JP3267052B2 - Image carrier for image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image carrier such as a photosensitive drum or a dielectric drum used in an image forming apparatus such as an electrophotographic copying machine, a laser beam printer, and an electrostatic recording apparatus. Also, the present invention relates to an image carrier that can prevent generation of noise when a roll-shaped charging member is used as a charging unit that uniformly primary charges the surface of the image carrier.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus such as an electrophotographic copying machine, a laser beam printer, or an electrostatic recording apparatus generally charges the surface of a photosensitive drum uniformly by a charging means, and then charges the photosensitive drum. The electrostatic latent image is formed by exposing the surface of the drum to an image, and the electrostatic latent image is developed to form an image. As a charging unit used in such an image forming apparatus, a discharge wire is stretched along a longitudinal direction inside a shield member, and a high voltage is applied to the discharge wire to generate a corona discharge, which is generated by the corona discharge. A so-called corotron, which applies a charging process to the surface of an image carrier such as an electrophotographic photosensitive drum or an electrostatic recording type dielectric drum by the ions to be used, is widely used. This corotron is an effective device as a means for uniformly charging the surface of the image carrier. However, since a high voltage of several Kv is required to charge a photosensitive drum or the like to a predetermined surface potential, a corona is used. Oxygen in the air reacts by the discharge to generate ozone, and the strong oxidizing action of the ozone causes deterioration of rubber parts and the photoreceptor. Therefore, in the case of the above corotron, ozone generated by corona discharge is applied to other rubber parts, photoconductors and the like in order to prevent ozone generated by corona discharge from causing deterioration of rubber parts and photosensitive drums. In order to prevent contact, it is necessary to consider the material and shape of the corotron, and to install measures such as installing an exhaust fan that forcibly exhausts ozone. For this reason, there is a problem that the cost is greatly increased due to the complicated configuration of the apparatus.

In the case of the above-mentioned corotron, since the discharge wire is contaminated by dust in the air or oil used in the fixing device, image unevenness due to discharge unevenness is likely to occur. Need to be set up,
Also from this point, there is a problem that the configuration of the apparatus becomes complicated and the cost is increased.

Therefore, as a charging means in place of the corotron used in the above-described image forming apparatus, a roll to which a bias voltage is applied is brought into contact with an image carrier such as a photosensitive drum, so that the image carrier such as a photosensitive drum is charged. Attention has been paid to a charging device for charging a surface.

[0005] This charging means provides an AC voltage V _DC having a DC voltage _VDC and a peak-to-peak voltage V _PP which is at least twice the charging start voltage of the member to be charged with respect to a roll-shaped charging member for the purpose of uniform charging. a contact charging method or apparatus which is based on applying the V _DC + V _AC obtained by superimposing an _AC.

FIGS. 10 and 11 show an example of an image forming apparatus using the charging means of the contact charging system.

In FIG. 1, reference numeral 100 denotes a photosensitive drum 101.
Is a roll-type charging member that is in contact with. The roll-type charging member 100 is disposed in parallel with the photosensitive drum 101, and is rotatably supported by a bearing (not shown) via both ends of a cored bar 102. Further, the roll-type charging member 100 is urged to press against the photosensitive drum 101 by pressurizing springs 103 attached to both ends of the cored bar 102, and has a predetermined pressing force against the photosensitive drum 101. The photosensitive drum 101 is pressed and rotated by the rotation of the photosensitive drum 101.

Reference numeral 104 denotes a leaf spring as an electrode for applying a predetermined voltage to the roll-type charging member 100 from a voltage application power supply (not shown).
Is adapted to apply a predetermined AC superimposed DC voltage to the roll-type charging member 100 through the cored bar 102.

[0009] The charging device of the contact charging system is
By applying a predetermined voltage to the roll-type charging member 100 as described above, the surface of the photosensitive drum 101 is uniformly charged to a desired potential.

[0010]

However, the above-mentioned prior art has the following problems. That is, in the above-described image forming apparatus, the roll-type charging member 10 for bringing the charging member into direct contact with the surface of the photosensitive drum 101 is used.
When 0 is used, there is a problem that noise due to charging noise is generated. In this contact type charging means, a charging member which is in contact with the photosensitive drum 101, in this case, a roll type charging member 100,
0, an AC voltage component is applied to the roll-type charging member 10.
A vibration sound is generated between 0 and the photosensitive drum 101 due to the AC voltage component. The mechanism of generating this vibration sound is disclosed in Japanese Patent Application Laid-Open No. 4-86682.

As described above, in the image forming apparatus configured as described above, the tube 1 such as the photosensitive drum having a hollow inside is used.
01, when an external force, which is mechanical vibration, is applied from the outside by the roll-type charging member 100, noise is generated at a specific frequency corresponding to the length of the cavity of the tube 101 such as the photosensitive drum. is there. The frequency f of this noise depends on the internal length 1 in the pipe axis direction and the sound velocity v which is substantially governed by the atmospheric temperature.
And the relationship of f = v ÷ 1 holds. However, it is known from widely known facts that the fundamental frequency f _n is １ ／ of the frequency f.

Generally, the length of an image carrier such as a photosensitive drum in the axial direction is slightly longer than the paper size of a printed material. Is 22 in the axial direction.
Since the sound velocity v is in the range of about 0 to 430 mm,
m / sec, the fundamental frequency f _n is 400 Hz to 7
There is a situation where noise of a harmonic component having a fundamental frequency of 70 Hz is easily generated. The audible frequency range of humans is generally in the range of 20 Hz to 20 KHz,
When noise of a harmonic component having a fundamental frequency of z to 770 Hz is generated, there is a problem that a user using the image forming apparatus feels extremely uncomfortable and inconvenient results occur.

As a technique for solving the problem of noise generation from the photosensitive drum and the like caused by using such a roll-type charging member, a technique disclosed in Japanese Patent Application Laid-Open No. 5-34936 has been disclosed. I have. Japanese Patent Application Laid-Open No. 5-349
The method for manufacturing an electrophotographic photoreceptor according to Japanese Patent Publication No. 36 (1996) is configured such that a lubricant is attached to at least the surface of a filler having an elastic body on a surface layer, and is inserted inside the electrophotographic photoreceptor.

However, in the method of manufacturing an electrophotographic photosensitive member according to Japanese Patent Application Laid-Open No. 5-34936, a reduction in vibration noise is aimed at by inserting a filler inside the electrophotographic photosensitive member. However, in the case of such a technique, it is necessary to insert a filler inside the electrophotographic photoreceptor, in addition to an increase in cost due to an increase in parts and an increase in manufacturing cost due to an increase in a press-in step of the filler. Therefore, there is a problem that the driving force when the electrophotographic photosensitive member is rotationally driven is increased by increasing the weight of the electrophotographic photosensitive member.

Therefore, the present invention has been made to solve the above-mentioned problems of the prior art, and its object is to increase the cost due to an increase in the number of parts, the increase in the number of manufacturing steps, and the image. An object of the present invention is to provide an image carrier for an image forming apparatus capable of minimizing an increase in the weight of the carrier and effectively preventing generation of noise.

[0016]

According to a first aspect of the present invention, there is provided an image carrier for an image forming apparatus, wherein a charging member is brought into contact with the surface of a drum-shaped image carrier to form the drum-shaped image carrier. in the image bearing member to uniformly charge the surface of the image bearing member used in an image forming apparatus for forming an image, said Dora
Part of the noise generated in the image carrier
Sound reflection interference means that cancel noise should be canceled
The axis in the drum-shaped image carrier determined by the wavelength of the noise
It is obtained by configuration so that provided in a predetermined position in the direction.

Further, the image forming apparatus for image bearing member according to Claim paragraph 2 of this invention, is the sound wave reflected interference means, de
The drum is arranged so as to be orthogonal to the axial direction of the ram-shaped image carrier.
Disk-shaped or semi-disk mounted inside the image carrier
A sound wave reflection interference plate,
Is about 1/2 to 1 of the axial length of the drum-shaped image carrier.
The internal cross-sectional area of the drum-shaped image carrier is 90 to 2 at the internal position of the drum-shaped image carrier corresponding to the position having a length of / 16.
They are arranged so as to occupy 0% of the area.

Further, according to a third aspect of the present invention, in the image carrier for an image forming apparatus, the sound wave reflection interfering means may include:
The drum is set so as to be orthogonal to the axial direction of the drum-shaped image carrier.
Disk-shaped or semi-circular mounted inside the image carrier
It consists of a plate-shaped sound reflection interference plate,
The step is formed such that the end of the drum-shaped image carrier and the end of the drum-shaped carrier have a length substantially equal to の of the axial length of the drum-shaped image carrier.
And an internal position of the drum-shaped image carrier corresponding to a position 1/16 of the length of the drum-shaped image carrier so as to occupy an area of 90 to 20% of the internal cross-sectional area of the drum-shaped image carrier. Things.

As the sound wave reflection interference means, for example,
A hard material without a low-frequency absorption effect (metal plate, high reflectivity) is used, but if it is desired to have an effect of absorbing higher frequencies as well, a plastic or the like excellent in high-frequency attenuation characteristics may be used. .

Further, the above-mentioned sound reflection interference member may be, for example,
It is provided at a position one fourth of the wavelength of the noise to be attenuated.

[0021]

In the image carrier for an image forming apparatus according to the present invention, a charging member is brought into contact with the surface of a drum-shaped image carrier to uniformly charge the surface of the drum-shaped image carrier to form an image. In the image carrier used in the image forming apparatus for performing the above, a sound reflection interference unit is provided inside the drum-shaped image carrier.

An image carrier used in an image forming apparatus for forming an image by uniformly charging the surface of the drum-shaped image carrier by bringing a charging member into contact with the surface of the drum-shaped image carrier. In the body, when an external force is applied from outside of the drum-shaped image carrier by a contact-type charging member, for example, as shown in FIG. Harmonic noise is generated. Here, a sound wave is written as a transverse wave for the purpose of drawing, but it is also a well-known fact that the wave is actually a longitudinal wave having a density. That is, the oscillating pressure wave generated from one end of the tube travels through the air serving as the medium in the tube and moves to the other end. At this time, paying attention to the portion of the longitudinal wave having the highest density and considering the 基本 fundamental frequency, when this portion reaches the other end, the one end has the lowest density. If the unevenness of the density distribution can be corrected, longitudinal waves will not exist, and no noise will be generated. In other words, if the densest part and the least dense part are in the same place at the same time, they can cancel each other out,
Noise can be reduced. As mentioned above, 1/2
At the fundamental frequency, the density changes are exactly in opposite phases at one end and the other end, and the countermeasures cannot be realized if this state is maintained.

Therefore, as shown in FIG. 5, when the sound wave reflection interference member 26 is provided in the drum-shaped image carrier 1, a part of the portion having the highest density moving from one end to the other end is provided. Is reflected by the sound wave reflection interference plate 26, and returns to one end side. When the position of the sound wave reflection interference plate 26 reaches a portion with the highest density at the other end, that is, when the density at one end is the lowest density,
If part of the densest part of the reflected density is reached, the densest part and the least dense part will be in the same place at the same time, and the noises can cancel each other. , Noise can be reduced. If the position of the sound wave reflection interference member 26 is substantially at the center of the wavelength, the above-described effect is produced.

The same can be said for other frequencies. In other words, even at the fundamental frequency and its integral multiple harmonic frequencies, when the density at one end is the lowest density, if the part of the densest part of the reflected density reaches, You can achieve your aim. However, since the wavelength is different, the place where the reflecting member should be installed is also different. For example, when it is desired to reduce the fundamental frequency, a position that is approximately の of the length of the drum-shaped image carrier is optimal, and a position that is １ ／ of the wavelength of each frequency is optimal for attenuation of each frequency. It can be seen that it is. Further, according to the principle of non-interference of waves, it is also possible to provide a sound reflection interference member of a required size at a position of 1/4 of each frequency, and the same effect is exerted. In application to actual equipment,
It is sufficient to take countermeasures for some frequencies that are most worrisome in mechanical configurations with different conditions, for example, 1 kHz to 2 kHz as the most worrisome frequency band. , Fn is 400 to 77
0 Hz, which indicates that measures up to the third harmonic are sufficient.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

FIG. 2 shows an image forming apparatus to which an embodiment of an image carrier for an image forming apparatus according to the present invention is applied.

In FIG. 2, reference numeral 1 denotes a photosensitive drum as an image bearing member. As the photosensitive drum 1, for example, a photosensitive drum using an organic photoconductor (OPC) is used. The photosensitive drum 1 is driven to rotate at a predetermined process speed in a direction indicated by an arrow by a drive mechanism (not shown). Further, the surface of the photosensitive drum 1 is provided with a charging means 2 comprising a roll-shaped charging member.
As a result, it is uniformly charged to a predetermined potential. On the outer periphery of the photosensitive drum 1, an LED head 3 as a solid-scanning optical writing head for exposing the drum surface in accordance with image data is arranged adjacent to the charging device 2 on the downstream side in the drum rotation direction. I have. In addition, as the image exposure means, L
In addition to the ED head 3, a light lens type exposure device, a laser beam exposure device, or the like may be used.

The surface of the photosensitive drum 1 uniformly charged as described above is subjected to image exposure by the LED head 3, whereby an electrostatic latent image corresponding to image data is formed.

As shown in FIG. 2, the electrostatic latent image formed on the photosensitive drum 1 is developed by a developing roll 5 of a developing device 4 to become a toner image. The toner image formed on the photosensitive drum 1 is simultaneously transferred and fixed onto the transfer paper 6 supplied from a paper cassette (not shown) by the pressing force of the transfer roll 7.

After the toner image transfer process is completed, the surface of the photosensitive drum 1 is cleaned of residual toner and paper dust by a cleaner 8 having a cleaning blade to prepare for the next image forming process.

FIG. 3 shows a contact type charging device according to this embodiment.

In the figure, reference numeral 10 denotes a roll-type charging member which is in contact with the photosensitive drum 1, and the roll-type charging member 10 is arranged in parallel with the photosensitive drum 1. The roll-type charging member 10 is configured by coating an elastic body 12 to a predetermined thickness on a surface of a core metal 11 made of SUS or the like. As the roll-type charging member 10, for example, the outer diameter of the core metal 11 is 6.0 mm, and the roll-type charging member 1
0 has an outer diameter of 12.0 mm and the length of the elastic body 12 is 230 m
m.

Further, the above-mentioned roll-type charging member 10 is provided as shown in FIG.
As shown in FIG. 1, both ends of the cored bar 11 are rotatably supported by bearings (not shown), and are pressed against the photosensitive drum 1 by pressure springs 13 attached to both ends of the cored bar 11. And is pressed against the photosensitive drum 1 with a predetermined pressing force.
It is designed to rotate following the rotation of.

Further, as shown in FIG. 2, the core metal 11 of the roll-type charging member 10 is used as an electrode for applying a predetermined AC superimposed DC voltage from a voltage applying power source to the roll-type charging member 10. Of the roll type charging member 1 through the cored bar 11 from the leaf spring 14.
A predetermined voltage is applied to 0.

The contact type charging device 2 uniformly charges the surface of the photosensitive drum 1 to a desired potential by applying a predetermined AC superimposed DC voltage to the roll type charging member 10 as described above. It is configured to be.

When the roll charging member 10 is used as the charging means, the photosensitive drum 1
Charging member, in this case, a roll-type charging member 1
When an AC voltage component is applied to the roll-type charging member 10, the roll-type charging member 10 and the photosensitive drum 1
A vibration sound due to the AC voltage component is generated between the two.

The photosensitive drum as an image carrier according to this embodiment is configured as follows. That is, as shown in FIG. 1, the photosensitive drum 1 is configured by forming a coating 21 of a photosensitive material such as OPC on the surface of a cylinder 20 made of aluminum or the like. A flange member 22 is fitted to one end of the aluminum cylinder 20 of the photosensitive drum 1 in a fitted state, and one end of the aluminum cylinder 20 is hermetically closed by the flange member 22. The other end of the aluminum cylinder 20 is also closed by another member (not shown).

On the flange member 22 of the photosensitive drum 1, a curved band member 25 having a curvature equal to the curvature of the cylindrical portion 22a of the flange member 22 projects toward the other end of the aluminum cylinder 20. Has been established. The band-shaped member 25 is arranged in parallel with the inner surface of the aluminum cylinder 20 with a predetermined gap from the inner surface of the aluminum cylinder 20. In addition, the belt-like member 25 has a structure shown in FIG.
As shown in FIG. 2, two disc-shaped sound reflection interference plates 2 made of an iron-based sheet metal are orthogonal to the axial direction of the photosensitive drum 1.
6, 27 are respectively attached to predetermined positions by means such as adhesion using a hot melt resin. The first sound wave reflection interference plate 26 is arranged at a quarter of the wavelength of the noise of the fundamental frequency from the inner surface of the flange member 22 of the photosensitive drum 1, and the second sound wave reflection interference plate 27
Are arranged at half the wavelength of the noise of the fundamental frequency from the inner surface of the flange portion 22 of the photosensitive drum 1.

Now, the inner diameter of the photosensitive drum 1 is 30 mm,
When the inner tube length 1 is 330 mm, the fundamental frequency fn is about 515 Hz. Therefore, the mounting positions of the first and second sound wave reflection interference plates 26 and 27 are set at two places of 41.25 mm and 82.5 mm as と し て and の of the wavelength. The diameter of the first and second sound wave reflection interference plates 26 and 27 is set to 20 mm. Thus, the provision of the first and second sound wave reflection interference plates 26 and 27 aims at reducing the 基本 fundamental frequency and the fundamental frequency.

As described above, when an external force as vibration generated by the roll-type charging member 10 acts on the photosensitive drum 1 from the outside, as shown in FIG. As a result, noise of a harmonic that is an integral multiple of the fundamental frequency including the noise is generated. Here, the sound wave is written as a transverse wave due to the drawing,
It is also a well-known fact that the waves are actually longitudinal waves with density variations. That is, the oscillating pressure wave generated from one end of the photosensitive drum 1 propagates through the air, which is the medium in the tube, and propagates to the other end. At this time, paying attention to the portion of the longitudinal wave having the highest density, and considering the 基本 fundamental frequency,
When this part reaches the other end, one end has the lowest density. If the unevenness of the density distribution can be corrected, longitudinal waves will not exist, and no noise will be generated. That is,
If the parts having the highest density and the parts having the lowest density are present at the same place at the same time, the sound waves are canceled each other and the noise is reduced. As described above, at the 基本 fundamental frequency, the density changes are exactly in opposite phases at one end and the other end, and the countermeasures cannot be realized without any change.

For this reason, as shown in FIG. 5, when the sound wave reflection interference plate 26 is provided inside the photosensitive drum 1, a part of the portion having the highest density which moves from one end to the other end has a part. The light impinges on the sound wave reflection interference plate 26 and is reflected, and returns to one end side. When the position of the sound wave reflection interference plate 26 reaches a portion with the highest density at the other end, that is, when the density at one end is the lowest density,
The above aim can be achieved if a part of the densest part of the reflected density is reached. In other words, if the part having the highest density and the part having the lowest density are simultaneously present in the same place, the sound waves are canceled each other and the noise is reduced. If the position of the sound wave reflection interference plate 26 is substantially at the center of the wavelength, the above-described effect is produced. In the experiment, it was better that the sound reflection interference plate 26 was made of a hard material having no low-frequency absorption effect (a metal plate, having a high reflectance). Plastic or the like having excellent attenuation characteristics may be used.

The same can be said for other frequencies. In other words, even at the fundamental frequency and a harmonic frequency that is an integral multiple of the fundamental frequency, when the density at one end is the lowest density, if the part of the densest part of the reflected density reaches, Can achieve the aim. However, since the wavelength is different, the place where the reflector is to be installed is also different. For example, when it is desired to reduce the fundamental frequency, it is understood that the position at approximately の of the tube length is optimal, and the position at １ ／ of the wavelength of each frequency is optimal for the attenuation of each frequency. Further, according to the principle of non-interference of waves, it is also possible to provide a sound reflection interference plate of a required size at a position of 1/4 of each frequency, and the same effect is exerted. In application to an actual machine, it is only necessary to take measures for some frequencies that are most worrisome in mechanical configurations with different conditions, and for example, the most worrisome frequency band includes 1 kHz to 2 kHz. From the relationship with the printing paper described above, it can be seen that fn is 400 to 770 Hz, and therefore, measures up to the third harmonic are sufficient.

Next, in order to confirm the effect of the present invention, the present inventor prototyped an apparatus as shown in FIG. 1 and conducted an experiment for comparing the state of noise generation with the conventional case in which no sound wave reflection interference plate was provided. Was done. FIG. 6 shows the results of this experiment.

As shown in FIG. 6, the noise measurement results show the intended reduction. If the area of the sound wave reflection interference plate is increased, the attenuation effect can be further enhanced.

Second Embodiment FIG. 7 shows a second embodiment of the present invention. The same parts as those of the above embodiment are denoted by the same reference numerals and described. In the second embodiment, FIG. As described above, one of the flange portions of the photosensitive drum was opened, and the belt-shaped member was taken out from the flange portion, raised at a right angle to the radial direction of the photosensitive drum, and a sound reflection interference plate made of iron-based sheet metal was attached by a hot melt method. Things. In this case, due to well-known facts, the lowest resonance frequency is further reduced to １ ／, and the tube length is reduced to の of the wavelength of the lowest resonance frequency.

When the inner diameter of the photosensitive drum is 30 mm and the inner tube length 1 is 240 mm, the fundamental frequency fn is about 354 Hz. For this reason, the mounting position of the first and second sound wave reflection interference plates is one of the wavelengths.
/ 4 and １ ／ are set at two positions of 48 mm and 80 mm, and the diameters of the first and second sound reflection interference plates are set to 20 mm. Thus, the first
And providing the second sound reflection interference plate,
(2) The purpose is to reduce the fundamental frequency and the fundamental frequency.

Next, in order to confirm the effect of the present invention, the present inventor prototyped an apparatus as shown in FIG. 7 and conducted an experiment to compare the state of noise generation with the conventional case without the sound wave reflection interference plate. Was done. FIG. 8 shows the results of this experiment.

As shown in FIG. 8, the noise measurement results show the intended reduction. If the area of the sound wave reflection interference plate is increased, the attenuation effect can be further enhanced.

The other configuration and operation are the same as those of the above-described embodiment, and the description is omitted.

Third Embodiment FIG. 9 shows a third embodiment of the present invention. The same portions as those of the above embodiment are denoted by the same reference numerals and described. In the third embodiment, FIG. As such, the shape of the sound wave reflection interference plate is not a disk shape but a semi-disk shape, and the sound wave reflection interference plates of the semi-disk shape are arranged so that the upper and lower positions are opposite to each other. Are located.

The other constructions and operations are the same as those of the above-described embodiment, and the description is omitted.

[0052]

The present invention has the above-mentioned structure and operation, and minimizes the increase in cost due to the increase in the number of parts, the increase in the number of manufacturing steps, and the weight of the image carrier. An image carrier for an image forming apparatus capable of effectively preventing generation of noise can be provided.

[Brief description of the drawings]

FIGS. 1A and 1B are cross-sectional views of an essential part showing an embodiment of an image carrier for an image forming apparatus according to the present invention, and FIGS.
It is a bb line sectional view of (a).

FIG. 2 is a configuration diagram showing an embodiment of an image forming apparatus to which the image carrier for an image forming apparatus according to the present invention is applied.

FIGS. 3A and 3B are a front view and a side view, respectively, showing a charging unit.

FIG. 4 is an explanatory diagram showing a state of a sound wave reflected inside the image carrier.

FIG. 5 is an explanatory diagram showing a state of a sound wave reflected inside the image carrier.

FIG. 6 is a graph showing a noise attenuation state.

7 (a) and 7 (b) are a sectional view of a main part showing a second embodiment of the present invention and a sectional view taken along line bb of FIG. 7 (a).

FIG. 8 is a graph showing a noise attenuation state.

9 (a) and 9 (b) are a sectional view of a main part showing a third embodiment of the present invention and a sectional view taken along line bb of FIG. 9 (a).

FIG. 10 is a configuration diagram illustrating a conventional image forming apparatus.

FIG. 11 is a front view showing a charging unit.

[Explanation of symbols]

Reference Signs List 1 photoreceptor drum (image carrier), 10 roll-shaped charging member, 22 flange member, 25 belt-shaped member, 26, 27
Sound wave reflection interference plate.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-281773 (JP, A) JP-A-5-34936 (JP, A) JP-A-6-95560 (JP, A) JP-A-5-95560 197321 (JP, A) JP-A-64-58454 (JP, A) JP-A-63-155142 (JP, A) JP-A-3-105348 (JP, A) JP-A-5-35167 (JP, A) JP-A-3-45981 (JP, A) JP-A-3-44689 (JP, A) JP-A-63-271388 (JP, A) JP-A-5-188838 (JP, A) JP-A-5-188839 (JP, A) JP-A-5-188840 (JP, A) JP-A-5-224506 (JP, A) JP-A-6-67512 (JP, A) JP-A-1-146264 (JP, U) ( 58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 5/00 G03G 21/00

Claims (3)

(57) [Claims] An image carrier used in an image forming apparatus for forming an image by uniformly charging the surface of a drum-shaped image carrier by bringing a charging member into contact with the surface of the drum-shaped image carrier. Of the noise generated in the drum-shaped image carrier
Sound reflection interference that partially reflects and cancels each other's noise
The means are determined by the noise wavelength to be canceled.
An image carrier for an image forming apparatus, which is provided at a predetermined position in an axial direction within a ram-shaped image carrier . 2. The image processing apparatus according to claim 1, wherein the sound reflection interference unit is a drum-shaped image bearing unit.
The drum-shaped image carrier so as to be orthogonal to the axial direction of the carrier.
Disk-shaped or semi-disk-shaped sound wave installed inside
The sound wave reflection interference means is provided at an internal position of the drum-shaped image carrier corresponding to a position having a length of about 1/2 to 1/16 of an axial length of the drum-shaped image carrier. 2. An image carrier for an image forming apparatus according to claim 1, wherein said image carrier is arranged so as to occupy an area of 90 to 20% of an internal sectional area of said drum-shaped image carrier. 3. The image processing apparatus according to claim 2, wherein the sound reflection interference means is a drum-shaped image bearing member.
The drum-shaped image carrier so as to be orthogonal to the axial direction of the carrier.
Disk-shaped or semi-disk-shaped sound wave installed inside
The sound wave reflection interfering means comprises a reflection interference plate, and the sound reflection interference means comprises an end portion of the drum-shaped image carrier, and approximately か ら to 1 of an axial length of the drum-shaped image carrier from the end portion of the drum-shaped carrier. / 16
90% to 20% of the internal cross-sectional area of the drum-shaped image carrier at the internal position corresponding to the length of the drum-shaped image carrier.
2. The image carrier for an image forming apparatus according to claim 1, wherein the image carriers are arranged so as to occupy an area of the image carrier.