JPH06258983A - Image forming device - Google Patents

Abstract

PURPOSE:To stabilize the abutting state of a cleaning means on an image carrier and to prevent a failure in cleaning by setting the direction of the resultant force of the pressurizing force of a developing means and that of a transfer means, with respect to the image carrier, toward the abutting position of the cleaning means on the image carrier. CONSTITUTION:The pressurizing force from a transfer drum 4 shown by the arrow Ftr and that from a developing sleeve 7f shown by the arrow Fdev act out the image carrier 6a and the resultant force is shown by the arrow F. The resultant force of force from a cleaning blade 6cl and the resultant force F is the force actually working on the image carrier 6a. Therefore, the direction of the resultant force F of the pressurizing force of the developing sleeve 7f and the transfer drum 4 against the image carrier 6a is set in the range of + or -15 deg. with respect to the abutting position of the cleaning blade 6cl on the image carrier, a stable cleaning ability can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine or a printer, and more particularly to a color image forming apparatus capable of forming a color image using a plurality of developing means.

[0002]

2. Description of the Related Art A color image forming apparatus using an electrophotographic system today is constructed as shown in FIG. That is, the image bearing member 51 is irradiated with light from the optical unit 50 to form a latent image corresponding to each color component. At the same time, the recording medium 53 housed in the cassette 52 is fed by the feeding means 54 and wound around the transfer drum 55, the transfer drum 55 is rotated, and the latent image on the image carrier 51 is developed by the developing means 56. Development is performed with a developer corresponding to each color component, and the developed image is transferred to the recording medium 53 on the transfer drum 55. This transfer process is repeated for each color to obtain a multicolor image, and the transferred image is fixed by the fixing means 57. The developer remaining on the image carrier 51 after the transfer is scraped off by the cleaning blade 58a of the cleaning device 58.

[0003]

However, in the above-mentioned conventional example, the gap holding member (not shown) provided on the developer carrying member 56a for each color of the developing means 56 is brought into contact with the image carrying member 51, and Since the space between both members is maintained, the position of the image carrier 51 becomes unstable when the developing means 56 is switched when developing with a developing device corresponding to each color component, and the cleaning device There has been a problem that the contact state of 58 with the cleaning blade 58a changes, resulting in defective cleaning.

Therefore, an object of the present invention is to solve the above-mentioned problems, and to prevent the cleaning failure by stabilizing the contact state of the cleaning means with the image carrier.

[0005]

A typical image forming apparatus according to the present invention for achieving the above object has a latent image formed on the image carrier by charging the image carrier by a charging means. Is an image forming apparatus for developing the image on the image carrier by a developing means, transferring the developed image to a recording medium by the transfer means, and removing the developer remaining on the image carrier by the cleaning means. The pressing force of the means,
It is characterized in that the direction of the resultant force of the pressing force of the transfer means with respect to the image carrier is set within a range of ± 15 degrees with respect to the contact portion of the cleaning means with respect to the image carrier.

[0006]

In the image forming apparatus having the above structure, the direction of the resultant force of the pressing force of the developing unit against the image carrier and the pressing force of the transfer unit against the image carrier is approximately the image carrier of the cleaning unit. Since the setting is made toward the body contact position, even when the developing unit switches the developing unit for developing corresponding to each color component, the contact state of the cleaning unit with respect to the image carrier is stable, Cleaning failure can be prevented.

[0007]

【Example】

First Embodiment Next, a first embodiment according to the present invention will be specifically described with reference to the drawings. 1 is an explanatory view of the overall configuration of a laser beam printer which is one mode of the image forming apparatus, FIG. 2 is an explanatory view showing the contact state of the developer carrying member and the transfer means with respect to the image carrying member, and FIG. 3 is FIG. 4 is an enlarged schematic view of the developing means, and FIG. 4 is an explanatory view of the arrangement of the process means acting on the image carrier.

[Overall Structure] First, the overall structure of the image forming apparatus will be briefly described. In this apparatus, as shown in FIG. 1, a recording medium 2 contained in a cassette 1 constituting a stacking means is fed by a feeding means 3. It is fed and wound around the peripheral surface of the transfer drum 4 which constitutes the transfer means. On the other hand, light is emitted from the optical unit 5 to the image carrier unit 6 according to a color image,
A latent image is formed on the image carrier, and this latent image can be rotated and moved.
The image is developed by the developing means 7 which is equipped with one developing device, and is multi-transferred onto the recording medium 2 on the transfer drum 4 to form a color image. Then, the recording medium 2 is conveyed to the fixing means 8 to fix the transferred image on the recording medium 2, and is ejected to the ejection portion 10 at the upper part of the apparatus by the ejection roller pair 9.

The image carrier unit 6 and the developing device in the developing means 7 are detachable from the apparatus main body 11.

Next, the structure of each part of the image forming apparatus will be sequentially described in detail.

{Loading Means} The loading means is for loading the recording media 2 and setting it on the apparatus main body 11. In this embodiment, a loading means for loading the cassette 1 on the inner bottom of the apparatus is provided. There is. That is, as shown in FIG.
A mounting recess of the cassette 1 is provided on the inner bottom portion of the disk, and a guide rail 11a is provided on the surface facing the recess in the front and back directions of FIG. On the other hand, on both sides of the cassette 1, there are provided locking projections 1a which are locked to the guide rails 11a and are slidable.

Thus, the cassette 1 is provided with a handle recess (not shown), and the cassette 1 can be inserted or removed along the guide rail 11 from the front side to the rear side of the apparatus body. By setting the cassette 1, the recording medium 2 is set in the apparatus main body 11.

The means for stacking the recording medium 2 may be the one in which the cassette 1 can be attached to and detached from the mounting portion as described above, or the apparatus main body 11 without being removed.
It is also possible to provide a recording medium stacking base that is slidable with respect to 11 and set the recording medium 2 on this stacking base.

[Feeding means] The feeding means 3 feeds the recording medium 2 in the cassette 1 to the image forming section, and the cassette containing a plurality of recording media 2 in the inner bottom of the apparatus main body 11. 1 is loaded, the feeding rollers 3a and 3b are driven and rotated according to the image forming operation at the time of image formation, the recording medium 2 in the cassette 1 is separated and fed one by one from the uppermost portion, and guided by the guide plate 3c. Then, the sheet is fed so as to abut against the registration roller pair 3d. And the registration roller pair 3
The recording medium 2 is driven so that d is synchronized with the image forming operation.
To the transfer drum 4.

[Transfer Means] The transfer means is for transferring the developed image developed by the developing means 7 onto the recording medium 2. In this embodiment, the recording medium 2 is wound around the transfer drum 4 and the developer of each color is developed. The (toner) is transferred onto the recording medium 2.

The transfer drum 4 according to this embodiment is formed by stretching a dielectric sheet 4b on a hollow support 4a. The transfer drum 4 is rotatably supported by a shaft 4c,
By transmitting the driving force of the drive motor to a gear (not shown) fixed to the transfer drum 4, the gear is configured to rotate in the arrow direction in FIG. 1 at substantially the same speed as the image carrier according to the image forming operation. .

A gripper 4d is provided at a predetermined position on the outer circumference of the transfer drum 4, and holds the leading end of the fed recording medium 2. Further, the electrostatic attraction roller 4e is the transfer drum 4
The recording medium 2 is press-contacted to the outer periphery of the transfer drum 4 such that the recording medium 2 is sandwiched between the electrostatic adsorption roller 4e and the transfer drum 4, and the electrostatic adsorption roller 4e and the transfer drum 4 are attached. A voltage is applied between the recording medium 2 and the dielectric sheet 4b of the transfer drum 4 to induce an electric charge, and the recording medium 2 is electrostatically attracted to the outer periphery of the transfer drum 4. is doing.

The method of attracting the recording medium 2 to the transfer drum 4 is not limited to the electrostatic attraction, but may be a suction method using air or the like.

Further, since the transfer drum 4 needs to be maintained at a constant gap or pressure with respect to the image carrier 6a, an abutting member 4f is provided at an end portion on the support 4a, and this contact member 4f is provided. The eccentric cam 4g, which rotates in the direction of the arrow in FIG. 1, is pressed against the center of the image carrier 6a with a force of 1 kg.

In FIG. 1, reference numeral 12 is a separation claw for separating the recording medium 2 from the transfer drum 4 after gripping by the gripper 4d, and 13 is for contacting the surface of the transfer drum 4 to clean the surface. Cleaning device. The separating claw 12 and the cleaning device 13 are each configured to be swingable in the direction of the arrow in FIG.

{Optical Unit} The optical unit 5 irradiates light to form an electrostatic latent image on the image carrier. As shown in FIG. 1, when the image signal is applied to the laser diode 5a, the laser diode 5a outputs the image light corresponding to the image core to the polygon mirror 5 as shown in FIG.
Irradiate b. The polygon mirror 5b is rotated at high speed by the scanner motor 5c, and the image light reflected by the polygon mirror 5b is irradiated from the exposure section of the image carrier unit 6 through the image forming lens 5d and the reflecting mirror 5e to expose the image carrier. Selectively expose.

{Image bearing unit} Image bearing unit 6
Is an image carrier 6a, which is a photoconductor drum, and the image carrier 6a.
It has a charging means 6b and a cleaning means 6c as process means acting on a.

(Image bearing member) Image bearing member 6a according to the present embodiment.
Is OPC, AS on the outer peripheral surface of the aluminum cylinder.
A photoconductive material such as i, CdS, or Se is applied to form a photoconductive layer, and the rotating shaft 6a1 is rotatably supported on the frame of the image carrier unit. By transmitting the driving force of a drive motor (not shown) to the rotary shaft 6a1, the image carrier 6a is rotated in the arrow direction of FIG. 1 in accordance with the image forming operation. A charging means 6b is provided on the periphery of the image carrier 6a.
Also, the cleaning means 6c is arranged, and the image carrier unit 6 is attachable to and detachable from the apparatus main body 11. That is, it can be replaced according to the life of the image carrier 6a.

(Charging Means) The charging means 6b according to this embodiment.
Is provided with a metal shield such as aluminum around three sides of the tungsten wire, and positive or negative ions generated by applying a high voltage to the tungsten wire are moved to the surface of the image carrier 6a, and the image carrier 6a is The surface of is uniformly charged.

(Cleaning Means) Cleaning Means 6
Reference numeral c is for cleaning the toner remaining on the image carrier 6a after the toner visualized on the image carrier 6a by the developing means 7 is transferred to the recording medium 2. The cleaning means 6c according to this embodiment scrapes off the toner on the image carrier 6a by the cleaning blade 6c1 and sends it to the waste toner container attached to the side surface of the main body by the waste toner carrying screw 6c2. When the toner in the waste toner container is full, it is removed and replaced. In this embodiment, the cleaning blade 6c1 is attached to the image carrier 6a.
00 ~ 800g It is pressurized with heavy force.

{Developing means} In recent years, a one-component developing system using only a non-magnetic toner has been proposed instead of the two-component developing system using a mixture of a non-magnetic toner and a magnetic carrier as a developer. Compared to the two-component development method, this method does not require a developer mixing means, a means for maintaining a constant mixing ratio, a magnet for carrying and carrying the developer, and the like, and it is possible to provide a smaller and lower cost device. Is. In this embodiment, a one-component developing method using only non-magnetic toner is adopted.

The developing means 7 is for visualizing the latent image formed on the image carrier 6a, and in the present embodiment, it is possible to develop each color of yellow, magenta, cyan and black. It has four developing devices 7a, 7b, 7c, 7d.

As shown in FIG. 3, each of the developing devices 7a to 7a
d is swingably attached to the developing unit 7e around the shafts 7a1 to 7d1, and the developing unit 7e is pivotally attached to the apparatus main body 11 around the shaft 7e1. Further, the developing unit 7e is provided with an eccentric cam 7g for pressing a predetermined developing device against the image carrier 6a. Therefore, each of the developing devices 7a ...
Even if the developing unit 7e rotates due to its own weight, the posture of 7d is always kept constant. At the developing position, a predetermined developing unit is pressed against the image carrier 6a by the eccentric cam 7g with a force of 1 kg. It has become so. At this time, the abutting member 7 is attached to the end of the developing sleeve 7f so that the developing sleeve 7f of the developing device faces the image carrier 6a with a minute gap (about 150 to 450 μm).
h is provided (see FIG. 2).

At the time of image formation, a developing device 7a corresponding to each color development of yellow, magenta, cyan and black.
~ 7d is rotated around the shaft 7e1, the eccentric cam 7g
The developing sleeve 7f of the predetermined developing device causes the image carrier 6
After being pressed against a and the developer bearing member is positioned so as to face the image bearing member 6a with a minute gap (about 150 to 450 μm), the developed image with the toner of each color is placed on the image bearing member 6a. Form sequentially.

That is, the developing device containing the toner corresponding to the color to be developed sends the toner to the applying roller 7j by the toner feeding mechanism 7i, and the toner is applied to the outer circumference of the developing sleeve 7f rotated by the rotating applying roller 7j and the developing blade 7k. A layer is formed and a charge is imparted to the toner by triboelectric charging. By applying a developing bias between the developing sleeve 7f and the image carrier 6a on which the latent image is formed, toner development is performed on the image carrier 6a according to the latent image.

Further, the developing sleeves 7f of the developing devices 7a to 7d are connected to high-voltage power sources for color developing provided in the apparatus main body 11 when the developing devices are rotationally moved to the developing position.
A selective voltage is applied for each development of each color.

The material of the developing blade 7k is preferably nylon or the like for imparting a negative charge to the toner, silicon rubber or the like for imparting a positive charge, and is a material that is charged opposite to the polarity of the toner. Is preferred. Further, the peripheral speed of each developing sleeve 7f is 1.0 to the peripheral speed of the image carrier 6a.
It is preferable to set it in the range of 2.0.

[Fixing Means] The fixing means 8 is for fixing the transfer image formed on the recording medium 2 wound around the transfer drum 4 by the developing means 7, and as shown in FIG. The fixing roller 8b is in pressure contact with the recording medium 2 and applies heat and pressure to the recording medium 2.

When the recording medium 2 separated from the transfer drum 4 passes through the fixing section 8, it is conveyed by the driving roller 8a and heat and pressure are applied by the fixing roller 8b.
As a result, the image forming toner is fixed on the recording medium 2.

A cleaning member 8c is in contact with the fixing roller 8b, and the toner adhering to the roller 8b is removed by the cleaning member 8c.

[Image Forming Operation] Here, the operation of forming an image by the above apparatus will be described. The feeding rollers 3a and 3b shown in FIG. 1 are rotated to separate one recording medium 2 in the cassette 1. , And feed it to the transfer drum 4. The transfer drum 4 rotates in the direction of the arrow in FIG. 1 to grip the front end of the fed recording medium 2 with a gripper 4d, and electrostatically adsorbs the peripheral surface thereof.

The image carrier 6a is rotated in the direction of the arrow in FIG. 1 in synchronization with the rotation of the transfer drum 4, the surface of the image carrier 6a is uniformly charged by the charging means 6b, and the optical unit 5 is used. The yellow image is irradiated with light to form a yellow latent image on the image carrier 6a. At the same time when the latent image is formed, the developing device containing the yellow toner is attached to the image carrier 6a.
By driving so that the yellow toner adheres to the latent image on the image carrier 6a, a voltage of substantially the same potential as the charging polarity of the image carrier 6a is applied to perform yellow development so that the yellow toner adheres to the latent image on the image carrier 6a. .

Further, a voltage having a polarity opposite to that of the toner is applied to the transfer drum 4 so that the toner on the image carrier 6a is transferred.
Transfer to the upper recording medium 2.

After the transfer, the toner remaining on the image carrier 6a is scraped off by the cleaning blade 6c1 and sent to the waste toner container by the waste toner carrying screw 6c2.

When the transfer of the yellow toner is completed as described above, the developing device accommodating the toner of the next color is rotationally moved and positioned at a position facing the image carrier 6a. Then, latent images for magenta, cyan, and black are formed and toners are sequentially transferred to form a color image on the recording medium 2.

After the image formation, the recording medium 2 is separated by the separating claw 12.
Then, the toner is separated from the transfer drum 4 and conveyed to the fixing means 8. After the toner is fixed by the fixing means 8, the toner is discharged to the discharging portion 10 by the discharging roller pair 9 and the image formation is completed.

{Position of cleaning blade contacting image carrier} Next, the position of the cleaning blade 6c1 contacting the image carrier will be described with reference to the drawings. As shown in FIG. 4, the image carrier 6a is acted upon by the pressing force from the transfer drum 4 indicated by the arrow Ftr in the figure and the pressing force from the developing sleeve 7f indicated by the arrow Fdev in FIG. The resultant force is represented by arrow F in the figure. Therefore, the resultant force of the cleaning blade 6c1 and the above-mentioned resultant force F becomes the actual force acting on the image carrier 6a.

However, since the developing means 7 switches the developing devices 7a to 7d corresponding to each color component, the pressing force Fdev of the developing sleeve 7f against the image carrier 6a fluctuates.

On the other hand, since the image carrier 6a is a replacement part (consumable item), it is difficult to firmly fix the image carrier 6a to the apparatus main body 11. In order to secure this mounting strength, the cost and size of the apparatus are large. And the ease of replacement is impaired. Therefore, in reality, the image carrier 6a causes a backlash of about 50 to 200 μm, the position of the image carrier 6a changes due to the fluctuation of the pressing force Fdev, and the cleaning blade 6c1 is in contact with the image carrier 6a. Fluctuates, and as a result, defective cleaning occurs.
Particularly, in the case of the image carrier unit 6 in which the charging unit 6b, the cleaning unit 6c and the like are integrally formed around the image carrier 6a,
The above-mentioned problems are remarkable in terms of ease of replacement and cost.

Table 1 below shows the results of observing the occurrence of defective cleaning when the angle of the cleaning blade 6c1 at the position where the cleaning blade 6c1 abuts the image carrier is changed. By changing the angle θ (the counterclockwise direction is positive from the cleaning blade 6c1) formed by the resultant force F and the contact position of the cleaning blade 6c1 with respect to the image carrier 6a, the cleaning failure occurs at 5000 sheets and 10000 sheets. It was examined whether or not it occurred (◯ means good, x means poor cleaning).

[0046]

[Table 1]

As can be seen from Table 1, in the case where the angle θ is in the range of 0 ° to ± 15 °, no cleaning failure occurs at 5000 sheets and 10000 sheets. The angle θ
Was ± 20 degrees, it was good at 5,000 sheets, but cleaning failure occurred at 10,000 sheets. When the angle θ was ± 25 degrees, the cleaning failure occurred after 5,000 sheets.

From the above, the direction of the resultant force F of the pressure applied to the image carrier 6a of the developing sleeve 7f and the transfer drum 4 is within ± 15 degrees with respect to the image carrier contact position of the cleaning blade 6c1. It was found that stable cleaning ability can be obtained by setting. When the contact position of the cleaning blade 6c1 with respect to the image bearing member is ± 20 degrees or more, the pressure of the cleaning blade 6c1 cannot counteract the change in the pressure applied to the image bearing member 6a of the developing sleeve 7f, and the image bearing member 6a is not able to compete. It is considered that the position of is changed and cleaning failure occurs.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a layout explanatory view of process means acting on the image carrier. The components having the same configurations and functions as those of the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, as the charging means 6b, a charging roller having a conductive layer and a resistance layer provided on a cored bar is used. The roller is brought into contact with the image carrier 6a, and a bias voltage in which alternating current is superimposed on direct current is applied. Image carrier 6a by applying
The surface of is uniformly charged.

The charging roller faces the image carrier 6a.
It is pressurized with a force of 200 to 400 g, and is indicated by the arrow Fch in Fig. 5.
The power is represented by. The developing sleeve 7f and the transfer drum 4 are pressed toward the center of the image carrier 6a with a pressing force of 1 kg, similarly to the above-described embodiment, and are indicated by arrows Fdev and Ftr in FIG. An arrow F in FIG. 5 represents the resultant force of the arrows Fch, Fdev, and Ftr, and the angle formed by the contact position of the cleaning blade 6c1 with the image carrier 6a is θ.

Also in the present embodiment, the angle θ is changed by changing the contact position of the cleaning blade 6c1 with the image carrier, and the occurrence of cleaning failure is examined.
When the angle θ was in the range of 0 to ± 15 degrees, good cleaning characteristics were exhibited and no cleaning failure occurred.

The charging means is the wire type,
In addition to the roller type, blade type (charging blade), pad type, block type, rod type and the like may be used.

[Third Embodiment] Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a layout explanatory view of process means acting on the image carrier. The components having the same configurations and functions as those of the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, as the transfer drum 14, an elastic layer 14b such as sponge or rubber is formed on the outer circumference of an aluminum cylinder 14a as a conductive base, and a resistance layer is formed on the outer circumference thereof.
14c is formed, and the dielectric layer 14d is formed on the outermost periphery. Compared with the transfer drum 4 in the above-described embodiment, the transfer drum 14 has the advantages that the number of chargers is reduced, the apparatus is simplified, the cost is reduced, and the generation of ozone harmful to the human body is reduced. Since the entire width of the layer 14d is supported by the conductive substrate 14a and the elastic layer 14b, the mechanical strength is increased and the life of the transfer drum is extended.

Since the dielectric layer 14d supported by the elastic layer 14d is in contact with the transfer drum 14 over the entire width of the transfer area, the pressure on the image carrier 6a becomes high, and in this case, 2 kg.
The image carrier 6a is pressed by heavy pressing force, and its force is represented by an arrow Ftr in the figure. Further, the charging roller 6b and the developing sleeve 7f press the image carrier 6a with a pressing force of 200 to 400 g weight and 1 kg weight, respectively, as in the above-described embodiment, and are indicated by arrows Fch and Fdev in the figure. There is.
The resultant force of the forces Ftr, Fch, Fdev is represented by arrow F.

Also in this embodiment, the angle θ was changed by changing the contact position of the cleaning blade 6c1 with the image carrier, and the occurrence of cleaning failure was examined.
When the angle θ was in the range of 0 to ± 15 degrees, good cleaning characteristics were exhibited and no cleaning failure occurred.

[Other Embodiments] In the above-described embodiments, an apparatus for forming a color image by providing four developing devices has been exemplified.
The image forming apparatus according to the present invention is not limited to the color image forming apparatus but can be applied to a monochrome image forming apparatus having one developing device.

Further, the present invention can be applied to an image forming apparatus for forming an image by mounting a process cartridge in which an image carrier unit and a developing device are integrally made into a cartridge.

Further, although the laser beam printer has been illustrated in the above-mentioned embodiments, it is naturally possible to apply the present invention to, for example, a copying machine, a facsimile machine or the like in addition to the aspect of the apparatus.

As the developing method, it is possible to use various developing methods such as a known two-component magnetic brush developing method, cascade developing method, touch-down developing method and cloud developing method.

Further, as a method of cleaning the toner remaining on the image carrier, the cleaning means may be constituted by using a blade, a fur brush, a magnetic brush or the like.

[0063]

As described above, the direction of the resultant force of the pressing force of the developing device against the image carrier and the pressing force of the transfer device against the image carrier is substantially the contact position of the image carrier against the cleaning device. Since it is preferably set so as to go within the range of ± 15 degrees of the image carrier contact position of the cleaning means, even when the developing means performs switching corresponding to the development corresponding to each color component, The contact state of the cleaning means with the image carrier is stabilized, and defective cleaning can be prevented. Also, when using a contact type charging means for charging in a state of being in contact with the image carrier,
The direction of the resultant force and the applied force of the charging means to the image carrier is approximately within a range of ± 15 degrees of the image carrier contact position of the cleaning means, preferably the image carrier contact position of the cleaning means. Since it is set so as to face toward, it is possible to obtain the same effect as described above.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the overall configuration of a laser beam printer that is an aspect of an image forming apparatus of the present invention.

FIG. 2 is an explanatory diagram showing a contact state of a developer carrier and a transfer unit with respect to an image carrier.

FIG. 3 is an enlarged schematic diagram of a developing unit.

FIG. 4 is a layout explanatory view of process means acting on an image carrier.

FIG. 5 is an explanatory diagram of an arrangement of process means acting on the image carrier.

FIG. 6 is a layout explanatory view of process means acting on an image carrier.

FIG. 7 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cassette, 1a ... Locking convex part, 2 ... Recording medium, 3 ... Feeding means, 3a, 3b ... Feeding roller, 3c ... Guide plate, 3
d ... Registration roller, 4 ... Transfer drum, 4a ... Support,
4b ... derivative sheet, 4c ... axis, 4d ... gripper, 4
e ... electrostatic attraction roller, 4f ... contact member, 4g ... eccentric cam, 5 ... optical unit, 5a ... laser diode, 5
b ... Polygon mirror, 5c ... Scanner motor, 5d ...
Imaging lens, 5e ... Reflective mirror, 6 ... Image carrier unit, 6a ... Image carrier, 6a1 ... Rotation axis, 6b ... Charging means,
6c ... Cleaning means, 6c1 ... Cleaning blade, 6c2 ... Waste toner conveying screw, 6d ... Image carrier unit cover, 7 ... Developing means, 7a to 7d ... Developing device, 7
a1 to 7d1 ... Axis, 7e ... Developing unit, 7e1 ... Axis, 7f ...
Developing sleeve, 7g ... eccentric cam, 7h ... contact member, 7i
... toner feeding mechanism, 7j ... coating roller, 7k ... developing blade, 8 ... fixing means, 8a ... drive roller, 8b ... fixing roller, 8c ... cleaning member, 9 ... discharge roller, 10 ...
Ejection unit, 11 ... Device body, 11a ... Guide rail, 12 ... Separation claw, 13 ... Cleaning device, 14 ... Transfer drum, 14a ... Aluminum cylinder, 14b ... Elastic layer, 14c ... Resistive layer, 14d ... Dielectric layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuya Kobayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Akihiko Uchiyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Hiroshi Sasame 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Haruo Fujii 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (2)

[Claims] 1. An image carrier is charged by a charging unit, a latent image formed on the image carrier is developed by a developing unit, and the developed image is transferred to a recording medium by a transfer unit, and then the image carrier is formed. An image forming apparatus for removing the developer remaining on the upper surface by a cleaning unit, wherein a direction of a resultant force of a pressing force of the developing unit on the image carrier and a pressing force of the transfer unit on the image carrier is the image direction. ± 15 with respect to the abutting part of the cleaning means on the carrier
An image forming apparatus, wherein the image forming apparatus is set to be within a range of degrees. 2. An image bearing member is charged by a charging unit, a latent image formed on the image bearing member is developed by a developing unit, the developed image is transferred to a recording medium by a transfer unit, and then the image bearing member is formed. An image forming apparatus for removing the developer remaining on the upper surface by a cleaning unit, the pressing force of the charging unit on the image carrier, the pressing force of the developing unit on the image carrier, and the transfer unit to the image carrier. The image forming apparatus is characterized in that the direction of the resultant force with the pressing force is set within a range of ± 15 degrees with respect to the contact portion of the cleaning means with respect to the image carrier.