement state between an annular groove formed on a support shaft of the photosensitive drum in FIG. 5 and a locking claw portion of a flange mounted on the drum main body. [Description of Signs] 2: Printer 3: Body frame 4: Process unit 5: Support shaft 20: Body housing 21: Housing body 23: Cover 31: Bottom wall 32 of body frame: Front side wall 31 of body frame: Body frame Side wall 34: shaft support 35: shaft support 36: drive gear 37 of the photoconductor drum: drive gear 40 of the developing roller: photoconductor unit 41: photoconductor support means 42: photoconductor drum 43: charging means 44 : Foreign matter collecting brush 45: Guide plate before transfer 46: Guide plate after transfer 47: Toner intrusion prevention wall 50: Developing unit 51: Developing housing 52: Coil spring 53: Developing roller 54: Supply roller 55: Stirrer 56: Developing Agent regulating means 57: lid 58: sheet-shaped seal member 60: laser unit 61: fixing roller pair 62: discharge roller pair 63: discharge tray 6 4: paper feed tray 65: paper feed roller 66: friction pad 67: transfer roller 70: driven gear 72 of the photosensitive drum: packing 71: flange 341: guide groove 342: fitting groove 343: pressing member 344: metal plate 345: Frame base 351: Guide groove 352: Fitting groove 352a: Shaft contact portion 411: Side wall member 412a of photoconductor support means: Connection member 412b of photoconductor support means: Connection member 431 of photoconductor support means: Charging corona Discharger 420: drum body 421 of photosensitive drum: support shaft 422 of photosensitive drum: charging area 423: electrostatic latent image forming area 424: developing area 425: transfer area 470: toner intrusion prevention wall 501: cover of developing roller Driving gear 503: Driven gear 504 of the supply roller: Driven gear 514 of each group means: Stirring chamber 515: Developing chamber 517: Developing housing Of the connecting member 533: the developer holding zone 534: the developer regulating zone 561: Blade

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroyuki Hamakawa 1-2-28 Tamazo, Chuo-ku, Osaka-shi Mita Kogyo Co., Ltd. (72) Inventor Yu Watanabe 1-2-28 Tamazozo, Chuo-ku, Osaka-shi Mita Kogyo (56) References JP-A-5-297649 (JP, A) JP-A-1-242812 (JP, A) JP-A-56-1222047 (JP, A) JP-A-6-130746 (JP, A) A) JP-A-7-160145 (JP, A) JP-A-8-30058 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 21/16 G03G 15/00 550 G03G 21/00 350

Claims (1)

(57) [Claims] 1. A photoconductor drum, and the photoconductor drum is mounted on the photoconductor drum.
The photoconductor unit comprising the photoconductor support means
Removably attach to the unit frame where the unit is installed
In an image forming machine,The photosensitive drum includes a drum main body and the drum main body at a predetermined position.
It is supported rotatably in a state where the axial movement is
And a support shaft mounted on the photoconductor support means, The body frame supports one end of each of the support shafts.
With a pair of shaft supports, The pair of shaft supports are formed so as to extend upward.
Contacting the lower end of the guide groove,
A fit formed subsequently and having a width corresponding to the diameter of the support shaft
A mating groove is provided, and the outer wall forming the guide groove has an upper end
A guide surface that is inclined inward is formed. An image forming machine comprising: